JPH04295657A - Magnetic recording-reproducing device - Google Patents

Abstract

PURPOSE:To stabilize both normal recording-reproduction and still recording production in a satisfactory extent by changing a tape reference position during speed change time in such a fashion that an angle formed by a tape reference edge and a recording trace may be under the same condition during both travel and suspension of the tape. CONSTITUTION:A ring-shaped guide member 31 is fitted into a drum base DF where a gear 30 of the guide member 31 is engaged with a gear 32 of a rotary drive motor 34. The guide member 31 is installed so that it may be rotated by the drive of the motor 34. Under this construction, the rotary drive motor 34 is rotated in a normal or reverse direction in conformity with the change over of the rotary speed so that the angle formed by the reference edge of the magnetic tape and the recording trace by a magnetic head Ha may be in the same condition during both travel and suspension. As a result, a guide plane 31a of the guide member 31 is capable of controlling the angle formed by the reference edge and the recording trace, while being guided by the reference edge of the magnetic tape.

Description

[Detailed description of the invention]

0001

[Industrial Field of Application] The present invention relates to a magnetic recording/reproducing device, and more particularly, to a magnetic recording/reproducing device, which detects the reference edge of a magnetic tape and recording traces when the magnetic tape is running at a predetermined running speed and when it is stopped. In this magnetic recording and reproducing apparatus, the position of the reference edge of the magnetic tape is changed in accordance with changes in running speed so that the angle formed by the magnetic tape remains the same.

0002

2. Description of the Related Art A video tape recorder (VTR) is a typical example of a magnetic recording and reproducing device that uses a rotating magnetic head to record and reproduce information signals on a magnetic tape.
can be mentioned. It is well known that the VTRs currently in use have greatly improved image quality and functionality due to dramatic advances since their development. Currently, the development of digital VTRs for recording is progressing. On the other hand, a VTR uses a rotating magnetic head on a magnetic tape to record and reproduce information signals.
was generally used to record continuous images, such as recording the contents of television broadcast programs or recording video signals captured by television cameras.
Taking note of the large storage capacity of the magnetic tape in VTRs, attempts have been made to use VTRs, for example, as a storage device in digital information processing equipment or as one of the other components. .

By the way, a VTR can be used as a component of a digital information processing device, for example, as an ``external auxiliary storage device for a computer'' or as a ``computer graphics image that is recorded sequentially at the end of calculation and played back continuously.'' When used in devices such as "devices for producing moving pictures," information signals may be recorded on magnetic tape in units of one recording trace (1 track) to several tracks. In order for a VTR to be used as a component of a digital information processing device, the recording operation of information in units of, for example, one track to several tracks must be realized with high stability and reliability, as described above. It is necessary to do so. In a VTR that uses a rotating magnetic head to record and reproduce information signals on a magnetic tape, recording is performed on a specific track on the magnetic tape, or rewriting the recorded content on a specific track on the magnetic tape. In such cases, ■
The magnetic tape is rewound to a position before the scheduled recording start position by pre-rolling, and during recording, the magnetic tape starts running from the rewound position and passes through the scheduled recording start position at a predetermined tape feed speed. , so that recording is performed on a predetermined number of tracks from the scheduled recording start position, or ■ Stop the magnetic tape at the position where recording is to be performed by control pulses and rotational position control of the capstan motor, and stop the magnetic tape in the stopped state. Recording is performed on the tape using a rotating magnetic head. Two methods have been conventionally used.

[0004] The above-mentioned method (1) is carried out in the assembly recording/insert recording mode of the editing function of the VTR.
In this method, it is necessary to repeatedly rewind and feed the magnetic tape in the forward direction every time recording is performed on the magnetic tape, which places a burden on the tape running mechanism and the magnetic tape. It is not suitable for cases where recording operations are performed frequently, and the running speed of the running magnetic tape is unstable, which inevitably places a heavy burden on the running system. It is difficult to set the position with such high precision as to show good linearity, and furthermore, there are various problems such as the fact that the recording time interval cannot be shortened because pre-rolling etc. takes time. In addition, in the method (2) described above, in addition to not requiring the rewinding operation required in the method (2) described above, the recording operation is performed while the magnetic tape is stopped, so the tape running system is not required. This has the advantage that it does not place a large burden on the magnetic tape and the magnetic tape, and it is easy to set the track position with high precision. On the other hand, since the recording is performed using a rotating magnetic head, the track pattern recorded on the magnetic tape is
Since the track pattern recorded on a magnetic tape running at a predetermined running speed in correspondence with the rotation locus of a rotating magnetic head will be different, magnetic tapes with information signals recorded by this method If the disc is played back while running at a predetermined running speed, the rotating magnetic head cannot accurately track the track.
It is also possible to record and use the same magnetic tape in such a way that the tracks recorded by this method (■) and the tracks recorded on the magnetic tape while running at a predetermined speed are mixed. It is difficult to do so.

FIG. 14 shows a VTR equipped with a drum assembly DA constituted by a rotating drum Dr and a fixed drum Df provided as a pair with the rotating drum Dr.
It is a perspective view showing a schematic structure of a mechanical part of
FIG. 15 shows a track pattern recorded and formed on a magnetic tape running at a predetermined running speed in correspondence with the rotation locus of a rotating magnetic head, and a track pattern recorded on a magnetic tape running at a predetermined running speed, and a track pattern recorded on a magnetic tape running at a predetermined running speed, and a track pattern recorded on a magnetic tape running at a predetermined running speed, and a track pattern recorded on a magnetic tape running at a predetermined running speed. FIG. 16 shows a drum assembly DA constituted by a rotating drum Dr and a fixed drum Df provided as a pair with the rotating drum Dr. The general structure of the surrounding area, the recording traces formed in correspondence with the rotation locus of the rotating magnetic head on the magnetic tape running at a predetermined running speed, and the magnetic tape in a state where the recording operation is stopped. FIG. 3 is a diagram for explaining changes in a recording trace formed in correspondence with a rotation locus of a rotating magnetic head. In the figure, DA is the rotating drum Dr.
and a fixed drum Df provided as a pair with the rotating drum Dr, a drum structure Ha.
, Hb is a rotating magnetic head, T is a magnetic tape, Te is a reference edge of the magnetic tape T, 1 is a supply reel stand, 2 is a take-up reel stand, 3 and 4 are inclined guides (slant poles), 5 and 6
is a guide roller, 7 is an impedance roller, 8 is a capstan, 9 is a pinch roller, 10 is a full width erasing head,
11 is an audio head and a control head, 12 is a rotating shaft, arrow a in the figure indicates the rotation direction of the rotating drum Dr, and arrow b indicates the moving direction of the magnetic tape T.

[0006] The rotating drum Dr has a predetermined rotation speed N.
s to rotate in the direction of arrow a, and the magnetic tape T is moved in sliding contact with a part of the circumferential surface of the rotating drum Dr at a predetermined running speed V in the direction of arrow b.
s, the magnetic tape T records individual recordings of length Ls, as illustrated in FIG. Traces Tra and Trb are formed, and at this time, the angle between the extending direction of each of the recording traces Tra and Trb and the reference edge Te of the magnetic tape T represents an angle θs. Next, the rotating drum Dr of the drum assembly DA in the figure is rotated in the direction of the arrow a at a predetermined number of rotations Ns, and the magnetic tape T that is in sliding contact with a part of the circumferential surface of the rotating drum Dr is rotated. When the rotating magnetic heads Ha,
The recording trace formed on the magnetic tape T by the rotation locus of time Ts of Hb, for example, in the case of the recording trace by the rotating magnetic head Hb, is the recording trace Trbo shown by dots surrounded by a broken line frame in FIG. It will be shown as,
This recording trace Trbo indicates that the magnetic tape T is running at a predetermined running speed V.
This corresponds to the recording trace Trb in FIG. 15 that is formed on the magnetic tape T while the magnetic tape T is running at speed s, but the aforementioned recording trace Trbo that is formed when the magnetic tape T is stopped has a length of Lo and the angle between the direction in which the recording trace Trbo extends and the reference edge Te of the magnetic tape T indicates the angle θo. Here, the magnetic tape is V
The inclination angles θs and θo of the recording trace when the device is configured so that it can be continuously reproduced by a magnetic recording and reproducing device (VTR) operating in standard mode in the HS (registered trademark) system, and various aspects of the VHS (registered trademark) system. The main standards are listed below for reference. Video track angle when magnetic tape T runs (
The inclination angle θs of the recorded trace mentioned above)...5°58'9.9",
Video track angle when the magnetic tape T is stopped (the inclination angle θo of the recording trace mentioned above)...5°56'7.4" Rotating drum diameter...62 mm ± 10 μm, Rotating drum rotation speed Ns...1800 revolutions per minute, Magnetic tape feeding speed...33.35mm/sec ±0.5%,

00
In the example shown in FIG. 15, since the rotational direction (moving direction) a of the rotating magnetic heads Ha and Hb and the moving direction b of the magnetic tape are the same, the magnetic tape T is formed at the same time. Regarding the length of the recording trace due to the rotation trajectory of the rotary head, the length of the recording trace L when the magnetic tape T is running is longer than the length Lo of the recording trace when the magnetic tape T is stopped, that is, Ls<Lo. , and the angle between the direction in which the recording trace extends and the reference edge Te of the magnetic tape T is the angle θs between the direction in which the recording trace extends and the reference edge Te of the magnetic tape T when the magnetic tape T is running. is larger than the angle θo formed between the direction in which the recording trace extends when the magnetic tape T is stopped and the reference edge Te of the magnetic tape T, that is, θo<θs. In this way, a track pattern is recorded on a magnetic tape running at a predetermined running speed in correspondence with the rotation locus of a rotating magnetic head, and a track pattern is recorded on a magnetic tape running at a predetermined running speed, and a track pattern is recorded on a magnetic tape running at a predetermined running speed. The track pattern recorded and formed in correspondence with the locus will be different.

[0008] In order to solve the problems in the prior art mentioned above as ① and ②, conventionally, for example, recording is formed on a magnetic tape running at a predetermined running speed in correspondence with the rotation locus of a rotating magnetic head. A recording trace of the information signal similar to the recording trace of the information signal is recorded and formed by the rotation locus of the rotating magnetic head relative to the magnetic tape in a state in which the magnetic tape is stopped after intermittently moving by a predetermined distance in the tape running direction. The rotation trajectory of the rotary magnetic head during the intermittent recording operation is controlled based on the position signal of the rotary magnetic head generated in correspondence with the absolute position of the rotary magnetic head with respect to the tape reference edge of the magnetic tape. In a VTR equipped with an actuator, for example, as disclosed in Japanese Utility Model Publication No. 63-34126, the magnetic tape runs at a standard running speed and the magnetic tape runs at a running speed other than the standard running speed. In this case, the inclination angle of the drum shaft is changed while the position of the reference edge of the magnetic tape at the center of the winding angle of the magnetic tape on the drum does not change, so that the magnetic tape runs at the standard running speed. For example, in a VTR, which is capable of tracking and reproducing the recording traces that were recorded on the magnetic tape by a rotating magnetic head when the magnetic tape T was in use, the inclination angle θo of the recording trace when the magnetic tape T is stopped is It has been considered to change the rotational locus of the rotary magnetic head so that it becomes equal to the inclination angle θs of the recording trace during running.

[0009]

[Problems to be Solved by the Invention] However, in a VTR that uses an actuator to control the rotational trajectory of the rotating magnetic head during intermittent recording operation as described above, it is difficult to control the rotational trajectory of the rotating magnetic head. Since the actuator must be installed in a narrow space within the rotating drum, a small actuator is required, but the small actuator cannot apply a relatively large displacement to the rotating magnetic head. At the same time, the rotating magnetic head that is displaced by the actuator must be constructed so that the state of the head's contact with the magnetic tape will not deteriorate even when the head is displaced, and it is difficult to position the rotating magnetic head during recording. For these reasons, it is difficult to construct a VTR that performs good recording and reproducing operations using a small actuator that exhibits good operating characteristics. ,
The problem is that the reference edge of the magnetic tape is not guided stably and can only be used during playback operations. As mentioned above, a VTR can be used as a component of a digital information processing device, for example, as an "external auxiliary storage device for a computer",
Functions required when used in devices such as "devices that record computer graphics images sequentially at the end of calculations and continuously reproduce them to create moving images," i.e., recording information signals on magnetic tape. As a VTR that can perform recording operations in units of one recording trace (1 track) to several tracks with high stability and reliability, it is suitable for home use. If it could be realized using equipment comparable to an inexpensive VTR, it would have great utility value, such as making it possible to easily produce animation works at home, for example.

0010

[Means for Solving the Problems] The present invention provides a magnetic tape running at a predetermined speed Vs while slidingly contacting a part of the circumferential surface of a drum, and a magnetic tape running on a part of the circumferential surface of the drum. In either case, the position of the reference edge of the magnetic tape at the center of the wrapping angle of the magnetic tape with respect to the drum is maintained substantially the same with respect to the magnetic tape in sliding contact with the magnetic tape in a stopped state. In this state, a recording mark formed on the magnetic tape by a rotating magnetic head rotating at a predetermined number of revolutions Ns is such that the reference edge of the magnetic tape and the extending direction of the recording trace are at a predetermined angle θs. a guide portion having a predetermined length in the direction in which the reference edge of the magnetic tape extends, so as to be formed on the magnetic tape in response to the switching change of the running speed of the magnetic tape at an angle; The position of the reference edge of the magnetic tape in sliding contact with the circumferential surface of the drum is determined by the magnetic tape guiding means constituted by both the lower drum and the member loosely fitted on the circumferential surface of the lower drum. A magnetic recording/reproducing device configured to perform switching, a magnetic tape running at a predetermined speed Vs while sliding on a part of the circumferential surface of the drum, and a magnetic tape running on a part of the circumferential surface of the drum. The position of the reference edge of the magnetic tape at the center of the wrapping angle of the magnetic tape with respect to the drum remains substantially the same in both cases with the magnetic tape in sliding contact with the magnetic tape in a stopped state. In the state where the recording mark is formed on the magnetic tape by the rotating magnetic head rotating at a predetermined number of revolutions Ns, the reference edge of the magnetic tape and the extending direction of the recording trace are at a predetermined angle θs. The reference edge of the magnetic tape is formed on the magnetic tape in response to the change in the running speed of the magnetic tape, so that the reference edge of the magnetic tape is formed on the magnetic tape in response to the change in the running speed of the magnetic tape. The magnetic recording and reproducing device is configured to change the position of the magnetic tape during running of the magnetic tape on one end surface of an annular body that is rotatably fitted to the circumferential surface of the lower drum. The guide part for the reference edge of the tape and the guide part for the reference edge of the magnetic tape when the magnetic tape is stopped are configured sequentially in the circumferential direction, and the above-described annular shape is formed in correspondence with the change in the running speed of the magnetic tape. By rotating the body in the circumferential direction, a predetermined one of the guide parts for the reference edge of the magnetic tape formed on one end surface of the annular body is selected and used for guiding the reference edge of the magnetic tape. a magnetic recording and reproducing device comprising a means for making the tape move at a predetermined speed Vs while slidingly contacting a part of the circumferential surface of the drum; and a part of the circumferential surface of the drum. In both cases, the magnetic tape is brought into sliding contact with the magnetic tape while its running is stopped.
While the position of the reference edge of the magnetic tape at the center of the wrapping angle of the magnetic tape on the drum is maintained substantially the same, the magnetic tape is The recording trace formed on the magnetic tape is changed in response to the change in the running speed of the magnetic tape described above, with the reference edge of the magnetic tape and the extending direction of the recording trace being at a predetermined angle θs. A magnetic recording and reproducing apparatus is configured such that the position of the reference edge of the magnetic tape is changed in response to the change in the running speed of the magnetic tape, the peripheral surface of the lower drum being formed as follows. The guide portion for the reference edge of the magnetic tape when the magnetic tape is running as described above and the guide portion for the reference edge of the magnetic tape when the magnetic tape is stopped are configured sequentially in the circumferential direction, and the above-described running speed of the magnetic tape is In response to the switching change, the lower drum is rotated in the circumferential direction, and a predetermined one of the guide parts for the reference edge of the magnetic tape formed in the lower drum is aligned with the reference edge of the magnetic tape. A magnetic recording and reproducing device comprising a means for selectively using the magnetic tape for guiding, and a magnetic tape running at a predetermined speed Vs while slidingly contacting a part of the circumferential surface of the drum; In both cases, the reference edge of the magnetic tape at the center of the winding angle of the magnetic tape with respect to the drum, in both cases where the magnetic tape is in sliding contact with a part of the circumferential surface of the drum while it is stopped running. While the position of the magnetic tape is maintained substantially the same, the recording mark formed on the magnetic tape by the rotating magnetic head rotating at a predetermined rotation speed Ns is aligned with the reference edge of the magnetic tape and the recording trace. Switching and changing the running speed of the magnetic tape so that the magnetic tape is formed on the magnetic tape in accordance with the switching and changing of the running speed of the magnetic tape in a state where the extension direction is at a predetermined angle θs. This magnetic recording and reproducing device is configured to switch and change the position of a reference edge of a magnetic tape in response to the change in position, and the magnetic tape is supported by a swinging fulcrum provided at the center of the winding angle of the magnetic tape with respect to the lower drum. The annular body is loosely fitted around the lower drum so that it can swing freely.
A first swinging position in which one end face of the magnetic tape is in a swinging displacement state where it can be used as a guide for the reference edge of the magnetic tape when the magnetic tape is running, and a first swinging position when the magnetic tape is stopped. The second oscillating position is such that it can be used as a guide for the reference edge of the magnetic tape, and is switched to a second oscillating position in response to the above-mentioned change in running speed of the magnetic tape. a magnetic recording/reproducing device comprising a means for driving the magnetic tape to a predetermined speed Vs while slidingly contacting a part of the circumferential surface of the drum; In both cases, the position of the reference edge of the magnetic tape at the center of the wrapping angle of the magnetic tape with respect to the drum is substantially the same for both magnetic tapes that are brought into sliding contact with the magnetic tape in a state where the running is stopped. In the held state, a recording mark is formed on the magnetic tape by a rotating magnetic head rotating at a predetermined number of revolutions Ns. The standard of the magnetic tape is formed on the magnetic tape in response to the above-mentioned change in the running speed of the magnetic tape in a state where the angle θs is changed. A magnetic recording and reproducing device in which the position of the edge is switched and changed, and the magnetic tape is placed in the vicinity of the part where the reference edge of the magnetic tape is located in the part of the outer peripheral surface where the magnetic tape is in sliding contact with the lower drum. , a first edge shape corresponding to a guide portion of a reference edge of the magnetic tape during running of the magnetic tape is provided on at least a portion of one side of the lower drum with respect to the central portion of the wrapping angle of the magnetic tape as a boundary; ,
A small-diameter portion is formed on the lower drum in such a manner that a second edge shape corresponding to the guide portion of the reference edge of the magnetic tape when the magnetic tape is stopped is formed on at least a portion of the other side. The magnetic tape is also supported by a swinging fulcrum provided at the center of the wrapping angle of the magnetic tape on the lower drum, and is loosely fitted around the circumferential surface of the small diameter portion of the lower drum. One end surface of the annular body is moved to the position of the end surface portion of the guide portion of the reference edge of the magnetic tape having the above-described first edge shape in the lower drum in accordance with the switching change of the running speed of the magnetic tape. and the position of the end face portion of the guide portion of the reference edge of the magnetic tape having the second edge shape. do.

[0011]

[Operation] The rotating magnetic head Ha(
Hb) forms a recording trace Tra (Trb) whose angle with the reference edge Te of the magnetic tape T is an angle θs. A rotary magnetic head Ha (Hb) rotating at a predetermined number of rotations Ns is applied to the magnetic tape T in sliding contact with the magnetic tape T so that the angle formed by the reference edge Te of the magnetic tape T is an angle θs. A recording trace is recorded on the magnetic tape T at the center of the wrapping angle of the magnetic tape T on the drum.
The position of the reference edge Te of the magnetic tape T corresponds to the switching change of the running speed of the magnetic tape T so that the position of the reference edge Te of the magnetic tape T is formed on the magnetic tape T in a state where the position of the reference edge Te of the magnetic tape T is maintained substantially the same. The magnetic tape T is stably switched and changed using a component shaped along the reference edge Te of the magnetic tape T.

0012

DESCRIPTION OF THE PREFERRED EMBODIMENTS The specific contents of the magnetic recording and reproducing apparatus of the present invention will be explained in detail below with reference to the accompanying drawings. FIG. 1 is a perspective view of one embodiment of the magnetic recording and reproducing apparatus of the present invention, FIG. 2 is an exploded perspective view of the magnetic recording and reproducing apparatus of the present invention shown in FIG. 1 is a schematic side view used to explain the configuration of main parts of a magnetic recording/reproducing apparatus of the present invention. In the figure, DA is a drum structure, and this drum structure DA is assembled by a drum base DB, a rotating drum Dr, a lower drum Df, a motor M, and the like. An annular guide member 31 having a structure as clearly shown in FIG. 2 is fitted onto the lower circumferential surface of the lower drum attached to the drum base DB. The annular guide member 31 has guide surfaces 31s and 31o for guiding the reference edge Te of the magnetic tape T on one end surface of the annular guide member 31, each having a half circumference, and a guide surface 31s and 31o on the other end surface thereof. The spur gear 30 is configured over half a circumference or more. The surface 31a of the annular guide member 31 moves the annular guide member 31 toward the lower drum Df while the back surface of the spur gear 30 is in pressure contact with the reference surface 22 provided on the drum base DB. In order to enable stable rotation around the
This is a groove portion into which the tip of the holder slides. The above-described pressure spring 23
, 28 are individually fixed to the drum base DB by screws 25 or 27, respectively. Reference numeral 26 shown in FIG. 2 is a screw hole used when fixing the above-described pressure spring 23 to the drum base DB with a screw 25.

After the annular guide member 31 is rotatably attached around the lower drum Df, the rotation shaft of the rotational drive motor 34 is connected to the spur gear 30 formed on the annular guide member 31 described above. After meshing the spur gear 32 fixed to the drum base DB, the rotary drive motor 34 is fixed to the wall 36 of the drum base DB using, for example, a mounting band 35 and screws 37. If a stepping motor is used as the rotation drive motor 34, the rotation position of the annular guide member 31 can be easily controlled. The rotational drive motor 34
A geared motor may also be used. The protrusion 13 of the lower drum Df and the rotating drum D shown in FIG.
After fitting the openings 17 of r, align the screw holes 15, 16 provided in the lower drum Df with the screw holes 18, 19 provided in the rotating drum Dr, and then screw the screws 20, 2.
1, the lower drum Df and the rotating drum (upper drum) Dr are connected.

Which guide surface of the two types of guide surfaces 31s and 31o described above for guiding the reference edge Te of the magnetic tape T provided on one end surface of the annular guide member 31 is the magnetic tape. Whether it is used for the guiding action with respect to the reference edge Te of T is determined by the operation mode set by the operator to an operation section (not shown) in the magnetic recording/reproducing apparatus. When the operation mode set by the operator on the operation section is a normal recording/playback mode, a control circuit (not shown) rotates the rotary drive motor 34 in the forward direction. The spur gear 30 is controlled to mesh with the spur gear 32 fixed to the rotation shaft 33 of the rotational drive motor 34.
The annular guide member 31 provided with the lower drum Df
By rotating the magnetic tape T by 180 degrees, the reference edge Te of the magnetic tape T is positioned at the position where the reference edge Te of the magnetic tape T must be located when the magnetic recording/reproducing apparatus operates in the normal recording/reproducing mode. In this state, the reference edge Te of the magnetic tape T is rotated to a position where it can be guided by the guide surface 31s.

Furthermore, when the operation mode set by the operator on the operation section is a recording/reproducing mode (still recording/reproducing mode) in which running of the magnetic tape is stopped, a control circuit (not shown) is activated. controls the rotary drive motor 34 to rotate in the opposite direction, and the rotary drive motor 34
By rotating the annular guide member 31, which is provided with a spur gear 30 that meshes with a spur gear 32 fixed to a rotating shaft 33, by 180 degrees around the lower drum Df, the magnetic recording/reproducing device The reference edge T of the magnetic tape T when operating in the recording/playback mode with the tape stopped running.
The reference edge Te of the magnetic tape T is located at the position where the reference edge Te of the magnetic tape T should be located.
is rotated to a position where it can be guided by the guide surface 31o. That is, the annular guide member 31, which is rotatably provided around the lower drum Df and is driven by the rotary drive motor 34 to perform rotary movements, is not shown. The annular guide member 3 is driven and rotated in both forward and reverse directions by the control operation of the control circuit performed in accordance with the operation mode set by the operator on the operation section that is not connected to the rotary drive motor 34.
1 is selectively rotated 180 degrees in both forward and reverse directions,
The reference edge T of the magnetic tape T is formed at each approximately half-circumference portion of one end surface of the annular guide member 31.
The guide surface 31s, 31o for guiding the magnetic tape T can be switched to a state in which a guiding action to the reference edge Te of the magnetic tape T is selectively performed.

Now, in a magnetic recording and reproducing apparatus equipped with a magnetic tape running system as already described with reference to FIG. 14, the magnetic tape T during recording and reproducing operation is
), the magnetic tape T is wound around the drum at a wrapping angle slightly larger than 180 degrees (approximately 10 degrees), and the wrapping angle of the magnetic tape T around the drum mentioned above is Reference surface SF of the reference edge Te of the magnetic tape T at the center (position indicated by P90 in the figure)
The height H90 from {see FIG. 16(d)} is the height H90 of the magnetic tape T whose height position is correctly regulated by the guide rollers 5 and 6 also shown in FIG. 16(a). The position of the reference edge Te is the same as that of the reference edge Te, and the inclination angle of the drum and the inclination guide 3 are adjusted to prevent expansion and contraction of the parts of the magnetic tape T that are in sliding contact with the circumferential surface of the drum in this state. , 4, etc. are set. By the way, as shown in FIG. 15, for example, the rotational direction a of the rotating magnetic heads Ha and Hb and the moving direction b of the magnetic tape T
are the same, the recording marks formed on the magnetic tape by a rotating magnetic head rotating at a predetermined number of rotations Ns while the magnetic tape T is running at a predetermined speed Vs. An angle θs formed between the extending direction and the reference edge Te of the magnetic tape T, and a rotating magnetic head rotating at a predetermined number of rotations Ns while the magnetic tape T is stopped. Angle θ between the direction in which the recording trace extends and the reference edge Te of the magnetic tape T
Since θo<θs, there is a relationship between the recording traces formed by the rotating magnetic head on the running magnetic tape T and the recording traces formed by the rotating magnetic head on the stopped magnetic tape T. In order to make the angle between the extending direction of the recording trace and the reference edge Te of the magnetic tape T the same, it is necessary to
and the position Tes of the reference edge Te of the magnetic tape T in the stopped state.
The position Teo of the reference edge Te of the magnetic tape T at
Lines T shown in (c) and (d) of FIG. 16, respectively
es, Teo, the angle with respect to the reference plane SF is θo
It is necessary to change θs to θs. When the difference between the two angles θs and θo is small, as in the case of the VHS (registered trademark) system described above, the center of the wrapping angle of the magnetic tape T on the drum is Reference surface SF of the reference edge Te of the magnetic tape T at the position (position indicated by P90 in the figure) {see (d) in FIG. 16}
By simply ensuring that the height H90 from the drum does not change, even when the position of the reference edge Te of the magnetic tape T is switched between the two modes as described above, each part of the magnetic tape T that is in sliding contact with the drum can be It is possible to prevent the application of force that would cause expansion and contraction.

In the embodiment of the magnetic recording/reproducing apparatus of the present invention shown in FIGS. 1 to 3, an annular guide member 31 is rotatably fitted to the outer circumference of the lower drum Df.
The guide surfaces 31s and 31o for guiding the reference edge Te of the magnetic tape T formed on one end surface thereof are recording marks formed by the rotating magnetic head on the running magnetic tape T as described above. and the recording trace formed by the rotating magnetic head on the magnetic tape T in the stopped state. The position Tes of the reference edge Te of the magnetic tape T at T and the reference edge Te of the magnetic tape T in the stopped state of the magnetic tape T
The position Teo is set to the reference plane SF as lines Tes and Teo shown in FIGS.
It is formed so that the angle with respect to it can be changed to θo and θs. Further, depending on the operating mode of the magnetic recording/reproducing device, the annular guide member 31 rotatably fitted to the outer circumference of the lower drum Df can be rotated by 180 degrees in either the forward or reverse direction as described above. Rotate the guide surface (3
1s, 31o) is selectively used,
The reference surface S corresponds to the central portion of the guide surface described above, that is, the central portion of the wrapping angle of the magnetic tape T to the drum.
The above-mentioned annular guide member 31 is held in a fixed state with the part whose height from F is H90 positioned accurately at position P90 of the center of the winding angle of the magnetic tape T on the drum. However, in doing so, the rotation angle of the annular guide member 31 and the information detected by the absolute amount of movement of the annular guide member 31 are given to the control circuit to control the rotation of the annular guide member 31. This can be easily done by controlling the amount of movement and rotation position.

In the magnetic recording and reproducing apparatus described above with reference to FIGS. 1 to 3, as is particularly clear from the exploded perspective view shown in FIG. 2, two types of guide surfaces 31s and 31
An annular guide member 31 is provided on each end of the lower drum Df, and a spur gear 30 is formed on the other end surface over a half circumference or more. Rotatably fit around the circumferential surface of the
With the annular guide member 31 pressed against the reference surface 22 provided on the drum base DB, the annular guide member 31 is moved around the lower drum Df in accordance with the operating mode of the magnetic recording/reproducing device. , the guide surface (one of 31s and 31o) required by the operation mode set in the magnetic recording and reproducing device is selected and used by rotating it by 180 degrees in either the forward or reverse direction. However, in the magnetic recording and reproducing apparatus of the present invention shown in FIGS. 4 and 5, the operation mode in which the magnetic tape is running is the normal recording and reproducing mode (normal recording and reproducing mode). ) and in the recording/reproducing mode with the magnetic tape stopped running (still recording/reproducing mode), the reference edge Te of the magnetic tape T must be positioned at the respective position. Reference edge T of magnetic tape T
Two types of guide surfaces 39s for positioning e
, 39o are constructed directly on the outer peripheral surface of the lower drum Df.

FIG. 4(a) is an overall perspective view, and FIG. 4(b) is an overall perspective view.
) is a guide surface 39s formed on the outer periphery of the lower drum Df,
FIG. 5 is a side view for explaining 39o, and FIG.
FIG. 2 is an exploded perspective view of the magnetic recording/reproducing device shown in FIG. Two types of guide surfaces 39s and 39o are respectively formed by cutting, for example, in successive portions of the outer circumferential portion of the lower drum Df, each approximately half a circumference apart. With reference to FIG. 5, on the end surface 40 of the lower drum Df described above,
The peripheral surface of the opening of the spur gear plate 38 is fitted to the outer peripheral surface of the stepped portion 52 of the lower drum Df so that the lower surface of the spur gear plate 38 is brought into contact with the lower surface of the lower drum Df. After aligning the provided screw holes 41, 42, 43... with the screw holes 44, 45, 46, 47 drilled in the spur gear plate 38,
The lower drum Df and the spur gear plate 38 are fixed using screws 48, 49, 50, and 51 to integrate the two. In addition, in the case of the illustrated configuration example, the spur gear plate 38 has gear teeth cut over an area slightly wider than half its circumference. The outer peripheral surface of the engaging portion 72 of the lower drum Df with the spur gear plate 38 fixed to the end surface 40 as described above is fitted into the inner peripheral surface of the opening 124 of the drum base DB, and then the stepped portion 52 is fitted. After the surface is brought into contact with the sliding surface configured on the drum base DB, the hole 6 of the holding plate 55 is opened.
3 is loosely fitted into the center part 62 of the lower drum, and this holding plate 55 is
Align the screw holes 58, 59, 60, 61 drilled in the lower drum with the screw holes 55, 56, 57, . . . of the engaging portion 72 of the lower drum. Next, after attaching individual spring washers 68, 69, 70, 71 to the screws 64, 65, 66, 67, respectively, the screw holes 58, 59 of the above-described holding plate 55 and the screw holes 55 of the lower drum Df, 56...Screw into. As a result, the drum assembly DA consisting of the rotating drum Dr and the lower drum Df is rotatable with the surface of the stepped portion 52 of the lower drum Df in contact with the sliding surface formed on the drum base DB. It will be combined with the drum base DB.

Spur gear plate 38 attached to lower drum Df
After meshing the spur gear 32 fixed to the rotating shaft of the rotational drive motor 34, the rotational drive motor 34
is fixed to the wall portion 36 of the drum base DB using, for example, a mounting band 35 and screws 37. If a stepping motor is used as the rotation drive motor 34, the rotation position of the annular guide member 31 can be easily controlled. Also,
A geared motor may be used as the rotation drive motor 34. In the embodiment illustrated in FIGS. 4 and 5, two types of guide surfaces 39s and 39o are formed by cutting, for example, on successive approximately half-circumferential portions of the outer circumferential portion of the lower drum Df. However, in order to configure the two types of guide surfaces 39s and 39o described above on the outer circumferential surface of the lower drum Df, it is necessary to attach a band-shaped guide member to the outer circumferential surface of the lower drum Df, for example by screwing. It may also be configured to be attached by a fixing means such as.

Which of the two types of guide surfaces 39s and 39o formed on the outer peripheral surface of the lower drum Df is used for guiding the reference edge Te of the magnetic tape T? , as in the case of the magnetic recording/reproducing apparatus already described with reference to FIGS. 1 to 3, is determined by the operation mode set by the operator on the operation unit (not shown). When the operation mode is a normal recording/reproducing mode, a control circuit (not shown) controls the rotary drive motor 34 to rotate in the forward direction. When the magnetic recording and reproducing device operates in the normal recording and reproducing mode by rotating the lower drum Df by 180 degrees to which the spur gear plate 38 that meshes with the spur gear 32 that is secured to the rotating shaft 33 of the magnetic recording and reproducing apparatus is fixed. The reference edge Te of the magnetic tape T is located at the position where the reference edge Te of the magnetic tape T must be located, and the reference edge Te of the magnetic tape T is placed in a position where it can be guided by the guide surface 39s. Rotate until.

Furthermore, when the operation mode set by the operator on the operation section is a recording/reproducing mode in which running of the magnetic tape is stopped (still recording/reproducing mode), a control circuit (not shown) is activated. controls the rotary drive motor 34 to rotate in the opposite direction, and the rotary drive motor 34
A state in which the magnetic recording and reproducing device stops running the magnetic tape by rotating the lower drum Df by 180 degrees to which the spur gear plate 38 that meshes with the spur gear 32 which is fixed to the rotating shaft 33 of the magnetic recording/reproducing device is fixed. When the reference edge Te of the magnetic tape T is located at the position where the reference edge Te of the magnetic tape T must be located when operating in the recording/reproducing mode in Rotate it to a position where it can be guided by. In other words, the drum assembly DA is driven by the rotary drive motor 34 to perform rotary movements.
The magnetic tape T is guided by one of two types of guide surfaces 39s and 39o for guiding the reference edge Te of the magnetic tape T, each of which is formed at a portion of the outer periphery of the lower drum Df about half a circumference. The guide action for the reference edge Te is selectively performed, and the selection of the guide surface is rotationally driven by a control operation of a control circuit performed in accordance with an operation mode set by the operator on an operation section (not shown). This is done by driving and rotating the motor 34 in both the forward and reverse directions, thereby selectively rotating the drum assembly DA by 180 degrees in both the forward and reverse directions.

Also in the magnetic recording/reproducing apparatus shown in FIGS. 4 and 5, the magnetic tape T is located at the center of the wrapping angle on the drum (the position indicated by P90 in the drawings). Reference surface S of reference edge Te of tape T
The height H90 from F {see (d) in FIG. 16} is as shown in FIG.
Magnetic tape T whose height position is correctly regulated by guide rollers 5 and 6 also shown in (a) of
The inclination angle of the drum and the inclination guide are adjusted so that the position of the reference edge Te is the same as that of the reference edge Te in this state, and the inclination angle of the drum and the inclination guide Inclination angles of 3 and 4 are set. Then, the magnetic tape T in the running state of the magnetic tape T
and the position Tes of the reference edge Te of the magnetic tape T in the stopped state.
The position Teo of the reference edge Te of the magnetic tape T in is
Lines T shown in (c) and (d) of FIG. 16, respectively
es, Teo, the angle with respect to the reference plane SF is θo
and θs, but the already mentioned VHS (registered trademark)
As in the example of the method, the two angles θs and θ
If the difference in angle from the angle with o is small, the reference surface SF of the reference edge Te of the magnetic tape T at the center of the wrapping angle of the magnetic tape T on the drum (the position indicated by P90 in the figure) By simply keeping the height H90 from {see FIG. 16(d)} unchanged, even when the position of the reference edge Te of the magnetic tape T is switched between two modes, the magnetic field in sliding contact with the drum can be It is possible to prevent the application of force that would cause expansion and contraction to each part of the tape T.

In the embodiment of the magnetic recording/reproducing apparatus of the present invention shown in FIGS. 4 and 5, a guide surface for guiding the reference edge Te of the magnetic tape T is formed on the outer circumference of the lower drum Df. 39s and 39o are extensions of the recording traces formed by the rotating magnetic head on the running magnetic tape T and the recording traces formed by the rotating magnetic head on the stopped magnetic tape T as described above. The position Tes of the reference edge Te of the magnetic tape T in the running state and the position Tes of the reference edge Te of the magnetic tape T in the stopped state so that the direction and the angle formed by the reference edge Te of the magnetic tape T are the same are Position Te of reference edge Te
16 (c) and (d), respectively, the angles with respect to the reference plane SF can be changed to θo and θs. Also, depending on the operating mode of the magnetic recording/reproducing device,
Move the lower drum Df 180 degrees in either the forward or reverse direction as described above.
Rotate only the guide surface (39s, 39o) required by the operating mode set in the magnetic recording/reproducing device.
When one of the following is selected and used, the height from the reference plane SF corresponds to the central part of the guide surface described above, that is, the central part of the wrapping angle of the magnetic tape T around the drum. It is necessary that the aforementioned lower drum Df be held in a fixed state with the portion formed at H90 being accurately positioned at position P90 of the center of the winding angle of the magnetic tape T on the drum. However, this can be easily done by feeding the detected information such as the rotation angle and absolute amount of movement of the lower drum Df to the control circuit and controlling the rotation amount and rotation position of the lower drum Df. Needless to say, it can be done.

The guide surfaces 31s and 31o in the embodiment described with reference to FIGS. 1 to 3 and the guide surfaces 39s and 3 in the embodiment described with reference to FIGS. 4 and 5
The inclination angle that each guide surface such as 9o shows with respect to the reference surface SF of the drum base DB is as shown in (c) and () in FIG.
d) by the lines Tes and Teo respectively shown in FIG. That is, when the operation mode of the magnetic recording and reproducing device is the normal recording and reproducing mode, the inclination angle that the guide surfaces 31s and 39s have with respect to the reference surface SF of the drum base DB is θ.
o, and when the operating mode of the magnetic recording/reproducing apparatus is a recording/reproducing mode (still recording/reproducing mode) in which running of the magnetic tape is stopped, the guide surfaces 31o, 39o described above are Drum base DB reference plane S
The angle of inclination shown with respect to F is made θs.

Next, the overall perspective view of FIG. 6(a) and FIG.
An embodiment of the magnetic recording/reproducing apparatus of the present invention shown in FIG. 7(b) is a side view of the main part, and FIG. 7 is an exploded perspective view. In the magnetic recording and reproducing apparatuses of the embodiments already described with reference to FIGS. 1 to 5, there is provided a guide surface for guiding the reference edge Te of the magnetic tape when the magnetic tape is running, and a guide surface for guiding the reference edge Te of the magnetic tape when the magnetic tape is stopped. Reference edge Te of magnetic tape
Switching between the guiding surface and the guiding surface was performed by rotating the aforementioned guiding surface in the circumferential direction of the drum. However, in the magnetic recording and reproducing apparatus shown in FIGS. 6 and 7, When the magnetic tape runs, the reference edge Te of the magnetic tape
A guide surface for guiding the magnetic tape and a switch for changing the position of the guide surface for guiding the reference edge Te of the magnetic tape when the magnetic tape is stopped are swingably provided on the outer periphery of the lower drum Df in the drum assembly DA. This is performed by a swinging guide member 72.

The swing guide member 72 described above has a shape that appears as a ring when it is shown in a top view, and this swing guide member 72 is shown in FIG. As shown in the figure, an inclined surface 72u formed at a constant inclination angle of 180 degrees or more is provided on one end surface of the magnetic tape T as a part used as a guide surface for the reference edge Te of the magnetic tape T. In addition, one of the two swing fulcrums for swingably supporting the swing guide member 72 with respect to the lower drum Df is located on the side surface corresponding to the center of the inclined surface 72u. A hole 77 is bored into which a screw 73, which is used as a pivot point, is fitted. Reference numeral 78 denotes a hole bored in the side surface of the swing guide member 72 at a position 180 degrees symmetrical to the hole 77.
A screw 74, which is used as the other swing fulcrum, is fitted into. After the swing guide member 72 is loosely fitted to the outer periphery of the lower drum Df, the screw 73 fitted into the hole 77 on the side surface of the swing guide member 72 is inserted into the screw hole 7 provided in the lower drum Df.
9 and also screws the screw 74 fitted into the hole 78 on the side surface of the swing guide member 72 into a screw hole (not shown) provided in the lower drum Df. It is supported in a swingable manner on the outer periphery of Df. Reference numerals 80 and 81 are holes drilled in the lower drum Df, and pins 76 and 75 are installed in these holes 80 and 81, respectively. The swing guide member 72, which is swingably supported by the lower drum Df as described above, is connected to the hole 8 provided in the lower drum Df.
The pins 76 and 75 installed at 0 and 81 limit the range of their swinging displacement.

That is, the swing guide member 72 is swingably provided on the outer periphery of the lower drum Df by means of two swing supporting points 73 and 74 provided at 180 degree symmetrical positions on the outer periphery of the lower drum Df. Although the rocking displacement about the rocking fulcrums 73 and 74 is possible only between the two pins 75 and 76 implanted in the lower drum Df, the rocking guide described above is The position of the inclined surface 72u in the swing guide member 72 shown in solid line in FIG. 72s corresponds to a guide surface for guiding the reference edge Te of the magnetic tape during running of the magnetic tape, and also shows a state in which the lower surface of the swing guide member 72 is in contact with the pin 75. When the magnetic tape is stopped, the position 72o of the inclined surface 72u in the swing guide member 72 shown by the dotted line in FIG.
By setting the installation positions of the two pins 75 and 76 so as to correspond to the guide surface for guiding the magnetic tape T, the magnetic tape T can be moved at the running speed in the normal recording/reproducing mode. In the traveling state, the upper surface of the swing guide member 72 (in the illustrated embodiment, the notch 72
The swing guide member 72 is swing-displaced so that the bottom surface of the magnetic tape T is in contact with the pin 76.
When the above-mentioned swing guide member 7 is stopped, the swing guide member 7
Simply by oscillatingly displacing the oscillating guide member 72 so that the lower surface of 2 is in contact with the pin 75, the magnetic tape T is running at the running speed in the normal recording/reproducing mode. In both cases, when the magnetic tape T is in a stopped state, the swing guide member 72
The reference edge Te of the magnetic tape can be guided by the inclined surface 72u of the swing guide member 72 with the inclined surface 72u set at the correct position required in each case. . The position 72s of the inclined surface 72u in the swinging guide member 72 shown in solid line in FIG. It has an inclination of θo with respect to the reference surface SF of the base DB, and also corresponds to a guide surface for guiding the reference edge Te of the magnetic tape when the magnetic tape is stopped.
The position 72o of the inclined surface 72u in the swing guide member 72 shown by the dotted line in (b) has an inclination of θs with respect to the reference plane SF of the drum base DB.

By oscillatingly displacing the oscillating guide member 72 about the oscillating supports 73 and 74 as described above in response to a change in the operating mode of the magnetic recording/reproducing apparatus,
In the embodiment shown in FIGS. 6 and 7, in order to set the position of the inclined surface 72u of the swing guide member 72 at the correct position required according to each operation mode in the magnetic recording and reproducing apparatus, the swing The guide member 72 is driven and displaced by a plunger. Figures 6 and 7
82 is the casing of the main body of the plunger, and 84
83 is an actuating body, 83 is a spring, and 85 and 86 are mounting members for a bracket provided on the aforementioned actuating body 84. The housing 82 of the main body of the plunger has mounting parts 82a, 8
Drum base DB holes 92 and 93 provided in 2b
After aligning with the screw holes 98 and 99 drilled on the side, it is fixed to the drum base DB with screws 96 and 97. Bracket mounting member 85 provided on the operating body 84
, 86 are inserted into the holes 91 of the brackets 87, 88. stick.

When the coil in the casing 82 of the plunger body described above is energized, the actuating body 84 compresses the spring 83 and is attracted into the coil in the casing 82 of the plunger body. As a result, the lower surface of the swing guide member 72 is pressed to the pin 75, but when the lower surface of the swing guide member 72 is pressed to the pin 75 as described above, the swing guide member 72 is tilted. The position of the surface 72u is the same as the reference edge Te of the magnetic tape T where the reference edge Te of the magnetic tape T is to be located when the magnetic recording and reproducing apparatus performs recording and reproducing operations while the magnetic tape T is stopped. When the coil in the casing 82 of the plunger body is cut off, the actuating body 84 moves to the spring 8.
The swinging guide member 72 is pushed up by the elastic force of No. 3, so that the upper surface of the swinging guide member 72 (the bottom surface of the notch 72a in the illustrated embodiment) is pressed against the pin 76. As described above, the position of the inclined surface 72u of the swing guide member 72 is determined by the state in which the top surface of the swing guide member 72 (the bottom surface of the notch 72a in the illustrated embodiment) is crimped onto the pin 76 as described above. A magnetic tape T in which the reference edge Te of the magnetic tape T should be correctly positioned when the magnetic recording and reproducing device performs recording and reproducing operations while the magnetic tape T is running at a running speed in a normal recording and reproducing mode.
The position of the reference edge Te corresponds to the position of the reference edge Te.

The embodiment of the magnetic recording/reproducing apparatus described with reference to FIGS. 6 and 7 is also a magnetic recording/reproducing apparatus equipped with the magnetic tape running system as already described with reference to FIG. In the recording/reproducing operation, the magnetic tape T is wound around the drum at a wrapping angle slightly larger than 180 degrees (approximately 10 degrees), as illustrated in FIG. 16(b). , and the reference surface SF of the reference edge Te of the magnetic tape T at the center of the wrapping angle of the magnetic tape T on the drum (the position indicated by P90 in the figure) {see (d) in FIG. 16} The height H90 from
The position of the reference edge Te is made to be the same as the position of the reference edge Te on the magnetic tape T whose height position is correctly regulated by the guide rollers 5 and 6, which is also shown in 6(a). The inclination angle of the drum, the inclination angles of the inclination guides 3 and 4, etc. are set so that the parts of the magnetic tape T that are in sliding contact with the circumferential surface of the drum do not expand or contract. In the magnetic recording and reproducing apparatus shown in FIGS. 6 and 7, even when the position of the inclined surface 72u of the swing guide member 72 is changed depending on the operation mode, the center of the winding angle of the magnetic tape T with respect to the drum is changed. The height of the corresponding portion from the reference plane SF is H90.

In the embodiment of the magnetic recording and reproducing apparatus described with reference to FIGS. 6 and 7, the swinging guide member 72 is moved to the swinging fulcrum 73,
74 as the center of rotation until its surface comes into contact with the pin 76 or pin 75, and the position of the inclined surface 72u in the swing guide member 72 is adjusted to stop the magnetic tape T. The reference edge T of the magnetic tape T is
The magnetic recording and reproducing apparatus performs recording and reproducing operations in a state in which e matches the position of the reference edge Te of the magnetic tape T to be located and in a state in which the magnetic tape T is running at the running speed in the normal recording and reproducing mode. The reference edge Te of the magnetic tape T should be correctly positioned when performing
The embodiment of the magnetic recording/reproducing apparatus of the present invention shown in FIG. In response to a change in the operation mode of the recording/reproducing apparatus, the swinging guide member 72 is swung around the swinging fulcrums 73 and 74, and its sloped surface 72u is adjusted to perform magnetic recording while the magnetic tape T is stopped. A state in which the reference edge Te of the magnetic tape T matches the position of the reference edge Te of the magnetic tape T to be positioned when the playback device is performing a recording/playback operation, and a state in which the magnetic tape T is placed in the normal recording/playback mode. When the magnetic recording and reproducing device is performing recording and reproducing operations while running at a running speed of In addition to the two positions described above,
Even between two positions, the inclined surface 72 of the swing guide member 72
This is an example of a configuration in which the position of u can be set arbitrarily. In addition, in FIG. 8, only the lower drum Df portion is shown, and illustration of the rotating drum Dr portion is omitted.

In FIG. 8(a), Df is the lower drum, 7
2 has an inclined surface 72u and pivots around pivot points 73 and 74 (however, the pivot point 74, which is 180 degrees symmetrical to the pivot point 73, is not shown in the figure). 100 is a geared motor, 101 is a rotation shaft, 102 is a pinion, 103 is a rack, 104 is a screw for fixing the rack 103 to the swing guide member 72, Further, 125 is a spring attached to the opposite side of the swing guide member 72 from the part to which the rack 103 is fixed, and this spring 125 is biased in a direction to pull the swing guide member 72 toward the fixed part. are doing. An arrow 105 in FIG. 8A indicates a direction in which a portion of the swing guide member 72 to which the rack 103 is fixed is displaced in response to forward and reverse rotation of the geared motor 100 described above. A large number of diagonal lines 72u in FIG. 8(b) indicate that the rack 10 in the swinging guide member 72 corresponds to the forward and reverse rotation of the guard motor 100 in FIG. 8(a).
3 is a diagram illustrating the manner in which the inclined surface 72u of the swing guide member 72 is displaced when the portion to which the numeral 3 is fixed is displaced as indicated by the arrow 105. Therefore, according to the magnetic recording/reproducing apparatus having the configuration shown in FIG.
The magnetic recording and reproducing device performs recording and reproducing operations while the magnetic tape T is running at a normal recording and reproducing mode speed, and the magnetic recording and reproducing device performs recording and reproducing operations while the magnetic tape T is stopped. In addition to the case where slow-motion playback is being performed, it can also be used when slow-motion playback is being performed at any slow-motion ratio. It should be noted that within the range of the state in which the configuration of the running system of the magnetic tape T is not changed, the above-mentioned inclined surface 72u of the swing guide member 72
The present invention may be implemented by changing the inclination angle of the .

In the embodiment of the magnetic recording/reproducing apparatus described with reference to FIGS. 6 to 8, the oscillator, which is loosely fitted on the outer circumferential portion of the lower drum Df, is adapted to change the operating mode of the magnetic recording/reproducing apparatus. The swing guide member 72 is in a state where the swing guide member 72 is oscillated about the swing fulcrums 73 and 74 as the center of swing.
The position of the inclined surface 72u in 2 is switched so that the reference edge Te of the magnetic tape T matches the position of the reference edge Te of the magnetic tape T to be positioned in each operation mode of the magnetic recording and reproducing apparatus. However, in the embodiment of the magnetic recording/reproducing apparatus of the present invention shown in FIG. 9, the inner diameter is smaller than the outer diameter of the lower drum Df (same as the outer diameter of the rotating drum Dr). The swing guide member 107 also has an outer diameter larger than the outer diameter of the lower drum Df.
A small diameter portion 106 is used as the lower drum Df so that the swing guide member 107 can be fitted and attached to the lower drum Df in a freely swingable manner. The edge of the boundary between the small diameter portion 106 and the large diameter portion in the drum Df forms a wall surface perpendicular to the surface of the large diameter portion and the surface of the small diameter portion parallel thereto. In the configuration example shown in FIG. 6, the edges of the boundary between the portion 106 and the large diameter portion have different inclination angles on both sides of the central portion of the winding angle of the magnetic tape T on the drum. It is formed. In addition, in FIG. 9 (the same applies to FIGS. 10 and 11), only the lower drum Df portion is shown, and illustration of the rotating drum Dr portion is omitted. 9(a) shows the lower drum Df in a state where the small diameter portion 106 as described above is formed, and FIG. 9(b) shows the small diameter portion of the lower drum Df where the small diameter portion 106 is formed. A swing guide member 107 that is loosely fitted into a swing guide member 106 and supported swingably, and pins 110, 111 (or screws 110, 111) used as swing fulcrums.
), and FIG. 9(c) shows the small diameter portion 106.
A swinging guide member 107 is loosely fitted into the small diameter portion 106 of the lower drum Df in which the swinging guide member 107 is formed.
The figure shows a state in which it is swingably supported by swing fulcrums 110 and 111.

As described above, the inclination angle of the edge of the boundary between the small diameter part 106 and the large diameter part in the lower drum Df is the part on both sides of the central part of the winding angle of the magnetic tape T on the drum. However, if the magnetic recording/reproducing device is, for example, a VTR based on the VHS (registered trademark) system, and the swinging guide member 107 is configured to swing in response to a change in the operating mode of the magnetic recording/reproducing device, The inclined surface 107 of it is pivoted around the fulcrums 110 and 111.
The position u is the position of the reference edge Te of the magnetic tape T where the reference edge Te of the magnetic tape T is to be located when the magnetic recording and reproducing apparatus is performing recording and reproducing operations with the magnetic tape T stopped. and magnetic tape T.
The reference edge Te of the magnetic tape T at which the reference edge Te of the magnetic tape T should be correctly positioned when the magnetic recording/reproducing apparatus is performing a recording/reproducing operation while the magnetic tape T is running at a running speed in a normal recording/reproducing mode. The angle of inclination of the edge of the boundary between the small diameter portion 106 and the large diameter portion of the lower drum Df in the case where the position is changed to the position corresponding to the position of the magnetic tape T with respect to the drum is 5°56'7. on both sides bordering the center of the wrapping angle.
The angle θo of 4" and the angle θs of 5°58'9.9" are two types of angles that show an extremely small difference in angle, and an edge having such two angles is illustrated. However, it is difficult to visually perceive the angular difference, and it is also not easy to explain the effect of the edges. For this reason, the inclination angle of the edge of the boundary between the small diameter portion 106 and the large diameter portion in the lower drum Df described above is larger than the width on both sides of the central portion of the winding angle of the magnetic tape T on the drum. The embodiment shown in FIG. 9 will be described with reference to FIGS. 11 and 10, which are illustrated assuming two different inclination angles θo and θs.

In FIG. 11, the main structure of the magnetic recording/reproducing apparatus illustrated in FIGS. 11(a) and 11(b) is as follows:
06 is formed in the small diameter portion 10 of the lower drum Df.
The edge of the boundary between 6 and the large diameter part is the entire part of one side (the Fo side part) of the parts on both sides of the center of the wrapping angle of the magnetic tape T on the drum, which is the standard of the drum base. The continuous surface Fo is inclined at an angle θs with respect to the surface, and the other side of the portions on both sides of the center of the winding angle of the magnetic tape T on the drum (Fs side portion) is at an angle θ with respect to the reference plane of the drum base.
In the case where the continuous surface Fs is inclined by an angle o {similar to the configuration of the main part of the magnetic recording and reproducing apparatus illustrated in FIG. 9(c)}, In addition, the main part configuration of the magnetic recording/reproducing device illustrated in FIGS. The edge of the boundary is at an angle θ with respect to the reference plane of the drum base.
The plane Fo is inclined by s, and
A surface where a part of the other side (the Fs side part) of the parts on both sides of the center of the wrapping angle of the magnetic tape T on the drum is inclined by an angle θo with respect to the reference plane of the drum base. This shows a case where the configuration is as shown in Fs. In addition, in the main part configuration of the magnetic recording and reproducing apparatus illustrated in FIGS. A surface Fo formed in a part of one side of both sides of the center of the wrapping angle of the magnetic tape T with respect to the drum at the edge, and a central part of the wrapping angle of the magnetic tape T with respect to the drum. The surface Fs formed on a part of the other side of the border may be formed, for example, so that the length in the edge direction is close to zero.

Referring to FIG. 11, in response to a change in the operating mode of the magnetic recording/reproducing apparatus, the swing guide member 107 moves to swing supports 110 and 111 (however, swing support 111 is not shown in the figure). ), the position of the inclined surface 107u of the swing guide member 107 changes when the magnetic recording and reproducing device performs recording and reproducing operations while the magnetic tape T is stopped. The reference edge Te of the magnetic tape T is to be located at the reference edge Te of the magnetic tape T.
When the magnetic tape T is in the first state corresponding to the position of A second condition is required in which the reference edge Te of the magnetic tape T corresponds to the position of the reference edge Te of the magnetic tape T to be correctly positioned. Then, as shown in FIG. 11, the edge of the boundary between the small diameter portion 106 and the large diameter portion of the lower drum Df is set at the center of the wrapping angle of the magnetic tape T on the drum as described above. At least a part of one side (Fo side part) of the both sides of the drum base is provided with a surface Fo that is inclined by an angle θs with respect to the reference plane of the drum base, and the magnetic tape T is tilted relative to the drum base. A surface Fs is provided in which at least a portion of the other side (Fs side portion) of the portions on both sides bordering the center of the wrapping angle is inclined by an angle θo with respect to the reference plane of the drum base. If the configuration is such that the swing fulcrum 110
, 111 as the center of rotation.
By swinging the swing guide member 107 so that the slope 107u of the swing guide member 107 comes into contact with the above-described surface Fo, the inclination angle of the slope 107u of the swing guide member 107 becomes equal to that of the above-described surface Fo. Since the inclination angle θs is equal to the inclination angle θs, the inclined surface 107u of the swing guide member 107 in this state will cause the slope of the magnetic tape T when the magnetic recording and reproducing apparatus is performing a recording and reproducing operation while the magnetic tape T is stopped. The reference edge Te of the magnetic tape T on which the reference edge Te of the magnetic tape T is to be located
The inclined surface 107u of the swinging guide member 107, which swings around the swinging fulcrums 110 and 111, is brought into contact with the above-mentioned surface Fs. By swinging the swinging guide member 107 so that the swinging guide member 107 is in the
Since the inclination angle of is made equal to the inclination angle θo of the surface Fs described above, the inclination surface 107u of the swing guide member 107 in this state is the state in which the magnetic tape T is running at the running speed in the normal recording and reproducing mode. When the magnetic recording/reproducing apparatus is performing a recording/reproducing operation, a second state is established in which the reference edge Te of the magnetic tape T coincides with the position of the reference edge Te of the magnetic tape T to be positioned. .

FIG. 10(a) is a side view of the lower drum without the small diameter portion 106 as already described with reference to FIGS. A diagonal line Fs in the solid line diagram whose angle is θo indicates that the magnetic tape T is running at a running speed in a normal recording and reproducing mode and the magnetic recording and reproducing apparatus is performing a recording and reproducing operation. The dotted diagonal line Fo indicates the position of the reference edge Te of the magnetic tape T where the reference edge Te of the magnetic tape T is to be located, and the angle formed with the reference surface on the drum base is shown as θs in this figure. indicates the position of the reference edge Te of the magnetic tape T where the reference edge Te of the magnetic tape T should be located when the magnetic recording and reproducing apparatus is performing recording and reproducing operations with the magnetic tape T in a stopped state. In addition, (b) of FIG. 10 shows that the edge of the boundary between the small diameter portion 106 and the large diameter portion of the lower drum Df is located on one side of the portion on both sides of the center of the winding angle of the magnetic tape T on the drum. An angle θ with respect to the reference plane of the drum base at least in part in the part of
In addition to providing a surface Fo that is inclined by an amount s (the oblique line shown by the dotted line in the figure indicates the inclination), a 10 is a diagram showing a side surface shape of the lower drum Df in a state where at least a part thereof is provided with an inclined surface Fs shown by oblique lines in the solid line in the drawing, which is inclined by an angle θo with respect to the reference plane of the drum base, and FIG. (f) of FIG. 10 is (b) of FIG.
) is a bottom view of the lower drum shown in FIG. The edge of the boundary between the small diameter part 106 and the large diameter part of the lower drum Df in the 95 degree range shown by the dotted line in the circumferential direction on one side is inclined by an angle θs with respect to the reference plane of the drum base. The edge of the boundary between the small diameter portion 106 and the large diameter portion of the lower drum Df in the range of 95 degrees in the circumferential direction on the other side from the above-mentioned position P90 as shown by the solid line is the reference point of the drum base. It is shown that the surface Fs is inclined at an angle θo with respect to the surface, and the portion other than the above may be a surface having an arbitrary inclination angle. FIG. 10(c) shows the swinging fulcrums 110, 11
1 (However, the swing fulcrum 111 is not shown in the figure)
FIG. 3 is a side view of the swing guide member 107 that swings with the swing center at . FIGS. 10(d) and 10(e) show states in which the swinging guide member 107 is tilted in different inclination modes when the swinging guide member 107 is swingably attached to the lower drum Df. FIG. 10(d) shows an inclination at an angle θo with respect to the reference plane of the drum base at the edge of the boundary between the small diameter part 106 and the large diameter part in the lower drum Df. Swing guide member 1 on surface Fs
A state in which the swinging guide member 107 is driven to swing by a drive mechanism (not shown) in a state in which the inclined surface 107u of 07 is in contact, that is, the magnetic tape T is run at the running speed in the normal recording/reproducing mode. 10 is a diagram showing a swinging state of the swinging guide member 107 when the magnetic recording and reproducing device is caused to perform a recording and reproducing operation in a state where the magnetic recording and reproducing device is
In addition, (e) in FIG. 10 shows the small diameter portion 1 in the lower drum Df.
The swing guide member 107 is guided so that the slope 107u of the swing guide member 107 is in contact with the slope Fo which is inclined by an angle θs with respect to the reference plane of the drum base at the edge of the boundary between the drum base and the large diameter portion. The swing guide member in a state in which the member 107 is swing-driven by a drive mechanism (not shown), that is, in a state in which the magnetic tape T is stopped and the magnetic recording and playback device is caused to perform a recording and playback operation. 107 is a diagram showing a swinging state of the device. Note that the display of Tp/2 in FIGS. 10(d) and 10(e) indicates that the position of the inclined surface 107u in the swing guide member 107 is changed depending on the change in the operation mode of the magnetic recording/reproducing device. Even in the case where the height from the reference plane of the part P90 corresponding to the central part of the winding angle of the magnetic tape T on the drum is H90, the magnetic tape at both ends of the winding of the magnetic tape T on the drum The position of the reference edge Te of the tape changes to half of one track pitch (
This shows that a positional shift of Tp/2) occurs.

In the embodiment of the magnetic recording and reproducing apparatus of the present invention shown in FIG.
is fitted loosely, and the swing guide member 107 is attached to the swing fulcrum 110 at the position of the hole 112 provided in the small diameter portion 106 of the lower drum DF.
Swing guide member 1 swingably supported by 111
07 is oscillatedly displaced by the operation of the plunger 126, for example. In FIG. 9, 128 is an actuating body of the plunger 126, and 127 is a spring. When the plunger 126 is energized and the actuating rod 128 is displaced downward in the figure, the swing guide member 107 is in the state shown in FIG. 10(e). When the plunger 126 is de-energized, the spring 127 causes the operating rod 128 to move upward in the figure, causing the swing guide member 107 to move as shown in FIG.
It is swung so that it is in the state d). The swing guide member 107 is swing-driven by the operation of the plunger 126, for example. Note that the stopper for determining the position of the swing guide member 107 is the lower drum D as described above.
An inclined surface Fs that is inclined at an angle θo with respect to the reference plane of the drum base at the edge of the boundary between the small diameter section 106 and the large diameter section at f, and a boundary between the small diameter section 106 and the large diameter section at the lower drum Df. Not only is an inclined surface Fo inclined at an angle θs with respect to the reference plane of the drum base on the edge of the drum base, but also an inclination angle defined by the above-mentioned inclined surface Fs and an inclination angle defined by the inclined surface Fo are used. The position of the inclined surface 107u of the swinging guide member 107 is determined by a stopper provided so that the position of the inclined surface 107u of the swinging guide member 107 is set at an arbitrary specific inclination angle between Good too. In addition, the swing guide member 1
The driving source for the swinging displacement of the swinging guide member 107 is not limited to the plunger 126 as shown in FIG. If used, the swing guide member 107
The position of the magnetic tape T when the magnetic recording/reproducing device is performing recording/reproducing operation while the magnetic tape T is running at the running speed in the normal recording/reproducing mode, and the position of the magnetic tape T
In addition to the two positions when the magnetic recording and reproducing device is performing recording and reproducing operations while the magnetic recording and reproducing device is stopped, the position is set to the position when slow motion reproducing operations are performed at an arbitrary slow motion ratio. You can also do it. Note that the inclination angle of the inclined surface 107u of the swing guide member 107 described above corresponds to the state in which the running speed of the magnetic tape T is changed within the range of the state in which the configuration of the running system of the magnetic tape T is not changed. It goes without saying that the present invention may be implemented by changing the .

In the magnetic recording and reproducing apparatus described with reference to FIGS. 9 to 11, the edge of the boundary between the small diameter portion 106 and the large diameter portion of the lower drum Df, on which the small diameter portion 106 is formed, is connected to the magnetic field of the drum. At least a part of one side of both sides of the tape T with the central part of the winding angle as a border is made into a surface that is inclined at an angle θs with respect to the reference plane of the drum base, and the magnetic tape is attached to the drum. A small diameter portion 106 in the lower drum Df in which at least a portion of the other side of the portions on both sides bordering the central portion of the wrapping angle of T is a surface inclined by an angle θo with respect to the reference plane of the drum base. A swing guide member 107 having a surface 107u having a constant inclination angle is swingably attached to the swing guide member 107.
The above-mentioned swing guide member 107 was arranged to swing and displace according to the operating mode of the magnetic recording/reproducing device, but the present invention provides a structure in which the swing guide member 113 is fixedly provided as illustrated in FIG. The drum structure is swingably attached to the swing guide member 113, and the drum structure is swingably displaced relative to the swing guide member 113 in accordance with the operating mode of the magnetic recording/reproducing device. It is okay to do so. In addition, in (a) to (c) of FIG. 12, only the lower drum Df is shown, and the rotating drum Dr is not shown.

Now, in the magnetic recording/reproducing apparatus shown in FIGS. 12(a) to 12(c), the edge of the boundary between the small diameter portion 106 and the large diameter portion of the lower drum Df is as described above. At least a portion of one of the portions on both sides of the central portion of the winding angle of the magnetic tape T on the drum is provided with a surface Fo that is inclined by an angle θs with respect to the reference surface of the drum base. At the same time, there is a surface Fs in which at least a part of the other side of the part on both sides of the center of the wrapping angle of the magnetic tape T on the drum is inclined by an angle θo with respect to the reference plane of the drum base. It is configured in such a manner that it is provided. and,
When a driving force as indicated by the white arrow in the figure is applied to the lower drum Df from a drive source (not shown), the swing fulcrum 1
The lower drum Df swings around the swing guide member 11 with 14 as the swing center.
3. So, for example, (b
) as shown in FIG. As shown in (c), the inclined surface F described above is the inclined surface 113u of the swing guide member 113 described above.
By swinging the lower drum Df by ΔL so that the drum o is brought into contact with the magnet, the magnetic recording and reproducing apparatus illustrated in FIG. It is easy to understand that it is possible to perform recording and reproducing operations similar to those of a recording and reproducing device.

Next, an embodiment of the magnetic recording/reproducing apparatus of the present invention shown in FIG. 13 will be described. 115 in FIG.
is a helical rotation guide member that is used by being fitted onto the outer periphery of the lower drum Df. This spiral rotation guide member 115 has an inclined surface 115u formed on one end surface thereof, and cam grooves 117 and 119 are bored at 180 degree symmetrical positions on the circumferential surface of the spiral rotation guide member 115. ing. The cam grooves 117 and 119 are bored at 180 degree symmetrical positions on the circumferential surface of the spiral rotation guide member 115.
Pins 116 and 118 are inserted at 180-degree symmetrical positions on the outer circumference of the lower drum Df. Therefore, when the rotation guide member 115 is drivenly displaced in the direction of arrow 129 and the direction of arrow 130 by the plunger 121 as shown in FIG. 13(c) showing a plan view, The spiral rotation guide member 115 performs a spiral rotation movement on the outer periphery of the lower drum Df, and the position of the inclined surface 115u in the spiral rotation guide member 115 is shown in FIG. 13(d), which is a partial side sectional view. The position changes between the position of the solid line 115uo shown in the middle and the dotted line 115us. As mentioned above, the pins 116 and 118 inserted into the cam grooves 117 and 119 bored at 180-degree symmetrical positions on the circumferential surface of the helical rotation guide member 115 are connected to the pins 116 and 118 at 180 degrees on the outer circumference of the lower drum Df.
Since it is installed at a 0 degree symmetrical position, the position of the perpendicular bisector perpendicular to the straight line connecting the two pins 116 and 118 corresponds to the center of the wrapping angle of the magnetic tape T around the drum. If the part P90 is formed, the part P90 corresponding to the central part of the wrapping angle of the magnetic tape T described above will be formed.
Inclined surface 115 in spiral rotation guide member 115 in
The height H90 of u from the reference plane is the height H90 of the helical rotation guide member 11.
5 does not change even if it performs a spiral rotation. In the figure 12
2 is an actuating body of the plunger 121, 123 is a spring, and 120 is a connecting member between the actuating body 122 of the plunger 121 and the spiral rotation guide member 115.

As described above, the helical rotation guide member 115 performs a helical rotation movement on the outer periphery of the lower drum Df, and the position of the inclined surface 115u of the helical rotation guide member 115 changes as shown in the partial side sectional view. 13(d), the angle of inclination of the inclined surface 115u of the spiral rotation guide member 115 with respect to the drum base is θo, and the spiral rotation in this state The inclined surface 115u of the guide member 115 is arranged so that the reference edge Te of the magnetic tape T is formed when the magnetic recording and reproducing apparatus performs a recording and reproducing operation while the magnetic tape T is traveling at a running speed in a normal recording and reproducing mode. The position of the helical rotation guide member 115 is aligned with the reference edge Te of the magnetic tape T to be positioned, and the spiral rotation guide member 115 is aligned with the position of the reference edge Te of the magnetic tape T to be positioned.
The position of the inclined surface 115u in the spiral rotation guide member 115 is determined by the dotted line 115u shown in FIG.
When it is in the position o, the spiral rotation guide member 115
The angle of inclination of the inclined surface 115u with respect to the drum base is set to θs, and the helical guide member 11 in this state
The inclined surface 115u of No. 5 is located at the reference edge Te of the magnetic tape T where the reference edge Te of the magnetic tape T is to be positioned when the magnetic recording/reproducing apparatus performs recording/reproducing operation while the magnetic tape T is stopped. It is made to match the position of. Therefore, by causing the above-mentioned spiral rotation guide member 115 to perform a spiral rotation movement in a predetermined direction on the outer periphery of the lower drum Df in accordance with the operating mode of the magnetic recording/reproducing apparatus, the magnetic tape T is normally rotated. The position of the inclined surface 115u of the helical rotation guide member 115 is adjusted depending on the operation of both the state in which the magnetic tape T is running at the running speed in the recording/reproduction mode and the state in which the magnetic tape T is stopped. The reference edge Te of the magnetic tape can be guided by the inclined surface 115u of the helical rotation guide member 115 in a state where it is set at the correct position required in the mode.

In each of the embodiments of the magnetic recording and reproducing apparatus of the present invention described so far, the relative position between the rotation locus of the rotating magnetic head and the reference edge Te of the magnetic tape T is switched and changed depending on the operation mode. By doing so, when the magnetic tape T is running at a predetermined running speed, the extension direction of the recording trace formed on the magnetic tape T by the rotation locus of the rotating magnetic head is made to coincide with the reference edge Te of the magnetic tape T. The inclination angle and the extension direction of the recording trace formed on the magnetic tape T by the rotation locus of the rotating magnetic head with respect to the stopped magnetic tape T are made to be the same as the inclination angle formed with the reference edge Te of the magnetic tape T. However, as mentioned above, the lengths of the recording traces recorded on the magnetic tape T corresponding to the same time will be different as described above.
It is a desirable embodiment to solve the above problem by applying well-known means such as using a time axis conversion device.

[0045]

Effects of the Invention As is clear from the above detailed explanation, the magnetic recording and reproducing apparatus of the present invention operates on a magnetic tape T running at a predetermined speed Vs while slidingly contacting a part of the circumferential surface of a drum. , the magnetic tape T is rotated by a rotating magnetic head Ha (Hb) rotating at a predetermined rotation speed Ns.
If a record trace Tra (Trb) is formed such that the angle θs with respect to the reference edge Te of A drum is used to record a recording trace on a magnetic tape T, which is at an angle θs with the reference edge Te of the magnetic tape T, by a rotating magnetic head Ha (Hb) rotating at a predetermined number of rotations Ns. The reference edge Te of the magnetic tape T is formed on the magnetic tape T in such a manner that the position of the reference edge Te of the magnetic tape T at the center of the winding angle of the magnetic tape T is maintained substantially the same. According to the present invention, the position of the magnetic tape T can be stably switched and changed using the component shaped along the reference edge Te of the magnetic tape T in accordance with the switching and changing of the running speed of the magnetic tape T. It does not require the use of extra actuators or expensive slip rings in its implementation, and its simple configuration satisfactorily solves all the conventional problems mentioned above. For example, a VTR can be easily used as a large capacity memory for a computer, or for example for the production of animation at home.
The range of use of VTRs can be significantly expanded, and the range of applications of VTRs in many technical fields can also be expanded.

[Brief explanation of the drawing]

FIG. 1 is a perspective view of an embodiment of a magnetic recording/reproducing apparatus of the present invention.

FIG. 2 is an exploded perspective view of the magnetic recording/reproducing apparatus of the present invention shown in FIG. 1;

FIG. 3 is a schematic side view used to explain the configuration of essential parts of the magnetic recording and reproducing apparatus of the present invention shown in FIG. 1;

FIG. 4 is a perspective view (a) and a side view (b) of essential parts of an embodiment of the magnetic recording/reproducing apparatus of the present invention.

5 is an exploded perspective view of the magnetic recording and reproducing apparatus of the present invention shown in FIG. 4. FIG.

FIG. 6 is a perspective view (a) and a side view (b) of essential parts of an embodiment of the magnetic recording/reproducing device of the present invention.

7 is an exploded perspective view of the magnetic recording/reproducing device of the present invention shown in FIG. 6. FIG.

FIG. 8 is a perspective view (a) of a part of an embodiment of the magnetic recording/reproducing apparatus of the present invention and an explanatory view (b) of an operation mode of the main part.

FIG. 9 is an exploded perspective view (a) of the magnetic recording and reproducing device of the present invention.
, (b) and a partial perspective view.

10 is a diagram for explaining the operation of the magnetic recording/reproducing apparatus of the present invention shown in FIG. 9. FIG.

11 is a diagram for explaining the operating principle and configuration principle of the magnetic recording/reproducing apparatus of the present invention shown in FIG. 9. FIG.

FIG. 12 is a side view of an embodiment of the magnetic recording/reproducing device of the present invention.

13A and 13B are perspective views (a) and (b) of a part of an embodiment of the magnetic recording/reproducing device of the present invention, a plan view (c), and a side view (b) of the main part.

FIG. 14 is a perspective view of a magnetic tape running system of the magnetic recording and reproducing apparatus.

FIG. 15 is a plan view of a track pattern of a magnetic tape.

FIG. 16 is a perspective view (a) and a plan view (b) of a part of the magnetic tape running system of the magnetic recording and reproducing device, and explanatory diagrams (c) and (d) of changes in the position of the reference surface of the magnetic tape. .

[Explanation of symbols]

DA...Drum structure, DB...Drum base, Dr...Rotating drum, Df...Lower drum, M...Motor, Ha, Hb...Rotating magnetic head, T...Magnetic tape, Te...Reference edge of magnetic head T, P90...Relative to drum Position of the center of the winding angle of the magnetic tape T, SF...Reference plane, Fs...At the edge of the boundary between the small diameter part 106 and the large diameter part in the lower drum Df, inclined by an angle θo with respect to the reference plane of the drum base. The inclined surface in the state Fo...The edge of the boundary between the small diameter part 106 and the large diameter part in the lower drum Df has an angle θs with respect to the reference plane of the drum base.
1... supply reel stand, 2... take-up reel stand, 3, 4... inclined guide (slant pole)
, 5, 6...guide roller, 7...impedance roller,
8...Capstan, 9...Pinch roller, 10...Full width erasing head, 11...Audio head and control head, 3
0... Spur gear, 31... Annular guide member, 31s, 31o...
Guide surface of annular guide member, 34...Rotation drive motor, 3
9s, 39o... Guide surface formed on the outer circumference of the lower drum Df, 72, 107, 113... Rocking guide member, 72u... Slanted surface, 73, 74... Rocking guide member 72 swinging relative to the lower drum Df. Swing fulcrum for movably supporting, 82... Housing of plunger main body, 83... Spring, 84... Operating body, 100... Geared motor, 101... Rotating shaft, 102
...pinion, 103...rack, 125...swing guide member 7
2, a spring attached to the opposite side of the part to which the rack 103 is fixed, 106...lower drum D
Small diameter portion of f, 110, 111... Swing fulcrum of swing guide member 107, 115... Spiral rotation guide member used by fitting to the outer periphery of lower drum Df, 117, 119... Cam groove, 11
6,118...Pin, 115u...Spiral rotation guide member 115
slope of

Claims (5)

[Claims] Claim 1: A magnetic tape running at a predetermined speed Vs while slidingly contacting a part of the circumferential surface of the drum, and a magnetic tape running at a predetermined speed Vs while slidingly contacting a part of the circumferential surface of the drum while stopped. In either case, the position of the reference edge of the magnetic tape at the center of the wrapping angle of the magnetic tape on the drum is maintained substantially the same, and The recording trace formed on the magnetic tape by the rotating magnetic head rotating at the rotational speed Ns is set such that the reference edge of the magnetic tape and the extending direction of the recording trace form an angle of a predetermined angle θs. The peripheral surface of the lower drum includes a guide portion having a predetermined length in the direction in which the reference edge of the magnetic tape extends, so as to be formed on the magnetic tape in response to switching changes in the running speed of the magnetic tape. The position of the reference edge of the magnetic tape that is in sliding contact with the circumferential surface of the drum is changed by means of a magnetic tape guiding means constituted by both the lower drum and a member that is loosely fitted into the drum. Magnetic recording and reproducing device. 2. A magnetic tape running at a predetermined speed Vs while slidingly contacting a part of the circumferential surface of the drum, and a magnetic tape running at a predetermined speed Vs while slidingly contacting a part of the circumferential surface of the drum while stopped. In either case, the position of the reference edge of the magnetic tape at the center of the wrapping angle of the magnetic tape on the drum is maintained substantially the same, and The recording trace formed on the magnetic tape by the rotating magnetic head rotating at the rotational speed Ns is set such that the reference edge of the magnetic tape and the extending direction of the recording trace form an angle of a predetermined angle θs. The position of the reference edge of the magnetic tape is changed in response to the above-described change in the running speed of the magnetic tape so that the position of the reference edge of the magnetic tape is changed so as to be formed on the magnetic tape in response to the change in the running speed of the magnetic tape. In this magnetic recording/reproducing device, one end face of the annular body rotatably fitted to the circumferential surface of the lower drum includes a guide portion for the reference edge of the magnetic tape during running of the magnetic tape. The guide portion of the reference edge of the magnetic tape when the magnetic tape is stopped is configured sequentially in the circumferential direction, and the annular body is rotated in the circumferential direction in response to the switching change of the running speed of the magnetic tape. and means for selectively using a predetermined one of the magnetic tape reference edge guide portions formed on one end surface of the annular body for guiding the magnetic tape reference edge. A magnetic recording and reproducing device. 3. A magnetic tape running at a predetermined speed Vs while slidingly contacting a part of the circumferential surface of the drum, and a magnetic tape running at a predetermined speed Vs slidingly contacting a part of the circumferential surface of the drum while stopped. In either case, the position of the reference edge of the magnetic tape at the center of the wrapping angle of the magnetic tape on the drum is maintained substantially the same, and The recording trace formed on the magnetic tape by the rotating magnetic head rotating at the rotational speed Ns is set such that the reference edge of the magnetic tape and the extending direction of the recording trace form an angle of a predetermined angle θs. The position of the reference edge of the magnetic tape is changed in response to the above-described change in the running speed of the magnetic tape so that the position of the reference edge of the magnetic tape is changed so as to be formed on the magnetic tape in response to the change in the running speed of the magnetic tape. A magnetic recording/reproducing apparatus having the above-described structure includes a guide part for the reference edge of the magnetic tape when the magnetic tape is running and a guide part for the reference edge of the magnetic tape when the magnetic tape is stopped on the circumferential surface of the lower drum. The reference edge of the magnetic tape formed on the lower drum is configured sequentially in the circumferential direction, and the lower drum is rotated in the circumferential direction in response to the switching change of the running speed of the magnetic tape. A magnetic recording/reproducing apparatus comprising means for selectively using a predetermined one of the guide parts for guiding a reference edge of a magnetic tape. 4. A magnetic tape running at a predetermined speed Vs while slidingly contacting a part of the circumferential surface of the drum, and a magnetic tape running at a predetermined speed Vs while slidingly contacting a part of the circumferential surface of the drum while stopped. In either case, the position of the reference edge of the magnetic tape at the center of the wrapping angle of the magnetic tape on the drum is maintained substantially the same, and The recording trace formed on the magnetic tape by the rotating magnetic head rotating at the rotational speed Ns is set such that the reference edge of the magnetic tape and the extending direction of the recording trace form an angle of a predetermined angle θs. The position of the reference edge of the magnetic tape is changed in response to the above-described change in the running speed of the magnetic tape so that the position of the reference edge of the magnetic tape is changed so as to be formed on the magnetic tape in response to the change in the running speed of the magnetic tape. A magnetic recording/reproducing device according to the present invention, wherein the annular body is supported by a swinging fulcrum provided at the center of the winding angle of the magnetic tape around the lower drum and is loosely fitted around the circumferential surface of the lower drum. a first oscillating position in which one end surface thereof is in a oscillating displacement state such that it can be used as a guide for the reference edge of the magnetic tape during running of the magnetic tape, and a stop of the magnetic tape. In response to the change in the running speed of the magnetic tape, the second swing position is set to a swing displacement state that can be used as a guide for the reference edge of the magnetic tape. 1. A magnetic recording and reproducing device comprising means for driving the magnetic recording device to 5. A magnetic tape running at a predetermined speed Vs while slidingly contacting a part of the circumferential surface of the drum, and a magnetic tape running at a predetermined speed Vs slidingly contacting a part of the circumferential surface of the drum while stopped. In either case, the position of the reference edge of the magnetic tape at the center of the wrapping angle of the magnetic tape on the drum is maintained substantially the same, and The recording trace formed on the magnetic tape by the rotating magnetic head rotating at the rotational speed Ns is set such that the reference edge of the magnetic tape and the extending direction of the recording trace form an angle of a predetermined angle θs. The position of the reference edge of the magnetic tape is changed in response to the above-described change in the running speed of the magnetic tape so that the position of the reference edge of the magnetic tape is changed so as to be formed on the magnetic tape in response to the change in the running speed of the magnetic tape. In the magnetic recording and reproducing device, the magnetic tape is wound around the lower drum near the part where the reference edge of the magnetic tape is located in the part of the outer peripheral surface of the lower drum where the magnetic tape is in sliding contact. A first edge shape corresponding to a guide portion of a reference edge of the magnetic tape during running of the magnetic tape is provided on at least a portion of one side of the corner with the center portion as a boundary, and a first edge shape that corresponds to a guide portion of a reference edge of the magnetic tape when the magnetic tape is running is provided on at least a portion of the other side. The lower drum is configured with a small diameter portion in such a manner that a second edge shape corresponding to the guide portion of the reference edge of the magnetic tape is formed when the magnetic tape is stopped; One end surface of the annular body is supported by a swing fulcrum provided at the center of the winding angle of the magnetic tape and is loosely fitted around the outer periphery of the small diameter portion of the lower drum. The position of the end surface of the guide portion of the reference edge of the magnetic tape having the first edge shape in the lower drum and the second edge shape corresponding to the switching change of the running speed of the magnetic tape. A magnetic recording/reproducing device comprising means for driving a reference edge of a magnetic tape to selectively switch to a predetermined position within a range of the position of an end face of a guide portion.