JPH0719324B2 - Rotating head type magnetic recording / reproducing device - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rotary head type magnetic recording / reproducing apparatus such as a video tape recorder, and more specifically, each head chip and rotary of a rotary head in such an apparatus. The present invention relates to an arrangement structure of lead wires that electrically connect to a rotor part of a transformer.

[Conventional technology]

As is well known, a rotary magnetic head device of a video tape recorder (hereinafter referred to as VTR), which is an example of a conventional device of this type, is configured, for example, as shown in FIG.

That is, the rotary magnetic head device 10 includes a first recording / reproducing first head chip 1a and a second recording / reproducing second head chip 1a at diametrically symmetrical positions on the lower surface of a rotating cylinder 1 made of a thick disk such as an aluminum alloy. The head chips 1b are fixed so that the tips of the respective head chips face the outer peripheral edge. The rotary cylinder 1 is integrally attached to the drive shaft 2 by fixing its center portion to a flange 3 which is coaxially press-fitted and fixed to a drive shaft 2 rotated by a drive motor (not shown). On the lower surface of the flange 3, a thin donut-shaped rotor 4a of the rotary transformer 4 is fixed coaxially with the shaft 2 by an adhesive or the like. The rotary transformer 4 electromagnetically converts a recording or reproducing signal and transmits / receives it to / from the head chips 1a, 1b. Two lower concentric grooves are formed on the lower surface of the rotor 4a. And
A thin copper wire is wound a predetermined number of times in each groove to form first and second coils. For example, the first coil wound in the first groove is the first coil. Head chip 1a
And the second coil wound in the second groove is connected to the second head chip 1b.

A rotary bearing 5 made of a ball bearing is press-fitted and fixed slightly above the center of the shaft 2, and a rotation made of a ball bearing having a slightly smaller outer diameter than the ball bearing is provided near the lower end of the shaft 2. The bearing 6 is press-fitted and fixed. And, a fixed torch-shaped fixed cylinder 7 made of aluminum alloy or the like.
Are press-fitted into the two bearings 5 and 6 and are coaxially arranged on the shaft 2. A circular cylinder portion 7b is formed on an upper portion of the fixed cylinder 7 by an outer peripheral wall 7a having a predetermined width, and the bearing 5 is formed at the center of the bottom surface of the cylinder portion 7b.
The outer ring is fixed, and the outer ring of the bearing 6 is fixed in the lower cylinder of the fixed cylinder 7, so that the drive shaft 2 is rotatably supported in the fixed cylinder 7. A thin donut-shaped stator 4b of the rotary transformer 4 is fixed on the bottom surface of the cylinder portion 7b with an adhesive or the like, and is arranged around the shaft 2. The stator 4b and the rotor 4a are arranged so as to face each other so as to maintain a predetermined minute interval, and form a plane-opposed rotary transformer 4. Similar to the rotor 4a, first and second coils are disposed on the upper surface of the stator 4b, and the first and second coils disposed on the stator 4b are respectively disposed on the rotor 4a. It is arranged so as to face the above-mentioned first and second coils, and a signal current to be magnetically recorded and a signal current to be magnetically reproduced flow in this coil.

The fixed cylinder 7 is fixed to the VTR main body (not shown) by appropriate means.

The operation of the rotary magnetic head device 10 configured as described above will be described. As is well known, the video tape loaded in the VTR is inclined and the rotary cylinder 1 is rotated.
Also, since it is wound at an angle of 180 ° + α ° with respect to the fixed cylinder 7 and travels at a high speed, the rotary cylinder 1 rotates in the opposite direction to this tape at the same high speed as the running video tape. The above-mentioned first and second head chips 1a and 1b fixed to each other are adapted to record and reproduce a predetermined information signal while slidingly contacting with each other with a light pressure. At this time, for example, the information signal recorded as a magnetic signal on the video tape, which is detected by the second head chip 1b during reproduction, is the rotary transformer 4.
Is sent to the rotor 4a via a lead wire (not shown), and is magnetically converted by the second coil wound around the second groove of the rotor 4a to generate a magnetic flux. This magnetically converted magnetic flux is induced as a signal current in the second coil by magnetically joining with the second coil wound around the stator 4b, and is processed by an appropriate processing circuit (not shown), Eventually, it is projected as an image on a home television or the like.

By the way, it is conceivable to reduce the size of the rotary magnetic head as part of the miniaturization of the VTR. In this case, in order to make it compatible with conventional video tapes, as shown in FIG.
1, the second head chip 11a, 11b and the first for the left azimuth
It is necessary to skillfully support the azimuth recording method by using the third and fourth head chips 12a and 12b. That is, as described above, in order to maintain compatibility, a total of four head chips must be used, and naturally four coils corresponding to each head chip must be provided in the rotary transformer. .

An example of this is shown in FIG.
The rotor 13 and the stator 14 of 15 are arranged so as to face each other at a predetermined minute interval, and four grooves are concentrically formed on the lower surface of the rotor 13 and the coil is provided in each groove.
13a, 13b, 13c, 13d are wound a predetermined number of times. Further, on the upper surface of the stator 14, first, second, third, and fourth coils 14a, 14b, 14c, 14d are arranged in the same manner as the coils 13a to 13d, and each of them is arranged on the rotor 13 1st, 2nd, 3rd,
The fourth coils 13a, 13b, 13c and 13d are arranged to face each other.

And a VTR using four head chips like this
Returning to the explanation of the circuit configuration (refer to FIG. 2) of the main part of the (hereinafter referred to as 4-head VTR), the signal input terminal 26 for recording on a video tape is the input end of the FM modulators 24a, 24b. The output terminals of the modulators 24a and 24b are connected to the input terminals of the current amplifiers 22a and 22b, respectively. The amplifiers 22a and 22b are switchers 21a and 22a for alternately switching to left azimuth or right azimuth, respectively.
It is connected to 21b. A first output end of the switcher 21a is a first coil 14a arranged on the stator 14.
Is connected to the first input terminal of the switcher 21c described below. The second output terminal of the switcher 21a is connected to the second coil 14b and the second input terminal of the switcher 21c. Further, the first coil 13a of the rotor 13 facing the first coil 14a is connected to one end of the coil wound around the first head chip 11a for the right azimuth. The other end of the coil is connected to ground. Similarly, the second coil 13b is connected to one end of a coil wound around the third head chip 12a for the left azimuth, and the other end of the coil is connected to the ground.

The first output terminal of the switcher 21b is connected to the third coil 14c and the first input terminal of the switcher 21d as described above, and the second output terminal of the switcher 21b is connected to the fourth coil 14d.
And the second input terminal of the switcher 21d. The third coil 13c facing the third coil 14c is connected to one end of a coil wound around the second head chip 11b for the right azimuth, and the other end of the coil is connected to the ground. Has been done. In addition, the fourth coil 14d
The fourth coil 13d facing to is the fourth coil for the left azimuth.
Is connected to one end of a coil wound around the head chip 12b, and the other end of the coil is connected to the ground.

Similarly, the first to fourth head chips 11a, 11b, 12a, 12
The output terminal 27 of the reproduced signal sent from b is the FM demodulators 25a, 2
5b is connected to each output terminal of the demodulator 25a,
The input ends of 25b are connected to the output ends of the voltage amplifiers 23a and 23b, respectively. The respective input ends of the voltage amplifiers 23a and 23b are connected to the respective output ends of switchers 21c and 21d for switching to the left and right azimuths as described above.

The operation of recording / reproducing compatible with the conventional video tape by using the 4-head VTR thus constructed will be described.
The signal current supplied from 26 is FM-modulated by the FM modulators 24a, 24b, current-amplified by the current amplifiers 22a, 22b, respectively, and further switched by the switchers 21a, 21b for a predetermined time, while the first, second Coils 14a, 14b and
It is supplied to the third and fourth coils 14c and 14d. Then, the coils 14a, 14b, 14c, 14d and the coils 13a, 13b, 13c, 13d are electromagnetically coupled, and the head chips 11a, 12a, 11b, 12b.
Magnetically recorded on video tape by.

However, if a 4-head VTR is configured in this way,
As shown in FIG. 3 above, since the distance between the coils 13a, 13b, 13c and 13d provided on the rotor 13 becomes very small, crosstalk of the signal current occurs, and the stator 14 is further provided with the crosstalk. Crosstalk similarly occurs in the coils 14a, 14b, 14c, 14d thus formed, so that the signal current cannot be transmitted / received accurately.

Therefore, as a means for preventing the crosstalk, as shown in FIG. 3, U is so set as to cover the coils 13a, 13b, 13c, 13d and 14a, 14b, 14c, 14d of the rotor 13 and the stator 14, respectively. It is conceivable to use a shield material 13e, 13f, 13g, 13h and 14e, 14f, 14g, 14h having a character shape for shielding.

When shielded in this way, the crosstalk is
It can be prevented. On the other hand, the rotary cylinder and the rotor portion of the rotary transformer are coupled by a shaft and integrated, and a plurality of (for example, 4
Head chips are fixed respectively. Each head chip and the rotor portion of the rotary transformer are electrically connected by a lead wire to exchange information signals. These heads (hence, the rotary cylinders) and the rotor portion are connected by a shaft (shaft) so that they rotate integrally without any relative displacement. Therefore, in order to electrically connect each of the head chips to the rotor portion of the rotary transformer by a lead wire, the shaft is made hollow and the hollow portion is used as a lead wire insertion path. . However, if the lead wire led out from each head chip is directly inserted into the hollow part of the shaft and directly connected to the tap or terminal of the rotor part of the rotary transformer, it takes time and effort for the connection work, resulting in extremely low productivity. Resulting in. Further, workability such as replacement of the head chip at the time of later repair becomes very poor.

[Problems to be Solved by the Invention]

The present invention was made in view of the above circumstances,
It is an object of the present invention to provide a device of this type that is easy to manufacture and repair and is practical.

[Means and Actions for Solving Problems]

In order to solve the above problems, a rotary head type magnetic recording / reproducing apparatus of the present invention includes: a rotary head cylinder for relatively moving a tape-shaped magnetic recording medium along a predetermined portion of its peripheral surface; A rotary magnetic head whose movement locus is substantially along the peripheral surface of the rotary head cylinder, and which records or reproduces an information signal while slidingly contacting the tape-shaped magnetic recording medium; and the rotary head cylinder. And a rotary transformer for relaying transfer of the information signal to and from the rotary magnetic head, the rotary head having a rotor coupled to the rotary part of the rotor by a shaft so as to rotate integrally. In the magnetic recording / reproducing apparatus, the shaft is formed as a hollow shaft having a predetermined hollow portion inside thereof, and this hollow portion is connected to the rotary magnetic head and the rotary magnetic head. A relay wire is provided as an insertion path for a lead wire for electrically connecting the tally transformer, and for electrically connecting the rotary magnetic head and the rotary transformer, a relay disposed in the rotary head cylinder. Board (35)
The relay board is an annular one that is concentrically fitted to the rotary head cylinder in the board mounting recess (31b) above the rotary head cylinder. A plurality of cut-out holes (35b to 35e) for inserting the corresponding lead wires are formed on the inner peripheral edge of the ring-shaped relay board at predetermined intervals in the circumferential direction from the central space to the outside. A tool is inserted from above the relay board (35) when adjusting the relative position of each corresponding head with respect to the rotary head cylinder, which is formed in a radial pattern and is adjacent to each other in the middle portion of each of the cut holes. The small holes (35f to 35i) for permitting the above are respectively formed, and the above-mentioned corresponding to each part between the adjacent cut holes (35b to 35e) and the small holes (35f to 35i). Conductor patterns (35a, 35a) for connecting and connecting lead wires by soldering Wherein the vignetting composed.

〔Example〕

Hereinafter, the present invention will be clarified by describing in detail one embodiment shown in the drawings. As shown in FIG. 4, the rotary magnetic head device 100 comprises a rotary cylinder portion 30 and a fixed cylinder portion 50.

The rotary cylinder portion 30 is composed of a rotary cylinder 31, a drive shaft 32, a flange 34, a pulley 37 and the like.
The drive shaft 32 is composed of a hollow shaft, and a slightly thick disk-shaped flange 34 is provided on the upper side thereof.
It is press-fitted and fixed to 32 and integrally attached, and a thick disk-shaped rotary cylinder 31 made of an aluminum alloy or the like is received so as to come into contact with the upper surface of the flange 34.
Is fixed to the shaft 32. A circular cutting hole 31a centered on the shaft 32 is formed at the center of the lower surface of the cylinder 31 at a depth substantially equal to the thickness of the flange 34, and a diameter slightly larger than the diameter of the flange 34,
There is a positional relationship in which the flange 34 enters the cutting hole 31a. Further, on the upper surface of the rotary cylinder 31, there is formed a circular cutting hole 31b centered on the shaft 32 and having a diameter slightly larger than the diameter of a relay substrate 35 (see FIG. 6) described below and having a predetermined depth. It is provided. A male screw portion is engraved on the upper end portion of the shaft 32, and a slightly larger tightening nut 33 is screwed into the male screw portion, and the rotary cylinder is formed by the flange 34 and the tightening nut 33.
It is designed to secure 31 to drive shaft 32 firmly. In the cutting hole 31b of the cylinder 31, the relay board 35 made of a printed board or the like is fixed by an appropriate means as shown in FIG. This relay board 35 has a donut shape and is formed from the cutting hole 31b of the rotary cylinder 31.
The outer diameter is slightly smaller and the inner diameter is larger than the maximum diameter of the tightening nut 33. And the same board
There are four radial cut holes 35b, 35c, 35d, 35e whose inner diameter is 90 ° from the center of 35, and a bundle line 39 to be described later is formed in these cut holes 35b to 35e. The individual lead wires branched from are inserted. Further, head chips 36a and 36 to be described later are provided at two intermediate positions of the cut holes 35b to 35e which are adjacent to each other at positions which form an angle of 90 ° from the center of the substrate 35.
Small holes 35f, 35g, 35h, 35i are formed to insert a driver for adjusting the heights of b, 36c, 36d. Furthermore,
Conductor patterns 35a and 35a are provided between the cut holes 35b to 35e and the small holes 35f to 35i on the upper surface of the substrate 35, and the conductor patterns 35a and 35a are provided on the conductor pattern and the end lead wires of the bundled wire 39. Each of the lead wire ends of the head shown by the broken line is soldered to connect and connect the two.

As shown in FIG. 5, on the lower surface of the rotary cylinder 31, four head chips 36a, 36 are located on the diagonal lines forming 90 ° with each other and near the outer peripheral edge of the cylinder 31.
The same head chip 3 for disposing b, 36c, 36d respectively
4 head support plates 36e, 36f, 36 fixing 6a to 36d
g and 36h are fixed with screws. Also, four screws 42a, 42b, for adjusting the height of the head chips 36a to 36d are provided at the centers of the head support plates 36e to 36h, respectively.
42c, 42d are arranged, these screws 42a ~ 42d,
The four small holes 35f to 35i provided on the relay board 35 described above.
Insert the screwdriver from the
The height of a to 36d can be adjusted. That is, the four small holes 35f to 35i provided on the relay board 35 and the adjusting screws 42a to 42d are in a positional relationship corresponding to each other. As in conventional devices of this type, each head chip
The rotation track of the medium sliding contact surfaces of 36a to 36d is the rotation cylinder 31.
It is located along the circumference of.

Furthermore, as shown in FIG. 5, the rotary cylinder 31 is located at a position corresponding to each of the cut holes 35b to 35e provided on the relay board 35 on a diagonal line of an angle of 90 ° from the center thereof. Four through holes 31c, 31d, 31e, 31f for inserting the branch lead wires of the bundle 39 are formed.

On the other hand, at the lower end of the shaft 32, a circular pulley 37 is press-fitted and integrally attached to the shaft 32 as shown in FIG. The pulley 37 is formed of a thick disc having a diameter larger than the diameter of the rotary cylinder 31, and the upper surface of the pulley 37 has the above-mentioned rotary cylinder.
A relatively deep circular recess 37 having a diameter slightly larger than the diameter of 31 is formed. A thin donut-shaped rotor 38 of the rotary transformer is fixed in the recess 37a with an adhesive or the like. This rotor 38 is already the third
It has the same configuration as the rotor 13 shown in the figure, in which four shielded coils are concentrically arranged, and a bundle of lead wires drawn from each coil is bundled. The wire 39 is inserted through the hollow portion of the shaft 32 and connected to the pattern conductors 35a corresponding to the respective lead wires of the relay board 35.
Holes 31f, 31c, 31d, 3 formed in the rotary cylinder 31 from 5
The head chips 36a, 36b, 36c, 36d are appropriately connected through the 1e. A pulley drive belt 41 is wound around the outer peripheral surface of the pulley 37 to transmit the rotational force of a drive motor (not shown).

Immediately below the flange 34, a first rotary bearing 61 is press-fitted and fixed to the shaft 32 at a predetermined interval. Below the bearing 61, a fixed cylinder described below is provided.
A second rotary bearing 62 is press-fitted and fixed at a position separated by substantially the same length as the height of 51.

The fixed cylinder portion 50 includes the fixed cylinder 51, the stator 52 of the rotary transformer, and various members (not shown). The fixed cylinder 51 is composed of an inner cylinder 51a made of aluminum alloy or the like and an outer cylinder 51b having the same diameter as the rotary cylinder 31, and a VTR body (not shown) is provided on the outer periphery of the lower end of the outer cylinder 51b. A flange 51c to be attached is formed. The drive shaft 32 is rotatably inserted into the fixed cylinder 51 by fixing the first and second bearings 61 and 62 to the upper and lower portions of the inner surface of the inner cylinder 51a. Further, the upper end surface of the outer cylinder 51b is chamfered so that the inner side is lowered. In addition, a video tape guide step portion 51d is formed on the outer peripheral surface of the outer cylinder 51b for winding the video tape around the rotating cylinder portion 30 and the fixed cylinder portion 50 and running the same. Is capable of sliding contact while maintaining a predetermined inclination angle.

The stator 52 of the rotary transformer is fixed to the lower surface of the bottom wall of the fixed cylinder 51 so as to face the rotor 38 with an adhesive or the like. The stator 52 has four shielded coils arranged concentrically as already described in FIG.
The four coils of the rotor 38 are paired with each other. Lead wires (not shown) are drawn out from these four coils and are connected to an appropriate signal processing circuit of the VTR main body.

In the rotary magnetic head device 100 configured in this manner, when the drive motor (not shown) rotates, the rotary cylinder section 30 also rotates, and the rotary magnetic head device 100 is wound around and runs, from a video tape (not shown),
For example, when extracting a reproduction signal, the head chip
36a, 36b, 36c, 36d detect magnetic signals corresponding to predetermined azimuths, and the magnetic signals are sent to the corresponding coils on the rotor 38 by the bundled wires 39 via the relay board 35. This coil has 4
Since the individual coils are electromagnetically coupled to each other, the head side and the coil side provided on the stator 52 are connected via such signal coupling (transformer coupling), and are provided on the VTR main body by a lead wire (not shown). The signal is processed by an appropriate reproducing circuit, and finally sent out of the VTR as a standard format composite video signal.

It should be noted that the above description has been given in detail with reference to a VTR as an example of this type of device, but it goes without saying that the present invention can be applied to devices that handle audio signals and other data. Further, in the present embodiment, the head chip is fixed to the rotary cylinder, and only the rotary magnetic head of the type in which the head chip also rotates with the rotation of the rotary cylinder has been described, but the cylinder for guiding the tape is the fixed cylinder. It is needless to say that the present invention can be applied to a rotary magnetic head device of a type in which the head chips are attached to both ends of the head bar and the head bar rotates with respect to the fixed cylinder. Is.

〔The invention's effect〕

According to the present invention, it is possible to realize a device of this type that is easy to manufacture and repair and is practical.

[Brief description of drawings]

FIG. 1 is a sectional view of a main part of a conventional rotary magnetic head, FIG. 2 is a block diagram showing an outline of an electric circuit of a conventional 4-head video tape recorder, and FIG. 3 is shown in FIG. An enlarged cross-sectional view of a main part of a rotary transformer of a 4-head video tape recorder, FIG. 4 is a cross-sectional view of a rotary magnetic head in a video tape recorder showing an embodiment of the present invention, and FIG. 5 is shown in FIG. FIG. 6 is a bottom view of the rotary cylinder of the rotary magnetic head taken along the line VV, and FIG. 6 is a plan view of the relay substrate of the rotary magnetic head shown in FIG. 1,31 …… Rotating cylinder 1a, 1b, 36a, 36b, 36c, 36d …… Head tip 2,32 …… Shaft 3,34 …… Flange 4a, 13,38 …… Rotor 4b, 14,52 …… Stator 7,51 ...... Fixed cylinder 37 ...... Pulley 39 ...... Connection 100 ...... Rotary magnetic head device 35 ...... Relay board

Claims (1)

[Claims] 1. A rotary head cylinder for relatively moving a tape-shaped magnetic recording medium along a predetermined portion of its peripheral surface, and a movement locus of its own medium sliding contact surface is substantially on the rotary head cylinder peripheral surface. A rotary magnetic head that is arranged along the tape-shaped magnetic recording medium and that records or reproduces an information signal while slidingly contacting the tape-shaped magnetic recording medium, and is connected integrally with the rotating portion of the rotating head cylinder by a shaft so as to rotate integrally. In a rotary head type magnetic recording / reproducing apparatus, which comprises a rotary rotor for relaying transmission / reception of the information signal to / from the rotary magnetic head, the shaft has a predetermined internal portion thereof. It is formed as a hollow shaft having a hollow portion, and the hollow portion inserts a lead wire for electrically connecting the rotary magnetic head and the rotary transformer. A relay board (35) arranged in the rotary head cylinder for electrically connecting the rotary magnetic head and the rotary transformer.
The relay board is an annular one that is concentrically fitted to the rotary head cylinder in the board mounting recess (31b) above the rotary head cylinder. A plurality of cut-out holes (35b to 35e) for inserting the corresponding lead wires are formed on the inner peripheral edge of the ring-shaped relay board at predetermined intervals in the circumferential direction from the central space to the outside. A tool is inserted from above the relay board (35) when adjusting the relative position of each corresponding head with respect to the rotary head cylinder, which is formed in a radial pattern and is adjacent to each other in the middle portion of each of the cut holes. The small holes (35f to 35i) for permitting the above are respectively formed, and the above-mentioned corresponding to each part between the adjacent cut holes (35b to 35e) and the small holes (35f to 35i). Conductor patterns (35a, 35a) for connecting and connecting lead wires by soldering Rotary head, characterized in that vignetting comprising magnetic recording and reproducing apparatus.