JPH0458097B2 - - Google Patents

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention automatically reverses both sides A and B of a magnetic tape, and ensures that the next operation is always started from a fixed side, for example, the A side. This invention relates to an auto-reverse device for a tape recorder.

[Conventional technology]

Conventional auto-reverse devices for tape recorders have either electrically detected the end of the tape and operated a solenoid to switch the left and right pinch rollers, or mechanically detected the tension at the end of the tape and There are devices in which the pinch rollers are switched using the rotational force of a wheel or the like.

Further, although there are various types of auto-reverse devices, in all conventional devices, the running direction of the tape at the start of operation is the same as the running direction at the end of the previous operation.

[Problem that the invention seeks to solve]

An auto-reverse device that electrically detects the end of a tape to perform a tape reversing operation has a solenoid, which results in a complicated structure and is disadvantageous in terms of miniaturization.

Auto-reverse devices that use the rotational force of the flywheel to perform tape reversal operations generally have a pin placed on a part of the flywheel.
This pin is configured to lock the pinch roller switching mechanism, which may disturb the balance of the flywheel, and at the time of startup, the tape tension temporarily increases, which may be detected and cause a malfunction.

For example, if there is an order in the recorded contents on both sides A and B of the tape, it is desirable to always start the playback operation from side A, but with all conventional tapes, the running direction of the tape at the start of operation is different from that of the previous one. Since the running direction was the same as the direction at the end of the operation, for example, if the previous operation ended while playing the B side, it was troublesome to have to perform an operation to return to the A side.

[Purpose of the invention]

The present invention has been made to solve these problems, and its purpose is to be able to automatically reverse the tape without using attached parts such as solenoids, and thus to facilitate miniaturization. To provide an auto-reversing device for a tape recorder, which does not have the risk of disturbing the balance of a flywheel or causing malfunction, and further ensures that the running direction of the tape is always constant at the start of operations such as playback and recording.

[Means for solving problems]

The auto-reverse device for a tape recorder according to the present invention includes a rotation transmitting body and a cam follower symmetrically, the rotation transmitting body is provided with an eccentric circular cam surface and a pressing protrusion, and the reel shaft is provided with a pressing urging portion. Provided,
The rotation of the capstan shaft is transmitted to the reel shaft via a rotation transmitting body and further via a friction mechanism. While the reel shaft is rotating, the pressing biasing section biases the cam follower to cause the contact section provided on a part of the cam follower to slide into contact with the cam surface, but when the reel shaft is stopped, When the biasing force of the pressing biasing part disappears and the abutting part comes to stay at a position away from the cam surface, the pressing protrusion hits the abutting part and the rotation transmitting body moves to a non-engaging position with respect to the reel shaft. Move to.
Further, a pinch roller switching member for switching the left and right pinch rollers toward and away from the corresponding capstan shaft is always biased in one direction. The pinch roller switching member moves in the opposite biasing direction in response to the movement of one rotation transmitting body when it disengages from the reel shaft, and is locked by the hook member. This locking is released when the other rotation transmitting body disengages from the reel shaft, and the pinch roller switching member returns to its original position, thereby switching the running direction of the tape. Furthermore, the hook member is released by an interlocking member for determining the operation start surface that operates in conjunction with the stop operation, playback, or recording start operation of the tape recorder, so that the tape running direction at the next start is always constant. I'm trying to follow the direction.

In other words, if the contact part of the cam follower continues to be separated from the cam surface, the pressing protrusion will hit the contact part,
The rotation transmitting body moves and the pinch roller switching member operates, and when the tape recorder stops or during playback or recording operation, the interlocking member for determining the operation start surface operates and starts the next playback or recording. The running direction of the tape during operation is always a constant direction.

With this configuration, the pinch roller switching member does not operate as long as the reel shaft is rotating, and when the reel shaft stops, the switching member shifts and switches between the left and right pinch rollers, so it works like a solenoid. No additional accessories are required, making it easier to downsize.

Furthermore, there is no risk of disturbing the rotational balance of the flywheel or causing malfunctions during startup or the like.

Furthermore, since the running direction of the tape at the start of playback or recording is constant, for example, even if the recorded contents on both sides A and B of the tape are in an order,
There is no need for the trouble of reversing the running direction of the tape when starting the playback operation.

〔Example〕

The figure shows an embodiment of the present invention, and FIG. 1 shows a state where the right reel shaft 1a is rotating.
FIG. 4 shows a state in which the left reel shaft 1b is rotating. Further, FIGS. 2 and 3 show the process in the middle of changing from the state shown in FIG. 1 to the state shown in FIG. 4.

First, if we pay attention to FIG. 1, on both sides of the magnetic head 2 there are capstan shafts 3a, 3b and pinch rollers
a, 4b and the reel shafts 1a, 1b are arranged symmetrically. capstan shaft 3a,
Small gears 5a, 5b and flywheels 6a, 6b are attached to each of the shafts 3b, and rotary plates 7a, 7b which are rotatable about rotation transmitting bodies, that is, respective capstan shafts 3a, 3b are provided. At one end of each rotating plate 7a, 7b, a rotation transmitting body consisting of large and small gears 8a, 8b; 9a, 9b is supported via shafts 10a, 10b, and an eccentric circle shaped cam surface 1
1a, 11b are formed, and furthermore, a pressing protrusion 1 is formed at the maximum radius within each eccentric circular cam surface 11a, 11b.
2a and 12b are continuously provided to protrude from the shafts 10a and 10b. Further, the other end of each rotating plate 7a, 7b is a bent piece 13a, 13b.

The pinch rollers 4a, 4b have shafts 14a, 1
It is supported by supports 15a and 15b which are rotatable about 4b, and can move toward and away from the capstan shaft 3a. Further, each of the supports 15a, 15b is also provided with bent pieces 16a, 16b.

In the figure, reference numeral 17 indicates a pinch roller switching member, that is, a switching plate that can freely slide in the left and right direction.
7 is provided with protrusions 18a and 19 so as to sandwich the bent piece 13a of the right rotating plate 7a, and a protrusion 1 is provided on the left side of the bent piece 3b of the left rotating plate 7b.
8b is provided. Furthermore, each of the supports 15
Openings 20a and 20b into which bent pieces 16a and 16b of a and 15b are inserted are provided, and each opening 2
There are inclined lines 21a, 21b in some parts of 0a, 20b.
is provided. Therefore, when the switching plate 17 moves to the right, the left inclined edge 21b as shown in FIG.
is slid onto the bent piece 16b of the left support 15b, and the left pinch roller 4b is attached to the capstan shaft 3.
When the switching plate 17 moves to the left, the right inclined edge 21a is slid onto the bent piece 16a of the right support 15a, and the right pinch roller 4a is moved. Pull it away from the capstan shaft 3a. However, each of the supports 15a and 15b is biased by a spring (not shown) in a direction that brings each pinch roller 4a and 4b into pressure contact with the capstan shafts 3a and 3b.

Further, a part of the switching plate 17 has an engaging pin 22.
is installed protrudingly. This switching plate 17 is always urged rightward by a tension spring 23.

A hook member 24 is located near the switching plate 17.
is rotatably provided. This hook member has an engaging portion 24a corresponding to the engaging pin 22 and a pressure receiving portion 24b corresponding to the bent piece 13b of the left rotating plate 7b, and is moved counterclockwise in the figure by a tension spring 25. It is rotationally biased.

A large and small integrated gear 8 constituting the rotation transmitting body
a, 8b; Among 9a, 9b, the larger diameter gear 8a,
8b meshes with small gears 5a, 5b which are integrated with the capstan shafts 3a, 3b, and small diameter gears 9a, 9.
b is configured to selectively mesh with large gears 26a and 26b provided coaxially with the reel shafts 1a and 1b. Note that these gears 9a, 26
The meshing of a or the meshing of the gears 9b and 26b is controlled by the rotation of the rotary plates 7a and 7b.
Both rotary plates 7a, 7b have tension springs 2 in the direction of meshing the gears 9a, 9b with the gears 26a, 26b.
7a and 27b. however,
The rotation of the rotation plates 7a and 7b is controlled by the left and right movement of the switching plate 17, and when one gear (for example, the right gear 9a) is meshing with the gear 26a, the other gear 9b is in mesh with the gear 26a. 26b.

The reel shafts 1a, 1b and the large gear 26a,
A friction mechanism (not shown) is inserted between the reel shaft 1 and the reel shaft 26b.
Even if the rotation of the gear 26a is stopped, the large gear 26a can still be rotated by the sliding of the friction mechanism. Rotation detection mechanisms are provided near the reel shafts 1a and 1b, respectively, and receive rotational force only when the reel shafts 1a and 1b are rotating. These rotation detection mechanisms are widely used and well-known ones (for example, disclosed in Japanese Patent Application Laid-open No. 54-39608, etc.), and include rotating members 28a and 28b that receive rotational force only when the reel shafts 1a and 1b are rotating. , pin-shaped pressing urging portions 29a, 29b fixed to these rotating members 28a, 28b.

In the figure, 30 is a fixed plate, and this fixed plate 30 includes cam followers 31a, 31b and a presser auxiliary member 32.
a and 32b are rotatably supported.

The cam followers 31a, 31b have abutting portions 33a, 33b at the farthest portions from the fulcrum position, and have pressure receiving portions 34a, 34b located on the rotational orbits of the pressing biasing portions 29a, 29b, and elastic portions near the fulcrum position. It has pieces 35a and 35b.

Further, the presser auxiliary member 32a is approximately L-shaped, with one side 36a, 36b located outside the shafts 10a, 10b, and the other side 37a, 37b connected to the elastic pieces 35a, 35 of the cam followers 31a, 31b.
It is facing b.

In the figure, reference numeral 38 denotes a stop operation member that intersects with the switching plate 17 and is movable back and forth in the front and rear directions as an interlocking member for determining the operation start plane. This stop operation member 38 has a bulging protrusion 39 on a part of the upper surface,
It is constantly urged in the backward direction by a tension spring 40. When the stop operation member 38 moves forward or backward, the protrusion 39 slides on the lower surface of the rotating end of the hook member 24, as shown in FIG. 5, and the hook member 24 floats upward. At this time, the engaging pin 2 of the switching plate 17 is connected to the engaging portion 24a of the hook member 24.
2 is engaged, the hook member 24 floats up to release the engagement.

Next, the effect will be explained.

In FIG. 1, the magnetic head 2 is held in the operating position, the right pinch roller 4a is pressed against the capstan shaft 3a, and the rotation of the capstan shaft 3a in the direction of the arrow is caused by the gears 5a, 8a, 9a, 26a and the right pinch roller 4a. A state in which the reproduction operation is performed by being transmitted to the right reel shaft 1a via a friction mechanism (not shown) is shown (however, the magnetic tape is omitted in the drawing).

At this time, the rotational force of the reel shaft 1a is applied to the rotating member 2.
8a, and press biasing portion 2 of rotating member 28a.
9a presses the pressure receiving part 34a of the cam follower 31a, so the contact part 33a of the cam follower 31a comes into sliding contact with the cam surface 11a. In this way, the contact portion 33
As long as a is in sliding contact with the cam surface 11a, the contact portion 3
3a and the pressing protrusion 12a never come into contact with each other.

When the tape is being played back while being wound around the right reel shaft 1a in this way,
Since the left reel shaft 1b is on the feeding side, the pressing force section 29b is connected to the pressure receiving section 34 of the cam follower 31b.
Do not press b. However, in this state, the left rotation transmitting body (gears 8b, 9b) has moved away from the large gear 26b and has moved to a non-engaging position with respect to the reel shaft 1b, and the shaft 10b presses one side 36b of the presser auxiliary member 32b. are doing. For this reason, presser foot auxiliary member 3
The other side 37b of the cam follower 31b comes to press the elastic piece 35b of the cam follower 31b, and the presser auxiliary member 32b instead of the pressing biasing part 29b holds the contact part 33b of the cam follower 31 in sliding contact with the cam surface 11b. become.

Next, when the tape is completely wound onto the right reel, a slip occurs in the friction mechanism inserted between the large gear 26a and the reel shaft 1a.
The reel shaft 1a stops. Due to this stop, the pressure urging portion 29a is activated by the pressure receiving portion 3 of the cam follower 31a.
4a is no longer pressed, the contact part 33a that is in sliding contact with the cam surface 11a separates from the cam surface 11a at the point closest to the shaft 10a, so that the pressing protrusion 12a comes into contact with the contact part 33a as shown in FIG. become. In this case, the fulcrum of the cam follower 31a does not move, so the rotation transmitting body, that is, the rotating plate 7
A rotates against the spring 27a and separates the gear 9a from the large gear 26a. As a result, the transmission of rotational force to the large gear 26a is cut off.

On the other hand, due to the rotation of the rotating plate 7a, this rotating plate 7
The bent piece 13a presses the protrusion 19 of the switching plate 17 from the right side as shown in FIG. 3, and moves the switching plate 17 to the left. As a result, the engagement pin 22 provided on the switching plate 17 is connected to the engagement portion 24 of the hook member 24.
(Fig. 4).

At this time, the left inclined edge 21b of the switching plate 17 is released from the support 15b as shown in FIG.
a is rotated in the opposite direction, the left pinch roller 4b comes into pressure contact with the capstan shaft 3b, and the right pinch roller 4a is separated from the capstan shaft 3a.

Further, the left rotating plate 7b is pulled by the spring 27b and rotates clockwise, thereby causing the small gear 9b of the rotation transmitting body to mesh with the large gear 26b.

Therefore, as shown in FIG. 4, the shape is opposite to that in FIG. 1, and the left reel shaft 1b rotates in the winding direction and the tape is wound on the left reel while playback or recording is performed. You will be able to do it.

When the tape is completely wound onto the left reel in this manner, a friction mechanism inserted between the large gear 26b and the reel shaft 1b slips, and the reel shaft 1b stops. Due to this stop, the pressure urging portion 29b no longer presses the pressure receiving portion 34b of the cam follower 31b, so the cam surface 11b
The contact portion 33b that is in sliding contact with the shaft 10b comes closest to the shaft 10b and then separates from the cam surface 11b, and the pressing protrusion 12b comes into contact with the contact portion 33b as in the case of FIG. In this case, since the fulcrum of the cam follower 31b does not move, the rotation transmitting body, that is, the rotating plate 7b rotates against the spring 27b, separating the gear 9b from the large gear 26b. As a result, the transmission of rotational force to the large gear 26b is cut off (see FIG. 1).

On the other hand, due to the rotation of the rotating plate 7b, this rotating plate 7
The bent piece 13b of b is the pressure receiving part 2 of the hook member 24.
4b from the left, the hook member 24 rotates and the engaging pin 22 is pushed into the engaging portion 24b.
Cancel from. Then, the switching plate 17 returns to the right by the tension spring 23, but the right inclined edge 21a of the switching plate 17 becomes unlatched to the support body 15a as shown in FIG. Since the inclined edge 21b rotates the support body 15b in the opposite biasing direction, the right pinch roller 4a comes into pressure contact with the capstan shaft 3a, and the left pinch roller 4
b is separated from the capstan shaft 3b.

Further, the right rotating plate 7a is pulled by the spring 27a and rotates counterclockwise, thereby causing the small gear 9a of the rotation transmission body to mesh with the large gear 26a, and the tape runs to the right again. I come to do it.

Next, if it is desired to end the reproduction operation, the stop operation member 38 may be pushed in. By this operation, the magnetic head 2 returns from the operating position to the stop position, and the tape drive motor is stopped to be in a stopped state, but since this mechanism is common, a description thereof will be omitted.

On the other hand, the bulging protrusion 3 provided on the stop operation member 38 by pushing the stop operation member 38
9 slides into contact with the lower surface of the hook member 24, causing the hook member 24 to float as shown in FIG. Therefore, if the engagement pin 22 is engaged with the engagement portion 24a and the switching plate 17 is moved to the left in the state shown in FIG. When floating due to contact, the engagement pin 22 is released from the engagement portion 24a, and the switching plate 17 is returned to the right. Therefore, the next time a playback or recording operation is developed, the tape will necessarily start running to the right.

Note that the present invention is not limited to the above embodiments. For example, in the above embodiment, the stop operation member was shown as an example of the interlocking member for determining the operation start surface, but if the playback operation member or the recording operation member is provided with the function of releasing the hook member 24, the previous operation is set to the left. If the rotation ends while one reel shaft is rotating, the switching plate 17 may be switched to the right at the same time as the playback operation member or the recording operation member is pushed in at the start of the next operation.

〔Effect of the invention〕

As described above, according to the auto-reverse device for a tape recorder according to the present invention, there is no need for accessory parts such as solenoids, and the structure is therefore easy to downsize. Furthermore, the balance of the flywheel is not disturbed, and since the pinch roller switching mechanism is activated by detecting the stoppage of the reel shaft, malfunctions will not occur even if the tape tension temporarily increases during startup. Furthermore, with this auto-reverse device, the running direction of the tape is always the same at the start of operations such as playback and recording, so even if the recorded contents on both sides of the tape, A and B, have an order, it is troublesome to return to the A side. operations can be omitted.

[Brief explanation of drawings]

The figure shows one embodiment of the present invention, and FIGS. 1 to 4 are schematic configuration diagrams of an auto-reverse device;
FIG. 5 is a cross-sectional view of FIG. 4. 1a, 1b...Reel shaft, 2...Magnetic head,
3a, 3b... Capstan shaft, 4a, 4b...
Pinch roller, 7a, 7b... Rotating plate (rotation transmitting body), 8a, 8b... Large gear, 9a, 9b... Small gear, 11a, 11b... Eccentric circular cam surface, 12
a, 12b...pressing protrusion, 17...switching plate (pinch roller switching member), 22...engaging pin, 24...
...Hook member, 24a...Engaging part, 24b...Pressure receiving part, 29a, 29b...Press biasing part, 31a,
31b...Cam follower, 33a, 33a...Abutment portion, 38...Stop operation member (interlocking member for determining operation start surface), 39...Bulging protrusion.

Claims (1)

[Claims] 1 Arrange the capstan shaft, pinch roller and reel shaft symmetrically on the left and right sides of the magnetic head,
The capstan shafts on both sides and one of the reel shafts are constantly driven to rotate, and a pinch roller on the same side as the rotating reel shaft is pressed against the corresponding capstan shaft to move the magnetic tape in one direction. In an auto-reverse device for a tape recorder that automatically switches the running direction of a magnetic tape when the magnetic tape is wound to the end,
The pressing force is provided at an eccentric position on each of the reel shafts, and the reel shaft is symmetrical in that it constantly rotates under the rotational force of each capstan shaft and transmits the rotational force to the corresponding reel shaft via a friction mechanism. a rotation transmitting body, an eccentric circular cam surface and a pressing protrusion provided around the rotation axis of each rotation transmitting body,
A part of the reel shaft has a contact portion, and while the reel shaft is rotating, the contact portion is urged by the pressing urging portion to slide into contact with each of the cam surfaces. When the reel shaft stops and the contact part remains at a position away from the cam surface due to the loss of the urging force of the pressing urging part, the pressing protrusion is brought into contact with the contact part and the rotation transmitting body is moved. A symmetrical cam floor that moves to a non-engaging position with respect to the reel shaft, and a rotation transmitting body that is provided so as to be reciprocally movable and is biased in one direction, and this moving operation when one rotation transmitting body moves to a non-engaging position with respect to the reel shaft. a pinch roller switching member that shifts in the opposite biasing direction in response to the change in direction and switches the left and right pinch rollers toward and away from the capstan shaft; A hook member that locks in the moved position and releases the locking state with respect to the switching member in response to the moving operation when the other rotation transmitting body moves to a non-engaging position with respect to the reel shaft, and a hook member that stops the tape recorder. It operates in conjunction with the operation or playback or recording start operation, and when the pinch roller switching member is locked to the hook member, it is used to determine the operation start surface for releasing the locked state by urging the hook member. An auto-reverse device for a tape recorder, characterized by comprising an interlocking member.