JPH0458098B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an auto-reversing device for a tape recorder that can select whether to perform a reversing operation of a magnetic tape continuously or to automatically stop it at the end of the tape.

[Conventional technology]

Conventional auto-reversing 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 activated the flywheel. There are known devices in which the pinch rollers are switched using rotational force.

Further, although various types of automatic stop devices have been developed, there is no such device that allows an auto reverse device to also be used as an automatic stop device.

[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.

Further, if an automatic stop device is provided in addition to the auto-reverse device, the configuration becomes extremely complicated and it becomes difficult to downsize the vehicle.

[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-reverse device for a tape recorder that is free from the fear of disturbing the balance of a flywheel or causing malfunction, and which can also be used as an automatic stop device.

[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 part. 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.
In response to the operation of the rotating electric body, the pinch roller switching member is shifted in one direction or the other direction to switch between the left and right pinch rollers. In addition, by selecting one of the positions of the selection member attached to the switching member, when the switching member is shifted in one direction, the selection member urges the locking member, and the magnetic head is activated. Return to the stop position.

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 is transferred and the pinch roller switching member is activated.

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, this auto-reverse device can also be used as an automatic stop device by selecting the position of the selection member.

〔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 during which the state shown in FIG. 1 changes 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 spindles 3b, and rotary plates 7a, 7b that 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, 15b which are rotatable about 4b, and can move toward and away from the capstan shafts 3a, 3b. Moreover, each support body 15a, 15
B is also provided with bent pieces 16a and 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 a bent piece 13 of each rotating plate 7a, 7b.
Protrusions 18a, 18b; 1 so as to sandwich a, 13b;
9a and 19b are provided, and each of the supports 1
Openings 20a, 20b are provided into which the bent pieces 16a, 16b of 5a, 15b are inserted. Note that a part of each opening 20a, 20b has an inclined edge 2.
1a and 21b are provided, and when the switching plate 17 moves to the right, the left inclined edge 21b is slid onto the bent piece 16b of the left support 15 as shown in FIG. 4b from the capstan shaft 3b and the switching plate 17 moves to the left, the right inclined edge 21a is moved to the right support 1 as shown in FIG.
5a, and pull the right pinch roller 4a 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, an articulated plate 25 is provided near one end of the switching plate 17 and is movable articulately between a pair of stopper pins 23 and 24 by a deployment spring 22. These articulated plates 25 and expansion springs 22 constitute a pinch roller switching mechanism together with the switching plate 17. For example, when the switching plate 17 moves to the left and the articulated plate 25 rotates to a position exceeding the neutral point, This time, the reversing force of the articulation plate 25 moves the switching plate 17 to the left, thereby causing the right pinch roller 4a to be separated from the capstan shaft 3a.

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. In addition, these gears 9a, 26a
The meshing of the gears 9b and 26b, or the meshing of the gears 9b and 26b, is controlled by the rotation of the rotating plates 7a and 7b. Tension spring 27 in the direction of
a, 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 meshed with the gear 26a, the other gear 9b is in mesh with the gear 26a. is associated away from gear 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 due to 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, pressure receiving portions 34a, 34b located on the rotational orbits of the pressing and urging portions 29a, 29b, and an elastic portion near the fulcrum position. It has pieces 35a and 35b.

Further, the presser auxiliary member 32a is approximately L-shaped, and one side 36a, 36b is connected to the shafts 10a, 10b.
and the other sides 37a, 37
b is the elastic piece 35 of the cam follower 31a, 31b.
a and 35b.

The magnetic head 2 is attached to a head mounting plate 38 which is freely movable forward and backward, and this head mounting plate 38 is always urged in the backward direction (toward the stop position) by two tension springs 39a and 39b. A locking pin 40 as a member to be locked is protruded from the rear end of the upper surface of the head mounting plate 38, and the rear end serves as a pressing operation section 41.

On the lower surface side of the switching plate 17, this switching plate 17
A plate-shaped locking member 4 that can slide left and right parallel to the
2 is provided. This locking member 42 has a hook portion 43 corresponding to the locking pin 40, and further has a pressure receiving pin 44 on the upper surface near the hook portion 43.
, and is always biased toward the right in the figure by a tension spring 45.

On the other hand, a selection member 46 is rotatably attached to a part of the switching plate 17 with one end pivotally supported.
This selection member 46 has a pressing step portion 47 at the other end that is movable relative to the pressure receiving pin 44, and is rotated by a tension spring 48 in a direction in which the pressing step portion 47 is engaged with the pressure receiving pin 44. Forced. In the figure, 49 is a selection operation panel provided so as to be movable forward and backward. This selection operation plate 49 has an engagement pin 50 and is always urged in the backward direction by a tension spring 51. The engagement pin 50 engages with the selection member 46 and holds the selection member 46 in a position where it does not engage with the pressure receiving pin 44;
By pushing the selection operation member 49 against the spring 51, the selection member 46 rotates following the engagement pin 50, and the pressing step portion 47 moves into the pressure receiving pin as shown by the imaginary line in FIG. 44. Note that the selection operation member 49 has a locking portion 52 on its side edge.
By locking the locking portion 52 with the spring hook portion 53 of the tension spring 51, the locking portion 52 is held in the pushed-in position.

Next, the action will be explained.

In FIG. 1, the head mounting plate 38 moves forward and the locking pin 40 is attached to the hook portion 43 of the locking member 42.
At the same time, the right pinch roller 4a is brought into pressure contact with 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 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 26 and has moved to a non-engaging position with respect to the reel shaft 1b, and the shaft 10b is engaged with one side 3 of the presser auxiliary member 32b.
Press 6b and press j. For this reason, the presser foot auxiliary member 32
The other side 37b of b is the elastic piece 3 of the cam follower 31b.
5b, and instead of the pressing biasing part 29b, the presser auxiliary member 32b holds the abutting part 33b of the cam follower 31 in sliding contact with the cam surface 11b.

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 of a presses the protrusion 19a of the switching plate 17 from the right side as shown in FIG. 3, and moves the switching plate 17 to the left. Along with this, the articulating plate 25 rotates clockwise while accumulating the deployment spring 22, and when this spring 22 exceeds the neutral point, the elasticity of the spring 22 acts in the direction of rotating the articulating plate 25. Then, switch plate 1
Move 7 rapidly to the left.

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 configuration 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 playing or recording is performed. It becomes like this.

The above is a case where the reversing operation of the magnetic tape is performed continuously, and when you want to end this operation,
By a predetermined stopping operation, the locking member 42 is moved to the left in the figure against the spring 45, the hook portion 43 is removed from the locking pin 40, and the head mounting plate 38 is returned to its original position.

On the other hand, if you want to automatically stop the magnetic tape when it has been wound up to the end on the right reel during playback or recording, use the selection operation panel 49.
Just press and operate.

As shown in FIG. 5, when the selection operation plate 49 is pushed in and the locking part 52 is locked with the spring hook part 53, the selection member 46 follows the engagement pin 50 and is rotated by the spring 48. , the pressing step portion 47 is the locking member 4
It comes to be located on the side of the pressure receiving pin 44 provided in 2.

In this state, when the magnetic tape is wound up to the end on the right reel and the switching plate 17 moves to the left,
The pressing step portion 47 now pushes the pressure receiving pin 44 to the left. The locking member 42 then moves to the left,
As a result, the hook portion 43 is disengaged from the locking pin 40, and the head mounting plate 38 is returned backward by the springs 39a and 39b as shown in FIG. 6, thereby returning the magnetic head 2 to the stopped position.

In this way, when the selection operation plate 49 is pressed to automatically stop, the switching plate 17 moves to the left, so the next time you start playback or recording, the left reel will always be on the winding side. , the magnetic tape will run to the left.

〔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, this auto-reverse device can also be used as an automatic stop device by selecting the position of the selection member, and can have a variety of functions with a simple configuration.

Note that the present invention is not necessarily limited to the above embodiments. For example, when the selection member moves together with the switching plate (pinch roller switching member) and biases the locking pin (locked part), the playback operation member or the recording operation member returns, thereby returning the magnetic head to the stop position. It may be possible to restore it.

[Brief explanation of the drawing]

1 to 6 are schematic configuration diagrams of an auto-reverse device according to an embodiment of the present invention. 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...Press protrusion, 17...Switching plate (pinch roller switching member), 29a, 29b...Press biasing part, 31a, 31b...Cam follower, 33
a, 33b... Contact portion, 40... Locking pin (locked member), 42... Locking member, 44... Pressure receiving pin,
46... Selection member, 47... Pressing stepped portion.

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 the 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. When a symmetrical cam follower moves to a non-engaging position with respect to the reel shaft, and either rotation transmitting body moves to a non-engaging position with respect to the reel shaft, it shifts in one direction or the other direction in response to this movement, and rotates left and right. a pinch roller switching member that switches the pinch roller toward and away from the capstan shaft; a locked member that dislocates in conjunction with the movement of the magnetic head from a stop position to an operating position; A locking member that locks the magnetic head in a predetermined position to keep the magnetic head in the operating position and returns the magnetic head to the stop position when removed from the locked position, and the switching member that can select between two positions. a selection member that is attached to the locking member and biases the locking member to remove the locking member from the locked member only when the switching member moves in one direction with one position selected. This is an auto-reverse device for a tape recorder that is characterized by: