JPH0458099B2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention detects when the reel shaft has stopped and switches the left and right pinch rollers, and
This invention relates to an auto-reverse device for a tape recorder that allows you to see the running direction of the tape at a glance.

[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 known devices in which the pinch rollers are switched using the rotational force of a wheel or the like.

[Problem that the invention seeks to solve]

A device that electrically detects the end of a tape is equipped with a solenoid, which results in a complicated structure and is disadvantageous in terms of miniaturization.

Devices that utilize the rotational force of the flywheel generally have a pin set up on a part of the flywheel, and this pin turns the pinch roller switching mechanism, which may impede the balance of the flywheel and also cause the tape to stop when starting up. Since the tension temporarily increases, there is a risk that this will be detected and cause a malfunction.

In addition, in conventional tape recorders with auto-reverse devices, especially when installed in a vehicle, the magnetic tape, reel shaft, etc. cannot be seen from the outside, so it is currently difficult to tell which direction the tape is running in. It was an unnecessary inconvenience.

[Purpose of the invention]

The present invention was made to solve these problems, and its purpose is to make it easy to downsize without the need for attached parts such as solenoids, and without the risk of disturbing the balance of the flywheel or causing malfunction. Another object of the present invention is to provide an auto-reverse device for a tape recorder that allows the running direction of the tape to be seen at a glance.

[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 connects from the capstan shaft to the reel shaft. The pinch roller switching mechanism is activated in response to the movement of the rotation transmission body when the rotation transmission body is removed from the rotation transmission position. Further, a tape direction display member is connected to the pinch roller switching mechanism, and this display member is positioned at one of two positions depending on the position of the pinch roller switching mechanism.

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 mechanism is operated, and at the same time, the position of the tape direction indicating member is switched.

With this configuration, the pinch roll switching mechanism does not operate as long as the reel shaft is rotating, and the mechanism operates when the reel shaft stops, eliminating the need for attached parts such as solenoids.
Easy to downsize.

Further, there is no risk of disturbing the rotational balance of the flywheel or causing malfunction at startup.

Furthermore, since the running direction of the tape can be seen at a glance using the tape direction display member, it is extremely convenient in usage situations where the magnetic tape, reel shaft, etc. are not visible from the outside, such as when used in a vehicle. be.

〔Example〕

The figures show one embodiment of the present invention, and FIG. 1 shows a state in which the right reel shaft 1a is rotating, and 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 respectively attached to 3b, and rotary plates 7a, 7b which are rotatable about respective capstan shafts 3a, 3b are also provided. Each rotating plate 7a,
At one end of 7b are large and small gears 8a, 8b; 9.
The rotation transmitting body consisting of a and 9b is the shaft 10a and 10b.
These shafts 10a, 10b
Eccentric circular cam surfaces 11a, 11b are formed around the shaft 1, and pressing protrusions 12a, 12b are formed at the maximum radius of each eccentric circular cam surface 11a, 11b.
0a and 10b are continuously provided in a protruding manner. The other end of each rotating plate 7a, 7b is a bent piece 13a, 13.
b.

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 denotes a switching plate that is slidable in the left-right direction, and this switching plate 17 includes the rotating plates 7a, 7b.
The protrusion 18 is sandwiched between the bent pieces 13a and 13b.
a, 18b; 19a, 19b are provided, and furthermore, bent pieces 16a,
Openings 20a and 20b are provided into which 16b is inserted. Note that inclined edges 21a and 21b are provided in a part of each opening 20a and 20b, and when the switching plate 17 moves to the right, the left inclined edge 21b is moved to the left support as shown in FIG. 15b bent piece 1
6b and pull the left pinch roller 4b away from the capstan shaft 3b, and when the switching plate 17 moves to the left, the right inclined edge 21a as shown in FIG.
is slid onto the bent piece 16a of the right support 15a, and the right pinch roller 4a is attached to the capstan shaft 3.
Pull away from a. However, each support body 15a, 15b is connected to each pinch roller 4a, 4 by a spring (not shown).
b is biased in the direction of pressing the capstan shafts 3a, 3b into contact with each other.

Further, near one end of the switching plate 17, an articulated plate 24 is connected by a deployment spring 22 and is movable articulately within a range regulated by a stopper pin 23. These articulated plates 24 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 24 rotates to a position exceeding the neutral point, This time, the reversing force of the articulating plate 24 moves the switching plate 17 to the left, thereby causing the right pinch roller 4a to be separated from the capstan shaft 3a.

Further, a tape direction display member 25 is fixed to the articulating plate 24, and the tape direction display member 25 has a position indicating the position of the tape direction display member 25, such as "F" or "R" on the outer casing (not shown) of the tape recorder. An indicator is attached to indicate the running direction of the magnetic tape.

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 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 Laid-Open No. 54-39608), 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 portions farthest from the branch 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.

Next, the effect will be explained.

In FIG. 1, the right pinch roller 4a is in pressure contact with the capstan shaft 3a, and the rotation of the capstan shaft 3a in the direction of the arrow is transmitted to the right reel through gears 5a, 8a, 9a, 26a and a friction mechanism (not shown). This shows the state in which the tape direction indicator 25 is in the "F" position, indicating that the tape direction indicator 25 is being transmitted to the shaft 1a.

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.

It is now assumed that playback or recording is being performed while a tape is being wound around the right reel shaft 1a. At this time, the left reel shaft 1b is on the payout side, so the pressing urging portion 29b does not press the pressure receiving portion 34b of the cam follower 31b. However, in this state, the left rotation transmitting body (gears 8b, 9b) has moved away from the large gear 26 and has moved to the engaged position with respect to the reel shaft 1b, and the shaft 10b is engaged with the presser auxiliary member 32b.
One side 36b of is pressed. Therefore, the other side 37b of the presser auxiliary member 32b comes to press the elastic piece 35b of the cam follower 31b, and the pressing biasing portion 29
The presser auxiliary member 32b replaces the cam follower 3.
The first contact portion 33b is held 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 the neutral point of the spring 22 is exceeded, the elasticity of the spring 22 acts in the direction of rotating the articulating plate 25. Then, switch plate 17
quickly move to the left, tape direction display member 2
5 moves to the "R" side.

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.

Note that the present invention is not limited to the above embodiments. For example, in the above embodiment, the capstan shaft 3
Gears 8a, 8b as rotation transmitting bodies with rotating plates 7a, 7b rotatable around a, 3b; 9a, 9b
However, a part of the switching plate 17, which is a part of the pinch roller switching mechanism, may be extended and the rotation transmitting body may be supported by the extended portion.
In addition, the switching plate 1 is directly connected to the member that supports the rotation transmitting body.
The switching plate 17 may be moved via another member without moving the switching plate 7. Furthermore, the tape direction indicating member is not limited to the left-right rotating type shown in the embodiment, but may also be a left-right sliding type or an articulated member 24.
It may also consist of a pair of members connected separately to both ends of.

〔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.

In addition, since the tape direction display member connected to the switching plate indicates the running direction of the magnetic tape, it can be used even when the magnetic tape, reel shaft, etc. are not visible from the outside, such as when installed in a vehicle. ,
By looking at the tape direction indicator, you can see at a glance whether the tape is running in the left or right direction.
This is extremely convenient, and many excellent effects can be obtained, such as the ability to manually switch the running direction of the tape by manually rotating the display member 25 to the left or right.

[Brief explanation of the drawing]

1 to 4 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, 8a, 8b...Large gear, 9a, 9
b... Small gear, 11a, 11b... Eccentric circular cam surface, 12a, 12b... Pressing protrusion, 17... Switching plate (pinch roller switching mechanism), 25... Tape direction indicating member, 29a, 29b... ...Press biasing section, 3
1a, 31b...cam follower, 33a, 33a
...Abutment part.

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 follower is removed from the rotation transmission position from the capstan shaft to the reel shaft, and when the rotation transmission body is removed from the rotation transmission position, the left and right pinch rollers are switched toward and away from the capstan shaft in response to the movement movement. and a tape direction display member connected to the switching mechanism and positioned at one of two positions depending on the position of the switching mechanism to display the running direction of the tape. Auto-reverse device for tape recorders.