JPS6346915Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a tension arm device for a tape recorder.
It is an object of the present invention to provide a tension recorder device for a tape recorder that can vary tension setting values.

Generally, in a tape recorder, the tension of the tape changes at startup and during tape running. Tape tension at startup varies due to reel inertia, mechanical timing, etc., and tape tension while the tape is running varies due to uneven torque of the reel motor, eccentricity of the reel, and friction between the tape and reel flange. , it fluctuates due to uneven winding of the tape, etc. For this reason, tape recorders are provided with a tension arm device that cooperates with a reel motor or the like to correct variations in tape tension.

A conventional tension arm device has a tension roller on which a tape is mounted on one end of a rotatably pivoted tension arm and applies tension to the tape, and a tension roller on the other end of the tension arm. It has a structure in which a spring is fixedly applied and the tension arm is rotated in the direction of applying the tension, and fluctuations in the tape tension while the tape is running are absorbed by the tension spring. When the tension arm is rotated against the force, the reel motor etc. are controlled in accordance with the amount of rotational displacement.

A tension arm device that is loaded with this kind of tape and controls the tape tension has a configuration that can load only a tape of a specific width dimension that must be run at a predetermined tension setting value. The disadvantage was that the tape could not be used selectively. For example, when mounting a 1/2-inch tape instead of a 1/4-inch tape, the tension setting value must be approximately doubled because the width of the tape is doubled in order to maintain a constant pressure against the tape head surface. There is a need to. However, in conventional devices, one tension spring is fixedly installed on the tension arm, and this spring uniformly biases the tension arm to rotate, so it is difficult to use 1/2 inch tape. If it is mounted, tension fluctuations cannot be absorbed, or the rotation range of the tension arm becomes large, and the control position for the reel motor etc. is also shifted. For example, a photo interrupter that detects the amount of rotation of the tension arm may The disadvantage was that the arrangement of the servo systems, etc., had to be changed.

The present invention eliminates the above-mentioned drawbacks, and an embodiment thereof will be described below with reference to the drawings.

FIG. 1 is a perspective view of an embodiment of a tension arm device for a tape recorder according to the present invention, and FIG. 2 is a plan view thereof.

The tension arm device 1 includes a support bracket 2
A tension arm 3 is rotatably supported at a central portion 3a on a support shaft 2a that is erected on the shaft, and a tape T is mounted on one end of the tension arm 3 to guide the tension arm 3. A shaft roller 3b is rotatably provided, and a pin 3c is implanted at the other end. A balance weight 3d for balancing the tension roller is provided on the lower surface near the pin 3c, so that the tension servo can be operated without any trouble even when the tape recorder is placed vertically. The support bracket 2 has stoppers 2b and 2c formed by partially protruding parts thereof,
On the other hand, both stoppers 2b are located approximately in the middle between the central portion 3a of the tension arm 3 and the tension roller 3b.
A locking pin 3e is implanted to abut on the tension arm 2c and limit the range of rotation of the tension arm 3.
A rotating plate 3f is fixed to the lower surface of the central portion 3a, and rotates integrally around the support shaft 2a as the tension arm 3 rotates. One end of the tension coil spring 4 is hung on the edge of this rotating plate 3f, and the other end is hung on the overhanging piece 2d of the support bracket 2. When the tension of the tape T is not applied to the tension roller 3b, as shown in FIG. As shown in FIG. 2, the amount of extension of the tension coil spring 4 is set to zero, and this spring 4 functions at the time of shut-off.

Pin 3 implanted at the other end of tension arm 3
c is fitted into a long hole 5a formed in one end of the connecting lever 5, and the tension arm 3 and the connecting lever 5 constitute a link mechanism. One end of a first tension coil spring 6 is hung on a pin 5b implanted at the other end of the connection lever 5, and the other end of the first tension coil spring 6 is attached to a support located on the longitudinal line of the connection lever 5. Pin 2 planted in bracket 2
It is hung on e. When the tension of the tape T is not applied to the first tension spring 6, the amount of extension thereof is set to zero, as shown in FIG.

The support bracket 2 has a support frame 7 bent and formed near the first tension coil spring 6, and a locking portion 8 having locking recesses 8a and 8b at both ends is formed on the side edge of the support frame 7. has been done. A rotating shaft 10 having a locking plate 9 is rotatably supported approximately at the center of a supporting frame 7 having a substantially U-shaped cross section. A hexagonal hole 10a is formed. A locking pin 9a is embedded in the corner of the locking plate 9, and this locking pin 9a is constantly tensioned by a tension coil spring 11.A hexagonal wrench is inserted into the hexagonal hole 10a from the outside to set the rotation axis. That is, when the locking plate 9 is rotated, the locking pin 9a is slid along the end surface of the locking portion 8 due to the toggle action of the tension coil spring 11, and the locking pin 9a is moved in sliding contact with the end surface of the locking portion 8, and the locking pin 9a is moved in sliding contact with the end surface of the locking portion 8, and the locking pin 9a is moved in sliding contact with the end surface of the locking portion 8. Since the pin 9a is locked, the locking plate 9 is moved in a click-like manner.

The locking plate 9 has a cross section of approximately L in the portion protruding from the support frame 7.
It has a letter-shaped bent portion 9b, and a slit-like elongated hole 9c is bored in this bent portion 9b. Another pin 5c is implanted on the opposite side of the connecting lever 5 from the pin 5b, and one end of the second tension coil spring 12 is hung on this pin 5c. On the other hand, the other end side of this spring 12 has a straight part 12a, and a locking ring 12b is formed at the tip of the straight part 12a.
is inserted into the slit-shaped long hole 9c.
Therefore, in the state shown in the second figure, the other end of the second tension coil spring 12 is not restrained and is a free end.

The operation of this embodiment will be explained below.

When mounting a 1/4 inch tape T, rotate the locking plate 9 clockwise as shown in FIG. 2, engage the locking pin 9a with the locking recess 8a on the right side, The tape T is mounted on the tension roller 3b. At the time of starting recording/playback, the tension arm 3 is sharply rotated counterclockwise, the first tension coil spring 6 is extended, and the resulting tension is balanced with the tension of the tape T, so that the tension arm 3 is in an equilibrium state and swings as the tension changes, controlling the tape tension while it is running. In this state, as shown in FIG. 3, the locking ring 12b of the second tension coil spring 12 is spaced apart from the bent portion 9b and is still a free end.
No action is taken on the connection lever 5, that is, the tension arm 3.

Next, when mounting a 1/2 inch tape T' on the device 1 of this embodiment, use a hexagonal wrench from the outside into the hexagonal hole 10a, and move the locking plate 9 counterclockwise as shown in FIG. Rotate. At this time, the locking pin 8a engages with the locking recess 8b, and the elongated hole 9c of the bent portion 9b is brought to a position close to the pin 2e, and the second
The locking ring 12a of the tension coil spring 12 is located at the bent portion 9.
The locking ring 12a is also brought to a position close to the pin 2e by being hooked on the slit-like elongated hole 9c of b, and the second tension coil spring 12 is aligned in the direction of the first tension coil spring 6. Note that the amount of elongation of the second tension coil spring 12 in this state is zero. When the tape T' is run, a force is applied by the tension of the tape T' to rotate the tension arm 3 in the counterclockwise direction, but the locking ring 12b of the second tension coil spring 12 is not attached to the bent portion 9b. Since the end is locked and fixed, the first tension coil spring 6 and the second tension coil spring 12 act on the connecting lever 5, that is, the other end of the tension arm 3, and the tension arm 3 is rotated. Rotate clockwise and tape
Absorbs tension fluctuations in T′. As mentioned above,
Since the spring constants of the first and second tension coil springs 6 and 12 are approximately the same, the rotational position of the tension arm 3 is the same as that when the 1/4 inch tape T is mounted. In the past, twice the rotational force is applied to the tension arm 3,
Even if a 1/2-inch tape T', which requires a tension setting value approximately twice that required for a 1/4-inch tape T, is loaded, the tension arm 3 will not move as shown in Figure 5. If the tape T' is placed in the same equilibrium position as shown in FIG. However, there is no need to change the arrangement of a servo system such as a photointerrupter that detects the amount of rotation of the tension arm 3 and sends a control signal to the reel motor or the like.

In this way, the locking plate 9 is changed as appropriate, the locking ring 12b of the second tension coil spring 12 is changed from the free end to the fixed end, the second tension coil spring 12 is made to function, and the first tension coil spring is Since the tension arm 3 is configured to rotate in such a manner that the rotation force of the second tension coil spring 12 is superimposed on the rotation force of the tension coil spring 6, even a 1/2 inch tape T' can be mounted. . Further, by simply changing the spring constant of the second tension coil spring 6, tapes of other tape widths can be mounted on the tension arm 3. Furthermore, since it is only necessary to attach the second tension coil spring 12, the locking plate 9, etc., and there is no need to improve the tension arm 3, the configuration is simple, and only a tape of a specific tape width can be mounted. This method has the advantage that it is easier to use and cheaper than using a separate tape recorder, and the tension can be changed from the outside with a simple operation using a wrench.

In the above embodiment, the locking ring 12b is used as a free end, the other end of the spring 12 is locked to the connecting lever 5, and the locking plate 9 is rotated to lock the locking ring 12b. The structure is such that the spring 12 functions as a fixed end, but the present invention is not limited to this. One end of the second spring on the locking ring side is fixed to the support bracket 2, and the other end of the second spring 12 is fixed to the support bracket 2. It is also possible to configure a locking plate or the like so that the other end is selectively locked into a locking hole provided in the connecting lever 5 and becomes a fixed end. In this case, 1/4 When the inch tape T is mounted, the other end of the second spring is a free end and is detached from the locking hole of the connecting lever 5, so that the weight of the second spring is transferred to the connecting lever 5.
In other words, there is no need to join tension arm 3, and 1/4
There is an advantage that the tension servo is good when an inch tape T is mounted.

As described above, the tension arm device for a tape recorder according to the present invention includes a tension arm that is rotatable and has a tape contacting member that applies tension to the tape at one end, and a fixed part that has one end. a first spring whose other end is locked to the tension arm and urges the tension arm to rotate in a direction to apply the tension; and a first spring whose other end is connected to the tension arm as a free end. The structure consists of a second spring, and a locking mechanism that selectively turns the free end of the second spring into a fixed end and makes the second spring function, so tapes of different widths can be replaced. It is mounted on the tension arm and absorbs tension fluctuations, allowing recording and playback to be performed without any trouble.It is easy to use, and the servo system that controls the reel motor etc. by detecting the amount of rotation of the tension arm can be adjusted. This is not necessary when replacing, as all you have to do is simply switch the locking mechanism, and furthermore, you only need to add a second spring and locking mechanism without changing the design of the tension arm itself. , the structure is simple and inexpensive, and in addition, the other end of the second spring is locked to a fixed part, and the locking mechanism locks the second spring in one rotational position. If one end of the second spring is not locked to the tension arm, but one end of the second spring is locked to the tension arm at other rotational positions, the first In the rotational position, the second spring has the advantage that its own weight does not affect the tension arm.

[Brief explanation of the drawing]

FIG. 1 is a perspective view of an embodiment of a tension arm device for a tape recorder according to the present invention, and FIGS. 2 to 5 are plan views showing the operation mode of the embodiment. DESCRIPTION OF SYMBOLS 1... Tension arm device of tape recorder, 2... Support bracket, 3... Tension arm, 3b... Tension roller, 3c... Pin, 5... Connection lever, 5a... Long hole, 6... ...First tension coil spring, 7... Support frame, 8... Locking portion, 9... Locking plate, 9a... Locking pin, 9b...
Bent portion, 9c...Slit-shaped elongated hole, 10... Rotating shaft, 10a... Hexagonal hole, 12... Second tension coil spring, 12a... Straight portion, 12b... Locking ring.

Claims (1)

[Claims for Utility Model Registration] (1) A tension arm that is rotatable and has a tape abutting member that applies tension to the tape at one end; one end is a fixed part and the other end is a tension arm; a first spring that is respectively locked to the arm and urges the tension arm to rotate in a direction that applies the tension; and a second spring that is associated with the tension arm with one end being a free end. ,
A tension arm device for a tape recorder comprising a locking mechanism that selectively makes the free end of the second spring a fixed end and causes the second spring to function. (2) the other end of the second spring is locked to a tension arm, and the locking mechanism does not lock the one end of the second spring in one rotational position; In the other rotational position, one end of the second spring is locked.
A tension arm device for a tape recorder as described in (1). (3) The other end of the second spring is locked to the fixed part, and the locking mechanism connects the one end of the second spring and the tension arm in one rotational position. A tension arm device for a tape recorder according to claim (1) of the utility model registration, wherein one end of the second spring is not locked, but is locked to the tension arm at another rotational position. .