JPH0454584Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a tape loading device that is most suitable for application to, for example, a video tape recorder.

[Summary of the idea]

In this invention, a worm rotatably driven by a motor rotates a worm wheel through the compression repulsive force of a compression coil spring, and a loading arm driven by the worm wheel moves the tape guide to the unloading position. In a tape loading device configured to drive the loading arm from the worm wheel to the loading position, when the loading arm is driven by a worm wheel or a drive member driven by the worm wheel, an oversized spring constituted by a spring stronger than the compression coil spring is used. By driving the loading arm via a tension-absorbing spring, the tape, tape guide, and peripheral mechanisms can be safely protected in the event that excessive tension is applied to the running tape.

[Conventional technology]

Regarding a tape loading device for a video tape recorder, the applicant of the present invention
58-114044), and the reference example shown in Figures 4 and 5 is an improvement on that earlier application.

This reference example includes a drive shaft 1 that is rotationally driven by a motor, and a worm 2 that is movably attached to the outer circumference of the drive shaft 1 in a state where rotational force can be transmitted from the drive shaft 1. , a pair of compression coil springs 3a and 3b attached to the outer periphery of the drive shaft 1 to press and urge the worm 2 in the axial direction, a worm wheel 4 rotationally driven by the worm 2, and the worm wheel 4. This tape loading device is equipped with a loading arm 6 which is driven by a motor to drive a tape guide 5 from an unloading position to a loading position. A drive pin 8 attached perpendicularly to the drive shaft 2 is inserted into a long hole 10 along the axial direction provided in the shaft hole 9 of the worm 2, and the drive shaft is connected to the drive shaft through this drive pin 8. 1 is transmitted to the worm 2. Further, the pair of compression coil springs 3a and 3b are connected to the worm 2 on the outer periphery of the drive shaft 1.
These compression coil springs 3a, 3b are attached to the respective pairs of stopper rings 11a, 11b, 12 attached to the drive shaft 2.
A pair of washers 13a and 1 between a and 12b, respectively.
3b, 14a, and 14b.
Further, the worm wheel 4 is rotatably attached to a support shaft 15, and the loading arm 6 is fixed to the worm wheel 4 with a plurality of screws 16. Further, the tape guide 5 is moved along a guide rail 18 on a moving base 19.
A pair of guide pins 2 are attached to the lower part of the moving table 19.
0a and 20b are guide grooves 21 of the guide rail 18
It is configured to be guided by. A connecting pin 22 is attached to the tip of the loading arm 6.
The tip of the link 23 connected via the guide pin 20a is connected to one of the guide pins 20a.

According to this reference example, first, during loading, the drive shaft 1 is driven to rotate in the direction of arrow a by the forward rotation of the motor, and the worm wheel 4 is driven to rotate in the direction of arrow b by the worm 2. , the loading arm 6 is driven integrally with the worm wheel 4 in the same direction. Then, the moving table 19 is driven along the guide rail 18 via the link 23, and the tape guide 5 is moved as shown in FIG.
It is driven in the direction of arrow c from the unloading position shown by the dotted chain line to the loading position shown by the solid line. As a result, the magnetic tape 25 is pulled out from inside the tape cassette (not shown) by the tape guide 5 to the outside of the tape cassette.
The vehicle is loaded onto a predetermined running path that spans the road.

At this time, when the tape guide 5 is moved to the loading position, as shown by the solid line in FIG. The loading arm 6 is also stopped via the link 23. However, the drive shaft 1, which is rotationally driven by the motor, continues to be over-rotated in the direction of arrow a and then stopped. and,
Due to this overrun rotation of the drive shaft 1, the worm 2 moves one of the compression coil springs 3a to the washer 1.
The compression coil spring 3a is moved in the direction of arrow d on the drive shaft 1 while being compressed between the coil springs 3a and 14a.
The movable table 19 is pressed against the stopper 28 by the compressive repulsion force. As a result, the tape guide 5 is positioned at the loading position, and loading is completed.

Note that during unloading, the drive shaft 1 is driven to reverse rotation in the direction of arrow a' by the reverse rotation of the motor, and the loading arm 6 is driven by the worm 2 in the direction of arrow b' via the worm wheel 4. , the tape guide 5 is moved from the loading position indicated by the solid line in FIG.
It is driven in the direction of arrow c' to the unloading position shown by the dotted chain line. Then, due to the overrun rotation of the drive shaft 1 after the movable table 19 contacts the stopper 29 on the other end of the guide rail 18, the worm 2 compresses the other compression coil spring 3b in the direction of arrow d'. , the movable table 19 is pressed against the stopper 29 by the compressive repulsion force.

[Problem that the invention attempts to solve]

In this reference example, when excessive tension is applied to the running magnetic tape 25 due to some abnormality while the magnetic tape 25 is running, the worm 2 on the drive shaft 1 is moved against the compression coil spring 3a. The tape guide 5 can be moved (released) in the direction of arrow d from the position indicated by the solid line to the position indicated by the dashed-dotted line in FIG. It is made to escape in the direction of arrow c′, which is the unloading direction, to the position.

However, the distance l ₁ that the tape guide 5 can escape in the direction of arrow c' is limited by the maximum compression amount of the compression coil spring 3a. That is, the compression coil spring 3
When a is compressed to the maximum between washers 13a and 14a, the worm 2 will no longer be compressed by the arrow d.
At the same time, the tape guide 5 is also unable to escape in the direction of arrow c', and the impact energy of the magnetic tape 25 due to the excessive tension cannot be sufficiently absorbed.

Therefore, in this reference example, when excessive tension is applied to the magnetic tape 25, the magnetic tape 25 is stretched or cut, the tape guide 5 is deformed such as inclination, and the peripheral mechanism (in this case, the worm 2 or the worm wheel 4 etc.) could easily occur.

In this reference example as well, if a sufficiently long compression coil spring 3a is used to increase the amount of movement of the worm 2 in the direction of arrow d, the distance l that the tape guide 5 can escape in the direction of arrow c' can be increased. ₁ can be made large, and the impact energy of the magnetic tape 25 due to excessive tension can be sufficiently absorbed.

However, if such a long compression coil spring 3a is used, the space factor becomes worse and the tape loading device becomes larger, so there is a limit to the length of the compression coil spring 3a.

Therefore, the present invention is designed to allow the tape guide to escape by a large distance in the unloading direction when excessive tension is applied to the tape while it is running.

[Means for solving problems]

In the above-described tape loading device, the present invention provides for an excessive tension absorbing spring constituted by a spring stronger than the compression coil spring to be connected to the worm wheel or a drive member rotationally driven by the worm wheel and the loading arm. The worm wheel or drive member drives the loading arm from the unloading position to the loading position via the excessive tension absorbing spring.

[Effect]

According to the present invention, when excessive tension is applied to the running tape, the worm moves against the compression coil spring and the tape guide escapes a little in the unloading direction, but the compression coil spring is compressed to the maximum. After the tape guide is released, the tape guide can escape in the unloading direction against the excessive tension absorbing spring, and the distance over which the tape guide can escape in the unloading direction against the excessive tension can be increased.

〔Example〕

Below, an embodiment in which the present invention is applied to a tape loading device for a video tape recorder will be described.
This will be explained with reference to FIGS. Note that the same reference numerals are given to the same structural parts as those of the reference example shown in FIGS. 4 and 5, and the explanation thereof is omitted.

First, in FIGS. 1A and 1B, the loading arm 6 is rotatably supported around a support shaft 15 so that the loading arm 6 can rotate relative to the worm wheel. . A pin 33 integrally provided on the worm wheel 4 is loosely fitted into an arcuate hole 34 centered on a support shaft 15 provided on the loading arm 6. Both ends 35 of an excessive tension absorbing spring 36 constituted by a tension coil spring 35
a, 35b to the pin 3 integrated with the worm wheel 4
3 and a pin 37 integral with the loading arm 6. This excessive tension absorbing spring 36 is made of a spring stronger than the compression coil spring 3a. The loading arm 6 is rotationally urged in the direction of arrow b, which is the loading direction, with respect to the worm wheel 4 by the spring 36, and the pin 33 is inserted into the circular arc hole 34 as shown by the solid line in FIG. 1A. Rotation in the direction of arrow b is restricted by contacting one end 34a.

According to this tape loading device, first,
During loading, as shown in FIG. 1A, the drive shaft 1 is driven to rotate forward in the direction of arrow a by the forward rotation of the motor, and the worm wheel 4 is driven to rotate in the direction of arrow b by the worm 2. The loading arm 6 is driven in the direction of arrow b by the worm wheel 4 via the excessive tension absorbing spring 36. Then, the moving table 19 is driven along the guide rail 18 via the link 23, and the tape guide 5 is driven in the direction of arrow c from the unloading position shown by the two-dot chain line to the loading position shown by the solid line. As a result, the tape guide 5 pulls out the magnetic tape 25 from inside the tape cassette to the outside of the tape cassette, and loads it onto a predetermined running path stretched over tape guides 26, 27, etc. as shown by solid lines.

At this time, as shown by the solid line, when the tape guide 5 is moved to the loading position and the moving table 19 is brought into contact with the stopper 28 by the V groove 30 and stopped, the worm is 2 moves in the direction of arrow d on the drive shaft 1 to compress the compression coil spring 3a, and the tape guide 5 is positioned at the loading position by the compression repulsion force of the compression coil spring 3a.

Next, when excessive tension is applied to the magnetic tape 25 while it is running, the worm 2 first acts on the compression coil spring 3a as shown by the dashed line in FIG. 1A.
The tape guide 5 escapes in the direction of the arrow d against the arrow d, and moves the tape guide 5 from the loading position indicated by the solid line to the position indicated by the dashed-dotted line in the direction of the arrow c', which is the unloading direction, the same distance l ₁ as in the reference example described above. Just run away.

Next, after the compression coil spring 3a is compressed to the maximum, the loading arm 6 is moved against the excessive tension absorbing spring 36 (by pulling the tension coil spring 35) as indicated by the dashed line in FIG. 1B. The tape guide 5 rotates in the direction of arrow b' from the position (same position as the one-dot chain line in Figure 1A) to the solid line position, and the tape guide 5 moves to the one-dot chain line position in Figure 1B (one point in Figure 1A). The unloading direction is the unloading direction, which is the direction of arrow c', from the same position as the chain line position) to the solid line position, by a distance l ₂ minutes.

That is, according to this tape loading device,
Compression coil spring 3 for positioning the tape guide 5
When the compression coil spring 3a and the excessive tension absorbing spring 36 are used in series and excessive tension is applied to the running magnetic tape 25, the compression coil spring 3a
The excessive tension absorbing spring 36 absorbs the excessive tension in two stages, allowing the tape guide 5 to escape from the loading position by a large distance (l ₁ +l ₂ ) in the direction of arrow c', which is the unloading direction. .

Note that when the tension of the running magnetic tape 25 is restored to normal tension, the tape guide 5 is moved from the solid line position in FIG. 1B by the spring force of the excessive tension absorbing spring 35 and the compression coil spring 3a. It immediately returns to the loading position indicated by the solid line in Figure 1A in the direction of arrow c, which is the loading direction.

Next, FIGS. 2 and 3 show a modification of the excessive tension absorbing spring 36.
The figure shows a compression coil spring 39 inserted between the pin 33 in the circular arc hole 34 and the other end 34b;
FIG. 3 shows a torsion coil spring 40 inserted into the outer periphery of the support shaft 15, with both ends 40a and 40b locked to a pin 33 integrated with the worm wheel 4 and a pin 41 integrated with the loading arm 6. It is.
Note that both of these springs 39 and 40 are constructed to be stronger than the compression coil spring 3a, and these springs 39 and 40 cause the loading arm 6 to move in the direction of arrow b in the loading direction with respect to the worm wheel 4. It is rotationally energized in the direction.

Although the embodiments of the present invention have been described above, the present invention is not limited to the embodiments, and various effective changes can be made based on the technical idea of the present invention.

For example, in the embodiment, the loading arm 6 is directly rotationally driven by the worm wheel 4, and an excessive tension absorbing spring is provided between the two, but the driving member rotationally driven by the worm wheel 4 The loading arm 6 may be rotationally driven by the driving member, and an excessive tension absorbing spring may be provided between the driving member and the loading arm.

Furthermore, the present invention is not limited to tape loading devices for video tape recorders, but can be applied to tape loading devices for various recording and reproducing devices, information processing devices, and the like.

[Effect of idea]

As mentioned above, when excessive tension is applied to the running tape, the present invention moves the worm against the compression coil spring to allow the tape guide to escape a little in the unloading direction. After being compressed, the tape guide can be released in the unloading direction against the excessive tension absorbing spring, and the distance in which the tape guide can escape in the unloading direction against the excessive tension can be increased. Therefore, the impact energy of the tape due to excessive tension can be sufficiently absorbed. Therefore, it is possible to prevent stretching or cutting of the tape, deformation such as inclination of the tape guide, and damage to peripheral mechanisms due to excessive tension applied to the tape, resulting in high safety.

However, according to the present invention, there is no need to use a particularly long compression coil spring for positioning the tape guide at the tape loading position, so the space factor is good and the tape loading device becomes larger. Not at all.

[Brief explanation of the drawing]

1A to 3 show an embodiment of the tape loading device of the present invention, FIGS. 1A and 1B are overall plan views, and FIGS. 2 and 3 are modified examples. FIG. 3 is a plan view showing main parts. FIG. 4 is an overall plan view showing a reference example, and FIG. 5 is a developed cross-sectional view of the same. In addition, in the symbols used in the drawings, 1... Drive shaft, 2... Worm, 3a... Compression coil spring, 4... Worm wheel, 5... Tape guide, 6... Loading arm, 25... Magnetic Tape, 36... Spring for absorbing excessive tension.

Claims (1)

[Claims for Utility Model Registration] A drive shaft rotationally driven by a motor, a worm attached to the outer periphery of the drive shaft so as to be movable in the axial direction in a state capable of transmitting rotational force from the drive shaft; a compression coil spring attached to the outer periphery of the drive shaft to press and bias the worm in the axial direction;
A tape loading device comprising a worm wheel rotationally driven by the worm, and a loading arm driven by the worm wheel to drive a tape guide from an unloading position to a loading position, An excessive tension absorbing spring constituted by a spring stronger than the compression coil spring is provided between the worm wheel or a drive member rotationally driven by the worm wheel and the loading arm, and the worm wheel or the drive member A tape loading device characterized in that the loading arm is driven from an unloading position to a loading position via an excessive tension absorbing spring.