JPH0548265Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Field of Application of the Invention] The present invention relates to a recording/playback device such as a magnetic tape recorder, and is particularly applicable to a cassette-type tape recorder in which a tape is pulled out from a cassette and recorded and played back using, for example, a rotating head. This is related to mode switching.

[Background of the idea]

When switching modes with one cam, it is necessary to switch modes with a small rotation angle in order to use the cam effectively. By the way, conventionally, mode switching was performed only by a cam. Therefore, not only does the cam body become larger, but if a certain amount of displacement is attempted along the cam, the rotation angle of the cam becomes large. In order to miniaturize equipment, cams had to be used for multiple purposes, which posed a problem.

[Purpose of invention]

The purpose of the present invention is to eliminate the drawbacks of the above-mentioned prior art,
To provide a mechanism that can take a large amount of displacement even with a small rotation angle of a cam when changing modes such as playback, fast forwarding, and rewinding.

[Summary of the idea]

In order to achieve this object, the present invention includes a rotary body provided with a pin, a lever such as a rotating lever or a slide lever provided with a rotatable claw, and one end of which is locked to the lever so that the claw can be rotated. a spring biased in one direction, the pawl is arranged in the rotation locus of the pin so that the pin can be engaged with the pawl, and when the rotating body moves forward, the pin pushes the pawl. When the rotating body moves backward, the pawl moves in the rotational direction of the pin, and the lever switches the movement mode. When the pawl and the pin engage, the pawl moves in the direction in which the pin rotates. Even if the pin is displaced relative to the lever, the spring causes the pawl to swing and the pin and the pawl are in pressure contact with each other.

[Example of idea]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a plan view of the magnetic recording/reproducing apparatus, in which a take-up reel shaft 3 and a supply reel shaft 4 for a cassette 2 are set on a chassis 1. When the cassette 2 is set at a predetermined lowering position, the two guide rollers 6, 7 and the pinch roller 8, which were housed in the drawer opening 5 provided in the cassette 2, pull out the tape 9, wrap it around the rotating head 10, and pinch it. The roller 8 presses against the capstan shaft 11 and the tape starts running. First, this operation will be explained with reference to FIGS. 5 and 6. Furthermore, the second
3 are front views drawn to show the height relationship of each component in FIG. 1, and the positions of the components are not necessarily the same as in FIG. 1.

In FIG. 6, guide rollers 6 and 7 are attached to loading blocks 12 and 13, respectively, and inclined posts 14 and 15 are attached to these loading blocks 12 and 13, respectively, and guide grooves 16 and 15 provided in the chassis 1 are attached to the guide rollers 6 and 7, respectively. 17 so as to be able to move without slipping off. On the other hand, crank levers 21 and 22 are rotatably provided between rotary levers 19 and 20 that are rotatably mounted around a shaft 18 provided on the chassis 1 and loading blocks 12 and 13, respectively. The rotational movement of the rotary levers 19, 20 is converted into a reciprocating movement of the loading blocks 12, 13 along the guide grooves 16, 17. These rotating levers 19,
As a means for applying rotational force to the chassis 20, a spring 27 is attached to the rotating levers 25 and 26, which are rotatably attached to the chassis 1 so as to be rotatable about shafts 23 and 24.
28, the rotational lever 25 applies rotational force in the counterclockwise direction in the drawing by the spring 27 around the shaft 23, respectively.
Further, the rotating lever 26 applies a rotational force in the clockwise direction in the drawing by a spring 28 around the shaft 24, and the pins 29, 30 provided in the rotating levers 25, 26 are connected to the elongated holes 31, 32 provided in the rotating levers 19, 20. In other words, the force of the springs 27 and 28 can be used. At this time, the rotating lever 19 receives a force in the clockwise direction in the drawing from the rotating lever 25 with the shaft 18 as a fulcrum, and the rotating lever 20 receives a force in the counterclockwise direction in the drawing from the rotating lever 26. Further, the rotary lever 25 is provided with a Daruma-shaped Daruma hole 33, into which a pin 34 provided on the rotary lever 26 is inserted.
is inserted into the structure to regulate each other's movements. In FIGS. 5 and 6, the cam 35 shown in FIG. 1 is not shown because it makes the drawings difficult to see, but in FIG. The rotating lever 25 is prevented from rotating by the pin 34, and the rotating lever 25 is kept in a balanced state.

Here, the cam 35 rotates through a worm 38 driven by a loading motor 37, a worm wheel 39, and gears 40 and 41 as shown in FIG. The cam 35, loading motor 37, worm wheel 39, and gears 40, 41 are attached to a sub-shear 42 (see FIG. 2).

In FIG. 4, the cam 35 is connected to the sub chassis 42.
The cam 35 is shown attached to a shaft 43 provided on the cam 35, and the cam 35 is provided with a contact piece 44 that contacts the printed circuit board 45 and detects the presence or absence of a signal by the rotation of the cam 35 to control the loading motor 37. This allows accurate positioning of the cam 35 (the circuit diagram is not shown). The position of the cam before mounting the cassette is as shown in FIG. 8, and the position of the rotary lever at this time is as shown in FIG.

The regeneration state is when the cam 35 is rotated counterclockwise in the drawing from the state shown in FIG. 8 around the shaft 43 to the state shown in FIG. It is crimped. The position of the rotary lever 26 corresponding to the position of this cam is shown in FIGS. 1 and 5. To get to this point, as mentioned above, load block 12,
13 is a guide groove 16, 17 by springs 27, 28.
When the loading blocks 12 and 13 are in the position shown in FIG. As the loading blocks 12 and 13 move, the tape 9 is hooked and pulled out from the cassette.
13 is stopped by the stoppers 46, 47 waiting near the ends of the guide grooves 16, 17, at which point the rotary head 10 is wound as necessary. At this time, when the loading blocks 12 and 13 stop, the rotating levers 25 and 26 also stop rotating. At this time, the amount of rotational movement of the rotary levers 25 and 26 may vary due to variations in parts, loading block 12,
13 is not necessarily the same due to adjustment of the stop position of 13, etc., so the pin 34 provided on the rotating lever 26 described above is the same as the daruma hole 33 provided on the rotating lever 25.
Move to the larger hole, and tighten both rotary levers 25,
After 26 has stopped, even if one of the rotary levers is moved a little, the other rotary lever will not be moved. That is, at this point, the loading block 12 is pressed against the stopper 46 by the force of the spring 27, and the loading block 13,
Pressure-bonding to the stopper 47 can be performed by the force of the spring 28, which is a stable pressure-bonding method. At this time, the cam 35 is of course stopped at a position slightly apart from the slide surface 36 for pushing the rotary lever 26, and the cam 35 stops the rotation of the rotary lever 26 and the loading block 13 is moved to the stopper 47.
There is no way that it won't be crimped. Conversely, in order to move the loading blocks 12, 13 to the ends of the guide grooves 16, 17 on the opposite side where the stoppers 46, 47 are provided, it is sufficient to go through the reverse process described above. In other words, if the cam 35 is reversed, the cam 35 will first hit the sliding surface and move the rotating lever 26 to the shaft 24.
Rotate counterclockwise in the drawing against the force of the spring 28. If the pin 34 hits the edge of the Daruma hole 33 when it rotates, the springs 27, 2 will be attached to the cam 35.
8 will be applied, but it is clear from the above explanation that if the cam 35 is rotated as it is, the state shown in FIG. 6 will be achieved.

Next, mode switching between pinch roller pressure bonding, regeneration, and fast forwarding will be explained. To explain the structure of the parts in FIGS. 1 to 4, the pinch roller 8
The tape guide post 48 is mounted on a pinch roller bracket 50 which is rotatably mounted about an axis 49 on the chassis 1. On the other hand, a spring 52 is hung between the tension bracket 51 and the pinch roller bracket 50, which are rotatably mounted around the same shaft 49, and the pinch roller brackets are rotated clockwise in the drawing. The tension bracket 51 stops when the stopper 53 provided on the tension bracket 51 contacts the pinch roller bracket 50 while pulling each other in the counterclockwise direction, but when the tension bracket is rotated clockwise in the drawing with the pin 54 around the shaft 49, the pinch roller When the bracket starts to rotate and the pinch roller 8 hits the capstan shaft 11, the rotation of the pinch roller bracket 50 stops, but the tension bracket 51 continues to rotate and the stopper 53 separates from the pinch roller bracket 50. At this time, the pinch roller 8 is pressed against the capstan shaft 11 by the spring 52. The pin 54 is attached to a rotating lever 55 that is attached to be rotatable about the shaft 49. Between this rotary lever 55 and the cam 35 are two connecting plates 56, 5.
7, the connecting plate 56 is rotatably attached to the cam 35 and the connecting plate 57, and the connecting plate 57 is rotatably attached to the connecting plate 56 and the rotating lever 55. The pinch roller bracket 50 is provided with an elongated hole 58, into which a pin 60 on a connecting plate 59 rotatably attached to the rotary lever 26 is slidably attached so as to move in conjunction with the movement of the rotary lever 26. The pinch roller bracket 50 functions to be returned to its original position, but these movements will be described later, and the component configuration will be explained a little more here.

The rotary lever 61 is rotatably mounted around the same shaft 23 as the rotation center of the rotary lever 25, and the pin 64 attached to the control plate 63 is constantly rotated counterclockwise in the drawing by a spring 62. Since the control plate 63 is engaged with the elongated hole 65 of the
The movement of is stopped at a position regulated by the end of an elongated hole 66 provided in the chassis 1. Also, the lock plate 69, which is given a rotational force clockwise in the drawing by a spring 68 around a shaft 67 provided on the rotary lever 61, is stopped when the stopper 70 of the lock plate 69 hits the rotary lever 61, and the cam 35 is stopped. It is waiting for the provided pin 71 to rotate.

Figure 3 shows the path for transmitting the output taken out from the capstan shaft 11 to the reel. The capstan shaft also serves as a motor shaft, with a pulley 72 attached to the tip of the capstan shaft and a pulley idler 73 placed near the reel. Power is transmitted to the next idler 75 by a belt 74 stretched between them. A spring 7 is attached to the mounting shaft 76 of the idler 75.
An arm 78 biased upward in the figure at 7 is attached so as to be slidable along the shaft 76, and a two-stage gear 80 having a friction mechanism between the arm 78 and the arm 78 with a spring 79 at the tip end is attached to the two-stage gear 80. It is installed so that the large gear part and the idler gear mesh with each other. The arm 78 is held down by the control plate 63, and when it is in the position shown in FIG. The large gear winds the tape without slack while sliding, and is used when releasing tape loading. Although not shown in FIG. 3, in the reproducing state, the supply reel 4
The supply reel is driven by rotating the idler 75 in a direction in which it engages with a take-up reel having the same structure. Next, when the control plate 63 is moved to the left in the drawing, the arm 78 is pushed down by the control plate 63, and the engagement between the reel large diameter gear and the small diameter gear of the two-stage gear 80 is broken, and the reel small gear and the two-stage gear 80 are disengaged. It is possible to change the reduction ratio of transmission to the reel by shifting to the meshing with the large diameter gear part. This becomes a fast forward mode, a rewind mode, etc., and each time these modes are changed, the control plate 66 is moved left and right, but at this time, the brakes 81 and 82 are momentarily activated to prevent the reel from sagging.

Next, let's look at the movement of the pinch roller bracket based on Figures 7, 8, and 9. FIG. 8 shows a state in which the pinch roller 8 is inside the tape 9, and at this time the pinch roller bracket 50 is pulled counterclockwise in the drawing about the shaft 49 by the pin 60. The connection plate 56 linked to the cam 35 until the regeneration state shown in FIG.
57, etc., resulting in FIG. 7. At this time, the shaft 43 of the cam 35 and the connections 56, 57 are aligned substantially in a straight line, and the amount of rotation of the rotary lever 55 is maximized, and the pinch roller 8 is also pressed against the capstan shaft 11. At this time, the pin 71 has reached the position where it engages with the lock plate 69, and when the cam 35 is further turned counterclockwise in FIG.
1, the lock plate 71 is pushed. Then, a force acts on the lock plate 69 that is rotatably supported by the rotary lever 61 in a counterclockwise direction about the shaft 67, but this force is balanced by the spring 68 on the rotary lever 61.
The rotation lever 61 and the lock plate 69 are substantially integrated by the angle between the rotation lever 61 and the lock plate 69 (the angle changes depending on the position of the rotation lever 61).
In addition, since the force acting on the rotary lever 61 from the pin 71 via the lock plate 69 has a vector in the clockwise direction of the rotary lever 61, the rotary lever 61 is rotated clockwise in FIG. Then, by operating the rotary lever 61 and the control plate 63, the mode changes from the playback state to the rewinding state. At this time, connecting plate 5
Since the elongated hole 83 provided in 6 is regulated by a pin 84 provided in sub chassis 42, a small rotation angle of cam 35 can produce a large amount of displacement on the connecting plate 57 side. In other words, the pressure of the pinch roller can be released by using a small rotation angle of the cam. Here, to explain the flow of the tape 9 in FIG. 1, the tape that has left the supply reel shaft 4 is a fixed post 85, a tension post 86, a guide roller 6, an inclined post 14, a rotary head 10, an inclined post 15, a guide roller. 7, fixed post 87,
It passes through the pinch roller 8, capstan 11, and guide post 48, and is then wound onto the take-up reel shaft 3.

[Function and effect of the idea]

As explained above, according to the present invention, even if the rotating body rotates and the position of the pin changes, the claw is swung by the spring and the pin and the claw are in pressure contact. It is no longer necessary to construct a four-bar link using a lever, and only one pin and one lever are required instead of a cam, reducing the number of parts, simplifying the configuration, and making the device smaller as a whole. and reliable operation. Further, a large amount of displacement can be obtained with a small rotation angle, and therefore many modes can be set.

[Brief explanation of the drawing]

Fig. 1 is a plan view of a magnetic recording/reproducing device according to an embodiment of the present invention, Figs. 2 and 3 are plan views showing the height relationship of each component in Fig. 1, and Fig. 4 is a cam. , a printed circuit board, and an exploded perspective view showing the sub-chassis; Figures 5 and 6 are diagrams showing different operating states of the mechanism centering on the rotary lever; Figures 7, 8, and 9
The figures are diagrams showing different operating states centered on the cam. 25, 26...Rotary lever, 35...Cam.

Claims (1)

[Scope of claim for utility model registration] A rotating body provided with a pin, a lever such as a rotating lever or a slide lever provided with a rotatable claw,
a spring whose one end is locked to the lever and urges the pawl in one direction, the pawl is arranged in the rotation locus of the pin so that the pin can be engaged with the pawl, and the rotating body When the rotating body moves forward, the lever moves in the direction in which the pin pushes the pawl, and when the rotating body moves backward, the pawl moves in the rotational direction of the pin, and the lever changes the movement mode; When the pawl and the pin are engaged, the spring causes the pawl to swing even if the pin is displaced with respect to the lever, and the pin and the pawl are in pressure contact with each other. Recording and playback device.