JPS6349874Y2 - - Google Patents

Description

[Detailed Description of the Invention] Industrial Field of Application The present invention is directed to a capstan for driving a tape, etc., in a recording/reproducing device such as a video tape recorder, or in other various information processing systems, by using a pinch roller. It is a plunger device that is most suitable for application to pinch roller crimping devices that perform crimping.In particular, it is a plunger device that is ideal for application to pinch roller crimping devices that perform crimping.In particular, the movable iron core of the plunger solenoid uses suction to press a crimping body such as a pinch roller through a crimping spring to a crimped body such as a capstan. This invention relates to a plunger device configured to be elastically pressed against the plunger device.

BACKGROUND TECHNOLOGY AND PROBLEMS As is well known, a plunger solenoid attracts a movable core to a fixed core using magnetic attraction force, but the attraction force increases as the movable core approaches the fixed core. At the moment when the movable core starts suction, the movable core is far away from the fixed core, so the suction force is very weak.

By the way, in the conventional plunger device mentioned above, the crimping body is moved in the direction of crimping the body to be crimped against the crimping spring from the moment when the plunger solenoid starts suctioning the movable core. A large load is applied to the movable core of the plunger solenoid due to the repulsive force of the compression spring from the moment suction starts. On the other hand, in the plunger solenoid, as mentioned above, the suction force is very weak at the moment when the movable iron core starts suction. Therefore, in the conventional plunger device, a large suction is applied from the moment the suction of the movable iron core starts, so that the movable iron core can be reliably suctioned by overcoming the large load due to the repulsive force of the compression spring that is applied from the moment the suction of the movable iron core starts. It uses a large plunger solenoid that provides power. For this reason, in conventional plunger devices, the entire device tends to be large, and the space factor when incorporating it into equipment such as a video tape recorder is extremely poor, which severely restricts the miniaturization of equipment. Larger plunger solenoids had drawbacks such as extremely high component costs.

Purpose of the invention The present invention seeks to provide a plunger device capable of correcting the above-mentioned deficiencies.

Summary of the invention The present invention includes a rotatable first lever having the crimp body held at its tip, a second lever rotatably disposed opposite to the first lever, and one end of which is connected to the first lever. a pair of connecting links which are rotatably connected to intermediate portions of the first lever and the second lever, and whose other ends are rotatably connected to each other; A state in which the second lever is pressed against the stopper by the compression spring, comprising the compression spring that energizes the second lever and a stopper that restricts rotation of the second lever toward the first lever beyond a certain level. Then, the movable iron core of the plunger solenoid attracts the central connecting portion of the pair of connecting links to extend the pair of connecting links from a nearly doglegged bent state to a straight line. Then, the first lever is rotated with respect to the second lever to bring the crimping body into contact with the crimped body, and by the subsequent extension of the pair of connecting links, the second lever is rotated. A plunger device configured to be rotated in a direction away from the stopper against the crimping spring, so that the crimping body is crimped onto the crimped body by the repulsive force of the crimping spring at that time,
By using a small plunger solenoid, it is possible to reduce the size and cost of the entire device.

Embodiment Hereinafter, an embodiment in which the present invention is applied to a pinch roller pressure bonding device for a capstan of a video tape recorder will be described with reference to the drawings.

First, in FIGS. 1 to 5, 1 is a capstan rotatably supported on a mechanical deck of a video tape recorder and driven to rotate at a constant speed by a motor (none of which is shown); is a pinch roller that elastically presses the tape 3 onto the capstan 1. Reference numeral 4 denotes a mounting base mounted on the mechanical deck, and a pinch roller crimping device is mounted on this mounting base 4.

First, one end 6a of the first lever 6 is rotatably supported on a fulcrum shaft 5 vertically mounted on one end 4a of the mounting base 4. As shown in detail in FIG. 2, this first lever 6 is formed by pressing a sheet metal, and has a generally U-shaped cross section as a whole, with a side plate 9 between the upper and lower opposing pieces 7 and 8. The side plate 9 has an opening 10 formed approximately in the center thereof. The first lever 6 is pivotally supported on the fulcrum shaft 5 by inserting the upper and lower opposing pieces 7 and 8 through the fulcrum shaft 5 at its one end 6a side. Further, on the other end 6b side of the first lever 6, there is a support shaft 1 parallel to the support shaft 5 between the upper and lower opposing pieces 7 and 8.
1 are connected to each other, and a pinch roller 2 is rotatably supported on the outer periphery of the fulcrum shaft 11.

Next, one end 13a of the second lever 13 bent into a Z-shape is inserted through the opening 10 of the first lever 6 and inserted into the one end 6a side of the first lever 6, so that the second lever 13 is approximately halfway between the top and bottom of the fulcrum shaft 11. It is rotatably supported in the section. A pressure spring 15 made of a tension spring is bridged between the other end 13b of the second lever 13 and a spring locking pin 14 implanted on the mounting base 4, and the pressure spring 15 is connected to the second lever. Reference numeral 13 is on the first lever 6 side, which is rotated in the direction of arrow a in FIG. 3. Note that the other end 1 of this second lever 13
3b is brought into contact with a stopper 16 installed on the mounting base 4, and the rotation of this second lever 13 in the direction of arrow a is restricted beyond a certain level.

Next, at the opening 10 portion of the first lever 6, one end of each of the pair of connecting links 18, 19 connects to a connecting pin 20 connected between the upper and lower facing pieces 7, 8 at the intermediate portion 6c of the first lever 6, and a second Middle part 13 of lever 13
The other ends of these two connecting links 18 and 19 are rotatably connected to each other by a central connecting pin 22. In fact, both connecting links 1
One end 23a of the suction rod 23 is interposed between the other ends of the suction rod 23, and the central connecting pin 22 rotatably connects the suction rod 23 and both connecting links 18 and 19 to each other.

Next, a small plunger solenoid 25 is mounted on the other end 4b of the mounting base 4, and the tip of its movable iron core 26 is connected to the other end 23b of the suction rod 23 via a connecting pin 27. As shown in FIG. 3, a return spring 28 made of a tension spring is bridged between the other end 6b of the first lever 6 and the spring locking pin 14, and this return spring 28 causes the first lever 6 to is rotated in the direction of arrow b in FIG. However, this return spring 28 is a very weak spring whose only purpose is to separate the pinch roller 2 from the capstan 1, and it is hardly responsible for the load during the suction operation of the movable core 26 of the plunger solenoid 25, which will be described later. It can be ignored.

In the pinch roller crimping device configured as described above, first, FIG. 3 shows the plunger solenoid 2.
5 indicates a demagnetized state. In this state, the second lever 13 is brought into contact with the stopper 16 by the spring force of the compression spring 15, and the pinch roller 2 is separated from the capstan 1. Further, the central connecting pin 22 portion is biased to move in the direction of arrow c, and both connecting links 18 and 19 are bent into a substantially dogleg shape.

Next, FIG. 4 shows a state in which the plunger solenoid 25 is excited by being energized. That is, when the video tape recorder is switched to the recording or reproducing state, the plunger solenoid 25 is energized and the movable core 26 is attracted in the direction of arrow d. Then, the central connecting pin 22 portion is sucked in the direction of arrow c' through the suction rod 23, and both connecting links 18,1
9 is extended from the bent state shown in FIG.
and projected in the f direction. As a result, the first lever 6 is rotated in the direction of arrow b', and the second lever 13 is also rotated in the direction of arrow a' and separated from the stopper 16. At this time, the pressure spring 15 is pulled, and the second lever 13 is also rotated in the direction of arrow a'. The repulsive force of the compression spring 15 is applied to both connecting links 1
8 and 19 to the first lever 6, the pinch roller 2 pinches the tape 3 and pinches the capstan 1.
is elastically crimped.

Next, the crimping drive status of the pinch roller 2 is
To explain with reference to FIG. 7 and FIG. 7, first, the state shown by the solid line in FIG.
is fixed in contact with the stopper 16.

Next, as shown by the imaginary line in FIG. 6, the movable core 26 starts to be attracted in the direction of arrow d, and
The part starts to be suctioned in the direction of arrow c', but at the stroke S ₁ of the movable iron core 26 to start suction, the first lever 6 is moved by an angle θ ₁ turn in the direction of arrow b', and the pinch roller 2 is moved toward the capstan 1. is brought into contact with. During this levering, however, the second lever 13 maintains its fixed state in contact with the stopper 16, and no tensile force is applied to the compression spring 15. Therefore, the movable iron core 26
While the suction is started for _one minute of the stroke S, the compression spring 15 is not subjected to any suction load at all, and the movable iron core 26 is suctioned very lightly.

On the other hand, as the movable iron core 26 starts suctioning the stroke S _{for 1} minute, the movable iron core 26 approaches the fixed iron core (not shown) in the plunger solenoid 25, and thereafter the movable iron core 26 gradually increases in size. It is strongly attracted in the direction of arrow d by the suction force.

That is, as shown by the solid line in Fig. 7, the pinch roller 2
is brought into contact with the capstan 1, the movable iron core 2
6 will continue to be strongly attracted in the direction of arrow d, and by the final suction stroke _S2 , both connecting links 18 and 19 will be moved between the first lever 6 and the second lever 13. and push against each other in the directions of arrows e and f, respectively. However, at this point, the pinch roller 2 is already in contact with the capstan 1, and the rotation of the first lever 6 in the direction of arrow b' is blocked, so the virtual As shown by the line, the second lever 13 is rotated by an angle θ ₂ in the direction of the arrow a' against the compression spring 15, and the second lever 13 is separated from the stopper 16. Then, the repulsive force of the pressure spring 15 that is stretched at that time is transmitted to the first lever 6 via both connecting links 18 and 19, and as a result, the pinch roller 2 is moved by the arrow b' by the repulsive force of the pressure spring 15. being pushed in the direction of
This pinch roller 2 is elastically pressed against the capstan 1.

Note that when the video tape recorder is switched to the stopped state, the plunger solenoid 25 is deenergized by being deenergized, and the second lever 13 is moved back in the direction of arrow a by the pressure spring 15 as shown in FIG. 16 and the first
The lever 6 is moved back in the direction of arrow b, and the pinch roller 2 is separated from the capstan 1.

According to the pinch roller crimping device configured and operated as described above, in the stroke S ₁ at which suction of the movable core 26 starts, the repulsive force of the crimping spring 15 does not become a suction load of the movable core 26 at all. The repulsive force of the compression spring 15 becomes a load only at the final suction stroke _S2 of the movable core 26. However, at the time of the final suction stroke _S2 of the movable core 26, the movable core 26 has already approached the fixed core and the suction force of the movable core 26 has already been increased.
can be strongly attracted by overcoming the repulsive force of the compression spring 15.

Moreover, by pulling the central connecting pin 22 portion of the pair of connecting links 18 and 19 connecting the first lever 6 and the second lever 13 in the direction of arrow c', the first lever 6 is rotated in the direction of arrow b'. The mechanism for causing this is a so-called boosting mechanism, as shown in Fig. 8.
If the suction force of the plunger solenoid 26 to attract the central connecting pin 22 portion in the direction of arrow c' is P, then the force F acting on the connecting pin 20 portion of the first lever 6 in the direction of arrow b' is F = PB/ A cos θ, and the force F is amplified with respect to the attraction force P.

As a result of the above, according to this pinch roller pressure bonding device, the pinch roller 2 can be elastically bonded to the capstan 1 with a predetermined pressure force while using the small plunger solenoid 26.

Further, in this embodiment, by rotatably supporting the first lever 6 and the second lever 13 on the common fulcrum shaft 5, the entire pinch roller crimping device shown in FIG. Width W of solenoid 26
The pinch roller crimping device can be housed in a very small space within the device, and the entire pinch roller crimping device can be significantly downsized.

Application Example Although one embodiment of the present invention has been described above, the present invention is not limited to the pinch roller crimping device of a video tape recorder, but can be used in various devices to elastically attach various crimped bodies to various bodies to be crimped. It can be applied to various plunger devices for crimping.

Effects of the invention As mentioned above, the present invention prevents a large load due to the repulsive force of the compression spring from acting on the movable core at the time of starting suction when the suction force of the movable core of the plunger solenoid is weak. Since the plunger device is configured to elastically press the crimping body against the crimped body against the crimping spring at the final point of suction when the pressure is increased, a small plunger solenoid can be used. As a result, the entire plunger device can be downsized, and the space factor when incorporating it into equipment such as a video tape recorder is greatly improved, which not only promotes downsizing of the equipment itself, but also The plunger solenoid has low component costs and can reduce costs.

[Brief explanation of the drawing]

The drawings show an embodiment in which the present invention is applied to a pinch roller crimping device for the capstan of a video tape recorder, in which FIG. 1 is a perspective view of the entire device, and FIG. 2 shows the first lever portion. A perspective view, FIGS. 3 and 4 are plan views showing how the pinch roller is pressed against and separated from the capstan, FIG. 5 is a sectional view taken along the line in FIG. 4, and FIGS. FIG. 3 is a schematic diagram illustrating a crimping operation of a pinch roller. In addition, in the symbols used in the drawings, 1...capstan, 2...pinch roller, 3...tape, 5...fulcrum shaft, 6...first lever, 13...
Second lever, 14... Spring locking pin, 15... Pressure spring, 16... Stopper, 18, 19... Connecting link, 20, 21... Connecting pin, 22... Center connecting pin, 23... Suction Rod, 25... plunger solenoid, 26... movable iron core.

Claims (1)

[Scope of utility model registration request] In a plunger device, the crimping body is elastically crimped onto the body to be crimped via a crimping spring by suction of a movable iron core of a plunger solenoid. a second lever rotatably disposed opposite to the first lever, one end of which is rotatably connected to an intermediate portion of the first lever and the second lever, and the other end of the second lever is rotatably arranged opposite to the first lever; a pair of connecting links that are rotatably connected to each other; and the compression spring that rotatably biases the second lever toward the first lever;
and a stopper that restricts rotation of the second lever toward the first lever beyond a certain level, and the plunger solenoid is movable when the second lever is pressed against the stopper by the compression spring. By sucking the central connecting portion of the pair of connecting links with the iron core and extending the pair of connecting links from a nearly doglegged bent state to a straight position, the first lever can be moved into the above-mentioned position. The crimping body is brought into contact with the crimped body by rotating with respect to the second lever, and the second lever is moved against the crimping spring by continuing to extend the pair of connecting links. 1. A plunger device characterized in that the plunger device is configured to be rotated in a direction away from a stopper so that the crimping body is crimped onto the crimped body by the repulsive force of a crimping spring at that time.