JPH0229542Y2 - - Google Patents

Description

[Detailed Description of the Invention] (a) Field of Industrial Application The present invention relates to an improvement of a guide link, which is a component of an idler drive device for driving a reel stand of a magnetic recording/reproducing device. (B) Conventional technology Conventionally, an idler drive device for press-contacting a reel stand has a master gear, a guide arm having a guide pin that engages with a cam portion provided on the master gear, and a guide arm provided on the guide arm. It consisted of an idler mounting piece having a pivot shaft that engaged with a flat spring, and an idler installed on the idler mounting piece. In operation, an idler that receives the rotational force of the motor indirectly or directly comes into pressure contact with the reel stand, thereby rotating the reel stand and contributing to the running of the magnetic tape. At this time, the cam part provided on the master gear has an outward path and a return path, and in order to reliably trace the outward path and return path, it is necessary to apply pressure contact force to the guide pin in the direction of the surface of the master gear. This pressing force was applied by a spring provided on the guide arm. However, it has been extremely unreasonable to attach a spring to the guide arm in order to reduce the number of parts and make the body of a general magnetic recording/reproducing apparatus more compact. In addition, the workability is very poor in the parts installation process, and a separate part called a spring is used.
The cost had also become somewhat high. (c) Purpose of the present invention The purpose of the present invention is to reduce the number of parts and reliably drive the idler in an idler drive device that drives the reel stand of a magnetic recording and reproducing device. (D) Configuration The configuration of the present invention includes a motor that rotates in forward and reverse directions, a first cam groove formed in a concentric arc shape, and a cam groove continuous to the first cam groove that is bent in the radial direction and bent in a V-shape. a master gear having a second cam groove formed on an inclined surface from the middle and connected to the first cam groove with a step; and a guide pin at one end that follows the first and second cam grooves. A guide link having a pressing portion at the other end and rotatably supported by a shaft, and a rotatable idler for transmitting the rotation of the motor are mounted, and the guide link is biased in one direction opposite to the pressing portion. An idler drive device comprising an idler mounting piece, wherein one end of the guide link is formed in the shape of a leaf spring that is flexible in the direction of the support shaft, and the guide pin is always in contact with the cam groove. It is. (E) Embodiment Fig. 1 is a plan view of a guide arm according to an embodiment of the present invention, Fig. 2 is a sectional view and a partial perspective view of the guide link, and Fig. 3 is a plan view and a partial sectional view of the master gear. 4 and 5 show an embodiment of the invention. In Figs. 1 to 5, 1 is a guide link rotatably supported on a chassis 19 by a support shaft 4;
A pin 2 that engages with and follows a cam groove (to be described later) is firmly implanted at one end, and its tip is parallel to the chassis 9 surface so that it can move in the axial direction of the support shaft 4 relative to the chassis 19 surface. Flexible spring parts 6 and 7 are formed, and the other end is provided with a pressing part 5 formed of a plate spring or the like. Note that the pressing portion 5 may be integrally formed of plastic material. 8 is a coil spring that urges the guide link 1 to rotate in the CW (clockwise) direction. Reference numeral 9 denotes a master gear, and the outer periphery of the gear 9 has a first arc-shaped cam groove with one end and a second cam groove formed in the radial direction with the other end continuous with the first cam groove 10a.
Continuing from the second cam groove 10b, a third cam groove 10c becomes an inclined plane 10e from point D on the way and is connected to the first cam groove 10a with a step at point E. Integrated chassis 19
It is rotatably supported by a shaft and rotationally driven by a drive source (not shown). 13 is an idler mounting piece in which the idler 11 is rotatably supported by a pin 12;
C. with the pivot 14 provided on the idler mounting piece 13.
The pin 12 is rotatably supported by a guide arm 15 biased in the W direction, and the pin 12 is loosely fitted into a guide groove 20 cut into the chassis 19. 16,1
7 is a reel stand, and 18 is a pulley of a reel motor. Next, the operation of the idler drive device of the present invention will be explained. First, when the magnetic recording/reproducing device is in a stopped state, the cam groove 10 provided in the master gear 9 shown in FIG.
Above, the guide pin 2 is located at point A. As a result, as shown in FIG.
Since it is in contact with the idler mounting piece 13, the idler mounting piece 13 is pushed upward. At this time, the pressing part 5
Since it is formed of a leaf spring, a certain pressing force is applied to the idler mounting piece 13, and the idler mounting piece 13 is in a state similar to that shown in FIG. is idler 1
Do not apply rotational force to the rubber part 1. At the same time, the rubber part provided on the idler 11 is attached to the idler mounting piece 13.
Due to this operation, it is not in pressure contact with the reel stand 16. From this, no rotational force is applied to the reel stand 16 at all. Next, when tape loading is performed, the master gear 9 rotates counterclockwise, and the guide pin 2 is guided along the cam groove 10 from point A and moves to point B. At this time, since the cam groove 10 is provided on the outer periphery of the master gear 9 in a concentric arc shape, the guide link 1 does not rotate at all about the support shaft 4, and the pressing portion 5 always supports the pivot shaft 1 of the idler mounting piece 13. continues to apply a constant pressing force to the shaft 14. When the guide link 1 is guided to point B, the spring 8 causes the guide link 1 to rotate clockwise about the support shaft 4. This state is the state shown in FIG. At this time, the guide pin 2 is located at C of the cam groove 10.
held at a point. Therefore, the pressing portion 5 releases the pressing force on the pivot shaft 14, and the idler 11 to which the idler pin 12 is attached as a pivot becomes free. At the same time, the guide arm 15
Rotates clockwise around a pivot provided at one end,
The idler mounting piece 13 moves downward, and the pulley 18 rotates in accordance with the rotation of a motor (not shown). At this time, the rubber portion of the idler 11 comes into pressure contact with the pulley 18, and the idler mounting piece 13 rotates due to the rotation transmission of the pulley 18, so that the reel stand 16 and the idler 11 are brought into pressure contact. Therefore, the rotational force of the pulley 18 is directly transmitted to the reel stand 16. Tape loading is completed in this state. Subsequently, when changing from the loading state to the unloading state, the master gear 9 is rotated clockwise. Along with this, the guide pin 2 moves from point C to point D shown in FIG. Cam groove 1
0 has a slope between point D and point E, so the surface of master gear 9 gradually pushes up guide pin 2 in the direction away from master gear 9 surface. Since the plate spring parts 6 and 7 are elastic, the plate spring parts 6 and 7 are bent and apply pressure to the guide pin 2 in the direction of the surface of the master gear 9. At this time, by resting on the leaf springs 6 and 7, the guide pin 1 moves only in the direction perpendicular to the plane of the paper. Therefore, the direction of the tracing force is always applied in one direction, and this state is shown by the broken line in FIG. Here, when tracing from point D to point E of cam 10, guide ring 1
As the cam groove 10 is traced, the guide link 1
rotates counterclockwise, and the pressing part 5 gradually presses the pivot 14 provided on the idler mounting piece 13, pushing the idler mounting piece 13 upward in the drawing. From this, the reel stand 16 and idler 11
Simultaneously, the pressure contact between the pulley 18 and the rubber portion of the idler 11 is released. Furthermore, reel stand 16 and idler 1
The pressure contact with the rubber part 1 is completely released, the rotational force of the pulley 18 is no longer transmitted, and a constant pressing force is applied to the pivot shaft 14 provided on the idler mounting piece 13. When the guide pin 2 has finished tracing the point E of the cam groove 10, the guide pin 2 is located on the outer periphery of the master gear 9, and the guide link 1 is positioned at the cam groove 1.
It rotates counterclockwise around the support shaft 4 within a range regulated by 0. As the master gear 9 rotates clockwise, it returns from point E to point A of the cam groove 10, and the idler mounting piece 13
While continuing to press the pivot 14 of the idler 11 with a constant pressing force, press the idler pin 12 against the notch 20a provided in the guide groove 20.
The position is maintained in a state where it is separated from the reel stand 16. When the idler 11 is pressed against the reel stand 17, the motor pulley 18 rotates in the opposite direction, thereby performing the same operation as described above. (f) Coin of the invention By implementing the invention, the spring, which was conventionally provided as a separate part from the guide link, is integrated with the guide link to provide a spring portion on the opposite surface of the guide link. As a result, the cam guide mechanism, which conventionally was composed of two points, a guide link and a spring, can be composed only of the guide link, and the number of parts can be reduced. This is effective in promoting miniaturization of magnetic recording and reproducing devices. At the same time, by providing leaf spring parts on opposing surfaces of the guide link, the strength and elasticity of the guide link itself can be maintained, and the guide pin provided on the guide link can be traced only in the vertical direction relative to the master gear. It is possible to apply force and reliably trace the cam on the master gear. Furthermore, in the process of assembling the magnetic recording/reproducing apparatus, work efficiency is greatly improved by replacing the conventionally troublesome installation of a spring with a guide link provided with a plate spring portion. Needless to say, all of these effects will be extremely effective in miniaturizing 8mm videos and the currently used magnetic recording and reproducing devices.

[Brief explanation of the drawing]

FIG. 1 is a plan view of a guide arm according to an embodiment of the invention, FIG. 2 is a longitudinal sectional view of a guide arm according to an embodiment of the invention, and FIG. 3 is a plan view of a master gear.
FIGS. 4 and 5 show embodiments of the present invention. Explanation of main drawing numbers, 1 ...Guide link, 2...
Guide pin, 6, 7...plate spring part, 9 ...master gear, 10...cam, 11...idler, 1
3... Idler mounting piece, 16, 17... Reel stand, 18... Pulley, 20... Guide groove.

Claims (1)

[Scope of utility model registration request] a motor that rotates forward and backward; a concentric arc-shaped first cam groove; and the first cam groove, which is bent in the radial direction continuously from the first cam groove to form a V-shape and an inclined surface from the middle of the bend. a master gear having a second cam groove connected with a step, a guide pin that follows the first and second cam grooves at one end, a pressing portion at the other end, and a rotatable master gear; The guide link is composed of a pivotally supported guide link and an idler mounting piece on which a rotatable idler for transmitting the rotation of the motor is mounted and biased in one direction in opposition to the pressing part, and one end of the guide link. An idler drive device characterized in that the guide pin is formed in the shape of a plate spring having flexibility in the direction of the support shaft and is always in contact with a cam groove.