JPS58200845A - Rotational-power transmission device - Google Patents

Abstract

PURPOSE:To obtain a simply-constructed transmission device with reduced number of parts and little torque loss during the rotation of a rotationally-driven body such as a magnetic-tape reel disk in a device to rotate a motor regularly and reversely to rotate the rotationally-driven body. CONSTITUTION:A main revolution body 3 is pushed onto a motor shaft 4 of a motor 1 fast fixed on a base plate 2 to be regularly and reversely rotated, while the first and the second rotational bodies 6 and 8 are fitted via the first and the second one-directional clutch mechanisms 5 and 7 to make a ''contact'' state when each motor shaft 4 is rotated regularly and reversely. Furthermore, the motor shaft 4 is loosely fitted with a rotational member 9. It supports a rotation-transmission member 11 by a shaft 10 to be rotatable on its one end, and an arm 20 with the first and the second catching parts 20a and 20b by a shaft 19 on its other end. The rotational member 9 is automatically oscillated in accordance with the regular and reverse rotation of the motor 1, and the rotation-transmission member 11 is selectively brought in contact with a reel disk 15 or 16.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention is applicable to devices such as tape recorders that rotate a driven body, such as a take-up reel stand, by rotating a motor in forward and reverse directions, thereby winding the entire magnetic tape. The present invention relates to a rotary power transmission device useful for use.

In conventional rotary power transmission devices of this kind, for example, systems that utilize combinations of friction plates and springs, permanent magnets and hysteresis paulownia wood, while the rotating driven objects are being driven simultaneously, torque loss due to the friction plates and hysteresis particles occurs. Due to the structure, it was not possible to eliminate this torque loss. For this reason, the drive motor requires more torque than necessary (torque loss), and a large amount of motor current has to be passed.

The present invention solves the above-mentioned conventional problems, has a structure in which almost no torque loss occurs while rotating the rotationally driven body, has a small number of components, has a simple component configuration, and transfers the power of the motor to the motor. It is an object of the present invention to provide a co-rotating power transmission device that can reliably transmit power to a desired rotationally driven body according to the rotational direction.

Hereinafter, the present invention will be explained using an example of a video tape recorder.

1 and 2 are plan views of essential parts in various states of an embodiment of the present invention, and FIG. 3 is a sectional view of the essential parts. In those drawings, a motor capable of forward and reverse rotation is fixed to a substrate 2. The main rotating body 3 is press-fitted into the motor shaft 4 and rotates integrally with the motor shaft 4. The first one-way clutch mechanism 5 is fitted onto the motor shaft 4, and the first
It is fixed to the rotating body 6 of. When the motor shaft 4 rotates in the forward direction (hereinafter referred to as clockwise direction), the first rotating body 6 is rotated clockwise by 1"11" by the first unidirectional clutch mechanism 5.
However, when the motor shaft 4 rotates in the opposite direction (hereinafter referred to as counterclockwise), the first rotating body 6 does not receive the rotational force of the motor shaft 4 due to the first unidirectional clutch mechanism 6, so that the first rotating body 6 does not rotate. do not. The second one-way clutch mechanism 7 is fitted onto the motor shaft 4 and fixed to the second rotating body 8 . When the motor shaft 4 is rotating counterclockwise, the second one-way clutch mechanism 7 causes the second rotating body 8 to rotate counterclockwise, but the motor shaft 4 is rotating clockwise. Sometimes by the second one-way clutch mechanism 7,
Since the second rotating body 8 is not subjected to the rotational force of the motor shaft 4, it does not rotate completely. The rotary member 9 is rotatably loosely fitted onto the motor shaft 4, and a rotation transmitting member 11 is rotatably provided on the shaft 1o implanted at the negative end thereof. A coiled spring 14 is stretched between a convex portion 12 provided on a part of the rotating portion 9 and a convex portion 13 provided on the substrate 2. The first reel stand 16 and the second reel stand 1 (which are rotationally driven bodies)
The shafts 17 and 1B are rotatably mounted on the substrate 2, respectively. When the rotating member 9 rotates to the position shown in FIG. 1 or FIG. Reel stand 15 or second reel stand 1
The rotational driving force of the motor shaft 4 is transmitted to the first reel stand 15/ζ to the second reel stand 16. An arm 2° is rotatably provided on a shaft 19 provided at the other end of the rotating member. The first locking portion 20a and the second locking portion 20b provided on the arm 2o engage with or separate from the convex portions 21, 22VC of the first rotating body 6 and the second rotating body 8, respectively.

Arm 20, first locking part 20a, second locking part 20
b, the shaft 19, and the protrusions 21 and 22 constitute an engaging means.

Shafts 23 and 24 are implanted in the base plate 2, and the rotating part 9
When moving from the position shown in FIG. 1 to the position shown in FIG. The engagement with the portion 21 is released, and the arm 2o rotates to a position where the second locking portion 20b and the convex portion 22 engage. When the rotating member 9 moves from the position shown in FIG. 2 to the position shown in FIG.
o comes into contact with the shaft 23 and the rotating member 9 moves further, the engagement between the second locking part 20b and the convex part 22 is released, and the first locking part 2oa and the convex part 21 The arm 2o is rotated to a position where it is engaged. The shafts 23 and 24 and the spring 14 constitute release means.

Next, the operation of this embodiment will be explained step by step.

In FIGS. 1 and 3, when the motor shaft 4 rotates clockwise, the main rotating body 3 also rotates clockwise, and the first rotating body 6 is also rotated clockwise by the first unidirectional clutch mechanism 5. However, the second rotating body 8 is not rotated by the second one-way clutch mechanism 7.

When the first rotating body 6 rotates clockwise, the convex portion 21 and the first locking portion 20a engage with each other, and since the arm 2o is on the cooperating member 9, the rotating portion 9 is rotated. Motor Il! 1lI4
It receives a clockwise rotational force due to the rotational force of , and begins to move clockwise. At this time, the rotating member 9 is receiving a counterclockwise rotational force due to the elastic force of the spring 14. Rotating member 9
overcomes this elastic force and rotates clockwise, and the protrusion 12 provided on the rotating member 9 is positioned to the right of the straight line connecting the motor tIII4 and the protrusion 13 provided on the board 2. At this time, due to the elastic force of the spring 14, the rotating member 9 receives a clockwise rotating force around the entire center of the motor shaft 4. As the rotating part +A9 further moves 1411 clockwise, arm 2° comes into contact with 4Ql+ 24, and as it rotates further, the clockwise offshore movement is regulated by Arno, 2O7d and 24. Therefore, as shown in FIG.
The arm 2o moves to a position where it engages with the lls 22. Due to the elastic force of the spring 14, the rotation transmission member 11 is pressed against the first reel stand 15, and the rotational driving force' of the motor shaft 4 is transferred to the main rotary body 3 and the rotation transmission member 11 to the first reel stand 1-. 15, and rotates the first reel stand 16K clockwise. At this time, motor 1&' is the first reel stand 1.
No loss torque was generated except when 5 was rotated 1[]1.

In FIGS. 2 and 3, when the motor shaft 4 rotates counterclockwise, the main rotating body 3 also rotates counterclockwise, and the second rotating body 8 also rotates due to the second one-way clutch temporary structure 7. Although it rotates counterclockwise, it does not rotate due to the first one-way clutch mechanism 5 of the first rotating body 611-i. When the second rotating body 8 rotates counterclockwise, the convex portion 22 and the second locking portion 20
b are engaged and the arm 20 is on the rotating member 9, so
The rotating member 9 receives a counterclockwise rotational force due to the rotational force of the motor shaft 40, and begins to rotate counterclockwise. At this time, the rotating member 9 is receiving a clockwise rotating force due to the elastic force of the spring 14. The rotating member 9 overcomes this elastic force and rotates counterclockwise, and the protrusion 12 provided on the rotating member 9 connects the motor shaft 4 and the protrusion 13 provided on the base plate 2. When located on the left side of the straight line, the rotating member 9 receives a counterclockwise rotating force about the motor shaft 4 due to the elastic force of the spring 14. As the rotating member 9 further rotates counterclockwise,
When the arm 20 comes into contact with the shaft 23 and rotates further, the arm 20 is restricted from rotating counterclockwise by ll1lII23, so as shown in FIG. The engagement with the portion 22 is disengaged, and the first locking portion 20
The arm 2o moves to a position where a and the protrusion 21 engage with each other. Due to the elastic force of the spring 14, the rotation transmission member 11 is
The rotational driving force of the motor shaft 4 is transmitted to the second reel stand 16I through the main rotator 3 and the rotation transmission member 11, and the second reel stand 16 is rotated counterclockwise. Drive to rotate. At this time, the motor 1 is connected to the second reel stand 1.
No loss torque is generated except for rotationally driving 6.

As is clear from the above description, the present invention not only rotates and moves a desired rotated driven body according to the rotational direction of the motor, but also causes torque loss during co-rotation of the rotated driven body. This makes it possible to save power, make the motor smaller, and lower costs. Sara V, simple message.
Because it is a mechanism, it can reduce the number of component parts and has many excellent effects such as improved operational reliability.

[Brief explanation of the drawing]

FIGS. 1 and 2 are plan views of essential parts of each track V according to an embodiment of the present invention, and FIG. 3 is a sectional view of the mounting portion of the same embodiment. 1...Motor, 2...Board, 3...
...Main rotating body, 4...Motor shaft, 6...
・First unidirectional clutch mechanism, 6...first rotating body, 7...second unidirectional clutch mechanism,
8... Second rotating body, 9... Rotating member, 11... Rotation transmission member, 12... Convex) 911.13... ... Convex portion, 14 ... Spring, 15 ... First reel stand, 16 ...
・Second reel stand, 20...Arm, 20a・
...first locking part, 20b...second locking part, 21.22...convex part. Name of agent: Patent attorney Toshio Nakao and 1 other person No. 1
Figure 2

Claims (1)

[Scope of Claims] First and second rotationally driven bodies;
iE-inverse 1 arranged approximately equidistantly from the rotationally driven body of
! ! a main rotating body capable of shifting, first and second one-way clutch mechanisms, and when the main rotating body makes a small rotation, the first one-way clutch mechanism [)1fi: L-to rotating body a first rotating body rotating in the same direction as +MI a[2-
The second one-way clutch device 114 rotates the I! ! +612'' h of the second rotary body rotating in the same direction as the rotary body and the first and second co-rotated driven bodies.
When the main rotating body rotates IF, the first
A transmission unit 7 transmits the rotational force of the rotating body to the rotationally driven body.
, a rotation transmitting section (") that transmits the same rotational force of the main rotating body to the second rotationally driven body when the rotating body rotates in the reverse direction;
) [I: A rotary member which is provided so as to be movable together about the rotational axis of the main rotary body and which rotatably maintains the one-eye, one-rotation transmission portion support, and which is provided on the rotary member. When the retaining means engages and disengages the first and second rotating bodies, and the rotation transmitting member comes into contact with the rotationally driven body of the first and second rotary bodies, the first rotating body When the engagement between the body and the engaging means is released and the rotation transmitting member abuts the second rotationally driven body, the engagement between the second rotary body and the engaging means is stopped. A rotary power transmission device comprising a release means for releasing the rotation power.