JPH0212332Y2 - - Google Patents

Description

[Detailed description of the invention] The present invention relates to a rotation transmission device that transmits rotation from an operating shaft to a driven shaft, and can effectively suppress breakage and damage to parts especially when an overload is applied to the driven shaft. This invention relates to improvements in rotation transmission devices.

FIG. 1 shows a conventional rotation transmission device, in which a casing 2 is attached to a wall 1 of the device, and within this casing 2, an operating shaft 3 and a driven shaft 4 are coaxially connected. In this connection, friction plates 5 and 6 are attached to each tip of the operating shaft 3 and driven shaft 4, the friction surfaces of these friction plates 5 and 6 abut each other, and a compression spring 7 is attached to the shaft body of the operating shaft 3. This is done by extrapolating and biasing the friction plate 5 in the direction of the friction plate 6 of the driven shaft 4. In the rotational force transmission device having such a structure, rotation is transmitted from the operating shaft 3 to the driven shaft 4 by the frictional force between the friction plates 5 and 6, and at the same time, rotation is transmitted from the operating shaft 3 to the driven shaft 4 due to an equipment failure or the like. In this case, the overload causes a slip between the friction plates 5 and 6, blocking the rotation and preventing damage to the motor, gears, and other parts attached to the operating shaft 3. There is. However, in devices that utilize such frictional force, the frictional force varies greatly depending on the condition of the frictional surface of the friction plate, the lubrication state, etc., so the slip torque varies and it is not possible to stably interrupt rotation. This had the disadvantage that the slip torque fluctuated during use due to wear of the friction surface, etc.

The present invention utilizes the fact that the friction force of the coil spring changes by reducing or enlarging the diameter of the coil spring to effectively transmit and interrupt rotation, thereby eliminating the above-mentioned drawbacks of the conventional method. a driven shaft having a cylindrical connecting end formed therein; an actuating shaft having an engaging protrusion at an end housed in the connecting end and coaxially attached to the driven shaft; a coupling ring disposed between the operating shaft and having an engaging protrusion formed at the end on the operating shaft side; a torsion plate attached between the operating shaft and the coupling; and a torsion plate at both ends. The hook portion is inserted between the actuating shaft and the engaging protrusion of the coupling end, and the coil portion includes a spring housed in pressure contact with the inner wall of the connecting end, and the coil portion is configured to reduce the frictional force of the spring to the driven shaft. It is characterized by transmitting and blocking rotation by increasing and decreasing it.

Hereinafter, one embodiment of the present invention will be described in detail with reference to FIGS. 2 and 3.

In these figures, a wall 11 of the device is fitted with a casing 17, in which a rotation transmission device is housed. This rotation transmission device includes an operating shaft 12 and a driven shaft 13 that are coaxially attached, a coupling 14 provided between the operating shaft 12 and the driven shaft 13, and a coupling 14 provided between the operating shaft 12 and the driven shaft 13.
4 and the operating shaft 12, and a spring 16 for generating frictional force. The driven shaft 13 has a cylindrical connecting end 13a attached to the casing 17 formed on the operating shaft 12 side, and the coupling end 14 and the spring 16 are housed in the connecting end 13a. The operating shaft 12 that transmits the rotation of a motor or the like (not shown) to the driven shaft 13 has a large-diameter ring 12a attached to the inside of the casing 17, and the ring 12a
A circular arc-shaped engagement protrusion 12b as shown in FIG. 3 protrudes from the tip toward the driven shaft 13 side. Next, the coupling ring 14 is disposed between the operating shaft 12 and the driven shaft 13, and the coupling end 1
3a, and an arcuate engaging protrusion 14a as shown in FIG. 3 protrudes from the operating shaft 12 side. Further, this coupling 14 is connected to the operating shaft 12.
are connected to each other by a plate-shaped torsion plate 15, and the rotation of the actuating shaft 12 is transmitted through the torsion plate 15. Further, the spring 16 is a coil spring,
It is housed in the connecting end 13a of the driven shaft 13, and its coil portion 16a is connected to both the engaging protrusions 12.
a and 14a, but the hook portions 16 at both ends
As shown in FIG. 3, the engagement protrusions 12b and 16c are erected on the side of the coil portion and inserted into the center portions of the engagement protrusions 12b and 14a. This spring 16 comes into contact with the inner wall of the connecting end 13a of the driven shaft 13 and applies a frictional force to the end 13a. Therefore, the coil portion 16a is attached in a press-contact state within the connecting end 13a. There is.

Note that the engaging protrusions 12b and 14a of the actuating shaft 12 and the coupling ring 14 are not limited to arcuate shapes, but may be mere protrusions as long as they engage with the hook portions 16b, 16c of the spring 16, as will be described later. .

Next, the operation of transmitting and interrupting rotation in the rotation transmitting device configured as described above will be explained.

In FIG. 3, when the operating shaft 12 rotates counterclockwise as indicated by arrow A, this rotation is transmitted to the coupling 14 via the torsion plate 15, causing the coupling 14 to rotate. The engagement protrusion 14a of the rotary coupling 14 comes into contact with the hook portion 16c of the spring 16 on the driven shaft 13 side, thereby enlarging the diameter of the spring 16. With this diameter expansion, the spring 16 is
The driven shaft 13 rotates in the same direction as the driven shaft 13 comes into contact with the inner wall of the connecting end 13a of No. 3 and its frictional force increases. When rotation is being transmitted in this manner, if an overload is applied to the driven shaft 13 due to equipment failure, for example, and the driven shaft 13 locks, the coupling 1
4 also stops rotating, the torsion plate 15 is deflected by the rotational force of the operating shaft 12, and when this deflection becomes large, the engagement protrusion 12b of the operating shaft 12 is bent by the spring 1.
6 on the operating shaft 12 side,
Press the hook in the direction of arrow A. Since this pressing direction is a direction in which the spring diameter is reduced, the frictional force generated between the spring 16 and the inner wall of the connecting end 13a of the driven shaft 13 is reduced, and the spring 16 slips and idles within the end 13a. Transmission of rotation to the driven shaft 13 is cut off.

The above is the same when the operating shaft 12 rotates in the clockwise direction indicated by the arrow B, and by blocking these rotations, no overload is applied to the operating shaft 12, which prevents damage to the motor, etc. can be prevented. In addition, in the present invention, the driven shaft 13 can be connected to a motor or the like to transmit rotation from the driven shaft 13 to the operating shaft 12, and the same operation can be achieved.

Therefore, according to the present invention explained above, when an overload is applied to the driven shaft, accurate shutoff can be performed, and stable rotation transmission and shutoff can be achieved without fluctuations in torque during use. It has the effect that it can be done.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view of a conventional example, FIG. 2 is a cross-sectional view of an embodiment of the present invention, and FIG. 3 is a cross-sectional view taken along the - line. 12... Operating shaft, 12b... Engaging protrusion, 13...
... Driven shaft, 13a ... Connection end, 14 ... Coupling, 14a ... Engaging protrusion, 15 ... Torsion plate, 16 ... Spring.

Claims (1)

[Scope of utility model registration request] a driven shaft having a cylindrical connecting end formed therein; an actuating shaft having an end coupling protrusion housed in the connecting end and coaxially attached to the driven shaft; and the driven shaft and the actuating shaft. a torsion plate installed between the actuation shaft and the coupling; The spring is inserted between the actuating shaft and the engaging protrusion of the coupling end, and the coil portion is housed in pressure contact with the inner wall of the connecting end, and rotation is controlled by increasing or decreasing the frictional force of the spring on the driven shaft. A rotation transmission device characterized by performing transmission and cutoff.