JPH0326287B2 - - Google Patents

Description

Detailed Description of the Invention "Field of Industrial Application" The present invention provides a torque transmitter that is provided in the middle of a rotation transmission mechanism, and that cuts off torque transmission from the input side to the output side when the transmitted torque exceeds an allowable limit. This invention relates to an overload prevention device.

"Prior Art" and "Problems to be Solved by the Invention" There are many known examples of conventional torque overload prevention devices, and their typical structures can be categorized as having a compression coil spring as the main part; A mechanical structure using a coil spring that uses the contact force of a compression coil spring to transmit torque to the passive side, or a hydraulic structure that uses hydraulic pressure to transmit rotational force and interrupts torque exceeding the allowable limit. There is something.

However, the conventionally structured torque overload prevention devices described above have the common drawback of being complicated and large in size, and although they are adaptable for use in large mechanical devices, they are not suitable for ultra-compact power transmission devices. It has the disadvantage of being less adaptable for mini power plants.

It is an object of the present invention to provide a novel torque overload prevention device that overcomes the drawbacks of the prior art described above.

"Means for Solving the Problems" The present invention that achieves the above objects is configured as follows.

That is, with reference to FIG. 1 showing the basic concept of the present invention, the torque overload prevention device of the present invention is described as follows. In the rotation transmission mechanism, friction plates 3 fixed to the rotation shaft 1 are provided at key points of the rotation shaft 1, and an annular protrusion 4 is provided between the friction plate 3 and the rotation body 2.
is fitted into the recess 5 of the rotating body 2 in a wedge shape, and an elastic intermediary body 6 which makes elastic surface contact with the friction plate 3 is clamped in a compressed manner. The friction plate 3 and the rotary body 2 are rotated together, and a slip is generated between the friction plate 3 and the elastic intervening body 6 when the torque exceeds the allowable torque.

In addition, 8 in the figure is a fixing screw of the friction plate 3,
When the fixing screw 8 is tightened, the elastic intervening body 6 is compressed and clamped between the receiving plate 7 and the friction plate 3 provided on the rotating shaft 1.

"Function" The torque overload prevention device of the present invention having the above-mentioned configuration has an elastic interposition interposed in a compressed manner between the friction plate 3 fixed to the rotating shaft 1 on the input side and the rotating body 2 on the output side. One side of the body 6 is in elastic surface contact with the friction plate 3, and the annular projection 4 on the other side is elastically fitted into the recess 5 of the rotating body 2, so that the annular projection 4 is pushed into the recess by elastic energy based on compression. The rotating body 2 and the elastic intervening body 6 form a substantially integrated rotating body, and the torque of the friction plate 3 is transmitted through the elastic intervening body 6 by slipping. The signal is smoothly transmitted to the rotating body 2 without any interference.

If the coefficient of friction between the rotating plate 3 and the elastic intermediary body 6 is selected arbitrarily, when the torque reaches the permissible limit, a slip will occur between the two and the torque to the elastic interposition body 6 will increase. Transmission is cut off and has the effect of preventing torque overload. Then, when the torque is restored to within the allowable limit again, the torque transmission described above is carried out steadily, and the torque overload prevention of the rotation transmission mechanism can function smoothly.

Since the above-mentioned effects can be achieved by simply combining the friction plate 3 with the elastic intervening body 6 and the rotating body 2, which are formed separately, the torque overload prevention device is extremely simple and compact. There are advantages.

"Example" Hereinafter, a detailed explanation will be given with reference to an example. Referring to FIG. 2, which shows one embodiment of the invention, the figure shows an ultra-compact torque overload prevention device installed in the rotation transmission mechanism of an electric window opening/closing device, and the drive shaft 11 directly connected to the electric motor is input to the device. The output shaft of the speed reducer 12 becomes the input shaft 1 of the torque overload prevention device, and a friction plate is attached to the boss 10 fixed to the input shaft 1. 3 is attached, and an elastic intermediary body 6 made of rubber is compressed and compressed between the rotating body 2 and the friction plate 3 on the output side, and the elastic interposition body 6 and the friction plate 3 are in elastic surface contact. At the same time, the annular protrusion 4 of the elastic intervening body 6 has a wedge-shaped cross section and is fitted into the recess 5 of the rotating body 2 in an elastic manner.

A presser plate 9 is provided at the upper end of the rotating shaft 1, and when the set screw 8 is tightened, an elastic intervening body 6 is compressed and clamped between the presser plate 9 and the friction plate 3. .

The detailed specifications of this embodiment are as follows.

●Elastic intermediary body 6: Chloroprene rubber, hardness 80, diameter D = 12 wear, total height H = 6.0
Wear, thickness T = 0.6 wear ●Friction plate 3: Galvanized steel plate, 0.6 wear thickness The torque overload prevention device of this embodiment with the above configuration accurately transmits small torques of 1 Kg-cm to 2 Kg-cm. At the same time, when the torque exceeds a predetermined permissible limit, the torque transmission is cut off and the above-described effect of the present invention is performed, and the window can be opened and closed (90 reciprocating strokes) more than 20,000 times.

``Effects of the Invention'' As explained above, the torque overload prevention device of the present invention includes a friction plate 3 fixed to the input shaft and an elastic force compressed between the friction plate 3 and the rotating body 2 on the output side. Since it is characterized by a simple structure in combination with the intervening body 6, it has the advantage of being able to be mechanically miniaturized, allowing the torque overload prevention device of general machinery to be made compact and compact, and also making it possible to This has the effect of making it possible to prevent torque overload in a small transmission device.

Moreover, since it has a unique and simple configuration, assembly, torque adjustment, maintenance and inspection, etc. are simple, and there is a practical advantage that manufacturing and daily management of the device are simple.

[Brief explanation of the drawing]

Fig. 1: A front view showing the basic concept of the torque overload prevention device of the present invention, Fig. 2: Showing the torque overload prevention device of one embodiment of the present invention, A is a front view thereof, B
C is a front sectional view of the elastic intervening body, and C is a plan view of the elastic intervening body. Main symbols: 1: input shaft, 2: rotating body, 3: friction plate, 4: annular projection, 5: recess, 6: elastic intervening body, 12: deceleration section.

Claims (1)

[Claims] 1. In a rotation transmission mechanism that transmits rotation to an output side rotating body having a rotation center on the axis of an input shaft,
between a friction plate fixed to the input shaft and the rotating body,
An elastic intervening body is interposed in a compressed manner and combined, and the friction plate and the elastic intervening body are in elastic surface contact, and the annular protrusion provided on the elastic intervening body is in contact with the rotating body. The friction plate and the rotating body are wedge-shaped and elastically fitted into the recess, and the friction plate and the rotating body rotate together through the elastic intervening body, and when the torque exceeds a permissible limit, the friction plate and the elastic intervening body A torque overload prevention device characterized by a structure that generates slip and interrupts torque transmission.