JPH06257621A - Clutch - Google Patents

Abstract

PURPOSE:To provide an inexpensive clutch capable of transmitting and cutting off torque by simply constituting the clutch for transmitting rotating force of a drive unit to a rotary shaft by the use of a spring. CONSTITUTION:A first and a second torque plate 1, 2 are disposed face to face in a rotary axis X, where the former is rotatable on the rotary axis X while the latter is rotated integrally with the rotary axis X. Bosses 3, 4 are disposed in a face-to-face manner on a side opposite to the torque plates 1, 2, and surrounded by a coil spring 5. A half of the coil spring 5 is fastened to the boss 4 while the remaining half thereof is loosely disposed in the boss 3. A pin 15 is pressed against the coil spring 5 by a press force applying means comprising a sleeve 10, a fork 14, and the pin 15 so as to reduce the diameter of the coil spring 5 and transmit torque.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a clutch for on / off switching of office small power equipment or for torque transmission / disconnection such as an electromagnetic clutch.

[0002]

2. Description of the Related Art An electromagnetic clutch is used for a double feed preventing mechanism of a paper feeding device such as a copying machine. This is to rotate and stop the rotary shaft by an electric signal, and has an advantage that any time can be set. However, the above copying machines do not require complicated rotation / stop patterns, and simply turn on.
-Setting the OFF time is often good.

[0003]

However, the mechanism such as the electromagnetic clutch described above is expensive in equipment, requires a power source, requires a large number of power sources, and can easily turn on / off a small power source. Cannot be used for.

According to the present invention, the clutch mechanism is constructed so that torque can be transmitted from one of the two torque plates to the other by utilizing the contracting force of the spring so as to be interrupted. The mechanism is simple and inexpensive to manufacture. It is an object to provide a versatile clutch.

[0005]

As a means for solving the above-mentioned problems, the present invention has a first torque plate rotatable with respect to a rotating shaft and a second torque plate rotating integrally with the rotating shaft facing each other. A boss portion is provided on each of the torque plates facing each other, and a coil spring extending over both boss portions is wound around the outer periphery of the boss portion, and the coil spring portion on the first torque plate side is free from the boss portion of the first torque plate. The second spring plate side coil spring portion is tightly fitted to the boss portion of the second torque plate, and a pressing force applying means for contacting the first torque plate side coil spring and applying an axial pressing force. The torque limiter is provided with.

In this case, it is preferable to interpose a contact adjusting member between the first torque plate side end of the coil spring and the pressing force applying means.

The contact adjusting member may be formed of a pressing plate having a recess whose cross section has an inclination angle, a corrugated plate elastically transmitting a pressing force, and a washer.

Further, the end of the coil spring on the side of the second torque plate may be fixed to the second torque plate, and a plate having the same shape as the gap may be inserted and fixed in the gap between the coil spring and the second torque plate. Good.

In any of the above cases, the pressing force applying means is rotatably fitted to a boss portion projecting to the other end of the first torque plate, a fork for moving the sleeve in the axial direction, The torque plate and the sleeve may be configured by a pin inserted into a hole that penetrates the sleeve in the axial direction.

[0010]

According to the clutch of the present invention configured as described above, the rotational torque can be transmitted from the first torque plate to the second torque plate or the opposite direction. In the state where the axial pressing force is not applied to the coil spring by the pressing force applying means, the first torque plate is cut off from the second torque plate, and the torque is not transmitted.

When the pressing force applying means is driven to apply a pressing force to the coil spring, the pressing force applying means applies a torsional force to the coil spring at a portion where the pressing force applying means contacts the coil spring. When this torsional force acts in a direction to reduce the diameter of the coil spring, the diameter of the coil spring is reduced and fixed to the boss portion of the first torque plate, and at the same time, the other half of the coil spring is given a rotational force. The second torque plate rotates together with the rotary shaft, and torque is transmitted. When the pressing force of the pressing force applying means is released,
The coil spring expands in diameter and is disengaged from the first torque plate to cut off torque transmission.

In the second invention, the contact adjusting member is interposed between the coil spring and the pressing force applying means. This is because when the external force such as the centrifugal force or the pressing force of the pressing force applying means acts on the coil spring, the end of the coil spring on the first torque plate side is deformed and the abutting position is displaced. Is effective in preventing the coil spring from normally contacting the coil spring and the diameter of the coil spring not being reduced when required. Therefore, this ensures the engagement of the clutch even during rotation.

A third aspect of the invention is realized by means that embodies the contact adjusting member of the second aspect of the invention. The force of the pressing force applying means can be reliably transmitted by the means of such a configuration.

In the fourth aspect of the invention, the end of the coil spring on the second torque plate side is securely fixed by inserting the gap member.

A fifth aspect of the invention embodies the pressing force applying means used for any of the above aspects,
By moving the sleeve with a fork, the pin inserted into the through hole is moved to apply a pressing force to the coil spring.

[0016]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a main sectional view of the clutch of the embodiment. Reference numeral 1 is a first torque plate having a gear 1a engraved on the outer periphery thereof, and power is transmitted to the first torque plate 1 via a pinion (not shown) that engages with the gear 1a, for example. The first torque plate 1 is rotatably provided with respect to the rotation axis X.

Reference numeral 2 is a second torque plate provided so as to face the first torque plate 1. First torque plate 1 and second torque plate 2
Have boss portions 3 and 4 on the surface sides facing each other, and their outer diameters are substantially the same. A coil spring 5 is provided on the outer periphery of both of the boss portions 3 and 4 so as to straddle both of them.

One half portion 5b of the coil spring 5 is fitted into the boss portion 3 with a slight clearance, and the other half portion 5a is tightly fitted to the boss portion 4.

The second torque plate 2 is integrally fixed to the rotary shaft X with respect to rotation by a pin 7 which engages with a key groove 6 provided in the inner diameter thereof. 8 is a retaining ring.

Another protruding boss portion 9 is provided at the opposite end of the first torque plate 1, and a sleeve 10 as a holding member is rotatably and slidably fitted on the outer periphery of the boss portion 9. A C-shaped ring 12 is fitted in the groove 11 in the boss portion 9, and the position of the sleeve 10 is determined by positioning the ring 12 in either of the two grooves 13 having a semicircular cross section provided in the inner diameter of the sleeve 10. Hold in position.

The sleeve 10 has a U-shaped cross section as shown in the drawing, and a fork 14 as a lateral pressing member used to apply a pressing force in the lateral direction is freely contactable and separable in this groove. Mated. A plurality of pins 15 (three pins in this embodiment as shown in FIG. 3) are inserted into the sleeve 10 at appropriate pitches through holes penetrating in the axial direction of the rotary shaft X.

The pin 15 is inserted into a hole penetrating the first torque plate 1 at the same pitch as that of the sleeve 10, and the tip of the pin 15 is moved to the position of the sleeve 10 so that the pin 15 can come into contact with the end of the coil spring 5. It is provided in. Sleeve 10
A ring spring 16 is secured to the outer surface of the pin with a plurality of screws 17 (or rivets) provided at an appropriate pitch so as to press the head of the pin 15.

FIG. 2 shows an example of the coil spring 5, and the half portions 5a and 5b are formed coaxially as shown.

FIG. 3 is a detailed perspective view of the ring spring 16. The ring spring 16 acts as a spring by shifting the positions of the pin 15 and the screw 17.

The torque transmission is interrupted / transmitted in the following manner by the clutch of the embodiment constructed as described above.

The state shown in FIG. 1 shows the state in which the clutch is disengaged. Even if the external torque is transmitted to the gear 1a and the first torque plate 1 is rotated, the coil spring 5 is not engaged with the boss portion 3 of the first torque plate 1. Therefore, the sleeve 10 is simply rotated by the pin 15. Yes, no power is transmitted to the rotation axis X.

In this case, the sleeve 10 is held at the position shown by the ring 12 fitted in one of the grooves 13, and the fork 14 is in the state of a chain line so as not to touch the groove of the sleeve 10. Alternatively, the forks 14 are pulled apart and held in another position.

Next, when the fork 14 is moved in the axial direction of the rotary shaft X to move the sleeve 10 to the coil spring 5 side, one groove 13 of the sleeve inner diameter to the other groove 13 is formed.
The herring 12 is reduced in diameter and fitted into the other groove 13 of the herring 12, and is stabilized at that position.

In this state, the pin 15 presses the coil spring 5 in the axial direction. Since the coil spring 5 is not engaged with the boss portion 3 until the pressing force by the pin 15 is applied, the second torque plate 2 is still stopped,
The coil spring 5 is also not rotating. Therefore, when the rotating pin 15 is pressed against the coil spring 5, the pin 15 frictionally engages with the coil spring 5, and the tangential force due to the contact load of the pin 15 on the coil spring 5 and the friction coefficient at that portion. Acts as a screw force.

In this case, for example, if the coil spring 5 is left-handed as shown in FIG. 2, if the direction of the twisting force by the pin 15 is in the opposite direction to the coil spring 5, the coil spring 5 contracts in the same direction. If so, increase the diameter. This is because when the above-mentioned torsional force is transmitted from the half portion 5b of the coil spring 5 to the other half portion 5a, the half portion 5a is stationary and thus resists rotation, and thus the half portion of the coil spring 5 is prevented. This is because when one end of 5b is twisted in the same direction, the diameter is increased, and in the opposite direction, the diameter is reduced.

When the diameter of the one half portion 5b of the coil spring 5 is reduced, the inner diameter of the coil spring 5 engages with the boss portion 3, so that the boss portion 3, the coil spring 5 and the boss portion 4 rotate together to form a spring. A type clutch is constructed so that the torque of the first torque plate 1 is transmitted to the second torque plate 2 and the rotary shaft X integral with this is rotated (FIG. 4).

When the rotating direction of the pin 15 is the same as the winding direction of the coil spring 5, if the diameter of one half portion 5b increases,
The other half portion 5a also tends to expand in diameter due to the influence, and the interference fit with the boss portion 4 is loosened, so that torque cannot be transmitted. Therefore, this clutch is established only when the rotation of the first torque plate 1 is opposite to the winding direction of the coil spring 5.

When releasing the clutch function, the sleeve 10 is moved by the fork 14 in the direction in which it is separated from the first torque plate 1, and the coil spring 5 naturally expands in diameter because the axial pressing force is lost. The torque transmission is cut off.

Although the pressing force of the fork is transmitted to the coil spring 5 through the pin 15 in the above-described embodiment, for example, a disk plate that abuts the coil spring 5 is provided, and the protrusion is formed integrally with the sleeve. It is obvious that the mechanism for applying a pressing force in the axial direction to the coil spring 5 such as pressing the disk plate can be modified in various ways other than the above, and it goes without saying that the present invention includes any of them.

FIG. 5 shows an example in which a pin contact adjusting member is interposed between the coil spring 5 and the pin 15. Reference numeral 18 is a push plate, 19 is a wave washer, and 20 is a washer member. As shown in the figure, the push plate 18 is formed of a disc having a conical recess whose cross section has an inclination angle, and the corrugated washer 19 elastically pushes the pin 15 from the pin 15 to the coil spring 5 via the push plate 18. introduce. The washer 20 is a flat plate having a diameter larger than the set radius of the pin 15 and is provided to surely transmit the pressing force of the pin 15.

By the contact adjusting member, the pressing force is surely transmitted to the coil spring 5, and the function as the clutch can be surely maintained even when the centrifugal force acts during the rotation.

In this embodiment, the end of the coil spring 5 on the second torque plate side is further formed with a hook 5h as shown in the enlarged portion of the circle A, which is formed on the side wall of the second torque plate. A gap member 5s, which is fitted and fixed in the small hole 5i and has the same shape as this gap, is inserted in the gap between the end of the coil spring 5 and the side wall to prevent the coil spring from twisting.

In principle, the other constituent members are the same as those in the first embodiment except the above-mentioned portions, and the description thereof will be omitted.

[0040]

As described above in detail, in the clutch of the first invention, the coil spring is interposed between the first torque plate and the second torque plate, and the coil spring is pressed in the axial direction by the pressing force applying means. Since the coil spring is reduced in diameter to transmit torque, and the coil spring is disengaged when the pressing force is released, an inexpensive clutch that freely transmits and disconnects torque by a simple mechanism using the coil spring can be obtained. There is an advantage.

In the second invention in which the contact adjusting member is interposed between the coil spring and the pressing force applying means, on the premise of the effect of the first invention, the pressing force applying means is further acted by centrifugal force during rotation. The effect that the pressing force is reliably transmitted to the coil spring is obtained.

In the third aspect of the invention, the contact adjusting member is embodied by the pressing plate, the corrugated plate, and the seat plate, and the pressing force is reliably transmitted.

In the fourth aspect of the invention, the gap member is inserted into the end of the coil spring on the side of the second torque plate to securely fix the coil spring and prevent the action of the coil spring from being hindered.

In a fifth aspect of the present invention, the pressing force applying means is embodied by the structure of a fork, a sleeve and a pin, and in any of the above inventions, the pressing force applying means smoothly and reliably transmits the pressing force. it can.

[Brief description of drawings]

FIG. 1 is a main sectional view of a clutch according to an embodiment.

FIG. 2 is an example of a coil spring

[Fig. 3] Detailed view of a ring for pin pressing.

[Fig. 4] Operation explanatory diagram

FIG. 5 is a main sectional view of a clutch according to a second embodiment.

[Explanation of symbols]

 1 1st torque plate 2 2nd torque plate 3 boss part 4 boss part 5 coil spring 9 boss part 10 sleeve 14 fork 15 pin 18 push plate 19 corrugated washer 20 washer

Claims (5)

[Claims] 1. A first torque plate rotatable with respect to a rotating shaft and a second torque plate rotating integrally with the rotating shaft are provided so as to face each other, and boss portions are provided on opposite sides of the respective torque plates. A coil spring that extends over both bosses is wound around the outer periphery of the coil spring.The coil spring portion on the first torque plate side is loosely fitted to the boss portion of the first torque plate, and the coil spring portion on the second torque plate side is (2) A clutch having a boss portion of a two-torque plate that is press-fitted and is provided with a pressing force applying means that abuts a coil spring on the first torque plate side to apply an axial pressing force. 2. The clutch according to claim 1, wherein a contact adjusting member is interposed between the first torque plate side end of the coil spring and the pressing force applying means. 3. The contact adjusting member is formed of a pressing plate having a recess whose cross section has an inclined angle, a corrugated plate elastically transmitting a pressing force, and a washer.
The clutch described in. 4. The second torque plate side end of the coil spring is fixed to the second torque plate, and a member having the same shape as the gap shape is inserted and fixed in the gap between the coil spring and the second torque plate. The clutch according to any one of claims 1 to 3. 5. A sleeve in which the pressing force applying means is rotatably fitted to a boss portion protruding to the other end of the first torque plate, and a fork for moving the sleeve in the axial direction.
The first torque plate and a pin that is inserted into a hole that penetrates the sleeve in the axial direction.
The clutch according to any one of 1 to 4.