JPH0643361U - Torque limiter - Google Patents

Abstract

(57) [Abstract] [Purpose] To provide a torque limiter that has a large torque capacity per predetermined size, a stable set torque, and that does not require oil supply or component replacement at each operation. When the shaft member 11 and the tubular member 12 are loaded with a load equal to or more than a predetermined value during use and the positions of the shaft member 11 and the tubular member 12 around the axes change, the axial members together with the tubular member 12 rotate around the axes. Rotate. At this time, the second clutch member 2
6 and the first clutch member 25 slip, and the second clutch member 26 becomes the pressing member 23 and the shaft member 1.
It rotates around the axis together with 1, and the dog clutch 27 is brought into a meshed state. Then, the first clutch member 25 does not press the friction plate 14, the frictional coupling between the shaft member 11 and the tubular member 12 is released, and the torque is not transmitted.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 This invention relates to a torque limiter that does not require replacement of parts or replenishment of oil when returning.

[0002]

[Prior art]

 Conventionally, as a torque limiter, as shown in FIG. 7, an inner peripheral surface of a cylindrical member 2 is fitted on an outer peripheral surface of a shaft member 1 and pressure oil is supplied to a hydraulic passage 2a of the cylindrical member 2 to provide a shear tube. On the other hand, there is a shaft member 1 fixed with a locking member 4 for locking the end portion of the shear tube 3 (see Japanese Patent Publication No. 63-30527).

When pressure oil is supplied to the hydraulic passage 2a, the inner peripheral surface of the cylindrical member 2 is reduced in diameter and pressed against the outer peripheral surface of the shaft member 1. As a result, the shaft member 1 and the tubular member 2 are frictionally coupled, and torque is transmitted between the shaft member 1 and the tubular member 2. Then, the shaft member 1 and the tubular member 2 are loaded with a load equal to or more than a predetermined value, the inner peripheral surface of the tubular member 2 slips, and the relative position around the axis between the axial member 1 and the tubular member 2 changes. At this time, the engaging member 4 cuts the end of the shear tube 3, and the pressure oil in the hydraulic passage 2a is discharged to the outside. As a result, the frictional coupling between the shaft member 1 and the tubular member 2 is released, and torque is no longer transmitted between the shaft member 1 and the tubular member 2.

[0004]

[Problems to be solved by the device]

 However, the conventional torque limiter described above has a problem that the torque capacity is relatively small because the area of the friction surface is limited by the shaft diameter and the shaft length of the shaft member 1. In addition, since the hydraulic pressure is constantly applied for use, there is a problem that the set torque is likely to drop due to oil leakage.

Further, in the above-mentioned conventional torque limiter, when the torque limiter is operated, the shear tube 3 is cut and the oil in the hydraulic slit 2a is discharged. Therefore, when returning, the hydraulic slit 2a is replenished with oil. Moreover, there is a problem that the shear tube 3 needs to be replaced with a new one.

Therefore, an object of the present invention is to provide a torque limiter which has a high torque transmission capability, has no fluctuation or reduction in the torque transmission capability, and does not require replacement of parts or replenishment of oil at the time of restoration. It is in.

[0007]

[Means for Solving the Problems]

 In order to achieve the above object, a torque limiter of the present invention comprises a shaft member having an outer peripheral surface with a spline, a cylindrical member having an inner peripheral surface with a spline, and a non-rotatably engaged spline of the shaft member. The shaft side friction plates, which are movably guided in the axial direction, and non-rotatably engaged with the spline of the tubular member, and guided so as to be movable in the axial direction, and are alternately arranged between the shaft side friction plates. An intervening cylinder-side friction plate, a piston that presses the shaft-side friction plate and the cylinder-side friction plate into axial contact with each other, a first clutch member on the friction plate side, and an axial direction on the piston side. A second clutch member on the piston side having an inclined surface inclined with respect to the first clutch member, and an opposed surface of the second clutch member opposed to the first clutch member, and a first clutch opposed to the second clutch member. On the opposite side of the member Each has a convex portion extending in the radial direction, and when the tubular member is mounted on the shaft member, the convex portion of the first clutch member and the convex portion of the second clutch member are opposed to each other and pressed against each other. When the first clutch member presses the friction plate and the relative position around the shaft of the shaft member and the tubular member changes, the relative position around the shaft of the first clutch member and the second clutch member changes. As a result, the convex portion of the first clutch member and the convex portion of the second clutch member no longer face each other, so that the first clutch member does not press the friction plate and the meshing of the piston. A pressing member provided at an end portion on the clutch side and having an inclined surface facing and in contact with the inclined surface of the second clutch member, a hydraulic chamber in which the piston is slidably fitted, and the pressing operation. Tappi Is characterized that you and a locking member for locking in place a ton.

[0008]

[Action]

 According to the above configuration, the convex portion of the first clutch member and the convex portion of the second clutch member of the dog clutch are opposed to each other, and then pressure oil is supplied to the hydraulic chamber to move the piston toward the friction plate. The friction plates are slid and pressed by the piston through the pressing member and the meshing clutch, and the piston is locked in a predetermined position by the lock member, and then the pressure oil in the hydraulic chamber is drained. . When the shaft member or the tubular member is loaded with a load equal to or more than a predetermined value during use and the positions of the shaft member and the tubular member around the axis change, the first clutch member and the second clutch member of the above-mentioned mesh clutch. The relative position around the axis of is changed so that the convex portion of the first clutch member and the convex portion of the second clutch member do not face each other and the first clutch member and the second clutch member mesh with each other. The first clutch member does not press the friction plate. Then, the frictional coupling of the friction plates is released, and torque is not transmitted between the shaft member and the tubular member.

Since the convex portions of the first clutch member and the second clutch member are in contact with each other, the second clutch member and the pressing member are in contact with each other on the inclined surface. When the positions of the shaft member and the tubular member around the axis change, the slip between the first clutch member and the second clutch member occurs earlier than the slip between the second clutch member and the pressing member, and the torque Is released. Therefore, wear of the pressing member is prevented, and even after long-term use, it is only necessary to repair or replace the dog clutch.

Further, according to the present invention, since the shaft member and the tubular member are connected through the frictional connection by the plurality of friction plates, the area of the frictional surface of the frictional connection becomes wider than that of the conventional example. , The torque capacity per given size becomes large.

Further, according to the present invention, after the piston is locked by the lock member, the piston continues to press the friction plate even if the hydraulic pressure in the hydraulic chamber is lowered, so that the conventional hydraulic pressure is used. Unlike the example, there is no decrease in the set torque due to oil leakage, and there is no variation or decrease in torque transmission capacity. Therefore, the torque transmission capacity equivalent to that at the time of initial setting can be maintained for a long period of time.

Further, according to the present invention, when the torque limiter is operated, the dog clutch is operated to release the torque. Therefore, when the torque limiter is operated, the shear tube is cut and oil is discharged from the hydraulic slit. Unlike, there is no need to replenish oil or replace parts.

[0013]

【Example】

 Hereinafter, the present invention will be described in detail with reference to illustrated embodiments.

As shown in FIG. 1, this embodiment has a shaft member 11 and a tubular member 12. A flange portion 11a is provided on the shaft member 11, and an axial convex spline 11b is formed on the outer peripheral surface of the tip portion of the shaft member 11 as shown in FIG. The cylindrical member 12 is provided with a flange portion 12a, and an axial concave spline 12b is formed on the inner peripheral surface of the base portion of the cylindrical member 12, as shown in FIG.

As shown in FIG. 1, a plurality of shaft side friction plates 14 and a plurality of cylinder side friction plates 13 are interposed between the convex splines 11 b of the shaft member 11 and the concave splines 12 b of the cylinder member 12. It is set up. A tip member 28 that axially supports the friction plate 14 is bolted to the tip surface of the shaft member 11. A bearing 35 is provided between the outer peripheral surface of the tip member 28 and the inner peripheral surface of the tubular member 12.

As shown in FIG. 2, the shaft-side friction plate 14 is formed on the outer periphery that is slightly smaller than the inner peripheral surface of the cylindrical member 12, and is fitted to the convex spline 11 b of the shaft member 11 on the inner periphery. It has a concave portion 14a. The shaft side friction plates 14, ..., 14 are guided by the convex splines 11 b so as to be movable in the axial direction.

As shown in FIG. 3, the cylinder side friction plate 13 is formed on the inner circumference slightly larger than the outer peripheral surface of the shaft member 11, and fits on the outer circumference of the concave spline 12 b of the cylinder member 12. It has a convex portion 13a. The cylinder-side friction plates 13, ..., 13 are movably guided by the concave splines 12b while being alternately interposed between the shaft-side friction plates 14 ,.

As shown in FIG. 1, a sleeve 30 is fitted on the outer peripheral surface of the base of the shaft member 11. A piston 22 is fitted between the sleeve 30 and the shaft member 11. A seal 36 and a seal 37 are provided between the piston 22 and the sleeve 30 and between the piston 22 and the shaft member 11. The piston 22 forms a hydraulic chamber 15 and is movable in the axial direction in the hydraulic chamber 15. The sleeve 30 is provided with an oil supply passage 30a communicating with the hydraulic chamber 15.

A male screw 22a is formed on the outer peripheral surface of the tip portion of the piston 22, and the screw 32a is screwed to the male screw 22a to form the inner peripheral surface of the lock member 32. . A bearing 38 is provided between the tip of the piston 22 and the cylindrical member 12.

A pressing member 23 is fixed to the tip of the piston 22 with a pin 24. The front end of the pressing member 23 has an inclined surface 23a that slopes downward toward the front. The pressing member 23 has a concave spline 23b that fits into the spline 11b of the shaft member 11, and is guided by the spline 11b of the shaft member 11 to slide in the axial direction.

Further, a meshing clutch 27 formed by a first clutch member 25 and a second clutch member 26 is arranged between the pressing member 23 and the shaft side friction plate 14.

The second clutch member 26 has an inclined surface 26 a on the pressing member 23 side, which is in contact with the inclined surface 23 a of the pressing member 23. Further, the second clutch member 26 has a convex portion 26b extending in the radial direction on the facing surface facing the first clutch member 25. Further, the first clutch member 25 has a convex portion 25a extending in the radial direction on the facing surface facing the second clutch member 26. Further, the first clutch member 25 has a convex spline 25b that fits into a concave spline 12b formed on the inner peripheral surface of the cylindrical member 12, and is guided by the concave spline 12b of the cylindrical member 12. It is designed to slide in the axial direction.

As shown in FIG. 4 which is a sectional view taken along the line CC of FIG. 1, the convex portions 26 b of the second clutch member 26 are arranged at substantially equal intervals in the circumferential direction. Further, the convex portions 25a of the first clutch member 25 are also arranged at substantially equal intervals in the circumferential direction, similarly to the convex portion 26b of the second clutch member 26.

According to the above configuration, as shown in FIG. 6A, the convex portion 25a of the first clutch member 25 of the dog clutch 27 and the convex portion 26b of the second clutch member 26 are opposed to each other. In this state, pressure oil is supplied from the oil supply passage 30a to advance the piston 22 toward the friction plates 14 and 13, and the pressure member 23, the second clutch member 26, and the first clutch member 25 are passed. By pressing and pressing the shaft side friction plate 14 and the cylinder side friction plate 13 into contact with each other, the shaft member 11 and the cylinder member 12 are frictionally coupled.

When the piston 22 is moved to a predetermined position and the initial setting of the torque by the pressure contact of the friction plates 13 and 14 is completed, the female screw 32 a of the lock member 32 is screwed into the male screw 22 a of the piston 22, The lock member 30 is moved to the sleeve 30 side to bring the lock member 32 into contact with the end surface of the sleeve 30. Thus, the piston 22 is locked in place by the lock member 32.

After that, the hydraulic pressure in the hydraulic chamber 15 is lowered from the oil supply passage 30a. At this time, since the piston 22 is locked at the predetermined position by the lock member 26, it does not move backward toward the oil supply passage 30a.

When the use is started in this state, and the shaft member 11 and the tubular member 12 are subjected to a load of a predetermined value or more during use, and the positions of the shaft member 11 and the tubular member 12 around the axes change, Since the first clutch member 25 of the dog clutch 27 is spline-fitted to the tubular member 12, it rotates about the axis together with the tubular member 12.

Further, at this time, since the second clutch member 26 is in contact with the pressing member 23 on the inclined surface 26a, it is in contact with the first clutch member 25 on the convex portion 26b. The frictional force between the second clutch member 26 and the pressing member 23 is larger than the frictional force between the second clutch member 26 and the first clutch member 25. Therefore, slippage occurs between the second clutch member 26 and the first clutch member 25, and between the friction plates 13 and 14, and the second clutch member 26 is pushed together with the pressing member 23 and the shaft member 11. Rotate around the axis. The frictional force acting on the second clutch member 26 will be described in more detail. As shown in FIG. 5, when the inclination angle of the inclined surface 26a is θ, the force F applied to the inclined surface 26a and the convex portion 26b are The relationship with the force P that presses the convex portion 25a is as shown in the following formula 1.

[0029]

F = P / sin θ Therefore, when 0 ° <θ <90 °, F> P holds, and the second clutch member 26 is more than the frictional force between the second clutch member 26 and the first clutch member 25. The frictional force between 26 and the pressing member 23 is greater.

Even if the friction coefficient between the clutch members 25 and 26 takes a value larger than the friction coefficient between the pressing member 23 and the second clutch member 26, the inclination angle θ is set. Thus, the frictional force between the clutch members 25 and 26 can be made smaller than the frictional force between the pressing member 23 and the second clutch member 26.

In this way, the dog clutch 27 changes from the state shown in FIG. 6A to the state shown in FIG. 6B, and the convex portion 25a of the first clutch member 25 and the second clutch 25 are changed. The convex portion 26b of the latch member 26 slips, and the dog clutch 27 is brought into an engaged state. Then, the first clutch member 25 does not press the friction plate 14 and slips between the pressing member 23 and the second clutch member 26 and between the friction plates 13 and 14, and the friction between the shaft member 11 and the tubular member 12 occurs. The coupling is released and torque is no longer transmitted.

When returning the torque transmission, the lock member 32 is screwed to move the lock member 32 to the tip side of the piston 22 so that the piston 22 is moved to the oil supply passage 30a side. After the movement, the return lever 39 shown in FIG. 4 is set in the screw hole 26c of the second clutch member 26, and the return lever 39 is moved from the Y position shown in FIG. 4 (the position after the torque limiter operation). By rotating the second clutch member 26 toward the piston 22 side by rotating the second clutch member 26 to the X position (set position), the second clutch member 26 is rotated around the axis, and the convex portion of the second clutch member 26 is rotated. 26b and the convex portion 25a of the first clutch member 25 are in phase with each other. After that, pressure oil is supplied from the hydraulic pump to the oil supply passage 30a to move the piston 22 to the friction plates 14 and 13 side, and the piston 22 is locked by the lock member 32. After that, the hydraulic pressure is lowered from the oil supply passage 30a, the return lever 37 is removed, and the return is completed.

As described above, according to the above-described embodiment, since the shaft member 11 and the tubular member 12 are coupled through the friction coupling by the plurality of friction plates 13 and 14, the friction coupling can be performed as compared with the conventional example. The area of the friction surface of can be widened, and the torque capacity per given size can be increased.

Further, after the piston 22 is locked by the lock member 32, the hydraulic pressure in the hydraulic chamber 15 is lowered. Therefore, unlike the conventional example in which the hydraulic pressure is constantly applied for use, there is no decrease in the set torque due to oil leakage, and the torque is reduced. There is no variation or decrease in transmission capacity. Therefore, the torque transmission capacity equivalent to that at the time of initial setting can be maintained for a long time.

Further, since the dog clutch 27 operates to release the torque when the torque limiter operates, unlike the conventional example in which the shear tube is cut and the oil is discharged from the hydraulic slit when the torque limiter operates, the oil No need to replenish or replace parts.

In the above embodiment, the inclined surface 26a of the second clutch member 26 and the inclined surface 23a of the pressing member 23 are both flat, but the inclined surface 23a of the pressing member 23 is a curved surface, and the second clutch member The inclined surface 26a of 26 may be a flat surface. The reverse is also possible. Further, both the inclined surface 23a of the pressing member 23 and the inclined surface 26b of the second clutch member 26 may be curved.

Further, in the above embodiment, the piston 22 and the pressing member 23 are separate bodies, but the piston 22 and the pressing member 23 may be integrated.

[0038]

[Effect of device]

 As is clear from the above, the torque limiter of the present invention, when the shaft member or the cylindrical member is loaded with a load of a predetermined value or more during use, and the positions of the shaft member and the cylindrical member around the axis change, the meshing clutch is The relative positions of the first clutch member and the second clutch member around the axis change, and the convex portions of the first clutch member and the convex portions of the second clutch member do not face each other and mesh with each other, and the first clutch The member no longer presses each friction plate, and the frictional coupling of each friction plate is released.

As described above, according to the present invention, since the shaft member and the tubular member are connected to each other through the frictional connection of the plurality of friction plates, the area of the frictional surface of the frictional connection is larger than that of the conventional example. , The torque capacity per given size can be increased.

Further, according to the present invention, after the piston is locked by the lock member, the piston continues to press each friction plate through the meshing clutch even if the hydraulic pressure in the hydraulic chamber is lowered, so that the hydraulic pressure is constantly applied. Unlike the conventional example, which is used for a long time, there is no decrease in the set torque due to oil leakage, and there is no variation or decrease in torque transmission capacity. Therefore, the torque transmission capacity equivalent to that at the time of initial setting can be maintained for a long time.

Further, according to the present invention, since the dog clutch operates to release the torque when the torque limiter operates, the shear tube is cut when the torque limiter operates to discharge the oil from the hydraulic slit. In contrast, it is possible to eliminate the need for oil supply and parts replacement.

Further, according to the present invention, the first clutch member and the second clutch member are in contact with each other by the convex portions, whereas the second clutch member and the pressing member are in contact with each other on an inclined surface. Thus, when the positions of the shaft member and the tubular member around the axis change, the slip between the first clutch member and the second clutch member is smaller than the slip between the second clutch member and the pressing member. Since the torque is released in advance, wear of the pressing member can be prevented, and even after long-term use, the dog clutch only needs to be repaired or replaced.

[Brief description of drawings]

FIG. 1 is a side sectional view of an embodiment of a torque limiter of the present invention.

FIG. 2 is a sectional view taken along the line AA of FIG.

3 is a cross-sectional view taken along the line BB of FIG.

4 is a cross-sectional view taken along the line CC of FIG.

FIG. 5 is a diagram illustrating a force that acts on the dog clutch of the above embodiment.

FIG. 6 is an operation explanatory view of the above-mentioned mesh clutch.

FIG. 7 is a sectional view of a conventional torque limiter.

[Explanation of symbols]

11 ... Shaft member, 11b ... Spline, 12 ... Cylindrical member, 1
2b ... Spline, 13, 14 ... Friction plate, 15 ... Hydraulic chamber, 22 ... Piston, 23 ... Pressing member, 25 ... First clutch member, 26 ... Second clutch member, 30 ... Sleeve,
32 ... Lock member.

Claims (1)

[Scope of utility model registration request] 1. A shaft member having a spline on an outer peripheral surface, a tubular member having a spline on an inner peripheral surface, and a plurality of shaft members which are non-rotatably engaged by the spline of the shaft member and are movably guided in an axial direction. A plurality of shaft side friction plates, non-rotatably engaged with the spline of the cylinder member, guided movably in the axial direction, and alternately arranged between the shaft side friction plates; and A piston that presses the shaft-side friction plate and the cylinder-side friction plate in the axial direction for pressure contact, a first clutch member on the friction plate side, and a piston side having an inclined surface inclined to the piston direction on the piston side. A second clutch member is provided, and a facing surface of the second clutch member facing the first clutch member and a facing surface of the first clutch member facing the second clutch member respectively extend in the radial direction. The convex portion is formed and When the tubular member is mounted on the shaft member, the convex portion of the first clutch member and the convex portion of the second clutch member are opposed to each other and press each other, and the first clutch member presses the friction plate. When the relative position around the axis of the shaft member and the tubular member changes, the relative position around the axis of the first clutch member and the second clutch member changes, and the convex portion of the first clutch member and the above A meshing clutch, in which the convex portion of the second clutch member does not face each other and the first clutch member does not press the friction plate, and the piston is provided at an end portion of the piston on the meshing clutch side,
A pressing member having an inclined surface facing and in contact with the inclined surface of the second clutch member, a hydraulic chamber in which the piston is slidably fitted, and a lock for locking the pressed piston at a predetermined position. A torque limiter comprising: a member.