JP2560764Y2 - Torque limiter - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement of a torque limiter.

[0002]

2. Description of the Related Art Conventionally, as a torque limiter, as shown in FIG. 6, an inner peripheral surface of a cylindrical member 2 is fitted into an outer peripheral surface of a shaft member 1 to supply pressure oil to a hydraulic passage 2a of the cylindrical member 2. While the shaft member 1 is sealed with a shear tube 3, there is a shaft member 1 fixed by a locking member 4 for locking an end of the shear tube 3 (see Japanese Patent Publication No. Sho 63-30527).

The inner peripheral surface of the cylindrical member 2 is reduced in diameter by the pressure oil in the hydraulic passage 2 a and pressed against the outer peripheral surface of the shaft member 1. As a result, the shaft member 1 and the cylindrical member 2 are frictionally coupled, and torque is transmitted. Then, a load equal to or more than a predetermined value is applied to the shaft member 1 and the cylindrical member 2, and the inner peripheral surface of the cylindrical member 2 slips,
When the position of the shaft member 1 and the cylindrical member 2 around the axis changes, the end of the shear tube 3 is cut by the locking member 4, and the hydraulic oil in the hydraulic passage 2a is discharged to the outside. As a result, the frictional connection between the shaft member 1 and the cylindrical member 2 is released, so that torque cannot be transmitted.

[0004]

However, the above-described conventional torque limiter has a problem that the torque transmission capacity is low because the area of the friction surface is limited. Also, since it is a type that always uses hydraulic pressure, after refueling,
When oil leaks from the filler port, the internal pressure changes and the torque transmission capability varies, and when oil leaks from a fitting portion such as a valve during use, the internal pressure changes and the torque transmission capability lowers.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a torque limiter having a high torque transmission capability and having no variation or reduction in the torque transmission capability.

[0006]

In order to achieve the above object, the present invention provides a cylinder having an axial spline on an outer peripheral surface and a spline and a locking serration on an inner peripheral surface. Member, a plurality of shaft-side friction plates guided movably in the axial direction by splines of the shaft member, and alternately guided between the shaft-side friction plates guided movably in the axial direction by the splines of the cylindrical member. A cylinder-side friction plate interposed, a piston for pressing the shaft-side friction plate and the cylinder-side friction plate in an axial direction to press them against each other, and a piston interposed between the piston and the friction plate closest to the piston; A pressing spring, a hydraulic chamber in which the piston is slidably fitted, and a locking serration provided on the cylindrical member, which is locked in an axial direction, and locked by a predetermined rotation when the cylindrical member rotates a predetermined time. Unlock with serration Has a stop serrations, is characterized by comprising a locking member for locking the piston is pressed actuated by pressure oil of the hydraulic chamber at a predetermined position.

[0007]

According to the torque limiter of the present invention, pressure oil is supplied to the hydraulic chamber to slide the piston in the direction of the friction plate,
Each of the friction plates is pressed by the piston via a pressing spring to make pressure contact with the friction plate, and after the piston is locked at a predetermined position by a lock member, the pressure oil in the hydraulic chamber is drained. When a load of a predetermined value or more is applied to the shaft member or the cylinder member during use, and the position of the shaft member and the cylinder member around the axis changes, the engagement serration of the lock member by the engagement serration of the cylinder member is changed. The suspension is released. As a result, the lock member can move in the axial direction, and the piston moves in the anti-pressing direction by the pressing spring to release the frictional contact between the friction plates. Will not be transmitted.

As described above, since the shaft member and the cylindrical member are frictionally coupled by the plurality of friction plates, the area of the friction surface is increased, and the torque transmitting capability is increased. Therefore, it is easy to manufacture a torque limiter having a high torque capacity. Since the initial setting of torque is performed by hydraulic pressure, torque setting is easy, and after setting torque, pressure oil is drained and the piston is locked by the lock member. Does not occur. Therefore, the same torque transmission capability as that at the time of the initial setting can be maintained for a long time.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail with reference to the illustrated embodiments. As shown in FIG. 1, a shaft member 11 and a cylindrical member 12 are provided. This shaft member 11 has a flange 11
a is provided, and a convex spline 11b (see FIG. 3) in the axial direction is formed on the outer peripheral surface of the front end of the shaft member 11.
Is formed with a tapered surface 11c. The tubular member 12 is provided with a flange portion 12a, and a concave spline 12b (see FIG. 4) of the tubular member is formed on the inner peripheral surface of the base of the tubular member 12.

As shown in FIG. 3, a plurality of sheets are formed on the outer periphery slightly smaller than the inner peripheral surface of the cylindrical member 12 and have concave portions 14a on the inner periphery that fit into the convex splines 11b of the shaft member 11. , 14 are provided, and the shaft-side friction plates 14,..., 14 are guided by the convex splines 11b so as to be movable in the axial direction.

As shown in FIG. 4, a plurality of sheets are formed on the inner periphery slightly larger than the outer peripheral surface of the shaft member 11 and have a convex portion 13a on the outer periphery which fits into the concave spline 12b of the cylindrical member 12. , 13 are provided, and the cylinder-side friction plates 13, ..., 13 are provided with the shaft-side friction plates 14, ..., 1
4 and is guided by the concave spline 12b so as to be movable in the axial direction.

As shown in FIGS. 1 and 2, a hydraulic chamber 1 is provided between the tip of the tubular member 12 and the inner peripheral surface of the tubular member 12.
The sleeve 16 that forms the fifth member 5 is integrally fitted, and a flange 16 a of the sleeve 16 is provided with an oil supply port 16 b that communicates with the hydraulic chamber 15. This sleeve 1
6, an internal thread 16c is formed on the inner peripheral surface.

A piston 17 is fitted in the hydraulic chamber 15 so as to be movable in the axial direction, and a plunger 19 is fitted to the tip of the piston 17 via a plurality of disc springs 18. When pressure oil is supplied to the hydraulic chamber 15, the piston 17 moves rightward in the drawing, and the disc springs 18,
The plunger 19 moves to the right via 18, and the shaft-side friction plate 14 and the cylinder-side friction plate 13 are pressed to the right by the plunger 19 and pressed against each other.

On the other hand, as shown in FIG. 2, the inner peripheral surface is fitted to the base of the shaft member 11 via a bush 23 so as to be movable in the axial direction, and the female screw 16c of the sleeve 16 is fitted to the outer peripheral surface.
Is provided with a sleeve-shaped lock member 20 having a male screw 20a that is screwed into the lock member 20.

As shown in FIG. 5, on the outer peripheral surface of the lock member 20, an axial serration 20b is formed at a depth reaching the bottom of the male screw 20a.
On the inner peripheral surface of the female screw 16c, an axial locking serration 16d is formed at a depth reaching the bottom of the female screw 16c. When the male screw 20a of the lock member 20 is screwed into the female screw 16c of the sleeve 16, the lock member 20 is engaged in the axial direction at the rotation position where the lock serration 20b of the lock member 20 overlaps the lock serration 16d of the sleeve 16. Is stopped. Therefore, the lock member 20 is locked from moving leftward in FIG. On the other hand, the locking serrations 16d of the sleeve 16 are
At the rotational position where 0b does not overlap, the locking of the lock member 20 is released.

As shown in FIG. 2, the lock member 20
Locks the piston 17 in place at the tip,
At the rear end of the lock member 20, a set screw 21 corresponding to the tapered surface 11c of the shaft member 11 is set.

According to the above configuration, when pressure oil is supplied from the oil supply port 16b of the sleeve 16 to the hydraulic chamber 15, the piston 1
7, the plunger 19 moves rightward via the disc springs 18 and 18 to press the shaft-side friction plate 14 and the cylinder-side friction plate 13 to be in pressure contact with each other, so that the shaft member 11 and the cylinder member 12 are frictionally connected. Is done.

When the piston 17 is moved to a predetermined position and the initial setting of the torque by pressing the friction plates 13 and 14 is completed, the external thread 20a of the lock member 20 is screwed into the internal thread 16c of the sleeve 16, The front end of the lock member 20 is brought into contact with the rear end of the piston 17. By adjusting the rotational position of the lock member 20 at this contact position, the sleeve 1
The locking serration 20b of the lock member 20 is superimposed on the locking serration 16d of No.6. Thereby, the lock member 2
0 is locked so as not to move leftward in FIGS. 1 and 2, and the piston 17 is locked at a predetermined position. At this position, when the set screw 21 of the lock member 20 is screwed into contact with the tapered surface 11c of the shaft member 11, the rotation of the lock member 20 is regulated. Since the set screw 21 is merely brought into contact with the tapered surface 11c, when the engagement between the locking serration 16d and the locking serration 20b is released, the locking member 20 moves leftward in the axial direction in FIG. Will be possible.

Thereafter, the pressure oil in the hydraulic chamber 15 is drained from the oil supply port 16b of the sleeve 16. At this time, since the piston 17 is locked at the predetermined position by the lock member 20, it does not move leftward.

In this state, use is started, and a load equal to or more than a predetermined value is applied to the shaft member 11 and the cylindrical member 12 during use.
When the position of the shaft member 11 and the cylindrical member 12 around the axis changes, the locking serrations 20b of the lock member 20 by the locking serrations 16d of the sleeve 16 integrated with the cylindrical member 12.
Is released.

As a result, the lock member 20 moves to the left in FIG. 1 together with the piston 17 by the urging force of the disc springs 18, 18.
Is stopped, the frictional connection between the shaft member 11 and the cylindrical member 12 is released, and the torque is not transmitted.

In the above configuration, the shaft member 11 and the cylindrical member 1
2 is frictionally coupled by the plurality of friction plates 13 and 14, so that the area of the friction surface is large and the torque transmission capability is high. Further, since the initial setting of the torque is performed not by the lock member 20 but by the piston 17 by the hydraulic pressure of the hydraulic chamber 15, the torque can be easily set. After setting the torque, the piston 1
Since the lock member 7 is locked by the lock member 20, no oil pressure is required, and the torque transmission capability does not vary due to oil leakage.

[0023]

As is clear from the above description, in the torque limiter of the present invention, since the shaft member and the cylindrical member are frictionally connected by a plurality of friction plates, the area of the friction surface is large. Therefore, it is easy to manufacture a torque limiter having a high torque transmission capability and a high torque capacity. Further, since the initial setting of the torque is performed by the hydraulic pressure, the torque can be easily set.
In addition, after setting the torque, the pressure oil is drained and the piston is locked by the lock member, so there is no variation or reduction in torque transmission capacity due to oil leakage, and the same torque transmission capacity as the initial setting is maintained for a long time it can.

[Brief description of the drawings]

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

FIG. 2 is a partially enlarged view of FIG. 1;

FIG. 3 is a sectional view taken along line AA of FIG. 1;

FIG. 4 is a sectional view taken along line BB of FIG. 1;

FIG. 5 is an enlarged view of a main part taken along line CC of FIG. 1;

FIG. 6 is a sectional view of a conventional torque limiter.

[Explanation of symbols]

11: shaft member, 11b: convex spline, 12: cylindrical member,
12b: concave spline, 13, 14: friction plate, 15: hydraulic chamber, 16: sleeve, 16d: locking serration, 17
... Piston, 18 ... Belleville spring, 20 ... Lock member, 20b
... locking serrations.

Claims (1)

(57) [Scope of request for utility model registration] 1. A shaft member having an axial spline on an outer peripheral surface, a cylindrical member having an axial spline and a locking serration on an inner peripheral surface, and a guide movably in an axial direction by a spline of the shaft member. A plurality of shaft-side friction plates, and a cylinder-side friction plate that is guided movably in the axial direction by splines of the cylinder member and that is alternately interposed between the shaft-side friction plates; A piston that presses the cylinder-side friction plate in the axial direction and presses the cylinder-side friction plate, a pressing spring interposed between the piston and the friction plate closest to the piston, and the piston is slidably fitted. A hydraulic chamber, and a locking serration that is locked in the axial direction by a locking serration provided on the cylindrical member, and is unlocked from the locking serration of the cylindrical member when rotated a predetermined time,
A lock member that locks, at a predetermined position, a piston pressed by the hydraulic oil in the hydraulic chamber at a predetermined position.