JPH0587149A - Torque limiter - Google Patents

Abstract

PURPOSE:To restore with a simple work without requiring renewal parts at the restoring time in a torque limiter. CONSTITUTION:An opening member 25 is fitted to a shaft member 11 so as to open the opening 13b of the oil pressure passage 13f of a cylinder member 12 by the opening member 25 when the shaft circumferential position to the cylinder member 12 is changed. At the restoring time, the opening part 13b can be closed again by setting the shaft circumferential position between the shaft member 11 and cylindrical member 12 to the position before change.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to improvements in torque limiters.

[0002]

2. Description of the Related 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 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 to which a locking member 4 for locking the end of the shear tube 3 is fixed (see Japanese Patent Publication No. 63-30527).

The pressure oil in the hydraulic passage 2a reduces the diameter of the inner peripheral surface of the cylindrical member 2 and presses it against the outer peripheral surface of the shaft member 1. As a result, the shaft member 1 and the tubular member 2 are coupled to each other and the torque is transmitted. When the shaft member 1 or the tubular member 2 is loaded with a load equal to or more than a predetermined value and the inner peripheral surface of the tubular member 2 slips, and the positions of the shaft member 1 and the tubular member 2 around the axes change, the locking is performed. The end of the shear tube 3 is cut by the member 4, and the pressure oil in the hydraulic passage 2a is discharged to the outside. This prevents the inner peripheral surface of the tubular member 2 from being pressed against the outer peripheral surface of the shaft member 1,
The connection between the shaft member 1 and the tubular member 2 is released, and torque is not transmitted.

[0004]

However, in the above-mentioned conventional structure, the shear tube 3 is cut, so that the shear tube 3 needs to be replaced at the time of restoration, so that the cost of parts is high and the replacement work is also difficult. The problem is that it is annoying. There is also a problem that a separate mechanism for bleeding air from the hydraulic passage 2a of the tubular member 2 is required.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide a torque limiter that does not require replacement parts at the time of restoration, can be restored by a simple operation, and does not require an air bleeding mechanism separately.

[0006]

To achieve the above object, the present invention provides a shaft member, a tubular member having a hydraulic passage for pressing an inner peripheral surface against an outer peripheral surface of the shaft member, and the shaft member. It is characterized in that it is provided with the cylindrical member and an opening member that opens the opening of the hydraulic passage when the position around the axis changes.

[0007]

According to the torque limiter of the present invention, an opening member is attached to the shaft member, and when the position around the shaft changes with the tubular member, the opening member opens the opening of the hydraulic passage to release the pressure oil in the hydraulic passage. Discharge to the outside. Then, at the time of restoration, if the positions of the shaft member and the tubular member around the axis are aligned with the positions before the change, the opening can be closed again. This allows easy restoration without replacement parts. Also, air can be vented by opening and closing the opening.

[0008]

The present invention will be described in detail below with reference to the embodiments shown in the drawings. 1 to 3 show the first embodiment. The sleeve 13 is integrally fitted to the tubular member 12, and the inner peripheral surface of the sleeve 13 is fitted to the outer peripheral surface of the shaft member 11.

A flange portion 13a rising outward in the radial direction is provided at one end of the sleeve 13, and a radial opening 13b is formed on the outer peripheral surface of the flange portion 13a. The upper portion of the opening 13b has a large diameter hole 13c, the middle portion has a female screw hole 13d, and the lower portion has a small diameter hole 13e.

An annular hydraulic passage 13f is formed in the sleeve 13 by a slit long in the axial direction, and the hydraulic passage 13f communicates with the small diameter hole 13e of the opening 13b. The sleeve 13 is provided with an inlet (not shown) for supplying pressure oil to the hydraulic passage 13f.

A valve 15 is attached to the opening 13b of the sleeve 13. This valve 15 includes a first sleeve 16 and a second sleeve 1 as shown in detail in FIG.
7, the upper male thread 16a of the first sleeve 16 and the lower female thread 17a of the second sleeve 17 are screwed together and integrally connected.

At the lower part of the first sleeve 16, a cylindrical portion 16b fitted into the small diameter hole 13e of the opening 13b and a male screw portion 16c screwed into the female screw hole 13d of the opening 13b.
And are provided. A seal ring 1 for oil-tightly sealing the small diameter hole 13e on the outer periphery of the cylindrical portion 16b.
8 is fitted.

A ball (valve) 19 is vertically movably fitted into the center hole 16d of the first sleeve 16, and a valve seat 16e is formed at the upper part of the center hole 16d to which the moved ball 19 abuts. Has been done. A plug 20 having an oil passage hole 20a is screwed to the lower portion of the center hole 16d, and a spring 21 is provided between the plug 20 and the ball 19 so that the ball 19 comes into contact with the valve seat 16e. It is biased in the moving direction.

The second sleeve 17 is provided with the release port 13
It is loosely fitted in the large diameter hole 13c of b. A rod 22 is fitted in a center hole 17b of the second sleeve 17 so as to be able to move up and down, and when the rod 22 descends, the ball 22 can be pushed downward by a lower portion 22a of the rod 22. A spring 23 compressed between the flange portion 22b of the rod 22 and the upper wall 17c of the central hole 17b of the second sleeve 17.
Thus, the rod 22 is urged in the descending direction where it abuts on the ball 19. An oil drain hole 17d is formed on the side wall of the second sleeve 17 so as to face the large diameter hole 13c of the opening 13b. Incidentally, 24 is a retaining ring of the rod 22.

The spring 23 of the second sleeve 17
Is set to be stronger than the spring 21 of the first sleeve 16. In addition, the spring 23 of the second sleeve 17
Is set so that the ball 19 of the first sleeve 16 does not push the ball 19 downward by the rod 22 when the ball 19 of the first sleeve 16 is in contact with the valve seat 16e by the pressure oil in the hydraulic passage 13f of the sleeve 13.

A push plate 25 rising outward in the radial direction is fixed to the outer peripheral surface of the shaft member 11 with bolts 26. The push plate 25 has a slight upper portion of the rod 22 of the valve 15. A fork portion 25a is provided to sandwich the gap. Then, the sleeve 13 of the tubular member 12
When the position of the shaft member 11 around the axis changes, the rod 22 is pushed downward by the fork portion 25a.

According to the configuration of the first embodiment, the shaft member 1
When the fork portion 25a of the push plate 25 of No. 1 is in a position to sandwich the upper portion of the rod 22 of the valve 15 and the pressure oil is supplied to the hydraulic passage 13f of the sleeve 13, the pressure oil of the hydraulic passage 13f is used for the valve. The ball 19 of 15 abuts on the valve seat 16e, and the valve 15 is closed.

Since the inner peripheral surface of the sleeve 13 is reduced in diameter by the pressure oil in the hydraulic passage 13f and pressed against the outer peripheral surface of the shaft member 11, the shaft member 11 and the tubular member 12 are coupled to transmit torque. It

On the other hand, when the load on the shaft member 11 or the tubular member 12 exceeds a predetermined value and the inner peripheral surface of the sleeve 13 slips and the positions of the shaft member 11 and the tubular member 12 around the axes change, Fork portion 25a of the push plate 25 of the member 11
The rod 22 of the valve 15 is pushed downward by.

Then, when the ball 19 is forcibly pushed downward by the rod 22 against the pressure oil in the hydraulic passage 13f and moves away from the valve seat 16e, the pressure oil in the hydraulic passage 13f is released from the oil passage hole of the plug 20. 20a, the central hole 16 of the first sleeve 16
d, discharged through the hole of the valve seat 16e, the center hole 17b of the second sleeve 17 and the oil drain hole 17d to the outside. As a result, the inner peripheral surface of the sleeve 13 is not pressed against the outer peripheral surface of the shaft member 11, so that the shaft member 11 and the tubular member 12 are uncoupled from each other and torque is not transmitted. At this time, the spring 23 of the rod 22 is stronger than the spring 21 of the ball 19, and the pressure oil is discharged to the outside from the hydraulic passage 13f.
6e, and then spring 23
The ball 19 is moved downward by the urging force of, and the hole of the valve seat 16e is largely opened.

Next, at the time of restoration, the shaft member 11 and the tubular member 1
When the position around the axis of 2 is adjusted to the position before the change, the fork portion 25a of the push plate 25 of the shaft member 11 moves to a position where the upper portion of the rod 22 of the valve 15 is sandwiched. At this time,
Since the pressure oil is not supplied to the hydraulic passage 13f, the ball 22 is moved downward by the rod 22 of the valve 15.

Next, when pressure oil is supplied to the hydraulic passage 13f, the ball 19 of the valve 15 contacts the valve seat 16e by this pressure oil, and the valve 15 is closed. The rod 22 is held in the raised position against the biasing force of the spring 23 by the pressure oil acting on the ball 19. The inner peripheral surface of the sleeve 13 is reduced in diameter by the pressure oil in the hydraulic passage 13f and pressed against the outer peripheral surface of the shaft member 11, so that the shaft member 11 and the cylindrical member 12 are coupled again and torque is transmitted.

In this way, the restoration can be repeated by simply adjusting the positions of the shaft member 11 and the cylindrical member 12 around the axes to the positions before the change and supplying pressure oil to the hydraulic passage 13f. No replacement parts are required, and restoration work can be performed easily and quickly. Further, the air in the hydraulic passage 13f can be evacuated by utilizing the gap between the ball 19 and the valve seat 16e, and a separate air bleeding mechanism is unnecessary.

4 to 6 show a second embodiment. Tube member 3
The inner peripheral surface of 0 is fitted into the outer peripheral surface of the shaft member 11. In addition,
Reference numerals 31 and 31 are bearings, and 32 and 32 are oil seals.

An annular hydraulic passage 30a is formed in the cylindrical member 30 by a slit that is long in the axial direction.
0a is provided with an oil injection passage 30c that extends radially outward and opens to the outer peripheral surface of the tubular member 30. Also,
An open passage 30e that extends axially from the middle of the oil injection passage 30c and has an opening 30d on the outer end surface of the tubular member 30.
Is provided.

The oil injection passage 30c is closed by a plug 33 so that it can be opened and closed. An oil seal (or O-ring) 34 (see FIG. 6) is provided at the opening 30d of the opening passage 30e.
(See) is provided.

An oil stopper plate 35 rising outward in the radial direction is fixed to the outer peripheral surface of the shaft member 11 with bolts 36. As shown in FIG. 6, the oil stopper plate 35 is provided with the opening 30d. It abuts the oil seal 34 to seal the opening 30d in an oiltight manner. When the positions of the cylindrical member 30 and the shaft member 11 around the axis change, the oil plug plate 35 separates from the oil seal 34 and opens the opening 30d.

According to the configuration of the second embodiment, the shaft member 1
When the oil plug plate 35 of No. 1 is in a position to seal the opening 30d of the tubular member 30 and pressure oil is being supplied to the hydraulic passage 30a of the tubular member 30, the hydraulic oil of the hydraulic passage 30a is used to press the tubular member 30. Since the inner peripheral surface of the shaft is reduced in diameter and pressed against the outer peripheral surface of the shaft member 11, the shaft member 11 and the tubular member 30 are coupled and torque is transmitted.

On the other hand, when the shaft member 11 or the cylindrical member 30 is loaded with a load of a predetermined value or more and the inner peripheral surface of the cylindrical member 30 slips, the positions of the shaft member 11 and the cylindrical member 30 around the axis change. Since the oil plug plate 35 separates from the oil seal 34 and opens the opening 30d, the pressure oil in the hydraulic passage 30a is discharged to the outside from the injection passage 30c through the opening 30d of the opening passage 30e. As a result, the inner peripheral surface of the tubular member 30 is no longer pressed against the outer peripheral surface of the shaft member 11, so that the coupling between the shaft member 11 and the tubular member 30 is released, and torque is not transmitted.

Next, at the time of restoration, the shaft member 11 and the tubular member 3
When the position around the axis of 0 is adjusted to the position before the change, the opening 30d of the tubular member 30 is closed by the oil plug plate 35 of the shaft member 11. After that, the plug 33 is removed and pressure oil is supplied from the oil injection passage 30c to the hydraulic passage 30a, and the oil injection passage 30c is closed again by the plug 33. The inner peripheral surface of the tubular member 30 is reduced in diameter by the pressure oil in the hydraulic passage 30a and pressed against the outer peripheral surface of the shaft member 11, so that the shaft member 11 and the tubular member 30 are re-coupled and torque is transmitted.

As described above, the restoration is performed by adjusting the positions of the shaft member 11 and the cylindrical member 30 around the axes to the positions before the change, and the oil stopper plate 3
Since it can be repeated by simply supplying pressure oil to the hydraulic passage 30a with the opening 30d closed at 5, the replacement parts as in the prior art are unnecessary, and the restoration work can be performed easily and quickly. Also, the air vent of the hydraulic passage 30a is opened by the opening 30d.
Can be performed by slightly opening, and a separate air bleeding mechanism is unnecessary.

[0032]

As is apparent from the above description, in the torque limiter of the present invention, the opening member is attached to the shaft member, and when the position around the axis of the tubular member changes, the hydraulic member opens the hydraulic passage of the tubular member. It is designed to open the mouth. Therefore, at the time of restoration, if the positions around the axis of the shaft member and the tubular member are aligned with the positions before the change, the opening can be closed again, so that it is possible to easily restore without the replacement parts as in the past. ..

[Brief description of drawings]

FIG. 1 is a sectional view of a torque limiter according to a first embodiment of the present invention.

2 is a rear view of the push plate of FIG.

3 is an enlarged cross-sectional view of the valve of FIG.

FIG. 4 is a sectional view of a torque limiter according to a second embodiment of the present invention.

5 is a rear view of the oil stopper plate of FIG.

6 is an enlarged sectional view taken along line AA of FIG.

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

[Explanation of symbols]

11 ... Shaft member, 12, 30 ... Cylindrical member, 13 ... Sleeve,
13b, 30d ... Opening port, 13f, 30a ... Hydraulic passage, 15 ...
Valve, 25 ... Push plate, 35 ... Oil stopper plate.

Claims (1)

[Claims] 1. A shaft member, a cylinder member having a hydraulic passage for pressing an inner peripheral surface onto an outer peripheral surface of the shaft member, and a cylinder member attached to the shaft member when the position around the shaft and the cylinder member changes. A torque limiter, comprising: an opening member that opens an opening of the hydraulic passage.