JP4164252B2 - Brake device for hydraulic motor - Google Patents

Description

[0001]
[Industrial application fields]
The present invention relates to a brake device for a hydraulic motor used in a general industrial machine.
[0002]
[Prior art]
As a brake device for such a conventional hydraulic motor, for example, as shown in Japanese Utility Model Publication No. 63-37497, a cylinder barrel rotatably supported with a shaft is supported in a casing, and inserted into the cylinder barrel so as to be slidable in the axial direction. A hydraulic motor having a swash plate that is slidable in contact with the heads of the plurality of pistons and is supported in the casing so as not to rotate relative to the rotation of the shaft; and a cylinder barrel integrated with the outer periphery of the cylinder barrel An annular friction plate that is rotated and fitted so as to be movable in the axial direction of the cylinder barrel; and a cylinder barrel that is disposed in the casing and is movable in the axial direction of the cylinder barrel and presses the friction plate against the casing. A brake piston for braking the rotation of an integral friction plate, and the brake piston is pressed against the friction plate Anda brake device having a spring disposed between the pacing and the brake piston, the spring had made of a plurality of compression coil springs were placed in a plurality of holes provided in the casing.
[0003]
[Problems to be solved by the invention]
However, in the above-mentioned Japanese Utility Model Publication No. 63-37497, a plurality of compression coil springs such as several to several tens are required to obtain a desired braking force, and these compression coil springs interfere with each other. Since it was put in a plurality of holes provided in the casing, the cost was high, and it took a lot of man-hours to pay close attention so that the compression coil springs would not fall apart during assembly.
For this reason, as shown in Japanese Patent Application Laid-Open No. 2000-80973, some use a disc spring instead of a compression coil spring. However, the disc spring itself is expensive, and the disc spring has a large spring load, so that a brake piston having a large pressure receiving area for releasing the brake is required, which increases the shape of the brake piston and further increases the cost.
[0004]
An object of the present invention is to provide a brake device for a hydraulic motor that solves the problems of the conventional brake device for a hydraulic motor and is inexpensive and easy to assemble a spring.
[0005]
[Means for Solving the Problems]
For this reason, the present invention provides a cylinder barrel that is supported in a casing so as to be rotatable together with the shaft, and a plurality of piston heads that are inserted in the cylinder barrel so as to be slidable in the axial direction. A hydraulic motor having a swash plate that is supported in the casing so as not to rotate relative to the ring, and an annular motor that is fitted to the outer periphery of the cylinder barrel so as to rotate integrally with the cylinder barrel and move in the axial direction of the cylinder barrel. A friction plate, a brake piston disposed in the casing and movable in the axial direction of the cylinder barrel, and pressing the friction plate against the casing to brake rotation of the friction plate integral with the cylinder barrel; and the brake piston A brake having a spring disposed between the casing and the brake piston to press against the friction plate A device and the, the,
The spring is composed of a plurality of compression coil springs, the compression coil springs are inserted into a plurality of holes provided in an annular cage, and the annular cage is fitted into an annular groove provided in a casing,
The plurality of holes of the annular cage are formed as eccentric holes or elliptical holes having an inner diameter that is slightly larger than the compression coil spring, and a part of the inner or outer wall of the plurality of holes is cut out. The above-described problems of the present invention have been solved by providing a brake device for a hydraulic motor.
[0006]
【The invention's effect】
With this configuration, an inexpensive compression coil spring can be used as the spring, and the plurality of compression coil springs are inserted into a plurality of holes provided in the annular cage so that the compression coil springs do not interfere with each other. Since the container is fitted in one annular groove provided in the casing, there is no need to provide holes for inserting a plurality of compression coil springs in the casing, and the cost is reduced, and the compression coil spring and the annular cage are combined. Since it is possible to assemble with a thing, it is not necessary to pay close attention so that the compression coil spring does not fall apart during assembly, the assembly of the spring becomes easy , and the hole and the compression coil in the circumferential direction of the annular cage A small gap is formed between the spring and a part of the inner wall of the plurality of holes (may be a part of the outer wall), so that the compression coil spring can be easily inserted. And compress When Le spring to brake the rotation of the friction plate of the cylinder barrel and integrally press friction plates through the brake piston, it is adapted miss Kakararu extraordinary force to the compression coil spring.
[0007]
Preferably, a part of the wall of the notched hole is elastic so that the compression coil spring can be easily inserted and does not fall after the compression coil spring is assembled, and the annular retainer is a shallow annular groove provided on the lid of the casing. As a result, the annular groove can be processed at low cost.
Preferably, a projection is provided on a part of the annular cage, and the projection is fitted to a key groove provided on the lid of the casing, so that a simple detent can be formed.
More preferably, the annular cage can be integrally formed of metal or synthetic resin, and can be made cheaper.
Further, the swash plate supported in the casing may be one in which the swash plate can be tilted so as to change the tilt angle.
[0008]
DETAILED DESCRIPTION OF THE INVENTION
Next, a hydraulic motor brake device according to an embodiment of the present invention will be described with reference to FIGS. The hydraulic motor shown in an overall view in FIG. 1 includes a cylinder barrel 6 that is rotatably supported in a casing 1 and 2 together with a shaft 3, and a plurality of pistons 4 that are inserted into the cylinder barrel 6 so as to be axially slidable. The head, the shoe 7, the shoe holder 8, and the swash plate 20 supported in the casings 1 and 2 so as not to rotate relative to the rotation of the shaft 3 are provided. The swash plate 20 may be one in which the swash plate can be tilted so as to change the tilt angle. The shoe holder 8 presses the shoe 7 in the axial direction with the pressing force of the spring 25 through the ring 22, the pin 24 and the barrel holder 9. The brake device 10 includes an annular friction plate 15 that rotates integrally with the cylinder barrel 6 on the outer periphery of the cylinder barrel 6 and is movably fitted in the axial direction of the cylinder barrel 6. 6, which can move in the axial direction of the brake 6, presses the friction plate 15 against the casings 1, 2 to brake the rotation of the friction plate 15 integral with the cylinder barrel 6, and the casing presses the brake piston 11 against the friction plate 15. And a plurality of compression coil springs 12 arranged between the brake piston 11 and the brake piston 11.
[0009]
In the embodiment of the present invention, a plurality of compression coil springs 12 are inserted into a plurality of holes 14 provided in an annular cage 13 as shown in FIG. 2 which is a sectional view taken along the line II-II in FIG. The annular cage 13 is fitted into one annular groove 16 provided in the casing. With such a configuration, an inexpensive compression coil spring 12 can be used as the spring, and the plurality of compression coil springs 12 are inserted into the plurality of holes 14 provided in the annular cage 13 so that the compression coil springs 12 do not interfere with each other. Since the annular cage 13 is fitted into the annular groove 16 provided in the lid 2 of the casing, it is only necessary to provide one annular groove 16 in the casings 1 and 2. And the annular cage 13 can be assembled together, and it is not necessary to pay close attention to prevent the compression coil spring 12 from falling apart during assembly, and the assembly of the spring is facilitated. The annular groove 16 provided in the lid 1 of the casing can be processed at low cost, and the assembly of the compression coil spring is facilitated.
[0010]
As shown in FIG. 3 in which a part of the annular cage 13 of FIG. 2 is enlarged, the plurality of holes 14 of the annular cage 13 are formed by eccentric holes or elliptical holes having an inner diameter slightly larger than the compression coil spring 12. As shown in a state in which the compression coil spring 12 of FIG. 3 is fitted, a small gap is formed between the hole 14 and the compression coil spring 12 in the circumferential direction of the annular cage 13, and the compression coil spring 12 is When the friction plate 15 is pushed via the brake piston 11 to brake the rotation of the friction plate 15 integral with the cylinder barrel 6, an abnormal force applied to the compression coil spring 12 is released. Further, a part of the inner wall of the plurality of holes 14 (may be a part of the outer wall) is cut out to form a presser lever 17 having elasticity for pressing the compression coil spring 12, The compression coil spring 12 can be easily inserted, and the compression coil spring 12 does not fall after assembly. The annular cage 13 may be shallow, and the annular groove 16 provided in the lid 1 of the casing can be processed at low cost. It was.
[0011]
As shown in FIG. 2, a rotation prevention protrusion 18 extending inward is provided on a part of the annular cage 13, and is fitted into a key groove 19 provided on the lid 1 of the casing to form a simple detent. The annular cage 13 can be integrally formed of metal or synthetic resin and can be made cheaper. Reference numeral 23 denotes a seal groove into which the oil seal 26 is inserted. A port 28 communicates with a hydraulic source (not shown), and a plurality of pistons 4 inserted into the cylinder barrel 6 so as to be axially slidable through an oil passage (not shown) by an operation valve (not shown) provided on the lid 1 of the casing. Pressure oil is guided to the hole, and the piston 4 is operated. A working chamber having a pressure receiving surface of the brake piston 11 defined by two oil seals 19 through which pressure oil is guided to the oil passage 27 through an operation valve (not shown) provided in the port 28 and the casing lid 1. When the pressure oil is guided to the working chamber 21 by an operation valve (not shown), the brake piston 11 pushes the compression coil spring 12 to release the friction plate 15 and release the brake. When the pressure oil in the working chamber 21 is communicated with a drain (not shown) by an operation valve (not shown), the compression coil spring 12 presses the brake piston 11 against the friction plate 15 and stops the hydraulic motor.
[0012]
As shown in FIG. 2, it is not necessary to provide the housing holes for the plurality of compression coil springs 12 in the casings 1 and 2 and only one annular groove 16 for inserting the annular retainer 13 may be used. The brake pressure can be adjusted by changing the number and size of the holes, and there is no need to provide different numbers and sizes of holes in the casing as in the prior art.
[Brief description of the drawings]
FIG. 1 shows a brake device for a hydraulic motor according to an embodiment of the present invention.
2 is a cross-sectional view of an essential part taken along line II-II in FIG.
FIG. 3 is an enlarged view of a main part in which a part of the annular cage 13 of FIG. 2 is enlarged.
[Explanation of symbols]
1, 2, Casing 3, Shaft 4, Piston 6, Cylinder barrel 10, Brake device 11, Brake piston 12, Compression coil spring 13, Ring retainer 14, Hole 15, Friction plate 16. ・ Annular groove 16 17. ・ Presser lever 18 ・ ・ Protrusion 19 ・ ・ Key groove 20 ・ ・ Swash plate

Claims (5)

A cylinder barrel supported in a casing so as to be rotatable together with the shaft, and the heads of a plurality of pistons inserted in the cylinder barrel so as to be slidable in the axial direction are slidable and cannot be rotated relative to the rotation of the shaft. A hydraulic motor having a swash plate supported in the casing, an annular friction plate fitted integrally with an outer periphery of the cylinder barrel so as to rotate integrally with the cylinder barrel and move in the axial direction of the cylinder barrel, and the casing A brake piston that is arranged in the cylinder barrel and is movable in the axial direction of the cylinder barrel and presses the friction plate against the casing to brake the rotation of the friction plate integral with the cylinder barrel, and the brake piston is pressed against the friction plate A brake device having a spring disposed between the casing and the brake piston,
The spring is composed of a plurality of compression coil springs, the compression coil springs are inserted into a plurality of holes provided in an annular cage, and the annular cage is fitted into an annular groove provided in a casing,
The plurality of holes of the annular cage are formed as eccentric holes or elliptical holes having an inner diameter that is slightly larger than the compression coil spring, and a part of the inner or outer wall of the plurality of holes is cut out. A brake device for a hydraulic motor. 2. The brake device for a hydraulic motor according to claim 1 , wherein a part of the wall of the notched hole has elasticity, and the annular cage is fitted in a shallow annular groove provided in a lid of the casing. . 3. The brake device for a hydraulic motor according to claim 2 , wherein a projection is provided on a part of the annular cage, and the projection is fitted into a key groove provided on a lid of the casing. The brake device for a hydraulic motor according to any one of claims 1 to 3 , wherein the annular cage is integrally formed of metal or synthetic resin. The brake device for a hydraulic motor according to any one of claims 1 to 4 , wherein the swash plate supported in the casing is capable of tilting so as to change an inclination angle.

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