JP2007009801A - Hydraulic motor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To miniaturize a hydraulic motor by providing a spring for a brake pressing a brake piston against a flange at an outside of a swash plate and a rotation stopping pin of the brake piston on a same circumference. <P>SOLUTION: A plurality of spring holes 21 in which springs 9 pressing annular brake pistons 7 against the flange 13 are inserted are provided on a circumference outside of a swash plate 4, and a pin hole 22 in which the rotation stopping pin 8 is inserted is provided on the same circumference as the spring holes 21 on the flange 13. Consequently, an outer shape of the hydraulic pump can be downsized. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a hydraulic motor for driving a turning device for a construction machine, and more particularly to an improvement in a hydraulic motor for realizing a reduction in size and weight.

2. Description of the Related Art Conventionally, hydraulic motors used for construction machines and the like are provided with a so-called negative brake device.
For example, as shown in FIG. 2, the hydraulic motor 10 is supported by a casing 1 integrated with a flange 13 and a bolt 15, and bearings 16 and 17 provided in the casing 1 in the casing 1, and around an axis thereof. A rotating shaft 2 that rotates and a cylinder block 3 that is fitted to the rotating shaft 2 and rotates together are provided. The rotating shaft 2 protrudes outside from the flange 13 side, and is connected to, for example, a turning mechanism (not shown) of a turntable via a gear (not shown). A plurality of cylinders 18 are formed in the cylinder block 3 so that pistons 14 can enter and exit in the axial direction, and the ends of the pistons 14 are in contact with a swash plate 4 provided inside the flange 13 to rotate the cylinder block 3. It is provided to go in and out.

By supplying hydraulic pressure from a hydraulic port (not shown), pressure is supplied to the cylinder 18, the piston 14 is pressed against the swash plate 4 side to change it into rotational force, the cylinder block 3 is rotated, and the rotary shaft 2 is rotated. Acts as a hydraulic motor. The details are the same as those of a general swash plate type hydraulic motor, and the description thereof is omitted.
Here, the hydraulic motor 10 applies a mechanical brake by the force of the spring 9 when stopped, and pushes the annular brake piston 7 toward the spring 9 by the oil pressure of the annular oil chamber 12 when the hydraulic motor is operated to apply the mechanical brake. Has a system to cancel. In order to apply this mechanical brake, a spring 9 for displacing the annular brake piston 7 toward the movable brake disk 5 in the axial direction by a spring force is disposed so as to contact the end face of the annular brake piston 7. A plurality of the springs 9 are arranged annularly over the entire circumference of the annular brake piston 7 and are fixed by a retainer 11. Thereby, when the external force is applied in a state where the brake is applied and the external force exceeds the braking force and the movable brake disk 5 is dragged and rotated, the rotational force is applied to the annular brake piston 7 by the frictional force. A hole (not shown) is provided in each of the flange 13 and the annular brake piston 7 so that the annular brake piston 7 does not rotate even when this rotational force is applied, and a detent pin 8 is inserted into the hole (for example, Patent Document 1).

JP 2005-16694 A

However, in the hydraulic motor described in Patent Document 1, since the rotation prevention pin is disposed on the outer periphery of the spring, the outer diameter of the annular brake piston and the casing increases. As a result, the hydraulic motor becomes large and expensive.
The present invention has been made to solve the above problems, and a plurality of spring holes for inserting a spring for pressing the annular brake piston are provided on the flange on the circumference outside the swash plate. By providing a pin hole for inserting an anti-rotation pin for the annular brake piston on the same circumference as the plurality of spring holes, it is not necessary to arrange an anti-rotation pin for the annular brake piston outside the spring. An object of the present invention is to provide a hydraulic motor capable of reducing the dimension in the outer diameter direction.

To achieve the above object, the present invention provides a casing,
A flange engaged with the casing;
A rotating shaft that is supported by the casing and rotates about its axial gland;
A cylinder block fitted to the rotating shaft and rotating together;
A movable brake disc supported in an axially outer circumferential groove on the outer periphery of the cylinder block so as to be fixed in the rotational direction and movable in the axial direction;
A fixed brake disc provided on the inner periphery of the casing and fixed to the casing and the cylinder block by pressure contact in the axial direction of the movable brake disc;
An annular brake piston which is annularly provided on the inner periphery of the casing and is movable in the axial direction, and the movable brake disc is movable in the axial direction;
A spring provided between the annular brake piston and the flange for urging the annular brake piston toward the movable brake disc;
In the hydraulic motor with
A hole provided in the flange outside the swash plate for inserting the spring;
A pin hole which is provided on the same circumference of the hole and into which a pin for preventing rotation of the annular brake piston is inserted;
It is characterized by having.

The present invention relates to a hydraulic motor in which a hole provided on the flange outside the swash plate for inserting the spring and a pin provided on the same circumference of the hole for inserting the brake piston detent pin By having the hole, it is not necessary to dispose the brake piston detent pin on the outside of the spring, so that the dimension of the hydraulic motor in the outer diameter direction can be reduced. Accordingly, the size of the hydraulic motor can be reduced, the handling can be facilitated, and the space for assembling the hydraulic motor to the turning device can be reduced.
Further, since it is not necessary to integrally connect a plurality of springs to the plate, the structure becomes simple, and there are few failures and maintenance is easy.

Embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a longitudinal sectional view of a hydraulic motor 20 showing an embodiment of the present invention. In FIG. 1, the same components as those in FIG. . In the hydraulic motor 20 of FIG. 1, a plurality of spring holes 21 for inserting the springs 9 are provided on the flange 13 on the circumference outside the swash plate 11. The flange 13 is provided with a pin hole 22 for inserting the detent pin 8 on the same circumference as the plurality of spring holes (holes) 21.
As a result, it is not necessary to dispose the detent pin 8 outside the spring 9, so that the dimension of the hydraulic motor 20 in the outer diameter direction can be reduced. As a result, the hydraulic motor 20 can be reduced in size, handled easily, and a space for assembling the hydraulic motor 20 to the turning device can be reduced.
Further, since it is not necessary to integrally connect the spring 9 to a retainer (not shown), the structure becomes simple, and there are few failures and maintenance is easy.

It is a longitudinal cross-sectional view of the hydraulic motor which shows embodiment of this invention. It is a conventional hydraulic motor wire sectional view.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Casing 10 Hydraulic motor 2 Rotating shaft 11 Retainer 3 Cylinder block 12 Annular oil chamber 4 Swash plate 13 Flange 5 Movable brake disc 14 Piston 6 Fixed brake disc 18 Cylinder 7 Annular brake piston 20 Hydraulic motor 8 Non-rotating pin 21 Spring hole 9 Spring 22 Pin hole

Claims (1)

A casing,
A flange engaged with the casing;
A rotating shaft that is supported by the casing and the flange and rotates about its axial gland;
A cylinder block fitted to the rotating shaft and rotating together;
A movable brake disc fixed to the axial outer circumferential groove on the outer circumference of the cylinder block and supported so as to be movable in the axial direction;
A fixed-side brake disc that is provided on the inner periphery of the casing and is fixed to the casing and the cylinder block by pressure contact in the axial direction of the movable-side brake disc;
An annular brake piston which is annularly provided on the inner periphery of the casing and is movable in the axial direction, and the movable brake disc is movable in the axial direction;
A spring provided between the annular brake piston and the flange for urging the annular brake piston toward the movable brake disc;
In the hydraulic motor with
A hole provided in the flange outside the swash plate for inserting the spring;
A pin hole which is provided on the same circumference of the hole and into which a pin for preventing rotation of the annular brake piston is inserted;
A hydraulic motor comprising:

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