JPH0579004U - Hydraulic circuit device for releasing mechanical brake of hydraulic motor - Google Patents

Abstract

(57) [Abstract] [Object] To provide a hydraulic circuit device for mechanical brake release, which can be inexpensively constructed and has excellent durability of a brake member. [Structure] To a brake member 16 of a hydraulic motor 1 having a mechanical brake. The brake circuit 13 is provided so that the hydraulic pressure for releasing the brake operation is supplied from the circuit 11a in front of the directional control valve 10 provided in the hydraulic pressure supply circuit 11 from the hydraulic pump 12 to the hydraulic motor. The pressure generation position 10c for generating the brake release pressure is provided in the circuit in the front of the circuit during the switching between the flow position 10b and the flow cutoff position 10a. [Effect] When the hydraulic motor rotates, the brake is already released. Since the brake member is not worn out and the brake release pressure can be secured without installing special equipment, it can be manufactured at low cost.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a hydraulic circuit device that releases a mechanical brake provided in a rotary device of various industrial machines, for example, a hydraulic motor that drives a rotary part of a crane or a power shovel.

[0002]

[Prior Art]

 Conventionally, as a mechanical brake of a hydraulic motor, a friction disc type as shown in FIG. 1 is known, and a disc-shaped brake plate b that rotates together with a rotating body a of a cylinder block that is rotated by hydraulic pressure. In addition, the casing c of the hydraulic motor m is provided with a mating plate d that makes frictional contact with the brake plate b, and when the mating plate d is pushed by the spring f via the annular piston e, the rotation of the rotating body a is prevented. The rotation shaft a that is stopped and spline-engaged with the rotating body a is braked so as not to rotate. The pressure from the pilot port h acts on the stepped portion of the piston e. When this pressure acts, the piston e retracts against the spring f, and the braking of the rotating shaft g is released. To be done.

Further, as shown in FIG. 2, a square portion i is formed at the shaft end of a rotary shaft g of a hydraulic motor m, and a square outer periphery protruding and retracting from a square hole j provided in a casing c is formed in the square portion i. There is also proposed a mechanical brake in which a square hole 1 of a piston k is fitted to brake the rotation shaft g so that it cannot rotate. Also in this case, when the pressure introduced from the pilot port h is applied to the piston k, the piston k retracts against the spring f, and the braking of the rotating shaft g is released.

[0004]

[Problems to be solved by the device]

 In order to release the mechanical brake as described above, pressure is required in the pilot port h. Therefore, conventionally, the pressure is guided to the pilot port h from a separately provided hydraulic source, or as shown in FIG. A shuttle valve p is installed between the hydraulic motor m and the direction switching valve o of the hydraulic pressure supply circuit n to ensure the high pressure selected from the circuit n as the brake release pressure. Providing a separate hydraulic source for brake release has the disadvantage that the hydraulic system is expensive. Further, in the case of FIG. 3, when the switching valve o is switched from the neutral position to the switching position q or r, the hydraulic motor m is braked immediately after the switching so that either the A or B port of the hydraulic motor m is switched. A pressure commensurate with the brake pressure is generated at this point, and this pressure causes the brake to be released, but at the moment this brake is released, the hydraulic motor m tries to rotate with the brake applied, so In the case of the brake member, for example, in FIG. 1, slippage occurs between the brake plate b and the mating plate d, the wear of both parts is promoted, and the service life of the brake member is shortened. Further, although not shown, a check valve is interposed between the pump and the direction switching valve in the hydraulic pressure supply circuit from the pump to the hydraulic motor m, and the oil is generated from the pump to the hydraulic motor m by the check valve. It may be possible to use the passage resistance for brake release pressure, but this passage resistance causes pressure and energy loss, which causes the hydraulic oil to deteriorate due to heat generation, the cost increase due to the use of a check valve, and the directional control valve. Even when neutral, the brake release pressure is generated if there is an amount of oil from the pump, which causes a problem that the hydraulic motor is not braked, which is not preferable. An object of the present invention is to provide a hydraulic circuit device for mechanical break release having good durability which can be constructed at a low cost without such inconvenience.

[0005]

[Means for Solving the Problems]

 According to the present invention, a rotating member that is rotated by the hydraulic pressure of a hydraulic motor or a rotating shaft that is connected to the rotating member is provided with a brake member such as a friction member or an engaging member that is disengaged by the hydraulic pressure to apply a brake to the rotating shaft. The brake circuit is provided so that the hydraulic pressure for releasing the brake operation to the brake member is supplied from the circuit in front of the directional control valve provided in the hydraulic pressure supply circuit from the hydraulic pump to the hydraulic motor. By providing a pressure generating position for generating a brake release pressure in the circuit in front of the directional control valve in the middle of switching between the flow position of the directional control valve to the hydraulic pump and the flow cut-off position, the above object can be achieved. I chose

[0006]

[Action]

 When the directional control valve is in the flow cutoff position, the hydraulic pressure for releasing the brake operation is not generated in the brake circuit, so the brake member of the hydraulic motor performs the brake operation, and the rotating body and rotary shaft of the hydraulic motor are braked. Be done. When attempting to rotate the hydraulic motor by switching the directional control valve of the hydraulic pressure supply circuit to the distribution position, the pressure generation position enters immediately before the directional control valve switches to the distribution position. A brake release pressure is generated, and this pressure acts on the brake member of the hydraulic motor from the brake circuit to release the brake. Therefore, when the directional control valve is switched to the distribution position, the brake is already released, so that the brake components are not damaged and the directional control valve is used, so that no special component is required.

[0007]

【Example】

 An embodiment of the present invention will be described with reference to the drawings. In FIG. 4, reference numeral 1 is a hydraulic motor, and inside a casing 2 thereof, a rotating body 3 composed of a cylinder block rotated by hydraulic pressure and a spline engagement therewith. The rotating shaft 4 is provided. A brake plate 5 made of an annular friction member that constitutes a brake member 16 is attached to the outer periphery of the rotating body 3, and opposite plates 6 are provided so as to face both sides of the brake plate 5. The mating plate 6 is brought into frictional contact with the brake plate 5 by the piston 8 pushed by the spring 7, and brakes the rotating body 3 and the rotating shaft 4. The mating plate 6, the spring 7 and the piston 8 also constitute the brake member 16. When brake release pressure is introduced to the pilot port 9, the piston 8 moves backward against the spring 7, the frictional contact between the brake plate 5 and the mating plate 6 is released, and the rotating body 3 and the rotating shaft 4 rotate. . Further, the hydraulic motor 1 is rotated by hydraulic pressure from a hydraulic pump 12 supplied by a hydraulic pressure supply circuit 11 having a direction switching valve 10 having a flow cutoff position (neutral position) 10a and a flow position (switching position) 10b.

Although such a structure is no different from the conventional one, in the case of the present invention, the direction switching valve 10 of the hydraulic pressure supply circuit 11 is provided to the piston 8 constituting the brake member via the pilot port 9 and the brake circuit 13. The hydraulic pressure is introduced from a circuit in front of the directional switching valve 10, that is, a circuit 11a connecting the directional switching valve 10 and the hydraulic pump 12, so that the circuit 11a in front of the directional switching valve 10 is in the middle of switching between the flow cut-off position 10a and the flow position 10b. A pressure generating position 10c for generating a brake release pressure is provided at the position. When the switching valve 10 is operated from the flow shut-off position 10a to the flow position 10b in order to rotate the hydraulic motor 1, the pressure generating position 10c temporarily enters during the switching, and the brake is released to the front circuit 11a. Pressure is generated and the piston 8 operates to release the brake. In order to generate the pressure at the pressure generating position 10c, in the example of FIG. 4, the throttle 14 for restricting the flow rate from the circuit 11a to the hydraulic motor 1 is provided to generate the necessary brake release pressure. As described above, the flow rate from the pump 12 may be blocked so that the flow rate does not flow to the hydraulic motor 1 and the tank 15.

[0009]

[Effect of the device]

 As described above, according to the present invention, a brake circuit for guiding the release pressure from the front of the directional control valve of the hydraulic pressure supply circuit of the hydraulic motor to the brake member is provided, and the directional control valve is provided in the middle of the flow position and the flow cutoff position. Since the pressure generation position is provided, the brake is already released when the hydraulic motor rotates, so the brake member does not wear, and the brake release pressure can be secured without the need for special equipment, so it can be manufactured at low cost. It has the effect of being able to do so.

[Brief description of drawings]

FIG. 1 is a cutaway side view of a conventional hydraulic motor having a mechanical brake.

FIG. 2 is a cutaway side view of a hydraulic motor having another conventional mechanical brake.

FIG. 3 is a diagram of a hydraulic circuit for obtaining a conventional brake release pressure.

FIG. 4 is a cutaway side view of an embodiment of the present invention.

FIG. 5 is an explanatory diagram of another embodiment of the present invention.

[Explanation of symbols]

1 Hydraulic motor 3 Rotor 4
Rotating shaft 10 Directional switching valve 10a Flow shut-off position 10
b Distribution position 10c Pressure generation position 11 Hydraulic pressure supply circuit 1
1a Front circuit 12 Hydraulic pump 13 Brake circuit 1
5 Tank 16 Brake member

Claims (2)

[Scope of utility model registration request] 1. A braking member, such as a friction member or an engaging member that is disengaged by hydraulic pressure, is provided on a rotary body that is rotated by the hydraulic pressure of a hydraulic motor or a rotary shaft that is connected to the rotary body so as to apply a brake to the rotary shaft. In the above, a brake circuit is provided so that the hydraulic pressure for releasing the brake operation to the brake member is supplied from a circuit in front of the direction switching valve provided in the hydraulic pressure supply circuit from the hydraulic pump to the hydraulic motor. A mechanical brake release of a hydraulic motor, characterized in that a pressure generation position for generating a brake release pressure is provided in the front circuit in the middle of switching between the flow position of the directional control valve to the hydraulic pump and the flow cutoff position. Hydraulic circuit device. 2. The hydraulic motor according to claim 1, wherein the pressure generating position is constituted by a throttle for reducing a flow rate from the hydraulic pump to the hydraulic motor or a block for stopping the outflow to the hydraulic motor and the tank. Hydraulic circuit device for mechanical brake release.