JPH0160004U

JPH0160004U -

Info

Publication number: JPH0160004U
Application number: JP15539387U
Authority: JP
Priority date: 1987-10-09
Filing date: 1987-10-09
Publication date: 1989-04-17

Description

[Brief explanation of the drawing]

第１図は本考案の第１の実施例を示す油圧回路
図、第２図は同じく第２の実施例を示す油圧回路
図、第３図は同じく第３の実施例を示す油圧回路
図、第４図は従来技術を示す油圧回路図、第５図
は他の従来技術を示す油圧回路図である。１……油圧モータ、１Ａ……容量可変部、３…
…高圧選択弁、４……アクチユエータ、１０……
パイロツト油圧源、３１，５１……容量制御弁、
３６，４７……選択切換弁、４１，５３……パイ
ロツト圧切換弁、４８……減圧弁。 FIG. 1 is a hydraulic circuit diagram showing a first embodiment of the present invention, FIG. 2 is a hydraulic circuit diagram also showing a second embodiment, and FIG. 3 is a hydraulic circuit diagram showing a third embodiment. FIG. 4 is a hydraulic circuit diagram showing a prior art, and FIG. 5 is a hydraulic circuit diagram showing another prior art. 1...Hydraulic motor, 1A...Variable capacity section, 3...
...High pressure selection valve, 4... Actuator, 10...
Pilot hydraulic power source, 31, 51... capacity control valve,
36, 47... Selection switching valve, 41, 53... Pilot pressure switching valve, 48... Pressure reducing valve.

Claims

[Claims for Utility Model Registration] (1) A displacement control device for a hydraulic motor comprising a variable displacement hydraulic motor having a variable displacement section and a variable displacement actuator for driving the variable displacement section of the hydraulic motor, A self-pressure control that operates the variable capacity actuator according to the magnitude of the motor self-pressure supplied to the hydraulic motor, a large-capacity control that operates the variable-capacity actuator regardless of the magnitude of the motor self-pressure, and a large-capacity control that maintains a constant large capacity and a small-capacity control. A hydraulic pilot-type capacity control valve that can be controlled in three types: constant small capacity control and self-pressure control by directly or indirectly switching the pilot pressure supplied to and discharged from the capacity control valve. 1. A displacement control device for a hydraulic motor, comprising a selection switching valve that selectively switches between three positions: control, large capacity control, and small capacity control. (2) The scope of the utility model registration claim, which is configured to directly supply pilot pressure from an external hydraulic source to the capacity control valve by switching the selection switching valve to a large capacity control position or a small capacity control position.
A displacement control device for a hydraulic motor as described in (1). (3) It has a pilot pressure switching valve that switches between three positions depending on the pilot pressure from an external hydraulic source and the reduced pilot pressure, and switches the selection switching valve to a large capacity control position or a small capacity control position. Accordingly, the hydraulic motor according to claim (1), which is registered as a utility model, is configured to directly supply pilot pressure or reduced pressure pilot pressure from an external hydraulic source to the displacement control valve via the pilot pressure switching valve. Capacity control device. (4) It has a pilot pressure switching valve that switches between three positions depending on the pilot pressure from an external hydraulic source and the pilot pressure that is reduced from the pilot pressure, and by switching the selection switching valve to each switching position, the pilot pressure can be changed. The hydraulic pressure according to claim (1) of the utility model registration, which is configured to supply and discharge motor self-pressure or pilot pressure to and from the capacity control valve via a switching valve, and to control the capacity control valve in three types. Motor capacity control device.