Title:
HYDRAULIC CONTROL CIRCUIT
Document Type and Number:
Japanese Patent JP3667036
Kind Code:
B2
Abstract:
PROBLEM TO BE SOLVED: To prevent incurring of an energy loss and perform operation with energy saved when a working pressure to an actuator and a pilot pressure to a control valve are supplied.
SOLUTION: A hydraulic control circuit comprises a restrictor 8 to branch a delivery of a pump P to first and second ports 9 and 10; an unload valve 11 connected between a first port and a tank: a relief valve 14 connected to a spot situated downstream from the unload valve; a restriction arranged upper stream from the unload valve; a exhaust passage to communicate a spot, situated upper stream from the relief valve, with a tank; first and second switch means to respectively switch first and second valve groups A and B connected to a second part; and a main pilot passage 22 to guide a pilot pressure to the first switch means through a pressure reducing valve 21 connected to the pump. When, simultaneously with operation of the first switch means, communication between the first switch means and the second port is disconnected and meanwhile, when a given pilot pressure is generated at a main pilot pressure, by restoring the unload valve to a normal stage, the second port and the pump are intercommunicated.
Inventors:
Ogata Akio
Application Number:
JP17115997A
Publication Date:
July 06, 2005
Filing Date:
June 12, 1997
Export Citation:
Assignee:
Kayaba Industry Co., Ltd.
International Classes:
F15B11/00; F15B11/08; (IPC1-7): F15B11/08
Domestic Patent References:
| JP4258513A | ||||
| JP4083908A | ||||
| JP8232907A | ||||
| JP7023793U | ||||
| JP4256695A | ||||
| JP6022602U | ||||
| JP54150277U |
Attorney, Agent or Firm:
Nobuyuki Shima
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