Title:
HYDRAULIC DRIVE SYSTEM
Document Type and Number:
WIPO Patent Application WO/2014/061407
Kind Code:
A1
Abstract:
A hydraulic oil flow path has a first flow path and a second flow path. The first flow path connects a first pump port and a first chamber of a hydraulic cylinder. The second flow path connects a second pump port and a second chamber of the hydraulic cylinder. The hydraulic oil flow path configures a closed circuit between a hydraulic pump and the hydraulic cylinder. A bleed-off flow path is a flow path for bleeding off some of the hydraulic oil from the second flow path. When the amount that an operation member for lowering a work machine is operated is smaller than a prescribed operation amount, a control valve connects the second flow path to the bleed-off flow path, via an aperture, such that the hydraulic pressure of the second flow path is suppressed to a pressure lower than the relief pressure. The prescribed operation amount is no greater than the maximum operation amount for the operation member for lowering the work machine.
Inventors:
AKIYAMA TERUO (JP)
IIDA NOBORU (JP)
SAITO KOJI (JP)
WATANABE TAKAYUKI (JP)
SASANO KENJI (JP)
IIDA NOBORU (JP)
SAITO KOJI (JP)
WATANABE TAKAYUKI (JP)
SASANO KENJI (JP)
Application Number:
PCT/JP2013/075792
Publication Date:
April 24, 2014
Filing Date:
September 25, 2013
Export Citation:
Assignee:
KOMATSU MFG CO LTD (JP)
International Classes:
F15B11/02; E02F9/22; F15B11/08
Foreign References:
| JP2001012406A | 2001-01-16 | |||
| JPH10331803A | 1998-12-15 | |||
| JPS49125764A | 1974-12-02 | |||
| JPS55149332U | 1980-10-27 | |||
| JPH01280132A | 1989-11-10 |
Attorney, Agent or Firm:
Shinjyu Global IP (JP)
fresh green -- a global IP patent business corporation (JP)
fresh green -- a global IP patent business corporation (JP)
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