Login| Sign Up| Help| Contact|

Patent Searching and Data


Title:
HYDRAULIC CIRCUIT FOR CONSTRUCTION MACHINERY AND CONTROL DEVICE FOR SAME
Document Type and Number:
WIPO Patent Application WO/2014/024521
Kind Code:
A1
Abstract:
The circuit has: a directional control valve group including a plurality of directional control valves arranged in tandem on a center bypass passage; and a bleed-off valve arranged on the center bypass passage downstream from the directional control valve group. The directional control valves are provided with a first inner passage for outflow of hydraulic fluid to the center bypass passage, and a second inner passage for supplying hydraulic fluid to a hydraulic actuator. Hydraulic fluid discharged from a pump outflows through the first inner passage to the center bypass passage at a point downstream with respect to the directional control valve, whereby the center bypass and the first inner passage form a parallel passage. The second inner passage supplies hydraulic fluid from the center bypass passage to a cylinder port through a bypass passage and/or opening in a spool.

Inventors:
HASHIMOTO HIROFUMI (JP)
Application Number:
PCT/JP2013/060962
Publication Date:
February 13, 2014
Filing Date:
April 11, 2013
Export Citation:
Click for automatic bibliography generation   Help
Assignee:
SUMITOMO SHI CONSTR MACH CO (JP)
International Classes:
F15B11/00; E02F9/22
Foreign References:
JPH1018359A1998-01-20
JPH11230375A1999-08-27
JPH10147959A1998-06-02
JP2000009102A2000-01-11
JPH11107328A1999-04-20
JPH03219102A1991-09-26
JP2009228872A2009-10-08
JPH11257302A1999-09-21
Other References:
See also references of EP 2884117A4
Attorney, Agent or Firm:
ITOH, Tadashige et al. (JP)
Tadashige Ito (JP)
Download PDF: