Title:
WORK MACHINE HYDRAULIC CIRCUIT
Document Type and Number:
WIPO Patent Application WO/2017/145658
Kind Code:
A1
Abstract:
Provided is a work machine hydraulic circuit by which good turning operation feel is obtained. This work machine hydraulic circuit is provided with: a prime mover, the rotation speed of which is determined on the basis of an operation instruction; a variable capacity hydraulic pump driven by the prime mover; a turning motor driven by the oil discharged from the variable capacity hydraulic pump; and an open center-type control valve for controlling the pressure oil supplied from the variable capacity hydraulic pump to the turning motor and, in an initial position, for performing control so that the oil discharged from the variable capacity hydraulic pump is returned to a tank. The work machine hydraulic circuit is characterized: in being provided with a rotation speed signal-generating unit for generating a rotation speed signal that represents the rotation speed of the prime mover and a flow rate adjusting valve for adjusting the flow rate of the pressure oil guided from the variable capacity hydraulic pump to the control valve; and in the flow rate adjusting valve making the pressure difference across the control valve to be a value corresponding to the rotation speed of the prime mover on the basis of the rotation speed signal output by the rotation speed signal-generating unit.
Inventors:
OOKI TAKATOSHI (JP)
MIYAZAKI TADASHI (JP)
MIYAZAKI TADASHI (JP)
Application Number:
PCT/JP2017/003245
Publication Date:
August 31, 2017
Filing Date:
January 30, 2017
Export Citation:
Assignee:
HITACHI CONSTRUCTION MACH CO (JP)
HITACHI SUMITOMO HEAVY IND CONSTRUCTION CRANE CO LTD (JP)
HITACHI SUMITOMO HEAVY IND CONSTRUCTION CRANE CO LTD (JP)
International Classes:
F15B11/05; B66C13/20; B66C23/86
Foreign References:
| JPH11158939A | 1999-06-15 | |||
| JP2005265016A | 2005-09-29 |
Attorney, Agent or Firm:
THE PATENT BODY CORPORATE TAKEWA INTERNATIONAL PATENT OFFICE (JP)
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