Title:
HYDRAULIC SYSTEM FOR WORK MACHINE, AND WORK MACHINE
Document Type and Number:
WIPO Patent Application WO/2023/132175
Kind Code:
A1
Abstract:
The present invention suppresses a reduction in the response speed of an electromagnetic proportional valve (45) at low temperatures. This hydraulic system (S) for a work machine (1) comprises: a hydraulic actuator (AC); a direction switching valve (41); an electromagnetic proportional valve (45); a control device (70) that controls current supplied to the electromagnetic proportional valve (45); an operation member (75) for a worker to operate the hydraulic actuator (AC); and a permission operating tool (77) that can switch between a permitting operation for permitting driving of the hydraulic actuator (AC) and a non-permitting operation for not permitting driving, wherein, when the permission operating tool (77) is performing the non-permitting operation and the temperature of hydraulic fluid is below a prescribed temperature, the control device (70) supplies, to the electromagnetic proportional valve (45), a first standby current of a first current value (Ia) defined in a range where a switching position of the direction switching valve (41) is not switched.
Inventors:
HORII HIROSHI (JP)
MORI HIROYA (JP)
MORI HIROYA (JP)
Application Number:
PCT/JP2022/045018
Publication Date:
July 13, 2023
Filing Date:
December 07, 2022
Export Citation:
Assignee:
KUBOTA KK (JP)
International Classes:
F15B21/045; E02F9/20
Foreign References:
| JPH0579503A | 1993-03-30 | |||
| JP2009509837A | 2009-03-12 | |||
| JP2020159465A | 2020-10-01 |
Attorney, Agent or Firm:
YASUDA & OKAMOTO PATENT ATTORNEYS (JP)
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