Title:
作業機械の油圧制御システム
Document Type and Number:
Japanese Patent JP6574066
Kind Code:
B2
Abstract:
Provided is a work machine hydraulic control system capable of detecting abnormality in a pump output power switching device independently of the abnormality state of the pump output power switching device.A hydraulic control system of a hydraulic excavator is equipped with an accumulator 21 connected to a hydraulic line 25A between a pilot pump 17 and a pilot valve 20, an unloading valve 27 that is a pump output power switching device, a pressure sensor 29 detecting the pressure of the hydraulic fluid supplied to the pilot valve 20, and a controller 30 having a pump output power control section 31 switching the unloading valve 27 in accordance with the pressure detected by the pressure sensor 29. The controller 30 further has an abnormality determination section 32 that computes a command continuation time in a state in which a command output to the unloading valve 27 is not changed. In the case where this command continuation time is not less than a predetermined value, it determines that the unloading valve 27 is abnormal, and outputs the determination result.
Inventors:
Yuichi Ogawa
Hijikata Seiji
Masatoshi Hoshino
Hijikata Seiji
Masatoshi Hoshino
Application Number:
JP2018537547A
Publication Date:
September 11, 2019
Filing Date:
March 27, 2017
Export Citation:
Assignee:
Hitachi Construction Machinery Co., Ltd.
International Classes:
F15B21/14; F15B1/027; F15B11/02; F15B11/028; F15B11/08; F15B20/00
Domestic Patent References:
| JP6323308A | ||||
| JP2058101U |
Foreign References:
| WO2016147283A1 | ||||
| WO2017164370A1 |
Attorney, Agent or Firm:
Kaichi International Patent Office