Title:
故障診断装置
Document Type and Number:
Japanese Patent JP6816762
Kind Code:
B2
Abstract:
Provided is a failure diagnosis device capable of surely finding failure of an unload circuit of a hydraulic system. The unload circuit includes a pump oil passage that connects between a hydraulic pump and a direction control valve, a tank oil passage that connects between the direction control valve and a hydraulic tank, a pressure compensating flow control valve interposed between the pump oil passage and the tank oil passage, a pilot operated relief valve interposed between the pump oil passage and the tank oil passage, and an unloading solenoid valve interposed in a vent oil passage of the pilot operated relief valve. The failure diagnosis device includes a pressure sensor that measures a pressure of the pump oil passage, and a controller that receives a pressure signal from the pressure sensor. The controller performs failure diagnosis of the unload circuit based on a differential pressure between a first pump oil passage pressure during unloading and a second pump oil passage pressure during on-loading.
Inventors:
Naoto Kawabuchi
Takashi Yoshida
Fukumori Yasuhiro
Takashi Yoshida
Fukumori Yasuhiro
Application Number:
JP2018507439A
Publication Date:
January 20, 2021
Filing Date:
March 24, 2017
Export Citation:
Assignee:
Tadano Co., Ltd.
International Classes:
F15B20/00
Domestic Patent References:
| JP2011149509A | ||||
| JP62180894A | ||||
| JP11200423A | ||||
| JP2168004A |
Attorney, Agent or Firm:
Washeda International Patent Office