Title:
油圧システム
Document Type and Number:
Japanese Patent JP6856065
Kind Code:
B2
Abstract:
Provided is a hydraulic system with which an operator can safely perform work during an emergency operation even in the event that an electromagnetic proportional valve itself has failed. This hydraulic system is provided with a hydraulic pump, a control valve, and a pilot pressure supply unit. The pilot pressure supply unit has: an electromagnetic proportional valve that has a detent-type emergency manual operation function with which a pilot oil passage can be opened manually and generates pilot pressure for a control valve; a controller that controls the degree of opening of the electromagnetic proportional valve in accordance with the operation of an operation lever; and a pilot pressure switching unit that switches the oil pressure state of the pilot pressure supply unit between an on-loading state and an unloading state. The pilot pressure switching unit performs control to implement the unloading state when the electromagnetic proportional valve is being opened manually and performs control to implement the on-loading state after the electromagnetic proportional valve has been opened manually.
Inventors:
Naoto Kawabuchi
Takashi Yoshida
Naotaka Masuda
Fukumori Yasuhiro
Takashi Yoshida
Naotaka Masuda
Fukumori Yasuhiro
Application Number:
JP2018507440A
Publication Date:
April 07, 2021
Filing Date:
March 24, 2017
Export Citation:
Assignee:
Tadano Co., Ltd.
International Classes:
F15B20/00
Domestic Patent References:
| JP2003184810A | ||||
| JP9310782A | ||||
| JP7127608A |
Attorney, Agent or Firm:
Washeda International Patent Office