Title:
HYDRAULIC UNIT AND DIAGNOSIS METHOD OF HYDRAULIC ACTUATOR
Document Type and Number:
Japanese Patent JP2022057405
Kind Code:
A
Abstract:
To provide a hydraulic unit which can simplify a constitution for diagnosing abnormality of a hydraulic cylinder.SOLUTION: A hydraulic unit comprises: a hydraulic pump for supplying a working fluid to a hydraulic actuator; a motor for driving the hydraulic pump; a rotational speed sensor for detecting a rotational speed of the motor; a pressure sensor for detecting the pressure of the working fluid which is discharged by the hydraulic pump; and a control part. In a pressure maintaining step of the hydraulic actuator, flow rate constant control for maintaining a flow rate of the working fluid discharged from the hydraulic pump to be constant, and pressure constant control for maintaining the pressure of the working fluid discharged from the hydraulic pump to be constant, are performed. In the case that a start signal of the pressure-maintaining step is inputted during the control of the motor, when a pressure (P) of the working fluid detected by the pressure sensor exceeds a prescribed reference pressure (Pt) during the flow rate constant control, or when a flow rate (Q) of the working fluid discharged from the hydraulic pump exceeds a prescribed reference flow rate (Qt) during the pressure constant control, the control part determines that abnormality has occurred in the hydraulic actuator.SELECTED DRAWING: Figure 4
Inventors:
IKEMOTO TAKAMASA
KAWADA KENICHI
KAWADA KENICHI
Application Number:
JP2020165645A
Publication Date:
April 11, 2022
Filing Date:
September 30, 2020
Export Citation:
Assignee:
DAIKIN IND LTD
International Classes:
F15B20/00; F15B1/26
Attorney, Agent or Firm:
Takuji Yamada
Etsuko Isoe
Toshiyuki Yamazaki
Etsuko Isoe
Toshiyuki Yamazaki