Title:
CONSTRUCTION MACHINE
Document Type and Number:
WIPO Patent Application WO/2021/070736
Kind Code:
A1
Abstract:
Provided is a construction machine that can measure a minute leakage flow rate of a unilateral tilt-type variable displacement hydraulic pump. In a state in which communication between a discharge oil passage of the hydraulic pump and a tank is cut off and the tilt of the hydraulic pump is held at a diagnostic tilt set smaller than a standby tilt, a controller measures the discharge pressure of the hydraulic pump while changing the rotation speed of a prime mover, and calculates the leakage flow rate of the hydraulic pump on the basis of the rotation speed of the prime mover and the diagnostic tilt when the discharge pressure of the hydraulic pump reaches a predetermined pressure.
Inventors:
UDAGAWA TSUTOMU (JP)
SAKURAI SHIGEYUKI (JP)
YAMAMOTO JUNJI (JP)
SUZUKI YUKIHITO (JP)
SAKURAI SHIGEYUKI (JP)
YAMAMOTO JUNJI (JP)
SUZUKI YUKIHITO (JP)
Application Number:
PCT/JP2020/037478
Publication Date:
April 15, 2021
Filing Date:
October 01, 2020
Export Citation:
Assignee:
HITACHI CONSTRUCTION MACH CO (JP)
International Classes:
F15B20/00; E02F9/26; F04B51/00
Foreign References:
| JP2019049204A | 2019-03-28 | |||
| JPH10169604A | 1998-06-23 | |||
| JP2000046015A | 2000-02-15 | |||
| JP2013072454A | 2013-04-22 |
Attorney, Agent or Firm:
KAICHI IP (JP)
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