Title:
APPARATUS FOR DIAGNOSING FAILURE OF HYDRAULIC PUMP FOR WORK MACHINE
Document Type and Number:
WIPO Patent Application WO/1998/006946
Kind Code:
A1
Abstract:
An apparatus for diagnosing failure of hydraulic pumps for a work machine, which apparatus is inexpensive and capable of surely specifying a faulty hydraulic pump or pumps. Pressure sensors (61-64) are provided on lines (30, 40) leading to a tank (T) from locations leaving center bypasses of flow control valves (21, 231-234, 451-454, 26) connected to hydraulic pumps (1-6), and respective solenoid directional control valves (51-56) are provided on input circuits of respective regulators (11-16) to permit, when excited, pressure from a pilot pump (7) to be introduced into the regulators (11-16). When a switch (80) commands judgement with all the flow control valves in neutral positions, a signal from a processing device (70) energizes one of the solenoid directional control valves to cause a corresponding hydraulic pump to discharge a fluid at a maximum flow rate. A detected value from an associated pressure sensor at this time is converted into a flow rate and stored, and this sequence is carried out with respect to the respective hydraulic pumps. On the basis of flow rates obtained from every judgement, failure of a specified hydraulic pump or pumps is diagnosed.
Inventors:
TANAKA YASUO (JP)
OCHIAI MASAMI (JP)
YAGYU TAKASHI (JP)
HASHIMOTO AKIRA (JP)
FURUNO YOSHINORI (JP)
WATANABE YUTAKA (JP)
SUGIYAMA YUKIHIKO (JP)
OCHIAI MASAMI (JP)
YAGYU TAKASHI (JP)
HASHIMOTO AKIRA (JP)
FURUNO YOSHINORI (JP)
WATANABE YUTAKA (JP)
SUGIYAMA YUKIHIKO (JP)
Application Number:
PCT/JP1997/002771
Publication Date:
February 19, 1998
Filing Date:
August 07, 1997
Export Citation:
Assignee:
HITACHI CONSTRUCTION MACHINERY (JP)
TANAKA YASUO (JP)
OCHIAI MASAMI (JP)
YAGYU TAKASHI (JP)
HASHIMOTO AKIRA (JP)
FURUNO YOSHINORI (JP)
WATANABE YUTAKA (JP)
SUGIYAMA YUKIHIKO (JP)
TANAKA YASUO (JP)
OCHIAI MASAMI (JP)
YAGYU TAKASHI (JP)
HASHIMOTO AKIRA (JP)
FURUNO YOSHINORI (JP)
WATANABE YUTAKA (JP)
SUGIYAMA YUKIHIKO (JP)
International Classes:
E02F9/22; E02F9/26; F04B49/06; F04B51/00; F15B20/00; (IPC1-7): F04B51/00; F15B20/00
Foreign References:
JPS5983812A | 1984-05-15 | |||
JPS6220681A | 1987-01-29 |
Attorney, Agent or Firm:
Take, Kenjiro (6-13 Nishishinbashi 1-chom, Minato-ku Tokyo 105, JP)
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