The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.

The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.

Date of Patent:
Dec. 24, 1991

Filed:

Dec. 06, 1990
Applicant:
Inventors:

Kenji Hattori, Tochigi, JP;

Jiro Suzuki, Tochigi, JP;

Kazutoshi Tashima, Tochigi, JP;

Attorney:
Primary Examiner:
Int. Cl.
CPC ...
G01M / ;
U.S. Cl.
CPC ...
731181 ; 340453 ;
Abstract

An apparatus for diagnosing a fault of a hydraulic pressure source, including a fluid tank, a pump for pumping up fluid from the fluid tank, an accumulator for accumulating the fluid pumped up by the pump, a pressure detector for detecting a pressure of the fluid in the accumulator and generating an output signal, a pump drive or motor responsive to the output signal for driving the pump, and an electromagnetic valve of normally closed type interposed either in a flow path between the accumulator and a hydraulic pressure instrument or in a flow path between the tank and the hydraulic pressure instrument. This apparatus comprises an excitation signal generator for generating an excitation signal which excites the electromagnetic valve for a predetermined period of time, and a control unit for determing an anomaly on the basis of the output signal from the pressure detector. If any fault exists in the hydraulic pressure source, fall and rise of the hydraulic pressure is not effected normally. The control unit determines whether the variation of the hydraulic pressure is normal or abnormal on the basis of the output signal from the pressure detector.


Find Patent Forward Citations

Loading…