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.
Patent No.:
Date of Patent:
Aug. 31, 1999
Filed:
Dec. 22, 1997
Applicant:
Inventors:
Hideo Konishi, Tokyo, JP;
Makoto Samejima, Tokyo, JP;
Assignee:
Shin Caterpillar Mitsubishi Ltd., Tokyo, JP;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
F04B / ; F16D / ;
U.S. Cl.
CPC ...
4172221 ; 60430 ; 60449 ;
Abstract
A hydraulic pump control system is shown that can control the absorbing torque of a hydraulic pump with respect to the engine power for driving the hydraulic pump in a well-balanced manner, and reduce a deviation of an actual revolution number from a target revolution number of the engine. A torque of hydraulic pumps during operation is estimated from a pump pressure and first and second line pressures. Based on the estimated torque, an output torque of the hydraulic pumps is controlled so that an error between a target revolution number and an actual revolution number of the engine becomes null.