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:
Apr. 23, 2002
Filed:
Jul. 07, 2000
Applicant:
Inventors:
Hongliu Du, Dunlap, IL (US);
Noah D. Manring, Chillicothe, IL (US);
Assignee:
Caterpillar Inc., Peoria, IL (US);
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
F04B 4/900 ;
U.S. Cl.
CPC ...
F04B 4/900 ;
Abstract
A method and apparatus for controlling a pump discharge pressure of a variable displacement hydraulic pump having a swashplate, and a servo valve for controlling an angle of inclination of the swashplate. The method and apparatus includes sensing a value of an actual pump discharge pressure, determining a desired control pressure using a first feedback linearization control law, determining a desired servo valve spool position using a second feedback linearization control law, and controlling the value of the actual pump discharge pressure as a function of the first and second feedback linearization control laws.