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, 1993
Filed:
Jun. 29, 1992
Applicant:
Inventor:
Ali A Bitar, Peoria, IL (US);
Assignee:
Caterpillar Inc., Peoria, IL (US);
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
G01R / ; F01B / ;
U.S. Cl.
CPC ...
324635 ; 324633 ; 324636 ; 324649 ; 92 / ; 91-1 ; 73116 ;
Abstract
An apparatus is adapted to detect the linear extension of a hydraulic cylinder. The hydraulic cylinder defines a variable length coaxial resonant cavity. Under the control of a controller, a transmitting section and a receiving section are used to determine the linear extension of the hydraulic cylinder. The controller detects two subsequent harmonics of the resonant frequency and responsively determines the resonant frequency. The linear extension is determined as a function of the resonant frequency.