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. 01, 1995
Filed:
Feb. 16, 1994
George Codina, North Hollywood, CA (US);
Thomas M Baker, Peoria, IL (US);
Lisa A Creger, Metamora, IL (US);
J Thomas Vachon, Peoria, IL (US);
Caterpillar Inc., Peoria, IL (US);
Abstract
In one aspect of the present invention, an apparatus for determining an extended length of a hydraulic cylinder is disclosed. A piston and rod are contained within a cylindrical housing of the hydraulic cylinder. A coil is wound about the rod and is attached to the piston and an end of the cylindrical housing. The coil extends and retracts with the reciprocating movement of the piston. An oscillator is coupled to the coil and produces a position signal in response to the inductance of the coil. A circuit receives the position signal, and determines the incremental linear position and velocity of the piston and rod relative to the housing in response to the frequency of the position signal.