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:
Oct. 10, 2006
Filed:
Oct. 30, 2004
Gregory J. Manlove, Kokomo, IN (US);
Robert K Constable, Kokomo, IN (US);
Ashraf K. Kamel, Indianapolis, IN (US);
Gregory A. Cobb, Kokomo, IN (US);
Duane D. Fortune, Lebanon, IN (US);
William W. Fultz, Carmel, IN (US);
Dennis P. Griffin, Noblesville, IN (US);
Thomas L. Voreis, Noblesville, IN (US);
Gregory J. Manlove, Kokomo, IN (US);
Robert K Constable, Kokomo, IN (US);
Ashraf K. Kamel, Indianapolis, IN (US);
Gregory A. Cobb, Kokomo, IN (US);
Duane D. Fortune, Lebanon, IN (US);
William W. Fultz, Carmel, IN (US);
Dennis P. Griffin, Noblesville, IN (US);
Thomas L. Voreis, Noblesville, IN (US);
Delphi Technologies, Inc., Troy, MI (US);
Abstract
The capacitance of a shielded capacitive load cell is determined so as to minimize the effect of stray or parasitic capacitance between the load cell and other objects including the shield. The load cell conductors are coupled across input and output terminals of an operational amplifier that is tied to a reference voltage. A constant current is applied to the load cell, and the resulting rate of change in voltage at the amplifier output is measured as a representation of the load cell capacitance. In a vehicle seat sensor application including an electromagnetic interference shield between the load cell and the seating surface, the amplifier output is coupled to the load cell electrode furthest from the shield, the amplifier maintains the other load cell electrode at a virtual reference voltage, and the shield is tied to the reference voltage.