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:
Sep. 03, 1991
Filed:
Aug. 21, 1989
Applicant:
Inventors:
Frank A Pizzarello, Yorba Linda, CA (US);
Clifford D Dax, Mission Viejo, CA (US);
Assignee:
Rockwell International Corporation, El Segundo, CA (US);
Primary Examiner:
Int. Cl.
CPC ...
G01P / ; G01P / ;
U.S. Cl.
CPC ...
324163 ; 310 / ; 310155 ; 310168 ; 318638 ;
Abstract
A current carrying drive coil in a magnetic field is moved by the field. An attached tachometer coil, passing through the same field, produces a voltage from which the speed of the coils may be calculated. Changes in the drive coil current produce noise in the tachometer coil. This noise is offset by combining the tachometer voltage with the voltage produced by a stationary pickup coil, which picks up only the noise.