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.

Date of Patent:
Jun. 10, 1997

Filed:

Jan. 16, 1996
Applicant:
Inventors:

Steven P Randall, Leeds, GB;

David M Sudgen, Leeds, GB;

William Vail, Leeds, GB;

Geoffrey T Brown, Hemingbrough, GB;

Assignee:
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
H02P / ;
U.S. Cl.
CPC ...
318616 ; 318439 ;
Abstract

A rotor position encoder for an electric motor includes a discate member mounted to rotate with the rotor shaft. The encoder has a set of radially extending features formed with angularly evenly spaced leading edges and unevenly spaced trailing edges. The leading edges induce a signal in a sensor that corresponds to the relative timing of power switches for each motor phase, The trailing edges define a cyclical code by which motor controlling circuitry is able to determine the phase of rotation of the rotor and thus establish the correct power switch actuation sequence. An electric motor control system and methods of starting electric motors also provide significant advantages.


Find Patent Forward Citations

Loading…