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. 23, 1977
Filed:
Sep. 23, 1975
Applicant:
Inventors:
Austin Hughes, Leeds, EN;
Peter John Lawrenson, Leeds, EN;
Assignee:
National Research Development Corporation, London, EN;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
H02K / ;
U.S. Cl.
CPC ...
318696 ; 310 / ;
Abstract
A stepper motor has impedance in series with each drive coil and the value of the impedance is changed during each drive pulse. Two different paths for current to a drive coil may be provided each having a different value of impedance and the current to the drive coil is switched between the two paths during each drive period.