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:
Dec. 27, 1983
Filed:
Aug. 13, 1981
Applicant:
Inventor:
Johannes F Gottwald, Park Ridge, IL (US);
Assignee:
Xerox Corporation, Stamford, CT (US);
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
H02K / ;
U.S. Cl.
CPC ...
318696 ; 318685 ;
Abstract
A stepper motor controller circuit is described. The circuit comprises four power transistors configured to drive current in either direction through a stepper motor winding. A series resistor senses instantaneous current and a chopper is used to limit this current to some predetermined maximum value. Eight diodes protect the circuit against reverse, current surges, and a flip-flop guarantees a minimum duty cycle.