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:
Nov. 22, 1994
Filed:
Aug. 26, 1993
Applicant:
Inventor:
Joseph DiTucci, Simsbury, CT (US);
Assignee:
Other;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
H02P / ;
U.S. Cl.
CPC ...
318254 ; 318138 ; 318439 ;
Abstract
Control circuitry for a brushless direct current motor is premised on constructing phase to phase back emf signals representing the differences between the back electromotive force efforts produced in each phase winding of the motor. The phase to phase back emf signals are used to produce logic level signals having logic level changes at the zero voltage crossover points of the phase to phase back emf signals. Detection of the zero voltage crossover points is dictated by selectively activated comparator circuits. A method is also disclosed as to how the values of certain circuit elements may be derived.