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. 05, 1996
Filed:
Jul. 15, 1994
Scott W Cameron, Phoenix, AZ (US);
SGS-Thomson Microelectronics, Inc., Carrollton, TX (US);
Abstract
In a method for aligning a rotor of a polyphase dc motor in preparation for starting the motor. a first energization signal is applied to field coils of the motor in a first predetermined phase for a first predetermined time. Then, a second energization signal having a second predetermined phase displaced from the first phase by a predetermined amount is applied to the field coils for a second predetermined time period. In one embodiment, the second energization signal is applied to produce a maximum torque upon the rotor when the rotor is positioned at a location determined by the first energization signal. In the case of a three phase motor, the second energization signal is displaced by two commutations from the first energization signal. Circuitry for aligning a rotor of a polyphase dc motor in preparation for startup is also presented having circuitry for applying a first signal to selected field coils of the polyphase dc motor having a first commutative phase for a first predetermined time, and circuitry for applying a second signal to other selected field coils of the polyphase dc motor having a second commutative phase for a second predetermined time.