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:
May. 10, 2011
Filed:
Nov. 16, 2007
Robert G. Brown, New Hartford, CT (US);
Robert G. Brown, New Hartford, CT (US);
The Bergquist Torrington Company, Chanhassen, MN (US);
Abstract
A commutation circuit for driving a brushless DC motor is controlled according to a commutation cycle composed of alternating primary steps and transitional steps. The commutation circuit includes pairs of field effect transistors coupled in series between the high voltage and low voltage terminals of a DC power supply. Output terminals between each pair of transistors are individually coupled to the phases of a DC motor. A controller operates the commutation circuit to selectively set the phases at active and inactive states. The controller further employs a plurality of voltage control functions individually associated with the motor phases to selectively modulate the voltage applied to one of the phases during the active states, to provide transitional steps in the commutation cycle during which the applied voltage is modulated to reduce its magnitude with respect to the high voltage or the low voltage.