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:
Mar. 05, 1996
Filed:
Mar. 14, 1995
Thomas G Van Sistine, Menomonee Falls, WI (US);
A. O. Smith Corporation, Milwaukee, WI (US);
Abstract
A switched reluctance electronic motor includes a rotor mounted for rotation about an axis and including a plurality of rotor poles. A stator surrounds the rotor and includes at least three stator phases. The motor also includes a circuit for controlling the motor, the circuit includes a pulse generator for supplying a seek current to each of the phases of the motor without causing rotation of the rotor. The seek currents in the phases each have a respective seek current rise time. The rise time is a function of the proximity of the rotor poles to the respective phases. The circuit includes a series of counters for measuring the amount of time required for the seek current in each phase to reach a predetermined seek current threshold and a comparator for comparing the seek current rise times and for establishing a priority sequence determined by which of the phases has the lowest seek current rise time, the intermediate seek current rise time, and the highest seek current rise time The circuit also includes a run signal generator connected to the comparing structure for energizing a selected one of the phases based upon the priority sequence to cause rotation of the rotor.