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:
Jul. 07, 1998
Filed:
Aug. 23, 1996
Nobuo Matsui, Kanagawa-ken, JP;
Kabushiki Kaisha Toshiba, Kawasaki, JP;
Abstract
A circuit controls a brushless DC motor having a magnetic rotor and a stator coil. The circuit has a switching element for switching a current to the stator coil to rotate the rotor. The circuit compares a voltage induced in the motor with a neutral voltage of a DC power source with no delay to provide a positional detection signal. The circuit has a one-chip microcomputer for examining a PWM waveform signal used to generate a synchronous signal and the switching timing of the switching element. The microcomputer samples the positional detection signal only during intervals in which a current is supplied to the stator coil, and carries out other processes during intervals in which no current is supplied to the stator coil.