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:
Feb. 10, 1998
Filed:
Jun. 20, 1996
Koichi Inagaki, Chiba, JP;
Noriaki Okada, Gunma, JP;
Sony Corporation, Tokyo, JP;
Sanyo Electric Co., Ltd., Osaka, JP;
Abstract
A brushless sensorless motor driving circuit for driving a motor having a rotatable rotor and a plurality of excitation coils in which a motor starting mode may be smoothly switched to a normal driving mode so as to reduce a fluctuation in a starting time. The sensorless motor driving circuit includes a detection circuit for detecting a generated induction voltage from the excitation coils; a phase-locked loop circuit for generating a clock pulse; a delay pulse generating circuit for generating a delay pulse based on the clock pulse; a switching signal generating circuit for generating conduction switching signals in accordance with the delay pulse and an output signal from the detection circuit for causing an excitation pattern of the excitation coil to be switched to another excitation pattern; and starting pulse inserting circuits for inserting a starting pulse based on the clock pulse in the detection circuit when the induction voltage is not generated.