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. 07, 2002
Filed:
Feb. 15, 2000
Sanyo Electric Co., Ltd., Osaka, JP;
Abstract
In order to brake a brushless motor in a forward rotation to give a reverse rotation force, source-side and sink-side transistors for supplying driving circuits *a, *b, *c, *d, *e, *f are periodically switched on and switched off based on the oscillation frequency of an oscillator ( ) when a both end voltage of a current detection resistance ( ) is higher than a reference voltage Vref. Moreover, the transistors are kept in an ON state all the time when the both end voltage of the current detection resistance ( ) has lowered below the reference voltage Vref. With this arrangement, damage to a source-side transistor due to a large current flowing thereinto when the motor rotating in a reverse direction can be prevented.