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:
Aug. 10, 1999
Filed:
Feb. 05, 1998
Hiroshi Ohsawa, Konan, JP;
Shinichi Ohi, Konan, JP;
Kzuyoshi Horiuchi, Konan, JP;
Kouji Ando, Konan, JP;
Zexel Corporation, Tokyo, JP;
Abstract
A pulse width of a drive pulse of a brushless motor is modulated in correspondence to a setting signal for setting the rotation rate. Switching control for the current supplied to exciting coils is implemented by using an output signal from Hall elements for detecting the position of the rotor and the drive pulse. Correction of the pulse width of the drive pulse is implemented to ensure that the average voltage is maintained at a constant level even when the source voltage fluctuates so that stable rotation can be maintained over the entire rotation rate range even when the source voltage supplied to the brushless motor fluctuates and so that the fuse can be prevented from melting and the motor can be prevented from becoming damaged, which may otherwise be caused by a fluctuating source voltage.