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. 17, 2016
Filed:
Aug. 23, 2013
Ld Design Electronics Ab, Odeshog, SE;
Lars Dernebo, Odeshog, SE;
LD Design Electronics AB, Odeshog, SE;
Abstract
The method is for making a brushless direct-current (DC) motor quieter. A predetermined high frequency pulse width modulated (PWM) signal is generated. The PWM signal is sent to a first filter. The first filter truncates the PWM signal to provide the PWM signal with a rise time. The rise time allows transistors connected thereto to open smoothly. A second filter is provided that has a non-polarized capacitor. In a coil switching process, the non-polarized capacitor operates as a voltage or current absorption circuit between driving transistors. The coil switching process creates transient energy of voltage transients. The non-polarized capacitor absorbs the transient energy.