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:
Jun. 08, 2010
Filed:
Nov. 19, 2007
Wang Hay Kenneth Tsui, Kwai Chung, HK;
Wai Chuen Gan, Kwai Chung, HK;
Shing Wai Tam, Kwai Chung, HK;
Gang Ou, Singapore, SG;
Hon Yu Peter NG, Kwai Chung, HK;
Wang Hay Kenneth Tsui, Kwai Chung, HK;
Wai Chuen Gan, Kwai Chung, HK;
Shing Wai Tam, Kwai Chung, HK;
Gang Ou, Singapore, SG;
Hon Yu Peter Ng, Kwai Chung, HK;
ASM Assembly Automation Ltd., Hong Kong, HK;
Abstract
A method for damping vibrations in a stepper motor with micro-stepping control which comprises the steps of identifying the force amplitudes and phase shifts of multiple harmonic detent torques of the stepper motor, such as the first, second and fourth harmonic detent torques, and tuning the stepper motor with different current commands until minimum friction and resistive torque are obtained. Thereafter, a compensating harmonic current derived from said force amplitudes and phase shifts of the said multiple harmonic detent torques is injected into a current command during operation of the stepper motor to compensate for torque ripples.