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. 24, 2005
Filed:
Mar. 09, 2004
Yoshifumi Kuwano, Kiryu, JP;
Akio Takemori, Kiryu, JP;
Hiroaki Taka, Kiryu, JP;
Yasuo Matsuda, Kiryu, JP;
Yoshihiro Okumatsu, Miyazaki, JP;
Atsuo Kawamura, Yokohama, JP;
Yukinari Takahashi, Kiryu, JP;
Yoshifumi Kuwano, Kiryu, JP;
Akio Takemori, Kiryu, JP;
Hiroaki Taka, Kiryu, JP;
Yasuo Matsuda, Kiryu, JP;
Yoshihiro Okumatsu, Miyazaki, JP;
Atsuo Kawamura, Yokohama, JP;
Yukinari Takahashi, Kiryu, JP;
Japan Servo Co., Ltd., Tokyo, JP;
Abstract
A stepping motor driver which drives a stepping motor for position and speed control. The stepping motor driver comprises: a current control means which outputs values corresponding to applied voltages; current sensors which detect phase currents; and a magnetic pole position estimation unit which uses the values corresponding to applied voltages and detected phase current values as outputs of the current sensors to obtain a magnetic pole position estimate. The magnetic pole position estimation unit calculates a magnetic pole position estimate from speed electromotive force estimates or from differences between phase currents at zero speed and detected phase current values.