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. 05, 1997
Filed:
Nov. 30, 1995
Applicant:
Inventor:
Isao Ushikoshi, Nagano, JP;
Assignee:
Kabushiki Kaisha Sankyo Seiki Seisakusho, Nagano, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
G05F / ;
U.S. Cl.
CPC ...
388815 ; 388814 ; 388908 ; 388813 ;
Abstract
A device for detecting the speed of a plural-phase motor in which a speed deviation occurring every m periods is eliminated, to provide a speed detection signal high in accuracy at low cost. The motor speed detecting device in which, among drive signals driving a plural-phase motor, m-phase drive signals (where m is a natural number which is not less than two (2) and equal to or smaller than the number of phases of said motor) are detected, and combined to form a signal, comprises a frequency divider adapted to subject the signal thus formed to 1/(m.times.n) frequency division (where n is a natural number).