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:
Oct. 31, 1989
Filed:
Feb. 26, 1988
Applicant:
Inventor:
Shigeyuki Takagi, Gifu, JP;
Assignee:
Teijin Seiki Co., Ltd., , JP;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
G05B / ;
U.S. Cl.
CPC ...
318621 ; 318632 ;
Abstract
A servo system having an improved loop stability and response time. A phase shifting circuit is inserted in the feedback loop providing an open loop phase lag characteristic at a resonance frequency of a load system in a range of -270.degree. to -360.degree.. The transfer function of the phase shifting circuit is preferably of the form: ##EQU1## where .tau..sub.3 and .tau..sub.4 represent time constants of the circuit.