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. 18, 2004
Filed:
Sep. 06, 2000
Yosuke Hamada, Odawara, JP;
Iwao Oshimi, Naka-gun, JP;
Jiro Abe, Sagamihara, JP;
Kiyotada Ito, Odawara, JP;
Shinsuke Nakagawa, Tsuchiura, JP;
Hitachi, Ltd., Tokyo, JP;
Abstract
Settling response characteristics after change-over from a speed controller to a position controller is attained. Fluctuations in a time taken until change-over is made from the speed controller to the position controller are reduced to stabilize a moving time and to shorten an access time. To this end, a position controller generates a drive signal of a linear or primary function of time in such a manner that a position deviation signal responds to it with a ternary-order function of time which becomes zero in a desired finite settling time. Further, a feedforward signal generator is provided to reduce a follow-up error to a target position signal as an output of a target position signal generator. Furthermore, a switching judger is provided to start its judging operation after the position deviation signal reaches a predetermine position deviation and to perform switching operation from the speed controller to the position controller when the position deviation signal is not larger than a value corresponding to a proportional multiple of a speed signal.