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:
Jul. 11, 2006
Filed:
Oct. 22, 2003
Masahiro Saitou, Tokyo, JP;
Masahiro Saitou, Tokyo, JP;
Sumitomo Heavy Industries, Ltd., Tokyo, JP;
Abstract
A precision positioning device comprises a hydraulic cylinder extending along the vertical direction and a piston member accommodated in the cylinder. The inside of the cylinder is divided into two chambers by a piston head of the piston member. A hydraulic circuit supplies a fluid at a constant pressure to one of the two chambers and supplies the fluid at a controlled flow rate to the other of the chambers via a servo valve. A control system performs position control with respect to the piston member by controlling the servo valve based on a detection signal from the position sensor, a position command value, a velocity command value, and an acceleration command value. The control system also performs force control with respect to the piston member by controlling the servo valve using detection signals from the first and second pressure sensors and a load command value.