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. 14, 1979
Filed:
Nov. 22, 1976
Isao Imai, Yokohama, JP;
Mitsuru Muto, Yokohama, JP;
Ishikawajima-Harima Jukogyo Kabushiki Kaisha, Tokyo, JP;
Abstract
Disclosed is a hydraulic servomechanism including a control loop consisting of an input device, an adder-amplifier, a servovalve, a cylinder or actuator and a load operatively connected in the order named for controlling the position of the load, a position feedback loop and an acceleration feedback loop. In one embodiment of the invention, the hydraulic servomechanism further includes a feedback loop wherein an output from an accelerometer or pressure sensor for detecting a differential pressure across a piston in the cylinder and an error signal from the adder-amplifier are arithmetically processed and fed back to the adder-amplifier. In another embodiment, the hydraulic servomechanism further includes an additional feedback loop wherein an output from a two-input adder to which are applied a signal representative of a supply pressure of working oil to be delivered from the servovalve to the cylinder and a signal representative of a pressure difference across a piston of the cylinder is arithmetically processed and fed back to a divider inserted between the adder-amplifier and the servovalve. In both embodiments, shocks are substantially eliminated in a hydraulic system.