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:
Mar. 30, 1993
Filed:
May. 01, 1992
James M Smietana, West Seneca, NY (US);
Moog Controls, Inc., East Aurora, NY (US);
Abstract
A hydraulic servo valve arangement of the type having a hydraulic amplifier followed by a spool type servo valve second stage, includes a deceleration control mechanism. A spindle-type positioner has first and second positions which respectively permit and block flow of fluid from the first amplifier stage to the first end of the second stage spool. The hydraulic actuator urges the positioner into its first position, and a spring urges the positioner into a second or closed position in the event a failure mode is encountered. A solenoid valve has a communicating port coupled through a dropping orifice to a source of fluid supply and a second port coupled to drain, such that in an actuated condition, input port is at high pressure but in an unactuated condition the input port drops to low pressure. Relief channels and in fluid communication with the one end of the spool member have metered orifices to limit the flow of hydraulic fluid when the spool transits to its null position. Relief passages in communication with the positioner piston have respective transit and null override orifices which achieve smooth movement of the positioner to push the spool member to its set position.