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:
Feb. 07, 1984
Filed:
Jul. 27, 1981
Joseph A Burkhardt, New Orleans, LA (US);
Thomas W Childers, New Orleans, LA (US);
Harry R Hanson, Houston, TX (US);
Bobby M Harkrider, Gretna, LA (US);
Exxon Production Research Co., Houston, TX (US);
Abstract
A hydraulically operated actuator employs multiple metal-to-metal static seals to isolate the hydraulic fluid and to isolate the actuator from surrounding contaminating (ambient) fluids. A housing contains at least two linearly spaced apart chambers. A piston reciprocates from a retracted position to an extended position (power stroke) and from the extended position to the retracted position (return stroke) in one of the chambers (hydraulic chamber). The hydraulic chamber is separated by the piston into two sections, one of which contains high pressure hydraulic fluid and the other of which contains low pressure hydraulic fluid. A first static metal seal ring unit is designed to seal first at the completion of the power stroke of the piston to isolate the low pressure hydraulic fluid section from external contaminating fluids which may be at a higher pressure. A second static metal seal ring unit is designed to seal at the completion of the return stroke of the piston also to isolate the low pressure section from external contaminating fluids. Power for the return stroke is primarily supplied by springs, with biasing pressure from the external environment providing a lesser contribution. A third static metal seal ring unit may be employed to obtain a simultaneous seal with the first metal seal ring unit to isolate the high pressure section from the low pressure section at the completion of the power stroke of the piston.