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. 28, 1985
Filed:
Apr. 20, 1984
Neil H Akkerman, Houston, TX (US);
Daniel O Dewey, Houston, TX (US);
Ava International Corporation, Houston, TX (US);
Abstract
There is disclosed a gate valve which is moved to open position by an extendible and retractable, fluid-operated actuator, and which is moved to closed position, upon exhaust of operating fluid, by coil springs which urge follower parts reciprocable with a stem on the gate, and which extend from the valve body into a housing connected on the valve body, into engagement with cam surfaces on the housing. The cam surfaces are so arranged that the coil springs initially move the gate from open toward closed position with a relatively small force, and then move it into fully closed position with a force which is sufficiently larger to shear a wire line or other obstruction in the flowway of the valve body which would otherwise prevent closing of the gate.