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:
Apr. 14, 1981
Filed:
Jun. 25, 1980
John M Cory, Old Lyme, CT (US);
Ronald A Olansen, Old Lyme, CT (US);
Joseph A Wucik, Jr, Westerly, RI (US);
Posi-Seal International, Inc., Stonington, CT (US);
Abstract
A power-driven quarter-turn valve actuator includes a reciprocating drive member in the form of a rod mounted perpendicularly to and spaced a preselected distance from a valve stem. A crank arm is coupled to the valve stem so that the axis of the crank arm makes an angle of between approximately 60.degree. and 100.degree. with a line intersecting the stem axis and perpendicular to the rod axis when the valve is shut and makes an angle of between minus 30.degree. and plus 10.degree. with said line when the valve is fully open. A link member connects the outer end of the crank arm to a point on the reciprocating rod. The preselected distance between actuator rod and valve stem, and the lengths of the crank arm and link, are chosen to produce a variable actuator torque output curve that closely matches the operating torque requirements of the valve. Preferably, the length of the link is at least equal to the preselected distance between the actuator rod and the valve stem, and the length of the crank arm is greater than the length of the link but less than twice said preselected distance. A pneumatic diaphragm motor drives the actuator rod from valve shut to valve open against a spring biasing means which urges the valve shut. Different spring rates can be provided to adapt the actuator to different available air pressures.