Pneumatic operating means for a valve

Abstract

Abstract A PNEUMATICALLY OPERATED VALVE ACTUATOR EMPLOYS A CENTRALLY LOCATED PISTON ROD WHICH IS SLIDABLY SUPPORTED OVER A SUBSTANTIAL LENGTH OF ITS TRAVEK BY UPPER AND LOWER GUIDING RAILS OR TRACKS AND WHICH IS MOVABLE IN RESPONSE TO THE RECEIPT OF FLUID OPERATING PRESSURES WHICH ARE DIRECTED SIMULTANEOUSLY THROUGH TWO BRANCHES OF A FLUID CIRCUIT INTERNALLY OF THE ACTUATOR AND AGAINST THE FACES OF A PAIR OF OPPOSITELY DISPOSED PISTONS CARRIED BY THE PISTON ROD SO THAT THE BRANCH FLUID CIRCUITS COOPERABLY POWER THE ACTUATOR. TOTAL PISTON AREAS MAY BE VARIED BY CHANGING OR ELIMINATING CYLINDERS. ADDITIONALLY, THE ACTUATOR MAY BE EMPLOYED FOR PLACING ITS CORRESPONDING CONTROLLED VALVE IN A DESIRED FULLY OPEN OR FULLY CLOSED POSITION IN RESPONSE TO AN ALARM CONDITION BY A BIASING ARRANGEMENT HAVING SPRING MEANS WHICH IS LOADED BY OPERATION OF THE ACTUATOR. THE ACTUATOR IS PREFERABLY CONSTRUCTED PRIMARILY OF PLASTIC COMPONENTS TO MINIMIZE FRICTION AND PROVIDE FOR EASE IN FORMATION OF THE FLUID CIRCUITS THEREIN.

Inventors

• 👤 Malcolm D Clark

Bibliographic Details