| 摘要 |
An improved cam sleeve operator for use primarily with valves of the plug type in which a tapered plug is raised to unseat associated slips and then rotated to a valve open position during opening of the valve and is rotated to a valve close position and lowered to seat the associated slips for closing the valve. The operator comprises a cylindrical housing having an inverted L-shape configuration, a cam sleeve which controls the position of the valve trunnion in response to the prime mover, and a pin connecting the valve trunnion to the operator for effecting sequential vertical and rotational motion of the valve trunnion in response to unitary continuous motion of the prime mover. One particularly advantageous feature of the present invention is a uniquely shaped cam sleeve slot or helical groove of varying angle which optimizes the application of input torque for reducing prime mover peak torque requirements and for simplifying the operator structure thus reducing costs of manufacture and maintenance and significantly prolonging the operational life of the valve operator as well as reducing the overall energy consumption for each valve actuating operation. |
