Patent ID: 9482359
Filing Date: 2016-11-01
CPC Classification: E21B,F16K,H01H

Claim Text:
1. An electrically operated valve actuator effective for shifting a valve between open and closed positions, the valve actuator comprising: a movable member comprising a valve stem connected to a valve body, a first end surface, a second end surface, and a side surface extending between the first end surface and the second end surface, the movable member being driven by an electric motor in a linear motion between valve closing and valve opening positions, wherein electrical power to the motor is supplied via a current control comprising a supplied current detection device; the movable member, at each end of travel, is designed for an idling length of travel in the opening and closing directions during which the valve is either fully open or fully closed; the movable member is associated with a buffer positioned so that, during the idling length of travel, the torque and current required to move the movable member further in the open and closed positions of the valve, respectively, gradually increases, wherein the movable member is contained between a first wall and an opposite second wall in a valve or actuator housing, and the buffer is supported in each end of the valve or actuator housing between the first and second end surfaces and first and second walls in the valve or actuator housing, respectively; and the current detection device monitors an increase in supplied current during the idling length and stops the motor within a time window of the idling length.