VALVE OPERATIOR ASSEMBLY WITH ANTI-BACKDRIVING DEVICE

摘要

A high efficiency operator assembly is for a valve for controlling flow through a passage, the valve including a closure element movable between a closed position at which the member substantially obstructs the passage and an open position. The operator assembly includes a movable stem having opposing ends, a first end being connectable with the closure element such that displacement of the stem moves the closure element between the open and closed positions. A stem driver is rotatable about a central axis, engaged with the stem, and configured to displace the stem when the driver angularly displaces about the axis and an input device is rotatable about the axis. A lock mechanism or a clutch is engageable with the stem, the stem driver, or the input device to retain the closure element at a particular position when the input device remains at a particular angular position about the input axis.