Abstract: A valve stem lifter assembly which operates to alternatively open and close a valve, includes a rotatably mounted rotary shaft having a top end axially aligned with a riser with a rigidly connected pull shaft and an opposite end axially aligned with an operator for selectively producing rotational movement of the rotary shaft and corresponding axial movement of the riser and pull shaft. The rotary shaft is rotatably connected to the riser by radius set screws positioned horizontally in the grooves of the rotary shaft. A plurality of guide shaft rods passing through the riser interconnects the riser to the valve stem lifter assembly to prevent axial separation of the riser and rotary shaft, and rotation of the riser, while permitting free relative rotation of the rotary shaft and axial movement of the riser and pull shaft.

Abstract: A valve stem lifter assembly which operates to alternatively open and close a valve, includes a rotatably mounted rotary shaft having a top end axially aligned with a riser with a rigidly connected pull shaft and an opposite end axially aligned with an operator for selectively producing rotational movement of the rotary shaft and corresponding axial movement of the riser and pull shaft. The rotary shaft is rotatably connected to the riser by radius set screws positioned horizontally in the grooves of the rotary shaft. A plurality of guide shaft rods passing through the riser interconnects the riser to the valve stem lifter assembly to prevent axial separation of the riser and rotary shaft, and rotation of the riser, while permitting free relative rotation of the rotary shaft and axial movement of the riser and pull shaft.

Abstract: A valve stem lifter assembly which operates to alternatively open and close a valve, includes a rotatably mounted rotary shaft having a free end axially aligned with a pull shaft and an opposite free end axially aligned with an operator for selectively producing rotational movement of the rotary shaft and corresponding axial movement of the pull shaft. The rotary shaft is rotatably connected to a valve riser element by radius set screws positioned axially in the grooves of the rotary shaft. A plurality of guide shaft rods interconnects the riser to the valve stem lifter assembly to prevent axial separation of the riser and rotary shaft while permitting free relative rotation of the rotary shaft and linear movement of the pull shaft.