(under subclass 213) Subject matter wherein the mechanical movement comprises means having a continuous helical rib which is operable to reciprocate the movable valve member through connecting means but which does not impart the rotary motion of the screw to the valve member.
SEE OR SEARCH THIS CLASS, SUBCLASS:
82+, for screw actuated valves wherein the actuator is nonpositively connected to the valve head so that there is manual control in both closed and open position.
84+, for valve heads movably connected to the stem for accommodation to the valve seat.
215+, for screw type actuators in which the rotary movement of the screw is transmitted to the movable valve member.
