US 5,005,805 A · Lift-turn valve and actuator assembly

Abstract

A lift-turn valve actuator is provided for tapered plug valve and slip assemblies that accomplishes vertical movement of the plug and retraction of the slips from sealing engagement with the valve body prior to rotation of the plug member 90.degree. to its open position. The valve actuator assembly includes inner fitting inner and outer sleeve members each having cam slots formed therein with the cam follower of a valve actuating stem being engaged with both cam slots. Rotation of the outer sleeve member with respect to the static inner sleeve imparts initial vertical movement to the actuator stem, valve stem and valve plug for slip retraction as an initial component of movement followed by simultaneous rotational and upward movement of the plug member until the plug member has rotated 90.degree. to its open position. The cam slots further secure the follower of the actuator pin so that the plug member will not have the possibility of downward or counterrotational movement until the outer sleeve member is rotated in the opposite position for closure and sealing.

A lift-turn valve actuator for valves incorporating a valve body and a valve seat, said valve body having therein a valve element with a valve stem extending therefrom and being moved first linearly to space the valve element away from the valve seat, then rotated between opening and closed positions and then moved again linearly to seat the valve element against the valve seat, said valve actuator comprising:

(a) a valve actuator housing having an internal actuator chamber disposed therein;
(b) an inner sleeve being disposed in fixed relation with said valve body, said inner sleeve defining opposed cam surfaces forming opposed guide slots each having upper and lower substantially vertically oriented guide slot sections and an intermediate inclined guide slot section, said inner sleeve forming an actuator stem passage centrally thereof;
(c) an outer sleeve being rotatably disposed about said inner sleeve and positioned within said actuator chamber, said outer sleeve defining cam surfaces forming opposed cam slots each having upper and lower inclined sections and a substantially vertically oriented intermediate section together with smoothly curved transition sections therebetween, said outer sleeve receiving a driving means about a portion thereof and being disposed within a portion of said actuator chamber for operable coupling to an extended driving means;
(d) an actuator stem for connection in nonrotatable relation with said valve stem and being disposed for rotary and linear movement within said actuator stem passage;
(e) cam follower means extending transversely from opposed sides of said actuator stem and being movably received within respective guide slots and cam slots;
(f) means for restraining relative linear movement of said outer sleeve;
(g) means restraining rotary and linear movement of said inner sleeve;
and
(h) said internal and external driving means imparting rotary movement to said outer sleeve thus inducing interaction of said cam slots and guide slots with said cam follower means for imparting movement to said cam follower means and said actuator stem, said lower vertically oriented sections of said guide slots of said inner sleeve and said lower inclined sections of said cam slots of said outer sleeve cooperatively inducing linear movement to said cam follower means and actuator stem during a first rotary component of movement of said outer sleeve in one direction said intermediate inclined sections of said guide slots and said vertically oriented intermediate sections of said cam slots cooperatively inducing simultaneous rotary and linear movement to said cam follower means and said actuator stem during a second component of rotary movement of said outer sleeve in said one direction, whereby said cam follower means and actuator stem are initially moved linearly and then moved linearly and rotationally during rotation of said outer sleeve to the open position, and then moved linearly and rotationally during rotation of said outer sleeve to said closed position and then again moved linearly.

6 more elements

Lift-turn valve and actuator assembly

Life of this patent

Lift-turn valve and actuator assembly

Life of this patent

Abstract

Claims13