Valve operator de-clutch mechanism

Claim 1

A valve operator comprising: a. an output shaft having a splined portion; b. a clutch mounted for sliding movement on said splined portion of said output shaft, said clutch having lugs projecting from its opposite ends; c. a handwheel drive member coaxial with said clutch and located to one side thereof, said handwheel drive member having lugs adapted for engagement with the lugs at one end of said clutch; d. a motor drive sleeve mounted for free rotation on said output shaft, said sleeve having lugs adapted for engagement with the lugs at the other end of said clutch; e. an annular step on said sleeve; f. a flat on said annular step; g. spring means biasing said clutch toward the motor drive sleeve; h. a pivotal fork connected to and movable with said clutch for shifting said clutch on said splined portion of said output shaft; i. a pair of latch arms extending from said fork in the direction of said motor drive sleeve, one of said latch arms being slightly longer than the other, the end of said longer latch arm being adapted to abut against said annular step on said sleeve, said longer latch arm being adapted to move into said flat when said flat and longer latch arm are in alignment, thereby to allow said spring-biasing means to move said clutch and fork toward but short of said motor drive sleeve, said movement being limited by the abutment of said shorter latch arm against said sleeve step, whereby upon further rotation of said motor drive sleeve, said flat comes into alignment with said shorter latch arm, allowing said shorter latch arm to move into said flat, thereby allowing said spring-biasing means to shift said clutch fully so that said clutch lugs come into engagement with the lugs on said motor drive sleeve, and j. a self-locking input worm set for driving said motor drive sleeve.