GB619540A - Improvements relating to clutches - Google Patents

Abstract

619,540. Overload-release clutches. ARCHDALE & CO., Ltd., J., and WILSON, P. J. Sept. 4, 1946, No. 26565. [Class 80 (ii)] In an overload-release claw clutch of the kind having a pair of co-operating and coaxial parts provided on their adjacent faces with interengaging teeth having inclined or rounded contacting faces, and in which one of the parts is axially slidable and spring loaded to engage, re-engagement of the parts after slipping has occurred is prevented by a toothed ring freely rotatable on one part and coacting with the other. As shown, three circumferentially-spaced facial teeth 3 on a freely mounted member 2 engage between similarly-spaced but mutually radially displaced teeth 12, 6 on driving and driven clutch members 11, 5 respectively. The member 11 is keyed to, and the member 5 freely rotatable on, a driving spindle 1. The flanks of the teeth are inclined as shown, so that excessive torque forces the member 2 axially to the right against spring pressure until its teeth 3 disengage the teeth 6, which are shallower than the teeth 12, and engage projections 10 on the teeth 8 of a drag ring 7 freely rotatable on the member 5. The drag ring 7 then rotates with, and balks the re-engagement of, the member 2 until rotated by hand or otherwise so that the teeth 8 are again clear of the teeth 3. The torque necessary to cause disengagement is increased below a pre-determined speed by centrifugal struts 14 pivoted on an additionally spring-urged member 13 and which abut a shoulder 17 on the member 2 up to that speed.