GB592916A - Improvements in or relating to overload release clutches for mechanical drives - Google Patents

Abstract

592,916. Overload release clutches. GLOVER, WEBB, & LIVERSIDGE, Ltd., and EVANS, L. W. June 8, 1945, No. 14555. [Class 80(ii)] A clutch permanently disengaged on overload comprises an operating member connected to a driving member through a series of springs whose ends are mounted on each member and which shorten by flexion on overload to disengage a dog clutch member rotating with but having limited axial freedom relative to the operating member, so that the latter can return to its no-load position on the cessation of overload leaving the clutch disengaged. As shown, an operating disc 6, Fig. 1, connected to a driving disc 3 on the tubular driving shaft 1 by built-up or unitary blade springs 21, is slidably splined on a driving clutch member 8 itself free to rotate and slide on the shaft 1. The member 8 has axial dogs co-acting with similar dogs 13 on a driven clutch member 14 also journalled on the shaft 1 and carrying a driven sprocket 16. The springs 21 pass through radial slots in the discs 3, 6 and are secured thereto by spring rings 37, Fig. 4, clipped to the discs. Flexing of the springs 21 under excessive torque causes the disc 6 to move the member 8 to the left through an abutment ring 10 mounted thereon, the dogs being disengaged and remaining so until manually re-engaged through a plunger 22 sliding in the shaft 1 and carrying a rod 27 co-acting with the rear of the member 8. Alternatively, a selector fork on the member 8 may provide manual engagement and disengagement. There is a rotatable casing 31.