GB391548A - Improvements in and relating to clutch couplings for power transmission purposes, particularly the starting of engines and variable speed ratio transmission - Google Patents

Abstract

391,548. Turning-gear. STUART, TURNER, Ltd. and PLINT, A. F., 43, Market Place, Henley-on-Thames. Jan. 20, 1932, No. 1753. [Class 7 (v).] The invention relates to clutches in which the grip of a shoe, selftightened by toggle action, is relieved by overrunning of the driven member, and the shoe is centrifugally thrown out of action as the speed of the driven member r rises, The clutch is particularly applicable to starters for engines driving lighting and pumping installations, in which the electric starting-motor may require to be recoupled to the engine after a false start. An electric motor (not shown) drives by belt, toothed, or chain gearing a wheel 2 rotatable on the bearing 1 of an engine crank shaft 5, to which is keyed a disc 4. One or more bell-crank levers 8, preferably having weighted ends, are pivoted at 9 to the disc, their shorter arms 7 being connected at 10 to friction shoes 6 bearing, under the pull of springs 12, on a drum 3 integral with the sprocket &c. 2. The arms 7 are so inclined that, on counterclockwise rotation of the drum 3, the shoes are forced into firm engagement until the disc 4 tends to drive, the levers 8 centrifugally lifting the shoes when the engine speed exceeds that of the drum, but returning them into action if the engine slows down. Stops 11 may be provided to limit retraction and prevent tilting of the shoes.