GB717433A - Improvements in or relating to friction clutches or brakes - Google Patents

Abstract

717,433. Friction clutches. COMPRESSION IGNITION, Ltd., and CHAPMAN, C. W. Dec. 17, 1952 [Jan. 25, 1952], No. 2170/52. Class 80 (2) [Also in Group XXXIV] A friction clutch or brake of the type having relatively rotatable elements on one of which are mounted friction elements movable either by centrifugal force or by operator actuated means against resilient restraint into engagement with the other element, is characterized by the friction elements of the clutch or brake being moved against torsionally resilient restraint into engagement with a driving or driven member by the said operator actuated means, which consist of one or more members moved axially of the clutch, &c. into engagement with the friction elements, the latter thereby being moved radially. As shown applied to a'clutch, a driving (or driven) shaft 26 and drum 25 can be engaged by shoes 19 on a driven (or driving) hub 10 fast on a shaft 12; the shoes are carried on levers 17 which are connected by resilient elements of rubber or the like 16 both to the hub and to the shoes, the resilient elements connecting the levers to the hub being torsionally stressed on assembly to hold the shoes in the disengaged position. Each resilient element comprises radially prestressed rubber, &c. bonded to inner and outer sleeves 14, 15. Engagement is produced by axial sliding movement of a sleeve 34, feathered on the shaft 12, carrying three-armed levers 32 in rubber bushes 35, rollers 41 on arms 38 of these levers being engageable with bearing pads 28 on the inner sides of the shoes 19; the clutch is shown in the engaged position in the top half of Fig. 1, and in the disengaged position in the bottom half thereof. Arms 42 of the levers 32 lie in grooves in a sleeve extension 43 of the sleeve 34, one side of this groove being formed by a ring nut 44 which can be screwed along the sleeve extension 43 and which is engaged by the arms 42,; such screwing of the ring nut 44 adjusts the radial positions of the arms 38 and enables the clutch engaging pressure to be controlled and adjustment for wear to be effected. Each of the arms 42 and/or bearing pads 28 may also be provided with means for the individual adjustment of the engaging pressure applied to each shoe. Counter-weights 27 on extensions of the levers 17 can be arranged to partially, completely or over counteract the engaging effect of centrifugal force on the shoes.