GB493564A - Improvements in or relating to clutches - Google Patents

Abstract

493,564. Friction clutches. BORG-WARNER CORPORATION. April 23, 1937 Nos. 11664 and 11665. Convention dates, Sept. 14, 1936 and Nov. 27, 1936. [Class 80 (ii)] A self-energizing friction clutch comprises a driven disc 7 located between the face of a driving flywheel 1 and a relatively-rotatable presser plate 20 which is urged towards engagement by springs 27, abutting against a cover-plate 10 secured to the flywheel, and which is adapted to be retracted through the agency of radial levers 50. The plate 20 is provided with lugs 35 across each pair of which is secured a plate 36 provided with a conical recess 38, while members 41, press-fitted into the cover, have opposed conical recesses 39, a ball 42 being arranged between each pair of co-operating recesses so that, as relative rotation between the plate 20 and the flywheel takes place during drive, the spring engagement pressure is augmented by the wedging action of the balls. The recesses 38 and 39 are preferably of different conicity. The levers 50, Fig. 1, the inner ends of which coact with the throw-out bearing 13 through adjustable studs 51, are pivotally mounted in forked brackets 32 secured to the cover, and their outer ends are held in contact, through balls 56 retained and capable of rolling in transverse grooves in the lever ends, with the plates 36 through the action of anti-rattle springs 58. The plate 20 is centred on a ring 21 which is slidably carried by the brackets 32, the forked ends of the latter engaging in apertures in the ring, and which is interposed between the plate 20 and the springs 27. The ring 21 carries friction facings 24 engaging the plate 20 so as to damp the free rotation of the latter. Each ball 42 is mounted in a retainer 45 having a stem 46 which is slidable and rockable in an aperture in the adjacent bracket 32, outward movement of the stem under the action of a spring 49, assisted by centrifugal force, being limited by a cross-pin. As the balls 42 are thus held in contact with the surfaces of the recesses, noise and jolts during torque reversals are prevented. In the modified form shown in Fig. 12, the ring 21 is held against rotation relative to the cover by means of flexible corrugated plates 65, one end of each of which is secured to the cover while the other end is secured to the ring. The forked ends of the brackets 32 still engage in the apertures of the ring 21, but with substantial circumferential clearance, so as to restrain the brackets against outward movement. Further, spring washers 70 are disposed between the cover and the body of the brackets, and the securing nuts 71 are rounded so as to permit a slight rocking movement of the brackets. The adjustable studs on the inner ends of the levers 50 are dispensed with, adjustment being effected by the nuts 71.