GB434528A - Improvements in an automatic clutch - Google Patents

Abstract

434,528. Friction clutches. DEHN, F. B., 103, Kingsway, London.-(Borg & Beck Co. ; 6558, South Menard Avenue, Chicago, U.S.A.) Feb. 2, 1934, No. 3528. [Class 80 (ii)] In a centrifugal friction clutch comprising a driven plate 13 interposed between a driving flywheel 11 and a presser plate 12 rotating with the flywheel, plates 34 and 36 disposed between the plate 12 and a cover 17 secured to the flywheel are urged towards each other and the plate 12 towards the plate 36 by springs 40 encircling shouldered studs 37 and 41 secured to the plates 36 and 12 respectively, the studs being guided in apertures in the cover 17. Springs 35, encircling the springs 40, act between the cover 17 and the plate 34. Two sets of weights 42, 42<1>, which may be formed of laminae secured by rivets 43, have feet 44 which extend through apertures in the plate 34, the toes 45 engaging the plate 34 while the heels 46 of the weights 42 engage the edges of slots in the plate 36 and the heels of the weights 42<1> engage the edges of inserts 47 in the plate 12. Radial levers 26 pivoted on studs 28 adjustably mounted in the cover 17 coact at their inner ends with a control collar 22, while their outer ends engage apertures in a flange 33 formed on the plate 34. There are three weights 42<1>, six weights 42, three studs 41, and twelve studs 37. With the collar 22 held in intermediate position, the clutch functions automatically in two stages. At a predetermined speed, the weights 42<1> move centrifugally outwards and, due to the tilting of the feet 44, move the plate 12 to the left against the action of the three associated springs 40, as shown in Fig. 2, thus producing partial clutch engagement. As the speed increases, the weights 42 come into action to move the plate 36, and with it the plate 12, to the left against the action of the twelve associated springs 40, as shown in Fig. 3, thus producing final clutch engagement, the reaction causing the plate 34 to move slightly to the right against the action of the springs 35 so as to relieve the levers 26 from load. At greater speeds, the weights contact with the flange 33. By moving the collar 22 to the left, however, clutch disengagement at all speeds is effected, while, by moving the collar to the right, the springs 35 effect clutch engagement at all speeds.