GB427649A - Improvements in friction clutches - Google Patents

Abstract

427,649. Friction clutches. GILLETT, E. H. J. C., 32, Marlborough Mansions, Cannon Hill, Kilburn, London. Oct. 31, 1933, No. 30216. [Class 80 (ii)] In a friction clutch comprising a driven plate 17, Fig. 1, interposed between a driving flywheel 11 and a presser plate 12, the latter is urged towards the plate 17 by engaging springs 19 and is adapted to be retracted under all conditions through radial levers (not shown) upon movement to the left of a sleeve 28 by depression of a clutch pedal 42, and a spider 32 is urged to the right, to coact with abutment nuts 39 on studs 38 secured to the plate 12, by disengaging springs 23 which are stronger than the springs 19, and is urged to the left by the centrifugal action of weights 35 pivotally mounted in circumferential slots 48 in the flywheel. Outward movement of the weights is limited by a ring 49. At low speeds, the clutch is disengaged, but as the speed increases the centrifugal effect of the weights moves the spider to the left, comprising the springs 23, until eventually the clutch is engaged with the full force of the springs 19. By operating a lever 43 through Bowden mechanism 45, the spider may be manually moved to the left so as to render the centrifugal control ineffective. As shown in Fig. 4, a lever 43, 56 controlling the spider 32 is loosely mounted on the pedal shaft 55, while a lever 40, 52 controlling the sleeve 28 is loosely mounted on a shaft 51. The arm 52 carries a roller 53 coacting with a cam 54 secured on the shaft 55. On depressing the pedal 42, the radial face 54<a> of the cam coacts with the arm 52 to move the sleeve 28 to the left, disengaging the clutch. Upon overdepression of the pedal, the roller 53 rides on to the circular portion 54b of the cam, maintaining the clutch disengaged, and the face 54<a> coacts with the arm 56 to move the spider 32 to the left to render the centrifugal control ineffective. Return movement of the spider, upon release of the pedal, is adapted to be prevented by a pawl 57 which is loosely mounted on the shaft 51 and which is connected by a spring 59 to an arm 58 connected to Bowden mechanism 45. The latter may thus be operated preselectively, the selected movement of the pawl taking place upon over-depression of the pedal 42. The disengaging springs may, alternatively, be external to the clutch, and the centrifugal weights may be mounted on an auxiliary engine-driven shaft.