Patent GB-349555-A (GB)
Title: Improvements in friction clutches
IPC: F16D13/71
Filed: 1930-02-28
Abstract: 349,555. Friction clutches. RUSSELL MANUFACTURING CO., Middletown, Connecticut, U.S.A.-(Assignees of Tower, E. V. J. ; Ferguson Avenue, North Syracuse, New York, U.S.A.) Feb. 28, 1930, No. 6693. Convention date, March 26, 1929. [Class 80 (ii).] Securing clutch members on shalts.-In friction clutches engaged by a spring-urged presser-plate, disengaging-levers fulcrumed between their ends are so arranged with a sliding connection to the presserplate that their effective ratio varies during disengagement of the clutch. The presser-plate is preferably so stiffened and the clutch-springs so disposed as to avoid distortion and uneven pressures. Bent radial levers 32, Figs. 1 and 2, pivoted at 33 on the cover-plate 26 of the flywheel 20, are actuated by a sleeve 29 and bear at their outer ends, through ball-joints 34 and lubricated slide-blocks 35, on plates 36 secured to lugs 37 on the presser-plate 38, so that, during declutching against springs 42, the mechanical advantage of the levers progressively increases. The lugs 37 are of rectangular section, drive being communicated from slots in the plate 26 to the longer sides, which are oblique to the radius, in order to produce a self-centring action. The cast-steel presser-plate 38, Fig. 6, may be stiffened against distortion by circumferential ribs 44, and, in large clutches, also by radial and inclined ribs 46, 45, the ribs 44 merging into ribs surrounding the spring-.seatings 41. These seatings are preferably arranged in groups of two or more about the lugs 37, each seating of a group being at a different distance from the shaft, in order to dis. tribute the load on the presser-plate. The spider arms 57 of the driven plate 40 abut together at their inner ends and are secured between flexible washers 54, Figs. 1 and 5, which are spaced by a heat-insulating ring 55. The parts 54, 55 have flared slots receiving bundles of leaf-springs 50, acting to damp out torsional vibration. The springs 50 are held at one side by a ring 52 in radial slots 49 in a flange 48 of a hub 47 splined to the driven shaft 23, the other sides being held by a ring 51, keyed to the hub, in slots s formed by spaced sectors 51<1> welded to the ring 51. The hub structure is held d together by shouldered rivets 53, which engage enlarged or elongated holes in the parts 54, 55. The Specification as open to inspection under Sect. 91 (3) (a) comprises also the following subjectmatter :-The driven plate 40 includes a flexible friction annulus 60, Fig. 5 (Can-. celled), made up of independent sections overlapping and preferably lubricated at their ends 59, and moulded on the bifurcated and serrated ends 58 of the flexible spider arms 57. Alternatively, the ring 60 is woven in a single strip with pockets in which the tines 58 are inserted, the strip having its ends abutting between one pair of tines and being mounted with initial tension to prevent wrinkling or bulging under centrifugal and other forces. The spring-seatings 41 may be of varying depths or the springs 42 of varying strengths, whereby it is stated that successive and hence gradual action of springs of the same length is obtained. This subject-matter does not appear in the Specification as accepted.