GB787579A - Improvements in or relating to clutch plates - Google Patents

Abstract

787,579. Friction clutches. GATES, G. R. G. Dec. 17, 1954 [Aug. 31, 1954], No. 25194/54. Class 80 (2). A clutch plate for use in a clutch running immersed in oil is provided with continuous grooves on a friction face, the radial distance of various points on each groove from the centre of rotation of the disc altering according to the angular position on the disc of the point considered. In one form, concentric circular grooves 36, Fig. 2, on one face 34 of a clutch disc 15, are arranged with their common centre offset to the left by an amount a from the centre of rotation of the disc. In. another form, grooves 43, Fig. 5, on the disc face 34 are in the form of ellipses. As a further modification, the grooves can have a wavy shape. The disc 15 shown in Fig. 2 is provided with further similar concentric circular grooves 37 on its reverse face, also disposed eccentrically to the centre of the disc. The centre of the grooves 37 lies on the diameter passing through the centre of the grooves 36 and the centre of rotation and is also a distance a from the latter but is to the right thereof. Elliptical grooves 46, Fig. 5, are provided on the reverse side of the disc 15 to that having the elliptical grooves 43, the major axes of the ellipses 46 coinciding with the minor axes of the grooves 43. The discs may be made from cast iron or medium carbon steel, and can coact with plane clutch discs of bonded asbestos or sintered metal, respectively. The discs 15 are shown used in a multi-disc clutch between a driving flywheel 10, Fig. 1, and a driven shaft 11. A coil spring 26 biases a plate 25 to the right of Fig. 1 to engage with the longer arm of cranked levers 20 pivoted at 21 on a plate 28 secured by rods 19 to the flywheel 10. The cranked levers are thus turned about the pivots 21 so that their shorter arms push at 22 on a presser plate 23 to engage the clutch. A thrust ring 27 is carried by pins 29, passing through holes in the plate 28 and contacting the plate 25. When the thrust ring 11 is moved to the left by the usual linkage (not shown), the thrustof the spring 26 is thus taken away from the cranked levers and the clutch is disengaged. Specification 743,192 is referred to,