GB832587A - Improvements relating to declutchable shaft couplings - Google Patents

Abstract

832,587. Friction clutches. DAIMLERBENZ A.G. Jan. 17, 1958 [Jan. 17, 1957], No. 1726/58. Class 80 (2). In an axially engaged clutch having a friction synchronising ring to prevent full engagement until synchronism, the axially movable clutch part is connected to an axially fixed part by axial faces during disengagement and thrust producing faces during engaging conditions. A driving clutch member 10 is connected by camming balls 14 to a disc 11 to form a torsional vibration damper and/or an overload release coupling; the disc 11 having an internal conical friction surface 31. The driven member of the clutch comprises an axially movable member 21 carrying a split synchronizing ring 28 formed with radial cam surfaces co-operating surfaces on the member 21 which is carried by a bearing 20 on a shift collar 19. The member 21 is connected to the driven shaft 9 through meshing radial dogs 22, 23 and a ring 24 axially fixed with respect to the shaft. The dogs 22, 23 have axial faces 25 and inclined faces 26, 27, or these latter faces may be combined into a curved surface. The member 21 also carries a conical ring 38 co-operating with balls 17, loaded by springs 15, carried in pockets in the disc 11. A light spring 41 urges the shift collar 19 towards the engaging position. To engage the clutch, the member 21 is moved axially by the collar 19, releasing the faces 25 and engaging the faces 26 to produce an augmenting thrust; the member 21 also carries the ring 28 into partial engagement with the surface 31 and causes the balls 17 to move outwards against the springs 15. Due to the lack of synchronism between the face 31 and ring 28, the ring 28 tends to rotate and thus allows the cam surfaces to prevent contraction of the ring until synchronism is reached. At this stage the ring 28 contracts and allows the member 21 to move to the fully engaged position at which the surfaces 27 are in contact to provide higher thrust for holding engagement. For automatic engagement, the engine is accelerated until the balls 17 move outwards against springs 15 and the thrust of the spring 41 is then sufficient to initiate engagement. Decrease in engine speed allows the balls 17 to move the member 21 to a disengaged position. In a modification, the split ring 28 is replaced by a two-part synchronising ring having axially camming surfaces held together by hairpin springs. In a second embodiment the driven member in a conventional torsionally damped friction clutch plate, the synchronizing camming surfaces being formed on the rear of the pressure plate and on the pressure plate carrier.