GB803979A - Improvements in dog clutches fitted with synchronising devices - Google Patents

Abstract

803,979. Positive clutches. DAIMLERBENZ A.G. April 30, 1956 [May 2, 1.955], No. 13207/56. Class 80 (2). In a synchromeshed dog-clutch 17, 18 for a change-speed gear wherein a cone 20 frictionally engaging one clutch member 11 has limited circumferential play e at 27 on the other clutch member 13, 17 to permit movement to and from positions in which teeth 24 on the cone balk engaging movement of the dog teeth 16 of the member 17 towards the complementary dog teeth 18, the balk action is arranged unsymmetrically to offer a greater resistance for one direction of relative rotation (e.g. for downshifting into first ratio from second) then in the other (e.g. for engaging first ratio from rest). In one construction, Fig. 3, the circumferential play e is unsymmetrical with respect to the balk position so that in the direction of relative rotation x of the dogs 18, the dog teeth 16 are free to engage without balk resistance, whereas in the opposite direction the play e permits the balk teeth 24 to lie in the path of the dog teeth 16, causing balk resistance until synchronism is attained. In Figs. 5 to 7 (not shown), the play is symmetrical or otherwise, but the pointed butting ends of the balk teeth 24 and/or dog teeth 16 are inclined at different angles on opposite faces to offer different resistance according to the faces engaged and hence the direction of relative rotation. Initial axial pressure is transmitted to the friction cone 20 through a spring-loaded ball 33 and push-piece 34 carried in a groove in the shaftmember 13.