GB1316121A - Differential mechanisms - Google Patents

Abstract

1316121 Differential gearing MECOTRON EUROPE (MALTA) Ltd 23 Sept 1970 [1 July 1969] 33220/69 Heading F2D A self-locking planetary bevel type differential gear includes helical worm gears 14, 16, 15, the tooth angles of which are such as to provide a semi-irreversible, i.e. semi-locking action under slip conditions to prevent spinning of a wheel on loss of traction. As shown, the planet bevels 10, 11 are keyed fast on radial shafts 12, 13 which are interconnected by the helical gear train 14, 16, 15 which allows normal differentiation but introduces internal friction when the load torque on the half-shafts 7, 8 becomes unbalanced, the helix angle of the centre helical control gear 16 being 45 degrees less half the kinetic friction angle viz. 42 degrees, 17 mins., and the helix angle of the helical gears 14, 15 being complementary (i.e. 47 degrees, 43 mins.) to that of the gear 16. The radial shafts 12, 13 are freely rotatably mounted in a housing 1 rotated by the usual crown wheel and are respectively connected to the half-shafts 7, 8 by the meshing planet and side bevel wheels 10, 5 and 11, 6, the helical gears 14, 15 on the radial shafts 12, 13 meshing the centre helical control gear 16 mounted on a freely rotatable shaft 17 radially arranged in the housing 1 at right-angles to the shafts 12, 13.