GB1419334A - Friction wheel drive - Google Patents

Abstract

1419334 Variable-speed gear WAHLI FRERES SA 6 Aug 1973 [15 Aug 1972] 37290/73 Heading F2D Output speeds varying steplessly from zero in each direction are provided by an intermediate member 19 rotatable about an axis spaced from and lying in a plane including the axes of aligned input and output shafts 4, 6, and having part-spherical heads 20, 21 of equal or unequal radii of curvature r, R, contacting coned or part-spherical surfaces 11a, 12a on input and output discs 11, 12, the intermediate member 19 being journalled in a block 16 pivotal about a transverse axis through the centre of curvature of the heads 20, 21, to produce forward and reverse speeds on each slide of a zero setting in which the axis of rotation of the intermediate member 19 passes through the friction surface 12a of the output disc 12, the means for controlling such pivotal movement being located between the tangential planes of the heads 20, 21. As shown the output disc 12 is connected to the output shaft by a cam-and-ball torqueresponsive axial thrust device 13, which may be arranged between the heads 20, 21 of the intermediate member. In Figs. 3 and 4, not shown, the output cam-and-ball device is replaced by a spring, in which case the torque produces a variable compression of the spring and hence torque-response. In Fig. 2, not shown, the intermediate member 19 is pivotally adjusted by a direct-acting hand-knob (43) locked by a set-knob (44). Electric, pneumatic, hydraulic or mechanical remote control may be used.