GB191306632A - Improvements in Speed Transmission Gear. - Google Patents

Abstract

6632. Schoedelin, M. J. G. March 18. Friction and toothed gearing. - In speed transmission gear of the type in which motion is transmitted by means of rollers or disks from an outer ring to a central shaft or vice versa or from a central shaft to planet-pinions rolling within a fixed outer ring, additional inner rollers are provided between each pair of main rollers and between each main roller and the central shaft, the auxiliary rollers being maintained in position without bearings by flanges engaging grooves in the shaft. In the arrangement shown in Fig. 1, an outer ring 1, which may be driven by belt or toothed gearing or by a crank or pedal or other means, transmits motion to a central shaft 11 through main rollers 3, preferably three in number, mounted upon stationary spindles 7, and auxiliary inner rollers 8 arranged between the rollers 3 and between each roller 3 and the shaft 11. The rollers 3 engage between flanges 9, 2 on the auxiliary rollers 8 and in the ring 1 respectively. The flanges 9 on the rollers 8 engage annular grooves 10 in the shaft 11, whereby axial displacements of the rollers are prevented. The shaft 11 is held in position entirely by the parts which drive it, other bearings being dispensed with. The stationary spindles 7 are mounted in fixed side plates 4, flattened ends of the spindles engaging radial slots in the side plates to prevent rotation. Radial adjustment may be effected by means of cover-plates 7<a> which may be secured to the side plates 4 by screws 7<b> engaging slots in the plates 7<a>. The spindles 7 may serve as distance-pieces between the plates 4, or the plates may be secured by screws 5 to distance-pieces 6. The diameters of the parts are such that the ring 1 is slightly distorted to produce the required pressure to prevent slipping. The elements may be magnetized to increase the grip. In a modified form, the outer ring 1 is secured to the stationary casing of an electric motor, the central shaft 11 forms the driving-shaft of the motor and transmits rotation at a reduced speed to a coaxial two-speed pulley shaft carrying the rollers 3 which in this form have a hypocycloidal motion within the fixed ring 1. The friction gearing may be combined with toothed gearing to prevent slip. In this case, toothed elements of corresponding pitch diameters are secured to the respective frictional elements.