GB539062A - Improvements in and relating to variable velocity ratio gearing - Google Patents

Abstract

539,062. Variable-speed gearing. WYCLIFFE FOUNDRY CO., Ltd., and HEALEY, F. J. Feb. 23, 1940, No. 14918. Divided out of 529,506. [Class 80 (ii)] Relates to variable-speed gearing of the kind in which toothed wheels 24, Fig. 2, of different diameters, arranged in the form of a cone, are alternatively engaged by a displaceable toothed wheel 11 on a shaft inclined to the axis of the cone, and the wheels 24 are, as described in Specification 212,483, [Class 80 (ii)], provided with dog teeth for effecting a one-way driving connection with an adjacent wheel. In the arrangement described in the prior Specification, the dog teeth are so formed that the relative rotation between adjacent wheels, which occurs during the change of gear, causes the dog teeth to ride upon another, so as to move the wheels axially apart. According to the invention, the dog teeth are formed as shown in Fig. 13, so as to provide for an initial rotational movement bewteen adjacent wheels before the axial movement occurs. The teeth of the incoming wheel may thus come into alignment with the toothspaces of the sliding wheel, and harsh and delayed gear-changing is avoided. Flat surfaces 38 are left between the inclined faces 39 of the teeth and the abutting faces 37, so as to provide the lost motion. The apices of the teeth are preferably formed with flat surfaces. The diameter of the shaft carrying the cone-wheels is preferably increased by steps at intervals, in order to limit the movement of the wheels along the shaft.