GB1473844A - Synchromesh mechanisms - Google Patents

Abstract

1473844 Synchronizing clutches VAUXHALL MOTORS Ltd 2 May 1974 [21 June 1973] 29504/73 Heading F2C In a synchronizing clutch for a vehicle gearbox the synchronizing friction force between frusto-conical surfaces of a synchronizing ring and a gear to be clutched to a shaft is supplemented by an additional friction clutch energized by the friction force between ring and gear. In the embodiment illustrated in Figs. 1 and 3 axial baulk pins 24 are provided, mounted in a cage 18, initial movement of a coupling sleeve 14 moving the pins 24 and cage 18 through a ball 20 (acted on by a ridge 22) and a spring, the cage pressing a synchronizing ring 16 against a frusto-conical surface of a gear 10. The ring 16 has a clutch element 26 splined to it, a further clutch element 34 being slidably mounted on pins 24. The drag torque between the ring 16 and the gear 10 causes relative rotation of clutch elements 26, 34 to thereby cause cam surfaces 30, 32 of the elements (Fig. 3) to separate them and cause them to engage the gear 10 through surfaces 36, 38 to provide the additional synchronizing action. A spring 39 biases the clutch elements together so that they are inoperative when synchronization is complete and movement of the pins 24 circumferentially permits axial movement of sleeve 14, and clutch engagement. Rollers could also be used in the embodiment shown to reduce friction between the cam surfaces 30, 32, and the spring 39 may be replaced by a series of compression springs.