IMPROVEMENTS IN GEAR TRANSMISSIONS

摘要

Control means receives signals representing gear box input and output speeds from sensors in the gearbox which indicate when two gears to be engaged are running at substantially the same speed, and initiates engagement in response to a gear selection signal. The control means preferably acts on a constant mesh gearbox in which ratio change is effected by means of a hydraulically actuated selector and clutch. The gearbox preferably has discrete gear sets such as a three ratio set and a high/low range set. The system may act to reduce engine fuel supply during shift to achieve synchronism.