Vehicle transmissions with automatic safety override when in manual mode

Abstract

A vehicle transmission having a main drive clutch (14), a multi-ratio gearbox (12), a gear engaging mechanism (25) for engaging the operative ratio of the gearbox, and a manually operable gear selector (24) allowing the operator to manually select the operative ratio of the gearbox when the transmission is acting in a manual mode. An electronic control unit (36) is also included which controls the disengagement and engagement of the drive clutch at start-up and halting of the associated vehicle and during gear changes and which controls the operation of the gear engaging mechanism (25) in response to movements of the gear selector (24). The electronic control unit (36) is also arranged to override the gear ratio currently selected by the operator to select a more appropriate gear ratio for the current conditions if a predetermined operating condition occurs when in its manual mode. The transmission may also have an automatic mode of operation, the electronic control means (36) will then also determine which gear ratio is to be selected when the transmission is operating in its automatic mode.

Dependencies are inferred from the claim text.