Automatic gearbox control using feedback torque loop

摘要

A vehicle engine (1) is coupled through a torque converter (2) to an automatic gearbox (3), both engine and gearbox having control units (7, 8). A torque setpoint is generated (9) in response to a signal from the gearbox control unit, and this is compared with a signal from the drive shaft torque sensor (4), the difference signal then being input to the engine controller. Thus a feedback loop is formed. Variations include the use of an engine torque sensor (with or without a drive shaft torque sensor) and a microprocessor to compute the engine torque or drive shaft torque, thus replacing the appropriate sensor.