US Patent 7344201 Vehicle air braking systems

An electronic control system for the compressor of a vehicle air braking system, the control system having one or more inputs indicative of a vehicle operating state, and an output for determining whether a compressor is on-load or off-load, the system further including target means to calculate in real time a target pressure for a reservoir downstream of said compressor, said output being responsive to said target means. The target pressure may be varied in real time to suit vehicle running conditions and permits a small but significant reduction in vehicle fuel consumption by driving the compressor when the vehicle is likely to be coasting or slowing down.