Combustion engine air-intake control during engine braking - involves adjustments of mixt. intake and exhaust to obtain max. engine braking as soon as road wheels are braked

摘要

The running conditions are evaluated (10) from measurements of brake pedal position, road speed and gradient for operation of a controller (11) acting on the engine (12) through e.g. throttle flaps (13) with controllable bypass for idling, and exhaust valves (15) with fixed or variable timing. For max. fuel economy the engine is operated at min. braking torque until the brakes are applied to the vehicle, and is then throttled back to achieve max. engine braking. ADVANTAGE - Motor vehicles. Air intake during engine braking is independent of fuel intake so that engine control is adapted optimally to running conditions.