Patent ID: 9025786
Filing Date: 2015-05-05
Classification: F01N,F16L,G10K

Abstract:
1. An active noise control system for an exhaust system of a combustion engine operated vehicle, comprising: an anti-sound control, which can be connected to an engine control of the vehicle; and a loudspeaker, which is connected to the anti-sound control for receiving control signals, wherein the loudspeaker is adapted to generate an anti-sound in a sound generator in response to a control signal received from the anti-sound control, wherein the sound generator can be fluidically connected to the exhaust system; wherein in the anti-sound control at least two characteristic curves are stored in order to at least partially cancel airborne sound conducted in the exhaust system by outputting the control signal to the loudspeaker, which characteristic curves cover different temperature ranges of the exhaust gas conducted in the exhaust system, which temperature ranges overlap one another by pairs or directly adjoin one another; and wherein the anti-sound control is further adapted to select a characteristic curve that is suitable for a respective temperature of the exhaust gas conducted in the exhaust system from the available characteristic curves by means of signals output by the engine control and to output control signals to the loudspeaker derived from the selected characteristic curve; the active noise control system further comprising: an error microphone, which is connected to the anti-sound control and can be arranged in a location of the exhaust system in the region of the fluid connection between sound generator and exhaust system, wherein the error microphone is adapted to measure sound in the interior of the exhaust system and to output a corresponding measurement signal to the anti-sound control; wherein the anti-sound control is adapted to determine by means of signals received from the error microphone through comparison with a threshold value if a selected characteristic curve is suitable for a respective temperature of the exhaust gas conducted in the exhaust system.