A sound generating device for a vehicle exhaust system has a housing, a sound generator located in the housing, a housing wall that comprises an opening for the sound generator, and a sound channel that extends in the housing. The sound generator is mounted to a shoulder section of the opening such that the opening is closed by the sound generator and a front side and a rear side of the sound generator are assigned to different sides of the opening. The sound channel acoustically connects the rear side of the sound generator with the front side of the sound generator. The opening and the sound generator comprise a central axis and the sound channel runs at least partially around the central axis.

A device includes a housing and a core configured to be secured within the housing. The core includes a microphone configured to detect a sound signal. The core also includes a control board configured to generate a noise-canceling sound signal based on the sound signal and a set of transfer functions. The core further includes a speaker configured to deliver the noise-canceling sound signal. The device also includes a fastener configured to connect the housing to an air filter of an intake vent of an enclosure of a power generation unit.

A sound generating device for a vehicle exhaust system has a housing, a sound generator located in the housing, a housing wall that comprises an opening for the sound generator, and a sound channel that extends in the housing. The sound generator is mounted to a shoulder section of the opening such that the opening is closed by the sound generator and a front side and a rear side of the sound generator are assigned to different sides of the opening. The sound channel acoustically connects the rear side of the sound generator with the front side of the sound generator. The opening and the sound generator comprise a central axis and the sound channel runs at least partially around the central axis.

A sound generating assembly for an exhaust system of an internal combustion engine of a motor vehicle includes a sound generator arranged within a sound generator housing. Furthermore, an outer contour of the sound generator housing has a connecting surface configured to be attached to a motor vehicle structure. The connecting surface is set off from a remaining surface of the outer contour.

A system (70) for actively controlling sound propagating through exhaust systems (40) includes a controller (90), a sound generator (30), in fluid communication with an exhaust system (40), and an actuator (20), inside the sound generator and receiving a controller control signal for generating sound inside the sound generator to reduce sound inside the exhaust system. The controller identifies an increased exhaust pressure inside the exhaust system based on signals output by an error microphone (50), a temperature sensor (51), an impedance measuring bridge (52), a bus system (53), or a water sensor (54). The controller interrupts a generation of the control signal and/or interrupts an output of the control signal to the at least one actuator and/or reduces a level of the control signal output to the at least one actuator by at least 30% or at least 60% upon determining a presence of an excessive exhaust gas pressure.

A valve unit with a valve having a valve shaft with a rotational axis. The valve unit including an actuator having an actuator shaft with a rotational axis. The valve unit includes a mechanical coupler for rotational coupling of the actuator shaft and the valve shaft. The mechanical coupler includes a rotational axis coinciding with the rotational axis of the actuator shaft and the rotational axis of the valve shaft. The valve unit includes a first rotational member coupled to the actuator shaft and a second rotational member coupled to the valve shaft. The valve unit includes a bridge element. The first and the second rotational members include slots for receiving engagement pins of the bridge element.

A device includes a housing and a core configured to be secured within the housing. The core includes a microphone configured to detect a sound signal. The core also includes a control board configured to generate a noise-canceling sound signal based on the sound signal and a set of transfer functions. The core further includes a speaker configured to deliver the noise-canceling sound signal. The device also includes a fastener configured to connect the housing to an air filter of an intake vent of an enclosure of a power generation unit.

An emission signature modification device for modifying an acoustic signature of an exhaust gas stream, including an exhaust gas guiding device that guides the exhaust gas stream in the flow direction thereof from an inlet area to an outlet area. An active acoustic emission modification device modifies the acoustic emission of the exhaust gas stream in predetermined operating states. If an actuator system of the active acoustic emission modification device is designed such that in a circumferential direction, the actuator system is surrounded by more than 30% of the guided exhaust gas stream, the actuating system can be protected against harmful influences from the environment by way of the exhaust gas guiding device on the one hand, and on the other hand, the required space signifier can be reduced as compared to a lateral, external arrangement of the actuating system.

Aspects of the present invention relate to noise modification systems of motor vehicles, and controllers and methods of use thereof.

A sound generation assembly unit, for an exhaust system of an internal combustion engine, includes a sound generation module (16) with a sound generation module housing to be arranged at an exhaust gas guide element (12) of the exhaust system (14). At least one loudspeaker unit (20) is arranged in the sound generation module housing (18). A rear volume module (30) includes a rear volume module housing (32) and a rear volume (34) formed in the rear volume module housing (32). The rear volume module housing (32) is connected or can be connected to the sound generation module housing (18) for the acoustic coupling of the rear volume (34) to the at least one loudspeaker unit (20).