Abstract: A resonator (1, 1?, 1?) for reducing airborne noise has at least one first ring-shaped chamber (2, 2?, 2?) arranged between an inlet piece (6, 6?) and an outlet piece (7, 7?). An inner tube (3) or inner tube pieces (4, 4?, 5) are arranged between the inlet piece (6, 6?) and outlet piece (7, 7?) and have wall apertures (18, 19, 28, 28?, 29, 29?, 30, 30?) as a connection to the adjacent ring-shaped chamber (2, 2?, 2?). The first ring-shaped chamber (2, 2?, 2?) is divided by at least one radially encircling dividing rib (13, 13?, 13?) into at least two sub-chambers (14, 14?, 14?, 15, 15?, 15?). The dividing rib (13, 13?, 13?) has a free end that, relative to the wall that is adjacent in a radial direction, forms an encircling annular space (16) for receiving an air layer that co-resonates in steady-state.

Abstract: A resonator (1, 1?, 1?) for reducing airborne noise has at least one first ring-shaped chamber (2, 2?, 2?) arranged between an inlet piece (6, 6?) and an outlet piece (7, 7?). An inner tube (3) or inner tube pieces (4, 4?, 5) are arranged between the inlet piece (6, 6?) and outlet piece (7, 7?) and have wall apertures (18, 19, 28, 28?, 29, 29?, 30, 30?) as a connection to the adjacent ring-shaped chamber (2, 2?, 2?). The first ring-shaped chamber (2, 2?, 2?) is divided by at least one radially encircling dividing rib (13, 13?, 13?) into at least two sub-chambers (14, 14?, 14?, 15, 15?, 15?). The dividing rib (13, 13?, 13?) has a free end that, relative to the wall that is adjacent in a radial direction, forms an encircling annular space (16) for receiving an air layer that co-resonates in steady-state.

Abstract: A wide-band damper is designed for charge air lines of an internal combustion engine with turbocharger. The wide-band damper has an inlet and an outlet. Proceeding from the inlet, at least three slot chambers are arranged axially in series. The slot chambers are dimensioned for different frequencies f1, f2 and f3. At least three gap chambers are provided, which are arranged axially in series and axially downstream of the at least three slot chambers. The gap chambers are dimensioned for different frequencies f6, f7 and f8. Each of the frequencies f1, f2 and f3 of the slot chambers is lower than each of the frequencies f6, f7 and f8 of the gap chambers.

Abstract: A disc damper for a charge air line of an internal combustion engine that has a turbocharger. The disc damper includes an inlet, an outlet, and at least one slit chamber disposed between the inlet and outlet. Starting from the inlet, at least two gap chambers are provided downstream of the slit chamber and disposed axially one after the other. At least one of the following features is fulfilled: a) the slit chamber has a radial inner dimension that changes in the circumferential direction and/or b) the slit chamber has axial inner dimensions that change in the circumferential direction, and/or at least one gap chamber comprises radial inner dimensions that change in the circumferential direction.

Abstract: A wide-band damper is designed for charge air lines of an internal combustion engine with turbocharger. The wide-band damper has an inlet and an outlet. Proceeding from the inlet, at least three slot chambers are arranged axially in series. The slot chambers are dimensioned for different frequencies f1, f2 and f3. At least three gap chambers are provided, which are arranged axially in series and axially downstream of the at least three slot chambers. The gap chambers are dimensioned for different frequencies f6, f7 and f8. Each of the frequencies f1, f2 and f3 of the slot chambers is lower than each of the frequencies f6, f7 and f8 of the gap chambers.

Abstract: In order to reduce the interior noise level in an automobile, the vibration excitation of the front region of the floor panel is reduced by means of localized gaps between front longitudinal members, on the one hand, and the floor panel, on the other hand, as well as through support of the longitudinal members by a cross member in an approximately middle region of the sill members only, whereas the vibration excitation of the rear region of the floor panel is increased, so that in the head region of the vehicle occupants airborne vibration components are present which in amplitudes as well as phases are suitable to extinguish one another by means of interference.