ELECTROMECHANIC TRANSDUCER, ESPECIALLY FOR MOUNTING IN THE INTAKE PIPE OF AN INTERNAL COMBUSTION ENGINE

摘要

The invention relates to a loudspeaker, especially for actively influencing the intake noise of an internal combustion engine. Said loudspeaker (10) has a mass (12) which is moved by means of a drive (13), and a membrane which acts as a spring. In addition, a pneumatic spring (16) supported in a fixed manner is mounted on the mass (12). The rigidity of the pneumatic spring (16) can be influenced by a change in the pressure in the partial volumes (19), enabling the loudspeaker to be detuned. A loudspeaker which is to be used in the intake pipe of an internal combustion engine can be given smaller dimensions in the design stage thereof, as the detuning of the loudspeaker can shift the resonance frequency thereof.