Miniature loudspeaker and magnetic circuit having integrated air flow passage

摘要

The present invention relates to a miniature electro-acoustic transducer comprising a magnetic circuit comprising a permanent magnet assembly adapted to generate a magnetic flux in an air gap, the magnetic circuit comprising a magnetically permeable yoke having one or more air flow passages arranged therein, the one or more air flow passages being in fluidic communication with the air gap to allow pressurised and/or heated air trapped blow a diaphragm of the transducer to be guided to the exterior of the magnetic circuit via said one or more air flow passages. The transducer further comprises a voice coil positioned in the air gap, the voice coil being operatively connected to the diaphragm. The one or more air flow passages are arranged in the yoke so as to guide pressurised and/or heated air in a plane being substantially perpendicular to the direction of movement of the diaphragm.