Patent ID: 6968069

Claim:
A tweeter comprising: a housing comprising a rear wall and a sidewall, the sidewall extending forwardly from the rear wall and terminating in all open front end, and wherein the rear wall and sidewall form a motor receiving space; a motor mounted in the motor receiving space of the housing, wherein the motor comprises a permanent magnet assembly and an annular gap extending around the permanent magnet assembly, wherein the motor is characterized by an air passage extending therethrough, wherein the motor comprises a yoke formed of a back panel and a sidewall extending forwardly of the back panel, the back panel and sidewall forming a magnet receiving space, wherein the magnet assembly comprises a first permanent magnet in the magnet receiving space of the yoke, a top plate receivable in the yoke over the first magnet, and a second permanent magnet positioned over the top plate, and wherein the at least one air passage through the motor comprises centrally positioned and aligned bores through the second magnet, the top plate, the first magnet and the back panel of the yoke; a diaphragm movably supported over the open end of the housing and forming a forward air chamber between the motor and the diaphragm, wherein the forward air chamber is continuous with the air passage through the motor and the annular gap around the magnet assembly; a voice coil assembly movably supported in the annular gap in the motor and operatively engaged with the diaphragm; wherein the voice coil assembly, the motor and the diaphragm are cooperatively adapted to reproduce high frequency sounds; an air chamber lateral to the motor and between the motor and the sidewall of the housing, and wherein the lateral air chamber is in communication with the air passage through the motor; wherein the second permanent magnet comprises an upper surface defining a plurality of radially extending grooves connecting the annular gap and the air passage through the motor.