Patent ID: 7151840

Claim:
A miniaturized sound transducer operating in accordance with the electro-dynamic principle, wherein the sound transducer comprises: a housing of deep drawn sheet metal having a bottom; a magnet system comprising a magnet; a diaphragm provided with a coil; wires extending from the coil to contacts; wherein the housing has an outer diameter of maximally 20 mm; wherein the housing is comprised of thin sheet steel having an average thickness of maximally 0.2 mm; wherein the magnet system has a lower pole piece and an upper pole piece; wherein the upper and lower pole pieces are comprised of sheet steel having a thickness of at least 1.5 times an average thickness of the bottom of the housing and wherein the magnet system is composed of the lower pole piece and the bottom of the housing which are in contact with one another over entire surfaces thereof which face each other.