Patent ID: 7680294

Claim:
An acoustic transducer comprising: a magnetic circuit part; a voice coil operatively connected to the magnetic circuit part; a tubular casing accommodating the magnetic circuit part and the voice coil; an annular first support spring having an outer peripheral portion embedded and secured in the casing, the first support spring extending radially inward from the outer peripheral portion embedded and secured in the casing and having an inner peripheral portion abutting on and fixed to the magnetic circuit part; the casing having an annular recess provided at its lower end portion, the annular recess having a radial surface extending radially outward from an inner peripheral surface of the casing toward an outer peripheral surface of the casing; an annular second support spring having an outer peripheral portion abutting on and fixed to the lower end portion of the casing, the second support spring extending radially inward and having an inner peripheral portion abutting on and fixed to the magnetic circuit part; and a securing ring fitted in the annular recess at the lower end portion of the casing and secured to press the outer peripheral portion of the second support spring against the radial surface of the annular recess.