Attenuating tip for hearing aid
A hearing aid includes a speaker in a tip that is located in an ear canal. The tip includes a coupling, a retainer that mechanically engages the coupling, and a sleeve axially surrounding the retainer. The retainer attenuates lower frequencies than are attenuated by the sleeve. The sleeve is preferably a foam rubber and the retainer is preferably a composite material. A flange on the retainer reflects sound back into the sleeve for additional attenuation. It has been discovered that operation is improved if the outside diameter of the sleeve and the outside diameter of the retainer are in the ratio of approximately 1.75:1.
1. A hearing aid including an earpiece, wherein the earpiece is located in an ear canal during use, characterized in that the earpiece includes:
a coupling containing a speaker;
a retainer that mechanically engages the coupling, the retainer being formed separately from the coupling, and the retainer being formed of a composite material including an organic carrier and an inorganic filler, wherein the retainer has a first end for mechanically engaging the coupling and a second end opposite the first end thereof, the first end having a first outside diameter, and the second end having a second outside diameter, the first outside diameter being larger than the second outside diameter; and
a sleeve axially surrounding the retainer, the sleeve being formed of foam rubber; wherein said retainer and said sleeve attenuate different ranges of audio frequency;
wherein said sleeve has an outside diameter, a, and the first end of said retainer has an outside diameter, b, and wherein said retainer includes a flange dividing the first end of the retainer from the second end of the retainer, the flange having a diameter, d, such that a >d >b, and said flange reflects sound approaching said flange from the second end of said retainer into said sleeve.
2. A hearing aid including an earpiece, wherein the earpiece is located in an ear canal during use, characterized in that the earpiece includes:
a coupling containing a speaker;
a retainer that mechanically engages the coupling, the retainer being formed separately from the coupling, and the retainer being formed of a composite material including an organic carrier and an inorganic filler, wherein the inorganic filler included within the composite material comprises barium sulphate; and
a sleeve axially surrounding the retainer, the sleeve being formed of foam rubber; wherein said retainer and said sleeve attenuate different ranges of audio frequency.