1. A hearing aid intended for placement within an ear canal, comprising: a microphone, an amplifier and an electromechanical transducer coupled together in cascade and accommodated within a housing, and an extraction means for extracting the hearing aid from the ear canal, the input to the microphone being acoustically coupled to a sound entrance in the housing, wherein the extraction means comprises a hollow acoustic tube having one end located at the sound entrance of the housing and mechanically coupled to the housing so that the sound entrance is acoustically coupled to a channel in the acoustic tube.

2. A hearing aid as claimed in claim 1, wherein the tube is made of a flexible material.

3. A hearing aid as claimed in claim 2, wherein the other end of the acoustic tube comprises a gripping means.

4. A hearing aid as claimed in claim 1, wherein said acoustic tube is mechanically coupled to the housing by means of a fixed permanent mechanical coupling and the other end of the acoustic tube comprises a gripping means.

5. A hearing aid as claimed in claim 1, wherein said hollow tube extends outside of the housing and said electromechanical transducer comprises a telephone device.

6. A hearing aid as claimed in claim 1 wherein said housing is shaped so as to fit within an ear canal of a user of the hearing aid and the housing has a sound exit opening in a part thereof which is opposite to the part of the housing at which said sound entrance is located.

7. A hearing aid as claimed in claim 6 further comprising a further hollow tube located within the housing and arranged to couple a sound output of the electromagnetic transducer to the sound exit opening in the housing.

8. A hearing aid as claimed in claim 1 wherein the other end of the hollow tube is open so as to receive external sound waves intended for the input of the microphone.

9. An in-the-ear hearing aid comprising:

a housing having a sound entrance,

a microphone, an amplifier and an electromagnetic transducer electrically coupled together in cascade and mounted within said housing and with an input of the microphone acoustically coupled to the sound entrance of the housing, and

means for extracting the hearing aid from an ear canal, wherein said extracting means comprises a hollow tube forming an acoustic channel and with one end of the hollow tube mechanically coupled to the housing at the sound entrance so that the sound entrance is acoustically coupled to the acoustic channel in the hollow tube and is sealed off from sound waves other than those received by the acoustic channel in the hollow tube.

10. A hearing aid as claimed in claim 9 wherein the hollow tube extends outside of the housing in a line approximately straight back from the housing of the hearing aid thereby to extend the sound path from an acoustic output of the housing to an acoustic input of the hollow tube.

11. A hearing aid as claimed in claim 10 wherein the hollow tube is made of a flexible material.

12. A hearing aid as claimed in claim 10 wherein said acoustic input of the hollow tube comprises an opening in the other end of the hollow tube whereby the hollow tube provides a second function, suppression of acoustic feedback from said acoustic output of the housing to said opening in the other end of the hollow tube.

13. A hearing aid as claimed in claim 9 wherein the hollow tube is mechanically coupled to the housing in a fixedly attached manner and a sound output of the electromagnetic transducer is acoustically coupled to a sound output in the housing.

14. A hearing aid as claimed in claim 9 wherein an acoustic input end of the hollow tube comprises a gripping means to facilitate extraction of the hearing aid from an ear canal.

15. A hearing aid as claimed in claim 9 wherein the hollow tube is made of a flexible material.

16. A hearing aid as claimed in claim 9 wherein the hollow tube extends through the sound entrance in the housing and is mechanically coupled directly to the input of the microphone.

17. A hearing aid as claimed in claim 9 wherein the housing and hollow tube form an undivided unitary structure.

18. A hearing aid as claimed in claim 9 wherein said housing is shaped so as to fit within an ear canal of a user of the hearing aid and the housing has a sound exit opening which will face the tympanic membrane in the ear canal of the user when the housing is positioned within said ear canal.

19. A hearing aid as claimed in claim 9 wherein the other end of the hollow tube is open so as to receive external sound waves which will pass through said acoustic channel and said housing sound entrance to the input of the microphone.

The news come http://www.bossgoo.com