Acoustic transducer having reduced thickness

• US 20030190053A1
• Filed: 04/09/2002
• Published: 10/09/2003
• Est. Priority Date: 04/09/2002
• Status: Active Grant

• Current Assignee: Sonion Nederland BV
• Original Assignee: Sonionmicrotronic Nederland B.V.
• Inventors: van Halteren, Aart Z.
• Granted Patent: US 7,190,803 B2
• Time in Patent Office: Days
• US Class Current: 381/418
• CPC Class Codes: H04R 11/02 Loudspeakers
• CPC Class Codes: H04R 25/00 Deaf-aid sets , i.e. electro-acoustic or electro-mechanical hearing aids; Electric tinnitus maskers providing an auditory perception electrical stimulation of auditory nerves to promote the auditory function A61N1/36038; optical stimulation of auditory nerves to promote the auditory function A61N5/0622
• CPC Class Codes: H04R 31/006 Interconnection of transducer parts of diaphragm and outer suspension by moulding H04R31/003

Abstract

A transducer for a hearing aid includes a housing, a relatively thin membrane having a free end suspended in the housing for vibration in response to a motor. The motor has a coil and a magnet assembly, the coil being mounted in the housing beneath the membrane; the magnet assembly being mounted in the housing coaxially with the coil and to one edge of the membrane.

Claims

1. A transducer for a hearing aid, said transducer comprising:

a housing, a relatively thin membrane suspended in said housing for vibration in response to a motor having a free end, said motor comprising a coil and a magnet assembly, said coil being mounted in said housing beneath said membrane;

said magnet assembly being mounted in said housing coaxially with said coil and to one edge of said membrane.

2. The transducer of claim 1 wherein said housing has a case and a cover and wherein said membrane is suspended beneath said cover.

3. The transducer of claim 2 wherein said cover has a through opening and wherein said magnet assembly includes a magnet and a magnet housing surrounding said magnet, a top portion of said magnet housing extending into said opening in said cover.

4. The transducer of claim 1 wherein said magnet assembly is laterally spaced from an end of said coil, and further including an armature extending through said coil and said magnet and a drive pin having one end coupled to said armature and extending through a space defined between said coil and said magnet assembly and having a second end coupled with said membrane.

5. The transducer of claim 3 wherein said magnet is constructed of a rare earth magnet material, such as neodymium or samarium.

6. The transducer of claim 1 wherein said coil comprises an oval coil.

7. The transducer of claim 4 wherein said drive pin extends through said membrane and is bent at an acute angle relative to a surface of said membrane, and wherein a quantity of adhesive is introduced between said membrane surface and said drive pin.

8. The transducer of claim 1 wherein said membrane is hingedly coupled with said housing.

9. The transducer of claim 8 wherein said membrane has a through opening through which said drive pin extends.

10. The transducer of claim 8 wherein said membrane has an edge recess through which said drive pin extends.

11. The transducer of claim 1 wherein said coil and said magnet assembly are mounted to a printed circuit board.

12. The transducer of claim 1 wherein said housing comprises a case and a cover, and further including flanges formed at lateral edges of said membrane and a quantity of damping paste applied between said flanges and each of a pair of respective opposed inwardly facing surfaces of said case.

13. The transducer of claim 12 wherein said membrane flange on one lateral edge is spaced from the facing wall of said case by a distance greater than the flange on the other edge, wherein said flanges extend into said case and further including a cap applied over said damping paste and along both of the lateral edges of said membrane.

14. The transducer of claim 2 wherein said membrane is carried on a suspension foil, and wherein said suspension foil is clamped between said cover and said case.

15. The transducer of claim 14 wherein additional foil is interposed between said cover and said suspension foil along edges of said suspension foil which are clamped between said cover and said case.

16. The transducer of claim 14 wherein outer edges of said suspension foil are folded back to provide a double layer of foil along said edges prior to clamping said edges between said cover and said case.

35. The transducer of claim 11 wherein an end part of said printed circuit board extends outwardly of said housing to accommodate electrical connecting means.

36. The transducer of claim 35 wherein said electrical connecting means comprises a micro-socket connector.

38. The transducer of claim 1 wherein said one edge of said membrane is attached to said magnet assembly.

17. A dual transducer for a hearing aid, said dual transducer comprising a pair of transducers mounted in side-by-side abutting relation, each of said transducers comprising:

a housing, a relatively thin membrane having a free end suspended in said housing for vibration in response to a motor, said motor comprising a coil and a magnet assembly, said coil being mounted in said housing beneath said membrane;

said magnet assembly being mounted in said housing coaxially with said coil and to one edge of said membrane;

wherein each said housing comprises a case and a cover with said membrane being spaced beneath and parallel with said cover and wherein said transducers are mounted with said cases in congruently aligned and abutting condition.

18. The dual transducer of claim 17 wherein each transducer further includes a relatively rigid printed circuit board and wherein said magnet assembly and said coil are mounted on said printed circuit board.

19. The dual transducer of claim 17 wherein each of said transducers is matched with the other of said transducers according to predefined criteria.

20. The dual transducer of claim 19 wherein said predefined criteria includes magnetizing at least one of said transducers so that the sensitivities of both transducers match at a given frequency.

21. The dual transducer of claim 20 wherein said given frequency is not greater than 1 KHz.

39. The transducer of claim 17 wherein said one edge of said membrane is attached to said magnet assembly.

22. A transducer for a hearing aid, said transducer comprising:

a housing, a relatively thin membrane having a free end suspended in said housing for vibration in response to a motor, said motor comprising a coil and a magnet assembly, said coil being mounted in said housing beneath said membrane; and

an armature extending through said coil and said magnet assembly and a drive pin having one end coupled to said armature and having a second end coupled with said membrane;

wherein said drive pin extends through said membrane and is bent at an acute angle relative to a surface of said membrane, and wherein a quantity of adhesive is introduced between said membrane surface and said drive pin.

23. A transducer for a hearing aid, said transducer comprising:

a housing, a relatively thin membrane having a free end suspended in said housing for vibration in response to a motor, said motor comprising a coil and a magnet assembly, said coil being mounted in said housing beneath said membrane;

wherein said membrane is hingedly coupled with said housing.

24. The transducer of claim 23 and further including an armature extending through said coil and said magnet and a drive pin having one end coupled to said armature and having a second end coupled with said membrane.

25. The transducer of claim 24 wherein said membrane has a through opening through which said drive pin extends.

26. The transducer of claim 24 wherein said membrane has an edge recess through which said drive pin extends.

27. A transducer for a hearing aid, said transducer comprising:

a housing, a relatively thin membrane having a free end suspended in said housing for vibration in response to a motor, said motor comprising a coil and a magnet assembly, said coil being mounted in said housing beneath said membrane; and

a printed circuit board mounted in said housing;

wherein said coil and said magnet assembly are mounted to said printed circuit board.

28. A transducer for a hearing aid, said transducer comprising:

a housing, a relatively thin membrane having a free end suspended in said housing for vibration in response to a motor, said motor comprising a coil and a magnet assembly, said coil being mounted in said housing beneath said membrane;

wherein said housing comprises a case and a cover, and further including flanges formed at lateral edges of said membrane and a quantity of damping paste applied between said flanges and each of a pair of respective opposed inwardly facing surfaces of said case.

29. The transducer of claim 28 wherein said membrane flange on one lateral edge is spaced from the facing wall of said case by a distance greater than the flange on the other edge, wherein said flanges extend into said case and further including a cap applied over said damping paste and along both of the lateral edges of said membrane.

30. A transducer for a hearing aid, said transducer comprising:

a housing, a relatively thin membrane suspended in said housing for vibration in response to a motor, said motor comprising a coil and a magnet assembly, said coil being mounted in said housing beneath said membrane;

wherein said housing has a case and a cover and wherein said membrane is suspended beneath said cover;

wherein said membrane is carried on a suspension foil, and wherein said suspension foil is clamped between said cover and said case.

31. The transducer of claim 30 wherein additional foil is interposed between said cover and said suspension foil along edges of said suspension foil which are clamped between said cover and said case.

32. The transducer of claim 30 wherein outer edges of said suspension foil are folded back to provide a double layer of foil along said edges prior to clamping said edges between said cover and said case.

33. A transducer for a hearing aid, said transducer comprising a housing, a relatively thin membrane having a free end suspended in said housing for vibration in response to a motor, said motor comprising a coil and a magnet assembly, said coil being mounted in said housing beneath said membrane;

said magnet assembly being mounted in said housing coaxially with said coil and to one edge of said membrane, such that said membrane extends over said coil, but not over said magnet assembly.

37. The transducer of claim 33 wherein said one edge of said membrane is attached to said magnet assembly.

34. A dual transducer for a hearing aid, said dual transducer comprising a pair of transducers mounted in side-by-side abutting relation, each of said transducers comprising:

a housing, a relatively thin membrane having a free end suspended in said housing for vibration in response to a motor, said motor comprising a coil and a magnet assembly, said coil being mounted in said housing beneath said membrane;

said magnet assembly being mounted in said housing coaxially with said coil and to one edge of said membrane, such that said membrane extends over said coil, but not over said magnet assembly;

wherein each said housing comprises a case and a cover with said membrane being spaced beneath and parallel with said cover and wherein said transducers are mounted with said cases in congruently aligned and abutting condition.

40. The transducer of claim 34 wherein said one edge of said membrane is attached to said magnet assembly.