Microphone with internal damping

• US 20060093167A1
• Filed: 10/29/2004
• Published: 05/04/2006
• Est. Priority Date: 10/29/2004
• Status: Active Grant

• Current Assignee: Sonion Nederland BV
• Original Assignee: Sonion Nederland BV
• Inventors: Mogelin, Raymond, Dubbeldeman, Eddy, Appel, Ronald
• Granted Patent: US 7,415,121 B2
• Time in Patent Office: Days
• US Class Current: 381/176
• CPC Class Codes: H04R 19/016 for microphones
• CPC Class Codes: H04R 19/04 Microphones H04R19/01 takes precedence
• 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

Abstract

Method and apparatus are disclosed for damping the resonance frequency in a microphone. The method and apparatus of the invention involve providing an elastomeric frame to support the backplate. The elastomeric frame forms a substantially air tight seal around the backplate. A hole is formed in the backplate and a cover having an opening therein is placed over the hole in the backplate. The frequency response of the microphone may then be controlled by precisely controlling the size, shape, and/or location of the opening in the cover overlaying the hole. The cover may also serve as an electrical contact to other components in the microphone.

Claims

1. A microphone, comprising:

a housing;

a diaphragm mounted in said housing;

a backplate mounted substantially parallel to and spaced apart from said diaphragm, said backplate having at least one hole through said backplate; and

a cover covering up said at least one hole in said backplate, said cover having at least one opening through said cover, said at least one opening having a predetermined size, shape, and/or location to control a frequency response of said microphone.

2. The microphone according to claim 1, further comprising a support frame surrounding a circumference of said backplate, said support frame forming an airtight seal with said backplate.

3. The microphone according to claim 2, wherein said support frame is made of an elastomeric material.

4. The microphone according to claim 3, wherein said elastomeric material includes rubber and silicon.

5. The microphone according to claim 1, wherein said cover resides within said backplate.

6. The microphone according to claim 1, wherein said cover resides on top of said backplate.

7. The microphone according to claim 1, wherein said at least one opening in said cover has a substantially rectangular shape.

8. The microphone according to claim 1, wherein said cover includes a clip portion extending away from said backplate at an angle, said clip portion providing a spring-load for said cover.

9. The microphone according to claim 7, wherein said clip portion provides an electrical connection between said backplate and other components in said microphone.

10. The microphone according to claim 1, wherein said backplate includes a stub protruding from said backplate and said cover includes a lug formed therein, said lug braced against said stub to help keep said cover in place.

11. The microphone according to claim 1, wherein said backplate includes a stub protruding from said backplate and said cover includes a backing formed thereon, said backing buttressed against said stub to help keep said cover in place.

12. The microphone according to claim 1, wherein said cover is adhered to said backplate to help keep said cover in place.

13. The microphone according to claim 1, wherein said cover is welded to said backplate to help keep said cover in place.

15. The method according to claim 12, further comprising forming a substantially airtight seal around said backplate.

16. The method according to claim 12, further comprising securing said cover to said backplate.

17. The method according to claim 16, wherein said cover is pressed to said backplate.

18. The method according to claim 16, wherein said cover is adhered to said backplate.

19. The method according to claim 16, wherein said cover is welded to said backplate.

20. The method according to claim 16, wherein said cover is wedged on said backplate.

21. The method according to claim 16, wherein cover is fitted into said backplate.

14. A method of damping a frequency response of a microphone, said microphone having at least a housing, a diaphragm mounted in said housing, and a backplate mounted in said housing at a known location relative to said diaphragm, said method comprising:

creating at least one hole through said backplate; and

covering up said hole with a cover such that at least one opening having a predetermined size, shape, and/or location remains over said at least one hole;

wherein said frequency response of said microphone is dampened based on said predetermined size, shape, and/or location of said at least one opening.

22. A mechanism for damping a frequency response of a microphone, comprising:

a backplate mounted in said microphone, said backplate having an inner wall defining a hole through a middle portion of said backplate; and

a cover covering up said hole in said backplate, said cover having an interior wall defining an opening through a middle portion of said cover, said opening having a predetermined size, shape, and/or location for allowing air to escape through said opening.

23. The mechanism according to claim 22, wherein said cover resides within said backplate.

24. The mechanism according to claim 22, wherein said cover resides on top of said backplate.

25. The mechanism according to claim 22, wherein said cover includes a clip portion extending away from said backplate at an angle, said clip portion providing a spring-load for said cover.

26. The mechanism according to claim 25, wherein said clip portion provides an electrical connection between said backplate and other components in said microphone.

27. The mechanism according to claim 22, wherein said backplate includes a stub protruding from said backplate and said cover includes a lug formed therein, said lug braced against said stub to help keep said cover in place.

28. The mechanism according to claim 22, wherein said backplate includes a stub protruding from said backplate and said cover includes a backing formed thereon, said backing buttressed against said stub to help keep said cover in place.

29. A method of manufacturing a microphone, said microphone having a housing, a diaphragm, and a backplate, comprising:

a

lancing a hole through said backplate;

surrounding said backplate with a support frame, said support frame forming a substantially airtight seal around said backplate;

mounting said backplate in said housing; and

covering up said hole in said backplate with a cover, said cover having an interior wall defining an opening through said cover, said opening having a predetermined size, shape, and/or location to control a frequency response of said microphone.

30. The method according to claim 29, further comprising electrically connecting said backplate to other components in said microphone using said cover.

31. The method according to claim 30, wherein said diaphragm, said backplate, said support frame, said cover, and said other components form a subassembly, further comprising mounting said subassembly in said housing of said microphone.

32. The method according to claim 29, further comprising wedging said cover on said backplate to help keep said cover in place.

33. The method according to claim 29, further comprising pressing said cover to said backplate to help keep said cover in place.

34. The method according to claim 29, further comprising disposing said cover in said backplate to help keep said cover in place.

35. A microphone, comprising:

a housing;

a diaphragm mounted in said housing;

a backplate mounted in said housing at a known location relative to said diaphragm;

an electrical-contact element for carrying signals from said backplate, said electrical-contact element providing an acoustic feature for controlling a frequency response of said microphone.

36. The microphone according to claim 35, wherein said acoustic feature is an opening having a predetermined size, shape, and/or location in said electrical-contact element.

37. The microphone according to claim 36, wherein said predetermined shape of said opening is substantially rectangular.