IP Library Granted Patent US 8,406,452
Granted Patent B2
US 8,406,452 · App. 12/602,017 · Granted Mar 26, 2013

Diaphragm for speaker, speaker using the diaphragm, and system using the speaker

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Quick Facts
Patent No.
US 8,406,452
App. No.
12/602,017
Granted
Mar 26, 2013
Kind
B2
Abstract

A loudspeaker diaphragm contains polylactic acid, and bamboo charcoal mixed in the polylactic acid. The diaphragm does not affect environment and provides a loudspeaker with high sound quality.

Claims (68)

1. Loudspeaker diaphragm fibers comprising:

polylactic acid; and bamboo charcoal mixed in the polylactic acid.

2. Loudspeaker diaphragm fibers according to claim 1 , further comprising bamboo fiber.

3. Loudspeaker diaphragm fibers according to claim 2 , wherein the bamboo fiber has a fiber length not less than 0.2 mm and not more than 3 mm.

4. Loudspeaker diaphragm fibers according to claim 2 , wherein a content of the bamboo fiber is not less than 5 wt. % and not more than 55 wt. %.

5. Loudspeaker diaphragm fibers according to claim 2 , wherein the bamboo fiber includes microfibrillated bamboo fiber having an average fiber diameter of not more than 10 μm.

6. Loudspeaker diaphragm fibers according to claim 2 , wherein the bamboo fiber includes bamboo powder.

7. Loudspeaker diaphragm fibers, comprising:

polylactic acid; and a bamboo fiber mixed in the polylactic acid, wherein the bamboo fiber includes microfibrillated bamboo fiber.

8. Loudspeaker diaphragm fibers according to claim 7 , wherein the microfibrillated bamboo fiber has an average fiber diameter not more than 10 μm.

9. Loudspeaker diaphragm fibers according to claim 7 , wherein the bamboo fiber has a fiber length not less than 0.2 mm and not more than 3 mm.

10. Loudspeaker diaphragm fibers according to claim 7 , wherein the bamboo fiber includes bamboo powder.

11. Loudspeaker diaphragm fibers according to claim 7 , wherein a content of the bamboo fiber is not less than 5 wt. % and not more than 60 wt. %.

12. Loudspeaker diaphragm fibers according to claim 7 , further comprising reinforcing material.

13. Loudspeaker diaphragm fibers according to claim 7 , wherein the reinforcing material contains material made from plant.

14. Loudspeaker diaphragm fibers according to claim 7 , wherein the reinforcing material contains bamboo charcoal.

15. Loudspeaker diaphragm fibers, comprising:

first resin made from bamboo fibers, natural mineral mixed in the first resin,

plant fiber mixed in the first resin, carbonized material mixed in the first resin,

wherein the carbonized material comprises bamboo charcoal.

16. Loudspeaker diaphragm fibers according to claim 15 , wherein the first resin comprises polylactic acid.

17. Loudspeaker diaphragm fibers according to claim 15 , wherein the natural mineral comprises at least one of mica and talc.

18. Loudspeaker diaphragm fibers according to claim 15 , wherein the plant fiber comprises bamboo fiber.

19. Loudspeaker diaphragm fibers according to claim 18 , wherein the bamboo fiber has a fiber length not less than 0.2 mm and not more than 5 mm.

20. Loudspeaker diaphragm fibers according to claim 18 , wherein a content of the bamboo fiber is not less than 5 wt. % and not more than 55 wt. %.

21. Loudspeaker diaphragm fibers according to claim 18 , wherein the bamboo fiber comprises microfibrillated bamboo fiber having an average diameter not more than 10 μm.

22. Loudspeaker diaphragm fibers according to claim 18 , wherein the bamboo fiber contains bamboo powder.

23. Loudspeaker diaphragm fibers according to claim 15 , further comprising second resin made from petroleum.

24. Loudspeaker diaphragm fibers according to claim 23 , wherein the second resin includes thermoplastic resin.

25. Loudspeaker diaphragm fibers according to claim 24 , wherein the second resin comprises polypropylene.

26. Loudspeaker diaphragm fibers comprising:

base resin including resin made from bamboo fibers, and olefin resin; and

bamboo fiber mixed in the base resin, a carbon charcoal mixed in the base resin.

27. Loudspeaker diaphragm fibers according to claim 26 , wherein the resin comprises polylactic acid.

28. Loudspeaker diaphragm fibers according to claim 26 , wherein the olefin resin comprises polypropylene.

29. Loudspeaker diaphragm fibers according to claim 26 , wherein the bamboo fiber has a fiber length not less than 0.2 mm and not more than 5 mm.

30. Loudspeaker diaphragm fibers according to claim 26 , wherein a content of the bamboo fiber is not less than 5 wt. % and not more than 55 wt. %.

31. Loudspeaker diaphragm fibers according to claim 26 , wherein the bamboo fiber contains microfibrillated bamboo fiber having an average fiber diameter not more than 10 μm.

32. Loudspeaker diaphragm fibers according to claim 26 , wherein the bamboo fiber includes bamboo powder.

33. Loudspeaker diaphragm fibers according to claim 26 , further comprising reinforcing material mixed in the base resin.

34. Loudspeaker diaphragm fibers according to claim 33 , wherein the reinforcing material is natural mineral.

35. Loudspeaker diaphragm fibers according to claim 34 , wherein the reinforcing material is one of mica and talc.

36. Loudspeaker diaphragm fibers according to claim 33 , wherein the reinforcing material comprises polylactic acid.

37. A loudspeaker diaphragm comprising the loudspeaker diaphragm fibers according to claim 1 .

38. A loudspeaker diaphragm comprising the loudspeaker diaphragm fibers according to claim 2 .

39. A loudspeaker diaphragm comprising the loudspeaker diaphragm fibers according to claim 7 .

40. A loudspeaker diaphragm comprising the loudspeaker diaphragm fibers according to claim 15 .

41. A loudspeaker diaphragm comprising the loudspeaker diaphragm fibers according to claim 26 .

42. A loudspeaker comprising:

a loudspeaker diaphragm according to claim 37 ; a voice coil connected to the loudspeaker diaphragm; and a magnetic circuit for generating a magnetic flux crossing the voice coil.

43. A system comprising:

a loudspeaker according to claim 42 ; and a case having the loudspeaker mounted thereto.

44. A loudspeaker comprising:

a loudspeaker diaphragm according to claim 39 ; a voice coil connected to the loudspeaker diaphragm; and a magnetic circuit for generating a magnetic flux crossing the voice coil.

45. A loudspeaker comprising:

a loudspeaker diaphragm according to claim 40 ; a voice coil connected to the loudspeaker diaphragm; and a magnetic circuit for generating a magnetic flux crossing the voice coil.

46. A loudspeaker comprising:

a loudspeaker diaphragm according to claim 41 ; a voice coil connected to the loudspeaker diaphragm; and a magnetic circuit for generating a magnetic flux crossing the voice coil.

47. A loudspeaker comprising:

a loudspeaker diaphragm according to claim 38 ; a voice coil connected to the loudspeaker diaphragm; and a magnetic circuit for generating a magnetic flux crossing the voice coil.

48. A system comprising:

a loudspeaker according to claim 47 ; and a case having the loudspeaker mounted thereto.

49. A system comprising:

a loudspeaker according to claim 45 ; and a case having the loudspeaker mounted thereto.

50. A system comprising:

a loudspeaker according to claim 44 ; and a case having the loudspeaker mounted thereto.

51. A system comprising:

a loudspeaker according to claim 46 ; and a case having the loudspeaker mounted thereto.

Assignments (2)
CORRECTIVE ASSIGNMENT TO CORRECT THE ERRONEOUSLY FILED APPLICATION NUMBERS 13/384239, 13/498734, 14/116681 AND 14/301144 PREVIOUSLY RECORDED ON REEL 034194 FRAME 0143. ASSIGNOR(S) HEREBY CONFIRMS THE ASSIGNMENT. Recorded Dec 24, 2020
From: PANASONIC CORPORATION
To: PANASONIC INTELLECTUAL PROPERTY MANAGEMENT CO., LTD.
Reel/Frame 056788/0362 →
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Nov 10, 2014
From: PANASONIC CORPORATION
To: PANASONIC INTELLECTUAL PROPERTY MANAGEMENT CO., LTD.
Reel/Frame 034194/0143 →