Patent US4026384A successfully refreshed from Google Patents.
US4026384A
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Reconstituted mica acoustic diaphragm
Assignee: Okabe Mica Co Ltd
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Filing: 1975-11-24
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Granted: 1977-05-31
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Expires: 1995-11-24
Abstract
Abstract An acoustic diaphragm composed essentially of a flat, cone-like or dome-like reconstituted mica paper of fine scaly mica flakes and an organic polymeric binder impregnated in the mica paper. The diaphragm has a density of 1.3 to 2.3 g/cm 3 and a Young's modulus of 6 × 10 10 to 3 × 10 12 dyne/cm 2 .
Inventors
- 👤 Kenzabro Yamachika
- 👤 Ituro Sonoda
- 👤 Ichimatsu Kishimoto
- 👤 Masaaki Matsushima
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 13:47
CPC Classifications
H; H04; H04R; H04R31/00; H04R31/003; G; G10; G10K; G10K13/00; H04R7/00; H04R7/02
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
112 words
A loudspeaker diaphragm made of a mica sheet and consisting essentially of a number of scaly flakes with a size of 8 to 400 mesh of a mica selected from the group consisting of natural mica, synthetic mica and partially dehydrated natural mica and an organic polymeric binder, said scaly mica flakes having their cleavage planes (001 plane) oriented parallel to the surface of the mica sheet and being bonded to one another through said binder at their cleavage planes (001 plane), and said mica sheet having a density of 1.3 to 2.3 g/cm 3 and a Young's modulus of 6× 10 10 dyne/cm 2 to 3× 10 12 dyne/cm 2 .
Claim 2
Dependent Claim
112 words
A loudspeaker diaphragm made of a mica sheet and consisting essentially of a number of scaly flakes with a size of 8 to 400 mesh of a mica selected from the group consisting of natural mica, synthetic mica and partially dehydrated natural mica and an organic polymeric binder, said scaly mica flakes having their cleavage planes (001 plane) oriented parallel to the surface of the mica sheet and being bonded to one another through said binder at their cleavage planes (001 plane), and said mica sheet having a density of 1.3 to 2.3 g/cm 3 and a Young's modulus of 6× 10 10 dyne/cm 2 to 3× 10 12 dyne/cm 2 .
Claim 3
Dependent Claim
27 words
The loudspeaker diaphragam of claim 1 wherein the content of said binder is 5 to 50% by weight based on the total weight of said mica sheet.
Claim 4
Dependent Claim
13 words
The loudspeaker diaphragm according to claim 1, in the shape of a cone.
Claim 5
Dependent Claim
13 words
The loudspeaker diaphragm according to claim 1, in the shape of a dome.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1980-05-30 | 1980-11-29 | 1981-05-31 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-05-30 | 1984-11-29 | 1985-05-31 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-05-30 | 1988-11-29 | 1989-05-31 | $7700.00 | Window Closed / Lapsed |