Patent US4439640A successfully refreshed from Google Patents.
US4439640A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Piezoelectric loudspeaker
Assignee: Murata Manufacturing Co Ltd
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Filing: 1981-12-31
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Granted: 1984-03-27
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Expires: 2001-12-31
Abstract
Abstract A piezoelectric loudspeaker thin plate-like shaped and using a piezoelectric ceramic plate for a sound-generating portion, which comprises a disc-shaped diaphragm formed of a metallic plate, a disc-shaped film using a material of a smaller Q-factor and formed about equal in diameter to the disc-shaped diaphragm, and a disc-shaped piezoelectric ceramic plate smaller in diameter than the disc-shaped diaphragm, these three members being stuck concentrically with each other, so that the integral-stuck member is supported at its outer peripheral portion to a frame.
Inventors
- 👤 Tadashi Takaya
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 02:25
CPC Classifications
H; H04; H04R; H04R17/00
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
93 words
A piezoelectric loudspeaker comprising: a disc-shaped diaphragm formed of a metallic plate; a disc-shaped film formed of a material having a smaller Q-factor than and substantially equal in diameter to said diaphragm; and a disc-shaped piezoelectric ceramic plate smaller in diameter than said diaphragm; said diaphragm, said film and said piezoelectric ceramic plate being adhered concentrically to each other so as to form an integral member with said piezoelectric ceramic plate located on the outside of said integral member; said integral member being supported at the outer peripheral portion thereof to a frame.
Claim 2
Dependent Claim
93 words
A piezoelectric loudspeaker comprising: a disc-shaped diaphragm formed of a metallic plate; a disc-shaped film formed of a material having a smaller Q-factor than and substantially equal in diameter to said diaphragm; and a disc-shaped piezoelectric ceramic plate smaller in diameter than said diaphragm; said diaphragm, said film and said piezoelectric ceramic plate being adhered concentrically to each other so as to form an integral member with said piezoelectric ceramic plate located on the outside of said integral member; said integral member being supported at the outer peripheral portion thereof to a frame.
Claim 3
Dependent Claim
18 words
A piezoelectric loudspeaker according to claim 1, wherein said disc-shaped diaphragm is formed of a thin brass plate.
Claim 4
Dependent Claim
19 words
A piezoelectric loudspeaker according to claim 1, wherein said disc-shaped film is formed of paper, polyethylene, or the like.
Claim 5
Dependent Claim
18 words
A piezoelectric loudspeaker according to claim 1, wherein said piezoelectric ceramic plate is adhered to said disc-shaped diaphragm.
Claim 6
Dependent Claim
18 words
A piezoelectric loudspeaker according to claim 1, wherein said piezoelectric ceramic plate is adhered to said disc-shaped film.
Claim 7
Dependent Claim
30 words
A piezoelectric loudspeaker according to claim 1, wherein said frame comprises a pair of annular frame members, said frame members sandwiching therebetween the outer peripheral portion of said integral member.
References Cited (Backward Citations)
DE3005708A1
Cited
US4368401A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1987-03-27 | 1987-09-26 | 1988-03-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-03-27 | 1991-09-26 | 1992-03-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-03-27 | 1995-09-26 | 1996-03-27 | $7700.00 | Window Closed / Lapsed |