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US3973150A Expired / Lapsed US ⏱️ 0.0 years remaining

Rectangular, oriented polymer, piezoelectric diaphragm

Assignee: Pioneer Corp
•
Filing: 1975-02-12
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Granted: 1976-08-03
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Expires: 1995-02-12
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Abstract

Abstract A piezoelectric electro-acoustic transducer employing as a diaphragm a uniaxially stretched film of a shape having the major axis and the minor axis, wherein the expansion-contraction direction of the diaphragm, in which a piezoelectric constant is at a maximum, is substantially in parallel with the minor axis thereof, whereby the piezoelectric electro-acoustic transducer can provide a high converting efficiency, especially in the low frequency range.

Inventors

  • 👤 Masahiko Tamura
  • 👤 Kiyonori Iwama
  • 👤 Toshikazu Yoshimi

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-24 08:01
CPC Classifications
H; H04; H04R; H04R17/00; H04R17/005; Y; Y10; Y10S; Y10S310/00; Y10S310/80

Claims Analysis

Total Claims: 11
Claim 1
Independent Claim 173 words
A piezoelectric electro-acoustic transducer comprising: a piezoelectric diaphragm made of a high polymeric resin having its molecules uniaxially oriented, said diaphragm having a great anisotropy in the plane thereof and being of an elongate shape having a length dimension greater than its width dimension; a support means conforming in plan to said diaphragm such that its length correspondingly exceeds its width, such support means including a rigid perforate base plate behind said diaphragm, a resilient foam backing member sandwiched between the major central areas of said diaphragm and base plate in fixed relation to said base plate, and at least one opposed pair of elongate, stiff fixing members along opposed edges of said diaphragm for fixing said diaphragm edges with respect to said base plate; the resultant vector of the piezoelectric constants in the plane of said diaphragm being parallel to the diaphragm and support means width dimension and substantially perpendicular to the diaphragm and support means length dimension, for improved electro-acoustic conversion efficiency particularly in the low frequency range of the transducer.
Claim 2
Dependent Claim 173 words
A piezoelectric electro-acoustic transducer comprising: a piezoelectric diaphragm made of a high polymeric resin having its molecules uniaxially oriented, said diaphragm having a great anisotropy in the plane thereof and being of an elongate shape having a length dimension greater than its width dimension; a support means conforming in plan to said diaphragm such that its length correspondingly exceeds its width, such support means including a rigid perforate base plate behind said diaphragm, a resilient foam backing member sandwiched between the major central areas of said diaphragm and base plate in fixed relation to said base plate, and at least one opposed pair of elongate, stiff fixing members along opposed edges of said diaphragm for fixing said diaphragm edges with respect to said base plate; the resultant vector of the piezoelectric constants in the plane of said diaphragm being parallel to the diaphragm and support means width dimension and substantially perpendicular to the diaphragm and support means length dimension, for improved electro-acoustic conversion efficiency particularly in the low frequency range of the transducer.
Claim 3
Dependent Claim 42 words
A piezoelectric electro-acoustic transducer as claimed in claim 1, in which said diaphragm resin is polyvinylidene fluoride resin uniaxially stretched in the direction of molecular orientation, the direction of stretch being along the narrower, width dimension of said diaphragm and support means.
Claim 4
Dependent Claim 20 words
A piezoelectric electro-acoustic transducer as claimed in claim 2, in which said diaphragm and base plate are rectangular in shape.
Claim 5
Dependent Claim 20 words
A piezoelectric electro-acoustic transducer as claimed in claim 2, in which said diaphragm and base plate are oval in shape.
Claim 6
Dependent Claim 65 words
A piezoelectric electro-acoustic transducer as claimed in claim 2, in which said fixing members comprise a rectangular frame overlying the perimeter of each of the diaphragm and base plate, said resilient backing member having a perimeter spaced inboard of said frame, said resultant vector of piezoelectroc constants in the plane of said diaphragm extending substantially perpendicular to the length dimension of said fixing member frame.
Claim 7
Dependent Claim 83 words
In a piezoelectric electro-acoustic transducer comprising a piezoelectric diaphragm made of a high polymeric resin and having its molecules uniaxially oriented, said piezoelectric diaphragm having a great anisotropy in the plane thereof and being of a shape having a major axis and a minor axis; and a support means for fixing said piezoelectric diaphragm; the improvement wherein the direction of the resultant vector of the piezoelectric constants in the plane of the diaphragm is in parallel with said minor axis of said diaphragm.
Claim 8
Dependent Claim 83 words
In a piezoelectric electro-acoustic transducer comprising a piezoelectric diaphragm made of a high polymeric resin and having its molecules uniaxially oriented, said piezoelectric diaphragm having a great anisotropy in the plane thereof and being of a shape having a major axis and a minor axis; and a support means for fixing said piezoelectric diaphragm; the improvement wherein the direction of the resultant vector of the piezoelectric constants in the plane of the diaphragm is in parallel with said minor axis of said diaphragm.
Claim 9
Dependent Claim 32 words
A piezoelectric electro-acoustic transducer as claimed in claim 6, wherein said support means consists of at least a pair of fixing members made of stiff substance and located opposite to each other.
Claim 10
Dependent Claim 80 words
In a piezoelectric electro-acoustic transducer comprising a piezoelectric diaphragm made of a high polymeric resin and having its molecules uniaxially oriented, said piezoelectric diaphragm having a great anisotropy in the plane thereof and being of a shape having a major axis and a minor axis; and a support means for fixing said piezoelectric diaphragm; the improvement wherein the direction in which said piezoelectric diaphragm has the largest piezoelectric constant in its plane is in parallel with said minor axis thereof.
Claim 11
Dependent Claim 80 words
In a piezoelectric electro-acoustic transducer comprising a piezoelectric diaphragm made of a high polymeric resin and having its molecules uniaxially oriented, said piezoelectric diaphragm having a great anisotropy in the plane thereof and being of a shape having a major axis and a minor axis; and a support means for fixing said piezoelectric diaphragm; the improvement wherein the direction in which said piezoelectric diaphragm has the largest piezoelectric constant in its plane is in parallel with said minor axis thereof.

References Cited (Backward Citations)

US3832580A Cited
US3792204A Cited
US3894198A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1979-08-03 1980-02-02 1980-08-03 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1983-08-03 1984-02-02 1984-08-03 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1987-08-03 1988-02-02 1988-08-03 $7700.00 Window Closed / Lapsed

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