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US4190746A Expired / Lapsed US ⏱️ 0.0 years remaining

Diaphragm material for moving coil loudspeaker, may be laminated or integral with surround

Assignee: CHING PAO JOSEPH YEE MEI LAN COOMBE PARK KINGSTON UPON THAMES SURREY ENGLAND
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Filing: 1977-03-18
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Granted: 1980-02-26
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Expires: 1997-03-18
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Abstract

Abstract A diaphragm for a moving evil loudspeaker is formed of a material which has a mechanical "0"value of from 7 to 12, a Youngs modulus of from 8.5 to 17.5 x 105 KN/M2 and a density of from 0.85 to 1.05 g/cc. The diaphragm forming material is preferably formed of polypropylene or a propylene-containing copolymer. The diaphragm may be of cone or dome type and included are moving coil loudspeaker constructions wherein other vibrating elements, particularly spiders and outer cone support rings, are formed of the same type of material as the diaphragm.

Inventors

  • 👤 Hugh D. Harwood
  • 👤 Joseph Y. C. Pao
  • 👤 David W. Stebbings

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-24 07:18
CPC Classifications
H; H04; H04R; H04R7/00; H04R7/02; H04R7/12; H04R7/16; H04R2307/00; H04R2307/029

Claims Analysis

Total Claims: 12
Claim 1
Independent Claim 114 words
A diaphragm for a moving coil loudspeaker, the diaphragm being of conic section, of exponential section or having a cross-section over the major part thereof which is of conic section or of exponential section form, which diaphragm, in order to impart internal damping characteristics thereto, is formed of, or includes a layer of, a diaphragm-forming material selected from the group consisting of polypropylene, polyethylene and ethylene-propylene copolymers, the ethylene being present in copolymerized form in minor amount with respect to the propylene, said material having a mechanical "Q" value of from 7 to 12, a Young's modulus of from 8.5 to 17.5×10 5 KN/M 2 and a density of from 0.85 to 1.05 g/cc.
Claim 2
Dependent Claim 114 words
A diaphragm for a moving coil loudspeaker, the diaphragm being of conic section, of exponential section or having a cross-section over the major part thereof which is of conic section or of exponential section form, which diaphragm, in order to impart internal damping characteristics thereto, is formed of, or includes a layer of, a diaphragm-forming material selected from the group consisting of polypropylene, polyethylene and ethylene-propylene copolymers, the ethylene being present in copolymerized form in minor amount with respect to the propylene, said material having a mechanical "Q" value of from 7 to 12, a Young's modulus of from 8.5 to 17.5×10 5 KN/M 2 and a density of from 0.85 to 1.05 g/cc.
Claim 3
Dependent Claim 34 words
A diaphragm as claimed in claim 1, which has a sandwich structure, the diaphragm-forming material being covered on both sides with a material selected from the group consisting of plastics, metal and ceramic material.
Claim 4
Dependent Claim 24 words
A diaphragm as claimed in claim 2, wherein the plastics material is selected from the group consisting of polystyrene, polyvinylchloride, acrylonitrile-butadiene-styrene terpolymer and polyethylene.
Claim 5
Dependent Claim 22 words
A diaphragm as claimed in claim 2, wherein the metal material is selected from the group consisting of titanium, aluminum and beryllium.
Claim 6
Dependent Claim 123 words
A diaphragm for a moving coil loudspeaker, the diaphragm being of conic section, of exponential section or having a cross-section over the major part thereof which is of conic section or of exponential section form, which diaphragm incorporates, in order to impart internal damping characteristics thereto, a layer of a material selected from the group consisting of polypropylene, polyethylene and ethylene-propylene copolymers, and a coating of another plastics material thereon, the ethylene being present in said copolymer in copolymerized form in minor amount with respect to the propylene, the material of said layer having a mechanical "Q" value of from 7 to 12, a Young's modulus of from 8.5 to 17.5×10 5 KN/M 2 and a density of from 0.85 to 1.05 g/cc.
Claim 7
Dependent Claim 123 words
A diaphragm for a moving coil loudspeaker, the diaphragm being of conic section, of exponential section or having a cross-section over the major part thereof which is of conic section or of exponential section form, which diaphragm incorporates, in order to impart internal damping characteristics thereto, a layer of a material selected from the group consisting of polypropylene, polyethylene and ethylene-propylene copolymers, and a coating of another plastics material thereon, the ethylene being present in said copolymer in copolymerized form in minor amount with respect to the propylene, the material of said layer having a mechanical "Q" value of from 7 to 12, a Young's modulus of from 8.5 to 17.5×10 5 KN/M 2 and a density of from 0.85 to 1.05 g/cc.
Claim 8
Dependent Claim 27 words
A diaphragm as claimed in claim 5, wherein the plastics material is selected from the group consisting of low density polyethylene, medium density polyethylene and atactic polypropylene.
Claim 9
Dependent Claim 113 words
A moving-coil-type loudspeaker which comprises a diaphragm, the diaphragm being of conic section, of exponential section or having a cross-section over the major part thereof which is of conic section or of exponential section form, which diaphragm, in order to impart internal damping characteristics thereto, is formed of, or includes a layer of, a diaphragm-forming material selected from the group consisting of polypropylene, polyethylene and ethylene-propylene copolymers, the ethylene being present in copolymerized form in minor amount with respect to the propylene, said material having a mechanical "Q" value of from 7 to 12, a Young's modulus of from 8.5 to 17.5×10 5 KN/M 2 and a density from 0.85 to 1.05 g/cc.
Claim 10
Dependent Claim 113 words
A moving-coil-type loudspeaker which comprises a diaphragm, the diaphragm being of conic section, of exponential section or having a cross-section over the major part thereof which is of conic section or of exponential section form, which diaphragm, in order to impart internal damping characteristics thereto, is formed of, or includes a layer of, a diaphragm-forming material selected from the group consisting of polypropylene, polyethylene and ethylene-propylene copolymers, the ethylene being present in copolymerized form in minor amount with respect to the propylene, said material having a mechanical "Q" value of from 7 to 12, a Young's modulus of from 8.5 to 17.5×10 5 KN/M 2 and a density from 0.85 to 1.05 g/cc.
Claim 11
Dependent Claim 101 words
A loudspeaker as claimed in claim 7, which has said cone-type diaphragm mounted in a supporting basket to which said diaphragm is connected by means of an outer cone support ring which is formed of a plastic material, the plastics material being selected from the group consisting of polypropylene, polyethylene and ethylene-propylene copolymers, the ethylene being present in copolymerized form in minor amount with respect to the propylene, the plastics material having a mechanical "Q" value of from 7 to 12, a Young's modulus of from 8.5 to 17.5×10 5 KN/M 2 and a density of from 0.85 to 1.05 g/cc.
Claim 12
Dependent Claim 81 words
A loudspeaker as claimed in claim 7, which comprises at least one spider formed of a plastics material, the plastics material being selected from the group consisting of polypropylene, polyethylene and ethylene-propylene copolymers, the ethylene being present in copolymerized form in minor amount with respect to the propylene, said plastics material having a mechanical "Q" value of from 7 to 12, a Young's modulus of from 8.5 to 17.5×10 5 KN/M 2 and a density of from 0.85 to 1.05 g/cc.

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USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1983-02-25 1983-08-27 1984-02-26 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1987-02-25 1987-08-27 1988-02-26 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1991-02-25 1991-08-27 1992-02-26 $7700.00 Window Closed / Lapsed

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