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US4252211A Expired / Lapsed US ⏱️ 0.0 years remaining

Loudspeaker

Assignee: Sony Corp
•
Filing: 1979-08-10
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Granted: 1981-02-24
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Expires: 1999-08-10
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Abstract

Abstract A loudspeaker includes a flat plate diaphragm mounted in a speaker frame and which is driven by a plurality of magnetic drivers each having a magnetic gap, a voice coil bobbin connected to the diaphragm at a respective node portion of the divided vibration mode and a voice coil in the respective magnetic gap and being wound around the voice coil bobbin therein. Rotational vibration of the diaphragm is prevented by a pole member which is connected from the center of the diaphragm to a damper supported behind the speaker frame on a damper supporting frame. The leverage due to the longer length of the pole member makes the damper member more effective in resisting rotational vibration. The damper supporting frame is mechanically connected to the speaker frame and/or magnetic drivers to add stiffness to the structure.

Inventors

  • 👤 Atsushi Matsuda
  • 👤 Jun Kishigami

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-04 18:21
CPC Classifications
H; H04; H04R; H04R7/00; H04R7/02; H04R7/04; H04R1/00; H04R1/20; H04R1/22; H04R7/26; H04R9/00; H04R9/02; H04R9/06; H04R9/063; H04R9/025

Claims Analysis

Total Claims: 18
Claim 1
Independent Claim 67 words
A flat-plate loudspeaker comprising: a frame; a diaphragm; means for resiliently mounting said diaphragm in said frame; drive means mounted on said frame for driving said diaphragm at a plurality of points thereon; a pole connected to said diaphragm; means for damping movement of said pole; and supporting means connected to at least one of said frame and said drive means for supporting said means for damping.
Claim 2
Dependent Claim 67 words
A flat-plate loudspeaker comprising: a frame; a diaphragm; means for resiliently mounting said diaphragm in said frame; drive means mounted on said frame for driving said diaphragm at a plurality of points thereon; a pole connected to said diaphragm; means for damping movement of said pole; and supporting means connected to at least one of said frame and said drive means for supporting said means for damping.
Claim 3
Dependent Claim 22 words
A loudspeaker according to claim 1, wherein said points are disposed substantially at node portions of divided vibration modes of said diaphragm.
Claim 4
Dependent Claim 13 words
A loudspeaker according to claim 1, wherein said pole includes a cylindrical tube.
Claim 5
Dependent Claim 18 words
A loudspeaker according to claim 3, wherein said pole further includes sound absorbing means inside said cylindrical tube.
Claim 6
Dependent Claim 24 words
A loudspeaker according to claim 1, wherein said means for damping is connected between a free end of said pole and said supporting means.
Claim 7
Dependent Claim 32 words
A loudspeaker according to claim 5, wherein said means for damping includes a corrugated damper having an inside edge connected to said pole and an outside edge connected to said supporting means.
Claim 8
Dependent Claim 37 words
A loudspeaker according to claim 5, wherein said means for damping includes first and second magnetic members, said first magnetic member being connected to said pole and said second magnetic member being connected to said supporting means.
Claim 9
Dependent Claim 48 words
A loudspeaker according to claim 1, wherein said supporting means includes a support portion and at least one attaching portion, said support portion supporting said means for damping and said at least one attaching portion being connected to at least one of said drive means and said frame.
Claim 10
Dependent Claim 16 words
A Loudspeaker according to claim 8, wherein said supporting means is integrally formed with said frame.
Claim 11
Dependent Claim 13 words
A loudspeaker according to claim 8, wherein said support portion includes a ring.
Claim 12
Dependent Claim 14 words
A loudspeaker according to claim 8, wherein said support portion includes a crossbar-shaped portion.
Claim 13
Dependent Claim 23 words
A loudspeaker according to claim 8, wherein said at least one attaching portion includes a plurality of arm members connected to said frame.
Claim 14
Dependent Claim 28 words
A loudspeaker according to claim 8, wherein said at least one attaching portion includes arm members extended outward from said support portion and connected to said drive means.
Claim 15
Dependent Claim 32 words
A loudspeaker according to claim 8, wherein said at least one attaching portion includes a frame structure having a plurality of corners, said plurality of corners being connected to said drive means.
Claim 16
Dependent Claim 17 words
A loudspeaker according to claim 1, wherein said pole is connected to a center of said diaphragm.
Claim 17
Dependent Claim 72 words
A loudspeaker according to claim 1, wherein said drive means includes a plurality of magnetic drivers, each of said magnetic drivers having a magnetic gap, a voice coil bobbin and a voice coil in said magnetic gap wound around said voice coil bobbin, each said voice coil bobbin being connected to a respective one of said plurality of points on said diaphragm, and said pole being longer than said voice coil bobbin.
Claim 18
Dependent Claim 20 words
A loudspeaker according to claim 1; wherein said plurality of points surround a connection between said pole and said diaphragm.

References Cited (Backward Citations)

US2956538A Cited
US3767005A Cited
US3935400A Cited
US4122314A Cited
US4191863A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1984-02-24 1984-08-25 1985-02-24 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1988-02-24 1988-08-25 1989-02-24 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1992-02-24 1992-08-25 1993-02-24 $7700.00 Window Closed / Lapsed

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