Patent US4213008A successfully refreshed from Google Patents.
US4213008A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Loudspeaker enclosure for mid-wall location
Assignee: Individual
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Filing: 1978-11-22
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Granted: 1980-07-15
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Expires: 1998-11-22
Abstract
Abstract A loudspeaker enclosure comprising a cabinet to be located adjacent to a wall and having a horn contained therein driven by two loudspeakers oriented at right angles to the axis of the throat portion of the horn in which they are located and on opposite sides thereof, the speakers being substantially aligned in close mutual proximity and driven out-of-phase to provide adequate drive to the horn while tending to damp each other's excursions, and the horn having an internal expansion air column which extends into an external expansion air column bounded by the cabinet and by the wall and floor of the room, the external air column having a catenoidal rate of expansion which terminates in very rapid flaring closely matching the high expansion rate of the air column into the room which results from placing the horn at a mid-wall location, as distinguished from a corner-wall location.
Inventors
- 👤 Edmund R. Helffrich
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 09:00
CPC Classifications
H; H04; H04R; H04R1/00; H04R1/20; H04R1/22; H04R1/30; H04R1/227
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
280 words
A loudspeaker enclosure system to be placed on the floor of a room in front of a wall at a mid-wall location and spaced outwardly therefrom, comprising: (a) a cabinet having a front panel, side panels, a rear panel, and a top and a bottom; (b) a horn in said cabinet having a first smaller air column expansion portion located near the front of the cabinet, the horn expanding down the cabinet from a throat portion located near the top thereof, and the first expansion portion joining a second larger expansion portion curving rearwardly of the cabinet and opening outwardly thereof at a mouth extending through the rear panel; (c) the first smaller portion of the horn lying against the front panel of the cabinet and having a rear horn wall located intermediate the front and rear cabinet panels; (d) the second larger air column expansion portion of the horn comprising a front horn wall curving from the front panel of the cabinet rearwardly across the bottom of the cabinet, and said rear horn wall curving downwardly, rearwardly and then upwardly in the cabinet to meet the cabinet rear panel at the mouth, the curvature of the front and rear horn walls providing an exponential expansion rate in the second larger portion of the horn; (e) driver loudspeaker means in the throat portion of the horn; and (f) the side panels and the rear panel of the cabinet being so proportioned that when the cabinet is placed at a mid-wall location, these panels form with the wall and floor of the room a third air column expansion portion beyond the mouth of the horn and having a catenoidal expansion rate.
Claim 2
Dependent Claim
280 words
A loudspeaker enclosure system to be placed on the floor of a room in front of a wall at a mid-wall location and spaced outwardly therefrom, comprising: (a) a cabinet having a front panel, side panels, a rear panel, and a top and a bottom; (b) a horn in said cabinet having a first smaller air column expansion portion located near the front of the cabinet, the horn expanding down the cabinet from a throat portion located near the top thereof, and the first expansion portion joining a second larger expansion portion curving rearwardly of the cabinet and opening outwardly thereof at a mouth extending through the rear panel; (c) the first smaller portion of the horn lying against the front panel of the cabinet and having a rear horn wall located intermediate the front and rear cabinet panels; (d) the second larger air column expansion portion of the horn comprising a front horn wall curving from the front panel of the cabinet rearwardly across the bottom of the cabinet, and said rear horn wall curving downwardly, rearwardly and then upwardly in the cabinet to meet the cabinet rear panel at the mouth, the curvature of the front and rear horn walls providing an exponential expansion rate in the second larger portion of the horn; (e) driver loudspeaker means in the throat portion of the horn; and (f) the side panels and the rear panel of the cabinet being so proportioned that when the cabinet is placed at a mid-wall location, these panels form with the wall and floor of the room a third air column expansion portion beyond the mouth of the horn and having a catenoidal expansion rate.
Claim 3
Dependent Claim
78 words
The loudspeaker enclosure system as claimed in claim 1, wherein said driver loudspeaker means comprises a first loudspeaker in the throat portion directed through the front panel to provide front radiation into the room and back radiation into the horn, and a second loudspeaker in the cabinet behind the throat portion and directed through the rear horn wall to provide front radiation into the horn, the loudspeakers being substantially axially aligned, and being electrically interconnected in out-of-phase relationship.
Claim 4
Dependent Claim
34 words
The loudspeaker enclosure system as claimed in claim 2, wherein the spacing between the front panel and the rear horn wall at the throat portion is just great enough to receive the first loudspeaker.
Claim 5
Dependent Claim
38 words
The loudspeaker enclosure system as claimed in claim 2, wherein the rear horn wall is canted out of parallel relationship with the front panel of the cabinet, thereby deflecting the axes of the loudspeakers out of perfect alignment.
Claim 6
Dependent Claim
69 words
The loudspeaker enclosure system as claimed in claim 4, wherein the first horn portion has a conical expansion rate, and wherein the first portion includes a diagonal wall extending downwardly in the cabinet between the throat and the second expansion portion, the diagonal wall and the throat portion being located with respect to the front panel so that a portion of the front panel is outside of the throat.
Claim 7
Dependent Claim
34 words
The loudspeaker enclosure system as claimed in claim 5, wherein said portion of the front panel which is outside of the throat has at least one additional loudspeaker directed therethrough for radiating higher frequencies.
Claim 8
Dependent Claim
149 words
A loudspeaker enclosure system including a cabinet having a front panel for facing into the listening area a room and having a horn within the cabinet, the horn having a front horn wall common with said front panel and having a rear wall spaced from the front wall, said horn walls defining a throat portion of the horn, and they sy having loudspeaker driver means at said throat portion and com a first loudspeaker mounted in the front horn wall and having cone facing into the room, a second loudspeaker mounted in the rear horn wall and having a cone facing toward the first loudspeaker, and the loudspeakers being interconnected for receiving electrical drive in such phase relationship that the cones of the loudspeakers move oppositely, whereby either to simultaneously compress or rarefy the air in the horn throat portion while the first loudspeaker radiates directly into the room.
Claim 9
Dependent Claim
149 words
A loudspeaker enclosure system including a cabinet having a front panel for facing into the listening area a room and having a horn within the cabinet, the horn having a front horn wall common with said front panel and having a rear wall spaced from the front wall, said horn walls defining a throat portion of the horn, and they sy having loudspeaker driver means at said throat portion and com a first loudspeaker mounted in the front horn wall and having cone facing into the room, a second loudspeaker mounted in the rear horn wall and having a cone facing toward the first loudspeaker, and the loudspeakers being interconnected for receiving electrical drive in such phase relationship that the cones of the loudspeakers move oppositely, whereby either to simultaneously compress or rarefy the air in the horn throat portion while the first loudspeaker radiates directly into the room.
Claim 10
Dependent Claim
47 words
A loudspeaker enclosure system as claimed in claim 7, wherein the loudspeakers are mounted opposite each other in said horn walls with their axes substantially aligned, but with their axes slightly canted with respect to one another, thereby to minimize standing waves in the air space therebetween.
Claim 11
Dependent Claim
81 words
A loudspeaker enclosure system as claimed in claim 7, wherein the front panel of the cabinet comprises the front horn wall, and the first loudspeaker is located inside the throat portion and mounted to radiate with front radiation through a hole in the front panel and with back radiation into the horn, and said second loudspeaker is located outside the throat portion and mounted to radiate with front radiation through a hole in the rear horn wall into the throat portion.
Claim 12
Dependent Claim
47 words
A loudspeaker enclosure system as claimed in claim 9, wherein the throat is only deep enough as measured between its front and back horn walls to receive the first loudspeaker, and wherein the cabinet is fully enclosed behind the rear horn wall and about the second loudspeaker.
References Cited (Backward Citations)
US2969848A
Cited
US3898384A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1983-07-15 | 1984-01-14 | 1984-07-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1987-07-15 | 1988-01-14 | 1988-07-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1991-07-15 | 1992-01-14 | 1992-07-15 | $7700.00 | Window Closed / Lapsed |