US3136383A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Duplex loud speaker sound box system
Assignee: Individual
•
Filing: 1963-03-15
•
Granted: 1964-06-09
•
Expires: 1983-03-15
Abstract
No abstract record available.
Inventors
- 👤 Herbert J Hopkins
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 12:30
CPC Classifications
H; H04; H04R; H04R1/00; H04R1/20; H04R1/22; H04R1/227
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
110 words
IN A LOUD SPEAKER SOUND BOX OF THE TYPE HAVING FOUR ELONGATED SIDE WALLS DEFINING A HORIZONTAL, TUBULAR, MAIN SOUND CHAMBER WITH OPPOSITE OPEN ENDS AND HAVING A BAFFLE EXTENDING TRANSVERSELY OF SAID MAIN CHAMBER TO DIVIDE THE SAME INTO TWO OPPOSITE SUB CHAMBERS, SUBSTANTIALLY EQUAL IN VOLUME, THE COMBINATION OF A PAIR OF JUXTAPOSED, IDENTICAL LOUD SPEAKER OPENINGS IN SAID BAFFLE, AND A PAIR OF IDENTICAL, LOUD SPEAKERS OPPOSITELY DISPOSED ON SAID BAFFLE, EACH LOCATED IN ONE OF SAID OPPOSITE SUB CHAMBERS AND HAVING ITS MOUTH SPANNING ONE OF SAID OPENINGS TO RADIATE SOUND WAVES REARWARDLY INTO SAID ONE SUB CHAMBER AND FORWARDLY INTO THE OTHER SAID SUB CHAMBER.
Claim 2
Dependent Claim
110 words
IN A LOUD SPEAKER SOUND BOX OF THE TYPE HAVING FOUR ELONGATED SIDE WALLS DEFINING A HORIZONTAL, TUBULAR, MAIN SOUND CHAMBER WITH OPPOSITE OPEN ENDS AND HAVING A BAFFLE EXTENDING TRANSVERSELY OF SAID MAIN CHAMBER TO DIVIDE THE SAME INTO TWO OPPOSITE SUB CHAMBERS, SUBSTANTIALLY EQUAL IN VOLUME, THE COMBINATION OF A PAIR OF JUXTAPOSED, IDENTICAL LOUD SPEAKER OPENINGS IN SAID BAFFLE, AND A PAIR OF IDENTICAL, LOUD SPEAKERS OPPOSITELY DISPOSED ON SAID BAFFLE, EACH LOCATED IN ONE OF SAID OPPOSITE SUB CHAMBERS AND HAVING ITS MOUTH SPANNING ONE OF SAID OPENINGS TO RADIATE SOUND WAVES REARWARDLY INTO SAID ONE SUB CHAMBER AND FORWARDLY INTO THE OTHER SAID SUB CHAMBER.
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Cited
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Cited
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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) | 1967-06-09 | 1967-12-09 | 1968-06-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1971-06-09 | 1971-12-09 | 1972-06-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1975-06-09 | 1975-12-09 | 1976-06-09 | $7700.00 | Window Closed / Lapsed |