US3129298A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electro-dynamic conical loudspeaker
Assignee: US Philips Corp
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Filing: 1961-05-08
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Granted: 1964-04-14
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Expires: 1981-05-08
Abstract
No abstract record available.
Inventors
- 👤 Hofman Wytze
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 08:38
CPC Classifications
H; H04; H04R; H04R9/00; H04R9/02
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
99 words
A LOUDSPEAKER COMPRISING AN AXIALLY POLARIZED PERMANENT MAGNET OF ANNULAR CONFIGURATION, A SOFT IRON DISC SHAPED FOOT PLATE SUPPORTING SAID MAGNET, A MAGNETIZABLE CORE ON SAID FOOT PLATE CONCENTRIC WITH SAID MAGNET, A CONICAL SOFT IRON LID PLATE SUPPORTED ON SAID MAGNET, SAID LID PLATE HAVING A CENTRAL CONCAVITY EXTENDING TOWARD SAID FOOT PLATE AND SPACED THEREFROM, A CENTRAL APERTURE IN SAID LID PLATE DEFINING AN AIR GAP WITH SAID CORE A VOICE COIL WITHIN SAID AIR GAP, A SPEAKER DIAPHRAGM SUPPORTING SAID VOICE COIL, SAID DIAPHRAGM SECURED TO SAID LID PLATE AND RECEIVABLE WITHIN SAID CENTRAL CONCAVITY, A
Claim 2
Dependent Claim
99 words
A LOUDSPEAKER COMPRISING AN AXIALLY POLARIZED PERMANENT MAGNET OF ANNULAR CONFIGURATION, A SOFT IRON DISC SHAPED FOOT PLATE SUPPORTING SAID MAGNET, A MAGNETIZABLE CORE ON SAID FOOT PLATE CONCENTRIC WITH SAID MAGNET, A CONICAL SOFT IRON LID PLATE SUPPORTED ON SAID MAGNET, SAID LID PLATE HAVING A CENTRAL CONCAVITY EXTENDING TOWARD SAID FOOT PLATE AND SPACED THEREFROM, A CENTRAL APERTURE IN SAID LID PLATE DEFINING AN AIR GAP WITH SAID CORE A VOICE COIL WITHIN SAID AIR GAP, A SPEAKER DIAPHRAGM SUPPORTING SAID VOICE COIL, SAID DIAPHRAGM SECURED TO SAID LID PLATE AND RECEIVABLE WITHIN SAID CENTRAL CONCAVITY, A
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1967-04-14 | 1967-10-14 | 1968-04-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1971-04-14 | 1971-10-14 | 1972-04-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1975-04-14 | 1975-10-14 | 1976-04-14 | $7700.00 | Window Closed / Lapsed |