US2831060A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of reproducing speech and music by means of loudspeakers
Assignee: US Philips Corp
•
Filing: 1955-10-11
•
Granted: 1958-04-15
•
Expires: 1975-10-11
Abstract
No abstract record available.
Inventors
- 👤 Kleis Derk
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 15:13
CPC Classifications
H; H04; H04S; H04S5/00
Claims Analysis
Total Claims: 0
No claims parsed yet. Click Sync Now above to re-index claims from Google Patents.
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) | 1961-04-14 | 1961-10-14 | 1962-04-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1965-04-14 | 1965-10-14 | 1966-04-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1969-04-14 | 1969-10-14 | 1970-04-15 | $7700.00 | Window Closed / Lapsed |