US2424422A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Hearing aid apparatus
Assignee: PARAPHONE HEARING AID Inc
•
Filing: 1943-06-12
•
Granted: 1947-07-22
•
Expires: 1963-06-12
Abstract
No abstract record available.
Inventors
- 👤 Raleigh E Tresise
- 👤 Paul D Kendall
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 02:48
CPC Classifications
H; H04; H04R; H04R25/00; H04R25/04; H04R25/60; H04R25/603; H04R25/604; H04R25/609
Claims Analysis
Total Claims: 0
No claims parsed yet. Click Sync Now above to re-index claims from Google Patents.
References Cited (Backward Citations)
US1805362A
Cited
US2017358A
Cited
US2192669A
Cited
US2148233A
Cited
US2182865A
Cited
US2308550A
Cited
US2327137A
Cited
US2327321A
Cited
US2327320A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1950-07-21 | 1951-01-20 | 1951-07-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1954-07-21 | 1955-01-20 | 1955-07-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1958-07-21 | 1959-01-20 | 1959-07-22 | $7700.00 | Window Closed / Lapsed |