US2720136A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Projector
Assignee: W K KELLOGG FOUNDATION
•
Filing: 1952-02-18
•
Granted: 1955-10-11
•
Expires: 1972-02-18
Abstract
No abstract record available.
Inventors
- 👤 Wallace E Frank
- 👤 Herman P Schick
- 👤 Jr George J Kreier
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 10:04
CPC Classifications
G; G03; G03B; G03B21/00; G03B21/10
Claims Analysis
Total Claims: 0
No claims parsed yet. Click Sync Now above to re-index claims from Google Patents.
References Cited (Backward Citations)
DE453142C
Cited
US1218749A
Cited
US1831766A
Cited
US2047002A
Cited
US2064368A
Cited
US2260551A
Cited
US2389503A
Cited
US2558982A
Cited
US2505505A
Cited
US2468291A
Cited
US2579961A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1958-10-10 | 1959-04-11 | 1959-10-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1962-10-10 | 1963-04-11 | 1963-10-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1966-10-10 | 1967-04-11 | 1967-10-11 | $7700.00 | Window Closed / Lapsed |