US2646144A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Drill apparatus with safety control
Assignee: CRICHTON Co
•
Filing: 1948-02-04
•
Granted: 1953-07-21
•
Expires: 1968-02-04
Abstract
No abstract record available.
Inventors
- 👤 Jr Andrew B Crichton
- 👤 Carl G Wennerstrom
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 00:26
CPC Classifications
E; E21; E21B; E21B3/00; E21B3/02; E21B3/035; Y; Y10; Y10T; Y10T408/00; Y10T408/65; Y10T408/675; Y10T408/6771; Y10T408/6774; Y10T74/00; Y10T74/19; Y10T74/19219; Y10T74/19242
Claims Analysis
Total Claims: 0
No claims parsed yet. Click Sync Now above to re-index claims from Google Patents.
References Cited (Backward Citations)
US1002310A
Cited
US1203751A
Cited
US1247829A
Cited
DE382973C
Cited
US1572067A
Cited
US1684231A
Cited
GB298026A
Cited
US1903963A
Cited
US2151338A
Cited
US2141209A
Cited
US2231465A
Cited
US2245471A
Cited
US2483613A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1956-07-20 | 1957-01-19 | 1957-07-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1960-07-20 | 1961-01-19 | 1961-07-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1964-07-20 | 1965-01-19 | 1965-07-21 | $7700.00 | Window Closed / Lapsed |