Patent US3144240A successfully refreshed from Google Patents.
US3144240A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Tractor for duct crawler
Assignee: Chicago Pneumatic Tool Co LLC
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Filing: 1962-07-16
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Granted: 1964-08-11
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Expires: 1982-07-16
Abstract
No abstract record available.
Inventors
- 👤 Edwin L Connell
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 01:22
CPC Classifications
B; B08; B08B; B08B9/00; B08B9/02; B08B9/027; B08B9/04; B08B9/049; F; F16; F16L; F16L2101/00; F16L2101/40
Claims Analysis
Total Claims: 1
Claim 1
Independent Claim
91 words
IN A SELF-PROPELLED DUCT CRAWLER, A TRACTOR COMPRISING A CORE, A PLURALITY OF PAIRS OF FLEXIBLE TINES EXTENDING OUTWARDLY AND REARWARDLY FROM SAID CORE, EACH PAIR OF TINES BEING OF APPROXIMATELY HAIRPIN SHAPE AND COMPRISING TWO ARMS CONNECTED BY A CURVED BIGHT PORTION, THE EXTREMITIES OF THE ARMS BEING ENGAGEABLE WITH THE INNER WALL OF THE DUCT, THE CORE HAVING AN ARCUATE GROOVE ASSOCIATED WITH EACH PAIR OF TINES, SAID GROOVE FITTING THE BIGHT PORTION OF THE PAIR OF TINES TO PROVIDE A SADDLE TO SUSTAIN INWARD THRUST ON THE TINES.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1967-08-11 | 1968-02-10 | 1968-08-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1971-08-11 | 1972-02-10 | 1972-08-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1975-08-11 | 1976-02-10 | 1976-08-11 | $7700.00 | Window Closed / Lapsed |