US3307876A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Tunnelling machine having cylindrical rotor and central conveyor
Assignee: Individual
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Filing: 1964-06-22
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Granted: 1967-03-07
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Expires: 1984-06-22
Abstract
No abstract record available.
Inventors
- 👤 Donald H Akkerman
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 20:56
CPC Classifications
E; E21; E21D; E21D9/00; E21D9/10; E21D9/11
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
125 words
IN AN EARTH BORING MACHINE: (A) A CYLINDRICAL OPEN ENDED CASING DISPOSED ON A GENERALLY HORIZONTAL AXIS, (B) AN OPEN ENDED CYLINDRICAL ROTOR OF SLIGHTLY LESS DIAMETER THAN SAID CASING DISPOSED CONCENTRICALLY WITHIN SAID CASING AND HAVING A FRONT END DISPOSED ADJACENT ONE END OF SAID CASING AND A REAR END AXIALLY INWARDLY SPACED A SHORT DISTANCE FROM THE OTHER END OF SAID CASING, (C) MEANS MOUNTING SAID ROTOR FOR ROTATION IN SAID CASING ON THE COMMON AXIS THEREOF, (D) A BORING BAR EXTENDING DIAMETRICALLY OF SAID ROTOR AND RELEASABLY ANCHORED AT ITS OPPOSITE ENDS TO THE FRONT END OF SAID ROTOR FOR COMMON ROTATION THEREWITH, (E) A PLURALITY OF BORING BITS ON SAID BORING BAR PROJECTING FORWARDLY OF THE ADJACENT END OF SAID CASING,
Claim 2
Dependent Claim
125 words
IN AN EARTH BORING MACHINE: (A) A CYLINDRICAL OPEN ENDED CASING DISPOSED ON A GENERALLY HORIZONTAL AXIS, (B) AN OPEN ENDED CYLINDRICAL ROTOR OF SLIGHTLY LESS DIAMETER THAN SAID CASING DISPOSED CONCENTRICALLY WITHIN SAID CASING AND HAVING A FRONT END DISPOSED ADJACENT ONE END OF SAID CASING AND A REAR END AXIALLY INWARDLY SPACED A SHORT DISTANCE FROM THE OTHER END OF SAID CASING, (C) MEANS MOUNTING SAID ROTOR FOR ROTATION IN SAID CASING ON THE COMMON AXIS THEREOF, (D) A BORING BAR EXTENDING DIAMETRICALLY OF SAID ROTOR AND RELEASABLY ANCHORED AT ITS OPPOSITE ENDS TO THE FRONT END OF SAID ROTOR FOR COMMON ROTATION THEREWITH, (E) A PLURALITY OF BORING BITS ON SAID BORING BAR PROJECTING FORWARDLY OF THE ADJACENT END OF SAID CASING,
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) | 1970-03-06 | 1970-09-05 | 1971-03-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1974-03-06 | 1974-09-05 | 1975-03-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1978-03-06 | 1978-09-05 | 1979-03-07 | $7700.00 | Window Closed / Lapsed |