US3246730A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Mining apparatus comprising automatically advancing jacks
Assignee: Dowty Mining Equipment Ltd
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Filing: 1964-06-09
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Granted: 1966-04-19
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Expires: 1984-06-09
Abstract
No abstract record available.
Inventors
- 👤 Bolton Douglas Herbert Hewlett
- 👤 Potts Michael Charles
- 👤 Pawling Frank
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 21:08
CPC Classifications
E; E21; E21D; E21D23/00; E21D23/006; E21D23/0065; F; F15; F15B; F15B9/00; F15B9/02; F15B9/08; F15B9/09
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
78 words
MINING APPARATUS INCLUDING A GUIDE MEANS EXTENDING ALONG THE WORKING FACE OF A MINE FOR GUIDING A CUTTING MACHINE ALONG THE WORKING FACE, A SERIES OF FLUID-PRESSUREOPERATED JACKS EACH OPERABLE TO APPLY AN ADVANCING FORCE TO THE GUIDE MEANS, AND ADJUSTABLE MEANS RESPONSIVE TO THE ADVANCE OF A PORTION OF THE GUIDE MEANS TO STOP THE ADVANCE OF THAT PORTION OF THE GUIDE MEANS, AFTER AN ADJUSTABLE PREDETERMINED ADVANCE THEREOF, BY RENDERING THE APPROPRIATE JACK OR JACKS INOPERATIVE.
Claim 2
Dependent Claim
78 words
MINING APPARATUS INCLUDING A GUIDE MEANS EXTENDING ALONG THE WORKING FACE OF A MINE FOR GUIDING A CUTTING MACHINE ALONG THE WORKING FACE, A SERIES OF FLUID-PRESSUREOPERATED JACKS EACH OPERABLE TO APPLY AN ADVANCING FORCE TO THE GUIDE MEANS, AND ADJUSTABLE MEANS RESPONSIVE TO THE ADVANCE OF A PORTION OF THE GUIDE MEANS TO STOP THE ADVANCE OF THAT PORTION OF THE GUIDE MEANS, AFTER AN ADJUSTABLE PREDETERMINED ADVANCE THEREOF, BY RENDERING THE APPROPRIATE JACK OR JACKS INOPERATIVE.
References Cited (Backward Citations)
GB816702A
Cited
US3120105A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1969-04-18 | 1969-10-18 | 1970-04-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1973-04-18 | 1973-10-18 | 1974-04-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1977-04-18 | 1977-10-18 | 1978-04-19 | $7700.00 | Window Closed / Lapsed |