Patent US3246576A successfully refreshed from Google Patents.
US3246576A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Mine roof supports
Assignee: Coal Industry Patents Ltd
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Filing: 1964-02-06
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Granted: 1966-04-19
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Expires: 1984-02-06
Abstract
No abstract record available.
Inventors
- 👤 Kibble John Dunbar
- 👤 Penn Ronald George
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 20:11
CPC Classifications
E; E21; E21D; E21D23/00; E21D23/16; E21D23/18; E21D23/20
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
220 words
A MINE ROOF SUPPORT SYSTEM COMPRISING A PLURALITY OF EXTENSIBLE AND RETRACTABLE PRESSURE FLUID OPERATED MINE ROOF SUPPORTS ADAPTED TO BE ADVANCED IN A PREDETERMINED SEQUENCE AND ARRANGED AT SPACED INTERVALS ALONG A LONGWALL MINERAL FACE, AND FURTHER COMPRISING CONTROL MEANS MOUNTED ON EACH SUPPORT FOR CONTROLLING THE CYCLE OF LOWERING, ADVANCING, AND RESETTING OPERATIONS OF THE SUPPORT, EACH SAID CONTROL MEANS INCLUDING INITIATING MEANS ADAPTED AUTOMATICALLY TO INITIATE THE SAID CYCLE AND CHECK MEANS HAVING A "CLEAR" CONDITION AND A "STOP" CONDITION AND ADAPTED TO BE AUTOMATICALLY PLACED IN THE CLEAR CONDITION WHEN THE SUPPORT HAS COMPLETED THE SAID CYCLE OF OPERATION, CONNECTION MEANS ARRANGED TO CONNECT THE CONTROL MEANS FOR ONE SUPPORT TO THE CONTROL MEANS FOR THE NEXT SUPPORT IN THE SEQUENCE TO BE ADVANCED, THE CHECK MEANS ON ONE SUPPORT, THE CONNECTION MEANS, AND THE INITIATING MEANS ON THE NEXT SUPPORT IN THE SEQUENCE TO BE ADVANCED BEING DIRECTLY CONNECTED IN SERIES SO THAT UPON THE SAID CHECK MEANS BEING PLACED IN A CLEAR CONDITION AN UNBROKEN ELECTRICAL SIGNAL PATH EXISTS BETWEEN THE CONTROL MEANS FOR SAID ONE SUPPORT AND THE INITIATING MEANS FOR SAID NEXT SUPPORT IN THE SEQUENCE TO BE ADVANCED, WHEREBY THE CYCLE OF OPERATIONS FOR SAID NEXT SUPPORT IS ONLY INITIATED UPON COMPLETION OF THE CYCLE OF OPERATIONS OF SAID ONE SUPPORT.
Claim 2
Dependent Claim
220 words
A MINE ROOF SUPPORT SYSTEM COMPRISING A PLURALITY OF EXTENSIBLE AND RETRACTABLE PRESSURE FLUID OPERATED MINE ROOF SUPPORTS ADAPTED TO BE ADVANCED IN A PREDETERMINED SEQUENCE AND ARRANGED AT SPACED INTERVALS ALONG A LONGWALL MINERAL FACE, AND FURTHER COMPRISING CONTROL MEANS MOUNTED ON EACH SUPPORT FOR CONTROLLING THE CYCLE OF LOWERING, ADVANCING, AND RESETTING OPERATIONS OF THE SUPPORT, EACH SAID CONTROL MEANS INCLUDING INITIATING MEANS ADAPTED AUTOMATICALLY TO INITIATE THE SAID CYCLE AND CHECK MEANS HAVING A "CLEAR" CONDITION AND A "STOP" CONDITION AND ADAPTED TO BE AUTOMATICALLY PLACED IN THE CLEAR CONDITION WHEN THE SUPPORT HAS COMPLETED THE SAID CYCLE OF OPERATION, CONNECTION MEANS ARRANGED TO CONNECT THE CONTROL MEANS FOR ONE SUPPORT TO THE CONTROL MEANS FOR THE NEXT SUPPORT IN THE SEQUENCE TO BE ADVANCED, THE CHECK MEANS ON ONE SUPPORT, THE CONNECTION MEANS, AND THE INITIATING MEANS ON THE NEXT SUPPORT IN THE SEQUENCE TO BE ADVANCED BEING DIRECTLY CONNECTED IN SERIES SO THAT UPON THE SAID CHECK MEANS BEING PLACED IN A CLEAR CONDITION AN UNBROKEN ELECTRICAL SIGNAL PATH EXISTS BETWEEN THE CONTROL MEANS FOR SAID ONE SUPPORT AND THE INITIATING MEANS FOR SAID NEXT SUPPORT IN THE SEQUENCE TO BE ADVANCED, WHEREBY THE CYCLE OF OPERATIONS FOR SAID NEXT SUPPORT IS ONLY INITIATED UPON COMPLETION OF THE CYCLE OF OPERATIONS OF SAID ONE SUPPORT.
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) | 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 |