Patent US3217606A successfully refreshed from Google Patents.
US3217606A
Expired / Lapsed
US
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Advanceable roof support assemblies
Assignee: Dowty Mining Equipment Ltd
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Filing: 1964-09-01
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Granted: 1965-11-16
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Expires: 1984-09-01
Abstract
No abstract record available.
Inventors
- 👤 Bolton Douglas Herbert Hewlett
- 👤 Pawling Frank
- 👤 Potts Michael Charles
- 👤 Cannon Dennis Henry
- 👤 Winder Richard Henry Bryan
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 12:53
CPC Classifications
E; E21; E21D; E21D23/00; E21D23/16
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
175 words
AN ADVANCEABLE ROOF SUPPORT ASSEMBLY INCLUDING A SERIES OF ADVANCEABLE FLUID-PRESSURE-OPERATED ROOF SUPPORTS, EACH ROOF SUPPORT INCLUDING A FIRST VALVE ASSEMBLY OPERABLE TO CAUSE THE ROOF SUPPORT TO UNDERGO AN ADVANCING OPERATION, AN ADVANCE-START LINE CONNECTED TO THE FIRST VALVE ASSEMBLY TO INITIATE OPERATION OF THE FIRST VALVE ASSEMBLY UPON PRESSURISATION OF THE ADVANCE-START LINE, AND A SECOND VALVE ASSEMBLY CONNECTED TO THE ADVANCESTART LINE OF THAT ROOF SUPPORT, A SIGNAL LINE CONNECTED FROM THE SECOND VALVE ASSEMBLY OF EACH ROOF SUPPORT TO THE SECOND VALVE ASSEMBLY OF THE NEXT ROOF SUPPORT, AND MEANS FOR OPERATING EACH SECOND VALVE ASSEMBLY TO PRESSURISE ALTERNATIVELY THE SINGLE LINE CONNECTED TO THE PRECEDING ROOF SUPPORT OR THE SIGNAL LINE CONNECTED TO THE NEXT ROOF SUPPORT WITH CONSEQUENT PRESSURISATION OF THE ADVANCE-START LINE AND ADVANCE OF THE PRECEDING ROOF SUPPORT OR THE NEXT ROOF SUPPORT RESPECTIVELY, AND EACH SECOND VALVE ASSEMBLY INCLUDING MEANS TO PREVENT PRESSURISATION OF THE ADVANCE-START LINE OF THE ROOF SUPPORT IN WHICH THE SECOND VALVE ASSEMBLY IS INCLUDED WHEN SAID SECOND VALVE ASSEMBLY IS OPERATED.
Claim 2
Dependent Claim
175 words
AN ADVANCEABLE ROOF SUPPORT ASSEMBLY INCLUDING A SERIES OF ADVANCEABLE FLUID-PRESSURE-OPERATED ROOF SUPPORTS, EACH ROOF SUPPORT INCLUDING A FIRST VALVE ASSEMBLY OPERABLE TO CAUSE THE ROOF SUPPORT TO UNDERGO AN ADVANCING OPERATION, AN ADVANCE-START LINE CONNECTED TO THE FIRST VALVE ASSEMBLY TO INITIATE OPERATION OF THE FIRST VALVE ASSEMBLY UPON PRESSURISATION OF THE ADVANCE-START LINE, AND A SECOND VALVE ASSEMBLY CONNECTED TO THE ADVANCESTART LINE OF THAT ROOF SUPPORT, A SIGNAL LINE CONNECTED FROM THE SECOND VALVE ASSEMBLY OF EACH ROOF SUPPORT TO THE SECOND VALVE ASSEMBLY OF THE NEXT ROOF SUPPORT, AND MEANS FOR OPERATING EACH SECOND VALVE ASSEMBLY TO PRESSURISE ALTERNATIVELY THE SINGLE LINE CONNECTED TO THE PRECEDING ROOF SUPPORT OR THE SIGNAL LINE CONNECTED TO THE NEXT ROOF SUPPORT WITH CONSEQUENT PRESSURISATION OF THE ADVANCE-START LINE AND ADVANCE OF THE PRECEDING ROOF SUPPORT OR THE NEXT ROOF SUPPORT RESPECTIVELY, AND EACH SECOND VALVE ASSEMBLY INCLUDING MEANS TO PREVENT PRESSURISATION OF THE ADVANCE-START LINE OF THE ROOF SUPPORT IN WHICH THE SECOND VALVE ASSEMBLY IS INCLUDED WHEN SAID SECOND VALVE ASSEMBLY IS OPERATED.
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) | 1968-11-15 | 1969-05-17 | 1969-11-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1972-11-15 | 1973-05-17 | 1973-11-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1976-11-15 | 1977-05-17 | 1977-11-16 | $7700.00 | Window Closed / Lapsed |