US3207041A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Hydraulically operated advancing roof support systems and monitoring systems therefor
Assignee: Electro Hydraulics Ltd
•
Filing: 1962-06-08
•
Granted: 1965-09-21
•
Expires: 1982-06-08
Abstract
No abstract record available.
Inventors
- 👤 Phillips John
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 03:36
CPC Classifications
E; E21; E21D; E21D23/00; E21D23/16; E21D23/18; E21D23/12; E21D23/14
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
197 words
AUTOMATICALLY OPERATING MEANS FOR HYDRAULICALLY OPERATED, SELF ADVANCING MINE ROOF SUPPORTING SYSTEMS WHICH INCLUDED A PLURALITY OF SUPPORT UNITS AN ADVANCING RAM FOR EACH SUPPORT UNIT, SAID AUTOMATICALLY OPERATING MEANS COMPRISING A PLURALITY OF HYDRAULIC VALVE MEANS FOR CONTROLLING THE SUPPLY OF HYDRAULIC PRESSURE TO EACH SUPPORT UNIT AND THE ADVANCING RAM THEREOF, SOLENOID CONTROL MEANS FOR SAID HYDRAULIC VALVE MEANS, TWO UNI-SELECTORS ARRANGED SEQUENTIALLY TO INITIATE SELECTION FOR OPERATION OF THE SAID HYDRAULIC VALVE MEANS OF EACH SUPPORT UNIT, FIRST ELECTRICAL SWITCH MEANS IN NUMBER CORRESPONDING TO THE NUMBER OF SAID SUPPORT UNITS AND ELECTRICALLY CONNECTED IN CIRUCIT WITH SAID SOLENOID CONTROL MEANS, EACH SAID FIRST ELECTRICAL SWITCH MEANS BEING OPERATED BY ITS CORRESPONDING RAM, AFTER HYDRAULIC PRESSURE HAS FULLY EXTENDED SAID RAM, TO EXHAUST SAID RAM TO CONDITION IT FOR SUBSEQUENT RETRACTION TO ADVANCE ITS SUPPORT UNIT, A SIMILAR NUMBER OF SECOND ELECTRICAL SWITCH MEANS, ONE FOR EACH OF SAID SUPPORT UNITS, OPERABLE TO PERMIT RELEASE OF ITS SUPPORT UNIT TO ENABLE IT TO ADVANCE, AND A SIMILAR NUMBER OF THIRD SWITCH MEANS, ONE FOR EACH OF SAID SUPPORT UNITS, OPERABLE TO ACTUATE SAID UNI-SELECTORS TO SELECT THE NEXT SUPPORT UNIT IN SEQUENCE FOR OPERATION.
Claim 2
Dependent Claim
197 words
AUTOMATICALLY OPERATING MEANS FOR HYDRAULICALLY OPERATED, SELF ADVANCING MINE ROOF SUPPORTING SYSTEMS WHICH INCLUDED A PLURALITY OF SUPPORT UNITS AN ADVANCING RAM FOR EACH SUPPORT UNIT, SAID AUTOMATICALLY OPERATING MEANS COMPRISING A PLURALITY OF HYDRAULIC VALVE MEANS FOR CONTROLLING THE SUPPLY OF HYDRAULIC PRESSURE TO EACH SUPPORT UNIT AND THE ADVANCING RAM THEREOF, SOLENOID CONTROL MEANS FOR SAID HYDRAULIC VALVE MEANS, TWO UNI-SELECTORS ARRANGED SEQUENTIALLY TO INITIATE SELECTION FOR OPERATION OF THE SAID HYDRAULIC VALVE MEANS OF EACH SUPPORT UNIT, FIRST ELECTRICAL SWITCH MEANS IN NUMBER CORRESPONDING TO THE NUMBER OF SAID SUPPORT UNITS AND ELECTRICALLY CONNECTED IN CIRUCIT WITH SAID SOLENOID CONTROL MEANS, EACH SAID FIRST ELECTRICAL SWITCH MEANS BEING OPERATED BY ITS CORRESPONDING RAM, AFTER HYDRAULIC PRESSURE HAS FULLY EXTENDED SAID RAM, TO EXHAUST SAID RAM TO CONDITION IT FOR SUBSEQUENT RETRACTION TO ADVANCE ITS SUPPORT UNIT, A SIMILAR NUMBER OF SECOND ELECTRICAL SWITCH MEANS, ONE FOR EACH OF SAID SUPPORT UNITS, OPERABLE TO PERMIT RELEASE OF ITS SUPPORT UNIT TO ENABLE IT TO ADVANCE, AND A SIMILAR NUMBER OF THIRD SWITCH MEANS, ONE FOR EACH OF SAID SUPPORT UNITS, OPERABLE TO ACTUATE SAID UNI-SELECTORS TO SELECT THE NEXT SUPPORT UNIT IN SEQUENCE FOR OPERATION.
References Cited (Backward Citations)
US2799811A
Cited
GB856719A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1968-09-20 | 1969-03-22 | 1969-09-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1972-09-20 | 1973-03-22 | 1973-09-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1976-09-20 | 1977-03-22 | 1977-09-21 | $7700.00 | Window Closed / Lapsed |