US2741179A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electric detonators and electric blasting assemblies
Assignee: Imperial Chemical Industries Ltd
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Filing: 1951-02-06
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Granted: 1956-04-10
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Expires: 1971-02-06
Abstract
No abstract record available.
Inventors
- 👤 Taylor Wilfrid
- 👤 Forsyth William
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 03:50
CPC Classifications
F; F42; F42B; F42B3/00; F42B3/10; F42B3/18
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
147 words
AN IMPROVED BLASTING ASSEMBLY COMPRISING A PLURALITY OF ELECTRIC DETONATORS, THERE BEING IN EACH OF SAID DETONATORS INSULATED LEADING WIRES, A METAL CASING CONNECTED BY AN ELECTRIC CONDUCTOR TO ONE POLE PIECE OF A MATCH-HEAD FIRING CIRCUIT WHEREBY STRAY STATIC ELECTRICAL CHARGES ARE CAUSED TO PASS HARMLESSLY TO THE SAID METAL CASING, A SHEATH OF INSULATING MATERIAL COMPLETLY SURROUNDING SAID CASING, SAID SHEATH CAUSING THE SAID STATIC ELECTRICAL CHARGES TO BE RETAINED ON SAID METAL CASING SO THAT THE WHOLE DETONATOR SYSTEM IS AT THE SAME POTENTIAL UNTIL THE SAID STATIC ELECTRICAL CHARGES ARE GREATER THAN THE BREAKDOWN POTENTIAL OF THE SAID SHEATH IN WHICH CASE BREAKDOWN OCCURS AND THE SAID CHARGES ARE DISCHARGED TO EARTH, AND WHEREIN EACH OF SAID ELECTRIC DETONATORS IS CONNECTED IN SERIES WITH A SOURCE OF ELECTRIC CURRENT WHEREIN THE CABLES AND LEADING WIRES OUTSIDE THE DETONATORS ARE INSULATED FROM THE EARTH.
Claim 2
Dependent Claim
147 words
AN IMPROVED BLASTING ASSEMBLY COMPRISING A PLURALITY OF ELECTRIC DETONATORS, THERE BEING IN EACH OF SAID DETONATORS INSULATED LEADING WIRES, A METAL CASING CONNECTED BY AN ELECTRIC CONDUCTOR TO ONE POLE PIECE OF A MATCH-HEAD FIRING CIRCUIT WHEREBY STRAY STATIC ELECTRICAL CHARGES ARE CAUSED TO PASS HARMLESSLY TO THE SAID METAL CASING, A SHEATH OF INSULATING MATERIAL COMPLETLY SURROUNDING SAID CASING, SAID SHEATH CAUSING THE SAID STATIC ELECTRICAL CHARGES TO BE RETAINED ON SAID METAL CASING SO THAT THE WHOLE DETONATOR SYSTEM IS AT THE SAME POTENTIAL UNTIL THE SAID STATIC ELECTRICAL CHARGES ARE GREATER THAN THE BREAKDOWN POTENTIAL OF THE SAID SHEATH IN WHICH CASE BREAKDOWN OCCURS AND THE SAID CHARGES ARE DISCHARGED TO EARTH, AND WHEREIN EACH OF SAID ELECTRIC DETONATORS IS CONNECTED IN SERIES WITH A SOURCE OF ELECTRIC CURRENT WHEREIN THE CABLES AND LEADING WIRES OUTSIDE THE DETONATORS ARE INSULATED FROM THE EARTH.
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) | 1959-04-10 | 1959-10-10 | 1960-04-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1963-04-10 | 1963-10-10 | 1964-04-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1967-04-10 | 1967-10-10 | 1968-04-10 | $7700.00 | Window Closed / Lapsed |