Patent US3744416A successfully refreshed from Google Patents.
US3744416A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electronic safety bridge primer
Assignee: Dynamit Nobel AG
•
Filing: 1970-01-29
•
Granted: 1973-07-10
•
Expires: 1990-01-29
Abstract
Abstract A detonator element of the bridge-type adapted for electrical ignition having two electrodes supported in mutually spaced relationship by an electrically non-conductive support member, a bridging conductor connected across the ends of the electrodes and capable of incandescence or explosive evaporation, and an ignitible charge in contact with the bridging conductor, and further including a mechanically solid semiconductor exhibiting a resistance which is variable depending upon the voltage applied thereto, the semi-conductor being disposed electrically in series with one of said electrodes and/or in parallel with the electrodes, the semiconductor additionally or alternatively serving as the means for connecting the bridging conductor across the ends of the electrodes.
Inventors
- 👤 H Bendler
- 👤 H Rudolph
- 👤 U Brede
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 22:36
CPC Classifications
F; F42; F42B; F42B3/00; F42B3/10; F42B3/18; F42B3/185; F42B3/12; F42B3/124
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
127 words
A primer element for electrical ignition of an ignitable charge comprising a pair of electrodes supported in spaced relationship by an insulating support member, an ignitable bridge conductor electrically connected across said electrodes, said ignitable charge being in connection with said bridge conductor, and semiconductor means providing a resistance which varies in response to variation of the voltage applied thereto being disposed in circuit with said electrodes sO as to control the threshold level of voltage for ignition, said semiconductor means supporting said bridging conductor and including at least a first semiconductor element connected in parallel with said bridging conductor and having metallic coatings on opposite surfaces thereof, said bridging conductor being connected to said pair of electrodes via said metallic coatings on said first semiconductor element.
Claim 2
Dependent Claim
127 words
A primer element for electrical ignition of an ignitable charge comprising a pair of electrodes supported in spaced relationship by an insulating support member, an ignitable bridge conductor electrically connected across said electrodes, said ignitable charge being in connection with said bridge conductor, and semiconductor means providing a resistance which varies in response to variation of the voltage applied thereto being disposed in circuit with said electrodes sO as to control the threshold level of voltage for ignition, said semiconductor means supporting said bridging conductor and including at least a first semiconductor element connected in parallel with said bridging conductor and having metallic coatings on opposite surfaces thereof, said bridging conductor being connected to said pair of electrodes via said metallic coatings on said first semiconductor element.
Claim 3
Dependent Claim
23 words
A primer element as defined in claim 1, wherein said semiconductor means provides a resistance which decreases with increase of voltage applied thereto.
Claim 4
Dependent Claim
23 words
A primer element as defined in claim 1 wherein said semiconductor means provides a resistance which increases with increase of voltage applied thereto.
Claim 5
Dependent Claim
24 words
A primer element as defined in claim 1, wherein said semiconductor means includes a second semiconductor element connected in series with said bridge conductor.
Claim 6
Dependent Claim
24 words
A primer element as defined in claim 4, wherein said second semiconductor element provides a resistance which decreases with increase of voltage applied thereto.
Claim 7
Dependent Claim
24 words
A primer element as defined in claim 4, wherein said second semiconductor element provides a resistance which increases with increase of voltage applied thereto.
Claim 8
Dependent Claim
27 words
A primer element as defined in claim 4, wherein said first and second semiconductor elements each provide a resistance which decreases with increase in voltage applied thereto.
Claim 9
Dependent Claim
27 words
A primer element as defined in claim 4, wherein said first and second semiconductor elements each provide a resistance which increases with increase in voltage applied thereto.
Claim 10
Dependent Claim
58 words
A primer element as defined in claim 1, wherein said first semiconductor element is physically supported on said insulating support member, said pair of electrodes protruding through said support member being soldered to respective metallic coatings adjacent said support member and said bridging conductor being connected between said coatings at the other end of said first semiconductor element.
Claim 11
Dependent Claim
46 words
A primer element as defined in claim 1, wherein said semiconductor means provides a resistance characteristic which is related to the resistance of said bridging conductor such that ignition thereof occurs only after a predetermined value of ignition voltage has been exceeded by a predetermined amount.
Claim 12
Dependent Claim
39 words
A primer element as defined in claim 1, wherein said semiconductor means provides a resistance characteristic which is related to the resistance of said bridging conductor such that ignition thereof occurs only below a predetermined value of ignition voltage.
Claim 13
Dependent Claim
41 words
A primer element as defined in claim 1, wherein said semiconductor means provides a resistance characteristic which is related to the resistance of said bridging conductor such that ignition thereof occurs only between predetermined maximum and minimum values of ignition voltage.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-07-09 | 1977-01-08 | 1977-07-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-07-09 | 1981-01-08 | 1981-07-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-07-09 | 1985-01-08 | 1985-07-10 | $7700.00 | Window Closed / Lapsed |