US3603844A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electronic delay multiperiod initiating system
Assignee: Ireco Inc
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Filing: 1969-07-31
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Granted: 1971-09-07
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Expires: 1989-07-31
Abstract
Abstract A device for providing electronically delayed multiple point initiating current to electrical initiators in blasting circuits is provided. The device has a plurality of firing circuits each of which employs a firing capacitor connected to a silicon controlled rectifier. A plurality of buffer circuits connected in parallel are provided, each buffer circuit having at least one capacitor which is connected to the control gate of a silicon controlled rectifier of a firing circuit. A timing circuit sequentially actuates discharge of each buffer capacitor into the gate of the silicon controlled rectifier of a corresponding firing circuit whereby the silicon controlled rectifier is made conductive allowing the firing capacitors to discharge into the firing circuit.
Inventors
- 👤 Fred A Fritz
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 00:09
CPC Classifications
F; F42; F42D; F42D1/00; F42D1/04; F42D1/045; F42D1/05; F42D1/055; G; G01; G01V; G01V1/00; G01V1/02; G01V1/04; G01V1/06; G01V1/08; H; H03; H03K; H03K17/00; H03K17/28; H03K17/292
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
222 words
A device for providing electronically delayed multiple point initiating current to electrical initiators of a blasting circuit for initiation thereof, said system comprising a. a plurality of firing circuits connected in parallel between a first DC power source and a common base connection, said firing circuits comprising resistance means, blocking diode and firing capacitor connected in series and a silicon controlled rectifier having an anode, cathode, and control gate, said firing capacitor being charged through the resistance means by the first DC power source to the potential desired in the blasting circuit, one lead of the firing capacitor being connected to the cathode of the silicon controlled rectifier, the anode of the silicon controlled rectifier being connected to the blasting circuit, b. a plurality of buffer circuit means connected in parallel between a second power source and the common base connection, each buffer circuit means comprising at least one buffer capacitor connected to the gate of the silicon controlled rectifier of the firing circuit, said buffer capacitor being charged by the second DC power source and c. timing circuit means connected to each of the buffer circuit means for sequentially actuating discharge of the buffer capacitors into the firing circuits whereby the silicon controlled rectifiers in the firing circuits are made conductive thereby sequentially discharging the firing capacitors into the blasting circuit.
Claim 2
Independent Claim
222 words
A device for providing electronically delayed multiple point initiating current to electrical initiators of a blasting circuit for initiation thereof, said system comprising a. a plurality of firing circuits connected in parallel between a first DC power source and a common base connection, said firing circuits comprising resistance means, blocking diode and firing capacitor connected in series and a silicon controlled rectifier having an anode, cathode, and control gate, said firing capacitor being charged through the resistance means by the first DC power source to the potential desired in the blasting circuit, one lead of the firing capacitor being connected to the cathode of the silicon controlled rectifier, the anode of the silicon controlled rectifier being connected to the blasting circuit, b. a plurality of buffer circuit means connected in parallel between a second power source and the common base connection, each buffer circuit means comprising at least one buffer capacitor connected to the gate of the silicon controlled rectifier of the firing circuit, said buffer capacitor being charged by the second DC power source and c. timing circuit means connected to each of the buffer circuit means for sequentially actuating discharge of the buffer capacitors into the firing circuits whereby the silicon controlled rectifiers in the firing circuits are made conductive thereby sequentially discharging the firing capacitors into the blasting circuit.
Claim 3
Dependent Claim
116 words
The device of claim 1 wherein the buffer circuit means comprises a resistance means connected in series with the buffer capacitor, a second silicon controlled rectifier having an anode, cathode and control gate, and a blocking diode having an anode and a cathode, the anode of the second silicon controlled rectifier being connected to the junction of the resistance means and buffer capacitor, the anode of the blocking diode being connected to the cathode of the second silicon cOntrolled rectifier, the cathode of the blocking diode being connected to the control gate of the silicon controlled rectifier of the firing circuit, said buffer capacitor being charged through said resistance means by the second DC power source.
Claim 4
Dependent Claim
223 words
The device of claim 2 wherein the timing circuit means is comprised of plurality of timing circuits connected in series, said timing circuits comprising a first variable resistance means and timing capacitor connected in series, a Shockley diode, having an anode and a cathode, and a third silicon controlled rectifier having an anode, cathode and control gate, the anode of the Shockley diode being connected at the junction of the timing capacitor and first variable resistance means and the cathode of the Shockley diode being connected to the control gate of the third silicon controlled rectifier, the cathode of the third silicon controlled rectifier being connected to the control gate of the second silicon controlled rectifier of the succeeding buffer circuit and to the variable resistance means of the succeeding timing circuit; the anode of the third silicon controlled rectifier being connected to a third DC power source, the timing circuit being activated upon application of the third DC power source whereby potential is built up on the timing capacitor until the avalanche breakdown voltage of the Shockley diode is exceeded whereby voltage is applied to the control gate of the third silicon controlled rectifier making it conductive and permitting current to flow to both the silicon controlled rectifier of the succeeding buffer circuit making it conductive and to a succeeding timing circuit.
Claim 5
Dependent Claim
24 words
The device of claim 3 in which a radio frequency suppression circuit is connected between said first DC power source and the firing circuit.
Claim 6
Dependent Claim
97 words
The device of claim 4 in which the radio frequency suppression circuit comprises a switching means, a first resistance means and at least one inductor connected in series with the first DC power source, a plurality of capacitors connected in parallel between the first DC power source and the common base connection, each capacitor having one lead thereof connected to a lead of each inductor, a second and a third resistance means connected in series across the switching means, and another capacitor connected between the common base and the junction of the second and third resistance means.
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) | 1974-09-06 | 1975-03-08 | 1975-09-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-09-06 | 1979-03-08 | 1979-09-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-09-06 | 1983-03-08 | 1983-09-07 | $7700.00 | Window Closed / Lapsed |