Ammunition and explosives – Igniting devices and systems – Ignition or detonation circuit
Patent
1998-12-10
2000-07-11
Carone, Michael J.
Ammunition and explosives
Igniting devices and systems
Ignition or detonation circuit
102215, 102200, 1022027, F42C 1912, F42B 310
Patent
active
060856599
DESCRIPTION:
BRIEF SUMMARY
BACKGROUND OF THE INVENTION
This invention relates to an electronic detonator for initiating explosives and to a system which include one or more of the detonators.
The invention is concerned particularly with a system which enables detonators to be identified in the field, even though labels or identity markings on the devices may have been removed or obliterated, so that the detonators can be assigned definite time delays, wherein the integrity of the connections of the respective detonators to a blasting harness on site and under potentially live conditions can be rapidly and easily determined, and which offers a high degree of safety under live conditions to the personnel installing a blasting system.
DESCRIPTION OF PRIOR ART
Document EP-A-0588685 describes a detonator with an integrated electronic ignition module which includes a bi-directional communication circuit, an ignitor and an operating circuit. The ignitor is tested at a voltage which is substantially below a maximum non-trigger intensity threshold. The ignitor is protected against simultaneous failure of control transistors by means of a resistor. The system however does not cater for the situation which could arise if the resistor itself were to fail. The system does also not envisage the operation of the operating circuit, for firing the ignitor, at voltages which are above the maximum non-trigger intensity threshold voltage.
Document EP-A-0301848 describes a system wherein detonators are powered up individually before being loaded into blast holes, with explosives. Reliance is placed on the integrity of the electronic circuits for the prevention of accidents as well as on the fact that when an accident occurs the blasting cap would explode by itself and away from bulk explosives thereby reducing the possibility of harm to operators.
Document EP-A-0604694 describes a system wherein programming, arming, and firing sequences are controlled by a central control unit from a point of safety after a blasting system has been wired up. There is no description of the manner in which the individual detonators are tested for safety. No power is applied to the system until the whole system ha s been installed and wired to the central control unit. There is no description of operating the system at different voltage levels.
Document U.S. Pat. No. 4,674,047 describes a detonator which seemingly is preprogrammed under factory conditions with a time delay. No description is made of operating the detonator at different voltage levels.
Document U.S. Pat. No. 3,258,689 describes a fusehead testing method to determine the fire
o-fire limit of the fusehead. The technique described therein, although suited for testing carbon bridge fuseheads, is not suited for testing bridge structures produced in micro electronic processes.
SUMMARY OF THE INVENTION
An electronic detonator for initiating explosives which includes: a bridge firing element which is designed to be fired by a firing signal with a voltage which is greater than a designed no-fire voltage, a bi-directional communication circuit, and an operating circuit which is responsive at least to an operating signal at a voltage which is below the designed no-fire voltage, and which is characterised in that: voltage which is greater than a no-fire confirmation test voltage, voltage, which is any voltage in a first range of voltages which straddles the designed no-fire voltage, which is in the first range of voltages and which is below the designed no-fire voltage, being capable of generating the said firing signal for the bridge firing element but at a voltage which is less than the no-fire confirmation test voltage, and which is in the said first range of voltages and which is below the designed no-fire voltage, is in a state in which identity data, pertaining to the detonator, can be transmitted to or from the bi-directional communication circuit.
The bi-directional communication circuit may operate at any voltage in a second range of voltages which straddles the designed no-fire voltage.
The designed n
REFERENCES:
patent: 3258689 (1966-06-01), Ressler et al.
patent: 4649821 (1987-03-01), Marshall et al.
patent: 4674047 (1987-06-01), Tyler et al.
patent: 4869170 (1989-09-01), Dahmberg et al.
patent: 5214236 (1993-05-01), Murphy et al.
patent: 5520114 (1996-05-01), Guimard et al.
patent: 5894103 (1999-04-01), Shann
Beukes Christo Andre
Greyvenstein Ray Frederick
Patz Vivian Edward
Smithies Stafford Alun
Spiessens Rudy Willy Philomena
Bergin James S.
Carone Michael J.
Orica Explosives Technology Pty Ltd
LandOfFree
Electronic explosives initiating device does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Electronic explosives initiating device, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Electronic explosives initiating device will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-531143