Abstract: In a method of timing a multi shot blast, a plurality of explosive charges each comprising a programmable detonator arrangement 14.1 to 14.n are positioned at a blast site. At a control center 11, the desired times of the shots in the blast are programmed into a transportable firing tool 13 and the tool is carried to each detonator arrangement where a dedicated data path is established between the tool and each detonator arrangement, one after the other. The charges are fired by loading data regarding the times on which the detonator arrangements must cause their associated charges to explode into each detonator arrangement, individually. The detonator arrangements are allowed to process the data and to cause their associated charges to explode when according to a clock in the detonator arrangement and the data stored in the arrangement it is time for the charge to explode.

Abstract: An autonomous detonation device comprising an acoustic sensor, a logic circuit, and an output circuit. The invention is capable of discriminating the acoustic signal of an explosion of a primary charge such that it will detonate an explosive shortly thereafter. The invention further incorporates a delay system for safety purposes.

Abstract: The invention relates to a blasting apparatus for activating a plurality of electrical detonators after predetermined time delays. The blasting apparatus includes a plurality of remote electrical delay devices. Each device is linked to a detonator, and is arranged to be serially programmed with a timing signal, which originates from the central control unit and which determines the time delay. A bidirectional signal harness, having ends which terminate at I/O ports in the control unit, serially links the delay devices to the control unit. In the event of a fault of discontinuity occurring in the harness prior to programming of the delay devices, the discontinuity is detected and the direction of programming along the bidirectional harness is reversed so that those delay devices which, due to the break, cannot be programmed in the initial direction, are programmed with timing signals travelling along the signal line in the opposite direction.

Abstract: This system includes, in a projectile P bearing explosive warheads 2, 4, with their firing device 3, 5, impact detectors 1, an inertial unit 6 and a computer 7. The computer 7 determines, on the basis of the signals from the detectors 1, the instant of impact To and the angle of incidence I of the projectile on the target and, on the basis of the signals from the inertial unit 6, the speed V of the projectile at the instant of impact. Using the data V, I and the data on the type of target C, the computer 7 determines, in real time, the optimum delay with respect to the instant To for the firing of each warhead, and applies this delay to the firing command.

Abstract: An electronic detonator system 10 comprises a remote RF transmitter 11 and a transportable housing 12 comprising means 13 for charging energy storage means in the detonator 15 and means 14 for programming delay time means in the detonator. The programming means 14 and charging means 13 are connected to a connector 26. Detonator 15 comprises an antenna 29, a RF receiver 30, programmable delay time means 32, a switch 33, a fuse 34 and energy storage means 35. The delay time means 32 and energy storage means 35 are connected to a connector 28. In use, connector 26 is connected to connector 28 at the blast site and storage device 35 is charged and delay time means 32 is programmed. A fire command signal is then transmitted by transmitter 11 and after the delay time, switch 33 connects storage means 35 to fuse 34 thereby to energize the fuse.

Abstract: A plurality of magazines each receive an array of pyrotechnic devices. The magazines are latched to a fire control and support assembly which automatically engages the fire control circuit to each device of each magazine. The circuit ignites all devices of all the magazines in a given serial sequence. The system, under control of an operator, when turned off, may be restarted at the beginning of a selected sequence, at the point where the last device was ignited and continue the sequence or at selected different portions of devices. Different size devices can be ignited by one circuit having different magazines all coupled to one unit. Safety features also include delay ignition after startup and sounding an alarm before any device is ignited. A CPU is enabled by a fire command signal and disabled by internal programmed instructions. The CPU is periodically enabled in a device ignition cycle by external timing signals initiated by the CPU when enabled.

Abstract: A timing circuit includes a variable frequency oscillator which has a control signal that determines the output frequency of the oscillator. The control signal and a reference signal are stored in the circuit. A precision calibration pulse is applied to the timing circuit which counts the output cycles of the variable frequency oscillator during the period of the pulse. This count is stored and compared to the reference count to produce an error count. This error count is combined with the previously stored control signal to produce a new control signal that drives the output of the oscillator to a new frequency. The timing circuit can be utilized as a part of a delay circuit is an electronic blasting system wherein a control unit transmits the calibration pulse concurrently to each of the delay circuits to cause each circuit to calibrate its local oscillator in accordance with the calibration pulse. The control unit transmits a delay count to each of the delay ignition circuits.

Abstract: A program-controlled automatic ignition apparatus comprising: a number of ignition circuits for igniting explosive charges, a plurality of terminal control units 6a, 6b, 6c, . . . disposed in the vicinity of a location where explosive charges 17 are set, for managing divided groups of the ignition circuits, respectively, and controlling them individually, while monitoring the loaded state of the explosive charges 17 in the circuits, a central control unit 1 for controlling the ignition circuits through the terminal control units 6a, 6b, 6c, . . . according to the program so as to successively ignite them, and an interface unit 2 for transmitting instructions from the central control unit 1 to the individual terminal control unit.

Abstract: A remote controllable electronic detonator and a method of detonating an explosive charge are disclosed and claimed. The detonator comprises an antenna 16, a RF receiver 15, an energy storage capacitor 17, a switch 18, a delay time circuit 21 and a fuse 19. The method comprises the steps of transmitting to the detonator, by means of transmitter 11, a wave comprising a carrier amplitude modulated by a low frequency modulating signal, receiving the wave and utilizing energy in the wave to charge capacitor 17, enabling switch 18 by increasing the frequency of the modulating signal and communicating, by means of the wave, a fire command signal to the detonator. After a predetermined time delay, switch 18 connects capacitor 17 to fuse 19 thereby to energize the fuse.

Abstract: An explosive device receives signals specifying a unique communications address for use in a blasting circuit and a required blasting delay. The device has an electric igniter, but no independent power source which might cause accidental detonation. In an address and delay setting mode, when the device is being handled by a blaster, a unipolar signal is transmitted to the device to charge only a control power supply for general communications. In a blasting mode, a bipolar signal is transmitted to charge both control and igniter power supplies. A security code must, however, be transmitted to enable charging of the igniter power supply. Prior to detonation, each explosive device in a blasting circuit responds to a calibration signal by generating a timing circuit test count. A blasting machine processes nominal delays and test counts, and transmits adjusted delays to synchronize operation.

Abstract: A delay circuit for use in an electric blasting system including a capacitor for storing electric energy supplied from an electric blaster, an actuation circuit for detecting the stop of voltage supply from the blaster to generate an actuation signal, a circuit for generating clock pulses, a circuit for counting a predetermined number of clock pulses in response to the actuation signal to generate an igniting signal, and a switching circuit for responding to the igniting signal to discharge the electric energy stored in the capacitor through an igniting resistor, the actuation circuit having a zener diode with a threshold voltage. When the voltage supply from the blaster is stopped and the voltage across the zener diode becomes lower than the threshold voltage, the zener diode is cut-off to generate the actuation signal.

Abstract: A blasting system wherein the actuation of detonators at a plurality of blast holes is controlled by firing one or more test blasts and, at each blast hole, monitoring the resulting shock wave to derive data which is used to determine time delay criteria for the blast holes.Each detonator includes a shock sensitive device which detects the shock wave. Each detonator has on-board signal processing capability and optionally is connected to a central control computer.

Abstract: Electronic intervalometer circuitry utilizing a combination of mechanically ctuated switches and solid state logic components to carry out a predetermined program of deployment and sequential detonations of a plurality of underwater explosive charges.

Abstract: An apparatus for blasting comprises a series of electronically programmable detonators and an exploder, connected in series. The exploder communicates to the detonators at least programming and firing signals. The detonators are connected in such a way that programming signals will be received by a given detonator only when the adjacent detonator nearer to the signal output of the exploder has been programmed. This is preferably achieved by use of a connector associated with each detonator, the connector comprising a switching device which is operated by a logic element such that the logic element will operate on the switching device and allow signals to pass only when the detonator associated with that connector has been programmed.The apparatus permits the versatile and precise use of explosives, especially where large numbers of charges are involved.

Abstract: A delay type electric detonating primer for use in a multiple-step blasting system including a capacitor for storing electric changes supplied from an electric blaster via bus wires and leg wires, an actuation circuit connected across the capacitor for generating an actuation signal when an energy supply from the electric blaster is stopped, a clock pulse generating circuit having a crystal oscillator and being energized with energy stored in the capacitor to produce clock pulses, a counting circuit which is initiated to count the clock pulses in response to the actuation signal, and generates an ignition signal when the counter has counted the predetermined number of clock pulses, and a switching circuit for discharging electric charges stored in the capacitor through an igniting resistor in response to the ignition signal.

Abstract: System for the electrical sequential initiation of explosions comprising a series of initiating modules connected to one another and connectable to a power supply, and a corresponding series of electrically actuable initiators. Each initiating module is connected to an initiator and embodies a non-latching switch for actuating the initiator associated with that initiating module. The non-latching switch comprises a solid state electronic device having an emitter, a gate and a collector, and comprises a short circuit between the gate and the emitter for holding the device in an "off" state to a voltage applied to the collector. The device also comprises an open circuit between the gate and the emitter for turning the device "on" to a voltage applied to the collector, while a diode integrated on the device blocks a reverse supply voltage. The non-latching switch of each initiating module save the first in the series is connected to the initiator associated with the preceding initiating module in the series.

Abstract: A method of detonating explosive charges for the breaking of rock and ore comprises the use of two sets of components, one set within the explosive charge and the other set at the surface of the explosive. The set within the exposive comprises a detonator, a first delay element and a passive energy storage device such as a capacitor. The second set which is able to communicate with the first comprises a power source, a second delay element and a means for receiving signals from a remote command source. In a preferred embodiment, the first delay element has a fixed delay and the second delay element has a programmable delay.The method permits of versatility and precision in the use of explosives, using relatively inexpensive components.

Abstract: This invention provides modules and a system for sequentially activating a series of detonators. The modules and the system rely on a transistor in which the base-collector junction is caused to change state by a current pulse of suitable magnitude so that it presents a low resistance. Similarly, the base-emitter junction is also caused to change state to present a low resistance path in both directions. Such transistors are utilized to steer signals through a module in which they are used to activate a detonator associated with that module and then to steer a further signal to a next module in the series.

Abstract: A holder is disclosed for a mine fuze for an antitank mine, in which the mine fuze incorporates a booster charge, a detonator for initiating the booster charge, and a spring-biased firing pin for initiating firing of the detonator. The holder is dimensioned to fit into a mine-fuze location provided in the antitank mine, where the booster charge is in fuzed relationship with the explosive charge contained by the mine. The holder is also provided with connectors for initiators for initiating one or more explosive charges located in the ground, the booster charge being in fuzed relationship with the initiators when the holder and mine fuze are attached.

Abstract: An electronic delay detonator for igniting an ignition resistor a predetermined delay time after supply of electric power from a blasting machine comprises two input terminals for receiving the electric power supplied from the blasting machine, a diode-bridge circuit connected to the input terminals, a power supply capacitor connected to the output of the diode bridge circuit, an RC charging circuit connected in parallel with the capacitor and having a predetermined time constant, and a monolithic IC.

Abstract: An electrical firing arrangement for the sequential firing of a plurality of mortars stacked in end-to-end relationship within a single launching barrel. The firing arrangement comprises a pulse generator for producing mortar firing pulses and a circuit for applying these pulses to an electro-magnetic stepping switch which applies the pulses in turn over pairs of wires to igniters of the respective mortars as the stepping switch is stepped from one position to the next. The stepping switch comprises normally-open contacts which close when an operating coil is effectively energized by a firing pulse and switch wipers move out of engagement with one pair of associated contacts on the stepping switch towards the next pair of associated contacts on the same switch.

Abstract: A seismic geophysical prospecting method and apparatus is described involving the sequential shooting of lump explosive charges spaced apart in a borehole so as to produce seismic wave reinforcement in a given direction. Fast acting electronic switch means control the detonation of each charge responsive to the advance of the seismic waves front substantially independent of formation pressure wave velocity.

Abstract: For the chronologically staggered initiation of a plurality of electronic explosive delay detonators connected together with a blasting detonating machine, a signal current produced in each explosive detonator by signals sent by the blasting detonating machine, for example an impulse sequence, is integrated up in order to establish the delay time and, for carrying out of the delay, is integrated anew or integrated down to equality of the integrals or of the starting values. According to the invention, the integrating up begins in all explosive detonators simultaneously, with the end of the integrating up being controlled by signals from the blasting detonating machine.

Abstract: A circuit apparatus for operating firewirks ignition is used by connecting with a fireworks ignition circuit with a group of ignition ball terminals lined up as multi-step and multi-file coordinates of which the positive terminals are respectively connected with the common positive line of each file through a diode, and the negative terminals with the common negative line of each step.

Abstract: A remote control system including a central encoder for transmitting a single sequence of control pulses to a plurality of remote decoders, each of which performs a predetermined function when it has received a selected number of pulses. Reliability of the system is enhanced by including in the encoder and all of the decoders a number of electromechanical relays arranged in a special triple redundant configuration, such that no failure in any one relay can cause a decoder to perform its function at an undesired time or can prevent a decoder from properly performing its function at a desired time. In addition, the special use of supplemental relay contacts ensures that no failure of any solid state device in the encoder or decoders can cause a decoder to perform its function at an undesired time.

Abstract: A remote blasting system for exploding a number of explosives in a multiple-step manner including an oscillating unit for radiating an electromagnetic wave due to which A.C. currents are induced in receiving units some of which are directly connected to detonators and the remaining receiving units being connected to detonators via at least one switching unit which includes a switch and an actuating member for driving the switch. At the end of first excitation, the switch is closed and at the end of second excitation the detonator is blasted via the closed switch.

Abstract: This invention relates to sequential blasting utilizing electronic circuitry to steer detonating pulses to successive detonators. Modules are provided which contain a two-terminal element that has the characteristic that in its first normal state it has a high resistance in at least one direction and it may be changed into a second state in which it has a low resistance in both directions by a suitable pulse. Further, a detonating signal does not flow from one power line to the other through the particular module that is being addressed, but from one side of one module through a connecting link and then through the other module. Thus, each module has an input steering terminal and an output steering terminal, with the output steering terminal of each module connected to the input steering terminal of the next module.

Abstract: The technical area of this invention is initiation delay mechanisms for warheads carrying two tandem-mounted shaped charges.With this invention the initiation delay mechanism consists of using the movement of a screen placed between the forward charge 1 and the rear charge 2. According to a specific characteristic, as it moves, the screen can close an electric circuit by means of contactors placed in a given position. According to other variants, the screen can impact piezoelectric components generating energy or, in the case of a magnetic screen, can cross an induction coil.Application in the field of projectiles and, particularly, of rockets and missiles.

Abstract: Detonating apparatus comprises a plurality of multichannel exploders (MCEs) connected to a control unit which provides an operator/apparatus interface remote from the MCE's detonator circuits. MCEs measure integrity, resonant frequency and impedance at resonance of the detonator circuits connected to each channel, and are thereby programmed to give optimum firing current at the resonant frequency. The control unit provides electrical power, interrogates the MCEs on the status of their detonator circuits, and gives firing signals to be obeyed by MCEs after predetermined delays.

Abstract: A method and system for selecting and arming each of a plurality of firing modules in a single-line selective perforating system is disclosed. A single firing line connects each firing module one at a time in a sequence to a control unit to receive power and control signals therefrom. Each module generates internally a module active time interval in response to being connected to the firing line power. Each time interval has a first portion during which the module generates an identification pulse to the control unit to uniquely identify that a particular module has been connected to the firing line, and a second portion during which the module is enabled to receive a selection pulse from the control unit to terminate further sequencing of the modules to locate the module to be selected. The next module to receive power from the control unit is connected to the firing line by a pass-through switch in the last connected module at the end of its active time interval if that module was not selected.

Abstract: A method and system for selecting and arming each one of a plurality of firing modules in a single-line selective perforating system is disclosed. A single firing line connects each firing module one at a time in a sequence to a control unit to receive power and control signals therefrom. Each module generates internally a module active time interval in response to being connected to the firing line power. Each time interval has a first portion during which the module generates an identification pulse to the control unit to indicate that another module has been connected to the firing line, and a second portion during which the module is enabled to receive a selection pulse from the control unit to terminate further sequencing of the modules to locate the module to be selected. The next module to receive power from the control unit is connected to the firing line by a pass-thru switch in the last connected module at the end of its active time interval if that module was not selected for firing.

Abstract: A sequential blasting system includes a plurality of electrically fired detonators and a pyrotechnical activated switch associated with each detonator. On firing of a detonator, the associate pyrotechnical activated switch primes the sequentially next to be fired detonator. Alternate detonators are connected to first and second conductors, respectively, through an alternating sequencer, which sequencer alternatingly connects the first and second conductors with a source of electrical power to fire the detonator primed by the previously actuated pyrotechnical activated switch.

Abstract: The invention relates to improved systems and methods for selectively firing perforating guns in well bores and is concerned primarily with the production of a positive confirmation to the effect that each actuation at the operator control station intended to cause a firing of a particular shaped charge did or did not in fact result in the firing of that shaped charge. Such positive confirmation is accomplished by methods which involve the passage of measuring current from a constant current source through certain conductive loops to develop signals that are a function of the conductive loop resistance, the storage and comparison of said signals, and the display of resultant information. Due to certain phenomena, satisfactory measurement results will not be achieved unless a measuring current of substantial magnitude is used. The various parameters involved are treated.

Abstract: A solid state switch for electro-explosive devices. Fundamentally, the switch includes a matrix of transformers, each having a center-tap primary winding and a grounded secondary winding, the secondary having a bridge wire connected thereacross. Power gating circuitry is provided for applying a DC voltage to the center-tap primary of all transformers in a selected row. A pair of transistors are connected through diodes to opposite ends of all of the primary windings of the transistors in each column. A driver alternately gates the pair of transistors of a selected column into and out of conduction such that the current through the primary of the transformer common to both the selected row and selected column is of alternating direction, inducing an AC current into the associated secondary winding. The bridge wire of the secondary is thus energized by an AC current.

Abstract: An antipersonnel mine is shown, a plurality of such mines being adapted to be loaded into a round of ammunition for dispersal and subsequent detonation at random instants. The timing for detonation of each mine is determined by the discharge of a capacitor, starting when dispersal occurs. The condition of the explosive lead of each mine before loading is indicated by a position indicator in the safing and arming mechanism.

Abstract: A pyrotechnic system comprises a plurality of pyrotechnic charges or devices 20 arranged in a matrix of recesses 14 formed in a block 12 of a synthetic resin material.In one embodiment, each device 20 contains a fast-burning pyrotechnic composition 42 arranged to be fired by an electrical primer 50, for producing a flash and/or a bang, and a slow-burning pyrotechnic composition 40 separated from the composition 42 and arranged to be ignited by the firing of the composition 42. Embedded in the composition 40 is a fine wire loop 48 which is ruptured by the burning of the composition 40. The primers 50 of the devices 20 are connected in parallel between two input terminals 52, 54, and each loop 48 is connected to short-circuit the primer 50 of the next device 20 in the firing sequence. The pyrotechnic system is thus self-sequencing.

Abstract: Separate electrical timing and load activation devices are provided for each of plural electrical loads and each device is connected to receive reference timing signals from a central unit. Each of the separate timing and load activation devices measures a reference time interval accurately defined by the reference timing signals and subsequently activates its associated electrical load after a respectively corresponding predetermined time delay which is determined as a function of the locally measured reference time interval.

Abstract: A circuit for use in the sequential initiation of explosives comprises an up-down counter having a first input terminal at which an up-count is initiated, a second input terminal at which a downcount is initiated, and an output terminal, an energy storage capacitor for powering the counter, a first resistor which has a low impedance for a fixed time to current of a particular value and of a first polarity and which thereafter has a high impedance connected to one of the input terminals of the counter so that when current of the first polarity and of the particular value is passed through the first resistor a signal is applied after the fixed time to the input terminal to initiate a count in an up direction, and a second resistor which has a low impedance to a predetermined voltage of a given polarity connected to the other input terminal of the counter so that when the predetermined voltage of the given polarity is applied to the second resistor a count is initiated in a down direction, the counter generating

Abstract: A multiple payload cartridge connectible to a source of firing signals by two connecting wires having a first and a second branch each having a squib therein connected in parallel across the connecting wires is characterized by a zener diode connected in series with the second squib in the branch containing the same. The zener diode prevents the flow of current through the branch with the second squib until a firing signal of a predetermined polarity and a magnitude greater than the breakdown voltage of the zener diode is applied across the second branch. The zener diode responds to that firing signal by breaking down into a low resistance conduction path to thereby permit an electrical current sufficient to raise the second squib to incandescence to flow therethrough.

Abstract: An intervalometer for use with airborne rocket launchers having a switch assembly with a multiplicity of switch positions relating to the rockets. A solenoid assembly moves the switch assembly sequentially through switch positions for distributing firing current to the rockets. An electronic timing circuit energizes the solenoid assembly for a fixed time duration independent of variations in and characteristics of the solenoid assembly. At the termination of that fixed timed duration (1) a firing current pulse is applied to an individual rocket and (2) an additional fixed time duration independent of the solenoid assembly is initiated by the timing circuit. At the termination of the additional time duration, the timing circuit again energizes the solenoid assembly and the sequence continues. In this way there is achieved a time between leading edges of sequential firing pulses which are consistent, accurate and independent of solenoid assembly characteristics.

Abstract: A multiple payload cartridge employing circuit components in the squib portion thereof to allow for separate or sequential firing thereof, and hence separate payload ejection, through two-wire connections. Various techniques include the use of a repositionable switch to provide sequential ground connections; the use of mechanical interrupters, e.g., spring-type, crushable-element-type or domed-pop-action type; the use of resistive voltage dividers to permit discrimination in squib firing via applied voltage amplitudes; the use of diodes to permit discrimination in squib firing via applied voltage polarities; and combinations of the above.

Abstract: This invention provides a method and apparatus for electrically, sequentially activating a sequence of initiators, to sequentially initiate a series of explosions, such as in blasting or with propellants. The invention provides a series of activating modules that each has a switch which is disabled by the preceding activating module until the initiator of the said preceding module has been activated. The activating modules are further arranged in sets so as to be selectively energized from a suitable power supply. In a preferred form the switches are uni-directional and the activating modules are connected between a pair of supply cables with the switches of alternate modules being of opposite polarity. The activating modules are then selectively energized by reversing the polarity of the power supply. In an alternative form the activating modules are connected to have a common power return cable with the activating modules of each set being connected to individual power drive cables.

Abstract: Separate electrical timing and load activation devices are provided for each of plural electrical loads and each device is connected to receive reference timing signals from a central unit. Each of the separate timing and load activation devices measures a reference time interval accurately defined by the reference timing signals and subsequently activates its associated electrical load after a respectively corresponding predetermined time delay which is determined as a function of the locally measured reference time interval.

Abstract: An electrical system for launching separate salvos, comprised of squibs, jectile bombs or the like, at different times but at the same launch location from a remote position using a single electrical control wire for carrying the current. The system is comprised of a negative polarity relay and a positive polarity relay respectively connected with a first and second salvo, a power supply comprised of two 24 volt batteries supplying power to the circuit from opposite terminals, a selecting switch connected with the batteries to select either positive or negative current to match the relay and salvo desired to be fired, an ignition switch for closing the circuit and a single control wire running from the ignition switch to the relays carrying the positive or negative current required for launching the chosen salvo.

Abstract: An electrical system which serves to control the firing of multiple grenade aunchers. The system generates multiple coded tone pairs for up to sixteen launchers which are provided to the launchers through a +28VDC line connected to the vehicular power supply. The tone pairs are decoded enroute to each launcher which exercise a firing circuit triggering the grenade launcher's firing squib causing the grenade to launch.