Abstract: An apparatus for igniting a plurality of detonating primers including an oscillator for generating a microwave, a transmitting antenna for radiating the microwave generated by the oscillator toward receiving antennas connected to the detonating primers, and a shield housing provided between the transmitting antenna and the receiving antennas to surround a microwave propagating space. The shield housing is constructed such that the microwave radiated by the transmitting antenna is not leaked out of the shield housing and spurious electromagnetic waves do not intrude into the space within the shield housing. The detonating primers are positively ignited by the electric power radiated from the transmitting antenna and received by the receiving antennas even if the output power of the oscillator is small. The shield housing also serves to confine noise, scattering stones and fumes within the shield housing.

Abstract: An exploding foil bubble activated detonator, adapted for use in a perforating gun, includes an exploding foil, the exploding foil including as neck section which vaporizes when a current of sufficient magnitude and duration flows therethrough, a layer of polyimide material deposited over said foil, and a spacer layer deposited over said layer of polyimide material, the spacer layer including a guiding hole disposed directly over the neck section of the foil. When the current flows through the neck section of the foil, a turbulence is caused to occur directly above the neck section. This turbulence causes a portion of the polyimide material to expand to form a bubble. The bubble is shaped and sized by the guiding hole in the spacer layer which is disposed directly over the neck section of the foil. The shaped and sized bubble in the polyimide material impacts an explosive thereby detonating the explosive.

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 metal detonator housing has a central opening extending therethrough between upper and lower ends and a detonator located in the opening at the lower end. Two leads are conencted to the detonator for causing the detonator to explode upon the application of electrical energy to the two leads. A metal contact spring is located in the opening of the housing at the upper end and extends out of the upper end. The contact spring is electrically insulated from the housing. A spring is located in the opening of the housing and is coupled to the detonator for urging the detonator toward the lower end. One electrical leads extends from the detonator through the central opening of the housing and is electrically connected to the contact spring. The other electrical lead is electrically coupled to the housing.A shunting wire is provided with means for removably attaching one end of the shunting wire to the outside of the housing with the other end of the shunting wire being removably connected to the contact spring.

Abstract: An apparatus for testing ignitability of an initiator includes a body having a central cavity, initiator holder for holding the initiator over the central cavity of the body, an ignition material holder disposed in the central cavity of the body and having a cavity facing the initiator holder which receives a measured quantity of ignition material to be ignited by the initiator and a chamber in communication with the cavity of the ignition material and the central cavity of the body, and a measuring system for analyzing pressure characteristics generated by ignition of the ignition material by the initiator. The measuring system includes at least one transducer coupled to an oscillograph for recording pressure traces generated by ignition.

Abstract: A system for aiming a selectively aimable warhead (SAW) at a target by exsively deforming the warhead into a shape desirable for directionality. Twenty-four explosive forming charges are located around the circumference of the warhead and run the entire length of the warhead. The proximity fuze selects one sector out of 24 as the direction aim. Having selected a sector in the azimuth, the forming charge in that sector plus the adjacent two forming charges are initiated simultaneously. After a time delay interval sufficient to allow the warhead to deform (about 1/2 millisecond to 1 millisecond), warhead boosters located furthest from the target (or 180 degrees from the forming charges) and on each end of the warhead, are initiated simultaneously. The warhead is detonated generating a high velocity fragment beam towards the target.

Abstract: A method and apparatus for achieving adiabatic heat ignition of combustible material, particularly explosive compositions which involves entrapping a quantity of gas in a chamber which is in communication with the combustible material and suddenly compressing the gas to the extent that the temperature thereof is increased adiabatically to the ignition temperature of the combustible material. The apparatus is particularly adaptable for use as an adiabatic ignition device for detonating cord and shaped charges of perforating guns for completion of wells. A quantity of high explosive within an explosive barrel is in detonating proximity with the detonating cord. A cylinder forms an air chamber which is in communication with the explosive composition and is provided with a piston for compression of the gas. One or more shear pins or other locking devices are provided to secure the piston in immovable relation with the cylinder.

Abstract: A method for manufacturing explosive logic circuit trails using conventio silk screening techniques. Silk screening is used to build up both the explosive trail, as well as the inert substrate. This is accomplished one layer at a time onto a circuit base material. The explosive logic circuit herein is reliable, cost efficient and relatively easy to produce. The invention herein encompasses both the method of manufacturing said explosive logic circuits and the circuits themselves.

Abstract: A pyrofuze ordnance arming system, for air delivered ordnance, which provs a removable physical barrier to prevent the premature operation of ordnance device arming activation systems. An electrothermally initiated, alloyably removable pyrofuze pin extending from a pyrofuze device is employed as a physical barrier in an arming system to replace the conventional arming wires. The system increases safety and reliability for ordnance arming while decreasing the complexity and labor involved in preparing and loading ordnance on aircraft.

Abstract: In the field of blasting, it is often desirable to ignite explosives at various relative times. Such delayed ignition can have advantages in better break up of rock and reduced ground vibration. A principle problem in using the time delay technique is the accuracy rate of a local oscillator which measures the delay time for each of the delay circuits. In the described system, a calibration interval, independent of any delay time, is transmitted from a control unit concurrently to each of the delay circuits wherein each delay circuit counts the output of its local oscillator during the calibration interval. This local oscillator output is then compared to a predetermined reference count, either at the delay circuit or at the control unit, and a correction factor is established. This correction factor is then applied to a delay count for the individual delay circuit.

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: A conducting composition for detonators having insensitivity to one amp of current or one watt of power comprising 40 to 80 parts by weight of lead styphnate 2 to 10 parts by weight of carbon black or graphite and the balance being lead oxide. Firing times of less than eight milliseconds can be achieved where at least one percent of graphite is included in the composition.

Abstract: Explosive charges are detonated by remote control in environments having high levels of extraneous electric and electromagnetic energy by providing a separate control unit for each explosive charge. The control unit accepts coded commands radio transmitted from a command unit and, if those commands meet with pre-set criteria, the control unit detonates the charge. Each control unit is connected to its respective explosive charge by electrical or optical conductors providing sufficient separation as to allow the control unit to survive detonation of the charge without damage.

Abstract: A firing unit for initiation of detonators, which contain at least one base charge in a detonator casing, which firing unit comprisesan electrically actuable fuse head,a current source connected to the electrically actuable fuse head via switching means, and an electronics unit comprisinga signal decoder designed so as to distinguish a start signal supplied to the detonator via an external signal conductor,a delay circuit designed in such a way that, when the start signal is received, it supplies an ignition signal after a predetermined time andthe switching means, which are designed in such a way that, when the ignition signal is received, they connect the current source to the fuse head in order to electrically actuate the latter,the electronics unit comprising at least one chip made from a semiconductor material and having a microcircuit. According to the invention, at least the chip and an additional component are electrically and mechanically connected on a substrate having a circuit pattern.

Abstract: An actuator for use in conjunction with a detonator for blasting comprises electronic circuitry which on receiving input signals generates an output arm signal to arm a detonator, and then after a predetermined delay an output actuate signal to fire the detonator and an associated explosive charge. The delay is capable of being remotely and precisely set. The actuator is preferably used in conjunction with a control device which has a microcomputer whose memory contains arm and actuate codes and which has both arm and actuate keys. This microcomputer is such that the actuate keys must be operated within a predetermined period after operation of the arm key, otherwise an actuate signal is not transmitted to the actuator.

Abstract: An apparatus for electrically blasting a number of electric detonators arranged at a plurality of working faces, including a single controller having a power source unit for supplying a D.C. voltage and a plurality of ignition control units for selectively applying the D.C. voltage; a plurality of oscillators each arranged near respective working faces, the number of the oscillators corresponding to that of the ignition control units, each oscillator being energized with the D.C. voltage to generate a high frequency current and being connected to respective ignition control units via an electric wire bundle; and a plurality of lead wires each connected to outputs of respective oscillators. Loop-like leg wires of electric detonators are electro-magnetically coupled with the lead wires with the aid of transformer magnetic cores.

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: A multipoint initiation system for an explosive including a stripline head and a plurality of detonators fixed to the head at predetermined locations. The head and detonators are embedded in the explosive without a mechanical safe-arm device. Electrical connections in the head provide for independent detonation of the detonators.

Abstract: A detonator firing element which includes a miniature energy dissipation device located on a substrate which forms part of an integrated electronic circuit. An explosive or pyrotechnic compound is exposed to the effects of energy dissipated by the device. The device may be resistive, be formed by a semi-conductor device, or be a field effect device. The integrated circuit includes timing, testing, control, communication and interlock circuits to implement stand alone or computer controlled blast systems. Protection against over-voltages and induced currents is provided. Due to the integrated circuit approach power consumption is kept to a minimum and a detonator incorporating the firing element can be powered for a substantial time period by an energy storage device such as a capacitor.

Abstract: A process and an apparatus for automatically positioning an explosive charge at a predetermined position above the surface of the snow for setting off an avalanche.The apparatus includes an electric winch for unwinding and rewinding a suspension string attached to the explosive charge. The winch is swingably mounted in a container of the apparatus in a manner so as to oscillate between up and down positions depending upon whether the string is tensioned or not. Magnetic detectors associated with the winch count and signal the number of turns of its drum to a programmable electronic unit. Coded wheels are provided to select a maximum height of descent and a lifting height for the charge after contact with the snow.

Abstract: A method and apparatus for indicating the time-break on a seismic record wherein the time-break is marked in response to the rupture of an electric circuit by the explosive charge used to generate the seismic waves. The preferred rupturable electric circuit is connected to the same energy source as the electric detonator used to initiate the explosive charge and the preferred electric detonator is one connected to a high frequency A.C. firing energy source through a transformer, the rupturable electric circuit being the primary or secondary circuit of the transformer.The method is more accurate than the present method of marking the time-break at the initial application of current to the detonator.

Abstract: A method for implementing an operational or functioning test on electrically-actuatable ignition or detonation-triggering circuits for ammunition, wherein the circuits are arranged on board the ammunition. Moreover, also disclosed is an arrangement for the implementation of an operational test of electrically-actuatable ignition or detonation-triggering circuits for the ammunition, wherein the circuits are arranged on board the ammunition.

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 loop portion of a bus wire connected to an electric blasting device is passed through a first magnetic core together with a first loop-like wire, and the first loop-like wire is further passed through a second magnetic core provided in a detonator. The detonator includes a second loop-like wire which is passed through the second magnetic core, an electric bridge connected to the second loop-like wire and a fuse head provided around the electric bridge. When a pulsatory high frequency current is supplied to the bus wire, high frequency currents are induced in the first and second loop-like wires by electromagnetic induction. Then the current flows through the electric bridge of the detonator to fire the primer explosive.

Abstract: The present invention comprises a detonating cord of polygonal cross section having three or more substantially flat sides of substantially equal length and substantially equal included angles between each of the sides.

Abstract: A running time display for a projectile time fuze uses a digital display visible through a transparent window in a nose of the projectile. The fuze running time can be programmed either electrically by a receiving coil within the nose or manually by a time setting ring on the surface of the nose. To facilitate a running time display during adverse visibility conditions, the display may comprise LED elements with the display elements being intermittently energized to reduce electrical power consumption from a battery powering the time fuze.

Abstract: A weapon control for a droppable weapon such as a bomb, has at least two sors for producing impact related or environment related signals for a microcomputer forming part of the weapon. The microcomputer evaluates the signals received from the sensors for producing different control signals for different situations as signified by the sensor produced signals. If the weapon has hit a hard target surface the responsive control signal detonates the weapon instantly. If the weapon got stuck in a soft target, the weapon is placed into a lurking state for a later detonation or defusing.

Abstract: An inductive coupling device is provided wherein the transmission of energy through the device is controlled by the application of a steady magnetic field within the magnetically permeable core of the device, transmission being inhibited at high magnetic field intensity and restored when the magnetic field intensity is reduced to a low value. The device is especially advantageous for the safe coupling of ignition elements, such as blasting detonators, to an a.c. firing energy source.

Abstract: Low level remotely generated control signals are amplified at a local ignition site using a local power source and the amplified control signals are used to charge a local energy storage device. Thereafter firing control signals (e.g., controlled duration suppressions of the remotely generated control signals) are detected and used to control discharge of the thus stored energy through an electrical ignition device.

Abstract: A detonation system for use with supply of electrical energy has user operable firing console for selectably transmitting unit identification information, firing delay time information and selections from a command set including Output, Delay, Fire (Time), Abort, Power Up (Arm), Input, and Store. The console displays responses or information digested from responses by electrical delay detonators to the commands. The detonators have explosive, a capacitor for storing energy from the supply to set off the explosive, circuitry for charging the capacitor from the supply and transferring the energy from the capacitor to the explosive in response to first and second signals generated in response to the commands. Each detonator can be programmed with a unique identification number and delay time. The time base in each detonator can be compensated so that errors in the time base are obviated so as to achieve the correct delay.

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 programmable electronic delay fuse for initiating a firing after a programmed and accurate delay time has been chosen, comprising a fire control unit (FCU), a programming unit (PU) to program and test the fire control unit (FCU), and optical coupling interface means (1) on each unit to electrically interconnect firing and status means (3) on the fire control unit (FCU) with command and test means on the programming unit.

Abstract: The invention is a detonator for use with high explosives. The detonator comprises a pair of parallel rail electrodes connected to a power supply. By shorting the electrodes at one end, a plasma is generated and accelerated toward the other end to impact against explosives. A projectile can be arranged between the rails to be accelerated by the plasma. An alternative arrangement is to a coaxial electrode construction. The invention also relates to a method of detonating explosives.

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: The present invention is an improved waterproof quick match and apparatus and method of making same in which the loose fitting central core (fuse) covering is made of a plastic coated paper and heat sealed at the seams in a waterproof relationship.

Abstract: A number of detonating primers are electrically blasted by supplying a high frequency current through a bus wire formed by a pair of parallel conductors connected to each other at distal ends and having a constant impedance with which bus wire loops connected to the detonating primers via leg wires are electromagnetically coupled via a number of magnetic cores having slits formed therein. At first, one or more loops are inserted into respective magnetic core through the slit and one of the parallel conductors is also inserted into the magnetic core through the slit. When the high frequency current having a frequency from 100 KHz to 1 MHz is passed through the conductors of bus wire in opposite directions, there is induce electromagnetically secondary high frequency currents in respective loops, which are supplied to respective detonating primers for explosion.

Abstract: An improved arming and firing device especially suited for rocket motors. An explosive donor charge is packed against a bulkhead formed in the body of the device. Shock energy generated by the donor charge and transmitted through the unruptured bulkhead sets off a shock-responsive receptor charge, which in turn initiates a pyrotechnic or explosive rocket motor-actuating output charge. The bulkhead prevents blow-by or leakage of the rocket's combustion products. The donor charge is ignited by an electrically activated detonator. The detonator is carried by a moveable holder. The holder is moved against a return spring by electromechanical driving means. Arming the device is accomplished by moving the holder to position the detonator in firing train with the donor charge, thereby simultaneously bringing electrical contacts on the detonator into contact with electrical leads on a switch plate located adjacent the holder and thus closing the firing circuit.

Abstract: A microcomputer controlled electronic fuze capable of surviving a hard tat impact is disclosed comprising two epoxy potted printed circuit boards mounted back to back of which one of the boards is designed to survive impact and contains the microcomputer controller, storage charge, timing circuit, and fire pulse detonator circuit. The other board carries an electric motor drive circuit for mechanical timing and detonator alignment, a detonation delay command storage circuit, and an AC rectifier and voltage regulator circuit coupling a wind turbine generator power supply to the fuze.

Abstract: An arming device is interposed in the electrical circuit between the electrical switch at a control site and a remote explosive. The arming device is physically located near the explosive and is connected by a fluid pressure line to a pressure source at the control site. Until such time as the arming device is activated, the danger of premature detonation of the explosive from current induced in the conductor between the explosive and the switch is eliminated, and the fluid-pressure controlled arming device is not susceptible to such induced current. Both piston and diaphragm-type arming devices are disclosed.

Abstract: The invention relates to a radio remote blasting system. The subject blasting system includes a portable remote controlled detonation system comprising a tone generating pad employed to generate a coded signal received at a blasting site by a receiver decoder detonator to enable detonation to occur by conventional means, also a radio telephone used to encode signal frequencies for use in enabling an explosive detonating device and allowing two way communication.

Abstract: A cased cartridge ammunition ignition booster includes a film of booster propellant that is case-bonded without insulation or liner to the inside wall and base of an ordinary brass, steel or plastic cartridge case and ignited by a conventional primer. Flame spread occurs from the case wall inward through the non case-bonded propellant bed, that is, the bed of the propelling charge.

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 low cost igniter comprising a multi capsule of low strength, non-porous material, such capsule being divided into at least two separate compartments. One of such compartments is filled with a freezable fluid, and another contains an ingredient that will function in the presence of a selected ingredient to bring about combustion. The ingredient in the capsule is disposed in the immediate vicinity of the second ingredient, so that on the occasion of a freezing temperature, the freezable fluid in the compartment of the capsule will freeze and expand, fracturing all components of the capsule substantially simultaneously, thus leading to a combination of the first and second ingredients, as will bring about immediate combustion. When the multi capsule is configured to have two compartments, the second ingredient is contained adjacent the capsule, but when the multi capsule has three compartments, the freezable fluid as well as both ingredients are each sealed in separate compartments of such capsule.

Abstract: A method for loading explosive charges into blastholes in a subterranean formation for forming a fragmented permeable mass of formation particles in an underground cavity in the formation is provided. Upper and lower voids spaced apart vertically from each other by unfragmented formation are excavated into the subterranean formation. A generally vertical blasthole is formed in the unfragmented formation between the voids. Upper and lower explosive charges, separated from one another by stemming, are formed in the blasthole. Each such explosive charge includes at least one primer operationally connected to an explosive initiating lead that extends from the charge. The explosive initiating lead of the upper explosive charge extends from the top of the blasthole into the upper void and the explosive initiating lead of the lower explosive charge extends from the bottom of the blasthole into the lower void.

Abstract: In combination: an explosive propulsion member having an axial percussion primer; an electric primer mounted to discharge toward the percussion primer along the axis; and apparatus between the primers hydrodynamically responsive to discharge of the electric primer to percussively engage the percussion primer.

Abstract: The detonation gas for gas-detonatable blasting charges used in surface mining and the like is supplied by a portable self-contained delivery unit connected to the blasting charges by a network of small flexible tubing, which unit blends pressurized fuel and oxidizing gases from separate supply sources in predetermined proportions and regulates the separate flows of such gases in response to the backpressure imposed by the tubing network to maintain such proportions in the gas blend delivered to the tubing network. The separate gas flows are controlled by servo-actuated flow control valves actuated by a control gas pressure which is applied or released in response to such backpressure.

Abstract: An arming fuze for ordnance type munitions having but one movable part comprising a solvent desensitized liquid explosive contained in a ported (ventilated) cavity that is normally sealed by a sleeve. Upon movement of the sleeve and exposure of the liquid explosive within the cavity to the air, the liquid explosive loses a volatile solvent, the desensitizing agent, and becomes progressively more sensitive. A first embodiment is that of an inertia armed nose fuze for a projectile wherein the desensitized liquid explosive is enclosed in the cavity in a porous solid matrix. Upon rapid acceleration, as when the projectile is fired, the sleeve undergoes set-back thereby exposing the porous matrix to a violent slip stream of air and to a strong desiccating action. The liquid explosive rapidly loses solvent to the air, rapidly becoming more sensitive whereby it is impact sensitive by the time impact on the target occurs.

Abstract: A system for sensing the angular position of a code ring of magnetic matel which is rotatable about a cylindrical housing, also magnetic material, to any one of a predetermined number of code ring settings. Either or both the cylindrical housing and the code ring include permanent magnets to provide a magnetic circuit including both of these elements. The code ring has an inner surface which carries an N-bit digital code of magnetic material in N tracks. N Hall effect digital switches are disposed on the cylindrical housing adjacent the N tracks of digital code bits, respectively. Each Hall effect digital switch senses whether a code bit is adjacent to it. The Hall effect digital switches are read by associated electronics within the housing to provide a digital signal indicating the code ring setting.

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.