Imperial Chemical Industries Limited

Orica Explosives Technology Pty Limited

Ici Canada, Inc.

Orica International Pte Ltd

Sek Kwan Chan

Graeme Allan Leiper

Steven J Graham

Ian John Kirby

George Gary Kelly

Joseph Georges Mario Lecompte

John Cooper

Ronald F Stewart

Howard A Bampfield

Raymond Oliver

Vladimir Sujansky

Raymond Carriere

Ray Oliver

John T Reid

Noel Yu Hsu

Moira Logan

A method of characterizing the structure of a void sensitized liquid energetic material, which method comprises defining the material in terms distribution function, the distribution function representing the fraction of liquid energetic material that occurs at a given point within the void sensitized liquid energetic material.

Method of characterising the structure of a void sensitized explosive composition

A wireless or partially wireless detonator assembly () and corresponding blasting apparatus, that may be 'powered Up' by a remote source of power () that is entirely distinct from the energy used for general command signal communications (). In one embodiment, the detonator assembly () may include an active power source () with sufficient power for communications, but insufficient power to cause intentional or inadvertent actuation of the detonator ().

Wireless detonator assemblies, corresponding blasting apparatuses, and methods of blasting

A connector block for retaining at least one shock tube in signal transfer relationship with a detonator. The connector block comprises a housing () having a bore () formed therein for receiving a detonator () provided with a percussion-actuation end (), a shock tube retention means () defining with the housing a slot () for receiving therein at least one shock tube () and holding the at least one shock tube in signal transfer relationship with the percussion-actuation end of the detonator present in the bore, the slot having an entrance () for allowing insertion of the at least one shock tube into the slot, and a flexible and resilient closure member () or an inflexible closure member () pivotable on a sprung hinge () extending partially or fully into the entrance. The closure member and the shock tube retention means resiliently flex to allow entry of the at least one shock tube through the entrance and into the slot, the closure member flexing through a distance at least 30% the diameter of the shock tube.

Connector block with shock tube retention means and flexible and resilient closure member

The present invention provides for a connector block for retaining at least one shock tube in signal transmission relationship with the percussion-actuation end of a detonator. The connector blocks of the present invention comprise a slot () for the retention of shock tubes therein, wherein the slot is configured to induce a bend () in the shock tube(s). In this way, the position of the shock tube(s) relative to the detonator is significantly improved. Air gaps between the shock tubes and the detonator, resulting from manufacturing tolerances, can be substantially eliminated. Moreover, the connector blocks of the present invention provide an increased security of shock tube retention, thereby reducing the risk of accidental shock tube removal or displacement.

Connector block configured to induce a bend in shock tubes retained therein

A detonator device and assembly for the initiating a plurality of signal transmission lines with a pressure impulse. The detonator device comprising a detonator casing having a signal receiving end and a firing end. The firing end of the detonator device being substantially shaped to conform with the pressure impulse initiation therein. The firing end having a contact wall of substantially uniform thickness for contacting a plurality of signal transmission lines in a compatible connector element and transmitting a pressure impulse thereto.

Blast initiation device

A process for the production of a gas-generating composition containing a redox-couple including a water soluble azide component, for example, azide of sodium, potassium, lithium, calcium or barium, and an oxidizer component, for example, sodium nitrate, sodium perchlorate, potassium nitrate, potassium perchlorate or an oxide of iron, nickel, vanadium, copper, titanium, manganese, zinc, tantalum, silicon or aluminium, said oxidizer component being capable of reacting with said azide component to generate gas, said process comprising the steps of: forming an aqueous dispersion of the redox-couple wherein the azide component is totally dissolved and the oxidizer is uniformly dispersed and stabilised in the azide solution; passing said aqueous dispersion through a spray nozzle to form a stream of droplets; and contacting said droplets with hot air whereby the water is removed to produce solid particles of gas-generating composition.

Process for the preparation of gas-generating compositions

The pyrotechnic ignition device of this invention comprises a hollow tubular coiled charge of pyrotechnic sheet material defining an ignition initiation position, the internal diameter of the charge decreasing and the wall thickness increasing over at least a portion of the charge extending from the initiation position in the direction of burning. This configuration enhances the reliability of ignition and the rate of flame development. Preferably the adjacent plies of the coiled charge are spaced apart. The preferred coiled charge also has a portion downstream from the initiation position in the direction of burning which decreases in external diameter and wall thickness in a direction extending away from the initiation position, the configuration of this portion being effective to enhance the speed and violence of burning of a main gas-generating propellant charge ignited by the coiled charge. In the preferred device a pyrotechnic sheet comprising a substrate of oxidizing polymeric film coated with an oxidizable metal, for example magnesium, is coiled around a cruciate axial former so that the end edges define helices. Conveniently the coiled charge may be formed by winding the sheet into a right cylindrical tubular coil and pushing out the coil axially from the centre in the direction of burning.

Pyrotechnic ignition device

The invention provides pyrotechnic sheet material comprising a substrate of porous, vapour-permeable oxidizing polymeric film, for example a halogenopolymeric film, having a layer of oxidizable material for example magnesium, on at least part of its surface, the substrate and the oxidizable material being conjointly capable of reacting together on ignition. Advantageously at least part of the oxidizing material is accommodated within the polymer pores. The pyrotechnic sheet material burns faster than material comprising solid polymeric film.

Pyrotechnic sheet material

Precipitation of fine azide core particles with in-situ coating with suspended tiny oxide particles, followed by concentration of the dilute suspension of these bodies to form a slurry with residual dissolved azide in the liquor, and finally converting the slurry in to solid aggregates of the pyrotechnic bodies by e.g. prilling whereby liquid phase evaporation releases dissolved azide causing the pyrotechnic bodies to be adhered together in to larger aggregates.

Method of producing pyrotechnic masses

A hybrid inflator for a gas bag safety restraint system for use in a motorized vehicle comprises a compressed supply of stored gas heated by means of a gasless pyrotechnic material in sheet form. The sheeted pyrotechnic material may advantageously be located within the compressed gas storage vessel in a thin container or in direct contact with the gas. The invention also includes a heating element for a hybrid inflator. The preferred pyrotechnic material comprises a substrate of an oxidizing polymeric material for example, polytetrafluoroethylene (PTFE), coated with an oxidizable material, for example magnesium, which is capable of reacting exothermally with the oxidizing polymeric material. The pyrotechnic sheet produces solid products in very fine particle form which gives improved energy transfer to the stored gas. The invention facilities simple, cheaper constructions of hybrid inflators.

Hybrid inflator

A vehicle occupant safety restraint gas generator is provided in which the ignition system for the propellant comprises a pyrotechnic layer (22), e.g. a reactive film, preferably comprising a substrate of oxidizing polymeric film such as polytetrafluoro-ethylene (PTFE) having at least a portion of its surface covered with a layer of oxidizable material, for example magnesium, which may be vapour-deposited on the surface. The propellant is preferably a propellant train (12, 14, 16, 18) which comprises a plurality of adjacent propellant grains such as toroidal discs which surround the pyrotechnic layer or are completeley encased thereby. The gas generator is simpler and more economical to manufacture, and has improved safety during use.

Growing community of inventors

Pierrefonds, Canada

Sek Kwan Chan