GB2022222A - Electric ignition of explosives - Google Patents

Abstract

In an ignition system for the firing of a plurality of electrically actuable igniters (16), the ignition leading wire (17) of each igniter is formed from a continuous length of insulated wire connecting its two electrical connection terminals. The leading wire is looped around a transformer core (14) having a movable portion (15) that is opened to admit the loop. A firing cable (12) coupled to a source of electrical firing energy (11) is also looped around the transformer. A plurality of transformer cores can be coupled to a single firing energy source by looping a continuous wire from the source, through each transformer and then back to the source. In an alternate configuration, the igniter leading wires (17) are each loop coupled to a toroidal core which is in turn electromagnetically coupled to a transformer by a single loop of insulated wire looped through the core of the transformer and each toroidal core. The ignition system avoids the need to make wire-to-wire connections in detonator assemblies and the external detonator leading wires may be fully insulated at all times. <IMAGE>