GB863477A - Improvements in pyrotechnic devices, and electrical dischargers for use therewith - Google Patents

Abstract

863,477. Pyrotechnic devices. SHERMULY PISTOL ROCKET APPARATUS Ltd. Nov. 26,1959 [Nov. 27, 1958], No. 38270/58. Class 9(2). A pyrotechnic device 1 comprises a tubular casing 3 of electrically conductive light alloy, an explosive charge 10, a plug 5 of electrically insulating synthetic resin and an electrical contact ring 6 of light alloy mounted on the plug and axially spaced from the end of the casing. The outer surface of the casing is coated with a layer 22 of electrically insulating material e.g. stove enamelling, except for a band 23, which forms the second electrical contact of the device. Each contact 6, 23, is respectively aligned with a member 25 of the discharge tube, Fig. 2 (not shown), prior to discharge. An electrical igniter 13, adjacent a delay fuze 12, is connected between the casing and the contact ring 6 by leads 16 and 14 respectively. Circumferential grooves 4 and 7 in the plug 5 secure the ends of the casing and contact ring respectively and the shoulder 8 of the plug ensures electrical insulation between them. A synthetic resin closing cap 20, with a pressure relieving aperture 21 therethrough, is screwed into the plug, and a parachute flare 2 is contained in the casing by a removable closure 18. In operation, a sufficient voltsage is applied across the contact 6, 23 to fire the igniter 13 which burns the delay fuze 12 and so the charge 10, which initiates the fuze (not shown) of the flare 2 and also ejects the flare by removing the closure 18. An openended discharger, as in Specification 863,476, is used.