# US 5,347,931 A · Combustible flare ignition system > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 5,347,931 A - Document ID: US5347931A - Status: Granted - Kind: A - Application number: 07/974,746 - Filed: 1992-11-12 - Granted: 1994-09-20 - Earliest claimed: 1992-11-12 - Assignees: Thiokol Corporation - Inventors: Evan E. Day - Web page: https://patentgrep.com/patent/US5347931A ## CPC - F42B 12/42: of illuminating type, e.g. carrying flares - F42B: EXPLOSIVE CHARGES, e.g. FOR BLASTING, FIREWORKS, AMMUNITION (explosive compositions C06B; fuzes F42C; blasting F42D) ## Abstract A combustible ignition system for use in an illuminating flare warhead. The ignition system includes a pickup charge positioned contiguous the separation charge of the ignition initiator. The pickup charge is positioned such that the firing of the separation charge triggers combustion of the pickup charge. The pickup charge extends to a combustible train which comprises a continuous thin-layer explosive composition positioned within a plastic tubing. The firing of the pickup charge creates sufficient shock that the combustible train is detonated. The combustible train extends along the flare casing adjacent the parachute system and the illuminant. At the head end of the warhead, the explosive train connects to an output charge. The explosive shock of the explosive train is sufficient to detonate the output charge. The output charge transfers the combustion to a BKNO.sub.3 pellet basket within the illuminant igniter of the warhead. Ignition of the pellet basket ignites a propellant wafer which generates sufficient heat to ignite the illuminating composition of the flare. ## Claims ### Claim 1 An ignition system for an illuminant containing warhead, comprising: an ignition initiator; a combustible train, comprising a material which is shock sensitive and which is not heat sensitive, in communication with said ignition initiator such that the firing of said ignition initiator triggers combustion of said combustible train; and an illuminant igniter positioned in communication with said combustible train such that the firing of said combustible train triggers the firing of said illuminant igniter, thereby permitting the illuminant to be ignited, the illuminant igniter configured such that inadvertent firing of the illuminant igniter will not trigger combustion of the combustible train. ### Claim 2 (depends on 1) An ignition system as defined in claim 1, wherein said combustible train comprises a continuous pyrotechnic composition. ### Claim 3 (depends on 1) An ignition system as defined in claim 1, further comprising an output charge positioned contiguous said combustible train such that the firing of said combustible train triggers combustion of said output charge, said output charge configured such that the firing of said output charge triggers the firing of said illuminant igniter. ### Claim 4 (depends on 3) An ignition system as defined in claim 3, wherein said output charge and said combustible train are selected such that the firing of said output charge will not trigger combustion of said combustible train. ### Claim 5 (depends on 1) An ignition system as defined in claim 1, wherein said combustible train comprises a continuous combustible composition positioned within a meltable tubing. ### Claim 6 (depends on 5) An ignition system as defined in claim 5, wherein said ignition initiator and said meltable tubing are selected such that if said ignition initiator may be ignited by heat, the ignition temperature of said ignition initiator is greater than the melting temperature of said meltable tubing, such that exposure of the warhead to continuously increasing temperatures will result in said meltable tubing melting and destroying the continuity of said continuous combustible composition before said ignition initiator ignites. ### Claim 7 (depends on 5) An ignition system as defined in claim 5, wherein said illuminant igniter and said meltable tubing are selected such that if said illuminant igniter may be ignited by heat, the ignition temperature of said illuminant igniter is greater than the melting temperature of said meltable tubing, such that exposure of the warhead to continuously increasing temperatures will result in said meltable tubing melting and destroying the continuity of said continuous combustible composition before said illuminant igniter ignites. ### Claim 8 (depends on 1) An ignition system as defined in claim 1, wherein the warhead is attached to a propulsion device, and wherein said ignition initiator comprises a separation charge for promoting the separation of the propulsion device from the illuminant containing warhead. ### Claim 9 (depends on 8) An ignition system as defined in claim 8, wherein said ignition initiator further comprises a pickup charge positioned in communication with said separation charge such that the firing of said separation charge triggers combustion of said pickup charge, said pickup charge positioned contiguous to said combustible train such that the firing of said pickup charge triggers combustion of said combustible train. ### Claim 10 (depends on 8) An ignition system as defined in claim 8, wherein said ignition initiator comprises a fuse positioned in communication with said separation charge such that the firing of said fuse triggers combustion of said separation charge. ### Claim 11 (depends on 10) An ignition system as defined in claim 10, wherein said fuse comprises a variable range fuse. ### Claim 12 A pyrotechnic ignition system for use in igniting illuminant in a warhead, the warhead attached to a propulsion device, comprising: an ignition initiator, comprising: a fuse; and a separation charge for promoting the separation of the propulsion device from the warhead, said separation charge positioned in communication with said fuse such that the firing of said fuse triggers combustion of said separation charge; a pyrotechnic train positioned in communication with said separation charge such that the firing of said separation charge triggers combustion of said pyrotechnic train, said pyrotechnic train comprising a continuous pyrotechnic composition which is shock sensitive and which is not heat sensitive; an output charge positioned contiguous said pyrotechnic train such that the firing of said pyrotechnic train triggers combustion of said output charge; and an illuminant igniter positioned in communication with said output charge such that the firing of said output charge triggers the firing of said illuminant igniter, thereby permitting the illuminant to be ignited, the illuminant igniter and output charge configured such that inadvertent firing of the illuminant igniter will not trigger combustion of the combustible train. ### Claim 13 (depends on 12) A pyrotechnic ignition system as defined in claim 12, wherein said fuse comprises a variable range fuse. ### Claim 14 (depends on 12) A pyrotechnic ignition system as defined in claim 12, further comprising a pickup charge positioned in communication with said separation charge such that the firing of said separation charge triggers combustion of said pickup charge, said pickup charge positioned contiguous to said pyrotechnic train such that the firing of said pickup charge triggers combustion of said pyrotechnic train. ### Claim 15 (depends on 12) A pyrotechnic ignition system as defined in claim 12, wherein said output charge comprises a shock-sensitive combustible composition. ### Claim 16 (depends on 12) A pyrotechnic ignition system as defined in claim 12, wherein said continuous pyrotechnic composition is positioned within a plastic tubing. ### Claim 17 (depends on 16) A pyrotechnic ignition system as defined in claim 16, wherein said plastic tubing comprises polyethylene tubing. ### Claim 18 (depends on 16) A pyrotechnic ignition system as defined in claim 16, wherein said ignition initiator and said plastic tubing are selected such that if said ignition initiator may be ignited by heat, the ignition temperature of said ignition initiator is greater than the melting temperature of said plastic tubing, such that exposure of the warhead to continuously increasing temperatures will result in said plastic tubing melting and destroying the continuity of said continuous pyrotechnic composition before said ignition initiator ignites. ### Claim 19 (depends on 18) A pyrotechnic ignition system as defined in claim 18, wherein said plastic tubing has a melting temperature less than about 240.degree. F. and said separation charge is heat sensitive and has an ignition temperature of at least about 270.degree. F. ### Claim 20 (depends on 16) A pyrotechnic ignition system as defined in claim 16, wherein said illuminant igniter and said plastic tubing are selected such that if said illuminant igniter may be ignited by heat, the ignition temperature of said illuminant igniter is greater than the melting temperature of said plastic tubing, such that exposure of the warhead to continuously increasing temperatures will result in said plastic tubing melting and destroying the continuity of said continuous pyrotechnic composition before said illuminant igniter ignites. ### Claim 21 (depends on 20) A pyrotechnic ignition system as defined in claim 20, wherein said plastic tubing has a melting temperature less than about 240.degree. F. and aid illuminant igniter comprises a heat-sensitive combustible composition having an ignition temperature of at least about 350.degree. F. ### Claim 22 An insensitive pyrotechnic ignition system for use with a variable range, illuminant containing warhead, the warhead attached to a propulsion device, comprising: a variable range fuse; a separation charge for promoting the separation of a propulsion device from the warhead, said separation charge positioned in communication with said fuse such that the firing of said fuse ignites said separation charge; a pickup charge positioned in communication with said separation charge such that the firing of said separation charge triggers combustion of said pickup charge; a pyrotechnic train positioned contiguous to said pickup charge such that the firing of said pickup charge triggers combustion of said pyrotechnic train, said pyrotechnic train comprising a continuous pyrotechnic composition positioned within a plastic tubing, said plastic tubing selected such that the melting temperature of said plastic tubing is less than the ignition temperature of said separation charge and of said pickup charge, such that exposure of the warhead to continuously increasing temperatures will result in said plastic tubing melting and destroying the continuity of said continuous pyrotechnic composition before either of said separation charge and said pickup charge ignites; an output charge positioned contiguous said pyrotechnic train such that the firing of said pyrotechnic train triggers combustion of said output charge, said output charge selected such that the firing of said output charge will not trigger combustion of said pyrotechnic train; and an illuminant igniter positioned in communication with said output charge such that the firing of said output charge triggers the firing of said illuminant igniter, thereby permitting the illuminant to be ignited. ### Claim 23 (depends on 22) An insensitive pyrotechnic ignition system as defined in claim 22, wherein said continuous pyrotechnic composition is not heat sensitive. ### Claim 24 (depends on 23) An insensitive pyrotechnic ignition system as defined in claim 23, wherein said continuous pyrotechnic composition comprises a shock-sensitive explosive composition having a combustion velocity greater than about 5,000 ft/sec. ### Claim 25 (depends on 22) An insensitive pyrotechnic ignition system as defined in claim 22, wherein said plastic tubing has a melting temperature less than about 240.degree. F. and said illuminant igniter comprises a heat-sensitive combustible composition having an ignition temperature of at least about 350.degree. F. ### Claim 26 (depends on 25) An insensitive pyrotechnic ignition system as defined in claim 25, wherein said output charge comprises a shock-sensitive combustible composition and said continuous pyrotechnic composition comprises a shock-sensitive and shock-generating composition. ### Claim 27 (depends on 25) An insensitive pyrotechnic ignition system as defined in claim 25, wherein said pickup charge comprises a shock-sensitive combustible composition and said continuous pyrotechnic composition comprises a shock-sensitive and shock-generating composition. ### Claim 28 An ignition system for an illuminant containing warhead attached to a propulsion device, comprising: an ignition initiator comprising a separation charge for promoting the separation of the propulsion device from the illuminant containing warhead, and a variable range fuse positioned in communication with the separation charge such that the firing of the fuse triggers combustion of the separation charge; a combustible train positioned in communication with the ignition initiator such that the firing of the ignition initiator triggers combustion of the combustible train; and an illuminant igniter positioned in communication with the combustible train such that the firing of the combustible train triggers the firing of the illuminant igniter, thereby permitting the illuminant to be ignited. ### Claim 29 An ignition system for an illuminant containing warhead, the warhead attached to a propulsion device, comprising: an ignition initiator comprising a separation charge for promoting the separation of the propulsion device from the illuminant containing warhead, and a pickup charge positioned in communication with the separation charge such that the firing of the separation charge triggers combustion of the pickup charge; a combustible train positioned contiguous to the pickup charge such that the firing of the pickup charge triggers combustion of the combustible train; and an illuminant igniter positioned in communication with the combustible train such that the firing of the combustible train triggers the firing of the illuminant igniter, thereby permitting the illuminant to be ignited. ### Claim 30 An ignition system for an illuminant containing warhead, comprising: an ignition initiator; a combustible train positioned in communication with the ignition initiator such that the firing of the ignition initiator triggers combustion of the combustible train, the combustible train comprising a continuous combustible composition positioned within a meltable tubing; and an illuminant igniter positioned in communication with the combustible train such that the firing of the combustible train triggers the firing of the illuminant igniter, thereby permitting the illuminant to be ignited. ### Claim 31 (depends on 30) An ignition system as defined in claim 30, wherein said ignition initiator and said meltable tubing are selected such that if said ignition initiator may be ignited by heat, the ignition temperature of said ignition initiator is greater than the melting temperature of said meltable tubing, such that exposure of the warhead to continuously increasing temperatures will result in said meltable tubing melting and destroying the continuity of said continuous combustible composition before said ignition initiator ignites. ### Claim 32 (depends on 30) An ignition system as defined in claim 30, wherein said illuminant igniter and said meltable tubing are selected such that if said illuminant igniter may be ignited by heat, the ignition temperature of said illuminant igniter is greater than the melting temperature of said meltable tubing, such that exposure of the warhead to continuously increasing temperatures will result in said meltable tubing melting and destroying the continuity of said continuous combustible composition before said illuminant igniter ignites.