the following describes embodiments of self contained fire extinguisher systems and methods of making and using self contained fire extinguisher systems in accordance with the present disclosure . embodiments in accordance with the present disclosure are set forth in the following text to provide a thorough understanding and enabling description of a number of particular embodiments . numerous specific details of various embodiments are described below with reference to self contained fire extinguisher systems on military vehicles , but embodiments can be used with other military , commercial or civilian vehicles , including terrestrial vehicles , marine vessels and aircraft . embodiments of self contained fire extinguisher systems according to the present disclosure may also be used in static structures , e . g ., kitchens . in some instances , well - known structures or operations are not shown , or are not described in detail to avoid obscuring aspects of the inventive subject matter associated with the accompanying disclosure . a person skilled in the art will understand , however , that the invention may have additional embodiments , or that the invention may be practiced without one or more of the specific details of the embodiments as shown and described . fig1 a shows an embodiment of a linear temperature sensor cord 100 according to the present invention . the cord preferably includes a core 101 and a casing 102 . the core 101 is preferably a pyrotechnic blend of fuel and oxidizer powders with additives that result in a low auto - ignition temperature , for example , in a range of approximately 225 degrees fahrenheit to approximately 800 degrees fahrenheit . generally , the range of auto - ignition temperatures is approximately 275 degrees fahrenheit to approximately 680 degrees fahrenheit , and preferably approximately 340 degrees fahrenheit to approximately 400 degrees fahrenheit . test results have demonstrated that , in a typical diesel fuel fire and with the cord 100 spaced nominally 18 inches from the fuel , combustion of the cord 100 initiates in less than approximately 60 seconds . in addition to auto - igniting , the core 101 burns rapidly to provide a short response time , e . g ., combustion propagates rapidly along the length of the cord 100 . other embodiments according to the present disclosure may have cores 101 without additives . embodiments of the cord 100 according to the present disclosure may have other constructions . for example , the casing 102 may include the fuel or the oxidizer and the core 101 may include the oxidizer or the fuel , respectively . such a cord 100 may accordingly be consumed during combustion propagation . other embodiments may include a pyrotechnic fluid core 101 , e . g ., a liquid or gas , that may be disposed inside or applied , e . g ., sprayed , dipped , etc ., onto a casing 102 . other embodiments according to the present disclosure may have other cores , e . g ., a wick treated with a pyrotechnic fluid . fig1 b illustrates a method for manufacturing the linear temperature sensor cord 100 . the casing 102 preferably includes a metal tube into which the pyrotechnic blend for the core 101 is loaded . the metal tubes may then pass thru dies , rollers , or other swaging devices to elongate the tube and reduce the diameter of the cord 100 . the tube material and properties may be selected for optimum thermal conductivity and tensile strength . preferably , the diameter of the pyrotechnic core is selected for ensuring that combustion of the pyrotechnic core 101 propagates around bends formed in the cord 100 . the wall thickness may be pre - determined according to the swaging procedure . the walls of the casing 102 are preferably concentric with the longitudinal axis of the cord 100 and preferably have a consistent wall thickness . preferably , the linear temperature sensor cord 100 can be easily bent by hand or by conventional tube bending tools and techniques to conform to a selected contour or path without crimping the cord 100 . fig1 c - 1e show arrangements of the linear temperature sensor cord 100 including features for adjusting sensitivity of the cord 100 to ambient temperature . fig1 c shows the cord 100 including a flattened portion 110 , fig1 d shows the cord 100 including a portion 120 having a cross - shaped cross - section , and fig1 e shows the cord 100 including a coiled portion 130 . the flattened portion 110 , the cross - shaped portion 120 , the coiled portion 130 , and other arrangements may provide the cord 100 with increased temperature sensitivity by increasing the surface area and / or thinning the wall of the casing 102 . other embodiments according to the present disclosure may have casings 102 that include materials other than metal , e . g ., natural fibers , polymers or other materials through which an elevated ambient temperature may be conveyed to auto - ignite the pyrotechnic core 101 . the casing 102 may also include a hybrid composition , e . g ., metal fibers woven into a tubular cotton sleeve . other manufacturing methods , e . g ., extruding or weaving , may also be used for manufacturing the cord 100 . fig2 a and 2b show two embodiments according to the present disclosure for partially enclosing and protecting the linear temperature sensor cord 100 . in particular , it may be desirable to at least partially enclose the cord 100 to protect it from impact , abrasion or other damage in exposed areas and / or to shield the cord 100 in areas that do not require temperature sensing . the cord 100 can be inserted in a solid or perforated metal tube 202 or a non - metallic sheath 203 for protection . these protective coverings or shields may be implemented at intervals along the longitudinal axis of the cord 100 , thus leaving uncovered or exposed portions along the longitudinal axis of the cord 100 . portions of the cord 100 that are covered with the sheath 203 may have reduced temperature sensitivity relative to the uncovered portions . it would therefore be preferable for sheaths 203 to be located along non - sensing lengths of the cord 100 for providing , for example , added impact or abrasion protection . the uncovered portions are preferably positioned in locations where it is desirable for the cord 100 to sense elevated ambient temperatures due to a fire . the tube 202 may provide impact protection substantially without adversely affecting the sensitivity of the cord 100 . for example , the thermal conductivity and / or perforations of the tube 202 may minimize any impediment that the tube 202 may cause to the cord 100 for sensing elevated temperatures due to a fire . accordingly , the tube 202 and / or the sheath 203 may ruggedize or provide additional protection to portions of the cord 100 without compromising the sensitivity of other portions of the cord 100 . fig3 a - 3c show attaching devices for supporting the linear temperature sensor cord 100 . fig3 a shows a resilient metal clip support device 301 , fig3 b shows an elastically deformable elastomer support device 302 , and fig3 c shows a preformed or plastically deformable wire form support device 303 . the support devices 301 / 302 / 303 may support the cord relative to structures ( not shown ) in the temperature sensing areas . variants of these support devices may also be used to support covered portions of the cord 100 , e . g ., portions of the cord 100 covered by the tube 202 or the sheath 203 . fig4 a shows a cup 401 enclosing an end of the linear temperature sensor cord 100 , and fig4 b illustrates a method of assembling the cup 401 onto the cord 100 . preferably , the cup 401 includes a thin - walled metallic cup that is partially filled with additional pyrotechnic material 402 . the cup 401 preferably slides onto and seals the end of the cord 100 . the additional pyrotechnic material 402 may provide a booster to propagate the initiation signal across junctions or manifolds for networking plural cords 100 . the material for the cup 401 may the same or different from that of the casing 102 , and the additional pyrotechnic material 402 may be the same or different from that of the core 101 . friction , adhesive , mechanical devices , or other coupling techniques may be used to temporarily or substantially permanently secure the cup 401 to the casing 102 . fig4 c shows a network juncture 403 a for coupling together ends of two temperature sensor cords 100 . fig4 d is a cross - section view of a network manifold 403 b for coupling together ends of four temperature sensor cords 100 . embodiments according to the present disclosure may include network couplings for three , five or more cords 100 , and may include any geometry that is suitable for propagating combustion across two or more ends . fig5 a and 5b show two embodiments of a boost initiator 500 that may be coupled at an output end of the linear sensor temperature cord 100 . the boost initiator boosts the combustion output of the cord 100 to ( 1 ) ignite a propellant fire suppression medium ; ( 2 ) provide pressure to open a valve ; or ( 3 ) provide pressure to puncture a sealing disc . fig5 a shows a pyrotechnic charge 501 that is initiated by the cord 100 . the size and material for the pyrotechnic charge 501 may be tailored to produce a selected quantity of pressure and / or heat , which may directly ignite a propellant type fire suppression medium , operate a valve , or rupture a sealing disc . the material for the pyrotechnic charge 501 may be the same or different from that of the core 101 and / or the additional pyrotechnic material 402 . referring to the embodiment of the boost initiator 500 shown in fig5 b , an integral metallic bulkhead 502 may be placed between two thermally sensitive charges , e . g ., a donor charge 503 and a receptor charge 504 . the temperature of each charge is sufficient to transfer ignition across the bulkhead 502 without compromising the structural integrity of the bulkhead 502 . the size and material for the receptor charge 504 may be tailored to produce a selected quantity of pressure and / or heat 505 , which may directly ignite a propellant type fire suppression medium or operate a valve or rupture a sealing disc while maintaining a pressure seal across the bulkhead 502 . the material ( s ) for the donor and receptor charges 503 / 504 may be the same or different from that of the core 101 and / or the additional pyrotechnic material 402 . embodiments according to the present disclosure may include several options for a fire suppression medium and its source . fire suppression mediums may include , e . g ., dry chemicals , liquids or inert gases . the sources for dry chemical and liquid fire suppression mediums are typically pressure vessels . discharging these fire suppression mediums from pressure vessels typically includes opening a valve or rupturing a sealing disc . inert gas fire suppression mediums are typically combustion products of a propellant that is not stored under pressure . pressure from an inert gas fire suppression medium may be generated when the propellant is ignited and the resulting combustion produces a pressurized inert gas as the output . fig5 c - 5e show embodiments of initiators , actuators and valves including one of the boost initiators 500 . fig5 c shows an inert gas generator propellant 510 that is initiated by the pyrotechnic charge 501 . accordingly , an inert gas fire suppression medium is discharged via an outlet 512 , e . g ., a nozzle , in response to the propellant 510 being ignited or initiated by the pyrotechnic charge 501 , which is preferably initiated by the linear sensor temperature cord 100 in response to sensing an elevated temperature that causes auto - ignition of the core 101 . fig5 d shows an actuator for discharging a pressurized fire suppression medium 520 , e . g ., a liquid or dry chemical fire suppression medium . the fire suppression medium 520 is discharged in response to the output of a boost initiator 500 displacing a piston 522 , which causes a sealing disc 524 to rupture thus allowing the pressurized fire suppression medium 520 to discharge through an outlet 526 . the boost initiator 500 is initiated by the linear sensor temperature cord 100 in response to sensing an elevated temperature that causes auto - ignition of the core 101 . fig5 e shows a valve for discharging a pressurized fire suppression medium 530 . the fire suppression medium 530 is discharged in response to the output of a boost initiator 500 displacing a piston 532 relative to a valve body 534 . preferably , this causes a shear nipple 536 to be lopped off thus allowing the pressurized fire suppression medium 530 to be discharged through an outlet 538 . the boost initiator 500 is initiated by the linear sensor temperature cord 100 in response to sensing an elevated temperature that causes auto - ignition of the core 101 . embodiments according to the present disclosure may include other configurations and combinations of fire suppression medium sources , discharge controllers and boost initiators . for example , certain embodiments according to the present disclosure may eliminate the boost initiator if the output pressure and / or heat from the linear sensor temperature cord is sufficient to actuate the discharge controller . in lieu of an electrically operated system , auto - ignition of the core of the linear sensor temperature cord in response to sensing an elevated temperature causes the fire suppression medium to be discharged . also , a network of the linear sensor temperature cords can be provided with different end configurations depending on the type of fire suppression medium and its source . fig6 a - 6c schematically show examples of systems that include one or more of the linear temperature sensor cords 100 to initiate a propellant , puncture a disk , or activate a valve on one or more sources of the fire suppression mediums 510 / 520 / 530 . preferably , the linear temperature sensor cord ( s ) connect to one or more inert gas generators . the cord ( s ) 100 can interface with a boost initiator 500 or directly with an igniter of the inert gas generator for initiating the propellant 510 . a solid inert gas generator propellant 510 may be preferable because it does not need to be stored in a pressurized cylinder and there is no residual material to remove or clean up after an inert gas discharge . fig6 a shows six sources of one or more of the fire suppression mediums 510 / 520 / 530 . a plurality of the linear temperature sensor cords 100 ( eight are shown in fig6 a ) are coupled to sources or one another by network manifolds 403 b ( three are shown in fig6 a ). in one embodiment according to the present disclosure , four of the six sources may be disposed in corresponding wheel wells of a vehicle and the two additional sources may be disposed proximate to the vehicle &# 39 ; s running gear , e . g ., in the engine compartment , battery compartment , etc . core combustion is initiated when the ambient temperature exceeds the auto - ignition temperature of at least one of the cords . the networked cords and sources are accordingly initiated and the fire suppression medium ( s ) are discharged . fig6 b shows one embodiment according to the present disclosure for providing a fire suppression system in a crew compartment of a vehicle . at least one linear temperature sensor cord 100 ( seven are shown in fig6 b ) is coupled to at least one source ( six are shown in fig6 b ) of a fire suppression medium 510 / 520 / 530 . the sources are preferably disposed inside a generally enclosed crew compartment and linked by networked cords for initiating the sources if the internal temperature exceeds the auto - ignition temperature . additional networked cords ( two are shown in fig6 b ) may be used to also initiate the sources if a temperature external to the crew compartment exceeds the auto - ignition temperature . certain embodiments according to the present disclosure may include implementing both the fire suppression system for the physical components ( fig6 a ) and the fire suppression system for the crew compartment ( fig6 b ) onboard a single vehicle as independent systems . moreover , independent systems for additional compartments , e . g ., cargo holds , fuel tanks , ammunition lockers , etc ., may also be included on a single vehicle . an integrated fire suppression system for a single vehicle may include a network of linear temperature sensor cords that couple together all of the sources onboard the vehicle . fig6 c shows an embodiment according to the present disclosure including a single length of the linear temperature sensor cord 100 and a single source of a fire suppression medium 510 / 520 / 530 . the single length may include a plurality of individual cords coupled in series by junctions ( not shown ). the linear temperature sensor cord may extend to several locations in a single compartment and / or may include portions extending into different spaces of a vehicle . thermal insulators 600 disposed around portions of the cord 100 may provide impact protection and / or reduce sensitivity to elevated temperatures that are routinely anticipated , e . g ., proximate an engine exhaust , and therefore do not represent a fire . preferably , the single source may be dedicated to providing a fire suppression system at a particular location , e . g ., a vehicle &# 39 ; s driver seat , in response to threats of fire from multiple locations / spaces around the vehicle . one or more of these individual fire suppression systems may be used on a single vehicle , with or without a networked fire suppression system also being onboard the vehicle . fig7 a schematically shows an embodiment according to the present disclosure of a fire suppression system 700 for a vehicle including a manual initiator 701 that can activate initiation the system 700 at any time or temperature . the system 700 preferably includes a plurality of networked linear temperature sensor cords 100 ( only one is indicated in fig7 a ), a plurality of sources of a fire suppression medium 510 / 520 / 530 ( six sources including gas generator propellants 510 a - 510 f are shown in fig7 a ), and a plurality of manual initiators 701 ( four manual initiators 701 a - 701 d are shown in fig7 a ). the sources of the fire suppression medium 510 are preferably distributed for discharging in the engine compartment 510 a / 510 b and each of the wheel wells 510 c - 510 f . alternate or additional sources may also be positioned in other locations on the vehicle . the manual initiator 701 a is preferably located in the crew compartment of the vehicle , e . g ., within reach of the driver . alternate or additional manual initiators may be positioned around the exterior of the vehicle . for example , the manual initiator 701 b may be positioned on the vehicle exterior , e . g ., proximate an entrance to the crew compartment at the back of the vehicle , and / or manual initiators 701 c / 701 d may be positioned on the either of the vehicle &# 39 ; s exterior sides . fig7 b and 7c are perspective views of examples of the manual initiators 701 shown in fig7 a . fig7 b shows an embodiment according to the present disclosure that includes a pull handle 702 for initiating the cord 100 coupled to the manual initiator 701 and fig7 c shows an embodiment according to the present disclosure that includes a rotary handle 703 for initiating the cord 100 coupled to the manual initiator 701 . in the event of a fire that does not reach the auto - ignition temperature , the manual initiators 701 can be manually activated . the manual initiators 701 are preferably positioned in non - hazardous areas and coupled to the sources of fire suppression medium 510 / 520 / 530 with the linear temperature sensor cords 100 . an example of a manual initiator is part number 813633 - 3 manufactured by pacific scientific energetic materials co . ( hollister , calif .). a method for suppressing a fire will now be described . embodiments according to the present disclosure preferably include a linear temperature sensor cord 100 that , when exposed to a fire having a temperature that exceeds the auto - ignition temperature of the cord 100 , initiates combustion of the cord &# 39 ; s core 101 . this core combustion propagates along the cord 100 to a source of a fire suppression medium 510 / 520 / 530 that is preferably positioned in a location to discharge the fire suppression medium 510 / 520 / 530 to suppress the fire . core combustion may propagate in a network of the cords 100 to initiate or actuate one or more suppression medium sources . likewise , individual suppression medium sources may be activated or initiated in response to core combustion from one or more of the cords 100 . core combustion may provide adequate pressure and / or heat to activate or initiate the fire suppression medium source , or a boost initiator 500 may couple the cord 100 to the source for increasing the pressure and / or heat from the cord 100 , and thereby provide sufficient pressure and / or heat to activate or initiate the source . the fire suppression medium sources preferably include a propellant 510 that is initiated to produce a fire suppression medium , a pressurized fire suppression medium 520 that is released by rupturing a sealing disk , or a pressurized fire suppression medium 530 that is released by opening a valve . embodiments according to the present disclosure discharging the fire suppression medium 510 / 520 / 530 without an electrical signal . accordingly , a fire or damage that disrupts electric power or circuits will not in turn adversely affect the fire suppression performance of embodiments according to the present disclosure . a method of providing a fire suppression system onboard a vehicle will now be described . embodiments according to the present disclosure preferably include a linear temperature sensor cord 100 that is routed into or through compartments or other locations on the vehicle such as engine compartments , crew compartments , wheel wells , fuel tanks , cargo holds , etc . the cord 100 may include an end positioned in a compartment or may include a loop or segment disposed in a compartment . ends of the cord 100 are preferably enclosed by a cup 401 , coupled to a boost initiator 500 at a source of a fire suppression medium 510 / 520 / 530 , coupled directly to the source of the fire suppression medium 510 / 520 / 530 , coupled to one or more manual initiators 701 , or networked with one or more other cords 100 via a juncture 403 a or a manifold 403 b . portions of the cord ( s ) 100 may be shielded from impact or abrasion with or without an appreciable effect on the temperature sensitivity of the cord 100 . for example , one or more portions of a cord 100 may be cinctured by a tube 202 or a sheath 203 with minimal impact on the ability of the cord 100 , and / or an insulator 600 may make one or more portions of the cord 100 less sensitive to the ambient temperature . cords 100 may be bent or otherwise formed into shapes that follow a selected route and may be supported with respect to vehicle along that route by resilient clips , wires , etc . the route that the cord ( s ) follow may also extend on external surfaces of the vehicle . embodiments according to the present disclosure may also be applicable to other environments such as kitchens , warehouses , or any structure in which it is preferable to provide fire suppression capabilities during electrical power outages . embodiments according to the present disclosure may also be applicable anywhere electricity for a fire suppression system is not available . embodiments according to the present disclosure may provide an elongated fire sensor rather than a conventional sensor that is located at a specific position and coupled by wires to a discharge controller . in contrast to these conventional sensors , the entire length of the linear temperature sensor cord 100 may provide fire sensing capabilities in addition to transmitting a signal to discharge a fire suppression medium . embodiments according to the present disclosure may also be used to break an electrical circuit . for example , a fire in a particular space may be sensed by an embodiment of the cord according to the present disclosure . the cord may be disposed throughout the space rather than using a conventional sensor ( s ) disposed at discrete locations . in response to auto - igniting the cord , an embodiment of the boost initiator according to the present disclosure may cut electrical power to the space . from the foregoing , it will be appreciated that specific embodiments of the invention have been described herein for purposes of illustration , but that various modifications can be made without deviating from the spirit and scope of the invention . accordingly , the invention is not limited by the specific embodiments .
a self contained fire extinguisher system that does not need external power in order to sense or initiate a release of a fire suppression medium , includes components configured to utilize a linear sensor network that can be connected to at least one and / or different sources of fire suppression mediums . a linear temperature sensing cord can be routed over a large area not practical with individual sensors . the cord can also actuate several and different sources of fire suppression mediums to maximize the suppression of a fire .