Classifications

• • C—CHEMISTRY; METALLURGY
  • C06—EXPLOSIVES; MATCHES
  • C06B—EXPLOSIVES OR THERMIC COMPOSITIONS; MANUFACTURE THEREOF; USE OF SINGLE SUBSTANCES AS EXPLOSIVES
  • C06B23/00—Compositions characterised by non-explosive or non-thermic constituents
  • C06B23/001—Fillers, gelling and thickening agents (e.g. fibres), absorbents for nitroglycerine
• • C—CHEMISTRY; METALLURGY
  • C06—EXPLOSIVES; MATCHES
  • C06B—EXPLOSIVES OR THERMIC COMPOSITIONS; MANUFACTURE THEREOF; USE OF SINGLE SUBSTANCES AS EXPLOSIVES
  • C06B29/00—Compositions containing an inorganic oxygen-halogen salt, e.g. chlorate, perchlorate
• • C—CHEMISTRY; METALLURGY
  • C06—EXPLOSIVES; MATCHES
  • C06C—DETONATING OR PRIMING DEVICES; FUSES; CHEMICAL LIGHTERS; PYROPHORIC COMPOSITIONS
  • C06C9/00—Chemical contact igniters; Chemical lighters

Definitions

• the invention relates to a thermally sensitive pyrotechnic early ignition set according to the preamble of claim 1.
• the explosive usually an efficient pyrotechnic gas set - burns in defined milliseconds when triggered and briefly inflates an impact bag or tightens the belt by triggering a retractor.
• the gas sets are housed in stable housings made of aluminum or steel. When triggered, the gas formed is freed of entrained particles by filter material and blown out through openings in the housing.
• the gas charge or sets are usually triggered by rapid pyrotechnic, electrically triggered Lighters that convert in less than 2 milliseconds and ignite the gas-generating mixture and bring it to sales, either alone or reinforced by a booster (another explosive component of airbags).
• the nature of these electrically triggered ignition charges are thermally stable mixtures. They are designed to be chemically and mechanically very stable because the test criteria for airbags and belt tensioners require a corresponding robustness, which must be maintained during the life of the vehicle, which is up to 15 years.
• thermally sensitive, pyrotechnic early ignition kits are introduced into the gas generators, which trigger airbags and belt tensioners before the dangerous situation described can occur.
• good thermal conductivity Place e.g. directly in the electric igniter of the airbag or belt tensioner itself or on the housing of the gas generator, an early ignition kit is attached, which is triggered in a vehicle fire by the heat transferred to metal parts, e.g. via the metal of the igniter cap or the gas generator housing, at temperatures around 180 ° C and, in turn, safely ignites the actual priming charge or the priming amplifier set (booster) or directly the gas set.
• boost priming amplifier set
• Such a pyrotechnic early ignition set which triggers by heating to temperatures of around 180 ° C., is not without problems in terms of safety.
• the relatively low temperature requires very reactive components with low activation energy.
• this mixture must withstand the demanding safety-related test conditions of igniters in the automotive sector without damage.
• a temperature resistance which has to be verified with a test for 400 h at a temperature of approx. 110 ° C or briefly 12 h at 125 ° C, the mechanical strength and adhesion of the early ignition set on the igniter or gas generator housing are particularly noteworthy.
• WO 95/26945 describes an early ignition charge with an oxidizing agent based on alkali or alkaline earth metal chlorates and a fuel Carbohydrates are known, these components being mixed wet in the presence of water, ethyl alcohol or mixtures thereof and this moist composition is then dried. This early ignition set is then introduced directly into the housing of the ignition set.
• the structural strength of the early ignition set according to the prior art is usually increased by increasing the density, e.g. by pressing the sentence, improved.
• the problems mentioned can also occur here.
• the invention has for its object to provide a thermally sensitive early ignition charge based on chlorates and carbohydrates, which optimally fulfills the safety criteria described.
• Fiber material is thus added to the batch dispersion or the pasty batch of the early ignition batch.
• Fiber material such as glass, ceramic, carbon pulp, cotton or textile fibers increase the structural strength of the early ignition set significantly and guarantee a high resistance to stress cracks and aging-related detachment of the early ignition set.
• Fiber lengths of 0.05 to 10 mm, preferably 0.1 to 1 mm with diameters of 0.001 to 0.05 mm, preferably to 0.01 mm, are preferably used.
• the length of the fibers essentially depends on the type of base or holder for the early ignition set. If, for example, the early ignition set is applied directly to a wall of the gas generator or on an ignition board, longer fibers are required; if the early ignition kit is inserted directly into the ignition kit housing, short fibers are used.
• the fibers can have a roughened surface; Fibrillated fibers are also very suitable.
• This mixture is pasted with a solvent which contains the binder in solution while the other components are dispersed therein, in the above example iso-propanol is suitable.
• the solvent-moist mixture After the solvent-moist mixture has been dripped or spread onto the support base, the solvent is removed by tempering and / or vacuum.
• the binder and the fiber material ensure that the early ignition charge remains as a structurally stable mass that resists vibrations and thermal shock loads. It is not necessary to press the set.
• potassium chlorate In addition to potassium chlorate, other alkali metal and alkaline earth metal chlorates or mixtures thereof can be used as chlorate, and other carbon-rich organic compounds in addition to sucrose as carbohydrate.
• Glass, ceramic or carbon fibers or cellulose, cotton or textile plastic fibers can be used as the fiber material.
• Suitable binders are polyvinyl pyrrolidone, polyvinyl butyral, polyvinyl alcohol, ethyl cellulose, hydroxypropyl cellulose or polytetrafluoroethylene.
• the early ignition charge is preferably brought to the desired site of action as a paste, as a dispersion or by extrusion.

Landscapes

• Chemical & Material Sciences (AREA)
• Organic Chemistry (AREA)
• Inorganic Chemistry (AREA)
• Chemical Kinetics & Catalysis (AREA)
• General Chemical & Material Sciences (AREA)
• Air Bags (AREA)

Applications Claiming Priority (2)

Publications (2)

Family

ID=7692760

Family Applications (1)

Country Status (2)

Cited By (2)

Families Citing this family (1)

Citations (1)

Family Cites Families (5)

• 2001
  • 2001-07-23 DE DE2001135774 patent/DE10135774A1/de not_active Withdrawn
• 2002
  • 2002-07-18 EP EP02016033A patent/EP1279654A3/fr not_active Withdrawn

Patent Citations (1)

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