JPH10182275A - Gas generator for air bag and air bag device provided with the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a gas generator capable of generating gas which is exhausted from a gas exhaust port of the generator and contains a lesse amount of combustion residues, at the time of combusting a gas generating agent composition. SOLUTION: This gas generator is provided with a gas generating agent 6, a housing 3 that is used for receiving the gas generating agent 6 and has a gas exhaust port 11, a gas ignition means 4 for igniting the gas generating agent 6 and a filter 7 for filtering off combustion residues of the gas generating agent 6, wherein: the combustion residues in a filtered product gas exhausted from the gas exhaust port 11 is <=2g; an azide-based gas generating agent is used as the gas generating agent 6; and the bulk density of the filter 7 is 3.0 to 5.0g/cm<3> .

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an airbag apparatus for protecting a human body mounted on an automobile, an airplane, or the like. The present invention relates to a gas generator for an airbag in which combustion residues in gas are reduced.

[0002]

2. Description of the Related Art In a gas generator for an air bag used in an air bag system of an automobile or an aircraft at present, sodium azide is used as a gas generating agent (hereinafter referred to as an inorganic azide-based gas generating agent). Widely used. However, this inorganic azide-based gas generating agent reacts with heavy metals during its combustion to produce an explosive compound (combustion residue), so that the gas generated by the combustion of the gas generating agent contains combustion residues, It is considered that the airbag is damaged by the combustion residue.

[0003] In many cases, this combustion residue is filtered by a filter in a gas generator and the like, and is devised so as not to be ejected to an airbag as much as possible. However, when the bulk density of the filter is simply increased. Is not preferable because it causes an obstacle when the generated gas is ejected.

On the other hand, a gas generator using a nitrogen compound instead of sodium azide as a gas generating agent has been studied in order to avoid the generation of combustion residues due to the reaction with heavy metals during the combustion of the gas generating agent. As a nitrogen compound replacing sodium azide, for example, Japanese Patent Publication No. 57629/1994 discloses a gas generating composition containing a transition metal complex of tetrazole and triazole. In addition, Japanese Patent Application Laid-Open No.
No. 77 discloses a gas generating composition containing triaminoguanidine nitrate, and JP-A-6-239683 discloses a gas generating composition containing carbohydrazide.
No. 5 discloses a gas generant composition containing a nitrogen-containing nonmetal compound containing cellulose acetate and nitroguanidine. Furthermore, in USP 5,125,684, 15-30%
Discloses the use of nitroguanidine as an energetic material that coexists with the cellulosic binders. Also,
JP-A-4-265292 discloses a non-azide gas generant composition containing a high-temperature slag-forming substance or a low-temperature slag-forming substance.

[0005] However, when a nitrogen-containing organic compound is used in combustion, an oxidizing agent which generates only a chemical equivalent, that is, an amount of oxygen necessary for combustion of carbon, hydrogen and other elements in the compound molecule, is generally used. It has a drawback that the calorific value is large (that is, the combustion temperature is high) as compared with the azide compound. Thus, problems arising from high combustion temperatures include those erosion reactions that involve chemical reactions with stainless steel coolants or filters where the alkaline mist generated from the oxidizer component in the composition is commonly used. Accordingly, the high-temperature heat particles newly generated in the cooling unit are discharged out of the inflator and cause damage to the bag. However, if the alkaline mist generated from the oxidizing agent component and the newly generated high-temperature hot particles can be stopped in the combustion chamber by forming slag in the combustion chamber before reaching the cooling section, even if it is a high-temperature gas, Since the heat capacity of the gas is small, it is possible to establish a gas generator for an air bag that does not cause decisive damage to the bag using the filter.

[0006]

As described above, when the combustion gas is contained in the generated gas discharged from the discharge port of the gas generator for an air bag, the air bag is damaged, and the inherent performance of the air bag is damaged. May not be fully exerted. Therefore, an object of the present invention is to provide a gas generator for an airbag in which the generated residue discharged from a gas outlet when a gas generating agent burns is extremely small.

[0007]

Means for Solving the Problems The present inventors have conducted intensive studies to solve the above-mentioned problems, and as a result, have completed the present invention.

That is, the gas generator for an air bag according to the present invention comprises at least a gas generating agent, a housing containing the gas generating agent and having a gas outlet, and an ignition means for igniting the gas generating agent. In a pyrotechnic airbag gas generator comprising a filter for filtering combustion residue of a gas generating agent, the combustion residue in the generated gas discharged from the gas discharge port is 2 g or less. Things.

In a gas generator for a pyrotechnic airbag, the gas generated by its operation is exclusively due to the combustion of a solid or liquid gas generating agent, and the gas generator does not use a pressurized gas as a gas generating source. It is. In the case of a gas generator that uses pressurized gas as a gas generation source, even if a solid gas generating agent is used, the amount used is small, so the amount of combustion residue generated by combustion is also small. It is needless to say that substantially the same effect can be obtained according to the present invention.

The gas generator for a pyrotechnic airbag to which the present invention is applied generally has a housing having a diffuser shell having an opening for discharging gas (hereinafter referred to as a gas discharge port). And a closure shell having a central hole for installing or disposing the ignition means or the central cylinder member, respectively, by casting or press molding, and welding them together by various welding methods such as plasma welding. The diffuser shell and the closure shell are, for example, using a stainless steel plate having a thickness of 1.2 to 2.0 mm or 1.2 to 3.0 mm, respectively, and setting the outer diameter of the diffuser shell to 65 to 70 mm.
Or 45-75mm, the outer diameter of the closure shell is 65-75mm or
It can be formed as 45-75 mm. Instead of a stainless steel plate, a steel plate plated with nickel may be used. The housing is provided with a mounting flange. The total height of the housing is preferably 30 to 35 mm or 25 to 40 mm.

In the housing, a gas generating agent described in detail below is stored. The gas generating agent is ignited by the ignition means and burns to generate gas.

[0012] The generated gas generated by the combustion of the gas generating agent is then filtered by a filter disposed in the housing to remove combustion residues in the generated gas. It is preferable to form a gap of 1.0 to 4.0 mm that functions as a gas flow path between the outer peripheral wall of the housing and the filter. This filter can reduce a combustion residue contained in a normal gas generation amount generated by combustion of the gas generating agent at the time of operation of the gas generator to at least 2 g, preferably at least when a gas generating agent described in detail below is used. It must have a function of 1 g or less, particularly preferably 0.7 g or less. Here, the normal gas generation amount is naturally different depending on the application.For example, a gas generator for an airbag for a driver's seat of an automobile is 0.5 to 1.5.
mol for a gas generator for an airbag for the passenger seat. In the airbag gas generator of the present invention, regardless of the amount of generated gas,
The amount of combustion residue contained in the generated gas must be limited to the above-mentioned predetermined numerical value.

A filter having such a function can be realized, for example, by setting its bulk density to 3.0 to 5.0 g / cm ³ . For example, a filter having such a bulk density is formed by forming a stainless steel wire mesh into a cylindrical body and repeatedly bending one end of the cylindrical body outward to form an annular laminate, and compression-molding the laminate in a mold. Or, a stainless steel wire mesh is formed in a cylindrical body, and the cylindrical body is pressed in the radial direction to form a plate, and the plate is wrapped in a tubular shape to form a laminate, The laminate can also be formed by compression molding in a mold. The dimensions of this filter are, for example, 55-65 mm or 45
Outer diameter of ~ 65mm, inner diameter of 45 ~ 55mm or 30 ~ 55mm, and 26 ~
32mm or 19-37.6mm height.

The filter may have a wire diameter of 0.3 to 0.5 mm or a diameter of 0.3 to 0.5 mm.
It is also possible to use a double structure made of a wire mesh having a thickness of 3 to 0.6 mm and a layer having a thickness of 1.5 to 2.0 mm made of a wire mesh having a wire diameter of 0.5 to 0.6 mm inside.

The filter of the present invention is formed by laminating flat knitted metal meshes in the radial direction and compression-molding in the radial and axial directions. In the flat knitting, all the stitches are drawn out in one direction to form a loop, and this filter formed by laminating a wire mesh having such a stitch structure in the radial direction and compression molding has an excellent void structure, and is excellent. It has a trapping effect. Further, by having the predetermined wire diameter, and the predetermined bulk density,
The shape retention strength of the filter is significantly increased, so that deformation of the filter due to gas pressure is avoided, so that the normal function of trapping the combustion residue of the filter is ensured and the filter is made thinner.

Regarding the bulk density, preferably 3.5 to 4.5 g
/ Cm ³ .

As a material of the wire netting, for example, stainless steel can be used.
04, SUS310S, SUS316 (JIS standard symbol) and the like can be used. SUS304 (18
Cr-8Ni-0.06C) shows excellent corrosion resistance as an austenitic stainless steel.

A reinforcing ring having a large number of through-holes on the entire peripheral wall can be fitted to the outside and / or inside of the filter, but this is not always necessary. Instead of the reinforcing ring, a filter reinforcing member formed of an annular belt or the like can be used on the outer periphery of the filter means for the purpose of suppressing the expansion of the filter.

As the gas generating agent housed in the housing, a gas generating agent using an azide compound used in a conventional gas generator can be used, but preferably a non-azide nitrogen-containing organic compound is used. The non-azide gas generating agent used is used. This non-azide-based gas generating agent is composed of at least a nitrogen-containing organic compound, an oxidizing agent, and, if necessary, a slag forming agent. When the gas generating agent is formed into a molded article having a predetermined shape, a binder is blended. You can also.

Examples of the nitrogen-containing organic compound include one or more mixtures selected from the group consisting of triazole derivatives, tetrazole derivatives, guanidine derivatives, azodicarbonamide derivatives, and hydrazine derivatives.

As specific examples of these, 5-oxo-1,
2,4-triazole, tetrazole, 5-aminotetrazole, 5,5′-bi-1H-tetrazole, guanidine, nitroguanidine, cyanoguanidine, triaminoguanidine nitrate, guanidine nitrate, guanidine carbonate,
Biuret, azodicarbonamide, carbohydrazide, carbohydrazide nitrate complex, oxalic acid dihydrazide,
Hydrazine nitrate complex and the like can be mentioned. Among them, nitroguanidine and cyanoguanidine are preferable, and nitroguanidine is the most preferable compound because it has a small number of carbon atoms in the molecule. As nitroguanidine, there are low-density nitroguanidine in the form of needle crystals and high-density nitroguanidine in the form of bulk crystals, and any of them can be used.
The use of high density nitroguanidine is preferred.

The concentration of the compound varies depending on the number of carbon elements, hydrogen elements and other elements to be oxidized in the molecular formula, but is usually used in the range of 25 to 60% by weight, preferably 30 to 60% by weight.
It is used in the range of ~ 40% by weight. Although the absolute value differs depending on the type of the oxidizing agent used, if the amount is more than the theoretical amount of complete oxidation, the concentration of trace CO in the generated gas increases. . The range in which the optimum balance between the two is maintained is most preferable.

Various oxidizing agents can be used, and an oxidizing agent selected from at least one nitrate containing a cation selected from an alkali metal or an alkaline earth metal is used. Although the absolute value varies depending on the type and amount of the gas generating compound used, the amount is used in the range of 40 to 65% by weight, and particularly in relation to the CO and NOx concentrations described above.
A range of 45-60% by weight is preferred.

In addition, oxidizing agents such as nitrite and perchlorate, which are widely used in the field of airbag inflators, can also be used, but the number of oxygen in nitrite molecules is reduced as compared to nitrate, or the oxygen is released outside the bag. Nitrate is preferred from the viewpoint of, for example, reducing the generation of fine powder mist that is easily formed.

The function of the slag forming agent is to prevent the slag forming agent from being in a liquid state in order to avoid releasing, as a mist, an alkali metal or alkaline earth metal oxide generated by the decomposition of the oxidizing agent component, in particular, from the inflator. It is a function to change to a solid state and stop it in the combustion chamber, and it is possible to select a slag forming agent optimized by a difference in metal components.
Examples of the slag forming agent include naturally occurring clays containing aminosilicates such as bentonite and kaolin as main components, artificial clays such as synthetic mica, synthetic kaolinite and synthetic smectite, and hydrous magnesium silicate minerals. Such as talc, etc., and if necessary,
A slag forming agent selected from at least one of these can be used. Acid clay is a preferred slag forming agent.

For example, the viscosity and melting point of the oxide mixture in the ternary system of calcium oxide generated from calcium nitrate, aluminum oxide and silicon oxide as the main components in clay are in the range of 1350 ° C. to 1550 ° C. depending on the composition ratio. Changes the viscosity from 3.1 poise to about 1000 poise, and the melting point changes from 1350 ° C to 1450 ° C depending on the composition. By utilizing these properties, slag forming ability according to the mixture composition ratio of the gas generating composition can be exhibited.

The amount of the slag forming agent can be varied in the range of 1 to 20% by weight, but is preferably in the range of 3 to 7% by weight. If the amount is too large, the linear burning rate and the gas generation efficiency will decrease. If the amount is too small, the slag forming ability cannot be sufficiently exhibited.

A binder is a component necessary for obtaining a molded product of a desired gas generating composition, and exhibits a viscosity in the presence of water, a solvent, and the like, and does not significantly affect the combustion behavior of the composition. Any can be used. Examples of such a binder include metal salts of carboxymethyl cellulose, hydroxyethyl cellulose, cellulose acetate, cellulose propionate, cellulose acetate butyrate, nitrocellulose, and polysaccharide derivatives such as starch. And a water-soluble binder. A metal salt of carboxymethyl cellulose, particularly a sodium salt, is mentioned as the most preferred example.

The amount of the binder used can be in the range of 3 to 12% by weight, more preferably 4 to 12% by weight. The larger the amount, the stronger the fracture strength of the molded body.However, the larger the amount, the more the number of carbon elements and hydrogen elements in the composition increases, and a small amount of CO, which is an incomplete combustion product of carbon elements,
This is not preferable because the gas concentration increases and the quality of the generated gas deteriorates. Particularly, when the amount exceeds 12% by weight, the relative proportion of the oxidizing agent needs to be increased, and the relative proportion of the gas generating compound decreases, making it difficult to establish a practical inflator system.

Further, as a secondary effect of the sodium salt of carboxymethylcellulose, it is an oxidizing agent due to the presence of a molecular mixed microscopic state of sodium nitrate generated by a metal exchange reaction with nitrate during the production of a molded body using water. It has the effect of shifting the decomposition temperature of nitrates, especially strontium nitrate, which has a high decomposition temperature, to a lower temperature side and improving the combustibility.

Accordingly, the preferred gas generant compositions used in the practice of the present invention include: (a) about 25-60%, preferably 30-40%, by weight nitroguanidine; (b) about 40-65% by weight. %, Preferably 45-65% by weight oxidizing agent (c) about 1-20% by weight, preferably 3-7% by weight slag former (d) about 3-12% by weight, preferably 4-12% by weight A particularly preferred composition is (a) about 30 to 40% by weight of nitroguanidine (b) about 40 to 65% by weight of strontium nitrate (c) about 3 to 7% by weight A gas generant composition comprising, by weight, acid clay and (d) about 4 to 12% by weight of a sodium salt of carboxymethyl cellulose.

Thus, according to the present invention, (a) about 25-60% by weight nitroguanidine (b) about 40-65% by weight oxidizing agent (c) about 1-20% by weight slag former (D) An airbag gas generant molding comprising about 3 to 12% by weight of a binder is provided.

As a nitrogen-containing organic compound, dicyandiamide is also preferably used. The amount of the nitrogen-containing organic compound used in the gas generating composition varies depending on the number and molecular weight of the elements constituting the nitrogen-containing compound used, and the combination with the oxidizing agent and other additives. It is most preferable that the oxygen balance by the combination with the agent is near zero. However, by adjusting the oxygen balance to the positive side or the negative side in accordance with the above-mentioned concentration of the generated trace amounts of CO and NOx, an optimum molded molded product can be obtained. For example, when dicyandiamide is used, its amount is preferably in the range of 8 to 20% by weight.

As the oxidizing agent containing oxygen used in the present invention, an oxidizing agent known in the field of a gas generating agent for an air bag can be used, but basically, the residual component becomes a liquid or gas state, It is preferable to use an oxidizing agent having a property of generating a high melting point substance so as to reduce the thermal load on the coolant and the filter material.

For example, potassium nitrate is an oxidizing agent generally used as a gas generating agent, but a main residue component during combustion is potassium oxide or potassium carbonate, and potassium oxide is mixed with potassium peroxide at about 350 ° C. It decomposes into metallic potassium, and furthermore, potassium peroxide has a melting point of 763 ° C., and becomes a liquid or gas state when the gas generator is operated, which is not preferable in consideration of the thermal load on the coolant and the filter material.

The oxidizing agent preferably used in the present invention includes strontium nitrate. The main residue component of strontium nitrate during combustion is strontium oxide with a melting point of 2430 ° C., which is almost solid even when the gas generator is operating.

The amount of the oxidizing agent used in the present invention is not particularly limited as long as it is an amount of the oxidizing agent sufficient to completely burn the nitrogen-containing organic compound, and can be appropriately changed to control the linear burning rate and the calorific value. When strontium nitrate is used as an oxidizing agent for dicyandiamide, the content is preferably 11.5 to 55% by weight.

One of the preferred gas generating compositions of the present invention is 8 to 20% by weight of dicyandiamide, 11.5 to 55% by weight of strontium nitrate, and 24.5 to 80% of copper oxide.
% By weight of sodium salt of carboxymethylcellulose
The present invention contains 8 to 20% by weight of dicyandiamide, 11.5 to 55% by weight of strontium nitrate, 24.5 to 80% by weight of copper oxide,
Another object of the present invention is to provide a gas generant composition containing 0.5 to 8% by weight of a sodium salt of carboxymethyl cellulose.

Further, the present invention also provides an airbag device using the above-described gas generator for an airbag. This airbag device is formed by at least the gas generator, the impact sensor, and the airbag. In this airbag device, the gas generator operates in conjunction with the detection of the impact of the impact sensor to generate gas, and the generated gas is sent into the airbag, thereby protecting the occupant.

In this gas generator, the signal of the impact sensor may be sent to the control unit once, and the gas generator may be operated by the signal from the control unit. Can be housed in a module case and configured as a pad module, and can be mounted at appropriate places in the vehicle such as the steering wheel of the vehicle, the dashboard of the front passenger seat, and the back of the front passenger seat and the driver's seat.

[0041]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The gas generator for an air bag according to the present invention further comprises a partition having a through hole in the housing to define the interior of the housing into two or more chambers. The outside can be a gas generating agent combustion chamber. Then, a transfer charge and an igniter can be disposed in the ignition means storage chamber, and the gas generating agent can be stored in the gas generating agent combustion chamber. In this case, the flame due to the combustion of the transfer charge blows out from the through hole of the partition wall to ignite the gas generating agent.
This partition is integrally molded with the housing by casting,
It can also be formed by integrating a hollow cylindrical central cylindrical member made of a stainless steel plate or the like into the housing by welding or the like. Arrangement of a combustion ring outside the combustion chamber is optional in order to obtain optimum pressure conditions when the gas generating agent is burned in the combustion chamber.

Further, a filter supporting member can be arranged between the filter and the partition wall to prevent the movement of the filter. The filter support member may be formed of, for example, a stainless steel plate or a steel plate having a thickness of 0.5 to 1.0 mm, and may be disposed by the elasticity of the bent portions formed on the inner and outer peripheral portions. Further, the filter support member may be provided with a flameproof plate for protecting the inner peripheral surface of the filter from flame. Further, on the outer periphery and / or inner periphery of the filter member, a laminated metal net, a porous cylinder, an annular belt, a perforated basket, or the like may be provided for the purpose of suppressing the bulging.

The gas generator for an air bag according to the present invention further includes a gas generator according to the above-described embodiment, wherein the inside of the housing is not divided into two or more chambers by partition walls.
A chamber may be provided in which an igniter, a gas generating agent, a filter, and the like are provided.

[0044]

EXAMPLES The present invention will be specifically described below with reference to examples and comparative examples, but the present invention is not limited to only these examples.

[Gas Generator for Airbag] FIG. 1 is a sectional view of a gas generator for an airbag of the present invention. The gas generator includes a housing 3 composed of a diffuser shell 1 and a closure shell 2, a central cylindrical member 16 disposed in the housing 3 and serving as a partition, and an ignition means storage chamber 23 in the hollow portion of the central cylindrical member 16. Igniter 4 and the transfer agent 5, and a gas generating agent 6 described later, which is housed in the gas generating agent storage chamber 28 and is ignited by the flame of the transferring agent 5 to generate combustion gas. The filter member disposed around the gas generating agent 6, that is, the coolant filter 7, and the filter supporting members disposed at both ends of the coolant filter 7, that is, the plate members 32 and 33 Contains.

The coolant filter 7 has a wire diameter of 0.3
After forming a stainless steel mesh of 0.5 to 0.5 mm or 0.3 to 0.6 mm into a cylindrical body, one end of the cylindrical body is repeatedly bent outward to form an annular laminate, and the laminate is compression-molded in a mold. doing. The bulk density of this filter is 3.0-5.0
g / cm ³ . Pressure loss is 100L at normal temperature
/ Min / cm ² and 0.3 × 10 ^{-2 to} 1.5 × 10 ^-2 kg / cm ² . The coolant / filter 7 is formed by forming a stainless steel wire mesh into a cylindrical body, pressing the cylindrical body in the radial direction to form a plate, and winding the plate in multiple layers to form a laminate. The body can also be compression molded in a mold.

In FIG. 1, reference numeral 52 denotes a seal tape;
Reference numeral 4 denotes a holding member of the igniter, and reference numeral 29 denotes an outer layer made of a laminated metal net.

The gas generating agent 6 in this embodiment
Is a solid gas generating agent composed of nitroguanidine, Sr (NO ₃ ) ₂ , carboxymethylcellulose and acid clay, and its composition weight ratio is nitroguanidine: Sr (NO ₃ ) ₂ :
Carboxymethyl cellulose: acid clay = 35.4: 49.6:
10: 5. Nitroguanidine: Sr (NO ₃ ) ₂ : carboxymethylcellulose sodium salt: acid clay = 31.
5: 51.5: 10: 7 can also be used.

The gas generator for the air bag is operated with the gas generator accommodated in the tank to generate gas, the generated gas discharged from the gas generator is accommodated in the tank, and then the tank is washed with acetone. Thus, a combustion residue contained in the gas discharged from the gas discharge port 11 was obtained, and the amount of the combustion residue was measured.

As a result, the amount of the generated gas discharged from the outlet of the gas generator was 1 mol, and 0.3 g of the combustion residue was contained therein.

Next, a gas generator shown in FIG. 2 is another embodiment of the gas generator for an air bag according to the present invention. In this gas generator, a housing 63 composed of a diffuser shell 61 and a closure shell 62 is used. An igniter 64 disposed in a housing space in the housing 63; a solid gas generating agent 66 ignited by the igniter 64 to generate a combustion gas; and a gas generator housing the gas generating agent 66 And a coolant filter 67 defining a drug storage chamber 84. In FIG. 2, 77 indicates a through hole, 96 indicates a seal tape, and 91 indicates a filter support member. Also in this gas generator, when it is formed using the same gas generating agent 6 and coolant / filter 7 as the air bag gas generator shown in FIG. 1, the gas generator as shown in FIG. The same effect as the gas generator shown in FIG. 1 can be obtained.

Further, the gas generator shown in FIG. 3 is an example of a gas generator for an airbag suitable for being arranged on the passenger seat side. This gas generator has a plurality of gas generators arranged in a circumferential direction and an axial direction. A cylindrical portion 101 having a plurality of gas outlets 100;
Side wall portions 102 provided at both ends of the cylindrical portion 101
, And 103. A heat transfer tube 105 is disposed at the center of the housing 104. A large number of disk-shaped gas generating agents 106 are fitted on the outer surface of the heat transfer tube 105, and a coolant / filter is surrounded by these. 107 is provided. The transfer charge 108 and the igniter 10
9 is provided, and the ignition means is housed in the transfer tube 105. The other side wall 103
The fixing screw bolt 110 is fixed to the. The transfer tube 105 has an opening 1 through which the flame of the transfer charge 108 gushes out.
11 are provided, and these openings 111 are uniformly distributed and formed in the tube wall of the heat transfer tube. Housing 104
An aluminum tape 124 is fixed on the inner surface of the inner surface of the substrate in a region where the outlet 100 is formed for moisture prevention. In the operation of the gas generator, when an impact is detected by the sensor, a signal is sent to the igniter 109 to activate the igniter 109, thereby igniting the transfer charge 108 and generating a high-temperature flame. This flame is ejected from the opening 111 of the transfer tube 105. The blasted flame is the gas generating agent 10 in the open area.
Ignite 6. Thereby, the gas generating agent 106 burns to generate high-pressure combustion gas. This combustion gas passes through the entire area of the coolant filter 107, during which it is effectively cooled and the combustion residue is collected, and the cooled and purified combustion gas passes through the gas passage (gap 125) and passes through the aluminum passage. The tape breaks the wall of the tape 124 and is ejected from the gas outlet 100 and flows into an airbag (not shown). This inflates the airbag and forms a cushion between the occupant and the rigid structure to protect the occupant from impact.

The gas generator for an air bag suitable for being arranged on the passenger side as shown in FIG. 3 discharges 4 mol of gas, and the combustion residue contained therein is 0.6 g.

The gas generator for an airbag shown in FIG. 5 is a gas generator for an airbag suitable for being disposed on the passenger side, similarly to the gas generator shown in FIG. I have. That is, the housing 301 of the gas generator shown in FIG.
The annular end 332 of the cup-shaped member 303 formed in a substantially cup shape is inserted into the 323, and the two are welded and integrated. 5, reference numeral 306 denotes a punching plate, and the same members as those in FIG. Also in the gas generator shown in FIG. 5, the combustion residue contained in the exhaust gas is regulated to 2 g or less.

[Air Bag Apparatus] FIG. 4 shows an example of an air bag apparatus having the gas generator of the present invention. The airbag device includes a gas generator 80, an impact sensor 81, a control unit 82, a module case 83,
The air bag 84 is provided.

As the gas generator 80, the gas generator described with reference to FIG. 1 is used.

The impact sensor 81 can be composed of, for example, a semiconductor acceleration sensor. In this semiconductor type acceleration sensor, four semiconductor strain gauges are formed on a beam of a silicon substrate which is deflected when acceleration is applied,
These semiconductor strain gauges are bridge-connected.
When acceleration is applied, the beam deflects, causing strain on the surface. Due to this strain, the resistance of the semiconductor strain gauge changes, and the change in resistance is detected as a voltage signal proportional to the acceleration.

The control unit 82 includes an ignition determination circuit, and a signal from the semiconductor acceleration sensor is input to the ignition determination circuit. When the shock signal from the sensor exceeds a certain value, the control unit 82 starts the calculation, and outputs an operation signal to the igniter 18 of the gas generator 80 when the calculation result exceeds a certain value.

The module case 83 is made of, for example, polyurethane, and includes a module cover 85. The airbag 84 and the gas generator 80 are accommodated in the module case 83 to constitute a pad module, and the pad module is attached to a steering wheel 87 of an automobile.

The airbag 84 is formed of nylon (eg, nylon 66) or polyester, and its bag mouth 86 surrounds the gas outlet 7 of the gas generator. It is fixed to.

When an impact is detected by the semiconductor acceleration sensor 81 at the time of a vehicle collision, the signal is sent to the control unit 82, and when the impact signal from the sensor exceeds a certain value, the control unit 82 starts calculation, When the calculated result exceeds a certain value, an operation signal is output to the igniter 18 of the gas generator 80. Thereby, the igniter 18 operates to ignite the gas generating agent, and the gas generating agent burns to generate gas. This gas is blown into the airbag 84, whereby the airbag breaks the module cover 85 and bulges out, forming a cushion between the steering wheel 87 and the occupant to absorb impact.

[0062]

The gas generator for an air bag according to the present invention uses a non-azide gas generating composition containing a nitrogen-containing organic compound, an oxidizing agent and an acid clay as essential components, and has a bulk density. By using a filter of 3.0 to 5.0 g / cm ³ , even if a liquid combustion residue is generated by the combustion of the gas generating agent, slag is generated, and the slag is filtered by the filter in the gas generator of the present invention. be able to.
As a result, the liquid combustion residue passes through the filter member,
Thereafter, damage to the airbag due to solidification can be eliminated.

The airbag apparatus using the gas generator for an airbag according to the present invention can prevent the airbag from being damaged by the combustion residue, and can be used for protecting the human body mounted on an automobile, an aircraft or the like. Useful for bag devices.

[Brief description of the drawings]

FIG. 1 is a sectional view of a gas generator according to an embodiment of the present invention.

FIG. 2 is a cross-sectional view of a gas generator according to another embodiment of the present invention.

FIG. 3 is a sectional view of a gas generator according to another embodiment of the present invention.

FIG. 4 is a configuration diagram of an airbag device of the present invention.

FIG. 5 is a sectional view of a gas generator according to still another embodiment of the present invention.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 diffuser shell 2 closure shell 3 housing 4 igniter 5 transfer charge 6 gas generating agent 7 coolant / filter 11 gas outlet 22 combustion chamber

Claims (18)

[Claims] 1. A gas generating agent, a housing containing the gas generating agent and having a gas outlet, gas ignition means for igniting the gas generating agent, and a filter for filtering a combustion residue of the gas generating agent. The gas generator for an air bag according to claim 1, wherein a combustion residue in the generated gas discharged from said gas discharge port is 2 g or less. 2. The gas generator for an air bag according to claim 1, wherein the combustion residue in the generated gas discharged from the gas discharge port is 1 g or less. 3. The gas generator for an air bag according to claim 1, wherein the combustion residue in the generated gas discharged from the gas discharge port is 0.7 g or less. 4. The gas generator for an air bag according to claim 1, wherein the gas generating agent is a non-azide gas generating agent. 5. The gas generating agent according to claim 1, wherein the gas generating agent comprises at least a nitrogen-containing organic compound and an oxidizing agent.
The gas generator for an airbag according to any one of claims 4 to 7. 6. The gas generation for an air bag according to claim 1, wherein the gas generating agent comprises at least a nitrogen-containing organic compound, an oxidizing agent, and a slag forming agent. vessel. 7. The gas generator for an air bag according to claim 5, wherein the nitrogen-containing organic compound is nitroguanidine. 8. The gas generator for an air bag according to claim 6, wherein the slag forming agent is acid clay. 9. The gas generating agent according to claim 8, wherein the content of nitroguanidine is 25 to 60% by weight, the content of oxidizing agent is 40 to 65% by weight, and the content of acid clay is 1 to 20% by weight. The gas generator for an airbag according to claim 1. 10. The gas for an air bag according to claim 1, wherein the filter for filtering the combustion residue of the gas generating agent has a bulk density of 3.0 to 5.0 g / cm ^3. Generator. 11. A filter for filtering the residue of combustion of a gas generating agent has a flow rate of 100 × L / min / cm ² at room temperature and 0.3 × 10 ^−2.
Gas generator for an air bag according to claim 10, wherein it is a filter with a pressure drop of ^{~1.5 × 10 -2 kg / cm 2} . 12. A filter for filtering the residue of combustion of a gas generating agent, a stainless steel wire mesh formed in a cylindrical body, and one end of the cylindrical body is repeatedly bent outward to form an annular laminated body. The gas generator for an airbag according to claim 10 or 11, wherein the gas generator is formed by compression molding in a mold. 13. A filter for filtering the residue of combustion of a gas generating agent forms a stainless steel wire mesh in a cylindrical body, presses the cylindrical body in the radial direction to form a plate, and multiplexes the plate into a cylindrical shape. The gas generator for an airbag according to claim 10 or 11, wherein the laminate is formed by winding the laminate into a mold, and the laminate is compression-molded in a mold. 14. A filter for filtering combustion residue of a gas generating agent, having an outer diameter of 45 to 65 mm, an inner diameter of 30 to 55 mm, and a height of 19 to 37.6 mm. 14. The gas generator for an airbag according to claim 13. 15. The filter according to claim 12, wherein the filter for filtering the combustion residue of the gas generating agent has an outer diameter of 55 to 65 mm, an inner diameter of 45 to 55 mm, and a height of 26 to 32 mm. Gas generator for airbags. 16. A filter for filtering a combustion residue of a gas generating agent comprises a wire mesh having a wire diameter of 0.3 to 0.5 mm, and a wire mesh having a wire diameter of 0.5 to 0.6 mm inside. 5-
14. The gas generator for an air bag according to claim 12, wherein the gas generator has a layer of 2.0 mm. 17. A filter for filtering a combustion residue of a gas generating agent comprises a wire mesh having a wire diameter of 0.3 to 0.6 mm and a wire mesh having a wire diameter of 0.5 to 0.6 mm inside. 5-
14. The gas generator for an air bag according to claim 12, wherein the gas generator has a layer of 2.0 mm. 18. An airbag for sensing an impact, an airbag gas generator activated by sensing the impact of the impact sensor, and an airbag which inflates by introducing gas generated by the gas generator. An airbag apparatus comprising: the airbag gas generator according to any one of claims 1 to 17;