Gas generator

The present invention relates to a gas generator suitable for inflating an airbag or the like.

BACKGROUND ART [0002] A gas generator that rapidly expands and deploys an airbag is incorporated in an airbag module mounted in a steering wheel or an instrument panel in order to protect an occupant from an impact generated in a vehicle collision. It has been. Then, the gas generator burns a ignition agent (enhancer) by an igniter (squib) that ignites by an electric signal from a control unit (actor), and burns a gas generator by the flame, so that a large amount of gas generator is used. It generates gas rapidly.

[0003] As a conventional gas generator, a central space corresponding to an ignition chamber of a gas generator and a combustion / filter chamber formed concentrically outside the central space to burn, cool, and collect slag of gas. There is a so-called two-cylinder gas generator with a corresponding annular space.

[0004] As a gas generator of this type, for example, there is one disclosed in Japanese Patent Application Laid-Open No. 9-207705. As shown in FIG. 8, this gas generator is first subjected to friction welding by abutting the upper container 51 having a two-cylinder structure and the lower container 54 having a double short tube structure as the housing of the gas generator. The central space of the obtained housing structure is used as the ignition chamber, and the annular space around the ignition chamber is used as the combustion / filter chamber. The ignition chamber P is equipped with a squib 68 and a gunpowder 69 from below. On the other hand, in the combustion / filter chamber F, a concave ring-shaped lid member 66 having both flanges in cross section is fixed by the flanges 66d and 66e in contact with the burrs 52b and 53b of the upper container 51, respectively. .. Then, the combustion / filter chamber F is formed by accommodating the gas generating agent 57 and the cooling / slag collecting member 60 in order in the radial direction in the annular space sandwiched between the lid member 66 and the upper container 51. There is. Further, ring-shaped cushion members 58 and 59 are interposed on the upper surface and the lower surface of the layer of the gas generating agent 57, respectively. Further, seal members 61 and 62 are interposed on the upper surface and the lower surface of the cooling / slag collecting member 60, respectively. Further, an aluminum foil 64 that closes the gas discharge orifice 53a and an aluminum foil 65 that closes the fire transmission orifice 52a are attached. With such a configuration, a gas generator that can sufficiently withstand an increase in internal pressure due to the gas generated in the gas generation chamber G is obtained.

[0005] However, in the case of this type of two-cylinder gas generator, as shown in FIG. 8, the number of parts constituting the gas generator is large, and the structure is also complicated. Therefore, there is a limit in reducing the manufacturing cost while maintaining the safety of the gas generator. Further, the capacity of the gas generating agent is small, and its use is mainly for the driver's seat, and cannot be used for the passenger seat which requires a large amount of generated gas.

[0006] Further, as a gas generator for an airbag for a passenger seat of an automobile, for example, there is one shown in FIG. As shown in FIG. 9, the gas generator of a conventional passenger seat airbag consists of an outer cylinder 81 having a plurality of gas discharge holes 81a and a lid member 82 that is friction-welded to the open end of the outer cylinder 81. It constitutes the housing 80. An inner cylinder 85 is inserted and arranged in the housing 80. The inner cylinder 85 is provided with a gas permeation hole 85a, and a predetermined amount of the gas generating agent 86 is loaded therein, and the outer cylinder 81 is formed in the annular space between the inner and outer cylinders. A tubular burst plate 83 and a tubular filter member 84 that close the gas discharge hole 81a are arranged. The tubular filter member 84 is packed as tightly as possible in order to reduce the diameter of the housing 80. Further, the lid member 82 is provided with an ignition device 89 including an ignition tool 87 that ignites by collision detection of a collision sensor and a ignition agent 88 ignited by the ignition tool 87.

[0007] As described above, the gas generator of the conventional passenger seat airbag has a tubular shape, and both ends in the longitudinal direction are fixed laterally along the instrument panel in the instrument panel of the automobile. It is attached to the airbag module. For this reason, a large occupied area was required in the instrument panel. In addition, the attachment to the airbag module and the structure are complicated and complicated.

[0008] Further, since the housing has a tubular shape, it is difficult to fill the inside of the housing with the gas generating agent 86 with a high filling efficiency. Therefore, in order to satisfy the recent demand for smaller size and lighter gas generators and to make the amount of gas generated equal to the conventional one, it is necessary to use a gas generator having a large amount of gas generated. Then, a housing that can withstand the high pressure when gas is generated is required.

[0009] According to the present invention, the structure of the gas generator can be simplified, and even when the size and weight are reduced, a large amount of gas is generated, excellent gas generation characteristics can be exhibited, and high safety can be maintained. The purpose is to provide a gas generator to obtain.

[0010] The gas generator of the present invention includes a metal housing formed of an initiator shell and a closure shell, which has a end plate portion and a tubular portion formed continuously from the end plate portion. A combustion chamber formed in the housing and loaded with a gas generating agent that generates high-temperature gas by combustion, a filter member arranged around the combustion chamber, and the gas generation in the combustion chamber mounted on the housing. An ignition means for igniting and burning an agent, a gas generator formed in the housing and having a plurality of gas discharge holes for discharging the gas generated in the combustion chamber, and an initiator shell forming the housing. The end plate portion of either or both of the closure shell has a hemispherical shape or a hemi-elliptical spherical shape, and the ratio of the diameter D of the cylinder portion to the distance H between the end plate portion of the initiator shell and the bottom portion of the end plate portion of the closure shell. The range of H / D is 0.4 to 1.3,<u style="single">The peripheral portion of the gas discharge hole (8) of the filter member (6) bulges inward and has a wall thickness so as to suppress damage due to gas.</u>It is a thing. The diameter D is preferably the value of the length D1 between the outer sides of the closure shell.

[0011] According to such a configuration, even if the number of parts is small and the structure is simple, even if the pressure in the housing is increased by the gas generated by the combustion of the gas generating agent in the combustion chamber. Deformation of the housing can be suppressed. In addition, the number of parts can be reduced and the structure can be simplified. Therefore, the gas generator can be made smaller and lighter, and the manufacturing cost can be significantly reduced. Also, the part where gas is concentrated when outgassing<u style="single">In the periphery of the outgassing hole</u>Damage to the filter can be suppressed, and the gas generated inside the housing can be efficiently cooled by the filter member. In addition, the residue in the generated gas can be efficiently collected.

[0012] Further, the gas generator of the present invention is formed in a metal housing formed of an initiator shell and a combustion chamber, which has a end plate portion and a tubular portion continuously formed from the end plate portion, and in the housing. , A combustion chamber loaded with a gas generating agent that generates high-temperature gas by combustion, a partition plate that divides the combustion chamber into upper and lower chambers, and around the first and second combustion chambers that are partitioned, respectively. First ignition for igniting and burning the arranged first filter member and second filter member, and the gas generating agent mounted on the initiator shell and loaded in the partitioned first combustion chamber and second combustion chamber, respectively. A gas generator having means, a second ignition means, and a plurality of gas discharge holes formed in the housing and discharging gas generated in the partitioned first combustion chamber and second combustion chamber. , The end plate portion of either one or both of the initiator shell and the closure shell forming the housing has a hemispherical shape or a semi-elliptical spherical shape, and has a tubular portion having a diameter D formed continuously from the end plate portion. The range of the ratio H / D between the diameter D of the tubular portion and the distance H between the end plate portion of the initiator shell and the bottom portion of the end plate portion of the closure shell is 0.4 to 1.3, preferably 0.6 to 1.3, more preferably 0.9 to. 1.3<u style="single">The peripheral portion of the gas discharge hole of the filter member is bulged inward and has a wall thickness so as to suppress damage due to gas.</u>.. The diameter D is preferably the value of the length D1 between the outer sides of the closure shell.

[0013] According to such a configuration, even when a plurality of ignition means are used and the pressure in the housing is increased, the deformation of the housing can be suppressed, so that the size and weight can be reduced. As a result, when used as a gas generator for the passenger seat, the occupied area of the gas generator is reduced, and the degree of freedom in designing the instrument panel or the like is increased. Also, the part where gas is concentrated when outgassing<u style="single">In the periphery of the outgassing hole</u>Damage to the filter can be suppressed, and the gas generated inside the housing can be efficiently cooled by the filter member. In addition, the residue in the generated gas can be efficiently collected.

[0014] Further, the gas generator of the present invention has a short axis d1 and a long axis d2 of the cross-sectional shape of the end plate portion in the cross section passing through the housing central axis of the initiator shell and the closure shell having the hemispherical shape or the hemi-elliptical spherical shape. The range of the ratio d1 / d2 is 1 to 0.02, preferably 1 to 0.1, and more preferably 1 to 0.3.

[0015] With such a configuration, it is possible to sufficiently withstand an increase in pressure due to the gas generated in the housing. In addition, the housing can be made smaller and lighter.

[0016] Further, in the gas generator of the present invention, the end plate portion has a substantially semicircular shape or a substantially semicircular shape in which straight lines having three or more sides passing through the central axis of the housing are continuously formed. is there.

[0017] According to such a configuration, the housing can be easily processed.

[0018] Further, in the gas generator of the present invention, the end plate portion has a hemispherical shape with a radius of curvature R, and the range of the ratio D / R with the diameter D of the tubular portion is 0.3 to 2, preferably 0.9 to. 2, more preferably 1.2 to 2. Here, the diameter D is preferably the value of the length D1 between the outer sides of the closure shell. R is the radius of curvature at the hemispherical crown of the closure shell.

[0019] According to such a configuration, it is possible to sufficiently withstand an increase in pressure due to the gas generated in the housing. In addition, the housing can be easily processed. In addition, the housing can be made smaller and lighter.

[0020] Further, in the gas generator of the present invention, the length h of the tubular portion formed in the closure shell is 5 mm or more, preferably 10 mm or more, and more preferably 10 to 30 mm.

[0021] According to such a configuration, the band-shaped seal can be used as a member for sealing the gas discharge hole, and the band-shaped seal can be used as a rupture member.

[0022] [0024] Further, the gas generator of the present invention is described above.<u style="single">plural</u>Outgassing holes zigzag around the housing<u style="single">Array</u>It is what has been done.

[0025] According to such a configuration, it is possible to prevent the gas from concentrating when the gas generated inside the housing is released, and the filter member can be efficiently used.

[0026] Further, in the gas generator of the present invention, the ignition means has a bottomed inner cylinder having a plurality of fire holes around it, a fire-transmitting agent loaded in the inner cylinder, and the transmission. It is composed of an igniter provided in contact with the explosive agent.

[0027] According to such a configuration, the ignition agent is surely ignited by the operation of the igniter, and the flame from the ignition means is surely transmitted to the gas generating agent loaded in the combustion chamber.

[0028] Further, the gas generator of the present invention is described above.<u style="single">plural</u>Fire holes are zigzag around the inner cylinder material<u style="single">Array</u>Has been done.

[0029] According to such a configuration, the heat flow from the ignition means is transmitted to the entire combustion chamber, and the gas generating agent can be efficiently burned.

[0030] Further, in the gas generator of the present invention, the fire transmission hole is formed in the tubular portion of the inner cylinder in an elongated shape along the axial direction.

[0031] According to such a configuration, it is possible to cope with the case where the shape of the combustion chamber expands in the axial direction.

Further, in the gas generator of the present invention, the first ignition means and the second ignition means have a bottomed first inner cylinder and a second inner cylinder having a plurality of fire transmission holes around them. It is composed of a igniter loaded in the first inner cylinder and the second inner cylinder, respectively, and a first igniter and a second igniter provided in contact with the igniter. Is.

[0033] According to such a configuration, the ignition agent loaded in each inner cylinder is surely ignited by the operation of the igniter, and the gas generating agent loaded in each of the partitioned combustion chambers is ignited. The flame from the means is reliably transmitted.

[0034] Further, the gas generator of the present invention is described above.<u style="single">plural</u>The fire transmission holes are zigzag around the first inner cylinder material and the second inner cylinder material.<u style="single">Array</u>It is what has been done.

[0035] According to such a configuration, the heat flow from each ignition means is transmitted to the entire sectioned combustion chamber, and the gas generating agent loaded in each combustion chamber can be efficiently burned. it can.

[0036] Further, in the gas generator of the present invention, the fire transmission hole is formed in a tubular portion of the first inner cylinder material and the second inner cylinder material in an elongated shape along the axial direction. Is.

[0037] According to such a configuration, it is possible to cope with a case where the shape of the combustion chamber is widened in the axial direction.

[0038] Further, the gas generator of the present invention is long so that either one of the first inner cylinder and the second inner cylinder is located in the upper second combustion chamber divided into the two chambers. It is formed on the cylinder of the shaft.

[0039] According to such a configuration, even when the first inner cylinder and the second inner cylinder are arranged side by side, the ignition means for burning the gas generating agent loaded in each combustion chamber is provided. It becomes possible to provide.

[0040] Further, in the gas generator of the present invention, the fire transmission holes formed in either the first inner cylinder or the second inner cylinder formed on the long axis are provided in the two chambers. It is formed by opening only in the upper second combustion chamber that is partitioned.

[0041] According to such a configuration, the gas generating agent loaded in each of the partitioned combustion chambers is burned by the ignition means provided in each combustion chamber. As a result, it is possible to control so that gas can be generated in each combustion chamber.

[0042] Further, in the gas generator of the present invention, the partition plate is sandwiched between the initiator shell and the closure shell.

[0043] According to such a configuration, it is possible to reliably divide the combustion chamber in the housing into two chambers with a small number of components.

[0044] Further, the gas generator of the present invention is loaded with a metal housing formed of an initiator shell and a closure shell, and a gas generator formed in the housing and generating high-temperature gas by combustion. A combustion chamber, a filter member arranged around the combustion chamber, an ignition means mounted on the housing to ignite and burn the gas generator in the combustion chamber, and an ignition means formed in the housing and generated in the combustion chamber. A gas generator having a plurality of gas discharge holes for discharging gas, the housing having a substantially spherical shape.

[0045] Further, the gas generator of the present invention is loaded with a metal housing formed of an initiator shell and a closure shell, and a gas generator formed in the housing and generating high temperature gas by combustion. A combustion chamber, a filter member arranged around the combustion chamber, an ignition means mounted on the housing to ignite and burn the gas generator in the combustion chamber, and an ignition means formed in the housing and generated in the combustion chamber. A gas generator having a plurality of gas discharge holes for discharging gas, the housing having a substantially elliptical spherical shape.

[0046] Further, the gas generator loaded in the gas generator of the present invention has a hollow body shape with both ends closed, preferably a cylindrical shape with both ends closed.

[0047] According to such a configuration, the gas generator has a characteristic that the output is weak for a while after ignition and then the output increases rapidly. This is because with a gas generator of this shape, only the outer surface burns after ignition until the closed end is opened by combustion, so the gas generation rate is slow, and then with the outer surface. Two-sided combustion occurs on the inner surface, and the gas generation rate increases sharply. That is, the gas generating agent having such a shape is a gas generating agent that draws an S-shaped curve as a pressure-time curve in the tank, which is suitable for reducing the harmfulness of the airbag.

[0048] Further, since both ends of the gas generator having such a shape are closed, the compression strength is higher than that of the single-hole tubular shape, and as a result, the gas generator is also resistant to vibration. A gas generator with stable combustion characteristics can be obtained even after being installed in a time vehicle. Further, since the gas generator having a shape in which both ends are closed has high compressive strength, it can be filled in the combustion chamber at a high density, and a smaller and lighter gas generator can be obtained.

[0049] In the passenger seat airbag module of the present invention, the gas generator of the present invention is arranged at the flange portion thereof at the gas generator holding portion of the airbag module, and the gas discharge hole is arranged in the airbag. It is fixed.

[0050] According to such a configuration, the airbag module can be made smaller as compared with the conventional gas generator for the passenger seat. That is, the conventional gas generator for the passenger seat has a cylindrical shape, and is fixed to the gas generator holding portion of the airbag module at both ends in the longitudinal direction with the cylindrical portion turned sideways. Since the gas generator holding portion has a gas discharge hole in the cylindrical portion, the gas generator holding portion has a structure that covers the entire gas generator. Further, since the passenger seat gas generator is installed on the instrument panel that is far from the occupant, it is necessary to generate a large amount of gas, and the cylindrical portion is also long. For this reason, the airbag module incorporating the conventional passenger seat gas generator must inevitably become large. On the other hand, in the gas generator of the present invention, the cylindrical portion having the gas discharge hole can be placed vertically and fixed to the gas generator holding portion of the airbag module by the flange portion existing in the cylindrical portion. The generator holder does not have to cover the entire gas generator. Further, the gas generator of the present invention is smaller than the conventional gas generator for the passenger seat, and as a result, the airbag module can be made smaller.

Further, unlike the conventional airbag module using the passenger seat gas generator, it is not necessary to cover the entire gas generator, so that the structure of the gas generator holding portion of the airbag module can be simplified. it can.

[0052] Further, the airbag module of the present invention has one gas generator.

BEST MODE FOR CARRYING OUT THE INVENTION [0053] Hereinafter, an example of an embodiment of a gas generator according to the present invention will be described with reference to the drawings.

[0054] Fig. 1 shows the present invention.<u style="single">Reference example</u>A cross-sectional view of the gas generator A1 according to the above is shown. In FIG. 1, the gas generator A1 expands and deploys the airbag, and has a substantially spherical housing 3 composed of a metal initiator shell 1 and a combustion shell 2 such as iron, stainless steel, aluminum, and steel. A combustion chamber 5 formed in the housing 3 and loaded with a gas generating agent 4 that generates high-temperature gas by combustion, a filter member 6 arranged around the combustion chamber 5, and a combustion chamber mounted on the housing 3 It is composed of an ignition means 7 for igniting and burning the gas generating agent 4 in 5.

[0055] The closure shell 2 is composed of a tubular portion 9 having a diameter D, a hemispherical end plate portion 10 formed continuously from the tubular portion 9, and a flange portion 12 extending outward from the tubular portion 9. ing. A plurality of gas discharge holes 8 are formed in the cylinder portion 9 in a zigzag manner around the cylinder portion 9.<u style="single">Array</u>(See Fig. 2).<u style="single">plural</u>Gas discharge hole 8 is zigzag<u style="single">Array</u>By doing so, the gas generated in the housing 3 is released without being concentrated. Therefore, damage to the filter member 6 is suppressed. Further, the filter member 6 can be used in a wide range, and the filter member 6 can be used efficiently. These gas discharge holes 8 are zigzag.<u style="single">Array</u>In addition to being done, for example, multiple columns such as 2 columns and 3 columns<u style="single">Array</u>By doing so, the same effect can be obtained.

[0056] Further, the pore diameters of the gas discharge holes 8 are not limited to uniform ones, and gas discharge holes 8 having large and small diameters may be formed alternately. Further, as shown in FIG. 2, the gas discharge holes 8 are arranged in two rows in the axial direction of the tubular portion 9.<u style="single">Array</u>It is not limited to what you do, but there are multiple rows such as 3 rows and 4 rows.<u style="single">Array</u>It may have been. In addition, the hole diameter can be not limited to two types, large and small, but can be set to a plurality of hole diameters such as three types and four types. By controlling the hole diameter of the gas discharge hole 8 in this way, the pressure inside the housing 3 can be controlled. For example, by increasing the hole diameter of the gas discharge hole 8, it is possible to suppress an increase in pressure inside the housing 3. Therefore, the wall thickness of the closure shell 2 and the initiator shell 1 forming the housing 3 can be reduced according to the pressure in the housing 3. Further, the gas generation characteristics can be controlled by controlling the pore diameter according to the type of the gas generating agent 4 to be used. The wall thickness of the initiator shell 1 and the closure shell 2 is preferably in the range of 1.5 to 3 mm.

Further, in these gas discharge holes 8, a rupture member 11 such as a strip-shaped aluminum tape is attached to the inner peripheral portion of the tubular portion 9 to seal the inside of the combustion chamber 5. The length h of the tubular portion 9 is usually 5 mm or more, preferably 5 to 30 mm, and more preferably 10 to 30 mm. This is because the strip-shaped tape can be used as the rupture member 11, and the rupture member 11 can be easily and surely attached.

[0058] The short axis d of the end plate portion 10₁And long axis d₂Ratio d₁/ d₂The range of is usually 1 to 0.02. The preferred range is 1 to 0.1, and the more preferred range is 1 to 0.3. By setting it within such a range, it is possible to sufficiently withstand the internal pressure due to the gas generated in the gas generator.

[0059] Here, the short axis d of the end plate portion 10₁And long axis d₂Is as shown in Fig. 7, and this ratio d₁/ d₂When is 1, it means that the end plate portion 10 has a hemispherical shape.

[0060] When the end plate portion 10 has a hemispherical shape, the range of the ratio D / R between the radius of curvature R and the diameter D of the tubular portion 9 is usually preferably 0.3 to 2. The preferred range is 0.9 to 2, and the more preferred range is 1.2 to 2. The diameter D of the tubular portion 9 is the length D shown in FIG. 1 described later.₁The value of is preferable. The radius of curvature R is the radius of curvature at the crown of the end plate portion 10.

[0061] By forming the end plate portion into a hemispherical shape or a semi-elliptical spherical shape in this way, it is possible to eliminate a portion where the gas pressure of the gas generated in the combustion chamber 5 is concentrated. Therefore, even when the number of component parts of the gas generator is reduced and the structure is simplified, the deformation of the housing can be extremely reduced when gas is generated.

[0062] The initiator shell 1 to be joined to the closure shell 2 by pressure welding, welding, or the like includes a tubular portion 13 and a hemispherical end plate portion 14 continuously formed from the tubular portion 13, similarly to the closure shell 2 described above. It is composed of. An ignition means 7 is provided at the center of the end plate portion 14. Since the tubular portion 13 is formed, the closure shell 2 can be easily joined by pressure welding, welding, or the like. If the closure shell 2 can be directly joined to the closure shell 2 by pressure welding, welding, or the like at the end of the end plate portion 14, the cylinder portion 13 may not be formed, and the initiator shell 1 may be formed only by the end plate portion 14. It can also be configured.

[0063] Similarly to the end plate portion 10 of the closure shell 2 described above, the end plate portion 14 of the initiator shell 1 also has a ratio d of the short axis d1 and the long axis d2.₁/ d₂The range of is usually 1 to 0.02, preferably 1 to 0.1, and more preferably 1 to 0.3. Thereby, when the initiator shell 1 and the closure shell 2 are joined and integrated, the housing 3 having a substantially spherical shape or a substantially ellipsoidal shape can be formed. The ignition means 7 provided in the central portion of the end plate portion 14 includes a bottomed inner cylinder 16 having a plurality of fire transmission holes 15 around it, and a fire transmitting agent 17 loaded in the inner cylinder 16. , It is composed of an igniter 18 provided so as to be in contact with the igniter 17. Enhancers are used to ensure that the gas generator begins to burn. B / KNO commonly used as a fire-retardant 17₃A composition composed of a metal powder and an oxidizing agent represented by the above, a nitrogen-containing compound, a composition containing an oxidizing agent and a metal powder, or a gas generating agent composition can be used. When the content of each component in the fire-retardant 17 is composed of a metal powder and an oxidizing agent, the metal powder component is preferably in the range of 1 to 30% by weight and the oxidizing agent component is preferably in the range of 70 to 95% by weight. In the case of a composition containing an oxidizing agent and a metal powder, the metal powder component is preferably in the range of 1 to 30% by weight, the nitrogen-containing organic compound is preferably in the range of 0 to 40% by weight, and the oxidizing agent component is preferably in the range of 50 to 90%. Further, if necessary, a molding binder may be contained in an amount of 0 to 10% by weight. As the molding binder, a binder that can be generally used as a gas generating agent can be used. As the shape of the fire-retardant 17, it is possible to use a powdery, granular, cylindrical, sheet, spherical, single-hole cylindrical, porous cylindrical, tablet-shaped, or tubular molded body with both ends closed. it can.

[0064] The inner cylinder 16 is fixed to the ignition means holding portion 19 by an arbitrary method such as caulking. The inner cylinder 16 is fixed to the initiator shell 1 by fixing the ignition means holding portion 19 to the end plate portion 14 by an arbitrary method such as welding. Further, the inner cylinder 16 has a long cylinder shape extending from one end side of the combustion chamber 5 formed in the housing 3 to the substantially center of the combustion chamber 5. Around the fire hole 15, a plurality of fire holes 15 are usually zigzag along the axial direction of the inner cylinder 16.<u style="single">Arranged in</u>, Although they are formed in a round hole shape or an elongated hole shape, these fire transmission holes 15 are arranged so that adjacent ones are not arranged side by side along the axial direction of the inner cylinder body 16 as shown in FIG. In a zigzag<u style="single">Array</u>It is preferable that it is. Therefore, the heat flow ejected from the ignition means 7 is efficiently ejected into the entire combustion chamber 5.

[0065] In the housing 3 composed of the closure shell 2 and the initiator shell 1, a filter member 6 is provided along the inner walls of the tubular portions 9 and 13. The filter member 6 is inexpensively manufactured, for example, by forming an aggregate of knitted wire mesh, plain weave wire mesh, crimp-woven metal wire, or wound metal wire in an annular shape. The filter member 6 is pressed toward the inner wall side of the housing 3 by pressing members 20 and 21 provided on the inner surfaces of the end plate portions 10 and 14 of the closure shell 2 and the initiator shell 1, respectively.

[0066] Further, a filter pressing member 24 is provided in the peripheral portion of the gas discharge hole 8 on the outer peripheral portion of the filter member 6. The filter pressing member 24 is a so-called punching metal in which a plate-shaped member having a plurality of holes formed is formed in a ring shape. By providing the filter pressing member 24 on the outer peripheral portion of the filter member 6 in the peripheral portion of the gas discharge hole 8 in this way, the deformation of the filter member 6 due to the pressure at the time of gas discharge is suppressed.

[0067] A gas generating agent 4 is loaded on the inner peripheral portion of the filter member 6. The gas generating agent 4 serves as a combustion chamber 5 that is burned by the heat flow from the ignition means 7.

[0068] The gas generating agent 4 may be a non-azide-based composition, for example, one composed of a fuel, an oxidizing agent, and an additive (binder, slag forming agent, combustion regulator). it can.

[0069] Examples of the fuel include nitrogen-containing compounds. Examples of the nitrogen-containing compound include one or a mixture of two or more selected from a triazole derivative, a tetrazole derivative, a guanidine derivative, an azodicarboxylic amide derivative, a hydrazine derivative, a urea derivative, and an ammine complex.

[0070] Specific examples of the triazole derivative include 5-oxo-1,2,4-triazole, aminotriazole and the like. Specific examples of the tetrazole derivative include, for example, tetrazole, 5-aminotetrazole, aminotetrazole nitrate, nitroaminotetrazole, 5,5'-bi-1H-tetrazole, 5,5'-bi-1H-tetrazole diammonium salt, 5 , 5'-azotetrazole diguanidium salt and the like. Specific examples of the guanidine derivative include guanidine, nitroguanidine, cyanoguanidine, triaminoguanidine nitrate, guanidine nitrate, aminoguanidine nitrate, guanidine carbonate and the like. Specific examples of the azodicarbonamide derivative include, for example, azodicarbonamide. Specific examples of the hydrazine derivative include carbohydrazide, carbohydrazide nitrate complex, dihydrazide oxalate, hydrazine nitrate complex and the like. Examples of the urea derivative include biuret. Examples of the ammine complex include hexaammine copper complex, hexaammine cobalt complex, tetraammine copper complex, tetraammine zinc complex and the like.

[0071] Among these nitrogen-containing compounds, one or more selected from tetrazole derivatives and guanidine derivatives are preferable, and nitroguanidine, guanidine nitrate, cyanoguanidine, 5-aminotetrazole, aminoguanidine nitrate, and guanidine carbonate are particularly preferable. .. The blending ratio of these nitrogen-containing compounds in the gas generating agent 4 varies depending on the number of carbon atoms, hydrogen atoms and other oxidized atoms in the molecular formula, but is usually preferably in the range of 20 to 70% by weight, preferably 30 to 60%. The% by weight range is particularly preferred. In addition, the absolute value of the mixing ratio of the nitrogen-containing compound differs depending on the type of oxidizing agent added to the gas generating agent. However, if the absolute value of the nitrogen-containing compound compounding ratio is larger than the total oxidation theoretical amount, the trace CO concentration in the generated gas increases, while the absolute value of the nitrogen-containing compound compounding ratio is the complete oxidation theoretical amount and it. When it becomes the following, the trace NOx concentration in the generated gas increases. Therefore, the range in which the optimum balance between the two is maintained is most preferable.

[0072] As the oxidizing agent, an oxidizing agent selected from at least one of an alkali metal, an alkaline earth metal, a transition metal, a nitrate containing a cation selected from ammonium, a nitrite, and a perchlorate is preferable. Oxidizing agents other than nitrate, that is, oxidizing agents often used in the air bag inflator field such as nitrite and perchlorate, can also be used, but the number of oxygen in the nitrite molecule is reduced as compared with nitrate, or Nitrate is preferable from the viewpoint of reducing the production of fine powder mist that is easily released to the outside of the bag. Examples of the nitrate include sodium nitrate, potassium nitrate, magnesium nitrate, strontium nitrate, phase-stabilized ammonium nitrate, basic copper nitrate and the like, and strontium nitrate, phase-stabilized ammonium nitrate and basic copper nitrate are more preferable.

[0073] The mixing ratio of the oxidizing agent in the gas generating agent varies depending on the type and amount of the nitrogen-containing compound used, but is preferably in the range of 30 to 80% by weight, and is particularly related to the above-mentioned CO and NOx concentrations. It is preferably in the range of 40 to 75% by weight.

[0074] The binder as an additive can be used as long as it does not significantly adversely affect the combustion behavior of the gas generating agent. Examples of the binder include metal salts of carboxymethyl cellulose, methyl cellulose, hydroxyethyl cellulose, cellulose acetate, cellulose propionate, cellulose acetate butyrate, nitrocellulose, microcrystalline cellulose, guagam, polyvinyl alcohol, polyacrylamide, and polysaccharide derivatives such as starch. Examples thereof include organic binders such as stearate, molybdenum disulfide, synthetic hydroxytalcite, acidic white clay, talc, bentonite, keiso soil, kaolin, silica, and inorganic binders such as alumina.

[0075] The blending ratio of the binder is preferably in the range of 0 to 10% by weight in the case of press molding, and preferably in the range of 2 to 15% by weight in the case of extrusion molding. As the amount added increases, the breaking strength of the molded body increases. However, the number of carbon atoms and hydrogen atoms in the composition increases, the concentration of trace CO gas, which is an incomplete combustion product of carbon atoms, increases, and the quality of the generated gas deteriorates. Moreover, since it inhibits the combustion of the gas generating agent, it is preferably used in the minimum amount. In particular, when the amount exceeds 15% by weight, it is necessary to increase the relative abundance ratio of the oxidizing agent, and the relative ratio of the gas generating compound decreases, which makes it difficult to establish a practical gas generator system.

[0076] Further, as an additive, a slag forming agent can be blended as a component other than the binder. The slag-forming agent is added to facilitate filtration through the filter in the gas generator by interaction with metal oxides, especially from the oxidant component in the gas generator.

[0077] Examples of the slag forming agent include naturally occurring clays mainly composed of aluminosilicates such as silicon nitride, silicon carbide, acid clay, silica, bentonite, and kaolin, synthetic mica, and synthetic kaolinite. Examples thereof include those selected from artificial clay such as synthetic smectite and talc which is a kind of hydrous magnesium silicate mineral. Among these, acidic clay or silica is preferable, and acidic clay is particularly preferable. The blending ratio of the slag forming agent is preferably in the range of 0 to 20% by weight, particularly preferably in the range of 2 to 10% by weight. If it is too large, the linear combustion rate will be lowered and the gas generation efficiency will be lowered, and if it is too small, the slag forming ability cannot be sufficiently exhibited.

[0078] Preferred combinations of the gas generating agent, 5-aminotetrazole, strontium nitrate, synthetic Hidorota including lucite, and the gas generating agent containing silicon nitride, or guanidine nitrate, strontium nitrate, basic copper nitrate, acid clay Examples include gas generating agents.

[0079] Further, a combustion regulator may be added if necessary. As the combustion modifier, metal oxide, ferrosilicon, activated carbon, graphite, or a compound explosive such as hexogen, octogen, 5-oxo-3-nitro-1,2,4-triazole can be used. The blending ratio of the combustion modifier is preferably in the range of 0 to 20% by weight, particularly preferably in the range of 2 to 10% by weight. If it is too large, the gas generation efficiency will be lowered, and if it is too small, a sufficient combustion rate cannot be obtained.

[0080] The gas generating agent shape having the above configuration includes a pellet shape, a columnar shape, a single-hole cylindrical shape, a porous cylindrical shape, a disk shape, and a hollow body shape in which both ends are closed, preferably both ends are closed. A cylindrical one can be used.

[0081] An example of a method for producing a hollow body-shaped gas generating agent used in the present invention with both ends closed will be described. The non-azide composition composed of the nitrogen-containing compound, the oxidizing agent, the slag forming agent and the binder is first mixed by a V-type mixer, a ball mill or the like. Further, water or a solvent (for example, ethanol) can be added and mixed to obtain a wet drug mass. Here, the moist state means a state having a certain degree of plasticity, preferably containing 10 to 25%, more preferably 13 to 18% of water or a solvent. After that, the wet drug mass is directly subjected to an extrusion molding machine (for example, a die and an inner hole pin provided at the outlet) to have an outer diameter of preferably 1.4 mm to 4 mm, more preferably 1.5 mm. It is extruded into a hollow tubular molded body having an inner diameter of ~ 3.5 mm, preferably 0.3 mm to 1.2 mm, and more preferably 0.5 mm to 1.2 mm. After that, the hollow tubular molded body extruded by the extrusion molding machine is pressed at regular intervals to obtain a tubular molded body in which both ends are closed. Usually, the hollow tubular molded body is pressed at regular intervals, cut by folding at each closed recess, and then usually dried in the range of 50 to 60 ° C for 4 to 10 hours, and then dried. , Usually, by performing drying in two steps of drying for 6 to 10 hours in the range of 105 to 120 ° C, a tubular gas generator with a space inside can be obtained with the ends closed. Can be done. The length of the gas generating agent thus obtained is usually in the range of 1.5 to 8 mm, preferably in the range of 1.5 to 7 mm, and more preferably in the range of 2 to 6.5 mm.

[0082] Further, the linear combustion rate of the gas generating agent is measured under constant pressure conditions, and empirically follows the following Vielle's equation. r = aPⁿHere, r is the linear combustion rate, a is a constant, P is the pressure, and n is the pressure index. This pressure index n indicates the gradient of the X-axis pressure logarithmic plot with respect to the logarithm of the Y-axis combustion rate.

[0084] Book<u style="single">Reference example</u>The range of preferable linear combustion rates of the gas generator used in the gas generator according to the above is 70 kgf / cm.²Below 3 to 60 mm / sec, more preferably 5 to 35 mm / sec, and the preferred pressure index range is n = 0.90 or less, more preferably n = 0.75 or less, particularly preferably n = 0.60 or less. is there.

[0085] Further, as a method for measuring the linear combustion speed, a strand burner method, a small motor method, and a closed pressure vessel method are generally mentioned. Specifically, after press molding to a predetermined size, a test piece obtained by applying a restrictor to the surface is used to measure the combustion rate in a high-pressure container by a fuse cutting method or the like. At this time, the linear combustion rate can be measured with the pressure in the high-pressure container as a variable, and the pressure index can be obtained from the above Vielle's equation.

[0086] Further, a cushion member 22 is provided on the end plate portion 10 side of the closure shell 2 of the combustion chamber 5. These cushion members 22 are made of, for example, ceramic fibers, foamed silicon, or the like, and prevent breakage or the like of the gas generating agent 4 loaded in the combustion chamber 5 due to vibration or the like.

[0087] Further, the housing 3 formed by joining the initiator shell 1 and the closure shell 2 has the distance H between the bottoms of the end plate portions 14 and 10 of the initiator shell 1 and the closure shell 2 and the diameter of the tubular portion 9. The ratio H / D to D is usually 0.4 to 1.3, preferably 0.6 to 1.3, and more preferably 0.9 to 1.3. Within such a range, the gas generator can be made smaller and lighter, and can have sufficient strength to withstand the pressure generated by the gas generated in the combustion chamber 5.

[0088] Further, by setting the ratio H / D of the cylinder portions 9, 13 to the diameter D of 0.4 to 1.3, preferably 0.6 to 1.3, and more preferably 0.9 to 1.3, the gas generator can be made smaller. Even when the weight is reduced, the gas generator 4 can be easily filled, and the gas generator can be filled with high filling efficiency. Here, the book<u style="single">Reference example</u>When the gas generator according to the above is used for a passenger seat of an automobile, for example, H is preferably in the range of 45 mm or more and 90 mm or less. As described above, even when the gas generator is made smaller and lighter, the same amount of gas generator as in the conventional case can be filled, and the amount of gas generated does not decrease. Further, in spite of being able to obtain the same amount of gas generated as the conventional one, it is possible to reduce the size and weight as described above because the end plates 14 and 10 are formed in the housing. Therefore, there is no portion where pressure is concentrated inside the housing, it can sufficiently withstand high pressure, and the deformation of the housing when gas is generated is extremely small.

[0089] The gas generator A1 configured as described above is incorporated as a single-cylinder gas generator mainly in an airbag module to be mounted in an instrument panel on the passenger seat side.

[0090] When attached to the airbag module, it can be attached by fixing the flange 12 to the module. Therefore, unlike the conventional tubular gas generator for the passenger seat, the installation to the module is not complicated and can be performed very easily. In addition, since the gas generator is small and lightweight, the occupied area in the instrument panel is small. This increases the degree of freedom in designing the instrument panel.

After being incorporated into the airbag module, the ignition means 7 of the gas generator A1 is connected to a vehicle-side connector (not shown). It can also be used on the driver's side.

[0092] As described above, in the gas generator A1 connected to the automobile, for example, when the collision sensor detects the collision of the automobile, the ignition means 7 is ignited by the squib ignition circuit connected to the ignition means 7. It operates to burn the gas generator 4 in the combustion chamber 5 to generate high temperature gas. At this time, the pressure rises in the combustion chamber 5, but since the housing 3 has a substantially spherical shape, it has sufficient strength to withstand the pressure rise in the combustion chamber 5, and the deformation is extremely small. Then, the high-temperature gas generated in the combustion chamber 5 passes through the filter member 6, breaks through the rupture member 11, and is discharged from the gas discharge hole 8. As the hot gas passes through the filter member 6, the gas is cooled and the residue is collected. Further, since the filter member 6 is provided over substantially the entire area of the combustion chamber 5, the filter member 6 can be effectively used. Therefore, it is possible to release the gas in which the residue is sufficiently collected while being sufficiently cooled.

【0093】<u style="single">Here, an example of an embodiment of the gas generator according to the present invention will be described. The gas generator of this embodiment is</u>As shown in FIG. 3, the wall thickness of the peripheral portion of the gas discharge hole 8 of the filter member 6 installed in the combustion chamber 5 is thicker than the wall thickness of either the upper or lower end portion of the filter member 6.<u style="single">In detail, the peripheral portion of the gas discharge hole 8 of the filter member 6 bulges inward and becomes thick. The gas generator of the present embodiment has the same structure as the above-mentioned reference example except for the filter member 6.</u>Further, although not shown, the filter member 6 may be inclined so that the wall thickness becomes thinner from the upper end portion to the lower end portion.

[0094] In this way,<u style="single">The peripheral portion of the gas discharge hole 8 of the filter member 6 has a wall thickness that bulges inward.</u>As a result, when the gas generated in the combustion chamber 5 is released, the area around the gas discharge hole 8 is released.<u style="single">Thick part</u>Even when concentrated on, damage to the filter member 6 can be suppressed. As a result, it is possible to prevent the filter member 6 from impairing the function of cooling the gas and collecting the residue.

【0095】<u style="single">Hereinafter, other reference examples applicable to the gas generator of the present invention will be described with reference to FIGS. 4 to 7. For example</u>As shown in FIG. 4, one or both of the end plate portions 10 and 14 of the closure shell 2 and the initiator shell 1 are formed in a substantially semicircular shape or abbreviated in which straight lines having three or more sides are continuously formed. It can also have a semi-elliptical shape. As a result, stress concentration can be suppressed even when the pressure inside the housing rises, and the housing can be made smaller and lighter. Moreover, the housing can be easily processed.

[0096] Although not shown, the cross section of the end plate portions 14 and 10 of either the initiator shell 1 or the closure shell 2 is semicircular and the other is semi-elliptical according to the installation location of the gas generator. It can also be shaped.

[0097] Also<u style="single">, Example</u>For example, as shown in FIG. 5, it is possible to divide the inside of the housing 3 into two upper and lower chambers by a partition plate 30. In FIG. 5, the same members as those in FIGS. 1 to 4 are designated by the same reference numerals, and detailed description thereof will be omitted.

[0098] The gas generator A2 shown in FIG. 5 has a metal housing 3 formed by an initiator shell 1 and a closure shell 2, and a gas generator formed in the housing 3 to generate a high temperature gas by combustion. It is composed of a combustion chamber 5 loaded with the agent 4 and a partition plate 30 that divides the combustion chamber 5 into two upper and lower chambers. Then, the first filter member 6a and the second filter member 6b arranged around the first combustion chamber 5a and the second combustion chamber 5b partitioned by the partition plate 30, and the initiator shell 1 are attached to the partition plate. Formed in the housing 3 and the first ignition means 7a and the second ignition means 7b for igniting and burning the gas generating agent 4 loaded in the first combustion chamber 5a and the second combustion chamber 5b partitioned by 30 respectively. It is provided with a plurality of gas discharge holes 8 for discharging the gas generated in the partitioned first combustion chamber 5a and the second combustion chamber 5b.

[0099] Further, either one or both of the initiator shell 1 and the closure shell 2 forming the housing 3 are hemispherical or semi-elliptical spherical end plates 14 and 10, and continuous from the end plate portions 14 and 10. It has cylinders 13 and 9 having a diameter D to be formed. The range of the ratio H / D between the diameter D of the tubular portion 9 and the distance H between the bottoms of the end plate portions 14 and 10 of the initiator shell 1 and the closure shell 2 is usually 0.4 to 1.3, preferably 0.6 to 1.3, and more. It is preferably 0.9 to 1.3. The diameter D of the tubular portion 9 is preferably the value of the length D1 shown in FIG. 5 described later.

[0100] As shown in FIG. 5, the partition plate 30 that divides the combustion chamber 5 in the housing 3 into the first combustion chamber 5a and the second combustion chamber 5b, which are two upper and lower chambers, is formed by pressing one plate material or the like. , The partition portion 31 and the flange portion 32 are formed. The partition portion 31 is formed with a hole 33 through which the second inner cylinder 16b of the second ignition means 7b, which will be described later, is inserted. A step portion 34 is formed around the hole 33, and the second inner cylinder body 16b is restrained by pressing the step portion 16c formed on the second inner cylinder body 16b by the step portion 34. ing. Further, the partition plate 30 is fixed by sandwiching the flange portion 32 between the mating portions of the initiator shell 1 and the closure shell 2.

[0101] In the first combustion chamber 5a and the second combustion chamber 5b, which are divided into two upper and lower chambers by the partition plate 30, the gas generating agent 4 loaded in the respective combustion chambers 5a and 5b is burned. 1 Ignition means 7a and 2nd ignition means 7b are provided.

[0102] The first ignition means 7a provided in the first combustion chamber 5a partitioned under the housing 3 includes a bottomed first inner cylinder 16a having a plurality of fire transmission holes 15 around it. It is composed of a fire-transmitting agent 17 loaded in the first inner cylinder 16a and a first igniter 18a provided in contact with the fire-transmitting agent 17.

[0103] The first inner cylinder body 16a has a bottomed tubular shape having the same diameter, and is fixed to the ignition means holding portion 19a by an arbitrary method such as caulking. The first inner cylinder 16a is fixed to the initiator shell 1 by fixing the ignition means holding portion 19a to the end plate portion 14 by an arbitrary method such as welding. Further, the first inner cylinder 16a has a tubular shape extending from one end side of the first combustion chamber 5a, which is partitioned on the lower side in the housing 3, to the substantially center of the first combustion chamber 5a. Around the fire hole 15, a plurality of fire holes 15 are normally zigzag along the axial direction of the first inner cylinder 16a.<u style="single">Arranged in</u>, Long holes or round holes, but these fire transmission holes 15 are zigzag so that adjacent ones are not juxtaposed along the axial direction of the first inner cylinder 16a.<u style="single">Array</u>It is preferable that it is. As a result, the heat flow ejected from the first ignition means 7a is efficiently ejected into the entire first combustion chamber 5a.

[0104] Further, the second ignition means 7b for burning the gas generating agent 4 of the second combustion chamber 5b partitioned on the upper side of the housing 3 is a bottomed second inner cylinder having a plurality of fire transmission holes 15 around it. It is composed of a body 16b, a igniter 17 loaded in the second inner cylinder 16b, and a second igniter 18b provided in contact with the igniter 17.

[0105] The second inner cylinder body 16b has a bottomed tubular shape having different diameters of the small diameter portion and the large diameter portion, and the step portion 16c is formed, and is fixed to the ignition means holding portion 19a by caulking or the like. It is fixed in any way. The second inner cylinder 16b is fixed to the initiator shell 1 by fixing the ignition means holding portion 19a to the end plate portion 14 by an arbitrary method such as welding. Further, the second inner cylinder 16b is substantially the center of the upper second combustion chamber 5b partitioned by the partition plate 30 from one end side of the first combustion chamber 5a partitioned on the lower side in the housing 3. It has a tubular shape that leads to. Around the cylinder on the 5b side of the second combustion chamber, a plurality of fire transmission holes 15 are normally zigzag along the axial direction.<u style="single">Arranged in</u>, Long holes or round holes, but these fire transmission holes 15 are formed around the second inner cylinder 16b, and adjacent ones are not arranged side by side along the axial direction. Zigzag like<u style="single">Array</u>It is preferable that it is. As a result, the heat flow ejected from the second ignition means 7b is efficiently ejected into the entire combustion chamber 5.

[0106] Further, the second inner cylinder body 16b is fixed to the partition plate 30 by caulking or screwing.<u style="single">This reference example</u>In, a screw is formed on the outer surface of the small diameter portion, and the step portion 34 formed on the partition plate 30 by the nut 35 is screwed and fixed so as to be sandwiched between the step portion 16c and the step portion 16c. There is. As a result, the second igniter 18b is securely fixed and maintained in a restrained state even when the second igniter 18b is operated. Further, as a result, the partition plate 30 can be securely fixed, and the deformation of the partition plate 30 due to the pressure increase when gas is generated in the first combustion chamber 5a can be suppressed. Therefore, it is possible to prevent the gas from bypassing from the first combustion chamber 5a to the second combustion chamber 5b.

[0107] In the ignition means holding portion 19a, the portion where the second ignition means 7b for burning the gas generating agent 4 loaded in the second combustion chamber 5b is fixed is the portion where the first ignition means 7a is fixed. It is formed thicker than the wall. As a result, the position where the second igniter 18b is supported and fixed can be brought closer to the second combustion chamber 5b side, and the combustion efficiency of the gas generating agent 4 in the second combustion chamber 5b can be improved. Further, the embolism 18c of the second igniter 18b, which is supported and fixed to the thick portion of the ignition means holding portion 19a, has the same amount of protrusion of the electrode pin 23 protruding from the embolism 18c as the first igniter 18a. , The shaft length is long. As a result, the strength of the second igniter 18b can be increased. Further, it is not necessary to change the shape of a connector such as a collision sensor (not shown) connected to the electrode pin 23.

[0108] In the first combustion chamber 5a and the second combustion chamber 5b vertically partitioned by the partition plate 30, a second filter member 6b and a first filter member 6a are provided along the inner walls of the tubular portions 9 and 13. It is provided. Each of these filter members 6a and 6b is inexpensively manufactured by, for example, forming an aggregate of knitted wire mesh, plain weave wire mesh, crimp woven metal wire or wound metal wire in an annular shape in the same manner as described above.

[0109] The gas generator A2 configured as described above is incorporated as a two-cylinder gas generator mainly in an airbag module to be mounted in an instrument panel on the passenger seat side. The first ignition means 7a and the second ignition means 7b of the gas generator A2 are connected to vehicle-side connectors (not shown), respectively. Since the gas generator can be made smaller and lighter, it can also be used on the driver's side.

[0110] As described above, in the gas generator A2 connected to the automobile, for example, when the collision sensor detects the collision of the automobile, first, the first combustion chamber 5a having a small load of the gas generator 4 is loaded. The first ignition means 7a is operated by the squib ignition circuit connected to the first ignition means 7a on the side. As a result, the gas generating agent 4 in the first combustion chamber 5a is burned to generate high temperature gas. The high-temperature gas generated in the first combustion chamber 5a passes through the first filter member 6a, temporarily stays in the space S1 formed between the first filter member 6a and the tubular portion 13, and then the partition plate. It passes through the gas passage 36 provided in the flange portion 32 of the 30 and is discharged from the gas discharge hole 8 provided in the tubular portion 9. The gas passage 36 is formed by a notch formed at the end of the flange portion 32, but may be a hole penetrating the flange portion 32.

[0111] Then, after a certain time difference, the second ignition means 7b is activated. As a result, the gas generating agent 4 in the second combustion chamber 5b is burned to generate a high temperature gas. The high-temperature gas generated in the second combustion chamber 5b passes through the second filter member 6b, and in the space S2 formed between the second filter member 6b and the tubular portion 9, the high temperature from the first combustion chamber 5a It mixes with gas and is released from the gas discharge hole 8 provided in the cylinder portion 9, and the airbag is expanded and deployed at once. At this time, the pressure inside the housing 3 rises, but since the housing 3 has a substantially spherical shape, it has sufficient strength to withstand the pressure rise inside the housing 3, and the deformation is extremely small. Then, the high-temperature gas generated in each of the combustion chambers 5a and 5b passes through the filter members 6a and 6b provided in each of the combustion chambers 5a and 5b, breaks the rupture member 11 and is discharged from the gas discharge hole 8. Will be done. Here, regarding the firing order of the first ignition means 7a and the second ignition means 7b, the second ignition means 7b may be operated first, and then the first ignition means 7a may be operated. Further, the operation order can be appropriately controlled according to the impact at the time of collision, such as igniting each of these ignition means 7a and 7b at the same time.

[0112] Also<u style="single">As another reference example</u>It can also be transformed as shown in Fig. 6. In the gas generator A3 shown in FIG. 6, in the gas generator A2 shown in FIG. 5, the shape of the partition plate 30 that divides the combustion chamber 5 in the housing 3 into two chambers is changed to the upper second combustion chamber 5b side. It has a convex spherical shape or an elliptical spherical shape. As a result, even when the amount of the gas generating agent 4 loaded in the first combustion chamber 5a is increased, the deformation of the partition plate 30 is suppressed, and the first combustion chamber 5a to the second combustion due to the deformation of the partition plate 30 are suppressed. It is possible to prevent gas bypass to chamber 5b.

[0113] As described above, even when a plurality of ignition means are used, since the housing has a substantially spherical shape or an ellipsoidal shape, the strength of the housing is improved even when the housing is made smaller and lighter. , It becomes possible to withstand a pressure rise sufficiently.

[0114] Further, in the airbag module of the present invention, the gas generator is fixed by the flange portion 12. The airbag module of the present invention is usually arranged in an instrument panel for a passenger seat. Further, the airbag module of the present invention has one gas generator.<u style="single">Concrete example</u>[0115] Below<u style="single">,Concrete example</u>The gas generator according to the above will be specifically described.

[0116] In the gas generators shown in FIGS. 1 and 2, the distance H between the bottoms of the end plate portion 10 and the end plate portion 14 is 75 mm, the diameter D1 of the cylinder portion 9 is 70 mm, h is 16 mm, and the closure shell 2 is used. A stainless steel material with a wall thickness of 2 mm was molded so that the long axis d2 of the end plate portion 10 was 70 mm, the short axis d1 was 45 mm, and the radius of curvature R on the closure shell side was 45 mm. As for the initiator shell 1, a stainless steel material having a wall thickness of 2 mm was formed so that the long axis d2 of the end plate portion 14 was 67 mm, the minor axis d1 was 42 mm, and the radius of curvature r on the initiator shell side was 20 mm. Then, the ignition means 7 is provided in the initiator shell 1, and the filter member 6 is installed. Then, after the gas generating agent 4 is loaded inside the filter member 6, the cushion material 22 is provided and the closure shell 2 is fitted. Next, the initiator shell 1 and the closure shell 2 were joined by laser welding to form a gas generator.

【0117】<u style="single"> Moth</u>Example of manufacturing a hollow body-shaped gas generator with closed ends used for a screw generator [0118] Guanidine nitrate 43.5% by weight, strontium nitrate 25% by weight, basic copper nitrate 25% by weight, acidic white clay 2.5% by weight, 3% by weight of ethanol and 13% by weight of water are added to the composition mixed with a composition of 4% by weight of polyacrylamide, mixed and kneaded to form a kneaded mass, and a die with an inner diameter of 2 mm and an outer diameter of 0.5 mm are included at the outlet. Extrude at an extrusion pressure of 8 MPa with an extruder equipped with a pin for holes, and while taking out the extruded rod-shaped molded body with a take-up belt, send it out between the molding gears, and the intervals of 4.4 mm by the convex teeth of the molding gears. After cutting by folding at the recessed portion, the mixture was dried at 55 ° C for 8 hours and then dried at 110 ° C for 8 hours to obtain a gas generating agent.

INDUSTRIAL APPLICABILITY The gas generator according to the present invention is configured as described above, and the number of component parts of the gas generator is increased by forming the housing into a substantially spherical shape or an ellipsoidal shape. Even when the number of gas generators is reduced and the structure is simplified, it is possible to sufficiently withstand an increase in the internal pressure of the housing due to the gas generated by the combustion of the gas generator. Therefore, the deformation of the housing when gas is generated can be made extremely small. In addition, since the number of parts can be reduced and the structure can be simplified, the gas generator can be made smaller and lighter. In addition, it has the effect of significantly reducing the manufacturing cost while maintaining the safety of the gas generator.

BRIEF DESCRIPTION OF THE DRAWINGS [Fig. 1] Fig. 1 shows the present invention.<u style="single">Reference example</u>It is sectional drawing of the gas generator of. FIG. 2 shows the present invention.<u style="single">Reference example</u>It is an external view of the gas generator in. FIG. 3 shows the present invention.<u style="single">Fruit</u>It is sectional drawing of the gas generator of the embodiment. FIG. 4 shows another of the present invention.<u style="single">Reference example</u>It is sectional drawing of the gas generator of. FIG. 5 shows another of the present invention.<u style="single">Reference example</u>It is sectional drawing of the gas generator of. FIG. 6 shows another of the present invention.<u style="single">Reference example</u>It is sectional drawing of the gas generator of. FIG. 7 shows the present invention.<u style="single">Reference example</u>It is a figure for demonstrating the short axis d1 and the long axis d2 of the end plate part of the gas generator which concerns on. FIG. 8 is a cross-sectional view showing an example of a conventional two-cylinder gas generator. FIG. 9 is a cross-sectional view showing an example of a conventional gas generator for a passenger seat.