JP3028200U - Gas generator for airbag - Google Patents

Abstract

(57) [Summary] (Correction) [Problem] To provide a gas generator sufficiently reliable in terms of cooling and slag collecting performance. SOLUTION: In a central space portion corresponding to the ignition chamber P of the gas generating agent and an annular space portion corresponding to the combustion / filter chambers G and F, the gas generating agent 7 is housed on the inner side and on the outer side. A cooling / slag collecting member 10 is provided, and a fire transfer orifice 2a and a gas discharge orifice 3a are provided.
A gas generator for an air bag of a two-chamber structure in which a metal foil 14 for closing at least the gas discharge orifice 3a is attached to the inner surface of the annular space portion, and the gas discharge orifice 3a is arranged on the axial center side. Cover that covers the area corresponding to the orifice opening area formed on the inner peripheral surface of the cooling / slag collecting member 10 by the intersection of the virtual cylinder formed when it is virtually extended and the inner peripheral surface of the cooling / slag collecting member 10. The plate 30 was attached.

Description

[Detailed description of the device] [Technical field to which the device belongs]

The present invention relates to a gas generator for inflating an airbag, which is a vehicle occupant protection device.

[0002]

[Prior art]

 A so-called two-chamber having a central space portion corresponding to the ignition chamber of the gas generating agent and an annular space portion concentrically formed outside the combustion chamber for combustion / cooling / slag collection of gas / corresponding to a filter chamber As a gas generator for an air bag having a structure, there is a prior patent application (Japanese Patent Application No. 7-333902) filed by the applicant of the present invention, which is versatile enough to meet all demands for size reduction, weight reduction, and cost reduction. It is a high gas generator. That is, the gist of the gas generator according to the preceding example is, as shown in FIG. 3, first, as a housing of the gas generator, an upper container 1 of a double pipe structure and a lower container 4 of a double short pipe structure. The central space of the housing structure, which is obtained by butting and friction welding with each other, is the ignition chamber, and the annular space around it is the combustion / filter chamber. The squib 18 and transfer charge 19 are installed in the ignition chamber P from below. On the other hand, in the combustion / filter chamber, a ring-shaped lid member 16 having a cross section with both flanges is fixed by abutting the burrs 2b, 3b of the upper container 1 with the respective flanges 16d, 16e. The combustion / filter chamber is formed by accommodating the gas generating agent 7 and the cooling / slag collecting member 10 in the radial direction in the annular space sandwiched between the lid member 16 and the upper container 1. . Further, ring-shaped cushion members 8 and 9 are provided on the upper surface and the lower surface of the layer of the gas generating agent 7, respectively. Further, sealing members 11 and 12 are provided on the upper surface and the lower surface of the cooling / slag collecting member 10, respectively. Further, an aluminum foil 14 for closing the gas discharge orifice 3a and an aluminum foil 15 for closing the fire transfer orifice 2a are attached. With this structure, it is possible to adjust the combustion pressure while satisfying all the requirements of downsizing, weight saving, and cost reduction, and it is safe, has good performance, and is a versatile gas generator for airbags. Can be achieved.

[0003]

[Problems to be solved by the device]

 However, when the performance test using various gas generating agents was continued with respect to the above-mentioned prior example, some points were found to be improved in the process. That is, as described above, the removal of the partition member (not shown) that shuts off the burned portion G and the filter arrangement portion F is one of the constituent requirements, which makes it possible to reduce the size, weight, and cooling.・ Cooling and slag collection efficiency has been improved by increasing the amount of slag collection material charged. However, on the other hand, since there is no such partitioning member, depending on the type of gas generant and the combustion conditions, the gas that ignites and burns is not sufficiently evenly distributed in the circumferential direction in the combustion section G and is cooled / cooled. It has been found that a case where a so-called concentrated drift is generated through the slag collecting member 10 toward the gas discharge orifice 3a may occur. In this case, the cooling and slag collecting member 10 does not sufficiently improve the cooling and slag collecting efficiency, and in an extreme case, the cooling and slag collecting member 10 is melted and loses its cooling and slag collecting effect. It has been found that there is a case where it is further reduced. Therefore, in order to maximize the advantages of the gas generator of the preceding example, there is a demand for the development of an improved gas generator with sufficient reliability, particularly in terms of cooling and slag collection performance. Although we have continued to make intensive investigations in order to respond to the above, since we have seen some results, we will disclose it here.

That is, of the present invention, the invention according to claim 1 is a safe and versatile gas generator that meets all the demands of downsizing, weight saving, and cost reduction. The aim is to provide a gas generator that is also reliable in terms of collection performance. The invention according to claim 2 is intended to provide a gas generator which can further secure the effect of the invention according to claim 1. In addition to the object of the invention according to claim 1, the invention according to claim 3 aims to provide a gas generator which can facilitate the assembling work and contribute to the reduction of the manufacturing cost. It was done. In addition to the object of the invention according to claim 1 to claim 4, the invention according to claim 4 aims to provide a gas generator excellent in cooling / slag collecting performance in particular. Is. Further, the invention according to claim 5 is a gas generator capable of exhibiting the effects of the invention according to any one of claims 1 to 4, even when a fuel having a large amount of gas generated per unit mass is used as the gas generating agent. Is intended to be provided.

[0005]

[Means for Solving the Problems]

 Among the inventions capable of achieving the above object, the invention according to claim 1 is formed by friction welding of inner pipes and outer pipes on the open side of a bottomed double pipe by butting. Of the central space that corresponds to the ignition chamber of the generant, and the annular space that is concentrically formed outside it and that performs combustion, cooling, and slag collection of gas, and that corresponds to the filter chamber, the annular space From the center of the shaft toward the outer side in the radial direction, a gas generating agent is housed on the inner side, a cooling / slag collecting member is installed on the outer side, and the central space and the annular space A two-chamber structure in which a fire transfer orifice that communicates with each other and a gas discharge orifice that communicates the outside with the annular space are provided, and a metal foil for closing at least the gas discharge orifice is attached to the inner surface of the annular space. A gas generator for an airbag of It is formed on the inner peripheral surface of the cooling / slag collecting member by the intersection of the virtual cylindrical surface formed when the gas discharge orifice is assumed to extend to the axial center side and the inner peripheral surface of the cooling / slag collecting member. A cover plate that covers the area corresponding to the orifice opening area is attached to the inner peripheral surface of the cooling / slag collecting member.

As described above, by covering the area corresponding to the opening area of the gas discharge orifice on the inner peripheral surface of the cooling / slag collecting member, the combustion gas in the combustion section can be cooled and cooled by the conventional method. It is no longer said that the gas flows concentratedly in the collecting member toward the gas discharge orifice. In other words, the combustion gas that hits each cover plate once spreads to the surroundings with each cover plate. As a result, in the entire combustion section, the combustion gas is appropriately dispersed in the circumferential direction. Therefore, the proportion of the volume portion corresponding to the flow path of the combustion gas in the entire volume of the cooling / slag collecting member increases, and the cooling / slag collecting efficiency can be improved accordingly. As a result, the gas generator of the preceding example is improved, that is, it is a safe and versatile gas generator that meets all the requirements of downsizing, weight saving, and cost reduction. It is possible to make the gas generator reliable in terms of collecting performance.

Further, the invention according to claim 2 is, in the constitution of the invention according to claim 1, a cylinder in which the cover plate entirely covers only the upper side of the inner peripheral surface of the cooling / slag collecting member. It is characterized by being shaped like a cover ring. With such a configuration, the gas flow path in the upper part of the combustion / filter chamber, that is, the gas flow path from the combustion part to the filter part is blocked, so that the gas that ignites and burns is above the combustion part. After being sufficiently evenly dispersed in the circumferential direction, all the gas enters from the lower side of the cooling / slag collecting member and flows toward the gas discharge orifice while rising inside the member. Therefore, the proportion of the volume portion corresponding to the flow path of the combustion gas in the entire volume of the cooling / slag collecting member is further increased, and the cooling / slag collecting efficiency can be further improved. As a result, it is possible to provide a gas generator that can further secure the effect of the device according to the first aspect.

Further, the invention according to claim 3 is the cylindrical body in which the cover plate is attached along the entire inner peripheral surface of the cooling / slag collecting member in the configuration of the invention according to claim 1. A gas passage orifice is formed on the lower side of the member. As a result, in addition to the effect of the invention described in claim 1, it is possible to provide a gas generator that can facilitate the assembly work and contribute to the reduction of the manufacturing cost.

Further, in the invention according to claim 4, in the structure of the invention according to claims 1 to 3, the cooling / slag collecting member is composed of a two-layer mesh member radially consisting of an inner layer part and an outer layer part. A mesh member having a mesh that is coarser than that of the mesh member arranged in the outer layer portion is arranged in the inner layer portion. As a result, by taking advantage of the characteristic of the inner layer part consisting of a coarse mesh member that the resistance to gas flow is low, the efficiency of gas dispersion in the cooling / slug collecting member is improved, and the cooling / slag collecting efficiency is further improved. It is possible to provide a gas generator that can be excellent.

Further, the invention according to claim 5 is, in the constitution of the invention according to claims 1 to 4, characterized in that the gas generating agent is a compound having a nitrogen atom-containing organic substance as a main fuel component. And When this type of gas generating agent, which has a large calorific value per unit mass, is used as the gas generating agent in the prior example, the adverse effect caused by the concentrated drift of the combustion gas is further increased, which is a problem. In the gas generator, even when such a gas generating agent is used, the combustion gas flowing from the combustion section to the filter section is surely dispersed, and concentrated drift is eliminated. Therefore, it can be said that the degree of the effect obtained by the present invention is more remarkable when the non-azide type gas generating agent is used than when the so-called azide type gas generating agent is used. .

[0011]

[Embodiment of device]

 Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 (a) is a cross-sectional view of an essential part showing an embodiment of the present invention (the invention according to claim 1). The same components as those of the conventional gas generator shown in FIG. 3 are designated by the same reference numerals.

In FIG. 1 (a), first, the housing of the gas generator has an upper container 1 made of aluminum having a double pipe structure with one end (upper end in the figure) closed, and an opening at the center of the shaft. By friction-welding the lower aluminum container 4 having a double short pipe structure having the two ends of the inner cylindrical walls 2 and 5 and the ends of the outer cylindrical walls 3 and 6 to each other, The structure has a central space and an annular space around it. In the central space, the squib 18 and the transfer charge 19 are installed from below to form an ignition chamber P.

In the annular space, first, as the ring-shaped lid member 16, a metal tubular member having a double short pipe structure having a bottom portion 16c between the outer tubular wall 16b and the inner tubular wall 16a. The bottom portion 16c has a concave cross-sectional shape that crawls on the inner surface of the lower lid 21 of the lower container 4, and the inner peripheral edge portion 16d and the outer peripheral edge portion 16e thereof respectively have an upper container It is fixedly arranged so as to abut the burr 2b and the burr 3b. Then, the gas generating agent 7 and the cooling / slug collecting member 10 are sequentially stored in the annular space sandwiched by the upper container 1 and the ring-shaped lid member 16 in the radial direction to form a combustion / filter chamber. ing. G shows a combustion part, F shows a filter arrangement part. As the gas generating agent 7, a compound containing a nitrogen atom-containing organic substance as a main fuel component (hereinafter, referred to as “explosive composition”) and having a combustion characteristic that a large amount of gas is generated per unit mass is used. Is preferred. As such an explosive composition, specifically, it is preferable to employ a mixture of the respective components selected from the following groups (a) to (c). (A) Nitrogen atom-containing organic substances that are the main fuel components that generate gas upon combustion decomposition are azodicarbonamide, carbohydrazide, dicyandiamide, aminotetrazole, aminoguanidine, triaminoguanidine nitrate, nitroguanidine, triazole, Selected from the group consisting of tetrazole, azobitetrazole, bitetrazole, or salts thereof. (B) An oxidizer that burns the main fuel component. (C) A combustion control agent as a catalyst for controlling the oxidation reaction. By selecting a nitrogen atom-containing organic substance from the above group (a), it is possible to use a gas having a particularly high content of nitrogen atoms in the molecule, substantially inexpensive, and easily available in large quantities, so that inexpensive gas generation is possible. It can be fully applied to the manufacture of vessels.

In using the above explosive composition, it is preferable to adjust the particle size in advance, for example, it is preferable to adjust the number-based 50% average particle size to be 5 to 80 μm. Specific examples of the oxidizing agent that can be used include nitrates, nitrites, oxohalogenates and the like. Of these, nitrates are preferable, and potassium nitrate is particularly preferable. The amount of the oxidizing agent added is preferably 50% by weight or more of nitrate in the explosive composition. This improves the combustion characteristics of the generated gas, is because especially useful N O _X reduction effect. When using an oxidant, it is preferable to adjust the particle size to the same extent as that of the explosive composition in advance.

Further, the combustion control agent is preferably a substance selected from the following groups. One or more of zirconium, hafnium, molybdenum, tungsten, manganese, nickel, iron or its oxides or sulfides. One or more of carbon, sulfur or phosphorus. A mixture of the above and. Such a combustion modifier has a function of adjusting the oxidation reaction (combustion) rate of the above-mentioned oxidizer and the nitrogen atom-containing organic substance which is the main fuel component. The amount of the combustion modifier added may be 10% or less with respect to the weight of the explosive composition in order not to impair the gas generation amount per unit explosive composition and to prevent excessive combustion residue. Preferred. Even when the combustion modifier is used, it is preferable to adjust the particle size so that, for example, the number-based 50% average particle size is 10 μm or less.

Further, cushion members 8 and 9 are provided on the lower surface of the upper lid 20 and the upper surface of the ring-shaped lid member 16 located in the combustion section G of the combustion / filter chamber, respectively. Further, an aluminum foil 14 for closing the gas discharge orifice 3a is attached to the inner peripheral surface of the outer cylindrical wall 3 of the upper container 1, and the outer peripheral surface of the inner cylindrical wall 2 (the peripheral surface on the combustion section G side). Also, an aluminum foil 15 is attached so as to close the fire transfer orifice 2a. Further, between the lower surface of the upper lid 20 and the upper surface of the cooling / slag collecting member 10 located in the filter arrangement portion F of the combustion / filter chamber, and between the lower surface of the cooling / slag collecting member 10 and the upper surface of the ring-shaped lid member 16. The ring-shaped seal members 11 and 12 are interposed between and. In addition, at the corner below the combustion / filter chamber and on the side of the ignition chamber P, the portion from the inner cylindrical wall 16a to the tip of the ring-shaped lid member 16 is brought into contact with the burr 2b of the inner cylindrical wall 2 without any trouble. A guide member 17 for forming such a space S in the circumferential direction is internally provided.

Further, a virtual cylinder formed by assuming that the gas discharge orifice 3a is extended with respect to the axial center side and the inner peripheral surface 10a of the cooling / slag collecting member 10 intersect with each other so that the member 10 A thin plate-shaped aluminum cover plate 30 covering the area corresponding to the orifice opening area formed on the inner peripheral surface 10a of the above is spot-welded to the inner peripheral surface 10a side of the cooling / slag collecting member 10. Here, "a cover plate that covers the area corresponding to the orifice opening area" refers to a cover plate that covers each orifice independently and covers the area corresponding to multiple orifices collectively. It is meant to include the cover plate, and there is no special limitation on its shape or size. FIG. 1 shows an example in which a cover plate having a diameter larger than the opening diameter Dφ of the gas discharge orifice 3a is covered so as to correspond to each orifice.

As a result, the combustion gas in the combustion section G does not concentrate in the cooling / slag collecting member 10 toward the gas discharge orifice 3a as in the conventional case. That is, the combustion gas hitting each cover plate 30 once spreads to the surroundings in each cover plate 30. As a result, when viewed in the entire combustion section G, a situation occurs in which the combustion gas is appropriately dispersed in the circumferential direction. Therefore, the proportion of the volume portion corresponding to the flow path of the combustion gas in the entire volume of the cooling / slag collecting member 10 increases, and the cooling / slag collecting efficiency can be improved accordingly. As a result, an improved version of the gas generator of the preceding example shown in FIG. 3, that is, a safe and versatile gas generator that meets all the requirements of downsizing, weight reduction, and cost reduction, -It can be a gas generator that is also reliable in terms of slag collection performance.

Further, in the gas generator of the preceding example (see FIG. 3), when the calorific value of the gas generating agent 7 is large, the degree of the adverse effect caused by the concentrated drift of the combustion gas is further increased. It was On the other hand, in the gas generator according to the embodiment of the present invention, even when the gas generating agent 7 having a large heat generation amount is used, the combustion gas flowing from the combustion section G to the filter arrangement section F is reliably dispersed and concentrated. The drift is eliminated. Therefore, it can be said that the degree of the effect obtained by the present invention is more remarkable when the non-azide type gas generating agent is used than the effect obtained by using the so-called azide type gas generating agent.

Next, FIG. 1B is a perspective view of a cover plate 31 according to an embodiment of the present invention. That is, what is different from the cover plate 10 according to the embodiment of FIG. 1 (a) is a cylindrical cover ring that entirely covers only the upper side of the inner peripheral surface 10a of the cooling / slag collecting member 10. In point. As a result, the gas flow path in the upper part of the combustion / filter chamber, that is, the gas flow path from the combustion section G to the filter arrangement section F is blocked, so that the gas that is ignited and burned circulates above the combustion section G. After being sufficiently evenly distributed in the direction, all the combustion gas enters from the lower side direction of the cooling / slag collecting member 10 and flows upward toward the gas discharge orifice 3a while rising inside the member 10. Therefore, the proportion of the volume portion corresponding to the flow path of the combustion gas in the entire volume of the cooling / slag collecting member 10 is further increased, and the cooling / slag collecting efficiency can be further improved. This makes it possible to provide a gas generator having higher cooling / slag collecting performance than the gas generator according to the embodiment of FIG. 1 (a).

Next, FIG. 1C is a perspective view of a cover plate 32 according to a third aspect of the present invention. That is, what is different from the cover plate 10 according to the embodiment of FIG. 1 (a) is that it is a cylinder attached along the entire inner peripheral surface 10a of the cooling / slag collecting member 10, and the lower side of the cylinder. The gas passage orifice 32a is formed at the point. If such a cover plate 32 is adopted, the work for spot welding when attaching the cover plate 10 or 31 can be omitted, while the function of dispersing combustion gas and increasing the gas flow path length can be omitted. Can be secured as well. Therefore, it is possible to provide a gas generator that can further facilitate the assembly work and contribute to the reduction of the manufacturing cost, as compared with the gas generators according to the embodiments of FIGS. And As a modification of the cover plate 32, the cover plates 33 and 34 shown in FIGS. 1D and 1E may be used. Reference numerals 33a and 34a are gas passage orifices. The invention is not limited to these modified examples, and various shapes, sizes, arrangements, etc. can be adopted as the gas passage orifices.

Next, FIG. 2 is a cross-sectional view of an essential part showing an embodiment of the present invention (the invention according to claim 4). The difference from the embodiment of FIG. 1A is the configuration of the cooling / slag collecting member 10. That is, the cooling / slag collecting member 10 is formed from a two-layer mesh member of the inner layer portion 40 and the outer layer portion 41 in the radial direction, and is arranged in the outer layer portion 41 in the inner layer portion 40. The feature is that a mesh member having a mesh coarser than that of the mesh member is arranged. The inner layer portion 40 made of such a coarse mesh member has a characteristic that the resistance against the gas flow is small.

As a result, the gas combusted in the combustion section G is sufficiently evenly distributed in the circumferential direction on the upper side of the combustion section G, and then all the combustion gas is directed to the lower side of the cooling / slag collecting member 10. When entering from above, the combustion gas splits in the inner layer portion 40 as shown by the arrow in the figure, travels almost all over the outer layer portion 41 from above to below, and then flows toward the gas discharge orifice 3a. Takes on the appearance of. As described above, by improving the dispersion efficiency of the combustion gas in the inner layer portion 40, the ratio of the volume portion corresponding to the flow path of the combustion gas in the total volume of the member 10 is further increased, and the cooling / slag collecting efficiency is improved. Further improvement can be planned.

Next, how to assemble the gas generator will be described by taking the embodiment shown in FIG. 1 as an example. First, an aluminum foil 14 for closing the gas discharging orifice 3a is attached to the inner peripheral surface of the outer cylindrical wall 3 of the upper container 1 having a bottomed double tube structure, and the outer peripheral surface of the inner cylindrical wall 2 is also adhered. After the aluminum foil 15 for closing the fire transfer orifice 2a is attached, the upper container 1 is fixed on a pedestal (not shown) so that its opening faces upward. Next, the cylindrical cooling / slag collecting member 10 is loaded along the inner peripheral surface of the outer cylindrical wall 3 from above (from the lower side in the drawing) into the annular space portion, but the upper and lower end surfaces are preliminarily covered by the seals. The base members 11 and 12 are attached and a cover plate 30 is attached to a predetermined position on the inner peripheral surface side.

After charging the cooling / slag collecting member 10, the ring-shaped cushion member 8 is laid on the inner surface of the upper lid 20, and the gas is provided in the space between the cooling / slag collecting member 10 and the inner cylindrical wall 2. Charge the generant 7. When a cylindrical cover ring as shown in FIGS. 1 (c) to 1 (d) is adopted as the cover plate, the inner peripheral surface of the cooling / slag collecting member 10 is laid before the cushion member 8 is laid. All you have to do is load along the whole. Now, when the gas generating agent is charged up to about 7 minutes in the space, the charging is temporarily stopped. Then, the stepped short tubular guide member 17 is fitted to the stepped portion 2c of the inner cylindrical wall 2 with the small diameter side thereof facing down. After that, the charging of the gas generating agent 7 is continued up to the height of the upper end of the guide member 17 (at the same level as or slightly lower than the upper end of the seal member 12).

After charging the gas generating agent 7, a ring-shaped cushion member 9 is laid on the upper surface thereof. Next, the ring-shaped lid member 16 is attached so that its outer cylindrical wall 16b is along the outer peripheral surface of the cooling / slag collecting member 10 and its inner cylindrical wall 16a is along the inner peripheral surface of the guide member 17. . Next, the transfer charge 19 enclosed in a predetermined thin container is loaded into the central space. Next, the bottom container 4 having a double short tube structure with a bottom, to which the squib 18 has been attached in advance, has the inner cylindrical wall 5 and the outer cylindrical wall 6 respectively formed by the inner cylindrical wall 2 and the outer cylindrical wall 3 of the upper container 1. The tip end surfaces are brought into contact with each other. In this state, the lower container 4 is gripped with respect to the fixed upper container 1 and is pushed while rotating with a predetermined pressure. As a result, the contact surface is melted by frictional heat, and the butt welding of the upper container 1 and the lower container 4 is completed. At the end, the outer peripheral edge portion 16e and the inner peripheral edge portion 16d of the ring-shaped lid member 16 are in close contact with the burrs 2b and 3b of the upper container 1 in the circumferential direction and are pressed by the burrs 2b and 3b. ing. Thus, the assembly work of the gas generator is completed.

[0027]

[Effect of device]

 The invention according to claim 1 of the present invention comprises a virtual cylinder formed when a gas discharge orifice is assumed to extend perpendicularly to the axial center side, and an inner peripheral surface of a cooling / slag collecting member. A cover plate is attached to the inner peripheral surface side of the cooling / slag collecting member so as to cover the orifice opening area corresponding region formed on the inner peripheral surface of the member by intersecting. Therefore, by covering the area of the inner peripheral surface of the cooling / slag collecting member that corresponds to the opening area of the gas discharge orifice, the combustion gas in the combustion section can generate gas inside the cooling / slag collecting member as in the conventional case. There will be no concentrated flow towards the discharge orifice. In other words, the combustion gas that hits each cover plate once spreads to the surroundings on each cover plate. As a result, when viewed in the entire combustion section, the combustion gas is appropriately dispersed in the circumferential direction. Therefore, the proportion of the volume portion corresponding to the flow path of the combustion gas in the total volume of the cooling / slag collecting member increases, and the cooling / slag collecting efficiency can be improved accordingly. As a result, the gas generator of the preceding example has been improved, that is, a safe and versatile gas generator that meets all the demands for downsizing, weight saving, and cost reduction. It is possible to make the gas generator reliable in terms of performance.

Further, in the invention according to claim 2, the cover plate is a cylindrical cover ring which entirely covers only the upper side of the inner peripheral surface of the cooling / slag collecting member. As a result, the gas flow path in the upper part of the combustion / filter chamber, that is, the gas flow path from the combustion section to the filter section is blocked, so the gas that ignites and burns is sufficiently even in the circumferential direction above this combustion section. Then, all the gas enters from the lower side of the cooling / slag collecting member and rises inside the member toward the gas discharge orifice. Therefore, the proportion of the volume portion corresponding to the flow path of the combustion gas in the total volume of the cooling / slag collecting member is further increased, and the cooling / slag collecting efficiency can be further improved. As a result, it is possible to provide a gas generator that can further secure the effect of the device according to the first aspect.

Further, the invention according to claim 3 is a cylindrical body in which the cover plate is attached along the entire inner peripheral surface of the cooling / slag collecting member, and a gas passage through is provided below the member. The Liffith is formed. Therefore, in addition to the effect of the invention described in claim 1, it is possible to provide a gas generator that can facilitate the assembly work and contribute to the reduction of the manufacturing cost.

Further, in the invention according to claim 4, the cooling / slag collecting member is formed from a two-layer mesh member of an inner layer portion and an outer layer portion in the radial direction, and the inner layer portion has an outer layer. A mesh member having a mesh that is coarser than that of the mesh member arranged in the section is arranged. Therefore, the cooling / slag collecting efficiency is further improved by improving the gas dispersion efficiency in the cooling / slag collecting member by taking advantage of the characteristic that the inner layer part made of the coarse mesh member has a low resistance to the gas flow. It is possible to provide a gas generator that can be excellent.

Further, in the invention according to claim 5, the gas generating agent is a compound having a nitrogen atom-containing organic substance as a main fuel component. For this reason, in the gas generator according to the preceding example, when a gas generating agent having a combustion characteristic that a large amount of gas is generated per unit mass is used, the extent of the adverse effect caused by the concentrated drift of the combustion gas is small. Although it became a problem even further, the gas generator of the present invention surely disperses the combustion gas flowing from the combustion section to the filter section even when such a gas generating agent is used, thereby eliminating concentrated non-uniform flow. It Therefore, the degree of the effect obtained by the present invention is more remarkable when the non-azide type gas generating agent is used than the effect obtained by using the so-called azide type gas generating agent. I can say.

[Brief description of drawings]

FIG. 1 is a sectional view of an essential part showing an embodiment of the present invention,
(A) is a figure which shows one Embodiment of the invention of Claim 1,
(B) is a perspective view of the cover plate according to the invention of claim 2, and (c) to (e) are perspective views of the cover plate according to the invention of claim 3.

FIG. 2 is a sectional view of an essential part showing an embodiment of the present invention (an invention according to claim 4).

FIG. 3 is a cross-sectional view of an essential part showing a conventional gas generator.

[Explanation of symbols]

 1 Upper Container 2 Inner Cylindrical Wall 2a Fire Transfer Orifice 3 Outer Cylindrical Wall 3a Gas Release Orifice 4 Lower Container 5 Inner Cylindrical Wall 6 Outer Cylindrical Wall 7 Gas Generating Agent 8 Cushion Member 9 Cushion Member 10 Cooling / Slag Collection Member 11 , 12 Seal member 14, 15 Aluminum foil 16 Lid member 17 Guide member 18 Squib 19 Transfer agent 30-34 Cover plate 40 Inner layer part 41 Outer layer part F Filter placement part G Combustion part P Ignition chamber

Continuation of the front page (72) Takashi Somune 3903-39, Abundant Town, Himeji City, Hyogo Prefecture 3903-39, Nihon Kayaku Co., Ltd. Himeji Factory Sensor Technology Co., Ltd., Himeji Technical Center (72) Creator Akihiko Kuroiwa Himeji, Hyogo Prefecture 3903-39, Toyotomi-cho, Toyotomi-cho, Nihon Kayaku Co., Ltd., Himeji Factory, Sensor Technology Co., Ltd., Himeji Technical Center (72) Inventor, Norihisa Miyamoto 3903-39, Toyotomi-cho, Himeji, Hyogo Nihon Kayaku Co. Inside Sensor Technology Co., Ltd. Himeji Technical Center

Claims (5)

[Scope of utility model registration request] 1. A gas generation formed by abutting and friction-welding inner pipes (2, 5) and outer pipes (3, 6) on the open side of a bottomed double pipe (1, 4). A central space corresponding to the ignition chamber (P) of the agent and an annular space corresponding to the combustion / filter chambers (G, F) that are concentrically formed outside thereof and perform gas combustion, cooling, and slag collection. Among them, in the annular space portion, the gas generating agent (7) is accommodated on the inner side and the cooling / slag collecting member (10) is disposed on the outer side from the axial center side toward the radially outer side. In addition, a fire transfer orifice (2a) that connects the central space portion and the annular space portion with each other.
And a gas discharge orifice (3a) communicating with the annular space and the outside, and a metal foil (14) for closing at least the gas discharge orifice (3a) is attached to the inner surface of the annular space. A chamber-structured gas generator for an air bag, wherein a virtual cylinder formed when the gas discharge orifice (3a) is assumed to be extended with respect to the axial center side, and the cooling / slag collecting member (10). Of the cooling / slag collecting member (10), the cover plate (30) covering the area corresponding to the orifice opening area formed in the inner peripheral surface of the member (10) by the intersection with the inner peripheral surface of A gas generator for an air bag, characterized by being installed on the peripheral surface side. 2. The air according to claim 1, wherein the cover plate is a cylindrical cover ring (31) which entirely covers only an upper side of an inner peripheral surface of the cooling / slag collecting member (10). Gas generator for bags. 3. The cover plate is a tubular body (32, 33, 34) attached along the entire inner peripheral surface of the cooling / slag collecting member (10), and the cover plate is provided below the member. 2. The gas generator for an air bag according to claim 1, wherein the gas passage orifices (32a, 33a, 34a) are formed. 4. The cooling / slag collecting member (10) comprises:
It is formed from a two-layer mesh member of an inner layer portion (40) and an outer layer portion (41) in the radial direction, and the inner layer portion (40) is more than the mesh member arranged in the outer layer portion (41). The gas generator for an air bag according to any one of claims 1 to 3, wherein a mesh member having a coarse mesh is arranged. 5. The gas generating agent (7) is a compound containing an organic compound having a nitrogen atom as a constituent element (hereinafter abbreviated as “nitrogen atom-containing organic compound”) as a main fuel component. Item 5. The gas generator for an airbag according to any one of Items 4.