JP2008239153A - Gas generator for airbag - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an airbag gas generator equipped with an enhanced flowout preventive effect for the slag in the combustion gas. <P>SOLUTION: The outer edge of an annular filter seal member 25 is fitted by pressure into a housing 3. The filter seal member abuts to the bottom of a cooling filter member 7 to seal the bottom. The filter seal member 25 has a folded part 25f folded toward a lower lid 2a at the bore of the cooling filter member 7, and the inner edge end part of the filter seal member 25 installed at the forefront of the folded part 25f abuts to the inside surface of the lower lid 2a to cause the filter seal member 25 to be held inside the housing 3 resiliently. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention is a gas generator used in an air bag safety device for ensuring the safety of an automobile driver and an occupant from an impact caused by an automobile collision accident or the like, and in particular, an effect of preventing slag in combustion gas from flowing out to the outside. The present invention relates to a gas generator for an air bag excellent in quality (hereinafter simply referred to as “gas generator”).

  Some of these types of gas generators have so-called one-cylinder and two-cylinder housing structures. Also, the housing structure includes both a welding type and a friction welding type. For example, a typical example of a gas generator having a single welded housing structure will be described with reference to FIG. 13 (schematic cross-sectional view). The housing 3 of the gas generator has an upper container 1 joined to a lower container 2 and an interior thereof. A one-tube structure having a space S is adopted. Specifically, first, the upper container 1 is a stainless steel molded body composed of an upper lid 1a and a side cylinder 1b depending from the outer peripheral edge of the upper lid 1a. A plurality of gas discharge ports 8 are provided, and a metal foil 9 covering the gas discharge port 8 is attached to the inner wall surface of the side tube 1b to seal the gas generating agent 6. On the other hand, the lower container 2 is composed of a lower lid 2a, a flange cylinder portion 2b that rises upward from the lower lid 2a on the outer diameter side of the side cylinder 1b, and a side flange 2c that is folded horizontally thereafter. This is a molded body made of stainless steel.

  The housing 3 is formed by welding a flange portion 1c formed by bending outward at the lower end of the side tube 1b of the upper container 1 to the inner bottom edge of the lower lid 2a of the lower container 2. Further, in the housing 3, an igniter 4 is fixed to a central portion of the lower lid 2a via a seal 5, and a gas generating agent 6 is loaded around the igniter 4, and further, a layer of the gas generating agent 6 and an upper container. A cooling and / or filter member (hereinafter simply referred to as “cooling / filter member”) 7 is loaded in the space formed by the first container 1 and the lower container 2.

  When such a gas generator is energized in response to a collision signal, the gas generating agent 6 is combusted by the ignition of the igniter 4 to generate high-temperature gas. This high-temperature gas contains a lot of slag, but is cooled while passing through the cooling / filter member 7 and, after most of the slag is removed, an air bag (not shown) from the gas discharge port 8 It is designed to be released inside.

  Next, a typical example of a gas generator having a one-tube friction welding type housing structure will be described with reference to FIG. 14 (schematic cross-sectional view). As compared with the welding type housing structure of FIG. The lower end peripheral surface of the side tube 1b of the upper container 1 is characterized in that it is formed by friction welding to the inner bottom peripheral edge of the lower lid 2a, and the other basic configuration is the same as the example of FIG. is there. Further, the operation of the gas generator having the friction welding type structure is not different from that of the welding type structure. Furthermore, when performing friction welding, there is a situation that it is generally difficult to control the height during pressure welding. In view of this point, for example, of the end surfaces of the cooling / filter member, the end surface closer to the friction welding portion is used. Even if the height adjustment at the time of friction welding is insufficient, a filter seal member that can absorb it is interposed, and the slag in the combustion gas does not flow beyond the allowable amount from the end of the cooling / filter member It is also possible to consider this.

  However, in any of the above types of gas generators, during operation of the gas generator, depending on the type of gas generating agent, combustion conditions, etc., the instantaneous pressure rise of the combustion gas generated in the housing It has been found that the contact state between the end portion of the cooling / filter member and the upper lid, the lower lid or the filter seal member is loosened and the end face seal of the cooling / filter member may be insufficient.

  This invention is made | formed in view of this point, and it aims at providing the high quality gas generator excellent in the external outflow prevention effect of the slag in combustion gas especially.

(1) The gas generator for an air bag of the present invention has a radial direction from the center to the inside of a housing formed by closing the end of a side cylinder having a plurality of gas discharge ports with an upper lid and a lower lid. A gas generator for an air bag in which an igniter, a gas generating agent, a cooling / filter member are sequentially arranged toward the outside, and a metal foil that covers the gas discharge port from the inside is attached to the inner wall surface of the side tube. A ring-shaped filter seal member whose outer edge is press-fitted inside the housing, wherein the filter seal member contacts the lower end of the cooling / filter member to seal the lower end, and the filter seal member Has a bent portion bent toward the lower lid side on the inner diameter side of the cooling / filter member, and an inner edge end portion of the filter seal member provided at a tip of the bent portion is the lower portion. By abutting the inner surface, said filter sealing member within the housing is characterized in that it is held elastically.

  Such elastic holding of the filter seal member prevents the contact between the filter seal member and the cooling / filter member from being loosened due to the generated internal pressure during operation of the gas generator, thereby preventing a gap. That is, even if the filter seal member bends due to the generated internal pressure, the filter seal member can be bent flexibly while maintaining good contact with the cooling / filter member, so that the slag outflow prevention effect can be effectively exhibited. There is no change. In addition, as an additional effect of the elastic holding of the filter seal member, it is possible to absorb the variation in the margin for friction welding, and there is an advantage that the pressure welding work becomes easy.

(2) It is preferable that the bent portion is formed in a hook shape.
(3) It is preferable that the bent portion is formed with a leg portion that makes contact with the inner surface of the lower lid at a right angle.
(4) It is preferable that the cooling / filter member presses the filter seal member downward, and the highest position of the leg portion is located above the lower end of the cooling / filter member.
(5) It is preferable that the filter seal member is fixed by a pressure contact burr by friction welding between the side tube and the lower lid at a portion in contact with the inner peripheral surface of the side tube.

  As a result of the elastic holding as in the invention of (1) above, the contact between the filter seal member and the cooling / filter member is not loosened due to the generated internal pressure during the operation of the gas generator, and no gap is formed. That is, even if the filter seal member bends due to the generated internal pressure, the filter seal member can be bent flexibly while maintaining good contact with the cooling / filter member, so that the slag outflow prevention effect can be effectively exhibited. There is no change. In addition, as an additional effect of the elastic holding of the filter seal member, it is possible to absorb the variation in the margin for friction welding so that there is an advantage that the pressure welding work becomes easy.

According to the inventions of the above (2), (3) and (4), the filter seal member is more strongly applied to the end face of the cooling / filter member due to the action of the vertical upward elastic reaction force generated in the hook-shaped bent portion. It is in a state of being in close contact with each other, and the effect of preventing the outflow of slag becomes more remarkable due to the improvement of the face seal performance.
According to the invention of the above (5), the fixing of the filter seal member in the housing is further strengthened, and further improvement of the surface sealing performance of the cooling / filter member is expected.

  Hereinafter, a reference embodiment (related to FIGS. 1 to 7, 11, and 12) and an embodiment of the present invention (related to FIGS. 8 to 10) will be described with reference to the drawings. FIG. 1 is a schematic cross-sectional view showing a main part of a gas generator having a one-tube friction welding type housing structure. A housing 3 includes a side tube 1b of an aluminum upper container 1 and a step 2b of an aluminum lower container 2. The inner space is formed by butting the tips of each other and friction welding. In the internal space, the igniter 30, the gas generating agent 6 sealed in the thin film container 5, and the cooling / filter member 7 are sequentially arranged from the center toward the radially outer side. The cooling / filter member 7 has a cylindrical shape with a smaller diameter than the side cylinder 1b so as to be accommodated in the side cylinder 1b. In the drawing, the igniter 30 is an integrated squib 31 and transfer charge 32.

  Further, the upper and lower end surfaces of the cooling / filter member 7, that is, between the upper surface of the cooling / filter member 7 and the upper lid and between the lower surface of the cooling / filter member 7 and the upper surface of the lower lid 2a, 10a and 10b are arranged so that the combustion gas does not flow out to the outside while containing slag. In addition, an aluminum foil 9 is adhered and sealed to the inner surface of the gas discharge port 8 so that the combustion pressure can be adjusted, and the gas generating agent 6 is prevented from being altered. . Further, ring-shaped first and second bypass prevention members 15 and 16 having an L-shaped cross section are disposed in contact with the inner surfaces of the upper and lower ends of the cooling / filter member 7 and also in contact with the inner surfaces of the upper lid 1a and the lower lid 2a. ing. The first and second bypass prevention members 15 and 16 are press-fitted into the cooling / filter member 7.

  With such a configuration, even if a high pressure due to combustion gas is instantaneously generated in the housing 3 during operation of the gas generator, the bypass preventing members 15 and 16 disposed on the inner surfaces of both ends of the cooling / filter member 7. Since this is in a state where it is strongly pressed against both ends of the cooling / filter member 7, it acts rather to improve the end face seal. Therefore, by employing the bypass prevention members 15 and 16 according to the present invention, there is room for omitting one or both of the seal members 10a and 10b, and there is a possibility of cost reduction by reducing the number of parts. On the other hand, by using the bypass prevention members 15 and 16 together, it is possible to ensure the slag outflow prevention effect by the graphite sealing members 10a and 10b.

  FIG. 2 shows a projection when the gas discharge port 8 is projected toward the inner surface of the cooling / filter member 7 of the first bypass prevention member 15 on the side of the upper lid 1a in FIG. The structural example arrange | positioned so that an area part (A) may be covered is shown. The first bypass prevention member 15 has a cover portion 15c that is extended at a portion in contact with the cooling / filter member 7 and covers the projection area portion (A). In the case of this gas generator, as in the case of the gas generator of FIG. 1, not only can an excellent slag outflow prevention effect be enjoyed, but the portion closest to the gas discharge port 8 of the cooling / filter member 7 is bypassed. Since it is blocked by the prevention member 15, it is possible to prevent the generated high-temperature combustion gas from concentrating and flowing out to the projected area portion A of the cooling / filter member 7 and its vicinity. That is, it is possible to equalize the gas flow of the cooling / filter member 7 and prevent local melting of the member.

  In addition, as a structure which arrange | positions the bypass prevention member 15 by the side of the upper cover 1a so that the projection area part (A) when the gas discharge port 8 is projected toward the inner surface of the cooling / filter member 7 may be covered. As shown in FIG. 3, the cover portion 15 c may be arranged slightly away from the inner surface of the cooling / filter member 7 in a portion corresponding to the range covering the projected area portion (A). In this case, it is possible to eliminate the dead space of the cooling / filter member that has occurred due to the attachment of the bypass prevention member 15, and the use efficiency of the cooling / filter member 7 can be increased accordingly. It becomes.

  FIG. 4 shows a configuration example in which the space S1 is formed between the outer peripheral surface of the cylindrical cooling / filter member 7 and the gas discharge port 8 in the gas generator shown in FIG. The cylindrical cooling / filter member has an outer peripheral diameter that is predetermined from an inner peripheral diameter of the side cylinder 1b so as to form a predetermined space S1 between the outer peripheral surface and the inner peripheral surface of the side cylinder 1b. The size of is small. The height is shorter than the distance between the upper lid 1a and the lower lid 2a by a predetermined length. In this gas generator, the space S1 becomes a gas reservoir and the outlet side of the cooling / filter member is equalized. As a result, the influence of the gas flow restriction effect by the gas discharge port 8 is reduced, and the combustion gas is cooled and It passes through most of the volume of the filter member 7. Therefore, in particular, the sealing effect of the bypass preventing members 15 and 16 against the gas flow flowing through both ends of the cooling / filter member 7 becomes more valuable.

  The characteristic configuration of the gas generator shown in FIG. 5 is that the cooling / filter member 7 is disposed in contact with the filter guide 1c and the pressure burrs 12a and 12b of the upper lid 1a. The side cylinder 1b and the upper lid 1a are integrated, the side cylinder 1b and the lower lid 2a are joined by friction welding to form a housing 3, and pressure welding burrs 12a and 12b by this friction welding are formed. A thick filter guide 1c formed from the inner peripheral surface of the side tube 1b in the vicinity of the upper lid 1a toward the outer peripheral surface of the cooling / filter member 7 is in contact with the outer peripheral surface of the cooling / filter member 7. A predetermined space S1 is formed. With this configuration, the space S1 can be reliably formed between the outer peripheral surface of the cooling / filter member 7 and the gas discharge port 8 and can be stably secured.

  Next, FIG. 6 shows a housing 33 having a central cylinder 40 connecting the upper lid 1a and the lower lid 2a around the igniter 30, and a gas having a so-called two-cylinder friction welding type housing structure. Generator. That is, the housing 33 is strengthened by the presence of the central tube 40 formed by butt friction welding between the inner side tube 1d of the upper container 1 and the inner stepped portion 2d of the lower container 2, and the housing 33 is accordingly expanded when the gas generating agent 6 is burned. It becomes difficult to deform | transform, and the slag outflow prevention effect by the bypass prevention members 15 and 16 which concerns on this invention becomes still more effective. In the figure, reference numeral 17 denotes a cover member for the gas generating agent.

  Next, the characteristic configuration of the gas generator shown in FIG. 7 is that the bypass prevention member 16 and the gas generating agent cover member on the lower lid 2a side are integrated in the configuration of the gas generator shown in FIG. It is in the point comprised with the made member. That is, the surface contacting the lower lid 2a of the lower bypass prevention member 16 having an L-shaped cross section is extended inward, and is further integrated so as to come into contact with the pressure contact burr 11a on the outer surface of the central cylinder 40 and the filter seal member 25. It is a thing. Such a filter seal member 25 has a ring shape, and the cross section thereof includes a first straight portion 50a in contact with the inner peripheral surface on the lower end side of the cooling / filter member 7, and the first linear portion 50a, as shown in FIG. A first straight line portion 50a connected to one end side of the lower lid 2a, the second straight line portion 50b contacting the inner surface of the lower lid 2a, a rising portion 50c rising from the other end of the second straight line portion 50b toward the upper lid 1a; An overhanging portion 50 d that protrudes from the upper end of the portion 50 c toward the outer peripheral surface of the central cylinder 40 is provided. The tip of the overhang 50 d is provided with a folded portion along the outer peripheral surface of the central cylinder 40 in order to facilitate the insertion of the filter seal member 25 into the central cylinder 40. Such a filter seal member 25 is press-fitted into the outer peripheral surface of the central cylinder 40.

  With this configuration, a separate cushioning material is required so far to protect the gas generating agent 6 from the hot press burr 11a of the central cylinder 40 and prevent powdering due to vibration of the gas generating agent 6 or the like. In the two-cylinder housing structure that has been assumed, the filter seal member 25 according to the present invention can perform the role that these members have played, at the same time. Therefore, it can be expected to bring about an effect of reducing the number of parts and contribute to cost reduction. In addition to the effect of preventing slag outflow, the filter seal member 25 can also serve to position the cooling / filter member 7 in the two-cylinder housing structure, and the cooling / filter member can be more easily fixed. We can expect the effect to become. In order to equalize the gas flow of the cooling / filter member 7, the first bypass prevention member 15 or the filter seal member 25 may be provided with a cover portion that covers the gas discharge port. Alternatively, a predetermined space may be formed between the inner peripheral surface of the side tube 1 b and the outer peripheral surface of the cooling / filter member 7.

<First Embodiment>
Next, FIG. 8 is a schematic cross-sectional view of an essential part showing a gas generator having a one-tube friction welding type housing structure as in FIGS. 1 to 7, and one of the structural features is shown in FIGS. In FIG. 7, instead of the presence of the bypass prevention members 15 and 16 which are arranged in contact with the inner surfaces of both ends of the cooling / filter member 7 and the inner surfaces of the upper lid 1a and the lower lid 2a, the end portions of the cooling / filter member 7 are For sealing, the filter seal member 25 press-fitted into the housing 3 is bent toward the lower lid 2 a on the inner diameter side of the cooling / filter member 7 and comes into contact with the lower lid 2 a, so that the filter seal member 25 is moved inside the housing 3. It is in the point of being held elastically.

  As shown in FIG. 8, the filter seal member 25 has a ring shape. As shown in FIG. 8, the linear portion 25b that supports the lower end of the cooling / filter member 7, and from one end side of the linear portion 25b to the upper lid 1a side. A rising portion 25e rising upward, an overhang portion 25a protruding from the upper end of the rising portion 25e toward the inner peripheral surface of the side tube 1b, and the other end side of the linear portion 25b toward the inner surface of the lower lid 2a. It has a bent portion 25f that is bent and contacts the inner surface of the lower lid 2a. The tip of the overhanging portion 25a is provided with a folded portion along the inner peripheral surface of the side tube 1b in order to facilitate the insertion of the filter seal member 25 into the side tube 1b. Such a filter seal member 25 is elastically held in the side tube 1b by the protruding portion 25a and the bent portion 25f coming into contact with the inner peripheral surface of the side tube 1b and the inner surface of the lower lid 2a, respectively. . And such a filter seal member 25 is press-fitted with respect to the internal peripheral surface of the said side cylinder 1b.

  In the case of the gas generator having such a structure, even if the filter seal member 25 is bent by the generated internal pressure during the operation of the gas generator due to the elastic holding of the filter seal member 25 in the housing 3, the cooling is performed. As a result of bending integrally while maintaining a good contact state with the filter member 7, the contact state with the upper lid 1a or the filter seal member 25 at the end of the cooling / filter member 7 is loosened and a gap is generated. Since a good face seal is maintained, the same slag outflow prevention effect as that of the gas generator employing the bypass prevention members 15 and 16 can be exhibited. Further, according to the configuration of the present example, as an additional effect of elastic holding of the filter seal member 25, it is possible to absorb the variation in the margin of deviation during friction welding, and therefore, there is an advantage that the pressure welding work becomes easy. is there.

  In addition, as another structural feature of the illustrated gas generator, the filter seal member 25 is press-fitted into the housing 3 and the press-fitted portion 25a is held and fixed by the pressure contact burr 12a. It is in. As a result, the fixing of the filter seal member 25 in the housing is further strengthened, so that further improvement in the surface sealing performance of the cooling / filter member is expected.

Second Embodiment
FIG. 9 shows a hook 25 having a portion 25c bent to the lower lid side on the inner diameter side of the cooling / filter member 7 in the filter seal member 25 in the configuration of the gas generator shown in FIG. The example of what arrange | positioned so that the front-end | tip of 25c is contact | abutted to the lower cover 2a and the filter seal member 25 is elastically hold | maintained within a housing is shown. The shape of the bent hook portion 25c on the inner diameter side of the filter seal member 25 is such that the highest position of the leg portion 25d is at the lower end of the cooling / filter member 7 before the gas generator is assembled, as shown in FIG. After the assembly, as shown in FIG. 5B, the leg 25d is pushed upward so that the highest position of the leg 25d is located above the lower end of the cooling / filter member 7. It is configured. Therefore, in the gas generator after assembling, the filter seal member 25 is more closely attached to the end surface of the cooling / filter member 7 due to the action of the vertical upward elastic reaction force generated at the hook-shaped bent portion. The slag outflow prevention effect becomes even more remarkable due to the improvement of the face seal performance.

  In the embodiment shown in FIGS. 8 and 9, the first bypass prevention member 15 may be provided on the upper lid 1a side. Further, in order to equalize the gas flow of the cooling / filter member 7, a cover portion that covers the gas discharge port may be provided in the first bypass prevention member 15. Alternatively, a predetermined space may be formed between the inner peripheral surface of the side tube 1 b and the outer peripheral surface of the cooling / filter member 7. The housing of the gas generator may have a central cylinder at the center.

  FIG. 11 is a gas generator having a two-cylinder friction welding type housing structure similar to FIGS. 6 and 7, and there is no difference in configuration except that a filter seal member 26 is employed as a bypass prevention member. In particular, it can be said to correspond to FIG. That is, the characteristic configuration of the gas generator shown in FIG. 11 is that the filter seal member 26 is integrated with the filter seal member 25 on the lower lid 2a side in FIG. 8 and the gas generating agent cover member 17 in FIG. It is in the point comprised with the member. In other words, the filter seal member 26 extends toward the inner diameter side along the lower lid 2a, and the inside of the extending portion rises and is press-fitted into the outer surface of the central cylinder 40. Further, the bent portion 26a is formed by cutting into a portion extending along the lower lid 2a, but as shown in FIG. 12 (a cross-sectional view taken along the arrow BB in FIG. 11), A bent portion may be formed at an appropriate interval.

  The filter seal member 26 has a ring shape, and its cross section rises toward the upper lid 1a from both ends of the linear portion 26c parallel to the inner surface of the lower lid 2a and both ends of the linear portion 26c, as shown in FIG. Rising portions 26d, 26e, and projecting portions 26f, 26g projecting from the upper ends of the rising portions 26d, 26e toward the inner peripheral surface of the side tube 1b and the outer peripheral surface of the central tube 40, respectively. And has a substantially clamp shape. The tip of the overhang portion 26f is provided with a folded portion along the inner peripheral surface of the side tube 1b in order to facilitate the insertion of the filter seal member 26 into the side tube 1b. On the other hand, a folded portion is also provided along the outer peripheral surface of the central cylinder 40 in order to facilitate the insertion of the filter seal member 26 into the central cylinder 40 at the tip of the overhanging portion 26g. The straight portion 26c supports the lower end of the cooling / filter member 7 and covers the gas generating agent storage space from the lower lid 2a side. The straight portion 26c is formed with the bent portion 26a which is cut as described above and is in contact with the inner surface of the lower lid 2a. Such a filter seal member 26 is elastic because the projecting portions 26f and 26g and the bent portion 26a are in contact with the inner peripheral surface of the side tube 1b, the outer peripheral surface of the central tube 40, and the inner surface of the lower lid 2a, respectively. Is housed in the side tube 1b. Such a filter seal member 26 is press-fitted into the outer peripheral surface of the central cylinder 40.

  In the case of the illustrated gas generator, the cost can be reduced by reducing the number of parts as in the case of the gas generator of FIG. 7, and the high-pressure gas generated during the operation of the gas generator is the bent portion. 26a flows into the lower lid 2a side through the opening 26b around the periphery of the filter 26a, and wraps around the back side of the filter seal member 26. Therefore, the front and back of the filter seal member 26 have the same pressure, and even elastic deformation of the filter seal member 26 is suppressed. be able to. Therefore, it is possible to provide a gas generator having a two-cylinder structure with an excellent slag outflow prevention effect by ensuring the face seal performance at the end of the cooling / filter member 7. Also in the example shown in FIG. 11, in order to equalize the gas flow of the cooling / filter member 7, the first bypass prevention member 15 may be provided with a cover portion that covers the gas discharge port. Alternatively, a predetermined space may be formed between the inner peripheral surface of the side tube 1 b and the outer peripheral surface of the cooling / filter member 7.

  In the illustrated example, the friction welding type gas generator is exemplified. However, in the case of a welding type gas generator using a laser or the like, the characteristic configuration of the present invention is the same, and the corresponding operation is performed. There is no particular difference in the effect, and a gas generator excellent in the effect of preventing the outflow of slag in the combustion gas can be obtained.

It is a principal part cross-sectional schematic diagram which shows reference embodiment. It is a figure principal part section schematic diagram showing a reference embodiment of a gas generator characterized by an upper bypass prevention member. It is a principal part cross-sectional schematic diagram which shows the reference modification of the gas generator of FIG. It is a principal part cross-sectional schematic diagram which shows the reference embodiment of the gas generator which has a space part just before a gas discharge port. It is a principal part cross-sectional schematic diagram which shows other reference embodiment. It is a principal part cross-sectional schematic diagram which shows another reference embodiment. It is a principal part cross-sectional schematic diagram which shows another reference embodiment. It is a principal part cross-sectional schematic diagram which shows 1st Embodiment of this invention. It is a principal part cross-sectional schematic diagram which shows 2nd Embodiment of this invention. It is a principal part enlarged view of the filter seal member in 2nd Embodiment of this invention, (a) is a figure before the assembly of a gas generator, (b) is a figure which shows the shape after an assembly. It is a principal part cross-sectional schematic diagram which shows another reference embodiment. It is BB arrow principal part sectional drawing of FIG. 11, and is a partial plane of a filter seal member. It is a cross-sectional schematic diagram which shows the typical example of a 1-tube type welding type housing structure. It is a cross-sectional schematic diagram which shows the typical example of a 1 cylinder type friction welding type housing structure.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Upper container 1a Upper lid 1b Side cylinder 1c Filter guide 1d Inner side cylinder 2 Lower container 2a Lower lid 2b Side cylinder 2d Inner side cylinder 3,33 Housing 5 Thin film container 6 Gas generating agent 7 Cooling / filter member 8 Gas discharge port 9 Metal Foil 10a, 10b Seal member 11a, 12a, 12b Pressure contact burr 15, 16 Bypass prevention member 25, 26 Filter seal member 30 Igniter 31 Squib 32 Transfer powder 40 Central cylinder S1 Space

Claims (5)

The inside of the housing (3) formed by closing the end of the side cylinder (1b) having a plurality of gas discharge ports (8) with the upper lid (1a) and the lower lid (2a) has a diameter from the center. An igniter (30), a gas generating agent (6), and a cooling / filter member (7) are sequentially arranged toward the outside in the direction, and a metal foil (9) covering the gas discharge port (8) from the inside is provided. A gas generator for an airbag that is adhered to the inner wall surface of the side tube (1b),
A ring-shaped filter seal member (25) whose outer edge is press-fitted inside the housing (3);
The filter seal member (25) contacts the lower end of the cooling / filter member (7) to seal the lower end,
The filter seal member (25) has a bent portion (25f, 25c) bent toward the lower lid (2a) on the inner diameter side of the cooling / filter member (7), and the bent portion (25f, 25c) The filter seal member (25) is elastically held in the housing (3) by the inner edge of the filter seal member (25) provided at the tip contacting the inner surface of the lower lid (2a). A gas generator for an air bag, wherein   The gas generator for an air bag according to claim 1, wherein the bent portion (25c) is formed in a hook shape.   The gas generator for an airbag according to claim 2, wherein the bent portion (25c) is formed with a leg portion (25d) that makes contact with the inner surface of the lower lid (2a) at a right angle.   The cooling / filter member (7) presses the filter seal member (25) downward, and the highest position of the leg (25d) is located above the lower end of the cooling / filter member (7). The gas generator for an air bag according to claim 3.   The filter seal member (25) is fixed by a pressure contact burr (12a) by friction welding between the side tube (1b) and the lower lid (2a) at a portion in contact with the inner peripheral surface of the side tube (1b). The gas generator for an air bag according to any one of claims 1 to 4.

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