Gas generator

Abstract

A gas generator is provided that improves the efficiency of filter utilization and facilitates manufacturing. [Solution] The gas generator (1A) comprises a housing including a peripheral wall portion (11), a partition member (50), and an igniter (40). The housing contains a gas generating agent storage chamber (S1) and a filter chamber (S2) in which a filter (80) is disposed. The filter (80) comprises a cylindrical portion (81) extending substantially parallel to the axial direction of the housing, and a skirt portion (82) extending continuously from at least one of a pair of ends of the cylindrical portion (81) and sloping or curved so as to approach the peripheral wall portion (11) as it moves away from the cylindrical portion (81), and these are provided with a flow passage portion (83). The inclusion of the skirt portion (82) in the filter (80) separates the cylindrical portion (81) from the peripheral wall portion (11), thereby providing a gap portion (84) therebetween. The gas outlet (12) is provided in at least a portion of the peripheral wall portion (11) that faces the filter (80) but does not abut against the filter (80).

Description

[Technical Field]

[0001] The present invention relates to a gas generator to be incorporated into an airbag device as an occupant protection device equipped in an automobile or the like, and particularly to a so-called cylinder-type gas generator having an elongated cylindrical outer shape that is suitably incorporated into a side airbag device or the like. [Background technology]

[0002] Airbag devices, which are passenger protection devices, have become widespread from the viewpoint of protecting passengers in automobiles, etc. Airbag devices are installed to protect passengers from impacts that occur during a vehicle collision, and the airbag instantly inflates and deploys during a vehicle collision, thereby acting as a cushion to support the passenger's body.

[0003] The gas generator is incorporated into this airbag device. When a vehicle crashes, the control unit energizes the igniter, which then generates a flame that burns the gas generating agent, instantly generating a large amount of gas, which inflates and deploys the airbag.

[0004] There are gas generators of various configurations based on specifications such as the installation position relative to a vehicle, etc., and gas output. One of these is what is called a cylinder-type gas generator. A cylinder-type gas generator has an elongated cylindrical outer shape and is suitably incorporated into a side airbag device, a curtain airbag device, a knee airbag device, a seat cushion airbag device, etc.

[0005] Typically, in a cylinder-type gas generator, an igniter is assembled to one axial end of a housing, a gas generating agent storage chamber is provided at the one end, and a filter chamber is provided at the other axial end of the housing. A gas outlet is provided in a peripheral wall of the housing at a portion that defines the filter chamber.

[0006] In a cylinder-shaped gas generator configured in this manner, gas generated in the gas generating agent storage chamber flows into the filter chamber along the axial direction of the housing, passes through the inside of the filter, and the gas that has passed through the filter is ejected to the outside via the gas ejection port. Literature that discloses such a cylinder-shaped gas generator includes, for example, Japanese Patent Application Laid-Open No. 2016-68891 (Patent Document 1).

[0007] In the cylinder-shaped gas generator disclosed in Patent Document 1, a folded-back portion is provided at the end of the filter, thereby providing a gap between the portion of the filter other than the folded-back portion and the peripheral wall portion of the housing. This allows gas that has flowed into the filter chamber to pass through the portion of the filter that corresponds to the gap, resulting in improved filter utilization efficiency. [Prior art documents] [Patent documents]

[0008] [Patent Document 1] Japanese Patent Application Laid-Open No. 2016-68891 Summary of the Invention [Problem to be solved by the invention]

[0009] Here, in the cylindrical gas generator configured as described above, since no hole is provided in the folded-back portion, gas does not flow through the folded-back portion, and there is room for improvement in terms of improving the utilization efficiency of the filter. Furthermore, providing a folded-back portion as described above at the end of the filter significantly complicates the filter manufacturing work, which in turn makes manufacturing the gas generator difficult.

[0010] Therefore, the present invention has been made in consideration of the above-mentioned problems, and has an object to provide a gas generator in which the utilization efficiency of the filter is improved and the manufacturing method is simplified. [Means for solving the problem]

[0011] A gas generator according to the present invention includes a housing, a partition member, and an igniter. The housing has a cylindrical peripheral wall portion provided with a gas outlet. One and other axial ends of the housing are closed, and the housing includes a gas generating agent storage chamber containing a gas generating agent and a filter chamber in which a filter is disposed. The partition member divides the interior space of the housing in the axial direction so that the gas generating agent storage chamber is located at the one end and the filter chamber is located at the other end. The igniter is assembled to the one end of the housing. The filter has a cylindrical portion and a skirt portion. The cylindrical portion extends along a direction substantially parallel to the axial direction. The skirt portion extends continuously from at least one of a pair of axial ends of the cylindrical portion, and is inclined or curved so as to approach the peripheral wall portion as it moves away from the cylindrical portion. The cylindrical portion and the skirt portion are provided with flow passages through which gas can pass. Since the filter has the skirt portion, the cylindrical portion is positioned apart from the peripheral wall portion, thereby providing a gap between the cylindrical portion and the peripheral wall portion. In the gas generator based on the present invention, the gas outlet is provided at least in a portion of the peripheral wall portion that faces the filter but does not abut against the filter.

[0012] In the gas generator based on the present invention, the skirt portion may include a first skirt portion provided at an end portion on the one end side of the pair of ends located in the axial direction of the cylindrical portion. In this case, an axial end face of the first skirt portion may abut against the partition member.

[0013] In the gas generator based on the present invention, the housing may have a closing portion that closes the other end. In that case, the skirt portion may include a second skirt portion provided at the end of the pair of axial ends of the cylindrical portion that is closer to the other end. Also, in that case, an axial end face of the second skirt portion may abut against the closing portion.

[0014] In the gas generator according to the present invention, at least a portion of the skirt portion in the circumferential direction may be in contact with the peripheral wall portion.

[0015] In the gas generator according to the present invention, the entire portion of the skirt portion in the circumferential direction may be in contact with the peripheral wall portion. [Effects of the Invention]

[0016] According to the present invention, it is possible to provide a gas generator in which the utilization efficiency of the filter is improved and the manufacturing process is simplified. [Brief explanation of the drawings]

[0017] [Figure 1] 1 is a schematic view of a cylinder-shaped gas generator according to an embodiment. [Figure 2] FIG. 2 is an enlarged view of the vicinity of the igniter shown in FIG. [Figure 3] FIG. 2 is an enlarged view of the vicinity of the partition member shown in FIG. [Figure 4] FIG. 2 is a schematic cross-sectional view of the cylinder-shaped gas generator shown in FIG. [Figure 5] FIG. 2 is a schematic cross-sectional view of the cylinder-shaped gas generator shown in FIG. [Figure 6] FIG. 2 is an enlarged perspective view of a surface portion of the filter shown in FIG. [Figure 7] 2A to 2C are schematic diagrams for explaining a method for manufacturing the filter shown in FIG. [Figure 8] 2A to 2C are schematic diagrams for explaining a method for manufacturing the filter shown in FIG. [Figure 9] 5A and 5B are schematic cross-sectional views for explaining a method of assembling the filter to the housing. [Figure 10] 5A and 5B are schematic cross-sectional views for explaining a method of assembling the filter to the housing. [Figure 11] FIG. 4 is a schematic view of a cylinder-shaped gas generator according to a comparative example in a first state. [Figure 12] FIG. 10 is a schematic view of a cylinder-shaped gas generator according to a comparative example in a second state. [Figure 13] It is a schematic cross-sectional view of a cylinder-type gas generator shown in FIG. 12. [Figure 14] It is an enlarged perspective view of the surface portion of a filter having a different form from the filter shown in FIG. 6. [Figure 15] It is an enlarged perspective view of the surface portion of a filter having a different form from the filter shown in FIG. 6. [Figure 16] It is a schematic view of the cylinder-type gas generator according to the first modification in the third state. [Figure 17] It is a schematic view of the cylinder-type gas generator according to the first modification in the fourth state. [Figure 18] It is a schematic cross-sectional view of a cylinder-type gas generator shown in FIG. 17. [Figure 19] It is a schematic view of the cylinder-type gas generator according to the second modification. [Figure 20] It is a schematic view of the cylinder-type gas generator according to the third modification.

Mode for Carrying Out the Invention

[0018] Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. The following embodiments illustrate the case where the present invention is applied to a cylinder-type gas generator incorporated in a side airbag device. In the following embodiments, the same or common parts are denoted by the same reference numerals in the drawings, and the description thereof will not be repeated

[0019] (Embodiment) <A. Configuration of Cylinder-Type Gas Generator> FIG. 1 is a schematic view of a cylinder-type gas generator according to an embodiment. FIG. 2 is an enlarged view of the vicinity of the igniter shown in FIG. 1. FIG. 3 is an enlarged view of the vicinity of the partition member shown in FIG. 1. FIG. 4 is a schematic cross-sectional view taken along line IV-IV in FIG. 1. FIG. 5 is a schematic cross-sectional view taken along line V-V in FIG. 1. First, referring to FIGS. 1 to 5, the configuration of the cylinder-type gas generator 1A according to the present embodiment will be described.

[0020] As shown in Figures 1 to 5, cylinder-shaped gas generator 1A has a long, columnar outer shape. Cylinder-shaped gas generator 1A has a long, substantially cylindrical housing whose one axial end and the other axial end are closed. The housing includes housing main body 10, holder 20, closing member 30 as a closing portion, and partition member 50. The outer shell of the housing is defined by housing main body 10, holder 20, and closing member 30.

[0021] The housing main body 10, holder 20 and blocking member 30 contain internal components such as an igniter 40, a plurality of granular gas generating agents 60 (hereinafter also referred to simply as "gas generating agents 60"), an auto-ignition agent 61, a coil spring 70 and a filter 80, and in addition to these, the above-mentioned partition member 50, which is also an internal component, is also arranged.

[0022] The partition member 50 divides the space inside the housing in the axial direction. As a result, inside the housing, a gas generating agent storage chamber S1 is provided at one end side of the housing, and a filter chamber S2 is provided at the other end side of the housing. The gas generating agent storage chamber S1 accommodates the gas generating agent 60, autoignition agent 61, and coil spring 70, which are among the internal components described above. The filter chamber S2 accommodates a filter 80.

[0023] The housing main body 10 constitutes a peripheral wall portion 11 of the housing. The peripheral wall portion 11 is made of a long cylindrical member including a pair of open ends. The peripheral wall portion 11 at one end of the housing in the axial direction defines a gas generating agent storage chamber S1. The peripheral wall portion 11 at the other end of the housing in the axial direction defines a filter chamber S2.

[0024] The housing body 10 may be made of a metal member such as stainless steel, iron steel, aluminum alloy, or stainless alloy, or may be made of a press-formed product formed into a cylindrical shape by pressing a rolled steel plate such as SPCE.The housing body 10 may also be made of an electric resistance welded pipe such as STKM.

[0025] In particular, when the housing body 10 is constructed from a press-formed rolled steel plate or an electric resistance welded pipe, the housing body 10 can be formed more cheaply and easily than when metal components such as stainless steel or steel are used, and the weight can be significantly reduced.

[0026] The holder 20 and the closing member 30 are made of metal members such as stainless steel, iron steel, aluminum alloy, stainless alloy, or the like.

[0027] 1 and 2, holder 20 is made of a substantially cylindrical member having a through-hole 21 extending in a direction parallel to the axial direction of peripheral wall 11, and is assembled to peripheral wall 11 so as to close one of a pair of open ends of peripheral wall 11. In detail, holder 20 is fixed to peripheral wall 11 by joining holder 20 and peripheral wall 11 at or near their contact portions by, for example, welding, with a portion of holder 20 inserted into the open end of peripheral wall 11.

[0028] As a result, a weld 91 extending circumferentially of the housing is provided at the end of the housing located on the open end side of the peripheral wall 11. The gap between the peripheral wall 11 and the holder 20 is filled with the weld 91. Therefore, the gap is sealed by the weld 91, making it possible to ensure airtightness in that portion. Note that electron beam welding, laser welding, resistance welding, or the like can be suitably used to weld the peripheral wall 11 and the holder 20 together.

[0029] The assembly structure of the holder 20 to the peripheral wall 11 is not limited to the above-described assembly structure, and other assembly structures may be adopted. In that case, airtightness between the peripheral wall 11 and the holder 20 can be ensured by providing an O-ring or the like at an appropriate position.

[0030] 1, the blocking member 30 is made of a substantially disk-shaped member and is assembled to the peripheral wall 11 so as to block one of a pair of open ends of the peripheral wall 11 that is located on the other end side in the axial direction of the housing. In detail, the blocking member 30 is inserted into the open end of the peripheral wall 11 so that one axial end face of the blocking member 30 is abutted against the filter 80, and is fixed to the peripheral wall 11 by joining the flange portion of the blocking member 30 to the peripheral wall 11 at or near the contact portion between them, for example, by welding or the like.

[0031] As a result, a weld 92 extending circumferentially of the housing is provided at the end of the housing located on the open end side of the peripheral wall 11. The gap between the peripheral wall 11 and the closing member 30 is filled with the weld 92. Therefore, the gap is sealed by the weld 92, making it possible to ensure airtightness in that portion. Note that electron beam welding, laser welding, resistance welding, or the like can be suitably used to weld the peripheral wall 11 and the closing member 30 together.

[0032] The assembly structure of the blocking member 30 to the peripheral wall portion 11 is not limited to the assembly structure described above, and other assembly structures may be adopted.

[0033] Furthermore, the peripheral wall portion 11 and the closing member 30 may not be separate bodies, but may be configured as a single member having a cylindrical shape with a bottom. In this case, the portion of the single member having a cylindrical shape with a bottom that defines the bottom corresponds to the closing portion.

[0034] 1 and 2, the igniter 40 is mounted to one axial end of the housing by being supported by a holder 20. The igniter 40 is for burning the gas generating agent 60, and is disposed so as to face the space inside the housing.

[0035] The igniter 40 has an ignition section 41 and a pair of terminal pins 42. The ignition section 41 includes a squib cup. A resistor (bridge wire) is attached inside the squib cup so as to connect to the pair of terminal pins 42. The squib cup is filled with an ignition charge so as to surround or be in contact with the resistor. A transfer charge may be loaded inside the squib cup as needed.

[0036] Resistors typically include nichrome wire or alloys containing platinum and tungsten. Ignition charges typically include ZPP (zirconium-potassium perchlorate), ZWPP (zirconium-tungsten-potassium perchlorate), and lead tricinate. Transfer charges include metal powder / oxidizer compositions such as B / KNO3, B / NaNO3, and Sr(NO3)2, titanium hydride / potassium perchlorate, and B / 5-aminotetrazole / potassium nitrate / molybdenum trioxide.

[0037] When a collision is detected, a predetermined amount of current flows through the resistor via the terminal pin 42. This generates Joule heat in the resistor, causing the ignition charge to start burning. The high-temperature particles generated by the combustion split open the squib cup containing the ignition charge. The time from when the current flows through the resistor to when the igniter 40 is activated is generally less than 2 milliseconds if the resistor uses nichrome wire.

[0038] Igniter 40 is fixed to holder 20 by crimping portion 22 provided on holder 20. More specifically, holder 20 has crimping portion 22, for crimping and fixing igniter 40, at an axial end portion facing the interior space of the housing. Igniter 40 is inserted into through portion 21 and is fixed against the wall portion that defines through portion 21, and crimping portion 22 is crimped, whereby igniter 40 is clamped and fixed within holder 20.

[0039] As a result, igniter 40 is assembled to holder 20 so that ignition portion 41 is positioned to protrude toward the inside of the housing. Therefore, when igniter 40 is activated, the ignition charge is ignited, causing the squib cup to split, and the squib cup opens as a result of this splitting.

[0040] A seal member 43 made of an O-ring or the like is interposed between holder 20 and igniter 40. The gap between holder 20 and igniter 40 is filled with seal member 43, thereby sealing the gap. This configuration makes it possible to ensure airtightness in that portion. Note that the assembly structure of igniter 40 is not limited to the assembly structure using crimped portion 22 described above, and other assembly structures may be adopted.

[0041] A recess 23 is provided at the axial end of holder 20 that is exposed to the outside, continuing from the above-mentioned through-hole 21. Recess 23 forms a female connector portion that receives a male connector (not shown) of a harness for connecting igniter 40 to a control unit (not shown). Terminal pin 42 of igniter 40 is positioned exposed within recess 23. The male connector is inserted into recess 23, which serves as the female connector portion. This establishes electrical continuity between the core wire of the harness and terminal pin 42.

[0042] 1 and 3, a partition member 50 is disposed at a predetermined position in the space inside the housing. The partition member 50 is a member for dividing the space inside the housing in the axial direction of the housing so that the gas generating agent storage chamber S1 is located on one axial end side of the housing and the filter chamber S2 is located on the other axial end side of the housing.

[0043] The partition member 50 has a cylindrical shape with a bottom, and is made of a metal member such as stainless steel, iron steel, aluminum alloy, or stainless alloy.

[0044] The partition member 50 has a substantially cylindrical plate-shaped annular wall portion 51 extending along the inner circumferential surface of the peripheral wall portion 11, and a substantially flat plate-shaped partition portion 52 closing one axial end of the annular wall portion 51. The annular wall portion 51 stands from the periphery of the partition portion 52 toward the gas generating agent storage chamber S1. The partition member 50 is arranged so that the main surface of the partition portion 52 facing the filter chamber S2 abuts against a first skirt portion 82a of the filter 80. The first skirt portion 82a will be described later.

[0045] Scores 52a are provided on the main surface of the partition wall portion 52 that comes into contact with the filter 80. The scores 52a are intended to allow the partition wall portion 52 to break and form an opening as the internal pressure of the gas generating agent storage chamber S1 increases due to combustion of the gas generating agent 60, and are configured, for example, by a plurality of grooves that are provided radially so as to intersect with one another. The scores 52a are provided, for example, in a portion of the partition wall portion 52 that is radially inward of a portion that comes into contact with the first skirt portion 82a of the filter 80.

[0046] The partition member 50 is assembled by being inserted into the peripheral wall portion 11 and then joined to the peripheral wall portion 11. More specifically, the partition member 50 is press-fitted into the interior of the peripheral wall portion 11, and is fixed to the peripheral wall portion 11 by joining the annular wall portion 51 of the partition member 50 to the peripheral wall portion 11 at or near the contact portion between them, for example, by welding.

[0047] As a result, a weld 93 extending along the circumferential direction of the housing is provided in the portion of the housing corresponding to the portion into which the partition member 50 is inserted. The gap between the peripheral wall 11 and the partition member 50 is filled with the weld 93. Therefore, the gap is sealed by the weld 93, making it possible to ensure airtightness in that portion. Note that electron beam welding, laser welding, resistance welding, or the like can be suitably used to weld the peripheral wall 11 and the partition member 50 together.

[0048] The assembly structure of the partition member 50 to the peripheral wall portion 11 is not limited to the assembly structure using press-fitting and welding described above, and other assembly structures may be adopted. In that case, airtightness between the peripheral wall portion 11 and the partition member 50 can be ensured by providing an O-ring or the like at an appropriate position.

[0049] Within the space inside the housing, a plurality of granular gas generating agents 60, an autoignition agent 61, and a coil spring 70 are arranged in the space sandwiched between the holder 20 and the partition member 50 (i.e., the gas generating agent storage chamber S1).

[0050] A plurality of granular gas generating agents 60 are arranged on the side of the gas generating agent storage chamber S1 where the holder 20 and the igniter 40 are located. The autoignition agent 61 is arranged so as to abut against the main surface of the partition wall portion 52 on the side facing the gas generating agent storage chamber S1. The coil spring 70 is arranged between the gas generating agents 60 and the autoignition agent 61.

[0051] The gas generating agent 60 is an agent that generates gas by being ignited by hot particles generated by the activation of the igniter 40 and burning. A non-azide gas generating agent is preferably used as the gas generating agent 60. The gas generating agent 60 is generally configured as a molded body containing fuel, an oxidizer, and an additive.

[0052] The fuel may be, for example, a triazole derivative, a tetrazole derivative, a guanidine derivative, an azodicarbonamide derivative, a hydrazine derivative, or a combination thereof. In particular, nitroguanidine, guanidine nitrate, cyanoguanidine, 5-aminotetrazole, or the like is preferably used.

[0053] Examples of oxidizing agents include basic metal salts such as basic copper nitrate and basic copper carbonate, perchlorates such as ammonium perchlorate and potassium perchlorate, and nitrates containing cations selected from alkali metals, alkaline earth metals, transition metals, and ammonia. Suitable nitrates include sodium nitrate and potassium nitrate.

[0054] Examples of additives include binders, slag formers, and combustion adjusters. Suitable binders include organic binders such as metal salts of carboxymethyl cellulose and stearates, and inorganic binders such as synthetic hydrotalcite and acid clay. Suitable slag formers include silicon nitride, silica, and acid clay. Suitable combustion adjusters include metal oxides, ferrosilicon, activated carbon, and graphite.

[0055] The shape of the molded body of the gas generating agent 60 may be various, including granular, pellet-like, cylindrical, or other granular shapes, as well as disk-like shapes. For cylindrical molded bodies, perforated molded bodies having through holes inside the molded body (for example, a single-hole cylindrical shape or a multi-hole cylindrical shape) are also used. These shapes are preferably selected appropriately depending on the specifications of the airbag device into which the cylindrical gas generator 1A is to be incorporated, and it is preferable to select the optimal shape depending on the specifications, such as a shape in which the rate of gas generation changes over time when the gas generating agent 60 is burned. In addition to the shape of the gas generating agent 60, it is preferable to select the size and filling amount of the molded body appropriately taking into consideration the linear burning velocity, pressure exponent, etc. of the gas generating agent 60.

[0056] The coil spring 70 is provided for the purpose of preventing the gas generating agent 60, which is made of a molded body, from being crushed by vibration, etc., and has a spring portion 71 formed by bending a metal wire and a pair of pressing portions 72 located at both ends of the spring portion 71.

[0057] The spring portion 71 is composed of a substantially cylindrical portion around which a metal wire is wound in a spiral shape. One of the pair of pressing portions 72 is provided at one end of the spring portion 71, and the other is provided at the other end of the spring portion 71. The pair of pressing portions 72 is configured to have a substantially disk-like shape as a whole, for example, by arranging the metal wires substantially parallel to each other at a predetermined interval, or by arranging the metal wires in a spiral shape at a predetermined interval. One of the pair of pressing portions 72 is in contact with the gas generating agent 60, and the other of the pair of pressing portions 72 is in contact with the auto-ignition agent 61.

[0058] The coil spring 70 is sandwiched between the autoignition agent 61 and the gas generating agent 60, and is thereby compressed. Therefore, the gas generating agent 60 is elastically biased toward the holder 20 by the coil spring 70, thereby preventing the gas generating agent 60 from moving inside the gas generating agent storage chamber S1. With this configuration, the gas generating agent 60 made of a molded body can be prevented from being crushed by vibration or the like.

[0059] Furthermore, when assembling the coil spring 70, the coil spring 70 is sandwiched and compressed between the auto-ignition agent 61 and the gas generating agent 60, which allows the coil spring 70 to absorb dimensional variations in the various components housed inside the housing.

[0060] The autoignition agent 61 is made of pellets formed into a flat, generally cylindrical shape. The autoignition agent 61 is arranged on the opposite side of the coil spring 70 from the side on which the gas generating agent 60 is located (i.e., on the filter 80 side), and is held by being sandwiched between the bulkhead 52 of the partition member 50 and the coil spring 70. As a result, the autoignition agent 61 is separated from the gas generating agent 60 by the coil spring 70.

[0061] Auto-ignition agent 61 is an agent that ignites automatically without the operation of igniter 40. More specifically, auto-ignition agent 61 spontaneously ignites at a lower temperature than gas generating agent 60, and is intended to prevent abnormal operation of cylinder-shaped gas generator 1A from being induced by external heating in the unlikely event of a fire or the like occurring in a vehicle or the like equipped with an airbag device incorporating cylinder-shaped gas generator 1A.

[0062] As shown in FIG. 1, a filter 80 is disposed in the space within the housing, which is sandwiched between the closing member 30 and the partition member 50 (that is, the filter chamber S2).

[0063] The filter 80 has a tubular portion 81 and a skirt portion 82. The tubular portion 81 extends in a direction substantially parallel to the axial direction of the housing. The skirt portions 82 extend continuously from each of a pair of ends of the tubular portion 81 located in the axial direction, and are inclined so as to approach the peripheral wall portion 11 as they move away from the tubular portion 81. In this embodiment, the tubular portion 81 has a cylindrical shape.

[0064] The skirt portion 82 includes a first skirt portion 82a and a second skirt portion 82b. The first skirt portion 82a is provided at one of a pair of axially extending ends of the cylindrical portion 81 that is closer to one end of the housing (i.e., the end on the partition member 50 side). The second skirt portion 82b is provided at the other of a pair of axially extending ends of the cylindrical portion 81 that is closer to the other end of the housing (i.e., the end on the blocking member 30 side).

[0065] In this embodiment, the first skirt portion 82a and the second skirt portion 82b are positioned at the center of the filter 80 in the axial direction and have shapes that are plane-symmetrical with respect to a plane that is perpendicular to the axial direction.

[0066] A gas-passing flow section 83 is provided in the cylindrical section 81 and the skirt section 82. The filter 80 functions as a cooling means for cooling the gas generated by the combustion of the gas generating agent 60 by removing high-temperature heat contained in the gas when the gas passes through the flow section 83, and also functions as a removal means for removing slag (residue) and the like contained in the gas.

[0067] The method for manufacturing the filter 80 configured as above will be described in detail later.

[0068] 1, 3, and 4, the axial end face of the first skirt portion 82a abuts against the partition wall portion 52 of the partition member 50. The entire circumferential portion of the axial end of the first skirt portion 82a abuts against the peripheral wall portion 11. The axial end face of the second skirt portion 82b abuts against the blocking member 30. The entire circumferential portion of the axial end of the second skirt portion 82b abuts against the peripheral wall portion 11.

[0069] 1 and 5, the filter 80 has a skirt portion 82, so that the cylindrical portion 81 is positioned at a distance from the peripheral wall portion 11. As a result, a gap 84 is provided between the cylindrical portion 81 and the peripheral wall portion 11. In addition, a gap 84 is also provided between the peripheral wall portion 11 and a portion of the skirt portion 82 that is not in contact with the peripheral wall portion 11.

[0070] On the peripheral wall portion 11 of the portion defining the filter chamber S2, a plurality of gas ejection ports 12 are provided along the circumferential direction and the axial direction. More specifically, a plurality of gas ejection ports 12 are provided in a portion of the peripheral wall portion 11 that faces the filter 80 and does not contact the filter 80. These plurality of gas ejection ports 12 are for guiding the gas after passing through the flow-through portion 83 of the filter 80 to the outside of the housing.

[0071] <B. Method for Manufacturing Filter> FIG. 6 is an enlarged perspective view of the surface portion of the filter shown in FIG. 1. FIGS. 7 and 8 are schematic diagrams for explaining the manufacturing method of the filter shown in FIG. 1. Next, an example of the manufacturing method of the filter 80 included in the cylinder type gas generator 1A according to the present embodiment will be described with reference to FIGS. 6 to 8.

[0072] In manufacturing the filter 80, first, a long perforated metal plate is prepared. In the present embodiment, as shown in FIG. 6, expanded metal is used as the perforated metal plate. Expanded metal is formed by making slits in a metal plate in a staggered pattern and expanding this to form a large number of openings AP and processing it into a mesh shape. The large number of openings AP are provided substantially evenly over the entire surface of the perforated metal plate.

[0073] Next, the perforated metal plate is wound. More specifically, the perforated metal plate is wound in a spiral shape such that one end in the longitudinal direction of the long perforated metal plate is positioned inside and the other end is positioned outside. Thereby, a laminate 100 (see FIG. 7) including a plurality of layers positioned along the radial direction and having a hollow cylindrical shape as a whole is formed.

[0074] Note that, if necessary, each layer may be welded at the joining margin portion where the portion near the one end of the perforated metal plate and the portion near the other end overlap.

[0075] Next, as shown in Fig. 7, a substantially cylindrical outer mold 101 is fitted onto the laminate 100 in the axial direction except for both end portions. The outer mold 101 is used to prevent deformation of the laminate 100 in the bending process described below. The shape of the outer mold 101 is not particularly limited to a substantially cylindrical shape and can be changed as appropriate. Furthermore, the outer mold 101 does not necessarily have to be made of a single member, and may be made of, for example, a half-split body.

[0076] Next, bending is performed on one axial end of the laminate 100. More specifically, as shown in Fig. 7, the tip of an inner die 102 for bending is inserted into the laminate 100 from one axial end side of the laminate 100, with the outer peripheral surface fixed by an outer die 101. The inner die 102 is configured to be movable in any direction by an actuator such as a servo motor attached thereto.

[0077] The inner mold 102 has a portion at its tip that has a shape corresponding to the skirt portion 82. In this embodiment, the inner mold 102 has a portion at its tip that is shaped like a truncated cone. The angle of the inclined portion of this truncated cone is the same as the angle of inclination of the skirt portion 82.

[0078] When the inner mold 102 configured in this manner is inserted into the laminate 100, one axial end of the laminate 100 is deformed to conform to the tip shape of the inner mold 102, as shown in Fig. 8. As a result, a skirt portion 82 is formed at one axial end of the laminate 100.

[0079] Next, the other axial end of the laminate 100 is similarly bent, resulting in the production of a filter 80 having a tubular portion 81 and skirt portions 82 extending continuously from each of a pair of axial ends of the tubular portion 81, as shown in Fig. 1 .

[0080] As described above, by manufacturing the filter 80, it becomes possible to easily manufacture the filter 80 having the skirt portion 82 with a manufacturing apparatus having a simple configuration.

[0081] Further, in the filter 80 manufactured in this way, the above-described flow passage portion 83 is formed by the communication of a large number of openings AP provided in each layer with each other. The flow passage portion 83 is a meandering flow path for the working gas to flow. Therefore, the flow passage portion 83 exhibits the function of allowing the working gas to pass while cooling it, and at the same time exhibits the functions of diffusing the gas and collecting slag.

[0082] <C. Method of Assembling the Filter into the Housing> FIGS. 9 and 10 are schematic cross-sectional views for explaining a method of assembling the filter into the housing. Next, referring to FIGS. 9 and 10, an example of a method of assembling the filter 80 into the housing in the cylinder-type gas generator 1A according to the present embodiment will be described.

[0083] When assembling the filter 80 into the housing, first, as shown in FIG. 9, the filter 80 and the peripheral wall portion 11 to which the closing member 30 is previously fixed are prepared. The outer diameter of the skirt portion 82 of the filter 80 prepared here is configured to be the same as or slightly smaller than the inner diameter of the peripheral wall portion 11.

[0084] Next, the filter 80 is inserted into the peripheral wall portion 11. More specifically, first, the filter 80 is positioned substantially coaxially with the peripheral wall portion 11. Next, the filter 80 positioned in this way is inserted into the peripheral wall portion 11 from the side of the second skirt portion 82b. As a result, as shown in FIG. 10, the axial end face of the second skirt portion 82b of the filter 80 abuts against the closing member 30.

[0085] Next, the partition member 50 is inserted into the peripheral wall portion 11. More specifically, first, the partition member 50 is positioned substantially coaxially with the peripheral wall portion 11. Next, the partition member 50 thus positioned is press-fitted into the inside of the peripheral wall portion 11 from the side of the partition wall portion 52. As a result, the partition wall portion 52 abuts against the axial end face of the first skirt portion 82a of the filter 80 (see FIGS. 1 and 3).

[0086] By press-fitting the partition member 50 in this way, an axial load is applied to the filter 80 from the partition member 50 in a state where the filter 80 is sandwiched between the closing member 30 and the partition member 50 in the axial direction. As a result, the pair of skirt portions 82 of the filter 80 are deformed so as to increase in diameter, and as a result, all circumferential portions of the axial end portions of each of the pair of skirt portions 82 come into contact with the peripheral wall portion 11.

[0087] Note that the procedure for assembling the filter 80 to the housing described above is merely an example, and the filter 80 may be assembled to the housing by an assembly procedure different from this one.

[0088] For example, as another example, the filter 80 may be inserted into the peripheral wall portion 11 in a state before the closing member 30 is fixed. In this case, the filter 80 may be inserted into the peripheral wall portion 11 from the side of the first skirt portion 82a or may be inserted into the peripheral wall portion 11 from the side of the second skirt portion 82b. In other words, the filter 80 may be inserted into either of the pair of open ends of the peripheral wall portion 11.

[0089] <D. Operation of the Cylinder-Type Gas Generator> Next, referring to FIG. 1, the operation during the operation of the cylinder-type gas generator 1A according to the present embodiment will be described.

[0090] When a vehicle equipped with the cylinder-type gas generator IA according to the present embodiment collides, the collision is detected by collision detection means provided separately in the vehicle, and based on this, the igniter 40 is operated by energization from a control unit provided separately in the vehicle.

[0091] When the igniter 40 operates, the ignition charge or, in addition thereto, the primer charge burns, increasing the pressure within the ignition part 41. As a result, the squib cup of the ignition part 41 cracks, and the hot particles generated by the burning of the ignition charge or, in addition thereto, the primer charge flow out of the ignition part 41. The hot particles that reach the gas generating agent 60 burn the gas generating agent 60. Thereby, a large amount of gas is generated in the gas generating agent housing chamber S1.

[0092] Along with this, the pressure in the gas generating agent housing chamber S1 increases, and when the internal pressure of the gas generating agent housing chamber S1 reaches a predetermined pressure, cracks occur in the portion of the partition member 50 where the score 52a is provided and the portions in the vicinity thereof. As a result, an opening is formed in the partition wall portion 52, and the gas generating agent housing chamber S1 and the filter chamber S2 communicate with each other through the opening.

[0093] Along with this, the gas generated in the gas generating agent housing chamber S1 flows into the filter chamber S2 through the opening formed in the partition wall portion 52. The gas that has flowed into the filter chamber S2 flows along the axial direction through the hollow portion of the filter 80 and then changes its direction radially and flows through the flow-through portion 83 of the filter 80. At that time, heat is taken away by the filter 80 and the gas is cooled, and the slag contained in the gas is removed by the filter 80.

[0094] Then, the gas after flowing through the flow-through portion 83 is ejected to the outside of the housing through the gas ejection port 12 provided in the peripheral wall portion 11. The ejected gas is introduced into the interior of an airbag provided adjacent to the cylinder-type gas generator 1A, and the airbag is inflated and deployed. Note that the auto-ignition agent 61 burns together when the gas generating agent 60 burns.

[0095] <E. Parentheses> In cylinder-shaped gas generator 1A according to the present embodiment, as described above, filter 80 has skirt portion 82, and as a result, cylindrical portion 81 of filter 80 is positioned away from peripheral wall portion 11, and gap portion 84 is provided between cylindrical portion 81 and peripheral wall portion 11. Furthermore, gas outlet 12 is provided at least in a portion of peripheral wall portion 11 that faces filter 80 but does not abut against filter 80.

[0096] By configuring in this manner, the gas generated by the combustion of the gas generating agent 60 passes through almost the entire area of ​​the filter 80, resulting in an improved utilization efficiency of the filter 80. If the gap 84 is not provided (i.e., if most of the outer peripheral surface of the filter 80 abuts against the inner peripheral surface of the peripheral wall portion 11), the flow resistance in the flow passage portion 83 located directly below the gas outlet 12 will be lower than the flow resistance in the remaining portion of the flow passage portion 83, and as a result, most of the gas will flow through the portion of the flow passage portion 83 located directly below the gas outlet 12. However, by providing the gap 84 as described above, the flow resistance in the flow passage portion 83 can be made uniform over the entire area.

[0097] Furthermore, in cylinder-shaped gas generator 1A according to the present embodiment, as described above, flow portion 83 is provided not only in tubular portion 81 but also in skirt portion 82. By being configured in this manner, the utilization efficiency of filter 80 can be further improved.

[0098] In this way, filter 80 has skirt portion 82 provided with flow passage portion 83, thereby making it possible to provide cylinder-shaped gas generator 1A in which the utilization efficiency of filter 80 is dramatically improved.

[0099] Furthermore, in cylinder-shaped gas generator 1A according to the present embodiment, as described above, skirt portion 82 of filter 80 is inclined so as to approach peripheral wall portion 11 the further it becomes from cylindrical portion 81. By configuring in this manner, filter 80 having skirt portion 82 can be easily manufactured by a simplified manufacturing method such as the filter manufacturing method described above.

[0100] Therefore, by using the cylinder-shaped gas generator according to the present embodiment, it is possible to provide a gas generator in which the filter utilization efficiency is improved and the manufacturing process is simplified.

[0101] Furthermore, in cylinder-shaped gas generator 1A according to the present embodiment, as described above, first skirt portion 82a and second skirt portion 82b are located at the center of filter 80 in the axial direction of the housing and have shapes that are plane-symmetrical with respect to a plane that is orthogonal to the axial direction. This makes it unnecessary to distinguish between the front and back of filter 80 during assembly, and as a result, manufacture of cylinder-shaped gas generator 1A can be facilitated.

[0102] Furthermore, by configuring cylinder-shaped gas generator 1A according to the present embodiment, it is possible to stabilize the gas output characteristics. This point will be described in detail below, in comparison with cylinder-shaped gas generator 1X according to a comparative example. Fig. 11 is a schematic diagram of the cylinder-shaped gas generator according to the comparative example in a first state. Fig. 12 is a schematic diagram of the cylinder-shaped gas generator according to the comparative example in a second state. Fig. 13 is a schematic cross-sectional view taken along line XIII-XIII in Fig. 12.

[0103] As shown in Figures 11 and 12, cylinder-shaped gas generator 1X in accordance with the comparative example differs from cylinder-shaped gas generator 1A in accordance with the present embodiment only in that filter 80X does not have a skirt portion.

[0104] As filter 80X does not have a skirt portion in this way, cylinder-shaped gas generator 1X can be in either a first state shown in Figure 11 or a second state shown in Figure 12, depending on the arrangement of assembled filter 80X. Furthermore, if filter 80X is not sufficiently fixed in the axial direction, cylinder-shaped gas generator 1X can change from the first state to the second state, or from the second state to the first state.

[0105] As shown in FIG. 11, when cylinder-shaped gas generator 1X is in a first state in which filter 80X is arranged substantially coaxially with peripheral wall portion 11, gap portion 84 is provided over the entire circumferential direction.

[0106] On the other hand, as shown in Figures 12 and 13, when cylinder-shaped gas generator 1X is in a second state in which filter 80X is positioned eccentrically with respect to the central axis of peripheral wall portion 11, gap portion 84 is provided between peripheral wall portion 11 and tubular portion 81 at a portion located away from peripheral wall portion 11, while gap portion 84 is not provided between peripheral wall portion 11 and tubular portion 81 at a portion abutting peripheral wall portion 11.

[0107] In cylinder-shaped gas generator 1X configured in this manner, there is a concern that the gas output characteristics may become unstable depending on the arrangement of filter 80X.

[0108] For example, after mounting a cylinder-shaped gas generator 1X having specific specifications on a tank, cylinder-shaped gas generator 1X is activated to release gas into the tank, and the maximum value P1 of the pressure inside the tank and the maximum value P2 of the internal pressure of gas generating agent storage chamber S1 are measured. In this case, it has been confirmed that P1 for cylinder-shaped gas generator 1X in the second state is approximately 5% higher than P1 for cylinder-shaped gas generator 1X in the first state, and P2 for cylinder-shaped gas generator 1X in the second state is approximately 10% higher than P2 for cylinder-shaped gas generator 1X in the first state. This is because the flow of gas passing through filter 80X becomes uneven in the circumferential direction in the second state.

[0109] In this regard, in cylinder-shaped gas generator 1A according to the present embodiment, filter 80 has skirt portion 82, and therefore gap 84 can be reliably provided over the entire circumference between tubular portion 81 and peripheral wall portion 11, regardless of the arrangement of filter 80. Therefore, it is possible to obtain a cylinder-shaped gas generator with stabilized gas output characteristics.

[0110] Furthermore, in cylinder-shaped gas generator 1A according to the present embodiment, as described above, the axial end face of first skirt portion 82a provided on filter 80 abuts against partition wall portion 52 of partition member 50. By configuring in this manner, cylinder-shaped gas generator 1A with enhanced safety can be obtained. This point will be described in detail below, comparing cylinder-shaped gas generator 1A according to the present embodiment with cylinder-shaped gas generator 1X according to a comparative example.

[0111] As described above, when the cylinder-shaped gas generator is activated, the internal pressure of the gas generating agent storage chamber S1 reaches a predetermined pressure, causing rupture at the portion of the partition member 50 where the score 52a is provided and at a portion in the vicinity thereof. More specifically, rupture occurs at a portion of the partition wall portion 52 of the partition member 50 that is more inward than the portion with which the filter abuts (hereinafter, this portion will also be referred to as the "rupture portion").

[0112] As shown in FIGS. 1 and 11, rupture portion C1 in cylinder-shaped gas generator 1A is configured to be larger than rupture portion C2 in cylinder-shaped gas generator 1X by the amount that filter 80 has first skirt portion 82a.

[0113] This makes it possible to make the rate at which the internal pressure of gas generating agent storage chamber S1 is reduced by cleaving cleavage portion C1 greater than the rate at which the internal pressure of gas generating agent storage chamber S1 is reduced by cleaving cleavage portion C2. Therefore, by using cylinder-shaped gas generator 1A according to the present embodiment, it is possible to provide a gas generator that is safer than cylinder-shaped gas generator 1X according to the comparative example, in which the increase in internal pressure of gas generating agent storage chamber S1 after cleavage of the cleavage portion is suppressed.

[0114] Furthermore, in cylinder-shaped gas generator 1A according to the present embodiment, as described above, the axial end of skirt portion 82 abuts against peripheral wall portion 11 at its entire circumferential portion. By being configured in this manner, the occurrence of rattle in the radial direction of filter 80 can be effectively suppressed, and as a result, the generation of abnormal noise caused by this rattle can be suppressed.

[0115] In the above-described embodiment, filter 80 is made of expanded metal (see FIG. 6), but filter 80 may be made of hook metal as shown in FIG. 14. Hook metal is made by drilling holes in a metal plate and flattening the metal by crushing burrs that form around the edges of the holes. Filter 80 may also be made of, for example, a plain woven wire mesh or a stockinette knit wire mesh as shown in FIG. 15, an aggregate of crimped metal wires, or a combination of these compressed by a press.

[0116] Furthermore, in the present embodiment described above, an example has been given in which skirt portion 82 of filter 80 is inclined so as to approach peripheral wall portion 11 as it moves away from cylindrical portion 81, but skirt portion 82 may also be curved so as to approach peripheral wall portion 11 as it moves away from cylindrical portion 81. Even in this case, filter 80 can be manufactured by a method similar to the filter manufacturing method described above. Therefore, a gas generator can be manufactured with ease.

[0117] Furthermore, in the above-described embodiment, an example has been given in which the first skirt portion 82a and the second skirt portion 82b are located at the center of the filter 80 in the axial direction of the housing and have a plane-symmetrical shape with respect to a plane perpendicular to the axial direction, but the first skirt portion 82a and the second skirt portion 82b do not necessarily have to have such a plane-symmetrical shape.

[0118] (First Modification) Fig. 16 is a schematic view of a cylinder-shaped gas generator pertaining to a first modified example in a third state. Fig. 17 is a schematic view of a cylinder-shaped gas generator pertaining to a first modified example in a fourth state. Fig. 18 is a schematic cross-sectional view taken along line XVIII-XVIII in Fig. 17. Hereinafter, with reference to Figs. 16 to 18, a cylinder-shaped gas generator 1A1 pertaining to a first modified example based on the embodiment described above will be described.

[0119] As shown in Figures 16 and 17, cylinder-shaped gas generator 1A1 according to the first modified example differs from cylinder-shaped gas generator 1A according to the embodiment described above in that the outer diameter of skirt portion 82 of filter 80 after assembly is configured to be smaller than the inner diameter of peripheral wall portion 11.

[0120] Cylinder-shaped gas generator 1A1 configured in this manner can be in either the third state shown in Figure 16 or the fourth state shown in Figure 17, depending on the arrangement of assembled filter 80. Furthermore, if filter 80 is not sufficiently fixed in the axial direction, cylinder-shaped gas generator 1A1 can change from the third state to the fourth state, or from the fourth state to the third state, at any time.

[0121] As shown in FIG. 16, when cylinder-shaped gas generator 1A1 is in a third state in which filter 80 is arranged substantially coaxially with peripheral wall portion 11, gap portion 84 is provided over the entire circumferential direction.

[0122] 17 and 18 , when cylinder-shaped gas generator 1A1 is in a fourth state in which filter 80 is arranged eccentrically with respect to the central axis of peripheral wall portion 11, a circumferential portion of the axial end of skirt portion 82 abuts against peripheral wall portion 11. Even in this case, filter 80 has skirt portion 82, so that cylindrical portion 81 is positioned at a distance from peripheral wall portion 11, and thereby gap portion 84 is provided between cylindrical portion 81 and peripheral wall portion 11 over the entire circumferential direction.

[0123] Even when configured in this manner, effects similar to those described in the above-mentioned embodiment can be obtained, and a gas generator can be obtained that improves the filter utilization efficiency and simplifies manufacturing.

[0124] Furthermore, as described above, the outer diameter of the skirt portion 82 of the filter 80 is configured to be smaller than the inner diameter of the peripheral wall portion 11, which makes it possible to easily insert the filter 80 into the peripheral wall portion 11 (see Figure 9) when assembling the filter 80 to the housing.

[0125] (Second Modification) Fig. 19 is a schematic diagram of a cylinder-shaped gas generator according to Modification 2. Hereinafter, with reference to Fig. 19, a cylinder-shaped gas generator 1A2 according to Modification 2 based on the embodiment described above will be described.

[0126] As shown in FIG. 19, cylinder-shaped gas generator 1A2 according to the second modified example differs from cylinder-shaped gas generator 1A according to the embodiment described above in that skirt portion 82 of filter 80 includes only first skirt portion 82a and does not include second skirt portion 82b.

[0127] In this way, even when the skirt portion 82 extends continuously from only one of a pair of axial ends of the tubular portion 81, a gap portion 84 can be reliably provided around the entire circumference between the tubular portion 81 and the peripheral wall portion 11 regardless of the arrangement of the filter 80.

[0128] Even when configured in this manner, effects similar to those described in the above-mentioned embodiment can be obtained, and a gas generator can be obtained that improves the filter utilization efficiency and simplifies manufacturing.

[0129] Furthermore, in this configuration, it is sufficient to perform the above-described bending process (see FIGS. 7 and 8) performed in manufacturing the filter 80 only on one axial end of the laminate 100. In other words, there is no need to perform bending on both axial ends of the laminate 100.

[0130] Furthermore, with this configuration, when assembling the filter 80 to the housing, it is possible to easily insert the filter 80 into the peripheral wall portion 11 (see FIG. 9 ). This is because the filter 80 is inserted into the peripheral wall portion 11 from the side of the cylindrical portion 81, which has an outer diameter smaller than the outer diameter of the skirt portion 82.

[0131] In this way, by configuring cylinder-shaped gas generator 1A2 according to this modified example, a gas generator can be obtained that is further facilitated in manufacture.

[0132] (Third Modification) Fig. 20 is a schematic diagram of a cylinder-shaped gas generator according to Modification 3. Hereinafter, with reference to Fig. 20, a cylinder-shaped gas generator 1A3 according to Modification 3 based on the embodiment described above will be described.

[0133] As shown in FIG. 20, cylinder-shaped gas generator 1A3 according to the third modified example differs from cylinder-shaped gas generator 1A according to the embodiment described above in that skirt portion 82 of filter 80 includes only second skirt portion 82b, and does not include first skirt portion 82a.

[0134] In this way, even when the skirt portion 82 extends continuously from only one of a pair of axial ends of the tubular portion 81, a gap portion 84 can be reliably provided around the entire circumference between the tubular portion 81 and the peripheral wall portion 11 regardless of the arrangement of the filter 80.

[0135] Even when configured in this manner, effects similar to those described in the above-mentioned embodiment can be obtained, and a gas generator can be obtained that improves the filter utilization efficiency and simplifies manufacturing.

[0136] Furthermore, even in such a configuration, a gas generator can be obtained that is further facilitated in manufacture, similar to cylinder-shaped gas generator 1A2 according to the second modified example described above.

[0137] (Other forms, etc.) The characteristic configurations shown in the above-described embodiments of the present invention and their modifications can naturally be combined with one another within the scope of the gist of the present invention.

[0138] Furthermore, in the above-described embodiment of the present invention and its modified examples, the present invention has been described by way of example only as being applied to a cylinder-type gas generator incorporated in a side airbag device, but the application of the present invention is not limited to this, and the present invention can also be applied to cylinder-type gas generators incorporated in curtain airbag devices, knee airbag devices, seat cushion airbag devices, etc., and so-called T-shaped gas generators which have an elongated outer shape similar to a cylinder-type gas generator.

[0139] As such, the above-described embodiments and their modifications disclosed herein are illustrative in all respects and are not limiting. The technical scope of the present invention is defined by the claims, and includes all modifications within the meaning and scope of the claims. [Explanation of symbols]

[0140] 1A, 1A1, 1A2, 1A3, 1X Cylinder-type gas generator, 10 Housing body, 11 Peripheral wall portion, 12 Gas outlet, 20 Holder, 21 Penetration portion, 22 Crimping portion, 23 Recess, 30 Closure member, 40 Igniter, 41 Ignition portion, 42 Terminal pin, 43 Sealing member, 50 Partition member, 51 Annular wall portion, 52 Partition wall portion, 52a Score, 60 Gas generating agent, 61 Auto-ignition agent, 70 Coil spring, 71 Spring portion, 72 Pressing portion, 80, 80X Filter, 81 Cylindrical portion, 82 Skirt portion, 82a First skirt portion, 82b Second skirt portion, 83 Flow portion, 84 Gap portion, 91-93 Welded portion, 100 Laminate, 101 Outer mold, 102 Inner mold, AP opening, C1, C2 cleavage section, S1 gas generating agent storage chamber, S2 filter chamber.

Claims

1. a housing having a cylindrical peripheral wall portion provided with a gas outlet, one end and the other end in an axial direction being closed, and including therein a gas generating agent storage chamber in which a gas generating agent is stored and a filter chamber in which a filter is disposed; a partition member that partitions the internal space of the housing in the axial direction so that the gas generating agent storage chamber is located on the one end side and the filter chamber is located on the other end side; an igniter assembled to the one end of the housing, the filter has a cylindrical portion extending in a direction substantially parallel to the axial direction, and a skirt portion extending continuously from at least one of a pair of ends of the cylindrical portion located in the axial direction, and inclined or curved so as to approach the peripheral wall portion as it moves away from the cylindrical portion; The cylindrical portion and the skirt portion are provided with a flow passage portion through which gas can pass, The filter has the skirt portion, and the cylindrical portion is positioned away from the peripheral wall portion, thereby providing a gap between the cylindrical portion and the peripheral wall portion, A gas generator, wherein the gas outlet is provided at least in a portion of the peripheral wall that faces the filter but does not abut against the filter.

2. the skirt portion includes a first skirt portion provided at an end portion of the pair of ends located in the axial direction of the cylindrical portion on the one end side, 2. The gas generator according to claim 1, wherein an axial end face of said first skirt portion abuts against said partition member.

3. the housing has a closing portion that closes the other end, the skirt portion includes a second skirt portion provided at an end portion of the pair of ends located in the axial direction of the cylindrical portion on the side of the other end portion, 3. The gas generator according to claim 2, wherein an axial end face of said second skirt portion abuts against said obstruction portion.

4. The gas generator according to claim 1 , wherein at least a portion of the skirt portion in the circumferential direction is in contact with the peripheral wall portion.

5. 5. The gas generator according to claim 4, wherein the entire circumferential portion of the skirt portion abuts against the peripheral wall portion.

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