Gas generator

Abstract

A gas generator can be obtained which can easily electrically conduct the metal portion of the bottom of the short-circuit plug and the metal holder without increasing the cost. The gas generator has a long and substantially cylindrical outer shape, includes a case (10), a connector connecting portion (20) mounted near one open end of the case (10), a holder (25), a directional member (53), an igniter (50) held by the holder (25) and igniting a gas generating agent (31), a closing member mounted to the other end of the case (10) in a manner of closing the other open end of the case (10), and a filter. The metal portion of the bottom of the short-circuit plug (40) fitted to the connector connecting portion (20) and the holder (25) are electrically conducted via the electrically conductive resin (40).

Description

Technical Field

[0001] The present invention relates to a gas generator for use in an airbag device as an occupant protection device mounted in automobiles and the like. Background Technology

[0002] In conventional gas generators, various designs have been implemented to remove static electricity, including retaining members molded from conductive resin (see, for example, Patent Document 1 below). Furthermore, for example, during the stage before the gas generator is assembled into the airbag module (during delivery, etc.), a short-circuit plug for short-circuiting the igniter is sometimes installed at the point where the external connector is connected during assembly into the airbag module. Among these short-circuit plugs, there are those that also have the function of removing static electricity accumulated in the gas generator via a metal retaining member.

[0003] Existing technical documents

[0004] Patent documents

[0005] Patent Document 1: Japanese Patent Application Publication No. 2017-61185 Summary of the Invention

[0006] The problem the invention aims to solve

[0007] When using this short-circuit plug, the retainer can also be made of metal to remove static electricity from the side of the plug. However, metal is more difficult to process, thus increasing costs. Additionally, a metal retainer tends to be heavier. Therefore, by making the retainer of resin, weight reduction can be achieved. However, in this case, grounding metal portions must be provided on the sides and bottom of the retainer. However, gaps can easily form between the bottom metal portion and the metal retainer, making contact difficult.

[0008] Therefore, the object of the present invention is to provide a gas generator that can easily fill the gap formed between the bottom metal part and the metal retainer without increasing costs, so that the bottom metal part of the short-circuit plug and the metal retainer are electrically connected.

[0009] Solution for solving the problem

[0010] (1) The gas generator of the present invention is characterized in that,

[0011] This gas generator has the following features:

[0012] A housing containing a gas generating agent that produces gas through combustion, and including a filter for the gas to pass through inside, the housing having a gas outlet for ejecting the gas at a position corresponding to the filter;

[0013] An igniter that enables the gas generator to ignite and burn;

[0014] A resin-made cylindrical portion disposed at one axial end of the housing, which, when assembled to an external device, can be fitted with an external connector for energizing the igniter at said end, and can also be fitted with short-circuit plugs having metal portions on at least a portion of the side and bottom surfaces; and

[0015] A cylindrical retainer, made of metal or alloy, is fixed to the housing in a manner opposite to the cylindrical portion; this retainer holds a portion of the igniter.

[0016] When the short-circuit plug is fitted into the cylindrical portion, at least a portion of the portion of the retainer opposite the short-circuit plug and the metal portion of the short-circuit plug are electrically connected via a conductive resin or conductive grease.

[0017] (2) In the gas generator of (1) above, it is preferable that the conductive resin or the conductive grease is at least attached to the portion of the retainer opposite to the metal portion.

[0018] (3) In the gas generator of (2) above, it is preferable that an annular surface is formed on the cylindrical part side of the retainer, and the conductive resin or the conductive grease is attached around the annular surface.

[0019] (4) In the gas generator of (1) above, it is preferable that the metal part is in contact with at least a portion of the bottom surface of the short-circuit plug, the bottom surface being the portion opposite to the retainer.

[0020] The effects of the invention

[0021] According to the present invention, a gas generator can be provided that can easily fill the gap formed between the bottom metal portion and the metal retainer without increasing costs, so that the bottom metal portion of the short-circuit plug and the metal retainer are electrically connected. Attached Figure Description

[0022] Figure 1 This is a schematic diagram (partially omitted) showing the internal structure of a gas generator according to an embodiment of the present invention, partially shown in cross-section.

[0023] Figure 2 It means Figure 1 A diagram showing the area near one end of a gas generator.

[0024] Figure 3 It is Figure 2 The magnified view of region A.

[0025] Figure 4 It indicates assembly at Figure 1 A three-dimensional view of the state of the retaining element before the gas generator. Detailed Implementation

[0026] The following is for reference Figures 1-4 The internal structure of the cylindrical gas generator according to the embodiments of the present invention will be described.

[0027] (Structure of gas generator 100)

[0028] The gas generator 100 has an elongated, generally cylindrical shape and includes a housing 10, a connector connection portion 20 (cylindrical portion) mounted near one open end of the housing 10, a retainer 25, a directional member 53, and a closing member 12 mounted at the other end of the housing 10 in a manner that closes the other open end of the housing 10.

[0029] The housing 10 has peripheral walls 10a, 10c, 10d, and 10e, and is constructed from a long, cylindrical member with openings at both ends in the axial direction. Additionally, a gas outlet 11 is provided on the peripheral wall near the end of the housing 10 on the side where the sealing member 12 is mounted. This gas outlet 11 is a hole for ejecting gas generated inside the gas generator 100 to the outside, and multiple outlets are provided along the circumference and axial direction of the housing 10.

[0030] The closing component 12 is a component made of metal such as stainless steel, steel, aluminum alloy, or stainless steel alloy. Furthermore, as... Figure 1 As shown, with the sealing member 12 in contact with the other end of the filter 41 and inserted into the housing 10 near the other end of the housing 10, the portion of the peripheral wall 10a of the housing 10 corresponding to a portion of the sealing member 12 is radially reduced inward (riveted) to fix the sealing member 12 relative to the housing 10.

[0031] The connector connection portion 20 is a generally cylindrical member made of resin. On the side opposite to the holding position of the igniter 50, it has: a fitting portion 21, which can be fitted with an external connector (not shown) for energizing the igniter 50 and can also fit a short-circuit plug 30; an annular groove portion 22, which is formed on the outer peripheral surface in a circumferentially extending manner; and a flange portion 26, which is formed at the end of the annular groove portion 22 on the side of the holding member 25. The flange portion 26 is formed with an outer diameter smaller than the outer diameter of the annular portion 27 of the holding member 25. The annular portion 27 has a portion (contact portion) on its outer periphery that contacts the inner wall of the housing. Furthermore, the connector connection portion 20 is riveted and fixed relative to the housing 10 by reducing the diameter (riveting) of the portion of the peripheral wall 10e of the housing 10 corresponding to the flange portion 26 provided on the outer peripheral surface of the connector connection portion 20 radially inward and engaging with the flange portion 26. Furthermore, the end of the retainer 25 on the connector connection 20 side is inserted inside the connector connection 20. Therefore, when the peripheral wall 10e of the housing 10 is radially reduced inward, the flange 26 is clamped by the end of the retainer 25 on the connector connection 20 side and the inner wall of the peripheral wall 10e of the housing 10, thereby more firmly fixing the connector connection 20 to the housing 10. That is, the sealing between the housing 10 and the retainer can be ensured. As a variation, the structure could also be as follows: instead of the flange 26, a simple end (without a radially protruding flange) continuous from the surface of the annular groove 22 is clamped by the end of the retainer 25 on the connector connection 20 side and the inner wall of the peripheral wall 10e of the housing 10.

[0032] Here, as the raw material for the connector connection part 20, a resin material with excellent heat resistance, durability, and corrosion resistance after curing can be appropriately selected and used. In this case, it is not limited to thermosetting resins such as epoxy resin, but thermoplastic resins such as polybutylene terephthalate resin, polyethylene terephthalate resin, polyamide resin (e.g., nylon 6, nylon 66, etc.), polypropylene sulfide resin, polypropylene oxide resin, and polyacetal resin can also be used. When these thermoplastic resins are selected as raw materials, in order to ensure the mechanical strength of the connector connection part 20 after molding, it is preferable to contain glass fiber or the like as a filler in these resin materials. However, if sufficient mechanical strength can be ensured by thermoplastic resin alone, it is not necessary to add the filler as described above. The directional member 53 can also be formed from the same raw material as the connector connection part 20.

[0033] Furthermore, as described above, a female connector is formed in the mating portion 21 of the connector connection portion 20. This female connector is the part for connecting an external connector of the wiring harness that transmits signals from a collision detection mechanism separately positioned relative to the gas generator 100. Furthermore, before assembling with external devices such as the airbag module, a short-circuit plug 30 is installed on the female connector. This short-circuit plug 30 has at least a portion (not shown) of a metal portion on its side and the bottom surface (the surface opposite the retainer 25) on the ignition side for removing static electricity. This short-circuit plug 30 is installed to prevent malfunction of the cylindrical gas generator 100 due to electrostatic discharge during transport of the gas generator 100, etc. During the assembly stage of the airbag device, the short-circuit plug 30 is released from contact with the terminal pin 52 by inserting the male connector of the wiring harness into the female connector.

[0034] The retainer 25 has an annular surface 28 formed on the connector connection portion 20 side, and the portion contacting the inner wall of the housing 10 is larger than the outer diameter of the flange portion 26 of the connector connection portion 20. It is a generally cylindrical member made of stainless steel, steel, aluminum alloy, or stainless steel alloy. Furthermore, a portion (mainly the main body) of the igniter 50 is inserted into the retainer 25, and it has a conical fitting portion 23 for the igniter 50 to engage. A portion of the outer side of the retainer 25 is inserted into the interior of the connector connection portion 20. Additionally, as... Figure 3 As shown, at least a portion of the portion of the retainer 25 opposite to the short-circuit plug 30 and the metal portion provided at the bottom of the short-circuit plug 30 are electrically connected via conductive resin 40.

[0035] The conductive resin 40 is preferably a conductive paste containing conductive materials such as gold, silver, copper, nickel, palladium, or carbon black. Additionally, such as Figure 4As shown, by pre-coating (adhering) the conductive resin 40 around the surface 28 of the retainer 25, the retainer 25 can be electrically connected to the metal part located at the bottom of the short-circuit plug 30 even when assembled without considering the positional relationship between the retainer 25 and the metal part located at the bottom of the short-circuit plug 30 (for example, four locations are provided at equal intervals opposite to the surface 28 of the retainer 25). Furthermore, the conductive resin 40 is preferably a thermosetting or conductive adhesive that cures at room temperature for a predetermined time. The conductive resin 40 is bonded to the retainer 25 by curing, forming a layer (protrusion) of conductive resin 40 that is not easily detached from the retainer 25. This allows for reliable contact between the metal part of the short-circuit plug 30 and the layer (protrusion) of conductive resin 40. Additionally, when coating (adhering) the conductive resin 40, it is preferable to use a conductive resin with low or no flowability (high viscosity). By using a conductive resin with low flowability, even if the short-circuit plug 30 has a complex shape, the retainer 25 can be electrically connected to the metal part via the conductive resin 40. The curing of the conductive resin 40 can also be performed after assembling the retainer 25 and the short-circuit plug 30 into the housing 10. Alternatively, a conductive grease with conductivity and low or no flowability (high viscosity) can be used instead of the conductive resin 40.

[0036] With the O-ring 60 disposed inside the retainer 25, the igniter 50 is riveted to the retainer 25 by the riveting part 24 provided at the opening end. In addition, the retainer 25 is fixed to the housing 10 by forming the peripheral wall 10d (described later) and the peripheral wall 10e (described above) while the retainer 25 is held by the connector connection part 20 and the directional member 53.

[0037] The directional member 53 is a generally cylindrical member made of resin and with a bottom, comprising: an annular groove 54 (small diameter portion) for riveting and fixing, the annular groove 54 being formed on the outer peripheral surface in a circumferentially extending manner; and a bottom surface 55 having a hole 55a and a hole 55b with a diameter smaller than that of the hole 55a. The directional member 53 is fixed to the housing 10 by forming a peripheral wall 10d by reducing the diameter from the outer periphery of the housing 10 towards the inner side at a position corresponding to the annular groove 54 (riveting, etc.). Furthermore, a portion of the igniter 50 (mainly the ignition tube housing 51) and a riveting portion 24 are inserted into the directional member 53. Additionally, the directional member 53 is also a member that directs the direction of the flame generated in the igniter 50 during operation toward the gas generating agent 31 via the holes 55a and 55b. Here, as a variation, the annular groove 54 does not necessarily have to be groove-shaped, as long as it is formed to include at least the following part, the diameter of which is smaller than the diameter of the end (near surface 55) of the directional member 53 on the side opposite to the retainer 25 (the side of the gas generator 31) and to the extent that it can be fixed by a diameter reduction process.

[0038] like Figure 1 As shown, an igniter 50, which serves as an ignition mechanism for the gas generator 31, is disposed at one axial end of the housing 10. Furthermore, the igniter 50, the retaining member 25 that secures the igniter 50, the directional member 53, and the connector connection portion 20 all function as an ignition mechanism for generating a flame to ignite the granular gas generator 31, which will be described later.

[0039] like Figure 1 As shown, the igniter 50 is held together with the directional member 53 (described later) in the state of being inserted into the fitting portion 23 of the retainer 25. More specifically, the igniter 50 includes: a base frame through which a pair of terminal pins 52 pass and are held; and an ignition tube housing 51 (cup-shaped member) mounted on the base frame, on which a resistor (bridge wire) is mounted to connect to the top of the terminal pins 52 inserted into the ignition tube housing 51, and ignition propellant is filled into the ignition tube housing 51 to surround or contact the resistor. As the resistor, nickel-chromium alloy wire is generally used, and as the ignition propellant, ZPP (zirconium-potassium perchlorate), ZWPP (zirconium-tungsten-potassium perchlorate), lead astringent, etc., are generally used. In addition, the ignition tube shell 51 can be filled not only with ignition powder but also with ignition transfer powder. As the ignition transfer powder that can be prepared simultaneously with the ignition powder, a composition composed of metals / oxidants such as boron / potassium nitrate, a composition composed of titanium hydride / potassium perchlorate, or a composition composed of boron / 5-aminotetrazole / potassium nitrate / molybdenum trioxide can be used.

[0040] Upon detection of a collision, a predetermined amount of current flows through terminal pin 52 to the resistive element. The flow of this predetermined current generates Joule heat within the resistive element, causing the ignition charge to ignite. The high-temperature flame produced by the combustion ruptures the ignition tube housing 51 containing the ignition charge. When a nichrome wire is used for the resistive element, the time from the current flowing through the resistive element to the activation of the igniter 50 is less than 2 milliseconds.

[0041] In addition, the ignition tube housing 51 is generally made of metal or resin. Furthermore, the portion of the peripheral wall of the ignition tube housing 51, except for the area near the top, is riveted and fixed to the retainer 25 together with the igniter 50 via the riveting part 24.

[0042] Inside the housing 10, a gas generator 31, an AI agent 32, a coil spring 35, and an anti-bypass component 36 are disposed in the space between the igniter 50 and the filter 41.

[0043] The gas generator 31 is an integrally molded article that generates gas by being ignited by a flame produced by ignition by the igniter 50. Furthermore, the gas generator 31 is generally formed as a molded body containing fuel, oxidant, and additives. As the fuel, for example, triazole derivatives, tetraazole derivatives, guanidine derivatives, azodicarbonamide derivatives, hydrazine derivatives, or combinations thereof can be used. Specifically, nitroguanidine, guanidine nitrate, cyanoguanidine, 5-aminotetrazole, etc., are suitable examples. As the oxidant, for example, alkaline metal nitrates such as basic copper nitrate, alkaline metal carbonates such as basic copper carbonate, perchlorates such as ammonium perchlorate or potassium perchlorate, and nitrates containing cations selected from alkali metals, alkaline earth metals, transition metals, and ammonia can be used. As the nitrate, for example, sodium nitrate, potassium nitrate, etc., are suitable examples. As the additives, binders, slag-forming agents, or combustion modifiers can be included. As a binder, suitable materials include cellulose derivatives such as hydroxypropyl methylcellulose, metal salts of carboxymethyl cellulose, stearates, and other organic binders, as well as synthetic hydrotalcite and acid clay, and other inorganic binders. As a slag forming agent, suitable materials include silicon nitride, silica, and acid clay. Furthermore, suitable materials as combustion modifiers include metal oxides, ferrosilicon, activated carbon, and graphite.

[0044] The bypass member 36 has an outer peripheral wall portion 36b and a bottom portion 36a with a vulnerable portion in the center, and is welded to the housing 10 via a peripheral wall 10c, which is also a welded portion. This bypass member 36 also serves as a component that divides the housing 10 into a combustion chamber for the filter 41 and the gas generator 31. During operation, the vulnerable portion of the bottom portion 36a breaks under the pressure of the generated gas. Furthermore, the bypass member 36 is configured such that the bottom portion 36a abuts against the end of the filter 41, and the outer peripheral wall portion 36b abuts against the inner wall of the housing 10. This prevents the generated gas from bypassing between the inner wall of the housing 10 and the outer periphery of the filter 41 and leaking into the gas outlet 11. In other words, the bypass member 36 allows the gas generated during operation to flow into the filter 41 side through the broken central portion.

[0045] The helical spring 35 is disposed with one end abutting against the AI ​​agent 32. In addition, the helical spring 35 is formed in a spiral shape with the diameter decreasing from one end to the middle and increasing from the middle to the other end, pushing the gas generating agent 31 toward the igniter 50 at one end.

[0046] The AI ​​agent 32 is located approximately at the center of the igniter 50 side of the bottom surface 36a of the bypass member 36, and has an automatic ignition (AI) function that automatically ignites without relying on the operation of the igniter 50. More specifically, the AI ​​agent 32 automatically ignites at a lower temperature than the gas generator 31, thus preventing abnormal operation of the gas generator 100 caused by external heating in the event of a fire in vehicles equipped with airbag devices containing the gas generator 100.

[0047] The filter 41 is composed of a cylindrical component having a generally cylindrical hollow portion 41a at its center. Furthermore, by utilizing the filter 41 composed of the aforementioned cylindrical component, the flow resistance of the working gas during operation is suppressed to a low level, enabling efficient gas flow. For the filter 41, for example, a component obtained by winding wire or mesh made of metal such as stainless steel or steel, or a component obtained by pressing them together through a stamping process, can be used. Specifically, an assembly of knitted metal mesh, plain woven metal mesh, or embossed braided metal wire can be used. When the gas generated within the housing 10 passes through the filter 41, it functions as a cooling mechanism to cool the gas by absorbing its high temperature, and also as a removal mechanism to remove slag and other contaminants contained in the gas. Here, as a variation of the filter 41, a filter with a labyrinthine flow path formed by assembling generally cylindrical or mortar-shaped components made of metal can also be used. This allows the working gas to travel in various directions, thus enabling gas cooling and slag removal.

[0048] Furthermore, in the embodiments of the present invention described above, a filter made of so-called knitted metal mesh was exemplified as a filter. However, filters made by winding perforated metal or by winding sheet metal mesh can also be used instead. Here, perforated metal refers to a metal plate in which only openings are provided on the sheet metal member (i.e., no protrusions are provided around the perimeter of the openings), and sheet metal mesh refers to a metal plate that has openings in the sheet metal member by forming slits in a staggered pattern and expanding them, thus creating a mesh-like structure. When perforated metal or sheet metal mesh is used instead of the knitted metal mesh described above, the same effects as those described in the embodiments of the present invention described above can be obtained.

[0049] Furthermore, in the aforementioned perforated metal and metal mesh, a filter composed of a laminate is formed by winding a single metal plate-shaped member, but the structure of the filter is not limited to this structure. That is, each layer may be composed of different metal plate-shaped members, and a filter composed of a laminate may be formed by combining them; alternatively, a portion of the multiple layers may be formed by winding a single metal plate-shaped member, and the remaining layers may be formed by winding another single metal plate-shaped member, and a filter composed of a laminate may be formed by combining these layers.

[0050] Next, the operation of the gas generator 100 described above will be explained. In the event of a collision involving a vehicle equipped with an airbag device containing the gas generator 100 of this embodiment, the collision is detected by a collision detection mechanism separately provided in the vehicle, and the igniter 50 operates accordingly. When the igniter 50 operates, the pressure inside the igniter 50 increases due to the combustion of the ignition propellant, thereby causing the top of the ignition tube housing 51 of the igniter 50 to rupture, and the flame flows out from the top of the ignition tube housing 51 of the igniter 50 toward the gas generating agent 31 inside the housing 10.

[0051] The incoming flame ignites the gas generator 31 inside the casing 10, producing a large amount of gas. The combustion of the gas generator 31 causes a pressure increase inside the casing 10, and the generated gas causes a rupture in the weak point of the bottom part 36a of the bypass member 36, allowing it to flow into the hollow part 41a and the internal space 12a. The generated gas is then ejected from the gas outlet 11 through the filter 41 to the outside of the gas generator 100. Because it passes through the filter 41, the generated gas is cooled to a predetermined temperature. Furthermore, the gas ejected from the gas outlet 11 is directed into the interior of the airbag, causing the airbag to inflate and deploy.

[0052] (Main features of gas generator 100)

[0053] According to this embodiment, a gas generator 100 can be made that can easily fill the gap formed between the metal part at the bottom of the short-circuit plug 30 and the metal retainer 25 without increasing costs, so that the metal part at the bottom of the short-circuit plug 30 and the metal retainer 25 are electrically connected.

[0054] Furthermore, according to this embodiment, since the conductive resin 40 is pre-coated (attached) around the surface 28 of the retainer 25, the retainer 25 can be electrically connected to the metal part even if the positional relationship between the retainer 25 and the metal part provided at the bottom of the short-circuit plug 30 is not taken into account during assembly.

[0055] Furthermore, if a thermosetting or a conductive adhesive that cures at room temperature for a predetermined time is used in the formation of the conductive resin 40 in this embodiment, a layer (protrusion) of conductive resin 40 that is not easily detached from the retainer 25 can be easily formed.

[0056] Furthermore, according to this embodiment, the connector connection portion 20 and the directional member 53 are made of resin, while the retainer 25 is made of metal or alloy. Therefore, compared to the conventional method, the molding of the retainer becomes easier, and compared to the case where the retainer is entirely made of metal or alloy, it can be made lighter. That is, according to this embodiment, a gas generator 100 that is easier to manufacture and lighter than conventional gas generators, and whose cost can be reliably controlled, can be provided.

[0057] Furthermore, according to this embodiment, by dividing it into a connector connection portion 20, a retaining member 25, and a directional member 53, a complex shape can be formed without forming it all at once, thus providing a gas generator 100 that is easier to manufacture than in the past.

[0058] Furthermore, according to this embodiment, the directional member 53 can be used as a protective member for the riveting portion 24 of the retainer 25.

[0059] The embodiments of the present invention have been described above based on the accompanying drawings, but it should be understood that the specific structure is not limited to these embodiments. The scope of the present invention is not shown by the description of the above embodiments, but by the claims, and includes all modifications within the meaning and scope equivalent to the claims. For example, the present invention can be applied to a disc-shaped gas generator in which a short-circuit plug similar to the short-circuit plug 30 described above can be fitted into the connector engagement portion of a metal retainer holding the igniter. Here, a disc-shaped gas generator refers to a housing having a bottomed cylindrical upper side shell and a bottomed cylindrical lower side shell, which are combined and joined together with their opening surfaces facing each other to form a housing, a retainer holding the igniter is formed in approximately the center of the lower side shell, and a gas generating agent is filled inside the housing.

[0060] Furthermore, in the above embodiments, the method for reducing the diameter of the housing was described using riveting as an example, but any processing method that can reduce the diameter of the housing is acceptable.

[0061] Explanation of reference numerals in the attached figures

[0062] 10. Housing; 10a, 10c, 10d, 10e. Peripheral wall; 11. Gas outlet; 12. Sealing component; 12a. Internal space; 20. Connector connection part; 21, 23. Fitting part; 22, 54. Annular groove part; 24. Riveting part; 25. Retaining member; 26. Flange part; 27. Annular part; 28. Surface; 30. Short-circuit plug; 31. Gas generator; 32. Al agent; 35. Helical spring; 36. Anti-bypass component; 36a. Bottom part; 36b. Outer peripheral wall part; 40. Conductive resin; 41. Filter; 41a. Hollow part; 50. Igniter; 51. Igniter tube shell; 52. Terminal pin; 53. Directional component; 55. Bottom surface; 55a, 55b. Hole; 60. O-ring; 100. Gas generator.

Claims

1. A gas generator, characterized in that, This gas generator has the following features: A housing containing a gas generating agent that produces gas through combustion, and including a filter for the gas to pass through inside, the housing having a gas outlet for ejecting the gas at a position corresponding to the filter; An igniter that enables the gas generator to ignite and burn; A resin-made cylindrical portion disposed at one axial end of the housing, which, when assembled to an external device, can be fitted with an external connector for energizing the igniter at said end, and can also be fitted with short-circuit plugs having metal portions on at least a portion of the side and bottom surfaces; and A cylindrical retainer, made of metal or alloy, is fixed to the housing in a manner opposite to the cylindrical portion; this retainer holds a portion of the igniter. When the short-circuit plug is fitted into the cylindrical portion, at least a portion of the portion of the retainer opposite the short-circuit plug and the metal portion of the short-circuit plug are electrically connected via a conductive resin or conductive grease.

2. The gas generator according to claim 1, characterized in that, The conductive resin or the conductive grease is at least attached to the portion of the retainer opposite the metal portion.

3. The gas generator according to claim 2, characterized in that, An annular surface is formed on the cylindrical portion side of the retainer. The conductive resin or conductive grease is attached around the entire circumference of the annular surface.

4. The gas generator according to claim 1, characterized in that, The conductive resin contacts at least a portion of the metal portion located on the bottom surface of the short-circuit plug, the bottom surface being the portion opposite to the retainer.

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