Gas generator

Abstract

To improve sealing performance with a simple configuration in a gas generator equipped with a female connector portion made of resin molded body used to energize an igniter.SOLUTION: A gas generator 1A includes a housing, an igniter 40, a male connector 130, and a female connector portion 34. The female connector portion 34 includes a recessed portion 35 into which the male connector 130 can be inserted. The male connector 130 has an annular opposing surface 132a that faces an axial end surface 34a that is positioned so as to surround the recessed portion 35 of the female connector portion 34 in an attached state where the male connector is inserted into the female connector portion 34. A seal portion 134 that is interposed between the annular opposing surface 132a and the axial end surface 34a and seals the internal space of the recessed portion 35 by filling a gap generated between the annular opposing surface and the axial end surface in the attached state. An annular protrusion 37 that surrounds the recessed portion 35 is provided on a portion coming into contact with the seal portion 134, of the axial end surface 34a in the attached state.SELECTED DRAWING: Figure 8

Description

[Technical field]

[0001] The present invention relates to a gas generator to be incorporated in an airbag device as an occupant protection device equipped in an automobile or the like. [Background technology]

[0002] Conventionally, airbag devices, which are passenger protection devices, have become widespread from the viewpoint of protecting passengers in automobiles, etc. Airbag devices are installed for the purpose of protecting passengers from impacts that occur when a vehicle or the like crashes, and the airbag instantly inflates and deploys when a vehicle or the like crashes, so that the airbag acts as a cushion to receive the body of the passenger.

[0003] The gas generator is incorporated in the airbag device, and when a vehicle or the like crashes, an igniter is ignited by current from a control unit, and the flame generated in the igniter burns the gas generating agent, instantaneously generating a large amount of gas, thereby inflating and deploying the airbag. Some igniters are held by a holding part that is a resin molded body that the gas generator has.

[0004] The control unit supplies electricity to the igniter by, for example, inserting a male connector of a harness for connecting the igniter and the control unit into a bottomed, generally cylindrical female connector portion provided in the holding portion, thereby connecting to a terminal pin of the igniter. Examples of documents that employ such a method of supplying electricity include JP 2018-190713 A (Patent Document 1) and JP 2015-519245 A (Patent Document 2). [Prior art documents] [Patent documents]

[0005] [Patent Document 1] JP 2018-190713 A [Patent Document 2] Special Publication No. 2015-519245 Summary of the Invention [Problem to be solved by the invention]

[0006] When the above-mentioned current supply method is adopted, it may be necessary to ensure a seal at the interface between the female connector and the male connector. If no measures are taken in this regard, moisture or the like may enter the inside of the female connector from the interface, which may cause a malfunction in the electrical connection between the igniter and the control unit.

[0007] Also, in gas generators, an assembly structure may be adopted in which an inserted male connector is held by a female connector portion by a so-called snap fit, in which a locking protrusion provided on the peripheral surface of the male connector engages with a locking recess provided on the inner peripheral surface of the female connector portion.

[0008] When a female connector part having such a locking recess is manufactured by injection molding, the female connector part will have an undercut. Therefore, when removing the mold from the female connector part to take out the injection molded female connector part from the mold, it is necessary to move the movable part provided in the mold from the undercut. At that time, a parting line as a minute protrusion part is formed on the female connector part corresponding to the parting line between the movable part of the mold and the other parts. Therefore, in some cases, this may become a leak route and reduce the above-mentioned sealing property.

[0009] Therefore, the present invention has been made in consideration of the above-mentioned points, and aims to improve sealing performance with a simple configuration in a gas generator having a female connector portion made of a resin molded body used to energize an igniter. [Means for solving the problem]

[0010] A gas generator according to the present invention includes a housing, an igniter, a male connector, and a female connector portion. The housing has a combustion chamber therein in which a gas generating agent is accommodated. The igniter has an ignition portion loaded with an ignition charge for combusting the gas generating agent, and a terminal pin connected to the ignition portion. The male connector is electrically connected to the igniter. The female connector portion is configured so that the male connector can be inserted and can hold the inserted male connector. The housing has a shelf portion that separates the combustion chamber from a space outside the housing and is a portion to which the igniter is attached, and a cylindrical portion that extends from an outer edge of the shelf portion toward the opposite side to the combustion chamber. The shelf portion is provided with an opening. The igniter is disposed such that the ignition portion is located closer to the combustion chamber than the shelf portion when the terminal pin is inserted through the opening. The female connector portion includes a recessed portion that is located inside the tubular portion and exposed toward the outside along the axial direction of the tubular portion, allowing a portion of the male connector to be inserted therein. The inner peripheral surface of the tubular portion is covered with a resin covering portion. The inner peripheral surface of the recessed portion is defined by the covering portion. A locking protrusion is provided on the peripheral surface of the male connector at a portion that is inserted into the recessed portion. A locking recess capable of locking the locking protrusion is provided on the covering portion at a portion that defines the inner peripheral surface of the recessed portion. The male connector has an annular opposing surface that is an exposed surface of the female connector portion that is exposed toward the outside and that faces at least a portion of an axial end surface that is located so as to surround the recessed portion when the male connector is inserted into the female connector portion. Between the annular opposing surface and the axial end face is interposed a seal portion made of an elastic material which, in the mounted state, is sandwiched between the annular opposing surface and the axial end face and compressed, thereby filling the gap that is generated between the annular opposing surface and the axial end face, thereby liquid-tightly sealing the internal space of the concave portion from the outside.In the gas generator based on the present invention, an annular projection is provided on a portion of the axial end face which contacts the seal portion in the mounted state so as to surround the recessed portion. Effect of the Invention

[0011] According to the present invention, in a gas generator having a female connector portion made of a resin molded body used for energizing an igniter, it is possible to improve sealing performance with a simple configuration. [Brief description of the drawings]

[0012] [Figure 1] 1 is a schematic diagram of a gas generator according to a first embodiment. [Diagram 2] 2A and 2B are a bottom view and a schematic cross-sectional view of the holding part shown in FIG. [Diagram 3] 1A to 1C are a side view, a plan view, a bottom view and a cross-sectional view of a male connector provided in a gas generator according to a first embodiment. [Figure 4] 2A to 2C are schematic cross-sectional views for explaining a manufacturing process of the holding portion shown in FIG. [Diagram 5] 2 is a schematic perspective view of a lower mold used in manufacturing the holding portion shown in FIG. 1. [Figure 6] 2A to 2C are schematic cross-sectional views for explaining a manufacturing process of the holding portion shown in FIG. [Figure 7] 2A to 2C are schematic cross-sectional views for explaining a manufacturing process of the holding portion shown in FIG. [Figure 8] 5A to 5C are schematic cross-sectional views showing the states before and after the male connector is inserted into the female connector portion. [Figure 9] 9 is an enlarged cross-sectional view of the vicinity of the annular projection shown in FIG. 8. [Figure 10] 10 is an enlarged cross-sectional view of the vicinity of an annular projection in a gas generator according to a second embodiment. FIG. [Figure 11] 13 is an enlarged cross-sectional view of the vicinity of the annular projection in a gas generator according to a modified example. FIG. [Figure 12] FIG. 11 is a schematic diagram of a gas generator according to a third embodiment. [Figure 13]13 is an enlarged cross-sectional view of the vicinity of an igniter of the gas generator shown in FIG. 12. [Figure 14] FIG. 11 is a schematic diagram of a gas generator according to a fourth embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0013] Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In the following first and second embodiments, the present invention is applied to a disk-type gas generator that is preferably incorporated in an airbag device mounted on the steering wheel of an automobile. In the following third embodiment, the present invention is applied to a cylinder-type gas generator that is preferably incorporated in a side airbag device, and in the following fourth embodiment, the present invention is applied to a gas generator (so-called micro gas generator) that is preferably incorporated in a seatbelt device equipped with a pretensioner. In the following embodiments, the same or common parts are denoted by the same reference numerals in the drawings, and their description will not be repeated.

[0014] (Embodiment 1) Fig. 1 is a schematic diagram of a gas generator according to embodiment 1. First, with reference to Fig. 1, the configuration of a gas generator 1A according to the present embodiment will be described.

[0015] As shown in Fig. 1, gas generator 1A according to this embodiment has a short, substantially cylindrical housing with one axial end and the other axial end closed. An accommodating space provided inside the housing accommodates internal components such as a retaining portion 30, an igniter 40, a cup-shaped member 50, an enhancer charge 56, a gas generating agent 61, a lower support member 70, an upper support member 80, a cushion material 85, and a filter 90. A combustion chamber 60 is located in the accommodating space provided inside the housing, and mainly accommodates gas generating agent 61 among the above-mentioned internal components.

[0016] The housing includes a lower shell 10 and an upper shell 20 as shell members. Each of the lower shell 10 and the upper shell 20 is a press-formed product formed by, for example, pressing a rolled metal plate-like member. As the metal plate-like member constituting the lower shell 10 and the upper shell 20, for example, a metal plate made of stainless steel, iron steel, aluminum alloy, stainless alloy, etc. is used, and preferably a so-called high-tensile steel plate that does not break or otherwise break even when a tensile stress of 440 MPa or more and 780 MPa or less is applied is used.

[0017] The lower shell 10 and the upper shell 20 are each formed in a generally cylindrical shape with a bottom, and are assembled and joined together with their open faces facing each other to form a housing. The lower shell 10 has a bottom plate portion 11 and a cylindrical portion 12. The upper shell 20 has a top plate portion 21 and a cylindrical portion 22.

[0018] The upper end of the cylindrical portion 12 of the lower shell 10 is inserted into the lower end of the cylindrical portion 22 of the upper shell 20 and press-fitted. Furthermore, the cylindrical portion 12 of the lower shell 10 and the cylindrical portion 22 of the upper shell 20 are joined at or near their abutment, thereby fixing the lower shell 10 and the upper shell 20. For joining the lower shell 10 and the upper shell 20, electron beam welding, laser welding, friction welding, or the like can be suitably used.

[0019] As a result, the portion of the peripheral wall of the housing closer to the bottom plate 11 is formed by the cylindrical portion 12 of the lower shell 10, and the portion of the peripheral wall of the housing closer to the top plate 21 is formed by the cylindrical portion 22 of the upper shell 20. Moreover, one end and the other end in the axial direction of the housing are closed by the bottom plate 11 of the lower shell 10 and the top plate 21 of the upper shell 20, respectively.

[0020] A protruding cylindrical portion 13 is provided at the center of the bottom plate portion 11 of the lower shell 10, protruding toward the top plate portion 21. The protruding cylindrical portion 13 is a portion to which the igniter 40 is fixed via the holding portion 30. The protruding cylindrical portion 13 is formed in a substantially cylindrical shape with a bottom, and has a cylindrical portion 13a and a shelf portion 13b provided at the end of the cylindrical portion 13a on the top plate portion 21 side. The cylindrical portion 13a extends from the outer edge of the shelf portion 13b toward the opposite side to the combustion chamber 60, and the shelf portion 13b separates the combustion chamber 60 from the space outside the housing. The igniter 40, which will be described later, is attached to the shelf portion 13b.

[0021] The shelf portion 13b is provided with an opening 15 having a point-asymmetric shape (for example, a D-shape, a barrel shape, an oval shape, or the like) in a plan view. The opening 15 is a portion through which a pair of terminal pins 42 of the igniter 40 are inserted.

[0022] A recess 14 defined by a cylindrical portion 13a and a shelf portion 13b is formed in the center of the bottom plate portion 11 of the lower shell 10. The recess 14 is a portion that serves as a space for providing a female connector portion 34 including a recessed portion 35 in the holding portion 30.

[0023] The igniter 40 is for generating a flame, and includes an ignition unit 41 and the above-mentioned pair of terminal pins 42. The ignition unit 41 contains therein an ignition charge that ignites and burns to generate a flame when activated, and a resistor for igniting the ignition charge. The pair of terminal pins 42 are connected to the ignition unit 41 for igniting the ignition charge.

[0024] The ignition section 41 comprises a squib cup formed in a cup shape, and a base which closes the open end of the squib cup and through which a pair of terminal pins 42 are inserted and held. A resistor (bridge wire) is attached to connect the tips of the pair of terminal pins 42 inserted into the squib cup, and an ignition charge is loaded into the squib cup so as to surround the resistor or be in close proximity to the resistor.

[0025] The resistor is generally made of nichrome wire, etc. The ignition charge is generally made of ZPP (zirconium potassium perchlorate), ZWPP (zirconium tungsten potassium perchlorate), lead tricinate, etc. The squib cup and base are generally made of metal or plastic.

[0026] When a collision is detected, a predetermined amount of current flows through the resistor via the terminal pin 42. When a predetermined amount of current flows through the resistor, Joule heat is generated in the resistor, and the ignition charge begins to burn. The high-temperature flame generated by the combustion explodes 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 2 milliseconds or less when nichrome wire is used for the resistor.

[0027] The igniter 40 is assembled to the bottom plate portion 11 with the ignition portion 41 positioned closer to the top plate portion 21 than the shelf portion 13b and inserted from the inside of the lower shell 10 so that the terminal pin 42 passes through the opening 15 provided in the shelf portion 13b.

[0028] More specifically, a holding portion 30 made of a resin molded portion is provided around the protruding tube portion 13 provided on the bottom plate portion 11. The igniter 40 is held by the holding portion 30 and fixed to the bottom plate portion 11. The configuration of the holding portion 30 and its periphery will be described in detail later.

[0029] A cup-shaped member 50 is attached to the bottom plate portion 11 so as to cover the protruding tube portion 13, the holding portion 30, and the igniter 40. The cup-shaped member 50 has a generally cylindrical shape with a bottom, the end on the bottom plate portion 11 side being open. The cup-shaped member 50 includes a transfer chamber 55 in which a transfer charge 56 is accommodated. The cup-shaped member 50 is arranged to protrude into a combustion chamber 60 in which a gas generating agent 61 is accommodated, so that the transfer chamber 55 faces the ignition portion 41 of the igniter 40.

[0030] The cup-shaped member 50 has a top wall portion 51 and a side wall portion 52 which define the above-mentioned flame transfer chamber 55, and an extension portion 53 which extends radially outward from the open end side of the side wall portion 52.

[0031] The extension portion 53 is formed to extend along the inner surface of the bottom plate portion 11 of the lower shell 10. In detail, the extension portion 53 has a curved shape to follow the shape of the inner bottom surface of the bottom plate portion 11 at the portion where the protruding tubular portion 13 is provided and in the vicinity thereof, and includes a tip portion 54 extending in a flange shape at its radially outer portion.

[0032] The tip portion 54 of the extension portion 53 is disposed between the bottom plate portion 11 and the lower support member 70 along the axial direction of the housing. As a result, the tip portion 54 is sandwiched between the bottom plate portion 11 and the lower support member 70 along the axial direction of the housing.

[0033] The lower support member 70 is in a state where it is pressed toward the bottom plate portion 11 by the gas generating agent 61, the cushion material 85, the upper support member 80, and the top plate portion 21 arranged above it. Therefore, the tip portion 54 of the extension portion 53 of the cup-shaped member 50 is in a state where it is pressed toward the bottom plate portion 11 by the lower support member 70, and the cup-shaped member 50 is fixed to the bottom plate portion 11. This prevents the cup-shaped member 50 from falling off the bottom plate portion 11, even without using crimping or press-fitting to fix the cup-shaped member 50.

[0034] The cup-shaped member 50 has no openings in either the top wall portion 51 or the side wall portion 52, and surrounds a transfer chamber 55 provided therein. The cup-shaped member 50 bursts or melts in response to a pressure increase in the transfer chamber 55 and conduction of the generated heat when the transfer charge 56 is ignited by the operation of the igniter 40, and has a relatively low mechanical strength.

[0035] For this reason, the cup-shaped member 50 is preferably made of a metal member such as aluminum or an aluminum alloy, or a resin member such as a thermosetting resin represented by epoxy resin, polybutylene terephthalate resin, polyethylene terephthalate resin, polyamide resin (e.g., nylon 6, nylon 66, etc.), polypropylene sulfide resin, polypropylene oxide resin, etc.

[0036] In addition to the above, the cup-shaped member 50 may be made of a metal member having high mechanical strength, such as iron or copper, with an opening in the side wall portion 52, with a sealing tape attached to close the opening. The method of fixing the cup-shaped member 50 is not limited to the above-mentioned fixing method using the lower support member 70, and other fixing methods may be used.

[0037] The transfer charge 56 filled in the transfer chamber 55 is ignited by the flame generated by the operation of the igniter 40, and generates heat particles by burning. The transfer charge 56 is required to be capable of reliably starting the combustion of the gas generating agent 61. For this reason, the transfer charge 56 generally used is a composition made of a metal powder / oxidizer such as B / KNO3, B / NaNO3, Sr(NO3)2, etc., a composition made of titanium hydride / potassium perchlorate, a composition made of B / 5-aminotetrazole / potassium nitrate / molybdenum trioxide, etc.

[0038] The enhancer charge 56 may be in a powder form or may be formed into a predetermined shape using a binder. The enhancer charge 56 formed using a binder may have various shapes, such as granular, cylindrical, sheet, spherical, single-hole cylinder, multi-hole cylinder, tablet, and the like.

[0039] In the space inside the housing, in the space surrounding the portion in which the above-mentioned cup-shaped member 50 is disposed, there is positioned a combustion chamber 60 containing a gas generating agent 61. In detail, as described above, the cup-shaped member 50 is disposed so as to protrude into the combustion chamber 60 formed inside the housing, and the space provided in the portion facing the outer surface of the side wall portion 52 of this cup-shaped member 50 and the space provided in the portion facing the outer surface of the top wall portion 51 form the combustion chamber 60.

[0040] A filter 90 is disposed along the inner circumference of the housing in a space radially surrounding the combustion chamber 60 in which the gas generating agent 61 is accommodated. The filter 90 has a cylindrical shape. The filter 90 is disposed so that its central axis substantially coincides with the axial direction of the housing.

[0041] The gas generating agent 61 is an agent that generates gas by being ignited by thermal particles generated by the operation of the igniter 40 and burning. As the gas generating agent 61, it is preferable to use a non-azide gas generating agent, and the gas generating agent 61 is generally formed as a molded body containing a fuel, an oxidizer, and an additive.

[0042] The fuel may be, for example, a triazole derivative, a tetrazole derivative, a guanidine derivative, an azodicarbonamide derivative, a hydrazine derivative, or a combination of these. In particular, nitroguanidine, guanidine nitrate, cyanoguanidine, 5-aminotetrazole, or the like is preferably used.

[0043] Examples of the oxidizing agent include basic nitrates such as basic copper nitrate, perchlorates such as ammonium perchlorate and potassium perchlorate, and nitrates containing a cation selected from alkali metals, alkaline earth metals, transition metals, and ammonia. Examples of the nitrates that are preferably used include sodium nitrate and potassium nitrate.

[0044] Examples of additives include binders, slag formers, and combustion control agents. Examples of binders that can be suitably used include organic binders such as metal salts of carboxymethylcellulose and stearates, and inorganic binders such as synthetic hydrotalcite and acid clay. Examples of slag formers that can be suitably used include silicon nitride, silica, and acid clay. Examples of combustion control agents that can be suitably used include metal oxides, ferrosilicon, activated carbon, and graphite.

[0045] The shape of the molded body of the gas generating agent 61 may be various, such as granular, pellet-like, cylindrical, or other granular shapes, or disk-like shapes. In addition, 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 according to the specifications of the airbag device in which the gas generator 1A is incorporated, and it is preferable to select an optimal shape according to the specifications, such as a shape in which the gas generation rate changes over time when the gas generating agent 61 is burned. In addition to the shape of the gas generating agent 61, it is preferable to appropriately select the size and filling amount of the molded body taking into consideration the linear burning rate, pressure exponent, etc. of the gas generating agent 61.

[0046] The filter 90 can be made of, for example, metal wire such as stainless steel or steel wound and sintered, or a mesh material woven with metal wires and pressed into a compact shape. Specific examples of the mesh material that can be used include knitted wire mesh, plain woven wire mesh, and an assembly of crimped metal wires.

[0047] Also, a perforated metal plate wound around the filter 90 can be used. In this case, the perforated metal plate can be, for example, an expanded metal plate in which staggered cuts are made in a metal plate and the cuts are expanded to form holes and processed into a mesh-like shape, or a hook metal plate in which holes are made in a metal plate and burrs formed around the holes are crushed and flattened. In this case, the size and shape of the holes can be appropriately changed as necessary, and holes of different sizes and shapes can be included in the same metal plate. In addition, as the metal plate, for example, a steel plate (mild steel) or a stainless steel plate can be suitably used, and a non-ferrous metal plate such as aluminum, copper, titanium, nickel, or an alloy thereof can also be used.

[0048] The filter 90 functions as a cooling means for cooling the gas generated in the combustion chamber 60 by removing the high temperature heat of the gas when the gas passes through the filter 90, and also functions as a removing means for removing residues (slag) and the like contained in the gas. Therefore, in order to sufficiently cool the gas and prevent the residues from being discharged to the outside, it is necessary to ensure that the gas generated in the combustion chamber 60 passes through the filter 90. The filter 90 is disposed away from the cylindrical parts 12, 22 of the upper shell 20 and the cylindrical part 12 of the lower shell 10, which constitute the peripheral wall part of the housing, so that a gap 28 of a predetermined size is formed between the filter 90 and the cylindrical parts 12, 22.

[0049] A plurality of gas outlets 24 are provided in the cylindrical portion 22 of the upper shell 20 in a portion facing the filter 90. The plurality of gas outlets 24 are for leading the gas that has passed through the filter 90 to the outside of the housing.

[0050] Moreover, a metal sealing tape 26 is attached as a sealing member to the inner peripheral surface of the cylindrical portion 22 of the upper shell 20 so as to close the plurality of gas ejection ports 24. As this sealing tape 26, an aluminum foil with an adhesive material applied to one side or the like can be suitably used, and the sealing tape 26 ensures the airtightness of the combustion chamber 60.

[0051] A lower support member 70 is disposed near the end of the combustion chamber 60 on the bottom plate portion 11 side. The lower support member 70 has an annular shape, and is disposed substantially between the filter 90 and the bottom plate portion 11 so as to cover the boundary between the filter 90 and the bottom plate portion 11. As a result, the lower support member 70 is positioned between the bottom plate portion 11 and the gas generating agent 61 near the end of the combustion chamber 60.

[0052] The lower support member 70 has an abutment portion 72 erected so as to abut against the inner peripheral surface of the axial end portion located on the bottom plate portion 11 side of the filter 90, and a bottom portion 71 extended radially inward from the abutment portion 72. The bottom portion 71 is formed so as to extend along the inner bottom surface of the bottom plate portion 11 of the lower shell 10. In detail, the bottom portion 71 has a shape bent so as to follow the shape of the inner bottom surface of the bottom plate portion 11 including the portion where the protruding tubular portion 13 is provided, and includes a tip portion 73 erected on the radially inner portion.

[0053] The lower support member 70 functions as an outflow prevention means for preventing gas generated in the combustion chamber 60 from outflowing through the gap between the lower end of the filter 90 and the bottom plate portion 11 during operation without passing through the inside of the filter 90. The lower support member 70 is formed, for example, by pressing a metal plate-like member, and is preferably made of a member made of a steel plate such as ordinary steel or special steel (for example, a cold-rolled steel plate or a stainless steel plate).

[0054] Here, the tip 54 of the extension 53 of the cup-shaped member 50 described above is sandwiched and held between the bottom plate 11 and the bottom 71 along the axial direction of the housing. By configuring in this manner, the cup-shaped member 50 is fixed to the bottom plate 11 with the tip 54 of the extension 53 being pressed toward the bottom plate 11 by the bottom 71 of the lower support member 70.

[0055] An upper support member 80 is disposed at the end of the combustion chamber 60 located on the top plate portion 21 side. The upper support member 80 has a substantially disk-like shape, and is disposed between the filter 90 and the top plate portion 21 so as to cover the boundary between the filter 90 and the top plate portion 21. As a result, the upper support member 80 is positioned between the top plate portion 21 and the gas generating agent 61 in the vicinity of the end of the combustion chamber 60.

[0056] The upper support member 80 has a bottom portion 81 that abuts against the top plate portion 21, and an abutment portion 82 that stands upright from the periphery of the bottom portion 81. The abutment portion 82 abuts against the inner peripheral surface of the axial end portion of the filter 90 that is located on the top plate portion 21 side.

[0057] The upper support member 80 functions as an outflow prevention means for preventing gas generated in the combustion chamber 60 from outflowing through the gap between the upper end of the filter 90 and the top plate portion 21 during operation without passing through the inside of the filter 90. The upper support member 80, like the lower support member 70, is formed, for example, by pressing a metal plate-like member, and is preferably made of a member made of a steel plate such as ordinary steel or special steel (for example, a cold-rolled steel plate or a stainless steel plate).

[0058] An annular cushioning material 85 is disposed inside the upper support member 80 so as to come into contact with the gas generating agent 61 contained in the combustion chamber 60. As a result, the cushioning material 85 is positioned between the top plate portion 21 and the gas generating agent 61 in the portion of the combustion chamber 60 on the top plate portion 21 side, and presses the gas generating agent 61 toward the bottom plate portion 11 side.

[0059] The cushioning material 85 is provided for the purpose of preventing the gas generating agent 61 made of a molded body from being crushed by vibration, etc. The cushioning material 85 is preferably made of a member made of a ceramic fiber molded body, rock wool, foamed resin (for example, foamed silicone, foamed polypropylene, foamed polyethylene, etc.), rubber represented by chloroprene and EPDM, etc.

[0060] Fig. 2(A) is a bottom view of the holding part shown in Fig. 1. Fig. 2(B) is a schematic cross-sectional view taken along line IIB-IIB shown in Fig. 2(A). Next, a detailed configuration of the holding part 30 according to this embodiment will be described with reference to Fig. 2 and the above-mentioned Fig. 1.

[0061] 1 and 2, the holding portion 30, which serves as a covering portion that covers the inner peripheral surface of the tube portion 13a as described later, is made of a resin molded portion formed by injection molding (more specifically, insert molding) using a mold. The holding portion 30 is formed by adhering an insulating fluid resin material to the bottom plate portion 11 so as to reach from a part of the inner surface to a part of the outer surface of the bottom plate portion 11 through an opening 15 provided in the bottom plate portion 11 of the lower shell 10, and then solidifying the material.

[0062] The retaining portion 30 has an inner covering portion 31 covering part of the inner surface of the bottom plate portion 11 of the lower shell 10, an outer covering portion 32 covering part of the outer surface of the bottom plate portion 11 of the lower shell 10, and a connecting portion 33 located within an opening 15 provided in the bottom plate portion 11 of the lower shell 10 and continuous with the inner covering portion 31 and the outer covering portion 32, respectively.

[0063] The retaining portion 30 is fixed to the bottom plate portion 11 at the surfaces of the inner covering portion 31, the outer covering portion 32, and the connecting portion 33 facing the bottom plate portion 11. More specifically, the inner covering portion 31 is fixed to the inner surface of the shelf portion 13b. The outer covering portion 32 includes a portion that covers the inner peripheral surface of the tube portion 13a, and is fixed to the inner peripheral surface of the tube portion 13a and the outer surface of the shelf portion 13b. The connecting portion 33 is fixed to the surface of the bottom plate portion 11 at a portion that defines the opening 15.

[0064] Moreover, the inner covering portion 31 is fixed to the side and bottom surfaces of the portions of the ignition portion 41 of the igniter 40 near the lower end, and to the surface of the portion of the terminal pin 42 of the igniter 40 near the upper end. The outer covering portion 32 is fixed to the surface of the portion of the terminal pin 42 near the upper end.

[0065] As a result, the opening 15 is closed by the pair of terminal pins 42 and the holding portion 30, and the sealing performance at this portion is ensured, thereby ensuring airtightness of the space inside the housing. As described above, the opening 15 is formed in an asymmetrical shape in a plan view. Therefore, by embedding the opening 15 with the connecting portion 33, the opening 15 and the connecting portion 33 also function as a rotation prevention mechanism that prevents the holding portion 30 from rotating relative to the bottom plate portion 11.

[0066] A pair of through holes 36 are provided through the inner covering portion 31, the outer covering portion 32 and the connecting portion 33. The pair of through holes 36 are portions through which a pair of terminal pins 42 are inserted.

[0067] The outer covering portion 32 has a female connector portion 34 located in a recess 14 provided in the bottom plate portion 11 of the lower shell 10. The female connector portion 34 is configured so that the male connector 130 can be inserted therein and can hold the inserted male connector 130.

[0068] The female connector portion 34 is located inside the cylindrical portion 13a and includes a recessed portion 35 that is exposed to the outside along the axial direction of the cylindrical portion 13a.

[0069] A portion of the terminal pin 42 of the igniter 40 near the lower end is exposed and disposed in the recessed portion 35. A male connector 130, which will be described later, is inserted into the recessed portion 35, thereby achieving electrical continuity between the core wire of the harness and the terminal pin 42.

[0070] The inner circumferential surface 35a of the recessed portion 35 is provided with a plurality of locking recesses 35a1 capable of locking the locking protrusions 136 provided on the male connector 130. In this embodiment, three locking recesses 35a1 of the same shape are arranged at rotationally symmetric positions of 120° when viewed along the axial direction of the holding portion 30.

[0071] An axial end surface 34a of the female connector portion 34 is an exposed surface that is exposed to the outside, and is positioned so as to surround the recessed portion 35. An annular protrusion 37 that is substantially circular in plan view is provided on the axial end surface 34a. The details of the annular protrusion 37 will be described later.

[0072] An inner bottom surface 35b of the recessed portion 35 includes, at its center, a protrusion 39 that is substantially T-shaped in plan view. The protrusion 39 is provided with a through hole 36 through which the terminal pin 42 is inserted.

[0073] As the raw material of the holding part 30 formed by injection molding, a resin material having excellent heat resistance, durability, corrosion resistance, etc. after hardening is suitably selected and used. In this case, it is possible to use not only thermosetting resins such as epoxy resins, but also 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, etc. When these thermoplastic resins are selected as raw materials, it is preferable to include glass fiber or the like as a filler in these resin materials in order to ensure the mechanical strength of the holding part 30 after molding. However, if sufficient mechanical strength can be ensured with only the thermoplastic resin, it is not necessary to add the above-mentioned filler.

[0074] The above-mentioned injection molding may be performed using the lower shell 10 in which an adhesive layer is provided in advance at a predetermined position on the surface of the bottom plate portion 11 in the portion that will be covered by the holding portion 30. The adhesive layer can be formed by applying adhesive to a predetermined position on the bottom plate portion 11 in advance and curing the adhesive.

[0075] In this way, the hardened adhesive layer is positioned between the bottom plate portion 11 and the holding portion 30. Therefore, it is possible to more firmly fix the holding portion 30, which is made of a resin molded portion, to the bottom plate portion 11. Therefore, if the adhesive layer is provided in an annular shape along the circumferential direction so as to surround the opening 15 provided in the bottom plate portion 11, it is possible to ensure higher sealing performance in that portion.

[0076] As the adhesive to be applied in advance to the bottom plate portion 11, an adhesive containing as a raw material a resin material that has excellent heat resistance, durability, corrosion resistance, etc. after hardening is preferably used, and for example, an adhesive containing as a raw material a cyanoacrylate-based resin or a silicone-based resin is particularly preferably used. In addition to the above-mentioned resin materials, phenol-based resins, epoxy-based resins, melamine-based resins, urea-based resins, polyester-based resins, alkyd-based resins, polyurethane-based resins, polyimide-based resins, polyethylene-based resins, polypropylene-based resins, polyvinyl chloride-based resins, polystyrene-based resins, polyvinyl acetate-based resins, polytetrafluoroethylene-based resins, acrylonitrile butadiene styrene-based resins, acrylonitrile styrene-based resins, acrylic resins, polyamide-based resins, polyacetal-based resins, polycarbonate-based resins, polyphenylene ether-based resins, polybutylene terephthalate-based resins, polyethylene terephthalate-based resins, polyolefin-based resins, polyphenylene sulfide-based resins, polysulfone-based resins, polyethersulfone-based resins, polyarylate-based resins, polyether ether ketone-based resins, polyamide imide-based resins, liquid crystal polymers, styrene-based rubbers, olefin-based rubbers, and the like can be used as the above-mentioned adhesives.

[0077] Figures 3(A) to 3(C) are respectively a side view, a plan view, and a bottom view of the male connector provided in the gas generator according to embodiment 1. Figure 3(D) is a schematic cross-sectional view taken along line IIID-IIID shown in Figure 3(B). Next, a detailed configuration of male connector 130 according to this embodiment will be described with reference to Figure 3.

[0078] 3, male connector 130 has a barrel-shaped main body 131, an opposing portion 132, and a cable 133. Male connector 130 constitutes a part of a harness for connecting igniter 40 and a control unit (not shown) serving as an external power source.

[0079] The main body 131 is a portion that is inserted into the recessed portion 35 of the female connector portion 34, and is composed of a pair of terminal blades 131a that can receive each of the pair of terminal pins 42. The facing portion 132 is a portion that is attached to one end of the main body 131. A part of the facing portion 132 includes an annular facing surface 132a that faces a part of the axial end surface 34a of the female connector portion 34 in a state in which the male connector 130 is inserted into the female connector portion 34 (hereinafter, this state will also be referred to as the attached state). The cable 133 extends outward from the facing portion 132 when viewed along the axial direction of the main body 131.

[0080] A locking protrusion 136 protruding outward from the peripheral surface 131c of the main body 131 at the portion inserted into the recessed portion 35 is provided. In the attached state, the locking protrusion 136 is locked in a locking recess 35a1 on the inner peripheral surface 35a of the recessed portion 35. As a result, the male connector 130 is assembled to the female connector portion 34 by a so-called snap fit consisting of the locking protrusion 136 and the locking recess 35a1.

[0081] The number of locking projections 136 is not particularly limited as long as it is the same as the number of locking recesses 35a1, and may be one or more. In this embodiment, three locking projections 136 having the same hook shape are arranged at rotationally symmetric positions of 120° when viewed along the axial direction of main body 131.

[0082] A substantially annular seal portion 134 is provided on the circumferential surface 131c of the main body portion 131. The seal portion 134 is for liquid-tightly sealing the internal space of the recessed portion 35 from the outside. There are no particular limitations on the material of the seal portion 134 as long as it is elastic. In the present embodiment, the seal portion 134 is made of rubber.

[0083] A recess 131d having a generally T-shape in plan view, similar to the protrusion 39, is provided in a portion of the main body 131 that faces the inner bottom surface 35b of the recess 35 in the attached state. When the main body 131 is inserted into the recess 35, the protrusion 39 fits into the recess 131d. Since the protrusion 39 and the recess 131d have a generally T-shape in plan view, the orientation of the male connector 130 in a direction perpendicular to the insertion direction of the male connector 130 into the female connector portion 34 is regulated by the protrusion 39 and the recess 131d.

[0084] Next, the operation of gas generator 1A in the present embodiment described above will be described with reference to Fig. 1. Note that the operation described below is performed after male connector 130 is inserted into recessed portion 35 of female connector portion 34 of holding portion 30 and connected to igniter 40 (see Fig. 4 described later).

[0085] When a vehicle equipped with gas generator 1A according to this embodiment collides, the collision is detected by collision detection means separately provided in the vehicle, and based on this, igniter 40 is activated by current from a control unit separately provided in the vehicle. Transfer charge 56 accommodated in transfer charge chamber 55 is ignited by a flame generated by the activation of igniter 40 and burns, generating a large amount of thermal particles. Cup-shaped member 50 bursts or melts due to the combustion of transfer charge 56, and the above-mentioned thermal particles flow into combustion chamber 60.

[0086] The gas generating agent 61 contained in the combustion chamber 60 is ignited and burned by the flowing hot particles, generating a large amount of gas. The gas generated in the combustion chamber 60 passes through the inside of the filter 90, during which time the heat is removed by the filter 90 and the gas is cooled, and the slag contained in the gas is removed by the filter 90 and flows into the gap 28.

[0087] As the pressure in the space inside the housing rises, the sealing tape 26 closing the gas outlet 24 provided in the upper shell 20 breaks, and gas is ejected to the outside of the housing through the gas outlet 24. At that time, the multiple gas outlets 24 are opened in stages, and the ejected gas is introduced into the airbag provided adjacent to the gas generator 1A, inflating and deploying the airbag.

[0088] Figures 4, 6 and 7 are schematic views for illustrating a manufacturing process of a holding portion provided in the gas generator according to embodiment 1. Figure 5 is a schematic perspective view of a lower mold used in manufacturing the holding portion. Next, with reference to Figures 4 to 7, a manufacturing method of holding portion 30 provided in gas generator 1A according to the present embodiment will be described. Note that Figures 4, 6 and 7 show cross-sectional views of holding portion 30 etc. corresponding to Figure 2(B).

[0089] First, as shown in Fig. 4, the housing is set in lower die 101. Next, prefabricated igniter 40 is set in lower die 101 from the inside of lower shell 10 so that terminal pin 42 is inserted into opening 15 provided in protruding cylindrical portion 13 of lower shell 10. Next, upper die 100 for injection molding is set.

[0090] Here, in the holding part 30 as a resin molded part manufactured by injection molding, the inner peripheral surface 35a of the concave part 35 of the female connector part 34 is provided with the locking recess 35a1 as an undercut (see FIG. 2, etc.). Therefore, in this embodiment, a so-called slide core mechanism is adopted in the lower mold 101 in order to provide the locking recess 35a1 as an undercut.

[0091] As shown in Figs. 4 and 5, the lower die 101 has a fixed portion 102 and a plurality of movable core portions 103. The fixed portion 102 includes a fixed core portion 102a and a peripheral portion 102b. The fixed core portion 102a is a portion located at the center of the lower die 101. The plurality of movable core portions 103 are portions configured to be movable in a predetermined direction. The peripheral portion 102b is a portion located so as to surround the plurality of movable core portions 103. An annular recess 102b1 is provided on the end face of the peripheral portion 102b on the upper die 100 side. The annular protrusion 37 of the female connector portion 34 is formed at a position corresponding to this annular recess 102b1.

[0092] The fixed core part 102a is provided with a receiving part for receiving the terminal pin 42. In addition, a pocket part 104 for accommodating the movable core part 103, which slides toward the fixed core part 102a as described later, is provided on the peripheral surface of the fixed core part 102a in a portion facing the movable core part 103.

[0093] The multiple movable core parts 103 are intended to provide locking recesses 35a1 as undercuts on the inner circumferential surface 35a of the recessed part 35 of the female connector part 34. In this embodiment, three movable core parts 103 corresponding to the number of locking recesses 35a1 are arranged at rotationally symmetric positions of 120° when viewed along the axial direction of the fixed core part 102a. Note that two of these three movable core parts 103 are shown in Figs. 4 and 5.

[0094] A protrusion 103a protruding outward from a portion of the side surface of the movable core portion 103 facing the cylindrical portion 13a of the protruding cylindrical portion 13 is provided in the portion. The locking recess 35a1 is formed at a position corresponding to the protrusion 103a.

[0095] The movable core part 103 has a portion located closer to the upper die 100 than the peripheral part 102b and exposed to the outside, and the other portion is housed inside the fixed part 102.

[0096] Next, a fluid resin material is poured between the upper mold 100 and the lower mold 101 through a gate 100a for injecting the fluid resin material provided in the upper mold 100. This forms the holding portion 30 made of a resin molded portion, as shown in Fig. 6. The igniter 40 is fixed to the bottom plate portion 11 through the holding portion 30 thus formed.

[0097] Next, as shown in FIG. 7, the movable core part 103 is moved so that the protrusions 103a of the movable core part 103 are removed from the locking recesses 35a1 of the recessed part 35.

[0098] More specifically, the movable core portion 103 is slid toward the fixed core portion 102a. The slid movable core portion 103 is housed in the pocket portion 104 provided on the peripheral surface of the fixed core portion 102a.

[0099] Next, upper die 100 and lower die 101 are released from holding portion 30. Through the above steps, the manufacture of holding portion 30 included in gas generator 1A is completed.

[0100] Fig. 8(A) and Fig. 8(B) are schematic cross-sectional views showing the states before and after the male connector is inserted into the female connector portion, respectively. Fig. 9 is an enlarged cross-sectional view of region IX in Fig. 8(B). Next, with reference to Figs. 8 and 9, the assembly of the male connector 130 to the female connector portion 34 in this embodiment will be described.

[0101] As shown in Figures 8 and 9, male connector 130 is assembled to female connector portion 34 by snap-fitting locking protrusion 136 of main body portion 131 with locking recess 35a1 of recess 35, with main body portion 131 inserted into recess 35 of female connector portion 34.

[0102] In this state, the seal portion 134 provided on the main body portion 131 is interposed between the annular opposing surface 132a of the male connector 130 and the axial end surface 34a of the female connector portion 34, and is compressed by being sandwiched between them. In this way, the seal portion 134 fills the gap generated between the annular opposing surface 132a and the axial end surface 34a, thereby making it possible to liquid-tightly seal the internal space of the recessed portion 35 from the outside.

[0103] In this embodiment, as described above, the annular protrusion 37 is provided on the axial end surface 34a of the female connector portion 34. The annular protrusion 37 is provided so as to surround the recessed portion 35 at a portion that comes into contact with the seal portion 134 in the attached state.

[0104] With this configuration, the seal portion 134 is locally and strongly crushed and compressed at the portion that contacts the annular projection 37. This makes it possible to dramatically improve the sealing performance at that portion.

[0105] Therefore, by being configured as described above, in a gas generator having a female connector portion made of a resin molded body used for energizing an igniter, it is possible to improve sealing performance with a simple configuration.

[0106] Furthermore, in gas generator 1A of this embodiment, when viewed along the axial direction of female connector portion 34, the outer edge of seal portion 134 and the outer edge of annular opposing surface 132a are located outside the outer edge of annular protrusion 37.

[0107] By configuring in this manner, seal portion 134 comes into pressure contact with all of the tip surface, inner circumferential surface, and outer circumferential surface of annular projection 37. As a result, a large sealing area between seal portion 134 and annular projection 37 can be secured, which also enables the sealing performance of gas generator 1A to be dramatically improved.

[0108] Furthermore, as described above, retaining portion 30 used in gas generator 1A according to the present embodiment is provided with locking recess 35a1 as an undercut (see FIG. 2, etc.). For this reason, in the present embodiment, in molding this, a slide core mechanism consisting of lower die 101 divided into fixed portion 102 and movable core portion 103 is employed as lower die 101. When injection molding is performed using a mold divided in this manner, a minute protrusion portion called a parting line is formed in the molded product at a portion corresponding to the parting line between the dies.

[0109] 5(B), in this embodiment, parting lines PL are formed in the retaining portion 30 at the dividing line between the fixed core portion 102a and the movable core portion 103, the dividing line between the peripheral portion 102b and the movable core portion 103, and the dividing line between the fixed core portion 102a and the peripheral portion 102b (see dashed lines in the figure). Of these, if the parting line PL is formed in the retaining portion 30 at the portion corresponding to the dividing line between the fixed core portion 102a and the movable core portion 103, leakage may occur along the parting line, resulting in a deterioration in sealing performance (see arrows in the figure).

[0110] In this regard, in gas generator 1A according to the present embodiment, annular protrusion 37 is provided at a position outside the parting line PL of that portion (i.e., a position corresponding to annular recess 102b1 in the figure). This results in a portion where seal portion 134 is locally and strongly crushed and compressed, as described above, being located at a position outside the parting line PL of that portion. Therefore, this also enables the sealing performance of gas generator 1A to be improved.

[0111] In the above embodiment, the case where seal portion 134 constitutes a part of male connector 130 has been described as an example, but seal portion 134 may be provided as a separate body from male connector 130. In this case, male connector 130 may be inserted into female connector portion 34 with the separate seal portion positioned relative to annular opposing surface 132a of male connector 130 or axial end surface 34a of female connector portion 34, thereby assembling them.

[0112] In addition, in the above-described embodiment, an example has been given of a case in which a slide core mechanism is adopted in the lower die 101 in order to provide the locking recess 35a1 as an undercut on the inner surface 35a of the concave portion 35, but a so-called inclined core mechanism may also be adopted in the lower die 101.

[0113] Furthermore, in the present embodiment described above, an example has been given of the case in which annular projection 37 of female connector portion 34 is formed by providing annular recess 102b1 on the end face of peripheral portion 102b, but annular projection 37 may be configured by a parting line formed in retaining portion 30 in a portion corresponding to the parting line between peripheral portion 102b and movable core portion 103 and the parting line between fixed core portion 102a and peripheral portion 102b when molding retaining portion 30 as a resin molded portion. Even in this case, the sealing performance of gas generator 1A can be improved.

[0114] Furthermore, when configured in this manner, the amount of resin used in molding retaining portion 30 can be reduced compared to when annular protrusion 37 is formed by providing annular recess 102b1. Furthermore, even when configured in this manner, annular protrusion 37 is positioned outside parting line PL formed in retaining portion 30 in a portion corresponding to the dividing line between fixed core portion 102a and movable core portion 103, and therefore the sealing performance of gas generator 1A can be improved as described above.

[0115] (Embodiment 2) Figure 10 is an enlarged cross-sectional view of the vicinity of the annular projection in a gas generator according to embodiment 2. Gas generator 1B according to the present embodiment will be described below with reference to Figure 10. Note that Figure 10 shows portions of female connector portion 34B and male connector 130 according to the present embodiment that correspond to female connector portion 34 and male connector 130 shown in Figure 9 (the same applies to Figure 11 described later).

[0116] As shown in FIG. 10, gas generator 1B according to the present embodiment differs from gas generator 1A according to embodiment 1 described above in the configuration of annular projection 37B provided on axial end face 34a of female connector portion 34B.

[0117] More specifically, in gas generator 1B of this embodiment, when viewed along the axial direction of female connector part 34B, annular protrusion 37B has protruding portion 38 that protrudes outward beyond the outer edge of annular opposing surface 132a.

[0118] Even when configured in this manner, effects similar to those described in the above-mentioned first embodiment can be obtained, and in a gas generator having a female connector portion made of a resin molded body used to energize the igniter, it is possible to improve sealing performance with a simple configuration.

[0119] Furthermore, when configured in this manner, the tip surface of annular projection 37B can be configured to be considerably large. Therefore, by specifying the position, shape, and the like of the tip surface of annular projection 37B, it becomes possible to easily determine the phase of gas generator 1B during image inspection performed as an appearance inspection of gas generator 1B, or when gas generator 1B is set in a jig in the manufacturing process of gas generator 1B, etc. This makes it possible to improve the manufacturing efficiency of gas generator 1B.

[0120] Furthermore, in the manufacturing process of gas generator 1B, tape may be affixed to axial end face 34a of female connector portion 34B to prevent foreign matter from entering female connector portion 34B until male connector 130 is inserted into female connector portion 34B. Therefore, by configuring the tip face of annular projection 37B to be considerably large as described above, the tip face can also be used as a receiving surface for affixing tape.

[0121] Furthermore, a vibration resistance test may be required to be performed as one of the performance tests on manufactured gas generator 1B. This test is performed in an attached state in which male connector 130 is inserted into female connector portion 34B of gas generator 1B, and if the tip face of annular projection 37B is small, the load applied to seal portion 134 will be concentrated at that portion, which may result in damage to seal portion 134. In this regard, in the present embodiment, the tip face of annular projection 37B is configured to be considerably large. This makes it possible to distribute the load applied to seal portion 134, thereby effectively suppressing damage to seal portion 134.

[0122] (Modification) Fig. 11 is an enlarged cross-sectional view of the vicinity of the annular projection in a gas generator according to a modified example. Hereinafter, a gas generator 1B1 according to a modified example based on the above-mentioned embodiment 2 will be described with reference to Fig. 11.

[0123] As shown in FIG. 11, a gas generator 1B1 according to the modified example differs from gas generator 1B according to embodiment 2 described above in that the configuration of annular projection 37B1 provided on axial end face 34a of female connector portion 34B1 is different.

[0124] More specifically, in gas generator 1B1 according to this modification, an annular step portion is provided on the inner edge side of annular projection 37B1. As a result, annular projection 37B1 includes a first annular surface 37a located on the inner edge side, a second annular surface 37b located on the outer edge side and closer to annular opposing surface 132a than the first annular surface 37a, and a third annular surface 37c connecting first annular surface 37a and second annular surface 37b. The outer edge of seal portion 134 abuts against third annular surface 37c.

[0125] Even when configured in this manner, effects similar to those described in the above-mentioned embodiment can be obtained, and in a gas generator having a female connector portion made of a resin molded body used to energize the igniter, it is possible to improve sealing performance with a simple configuration.

[0126] Furthermore, when configured in this manner, sealing can also be achieved at the portion where the outer edge of seal portion 134 abuts against third annular surface 37c. As a result, the sealing performance of gas generator 1B1 is improved.

[0127] Furthermore, in this configuration, the outer edge of the seal portion 134 is positioned in the radial direction by the third annular surface 37c. Therefore, when the seal portion 134 is sandwiched between the annular opposing surface 132a of the male connector 130 and the axial end surface 34a of the female connector portion 34B1, the outer edge of the seal portion 134 cannot extend outward beyond the third annular surface 37c.

[0128] This allows the portion of seal portion 134 that comes into contact with the tip surface of annular projection 37B1 (more specifically, first annular surface 37a) to be placed in a more strongly compressed state, compared to a case in which the outer edge of seal portion 134 is not positioned. This allows the sealing performance of gas generator 1B1 to be further improved.

[0129] (Embodiment 3) Fig. 12 is a schematic diagram of a gas generator according to embodiment 3. Fig. 13 is an enlarged cross-sectional view of the vicinity of an igniter of the gas generator shown in Fig. 12. Hereinafter, a gas generator 1C according to the present embodiment will be described with reference to Figs. 12 and 13. Gas generator 1C is a cylinder-type gas generator incorporated in a side airbag device.

[0130] 12, gas generator 1C according to the present embodiment has a long cylindrical outer shape, and has a long cylindrical housing with one end and the other end located in the axial direction closed. The housing includes housing main body 310, holding portion assembly 320, and closing member 330.

[0131] The housing, which is constituted by the housing main body 310, the holding portion assembly 320, and the closing member 330, contains internal components such as an igniter 340, a partition member 350, a gas generating agent 360, a coil spring 370, and a filter 380. Also, the housing contains a combustion chamber S1 in which the gas generating agent 360, one of the internal components described above, is mainly disposed, and a filter chamber S2 in which the filter 380 is disposed.

[0132] The housing body 310 constitutes the peripheral wall of the housing and is made of a long cylindrical member with openings formed on both axial ends. The housing body 310 is made of a metal member such as stainless steel, steel, aluminum alloy, stainless alloy, or the like.

[0133] The holding portion assembly 320 is made of a tubular member having a through-hole-like hollow opening extending in a direction parallel to the axial direction of the housing body 310, and has a holding portion 320A and a connector portion 320B, which will be described later. The holding portion assembly 320 is fixed to the housing body 310 by crimping. The blocking member 330 has a cup-like shape, and is fixed to the housing body 310 by crimping.

[0134] Holding portion 320A and blocking member 330 of holding portion assembly 320 are made of metal members such as stainless steel. Connector portion 320B of holding portion assembly 320 is made of nylon-based resin, for example.

[0135] A partition member 350 is disposed at a predetermined position in the space inside the housing. The partition member 350 is a member for dividing the space inside the housing in the axial direction into a combustion chamber S1 and a filter chamber S2. The partition member 350 has a cylindrical shape with a bottom, and is made of a metal member such as stainless steel.

[0136] Of the space inside the housing, a space sandwiched between the holding portion assembly 320 and the partition member 350 (i.e., the combustion chamber S1) contains a gas generating agent 360 and a coil spring 370. The coil spring 370 is provided for the purpose of preventing the gas generating agent 360 made of a molded body from being crushed by vibration or the like.

[0137] A portion of housing body 310 that defines filter chamber S2 is provided with a plurality of gas outlets 311 arranged in the circumferential and axial directions. Gas that has passed through filter 380 passes through these gas outlets 311 and is then discharged to the outside of the housing.

[0138] As described above, the holder assembly 320 has the metal holder 320A located on the combustion chamber S1 side, and the resin connector 320B located on the opposite side to the combustion chamber S1 side.

[0139] Holding portion 320A is composed of a flat, substantially disk-shaped member having a through-hole as an opening extending axially in the center thereof, and includes a cylindrical first body portion 321 and annular protrusion 322 protruding outward from the outer circumferential surface of the end portion on the combustion chamber S1 side of first body portion 321. In this embodiment, holding portion 320A forms a shelf portion, and a portion of housing main body 310 located closer to connector portion 320B than annular protrusion 322 forms a cylindrical portion.

[0140] Holding portion 320A is inserted into housing body 310 so that its axial direction is parallel to the axial direction of housing body 310. As a result, a through portion provided in holding portion 320A defines a part of a hollow opening of holding portion assembly 320.

[0141] The holding portion 320A defines a combustion chamber S1 provided inside the housing main body 310. The holding portion 320A is also a member for receiving and holding the igniter 340. The holding portion 320A has a concave-shaped accommodation portion 323a at an end portion on the combustion chamber S1 side in the axial direction in order to receive the igniter 340. The accommodation portion 323a communicates with a through portion provided in the holding portion 320A. The igniter 340 is fixed to the holding portion 320A with its base portion 341 accommodated in the accommodation portion 323a. As a result, the ignition portion 342 of the igniter 340 is located closer to the combustion chamber S1 side than the holding portion 320A as a shelf portion.

[0142] Connector portion 320B, together with an end portion of first body portion 321 of holding portion 320A on the connector portion 320B side, constitutes a female connector portion that receives male connector 130 that is connected to terminal pin 343 of igniter 340. Terminal pin 343 is arranged inside connector portion 320B.

[0143] Connector portion 320B is configured as a substantially cylindrical member having a through portion extending in the axial direction at its center. Connector portion 320B includes a cylindrical second body portion 324, a cylindrical portion 325 extending from one axial end of second body portion 324 toward combustion chamber S1 along the axial direction, and a flange portion 326 provided at the other axial end of second body portion 324.

[0144] Second body 324 covers the inner circumferential surface of a portion of housing body 310 that is located closer to connector portion 320B than annular protrusion 322. An engaging recess 324a1 capable of engaging engaging protrusion 136 of male connector 130 is provided on inner circumferential surface 324a of second body 324. An annular protrusion 327 is provided on axial end face 326d of flange portion 326 that is located on the opposite side to combustion chamber S1.

[0145] A portion of connector portion 320B is inserted into housing body 310 so that its axial direction is parallel to the axial direction of housing body 310. More specifically, a portion of connector portion 320B, excluding flange portion 326, is inserted into the open end of housing body 310. Flange portion 326 abuts against the axial end face of housing body 310 outside of housing body 310. As a result, the through portion provided in connector portion 320B defines a portion of the hollow opening of holding portion assembly 320.

[0146] The above-mentioned holding portion 320A is fixed by being press-fitted into the connector portion 320B. As a result, the first body portion 321 and the cylindrical portion 325 are in pressure contact with each other, and thus the holding portion 320A and the connector portion 320B are fixed so as not to easily come apart.

[0147] In the present embodiment, second body 324 of connector part 320B constitutes a covering part. Also, second body 324 and flange part 326 of connector part 320B and an end part of first body 321 of holding part 320A on the connector part 320B side constitute a recessed part of the female connector part.

[0148] The gas generator 1C generates gas by the activation of the igniter 340. More specifically, the activation of the igniter 340 burns the ignition charge or, in addition, the transfer charge, and the pressure in the ignition section 342 rises. This causes the squib cup of the ignition section 342 to break open, and thermal particles generated by the combustion of the ignition charge or, in addition, the transfer charge flow out to the outside of the ignition section 342. The thermal particles flowing out from the ignition section 342 are given directionality by the coil spring 370. As a result, the thermal particles reach the gas generating agent 360 contained in the combustion chamber S1 and burn it. As a result, a large amount of gas is generated in the combustion chamber S1.

[0149] As a result, the pressure in the combustion chamber S1 rises, causing a break in the portion of the partition member 350 where the scores are provided, and the combustion chamber S1 and the filter chamber S2 become connected to each other. The gas generated in the combustion chamber S1 flows into the filter chamber S2. The gas that flows into the filter chamber S2 flows in the axial direction through the hollow portion of the filter 380, then changes direction in the radial direction and flows through the inside of the filter 380.

[0150] The gas after passing through filter 380 is ejected to the outside of the housing through gas ejection port 311 provided in housing main body 310. The ejected gas is introduced into an airbag provided adjacent to gas generator 1C, and inflates and deploys the airbag.

[0151] Even when configured in this manner, effects similar to those described in the above-mentioned first embodiment can be obtained, and in a gas generator having a female connector portion made of a resin molded body used to energize the igniter, it is possible to improve sealing performance with a simple configuration.

[0152] (Embodiment 4) Fig. 14 is a schematic diagram of a gas generator according to embodiment 4. Hereinafter, a gas generator 1D according to the present embodiment will be described with reference to Fig. 14. Gas generator 1D is a micro gas generator that is suitably incorporated in a seat belt device equipped with a pretensioner.

[0153] Gas generator 1D includes igniter assembly 470 having a substantially cylindrical outer shape composed of housing main body 410, igniter 420, and resin molded portion 430, a substantially cylindrical cup 440 with a bottom, and gas generating agent 450. In gas generator 1D, cup 440 is arranged coaxially with igniter assembly 470 and assembled thereto, whereby housing main body 410 and resin molded portion 430 of igniter assembly 470, and cup 440 form a housing that serves as the outer shell of gas generator 1D.

[0154] The housing body 410 includes a cylindrical body 411 and a substantially disk-shaped partition wall 412 located inside the body 411 and at the axial end of the body 411 on the cup 440 side. A through hole 410c is located at the center of the partition wall 412 as an opening. A recess 414 is located inside the body 411 and at the axial end of the body 411 opposite to the cup 440 side. The through hole 410c and the recess 414 communicate with each other. The housing body 410 has a first end surface 410a which is an axial end surface facing the cup 440, and a second end surface 410b which is an axial end surface not facing the cup 440. The housing body 410 is formed of a molded product made of a metal material such as aluminum.

[0155] In this embodiment, a portion of body 411 located on the opposite side to cup 440 as viewed from partition 412 constitutes a cylindrical portion, and partition 412 constitutes a shelf portion.

[0156] The resin molded portion 430 is formed by injection molding (more specifically, insert molding) using a mold. The resin molded portion 430 is formed by attaching an insulating fluid resin material to the housing main body 410 so as to reach from a part of the first end face 410a to a part of the second end face 410b of the housing main body 410 via the through-hole 410c provided in the partition portion 412, and solidifying the material. The igniter 420 is fixed to the housing main body 410 via the resin molded portion 430. As a raw material for the resin molded portion 430, for example, a thermosetting resin typified by an epoxy resin is used.

[0157] The resin molding portion 430 has a first covering portion 431 covering a portion of the first end face 410a of the housing main body 410, a second covering portion 432 covering a portion of the second end face 410b of the housing main body 410, and a connecting portion 433 located within a through portion 410c provided in the partition portion 412 of the housing main body 410 and connecting the first covering portion 431 and the second covering portion 432.

[0158] The resin molded portion 430 is fixed to the housing main body 410 at the surfaces of the first covering portion 431, the second covering portion 432, and the connecting portion 433 facing the housing main body 410. More specifically, the first covering portion 431 is fixed to the inner surface of the partition wall portion 412. The second covering portion 432 includes a portion that covers the inner circumferential surface of a portion of the body portion 411 that is located on the opposite side to the cup 440 side as viewed from the partition wall portion 412, and is fixed to the inner circumferential surface and the outer surface of the partition wall portion 412. The connecting portion 433 is fixed to the surface of the partition wall portion 412 at a portion that defines the through portion 410c.

[0159] Second covering portion 432 is formed to include a first portion 432a covering the surface of recess 414 in second end face 410b of housing body 410, and a second portion 432b protruding from a portion of second end face 410b of housing body 410 where recess 414 is not provided (i.e., second end face 410b of a portion defined by trunk portion 411) toward the opposite side to cup 440. Inside second covering portion 432, terminal pin 422 of igniter 420 is arranged.

[0160] In this embodiment, resin molded portion 430 constitutes a covering portion, and second covering portion 432 constitutes a female connector portion including a recessed portion.

[0161] An inner circumferential surface of the second portion 432b of the second covering portion 432 is provided with a locking recess 432b1 capable of locking the locking projection 136 of the male connector 130. In addition, an annular projection 437 is provided on an axial end face 432d of the second covering portion 432 located on the opposite side to the cup 440 side.

[0162] Cup 440 has a combustion chamber 444 therein in which gas generating agent 450 is accommodated. Cup 440 is fixed to housing body 410 of igniter assembly 470 by crimping so that combustion chamber 444 faces ignition portion 421 of igniter 420. Scores 442a are formed on the outer surface of cup 440 as fragile portions as necessary. Cup 440 is made of a metal member such as stainless steel.

[0163] The gas generator 1D generates gas by the activation of the igniter 420. More specifically, the gas generating agent 450 accommodated in the combustion chamber 444 is ignited and burned by a flame generated by the activation of the igniter 420, generating a large amount of working gas. The generated working gas opens the cup 440 starting from the score 442a and is ejected to the outside of the housing. The ejected gas is introduced into an operating space of a pretensioner in which the gas generator 1D is incorporated, and is used for the winding operation of the seat belt.

[0164] Even when configured in this manner, effects similar to those described in the above-mentioned first embodiment can be obtained, and in a gas generator having a female connector portion made of a resin molded body used to energize the igniter, it is possible to improve sealing performance with a simple configuration.

[0165] (Additional Note) The characteristic configurations of the gas generators disclosed in the above-mentioned embodiments and their modified examples can be summarized as follows.

[0166] [Appendix 1] A housing having a combustion chamber therein in which a gas generating agent is accommodated; an igniter having an ignition unit loaded with an ignition charge for burning the gas generating agent and a terminal pin connected to the ignition unit; a male connector electrically connected to the igniter; a female connector portion into which the male connector can be inserted and configured to hold the inserted male connector; the housing has a shelf portion which separates the combustion chamber from a space outside the housing and to which the igniter is attached, and a tubular portion which extends from an outer edge of the shelf portion toward an opposite side to the combustion chamber, The shelf portion is provided with an opening, the igniter is disposed such that the ignition portion is located closer to the combustion chamber than the shelf portion in a state in which the terminal pin is inserted through the opening, the female connector portion includes a recessed portion located inside the cylindrical portion and exposed to the outside along an axial direction of the cylindrical portion, into which a portion of the male connector can be inserted; The inner circumferential surface of the cylindrical portion is covered with a resin covering portion, an inner circumferential surface of the recessed portion is defined by the covering portion, A locking projection is provided on a peripheral surface of the male connector at a portion to be inserted into the recess, a locking recess capable of locking the locking projection is provided in the covering portion at a portion defining the inner circumferential surface of the recessed portion, the male connector has an annular opposing surface that is an exposed surface of the female connector portion that is exposed to the outside and that faces at least a portion of an axial end surface positioned so as to surround the recessed portion when the male connector is inserted into the female connector portion; a seal portion made of an elastic member is interposed between the annular opposing surface and the axial end surface in the mounted state, and is compressed by being sandwiched between the annular opposing surface and the axial end surface, thereby filling a gap generated between the annular opposing surface and the axial end surface, thereby liquid-tightly sealing the internal space of the recessed portion from the outside; a ring-shaped protrusion is provided on a portion of the axial end face which contacts the seal portion in the attached state so as to surround the recessed portion.

[0167] [Appendix 2] The housing includes a top plate portion, a bottom plate portion, and a cylindrical peripheral wall portion provided with a gas outlet, The cylindrical portion is provided on the bottom plate portion so as to protrude from the bottom plate portion toward the top plate portion, 2. The gas generator described in appendix 1, wherein the covering portion has an outer covering portion that includes a portion covering the inner surface of the cylindrical portion and is secured to the inner surface of the cylindrical portion and to the outer surface of the shelf portion, and an inner covering portion that is secured to the inner surface of the shelf portion and to the ignition portion.

[0168] [Appendix 3] 3. A gas generator as described in appendix 1 or 2, wherein, when viewed along the axial direction of the female connector portion, an outer edge of the seal portion and an outer edge of the annular opposing surface are located outside the outer edge of the annular protrusion.

[0169] [Appendix 4] 3. A gas generator as described in appendix 1 or 2, wherein, when viewed along the axial direction of the female connector portion, the annular protrusion has a protruding portion that protrudes outward beyond the outer edge of the annular opposing surface.

[0170] [Appendix 5] an annular step portion is provided on the inner edge side of the annular protrusion, such that the annular protrusion includes a first annular surface located on the inner edge side of the annular protrusion, a second annular surface located on the outer edge side of the annular protrusion and closer to the annular opposing surface than the first annular surface, and a third annular surface connecting the first annular surface and the second annular surface, 5. A gas generator according to any one of claims 1 to 4, wherein an outer edge of the seal portion abuts against the third annular surface.

[0171] [Appendix 6] 4. The gas generator according to any one of claims 1 to 3, wherein the annular protrusion is constituted by a parting line formed when molding the covering portion.

[0172] (Other forms, etc.) The shape, configuration, size, number, material, and the like of each part shown in the above-mentioned embodiment of the present invention and its modified examples can be modified in various ways without departing from the spirit of the present invention.

[0173] Furthermore, the characteristic configurations shown in the above-mentioned embodiment of the present invention and its modified examples can naturally be combined with each other without departing from the spirit of the present invention.

[0174] As such, the above-mentioned embodiment and its modified examples disclosed herein are illustrative in all respects and are not restrictive. The technical scope of the present invention is defined by the claims, and includes all modifications within the meaning and scope equivalent to the description of the claims. [Explanation of symbols]

[0175] 1A, 1B, 1B1, 1C, 1D gas generator, 10 lower shell, 11 bottom plate portion, 12 cylindrical portion, 13 protruding cylindrical portion, 13a cylindrical portion, 13b shelf portion, 14 recessed portion, 15 opening portion, 20 upper shell, 21 top plate portion, 22 cylindrical portion, 24 gas outlet, 26 sealing tape, 28 gap portion, 30 holding portion, 31 inner covering portion, 32 outer covering portion, 33 connecting portion, 34, 34B, 34B1 female connector portion, 34a axial end surface, 35 concave portion, 35a inner peripheral surface, 35a1 locking recess, 35b inner bottom surface, 36 through hole, 37, 37B,37B1 annular protrusion, 37a first annular surface, 37b second annular surface, 37c third annular surface, 38 protruding portion, 39 protrusion, 40 igniter, 41 ignition portion, 42 terminal pin, 50 cup-shaped member, 51 top wall portion, 52 side wall portion, 53 extension portion, 54 tip portion, 55 transfer chamber, 56 transfer charge, 60 combustion chamber, 61 gas generating agent, 70 lower support member, 71 bottom portion, 72 abutment portion, 73 tip portion, 80 upper support member, 81 bottom portion, 82 abutment portion, 85 cushioning material, 90 filter, 100 upper die, 100a gate, 101 lower die, 102 fixed portion, 102a fixed core portion, 102b surrounding portion, 102b1 annular recess, 103 Movable core portion, 103a protrusion portion, 104 pocket portion, 130 male connector, 131 main body portion, 131a terminal blade, 131c peripheral surface, 131d recessed portion, 132 annular opposing surface, 133 cable, 134 seal portion, 136 locking protrusion, 311 gas outlet, 320A holding portion, 326d axial end surface, 324a inner peripheral surface, 324a1 locking recessed portion, 325 cylindrical portion, 327 annular protrusion, 340 igniter, 342 ignition portion, 343 terminal pin, 360 gas generating agent, 380 filter, 414 recessed portion, 310 housing main body, 320 holding portion assembly, 320B connector portion, 321 first body portion, 322 annular protrusion portion, 323a storage portion, 324 Second body portion, 326 flange portion, 330 blocking member, 341 base portion, 350 partition member, 370 coil spring, 410 housing body, 410a first end surface, 410b second end surface, 410c penetration portion, 411 body portion, 412 partition wall portion, 420 igniter, 421 ignition portion, 422 terminal pin, 430 resin molded portion, 431 first covering portion, 432 second covering portion, 432a first portion, 432b second portion, 432b1 locking recess, 432d axial end surface, 433 connection portion, 437 annular projection, 440 cup, 442a score, 444 combustion chamber, 450 gas generating agent, 470 igniter assembly, PL parting line, S1 combustion chamber, S2 filter chamber.

Claims

1. A housing having a combustion chamber therein in which a gas generating agent is accommodated; an igniter having an ignition unit loaded with an ignition charge for burning the gas generating agent and a terminal pin connected to the ignition unit; a male connector electrically connected to the igniter; a female connector portion into which the male connector can be inserted and configured to hold the inserted male connector; The housing has a shelf portion that separates the combustion chamber from a space outside the housing and to which the igniter is attached, and a cylindrical portion that extends from an outer edge of the shelf portion toward an opposite side to the combustion chamber, The shelf portion is provided with an opening, the igniter is disposed such that the ignition portion is located closer to the combustion chamber than the shelf portion when the terminal pin is inserted through the opening, the female connector portion includes a recessed portion that is located inside the cylindrical portion and exposed to the outside along an axial direction of the cylindrical portion, so that a part of the male connector can be inserted into the recessed portion; The inner circumferential surface of the cylindrical portion is covered with a resin covering portion, an inner circumferential surface of the recessed portion is defined by the covering portion, A locking projection is provided on a peripheral surface of the male connector at a portion that is inserted into the recess, a locking recess capable of locking the locking protrusion is provided in the covering portion at a portion that defines the inner circumferential surface of the recessed portion, the male connector has an annular opposing surface that is an exposed surface of the female connector portion that is exposed to the outside and that faces at least a portion of an axial end surface positioned so as to surround the recessed portion when the male connector is inserted into the female connector portion and attached to the female connector portion; a seal portion made of an elastic member is interposed between the annular opposing surface and the axial end surface in the attached state, and is compressed by being sandwiched between the annular opposing surface and the axial end surface, thereby filling a gap generated between the annular opposing surface and the axial end surface, thereby liquid-tightly sealing an internal space of the recessed portion from the outside, a ring-shaped protrusion is provided on a portion of the axial end face which contacts the seal portion in the attached state so as to surround the recessed portion.

2. The housing includes a top plate portion, a bottom plate portion, and a cylindrical peripheral wall portion provided with a gas outlet, The cylinder portion is provided on the bottom plate portion so as to protrude from the bottom plate portion toward the top plate portion, 2. The gas generator according to claim 1, wherein the covering portion has an outer covering portion that includes a portion covering the inner circumferential surface of the cylindrical portion and is secured to the inner circumferential surface of the cylindrical portion and to the outer surface of the shelf portion, and an inner covering portion that is secured to an inner surface of the shelf portion and to the ignition portion.

3. 2. The gas generator according to claim 1, wherein an outer edge of the seal portion and an outer edge of the annular opposing surface are located outside an outer edge of the annular protrusion when viewed in an axial direction of the female connector portion.

4. 2. The gas generator according to claim 1, wherein the annular projection has a protruding portion that protrudes outward beyond an outer edge of the annular opposing surface when viewed in the axial direction of the female connector portion.

5. an annular step portion is provided on an inner edge side of the annular protrusion, such that the annular protrusion includes a first annular surface located on the inner edge side of the annular protrusion, a second annular surface located on the outer edge side of the annular protrusion and located closer to the annular opposing surface than the first annular surface, and a third annular surface connecting the first annular surface and the second annular surface, 5. The gas generator according to claim 1, wherein an outer edge of said seal portion abuts against said third annular surface.

6. 4. The gas generator according to claim 1, wherein the annular projection is configured by a parting line formed when the covering portion is molded.

Images