JP2017061185A - Gas generator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To acquire a gas generator which prevents unexpected ignition, which can make the number of components smaller than conventional counterparts and which can be produced quickly and easily.SOLUTION: A gas generator 100 is constructed by storing a holding part 30, an igniter 40, a cup-shaped member 50, a transfer charge 56, gas generating agents 61, a lower holding member 62, an upper holding part 63, a cushioning material 64 and a filter 70 and the like in a storage space provided in a housing. Also, in the storage space provided in the housing, a gas generating agent storage chamber 60 is located in which the gas generating agents 61 are mainly stored. The igniter 40 is in a state of being inserted from the inside of a lower part side shell 10 so that a terminal pin 42 is inserted into an opening 15 when molding the holding part 30. In this state, a fluid conductive resin material is fed in so as to fill a space between the igniter 40 and the lower part side shell 10, and the igniter is fixed to a bottom plate part 11 via the holding part 30.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a gas generator incorporated in an airbag device as an occupant protection device mounted on an automobile or the like.

  As represented by Patent Document 1 below, gas generators that prevent accidental ignition (unexpected ignition due to malfunction) have been known. Specifically, a gas generator in which an ignition means including a gas generating agent and an igniter assembly is housed in a metal housing, wherein the igniter assembly includes an igniter and an igniter including an igniting agent. The igniter main body having a conductive pin extending from a metal pin is fixed to a metal cylindrical fixing member through a resin, and further has a connector connecting portion for fitting a connector connected to the conductive pin. The metal cylindrical fixing member is in a state where at least a part thereof can be electrically connected to the housing and exposed on an inner surface of the connector connecting portion; The exposed portion of the cylindrical fixing member is a ground terminal, and when the connector is connected to the connector connecting portion, the ground terminal is brought into contact with the ground terminal of the connector, and the ground lead that the connector has Which wire is adapted to be grounded and the gas generator external ground circuit are known.

JP 2013-227010 A

  In the gas generator disclosed in Patent Document 1, the number of parts increases and the manufacturing process becomes complicated, so that the gas generator cannot be manufactured quickly and easily.

  SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a gas generator that can reduce the number of parts as compared with the prior art and can be manufactured quickly and easily while preventing unexpected ignition. Is.

(1) A gas generator according to the present invention includes a top plate portion and a bottom plate portion that close each end in the axial direction, and a peripheral wall portion provided with a gas ejection port, and a housing having an accommodation space inside. A gas generating agent that is disposed in the housing space and generates gas by burning, an ignition part including an ignition agent, and a terminal pin extending from the ignition part, and a conductive resin on the bottom plate part A fixed igniter for burning the gas generating agent and the terminal pin formed integrally with the conductive resin fixing the igniter using the conductive resin. A female connector part for fitting a male connector to be connected, and the entire surface of the ignition part and the surface of the terminal pin up to a position of the terminal pin in contact with the male connector, Insulate so as not to touch the conductive resin The female connector portion that is covered with resin and formed of the conductive resin serves as a ground terminal, and when the male connector is fitted to the female connector portion, the ground terminal is The grounding lead wire of the male connector is in contact with the ground terminal of the male connector, and is grounded to a ground circuit outside the gas generator.

  According to the configuration of (1) above, the number of parts can be reduced as compared with the conventional gas generator that prevents unexpected ignition (unexpected ignition due to malfunction), and can be manufactured quickly and easily. It is.

(2) In the gas generator of the above (1), it is preferable that the insulating resin and the conductive resin have the same shrinkage rate.

(3) As another aspect, in the gas generator of the above (1), the melting temperature of the insulating resin is lower than the temperature of the conductive resin, and the insulating resin and the conductive resin The interface is formed by melting the surface of the insulating resin with the conductive resin at the time of melting and then curing the surface of the molten insulating resin and the conductive resin at the time of melting. It may be.

(4) As another aspect, in the gas generator of (1) above, the portion made of the insulating resin and the portion made of the conductive resin are bonded with an adhesive having elasticity after curing. It may be.

(5) As yet another aspect, in the gas generator of (1) above, when the igniter is fixed to the bottom plate portion with the conductive resin, it is injection molded while compressing the conductive resin. It may be. In order to improve the conductivity between the conductive resin and the housing, injection molding may be performed after applying a conductive adhesive or adhesive to the housing. Alternatively, the injection molding may be performed after a conductive member is attached to the interface between the conductive resin and the housing on the outer side of the housing.

  According to the configurations of (2) to (5) above, it is possible to ensure the sealing performance between the insulating resin portion and the conductive resin portion. In particular, according to the configuration of (3) above, since the bonding is performed by curing after the interface between the insulating resin and the conductive resin is melted, it is possible to bond more firmly. Further, according to the configuration of (4) above, even if there is a difference in shrinkage rate between the insulating resin portion and the conductive resin portion, the shrinkage rate difference is absorbed and higher in that portion. It becomes possible to ensure sealing performance.

(6) In the gas generators of the above (1) to (5), the shape of the portion made of the insulating resin that covers the terminal pins is a tapered shape that expands toward the female connector portion. Is preferred.

  With configuration (6) above, it is possible to prevent the igniter from falling into the housing.

It is a schematic cross section which shows the internal structure of the gas generator which concerns on embodiment of this invention. It is a partially expanded sectional view which shows the modification of the gas generator of FIG.

  Hereinafter, with reference to FIG. 1, the internal structure of the gas generator which concerns on embodiment of this invention is demonstrated.

(Configuration of gas generator 100)
As shown in FIG. 1, the gas generator 100 in the present embodiment has a short, substantially cylindrical housing that is closed at both ends in the axial direction. In the housing space provided inside the housing, Holding part 30, igniter 40, cup-shaped member 50, transfer agent 56, gas generating agent 61, lower holding member 62, upper holding member 63, cushion material 64, seal tape 24, filter 70, etc. as internal components Is configured to be accommodated. Further, a gas generating agent storage chamber 60 in which the gas generating agent 61 among the above-described internal components is mainly stored is located in the storage space provided inside the housing.

  The short, substantially cylindrical housing includes a lower shell 10 and an upper shell 20. Each of the lower shell 10 and the upper shell 20 is made of a press-formed product formed by pressing a rolled metal plate member.

  Each of the lower shell 10 and the upper shell 20 is formed in a substantially cylindrical shape with a bottom, and a housing is configured by joining these opening surfaces so as to face each other. The lower shell 10 has a bottom plate portion 11 and a peripheral wall portion 12, and the upper shell 20 has a top plate portion 21 and a peripheral wall portion 22. As a result, the axial end of the housing is closed by the top plate portion 21 and the bottom plate portion 11. 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.

  The upper shell 20 further includes a fixing portion 25 that is erected continuously outward from the lower end of the peripheral wall portion 22. The said fixing | fixed part 25 is a site | part for fixing a housing with respect to an external member (not shown), and the gas generator 100 is supported by the said external member after installation by this.

  As shown in FIG. 1, a projecting cylindrical portion 13 that protrudes toward the top plate portion 21 side is provided at the center portion of the bottom plate portion 11 of the lower shell 10, thereby the bottom plate of the lower shell 10. A recess 14 is formed at the center of the portion 11. The projecting cylindrical portion 13 is a portion to which the igniter 40 is fixed via the holding portion 30 described above, and the recessed portion 14 is a portion that becomes a space for providing the female connector portion 34 in the holding portion 30. .

  The projecting cylindrical portion 13 is formed in a substantially cylindrical shape with a bottom, and an opening 15 having a circular shape in plan view is provided at an axial end located on the top plate portion 21 side. The opening 15 is a part through which the pair of terminal pins 42 of the igniter 40 is inserted.

  The lower shell 10 is manufactured by pressing a metal plate member rolled as described above. Specifically, the lower shell 10 is illustrated by pressing a rolled metal plate member from above and below using, for example, a pair of molds including an upper mold and a lower mold. It is manufactured by being molded into the shape as described above.

  Here, as the metal plate-like member constituting the lower shell 10, for example, a metal plate made of stainless steel, steel, aluminum alloy, stainless alloy, or the like is used, and preferably has a tensile stress of 440 MPa to 780 MPa. A so-called high-tensile steel plate that does not cause breakage or the like even when applied is preferably used. The press working may be performed by hot forging or cold forging, but is more preferably performed by cold forging from the viewpoint of improving dimensional accuracy.

  The upper shell 20 is manufactured by pressing a metal plate member rolled as described above. Specifically, the upper shell 20 is illustrated by pressing a rolled metal plate member from above and below using, for example, a pair of molds including an upper mold and a lower mold. It is manufactured by being molded into the shape as described above. Here, as a metal plate-like member constituting the upper shell 20, a metal plate made of stainless steel, steel, an aluminum alloy, a stainless alloy, or the like can be used as in the case of the lower shell 10 described above. is there.

  As shown in FIG. 1, the igniter 40 is an ignition device for generating a flame, and includes an ignition unit 41, a pair of terminal pins 42, the entire surface of the ignition unit 41, and a pair of terminal pins 42. And an insulating resin portion 43 that covers a part of the surface (a portion of the pair of terminal pins 42 protruding from the ignition portion 41 up to a position in contact with a male connector described later). The ignition unit 41 includes therein an igniting agent that generates a flame by igniting and burning during operation, and a resistor for igniting the igniting agent. The pair of terminal pins 42 are connected to the ignition unit 41 to ignite the igniting agent. The insulating resin portion 43 includes an ignition portion 41 and a pair of terminal pins 42 so that the ignition portion 41 and the pair of terminal pins 42 are not electrically connected to the lower shell 10 and the holding portion 30 made of a conductive resin. The lower shell 10 and the holding part 30 are electrically insulated.

  More specifically, the ignition unit 41 includes a squib cup formed in a cup shape, and a base that closes the open end of the squib cup and through which the pair of terminal pins 42 are inserted and held, A resistor (bridge wire) is attached so as to connect the tips of the pair of terminal pins 42 inserted in the squib cup, and a dot is placed in the squib cup so as to surround the resistor or close to the resistor. It has a configuration loaded with explosives.

  Here, nichrome wire or the like is generally used as the resistor, and ZPP (zirconium / potassium perchlorate), ZWPP (zirconium / tungsten / potassium perchlorate), lead tricinate, or the like is generally used as the igniting agent. The squib cup and the base portion described above are generally made of metal or plastic.

  As the resin used for the insulating resin portion 43, a resin material excellent in heat resistance, durability, corrosion resistance and the like after curing is suitably selected and used. In that case, it is not limited to a thermosetting resin typified by an epoxy resin or the like, but is typified by a polybutylene terephthalate resin, a polyethylene terephthalate resin, a polyamide resin (for example, nylon 6 or nylon 66), a polypropylene sulfide resin, or a polypropylene oxide resin. It is also possible to use a thermoplastic resin. When these thermoplastic resins are selected as raw materials, it is preferable to contain glass fibers or the like as fillers in these resin materials in order to ensure the mechanical strength of the holding portion 30 after molding. However, when sufficient mechanical strength can be ensured with only the thermoplastic resin, it is not necessary to add the filler as described above.

  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 agent starts burning. The high temperature flame generated by the combustion ruptures the squib cup containing the igniting agent. The time from when the current flows through the resistor until the igniter 40 is activated is generally 2 milliseconds or less when a nichrome wire is used as the resistor.

  The igniter 40 is attached to the bottom plate portion 11 in a state where the igniter 40 is inserted from the inside of the lower shell 10 so that the terminal pin 42 is inserted into the opening 15 provided in the projecting cylindrical portion 13. Specifically, a holding portion 30 made of a resin molded portion is provided around the protruding cylindrical portion 13 provided on the bottom plate portion 11, and the igniter 40 is held by the holding portion 30. Thus, the bottom plate portion 11 is fixed.

  Here, the size of the opening 15 provided in the projecting cylindrical portion 13 is configured to be smaller than the outer shape of the ignition portion 41 which is the maximum outer shape portion of the igniter 40. By configuring in this way, even if the holding part 30 is unexpectedly damaged, the igniter 40 passes through the opening 15 due to an increase in pressure inside the housing, and the outside of the housing. And the safe operation of the gas generator 100 is ensured.

  The holding part 30 is formed by injection molding (more specifically, insert molding) using a mold, and the bottom plate part 11 is passed through an opening 15 provided in the bottom plate part 11 of the lower shell 10. It is formed by adhering a fluid conductive 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 and solidifying it. At this time, injection molding may be performed while compressing.

  The igniter 40 is inserted from the inside of the lower shell 10 so that the terminal pin 42 is inserted into the opening 15 when the holding portion 30 is molded. In this state, the igniter 40 and the lower shell The fluid conductive resin material described above is poured so as to fill the space between the base plate 10 and the bottom plate portion 11 through the holding portion 30. At this time, injection molding may be performed while compressing.

  As a raw material of the holding part 30 formed by injection molding, (1) conductive resin materials such as polyacetylene, polypyrrole, polythiophene, polyaniline, or (2) synthetic rubber, polyolefin, vinyl chloride, polystyrene, ABS resin, nylon A composite conductive resin material comprising a conductive material such as carbon black mixed with an insulating resin such as ethylene vinyl acetate copolymer, polyester, acrylic, epoxy, or urethane resin is preferably selected and used. .

  The holding part 30 includes an inner covering part 31 that covers a part of the inner surface of the bottom plate part 11 of the lower shell 10, an outer covering part 32 that covers a part of the outer surface of the bottom plate part 11 of the lower shell 10, and a lower part A connecting portion 33 is provided in the opening 15 provided in the bottom plate portion 11 of the side shell 10 and is continuous with the inner covering portion 31 and the outer covering portion 32.

  The holding part 30 is fixed to the bottom plate part 11 on the surface of each of the inner covering part 31, the outer covering part 32 and the connecting part 33 on the bottom plate part 11 side. Further, the holding unit 30 is fixed to the side surface and the lower surface of the portion near the lower end of the ignition unit 41 of the igniter 40 and the surface of the portion near the upper end of the terminal pin 42 of the igniter 40. As a result, the opening 15 is completely embedded by the terminal pin 42 and the holding part 30, and the sealing property at the part is ensured, thereby ensuring the airtightness of the space inside the housing.

  The inner covering portion 31 of the holding portion 30 is provided so as to cover only the axial end portion of the protruding cylindrical portion 13 provided on the bottom plate portion 11, and thereby the inside of the housing of the protruding cylindrical portion 13. The outer peripheral surface located at is not covered by the holding portion 30 and is exposed.

  A female connector portion 34 is formed on a portion of the holding portion 30 facing the outside of the outer covering portion 32. The female connector portion 34 is a portion for receiving a male connector (not shown) of a harness for connecting the igniter 40 and a control unit (not shown), and the bottom plate portion 11 of the lower shell 10. It is located in the hollow part 14 provided in. In the female connector portion 34, a portion near the lower end of the terminal pin 42 of the igniter 40 is disposed so as to be exposed. A male connector is inserted into the female connector portion 34, thereby realizing electrical continuity between the harness core wire and the terminal pin 42. The female connector portion 34 is made of a conductive resin and serves as a ground terminal. Since the male connector is provided with a ground terminal (not shown) that contacts the female connector portion 34 as a grounding terminal, when the male connector is fitted to the female connector portion 34, A grounding lead wire (not shown) included in the mold connector is grounded to a ground circuit outside the gas generator 100.

  Moreover, it is good also as performing the injection molding mentioned above using the lower side shell 10 by which the adhesive bond layer was previously provided in the predetermined position of the surface of the baseplate part 11 of the part which will be covered with the holding | maintenance part 30. FIG. The adhesive layer can be formed by previously applying an adhesive to a predetermined position of the bottom plate portion 11 and curing it.

  In this way, since the cured adhesive layer is positioned between the bottom plate portion 11 and the holding portion 30, the holding portion 30 made of the resin molded portion can be more firmly fixed to the bottom plate portion 11. It becomes possible. Therefore, it is possible to prevent the holding portion 30 from rotating relative to the bottom plate portion 11 after injection molding. Further, 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 the portion.

  Here, as the adhesive to be applied in advance to the bottom plate portion 11, a material containing a resin material excellent in heat resistance, durability, corrosion resistance and the like after curing as a raw material is preferably used. Those containing a resin or a silicone-based resin as a raw material are particularly preferably used. In addition to the above resin materials, phenolic resins, epoxy resins, melamine resins, urea resins, polyester resins, alkyd resins, polyurethane resins, polyimide resins, polyethylene resins, polypropylene resins, Polyvinyl chloride resin, polystyrene resin, polyvinyl acetate resin, polytetrafluoroethylene resin, acrylonitrile butadiene styrene resin, acrylonitrile styrene resin, acrylic resin, polyamide resin, polyacetal resin, polycarbonate resin, Polyphenylene ether resin, polybutylene terephthalate resin, polyethylene terephthalate resin, polyolefin resin, polyphenylene sulfide resin, polysulfone resin, polyether sulfone resin, polyester Arylate resins, polyether ether ketone resin, polyamide-imide resin, liquid crystal polymer, styrene rubber, those containing olefin rubbers such as is available as an adhesive as described above.

  The position where the adhesive is applied is not particularly limited. For example, the outer surface of the bottom plate portion 11 where the protruding cylindrical portion 13 is formed (that is, covered by the outer covering portion 32 of the holding portion 30). The entire surface of the bottom plate portion 11) or only a part thereof, or the inner surface of the portion of the bottom plate portion 11 where the protruding cylindrical portion 13 is formed (that is, the portion covered by the inner covering portion 31 of the holding portion 30). Or the entire surface of the bottom plate portion 11 that is covered by the holding portion 30.

  In the igniter 40, an adhesive layer may be provided by previously applying an adhesive to a predetermined position on the surface of the insulating resin portion 43, which is a portion to be covered by the holding portion 30. If comprised in this way, it will become possible to fix the igniter 40 firmly by the holding | maintenance part 30, like the case where the adhesive bond layer is previously provided in the baseplate part 11 mentioned above, and higher sealing performance in the said part. Can be secured. In particular, if an adhesive having elasticity after curing is applied in advance, even if there is a difference in shrinkage between the insulating resin portion 43 and the holding portion 30 made of conductive resin, It is possible to absorb the difference in shrinkage rate and ensure higher sealing performance in the portion. Examples of the adhesive having elasticity after curing include the same adhesive as that previously applied to the bottom plate portion 11 described above.

  Further, in the present embodiment, the case where the holding unit 30 is configured to be integrated with the igniter 40 and the lower shell 10 when the holding unit 30 is molded is illustrated. The holding unit 30 may be integrated only with the lower shell 10 and the igniter 40 may be assembled to the molded holding unit 30 by, for example, fitting. In that case, since the holding portion 30 is fixed only to the lower shell 10, the sealing performance between the holding portion 30 and the igniter 40 cannot be ensured by this alone. If an appropriate sealing process is performed such as arranging an O-ring on the surface, sufficient sealing performance can be ensured.

  A cup-shaped member 50 is assembled to the bottom plate portion 11 so as to cover the protruding cylindrical portion 13, the holding portion 30 and the igniter 40. The cup-shaped member 50 has a substantially cylindrical shape with an open end on the bottom plate portion 11 side, and includes a heat transfer chamber 55 in which a charge transfer agent 56 is accommodated. The cup-shaped member 50 is directed toward the gas generating agent storage chamber 60 in which the gas generating agent 61 is stored so that the heat transfer chamber 55 provided therein faces the ignition part 41 of the igniter 40. Are arranged so as to protrude.

  The cup-shaped member 50 includes a top wall portion 51 and a side wall portion 52 that define the above-described transfer chamber 55, and an extending portion 53 that extends radially outward from a portion of the side wall portion 52 on the opening end side. have. The extending portion 53 is formed so as to extend along the inner surface of the bottom plate portion 11 of the lower shell 10. Specifically, the extending portion 53 has a shape that is curved so as to follow the shape of the inner bottom surface of the bottom plate portion 11 in the vicinity of the portion where the protruding cylindrical portion 13 is provided, and the diameter thereof. A distal end portion 54 extending in a flange shape is included in a portion on the outer side in the direction.

  The distal end portion 54 of the extending portion 53 is disposed between the bottom plate portion 11 and the lower holding member 62 along the axial direction of the housing, whereby the bottom plate portion 11 and the lower side are disposed along the axial direction of the housing. It is sandwiched between the holding member 62. Here, the lower holding member 62 is pressed toward the bottom plate portion 11 by the gas generating agent 61, the cushion material 64, the upper holding member 63, and the top plate portion 21 disposed above the lower holding member 62. The cup-shaped member 50 is in a state in which the distal end portion 54 of the extending portion 53 is pressed toward the bottom plate portion 11 by the lower holding member 62 and is fixed to the bottom plate portion 11.

  The portion of the cup-shaped member 50 on the opening end side of the side wall portion 52 is extrapolated to the inner covering portion 31 that is a portion located inside the housing of the holding portion 30 so as to be press-fitted and fixed to the holding portion 30. Has been. The press-fit fixing is a fixing portion for facilitating the assembly work when the cup-shaped member 50 is assembled to the housing. The cup-shaped member 50 is also fixed to the bottom plate portion by the press-fit fixing. 11 will be fixed.

  The cup-shaped member 50 does not have an opening in any of the top wall portion 51 and the side wall portion 52 and surrounds a heat transfer chamber 55 provided therein. The cup-shaped member 50 ruptures or melts as the pressure in the transfer chamber 55 rises or conduction of generated heat occurs when the transfer powder 56 is ignited by the operation of the igniter 40. A material having a relatively low mechanical strength is used.

  Therefore, as the cup-shaped member 50, a metal member such as aluminum or an aluminum alloy, a thermosetting resin typified by an epoxy resin, a polybutylene terephthalate resin, a polyethylene terephthalate resin, a polyamide resin (for example, nylon 6 or Nylon 66 etc.), and those made of a resin member such as a thermoplastic resin typified by polypropylene sulfide resin, polypropylene oxide resin, etc. are preferably used.

  In addition to the above, the cup-shaped member 50 is made of a metal member having high mechanical strength such as iron or copper, and has an opening in the side wall portion 52. It is also possible to use one having a seal tape attached so as to close the opening.

The transfer charge 56 filled in the transfer chamber 55 is ignited by the flame generated by the operation of the igniter 40 and burns to generate hot particles. The charge transfer agent 56 must be capable of reliably starting the combustion of the gas generating agent 61, and is generally composed of a metal powder / oxidizer represented by B / KNO ₃ or the like. Things are used. As the charge transfer agent 56, a powdery one, a one molded into a predetermined shape by a binder, or the like is used. Examples of the shape of the charge transfer agent 56 molded by the binder include various shapes such as a granular shape, a columnar shape, a sheet shape, a spherical shape, a single-hole cylindrical shape, a porous cylindrical shape, and a tablet shape.

  A gas generating agent storage chamber 60 in which a gas generating agent 61 is stored is placed in a space surrounding the portion where the cup-shaped member 50 is arranged in a space inside the housing composed of the lower shell 10 and the upper shell 20. Is located. Specifically, as described above, the cup-shaped member 50 is disposed so as to protrude into the gas generating agent storage chamber 60 formed inside the housing, and the outer surface of the side wall portion 52 of the cup-shaped member 50. A space provided in a portion facing the gas generating agent accommodating chamber 60 is configured.

  A filter 70 is disposed along the inner periphery of the housing in a space surrounding the gas generating agent storage chamber 60 in the radial direction of the housing. The filter 70 has a cylindrical shape, and is arranged so that the central axis thereof substantially matches the axial direction of the housing, whereby the gas generating agent storage chamber 60 in which the gas generating agent 61 is stored. Is surrounded in the radial direction.

  The gas generating agent 61 is an agent that generates gas by being ignited and burned by hot particles generated when the igniter 40 is operated. As the gas generating agent 61, it is preferable to use a non-azide-based gas generating agent, and the gas generating agent 61 is generally formed as a molded body containing a fuel, an oxidizing agent, and an additive. As the fuel, for example, a triazole derivative, a tetrazole derivative, a guanidine derivative, an azodicarbonamide derivative, a hydrazine derivative, or a combination thereof is used. Specifically, for example, nitroguanidine, guanidine nitrate, cyanoguanidine, 5-aminotetrazole and the like are preferably used. The oxidizing agent is selected from basic nitrates such as basic copper nitrate, perchlorates such as ammonium perchlorate and potassium perchlorate, or alkali metals, alkaline earth metals, transition metals, and ammonia. Nitrate containing cations is used. As the nitrate, for example, sodium nitrate, potassium nitrate and the like are preferably used. In addition, examples of the additive include a binder, a slag forming agent, and a combustion adjusting agent. As the binder, for example, an organic binder such as a metal salt of carboxymethyl cellulose and stearate, or an inorganic binder such as synthetic hydroxytalcite and acid clay can be suitably used. As the slag forming agent, silicon nitride, silica, acid clay, etc. can be suitably used. Moreover, as a combustion regulator, a metal oxide, ferrosilicon, activated carbon, graphite, etc. can be used suitably.

  The shape of the molded body of the gas generating agent 61 includes various shapes such as granular shapes, pellet shapes, granular shapes such as columnar shapes, and disk shapes. In addition, in the cylindrical shape, a porous (for example, a single-hole cylindrical shape or a porous cylindrical shape) having a through hole inside the molded body is also used. These shapes are preferably selected as appropriate according to the specifications of the airbag apparatus in which the gas generator 100 is incorporated. For example, the shape in which the gas generation rate changes with time during the combustion of the gas generating agent 61 is selected. It is preferable to select an optimal shape according to the specifications. 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 in consideration of the linear combustion rate, the pressure index, etc. of the gas generating agent 61.

  The filter 70 is, for example, one obtained by winding and sintering a metal wire such as stainless steel or steel, one obtained by pressing a net material knitted with a metal wire, or one obtained by winding a perforated metal plate. Etc. are used. Here, as the net material, specifically, a knit metal mesh, a plain weave metal mesh, an assembly of crimped metal wires, or the like is used. The perforated metal plate may be, for example, expanded metal that has been cut into a zigzag pattern on the metal plate and expanded to form a hole or processed into a mesh shape, or a hole is formed in the metal plate and In addition, a hook metal or the like obtained by flattening the burr generated at the periphery of the hole is used. In this case, the size and shape of the hole to be formed can be appropriately changed as necessary, and holes of different sizes and shapes may be included on the same metal plate. In addition, as a metal plate, a steel plate (mild steel) or a stainless steel plate can be used suitably, and nonferrous metal plates, such as aluminum, copper, titanium, nickel, or these alloys, can also be utilized.

  The filter 70 functions as a cooling means for cooling the gas by taking away the high-temperature heat of the gas when the gas generated in the gas generating agent storage chamber 60 passes through the filter 70, and in the gas. It also functions as a removing means for removing contained residues (slag) and the like. Therefore, in order to sufficiently cool the gas and prevent the residue from being discharged to the outside, it is necessary to ensure that the gas generated in the gas generating agent storage chamber 60 passes through the filter 70. It is.

  A plurality of gas jets 23 are provided in the peripheral wall portion 22 of the upper shell 20 at the portion facing the filter 70 (that is, the peripheral wall portion of the portion located on the top plate portion 21 side from the position where the fixing portion 25 is provided). Is provided. The gas outlet 23 is for leading the gas that has passed through the filter 70 to the outside of the housing. A seal tape 24 is affixed to a main surface located on the filter 70 side of the peripheral wall portion 22 of the upper shell 20 so as to close the gas ejection port 23. As this sealing tape 24, an aluminum foil or the like having an adhesive member applied on one side is used. Thereby, the airtightness of the gas generating agent accommodation chamber 60 is ensured.

  In the gas generating agent storage chamber 60, a lower holding member 62 is disposed in the vicinity of the end located on the bottom plate portion 11 side. The lower holding member 62 has an annular shape and is disposed so as to cover the boundary portion between the filter 70 and the bottom plate portion 11. The lower holding member 62 positions and holds the filter 70 by contacting the inner peripheral surface located on the bottom plate portion 11 side of the filter 70, and the tip portion 54 of the cup-shaped member 50 between the bottom plate portion 11 and the lower holding member 62. The cup-shaped member 50 is held by sandwiching.

  During operation, the lower holding member 62 flows out of the gap between the lower end of the filter 70 and the bottom plate portion 11 without passing through the inside of the filter 70 without gas generated in the gas generating agent storage chamber 60. To prevent it. The lower holding member 62 is formed by, for example, pressing a metal plate-like member, and preferably a steel plate such as ordinary steel or special steel (for example, a cold-rolled steel plate or a stainless steel plate). ).

  An upper holding member 63 is disposed at an end portion of the gas generating agent storage chamber 60 located on the top plate portion 21 side. The upper holding member 63 has a substantially disc shape, and is disposed so as to cover the boundary portion between the filter 70 and the top plate portion 21. The upper holding member 63 positions and holds the filter 70 by contacting the inner peripheral surface located on the top plate portion 21 side of the filter 70, and holds the cushion material 64 disposed therein.

  When the upper holding member 63 is in operation, the gas generated in the gas generating agent storage chamber 60 flows out from the gap between the upper end of the filter 70 and the top plate portion 21 without passing through the inside of the filter 70. To prevent it. The upper holding member 63 is formed by, for example, pressing a metal plate-like member, like the lower holding member 62, and preferably a steel plate such as ordinary steel or special steel (for example, Cold rolled steel plate, stainless steel plate, etc.).

  An annular cushion material 64 is disposed inside the upper holding member 63 so as to contact the gas generating agent 61 accommodated in the gas generating agent accommodating chamber 60. Accordingly, the cushion material 64 is positioned between the top plate portion 21 and the gas generating agent 61 in the portion on the top plate portion 21 side of the gas generating agent storage chamber 60, and the gas generating agent 61 is placed on the bottom plate portion 11. It is pressing toward the side. The cushion material 64 is provided for the purpose of preventing the gas generating agent 61 made of a molded body from being crushed by vibration or the like, and is preferably a ceramic fiber molded body, rock wool, foamed resin (for example, (Foamed silicone, foamed polypropylene, foamed polyethylene, etc.) or a member made of rubber or the like typified by chloroprene and EPDM.

  Next, the operation before and during the operation of the gas generator 100 described above will be described.

(Before operation)
In the gas generator 100 in the present embodiment, the following operations are performed before the gas generator is originally operated. That is, since the male connector is fitted to the female connector portion 34 and the ground terminal provided in the male connector and the female connector portion 34 as the ground terminal are in contact with each other, the male connector A ground lead wire (not shown) included in the connector is grounded to a ground circuit outside the gas generator 100. Therefore, static electricity is not accumulated in the metal housing forming the gas generator 100, and unexpected ignition due to malfunction caused by static electricity is not generated.

(During operation)
When a vehicle on which the gas generator 100 according to the present embodiment is mounted collides, a collision is detected by a collision detection unit provided separately in the vehicle, and based on this, a control unit provided separately in the vehicle The igniter 40 is activated by energization. The transfer charge 56 accommodated in the transfer chamber 55 is ignited and burned by the flame generated by the operation of the igniter 40 and generates a large amount of heat particles. The cup-shaped member 50 is ruptured or melted by the combustion of the charge transfer agent 56, and the above-described hot particles flow into the gas generating agent storage chamber 60.

  Due to the flowing heat particles, the gas generating agent 61 accommodated in the gas generating agent accommodating chamber 60 is ignited and burned to generate a large amount of gas. The gas generated in the gas generating agent storage chamber 60 passes through the inside of the filter 70. At this time, heat is taken away by the filter 70 and cooled, and slag contained in the gas is removed by the filter 70. It flows into the outer peripheral edge of the housing.

  As the internal pressure of the housing increases, the sealing by the sealing tape 24 that has closed the gas outlet 23 of the upper shell 20 is broken, and gas is jetted out of the housing through the gas outlet 23. The ejected gas is introduced into an airbag provided adjacent to the gas generator 100, and expands and deploys the airbag.

(Main features of the gas generator 100)
According to the present embodiment, a gas generator that prevents unexpected ignition (unexpected ignition due to malfunction) can be reduced in the number of parts as compared with the related art, and can be manufactured quickly and easily.

  Even if there is a difference in shrinkage between the insulating resin portion 43 and the holding portion 30 made of conductive resin, an adhesive having elasticity after curing is applied to the surface of the insulating resin portion 43 or the holding portion 30. If it is applied in advance to the surface, it is possible to absorb the difference in shrinkage rate and to ensure higher sealing performance at that portion.

  Further, when the igniter 40 having the insulating resin portion is fixed to the bottom plate portion 11 with the conductive resin, by performing injection molding while compressing the conductive resin, the insulating resin portion and the conductive resin portion are separated. A sealing property between them can be secured.

  As mentioned above, although embodiment of this invention was described based on drawing, it should be thought that a specific structure is not limited to these embodiment. The scope of the present invention is shown not by the above description of the embodiment but by the scope of claims for patent, and further includes meanings equivalent to the scope of claims for patent and all modifications within the scope. For example, although not shown, a so-called cylinder type housing having a long cylindrical shape may be used instead of the housing of the above embodiment.

  In addition, as shown in FIG. 2, the insulating resin portion 143 that covers the terminal pin may have a tapered portion 143 a whose diameter increases toward the female connector portion. Thereby, it can prevent that an igniter falls out in a housing. In addition, since it is substantially the same as that of the said embodiment except the site | part which attached | subjected the code | symbol, illustration and description are abbreviate | omitted.

  Moreover, the sealing property between the insulating resin portion and the conductive resin portion can be improved by appropriately selecting the materials so that the conductive resin forming the holding portion 30 and the insulating resin have the same shrinkage rate. Can be secured. For example, by selecting a conductive polyamide resin as the conductive resin and selecting an insulating polyamide resin as the insulating resin, the sealing property can be ensured. Other examples include insulating materials that serve as base materials for conductive resins such as synthetic rubber, polyolefin, vinyl chloride, polystyrene, ABS resin, nylon, ethylene vinyl acetate copolymer, polyester, acrylic, epoxy, or urethane resin. Select a composite conductive resin material obtained by blending a conductive material such as carbon black into the resin, and use it as an insulating resin as a base material for the composite conductive resin material. Synthetic rubber, polyolefin, vinyl chloride, By selecting any one of polystyrene, ABS resin, nylon, ethylene vinyl acetate copolymer, polyester, acrylic, epoxy, or urethane resin, sealing properties can be ensured.

DESCRIPTION OF SYMBOLS 10 Lower side shell 11 Bottom plate part 12 Perimeter wall part 13 Projection cylinder part 14 Depression part 15 Opening part 20 Upper side shell 21 Top plate part 22 Perimeter wall part 23 Gas ejection port 24 Seal tape 25 Fixing part 30 Holding part 31 Inner coating | coated part 32 Outer covering portion 33 Connecting portion 34 Female connector portion 40 Igniter 41 Ignition portion 42 Terminal pins 43, 143 Insulating resin portion 50 Cup-shaped member 51 Top wall portion 52 Side wall portion 53 Extension portion 54 Tip portion 55 Heat transfer chamber 56 Transfer powder 60 Gas generating agent containing chamber 61 Gas generating agent 62 Lower holding member 63 Upper holding member 64 Cushion material 70 Filter 100 Gas generator

Claims (6)

A housing that includes a top plate portion and a bottom plate portion that close each axial end portion, and a peripheral wall portion provided with a gas ejection port, and has a housing space inside;
A gas generating agent disposed in the housing space and generating gas by burning;
An igniter for combusting the gas generating agent, having an igniter containing an igniter and a terminal pin extending from the igniter, and fixed to the bottom plate part via a conductive resin;
Using the conductive resin, a female connector part for fitting a male connector connected to the terminal pin, integrally formed with the part made of the conductive resin fixing the igniter,
With
The entire surface of the ignition part and the surface of the terminal pin up to a position in contact with the male connector among the terminal pins are covered with an insulating resin so as not to touch the conductive resin,
The female connector portion formed of the conductive resin serves as a ground terminal,
When the male connector is fitted to the female connector portion, the ground terminal is brought into contact with the ground terminal of the male connector, and the ground lead wire possessed by the male connector is outside the gas generator. A gas generator characterized by being grounded with a ground circuit.   The gas generator according to claim 1, wherein the insulating resin and the conductive resin have the same shrinkage rate. The melting temperature of the insulating resin is lower than the temperature of the conductive resin,
The interface between the insulating resin and the conductive resin is obtained by melting the surface of the insulating resin with the conductive resin at the time of melting, and then the surface of the molten insulating resin and the conductivity at the time of melting. The gas generator according to claim 1, wherein the gas generator is formed by curing a resin.   The gas generator according to claim 1, wherein the portion made of the insulating resin and the portion made of the conductive resin are bonded with an adhesive having elasticity after curing.   The gas generator according to claim 1, wherein when the igniter is fixed to the bottom plate portion with the conductive resin, injection molding is performed while compressing the conductive resin. The gas generation according to any one of claims 1 to 5, wherein a shape of a portion made of the insulating resin covering the terminal pin is a tapered shape whose diameter is expanded toward the male connector. vessel.

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