JP7346330B2 - gas generator - Google Patents

Description

The present invention relates to a gas generator incorporated in an occupant protection device for protecting an occupant in the event of a collision of a vehicle, and more particularly to a gas generator incorporated in an airbag device installed in an automobile or the like.

2. Description of the Related Art Conventionally, from the viewpoint of protecting occupants of automobiles, airbag devices, which are occupant protection devices, have been widely used. Airbag devices are equipped with the purpose of protecting occupants from the impact that occurs during a vehicle collision. By instantly inflating and deploying the airbag in the event of a vehicle collision, the airbag acts as a cushion and protects the occupants. It is something that accepts the body.

The gas generator is built into this airbag device, and in the event of a vehicle collision, the igniter is ignited by electricity from the control unit, and the flame generated in the igniter combusts the gas generating agent to instantly generate a large amount of gas. This is a device that inflates and deploys the airbag.

Although there are various types of gas generators, a so-called disk-type gas generator is particularly suitable for use in a driver's seat side airbag device installed in a steering wheel or the like. A disk-type gas generator has a short cylindrical housing with a closed end in the axial direction, and a gas outlet is provided on the peripheral wall of the housing, and a gas generator is provided to surround an igniter located inside the housing. A gas generating agent is housed inside the housing, and a filter is housed to further surround the gas generating agent.

In this disc-type gas generator, combustion is promoted between the combustion chamber containing the gas generating agent and the igniter, so that the gas generating agent is reliably ignited by the flame generated by the igniter. Generally, an enhancer is provided as an agent. Usually, the transfer charge is stored in a transfer chamber provided inside the cup-shaped member, and the cup-shaped member is arranged such that the transfer chamber faces the ignition part of the igniter containing the ignition charge. The member is arranged to protrude into the combustion chamber.

For the cup-shaped member, an opening is provided in advance in a material with high mechanical strength such as a stainless steel alloy, and the opening is closed with a sealing tape so that the closure of the sealing tape is broken during operation. A so-called enhancer holder is constructed of a so-called enhancer holder, and a so-called enhancer cup is constructed using a member with low mechanical strength such as aluminum so that the entire surface of the part that defines the fire transfer chamber ruptures or melts when activated. There is something called.

Here, the cup-shaped member separates the transfer chamber containing the transfer charge and the combustion chamber containing the gas generating agent so that intended combustion characteristics can be obtained during operation of the gas generator. Therefore, it is necessary that the gunpowder and the gas generating agent are assembled to the housing in such a way that at least they do not mix with each other. From this point of view, conventionally, the cup-shaped member is generally attached to the housing by caulking, press-fitting, or pinching.

For example, in the gas generator disclosed in Japanese Unexamined Patent Publication No. 2014-046704 (Patent Document 1), a first extending portion is provided in the cup-shaped member, and a first extending portion is provided between the first destination member and the housing. The cup-shaped member is fixed to the housing by sandwiching and holding the first extending portion. The contact part of the first destination member is made of metal in the combustion chamber to prevent gas from leaking through the gap that occurs between the filter and the housing when the gas generator is operated. Placed as a shield. The second covering member on the top plate side is similarly arranged as a metal shielding member. In such a case, if a gas generating agent consisting of a plurality of granular molded bodies is used, there is a risk that the gas generating agent may be unintentionally crushed due to vibrations being applied to the gas generator. Therefore, in order to prevent the gas generating agent from being crushed when it is not in operation, a cushioning material is placed so that the gas generating agent in the combustion chamber comes into contact with the gas generating agent in order to elastically hold the gas generating agent inside the housing. is often placed.

However, when a cushioning material as disclosed in Patent Document 1 is used, the number of parts increases, resulting in an increase in manufacturing costs.

In order to solve this problem, for example, Japanese Patent Application Publication No. 2016-130116 (Patent Document 2) discloses a gas generator that does not use a cushioning material. The holding member can prevent gas from leaking during operation and crushing the gas generating agent when not in operation, and a protruding tube that protrudes toward the combustion chamber is provided at a predetermined portion of the housing. The cup-shaped member is fixed to the housing of the bottom plate part by press-fitting the open end of the cup-shaped member into the bottom plate part. The holding member is a molded product formed by bending a metal plate-like member, and has an overall dome-like curved plate shape that is convex toward the top plate side. This generates a force that elastically deforms the holding member toward the top plate, and the restoring force acts as a biasing force that elastically biases the gas generating agent toward the bottom plate and the center of the combustion chamber. become. Therefore, crushing of the gas generating agent during non-operation can be prevented.

Japanese Patent Application Publication No. 2014-046704 Japanese Patent Application Publication No. 2016-130116

However, when it is decided to use the pressing member as disclosed in Patent Document 2, it is necessary to apply a load evenly when pressing the pellet-shaped gas generating agent with the curved plate-shaped pressing member. Since the member is curved, initial contact with the gas generating agent is insufficient. Therefore, in order to bring the pellet-shaped gas generating agent into close contact with the pressing member, a process is required to level out the gas generating agent while applying vibrations, which lowers the yield and increases manufacturing costs. There was a problem.

Therefore, when assembling the presser member, we created unevenness on the surface of the presser member so that the gas generating agent and the presser member came into closer contact, thereby applying the load as evenly as possible and suppressing the drop in yield. Holding members with an uneven surface require relatively complex shape machining, making manufacturing complicated and increasing manufacturing costs.As a result, manufacturing costs cannot be reduced sufficiently. It invites.

Therefore, the present invention has been made to solve the above-mentioned problems, and provides a gas generating agent that can prevent the pulverization of the gas generating agent during non-operation, and that can be manufactured more cheaply and easily. The purpose is to provide equipment.

A gas generator based on the present invention includes a housing, an igniter, a filter, a lower pressing member, an upper filter supporting member, and a cup-shaped member. The housing includes a cylindrical peripheral wall portion provided with a gas outlet, and a top plate portion and a bottom plate portion that close the axial ends of the peripheral wall portion, and contains a gas generating agent. Contains a combustion chamber inside. The above-mentioned igniter includes an ignition section containing an ignition charge that ignites when activated, and is assembled to the above-mentioned bottom plate section. The filter is a cylindrical member located inside the housing and surrounding the combustion chamber in the radial direction of the housing. The lower pressing member is disposed at the end of the combustion chamber on the bottom plate side so as to cover the boundary between the filter and the bottom plate, and supports the filter and is attached to the housing. fixed relatively immovably. The cup-shaped member has a substantially cylindrical shape with an open end on the bottom plate side and includes a fire transfer chamber containing a transfer charge therein, so that the fire transfer chamber faces the ignition portion. is arranged to protrude toward the combustion chamber side. The cup-shaped member extends outward along the inner bottom surface of the bottom plate from a top wall portion and a side wall portion that define the fire transfer chamber, and an end of the side wall portion on the bottom plate side. It has an extended bottom part. The lower pressing member includes an upright portion that covers the inner circumferential surface of the filter that is located on the bottom plate side, a cylindrical portion that is arranged to cover the cup-shaped member, the upright portion, and the cylindrical portion. It is equipped with a connecting part for connecting the parts. The connecting portion is elastically deformable and includes a second contact portion that contacts the housing or the connecting portion.

In the gas generator according to the present invention, the connecting portion is fixed by being sandwiched between the second contact portion and the housing, and the connecting portion is connected from the second contact portion to the inner periphery. It is preferable that the surface has an inclined shape that is inclined toward the top plate portion as it goes outward in the radial direction of the surface.

In the gas generator according to the present invention, the lower pressing member includes a first contact portion that contacts an inner circumferential surface of the filter located on the bottom plate side, and a first contact portion that covers the cup-shaped member. It is preferable to include a cylindrical portion arranged therein, and a connecting portion connecting the first contact portion and the cylindrical portion.

In the gas generator according to the present invention, the extending bottom portion is fixed by being sandwiched between the second contact portion of the lower pressing member in the axial direction of the housing, and the connecting portion includes a tongue piece. It is preferable to have a cut-and-raised portion or a bowl-shaped protrusion.

In the gas generator according to the present invention, the lower pressing member has a cylindrical portion located near the axial end of the first contact portion and having a uniform diameter. It has an enlarged diameter cylindrical part located in a part near the axial end located on the opposite side from the end part and whose diameter increases toward the distal end, and the outer diameter of the cylindrical part is the same as the inner diameter of the filter. It is preferable that the maximum outer diameter of the expanded diameter cylinder portion is larger than the inner diameter of the filter.

The gas generator according to the present invention may further include a resin holding part that fixes the igniter to the bottom plate part. In that case, it is preferable that the holding part has a protruding part that protrudes toward the combustion chamber, and the lower pressing member extends along the axial direction of the housing and has a protrusion that protrudes toward the combustion chamber. It is preferable that the protrusion has a cylindrical part that covers the outer circumferential surface of the protrusion. In that case, it is preferable that the lower pressing member is immovably fixed relative to the housing via the holding part by press-fitting the cylindrical part into the protruding part. .

In the gas generator according to the present invention, it is preferable that the cylindrical portion of the lower pressing member surrounds an exposed surface of the holding portion excluding an outer circumferential surface of the protruding portion.

In the gas generator according to the present invention, it is preferable that an opening through which the igniter is inserted is provided in the bottom plate part, and in that case, the holding part It is preferable that the resin molded part is fixed to a part of the inner surface of the bottom plate part and a part of the outer surface of the bottom plate part so as to close the opening part.

In the gas generator according to the present invention, it is preferable that the bottom plate portion has a protruding cylindrical portion protruding toward the top plate side, and in that case, the opening It is preferable that a portion be provided at an axial end portion of the protruding tube portion located on the top plate portion side.

According to the present invention, the cup-shaped member containing the transfer charge can be easily assembled to the housing, and the lower pressing member is elastically deformed toward the top plate to hold the gas generating agent. At the same time, it is possible to prevent the gas generating agent from being crushed when the gas generating agent is not in operation, and furthermore, it can be manufactured more cheaply and easily, so that it is possible to obtain a gas generator in which manufacturing costs are reduced.

It is a schematic sectional view of gas generator 1A in Embodiment 1 of the present invention. FIG. 2 is an enlarged sectional view of a main part of the gas generator 1A shown in FIG. 1. FIG. It is a schematic sectional view of gas generator 1B in Embodiment 2 of the present invention. 4 is an enlarged sectional view II of a main part of the gas generator 1B shown in FIG. 3. FIG. FIG. 4 is a partially cutaway side view of the lower pressing member shown in FIG. 3 in an unassembled state. 4 is a schematic cross-sectional view for explaining the assembly procedure of the gas generator 1B shown in FIG. 3. FIG. 4 is a schematic cross-sectional view for explaining the assembly procedure of the gas generator 1B shown in FIG. 3. FIG. 4 is a schematic cross-sectional view for explaining the assembly procedure of the gas generator 1B shown in FIG. 3. FIG. 4 is a schematic cross-sectional view for explaining the assembly procedure of the gas generator 1B shown in FIG. 3. FIG. 4 is a schematic cross-sectional view for explaining the assembly procedure of the gas generator 1B shown in FIG. 3. FIG. It is a schematic sectional view of gas generator 1C in Embodiment 3 of the present invention. It is a schematic sectional view of gas generator 1D in Embodiment 4 of the present invention. It is a top view of the lower side presser member based on the 1st modification. It is a sectional view of the lower side holding member concerning the 1st modification. FIG. 7 is a plan view of a lower side pressing member according to a second modification. It is a sectional view of the lower side holding member concerning the 2nd modification.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In the embodiment shown below, the present invention is applied to a disk-type gas generator suitably incorporated into an airbag device mounted on a steering wheel of an automobile or the like. In the embodiments shown below, the same or common parts are denoted by the same reference numerals in the drawings, and the description thereof will not be repeated.

(Embodiment 1)
FIG. 1 is a schematic sectional view of a gas generator 1A according to Embodiment 1 of the present invention, and FIG. 2 is an enlarged sectional view of a main part of the gas generator 1A shown in FIG. First, with reference to these FIGS. 1 and 2, the configuration of the gas generator 1A in this embodiment will be described.

As shown in FIG. 1, the gas generator 1A according to the present embodiment has a short, generally cylindrical housing with both ends closed in the axial direction, and a holding part 30 as a component is provided inside the housing. , an igniter 40, a cup-shaped member 50, a transfer charge 57, a gas generating agent 61, a lower pressing member 70, an upper filter supporting member 80, a filter 90, etc. are accommodated therein. Further, inside the housing, a combustion chamber 60 is located which mainly accommodates the gas generating agent 61 among the above-mentioned components.

The short, generally cylindrical housing includes a lower shell 10 and an upper shell 20. Each of the lower shell 10 and the upper shell 20 is a press-formed product formed by pressing a rolled metal plate member, for example. As the metal plate-like members constituting the lower shell 10 and the upper shell 20, for example, metal plates made of stainless steel, iron steel, aluminum alloy, stainless alloy, etc. are used, and preferably have a pressure of 440 [MPa] or more and 780 [MPa] or more. A so-called high-strength steel plate is used that does not cause damage such as breakage even when a tensile stress of [MPa] or less is applied.

The lower shell 10 and the upper shell 20 are each formed into a substantially cylindrical shape with a bottom, and are combined and joined so that their opening surfaces face each other to form a housing. The lower shell 10 has a bottom plate part 11 and a peripheral wall part 12, and the upper shell 20 has a top plate part 21 and a peripheral wall part 22. As a result, one end and the other end in the axial direction of the housing are closed by the bottom plate part 11 and the top plate part 21, respectively. Note that electron beam welding, laser welding, friction welding, etc. can be suitably used to join the lower shell 10 and the upper shell 20.

A protruding cylindrical portion 13 that protrudes toward the top plate portion 21 is provided at the center of the bottom plate portion 11 of the lower shell 10, so that the center portion of the bottom plate portion 11 of the lower shell 10 , a recessed portion 14 is formed. The protruding tube part 13 is a part to which the igniter 40 is fixed via the above-mentioned holding part 30, and the recessed part 14 is a part that becomes a space for providing the female connector part 34 in the holding part 30. .

The protruding cylinder part 13 is formed in a substantially cylindrical shape with a bottom, and the axial end located on the top plate part 21 side has a point-symmetric shape or a point-asymmetric shape (for example, D An opening 15 is provided in the shape of a letter, barrel, oval, etc. The opening 15 is a portion through which a pair of terminal pins 42 of the igniter 40 are inserted.

The igniter 40 is for generating a flame, and includes an ignition part 41 and the pair of terminal pins 42 described above. The ignition unit 41 includes therein an ignition powder that generates a flame by igniting and burning during operation, and a resistor for igniting the ignition powder. A pair of terminal pins 42 are connected to the ignition part 41 to ignite the ignition powder.

More specifically, the ignition part 41 includes a squib cup formed in a cup shape, and a base part that closes the open end of the squib cup and holds a pair of terminal pins 42 through which the squib cup is inserted. A resistor (bridge wire) is installed so as to connect the ends of a pair of terminal pins 42 inserted into the squib cup, and a bridge wire is installed inside the squib cup so as to surround or be close to this resistor. It has a configuration loaded with gunpowder.

Here, a nichrome wire or the like is generally used as the resistor, and ZPP (zirconium/potassium perchlorate), ZWPP (zirconium/tungsten/potassium perchlorate), lead tricinate, etc. are generally used as the igniter. Note that the above-mentioned squib cup and base are generally made of metal or plastic.

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 powder starts to burn. The hot flames created by the combustion rupture the squib cup containing the igniter. The time from when 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 part 11 with the terminal pin 42 inserted into the opening 15 provided in the protruding cylinder part 13 from inside the lower shell 10 . Specifically, a holding part 30 made of a resin molded part is provided around the protruding cylinder part 13 provided on the bottom plate part 11, and the igniter 40 is held by the holding part 30. It is fixed to the bottom plate part 11 by.

The holding part 30 is formed by injection molding (more specifically, insert molding) using a mold, and is inserted into the bottom plate part 11 through the opening 15 provided in the bottom plate part 11 of the lower shell 10. It is formed by attaching an insulating fluid resin material to the bottom plate part 11 so as to extend from a part of the inner surface to a part of the outer surface and solidifying the material.

When molding the holding part 30, the igniter 40 is inserted from inside the lower shell 10 so that the terminal pin 42 is inserted into the opening 15, and in this state, the igniter 40 and the lower shell The above-described fluid resin material is poured so as to fill the space between the base plate 10 and the base plate 10 , thereby being fixed to the bottom plate portion 11 via the holding portion 30 .

As the raw material for the holding part 30 formed by injection molding, a resin material that has excellent heat resistance, durability, corrosion resistance, etc. after curing is suitably selected and used. In that case, it is not limited to thermosetting resins such as epoxy resins, but also polybutylene terephthalate resins, polyethylene terephthalate resins, polyamide resins (such as nylon 6 and nylon 66), polypropylene sulfide resins, polypropylene oxide resins, etc. It is also possible to use thermoplastic resins. When these thermoplastic resins are selected as raw materials, it is preferable that these resin materials contain glass fiber or the like as a filler in order to ensure the mechanical strength of the holding part 30 after molding. However, if sufficient mechanical strength can be ensured with the thermoplastic resin alone, there is no need to add the filler as described above.

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 shell 10. The connecting portion 33 is located within the opening 15 provided in the bottom plate portion 11 of 10 and continues to the inner covering portion 31 and the outer covering portion 32, respectively. Of these, the inner covering portion 31 corresponds to a protruding portion that protrudes toward the combustion chamber 60 side, and has a substantially cylindrical shape.

The holding part 30 is fixed to the bottom plate part 11 at the surfaces 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 portion 30 is fixed to a side surface and a lower surface of a portion of the ignition portion 41 of the igniter 40 near the lower end, and to a surface of a portion of the terminal pin 42 of the igniter 40 near the upper end. As a result, the opening 15 is completely buried by the terminal pin 42 and the holding part 30, and the sealing performance in this part is ensured, thereby ensuring the airtightness of the space inside the housing. Note that the opening 15 may be formed in an asymmetrical shape in a plan view as described above, and by embedding the opening 15 with the connecting portion 33, the opening 15 and the connecting portion 33 are connected to the holding portion 30. It also functions as a rotation prevention mechanism to prevent the rotation of the bottom plate portion 11 with respect to the bottom plate portion 11.

A female connector portion 34 is formed in a portion of the outer covering portion 32 of the holding portion 30 that faces the outside. This female connector part 34 is a part for receiving a male connector (not shown) of a harness for connecting the igniter 40 and a control unit (not shown), and is a part for receiving a male connector (not shown) of a harness for connecting the igniter 40 and a control unit (not shown). It is located in a recessed part 14 provided in. A lower end portion of the terminal pin 42 of the igniter 40 is exposed within the female connector portion 34 . A male connector is inserted into the female connector portion 34, thereby realizing electrical continuity between the core wire of the harness and the terminal pin 42.

Alternatively, the above-described 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 that is to be covered by the holding portion 30. The adhesive layer can be formed by applying an adhesive to a predetermined position of the bottom plate portion 11 in advance and curing the adhesive.

In this way, the hardened adhesive layer is located between the bottom plate part 11 and the holding part 30, so that the holding part 30 made of a resin molded part can be more firmly fixed to the bottom plate part 11. It becomes possible. Therefore, if the adhesive layer is provided in an annular manner along the circumferential direction so as to surround the opening 15 provided in the bottom plate portion 11, it becomes possible to ensure higher sealing performance in this portion.

Here, as the adhesive applied in advance to the bottom plate part 11, an adhesive containing a resin material having excellent heat resistance, durability, corrosion resistance, etc. after curing is suitably used, such as a cyanoacrylate-based adhesive. Those containing resin or silicone resin as raw materials are particularly preferably used. In addition to the resin materials mentioned above, 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, polyarylate resin, polyether ether ketone resin , polyamide-imide resin, liquid crystal polymer, styrene rubber, olefin rubber, etc. can be used as the above-mentioned adhesive.

Here, an example of a configuration is illustrated in which the igniter 40 can be fixed to the lower shell 10 by injection molding the holding part 30 made of a resin molded part. It is also possible to use other alternative means of fixation.

The cup-shaped member 50 is arranged so as to cover a portion of the lower shell 10 including the protruding cylindrical portion 13 , an inner covering portion 31 as a protruding portion of the holding portion 30 , and the ignition portion 41 of the igniter 40 . There is. The cup-shaped member 50 has a substantially cylindrical shape with a bottom and an open end on the side of the bottom plate portion 11, and includes a transfer chamber 56 in which a transfer charge 57 is accommodated. The cup-shaped member 50 protrudes into the combustion chamber 60 in which the gas generating agent 61 is housed so that the flame transfer chamber 56 provided therein faces the ignition part 41 of the igniter 40. It is arranged to be located.

As shown in FIGS. 1 and 2, the cup-shaped member 50 extends outward from a top wall portion 51 and a side wall portion 52 that define the above-mentioned fire transfer chamber 56, and from a portion of the side wall portion 52 on the open end side. It has an annular extending bottom portion 54 provided therein. In this embodiment, the cup-shaped member 50 mainly includes a cylindrical portion 53 and an extended bottom portion 54 as the above-mentioned extended bottom portion 54 . The cylindrical portion 53 is located so as to surround the portion of the bottom plate portion 11 where the protruding cylindrical portion 13 is provided, and the extended bottom portion 54 is located near the portion where the protruding cylindrical portion 13 is provided. It is located along the inner bottom surface of the bottom plate portion 11.

The cup-shaped member 50 is a so-called enhancer cup, and has no opening in either the top wall portion 51 or the side wall portion 52, and surrounds a fire transfer chamber 56 provided therein. There is. This cup-shaped member 50 ruptures or melts as the pressure rises in the fire transfer chamber 56 and the generated heat is conducted when the transfer charge 57 is ignited by the operation of the igniter 40. A material with relatively low mechanical strength is used.

Therefore, the cup-shaped member 50 may be made of metal such as aluminum or aluminum alloy, thermosetting resin such as epoxy resin, polybutylene terephthalate resin, polyethylene terephthalate resin, or polyamide resin (for example, nylon 6 or nylon). 66, etc.), polypropylene sulfide resin, polypropylene oxide resin, etc. are preferably used.

In addition to this, the cup-shaped member 50 is made of a metal member with high mechanical strength, such as iron or copper, and has an opening in its side wall portion 52, so that the cup-shaped member 50 can be It is also possible to use a holder with a sealing tape attached to close the opening (so-called enhancer holder).

In this embodiment, the cup-shaped member 50 is held by the lower pressing member 70, and its detailed assembly structure will be described later.

The transfer charge 57 filled in the transfer chamber 56 is ignited by the flame generated by the activation of the igniter 40, and is combusted to generate thermal particles. The transfer powder 57 must be capable of reliably starting combustion of the gas generating agent 61, and is generally a composition consisting of metal powder/oxidizing agent such as B/KNO3. etc. are used. The transfer powder 57 may be in powder form or formed into a predetermined shape using a binder. The transfer powder 57 formed by the binder may have various shapes, such as granules, cylinders, sheets, spheres, single-hole cylinders, multi-hole cylinders, and tablets.

A combustion chamber 60 in which a gas generating agent 61 is housed is located in a space inside the housing surrounding a portion where the cup-shaped member 50 is disposed. Specifically, the cup-shaped member 50 is disposed to protrude into a combustion chamber 60 formed inside the housing. The space and the space provided in the portion facing the outer surface of the top wall portion 51 are configured as a combustion chamber 60.

Further, a filter 90 is arranged along the inner periphery of the housing in a space surrounding the combustion chamber 60 in which the gas generating agent 61 is accommodated in the radial direction of the housing. The filter 90 has a cylindrical shape and is arranged so that its central axis substantially coincides with the axial direction of the housing.

The gas generating agent 61 is a chemical that is ignited by thermal particles generated when the igniter 40 is activated and burns to generate gas. 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 oxidizing agent, and an additive. As the fuel, for example, triazole derivatives, tetrazole derivatives, guanidine derivatives, azodicarbonamide derivatives, hydrazine derivatives, etc., or combinations thereof are used. Specifically, for example, nitroguanidine, guanidine nitrate, cyanoguanidine, 5-aminotetrazole, etc. are preferably used. The oxidizing agent may be selected from basic nitrates such as basic copper nitrate, perchlorates such as ammonium perchlorate and potassium perchlorate, alkali metals, alkaline earth metals, transition metals, and ammonia. Nitrates containing cations are used. As the nitrate, for example, sodium nitrate, potassium nitrate, etc. are preferably used. Furthermore, examples of additives include binders, slag forming agents, combustion modifiers, and the like. As the binder, organic binders such as metal salts of carboxymethylcellulose and stearates, and inorganic binders such as synthetic hydrotalcite and acid clay can be suitably used. As the slag forming agent, silicon nitride, silica, acid clay, etc. can be suitably used. Further, as the combustion modifier, metal oxides, ferrosilicon, activated carbon, graphite, etc. can be suitably used.

The shapes of the molded bodies of the gas generating agent 61 include various shapes such as granules, pellets, cylinders, etc., and discs. In addition, in the case of a cylindrical shape, a molded body having a through hole inside the molded body (for example, a single-hole cylinder shape, a multi-hole cylinder shape, etc.) is also used. These shapes are preferably selected as appropriate according to the specifications of the airbag device in which the gas generator 1A is incorporated; for example, a shape is selected in which the gas generation rate changes over time when the gas generating agent 61 is combusted. It is preferable to select the optimal shape according to the specifications. In addition to the shape of the gas generating agent 61, it is also preferable to take into account the linear combustion rate, pressure index, etc. of the gas generating agent 61, and select the size and filling amount of the molded body as appropriate.

The filter 90 is, for example, made by winding and sintering a metal wire such as stainless steel or steel, pressing a mesh material woven with metal wires by pressing, or winding a perforated metal plate. things etc. are used. Here, as the mesh material, specifically, a stockinette wire mesh, a plain weave wire mesh, an aggregate of crimp weave metal wires, etc. are used. Examples of perforated metal plates include expanded metal, which is made by making staggered cuts in a metal plate and then pushing them out to form holes to create a mesh shape; A hook metal or the like is used in which the burrs formed around the periphery of the hole are flattened by crushing them. In this case, the size and shape of the holes to be formed can be changed as necessary, and holes of different sizes and shapes may be included on the same metal plate. Note that as the metal plate, for example, a steel plate (mild steel) or a stainless steel plate can be suitably used, and a nonferrous metal plate such as aluminum, copper, titanium, nickel, or an alloy thereof can also be used.

The filter 90 functions as a cooling means that cools the gas by removing high-temperature heat from the gas when the gas generated in the combustion chamber 60 passes through the filter 90, and also removes residue contained in the gas. It also functions as a removal means for removing (slag) etc. Therefore, in order to sufficiently cool the gas and prevent the residue from being released to the outside, it is necessary to ensure that the gas generated within the combustion chamber 60 passes through the filter 90. The filter 90 is designed such that a gap 25 of a predetermined size is formed between the peripheral wall 22 of the upper shell 20 and the peripheral wall 12 of the lower shell 10, which constitute the peripheral wall of the housing. , and is spaced apart from the surrounding wall portions 12 and 22.

A plurality of gas jet ports 23 are provided in the peripheral wall portion 22 of the upper shell 20 in the portion facing the filter 90 . This gas outlet 23 is for guiding the gas that has passed through the filter 90 to the outside of the housing.

A sealing tape 24 is attached to the main surface of the peripheral wall 22 of the upper shell 20 located on the filter 90 side so as to close the gas outlet 23 . As the seal tape 24, aluminum foil or the like coated with an adhesive member on one side is used. Thereby, the airtightness of the combustion chamber 60 is ensured.

A lower pressing member 70 is disposed at the end of the combustion chamber 60 located on the bottom plate portion 11 side. The lower side holding member 70 has an annular shape as a whole, and is disposed toward 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 pressing member 70 is located between the bottom plate portion 11 and the gas generating agent 61 near the end of the combustion chamber 60 .

As shown in FIGS. 1 and 2, the lower pressing member 70 includes a cylindrical upright portion 76 that covers the inner circumferential surface of the filter 90 near the axial end located on the bottom plate portion 11 side, and a cylindrical portion 73, and a connecting portion 74 that connects the upright portion 76 and the cylindrical portion 73. In this embodiment, in the lower pressing member 70, the above-mentioned connecting portion 74 includes a leaf spring portion 75 and a second contact portion 72. The second contact portion 72 is located in contact with the inner bottom surface of the bottom plate portion 11 of the lower shell 10 or the extended bottom portion 54 of the cup-shaped member 50 . The cylindrical portion 73 extends from the second contact portion 72 toward the inside of the housing in the radial direction, and is composed of an upper portion having a reduced diameter and a lower portion having an enlarged diameter. The lower portion thereof is positioned along the protruding tube portion 13 so as to surround the side wall portion 52 of the cup-shaped member 50, and the upper portion thereof is positioned so as to cover the outer peripheral surface of the side wall portion 52 of the cup-shaped member 50. are doing.

In this embodiment, the connecting part 74 is composed of the leaf spring part 75 and the second abutting part 72, but if it has an elastically deformable structure and the second abutting part 72, , is not limited to the structure of this embodiment. For example, the connecting portion 74 connects the second contact portion 72 and a non-contact surface that exists at a distance from the bottom plate portion 11 and the extended bottom portion 54, and connects the second contact portion 72 and the non-contact surface. It suffices if it has a connecting part. In such a case, the connecting portion is elastically deformable. Such configurations include, for example, a hairpin shape, a leaf spring shape, a spring shape, and the like.

Furthermore, an insertion opening 65 through which the ignition part 41 of the igniter 40 is inserted is provided in the center of the lower pressing member 70 .

Here, the lower part of the cylindrical part 73 of the lower pressing member 70 is press-fitted into the side wall part 52 of the cup-shaped member 50. As a result, the lower pressing member 70 is immovably fixed relative to the lower shell 10 via the holding portion 30 to which the cup-shaped member 50 is press-fitted.

In this embodiment, the connecting portion 74 of the lower pressing member 70 includes a leaf spring portion 75 and a second contact portion 72. The second contact portion 72 is located in contact with the inner bottom surface of the bottom plate portion 11 or the extended bottom portion 54 of the cup-shaped member 50 . The cylindrical portion 73 extends from the second contact portion 72 toward the inside of the housing in the radial direction, and is composed of an upper portion having a reduced diameter and a lower portion having an enlarged diameter. The lower part of the cylindrical part 73 is located along the protruding cylindrical part 13 so as to surround the side wall part 52 of the cup-shaped member 50, and the upper part thereof covers the outer peripheral surface of the side wall part 52 of the cup-shaped member 50. It's located like that.

The upright portion 76 has a cylindrical plate shape, and is disposed such that its outer circumferential surface covers the inner circumferential surface of the filter 90 . The second contact portion 72 has a substantially annular shape, and at least its peripheral edge portion is in contact with the inner surface of the bottom plate portion 11 or the extended bottom portion 54 . The leaf spring part 75 has a connecting part 74 that connects the axial end of the upright part 76 on the bottom plate part 11 side and the peripheral edge of the second abutting part 72. It is located between the contact portion 72 and the contact portion 72 . Note that the axial end of the upright portion 76 on the bottom plate portion 11 side is not in contact with the bottom plate portion 11, and a space of a lower side gap portion 78 exists between the leaf spring portion 75 and the bottom plate portion 11. .

The connecting portion 74 is in contact with the gas generating agent 61. The leaf spring portion 75 constituting the connecting portion 74 is located at a distance from the bottom plate portion 11, and extends from the peripheral edge of the second contact portion 72 toward the axial end of the upright portion 76 on the bottom plate portion 11 side. It is provided so that the distance between it and the bottom plate part 11 gradually increases. As a result, the leaf spring portion 75 as a whole has a hollow truncated conical curved plate shape convex toward the bottom plate portion 11 side. Note that in this embodiment, the entire connecting portion 74 that connects the axial end portion of the upright portion 76 on the bottom plate portion 11 side and the peripheral portion of the second contact portion 72 is constituted by the leaf spring portion 75. has been done.

The leaf spring part 75 constitutes a part of the lower side pressing member 70, and as mentioned above, connects the upright part 76 and the second contact part 72, and has an inverted V-shaped shape. .

As shown in FIG. 1, the combustion chamber 60 located above the second contact portion 72 and the leaf spring portion 75 accommodates a gas generating agent 61 made of a plurality of granular molded bodies. As a result, the chemical surface of the gas generating agent 61 loaded in the combustion chamber 60 on the bottom plate part 11 side (the approximate external shape surface of the gas generating agent group formed by gathering the gas generating agents 61 consisting of a plurality of granular compacts) ) has a mountain shape along the second contact portion 72 and the leaf spring portion 75, and the height of the drug surface from the top plate portion 21 is low at the outer peripheral portion of the combustion chamber 60; The central part of the combustion chamber 60 may have a high, V-shaped shape.

The connecting portion 74 of the lower pressing member 70 is overlapped on the extended bottom portion 54 of the cup-shaped member 50, and the connecting portion 74 has an inclined portion toward the top plate side as it goes radially outward of the inner circumferential surface. The cup-shaped member 50 is fixed to the lower pressing member 70.

The lower side holding member 70 is inserted into the part of the filter 90 on the bottom plate part 11 side, and is applied to the filter 90 and the bottom plate part 11 so as to cover the boundary between the filter 90 and the bottom plate part 11. It is located. As a result, the lower pressing member 70 is located between the bottom plate portion 11 and the gas generating agent 61 near the end of the combustion chamber 60 .

The lower side pressing member 70 mainly maintains a restoring force while elastically biasing the gas generating agent 61 made of a granular molded body toward the top plate portion 21 side when not in operation. During operation, gas generated in the combustion chamber 60 enters the inside of the filter 90 through the gap between the lower end of the filter 90 and the bottom plate part 11. It functions as a shielding member to prevent leakage without passing through. That is, when the lower side pressing member 70 is activated, the gas generated in the combustion chamber 60 flows out from the gap between the lower end of the filter 90 and the bottom plate portion 11 without passing through the inside of the filter 90. It functions as a leak prevention means to prevent it from being put away.

During operation, as the pressure within the combustion chamber 60 increases due to the gas generated in the combustion chamber 60, the elastic biasing force A applied to the connecting portion 74 of the lower pressing member 70 increases. As the elastic biasing force A becomes stronger, the upright portion 76 comes into contact with the inner circumferential surface of the filter 90 , thereby allowing air to pass through the gap between the lower end of the filter 90 and the bottom plate portion 11 without passing through the inside of the filter 90 . Prevent leakage.

The lower side holding member 70 is formed, for example, by pressing a metal plate member, and is preferably made of a steel plate such as ordinary steel or special steel (for example, a cold rolled steel plate or a stainless steel plate). ) consists of members.

Therefore, the lower pressing member 70 is made of a material having sufficiently higher mechanical strength than the cup-shaped member 50, and when the lower pressing member 70 is press-fitted into the holding part 30. , there is no risk that this will buckle.

As shown in FIG. 1, by assembling the upper shell 20 to cover the lower shell 10 and joining it to the lower shell 10, as shown in FIG. A part of the force A applied to the leaf spring part 75 on the bottom plate part 11 side is transmitted to the upright part 76 via the leaf spring part 75 which is the connecting part 74 , and causes the upright part 76 to be connected to the filter 90 . This becomes a biasing force A1 that elastically biases toward the inner peripheral surface. On the other hand, as described above, the remaining part A2 of the force A applied from the bottom plate part 11 to the second contact part 72 loses its destination because the upright part 76 does not come into contact with the filter 90, and the force A2 is applied to the second contact part 72 from the bottom plate part 11. This becomes a force that elastically deforms the portion 75 toward the bottom plate portion 11 side. As a result, the leaf spring portion 75 is elastically deformed into the curved shape as described above, and its restoring force is elastically directed toward the central portion and the top plate portion 21 of the combustion chamber 60. This acts as a biasing force B2.

Therefore, the lower pressing member 70 is placed in contact with the inner peripheral surface of the filter 90 with its upright portion 76 being elastically biased with a predetermined biasing force A1, and the leaf spring portion 75 is It is placed in contact with the gas generating agent 61 while being elastically biased with a predetermined biasing force A2. Therefore, the gas generating agent 61 made of a plurality of granular compacts loaded into the combustion chamber 60 is held in a state where it is elastically biased primarily toward the bottom plate portion 11 by the lower pressing member 70. This means that the gas generating agent 61 can be prevented from being crushed during non-operation. Furthermore, as the pressure within the combustion chamber 60 increases due to gas generation during operation, the elastic biasing forces A1 and A2 increase. Therefore, the first contact portion 71 of the lower pressing member 70 and the filter 90 and the second contact portion 72 of the lower pressing member 70 and the bottom plate portion 11 are firmly fixed, so that the inside of the filter 90 can be Prevent leakage without doing so.

As described above, in this embodiment, a molded product formed by bending a metal plate member is used as the lower side pressing member 70. As a result, the lower pressing member 70 has appropriate elasticity, and the magnitude of the biasing force B2 described above depends on the shape of the lower pressing member 70 in the unassembled state and the shape of the lower pressing member 70 in the unassembled state. It is mainly determined by the relative relationship between the dimensions in the unassembled state and the dimensions of the filter 90 into which the lower pressing member 70 is inserted.

As shown in FIG. 1, an upper filter support member 80 is disposed at an end of the combustion chamber 60 located on the top plate portion 21 side. The upper filter support member 80 has a substantially disk-like shape, and has a cylindrical third contact portion 81 that abuts the inner circumferential surface of the axial end portion of the filter 90 located on the top plate portion 21 side. and a disk-shaped fourth contact portion 82 extending inward from the third contact portion 81 .

The upper filter support member 80 is placed over the filter 90 and the top plate 21 so as to cover the boundary between the filter 90 and the top plate 21. Thereby, the upper filter support member 80 is located between the top plate portion 21 and the gas generating agent 61 near the end of the combustion chamber 60 .

The upper filter support member 80 allows gas generated in the combustion chamber 60 to flow out from the gap between the upper end of the filter 90 and the top plate portion 21 without passing through the inside of the filter 90 during operation. It functions as a leak prevention means to prevent it from being put away. The upper filter support member 80, like the lower support member 70, is formed, for example, by pressing a metal plate member, and is preferably made of a steel plate (such as ordinary steel or special steel). For example, it is made of a member made of cold-rolled steel plate, stainless steel plate, etc.

(Embodiment 2)
FIG. 3 is a schematic cross-sectional view of a gas generator 1B in Embodiment 2 of the present invention. 4 is an enlarged cross-sectional view II of the main part of the gas generator 1B shown in FIG. 3, and FIG. 5 is a partially cutaway side view of the lower pressing member shown in FIG. 3 in an unassembled state. First, the configuration of the gas generator 1B in the second embodiment will be described with reference to FIGS. 3 and 4.

As shown in FIGS. 3 and 4, the gas generator 1B in this embodiment is different from the gas generator 1A in the first embodiment in the structure of the lower pressing member 70.

As shown in FIG. 4, the lower side holding member 70 is formed by bending a metal plate member, so that the lower side holding member 70 has a first contact portion that comes into contact with the inner circumferential surface of the filter 90. 71, a second contact portion 72 that contacts the bottom plate portion 11 or the extended bottom portion 54, and a connection portion 74 that connects the first contact portion 71 and the second contact portion 72.

The lower pressing member 70 includes a cylindrical first contact portion 71 that abuts the inner circumferential surface of the filter 90 near the axial end located on the bottom plate portion 11 side, a cylindrical portion 73, and the first abutment portion 71. It has a connecting part 74 that connects the contact part 71 and the cylindrical part 73.

As shown in FIG. 3, by assembling the upper shell 20 to cover the lower shell 10 and joining it to the lower shell 10, as shown in FIG. A part of the force A applied to the leaf spring part 75 on the bottom plate part 11 side is transmitted to the first contact part 71 via the leaf spring part 75, which is the connection part 74, and becomes a biasing force A1 that elastically biases the filter 90 toward the inner circumferential surface of the filter 90. On the other hand, as described above, the remaining part A2 of the force A applied from the bottom plate part 11 to the second contact part 72 loses its destination when the first contact part 71 contacts the filter 90, and the connection is interrupted. This becomes a force that elastically deforms the plate spring portion 75, which is the portion 74, toward the bottom plate portion 11 side. As a result, the leaf spring portion 75 is elastically deformed into the curved shape as described above, and its restoring force acts as a biasing force B1 that elastically biases the gas generating agent 61 toward the center side. This acts as a biasing force B2 that elastically biases the combustion chamber 60 toward the top plate portion 21 side.

Therefore, the lower pressing member 70 is arranged in contact with the inner circumferential surface of the filter 90 with its first contact portion 71 being elastically biased with a predetermined biasing force A1, and its leaf spring portion 75 is placed in contact with the gas generating agent 61 while being elastically biased with a predetermined biasing force A2. Therefore, the gas generating agent 61 made of a plurality of granular compacts loaded into the combustion chamber 60 is held in a state where it is elastically biased primarily toward the bottom plate portion 11 by the lower pressing member 70. This means that the gas generating agent 61 can be prevented from being crushed during non-operation. Furthermore, as the pressure within the combustion chamber 60 increases due to gas generation during operation, the elastic biasing forces A1 and A2 increase. Therefore, the first contact portion 71 of the lower pressing member 70 and the filter 90 and the second contact portion 72 of the lower pressing member 70 and the bottom plate portion 11 are firmly fixed, so that the inside of the filter 90 can be Prevent leakage without doing so.

As described above, in this embodiment, a molded product formed by bending a metal plate member is used as the lower side pressing member 70. As a result, the lower pressing member 70 has appropriate elasticity, and the magnitudes of the biasing forces B1 and B2 described above depend on the shape of the lower pressing member 70 in the unassembled state and the lower pressing member 70 in the unassembled state. It is mainly determined by the relative relationship between the dimensions of the member 70 in the unassembled state and the dimensions of the filter 90 into which the lower pressing member 70 is inserted.

As shown in FIG. 5, in the unassembled state, the lower pressing member 70 has a first abutting portion 71 having a cylindrical plate shape, and a second abutting portion 72 having an annular shape. The plate spring portion 75, which is the connecting portion 74, has a hollow truncated conical curved plate shape that is convex from the axial end of the first contact portion 71 toward the second contact portion 72 side. have.

Here, the second contact portion 72 is located further outside the axial end of the first contact portion 71 to which the leaf spring portion 75 is connected along the axial direction of the lower pressing member 70. The plate spring portion 75 of the portion connected to the second contact portion 72 is also located closer to the bottom plate portion 11 than the axial end portion of the first contact portion 71 .

On the other hand, the first contact part 71 has a cylindrical part 76a that is located near the axial end continuous with the leaf spring part 75 and has a uniform diameter, and a cylindrical part 76a that is located on the side opposite to the axial end. It includes an enlarged-diameter cylindrical portion 76b that is located near the end in the axial direction and whose diameter increases toward the distal end. Here, the outer diameter of the cylindrical portion 76a is the same as or slightly smaller than the inner diameter of the filter 90, and the maximum outer diameter of the expanded diameter cylindrical portion 76b is slightly larger than the inner diameter of the filter 90. It is said to be the size.

As a result, when assembling the lower pressing member 70 to the filter 90, which will be described later, the outer circumferential surface of the first abutting part 71 reliably abuts the inner circumferential surface of the filter 90, and the second abutting part 72 is pushed in by the bottom plate part 11, and the force A2 applied to the second contact part 72 is sufficiently applied to the first contact part 71 and the leaf spring part 75 to become the force A1, and the above-mentioned biasing force B1, A suitable amount of B2 can be obtained.

Therefore, by using the lower pressing member 70 having the structure in the unassembled state as shown in FIG. 5, the assembled structure of the lower pressing member 70 shown in FIGS. 3 and 4 can be realized.

As described above, in the gas generator 1B according to the present embodiment, the extended bottom portion 54 of the cup-shaped member 50 is connected to the second contact portion 72 forming the connection portion 74 of the lower side pressing member 70 and the bottom plate portion 11. The cup-shaped member 50 is fixed to the lower pressing member 70. As described above, the cup-shaped member 50 is fixed to the lower shell 10 via the inner covering part 31 as a protrusion of the holding part 30 integrated into the lower shell 10 by insert molding. As a result, the cup-shaped member 50 is fixed relatively immovably to the housing via the lower pressing member 70 and the holding part 30. Note that the second contact portion 72 does not need to be superimposed on the bottom plate portion 11 via the extended bottom portion 54, and the second contact portion 72 and the bottom plate portion 11 may directly contact each other.

Next, with reference to FIG. 3, the operation of the gas generator in this embodiment described above will be described.

When a vehicle equipped with the gas generator of this embodiment collides, the collision is detected by a collision detection means separately provided in the vehicle, and based on this, the control unit separately provided in the vehicle turns on electricity. The igniter 40 is activated. The transfer charge 57 housed in the transfer chamber 56 is ignited and burned by the flame generated by the activation of the igniter 40, generating a large amount of thermal particles. The cup-shaped member 50 ruptures or melts due to the combustion of the transfer charge 57, and the above-mentioned thermal particles flow into the combustion chamber 60.

The flowing thermal particles ignite and burn the gas generating agent 61 housed in the combustion chamber 60, generating a large amount of gas. The gas generated in the combustion chamber 60 passes through the filter 90, and at this time, the filter 90 removes heat and cools the gas, and the filter 90 removes residues contained in the gas and passes through the gap 25. flows into.

As the pressure in the internal space of the housing increases, the sealing tape 24 that was closing the gas outlet 23 provided in the upper shell 20 ruptures, and gas flows out of the housing through the gas outlet 23. It is squirted. The ejected gas is introduced into an airbag provided adjacent to the gas generator, and inflates and deploys the airbag.

6 to 10 are schematic cross-sectional views for explaining the assembly procedure of the gas generator 1B in the second embodiment. Next, with reference to FIGS. 6 to 10, a procedure for assembling the gas generator 1B in the second embodiment will be described.

When assembling the gas generator 1B, the lower shell 10 manufactured by press molding in advance and the igniter 40 manufactured in advance are set in a mold for insert molding, and insert molding is performed in this state. As a result, a holding part 30 as a resin molded part is formed on the bottom plate part 11 of the lower shell 10, and thereby the igniter 40 is fixed to the protruding tube part 13 of the lower shell 10.

Next, as shown in FIG. 6, while positioned using the jig 100, a predetermined amount of transfer charge 57 is filled into the cup-shaped member 50 manufactured by press molding in advance, and the lower side is pressed down. A portion of the lower shell 10 in the vicinity of the protruding cylindrical portion 13 to which the member 70 is fixed is inserted along the inside of the cup-shaped member 50 from the open end side of the cup-shaped member 50 . Here, the insertion operation is performed with both the cup-shaped member 50 and the lower shell 10 upside down in order to prevent the transfer powder 57 from spilling from the cup-shaped member 50. .

Next, the lower pressing member 70, which has been manufactured in advance by press molding, is inserted into the lower shell 10 in which the cup-shaped member 50 is assembled to the igniter 40. At this time, the tip of the lower pressing member 70 is bent toward the top plate.

A prefabricated filter 90 is assembled to the lower shell 10. More specifically, the filter 90 is inserted so that its inner peripheral surface contacts the outer peripheral surface of the first contact portion 71 of the lower pressing member 70 . As a result, the filter 90 is supported by the lower pressing member 70, and the filter 90 is assembled to the lower shell 10. The extended bottom portion 54 of the cup-shaped member 50 is brought into contact with the second contact portion 72 of the lower pressing member 70 .

Next, as shown in FIG. 7, a space defined by the cup-shaped member 50, the lower pressing member 70, the upper filter supporting member 80, and the filter 90 and located above the lower pressing member 70 is filled with A predetermined amount of gas generating agent 61 is filled.

Next, as shown in FIG. 8, the upper filter support member 80 is assembled to the filter 90 while being positioned using the jig 100. More specifically, the upper filter support member 80 is inserted into the inner peripheral surface of the filter 90.

Next, as shown in FIG. 9, the jig 100 is removed, and the upper shell 20 is assembled to cover the lower shell 10, and this is joined to the lower shell 10. As shown, the manufacturing of the gas generator 1B is completed. At this time, the lower pressing member 70 is pressed by the upper shell 20, and the elastic biasing force A of the lower pressing member 70 acts, increasing the drug capacity and imparting a restoring force B. The gas generating agent 61 is suppressed.

As explained above, by using the gas generator 1B according to the present embodiment, the cup-shaped member 50 is reliably fixed to the lower shell 10, and is easily assembled by a simple assembly operation. It becomes possible to fix the cup-shaped member 50 to the lower shell 10.

Here, in the gas generators 1A and 1B in this embodiment and 1C and 1D described later, even when an enhancer cup, which is a fragile member with relatively low mechanical strength, is used as the cup-shaped member 50, Since it is not necessary to press-fit this into the holding part 30 etc., it is no longer necessary to control the external dimensions of the enhancer cup as the cup-shaped member 50 more strictly than necessary, and in this respect, manufacturing costs can be significantly reduced. Become. Further, since there is no need to press fit the enhancer cup as the cup-shaped member 50 into the holding portion 30 or the like, problems such as buckling of the enhancer cup do not occur.

Furthermore, in the gas generators 1A to 1D in this embodiment, there is no need to provide a crimping flange on the lower shell 10, so there is no need for cutting or the like to form the flange. In this respect as well, manufacturing costs can be significantly reduced.

Further, by using the gas generators 1A to 1D in this embodiment, the exposed surface inside the housing of the holding part 30 made of a resin molded part is surrounded by the lower pressing member 70 as described above. can do. By adopting this configuration, it is possible to avoid exposing the holding part 30 made of the resin-formed part to flame during operation, thereby greatly reducing the generation of harmful gas components such as carbon monoxide. A suppressive effect can also be obtained.

Therefore, by using the gas generators 1A to 1D in this embodiment, not only the manufacturing cost can be reduced, but also the gas generators can have higher performance.

(Embodiment 3)
FIG. 11 is a schematic diagram of a gas generator 1C in Embodiment 3 of the present invention. With reference to FIG. 11, the configuration of the gas generator 1C in the third embodiment will be described.

As shown in FIG. 11, the gas generator 1C according to the third embodiment has an upper side retainer having a structure different from that of the upper filter support member 80 when compared with the gas generator 1B according to the second embodiment described above. The difference is that a member 80a is included.

Specifically, in the upper pressing member 80a, the cup-shaped portion 85, the fourth contact portion 82 at the upper end of the cup-shaped portion 85 and in contact with the upper shell 21, and the cup-shaped portion 85 It has a fourth abutting part 82 which is a radial end of the part that contacts the filter, and a connecting part 83 which connects the fourth abutting part 82 and the third abutting part 81. Here, the connecting portion 83 is a leaf spring portion 84 extending outward from the peripheral edge of the third contact portion 81 .

Thereby, the gas generating agent 61 is filled so as to come into contact with the bottom surface of the cup-shaped portion 85, so that the jig 100 is not required when assembling the inflator. Here, the gas generating agent 61 is filled so as to be below the upper end of the filter 90, and a part of the upper pressing member 80a is inserted from the upper end of the filter 90.

The upper side pressing member 80a of the gas generator 1C in the third embodiment has a hairpin shape formed by the side wall portion of the cup-shaped portion 85, the fourth contact portion 82, and the connection portion 83. . In this way, there is an upper gap 86 between the fourth contact portion 82 and the disk portion 11 of the cup-shaped portion 85, and by providing an elastic shape, the gas generating agent 61 can be biased and held by the upper pressing member 80a.

(Embodiment 4)
FIG. 12 is a schematic diagram of a gas generator 1D in Embodiment 4 of the present invention. With reference to FIG. 12, the configuration of gas generator 1D in the fourth embodiment will be described.

As shown in FIG. 12, the gas generator 1D according to the fourth embodiment has a different structure from the cup-shaped member 50 when compared with the gas generator 1A according to the first embodiment described above. There are differences in

Specifically, the cup-shaped member 50 does not have a cylindrical portion 53, an extended bottom portion 54, and a tip portion 55, the side wall portion 52 extends toward the axial bottom plate portion 11, and the tip portion has a flange portion. 58 and covers the inner coating portion 31. The flange portion 58 extends outward from the peripheral edge. The cup-shaped member 50 is press-fitted into the inner coating portion 31.

As a result, the cup-shaped member 50 is fixed without being sandwiched between the lower pressing member 70 and the bottom plate 11, so the space volume of the combustion chamber 60 filled with the gas generating agent 61 is increased, and a large amount of the gas generating agent 61 can be filled. Can be filled.

(First modification)
FIG. 13 is a plan view of the lower pressing member according to the first modification. Moreover, FIG. 14 is a sectional view of a plan view of the lower side pressing member according to the first modification. With reference to FIGS. 13 and 14, the configuration of the lower pressing member 70 in the first modification will be described.

As shown in FIG. 13, the lower filter support member 70 according to the first modification differs from the lower filter support member 70 according to the gas generator 1A of the first embodiment described above in the shape of the cut-and-raised portion 72a. ing. Specifically, in the first modification, 12 cut-and-raised portions 72a are provided at equal intervals along the circumferential direction of the second contact portion 72, and each of the cut-and-raised portions 72a is formed by a substantially trapezoidal tongue piece. It is configured. That is, in this first modification, the second contact portion 72 exists as a plurality of tongue-like bottom portions. As shown in FIG. 14, the connection part 74 between the first contact part 71 and the second contact part 72 is formed by an annular plate part 77 extending from the cylindrical part and a cut and raised part formed in the annular plate part 77. portion 72a and an upright portion 76 erected from the radially outer end surface of the annular plate portion 77. Note that the upright portion 76 does not need to be in contact with the first contact portion 71 with the inner circumferential surface of the filter 90, and can be selected as appropriate.

In this case, as shown in FIG. 14, by cutting and raising a part of the lower side holding member 70, the space created by cutting and raising when the upper shell 20 is press-fitted is elastically deformed, and the lower side gap 78 will fill the void. A restoring force of elastic bias acts on the gas generating agent 61 due to the reaction force of the cut and raised portion 72a. It is preferable that the size of the cut and raised portion 72a is smaller than the diameter of the gas generating agent 61, thereby preventing the gas generating agent 61 from flowing into the space of the lower side gap 78, and reducing the elasticity of the connecting portion 74. It is structured so that it does not interfere with granting.

In this first modification, 12 cut-and-raised portions 72a are provided at equal intervals along the circumferential direction of the annular plate portion 77, but any number of cut-and-raised portions 72a may be present. , and any arrangement is possible. Here, it is preferable that the cut and raised portions 72a are provided at equal intervals along the circumferential direction, but the present invention is not limited thereto.

In the first modified example, the cut and raised portion 72a is formed of a tongue piece, but the shape is not limited to this. For example, the shape may be rectangular, circular, trapezoidal, or the like.

(Second modification)
FIG. 15 is a plan view of a lower pressing member according to a second modification. Moreover, FIG. 16 is a sectional view of the lower side pressing member according to the second modification. With reference to FIGS. 15 and 16, the configuration of the lower pressing member 70 according to the second modification will be described.

As shown in FIG. 15, the lower filter support member 70 according to the second modification is different from the lower filter support member 70 according to the gas generator 1A of the first embodiment described above in the shape of the connecting portion 74. There is. Specifically, in the second modification, the connecting portion 74 has protrusions 72b, and 12 protrusions 72b are provided at equal intervals along the circumferential direction of the annular plate portion 77. Each one is shaped like a bowl. That is, in the form of the second modification, the second contact portion 72 exists as a bowl-shaped bottom portion in contact with the bottom plate portion 11. As shown in FIG. 16, the connection part 74 between the first contact part 71 and the second contact part 72 is formed by an annular plate part 77 extending from the cylindrical part and a bowl-shaped part formed in the annular plate part 77. , and an upright portion 76 erected from the radially outer end surface of the annular plate portion 77. Note that the upright portion 76 does not need to be in contact with the first contact portion 71 with the inner circumferential surface of the filter 90, and can be selected as appropriate.

In this case, as shown in FIG. 16, by providing a protrusion 72b on a part of the lower filter support member 70, the protrusion 72b is deformed and crushed when the upper shell 20 is press-fitted. This will fill the gap in the lower side gap 78. A restoring force B of elastic bias acts on the gas generating agent 61 due to the reaction force of the protrusion 72b.

In this second modification, 12 protrusions 72b are provided at equal intervals along the circumferential direction of the annular plate part 77, but any number of protrusions 72b may be present. Any arrangement is acceptable. Here, although it is preferable that the protrusions 72b are provided at equal intervals along the circumferential direction, the present invention is not limited thereto.

In the second modification, the protrusion 72b has a bowl shape, but is not limited to this shape. For example, the shape may be a polygonal column, a polygonal pyramid, a cylinder, a cone, or the like.

Even when the configurations of the above-described first and second modifications are adopted, the same effects as those described in the above-described embodiments can be obtained.

As described above, the shape, direction, number, size, formation position, etc. of the locking portions explained in the above-described embodiments may vary as long as the cup-shaped member is locked by the locking portions. That change is possible. Further, the shape of the cup-shaped member at the portion that is locked by the locking portion can be changed in various ways as long as the cup-shaped member is locked by the locking portion.

Further, in the above-described embodiment and its modified examples, by press-fitting the lower pressing member 70 into the holding part 30, it cannot be moved relative to the lower shell 10 via the holding part 30. Although the explanation has been given by exemplifying the case where the lower side holding member 70 is fixed to the lower side shell 10, by press-fitting the lower side holding member 70 into the protruding cylindrical part 13 of the lower side shell 10, it can be made immovable relative to the lower side shell 10. Alternatively, by welding a predetermined position of the lower pressing member 70 to the lower shell 10, the lower pressing member 70 may be fixed immovably relative to the lower shell 10. Further, when insert molding the holding part 30, it may be integrally molded so that it is fixed not only to the lower shell 10 but also to the lower pressing member 70. In this way, various methods can be used to fix the lower pressing member 70 to the lower shell.

In addition, in the above-described embodiment and its modification, the explanation will be given by exemplifying a case where the exposed surface inside the housing of the holding part 30 is entirely covered by the connecting part 74 of the lower side pressing member 70. I did, but it doesn't necessarily have to be configured that way.

In addition, in the above-described embodiment and its modification examples, the lower shell 10 and the upper shell 20 are constructed of press-formed products formed by press-working a metal member; however, The present invention is not necessarily limited to this, and the lower shell 10 and the upper shell 20 may be formed by a combination of pressing and other processing (forging, drawing, cutting, etc.). However, the lower shell 10 and the upper shell 20 formed only by the other processing described above may be used.

Furthermore, the shapes of the parts shown in the above-described embodiments and their modifications can of course be changed as appropriate without departing from the spirit of the present invention.

In this way, the embodiments and their modifications 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 changes within the meaning and scope equivalent to the claims.

1A, 1B, 1C, 1D gas generator, 10 lower shell, 11 bottom plate, 12 peripheral wall, 13 protruding tube, 14 recess, 15 opening, 20 upper shell, 21 top plate, 22 peripheral wall part, 23 gas outlet, 24 sealing tape, 25 gap, 30 holding part, 31 inner covering part, 32 outer covering part, 33 connecting part, 34 female connector part, 40 igniter, 41 ignition part, 42 terminal pin , 50 cup-shaped member, 51 top wall portion, 52 side wall portion, 53 cylindrical portion, 54 extended bottom portion, 55 tip portion, 56 fire transfer chamber, 57 transfer charge, 58 flange portion, 60 combustion chamber, 61 gas generating agent , 65 opening for insertion, 70 lower side pressing member, 71 first abutting part, 72 second abutting part, 72a cut-and-raised part, 72b protrusion, 73 cylindrical part, 74 connecting part, 75 plate spring part, 76 Upright part, 76a Cylindrical part, 76b Expanded diameter cylinder part, 77 Annular plate part, 78 Lower side gap part, 80 Upper side filter support member, 80a Upper side pressing member, 81 Third contact part, 82 Fourth abutment contact portion, 83 connection portion, 84 leaf spring portion, 85 cup-shaped portion, 86 upper gap portion, 90 filter, 100 jig

Claims (6)

It is constituted by a cylindrical peripheral wall portion provided with a gas ejection port, and a top plate portion and a bottom plate portion that close the axial ends of the peripheral wall portion, and includes a combustion chamber containing a gas generating agent therein. housing and
an igniter that is assembled to the bottom plate and includes an ignition section that contains an ignition charge that ignites when activated;
a cylindrical filter located inside the housing and arranged to surround the combustion chamber in the radial direction of the housing;
Disposed at an end of the combustion chamber on the bottom plate side so as to cover a boundary between the filter and the bottom plate, supports the filter, and is fixed immovably relative to the housing. a lower side holding member;
It has a substantially cylindrical shape with an open end on the bottom plate side and includes a fire transfer chamber containing a transfer charge therein, and is oriented toward the combustion chamber so that the fire transfer chamber faces the ignition part. and a protruding cup-shaped member,
The cup-shaped member extends outward along an inner bottom surface of the bottom plate from a top wall portion and a side wall portion defining the fire transfer chamber, and an end of the side wall portion on the bottom plate side. and an extended bottom part;
The lower side pressing member includes a standing portion that covers the inner circumferential surface of the filter located on the bottom plate side, a cylindrical portion that is arranged to cover the cup-shaped member, and the vertical portion and the cylindrical portion. a connecting part for connecting the parts;
The connecting portion is elastically deformable, and includes a second contact portion that contacts the housing or the extension bottom portion, and a plate spring portion, and the connecting portion is elastically deformable as it goes radially outward from the inner peripheral surface from the second contact portion. It has an inclined shape that is inclined toward the top plate side,
A gas generator having a lower gap between the leaf spring section and the bottom plate section. The gas generator according to claim 1 , wherein the extending bottom portion is fixed by being sandwiched between the second contact portion of the lower pressing member and the housing. The lower pressing member includes a first contact portion that contacts an inner circumferential surface of the filter located on the bottom plate side, a cylindrical portion that is disposed to cover the cup-shaped member, and the first contact portion. The gas generator according to claim 1 or 2, further comprising a connecting portion that connects the cylindrical portion and the cylindrical portion. The extended bottom portion is fixed by being sandwiched between the second contact portion of the lower pressing member and the housing,
The gas generator according to claim 1 or 3, wherein the connecting portion has a tongue-shaped cut-and-raised portion or a bowl-shaped protrusion. The lower pressing member has a cylindrical portion located near the axial end of the first contact portion and having a uniform diameter;
The holding member has an enlarged diameter cylindrical portion located at a portion closer to the axial end opposite to the axial end and whose diameter increases toward the distal end,
The outer diameter of the cylindrical portion is the same as or smaller than the inner diameter of the filter,
The maximum outer diameter of the expanded diameter cylinder portion is configured to be larger than the inner diameter of the filter.
The gas generator according to claim 3 . further comprising a resin holding part that fixes the igniter to the bottom plate part,
The holding portion has a protrusion that protrudes toward the combustion chamber,
The connecting portion has a cylindrical portion that extends along the axial direction of the housing and covers an outer peripheral surface of the protruding portion,
Any one of claims 1 to 5, wherein the cylindrical part is press-fitted into the protruding part, so that the lower pressing member is immovably fixed relative to the housing via the holding part. Gas generator described in Crab.

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