JP2021138173A - Gas generator - Google Patents

Abstract

To provide a gas generator which can easily assemble a cup-shaped member for storing a transfer charge to a housing.SOLUTION: A gas generator 1A includes: a bottom plate section 11; an igniter 40; a substantially cylindrical cup-shaped member 50 which stores a transfer charge 57; a cylindrical filter 90; and a lower section side pressing member 70 which is arranged at an end on the bottom plate section 11 side of a combustion chamber 60. The lower section side pressing member 70 has an erecting section 76 for covering an inner peripheral surface of the filter 90 and a connection section 74 for connecting a cylindrical section 73 and the erecting section 76. The connection section 74 has a second abutting section 72 which contacts a housing or an extended bottom section 54 and is elastically deformable. The cup-shaped member 50 is arranged to project toward the combustion chamber 60 side and has the extended bottom section 54 extended from an end on the bottom plate section 11 side toward the outside. The housing or the extended bottom section 54 overlaps the connection section 74 and the extended bottom section 54 is sandwiched, so that the cup-shaped member 50 is fixed to the lower section side pressing member 70.SELECTED DRAWING: Figure 1

Description

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

Conventionally, from the viewpoint of protecting occupants of automobiles and the like, airbag devices, which are occupant protection devices, have become widespread. The airbag device is equipped for the purpose of protecting the occupant from the impact generated at the time of a vehicle collision. By instantly inflating and deploying the airbag at the time of a vehicle collision, the airbag acts as a cushion for the occupant. It catches the body.

The gas generator is incorporated in this airbag device, and when a vehicle collides, the igniter is ignited by energization from the control unit, and the flame generated in the igniter burns the gas generator to instantly generate a large amount of gas. , A device that inflates and deploys the airbag.

There are various types of gas generators, and there is a so-called disc type gas generator as a gas generator preferably used for a driver's side airbag device installed in a steering wheel or the like. The disc-type gas generator has a short cylindrical housing with an axial end closed, a gas outlet is provided on the peripheral wall of the housing, and the igniter located inside the housing is surrounded. A gas generator and a filter are housed inside the housing so as to further surround the gas generator.

In this disc-type gas generator, combustion is promoted between the combustion chamber containing the gas generator and the igniter so that the gas generator is surely ignited by the flame generated by the igniter. It is common to place a flame-retardant (enhancer) as an agent. Normally, the explosive is housed in a fire extinguishing room provided inside the cup-shaped member, and the fire extinguishing chamber faces the ignition part of the igniter in which the igniter is housed. The members are arranged in a protruding state in the combustion chamber.

As the cup-shaped member, an opening is provided in advance in a member having high mechanical strength such as a stainless alloy, and the opening is closed by a sealing tape so that the closing of the sealing tape is broken at the time of operation. A so-called enhancer cup that is configured so that the entire surface of the part that defines the fire transmission room bursts or melts during operation, using a so-called enhancer holder and a member with low mechanical strength such as aluminum. There is something called.

Here, the cup-shaped member divides the combustion chamber containing the explosive and the combustion chamber containing the gas generating agent so that the intended combustion characteristics can be obtained when the gas generator is operated. At least, it is necessary that these explosives and gas generators are attached to the housing so that they do not mix with each other. From this point of view, conventionally, assembling the cup-shaped member to the housing is generally performed by caulking fixing, press-fitting fixing, or sandwiching fixing.

For example, in the gas generator disclosed in Japanese Patent Application Laid-Open No. 2014-046704 (Patent Document 1), the cup-shaped member is provided with the first extending portion, and the first addressing member and the housing are separated from each other. 1 The cup-shaped member is fixed to the housing by sandwiching and holding the extended portion. The contact part of the first addressing member is made of metal in the combustion chamber to close the gap so that gas does not leak through the gap created between the filter and the housing when the gas generator is operating. It is placed as a shielding material. The second addressing member on the top plate side is also arranged as a metal shielding material in the same manner. In such a case, when a gas generator made of a plurality of granular molded bodies is used, the gas generator may be unintentionally crushed due to vibration or the like being applied to the gas generator. Therefore, in order to prevent the gas generating agent from being crushed during non-operation, a cushioning material is provided 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 the cushioning material as disclosed in Patent Document 1 is used, there is a problem that the manufacturing cost increases because the number of parts increases.

In order to solve this problem, for example, the gas generator disclosed in Japanese Patent Application Laid-Open No. 2016-130116 (Patent Document 2) discloses a gas generator that does not use a cushion material. The holding member can prevent gas leakage during operation and crushing of the gas generating agent during non-operation, and a projecting cylinder portion is provided at a predetermined portion of the housing so as to project toward the combustion chamber side. The cup-shaped member is fixed to the housing of the bottom plate portion by press-fitting the open end of the cup-shaped member into the portion. The pressing member is composed of a molded product formed by bending a metal plate-shaped member, and has a dome-shaped curved plate shape that is convex toward the top plate portion as a whole. As a result, a force that elastically deforms the pressing member toward the top plate portion is generated, and the restoring force acts as an urging force that elastically biases the gas generating agent toward the bottom plate portion side and the center side of the combustion chamber. become. Therefore, it is possible to prevent the gas generating agent from being crushed during non-operation.

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

However, when the pressing member as disclosed in Patent Document 2 is used, 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, the initial adhesion with the gas generating agent is insufficient. Therefore, in order to bring the pellet-shaped gas generating agent and the holding member into close contact with each other, it is necessary to perform a step of leveling the gas generating agent while applying vibration, and the yield is lowered accordingly, which increases the manufacturing cost. There was a problem.

Therefore, when assembling the pressing member, the surface of the pressing member is provided with irregularities so that the gas generating agent and the pressing member are in close contact with each other, so that the load is applied as evenly as possible and the decrease in yield is suppressed. A holding member having a structure with irregularities on the surface requires relatively complicated shape processing, which complicates manufacturing and increases the manufacturing cost. As a result, the problem that the reduction of the manufacturing cost cannot be sufficiently achieved. Will be invited.

Therefore, the present invention has been made to solve the above-mentioned problems, can prevent pulverization of the gas generator during non-operation, and can be cheaper and easier to produce gas generator. The purpose is to provide a vessel.

The 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 is composed of a cylindrical peripheral wall portion provided with a gas outlet, and a top plate portion and a bottom plate portion that close the axial end of the peripheral wall portion, and contains a gas generating agent. It contains a combustion chamber inside. The igniter includes an ignition portion containing an igniting agent that ignites during operation, and is assembled to the bottom plate portion. The filter is a tubular member located inside the housing and arranged so as to surround the combustion chamber in the radial direction of the housing. The lower side pressing member is arranged 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 the housing. It is relatively immovable and fixed. The cup-shaped member has a substantially tubular shape with an open end on the bottom plate portion side, and includes a firebox in which a firebox is housed, so that the firebox faces the ignition section. It is arranged so as to project toward the combustion chamber side. The cup-shaped member extends outward from the top wall portion and the side wall portion defining the fire transmission room and the end portion of the side wall portion on the bottom plate portion side along the inner bottom surface of the bottom plate portion. It has an extended bottom. The lower side pressing member includes an upright portion that covers the inner peripheral surface of the filter located on the bottom plate portion side, a cylindrical portion that is arranged so as to cover the cup-shaped member, and the upright portion and the tubular shape. It has a connection part to connect the parts. The connection portion is elastically deformable and includes a second contact portion that comes into contact with the housing or the connection portion.

In the gas generator based on the present invention, the connection portion is fixed by being sandwiched between the second contact portion and the housing, and the connection portion is formed from the second contact portion to the inner circumference. It is preferable to have an inclined shape that inclines toward the top plate portion side toward the outer side in the radial direction of the surface.

In the gas generator based on the present invention, the lower side pressing member covers the first contact portion that contacts the inner peripheral surface of the filter located on the bottom plate portion side and the cup-shaped member. It is preferable that the cylindrical portion to be arranged and the connecting portion connecting the first contact portion and the tubular portion are provided.

In the gas generator based on the present invention, the extended bottom portion is sandwiched and fixed between the second contact portion of the lower side pressing member and the housing in the axial direction, and the connecting portion is a tongue piece. It is preferable to have a raised portion or a bowl-shaped protrusion.

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

The gas generator based on the present invention may further include a resin holding portion for fixing the igniter to the bottom plate portion. In that case, it is preferable that the holding portion has a protruding portion that protrudes toward the combustion chamber side, and the lower side pressing member extends along the axial direction of the housing and is described above. It is preferable to have a tubular portion that covers the outer peripheral surface of the protruding portion. In that case, it is preferable that the cylindrical portion is press-fitted into the protruding portion so that the lower side pressing member is fixed to the housing relatively immovably via the holding portion. ..

In the gas generator based on the present invention, it is preferable that the tubular portion of the lower side pressing member surrounds the exposed surface of the holding portion excluding the outer peripheral surface of the protruding portion.

In the gas generator based on the present invention, it is preferable that an opening arranged so that the igniter can be inserted is provided in the bottom plate portion, and in that case, the holding portion is provided. It is preferably composed of a resin molded portion fixed to a part of the inner surface of the bottom plate portion and a part of the outer surface of the bottom plate portion so as to close the opening.

In the gas generator based on the present invention, it is preferable that the bottom plate portion has a protruding tubular portion projecting toward the top plate portion, and in that case, the opening It is preferable that the portion is provided at the axial end portion of the protruding tubular portion located on the top plate portion side.

According to the present invention, the cup-shaped member containing the explosive can be easily assembled to the housing, and the lower pressing member elastically deforms toward the top plate to hold the gas generating agent. On the other hand, it is possible to prevent the gas generator from being crushed when it is not in operation, and it is possible to manufacture the gas generator at a lower cost and easily, so that the gas generator can be produced at a reduced manufacturing cost.

It is the schematic sectional drawing of the gas generator 1A in Embodiment 1 of this invention. FIG. 5 is an enlarged cross-sectional view of a main part of the gas generator 1A shown in FIG. It is the schematic sectional drawing of the gas generator 1B in Embodiment 2 of this invention. FIG. 2 is an enlarged cross-sectional view II of a main part of the gas generator 1B shown in FIG. It is a partially broken side view in the non-assembled state of the lower side holding member shown in FIG. It is a schematic cross-sectional view for demonstrating the assembly procedure of the gas generator 1B shown in FIG. It is a schematic cross-sectional view for demonstrating the assembly procedure of the gas generator 1B shown in FIG. It is a schematic cross-sectional view for demonstrating the assembly procedure of the gas generator 1B shown in FIG. It is a schematic cross-sectional view for demonstrating the assembly procedure of the gas generator 1B shown in FIG. It is a schematic cross-sectional view for demonstrating the assembly procedure of the gas generator 1B shown in FIG. It is a schematic cross-sectional view of the gas generator 1C in Embodiment 3 of this invention. FIG. 5 is a schematic cross-sectional view of the gas generator 1D according to the fourth embodiment of the present invention. It is a top view of the lower side holding member which concerns on 1st modification. It is sectional drawing of the lower side holding member which concerns on 1st modification. It is a top view of the lower side holding member which concerns on 2nd modification. It is sectional drawing of the lower side holding member which concerns on 2nd modification.

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

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

As shown in FIG. 1, the gas generator 1A in the present embodiment has a short substantially cylindrical housing in which both ends in the axial direction are closed, and a holding portion 30 as a component is inside the housing. , The igniter 40, the cup-shaped member 50, the explosive agent 57, the gas generating agent 61, the lower side holding member 70, the upper side filter supporting member 80, the filter 90, and the like. Further, inside the housing, a combustion chamber 60 in which the gas generating agent 61 of the above-mentioned components is mainly housed is located.

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, for example, pressing a rolled metal plate-like member. As the metal plate-like member constituting the lower shell 10 and the upper shell 20, for example, a metal plate made of stainless steel, steel, an aluminum alloy, a stainless alloy, or the like is used, and preferably 440 [MPa] or more and 780. A so-called high-strength steel sheet that does not break or break even when a tensile stress of [MPa] or less is applied is used.

The lower shell 10 and the upper shell 20 are each formed in a substantially cylindrical shape with a bottom, and the housing is formed by combining and 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, one end and the other end of the housing in the axial direction are closed by the bottom plate portion 11 and the top plate portion 21, respectively. For joining the lower shell 10 and the upper shell 20, electron beam welding, laser welding, friction welding, or the like can be preferably used.

A protruding tubular portion 13 projecting toward the top plate portion 21 is provided at the central portion of the bottom plate portion 11 of the lower shell 10, whereby the central portion of the bottom plate portion 11 of the lower shell 10 is provided. , The recessed portion 14 is formed. The protruding tubular portion 13 is a portion where the igniter 40 is fixed via the holding portion 30 described above, and the recessed portion 14 is a portion serving as a space for providing the female connector portion 34 in the holding portion 30. ..

The projecting tubular portion 13 is formed in a substantially cylindrical shape with a bottom, and the axial end portion located on the top plate portion 21 side thereof has a point-symmetrical shape or a non-point-symmetrical shape (for example, D) in a plan view. An opening 15 (shaped, barrel-shaped, oval-shaped, etc.) is provided. 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 unit 41 and the pair of terminal pins 42 described above. The ignition unit 41 includes an igniting agent that ignites and burns during operation to generate a flame, and a resistor for igniting the igniting agent. The pair of terminal pins 42 are connected to the ignition unit 41 to ignite the ignition charge.

More specifically, the ignition portion 41 includes a squib cup formed in a cup shape and a base portion for closing the open end of the squib cup and inserting and holding a pair of terminal pins 42. A resistor (bridge wire) is attached so as to connect the tips of a pair of terminal pins 42 inserted in the squib cup, and a point in the squib cup so as to surround or approach the resistor. It has a configuration loaded with gunpowder.

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

When a collision is detected, a predetermined amount of current flows through the resistor through the terminal pin 42. When a predetermined amount of electric current flows through the resistor, Joule heat is generated in the resistor and the igniter starts combustion. The hot flame generated by the combustion explodes the squib cup containing the igniter. The time from when a current flows through the resistor until the igniter 40 operates is generally 2 milliseconds or less when a nichrome wire is used for the resistor.

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

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

The igniter 40 is in a state of being 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 formed. In this state, the igniter 40 and the lower shell are inserted. By pouring the above-mentioned fluid resin material so as to fill the space between the 10 and 10, the fluid resin material is fixed to the bottom plate portion 11 via the holding portion 30.

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

The holding portion 30 includes an inner covering portion 31 that covers a part of the inner surface of the bottom plate portion 11 of the lower shell 10, an outer covering portion 32 that covers a part of the outer surface of the bottom plate portion 11 of the lower shell 10, and a lower shell. It is located in the opening 15 provided in the bottom plate portion 11 of 10, and has a connecting portion 33 which is continuous with the inner covering portion 31 and the outer covering portion 32, respectively. Of these, the inner covering portion 31 corresponds to a protruding portion protruding toward the combustion chamber 60 side, and has a substantially columnar shape.

The holding portion 30 is fixed to the bottom plate portion 11 on the surface of each of the inner covering portion 31, the outer covering portion 32, and the connecting portion 33 on the bottom plate portion 11 side. Further, the holding portion 30 is fixed to the side surface and the lower surface of the portion near the lower end of the ignition portion 41 of the igniter 40 and the surface of the portion near the upper end of the terminal pin 42 of the igniter 40, respectively. As a result, the opening 15 is completely embedded by the terminal pin 42 and the holding portion 30, and the sealing property in the portion is ensured, so that the airtightness of the space inside the housing is ensured. The opening 15 may be formed in a non-point symmetrical shape in a plan view as described above, and by embedding the opening 15 in the connecting portion 33, the opening 15 and the connecting portion 33 can be formed by the holding portion 30. Also functions as a detent mechanism to prevent the bottom plate portion 11 from rotating.

A female connector portion 34 is formed in 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 is a bottom plate portion 11 of the lower shell 10. It is located in the recessed portion 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 exposed and arranged. A male connector is inserted into the female connector portion 34, whereby electrical continuity between the core wire of the harness and the terminal pin 42 is realized.

Further, the injection molding described above may be performed using the lower shell 10 in which the adhesive layer is previously provided at a predetermined position on the surface of the bottom plate portion 11 of the portion 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 layer.

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

Here, as the adhesive to be applied to the bottom plate portion 11 in advance, an adhesive containing a resin material having excellent heat resistance, durability, corrosion resistance and the like as a raw material after curing is preferably used, for example, a cyanoacrylate-based adhesive. Those containing a resin or a silicone-based resin as a raw material are particularly preferably used. In addition to the above-mentioned resin materials, phenolic resin, epoxy resin, melamine resin, urea resin, polyester resin, alkyd resin, polyurethane resin, polyimide resin, polyethylene resin, polypropylene resin, etc. 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-based resin, polybutylene terephthalate-based resin, polyethylene terephthalate-based resin, polyolefin-based resin, polyphenylene sulfide-based resin, polysulfone-based resin, polyether sulfone-based resin, polyarylate-based resin, polyether ether ketone-based resin , Polyamidoimide-based resins, liquid crystal polymers, styrene-based rubbers, olefin-based rubbers, and the like can be used as the above-mentioned adhesives.

Here, a configuration example in which the igniter 40 can be fixed to the lower shell 10 by injection molding the holding portion 30 made of a resin molded portion has been illustrated, but the igniter 40 to the lower shell 10 has been illustrated. It is also possible to use other alternatives to fix the.

The cup-shaped member 50 is arranged so as to cover a portion of the lower shell 10 including the protruding tubular portion 13, an inner covering portion 31 as a protruding portion of the holding portion 30, and an ignition portion 41 of the igniter 40. There is. The cup-shaped member 50 has a substantially cylindrical shape with a bottom having an open end on the bottom plate portion 11 side, and includes a fire transmission chamber 56 in which the explosive agent 57 is housed. The cup-shaped member 50 projects toward the inside of the combustion chamber 60 containing the gas generating agent 61 so that the fire transmission chamber 56 provided inside thereof faces the ignition portion 41 of the igniter 40. Arranged to be located.

As shown in FIGS. 1 and 2, the cup-shaped member 50 extends outward from the top wall portion 51 and the side wall portion 52 that define the above-mentioned fire transmission room 56, and the portion of the side wall portion 52 on the open end side. It has an annular extending bottom 54 provided. In the present 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 tubular portion 53 is located so as to surround the portion of the bottom plate portion 11 where the protruding tubular portion 13 is provided, and the extended bottom portion 54 is in the vicinity of the portion where the protruding tubular 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, has no opening in either the top wall portion 51 or the side wall portion 52, and surrounds the fire transmission room 56 provided inside the cup-shaped member 50. There is. The cup-shaped member 50 bursts or melts when the ignition charge 57 is ignited by the operation of the igniter 40 as the pressure rises in the fire transmission room 56 and the generated heat is conducted. Those with relatively low mechanical strength are used.

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

In addition to such a cup-shaped member 50, 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 thereof. It is also possible to use a material to which a sealing tape is attached so as to close the opening (so-called enhancer holder).

Here, in the present embodiment, the cup-shaped member 50 is held by the lower side pressing member 70, and the detailed assembly structure thereof will be described later.

The explosive charge 57 filled in the fire transmission room 56 is ignited by a flame generated by the operation of the igniter 40, and burns to generate heat particles. The explosive agent 57 needs to be capable of reliably starting combustion of the gas generating agent 61, and is generally a composition composed of a metal powder / oxidizing agent typified by B / KNO3 or the like. Etc. are used. As the explosive agent 57, a powdery one, one molded into a predetermined shape by a binder, or the like is used. The shape of the explosive agent 57 formed by the binder includes 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.

In the space inside the housing, the combustion chamber 60 in which the gas generating agent 61 is housed is located in the space surrounding the portion where the cup-shaped member 50 is arranged. Specifically, the cup-shaped member 50 is arranged so as to project into the combustion chamber 60 formed inside the housing, and is provided on a portion of the cup-shaped member 50 facing the outer surface of the side wall portion 52. The space and the space provided in the portion of the top wall portion 51 facing the outer surface are configured as the combustion chamber 60.

Further, a filter 90 is arranged along the inner circumference of the housing in a space surrounding the combustion chamber 60 in which the gas generating agent 61 is housed 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 an agent that generates gas by being ignited by heat particles generated by the operation of the igniter 40 and burning. As the gas generating agent 61, it is preferable to use a non-azide gas generating agent, and generally, the gas generating agent 61 is 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, for example, basic nitrates such as basic copper nitrate, perchlorates such as ammonium perchlorate and potassium perchlorate, alkali metals, alkaline earth metals, transition metals, and ammonia. Nitrate containing cations and the like are used. As the nitrate, for example, sodium nitrate, potassium nitrate and the like are preferably used. Further, examples of the additive include a binder, a slag forming agent, a combustion adjusting agent and the like. As the binder, for example, an organic binder such as a metal salt of carboxymethyl cellulose or stearate, or an inorganic binder such as synthetic hydrotalcite or acidic clay can be preferably used. As the slag forming agent, silicon nitride, silica, acidic white clay and the like can be preferably used. Further, as the combustion modifier, metal oxide, ferrosilicon, activated carbon, graphite and the like can be preferably used.

The shape of the molded body of the gas generating agent 61 includes various shapes such as granular ones such as granules, pellets, and cylinders, and discs. Further, in the columnar shape, a perforated molded body having a through hole inside the molded body (for example, a single-hole tubular shape, a perforated tubular 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 in which the gas generation rate changes with time during combustion of the gas generator 61 is selected. It is preferable to select the optimum 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 product in consideration of the linear combustion rate, pressure index, and the like of the gas generating agent 61.

The filter 90 is, for example, a metal wire rod such as stainless steel or steel wound and sintered, a net material woven with a metal wire rod pressed and compacted, or a perforated metal plate wound around. Things etc. are used. Here, as the net material, specifically, a knitted wire mesh, a plain weave wire mesh, an aggregate of crimp-woven metal wire rods, or the like is used. Further, as a perforated metal plate, for example, an expanded metal in which a staggered cut is made in the metal plate and the metal plate is expanded to form a hole and processed into a mesh shape, or an expanded metal in which a hole is made in the metal plate and at that time. Hook metal or the like that flattens the burrs generated on the periphery of the holes by crushing them is used. In this case, the size and shape of the holes to be formed can be appropriately changed as needed, and holes of different sizes and shapes may be included on the same metal plate. As the metal plate, for example, a steel plate (mild steel) or a stainless steel plate can be preferably used, and a non-ferrous metal plate such as aluminum, copper, titanium, nickel or an alloy thereof can also be used.

The filter 90 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 combustion chamber 60 passes through the filter 90, and the residue contained in the gas. It also functions as a removing means for removing (slag) and the like. 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 in the combustion chamber 60 passes through the filter 90. In the filter 90, a gap portion 25 having a predetermined size is formed between the peripheral wall portion 22 of the upper shell 20 and the peripheral wall portion 12 of the lower shell 10 constituting the peripheral wall portion of the housing. It is arranged apart from the peripheral wall portions 12 and 22.

A plurality of gas outlets 23 are provided on the peripheral wall portion 22 of the upper shell 20 of the portion facing the filter 90. The gas outlet 23 is for leading 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 portion 22 of the upper shell 20 on the filter 90 side so as to close the gas outlet 23. As the sealing tape 24, an aluminum foil or the like having an adhesive member coated on one side is used. As a result, the airtightness of the combustion chamber 60 is ensured.

A lower side pressing member 70 is arranged at an end portion of the combustion chamber 60 located on the bottom plate portion 11 side. The lower side pressing member 70 has an annular shape as a whole, and is arranged so as to cover the boundary portion between the filter 90 and the bottom plate portion 11 so as to cover the filter 90 and the bottom plate portion 11. .. As a result, the lower side pressing member 70 is located between the bottom plate portion 11 and the gas generating agent 61 in the vicinity of the end portion of the combustion chamber 60.

As shown in FIGS. 1 and 2, the lower side pressing member 70 includes a cylindrical upright portion 76 that covers an inner peripheral surface near the axial end portion located on the bottom plate portion 11 side of the filter 90, and a cylindrical portion. It has a connecting portion 74 that connects the vertical portion 76, the vertical portion 76, and the cylindrical portion 73. In the present embodiment, in the lower side pressing member 70, the connection portion 74 described above is composed of 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 tubular portion 73 extends from the second contact portion 72 toward the inside in the radial direction of the housing, and is composed of a reduced diameter upper portion and an expanded diameter lower portion. The lower part of the cup-shaped member 50 is located along the protruding tubular 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. doing.

In the present embodiment, the connecting portion 74 is composed of the leaf spring portion 75 and the second contact portion 72, but if it is provided with an elastically deformable configuration and the second contact portion 72. , The structure is not limited to that of the present embodiment. For example, the connecting portion 74 connects the second contact portion 72, the non-contact surface existing at a distance from the bottom plate portion 11 and the extended bottom portion 54, and the second contact portion 72 and the non-contact surface. It suffices to have a connecting portion. In such a case, the connecting portion can be elastically deformed. Such a configuration includes, for example, a hairpin shape, a leaf spring shape, a spring shape, and the like.

Further, in the central portion of the lower side pressing member 70, an insertion opening 65 in which the ignition portion 41 of the igniter 40 is inserted and arranged is provided.

Here, the lower portion of the cylindrical portion 73 of the lower side pressing member 70 is press-fitted into the side wall portion 52 of the cup-shaped member 50. As a result, the lower side pressing member 70 is fixed so as to be relatively immovable with respect to the lower side shell 10 via the holding portion 30 in which the cup-shaped member 50 is press-fitted and fixed.

In the present embodiment, the connecting portion 74 of the lower side pressing member 70 is composed of 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 tubular portion 73 extends from the second contact portion 72 toward the inside in the radial direction of the housing, and is composed of a reduced diameter upper portion and an expanded diameter lower portion. The lower portion of the tubular portion 73 is located along the protruding tubular portion 13 so as to surround the side wall portion 52 of the cup-shaped member 50, and the upper portion thereof covers the outer peripheral surface of the side wall portion 52 of the cup-shaped member 50. It is located like.

The upright portion 76 has a tubular shape, and is arranged so that its outer peripheral surface covers the inner peripheral surface of the filter 90. The second contact portion 72 has a substantially annular shape, and at least the peripheral portion thereof is in contact with the inner surface of the bottom plate portion 11 or the extended bottom portion 54. The leaf spring portion 75 has a connecting portion 74 that connects the axial end portion of the standing portion 76 on the bottom plate portion 11 side and the peripheral edge portion of the second contact portion 72, and the standing portion 76 and the second It is located between the contact portion 72 and the contact portion 72. The axial end of the standing portion 76 on the bottom plate portion 11 side is not in contact with the bottom plate portion 11, and there is a space of the lower gap portion 78 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 as it goes from the peripheral edge portion of the second contact portion 72 toward the axial end portion of the standing portion 76 on the bottom plate portion 11 side. It is provided so that the distance from the bottom plate portion 11 gradually increases. As a result, the leaf spring portion 75 has a hollow cone-shaped curved plate shape that is convex toward the bottom plate portion 11 side as a whole. In the present embodiment, the entire connecting portion 74 connecting the axial end portion of the standing portion 76 on the bottom plate portion 11 side and the peripheral edge portion of the second contact portion 72 is composed of the leaf spring portion 75. Has been done.

The leaf spring portion 75 forms a part of the lower side pressing member 70, and as described above, the standing portion 76 and the second contact portion 72 are connected to form an inverted C shape. ..

As shown in FIG. 1, the combustion chamber 60 existing above the second contact portion 72 and the leaf spring portion 75 contains a gas generating agent 61 composed of a plurality of granular molded bodies. As a result, the chemical surface on the bottom plate portion 11 side of the gas generating agent 61 loaded in the combustion chamber 60 (approximate outer surface of the gas generating agent group formed by collecting the gas generating agent 61 composed of a plurality of granular molded bodies). ) Has a mountain shape along the second contact portion 72 and the leaf spring portion 75, and the height of the chemical surface from the top plate portion 21 is low in the outer peripheral portion of the combustion chamber 60. It may have a C-shaped shape that is high in the central portion of the combustion chamber 60.

The connecting portion 74 of the lower side pressing member 70 is overlapped on the extended bottom portion 54 of the cup-shaped member 50, and the connecting portion 74 is an inclined portion toward the top plate portion toward the radial outer side of the inner peripheral surface. The cup-shaped member 50 is fixed to the lower side pressing member 70.

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

The lower side pressing member 70 mainly holds the restoring force while elastically urging the gas generating agent 61 made of a granular molded body toward the top plate portion 21 side when it is not operated, so that the gas generating agent 61 It functions as a crushing prevention member for preventing crushing, and at the time of operation, the 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 portion 11. It functions as a shielding member to prevent outflow without passing through. That is, when the lower side pressing member 70 is operated, 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 an outflow prevention means to prevent it from being stowed away.

During operation, the gas generated in the combustion chamber 60 increases the pressure in the combustion chamber 60, and the elastic urging force A applied to the connection portion 74 of the lower side pressing member 70 becomes stronger. As the elastic urging force A becomes stronger, the erecting portion 76 abuts on the inner peripheral surface of the filter 90 so that it does not pass through the inside of the filter 90 through the gap between the lower end of the filter 90 and the bottom plate portion 11. Prevent it from leaking out.

The lower side pressing member 70 is formed by, for example, pressing a metal plate-shaped member, and is preferably a steel plate such as ordinary steel or special steel (for example, a cold-rolled steel plate, a stainless steel plate, or the like). ) Is composed of members.

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

As shown in FIG. 1, the upper shell 20 is assembled so as to cover the lower shell 10, and the upper shell 20 is joined to the lower shell 10 so as to be via the gas generating agent 61 as shown in FIG. A part of the force A applied to the leaf spring portion 75 on the bottom plate portion 11 side is transmitted to the upright portion 76 via the leaf spring portion 75 which is the connecting portion 74, and the upright portion 76 is transmitted to the upright portion 76 of the filter 90. The urging force A1 elastically urges the inner peripheral surface. On the other hand, as described above, a part of A2 in which the force A applied from the bottom plate portion 11 to the second contact portion 72 remains, the standing portion 76 loses its place without contacting the filter 90, and the leaf spring It is a force that elastically deforms the portion 75 toward the bottom plate portion 11. As a result, the leaf spring portion 75 is elastically deformed into the curved shape as described above, and the restoring force is elastically directed toward the central portion side and the top plate portion 21 side of the combustion chamber 60. It will act as a urging force B2.

Therefore, the lower side pressing member 70 is arranged in contact with the standing portion 76 in a state of being elastically urged on the inner peripheral surface of the filter 90 with a predetermined urging force A1, and the leaf spring portion 75 thereof is arranged. The gas generating agent 61 is contact-arranged in a state of being elastically urged with a predetermined urging force A2. Therefore, the gas generating agent 61 composed of the plurality of granular compacts loaded in the combustion chamber 60 is held in a state of being elastically urged mainly toward the bottom plate portion 11 side by the lower side pressing member 70. Crushing of the gas generating agent 61 at the time of non-operation can be prevented. Further, as the pressure in the combustion chamber 60 increases due to the gas generation during operation, the elastic urging forces A1 and A2 increase. Therefore, the lower side pressing member 70, the first contact portion 71 of the filter 90, the lower side pressing member 70, and the second contact portion 72 of the bottom plate portion 11 are firmly fixed to pass through the inside of the filter 90. Prevent it from leaking out without doing it.

As described above, in the present embodiment, a molded product formed by bending a metal plate-shaped member is used as the lower side pressing member 70. As a result, the lower side pressing member 70 has an appropriate elasticity, and the magnitude of the above-mentioned urging force B2 is the shape of the lower side pressing member 70 in the non-assembled state and the lower side pressing member 70. It is mainly determined by the relative relationship between the dimension of the non-assembled state and the dimension of the filter 90 into which the lower side pressing member 70 is inserted.

As shown in FIG. 1, an upper filter support member 80 is arranged 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-shaped shape, and is a cylindrical third contact portion 81 that abuts on the inner peripheral surface of the axial end portion located on the top plate portion 21 side of the filter 90. And a disk-shaped fourth contact portion 82 extending inward from the third contact portion 81.

The upper filter support member 80 is arranged so as to cover the boundary portion between the filter 90 and the top plate portion 21 so as to cover the boundary portion between the filter 90 and the top plate portion 21. As a result, the upper filter support member 80 is located between the top plate portion 21 and the gas generating agent 61 in the vicinity of the end portion of the combustion chamber 60.

During operation of the upper filter support member 80, the gas generated in the combustion chamber 60 flows 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. It functions as an outflow prevention means to prevent it from being stowed away. Like the lower side pressing member 70, the upper side filter supporting member 80 is formed by, for example, pressing a metal plate-shaped member, and is preferably a steel plate such as ordinary steel or special steel (preferably a steel plate such as ordinary steel or special steel. For example, it is composed of a member made of cold-rolled steel sheet, stainless steel sheet, etc.).

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

As shown in FIGS. 3 and 4, the gas generator 1B in the present embodiment has a different structure of the lower side holding member 70 when compared with the gas generator 1A in the first embodiment.

As shown in FIG. 4, the lower side pressing member 70 is formed by bending a metal plate-shaped member, so that the lower side pressing member 70 comes into contact with the inner peripheral 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 connecting portion 74 that connects the first contact portion 71 and the second contact portion 72 are formed.

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

As shown in FIG. 3, the upper shell 20 is assembled so as to cover the lower shell 10, and the upper shell 20 is joined to the lower shell 10 so as to be via the gas generating agent 61 as shown in FIG. A part of the force A applied to the leaf spring portion 75 on the bottom plate portion 11 side is transmitted to the first contact portion 71 via the leaf spring portion 75 which is the connecting portion 74, and the first contact portion 71 Is an urging force A1 that elastically urges the filter 90 toward the inner peripheral surface of the filter 90. On the other hand, as described above, a part of A2 in which the force A applied from the bottom plate portion 11 to the second contact portion 72 remains is lost due to the contact of the first contact portion 71 with the filter 90 and is connected. It is a force that elastically deforms the leaf spring portion 75, which is the portion 74, toward the bottom plate portion 11. As a result, the leaf spring portion 75 is elastically deformed into the curved shape as described above, and the restoring force acts as an urging force B1 that elastically biases the gas generating agent 61 toward the central portion side. And, it acts as an urging force B2 elastically urging toward the top plate portion 21 side of the combustion chamber 60.

Therefore, the lower side pressing member 70 is arranged in contact with the first contact portion 71 in a state where the first contact portion 71 is elastically urged on the inner peripheral surface of the filter 90 with a predetermined urging force A1 and the leaf spring portion thereof. The 75 is contact-arranged with the gas generating agent 61 in a state of being elastically urged with a predetermined urging force A2. Therefore, the gas generating agent 61 composed of the plurality of granular compacts loaded in the combustion chamber 60 is held in a state of being elastically urged mainly toward the bottom plate portion 11 side by the lower side pressing member 70. Crushing of the gas generating agent 61 at the time of non-operation can be prevented. Further, as the pressure in the combustion chamber 60 increases due to the gas generation during operation, the elastic urging forces A1 and A2 increase. Therefore, the lower side pressing member 70, the first contact portion 71 of the filter 90, the lower side pressing member 70, and the second contact portion 72 of the bottom plate portion 11 are firmly fixed to pass through the inside of the filter 90. Prevent it from leaking out without doing it.

As described above, in the present embodiment, a molded product formed by bending a metal plate-shaped member is used as the lower side pressing member 70. As a result, the lower side pressing member 70 has appropriate elasticity, and the magnitudes of the above-mentioned urging forces B1 and B2 are the shape of the lower side pressing member 70 in the non-assembled state and the lower side pressing member 70. It is mainly determined by the relative relationship between the dimension of the member 70 in the non-assembled state and the dimension of the filter 90 into which the lower side pressing member 70 is inserted.

As shown in FIG. 5, in the non-assembled state, the first contact portion 71 of the lower side pressing member 70 has a tubular shape, and the second contact portion 72 has an annular shape. The leaf spring portion 75, which is the connecting portion 74 thereof, has a hollow truncated cone-shaped curved plate shape that is convex from the axial end portion of the first contact portion 71 toward the second contact portion 72 side. have.

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

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

As a result, when the lower side pressing member 70, which will be described later, is assembled to the filter 90, the outer peripheral surface of the first contact portion 71 surely contacts the inner peripheral surface of the filter 90, and the second contact portion 72 Is pushed by the bottom plate portion 11, and the force A2 applied to the second contact portion 72 is sufficiently applied to the first contact portion 71 and the leaf spring portion 75 to become the force A1, and the above-mentioned urging force B1. B2 will be obtained moderately.

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

As described above, in the gas generator 1B of the present embodiment, the extended bottom portion 54 of the cup-shaped member 50 has the second contact portion 72 forming the connecting 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 side pressing member 70 while being overlapped with each other. Then, as described above, the cup-shaped member 50 is fixed to the lower shell 10 via the inner covering portion 31 as a protruding portion of the holding portion 30 integrated with the lower shell 10 by insert molding. As a result, the cup-shaped member 50 is fixed relatively immovably with respect to the housing via the lower side pressing member 70 and the holding portion 30. The second contact portion 72 does not need to be overlapped with the bottom plate portion 11 via the extended bottom portion 54, and the second contact portion 72 and the bottom plate portion 11 may come into direct contact with each other.

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

When a vehicle equipped with a gas generator in the present embodiment collides, the collision is detected by a collision detection means separately provided in the vehicle, and based on this, electricity is supplied from a control unit separately provided in the vehicle. Activates the igniter 40. The gunpowder 57 housed in the firebox 56 is ignited and burned by a flame generated by the operation of the igniter 40 to generate a large amount of heat particles. The combustion of the explosive agent 57 causes the cup-shaped member 50 to burst or melt, and the above-mentioned heat particles flow into the combustion chamber 60.

The heat particles that have flowed in ignite the gas generating agent 61 contained in the combustion chamber 60 and burn it to generate a large amount of gas. The gas generated in the combustion chamber 60 passes through the inside of the filter 90, and at that time, heat is taken away by the filter 90 and cooled, and the residue contained in the gas is removed by the filter 90 to remove the gap 25. Flow into.

As the pressure in the space inside the housing rises, the sealing tape 24 that closed the gas outlet 23 provided in the upper shell 20 is torn, and the gas flows to the outside of the housing through the gas outlet 23. It is ejected. The ejected gas is introduced into an airbag provided adjacent to the gas generator to inflate and deploy the airbag.

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

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 portion 30 as a resin molding portion is formed on the bottom plate portion 11 of the lower shell 10, whereby the igniter 40 is fixed to the protruding tubular portion 13 of the lower shell 10.

Next, as shown in FIG. 6, in the state of being positioned by the jig 100, the inside of the cup-shaped member 50 manufactured by press molding in advance is filled with a predetermined amount of the flame-transmitting agent 57, and the lower side presser is pressed. A portion of the lower shell 10 in a fixed state in the vicinity of the protruding tubular portion 13 is inserted from the opening end side of the cup-shaped member 50 along the inside of the cup-shaped member 50. Here, the insertion operation is performed in a state where both the cup-shaped member 50 and the lower shell 10 are turned upside down in order to prevent the explosive charge 57 from spilling from the cup-shaped member 50. ..

Next, the lower side pressing member 70 manufactured in advance by press molding is inserted into the lower side shell 10 in which the cup-shaped member 50 is assembled to the igniter 40. At that 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 externally inserted so that its inner peripheral surface abuts on the outer peripheral surface of the first contact portion 71 of the lower side pressing member 70. As a result, the filter 90 is supported by the lower side pressing member 70, and the filter 90 is assembled to the lower side shell 10. The extended bottom portion 54 of the cup-shaped member 50 is in contact with the second contact portion 72 of the lower side pressing member 70.

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

Next, as shown in FIG. 8, the upper filter support member 80 is assembled to the filter 90 in a state of being positioned by 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, the upper shell 20 is assembled so as to cover the lower shell 10, and the upper shell 20 is joined to the lower shell 10 so as to be shown in FIG. As shown, the production of the gas generator 1B is completed. At that time, the lower pressing member 70 is pressed by the press fitting of the upper shell 20, so that the elastic urging force A of the lower pressing member 70 acts, and the restoring force B is applied while the drug capacity is increased. The gas generating agent 61 is suppressed.

As described above, by using the gas generator 1B in the present embodiment, the cup-shaped member 50 is securely fixed to the lower shell 10 and is easy to assemble. The cup-shaped member 50 can be fixed to the lower shell 10.

Here, in the gas generators 1A and 1B in the present embodiment and 1C and 1D described later, even when the enhancer cup, which is a fragile member having relatively low mechanical strength, is used as the cup-shaped member 50, Since it is not necessary to press-fit this into the holding portion 30 or the like, it is not necessary to strictly control the external dimensions of the enhancer cup as the cup-shaped member 50 more than necessary, and in this respect, the manufacturing cost can be significantly reduced. Become. Further, since it is not necessary to press-fit the enhancer cup as the cup-shaped member 50 into the holding portion 30 or the like, problems such as buckling do not occur.

Further, in the gas generators 1A to 1D of the present embodiment, since it is not necessary to provide the flange portion for caulking on the lower shell 10, no cutting process or the like for forming the flange portion is required. In this respect as well, the manufacturing cost can be significantly reduced.

Further, by using the gas generators 1A to 1D in the present embodiment, as described above, the exposed surface inside the housing of the holding portion 30 made of the resin molded portion is surrounded by the lower side pressing member 70. can do. By adopting this configuration, it is possible to prevent the holding portion 30 made of the resin forming portion from being exposed to flames during operation, so that harmful gas components such as carbon monoxide are significantly generated. An effect that can be suppressed can also be obtained.

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

(Embodiment 3)
FIG. 11 is a schematic view of the gas generator 1C according to the third embodiment of the present invention. The configuration of the gas generator 1C according to the third embodiment will be described with reference to FIG.

As shown in FIG. 11, the gas generator 1C according to the third embodiment has 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 the member 80a is provided.

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

As a result, the gas generating agent 61 is filled so that the gas generating agent 61 comes into contact with the bottom surface of the cup-shaped portion 85, so that the jig 100 becomes unnecessary 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-like shape with the side wall portion of the cup-shaped portion 85, the fourth contact portion 82, and the connecting portion 83. .. As described above, there is a gap of the upper gap portion 86 between the fourth contact portion 82 and the disc portion corresponding to the bottom plate portion 11 of the cup-shaped portion 85, and the gas generating agent 61 is provided with an elastic shape. Can be urged and held by the upper side pressing member 80a.

(Embodiment 4)
FIG. 12 is a schematic view of the gas generator 1D according to the fourth embodiment of the present invention. The configuration of the gas generator 1D according to the fourth embodiment will be described with reference to FIG.

As shown in FIG. 12, the gas generator 1D in the fourth embodiment has a structure different from that of the cup-shaped member 50 when compared with the gas generator 1A in the first embodiment described above. Is different.

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

As a result, since the cup-shaped member 50 is fixed without being sandwiched between the lower side pressing member 70 and the bottom plate portion 11, 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 is used. Can be filled.

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

As shown in FIG. 13, the lower filter support member 70 according to the first 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 cut-up portion 72a. ing. Specifically, in the first modification, twelve cut-up portions 72a are provided at equal intervals along the circumferential direction of the second contact portion 72, and each of them is a substantially trapezoidal tongue piece. It is configured. That is, in the first modification, the second contact portion 72 exists as a plurality of tongue piece-shaped bottom portions. Then, as shown in FIG. 14, the connecting portion 74 between the first contact portion 71 and the second contact portion 72 is cut and raised formed in the annular plate portion 77 and the annular plate portion 77 extending from the tubular portion. The portion 72a is composed of an erection portion 76 erected from the radial outer end surface of the annular plate portion 77. The upright portion 76 does not need to come into contact with the first contact portion 71 with the inner peripheral surface of the filter 90, and can be appropriately selected.

In this case, as shown in FIG. 14, by cutting up a part of the lower side pressing member 70, the space created by cutting up when the upper shell 20 is press-fitted is elastically deformed, so that the lower side gap portion 78 Will fill the void. Due to the reaction force of the cut-up portion 72a, the elastically urging restoring force acts on the gas generating agent 61. The size of the cut-up portion 72a is preferably smaller than the diameter of the gas generating agent 61, whereby the gas generating agent 61 can be prevented from flowing into the space of the lower gap portion 78, and the elasticity of the connecting portion 74 can be prevented. It is configured so as not to interfere with the grant.

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

In the first modification, the cut-up portion 72a is composed of a tongue piece, but the shape is not limited to this. For example, it may be configured by a shape such as a rectangle, a circle, or a trapezoid.

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

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 twelve protrusions 72b are provided at equal intervals along the circumferential direction of the annular plate portion 77. Each is composed of bowls. 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. Then, as shown in FIG. 16, the connecting portion 74 between the first contact portion 71 and the second contact portion 72 has a bowl shape formed on the annular plate portion 77 and the annular plate portion 77 extending from the tubular portion. It is composed of a protruding portion 72b of the above and a standing portion 76 erected from the radial outer end surface of the annular plate portion 77. The upright portion 76 does not need to come into contact with the first contact portion 71 with the inner peripheral surface of the filter 90, and can be appropriately selected.

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

In the second modification, 12 protrusions 72b are provided at equal intervals along the circumferential direction of the annular plate portion 77, but any number of protrusions 72b may be present. It does not matter what the arrangement is. Here, it is preferable that the protrusions 72b are provided at equal intervals along the circumferential direction, but the present invention is not limited to this.

In the second modification, the protrusion 72b is formed in a bowl shape, but the shape is not limited to this. For example, it may be formed in a shape such as a polygonal columnar shape, a polygonal pyramid shape, a columnar shape, or a conical shape.

Even when the configuration as in the first to second modifications described above is adopted, the same effect as the effect described in the above-described embodiment can be obtained.

As described above, the shape, orientation, number, size, formation position, etc. of the locking portion described in the above-described embodiment are various as long as the cup-shaped member is locked by the locking portion. The change is possible. Further, the shape of the cup-shaped member of the portion 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 modification, by press-fitting the lower side pressing member 70 into the holding portion 30, it cannot be moved relative to the lower shell 10 via the holding portion 30. Although the case where the lower side holding member 70 is fixed to the lower side shell 10 is press-fitted into the protruding tubular portion 13 of the lower side shell 10, the lower side holding member 70 cannot be moved relative to the lower side shell 10. The lower shell member 70 may be fixed to the lower shell 10 at a predetermined position so as to be relatively immovable with respect to the lower shell 10. Further, at the time of insert molding of the holding portion 30, the holding portion 30 may be integrally molded so as to be fixed not only to the lower shell 10 but also to the lower pressing member 70. As described above, various methods can be adopted for fixing the lower holding member 70 to the lower shell.

Further, in the above-described embodiment and its modification, the case where the connecting portion 74 of the lower side pressing member 70 is configured to cover the entire exposed surface inside the housing of the holding portion 30 will be illustrated and described. I did, but it doesn't have to be configured that way.

Further, in the above-described embodiment and its modification, the case where the lower shell 10 and the upper shell 20 are formed of a press-molded product formed by pressing a metal member is illustrated. The lower shell 10 and the upper shell 20 formed by a combination of press working and other machining (forging, drawing, cutting, etc.) are not necessarily limited to this, and may be used. However, the lower shell 10 and the upper shell 20 formed only by the above other processing may be used.

Further, the shapes of the respective parts shown in the above-described embodiment and the modified examples thereof can be changed as appropriate as long as the gist of the present invention is not deviated.

As described above, the above-described embodiment and its modifications disclosed this time are exemplary in all respects and are not restrictive. The technical scope of the present invention is defined by the scope of claims and includes all modifications within the meaning and scope equivalent to the description of the scope of claims.

1A, 1B, 1C, 1D gas generator, 10 lower shell, 11 bottom plate, 12 peripheral wall, 13 protruding cylinder, 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, 52 side wall, 53 tubular, 54 extended bottom, 55 tip, 56 fire chamber, 57 fire agent, 58 flange, 60 combustion chamber, 61 gas generator , 65 Insertion opening, 70 Lower side holding member, 71 1st contact part, 72 2nd contact part, 72a cut-up part, 72b protrusion part, 73 tubular part, 74 connection part, 75 leaf spring part, 76 Standing part, 76a Cylindrical part, 76b Expanded cylinder part, 77 Ring plate part, 78 Lower side gap part, 80 Upper side filter support member, 80a Upper side holding member, 81 3rd contact part, 82 4th Contact part, 83 connection part, 84 leaf spring part, 85 cup-shaped part, 86 upper side gap part, 90 filter, 100 jig

Claims (6)

It is composed of 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 end of the peripheral wall portion, and includes a combustion chamber containing a gas generating agent inside. With the housing
An igniter that is assembled to the bottom plate and contains an igniter that ignites during operation.
A cylindrical filter located inside the housing and arranged so as to surround the combustion chamber in the radial direction of the housing.
It is arranged 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, supports the filter, and is fixed so as to be relatively immovable with respect to the housing. Lower side holding member and
It has a substantially tubular shape with an open end on the bottom plate side, and includes a firebox containing a firebox inside, and faces the combustion chamber so that the firebox faces the ignition section. With a protruding cup-shaped member,
The cup-shaped member extends outward from the top wall portion and the side wall portion defining the fire transmission room and the end portion of the side wall portion on the bottom plate portion side along the inner bottom surface of the bottom plate portion. Has an extended bottom and
The lower side pressing member includes a standing portion that covers the inner peripheral surface of the filter located on the bottom plate portion side, a cylindrical portion that is arranged so as to cover the cup-shaped member, and the standing portion and the tubular shape. Equipped with a connection part to connect the parts
A gas generator in which the connection is elastically deformable and includes a second contact that contacts the housing or the extension bottom. The extended bottom portion is fixed by being sandwiched between the second contact portion of the lower side pressing member and the housing.
The gas generator according to claim 1, wherein the connecting portion has an inclined shape that inclines toward the top plate portion side from the second contact portion toward the outer side in the radial direction of the inner peripheral surface. The lower side pressing member includes a first contact portion that contacts the inner peripheral surface of the filter located on the bottom plate portion side, a cylindrical portion that is arranged so as 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 connecting the portion and the tubular portion. The extended bottom portion is fixed by being sandwiched between the second contact portion of the lower side pressing member and the housing.
The gas generator according to claim 1 or 3, wherein the connecting portion has a tongue piece-shaped raised portion or a bowl-shaped protrusion. The lower side pressing member has a cylindrical portion that is located near the axial end of the first contact portion and has a uniform diameter.
The pressing member has a diameter-expanded tubular portion that is located at a portion closer to the axial end portion that is located on the side opposite to the axial end portion and whose diameter increases toward the tip end side.
The outer diameter of the cylindrical portion is equal to or smaller than the inner diameter of the filter.
The maximum outer diameter of the enlarged diameter cylinder portion is configured to be larger than the inner diameter of the filter.
The gas generator according to any one of claims 1, 3 or 4. A resin holding portion for fixing the igniter to the bottom plate portion is further provided.
The holding portion has a protruding portion that protrudes toward the combustion chamber side.
The connecting portion has a cylindrical portion that extends along the axial direction of the housing and covers the outer peripheral surface of the protruding portion.
Any of claims 1 to 5, wherein the lower holding member is fixed to the housing relatively immovably via the holding portion by press-fitting the tubular portion into the protruding portion. The gas generator described in the cylinder.

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