JP2014237389A - Filter for gas generator and gas generator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a filter for a gas generator which is light-weight and provides high cooling performance and slug collection performance.SOLUTION: A filter 70A for a gas generator has a hollow cylindrical shape formed by a wound body of a metal wire material 71. The metal wire material 71 is formed of a long member whose cross sections at any positions in an extending direction match mutually. On a surface of the metal wire material 71, a groove part 72 extending in the extending direction is provided. The maximum external dimension of the metal wire material 71 along a depth direction of the groove part 72 is smaller than the maximum external dimension of the metal wire material 71 along a width direction of the groove part 72. The groove part 72 faces a hollow part 73 side of the filter 70A for a gas generator.

Description

  The present invention relates to a gas generator and a filter for a gas generator (hereinafter also simply referred to as a filter) provided in the gas generator, and more specifically, a gas generator incorporated in an occupant protection device and the gas generator. Relates to a filter for a gas generator.

  2. Description of the Related Art Conventionally, airbag devices, which are occupant protection devices, have been widely used from the viewpoint of protecting occupants such as automobiles. The airbag device is equipped for the purpose of protecting the occupant from the impact generated when the vehicle or the like collides. The airbag is inflated and deployed instantaneously when the vehicle or the like collides, so that the airbag becomes a cushion of the occupant. It is to catch the body.

  The gas generator is incorporated in the airbag device, and igniters (squibs) are ignited by energization from the control unit (actuator) in the event of a vehicle collision, etc., and the gas generating agent is combusted by the flame generated in the igniter. This is a device that instantaneously generates the gas and thereby inflates and deploys the airbag. Note that the airbag device is mounted on, for example, an automobile steering wheel or an instrument panel.

  Usually, the gas generator is provided with a filter for the purpose of cooling the gas generated in the combustion chamber and collecting the residue (slag) contained in the gas. The filter is generally composed of a hollow cylindrical member formed of a wound body or a braided body of metal wire, and gas passes through the filter from the hollow portion located inside to the outside in the radial direction. And accommodated in a space inside the housing.

  Documents disclosing the gas generator filter having the above-described configuration include, for example, Japanese Unexamined Patent Application Publication No. 2002-301317 (Patent Document 1) and Japanese Unexamined Patent Application Publication No. 2009-190656 (Patent Document 2).

  Among these, in Patent Document 1, a plurality of parts that are spaced apart from each other in the axial direction on the outer peripheral surface of the metal wire having a circular cross section by intermittently forming recesses along the extending direction. For a gas generator manufactured by manufacturing a metal wire having a concave portion, forming a braided body by weaving the metal wire, and pressing the braided body into a hollow cylinder by pressing. A filter is disclosed.

  Further, in Patent Document 2, a plurality of groove portions are formed in parallel so as to continuously extend along the extending direction of the metal wire having a circular cross section, so that the outer peripheral surface has a radial shape in cross section. A filter for a gas generator manufactured by manufacturing a metal wire material provided with a protrusion, forming a braided body by weaving this metal wire material, and further compressing the braided body into a hollow cylindrical shape Is disclosed, and another filter for a gas generator manufactured by winding the above-described metal wire into a hollow cylindrical shape without weaving is also disclosed.

JP 2002-301317 A JP 2009-190656 A

  In recent years, there has been a strong demand for downsizing and weight reduction of gas generators. Therefore, gas generator filters are also required to be reduced in size and weight. However, the gas generator filters disclosed in Patent Documents 1 and 2 are disadvantageous in terms of reduction in size and weight. There is a problem that becomes.

  That is, since the gas generator filters disclosed in Patent Documents 1 and 2 are each composed of a metal wire having a substantially circular cross-sectional shape, the wound or braided body of the metal wire is used. All of the gas generator filters configured as described above tend to increase in thickness. When attempting to obtain the desired cooling performance and slag collection performance, the increase in size and weight is inevitable. End up.

  Accordingly, the present invention has been made to solve the above-described problems, and provides a gas generator filter that is small and lightweight, and that can provide high cooling performance and slag collection performance, and a gas generator including the same. For the purpose.

  The filter for gas generators based on this invention is a hollow cylindrical thing comprised by the wound body or braided body of the metal wire. The metal wire is made of a long member whose cross-sectional shapes at arbitrary positions in the extending direction of the metal wire are mutually matched, and a groove portion extending along the extending direction is formed on the surface of the metal wire. Is provided. The maximum outer dimension of the metal wire along the depth direction of the groove is smaller than the maximum outer dimension of the metal wire along the width direction of the groove, and the groove is on the hollow portion side of the gas generator filter. Facing.

  In the gas generator filter according to the present invention, the metal wire may have a bent plate shape, and in that case, the groove is defined by a bent portion of the metal wire. It is preferable that

  In the gas generator filter according to the present invention, the metal wire may have a curved plate shape, and in that case, the groove is defined by a curved portion of the metal wire. It is preferable that

  In the filter for a gas generator according to the present invention, the metal wire may have a substantially flat plate shape, and in that case, the groove portion has a wide main surface of the metal wire. It is preferable that it is provided in one of these.

  The gas generator based on this invention is equipped with the filter for gas generators based on the said invention.

  ADVANTAGE OF THE INVENTION According to this invention, it can be set as the gas generator provided with the filter for gas generators with which it is small and lightweight, and can obtain high cooling performance and slag collection performance.

It is the schematic of the gas generator in Embodiment 1 of this invention. It is a schematic perspective view of the filter for gas generators in Embodiment 1 of this invention. It is a figure which shows the shape of the metal wire which comprises the filter for gas generators shown in FIG. It is a figure which shows typically the flow of the gas which passes the filter for gas generators shown in FIG. It is a schematic diagram which shows the flow of the gas shown in FIG. 4 in detail. It is a figure which shows the process of shape-processing from a metal strand to the metal wire shown in FIG. It is a figure which shows the winding process which manufactures the filter for gas generators shown in FIG. 2 from the metal wire shown in FIG. It is a schematic perspective view of the filter for gas generators in Embodiment 2 of this invention. It is a figure which shows the shape of the metal wire which concerns on a 1st thru | or 4th modification.

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

(Embodiment 1)
FIG. 1 is a schematic diagram of a gas generator according to Embodiment 1 of the present invention. First, with reference to this FIG. 1, the gas generator 1 in this Embodiment is demonstrated.

  As shown in FIG. 1, the gas generator 1 in the present embodiment has a short, substantially cylindrical housing that is closed at both ends in the axial direction. In the housing space provided inside the housing, The holding unit 30, the igniter 40, the cup-shaped member 50, the transfer agent 56, the gas generating agent 61, the lower holding member 62, the upper holding member 63, the cushion material 64, the filter 70A, and the like are accommodated as internal components. It consists of A combustion chamber 60 in which the gas generating agent 61 among the above-described internal components is mainly housed is located in the housing space provided inside the housing.

  The short, substantially cylindrical housing includes a lower shell 10 and an upper shell 20. Each of the lower shell 10 and the upper shell 20 is made of a press-formed product formed by, for example, pressing a rolled metal plate member. As the metal plate-like members 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 a tensile strength of 440 MPa or more and 780 MPa or less. A so-called high-tensile steel plate that does not cause breakage or the like even when stress is applied is preferably used.

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

  At the center of the bottom plate portion 11 of the lower shell 10, there is provided a protruding cylindrical portion 13 that protrudes toward the top plate portion 21, so that the center portion of the bottom plate portion 11 of the lower shell 10 has a central portion. A recess 14 is formed. The projecting cylindrical portion 13 is a portion to which the igniter 40 is fixed via the holding portion 30 described above, and the recessed portion 14 is a portion that becomes a space for providing the female connector portion 34 in the holding portion 30. .

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

  As shown in FIG. 1, 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 therein an igniting agent that generates a flame by igniting and burning during operation, and a resistor for igniting the igniting agent. The pair of terminal pins 42 are connected to the ignition unit 41 to ignite the igniting agent.

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

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

  When a collision is detected, a predetermined amount of current flows through the resistor via the terminal pin 42. When a predetermined amount of current flows through the resistor, Joule heat is generated in the resistor, and the ignition agent starts burning. The high temperature flame generated by the combustion ruptures the squib cup containing the igniting agent. The time from when the current flows through the resistor until the igniter 40 is activated is generally 2 milliseconds or less when a nichrome wire is used as the resistor.

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

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

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

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

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

  The holding part 30 is fixed to the bottom plate part 11 on the surface of each of the inner covering part 31, the outer covering part 32 and the connecting part 33 on the bottom plate part 11 side. Further, the holding unit 30 is fixed to the side surface and the lower surface of the portion near the lower end of the ignition unit 41 of the igniter 40 and the surface of the portion near the upper end of the terminal pin 42 of the igniter 40. As a result, the opening 15 is completely embedded by the terminal pin 42 and the holding part 30, and the sealing property at the part is ensured, thereby ensuring the airtightness of the space inside the housing. Since the opening 15 is formed in an oval shape in plan view as described above, by embedding the opening 15 in the connecting portion 33, the opening 15 and the connecting portion 33 are connected to the holding portion 30. It also functions as a detent mechanism that prevents the bottom plate portion 11 from rotating.

  A female connector portion 34 is formed on a portion of the holding portion 30 facing the outside of the outer covering portion 32. The female connector portion 34 is a portion for receiving a male connector (not shown) of a harness for connecting the igniter 40 and a control unit (not shown), and the bottom plate portion 11 of the lower shell 10. It is located in the hollow part 14 provided in. In the female connector portion 34, a portion near the lower end of the terminal pin 42 of the igniter 40 is disposed so as to be exposed. A male connector is inserted into the female connector portion 34, thereby realizing electrical continuity between the harness core wire and the terminal pin 42.

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

  In this way, since the cured adhesive layer is positioned between the bottom plate portion 11 and the holding portion 30, the holding portion 30 made of the resin molded portion can be more firmly fixed to the bottom plate portion 11. It becomes possible. Therefore, 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 part 11, it is possible to ensure higher sealing performance in the part.

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

  In addition, although the example of a structure at the time of enabling fixation of the igniter 40 with respect to the lower side shell 10 by injection-molding the holding | maintenance part 30 which consists of a resin molding part was illustrated here, the igniter 40 with respect to the lower side shell 10 is shown. It is possible to use other alternative means for fixing.

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

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

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

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

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

  In addition to the above, the cup-shaped member 50 is made of a metal member having high mechanical strength such as iron or copper, and has an opening in the side wall portion 52. It is also possible to use one having a seal tape attached so as to close the opening. Further, the fixing method of the cup-shaped member 50 is not limited to the fixing method using the lower holding member 62 described above, and other fixing methods may be used.

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

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

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

  The shape of the molded body of the gas generating agent 61 includes various shapes such as granular shapes, pellet shapes, granular shapes such as columnar shapes, and disk shapes. In addition, in the cylindrical shape, a porous (for example, a single-hole cylindrical shape or a porous cylindrical shape) having a through hole inside the molded body is also used. These shapes are preferably selected as appropriate according to the specifications of the airbag apparatus in which the gas generator 1 is incorporated. For example, the shape in which the gas generation rate changes with time during the combustion of the gas generating agent 61 is selected. It is preferable to select an optimal shape according to the specifications. In addition to the shape of the gas generating agent 61, it is preferable to appropriately select the size and filling amount of the molded body in consideration of the linear combustion rate, the pressure index, etc. of the gas generating agent 61.

  In a space surrounding the combustion chamber 60 in the radial direction of the housing, a filter 70A is disposed along the inner periphery of the housing. The filter 70A has a hollow cylindrical shape, and is disposed so that the central axis thereof substantially matches the axial direction of the housing, whereby the diameter of the combustion chamber 60 in which the gas generating agent 61 is accommodated. Surrounding in direction. Here, the filter 70 </ b> A has a relatively large-diameter short cylindrical shape so as to conform to the shape of the gas generator 1.

  When the gas generated in the combustion chamber 60 passes through the filter 70A, the filter 70A functions as a cooling unit that cools the gas by taking away the high-temperature heat of the gas, and the slag contained in the gas. It also functions as a removing means for removing. The details of the filter 70A will be described later.

  A plurality of gas outlets 23 are provided in the peripheral wall portion 22 of the upper shell 20 at a portion facing the filter 70A. The gas outlet 23 is for leading the gas that has passed through the filter 70A to the outside of the housing. A seal tape 24 is affixed to the main surface located on the filter 70 </ b> A side of the peripheral wall portion 22 of the upper shell 20 so as to close the gas outlet 23. As this sealing tape 24, an aluminum foil or the like having an adhesive member applied on one side is used. Thereby, the airtightness of the combustion chamber 60 is ensured.

  A lower holding member 62 is disposed in the combustion chamber 60 in the vicinity of the end located on the bottom plate 11 side. The lower holding member 62 has an annular shape and is disposed so as to cover the boundary portion between the filter 70 </ b> A and the bottom plate portion 11. The lower holding member 62 positions and holds the filter 70 </ b> A by contacting the inner peripheral surface located on the bottom plate portion 11 side of the filter 70 </ b> A, and the tip end portion 54 of the cup-shaped member 50 with the bottom plate portion 11. The cup-shaped member 50 is held by sandwiching.

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

  When the lower holding member 62 and the upper holding member 63 are in operation, the gas generated in the combustion chamber 60 does not pass through the inside of the filter 70A and the gap between the lower end of the filter 70A and the bottom plate portion 11 and the filter. It prevents that it flows out of the clearance gap between the upper end of 70A, and the top-plate part 21. FIG. The lower holding member 62 and the upper holding member 63 are formed by, for example, pressing a metal plate-like member, and preferably a steel plate such as ordinary steel or special steel (for example, cold rolling) Steel plate or stainless steel plate).

  An annular cushion material 64 is arranged inside the upper holding member 63 so as to contact the gas generating agent 61 accommodated in the combustion chamber 60. Thereby, the cushion material 64 is located between the top plate portion 21 and the gas generating agent 61 in the portion of the combustion chamber 60 on the top plate portion 21 side, and the gas generating agent 61 is directed toward the bottom plate portion 11 side. Is pressing.

  The cushion material 64 is provided for the purpose of preventing the gas generating agent 61 made of a molded body from being crushed by vibration or the like, and is preferably a ceramic fiber molded body, rock wool, foamed resin (for example, (Such as foamed silicone, foamed polypropylene, foamed polyethylene, etc.), chloroprene, and a member made of rubber typified by EPDM.

  Next, the operation of the gas generator 1 in the above-described embodiment will be described with reference to FIG.

  When a vehicle equipped with the gas generator 1 according to the present embodiment collides, a collision is detected by a collision detection unit provided separately in the vehicle, and based on this, a control unit provided separately in the vehicle The igniter 40 is activated by energization. The transfer charge 56 accommodated in the transfer chamber 55 is ignited and burned by the flame generated by the operation of the igniter 40 and generates a large amount of heat particles. The cup-shaped member 50 is ruptured or melted by the combustion of the charge transfer agent 56, and the aforementioned heat particles flow into the combustion chamber 60.

  The gas generating agent 61 accommodated in the combustion chamber 60 is ignited and burned by the flowing heat particles, and a large amount of gas is generated. The gas generated in the combustion chamber 60 passes through the inside of the filter 70A. At that time, the heat is taken away and cooled by the filter 70A, and the slag contained in the gas is removed by the filter 70A, so that the outside of the housing is removed. Flow into the periphery.

  As the internal pressure of the housing increases, the sealing by the sealing tape 24 that has closed the gas outlet 23 of the upper shell 20 is broken, and gas is jetted out of the housing through the gas outlet 23. The jetted gas is introduced into an airbag provided adjacent to the gas generator 1 to inflate and deploy the airbag.

  2 is a schematic perspective view of the gas generator filter in the present embodiment shown in FIG. 1, and FIG. 3 is a diagram showing the shape of the metal wire constituting the gas generator filter shown in FIG. Next, the gas generator filter in the present embodiment will be described in detail with reference to FIGS. 2 and 3.

  As shown in FIG. 2, the filter 70 </ b> A is configured by a hollow cylindrical winding body manufactured by winding a metal wire 71 having a predetermined shape. The filter 70A has a hollow portion 73 penetrating along the axial direction, and the hollow portion 73 constitutes a combustion chamber 60 in which the gas generating agent 61 is accommodated (see FIG. 1).

  The metal wire 71 constituting the filter 70A is wound several times along the radial direction of the filter 70A. Accordingly, the filter 70A has a structure in which the metal wire 71 is stacked in layers along the radial direction. The metal wire 71 is wound in an oblique direction so as to extend so as to intersect with both the circumferential direction and the axial direction of the filter 70A, and has one end portion and the other end portion in the axial direction. In FIG. 2, the winding direction is folded to form a mesh shape.

  In FIG. 2, for ease of understanding, only the surface portion of the outer peripheral surface side of the filter 70 </ b> A and the portion of the metal wire 71 located on the inner peripheral surface side of the filter 70 </ b> A are illustrated. In addition, the filter 70 </ b> A has a configuration in which a gap between the metal wire rods 71 in the illustrated portions is covered with a portion of the metal wire rods 71 located in the inner layer portion.

  As shown in FIG. 3, the metal wire 71 is composed of long members whose cross-sectional shapes at arbitrary positions in the extending direction coincide with each other, and on the surface thereof, in the extending direction. A groove portion 72 extending continuously along is provided.

  More specifically, in the filter 70A according to the present embodiment, the metal wire 71 includes a flat base 71a extending along the extending direction of the metal wire 71, and both ends of the flat base 71a. It includes a pair of flat projections 71b extending along the extending direction of the metal wire 71 by being erected, and the groove portion 72 described above is constituted by the base 71a and the pair of projections 71b. ing.

  From this standpoint, the metal wire 71 constituting the filter 70A in the present embodiment has a bent plate shape, and the groove 72 is defined by the bent portion of the metal wire 71. You can see that.

  The maximum outer dimension L1 of the metal wire 71 along the depth direction of the groove 72 is configured to be smaller than the maximum outer dimension L2 of the metal wire 71 along the width of the groove 72 (L1 <L2). That is, the distance L1 between the wider main surface where the groove portion 72 of the metal wire 71 is formed and the wider main surface where the groove portion 72 of the metal wire 71 is not formed is a pair of the metal wire 71. It is smaller than the distance L2 between the end faces.

  From this point of view, the metal wire 71 constituting the filter 70A according to the present embodiment has a substantially flat plate shape as a whole, and the groove 72 is a wide main portion of the metal wire 71. It can be seen that it is provided on one of the faces.

  Here, as shown in FIG. 2, in the filter 70A, the groove part 72 provided in the surface of the metal wire 71 mentioned above is comprised so that the hollow part 73 side of the said filter 70A may face. That is, the wide main surface on which the groove portion 72 of the metal wire 71 is formed is arranged so as to face the radially inner side of the filter 70A, and the groove portion 72 of the metal wire 71 is formed. The wider main surface that is not present is arranged to face the radially outer side of the filter 70A.

  Examples of the material of the metal wire 71 include stainless steel, steel, nickel alloy, copper alloy, and austenitic stainless steel is particularly preferable. The maximum outer dimension L1 of the metal wire 71 is preferably about 0.5 [mm] to 5.0 [mm], and the maximum outer dimension L2 of the metal wire 71 is greater than the maximum outer dimension L1. Is preferably about 0.5 [mm] to 5.0 [mm]. The filter 70 </ b> A may be composed of one metal wire 71 or may be composed of a plurality of metal wires 71.

  FIG. 4 is a diagram schematically showing the flow of gas passing through the gas generator filter shown in FIG. 2, and FIG. 5 is a schematic diagram showing the gas flow shown in FIG. 4 in more detail. Next, with reference to these FIG. 4 and FIG. 5, it demonstrates in full detail about the gas flow at the time of the action | operation of the gas generator in this Embodiment.

  As described above, when the gas generator 1 is in operation, the gas generated in the combustion chamber 60 passes through the filter 70A and reaches the gas outlet 23 (see FIG. 1). At that time, as shown in FIG. 4, the gas generated in the combustion chamber 60 enters the inside of the filter 70A from the hollow portion 73 side of the filter 70A (see the arrow AR1 shown in the figure), and is approximately the diameter of the filter 70A. After moving along the direction, it is discharged toward the outside of the filter 70A (see arrow AR2 shown in the figure).

  Here, as described above, in the gas generator 1 according to the present embodiment, the groove portion 72 provided on the surface of the metal wire 71 constituting the filter 70A is connected to the hollow portion 73 side (that is, the combustion chamber 60 side). It is suitable. Therefore, the flow path through which the gas passes inside the filter 70A is complicated, so that not only the contact area of the filter 70A with the gas increases, but also the gas blown into the groove 72 as shown in FIG. (In the figure, the flow of the gas is schematically indicated by an arrow AR11), but the gas flow is greatly disturbed by generating a minute vortex when the direction is changed in the groove 72. (In the figure, the flow of the disturbed gas is schematically indicated by arrows AR12 and AR13), and these together provide high cooling performance.

  In addition, as shown in FIG. 5, since the slag S contained in the gas blown to the groove 72 is efficiently collected on the surface of the groove 72, the slag S is separated from the groove 72 again. Can be prevented. Therefore, high slag collection performance is also obtained, and the discharge of slag to the outside of the gas generator 1 can be greatly reduced.

  Furthermore, in the filter 70 </ b> A according to the present embodiment, as described above, the maximum outer dimension L <b> 1 of the metal wire 71 along the depth direction of the groove 72 is the metal wire 71 along the width direction of the groove 72. Therefore, even when the metal wire 71 is stacked in the radial direction of the filter 70A, the total thickness can be reduced, and the desired cooling performance and slag collection performance can be achieved. Even if it is going to be obtained, the size reduction and weight reduction are achieved.

  Therefore, by using the filter 70A in the present embodiment, it is possible to obtain a filter for a gas generator that is small and lightweight and can obtain high cooling performance and slag collection performance. In addition, the gas generation in the present embodiment By using the device 1, a small, light and high performance gas generator can be obtained.

  FIG. 6 is a diagram showing a process of shape processing from a metal wire to the metal wire shown in FIG. 3, and FIG. 7 is a winding process for manufacturing the gas generator filter shown in FIG. 2 from the metal wire shown in FIG. FIG. Next, with reference to these FIG. 6 and FIG. 7, the specific manufacturing method of the filter for gas generators in this Embodiment mentioned above is demonstrated.

  In summary, the filter 70A according to the present embodiment summarizes the groove so that when the metal wire having a circular cross section is rolled into a substantially flat plate shape, the metal wire continuously extends along the extending direction thereof. The metal wire 71 having the shape as shown in FIG. 3 is manufactured, and the metal wire 71 is manufactured by winding it into a hollow cylindrical shape without weaving.

  As shown in FIG. 6, when rolling the metal wire 80, a rolling roll 100 </ b> A provided with a convex portion 101 extending in the circumferential direction at a predetermined position, and a concave portion extending in the circumferential direction at a predetermined position. A metal wire 71 is obtained by subjecting the metal wire 80 to shape processing using a rolling roll 100 </ b> B provided with 102.

  More specifically, the pair of rolling rolls 100A and 100B are arranged to face each other so that the convex part 101 and the concave part 102 face each other, and the pair of rolling rolls 100A and 100B are respectively shown in the direction of arrow B and the arrow shown in the figure. While rotating in the C direction, a metal strand 80 is supplied between the convex mold part 101 and the concave mold part 102 along the arrow A direction shown in the figure. As a result, the metal strand 80 is rolled into a substantially flat plate shape, and the shapes of the convex portion 101 and the concave portion 102 are transferred to the metal strand 80 and discharged along the direction of arrow D shown in the figure. The base 71a, the pair of protrusions 71b, and the groove 72 described above are formed in the metal wire 71.

  As shown in FIG. 7, when winding the metal wire 71, the tip of the metal wire 71 is fixed at a predetermined position of the core 200 having a columnar shape, and in this state, the core 200 is shown by an arrow shown in the drawing. The metal wire 71 is wound around the core member 200 while being supplied to the core member 200 along the direction of arrow E shown in the figure by rotating in the F direction. At this time, the metal wire 71 is obliquely moved with respect to the core material 200 by reciprocating the position of the metal wire 71 supplied to the core material 200 with respect to the axial direction of the core material 200 along the arrow G direction shown in the figure. Wrap around.

  At this time, the metal wire 71 is supplied to the core member 200 so that the wider main surface of the pair of main surfaces of the metal wire member 71 on which the groove portion 72 is formed faces the core member 200 side. Thereby, as for the metal wire 71 wound around the core material 200, the groove part 72 formed in the surface faces the core material 200 side. After the winding of the metal wire 71 around the core material 200 is completed, the metal wire 71 is cut and the core material 200 is extracted from the obtained wound body.

  The wound body thus manufactured is then subjected to a heat treatment for sintering, whereby the metal wires 71 are baked together. As described above, the filter 70A in the present embodiment is manufactured.

  The specific manufacturing method of the filter 70A described above is merely an example for obtaining the gas generator filter in the present embodiment, and can naturally be manufactured by other manufacturing methods.

(Embodiment 2)
FIG. 8 is a schematic perspective view of a gas generator filter according to Embodiment 2 of the present invention. Hereinafter, the gas generating filter in the present embodiment will be described with reference to FIG.

  As shown in FIG. 8, the filter 70B in the present embodiment forms a plain weave wire mesh by weaving using a plurality of the metal wire rods 71 (see FIG. 3) shown in the first embodiment. The formed plain woven wire mesh is laminated over a plurality of layers to form a hollow cylindrical braided body. Even in the filter 70B, the groove portion 72 provided on the surface of the metal wire 71 is configured to face the hollow portion 73 side of the filter 70B.

  Even when configured in this manner, the same effects as those described in the first embodiment can be obtained, and for a gas generator capable of obtaining a small size, light weight, high cooling performance and slag collection performance. It can be a filter.

(Modification)
FIG. 9 is a diagram showing the shape of the metal wire according to the first to fourth modifications. Hereinafter, with reference to this FIG. 9, the shape of the metal wire which concerns on a 1st thru | or 4th modification is demonstrated.

  In the filters 70A and 70B according to the first and second embodiments described above, as the metal wire 71 constituting the wound body or the braided body, a flat plate-like base portion 71a and a pair of flat plate-like shapes standing from both ends thereof are used. The case where the thing of the shape which has the protrusion part 71b was used was illustrated. However, instead of this, a metal wire having another shape may be used.

  For example, the metal wire 71A according to the first modification shown in FIG. 9A has a bent plate shape having a V-shaped cross-sectional view, whereby the groove 72 is formed on the metal wire. It is defined by the bent portion of 71A. Also in this case, the maximum outer dimension L1 of the metal wire 71A along the depth direction of the groove 72 is configured to be smaller than the maximum outer dimension L2 of the metal wire 71A along the width direction of the groove 72, and the groove 72 By constructing the wound body or the braided body so as to face the hollow portion side and manufacturing the filter, it is possible to obtain the same effects as those described in the first and second embodiments.

  Further, the metal wire 71B according to the second modification shown in FIG. 9B has a curved plate shape having a C-shape (more strictly speaking, approximately 1/3 arc shape) in sectional view. Thus, the groove 72 is defined by the curved portion of the metal wire 71B. Also in this case, the maximum outer dimension L1 of the metal wire 71B along the depth direction of the groove 72 is configured to be smaller than the maximum outer dimension L2 of the metal wire 71B along the width direction of the groove 72, and the groove 72 By constructing the wound body or the braided body so as to face the hollow portion side and manufacturing the filter, it is possible to obtain the same effects as those described in the first and second embodiments.

  Moreover, the metal wire 71C according to the third modified example shown in FIG. 9C has a curved plate shape having a corrugated cross-sectional shape, so that the pair of groove portions 72 are connected to the metal wire 71C. The two curved portions are respectively defined. Even in this case, the maximum outer dimension L1 of the metal wire 71C along the depth direction of the pair of grooves 72 is configured to be smaller than the maximum outer dimension L2 of the metal wire 71C along the width direction of the pair of grooves 72, and By manufacturing a filter by forming a wound body or a braided body so that the pair of groove portions 72 are directed toward the hollow portion, it is possible to obtain the same effects as those described in the first and second embodiments. it can.

  Furthermore, the metal wire 71D according to the fourth modification shown in FIG. 9D has a substantially flat plate shape, and has a V-shaped cross-sectional view on one of the wide main surfaces of the metal wire 71D. A groove 72 is formed. Also in this case, the maximum external dimension L1 of the metal wire 71D along the depth direction of the groove 72 is configured to be smaller than the maximum external dimension L2 of the metal wire 71D along the width direction of the groove 72, and the groove 72 By constructing the wound body or the braided body so as to face the hollow portion side and manufacturing the filter, it is possible to obtain the same effects as those described in the first and second embodiments.

  In the embodiments and modifications of the present invention described above, the case where the present invention is applied to a so-called disk-type gas generator and a filter for a gas generator provided therein has been described as an example. The invention is naturally applicable to a so-called cylinder type gas generator and a gas generator filter provided in the cylinder type gas generator. The cylinder type gas generator is preferably incorporated in, for example, a side airbag device, a curtain airbag device, or the like, and its outer shape is longer than that of a disk type gas generator. Therefore, the gas generator filter provided in the cylinder-type gas generator has a long cylindrical shape with a relatively small diameter.

  Here, when the present invention is applied to a cylinder-type gas generator and a filter for a gas generator provided in the cylinder-type gas generator, and the filter is constituted by a wound body of a metal wire, the axial direction of the filter In order to increase the strength of the wire, the metal wire that is wound in an oblique direction so as to intersect the circumferential direction and the axial direction of the filter is wound while being inclined so as to be more parallel to the axial direction. Is preferred.

  The above-described embodiments and modifications disclosed herein are illustrative in all respects and are not restrictive. The technical scope of the present invention is defined by the terms of the claims, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

  DESCRIPTION OF SYMBOLS 1 Gas generator, 10 Lower side shell, 11 Bottom plate part, 12 Perimeter wall part, 13 Projection cylinder part, 14 Depression part, 15 Opening part, 20 Upper side shell, 21 Top plate part, 22 Perimeter wall part, 23 Gas outlet , 24 Seal tape, 30 Holding portion, 31 Inner covering portion, 32 Outer covering portion, 33 Connecting portion, 34 Female connector portion, 40 Igniter, 41 Ignition portion, 42 Terminal pin, 50 Cup-shaped member, 51 Top wall portion , 52 Side wall portion, 53 Extension portion, 54 Tip portion, 55 Transfer chamber, 56 Transfer agent, 60 Combustion chamber, 61 Gas generating agent, 62 Lower holding member, 63 Upper holding member, 64 Cushion material, 70A, 70B Filter, 71, 71A to 71D Metal wire, 71a Base, 71b Projection, 72 Groove, 73 Hollow, 80 Metal strand, 100A, 100B Roll, 101 Convex Part, 102 concave part, 200 core material.

Claims (5)

A hollow cylindrical gas generator filter composed of a wound or braided body of metal wire,
The metal wire is made of a long member whose cross-sectional shapes at arbitrary positions in the extending direction of the metal wire match each other.
On the surface of the metal wire, a groove extending along the extending direction is provided,
The maximum outer dimension of the metal wire along the depth direction of the groove is smaller than the maximum outer dimension of the metal wire along the width direction of the groove,
The gas generator filter, wherein the groove portion faces the hollow portion side of the gas generator filter. The metal wire has a bent plate shape,
The gas generator filter according to claim 1, wherein the groove is defined by a bent portion of the metal wire. The metal wire has a curved plate shape,
The gas generator filter according to claim 1, wherein the groove is defined by a curved portion of the metal wire. The metal wire has a substantially flat plate shape,
The gas generator filter according to claim 1, wherein the groove is provided on one of the wide main surfaces of the metal wire.   The gas generator provided with the filter for gas generators in any one of Claim 1 to 4.

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