JP7085960B2 - Gas generator - Google Patents

Description

The present invention relates to a gas generator.

Conventionally, a gas generator used in an airbag device mounted on an automobile or the like is known. For example, Japanese Patent Application Laid-Open No. 2018-75985 (hereinafter referred to as “Patent Document 1”) describes a housing, a first igniter, an inner cylinder member, a first closing member, a second igniter, and a partition wall. And a gas generator comprising a second block member are disclosed. The first igniter is fixed to the bottom plate of the housing. The inner cylinder member houses the first igniter, and defines a fire transmission room around the first igniter. This firebox is filled with gunpowder. A second end opening is formed in the upper part of the inner cylinder member, and the second end opening is closed by the first closing member. The second igniter is fixed to a portion of the bottom plate of the housing separated from the first igniter. The partition wall divides the inside of the housing into a first combustion chamber provided on the top plate side of the housing and a second combustion chamber provided on the bottom plate side of the housing. The first combustion chamber is filled with the first gas generating agent, and the second combustion chamber is filled with the second gas generating agent. The partition wall is provided with a through hole through which the inner cylinder member is inserted, and the inner cylinder member is arranged so as to straddle the first combustion chamber and the second combustion chamber in a state of being inserted through the through hole. Therefore, the fire transmission chamber in the inner cylinder member communicates with the first combustion chamber through the second end opening. Further, the partition wall is provided with a second communication hole for communicating the first combustion chamber and the second combustion chamber, and the second communication hole is closed by a second closing member made of a metal adhesive tape or the like. ing.

In this gas generator, when the first igniter is ignited, the explosive charge filled in the inner cylinder member is burned. As a result, the first blocking member bursts, and the flame reaches the first combustion chamber through the second end opening and the through hole. Then, since the first gas generating agent burns, the gas generated by the combustion is ejected to the outside through the gas discharge port. This causes the airbag to inflate. At this time, the second closing member is maintained in a state in which the second communication hole is closed.

Subsequently, when the second igniter is ignited, the second gas generating agent burns in the second combustion chamber. Then, since the pressure in the second combustion chamber increases, the second closing member opens the second communication hole. Therefore, the gas generated by the combustion of the second gas generating agent is ejected to the outside through the second communication hole, the first combustion chamber, and the gas discharge port. This keeps the airbag inflated.

Japanese Unexamined Patent Publication No. 2018-75985

In the gas generator described in Patent Document 1, the flame generated during the combustion of the first gas generating agent is prevented from reaching from the first combustion chamber to the second combustion chamber, and the gas generated during the combustion of the second gas generating agent is prevented. A second communication hole is formed in the partition wall in order to allow the gas to flow out from the second combustion chamber to the first combustion chamber, and the second communication hole is closed by the second closing member. This structure is a complicated structure that requires a dedicated member for closing the communication hole, and the manufacturing process is also complicated.

An object of the present invention is to generate a flame during combustion of the first gas generating agent from the first combustion chamber to the second combustion chamber without using a dedicated member for closing the communication hole for communicating the first combustion chamber and the second combustion chamber. Providing a gas generator that can achieve both the prevention of the combustion of the second gas generating agent and the allowance of the gas generated during the combustion of the second combustion chamber to flow out from the second combustion chamber to the first combustion chamber. It is to be.

The gas generator according to the present invention is fixed to a housing having a lower wall and an upper wall facing each other, a first igniter having a first ignition unit, and the lower wall, and holds the first igniter. A first holder, a first fire chamber forming member provided around the first ignition chamber so as to define a first fire chamber around the first ignition unit, and the first fire chamber. The first igniter filled in the above, the second igniter having the second igniter, and the lower wall, which is fixed to a portion of the lower wall away from the first holder and holds the second igniter. A partition member for partitioning the two holders and a space inside the housing into a first combustion chamber facing the upper wall and a second combustion chamber facing the lower wall, and a first filling chamber filled with the first combustion chamber. It includes a gas generating agent and a second gas generating agent filled in the second combustion chamber. The housing is provided with a gas ejection hole that allows the first combustion chamber to communicate with the outside. The first fire chamber forming member includes a first siege cylinder that surrounds the first holder, a small cylinder portion having an outer shape smaller than the outer shape of the first siege cylinder, and the first siege cylinder and the small cylinder. It has a connecting portion that connects the portions. The partition member is provided with an insertion hole having a shape that allows the insertion of the small cylinder portion and prohibits the insertion of the connection portion. The first surrounding cylinder and the connecting portion are arranged in the second combustion chamber. The small cylinder portion is arranged in the first combustion chamber in a state of being inserted into the insertion hole. The partition member has a gap forming portion formed around the insertion hole. The partition member has a blocking posture in which the gap forming portion is in close contact with the connecting portion to block communication between the first combustion chamber and the second combustion chamber, and the gap forming portion is separated from the connecting portion. This makes it possible to deform between the gap forming posture that allows communication between the first combustion chamber and the second combustion chamber. The first firebox forming member opens the first firebox to the first combustion chamber when the first firebox is burned. The partition member takes the shutoff posture in response to the pressure increase in the first combustion chamber due to the combustion of the first gas generating agent, and the pressure increase in the second combustion chamber due to the combustion of the second gas generating agent. In response to this, the gap forming posture is taken.

In the gas generation based on the present invention, the partition member is provided in the second combustion chamber, and the deformation of the partition member toward the second combustion chamber during combustion of the first gas generating agent is restricted. It is preferable that the partition member is further provided with a support member for supporting the partition member.

In the gas generation based on the present invention, a second explosive may be further provided. In that case, the support member includes a support portion that is in contact with or in close proximity to the partition member, and is around the second ignition portion so as to define a second fire transmission chamber around the second ignition portion. The second extinguishing agent is filled in the second extinguishing chamber, and the support member is a flame generated by the combustion of the second extinguishing agent at the time of combustion of the second extinguishing agent. It is preferable to allow the second fire chamber to reach the second combustion chamber.

In the gas generation based on the present invention, the support member may further have a second surrounding cylinder surrounding the second holder. In that case, the support portion is connected to the second siege cylinder so as to close the opening of the second siege cylinder, and the second fire chamber is attached to the second siege cylinder. It is preferable that a through hole for communicating with the combustion chamber is provided.

In the gas generation based on the present invention, a filter provided in the first combustion chamber for cooling the gas generated by the combustion of the first gas generating agent and the second gas generating agent is a cylinder. The filter formed in a shape may be further provided. In that case, the partition member has a shape that surrounds the circumference of the first surrounding cylinder and the second surrounding cylinder when viewed along the direction connecting the lower wall and the upper wall. Moreover, it is preferable to have a filter support portion that supports the filter at a position overlapping the first surrounding cylinder and the second surrounding cylinder in a direction orthogonal to the direction.

In the gas generation based on the present invention, the partition member divides the space in the housing into the first combustion chamber and the second combustion chamber, and is provided with the insertion hole. It is preferable that the housing has a partition portion and an edge protruding portion protruding from the edge portion of the partition portion toward the second combustion chamber, and the housing has a receiving portion for receiving the edge protruding portion.

As described above, according to the present invention, the flame generated at the time of combustion of the first gas generating agent is first, without using a dedicated member for closing the communication hole connecting the first combustion chamber and the second combustion chamber. Achievement of both preventing the combustion chamber from reaching the second combustion chamber and allowing the gas generated during the combustion of the second gas generating agent to flow out from the second combustion chamber to the first combustion chamber. A possible gas generator can be provided.

It is sectional drawing of the gas generator of one Embodiment of this invention. It is sectional drawing which shows the state at the time of combustion of the 2nd gas generator of the gas generator shown in FIG.

Embodiments of the present invention will be described with reference to the drawings. In the drawings referred to below, the same or corresponding members are assigned the same number.

FIG. 1 is a cross-sectional view of a gas generator according to an embodiment of the present invention. As shown in FIG. 1, the gas generator 1 includes a housing 10, a first igniter 100, a first holder 110, a first fire chamber forming member 120, a first gunpowder 130, and a first. A gas generator 140, a second igniter 200, a second holder 210, a support member 220, a second explosive 230, a second gas generator 240, a partition member 300, a filter 400, and a cushion material. It includes 500 and a holding member 600.

The housing 10 has a combustion space for the first gas generating agent 140 and the second gas generating agent 240. The housing 10 has a lower shell 20 and an upper shell 30. The lower shell 20 and the upper shell 30 are made of a press-molded product formed by, for example, pressing a rolled metal plate-shaped member. As the metal plate-shaped member constituting the lower shell 20 and the upper shell 30, 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-tensile steel plate that does not break or break even when a tensile stress of [MPa] or less is applied is used.

The lower shell 20 has a lower wall 22 and a lower peripheral wall 24.
The lower wall 22 is formed in a flat plate shape. In the present embodiment, the lower wall 22 is formed in a disk shape. The lower wall 22 is provided with a first mounting hole 22a for mounting the first holder 110 and a second mounting hole 22b for mounting the second holder 210. The first mounting hole 22a is provided on one side of the center of the lower wall 22, and the second mounting hole 22b is provided on the other side of the center of the lower wall 22 (side of the first mounting hole 22a). There is.

The lower peripheral wall 24 is formed in a cylindrical shape and is connected to the lower wall 22. The lower peripheral wall 24 has a small diameter portion 25, a large diameter portion 26, and a receiving portion 27. The small diameter portion 25 has a shape that stands up from the outer edge portion of the lower wall 22. The large diameter portion 26 has a diameter larger than the diameter of the small diameter portion 25. The receiving portion 27 connects the small diameter portion 25 and the large diameter portion 26 so that the central axis of the small diameter portion 25 and the central axis of the large diameter portion 26 are aligned in a straight line. The receiving portion 27 has a shape in which the diameter gradually increases from the small diameter portion 25 toward the large diameter portion 26. The receiving portion 27 receives the partition member 300.

The upper shell 30 has an upper wall 32, an upper peripheral wall 34, and a flange 36.
The upper wall 32 is formed in a flat plate shape. In the present embodiment, the upper wall 32 is formed in a disk shape. The upper wall 32 faces the lower wall 22.

The upper peripheral wall 34 has a shape extending from the outer edge portion of the upper wall 32 toward the lower wall 22 side. The upper peripheral wall 34 is formed in a cylindrical shape. The inner diameter of the upper peripheral wall 34 is formed to be slightly smaller than the outer diameter of the large diameter portion 26. In other words, the large diameter portion 26 is press-fitted into the upper peripheral wall 34. The boundary between the upper peripheral wall 34 and the large diameter portion 26 is joined by welding or the like.

The upper peripheral wall 34 is provided with a gas ejection hole 34h for ejecting gas generated during combustion of the first gas generating agent 140 and the second gas generating agent 240 to the outside. The gas ejection hole 34h communicates the first combustion chamber S11, which will be described later, with the outside. The gas ejection hole 34h is closed by a metal sealing tape 35 as a sealing member. As the sealing tape 35, an aluminum foil or the like having an adhesive member coated on one side thereof can be preferably used, and the sealing tape 35 ensures the airtightness of the space inside the housing 10.

The flange 36 has a shape that projects outward from the outer peripheral surface of the upper peripheral wall 34 in the radial direction of the upper peripheral wall 34. The flange 36 is fixed to a retainer or the like provided in the airbag device.

The first igniter 100 is for generating a flame. The first igniter 100 has a first base 102, a first igniter 104, and a pair of first terminal pins 106.

The first ignition unit 104 is supported by the first base unit 102. The first ignition unit 104 has a squib cup, an igniter filled in the squib cup and burned by being ignited, and a resistor (bridge wire) for igniting the igniter. There is. Squib cups are generally made of metal or plastic. As the resistor, a nichrome wire or the like is generally used. As the igniter, ZPP (zirconium / potassium perchlorate), ZWPP (zirconium / tungsten / potassium perchlorate), lead styphnate and the like are generally used.

The pair of first terminal pins 106 are held by the first base 102 and are connected to the first ignition 104. Specifically, the pair of first terminal pins 106 are held by the first base 102 in a state where the ends of the pair of first terminal pins 106 are connected to the resistor in the squib cup.

The first holder 110 is fixed to the lower wall 22. Specifically, the first holder 110 is fixed to the lower wall 22 in a state of being inserted into the first mounting hole 22a. The boundary between the first holder 110 and the lower wall 22 is joined by welding or the like. The first holder 110 holds the first igniter 100. The first holder 110 is made of a metal material such as stainless steel, steel, aluminum alloy, and stainless alloy. The first holder 110 has a first base holding portion 112, a caulking portion 113, and a terminal pin surrounding portion 114.

The first base portion holding portion 112 is a portion that holds the first base portion 102. The first base holding portion 112 has a recess that can accept the first base 102. The caulking portion 113 crimps and fixes the first base portion 102 held by the first base portion holding portion 112. A sealing material (O-ring or the like) is provided between the first base holding portion 112 and the first base 102.

The terminal pin enclosing portion 114 has a shape that encloses the pair of first terminal pins 106. The terminal pin enclosing portion 114 is connected to the lower portion of the first base holding portion 112. The terminal pin surrounding portion 114 is inserted into the first mounting hole 22a. The terminal pin enclosing portion 114 has a shape that opens downward.

The first fire transmission room forming member 120 is provided around the first ignition unit 104 so as to define the first fire transmission room S10 around the first ignition unit 104. The first firebox forming member 120 has a first surrounding cylinder 122, a small cylinder portion 124, a connecting portion 126, and a closing portion 128.

The first enclosure 122 surrounds the first holder 110. The first siege cylinder 122 is formed in a cylindrical shape. The inner diameter of the first enclosure 122 is set to be slightly smaller than the outer diameter of the first holder 110. That is, the first holder 110 is press-fitted into the first surrounding cylinder 122. The lower end of the first enclosing cylinder 122 is in contact with the terminal pin enclosing portion 114. The first enclosing cylinder 122 has a shape that protrudes toward the upper wall 32 from the upper end portion of the first holder 110.

The small cylinder portion 124 has an outer shape smaller than the outer shape of the first surrounding cylinder 122. Specifically, the diameter of the small cylinder portion 124 is smaller than the diameter of the first surrounding cylinder 122. The small cylinder portion 124 has an opening that opens the first fire transmission chamber S10 to the first combustion chamber S11.

The connecting portion 126 connects the first surrounding cylinder 122 and the small cylinder portion 124. The outer surface of the connecting portion 126 is formed flat. The outer surface of the connecting portion 126 is parallel to the lower wall 22. The first enclosing cylinder 122, the small cylinder portion 124, and the connecting portion 126 have strengths that do not break during combustion of the first explosive charge 130 and the first gas generating agent 140. For example, the first surrounding cylinder 122, the small cylinder portion 124, and the connecting portion 126 are made of a metal material such as stainless steel, steel, or a stainless alloy.

The closing portion 128 has a shape that closes the opening of the small cylinder portion 124. The closing portion 128 is connected to the upper end portion of the small cylinder portion 124. The closing portion 128 is composed of a member that bursts or melts when the first explosive charge 130 is burned. For example, the closing portion 128 is a thin 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 the like). It is composed of a thin-film member made of a resin such as a thermoplastic resin typified by nylon 66), polypropylene sulfide resin, polypropylene oxide resin and the like.

The first explosive charge 130 is filled in the first extinguishing chamber S10. The first explosive charge 130 needs to be capable of reliably burning the first gas generating agent 140, and generally B / KNO ₃ , B / NaNO ₃ , and Sr (NO ₃ ). ) A composition composed of a metal powder / oxidizing agent typified by ₂ etc., a composition composed of titanium hydride / potassium perchlorate, a composition composed of B / 5-aminotetrazole / potassium nitrate / molybdenum trioxide, etc. are used. Be done. As the first explosive charge 130, a powdery one, one formed into a predetermined shape by a binder, or the like is used. The shape of the first explosive charge 130 formed by the binder includes various shapes such as a granule shape, a columnar shape, a sheet shape, a spherical shape, a single-hole cylindrical shape, a porous cylindrical shape, and a tablet shape. The first explosive charge 130 is ignited by the flame generated during the operation of the first igniter 100. Combustion of the first explosive 130 produces thermal particles. Since the closed portion 128 bursts or melts due to the combustion of the first combustion charge 130, the first transmission chamber S10 is opened to the first combustion chamber S11.

The second igniter 200 is for generating a flame. The configuration of the second igniter 200 is basically the same as the configuration of the first igniter 100. Therefore, the description of the second igniter 200 will be omitted. The second igniter 200 has a second base 202, a second igniter 204, and a pair of second terminal pins 206.

The second holder 210 is fixed to the lower wall 22. Specifically, the second holder 210 is fixed to the lower wall 22 in a state of being inserted into the second mounting hole 22b. The boundary between the second holder 210 and the lower wall 22 is joined by welding or the like. The configuration of the second holder 210 is basically the same as the configuration of the first holder 110. Therefore, the description of the second holder 210 will be omitted. That is, the second holder 210 has a second base portion holding portion 212, a caulking portion 213, and a terminal pin surrounding portion 214.

The partition member 300 partitions the space inside the housing 10 into a first combustion chamber S11 facing the upper wall 32 and a second combustion chamber S21 facing the lower wall 22. The first combustion chamber S11 is filled with the first gas generating agent 140, and the second combustion chamber S21 is filled with the second gas generating agent 240. The first gas generating agent 140 and the second gas generating agent 240 will be described later. The partition member 300 is made of a metal material such as stainless steel, steel, aluminum alloy, and stainless alloy. The partition member 300 has a partition portion 310, an upright cylinder portion 320, and an edge portion protruding portion 330. The partition member 300 can be formed by press molding.

The partition portion 310 partitions the space inside the housing 10 into a first combustion chamber S11 and a second combustion chamber S21. The partition portion 310 has a flat plate portion 312 and a filter support portion 314.

The flat plate portion 312 is formed in a flat plate shape. The flat plate portion 312 is provided with an insertion hole 312h. The insertion hole 312h has a shape that allows the insertion of the small cylinder portion 124 and prohibits the insertion of the connecting portion 126. The insertion hole 312h is formed in a circular shape. The diameter of the insertion hole 312h is larger than the outer diameter of the small cylinder portion 124 and smaller than the outer diameter of the connecting portion 126 (first surrounding cylinder 122). The small cylinder portion 124 is arranged in the first combustion chamber S11 in a state of being inserted into the insertion hole 312h. The first surrounding cylinder 122 and the connecting portion 126 are arranged in the second combustion chamber S21.

The flat plate portion 312 has a gap forming portion 313 formed around the insertion hole 312h. The gap forming portion 313 is provided at a position of the flat plate portion 312 that overlaps with the connecting portion 126 in the direction connecting the lower wall 22 and the upper wall 32. The gap forming portion 313 may be in contact with the connecting portion 126 or slightly separated from the connecting portion 126 before the combustion of the first gas generating agent 140.

The partition member 300 is deformable between a blocking posture and a gap forming posture (the posture shown in FIG. 2). FIG. 2 is a cross-sectional view showing a state of the second gas generator of the gas generator shown in FIG. 1 at the time of combustion.

The shutoff posture is a posture in which the gap forming portion 313 is in close contact with the connecting portion 126 to block the communication between the first combustion chamber S11 and the second combustion chamber S21. More specifically, in the shutoff posture, the gap forming portion 313 is in close contact with the connecting portion 126, so that the flame generated by the combustion of the first gas generating agent 140 reaches from the first combustion chamber S11 to the second combustion chamber S21. It is a posture to block.

The gap forming posture is a posture that allows communication between the first combustion chamber S11 and the second combustion chamber S21 by separating the gap forming portion 313 from the connecting portion 126. More specifically, in the gap forming posture, the gap forming portion 313 is separated from the connecting portion 126, so that the gas generated by the combustion of the second gas generating agent 240 is transferred from the second combustion chamber S21 to the first combustion chamber S11. This is a posture in which a gap G (see FIG. 2) that allows inflow is formed between the gap forming portion 313 and the connecting portion 126.

The filter support portion 314 will be described later.
The upright cylinder portion 320 has a shape of standing up toward the upper wall 32 from a portion of the flat plate portion 312 around the insertion hole 312h. The upright tubular portion 320 is formed in a cylindrical shape. The length of the upright cylinder portion 320 in the axial direction of the upright cylinder portion 320 is smaller than the length of the small cylinder portion 124 in the axial direction of the small cylinder portion 124. The standing cylinder portion 320 may be omitted.

The edge protruding portion 330 has a shape that protrudes from the edge of the partition portion 310 toward the second combustion chamber S21 side (lower wall 22 side). The edge protrusion 330 is formed in a cylindrical shape. The outer diameter of the edge protruding portion 330 is set to be substantially equal to the inner diameter of the large diameter portion 26. The edge protruding portion 330 is received by the receiving portion 27 of the lower peripheral wall 24.

Here, the first gas generating agent 140 and the second gas generating agent 240 will be described. As the first gas generating agent 140 and the second gas generating agent 240, it is preferable to use a non-azidated gas generating agent, and generally, these first gas generating agents 140 and these first gas generating agents 140 and as a molded body containing a fuel, an oxidizing agent and an additive are used. The second gas generating agent 240 is formed.

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.

As the oxidizing agent, for example, a basic nitrate such as basic copper nitrate, a perchlorate such as ammonium perchlorate and potassium perchlorate, an alkali metal, an alkaline earth metal, a transition metal, and a cation selected from ammonia. Nitrate and the like containing the above are used. As the nitrate, for example, sodium nitrate, potassium nitrate and the like are preferably used.

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 polyvinyl alcohol, a metal salt of carboxymethyl cellulose and a stearate, and an inorganic binder such as synthetic hydrotalcite and acidic clay can be preferably used. In addition, as binders, polysaccharide derivatives such as hydroxyethyl cellulose, hydroxypropylmethyl cellulose, cellulose acetate, propionate cellulose, butyrate acetate cellulose, nitrocellulose, microcrystalline cellulose, guagam, polyvinylpyrrolidone, polyacrylamide, and starch Further, inorganic binders such as molybdenum disulfide, starch, bentonite, silica soil, kaolin and alumina can also be preferably used. As the slag forming agent, silicon nitride, silica, acidic white clay and the like can be preferably used. As the combustion regulator, metal oxides, ferrosilicon, activated carbon, graphite and the like can be preferably used.

The shape of the molded body of the gas generating agent includes various shapes such as granular ones such as granules, pellets, and cylinders, and discs. Further, in the case of a columnar type, a perforated (for example, single-hole cylinder shape, perforated cylinder shape, etc.) molded body 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 device into which the gas generator 1 is incorporated. For example, a shape in which the gas generation rate changes with time during combustion of the gas generator is selected. It is preferable to select the optimum shape according to the specifications. In addition to the shape of the gas generating agent, it is preferable to appropriately select the size and filling amount of the molded product in consideration of the linear combustion rate of the gas generating agent, the pressure index, and the like.

The first gas generating agent 140 and the second gas generating agent 240 may have the same composition or may have different compositions. Further, the first gas generating agent 140 and the second gas generating agent 240 may have the same shape and size, or may be different from each other.

The support member 220 is provided in the second combustion chamber S21. The support member 220 supports the partition member 300 so as to restrict the deformation of the partition member 300 toward the second combustion chamber S21 during combustion of the first gas generating agent 140. In the present embodiment, the support member 220 has a shape that surrounds the second ignition unit 204 so as to define the second fire transmission room S20 around the second ignition unit 204. That is, the support member 220 also has a function as a second fire transmission room forming member. Specifically, the support member 220 has a second surrounding cylinder 222 and a support portion 224. The support member 220 has a strength that does not break when the second explosive 230 is burned. The support member 220 is made of a metal material such as stainless steel, steel, aluminum alloy, or stainless alloy.

The second enclosure 222 surrounds the second holder 210. The second siege cylinder 222 is formed in a cylindrical shape. The inner diameter of the second enclosure 222 is set to be slightly smaller than the outer diameter of the second holder 210. That is, the second holder 210 is press-fitted into the second surrounding cylinder 222. The lower end of the second enclosure 222 is in contact with the lower wall 22. The second surrounding cylinder 222 has an upper cylinder portion 223 located on the upper wall 32 side of the upper end portion of the second holder 210.

The upper cylinder portion 223 is provided with a through hole 223h for communicating the second fire transmission chamber S20 with the second combustion chamber S21. Through holes 223h are provided at a plurality of locations arranged along the circumferential direction of the upper cylinder portion 223. The through hole 223h is set to a size that prevents the second explosive charge 230 from flowing out of the second extinguishing chamber S20. However, as the second explosive agent 230, one having a particle size capable of passing through the through hole 223h may be used. In this case, a thin-film member made of sealing tape or the like so as to close the through hole 223h, and the member that opens the second combustion chamber S20 to the second combustion chamber S21 when the second combustion charge 230 is burned. , May be provided on the upper cylinder portion 223 of the second surrounding cylinder 222.

The support portion 224 is formed in a disk shape and is connected to the upper end portion of the upper cylinder portion 223. The support portion 224 is arranged at a position in contact with or close to the flat plate portion 312 of the partition member 300. A through hole 223h may be provided in the support portion 224.

The second power transmission agent 230 is filled in the second fire transmission room S20. The second explosive agent 230 needs to be capable of reliably burning the second gas generating agent 240, and like the first explosive agent 130, a boron-based ignition agent or the like is preferably used. However, as the second explosive agent 230, one having the same composition as the second gas generating agent 240 may be used. The second explosive 230 is ignited by the flame generated during the operation of the second igniter 200. Combustion of the second explosive 230 produces thermal particles.

The filter 400 is provided in the first combustion chamber S11. The filter 400 cools the gas generated by the combustion of the first gas generating agent 140 and the second gas generating agent 240. The filter 400 also has a function of removing residues (slag) and the like contained in the gas. The filter 400 has a size capable of enclosing the first enclosing cylinder 122 and the second enclosing cylinder 222 together. Specifically, the filter 400 is formed in a cylindrical shape. As the filter 400, a filter 400 obtained by winding and sintering a metal wire such as stainless steel or steel, or a filter 400 formed by knitting a metal wire and compacted by pressing is preferably used.

Here, the filter support portion 314 will be described. The filter support portion 314 is a portion that supports the filter 400 and is connected to the edge portion of the flat plate portion 312. The filter support portion 314 has a shape that surrounds the periphery of the first siege cylinder 122 and the second siege cylinder 222 over the entire area when viewed along the direction connecting the lower wall 22 and the upper wall 32. The filter support portion 314 supports the filter 400 at a position overlapping the first siege cylinder 122 and the second siege cylinder 222 in a direction orthogonal to the direction connecting the lower wall 22 and the upper wall 32. Specifically, the upper surface of the filter support portion 314 is in contact with the lower surface 410 of the filter 400, and the outer peripheral surface of the filter support portion 314 is in contact with the lower portion 430 of the inner peripheral surface of the filter 400. The upper surface 420 of the filter 400 is in contact with the inner surface of the upper wall 32.

The cushion material 500 is a member that suppresses pulverization of the first gas generating agent 140 due to vibration or the like of the housing 10. The cushion material 500 is arranged between the first gas generating agent 140 and the upper wall 32. The cushion material 500 is preferably composed of a ceramic fiber molded body, rock wool, a foamed resin (foamed silicone, foamed polyprene, foamed polyethylene, etc.), chloroprene, and a member made of rubber typified by EPDM. The cushion material 500 is formed in a disk shape or a columnar shape. The cushion material 500 is burnt down by the combustion of the first gas generating agent 140.

The holding member 600 is a member that holds the cushion material 500 inside the filter 400. In the holding member 600, the gas generated by the combustion of the first gas generating agent 140 and the second gas generating agent 240 flows out of the filter 400 through the gap between the filter 400 and the upper wall 32 without passing through the filter 400. Suppress. Specifically, the holding member 600 has a disk portion 610 and a cylindrical portion 620. The disk portion 610 is formed in a disk shape and is arranged between the upper surface of the cushion material 500 and the inner surface of the upper wall 32. The cylindrical portion 620 has a shape extending from the outer edge portion of the disk portion 610 toward the lower wall 22, and is arranged between the outer peripheral surface of the cushion material 500 and the inner peripheral surface of the filter 400. The holding member 600 is formed by, for example, pressing a metal plate-shaped member such as stainless steel, steel, an aluminum alloy, or a stainless alloy.

Next, the operation of the gas generator 1 will be described.
When a vehicle on which the gas generator 1 is mounted collides, first, an ignition signal is transmitted from the control unit mounted on the vehicle to the first igniter 100 to operate the first igniter 100. Specifically, the igniter filled in the first ignition unit 104 is ignited by being heated by the resistor, and the squib cup of the first ignition unit 104 bursts when the igniter burns. As a result, the first explosive charge 130 filled in the first cup member 140 burns. As a result, the closed portion 128 bursts or melts, and the first fire transmission chamber S10 is opened to the first combustion chamber S11.

Then, since the first gas generating agent 140 in the first combustion chamber S11 burns, the gas generated by the combustion is ejected to the outside of the housing 10 through the filter 400 and the gas ejection hole 34h. At this time, the gas is cooled by the filter 400, and the slag contained in the gas is removed by the filter 400. While the first gas generating agent 140 is burning, the pressure in the first combustion chamber S11 rises, so that an external force acts on the partition member 300 in the direction from the first combustion chamber S11 to the second combustion chamber S21. Therefore, the partition member 300 is in the blocking posture. Therefore, the flame generated by the combustion of the first gas generating agent 140 is prevented from reaching the first combustion chamber S11 to the second combustion chamber S21.

Due to the combustion of the first gas generating agent 140, the cushion material 500 is burnt down, and the upper wall 32 and the disk portion 610 are deformed into a shape that bulges outward.

After that, when the second igniter 200 is ignited, the second combustion charge 230 burns, and the flame generated by this combustion reaches from the second transmission chamber S20 to the second combustion chamber S21 through the through hole 223h. Then, the second gas generating agent 240 in the second combustion chamber S21 burns, so that the pressure in the second combustion chamber S21 rises. As a result, an external force acts on the partition member 300 in the direction from the second combustion chamber S21 to the first combustion chamber S11, so that the partition member 300 is deformed into the gap forming posture (posture shown in FIG. 2). Therefore, the gas generated by the combustion of the second gas generating agent 240 flows into the first combustion chamber S11 through the gap G between the gap forming portion 313 and the connecting portion 126.

As described above, in the present gas generator 1, the flame generated at the time of combustion of the first gas generating agent 140 is generated without using a dedicated member for closing the communication hole for communicating the first combustion chamber S11 and the second combustion chamber S21. It prevents the first combustion chamber S11 from reaching the second combustion chamber S21, and allows the gas generated during the combustion of the second gas generating agent 240 to flow out from the second combustion chamber S21 to the first combustion chamber S11. It is possible to achieve both that and that.

Further, since the gas generator 1 includes the support member 220, deformation or displacement of the partition member 300 during combustion of the first gas generator 140 is suppressed.

Further, the support member 220 defines a second firebox S20 around the second ignition unit 204, and the second firebox S20 is filled with the second firebox 230, so that the first combustion is performed. In addition to suppressing deformation of the partition member 300 during combustion of the first gas generating agent 140 in the chamber S11, a stable combustion state of the second gas generating agent 240 is also ensured.

Further, since the partition member 300 has the filter support portion 314, it is possible to secure a large volume of the filter 400.

Further, since the partition member 300 has an edge protruding portion 330 and the housing 10 has a receiving portion 27, the first gas generating agent 140 is burned in the first combustion chamber S11 (partition). Displacement of the partition member 300 in the action of an external force in the direction from the first combustion chamber S11 to the second combustion chamber S21 with respect to the member 300 is suppressed.

The first igniter 100 and the second igniter 200 may be ignited at the same time. In this case, due to the pressure difference between the first combustion chamber S11 and the second combustion chamber S21, the first external force in the direction from the first combustion chamber S11 to the second combustion chamber S21 with respect to the partition member 300 is larger. While the partition member 300 is in a blocking posture while being larger than the second external force in the direction from the second combustion chamber S21 to the first combustion chamber S11 with respect to the partition member 300, the partition member 300 is in a shut-off posture, and conversely, the second external force is larger than the first external force. While it is large, the partition member 300 is in a gap forming posture.

Further, in the above embodiment, if the support member 220 supports the partition member 300 so as to restrict the deformation of the partition member 300 toward the second combustion chamber S21 during combustion of the first gas generating agent 140, if the support member 220 supports the partition member 300. The shape is not limited to the shape that defines the second fire transmission room S20. For example, the support member 220 may be composed of a columnar member provided between the lower wall 22 and the partition member 300, or between the second holder 210 and the partition member 300. In this case, the second gas generating agent 240 is filled in place of the second explosive 230.

Alternatively, in the above embodiment, the support member 220 may be omitted. Also in this case, the second gas generating agent 240 is filled in place of the second explosive agent 230.

Further, in the above embodiment, the first igniter 100 and the second igniter 200 are configured to be assembled to the lower wall 22 of the housing 10 via the first metal holder 110 and the second holder 210, respectively. Although examples are shown, both the first igniter 100 and the second igniter 200 may be configured to be assembled to the lower wall 22 by so-called insert molding. In that case, the gas generator 1 has a first holding portion and a second holding portion made of a resin molded portion in place of the first holder 110 and the second holder 210 described above, and is a first igniter. The 100 and the second igniter 200 will be assembled to the lower wall 22 via the first holding portion and the second holding portion, respectively.

Specifically, the first holding portion and the second holding portion are formed by injection molding using a mold. As a raw material for the first holding portion and the second holding portion 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, it is not limited to the thermocurable resin typified by epoxy resin or the like, but is typified by polybutylene terephthalate resin, polyethylene terephthalate resin, polyamide resin (for example, nylon 6 or nylon 66), polypropylene sulfide resin, 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 first holding portion and the second holding portion 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.

It should be noted that the embodiments disclosed this time are examples in all respects and should be considered not to be restrictive. The scope of the present invention is shown by the scope of claims rather than the description of the embodiment described above, and further includes all modifications within the meaning and scope equivalent to the scope of claims.

1 gas generator, 10 housing, 20 lower shell, 22 lower wall, 22a first mounting hole, 22b second mounting hole, 24 lower peripheral wall, 25 small diameter part, 26 large diameter part, 27 receiving part, 30 upper shell , 32 upper wall, 34 upper peripheral wall, 34h gas ejection hole, 36 flange, 100 1st igniter, 102 1st base, 104 1st igniter, 106 1st terminal pin, 110 1st holder, 112 1st base holding Part, 113 caulking part, 114 terminal pin siege part, 120 first fire chamber forming member, 122 first siege cylinder, 124 small cylinder part, 126 connecting part, 128 obstruction part, 130 first igniter, 140 first gas Generator, 200 2nd igniter, 202 2nd base, 204 2nd igniter, 206 2nd terminal pin, 210 2nd holder, 212 2nd base holding part, 213 caulking part, 214 terminal pin surrounding part, 220 support Member, 222 2nd encircling cylinder, 223 upper cylinder part, 223h through hole, 224 support part, 230 2nd combustion charge, 240 2nd gas generating agent, 300 partition member, 310 partition part, 312 flat plate part, 312h insertion hole, 313 Gap forming part, 314 Filter support part, 320 Standing cylinder part, 330 Edge part protruding part, 400 filter, 500 Cushion material, 600 Holding member, S10 1st fire chamber, S11 1st combustion chamber, S20 2nd fire Chamber, S21 second combustion chamber.

Claims (6)

A housing with lower and upper walls facing each other,
A first igniter having a first igniter and
A first holder fixed to the lower wall and holding the first igniter,
A first fire chamber forming member provided around the first ignition unit so as to define a first fire chamber around the first ignition unit.
The first explosive filled in the first extinguishing chamber and
A second igniter having a second igniter and
A second holder fixed to a portion of the lower wall separated from the first holder and holding the second igniter, and a second holder.
A partition member that partitions the space inside the housing into a first combustion chamber facing the upper wall and a second combustion chamber facing the lower wall.
The first gas generating agent filled in the first combustion chamber and
A second gas generating agent filled in the second combustion chamber is provided.
The housing is provided with a gas ejection hole that allows the first combustion chamber to communicate with the outside.
The first fire chamber forming member is
The first siege cylinder that surrounds the first holder,
A small cylinder portion having an outer shape smaller than the outer shape of the first surrounding cylinder,
It has a connecting portion for connecting the first surrounding cylinder and the small cylinder portion, and has.
The partition member is provided with an insertion hole having a shape that allows the insertion of the small cylinder portion and prohibits the insertion of the connection portion.
The first surrounding cylinder and the connecting portion are arranged in the second combustion chamber.
The small cylinder portion is arranged in the first combustion chamber in a state of being inserted into the insertion hole.
The partition member has a gap forming portion formed around the insertion hole.
The partition member has a blocking posture in which the gap forming portion is in close contact with the connecting portion to block communication between the first combustion chamber and the second combustion chamber, and the gap forming portion is separated from the connecting portion. As a result, it is possible to deform between the gap forming posture that allows communication between the first combustion chamber and the second combustion chamber.
The first firebox forming member opens the first firebox to the first combustion chamber when the first firebox is burned.
The partition member takes the shutoff posture in response to the pressure increase in the first combustion chamber due to the combustion of the first gas generating agent, and the pressure increase in the second combustion chamber due to the combustion of the second gas generating agent. A gas generator that takes the gap forming posture in response to the above. A support member provided in the second combustion chamber and supporting the partition member so as to restrict deformation of the partition member toward the second combustion chamber during combustion of the first gas generator is further provided. , The gas generator according to claim 1. With more gunpowder
The support member includes a support portion that is in contact with or is in close proximity to the partition member, and has a shape that surrounds the circumference of the second ignition portion so as to define a second fire transmission room around the second ignition portion. death,
The second extinguishing agent is filled in the second extinguishing room.
The support member according to claim 2, wherein the support member allows the flame generated by the combustion of the second combustion charge to reach from the second transmission chamber to the second combustion chamber at the time of combustion of the second transmission charge. Gas generator. The support member further comprises a second enclosure that surrounds the second holder.
The support portion is connected to the second siege cylinder so as to close the opening of the second siege cylinder.
The gas generator according to claim 3, wherein the second enclosure is provided with a through hole for communicating the second fire chamber to the second combustion chamber. A filter provided in the first combustion chamber for cooling the gas generated by the combustion of the first gas generator and the second gas generator, further comprising the filter formed in a cylindrical shape.
The partition member has a shape that surrounds the periphery of the first surrounding cylinder and the second surrounding cylinder when viewed along the direction connecting the lower wall and the upper wall, and has a shape that surrounds the entire circumference and the direction. The gas generator according to claim 4, further comprising a filter support portion that supports the filter at a position overlapping the first siege cylinder and the second siege cylinder in an orthogonal direction. The partition member is
The space in the housing is divided into the first combustion chamber and the second combustion chamber, and the partition portion provided with the insertion hole and the partition portion.
It has an edge protruding portion protruding from the edge portion of the partition portion toward the second combustion chamber side.
The gas generator according to any one of claims 1 to 5, wherein the housing has a receiving portion for receiving the edge protrusion.

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