Gas generator

Abstract

To provide a technique capable of simplifying the structure of a gas generator using fuel gas and oxidative gas.SOLUTION: A gas generator comprises: a first partition wall part which defines, within an outer-shell housing, an ignition chamber with ignition means accommodated therein and a gas filling chamber filled with gas; a first communication part which is provided in the first partition wall part, and which is opened by actuation of an igniter, thereby allowing the ignition chamber to communicatee with the gas filling chamber; a discharge part which is provided in the outer-shell housing, and which is opened by actuation of the igniter, thereby allowing the gas filling chamber to communicate with the outside of the outer-shell housing; a second partition wall part which defines, within the gas-filling chamber, a first filling chamber adjacent to the first communication part and a second filling chamber adjacent to the discharge part; fuel gas filled into one of the first filling chamber and the second filling chamber; oxidative gas filled into the other of the first filling chamber and the second filling chamber; and a second communication part which is provided in the second partition wall part, and which is opened by actuation of the igniter, thereby allowing the first filling chamber to communicate with the second filling chamber.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a gas generator. [Background technology]

[0002] Conventionally, gas generators that accommodate a gas source in an accommodation space formed in a housing and discharge gas to the outside by activating an igniter are widely known. This type of gas generator is used, for example, to supply gas to an airbag or a seat belt retractor. In this connection, an airbag inflator has been disclosed (for example, Patent Document 1) that generates a combustion gas (water vapor, etc.) by igniting a mixed gas of an oxidizable gas (fuel gas) such as hydrogen gas and an oxidizing gas such as oxygen gas, and inflates the airbag by supplying the combustion gas to the airbag as a working gas. In the airbag inflator of Patent Document 1, a bottle containing an oxidizable gas and a bottle containing an oxidizing gas are connected to a common chamber, and a sealing foil that blocks the outlet of each bottle is ruptured by ignition of a squib, so that the gas in each bottle is discharged into the chamber, and the mixed gas is ignited. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] US Patent Application Publication No. 2010 / 0283231 [Patent Document 2] U.S. Pat. No. 5,582,806 [Patent Document 3] Japanese Patent Application Publication No. 9-20203 Summary of the Invention [Problem to be solved by the invention]

[0004] An object of the technology disclosed herein is to enable a simplification of the structure of a gas generator that uses a fuel gas and an oxidizing gas. [Means for solving the problem]

[0005] (Aspect 1) In order to solve the above problems, a gas generator according to one aspect of the present disclosure employs the following configuration. That is, the gas generator according to the present disclosure comprises: An outer housing; an ignition means including an igniter that is actuated to release combustion products; a first partition wall portion defining an ignition chamber in which the ignition means is housed and a gas-filled chamber in which gas is filled inside the outer shell housing; a first communication portion provided in the first partition portion, the first communication portion being closed before the igniter is activated and opening upon activation of the igniter to communicate between the ignition chamber and the gas-filled chamber; a discharge portion provided in the outer shell housing, the discharge portion being closed before the igniter is activated and being opened by the activation of the igniter to communicate the gas filling chamber with the outside of the outer shell housing; a second partition wall portion defining a first filled chamber adjacent to the first communication portion and a second filled chamber adjacent to the discharge portion inside the gas filled chamber; A fuel gas filled in one of the first filling chamber and the second filling chamber; an oxidizing gas filled in the other of the first filling chamber and the second filling chamber; The second communication portion is provided in the second partition portion, is closed before the igniter is activated, and opens upon activation of the igniter, thereby communicating the first filling chamber with the second filling chamber.

[0006] (Aspect 2) In the above first aspect, the igniter and the first communication portion may be disposed opposite to each other.

[0007] (Aspect 3) In the above-mentioned first or second aspect, the first communication portion and the second communication portion may be disposed opposite to each other.

[0008] (Aspect 4) In any one of the above aspects 1 to 3, the second communication portion and the discharge portion may be disposed opposite to each other.

[0009] (Aspect 5) In any one of the above aspects 1 to 4, the igniter, the first communication portion, the second communication portion, and the discharge portion may be arranged on the same straight line.

[0010] (Aspect 6) In any one of the above aspects 1 to 5, the outer shell housing is formed into a bottomed cylindrical shape, The igniter, the first communication portion, the second communication portion, and the exhaust portion may be disposed on a central axis of the outer shell housing.

[0011] (Aspect 7) The gas generator according to any one of the first to sixth aspects further comprises a cylindrical diffuser housing having one end joined to the outer shell housing so as to form therein a diffusion chamber that is in communication with the gas-filled chamber via the exhaust portion, A gas exhaust hole communicating the diffusion chamber with the outside of the gas generator may be formed in a peripheral wall portion of the diffuser housing.

[0012] (Aspect 8) In any one of the above-mentioned aspects 1 to 7, the fuel gas may be filled into one of the first filling chamber and the second filling chamber together with an inert gas.

[0013] (Aspect 9) In any of the above aspects 1 to 8, the fuel gas may be hydrogen gas.

[0014] (Aspect 10) In the above-mentioned ninth aspect, the wall surface of either the first filling chamber or the second filling chamber which is filled with the hydrogen gas may be coated with a hydrogen embrittlement resistant film.

[0015] (Aspect 11) In any one of the above aspects 1 to 10, the oxidizing gas may be filled in the other of the first and second filling chambers together with an inert gas.

[0016] (Aspect 12) In any of the above aspects 1 to 11, the second communication portion may be formed as part of the second partition portion so as to be ruptured by activation of the igniter, and may protrude in a dome shape toward the second filling chamber.

[0017] (Aspect 13) In the twelfth aspect above, the second communication portion may be formed to be thinner than other portions of the second partition portion.

[0018] (Aspect 14) In the above-mentioned twelfth or thirteenth aspect, the second communicating portion may have a linear weakened portion formed to be thinner than other portions of the second communicating portion.

[0019] (Aspect 15) In any one of the above-mentioned aspects 1 to 14, the ignition means may include a gas generating agent that is disposed in the ignition chamber and that is combusted by the activation of the igniter.

[0020] (Aspect 16) In any of the above-mentioned aspects 1 to 15, the first communication portion may be formed by an opening formed in the first partition portion, and a rupture disc that closes the opening before activation of the igniter and that ruptures when the igniter is activated.

[0021] (Aspect 17) In any of the above-mentioned aspects 1 to 5, the discharge portion may be formed by an opening formed in the outer shell housing, and a rupture disk that closes the opening before activation of the igniter and that ruptures when the igniter is activated.

[0022] (Aspect 18) In any one of the above-mentioned aspects 1 to 17, the outer shell housing is formed into a bottomed cylindrical shape, The first filling chamber has a first axial region adjacent to the ignition chamber in the axial direction of the outer shell housing across the first partition wall, and a cylindrical first radial region surrounding the ignition chamber from the radial direction of the outer shell housing across the first partition wall, The second filling chamber may have a second axial region adjacent to the first axial region of the first filling chamber in the axial direction of the outer shell housing, sandwiching the second partition portion, and a cylindrical second radial region surrounding the first radial region of the first filling chamber from the radial direction of the outer shell housing, sandwiching the second partition portion.

[0023] (Aspect 19) The gas generator according to any one of the first to eighteenth aspects above further comprises a cylindrical diffuser housing, one end of which is joined to the outer shell housing so as to form therein a diffusion chamber that is in communication with the gas-filled chamber via the exhaust portion, a gas exhaust hole communicating the diffusion chamber with the outside of the gas generator is formed in a peripheral wall portion of the diffuser housing, The diffusion chamber is adjacent to the gas-filled chamber in the axial direction of the outer shell housing, with a wall of the outer shell housing in between, A gas generator housing formed by the outer shell housing and the diffuser housing may have an axial length that is shorter than its radial width. Effect of the Invention

[0024] According to the technique of the present disclosure, it is possible to simplify the structure of a gas generator using a fuel gas and an oxidizing gas. [Brief description of the drawings]

[0025] [Figure 1] FIG. 1 is a cross-sectional view showing a state before activation of a gas generator according to an embodiment. [Diagram 2] FIG. 2 is a view for explaining a second communication portion according to the embodiment. [Diagram 3] FIG. 3 is a view for explaining a modified example of the second communication portion. [Figure 4]FIG. 4 is a cross-sectional view showing a state in which the gas generator according to the embodiment is in operation. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0026] Hereinafter, an embodiment of the present disclosure will be described with reference to the drawings. In the embodiment described below, an aspect in which the technology according to the present disclosure is applied to a gas generator (inflator) for an airbag will be described. However, the use of the technology according to the present disclosure is not limited thereto, and it may be applied to a gas generator for a seat belt retractor, for example. Note that each configuration and their combinations in each embodiment are merely examples, and addition, omission, substitution, and other modifications of the configurations are possible as appropriate within the scope of the gist of the present invention. The present disclosure is not limited by the embodiments, but is limited only by the claims.

[0027] [Overall configuration] Fig. 1 is a cross-sectional view showing a state before activation of a gas generator 100 according to an embodiment. Fig. 1 shows a cross section along the axial direction of an outer shell housing indicated by reference numeral 10. The gas generator 100 is an airbag inflator, and is a device that supplies an activation gas to an airbag (not shown) for inflating the airbag upon activation. The gas generator 100 is configured to generate water vapor, which is a combustion gas, by igniting a mixed gas of hydrogen gas, which is an example of a fuel gas, and oxygen gas, which is an example of an oxidizing gas, and to supply the water vapor to the airbag as a gas for activating the airbag (hereinafter, "activation gas").

[0028] As shown in FIG. 1, the gas generator 100 includes an upper shell 1, a lower shell 2, an intermediate shell 3, an ignition means 20, a holding member 5, a first rupture disc 6, a second rupture disc 7, a diffuser housing 8, and a filter 9, and is formed into a bottomed tubular shape with both ends closed. Although details will be described later, an outer shell housing 10 shown by a dot pattern in FIG. 1 is formed by a part of the upper shell 1 and the lower shell 2 and a part of the intermediate shell 3. The outer shell housing 10 is formed into a bottomed tubular shape with both ends closed. Symbol A1 in FIG. 1 indicates the central axis of the outer shell housing 10. Hereinafter, the direction along the axial direction of the outer shell housing 10 is defined as the up-down direction of the gas generator 100, the lower shell 2 side (i.e., the lower side in FIG. 1) is the lower side of the gas generator 100, and the opposite side (i.e., the upper side of the upper shell 1 in FIG. 1) is the upper side of the gas generator 100. Furthermore, in the following description, unless otherwise specified, "axial direction" refers to the axial direction of outer shell housing 10, "radial direction" refers to the radial direction of outer shell housing 10, and "circumferential direction" refers to the circumferential direction of outer shell housing 10. Each component of gas generator 100 will be described below.

[0029] [Upper shell, lower shell, middle shell] The upper shell 1 has an upper outer peripheral wall portion 11, a top plate portion 12, an upper inner peripheral wall portion 13, and a flange portion 15, and is formed in a bottomed cylindrical shape with a closed upper end. The upper outer peripheral wall portion 11 is formed in a cylindrical shape extending vertically. The top plate portion 12 extends radially inward from the upper end of the upper outer peripheral wall portion 11. The upper inner peripheral wall portion 13 is formed in a cylindrical shape extending (protruding) downward from the radially inner edge portion of the top plate portion 12. An opening portion 14 is formed at the lower end of the upper inner peripheral wall portion 13. The flange portion 15 extends radially outward from the lower end of the upper outer peripheral wall portion 11.

[0030] The lower shell 2 has a lower outer peripheral wall portion 21, a bottom plate portion 22, and a lower inner peripheral wall portion 23, and is formed into a bottomed cylindrical shape with a closed lower end. The lower outer peripheral wall portion 21 is formed into a cylindrical shape extending vertically. The bottom plate portion 22 extends radially inward from the lower end of the lower outer peripheral wall portion 21. The lower inner peripheral wall portion 23 is formed into a cylindrical shape extending (protruding) upward from the radially inner edge portion of the bottom plate portion 22. An opening 24 is formed in the upper end of the lower inner peripheral wall portion 23.

[0031] The intermediate shell 3 has an intermediate outer peripheral wall portion 31, an intermediate plate portion 32, an intermediate inner peripheral wall portion 33, and a cover wall portion 34, and is formed in a bottomed tubular shape with a closed lower end. The intermediate plate portion 32 extends radially inward from a lower end of the intermediate outer peripheral wall portion 31. The intermediate inner peripheral wall portion 33 is formed in a cylindrical shape extending (protruding) upward from a radially inner edge portion of the intermediate plate portion 32. The cover wall portion 34 closes an upper end portion of the intermediate inner peripheral wall portion 33.

[0032] As shown in FIG. 1 , the upper outer peripheral wall portion 11, the upper inner peripheral wall portion 13 of the upper shell 1, the lower outer peripheral wall portion 21, the lower inner peripheral wall portion 23 of the lower shell 2, the intermediate outer peripheral wall portion 31, and the intermediate plate portion 32 of the intermediate shell 3 are arranged coaxially with the central axis A1 of the outer housing 10.

[0033] The upper shell 1, the lower shell 2, and the intermediate shell 3 are formed of a metal material. The metal material for forming these is not particularly limited, but examples include iron and stainless steel. As shown in FIG. 1, the upper shell 1 is disposed on the upper side, the lower shell 2 is disposed on the lower side, and the intermediate shell 3 is disposed between the upper shell 1 and the lower shell 2. The lower inner peripheral wall portion 23 of the lower shell 2 is inserted into the intermediate inner peripheral wall portion 33 of the intermediate shell 3, and in this state, the flange portion 15 of the upper shell 1 and the intermediate outer peripheral wall portion 31 of the intermediate shell 3 are joined, and the intermediate plate portion 32 of the intermediate shell 3 and the lower outer peripheral wall portion 21 of the lower shell 2 are joined. For example, laser welding can be used to join the respective members.

[0034] [1st rupture disc] The first rupture disc 6 is a plate-shaped member that covers the opening 24 of the lower shell 2 to close the opening 24, and is configured to be ruptured by energy generated by the actuation of the igniter 4. The first rupture disc 6 is made of a metal material. The metal material forming the first rupture disc 6 is not particularly limited, but examples include iron and stainless steel. The first rupture disc 6 is fixed to the lower inner peripheral wall portion 23 by joining its peripheral portion to the upper end portion of the lower inner peripheral wall portion 23 by laser welding or the like.

[0035] [Second rupture disc] The second rupture disc 7 is a plate-like member that covers the opening 14 of the upper shell 1 to close the opening 14, and is configured to be ruptured by energy generated by the activation of the igniter 4. The second rupture disc 7 is made of a metal material such as iron or stainless steel, similar to the first rupture disc 6. The second rupture disc 7 is fixed to the upper inner peripheral wall 13 by joining its peripheral portion to the lower end of the upper inner peripheral wall 13 by laser welding or the like.

[0036] [Outer housing] The outer shell housing 10 is formed by the lower outer peripheral wall portion 21 and the bottom plate portion 22 of the upper shell 1 and the lower shell 2, and the intermediate outer peripheral wall portion 31 and part of the intermediate plate portion 32 of the intermediate shell 3. More specifically, a portion of the intermediate plate portion 32 that is radially outward from the joint with the lower outer peripheral wall portion 21 of the lower shell 2 constitutes part of the outer shell housing 10.

[0037] [First partition wall] As shown in FIG. 1, the inner space of the outer housing 10 is divided by a first partition wall 30. The first partition wall 30 is formed by a part of the lower inner peripheral wall 23 of the lower shell 2. The first partition wall 30 defines an ignition chamber S10 in which the ignition means 20 is accommodated and a gas-filled chamber S20 in which gas is filled, inside the outer housing 10. The ignition chamber S10 is a space surrounded by the first partition wall 30 in the inner space of the outer housing 10, and is maintained at atmospheric pressure by closing a first communication portion 40 described later. The gas-filled chamber S20 is a space outside the first partition wall 30 in the inner space of the outer housing 10, and is in a pressurized state by being filled with pressurized gas.

[0038] [Ignition means] The ignition means 20 includes an igniter 4 housed in the ignition chamber S10. The igniter 4 includes an ignition section 41 housing an ignition charge, and a conductive section 42 to which an ignition current for igniting the ignition charge is supplied. The igniter 4 is configured such that, when activated by an ignition current supplied to the conductive section 42, the ignition section 41 is cleaved to release combustion products (flame, etc.) of the ignition charge. Reference numeral 411 in FIG. 1 indicates a release section that is cleaved when the igniter 4 is activated to release the combustion products. The release section 411 faces upward.

[0039] The ignition charge used in the igniter 4 is not limited, but examples include explosives containing zirconium and potassium perchlorate (ZPP), explosives containing titanium hydride and potassium perchlorate (THPP), explosives containing titanium and potassium perchlorate (TiPP), explosives containing aluminum and potassium perchlorate (APP), explosives containing aluminum and bismuth oxide (ABO), explosives containing aluminum and molybdenum oxide (AMO), explosives containing aluminum and copper oxide (ACO), explosives containing aluminum and iron oxide (AFO), or explosives consisting of a combination of two or more of these explosives.

[0040] The ignition means 20 may further include a solid gas generating agent depending on the energy required to break the communication part and the discharge part described later. The gas generating agent is accommodated in the ignition chamber S10, and generates gas by being burned by the combustion products discharged from the igniter 4 when the igniter 4 is activated. The gas generating agent may also be disposed adjacent to the ignition charge inside the ignition part 41. The gas generating agent may be, for example, a single-hole cylindrical agent made of guanidine nitrate (41% by weight), basic copper nitrate (49% by weight), binders and additives. The gas generating agent is not limited to this.

[0041] Here, "energy generated by the actuation of the igniter" in this example includes energy released from the igniter 4 (shock waves and flames due to the release of combustion products, high-temperature gas, etc.) and energy (pressure rise, etc.) due to the combustion of the ignition charge. In the case where the ignition means 20 includes a gas generating agent, energy (pressure rise, etc.) due to the combustion of the gas generating agent caused by the actuation of the igniter 4 is also included in "energy generated by the actuation of the igniter". In other words, in this specification, "energy generated by the actuation of the igniter" refers to energy generated primarily or secondarily by the actuation of the igniter.

[0042] [Holding material] The holding member 5 is a resin member disposed between the igniter 4 and the lower inner peripheral wall portion 23 of the lower shell 2 and integrally joins the igniter 4 and the lower inner peripheral wall portion 23. The holding member 5 fills an annular gap formed between the igniter 4 and the lower inner peripheral wall portion 23. This seals the internal space of the ignition chamber S10. The holding member 5 covers the igniter 4 such that the emission portion 411 of the igniter 4 is exposed from the holding member 5 to the ignition chamber S10 and the tip portion of the conductive portion 42 is exposed from the holding member 5 to the external space of the outer shell housing 10. The holding member 5 also covers the inner peripheral surface of the lower inner peripheral wall portion 23 such that a connector insertion space 51, into which a power supply connector (not shown) can be inserted, is formed inside the lower inner peripheral wall portion 23.

[0043] [1st communication section] The first partition portion 30 is provided with a first communication portion 40 that is configured to be closed before the igniter 4 is activated and to open upon activation of the igniter 4, thereby communicating between the ignition chamber S10 and the gas-filled chamber S20 (more specifically, the first filled chamber S1). The first communication portion 40 is formed by an opening 24 formed in the first partition portion 30 and a first rupture plate 6 that closes the opening 24. Before the igniter 4 is activated, the opening 24 is closed by the first rupture plate 6, and when the igniter 4 is activated, the first rupture plate 6 is ruptured by the energy generated by the activation of the igniter 4, thereby opening the first rupture plate 6. The communication part 40 opens, and the ignition chamber S10 and the gas-filled chamber S20 communicate with each other. Before the igniter 4 is activated, the first communication part 40 is closed, so that the ignition chamber S10 is maintained at atmospheric pressure and the igniter 4 is prevented from being exposed to pressurized gas.

[0044] 1, in this embodiment, the emission part 411 of the igniter 4 and the first communication part 40 are disposed opposite to each other. Therefore, when the igniter 4 is activated, energy (shock waves, flames, high-temperature gas, etc.) is emitted from the igniter 4 toward the first rupturable disc 6, which makes it easier for the first rupturable disc 6 to rupture.

[0045] [Discharge section] The outer shell housing 10 is provided with a discharge part 50 that is closed before the igniter 4 is activated and opens upon activation of the igniter 4 to communicate between the gas-filled chamber S20 (more specifically, the second filled chamber S2) and the outside of the outer shell housing 10 (more specifically, the diffusion chamber S30). The discharge part 50 is formed by an opening 14 formed in the outer shell housing 10 and a second rupture plate 7 that closes the opening 14. Before the igniter 4 is activated, the opening 14 is closed by the second rupture plate 7, and when the igniter 4 is activated, the second rupture plate 7 is ruptured by receiving energy generated by the activation of the igniter 4, thereby opening the discharge part 50 and communicating between the gas-filled chamber S20 and the outside of the outer shell housing 10.

[0046] [Second partition wall] As shown in FIG. 1, the gas-filled chamber S20 is partitioned by a second partition wall 60. The second partition wall 60 is formed by a part of the intermediate plate portion 32 of the intermediate shell 3, the intermediate inner peripheral wall portion 33, and the cover wall portion 34. More specifically, a part of the intermediate plate portion 32 radially inward from a joint portion with the lower outer peripheral wall portion 21 of the lower shell 2 constitutes a part of the second partition wall 60. The second partition wall 60 defines a first filled chamber S1 adjacent to the first communication portion 40 and a second filled chamber S2 adjacent to the discharge portion 50 inside the gas-filled chamber S20. The first filled chamber S1 is a space surrounded by the second partition wall 60 in the gas-filled chamber S20, and is defined by the lower shell 2 and the intermediate shell 3. The second filled chamber S2 is a space outside the second partition wall 60 in the gas-filled chamber S20, and is defined by the upper shell 1 and the intermediate shell 3.

[0047] [Second communication section] The second partition 60 is provided with a second communication portion 70 that is closed before the igniter 4 is activated and opens when the igniter 4 is activated to communicate between the first filling chamber S1 and the second filling chamber S2. The second communication portion 70 is formed as a part of the second partition 60 so as to be torn when the igniter 4 is activated. More specifically, the second communication portion 70 is formed by the central portion of the cover wall portion 34 that constitutes the second partition 60, and protrudes in a dome shape toward the second filling chamber S2. Before the igniter 4 is activated, communication between the first filling chamber S1 and the second filling chamber S2 is blocked, and when the igniter 4 is activated, the central portion of the cover wall portion 34 is torn by receiving energy generated by the activation of the igniter 4, so that the second communication portion 70 opens and the first filling chamber S1 and the second filling chamber S2 communicate with each other.

[0048] 1, in this example, the first communication part 40 and the second communication part 70 are disposed opposite to each other. Therefore, when the igniter 4 is activated, energy (shock waves, high-temperature gas, etc.) is released from the opened first communication part 40 toward the second communication part 70, making the second communication part 70 more likely to break open.

[0049] Here, the second communication part 70 protrudes towards the second packing chamber S2 side. In other words, the second communication part 70 protrudes to the outside of the first packing chamber S1. Therefore, the second communication part 70 has a strength against energy from the first packing chamber S1 side compared to the strength against energy from the second packing chamber S2 side. This also makes it easier for the second communication portion 70 to break when the igniter 4 is activated.

[0050] The advantage of forming the second communication part 70 in a dome shape is as follows. When manufacturing the gas generator 100, one of the first filling chamber S1 and the second filling chamber S2 is filled with pressurized gas, and then the other is filled with pressurized gas. At this time, the second communication part 70 is deformed in a convex shape toward the other filling chamber by the pressure of the pressurized gas that has been filled into one filling chamber first, and then the second communication part 70 is pushed back by the pressure of the pressurized gas that has been filled into the other filling chamber, and is deformed in a convex shape toward the one filling chamber, and so on. If this uneven deformation is repeated, this is not preferable in terms of strength against the pressurized gas. In contrast, in this example, the second communication part 70 is formed in advance in a dome shape that protrudes toward the second filling chamber S2, so that the second communication part 70 is less likely to deform in response to a pressure rise in the second filling chamber S2. Therefore, when the first filling chamber S1 is filled with pressurized gas first, and even when the second filling chamber S2 is filled with pressurized gas first, the second communication part 70 is prevented from deforming in a convex shape toward the first filling chamber S1. That is, at least the convex deformation toward the first filling chamber S1 is prevented. Therefore, by forming the second communication part 70 in a dome shape, the second communication part 70 is prevented from repeatedly deforming in a convex shape when filled with pressurized gas.

[0051] Furthermore, the second communication portion 70 is formed to be thinner than other portions of the second partition portion 60 (i.e., portions of the second partition portion 60 excluding the second communication portion 70). Therefore, the second communication portion 70 is weaker than other portions of the second partition portion 60. This also makes the second communication portion 70 more likely to break when the igniter 4 is activated.

[0052] Here, FIG. 2 is a diagram for explaining the second communication part 70 according to the embodiment. In FIG. 2, the upper end surface of the cover wall part 34 of the intermediate shell 3 is illustrated. As shown in FIG. 2, a plurality of V-shaped (triangular in cross section) grooves G1 extending linearly are formed in the second communication part 70. The plurality of grooves G1 extend radially in the radial direction starting from the central part which is the top of the cover wall part 34. As shown in FIG. 2, in this example, eight grooves G1 are formed at equal angular intervals. However, the technology of the present disclosure is not limited to this. In addition, the shape of the groove G1 is not limited to the V-shape, and the cross section may be a square or a semicircular shape.

[0053] The portion of the second communication part 70 where the groove G1 is formed is a linear weak portion 701 formed to be thinner than other portions of the second communication part 70. The weak portion 701 is weaker than other portions (i.e., portions of the second communication part 70 excluding the weak portion 701) and is easily broken. The second communication part 70 has the linear weak portion 701 which is preferentially easy to break, so that the second communication part 70 is easy to break when the igniter 4 is activated while ensuring strength against the pressurized gas. In this example, a plurality of weak portions 701 are formed, and all of the weak portions 701 intersect at the center of the second communication part 70. Note that the strength of the portions where the weak portions 701 intersect is particularly reduced, so that only some of the weak portions 701 may intersect, or none of the weak portions 701 may intersect, taking into consideration the strength against the pressurized gas. The intersecting portions of the groove G1 may be formed shallow. FIG. 3 is a diagram for explaining a modified example of the second communication part 70. As shown in Fig. 3, in the second communication portion 70 according to the modified example, the weak portions 701 do not intersect at the center. In other words, the weak portions 701 are formed in the second communication portion 70 except for the center (top). Although the second communication portion 70 shown in Figs. 2 and 3 has a plurality (eight) of weak portions 701, the number of weak portions 701 does not have to be a plurality, and there may be only one. Furthermore, although the weak portions 701 in this example are formed as solid lines extending continuously, the weak portions 701 may be formed as broken or dotted lines extending intermittently.

[0054] As shown in FIG. 1, in this embodiment, the second communication part 70 and the discharge part 50 are disposed opposite to each other. Therefore, when the igniter 4 is activated, the second communication part 70 opens toward the second rupture plate 7. Energy (shock waves, high-temperature gas, etc.) is released, making the second rupture plate 7 more likely to rupture.

[0055] [First filling chamber] The first filling chamber S1 has a first axial region S11 and a first radial region S12. The first axial region S11 is adjacent to the ignition chamber S10 in the axial direction across the first partition wall portion 30, and is disposed above the ignition chamber S10. The first axial region S11 is sandwiched in the axial direction between the first communication portion 40 and the second communication portion 70. The first radial region S12 is formed in a cylindrical shape so as to radially surround the ignition chamber S10 across the first partition wall portion 30, and is disposed radially outside the ignition chamber S10.

[0056] [Second filling chamber] The second filling chamber S2 has a second axial region S21 and a second radial region S22. The second axial region S21 is adjacent to the first axial region S11 of the first filling chamber S1 in the axial direction across the second partition wall 60, and is disposed above the first axial region S11. The second axial region S21 is axially sandwiched between the second communication portion 70 and the discharge portion 50. The second radial region S22 is formed in a cylindrical shape so as to radially surround the first radial region S12 of the first filling chamber S1 across the second partition wall 60, and is disposed radially outside the first radial region S12.

[0057] [gas] The second filling chamber S2 is filled with hydrogen as a fuel gas in a compressed state. However, the fuel gas according to the present disclosure is not limited to hydrogen gas. The fuel gas is not particularly limited, but may be, for example, a flammable gas such as hydrogen, methane, ethane, propane, butane, or a mixed gas containing at least one of these gases.

[0058] In addition, the first filling chamber S1 is filled with oxygen as an oxidizing gas in a compressed state. However, the oxidizing gas according to the present disclosure is not limited to oxygen gas. The oxidizing gas is not particularly limited, but examples thereof include simple gases such as oxygen and nitrous oxide, and mixture gases such as air, which are combustion-supporting gases.

[0059] In the gas generator according to the present disclosure, the first filling chamber may be filled with fuel gas, and the second filling chamber may be filled with oxidizing gas. In other words, in the gas generator according to the present disclosure, it is sufficient that one of the first filling chamber and the second filling chamber is filled with fuel gas, and the other is filled with oxidizing gas. In addition, the gas filled in the filling chamber does not have to be in a pressurized state.

[0060] Also, the fuel gas may be filled into one of the first and second filling chambers together with the inert gas. Also, the oxidizing gas may be filled into the other of the first and second filling chambers together with the inert gas. That is, in this example, the second filling chamber S2 may be filled with hydrogen gas and an inert gas, and the first filling chamber S1 may be filled with oxygen gas and an inert gas. By making the fuel gas and the oxidizing gas coexist with the inert gas, the combustion temperature of the mixed gas can be lowered and controlled. The pressurized state of the filling chamber may be formed by an inert gas. The inert gas is not particularly limited, but examples thereof include low-reactivity gases such as nitrogen, argon, helium, and carbon dioxide.

[0061] [Hydrogen resistant membrane] Here, the wall surface of the second filling chamber S2 filled with hydrogen gas is coated with a hydrogen embrittlement resistant film C1 made of a material having hydrogen barrier properties in order to prevent hydrogen embrittlement caused by contact of the metal surface constituting the wall surface with hydrogen. The hydrogen embrittlement resistant film C1 is provided on the surfaces of the upper shell 1 and the intermediate shell 3 that define the second filling chamber S2. The brittle film C1 may be configured to suppress the penetration of hydrogen into the metal surface. The material of the hydrogen embrittlement resistant film C1 is not limited as long as it has hydrogen barrier properties, and may be a resin material, a metal material, or a ceramic material.

[0062] Examples of the resin material forming the hydrogen embrittlement-resistant film C1 include ethylene vinyl alcohol copolymer resin and polyamide 6, examples of the metal material include A6061-T6 aluminum alloy, and examples of the ceramic material include aluminum oxide and titanium oxide. Specific examples of the configuration of the hydrogen embrittlement-resistant film C1 include the Al-5Mg spray coating described in JP 2018-141214 A, the coating with a relatively high hydrogen cut rate described in Table 1 of JP 2021-139034 A, and the ceramic thin film described in JP 2007-9276 A.

[0063] In this example, the hydrogen embrittlement-resistant film C1 is coated on the wall surface of the second filling chamber S2, but when the first filling chamber S1 is filled with hydrogen gas, the hydrogen embrittlement-resistant film C1 is coated on the wall surface of the first filling chamber S1. In other words, it is sufficient that the hydrogen embrittlement-resistant film C1 is coated on the wall surface of either the first filling chamber S1 or the second filling chamber S2 that is filled with hydrogen gas. However, in the gas generator according to the present disclosure, the hydrogen embrittlement-resistant film is not an essential component.

[0064] [Diffuser housing] The diffuser housing 8 is formed in a bottomed cylindrical shape that extends vertically and has a closed upper end. More specifically, the diffuser housing 8 has a cylindrical peripheral wall portion 81 that extends vertically, and a cover wall portion 82 that closes the upper end of the peripheral wall portion 81. A lower end portion of the peripheral wall portion 81 (corresponding to one end portion of the diffuser housing according to the present disclosure) is joined to the outer shell housing 10 such that the discharge portion 50 of the outer shell housing 10 is located inside the peripheral wall portion 81. As a result, a diffusion chamber S30 that is in communication with the gas-filled chamber S20 via the discharge portion 50 is formed inside the diffuser housing 8.

[0065] A plurality of gas discharge holes 83 are formed in the peripheral wall portion 81 of the diffuser housing 8, which communicate between the diffusion chamber S30 and the outside of the gas generator 100. When the igniter 4 is activated, the working gas from the gas filled chamber S20 passes through the diffusion chamber S30 and is released to the outside via the gas discharge holes 83. The number of gas discharge holes 83 is not particularly limited, and does not have to be multiple.

[0066] [filter] The filter 9 is a cylindrical member that extends vertically with both ends open, and is disposed between the exhaust part 50 and the gas exhaust hole 83 inside the diffusion chamber S30, with its upper end supported by the cover wall part 82 of the diffuser housing 8 and its lower end supported by the top plate part 12 of the upper shell 1. The filter 9 has multiple holes formed therein so as to enable filtering and cooling of the working gas.

[0067] [Layout of igniter, communication section and exhaust section] As shown in FIG. 1, in this example, the igniter 4, the first communicating portion 40, the second communicating portion 70, and the discharge portion 50 are arranged on the same straight line. Here, the fact that a plurality of members are "arranged on the same straight line" means that there may be a straight line passing through the plurality of members. In this example, the central axis A1 of the outer shell housing 10 passes through the igniter 4, the first communicating portion 40, the second communicating portion 70, and the discharge portion 50 as the same straight line. In other words, the igniter 4, the first communicating portion 40, the second communicating portion 70, and the discharge portion 50 are arranged on the central axis A1.

[0068] The arrangement of the igniter 4, the first communication portion 40, the second communication portion 70, and the exhaust portion 50 on the same straight line means that the first communication portion 40, the second communication portion 70, and the exhaust portion 50 are aligned in a straight line in the direction in which the combustion products are released from the release portion 411 of the igniter 4 (upward in this example). This means that when the igniter 4 is activated, the first communicating portion 40, the second communicating portion 70, and the exhaust portion 50 can be easily opened all at once by the energy (shock waves, flame, high-temperature gas, etc.) released from the igniter 4. In other words, it is easy to open all of the first communicating portion 40, the second communicating portion 70, and the exhaust portion 50 with one igniter. In addition, since the path from the igniter 4 to the diffusion chamber S30 is linear, the combustion products released from the igniter 4 can easily reach the diffusion chamber S30, and the mixed gas in the diffusion chamber S30 can be easily ignited. Furthermore, in the gas generator 100 according to this embodiment, the igniter 4, the first communicating portion 40, the second communicating portion 70, and the exhaust portion 50 are arranged close to each other in the axial direction (vertical direction), so that it is even easier to open all of them.

[0069] Furthermore, by arranging the igniter 4, the first communicating portion 40, the second communicating portion 70, and the discharge portion 50 on the central axis A1 of the outer shell housing 10, the gas generator 100 can have an axially symmetrical structure with respect to the central axis A1. This makes it easy to manufacture the gas generator 100. Furthermore, by making the gas generator 100 have an axially symmetrical structure, it is possible to suppress output unevenness of the gas generator in the circumferential direction.

[0070] [Operation] Next, the operation of gas generator 100 according to the embodiment will be described. In a state in which gas generator 100 before activation shown in Fig. 1 is mounted on a vehicle, a connector (not shown) inserted into connector insertion space 51 is connected to conductive portion 42 of igniter 4, and power can be supplied to igniter 4. In this state, when a sensor (not shown) mounted on the vehicle detects an impact, power from an external power source (not shown) is supplied to conductive portion 42 via the connector, igniter 4 is activated, and the ignition charge in ignition portion 41 is burned.

[0071] FIG. 4 is a cross-sectional view showing a state in which the gas generator 100 according to the embodiment is activated. In FIG. 4, a cross section along the axial direction of the outer shell housing 10 is shown. When the igniter 4 is activated and the internal pressure of the ignition part 41 rises with the combustion of the ignition charge, the release part 411 is ruptured, and the combustion product of the ignition charge is released into the ignition chamber S10. At this time, the combustion product is released in the upward direction (axial direction). Since the first communication part 40 is disposed above the igniter 4 and facing the release part 411 of the igniter 4, as shown in FIG. 4, the first rupture plate 6 of the first communication part 40 is ruptured by receiving energy (shock waves, flame, high-temperature gas, etc.) released from the igniter 4. As a result, the first communication part 40 opens. In addition, since the second communication part 70 is disposed above the first communication part 40 and faces the first communication part 40, the second communication part 70 is ruptured by receiving the energy emitted from the opened first communication part 40. This opens the second communication part 70. Furthermore, since the discharge part 50 is disposed above the second communication part 70 and faces the second communication part 70, the second rupture plate 7 of the discharge part 50 is ruptured by receiving the energy emitted from the opened second communication part 70. This opens the discharge part 50. In this way, since the igniter 4, the first communication part 40, the second communication part 70, and the discharge part 50 are disposed on the same straight line, they are opened together by the energy emitted from the igniter 4.

[0072] The second communication part 70 provided in the second partition part 60 separating the first filling chamber S1 and the second filling chamber S2 is opened, so that the oxygen gas (oxidizing gas) filled in the first filling chamber S1 and the hydrogen gas (fuel gas) filled in the second filling chamber S2 can be mixed. The oxygen gas flows into the diffusion chamber S30 through the second communication part 70 and the discharge part 50 and diffuses. The hydrogen gas flows into the diffusion chamber S30 through the discharge part 50 and diffuses. As a result, the oxygen gas and the hydrogen gas are mixed in the diffusion chamber S30. Then, the combustion products discharged from the igniter 4 flow into the diffusion chamber S30 through the first communication part 40, the second communication part 70, and the discharge part 50, so that the mixed gas of the hydrogen gas and the oxygen gas is ignited and burned. As a result, water vapor, which is the gas for operating the airbag, is generated.

[0073] The working gas generated in the diffusion chamber S30 passes through the filter 9 and is discharged from the gas generator 100 through the gas discharge hole 83. In the process in which the working gas passes through the filter 9, fragments of the first rupture disc 6, the second rupture disc 7, and the cover wall portion 34 contained in the gas are captured by the filter 9. In addition, when the working gas passes through the filter 9, the working gas is cooled and filtered by the filter 9. And, since the gas discharge hole 83 is formed in the peripheral wall portion 81 of the diffuser housing 8, the working gas is discharged radially outward. Therefore, the gas flow, which was in the axial direction from the gas filled chamber S20 to the diffusion chamber S30, is changed to the radial direction by the diffuser housing 8.

[0074] The working gas discharged from the gas generator 100 is supplied to an airbag, causing the airbag to inflate and protect the vehicle occupants from impact.

[0075] [Actions and Effects] As described above, the gas generator 100 according to this embodiment has the following features: An outer shell housing 10; an ignition means 20 including an igniter 4 which is actuated to release combustion products; A first partition portion 30 that defines an ignition chamber S10 in which the ignition means 20 is accommodated and a gas-filled chamber S20 in which gas is filled, inside the outer shell housing 10; a first communication portion 40 provided in the first partition portion 30, which is closed before the igniter 4 is activated and opens upon activation of the igniter 4 to communicate between the ignition chamber S10 and the gas-filled chamber S20; an exhaust section 50 provided in the outer shell housing 10, which is closed before the igniter 4 is activated and opens upon activation of the igniter 4 to communicate the gas-filled chamber S20 with the outside of the outer shell housing 10; a second partition wall portion 60 that defines a first filled chamber S1 adjacent to the first communication portion 40 and a second filled chamber S2 adjacent to the discharge portion 50 inside the gas filled chamber S20; Hydrogen gas as a fuel gas filled in one of the first filling chamber S1 and the second filling chamber S2 (in this example, the second filling chamber S2); Oxygen gas as an oxidizing gas filled in the other of the first filling chamber S1 and the second filling chamber S2 (in this example, the first filling chamber S1); The second communication portion 70 is provided in the second partition portion 60, is closed before the igniter 4 is activated, and opens upon activation of the igniter 4 to communicate the first filling chamber S1 and the second filling chamber S2.

[0076] That is, gas generator 100 employs a structure in which second communication portion 70 provided in second partition portion 60 separating first filling chamber S1 and second filling chamber S2 is opened by activation of igniter 4, thereby mixing fuel gas and oxidizing gas. This makes it possible to mix fuel gas and oxidizing gas with a single igniter 4. Therefore, gas generator 100 according to the present embodiment can reduce the number of parts and simplify the structure compared to a gas generator having a structure in which gas is mixed within a chamber by filling separate containers connected to a common chamber with gas and opening each container with a separate igniter.

[0077] Furthermore, in gas generator 100 according to the present embodiment, igniter 4 and first communication part 40 are disposed opposite each other. This allows energy to be released from igniter 4 toward first communication part 40 when igniter 4 is activated, making it easier to open first communication part 40.

[0078] Furthermore, in gas generator 100 according to the present embodiment, first communication part 40 and second communication part 70 are disposed opposite each other. As a result, when igniter 4 is activated, energy can be released from the open first communication part 40 toward the second communication part 70, making it easier to open the second communication part 70.

[0079] Furthermore, in the gas generator 100 according to this embodiment, the second communication portion 70 and the discharge portion 50 face each other. Thereby, when the igniter 4 is activated, energy can be released from the opened second communication portion 70 toward the discharge portion 50, making it easier to open the discharge portion 50.

[0080] Moreover, in gas generator 100 according to the present embodiment, igniter 4, first communication portion 40, second communication portion 70, and exhaust portion 50 are arranged on the same straight line. This makes it easy to open first communication portion 40, second communication portion 70, and exhaust portion 50 all at once by energy released from igniter 4 when igniter 4 is activated.

[0081] Furthermore, the outer shell housing 10 according to the present embodiment is formed into a cylindrical shape with a bottom, and the igniter 4, the first communicating portion 40, the second communicating portion 70, and the exhaust portion 50 are disposed on the central axis A1 of the outer shell housing 10. This allows the gas generator 100 to have an axially symmetrical structure with respect to the central axis A1, which facilitates the manufacture of the gas generator 100 and suppresses output unevenness of the gas generator 100 in the circumferential direction.

[0082] However, in the gas generator according to the present disclosure, the arrangement of the igniter, the first communication portion, the second communication portion, and the discharge portion is not limited to the above-mentioned embodiment, and they do not have to be arranged in a straight line.

[0083] Moreover, the gas generator 100 according to the present embodiment further includes a cylindrical diffuser housing 8 having one end joined to the outer shell housing 10 so as to form therein a diffusion chamber S30 that is in communication with the gas-filled chamber S20 via the discharge portion 50, and a gas discharge hole 83 that communicates the diffusion chamber S30 with the outside of the gas generator 100 is formed in a peripheral wall portion 81 of the diffuser housing 8. This makes it possible to mix the fuel gas and the oxidizing gas in the diffusion chamber S30 and ignite them. Furthermore, since the gas discharge hole 83 is formed in the peripheral wall portion 81 of the diffuser housing 8, it is possible to change the flow of the gas from the axial direction to the radial direction. Note that the diffuser housing 8 is not an essential component of the gas generator according to the present disclosure. The gas generator according to the present disclosure may be configured to mix and ignite the gas in the filling chamber.

[0084] Furthermore, the fuel gas filled in gas generator 100 according to this embodiment is hydrogen gas, and the wall surface of the first filled chamber S1 or the second filled chamber S2, whichever is filled with hydrogen gas (the second filled chamber S2 in this example), is coated with a hydrogen embrittlement-resistant film C1. This makes it possible to prevent hydrogen embrittlement caused by the metal surface constituting the wall surface of the second filled chamber S2 coming into contact with hydrogen.

[0085] The second communication part 70 according to the present embodiment is formed as a part of the second partition part 60 so as to be ruptured by the activation of the igniter 4, and protrudes in a dome shape toward the second filling chamber S2. This suppresses convex deformation toward at least the first filling chamber S1, and prevents the second communication part 70 from repeatedly deforming in a convex shape when the pressurized gas is filled. As a result, the strength of the second communication part 70 against the pressurized gas can be improved.

[0086] Furthermore, the second communication portion 70 according to this embodiment is formed to be thinner than other portions of the second partition portion 60. This makes the second communication portion 70 more likely to break when the igniter 4 is activated.

[0087] Furthermore, the second communicating portion 70 has a linear weakened portion 701 that is formed to be thinner than other portions of the second communicating portion 70. This makes the second communicating portion 70 more likely to break when the igniter 4 is activated.

[0088] The second communication portion of the gas generator according to the present disclosure does not have to be a part of the second partition wall. The second communication portion is a portion of an opening formed in the second partition wall and a portion of the second partition wall that closes the opening before the igniter is activated. and a rupture disk that ruptures upon activation of the igniter.

[0089] Moreover, the first communication part 40 according to the present embodiment is formed by the opening 24 formed in the first partition part 30 and the first rupture plate 6 that closes the opening 24 before the activation of the igniter 4 and ruptures when the igniter 4 is activated. This allows the first communication part 40 to be opened by the activation of the igniter 4. Note that the first communication part according to the present disclosure is not limited to the above-mentioned aspect, and may be formed as a part of the first partition part so as to rupture when the igniter is activated, for example.

[0090] Furthermore, the discharge portion 50 according to the present embodiment is formed by the opening 14 formed in the outer shell housing 10 and the second rupture plate 7 that closes the opening 14 before the activation of the igniter 4 and ruptures when the igniter 4 is activated. This allows the discharge portion 50 to be opened by activation of the igniter 4. Note that the discharge portion according to the present disclosure is not limited to the above-mentioned aspect, and may be formed as a part of the outer shell housing so as to rupture when the igniter is activated, for example.

[0091] The ignition means according to the present disclosure may include a gas generating agent disposed in the ignition chamber and combusted by the activation of the igniter. This can increase the energy generated by the activation of the igniter. In other words, the energy required to open the first communication portion, the second communication portion, and the discharge portion can be increased. For example, when the igniter, the first communication portion, the second communication portion, and the discharge portion are not disposed on the same straight line and the energy released from the igniter alone is insufficient, the energy can be supplemented by disposing a gas generating agent in the ignition chamber.

[0092] The first filling chamber S1 according to the present embodiment has a first axial region S11 adjacent to the ignition chamber S10 in the axial direction of the outer shell housing 10 across the first partition wall 30, and a cylindrical first radial region S12 surrounding the ignition chamber S10 from the radial direction of the outer shell housing 10 across the first partition wall 30. The second filling chamber S2 according to the present embodiment has a second axial region S21 adjacent to the first axial region S11 of the first filling chamber S1 in the axial direction of the outer shell housing 10 across the second partition wall 60, and a cylindrical second radial region S22 surrounding the first radial region S12 of the first filling chamber S1 from the radial direction of the outer shell housing 10 across the second partition wall 60. The ignition chamber S10, the first axial region S11, and the second axial region S21 are arranged in order from the lower side to the upper side in the axial direction. Moreover, the ignition chamber S10, the first radial region S12, and the second radial region S22 are arranged in order from the inside to the outside in the radial direction. The first filling chamber S1 has the cylindrical first radial region S12, so that the length of the first filling chamber S1 in the axial direction can be shortened while ensuring a volume for filling with gas. Similarly, the second filling chamber S2 has the cylindrical second radial region S22, so that the length of the second filling chamber S2 in the axial direction can be shortened while ensuring a volume for filling with gas. As a result, the axial length of the gas generator 100 can be shortened, and the gas generator 100 can be made smaller. Furthermore, in the gas generator 100 according to the embodiment, the first communication portion 40, the second communication portion 70, and the discharge portion 50 are disposed on the central axis A1 of the outer shell housing 10, and therefore by shortening the axial lengths of the first filling chamber S1 and the second filling chamber S2, it is possible to shorten the distance between the first communication portion 40 and the second communication portion 70 and the distance between the second communication portion 70 and the discharge portion 50. This makes it possible to easily open the second communication portion 70 and the discharge portion 50 when the igniter 4 is activated.

[0093] Here, as shown in Fig. 1, an outer shell container constituted by the outer shell housing 10 and the diffuser housing 8 is defined as a gas generator housing 80. The length of the gas generator housing 80 in the axial direction is defined as L1, and the width in the radial direction is defined as W1. The gas generator housing 80 of the gas generator 100 according to this embodiment is formed in a short cylindrical shape such that the length L1 in the axial direction is shorter than the width W1 in the radial direction. This enables the gas generator 100 to be made smaller in size.

[0094] <Other> Although the embodiments of the technology according to the present disclosure have been described above, each aspect disclosed in this specification can be combined with any other features disclosed in this specification. [Explanation of symbols]

[0095] 4...Igniter 6...1st rupture disc 7...Second rupture disc 8. Diffuser housing 10....Outer housing 20...Ignition means 30...First bulkhead part 40...1st communication section 50...Discharge section 60...Second bulkhead part 70...Second communication part 80 Gas generator housing 100 Gas generator C1...Hydrogen resistant membrane S1...1st filling chamber S2...Second filling chamber S10...Ignition chamber S20 Gas filling chamber

Claims

1. A housing shell, ignition means including an igniter that releases combustion products when activated, a first partition portion that defines an ignition chamber in which the ignition means is housed and a gas filling chamber filled with gas inside the housing shell, a first communication portion provided in the first partition portion, which is closed before the operation of the igniter and opens by the operation of the igniter to communicate the ignition chamber and the gas filling chamber, a discharge portion provided in the housing shell, which is closed before the operation of the igniter and opens by the operation of the igniter to communicate the gas filling chamber and the outside of the housing shell, a second partition portion that defines a first filling chamber adjacent to the first communication portion and a second filling chamber adjacent to the discharge portion inside the gas filling chamber, fuel gas filled in one of the first filling chamber and the second filling chamber, oxidizing gas filled in the other of the first filling chamber and the second filling chamber, and a second communication portion provided in the second partition portion, which is closed before the operation of the igniter and opens by the operation of the igniter to communicate the first filling chamber and the second filling chamber. A gas generator.

2. The igniter and the first communication portion are arranged opposite to each other. The gas generator according to Claim 1.

3. The first communication portion and the second communication portion are arranged opposite to each other. The gas generator according to Claim 1 or 2.

4. The second communication portion and the discharge portion are arranged opposite to each other. The gas generator according to Claim 1 or 2.

5. The igniter, the first communication portion, the second communication portion, and the discharge portion are arranged on the same straight line. The gas generator according to Claim 1.

6. The housing shell is formed in a bottomed cylindrical shape, and the igniter, the first communication portion, the second communication portion, and the discharge portion are arranged on the central axis of the housing shell. The gas generator according to Claim 5.

7. Further comprising a cylindrical diffuser housing having one end joined to the housing shell so as to form a diffusion chamber communicating with the gas filling chamber through the discharge portion inside, and gas discharge holes are formed in the peripheral wall portion of the diffuser housing to communicate the diffusion chamber and the outside of the gas generator. The gas generator according to Claim 1 or 2.

8. The fuel gas is filled in one of the first filling chamber and the second filling chamber together with an inert gas. The gas generator according to Claim 1 or 2.

9. ​ The fuel gas is hydrogen gas. The gas generator according to claim 1 or 2.

10. A hydrogen embrittlement resistant film is coated on the wall surface of the one of the first filling chamber and the second filling chamber filled with the hydrogen gas. The gas generator according to claim 9.

11. The oxidizing gas is filled in the other of the first filling chamber and the second filling chamber together with an inert gas. The gas generator according to claim 1 or 2.

12. The second communication part is formed as a part of the second partition wall part so as to be cleaved by the operation of the igniter, and protrudes in a dome shape toward the second filling chamber side. The gas generator according to claim 1 or 2.

13. The second communication part is formed thinner than other parts in the second partition wall part. The gas generator according to claim 12.

14. The second communication part has a linear weak part formed thinner than other parts in the second communication part. The gas generator according to claim 13.

15. The ignition means is disposed in the ignition chamber and includes a gas generating agent that burns by the operation of the igniter. The gas generator according to claim 1 or 2.

16. The first communication part is formed by an opening formed in the first partition wall part and a rupture plate that closes the opening before the operation of the igniter and is cleaved by the operation of the igniter. The gas generator according to claim 1 or 2.

17. The discharge part is formed by an opening formed in the outer shell housing and a rupture plate that closes the opening before the operation of the igniter and is cleaved by the operation of the igniter. The gas generator according to claim 1 or 2.

18. The outer shell housing is formed in a bottomed cylindrical shape. The first filling chamber has a first axial region adjacent to the ignition chamber in the axial direction of the outer shell housing with the first partition wall part interposed therebetween, and a cylindrical first radial region surrounding the ignition chamber from the radial direction of the outer shell housing with the first partition wall part interposed therebetween. The second filling chamber has a second axial region adjacent to the first axial region of the first filling chamber in the axial direction of the outer shell housing with the second partition wall part interposed therebetween, and a cylindrical second radial region surrounding the first radial region of the first filling chamber from the radial direction of the outer shell housing with the second partition wall part interposed therebetween. The gas generator according to claim 1 or 2. ​ A cylindrical diffuser housing having one end joined to the outer shell housing is further provided so as to form a diffusion chamber inside that communicates with the gas filling chamber through the discharge portion. A gas discharge hole that communicates the diffusion chamber with the outside of the gas generator is formed in the peripheral wall portion of the diffuser housing. The diffusion chamber is adjacent to the gas filling chamber in the axial direction of the outer shell housing with the wall of the outer shell housing interposed therebetween. The gas generator housing constituted by the outer shell housing and the diffuser housing is shorter in the axial direction than in the width in the radial direction. The gas generator according to claim 18.

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