Gas generator

Abstract

The gas generator is provided with: a first partition wall section that defines an ignition chamber in which an ignition unit is accommodated and a gas-filled chamber in which gas is filled in the interior of a housing case; a first communication part which is provided in the first partition wall part and which communicates the ignition chamber and the gas-filled chamber by being opened by the operation of the igniter; a discharge part which is provided in the housing case, and which opens by the operation of the igniter, thereby connecting the gas-filled chamber to the outside of the housing case; a second partition wall portion defining 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; a fuel gas filled in one of the first filling chamber and the second filling chamber; an oxidizing gas filled in the other one 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 communicates the first filling chamber and the second filling chamber by being opened by the operation of the igniter.

Description

Technical Field

[0001] The present disclosure relates to a gas generator. Background Art

[0002] In the past, the following gas generator is well known: a gas source is contained in a storage space formed in a housing, and gas is discharged to the outside by operating an igniter. Such a gas generator is used, for example, to supply gas to an airbag or a seat belt retractor. In this regard, the following airbag inflator is disclosed: a combustion gas (water vapor, etc.) is generated by igniting a mixed gas of an oxidized gas (fuel gas) such as hydrogen and an oxidizing gas such as oxygen, and the combustion gas is supplied to the airbag as a working gas, thereby inflating the airbag (for example, Patent Document 1). In the airbag inflator of Patent Document 1, a bottle containing an oxidized 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 igniting a squib, thereby discharging the gas of each bottle into the chamber, and the mixed gas is ignited.

[0003] Prior art literature

[0004] Patent Literature

[0005] Patent Document 1: U.S. Patent Application Publication No. 2010 / 0283231

[0006] Patent Document 2: U.S. Patent No. 5,582,806

[0007] Patent Document 3: Japanese Patent Application Laid-Open No. 9-20203 Summary of the invention

[0008] Problems to be solved by the invention

[0009] An object of the technology disclosed in the present invention is to simplify the structure of a gas generator using fuel gas and oxidizing gas.

[0010] Solution to the problem (Solution 1)

[0011] In order to solve the above and other problems, the gas generator of some embodiments of the present disclosure adopts the following structure. That is, the gas generator of the present disclosure has:

[0012] housing shell;

[0013] an ignition unit, including an igniter operable to discharge combustion products;

[0014] A first partition wall portion defines an ignition chamber for accommodating the ignition unit and a gas filling chamber for gas filling inside the housing shell;

[0015] a first connecting portion, provided at the first partition wall portion, which is closed before the igniter is operated and is opened by the operation of the igniter, thereby connecting the ignition chamber with the gas filling chamber;

[0016] a discharge portion, provided in the outer shell, which is closed before the igniter is operated and is opened by the operation of the igniter, thereby connecting the gas-filled chamber with the outside of the outer shell;

[0017] a second partition wall portion defining a first filling chamber adjacent to the first communicating portion and a second filling chamber adjacent to the discharge portion within the gas-filled chamber;

[0018] A fuel gas filled in one of the first filling chamber and the second filling chamber;

[0019] an oxidizing gas filled in the other of the first filling chamber and the second filling chamber; and

[0020] The second communication portion is provided in the second partition wall portion, is closed before the igniter is operated, and is opened by the operation of the igniter, thereby communicating the first filling chamber with the second filling chamber.

[0021] (Solution 2)

[0022] In the above-mentioned aspect 1, the igniter and the first communicating portion may be arranged to face each other.

[0023] (Solution 3)

[0024] In the above-mentioned solution 1 or 2, the first communicating portion and the second communicating portion may be arranged to face each other.

[0025] (Solution 4)

[0026] In any one of the above-mentioned aspects 1 to 3, the second communicating portion may be arranged to face the discharge portion.

[0027] (Scheme 5)

[0028] In any one of the above-mentioned aspects 1 to 4, the igniter, the first communicating portion, the second communicating portion, and the discharge portion may be arranged on the same straight line.

[0029] (Scheme 6)

[0030] In any one of the above schemes 1 to 5, the outer shell may be formed into a bottomed cylindrical shape.

[0031] The igniter, the first communicating portion, the second communicating portion, and the discharge portion are arranged on a central axis of the outer shell.

[0032] (Scheme 7)

[0033] Alternatively, the gas generator of any one of the above-mentioned schemes 1 to 6 further includes a cylindrical diffuser shell, one end of which is joined to the outer shell in such a manner that a diffusion chamber communicating with the gas filling chamber via the discharge portion is formed inside the diffuser shell.

[0034] A gas discharge hole that connects the diffusion chamber with the outside of the gas generator is formed in a peripheral wall portion of the diffuser housing.

[0035] (Scheme 8)

[0036] In any one of the above-mentioned aspects 1 to 7, the fuel gas may be filled together with an inert gas in one of the first filling chamber and the second filling chamber.

[0037] (Scheme 9)

[0038] In any one of the above-mentioned schemes 1 to 8, the fuel gas may be hydrogen.

[0039] (Scheme 10)

[0040] In the above-mentioned ninth aspect, a hydrogen embrittlement-resistant film may be coated on a wall surface of one of the first filling chamber and the second filling chamber that is filled with the hydrogen gas.

[0041] (Scheme 11)

[0042] In any one of the above-mentioned aspects 1 to 10, the oxidizing gas may be filled together with an inert gas in the other of the first filling chamber and the second filling chamber.

[0043] (Scheme 12)

[0044] In any one of the above-mentioned aspects 1 to 11, the second communication portion may be formed as a part of the second partition wall portion so as to be ruptured by the operation of the igniter and may protrude in a dome shape toward the second filling chamber side.

[0045] (Scheme 13)

[0046] In the above-mentioned aspect 12, the second communicating portion may be formed to be thinner than other portions of the second partition wall portion.

[0047] (Scheme 14)

[0048] In the above-mentioned aspect 12 or 13, the second communicating portion may include a linear fragile portion, and the fragile portion may be formed to be thinner than other portions of the second communicating portion.

[0049] (Scheme 15)

[0050] In any one of the above-mentioned aspects 1 to 14, the ignition unit may include a gas generating agent, the gas generating agent may be arranged in the ignition chamber, and the gas generating agent may be combusted by the operation of the igniter.

[0051] (Scheme 16)

[0052] In any one of the above schemes 1 to 15, the first connecting portion may be formed by an opening portion and a rupture plate, the opening portion is formed in the first partition wall portion, the rupture plate closes the opening portion before the igniter operates, and is ruptured by the operation of the igniter.

[0053] (Scheme 17)

[0054] In any one of the above schemes 1 to 5, the discharge portion may be formed by an opening portion and a rupture plate, the opening portion is formed in the outer shell, the rupture plate closes the opening portion before the igniter operates, and is ruptured by the operation of the igniter.

[0055] (Scheme 18)

[0056] In any one of the above schemes 1 to 17, the outer shell may be formed into a bottomed cylindrical shape.

[0057] The first filling chamber has a first axial region and a cylindrical first radial region, the first axial region is a region adjacent to the ignition chamber in the axial direction of the outer shell body through the first partition wall portion, and the first radial region is a region surrounding the ignition chamber from the radial direction of the outer shell body through the first partition wall portion.

[0058] The second filling chamber has a second axial region and a cylindrical second radial region, the second axial region is a region adjacent to the first axial region of the first filling chamber in the axial direction of the outer shell body via the second partition wall portion, and the second radial region is a region surrounding the first radial region of the first filling chamber from the radial direction of the outer shell body via the second partition wall portion.

[0059] (Scheme 19)

[0060] Alternatively, the gas generator of any one of the above-mentioned schemes 1 to 18 may further include a cylindrical diffuser shell, one end of which is joined to the outer shell in such a manner that a diffusion chamber communicating with the gas filling chamber via the discharge portion is formed inside the diffuser shell.

[0061] A gas discharge hole is formed on a peripheral wall portion of the diffuser housing to connect the diffusion chamber with the outside of the gas generator.

[0062] The diffusion chamber is adjacent to the gas-filled chamber in the axial direction of the outer shell via a wall of the outer shell.

[0063] The gas generator housing formed by the outer shell and the diffuser shell has an axial length that is shorter than a radial width.

[0064] Effects of the Invention

[0065] According to some embodiments of the present disclosure, the structure of a gas generator using fuel gas and oxidizing gas can be simplified. BRIEF DESCRIPTION OF THE DRAWINGS

[0066] Figure 1 It is a cross-sectional view showing a state of the gas generator according to the embodiment before operation.

[0067] Figure 2 It is a diagram for explaining the second communication portion according to the embodiment.

[0068] Figure 3 It is a diagram for explaining a modification example of the second communicating portion.

[0069] Figure 4 It is a cross-sectional view showing the operating state of the gas generator according to the embodiment. DETAILED DESCRIPTION

[0070] Hereinafter, embodiments of the present disclosure will be described with reference to the accompanying drawings. In the embodiments described below, a scheme for applying the technology of the present disclosure to a gas generator (inflator) for an airbag will be described. However, the use of the technology of the present disclosure is not limited thereto, and for example, it can also be applied to a gas generator for a seat belt retractor. It should be noted that each structure in each embodiment and their combination are examples, and additions, omissions, substitutions, and other changes to the structure can be appropriately made without departing from the scope of the subject matter of the present invention. The present disclosure is not limited to the embodiments, but only to the claims.

[0071] [Overall composition]

[0072] Figure 1 It is a cross-sectional view showing a state of gas generator 100 according to the embodiment before operation. Figure 11 shows a cross section along the axial direction of the housing shell indicated by reference numeral 10. The gas generator 100 is an airbag inflator, and is a device that supplies working gas for inflating an airbag (not shown) to the airbag during operation. The gas generator 100 is configured to ignite a mixed gas of hydrogen as an example of fuel gas and oxygen as an example of oxidizing gas to generate water vapor as a combustion gas, and supply the water vapor as airbag working gas (hereinafter referred to as working gas) to the airbag.

[0073] like Figure 1 As shown, the gas generator 100 includes an upper shell 1, a lower shell 2, an intermediate shell 3, an ignition unit 20, a retaining member 5, a first rupture plate 6, a second rupture plate 7, a diffuser housing 8, and a filter 9. The gas generator 100 is formed into a bottomed cylindrical shape with both ends closed. The details will be described later, but the upper shell 1, a part of the lower shell 2, and a part of the intermediate shell 3 form a Figure 1 The outer shell case 10 is shown in a dot pattern. The outer shell case 10 is formed in a bottomed cylindrical shape with both ends closed. Figure 1 The reference symbol A1 in the figure represents the central axis of the outer shell 10. Hereinafter, the direction along the axial direction of the outer shell 10 is defined as the up-down direction of the gas generator 100, and the lower shell 2 side (i.e. Figure 1 The lower side of the gas generator 100 is set as the lower side, and the opposite side (i.e., the upper shell 1, Figure 1 The upper side in the figure is set as the upper side of the gas generator 100. In addition, in the following description, unless otherwise specified, "axial direction" refers to the axial direction of the housing shell 10, "radial direction" refers to the radial direction of the housing shell 10, and "circumferential direction" refers to the circumferential direction of the housing shell 10. The following describes the various components of the gas generator 100.

[0074] [Upper shell / lower shell / middle shell]

[0075] 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 into a bottomed cylindrical shape with an upper end portion closed. The upper outer peripheral wall portion 11 is formed into a cylindrical shape extending up and down. The top plate portion 12 extends radially inward from the upper end portion of the upper outer peripheral wall portion 11. The upper inner peripheral wall portion 13 is formed into a cylindrical shape extending (protruding) downward from the radially inner edge of the top plate portion 12. An opening portion 14 is formed at the lower end portion of the upper inner peripheral wall portion 13. The flange portion 15 extends radially outward from the lower end portion of the upper outer peripheral wall portion 11.

[0076] 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 inwardly in the radial direction 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) upwardly from the radially inner edge of the bottom plate portion 22. An opening portion 24 is formed at the upper end of the lower inner peripheral wall portion 23.

[0077] The intermediate housing 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 into a bottomed cylindrical shape with a closed lower end. The intermediate outer peripheral wall portion 31 is formed into a cylindrical shape extending in the vertical direction. The intermediate plate portion 32 extends radially inward from the lower end of the intermediate outer peripheral wall portion 31. The intermediate inner peripheral wall portion 33 is formed into a cylindrical shape extending (protruding) upward from the radially inner edge of the intermediate plate portion 32. The cover wall portion 34 closes the upper end of the intermediate inner peripheral wall portion 33.

[0078] like Figure 1 As shown, the upper outer peripheral wall portion 11 and the upper inner peripheral wall portion 13 of the upper shell 1, the lower outer peripheral wall portion 21 and the lower inner peripheral wall portion 23 of the lower shell 2, the middle outer peripheral wall portion 31 and the middle plate portion 32 of the middle shell 3 are arranged coaxially with the central axis A1 of the outer shell case 10.

[0079] The upper shell 1, the lower shell 2 and the intermediate shell 3 are formed of metal materials. The metal materials forming them are not particularly limited, but examples thereof include iron, stainless steel, etc. Figure 1 As shown, the upper shell 1 is arranged on the upper side, the lower shell 2 is arranged on the lower side, and the intermediate shell 3 is arranged 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. In this state, the flange portion 15 of the upper shell 1 is joined to the intermediate outer peripheral wall portion 31 of the intermediate shell 3, and the intermediate plate portion 32 of the intermediate shell 3 is joined to the lower outer peripheral wall portion 21 of the lower shell 2. For joining of the components, for example, laser welding can be used.

[0080] [First rupture plate]

[0081] The first rupture plate 6 is a plate-shaped member that covers the opening 24 of the lower shell 2 to block the opening 24, and is configured to be ruptured by the energy generated by the operation of the igniter 4. The first rupture plate 6 is formed of a metal material. The metal material forming the first rupture plate 6 is not particularly limited, but iron, stainless steel, etc. can be exemplified. The peripheral edge of the first rupture plate 6 is joined to the upper end of the lower inner peripheral wall portion 23 by laser welding or the like, thereby fixing the first rupture plate 6 to the lower inner peripheral wall portion 23.

[0082] [Second rupture plate]

[0083] The second rupture plate 7 is a plate-shaped member that covers the opening 14 of the upper shell 1 to close the opening 14, and is configured to be ruptured by the energy generated by the operation of the igniter 4. The second rupture plate 7 is formed of a metal material such as iron or stainless steel as the first rupture plate 6. The peripheral edge of the second rupture plate 7 is joined to the lower end of the upper inner peripheral wall 13 by laser welding or the like, thereby fixing the second rupture plate 7 to the upper inner peripheral wall 13.

[0084] [Housing]

[0085] The outer shell 10 is formed by the upper shell 1, the lower outer peripheral wall portion 21 of the lower shell 2, the bottom plate portion 22, the intermediate outer peripheral wall portion 31 of the intermediate shell 3, and a part of the intermediate plate portion 32. More specifically, the portion of the intermediate plate portion 32 that is radially outward of the joint portion with the lower outer peripheral wall portion 21 of the lower shell 2 constitutes a part of the outer shell 10.

[0086] [First partition wall portion]

[0087] like Figure 1 As shown, the internal space of the outer shell 10 is divided by the first partition wall portion 30. The first partition wall portion 30 is formed by a portion of the lower inner peripheral wall portion 23 of the lower shell 2. The first partition wall portion 30 defines an ignition chamber S10 for accommodating the ignition unit 20 and a gas filling chamber S20 for gas filling inside the outer shell 10. The ignition chamber S10 is a space surrounded by the first partition wall portion 30 in the internal space of the outer shell 10, and is maintained at atmospheric pressure by closing the first connecting portion 40 described later. The gas filling chamber S20 is a space outside the first partition wall portion 30 in the internal space of the outer shell 10, and becomes a pressurized state by filling pressurized gas.

[0088] [Ignition unit]

[0089] The ignition unit 20 includes an igniter 4 accommodated in an ignition chamber S10. The igniter 4 includes an ignition portion 41 accommodating a primer and a conductive portion 42 to which an ignition current for igniting the primer is supplied. The igniter 4 is configured to operate by the ignition current supplied to the conductive portion 42, whereby the ignition portion 41 is ruptured to discharge a combustion product (flame, etc.) of the primer. Figure 1 Reference numeral 411 denotes a discharge portion that is broken apart and discharges combustion products when the igniter 4 is operated. The discharge portion 411 faces upward.

[0090] The explosive used for the igniter 4 is not limited, but examples thereof include a gunpowder containing zirconium and potassium perchlorate (ZPP), a gunpowder containing titanium hydride and potassium perchlorate (THPP), a gunpowder containing titanium and potassium perchlorate (TiPP), a gunpowder containing aluminum and potassium perchlorate (APP), a gunpowder containing aluminum and bismuth oxide (ABO), a gunpowder containing aluminum and molybdenum oxide (AMO), a gunpowder containing aluminum and copper oxide (ACO), a gunpowder containing aluminum and iron oxide (AFO), or a gunpowder consisting of a combination of a plurality of these gunpowders.

[0091] Alternatively, the ignition unit 20 may further include a solid gas generator according to the energy required for the cracking of the connecting portion and the discharge portion described later. The gas generator is contained in the ignition chamber S10. When the igniter 4 is working, the gas generator burns through the combustion products discharged from the igniter 4, thereby generating gas. In addition, the gas generator may also be arranged adjacent to the detonator inside the ignition portion 41. As the gas generator, for example, a single-hole cylindrical substance composed of guanidine nitrate (41 weight %), basic copper nitrate (49 weight %), a binder, and an additive may be used. The gas generator is not limited to this.

[0092] Here, the "energy generated by the operation of the igniter" in this example includes the energy discharged from the igniter 4 (shock waves, flames, high-temperature gases, etc. generated by the discharge of combustion products) and the energy generated by the combustion of the detonator (pressure increase, etc.). If the ignition unit 20 includes a gas generator, the energy (pressure increase, etc.) generated by the combustion of the gas generator caused by the operation of the igniter 4 is also included in the "energy generated by the operation of the igniter". That is, in this specification, the "energy generated by the operation of the igniter" refers to the energy generated once or twice by the operation of the igniter.

[0093] [Retaining member]

[0094] The retaining member 5 is a resin member that is 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 annular gap formed between the igniter 4 and the lower inner peripheral wall portion 23 is filled by the retaining member 5. Thus, the internal space of the ignition chamber S10 is sealed. The retaining member 5 covers the igniter 4 in the following manner: the discharge portion 411 of the igniter 4 is exposed from the retaining member 5 to the ignition chamber S10, and the top end portion of the conductive portion 42 is exposed from the retaining member 5 to the external space of the outer shell body 10. In addition, the retaining member 5 covers the inner peripheral surface of the lower inner peripheral wall portion 23 in the following manner: a connector insertion space 51 is formed on the inner side of the lower inner peripheral wall portion 23 as a space into which a power supply connector (not shown) can be inserted.

[0095] [First communication portion]

[0096] The first connecting portion 40 is provided in the first partition wall portion 30. The first connecting portion 40 is configured to be closed before the igniter 4 is operated, and to be opened by the operation of the igniter 4, thereby connecting the ignition chamber S10 with the gas filling chamber S20 (more specifically, the first filling chamber S1). The first connecting portion 40 is formed by the opening portion 24 formed in the first partition wall portion 30 and the first rupture plate 6 that blocks the opening portion 24. Before the igniter 4 is operated, the opening portion 24 is blocked by the first rupture plate 6. When the igniter 4 is operated, the first rupture plate 6 is cracked by the energy generated by the operation of the igniter 4, thereby opening the first connecting portion 40 and connecting the ignition chamber S10 with the gas filling chamber S20. Before the igniter 4 is operated, the first connecting portion 40 is closed, so that the ignition chamber S10 is maintained at atmospheric pressure, and in addition, the igniter 4 is prevented from being exposed to pressurized gas.

[0097] like Figure 1 As shown, in this example, the discharge portion 411 of the igniter 4 is disposed opposite to the first communication portion 40. Therefore, when the igniter 4 is operated, energy (shock wave, flame, high temperature gas, etc.) is discharged from the igniter 4 toward the first rupture plate 6, so that the first rupture plate 6 is easily ruptured.

[0098] [Discharge section]

[0099] The housing case 10 is provided with a discharge portion 50, which is configured to be closed before the igniter 4 is operated, and to be opened by the operation of the igniter 4, thereby connecting the gas filling chamber S20 (more specifically, the second filling chamber S2) with the outside of the housing case 10 (more specifically, the diffusion chamber S30). The discharge portion 50 is formed by the opening portion 14 formed in the housing case 10 and the second rupture plate 7 that blocks the opening portion 14. Before the igniter 4 is operated, the opening portion 14 is blocked by the second rupture plate 7. When the igniter 4 is operated, the second rupture plate 7 receives the energy generated by the operation of the igniter 4 and ruptures, thereby opening the discharge portion 50, and the gas filling chamber S20 is connected with the outside of the housing case 10.

[0100] [Second partition wall portion]

[0101] like Figure 1As shown, the gas-filled chamber S20 is divided by the second partition wall portion 60. The second partition wall portion 60 is formed by a portion 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 portion of the intermediate plate portion 32 that is radially inward of the joint portion with the lower outer peripheral wall portion 21 of the lower shell 2 constitutes a portion of the second partition wall portion 60. The second partition wall portion 60 defines a first filling chamber S1 adjacent to the first communicating portion 40 and a second filling chamber S2 adjacent to the discharge portion 50 in the gas-filled chamber S20. The first filling chamber S1 is a space surrounded by the second partition wall portion 60 in the gas-filled chamber S20, and is defined by the lower shell 2 and the intermediate shell 3. The second filling chamber S2 is a space outside the second partition wall portion 60 in the gas-filled chamber S20, and is defined by the upper shell 1 and the intermediate shell 3.

[0102] [Second communication portion]

[0103] The second connecting portion 70 is provided in the second partition wall portion 60. The second connecting portion 70 is configured to be closed before the igniter 4 is operated, and to open when the igniter 4 is operated, thereby connecting the first filling chamber S1 with the second filling chamber S2. The second connecting portion 70 is formed as a part of the second partition wall portion 60 in a manner that is cracked when the igniter 4 is operated. In more detail, the second connecting portion 70 is formed by the central portion of the cover wall portion 34 that constitutes the second partition wall portion 60, and protrudes in a dome shape toward the second filling chamber S2 side. Before the igniter 4 is operated, the communication between the first filling chamber S1 and the second filling chamber S2 is cut off. When the igniter 4 is operated, the central portion of the cover wall portion 34 receives the energy generated by the operation of the igniter 4 and cracks, thereby opening the second connecting portion 70, and connecting the first filling chamber S1 with the second filling chamber S2.

[0104] like Figure 1 As shown, in this example, the first communicating portion 40 is disposed opposite to the second communicating portion 70. Therefore, when the igniter 4 is operated, energy (shock wave, high temperature gas, etc.) is discharged from the opened first communicating portion 40 toward the second communicating portion 70, so that the second communicating portion 70 is easily cracked.

[0105] Here, the second communicating portion 70 protrudes toward the second filling chamber S2. That is, the second communicating portion 70 protrudes toward the outside of the first filling chamber S1. Therefore, the strength of the second communicating portion 70 against the energy from the first filling chamber S1 is lower than the strength against the energy from the second filling chamber S2. Therefore, the second communicating portion 70 is also easily cracked when the igniter 4 is operated.

[0106] In addition, the following advantages can be cited as advantages of forming the second connecting portion 70 in a dome shape. When manufacturing the gas generator 100, the pressurized gas is filled into one of the first filling chamber S1 and the second filling chamber S2, and then the pressurized gas is filled into the other. At this time, first, the second connecting portion 70 is deformed into a convex shape toward the other filling chamber side due to the pressure of the pressurized gas filled into the one filling chamber, and then the second connecting portion 70 is pushed back by the pressure of the pressurized gas filled into the other filling chamber and deformed into a convex shape toward the one filling chamber side. If the concave-convex deformation is repeated, it is not preferable from the viewpoint of strength against the pressurized gas. In contrast, in this example, the second connecting portion 70 is formed in advance into a dome shape protruding toward the second filling chamber S2 side, so that the second connecting portion 70 is not easily deformed due to the pressure increase in the second filling chamber S2. Therefore, when the pressurized gas is first filled into the first filling chamber S1, it is necessary not to mention that even when the pressurized gas is first filled into the second filling chamber S2, the second communicating portion 70 is suppressed from deforming into a convex shape toward the first filling chamber S1. That is, at least the convex deformation toward the first filling chamber S1 is suppressed. Therefore, by forming the second communicating portion 70 into a dome shape, it is prevented that the second communicating portion 70 is repeatedly deformed into a concave and convex shape when the pressurized gas is filled.

[0107] Furthermore, the second communicating portion 70 is formed to be thinner than other portions of the second partition wall portion 60 (i.e., portions of the second partition wall portion 60 other than the second communicating portion 70). Therefore, the second communicating portion 70 is weaker than other portions of the second partition wall portion 60. Thus, the second communicating portion 70 is also easily cracked when the igniter 4 is operated.

[0108] Here, Figure 2 It is a diagram for explaining the second communicating portion 70 according to the embodiment. Figure 2 The middle figure shows the upper end surface of the cover wall portion 34 of the intermediate shell 3. Figure 2 As shown in FIG. 1 , a plurality of V-shaped (triangular in cross section) grooves G1 extending linearly are formed in the second communication portion 70. The plurality of grooves G1 extend radially from the central portion of the top of the cover wall portion 34 as a starting point. Figure 2 As shown, in this example, eight grooves G1 are formed at equal angles. However, the technology disclosed in the present invention is not limited thereto. In addition, the shape of the groove G1 is not limited to a V-shape, and may also be a quadrilateral or a semicircular cross section.

[0109] The portion of the second connecting portion 70 where the groove G1 is formed is formed into a linear fragile portion 701 that is thinner than other portions of the second connecting portion 70. The fragile portion 701 is more fragile than other portions (i.e., portions of the second connecting portion 70 other than the fragile portion 701) and is easily broken. The second connecting portion 70 has a linear fragile portion 701 that is easy to crack preferentially, thereby ensuring strength against pressurized gas and being easy to crack when the igniter 4 is working. In this example, a plurality of fragile portions 701 are formed, and all fragile portions 701 intersect in the center of the second connecting portion 70. It should be noted that the strength of the portion where the fragile portions 701 intersect is particularly reduced, so in consideration of the strength against pressurized gas, only a portion of the fragile portions 701 may be intersected, or a scheme in which none of the fragile portions 701 intersects may be adopted. In addition, the intersecting portion of the groove G1 may be formed shallowly. Figure 3 2 is a diagram for explaining a modified example of the second communication portion 70. Figure 3 As shown, in the second connecting portion 70 of the modified example, the fragile portion 701 does not cross at the central portion thereof. That is, the fragile portion 701 is formed at a portion other than the central portion (top portion) of the second connecting portion 70. It should be noted that Figure 2 and Figure 3 The second connecting portion 70 shown has multiple (eight) fragile portions 701, but the fragile portion 701 may not be multiple, but may be one. In addition, the fragile portion 701 of this example is formed as a continuous solid line, but the fragile portion 701 may also be formed as a discontinuously extending dashed line or dotted line.

[0110] like Figure 1 As shown, in this example, the second communication portion 70 is disposed opposite to the discharge portion 50. Therefore, when the igniter 4 is operated, energy (shock wave, high temperature gas, etc.) is discharged from the opened second communication portion 70 toward the second rupture plate 7, so that the second rupture plate 7 is easily ruptured.

[0111] [First filling chamber]

[0112] 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 via the first partition wall portion 30, and is arranged on the upper side of the ignition chamber S10. The first axial region S11 is sandwiched axially by the first connecting portion 40 and the second connecting portion 70. The first radial region S12 is formed in a cylindrical shape in a manner of radially surrounding the ignition chamber S10 via the first partition wall portion 30, and is arranged radially outside the ignition chamber S10.

[0113] [Second filling chamber]

[0114] 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 via the second partition wall portion 60, and is arranged on the upper side of the first axial region S11. The second axial region S21 is sandwiched between the second connecting portion 70 and the discharge portion 50 from the axial direction. The second radial region S22 is formed in a cylindrical shape in a manner of radially surrounding the first radial region S12 of the first filling chamber S1 via the second partition wall portion 60, and is arranged radially outside the first radial region S12.

[0115] [gas]

[0116] The second filling chamber S2 is filled with a hydrogen gas in a compressed state as a fuel gas. However, the fuel gas disclosed herein is not limited to hydrogen. The fuel gas is not particularly limited, but examples thereof include combustible gases such as hydrogen, methane, ethane, propane, butane, and mixed gases containing at least one of these gases.

[0117] In addition, the first filling chamber S1 is filled with a single gas of oxygen in a compressed state as an oxidizing gas. However, the oxidizing gas disclosed herein is not limited to oxygen. The oxidizing gas is not particularly limited, but examples thereof include single gas such as oxygen, nitrous oxide, and a mixed gas such as air and other combustion-supporting gases.

[0118] It should be noted that, in the gas generator of the present disclosure, the fuel gas may be filled in the first filling chamber and the oxidizing gas may be filled in the second filling chamber. That is, in the gas generator of the present disclosure, one of the first filling chamber and the second filling chamber may be filled with the fuel gas and the other may be filled with the oxidizing gas. In addition, the gas filled in the filling chamber may not be in a pressurized state.

[0119] Furthermore, the fuel gas and the inert gas may be filled together in one of the first filling chamber and the second filling chamber. Furthermore, the oxidizing gas and the inert gas may be filled together in the other of the first filling chamber and the second filling chamber. That is, in the case of this example, the second filling chamber S2 may be filled with hydrogen and the inert gas, and the first filling chamber S1 may be filled with oxygen and the inert gas. By allowing the fuel gas, the oxidizing gas and the inert gas to coexist, the combustion temperature of the mixed gas can be reduced and controlled. It should be noted that the pressurized state of the filling chamber can also be formed by the inert gas. The inert gas is not particularly limited, but for example, gases with low reactivity such as nitrogen, argon, helium, and carbon dioxide can be exemplified.

[0120] [Hydrogen embrittlement resistant film]

[0121] Here, in order to prevent hydrogen embrittlement caused by the metal surface constituting the wall surface contacting with hydrogen, a hydrogen embrittlement resistant film C1 formed of a material having hydrogen barrier properties is coated on the wall surface of the second filling chamber S2 filled with hydrogen. The hydrogen embrittlement resistant film C1 is provided on the surface defining the second filling chamber S2 in the upper shell 1 and the intermediate shell 3. The hydrogen embrittlement resistant film C1 is configured to suppress the intrusion of hydrogen into the metal surface. The material of the hydrogen embrittlement resistant film C1 is not limited to a material having hydrogen barrier properties, and may be a resin material, a metal material, or a ceramic material.

[0122] As the resin material forming the hydrogen embrittlement resistant film C1, ethylene-vinyl alcohol copolymer resin, polyamide 6, etc. can be exemplified, as the metal material, A6061-T6 aluminum alloy, etc. can be exemplified, as the ceramic material, aluminum oxide, titanium oxide, etc. can be exemplified. As specific examples of the composition of the hydrogen embrittlement resistant film C1, the Al-5Mg sprayed film described in Japanese Patent Publication No. 2018-141214, the coating with a high hydrogen barrier rate described in Table 1 of Japanese Patent Publication No. 2021-139034, and the ceramic film described in Japanese Patent Publication No. 2007-9276 can be exemplified.

[0123] It should be noted that, in this example, the hydrogen embrittlement resistant film C1 is applied to the wall surface of the second filling chamber S2, but when hydrogen is filled into the first filling chamber S1, the hydrogen embrittlement resistant film C1 is applied to the wall surface of the first filling chamber S1. That is, the hydrogen embrittlement resistant film C1 can be applied to the wall surface of the first filling chamber S1 and the second filling chamber S2 that is filled with hydrogen. However, in the gas generator disclosed in the present invention, the hydrogen embrittlement resistant film is not an essential component.

[0124] [Diffuser housing]

[0125] The diffuser housing 8 is formed into a bottomed cylindrical shape extending vertically and having an upper end blocked. More specifically, the diffuser housing 8 has a cylindrical peripheral wall portion 81 extending vertically and a cover wall portion 82 blocking the upper end of the peripheral wall portion 81. The lower end of the peripheral wall portion 81 (equivalent to one end of the diffuser housing of the present disclosure) is joined to the outer housing 10 in such a manner that the discharge portion 50 of the outer housing 10 is located inside the peripheral wall portion 81. Thus, a diffusion chamber S30 is formed inside the diffuser housing 8, which is connected to the gas filling chamber S20 via the discharge portion 50.

[0126] A plurality of gas discharge holes 83 are formed on the peripheral wall portion 81 of the diffuser housing 8 to connect the diffusion chamber S30 with the outside of the gas generator 100. When the igniter 4 is operated, the working gas from the gas filling chamber S20 passes through the diffusion chamber S30 and is discharged to the outside through the gas discharge holes 83. It should be noted that the number of the gas discharge holes 83 is not particularly limited and may not be multiple.

[0127] [Filter]

[0128] The filter 9 is a cylindrical member extending up and down and having both ends open, and is arranged between the discharge portion 50 and the gas discharge hole 83 in the diffusion chamber S30 in a state where the upper end is supported by the cover wall portion 82 of the diffuser housing 8 and the lower end is supported by the top plate portion 12 of the upper shell 1. The filter 9 is formed with multiple holes in a manner that allows filtering and cooling of the working gas.

[0129] [Arrangement of igniter, communication portion, and discharge portion]

[0130] like Figure 1 As shown, 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 multiple components "arranged on the same straight line" means that there may be a straight line passing through the multiple components. In this example, as the same straight line, the central axis A1 of the housing case 10 passes through the igniter 4, the first communicating portion 40, the second communicating portion 70, and the discharge portion 50. That is, 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.

[0131] The igniter 4, the first connecting portion 40, the second connecting portion 70 and the discharge portion 50 are arranged on the same straight line, which means that the first connecting portion 40, the second connecting portion 70 and the discharge portion 50 are arranged in a straight line in the direction (in this case, upward) in which the combustion products are discharged from the discharge portion 411 of the igniter 4. Therefore, when the igniter 4 is working, it is easy to open the first connecting portion 40, the second connecting portion 70 and the discharge portion 50 together by the energy (shock wave, flame, high-temperature gas, etc.) discharged from the igniter 4. That is, it is easy to open all the first connecting portion 40, the second connecting portion 70 and the discharge portion 50 by one igniter. In addition, the path from the igniter 4 to the diffusion chamber S30 is linear, so the combustion products discharged from the igniter 4 easily reach the diffusion chamber S30, thereby igniting the mixed gas in the diffusion chamber S30 easily. Furthermore, in gas generator 100 of the present embodiment, igniter 4 , first communicating portion 40 , second communicating portion 70 , and discharge portion 50 are arranged close to each other in the axial direction (vertical direction), and therefore, it is easier to open all of them.

[0132] 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 housing case 10, the gas generator 100 can adopt an axisymmetric structure with the central axis A1 as a reference. This facilitates the manufacture of the gas generator 100. Furthermore, by setting the gas generator 100 to an axisymmetric structure, it is possible to suppress uneven output of the gas generator in the circumferential direction.

[0133] [action]

[0134] Next, the operation of the gas generator 100 according to the embodiment will be described. Figure 1 In the state where the gas generator 100 before operation is mounted on a vehicle, a connector (not shown) inserted into the connector insertion space 51 is connected to the conductive portion 42 of the igniter 4, and power can be supplied to the igniter 4. In this state, when a sensor (not shown) mounted on the vehicle senses an impact, power from an external power source (not shown) is supplied to the conductive portion 42 via the connector, whereby the igniter 4 is operated and the explosive in the ignition portion 41 is burned.

[0135] Figure 4 It is a cross-sectional view showing a state of gas generator 100 according to the embodiment when it is operating. Figure 4 1 shows a cross section along the axial direction of the housing shell 10. When the igniter 4 is working, the internal pressure of the ignition part 41 rises as the explosive burns, and the discharge part 411 breaks, and the combustion products of the explosive are discharged into the ignition chamber S10. At this time, the combustion products are discharged upward (axially). The first connecting part 40 is arranged above the igniter 4 and opposite to the discharge part 411 of the igniter 4, so as shown in FIG. Figure 4 As shown, the first rupture plate 6 of the first communication part 40 is cracked by the energy (shock wave, flame, high temperature gas, etc.) discharged from the igniter 4. As a result, the first communication part 40 is opened. In addition, the second communication part 70 is arranged above the first communication part 40 and opposite to the first communication part 40, so the second communication part 70 is cracked by the energy discharged from the first communication part 40 after opening. As a result, the second communication part 70 is opened. Moreover, the discharge part 50 is arranged above the second communication part 70 and opposite to the second communication part 70, so the second rupture plate 7 of the discharge part 50 is cracked by the energy discharged from the second communication part 70 after opening. As a result, the discharge part 50 is opened. In this way, the igniter 4, the first communication part 40, the second communication part 70 and the discharge part 50 are arranged on the same straight line, so they are opened together by the energy discharged from the igniter 4.

[0136] The second connecting portion 70 provided in the second partition wall portion 60 separating the first filling chamber S1 and the second filling chamber S2 is opened, thereby enabling the oxygen (oxidizing gas) filled in the first filling chamber S1 and the hydrogen (fuel gas) filled in the second filling chamber S2 to mix. Oxygen flows into the diffusion chamber S30 through the second connecting portion 70 and the discharge portion 50 and diffuses. Hydrogen flows into the diffusion chamber S30 through the discharge portion 50 and diffuses. Thus, oxygen and hydrogen are mixed in the diffusion chamber S30. Furthermore, the combustion product discharged from the igniter 4 flows into the diffusion chamber S30 through the first connecting portion 40, the second connecting portion 70 and the discharge portion 50, thereby the mixed gas of hydrogen and oxygen is ignited and burns. Thus, water vapor is generated as the working gas for the airbag.

[0137] The working gas generated in the diffusion chamber S30 passes through the filter 9 and is discharged from the gas discharge hole 83 to the outside of the gas generator 100. In the process of the working gas passing through the filter 9, the fragments of the first rupture plate 6, the second rupture plate 7 and the cover wall portion 34 included in the gas are captured by the filter 9. In addition, the working gas is cooled and filtered by the filter 9 when passing through the filter 9. In addition, the gas discharge hole 83 is formed in the peripheral wall portion 81 of the diffuser housing 8, so that the working gas is discharged radially outward. Therefore, the axial flow of the gas from the gas filling chamber S20 to the diffusion chamber S30 is changed to the radial direction through the diffuser housing 8.

[0138] The operating gas exhausted from the gas generator 100 is supplied to the airbag, whereby the airbag is inflated to protect the occupant of the vehicle from impact.

[0139] [Function / Effect]

[0140] As described above, the gas generator 100 of the present embodiment includes:

[0141] Housing shell 10;

[0142] An ignition unit 20, including an igniter 4 that discharges combustion products by operating;

[0143] The first partition wall portion 30 defines an ignition chamber S10 for accommodating the ignition unit 20 and a gas filling chamber S20 for gas filling inside the housing shell 10;

[0144] The first communication portion 40 is provided in the first partition wall portion 30, is closed before the igniter 4 is operated, and is opened by the operation of the igniter 4, thereby connecting the ignition chamber S10 with the gas filling chamber S20;

[0145] The discharge portion 50 is provided in the outer shell 10, is closed before the igniter 4 is operated, and is opened by the operation of the igniter 4, thereby connecting the gas filling chamber S20 with the outside of the outer shell 10;

[0146] The second partition wall portion 60 defines a first filling chamber S1 adjacent to the first communicating portion 40 and a second filling chamber S2 adjacent to the discharge portion 50 in the gas filling chamber S20;

[0147] Hydrogen gas as the fuel gas is filled in one of the first filling chamber S1 and the second filling chamber S2 (the second filling chamber S2 in this example);

[0148] Oxygen gas as an oxidizing gas is filled in the other of the first filling chamber S1 and the second filling chamber S2 (the first filling chamber S1 in this example); and

[0149] The second communicating portion 70 is provided in the second partition wall portion 60 , is closed before the igniter 4 is operated, and is opened by the operation of the igniter 4 , thereby communicating the first filling chamber S1 with the second filling chamber S2 .

[0150] That is, the gas generator 100 adopts a structure in which the second connecting portion 70 provided in the second partition wall portion 60 separating the first filling chamber S1 and the second filling chamber S2 is opened by the operation of the igniter 4, thereby mixing the fuel gas and the oxidizing gas. Thus, the fuel gas and the oxidizing gas can be mixed by the single igniter 4. Therefore, compared with a gas generator having a structure in which different containers connected to a common chamber are filled with gas, and each container is opened by a different igniter, thereby mixing the gas in the chamber, the gas generator 100 of this embodiment can reduce the number of parts and simplify the structure.

[0151] Furthermore, in the gas generator 100 of the present embodiment, the igniter 4 is disposed opposite to the first communicating portion 40. Thus, when the igniter 4 is operated, energy can be discharged from the igniter 4 toward the first communicating portion 40, and the first communicating portion 40 can be easily opened.

[0152] In gas generator 100 of the present embodiment, first communicating portion 40 and second communicating portion 70 are disposed opposite to each other. Thus, when igniter 4 is operated, energy can be discharged from opened first communicating portion 40 toward second communicating portion 70, and second communicating portion 70 can be easily opened.

[0153] Furthermore, in the gas generator 100 of the present embodiment, the second communicating portion 70 is disposed opposite to the discharge portion 50. Thus, when the igniter 4 is operated, energy can be discharged from the opened second communicating portion 70 toward the discharge portion 50, and the discharge portion 50 can be easily opened.

[0154] In the gas generator 100 of the present embodiment, 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. Therefore, when the igniter 4 is operated, the energy discharged from the igniter 4 can easily open the first communicating portion 40, the second communicating portion 70, and the discharge portion 50.

[0155] Furthermore, the housing case 10 of the present embodiment is formed into a bottomed cylindrical shape, and the igniter 4, the first connecting portion 40, the second connecting portion 70, and the discharge portion 50 are arranged on the central axis A1 of the housing case 10. Thus, the gas generator 100 can be set to an axisymmetric structure with the central axis A1 as a reference, which can make the manufacture of the gas generator 100 easy and suppress the output unevenness of the gas generator 100 in the circumferential direction.

[0156] However, in the gas generator of the present disclosure, the arrangement of the igniter, the first communicating portion, the second communicating portion, and the discharge portion is not limited to the above-described arrangement, and may not be arranged in a straight line.

[0157] In addition, the gas generator 100 of the present embodiment also includes a cylindrical diffuser shell 8, one end of which is joined to the outer shell 10 in such a manner that a diffusion chamber S30 connected to the gas filling chamber S20 via a discharge portion 50 is formed inside the diffuser shell 8, and a gas discharge hole 83 is formed on the peripheral wall portion 81 of the diffuser shell 8 to connect the diffusion chamber S30 with the outside of the gas generator 100. Thus, the fuel gas and the oxidizing gas can be mixed and ignited in the diffusion chamber S30. In addition, the gas discharge hole 83 is formed on the peripheral wall portion 81 of the diffuser shell 8, so that the flow of the gas can be changed from the axial direction to the radial direction. It should be noted that the diffuser shell 8 is not a necessary structure in the gas generator disclosed in the present invention. The gas generator disclosed in the present invention can be configured to mix and ignite the gas in the filling chamber.

[0158] In addition, the fuel gas filled in the gas generator 100 of the present embodiment is hydrogen gas, and the wall surface of the side filled with hydrogen gas (the second filling chamber S2 in this example) of the first filling chamber S1 and the second filling chamber S2 is coated with a hydrogen embrittlement resistant film C1. Thus, hydrogen embrittlement caused by the metal surface constituting the wall surface of the second filling chamber S2 contacting with hydrogen can be prevented.

[0159] In addition, the second connecting portion 70 of the present embodiment is formed as a part of the second partition wall portion 60 in a manner that is ruptured by the operation of the igniter 4, and protrudes in a dome shape toward the second filling chamber S2. As a result, at least convex deformation toward the first filling chamber S1 is suppressed, so that the second connecting portion 70 is prevented from repeatedly deforming in a concave and convex manner when the pressurized gas is filled. As a result, the strength of the second connecting portion 70 against the pressurized gas can be improved.

[0160] Furthermore, the second communicating portion 70 of the present embodiment is formed to be thinner than other portions of the second partition wall portion 60. Thus, when the igniter 4 is operated, the second communicating portion 70 is easily broken.

[0161] Furthermore, the second communicating portion 70 has a linear fragile portion 701 formed thinner than other portions of the second communicating portion 70. Thus, when the igniter 4 is operated, the second communicating portion 70 is more likely to break.

[0162] It should be noted that the second communication portion of the gas generator disclosed herein may not be a part of the second partition wall portion. The second communication portion may also be formed by an opening portion and a rupture plate, wherein the opening portion is formed in the second partition wall portion, the rupture plate blocks the opening portion before the igniter operates, and is ruptured by the operation of the igniter.

[0163] In addition, the first communication portion 40 of the present embodiment is formed by the opening portion 24 and the first rupture plate 6, the opening portion 24 is formed in the first partition wall portion 30, the first rupture plate 6 blocks the opening portion 24 before the igniter 4 is operated, and is ruptured by the operation of the igniter 4. Thus, the first communication portion 40 can be opened by the operation of the igniter 4. It should be noted that the first communication portion of the present disclosure is not limited to the above-mentioned scheme, for example, it can also be formed as a part of the first partition wall portion in a manner that is ruptured by the operation of the igniter.

[0164] In addition, the discharge portion 50 of the present embodiment is formed by the opening portion 14 formed in the outer shell 10 and the second rupture plate 7, which blocks the opening portion 14 before the igniter 4 is operated and is ruptured by the operation of the igniter 4. Thus, the discharge portion 50 can be opened by the operation of the igniter 4. It should be noted that the discharge portion of the present disclosure is not limited to the above-mentioned scheme, and for example, it can also be formed as a part of the outer shell in a manner that is ruptured by the operation of the igniter.

[0165] It should be noted that the ignition unit of the present disclosure may also include a gas generator, which is arranged in the ignition chamber and burns by the operation of the igniter. By such an arrangement, the energy generated by the operation of the igniter can be increased. That is, the energy used to open the first connecting part, the second connecting part, and the discharge part can be increased. For example, in the case where the igniter, the first connecting part, the second connecting part, and the discharge part are not arranged on the same straight line and the energy discharged from the igniter alone is insufficient, the energy can be supplemented by arranging a gas generator in the ignition chamber.

[0166] In addition, the first filling chamber S1 of the present embodiment has a first axial region S11, which is a region adjacent to the ignition chamber S10 in the axial direction of the housing shell 10 via the first partition wall portion 30, and a cylindrical first radial region S12, which is a region surrounding the ignition chamber S10 from the radial direction of the housing shell 10 via the first partition wall portion 30. Furthermore, the second filling chamber S2 of the present embodiment has a second axial region S21, which is a region adjacent to the first axial region S11 of the first filling chamber S1 in the axial direction of the housing shell 10 via the second partition wall portion 60, and a cylindrical second radial region S22, which is a region surrounding the first radial region S12 of the first filling chamber S1 from the radial direction of the housing shell 10 via the second partition wall portion 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. In addition, the ignition chamber S10, the first radial region S12, and the second radial region S22 are arranged in order from the radial inside to the outside. The first filling chamber S1 has a cylindrical first radial region S12, thereby shortening the length of the first filling chamber S1 in the axial direction while ensuring the volume for filling the gas. Similarly, the second filling chamber S2 has a cylindrical second radial region S22, thereby shortening the length of the second filling chamber S2 in the axial direction while ensuring the volume for filling the gas. As a result, the length of the gas generator 100 in the axial direction can be shortened and the gas generator 100 can be miniaturized. In addition, in the gas generator 100 of the embodiment, the first connecting portion 40, the second connecting portion 70, and the discharge portion 50 are arranged on the central axis A1 of the housing shell 10, so by shortening the axial length of the first filling chamber S1 and the second filling chamber S2, the distance between the first connecting portion 40 and the second connecting portion 70 and the distance between the second connecting portion 70 and the discharge portion 50 can be shortened. Thus, when the igniter 4 is operated, the second communicating portion 70 and the discharge portion 50 can be easily opened.

[0167] Here, if Figure 1 As shown in the figure, the housing container composed of the housing case 10 and the diffuser case 8 is set as the gas generator case 80. In addition, the length of the gas generator case 80 in the axial direction is set to L1, and the width of the gas generator case 80 in the radial direction is set to W1. The gas generator case 80 of the gas generator 100 of the present embodiment is formed into a short-sized cylindrical shape so that the length L1 in the axial direction is shorter than the width W1 in the radial direction. As a result, the gas generator 100 can be miniaturized.

[0168] <Others>

[0169] As mentioned above, although the embodiment of the technology of this disclosure is described, each scheme disclosed in this specification can also be combined with other arbitrary features disclosed in this specification.

[0170] Description of Reference Numerals

[0171] 4: Ignition;

[0172] 6: first rupture plate;

[0173] 7: Second rupture plate;

[0174] 8: Diffuser housing;

[0175] 10: Shell;

[0176] 20: ignition unit;

[0177] 30: first partition wall portion;

[0178] 40: first connecting portion;

[0179] 50: discharge part;

[0180] 60: second partition wall portion;

[0181] 70: second connecting portion;

[0182] 80: Gas generator housing;

[0183] 100: Gas generator;

[0184] C1: Hydrogen embrittlement resistant film;

[0185] S1: first filling chamber;

[0186] S2: second filling chamber;

[0187] S10: ignition chamber;

[0188] S20: Gas filling chamber.

Claims

1. A gas generator, comprising: housing shell; an ignition unit, including an igniter operable to discharge combustion products; A first partition wall portion defines an ignition chamber for accommodating the ignition unit and a gas filling chamber for gas filling inside the housing shell; a first communication portion, provided at the first partition wall portion, which is closed before the igniter is operated and is opened by the operation of the igniter, thereby connecting the ignition chamber with the filling chamber; a discharge portion, provided in the outer shell, which is closed before the igniter is operated and is opened by the operation of the igniter, thereby connecting the gas-filled chamber with the outside of the outer shell; a second partition wall portion defining a first filling chamber adjacent to the first communicating portion and a second filling chamber adjacent to the discharge portion within 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; and The second communication portion is provided in the second partition wall portion, is closed before the igniter is operated, and is opened by the operation of the igniter, thereby communicating the first filling chamber with the second filling chamber.

2. The gas generator according to claim 1, wherein: The igniter is arranged to face the first communication portion.

3. The gas generator according to claim 1 or 2, wherein: The first communicating portion and the second communicating portion are arranged to face each other.

4. The gas generator according to claim 1 or 2, wherein: The second communication portion is arranged to face the discharge portion.

5. The gas generator according to claim 1, wherein: The igniter, the first communicating portion, the second communicating portion, and the discharge portion are arranged on the same straight line.

6. The gas generator according to claim 5, wherein: The outer shell is formed into a bottomed cylindrical shape. The igniter, the first communicating portion, the second communicating portion, and the discharge portion are arranged on a central axis of the outer shell.

7. The gas generator according to claim 1 or 2, wherein: The gas generator further includes a cylindrical diffuser housing, one end of which is joined to the outer shell in such a manner that a diffusion chamber communicating with the gas filling chamber via the discharge portion is formed inside the diffuser housing. A gas discharge hole that connects the diffusion chamber with the outside of the gas generator is formed in a peripheral wall portion of the diffuser housing.

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

9. The gas generator according to claim 1 or 2, wherein: The fuel gas is hydrogen.

10. The gas generator according to claim 9, wherein: A hydrogen embrittlement-resistant film is applied to a wall surface of one of the first filling chamber and the second filling chamber that is filled with the hydrogen gas.

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

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

13. The gas generator according to claim 12, wherein: The second communicating portion is formed to be thinner than other portions of the second partition wall portion.

14. The gas generator according to claim 13, wherein: The second communicating portion has a linear fragile portion, and the fragile portion is formed to be thinner than other portions of the second communicating portion.

15. The gas generator according to claim 1 or 2, wherein: The ignition unit includes a gas generating agent, which is disposed in the ignition chamber and combusts when the igniter is operated.

16. The gas generator according to claim 1 or 2, wherein: The first communication portion is formed of an opening portion formed in the first partition wall portion and a rupture plate, the opening portion being closed before the igniter is operated and being ruptured by the operation of the igniter.

17. The gas generator according to claim 1 or 2, wherein: The discharge portion is formed of an opening portion formed in the housing case and a rupture plate, the opening portion being closed before the igniter is operated and being ruptured by the operation of the igniter.

18. The gas generator according to claim 1 or 2, wherein: The outer shell is formed into a bottomed cylindrical shape. The first filling chamber has a first axial region and a cylindrical first radial region, the first axial region is a region adjacent to the ignition chamber in the axial direction of the outer shell body through the first partition wall portion, and the first radial region is a region surrounding the ignition chamber from the radial direction of the outer shell body through the first partition wall portion. The second filling chamber has a second axial region and a cylindrical second radial region, the second axial region is a region adjacent to the first axial region of the first filling chamber in the axial direction of the outer shell body via the second partition wall portion, and the second radial region is a region surrounding the first radial region of the first filling chamber from the radial direction of the outer shell body via the second partition wall portion.

19. The gas generator according to claim 18, wherein: The gas generator further includes a cylindrical diffuser housing, one end of which is joined to the outer shell in such a manner that a diffusion chamber communicating with the gas filling chamber via the discharge portion is formed inside the diffuser housing. A gas discharge hole is formed on a peripheral wall portion of the diffuser housing to connect the diffusion chamber with the outside of the gas generator. The diffusion chamber is adjacent to the gas-filled chamber in the axial direction of the outer shell via a wall of the outer shell. The gas generator housing formed by the outer shell and the diffuser shell has an axial length that is shorter than a radial width.

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