Gas-Generator

Abstract

The present invention provides a gas generator which includes: an ignition device positioned at a first end of a cylindrical housing main body section, a diffuser section provided with a gas delivery port and closing off a second end of the same, which is axially opposite the first end; a combustion chamber located in an interior space of the cylindrical housing main body section; a cup-shaped element that divides the combustion chamber and the diffuser section, a bottom surface and an opening of the cup-shaped element, each located on the side of the first end and the second end of the cylindrical housing main body section, and a first gap formed between the circumferential wall of the cup-shaped element and an inner wall surface of the cylindrical housing main body section; The cylindrical filter is positioned in a space surrounded by the cup-shaped element and the diffuser section, and A first end surface of the cylindrical filter is in contact with the bottom surface of the cup-shaped element, and a second end surface of the same, on the opposite side, is in contact with a closed end surface of the diffuser section; and The connecting hole of the cup-shaped element is formed in a position closer to the first end face of the cylindrical filter to be facing the first gap, and the gas discharge port of the diffuser section is closer to the second end face of the cylindrical filter.

Description

[0001] The present invention relates to a gas generator according to the preamble of independent patent claim 1 and a gas generator according to the preamble of independent patent claim 3. Such a gas generator is known from German patent application DE 10 2007 019 755 A1.

[0002] German patent application DE 11 2015 002 937 T5 discloses a gas generator comprising a cylindrical housing in which an ignition device and a diffuser section with a gas outlet connection are arranged. An inner cylindrical element is arranged to form a gap with an inner circumferential wall surface of the cylindrical housing. A gas-generating agent is filled into the inner cylindrical element, the gap serving as a gas outlet path leading to the gas outlet connection. The inner cylindrical element is formed from a plurality of cylindrical elements connected axially in connecting sections, each cylindrical element having a circumferential wall with a plurality of gas inlet / outlet openings.An opening of each of the plurality of cylindrical elements, serving as a connecting section of the corresponding cylindrical elements, is provided with a plurality of concave-convex sections, the concave sections and the convex sections of the corresponding connecting sections being connected to each other in order to join the cylindrical elements.Both axial ends of the connected cylindrical elements have a corresponding projection that extends outwards in the radial direction, wherein an outer circumferential section of a first projection on the side of the ignition device serves as a first contact section and a surface of a second projection on the side of the diffuser section serves as a second contact section, and wherein the connecting sections, the first contact section and the second contact section abut against the inner circumferential wall surface of the cylindrical housing and have an opening or a gap so that a gas can pass through.

[0003] Some gas generators that include a gas generating device as a gas generating source have a filter to filter and cool a combustion gas.

[0004] JP 2014-184427 A discloses an invention of a hybrid gas generator. A structure is disclosed in which a filter 60 is provided in the vicinity of a gas outlet within a pressure housing 22, filled with a pressurized gas, and in the vicinity of a diffuser section 150, which serves as a gas delivery port.

[0005] In Fig. The filter 60 is held and fixed between a cup-shaped element 170 and a porous plate element 180. A connecting hole 173, for introducing a gas, is formed in a circumferential wall of the cup-shaped element 170. The perforated plate element 180 has a large number of connecting holes 183. A gas enters the filter 60 from an outer circumferential surface, via the connecting holes 173, and is then discharged from an end surface (a first end surface) 61.

[0006] US 6,474,685 B1 discloses an invention of a pyrotechnic gas generator. A combustion chamber 21, filled with a gas-generating agent 25, is separated from a filter chamber 29, which accommodates a filter 71, by a wall 33, which is provided with an opening 37.

[0007] It is disclosed that an essentially cone-shaped filter 42 is positioned in the combustion chamber 21, and a combustion gas flows in from an inclined surface of the cone shape, passes through the opening 37 of the wall 33, enters the filter chamber 29, and is discharged through the filter 71 in a radial direction.

[0008] JP 2007-131254 A discloses an invention of a pyrotechnic gas generator. The gas generator according to JP 2007-131254 A has ring filters 13a and 13b at two locations, and it is described that the following advantageous effects are achieved thereby: “After passing through the filters 13a and 13b, the combustion gas flows again from the opposite surface of the filters. Accordingly, the combustion gas passes through a single filter twice and continues to strike the inner wall surface of the housing to cause combustion residues to be collected, thereby improving the collection efficiency of combustion residues.” (Paragraph 0045).

[0009] The object of the present invention is to provide a gas generator that exhibits improved cooling and filtration effects with a simple and lightweight structure. This object is achieved according to the invention by a gas generator having the features of independent claim 1. Furthermore, this object is achieved according to the invention by a gas generator having the features of independent claim 3. Preferred embodiments are set forth in the dependent claims.

[0010] Exemplary embodiment 1 of the present invention (hereinafter referred to as "exemplarity 1") is a gas generator comprising: a cylindrical housing comprising a cylindrical housing main body section and a diffuser section; an ignition device positioned at a first end of the cylindrical housing main body section, the diffuser section being provided with a gas discharge port and closing off a second end of the same on an axial opposite side of the first end; A combustion chamber, which accommodates a gas-generating means, is present in an interior of the cylindrical housing main body section; a cup-shaped element that divides the combustion chamber and the diffuser section, The cup-shaped element has a base, a perimeter wall which has a connecting hole, and an opening; the cup-shaped element is positioned such that, the bottom surface is located on the side of the first end of the cylindrical housing main body section, the opening is arranged on the side of the second end of the same, and the circumferential wall extends radially outwards opposite an inner wall surface of the cylindrical housing main body section in order to form a first gap between them, which connects the combustion chamber with the diffuser section, a cylindrical filter positioned in a space surrounded by the cup-shaped element and the diffuser section, The cylindrical filter is positioned such that a first end face of the same is in contact with the bottom surface of the cup-shaped element, a second end face of the same is on the opposite side to the first end face in contact with a closed end face of the diffuser section, and a central axis of the cylindrical filter is aligned with a long-axis direction of the cylindrical housing, and The connecting hole of the cup-shaped element is formed in a position closer to the first end face of the cylindrical filter in order to be facing the first gap, and the gas discharge port of the diffuser section is formed closer to the second end face of the cylindrical filter.

[0011] Exemplary embodiment 2 of the present invention (hereinafter referred to as "exemplarity 1") is a gas generator comprising: a cylindrical housing comprising a cylindrical housing main body section and a diffuser section; an ignition device positioned at a first end of the cylindrical housing main body section, a diffuser section is provided with a gas discharge port and closes a second end of the same on an axial opposite side to the first end; a combustion chamber which includes a gas generating means which is present in an interior of the cylindrical housing main body section; a cup-shaped element that divides the combustion chamber and the diffuser section, The cup-shaped element has a base, a perimeter wall which has a connecting hole, and an opening; the cup-shaped element is positioned such that, the bottom surface is located on the side of the first end of the cylindrical housing main body section, the opening is located on the side of the second end of the same, and the circumferential wall extends radially outwards against an inner wall surface of the cylindrical housing main body section to form a first gap between them, connecting the combustion chamber to the diffuser section, a cup-shaped filter having a base, a perimeter wall and an opening, and positioned in a space surrounded by the cup-shaped element and the diffuser section, The cup-shaped filter is positioned so that the bottom surface of the cup-shaped filter is in contact with the bottom surface of the cup-shaped element, an end surface of the opening of the cup-shaped filter is in contact with a closed end surface of the diffuser section, and a central axis of the cup-shaped filter is aligned with a long-axis direction of the cylindrical housing. The connecting hole of the cup-shaped element is formed in a position closer to the bottom surface of the cup-shaped filter in order to be facing the first gap, and the gas discharge port of the diffuser section is formed closer to the opening of the cup-shaped filter. Description of the drawings

[0012] The present invention will be further explained by the detailed description given below and the accompanying drawings, which are only given by way of illustration and are therefore not limiting to the invention, wherein: Fig. Figure 1 is a cross-sectional view in one direction from an axis X of a gas generator according to the present invention; Fig. Figure 2 shows, in (a), a cross-sectional view of a cup-shaped element that is in Fig. 1 is used, and in (b) to (e) cross-sectional views of cup-shaped elements in other shapes; Fig. Figure 3 shows a partial cross-sectional view in one direction along the X axis of a gas generator, in which a cylindrical filter, different from the one shown in Figure 3, is located. Fig. 1, is used; Fig. Figure 4 shows, in (a), a partial cross-sectional view in one direction from the X axis of a gas generator in which a cup-shaped filter has a different shape than that shown in Figure 4. Fig. 1, and in (b), a partial cross-sectional view in one direction from the X axis of a gas generator in which a cup-shaped filter has a different shape from that shown in (a); and Fig. Figure 5 shows, in (a), a partial cross-sectional view of an embodiment in which a diameter expansion prevention element is incorporated in the gas generator shown in Fig. 1, is positioned, and in (b) and (c), partial cross-sectional views of embodiments in which a diameter expansion prevention element is positioned differently from that shown in (a). Detailed description of the invention

[0013] Since the gas generator is a hybrid type according to JP 2014-184427 A, a breakable plate (a second breakable plate) 58 is necessary, and if the filter is positioned inside the pressurized gas chamber housing, a filter holding structure, as described above, is required. Therefore, the structure is complex, and there is room for improvement in terms of simplification.

[0014] Because many filters and parts are used in US 6 474 685 B1, the structure is complicated and not suitable for achieving weight reduction.

[0015] To achieve the advantageous effect described in paragraph 0045 of JP 2007-131254 A, the filters must be positioned in two locations; a combination of a cylindrical partition wall 19 and a cylindrical partition wall 18 is necessary. Furthermore, with the ring filters 13a and 13b, a cooling effect of the combustion gas is insufficient because the combustion gas passes through a narrow area of ​​the respective filters twice.

[0016] The present invention provides a gas generator with a simple and lightweight structure that exhibits improved cooling and filtering effects.

[0017] A cylindrical housing used in the present invention is made of a metal such as iron or stainless steel and comprises a cylindrical housing main body section and a diffuser section. The cylindrical housing main body section and the diffuser section can be joined together by welding or can be integrally cast beforehand.

[0018] An electric igniter used in a known gas generator, or a combination of an electric igniter and a transfer charge, can be used as an ignition device. A known gas-generating agent, black powder, or the like can be used as the transfer charge.

[0019] A gas outlet of the diffuser section is formed in multiple circumferential walls of the cylindrical housing (the diffuser section) and sealed by a closure element such as a sealing band. The gas generation agent used, which is filled into a combustion chamber, is a gas generation agent used in a known gas generator.

[0020] The combustion chamber and the diffuser section are divided by a cup-shaped element. Here, "divided" means that although a space within the combustion chamber and an interior space within the diffuser section are separated by the cup-shaped element, a gas exhaust passage from the combustion chamber to the diffuser section is ensured. The gas exhaust passage from the combustion chamber to the diffuser section is a gas exhaust passage that includes the combustion chamber, a first gap, a connecting hole, and the diffuser section.

[0021] The cup-shaped element only needs to be positioned to form the first gap between itself and an inner wall surface of the cylindrical housing main body, and this first gap connects the combustion chamber to the diffuser section. For example, the cup-shaped element can be fixed in the following arrangements: (I) An arrangement in which an annular projection (an annular stepped surface) projecting inwards is formed between the cylindrical housing main body section and the diffuser section, and an end face of an opening of the cup-shaped element is in contact with the annular projection (the annular stepped surface); (II) In the arrangement (I), as described above, the use of the cup-shaped element having an enlarged diameter section at the opening results in the enlarged diameter section being in contact with the ring projection (the ring-stepped surface); (III) In the arrangement (I) as described above, using the cup-shaped element in which an outer diameter (d1) of a base surface and an outer diameter (d2) of an opening satisfy a relationship of d2 > d1, and a circumferential wall from the base surface to the opening is an inclined surface, an end surface of the opening rests against the ring projection (the ring-stepped surface); (IV) An arrangement in which an inner diameter (D1) of the cylindrical housing main body and an inner diameter (D2) of the diffuser section satisfy a relationship of D1 > D2 in order to form an annular stepped surface at one boundary thereof, and the opening of the cup-shaped element in the form of (I), (II) or (III) is in contact with the annular stepped surface; (V) An arrangement in which the cup-shaped element has the enlarged-diameter section at the opening and a folded section, folded from the enlarged-diameter section to a bottom surface, the folded section of the cup-shaped element being pressed into an inner wall surface of the cylindrical housing main body section, by setting an outer diameter of the folded section and an inner diameter of the cylindrical housing main body section; and (VI) An arrangement in which the use of the cup-shaped element in which the outer diameter (d1) of the bottom surface and the outer diameter (d2) of the opening satisfy a relationship of d2 > d1, the circumferential wall from the bottom surface to the opening is an inclined surface, and the folded section, folded from the enlarged diameter section to the bottom surface, is further provided, the folded section of the cup-shaped element is pressed into the inner wall surface of the cylindrical housing main body section, by setting an outer diameter of the folded section and an inner diameter of the cylindrical housing main body section.

[0022] As typically described in embodiment 1, in the gas generator according to the present invention, a combustion gas, generated by the combustion of a gas-generating agent within the combustion chamber, passes through the combustion chamber, the first gap, and the area surrounding the first end face of the cylindrical filter via the connecting hole, and then enters the diffuser section. Subsequently, after passing through the area surrounding the second end face of the same cylindrical filter, the combustion gas is discharged from the gas outlet.

[0023] The gas generator according to the present invention, operating in this manner, provides the following advantageous effects (i) to (iii): (i) By causing the combustion gas to pass through the same filter twice, the cooling effect and the filtration effect are improved compared to the case where a combustion gas passes through a filter only once (for example, JP 2014-184427 A and US 6 474 685 B1). The amount of filter and the number of parts are reduced compared to the case where filters are positioned separately in two locations (for example, JP 2007-131254 A). (ii) Furthermore, since the filter is a cylindrical filter and the cylindrical filter is positioned such that a central axis of the same is aligned in one direction with a long axis of the cylindrical housing, the combustion gas passes through the cylindrical filter in a portion closer to the first end at a time of first passage, and the combustion gas passes through the cylindrical filter in a portion closer to the second end at a time of second passage. Therefore, it is likely that the combustion gas will be discharged more rapidly when compared with the embodiment in JP 2007-131254 A. (iii) Furthermore, since the combustion gas more readily comes into contact with an irregular surface of the cylindrical filter, and an area of ​​the irregular surface is large, combustion residues contained in the combustion gas adhere more readily to the cylindrical filter and are more reliably collected by the cylindrical filter, compared with the embodiment in JP 2007-131254 A.

[0024] It is preferred in the gas generator according to embodiment 1 that a circumferential wall of the cylindrical filter includes a thick-walled section on the side of the first end face and a thin-walled section on one side of the second end face, and only the thick-walled section faces the connecting hole of the cup-shaped element.

[0025] The combustion gas, produced by burning the gas-generating agent within the combustion chamber, passes through the combustion chamber, the first gap, and the area surrounding the first end face of the cylindrical filter via the connecting hole, and enters the diffuser section. Accordingly, the combustion gas, having passed through the area surrounding the first end face of the cylindrical filter, always passes through the thick-walled section of the cylindrical filter, thereby improving both the cooling and filtration effects.

[0026] The thicknesses of the thick-walled section and the thin-walled section are not specifically limited, however, for example, the thickness of the thick-walled section to the thickness of the thin-walled section can be in a range of 1.2 to 3.0.

[0027] A gas generator according to embodiment 2 differs from the gas generator according to embodiment 1 in that a cup-shaped filter is used as the filter. The connecting hole of the cup-shaped element can face only one circumferential wall of the cup-shaped filter, or it can face both the circumferential wall and a bottom surface of the cup-shaped filter. The gas generator according to embodiment 2 operates in the same way and produces the same advantageous effects as the gas generator according to embodiment 1.

[0028] In the gas generator according to embodiment 2, it is preferred that the thickness of the bottom surface of the cup-shaped filter is greater than the thickness of the circumferential wall of the cup-shaped filter and greater than the inner diameter of the connecting hole of the cup-shaped element, and only the bottom surface of the cup-shaped filter faces the connecting hole of the cup-shaped element.

[0029] A combustion gas, generated by burning the gas-generating agent within the combustion chamber, passes through the combustion chamber, the first gap, and the base of the cup-shaped filter via the connecting hole, and then enters the diffuser section. As the combustion gas enters the diffuser section in this manner, it passes through the base of the cup-shaped filter, which is thicker than the perimeter wall, thus improving both the cooling and filtration effects.

[0030] It is preferred in the gas generator according to embodiment 1 that the outer diameter of the cup-shaped element at the side of the opening is larger than the outer diameter at the bottom surface of the same. A ring-stepped surface is formed on an inner wall surface of the cylindrical housing main body section on the side of the diffuser section. The end surface of the opening of the cup-shaped element is in contact with the ring-stepped surface, so that the first gap between the circumferential wall and the cup-shaped element is formed, which has a connecting hole and an inner wall surface of the cylindrical housing main body section, and An outer surface of the circumferential wall of the cylindrical filter on the side of the first end surface is in contact with an inner surface of the circumferential wall of the cup-shaped element, which has a connecting hole, and a second gap is formed between the gas discharge port and an outer surface of the circumferential wall of the cylindrical filter, on the side of the second end surface (Exemplary 3).

[0031] Furthermore, it is preferred in the gas generator according to embodiment 2 that the outer diameter of the cup-shaped element at the side of the opening is larger than the outer diameter of its base surface. A ring-stepped surface is formed on an inner wall surface of the cylindrical housing main body section on the side of the diffuser section. The end surface of the opening of the cup-shaped element is in contact with the ring-stepped surface in order to form the first gap between the circumferential wall of the cup-shaped element, which has a connecting hole, and an inner wall surface of the cylindrical housing main body section, and An outer surface of the circumferential wall of the cup-shaped filter, on the side of the bottom surface, is in contact with an inner surface of the circumferential wall of the cup-shaped element, which has a connecting hole, and a second gap is formed between the gas discharge connection and an outer surface of the circumferential wall of the cup-shaped filter on the side of the opening (Exemplary 4).

[0032] In the gas generators according to embodiments 3 and 4, the outer diameter of the cup-shaped element at the opening side is larger than the outer diameter of its base. The cup-shaped elements used in arrangements (II), (III), (V), and (VI), as described above, can serve as such cup-shaped elements.

[0033] The ring-stepped surface can be the ring projection according to arrangement (I) or the ring-stepped surface according to arrangement (IV), as described above.

[0034] In the gas generator according to embodiment 3 or embodiment 4, the dimensions of the cup-shaped element and the ring-stepped surface are adapted such that, when the cylindrical filter or the cup-shaped filter is positioned, a second gap is formed between the gas discharge port and the outer surface of the circumferential wall of the cylindrical filter, on the side of the second end face, or the outer surface of the circumferential wall of the cup-shaped filter, on the side of the opening. With the presence of this second gap, the combustion gas passes through the entire diffuser section, enters the filter facing the second gap, and is then discharged from the gas discharge port, thereby improving the cooling and filtering effect of the filter.

[0035] It is preferred in the gas generator according to embodiment 3 that the outer diameter of the cup-shaped element at the side of the opening is larger than the outer diameter of its base surface. A ring-stepped surface is formed on an inner wall surface of the cylindrical housing main body section on the side of the diffuser section. The end surface of the opening of the cup-shaped element is in contact with the ring-stepped surface in order to form the first gap between the circumferential wall of the cup-shaped element, which has a connecting hole, and an inner wall surface of the cylindrical housing main body section. An outer surface of the circumferential wall of the cylindrical filter on the side of the first end face is in contact with an inner surface of the circumferential wall of the cup-shaped element, which has a connecting hole, and a second gap is formed between the gas discharge port and an outer surface of the circumferential wall of the cylindrical filter on the side of the second end face, and With reference to an area (A1) where the circumferential wall of the cylindrical filter and the circumferential wall of the cup-shaped element are in contact with each other, and an area (A2) where the circumferential wall of the cylindrical filter faces the second gap, A2 is in a range of more than 50% to 80% if the total area of ​​A1 and A2 is 100%.

[0036] It is preferred in the gas generator according to embodiment 4 that the outer diameter of the cup-shaped element at the side of the opening is larger than the outer diameter of its base surface. A ring-stepped surface is formed on an inner wall surface of the cylindrical housing main body section on the side of the diffuser section. The end surface of the opening of the cup-shaped element is in contact with the ring-stepped surface in order to form the first gap between the circumferential wall of the cup-shaped element, which has a connecting hole, and an inner wall surface of the cylindrical housing main body section. An outer surface of the circumferential wall of the cup-shaped filter, on the side of the bottom surface, is in contact with an inner surface of the circumferential wall of the cup-shaped element, which has a connecting hole, and a second gap is formed between the gas discharge port and an outer surface of the circumferential wall of the cup-shaped filter on the side of the opening, and With reference to an area (A1) where the circumferential wall of the cup-shaped filter and the circumferential wall of the cup-shaped element are in contact with each other, and an area (A2) where the circumferential wall of the cup-shaped filter faces the second gap, A2 is in a range of more than 50% to 80% if an entire area of ​​A1 and A2 is 100%.

[0037] If A1 and A2 satisfy the above-mentioned relationship, then, in particular, advantageous effects (ii) and (iii) are more pronounced than the advantageous effects (i) to (iii) described above. If the total range of A1 and A2 is 100%, then a range of A2 is more preferred in the range of 60% to 80% and further preferred in the range of 60% to 75%.

[0038] It is preferred in a gas generator according to embodiment 3 that the outer diameter of the cup-shaped element at the side of the opening is larger than the outer diameter of its base surface. A ring-stepped surface is formed on an inner wall surface of the cylindrical housing main body section on the side of the diffuser section. The end surface of the opening of the cup-shaped element is in contact with the ring-stepped surface to form the first gap between the circumferential wall of the cup-shaped element, which has a connecting hole, and an inner wall surface of the cylindrical housing main body section; an outer surface of the circumferential wall of the cylindrical filter, on the side of the first end surface, is in contact with an inner surface of the circumferential wall of the cup-shaped element, which has a connecting hole; and a second gap is formed between the gas discharge port and an outer surface of the circumferential wall of the cylindrical filter on the side of the second end surface. A diameter expansion prevention element is positioned between the circumferential wall of the cylindrical filter, on the side of the second end face, and an inner circumferential wall surface of the diffuser section, on the side of a closed end face, and the diameter expansion prevention element blocks a diameter expansion on the circumferential wall of the cylindrical filter, on the side of the second end face.

[0039] It is preferred in the gas generator according to embodiment 4 that the outer diameter of the cup-shaped element at the side of the opening is larger than the outer diameter of its base surface. A ring-stepped surface is formed on an inner wall surface of the cylindrical housing main body section on the side of the diffuser section. The end surface of the opening of the cup-shaped element is in contact with the ring-stepped surface in order to form the first gap between the circumferential wall of the cup-shaped element, which has a connecting hole, and an inner wall surface of the cylindrical housing main body section. An outer surface of the circumferential wall of the cup-shaped filter, on the side of the bottom surface, is in contact with an inner surface of the circumferential wall of the cup-shaped element, which has a connecting hole, and a second gap is formed between the gas discharge port and an outer surface of the circumferential wall of the cup-shaped filter on the side of the opening, and A diameter expansion prevention element is positioned between the circumferential wall of the cup-shaped filter, on the side of the opening, and an inner circumferential wall surface of the diffuser section, on the side of a closed end surface, and the diameter expansion prevention element blocks a diameter expansion on the circumferential wall of the cup-shaped filter, on the side of the opening.

[0040] When the combustion gas entering the diffuser section passes through the cylindrical filter or the cup-shaped filter and is discharged from the gas outlet, the cylindrical filter or the cup-shaped filter may be radially deformed outwards under pressure on the side of the closed end face of the diffuser section during the passage of the combustion gas.

[0041] If the filter deforms to expand radially in this way, the second gap is reduced, which can impair the cooling and filtration effects. However, the inclusion of a diameter expansion limiter prevents such problems from occurring.

[0042] The gas generator according to the present invention has a simple and lightweight structure and exhibits cooling and filtering effects for a combustion gas.

[0043] The gas generator according to the present invention is used as a gas generator for an airbag device that is mounted in an automobile. Description of embodiments (1) Gas generator according to embodiment 1

[0044] In a gas generator 1, which is located in Fig. Figure 1 shows a cylindrical housing 10, which is an outer shell container, a cylindrical housing main body section 11, and a diffuser section 30. The cylindrical housing main body section 11 and the diffuser section 30 are made of a metal, such as stainless steel.

[0045] A detonator 15 is installed in a first end 12a of the cylindrical housing main body section 11. Within the detonator 15, a detonator main body, which has a detonator section 16, is fixed to a detonator collar 17. If necessary, a known transfer charge can be used. An O-ring 18 for moisture sealing is positioned between the detonator collar 17 and an inner wall surface 11a of the cylindrical housing main body section 11.

[0046] A second end 12b on the opposite side in a direction of an axis X to the first end 12a of the cylindrical housing main body section 11 is closed by the diffuser section 30, which is provided with gas discharge ports 31.

[0047] The diffuser section 30 has a closed end surface 32 and a circumferential wall 33. In the embodiment shown in Fig. As shown in Figure 1, the cylindrical housing main body section 11 and the diffuser section 30 are welded to a welded section 19.

[0048] A plurality of gas outlet connections 31 are evenly distributed in a circumferential direction and are sealed from the inside with an aluminium sealing strip 34.

[0049] In the embodiment described in Fig. As shown in Figure 1, an annular stepped surface 35 is formed at a boundary section between the cylindrical housing main body section 11 and the diffuser section 30. The annular stepped surface 35 is formed because an inner diameter (D1) of the cylindrical housing main body section 11 and an inner diameter (D2) of the diffuser section 30 satisfy D1 > D2.

[0050] A large section of the cylindrical housing main body section 11 and the diffuser section 30 each have a constant inner diameter in Fig. 1. However, if the inner diameters of the same are not constant, then D1 and D2 are each an inner diameter at the side of the first end 12a and an inner diameter at the side of the second end 12b, which are continuous with a ring step. In other words, if the respective inner diameters are not constant, for example in Fig. 1, D1 is an inner diameter of a section adjacent to the left of the ring-stepped surface 35 in the housing main body section and D2 is an inner diameter of a section adjacent to the right of the ring-stepped surface 35 in the diffuser section 30.

[0051] An interior space of the cylindrical housing main body section 11 is a combustion chamber 20, which accommodates a gas generating agent 21. If necessary, a holder for adjusting the capacity of the combustion chamber 20 can be positioned within the combustion chamber 20 in accordance with a fill level of the gas generating agent 21.

[0052] The combustion chamber 20 and the diffuser section 30 are divided by a cup-shaped element 40. The cup-shaped element 40 is made of iron, stainless steel, or the like, and, as shown in Fig. 1 and in (a) in Fig. As shown in Figure 2, the cup-shaped element 40 has a base surface 41, a circumferential wall 42 which is formed with a connecting hole 43, and an opening 44. A plurality of connecting holes 43 are formed equally distributed in a circumferential direction.

[0053] An end face of the opening 44 of the cup-shaped element 40 has an enlarged-diameter section 45 that expands outwards. The enlarged-diameter section 45 includes an annular enlarged-diameter section 45a, which extends in the same direction as the circumferential wall 42, and an annular inclined surface 45b, which is positioned between the annular enlarged-diameter section 45a and the circumferential wall 42. The outer diameter of the ring-enlarged-diameter section 45a is larger than the outer diameter of the circumferential wall 42. The cup-shaped element 40 is pressed into the housing main body section 11 by setting a dimension of the outer diameter of the enlarged-diameter section 45 and a dimension of the inner diameter of the cylindrical housing main body section 11.

[0054] As a form of the cup-shaped element 40, various shapes can be applied in association with shapes of the cylindrical housing main body section 11 and the diffuser section 30. (b) Fig. Figure 2 shows a cup-shaped element in which a section corresponding to the enlarged diameter section 45 in (a) in Fig. 2, a standard flange 46 is. (c) Fig. Figure 2 shows a cup-shaped element in which the enlarged diameter section 45, shown in (a) in Fig. 2, is not provided for. (d) Fig. Figure 2 shows a cup-shaped element in which an outer diameter (d1) of the base surface 41 and an outer diameter (d2) of the opening 44 d2 > d1, and the circumferential wall 42a, which extends from the base surface 41 to the opening 44, is an inclined surface. (e) Fig. Figure 2 shows a cup-shaped element in which a folded section 47, extending from the flange 46 to the bottom surface 41, is additionally attached to the flange 46, as shown in (b). Fig. 2, is planned.

[0055] If the cup-shaped element 40, shown in (a) in Fig. 2, in which the cylindrical housing 10 is positioned, the bottom surface 41 is on the side of the first end 12a, and the ring-enlarged diameter section 45a of the enlarged diameter section 45 of the opening 45 is in contact with the ring-stepped surface 35. This creates a first gap 25 between the circumferential wall 42 and the inner wall surface 11a of the cylindrical housing main body section 11, which is radially opposite the circumferential wall 42. The width of the first gap 25 is equal to the difference between the outer diameter of the circumferential wall 42 and the ring-enlarged diameter section 45a of the enlarged diameter section 45.

[0056] The combustion chamber 20 and the diffuser section 30 are connected to each other through the connecting hole 43 via the first gap 25.

[0057] A cylindrical filter 50 is positioned in a space surrounded by the cup-shaped element 40 and the diffuser section 30. In the cylindrical filter 50, a first end surface 51 is in contact with the bottom surface 41 of the cup-shaped element 40, and a second end surface 52, on the opposite side in the direction of axis X, is in contact with the closed end surface 32 of the diffuser section 30.

[0058] In the cylindrical filter 50, an outer circumferential surface 53a of a circumferential wall 53, on the side of the first end surface 51, is in contact with the inner wall surface 42a of the circumferential wall 42 of the cup-shaped element 40. A second gap 37 is formed between the remaining outer circumferential surface 53a of the circumferential wall 53, on the side of the second end surface 52, and the circumferential wall 33, which is provided with the gas discharge connections 31 of the diffuser section 30.

[0059] The cylindrical filter 50 is positioned such that a central axis of the cylindrical filter 50 is aligned with the axis X of the cylindrical housing 10.

[0060] The connecting holes 43 of the cup-shaped element 40 are arranged to be closer to the first end face 51 of the cylindrical filter 50 and to face the first gap 25. The gas discharge ports 31 of the diffuser section 30 are designed to be closer to the second end face 52 of the cylindrical filter 50.

[0061] With reference to an area (A1) in which the circumferential wall 53 of the cylindrical filter 50 and the circumferential wall 42 of the cup-shaped element 40 are in contact with each other, and an area (A2) in which the circumferential wall 53 of the cylindrical filter 50 faces the second gap 37, A2 is essentially 70% if the total area of ​​A1 and A2 is 100%.

[0062] A cylindrical bearing element 60, which is open on the side of the first end 12a and closed on the side of the second end 12b, is further positioned in the cylindrical housing main body section 11.

[0063] The cylindrical bearing element 60 is used to define a filling chamber for receiving a gas-generating agent and to support the cup-shaped element 40 and the cylindrical filter 50 in the direction of the X-axis. The cylindrical bearing element 60 can be omitted if the cup-shaped element 40 is fixed. It should be noted that the filling chamber is also contained within the combustion chamber. The cylindrical bearing element 60 is made of a metal, such as stainless steel.

[0064] The cylindrical bearing element 60 has an outer diameter that is smaller than the inner diameter of the cylindrical housing main body section 11, and a cylindrical gap 65 is formed between the cylindrical bearing element 60 and the cylindrical housing main body section 11. A plurality of gas passage holes 63 are formed in the cylindrical bearing element 60, evenly distributed in an axial and a circumferential direction on a circumferential wall 61. The filling chamber and the cylindrical gap 65 are connected by the gas passage holes 63.

[0065] The cylindrical bearing element 60 has an enlarged diameter section 66 at an opening on the side of the detonator 15, an outer circumferential edge 66a of the enlarged diameter section 66 is in contact with the inner wall surface 11a of the cylindrical housing main body section 11, and a closed end surface 62 is in contact with the bottom surface 41 of the cup-shaped element 40.

[0066] The outer diameter of the outer circumferential edge 66a is slightly larger than the inner diameter of the cylindrical housing main body section 11. When the cylindrical bearing element 60 is positioned in the cylindrical housing main body section 11, the enlarged diameter section 66 is pressed into the inner wall surface 11a of the cylindrical housing main body section 11 due to the elasticity of the enlarged diameter section 66. If the enlarged diameter section 66 is annular, no gap occurs in the pressed-in section.

[0067] In the gas generator 1 according to the present invention, a cylindrical filter 150, shown in Fig. 3, instead of the cylindrical filter 50, shown in Fig. 1. The cylindrical filter 150 includes a first end face 151, a second end face 152 and a circumferential wall 153, and the circumferential wall 153 includes a thick-walled section 153a on the side of the first end face 151 and a thin-walled section 153b on the side of the second end face 152.

[0068] A ring-stepped surface is formed between the thick-walled section 153a and the thin-walled section 153b, however, an inclined surface inclined from the thick-walled 153a to the thin-walled section 153b may be formed at this point.

[0069] The connecting holes 43 of the cup-shaped element 40 face only the thick-walled section 153a. It should be noted that, in another embodiment, the thickness of the circumferential wall 153 of the cylindrical filter 150 can decrease from the first end face 151 to the second end face 152.

[0070] Operation of gas generator 1, shown in Fig. 1, is described.

[0071] When the igniter 15 is actuated, the gas-generating agent 21 within the combustion chamber 20 is ignited and burns to produce a combustion gas. The combustion gas passes through the gas passage holes 63 of the cylindrical bearing element 60 and flows to the second end 12b, while flowing in and out of the cylindrical gap 65 and the filling space.

[0072] The combustion gas then reaches the first gap 25, passes through the connecting holes 43 and the cylindrical filter 50 into a section closer to the first end surface 51, enters the diffuser section 30, passes through the cylindrical filter 50 again, and enters the second gap 37. Fig. 1 is an outer surface of the circumferential wall 53 on the side of the first end surface 51 of the cylindrical filter 50 in contact with the inner wall surface 42a of the circumferential wall 42, provided with the connecting holes 43 of the cup-shaped element 40. As a result, substantially the entire amount of gas passing through the connecting holes 43 enters a space within the cylindrical filter 50.

[0073] Subsequently, the combustion gas passes through the circumferential wall 53 of the cylindrical filter 50 on the side of the second end surface 52, tears the sealing band 34, and is released from the gas discharge connections 31.

[0074] Since the combustion gas passes through the single cylindrical filter 50 twice in this way, the cooling effect and the filtering effect are improved compared to the case where the combustion gas passes through a filter only once.

[0075] Furthermore, compared to the case where filters are positioned separately in multiple locations, the number of filters is reduced, and parts necessary to fix the filters are omitted.

[0076] Furthermore, since the cylindrical filter 50 is positioned such that one of its central axis is aligned with the X-axis of the cylindrical housing main body section 11, when the combustion gas makes a first pass, it passes through the portion of the cylindrical filter 50 closer to the first end face 51, and when the combustion gas makes a second pass, it passes through the portion of the cylindrical filter 50 closer to the second end face 52. As a result, the interior of the cylindrical filter 50 acts as a space for collecting residues, gas blockage due to clogging by residues is less likely compared to a solid column filter, and the output is stabilized. Furthermore, the second gap 37 allows the combustion gas to pass through another area of ​​the cylindrical filter 50.This beneficial effect is further supported by setting a range expressed as A2 / (A1 + A2) × 100.

[0077] Additionally, when the combustion gas enters the cylindrical filter 50, combustion residues contained in the combustion gas adhere to irregularities of the inner wall surface of the cylindrical filter 50 and are more easily captured by the cylindrical filter 50. (2) Gas generator according to embodiment 2

[0078] Gas generators 1A and 1B according to embodiment 2 are described with reference to (a) and (b) in Fig. 4 described. The gas generators 1A and 1B, which are shown in (a) and (b) in Fig. The ones shown in figures 4 are the same as the gas generator 1, which is in Fig. 1 is shown, except for one type of filter.

[0079] A cup-shaped filter 250, which is in (a) in Fig. Figure 4 shows a base surface 251, a circumferential wall 252, and an opening 253. In the cup-shaped filter 250, the base surface 251 is aligned with the base surface 41 of the cup-shaped element 40, and an end surface of the opening 253 of the cup-shaped filter 250 is aligned with the closed end surface 32 of the diffuser section 30.

[0080] The connecting holes 43 of the cup-shaped element 40 are positioned closer to the bottom surface 251 of the cup-shaped filter 250 and facing the first gap 25. The gas discharge ports 31 of the diffuser section 30 are positioned closer to the opening 253 of the cup-shaped filter 250.

[0081] The mass of the cup-shaped filter 250 is greater than that of the cylindrical filter 50, which is in Fig. 1 is shown, and the cylindrical filter 150, which is in Fig. Figure 3 shows a mass of the base surface 251. However, the base surface 251 in the section which faces the inside of the diffuser section 30 is an irregular surface and a surface area is thereby increased, which improves the combustion residue collection effect.

[0082] A cup-shaped filter 350, which is in (b) in Fig. Figure 4 shows a base surface 351, a circumferential wall 352, and an opening 353. The thickness of the base surface 351 is greater than the thickness of the circumferential wall 352 and is greater than the inner diameter of the connecting holes 43 of the cup-shaped element 40. In the cup-shaped filter 350, the base surface 351 is in contact with the base surface 41 of the cup-shaped element 40, and an end surface of the opening 353 of the cup-shaped filter 350 is in contact with the closed end surface 32 of the diffuser section 30.

[0083] The cup-shaped filter 350 faces the connecting holes 43 of the cup-shaped element 40, such that an intermediate section in the thickness of the base surface 351 corresponds to the center of the connecting holes 43 of the cup-shaped element 40. As a result, all of the connecting holes 43 face the base surface 351, and the combustion gas entering from the connecting holes 43 inevitably flows radially inward through the base surface 351 of the cup-shaped filter 350, thereby improving both the cooling and filtration effects.

[0084] Gas generators 1C, 1D, and 1E according to different embodiments are described with reference to (a) to (c) in Fig. 5 described. The gas generators 1C, 1D, and 1E, which are shown in (a) to (c) in Fig. The ones shown in 5 are the same as the gas generator 1, which is in Fig. Figure 1 shows, except that a diameter expansion prevention element for the cylindrical filter 50 is positioned therein.

[0085] It can be observed that in the gas generators 1C, 1D, and 1E, shown in (a) to (c) in Fig. 5, the cylindrical filter, shown in Fig. 3, or the cup-shaped filters, shown in (a) and (b) in Fig. 4, can be used instead of the cylindrical filter 50.

[0086] In the gas generator 1C according to the embodiment shown in (a) in Fig. 5, a ring-diameter expansion-prevention element 70 is positioned between the circumferential wall 53 of the cylindrical filter 50, on the side of the second end face 52, and the inner circumferential wall surface 30a of the diffuser section 30, on the side of the closed end face 32. In the ring-diameter expansion-prevention element 70, an inner circumferential surface of the same abuts the circumferential wall 53 of the cylindrical filter 50, and, from the standpoint of preventing an overlap with the sealing strip 34, an outer circumferential surface of the same faces the circumferential wall 33 of the diffuser section 30 at a small distance.

[0087] In the gas generator 1D according to the embodiment shown in (b) in Fig. 5, a flat, cup-shaped diameter expansion-prevention element 80 is positioned between the circumferential wall 53 of the cylindrical filter 50, on the side of the second end face 52, and the inner circumferential wall surface 30a of the diffuser section 30, on the side of the closed end face 32. The cup-shaped diameter expansion-prevention element 80 has a bottom surface 81 and a circumferential wall 82.

[0088] In the cup-shaped diameter expansion-prevention element 80, the bottom surface 81 is in contact with the closed end surface 32 of the diffuser section 30, an inner circumferential surface of the circumferential wall 82 is in contact with the circumferential wall 53 of the cylindrical filter 50, and, from the point of view of preventing overlap with the sealing strip 34, an outer circumferential surface of the circumferential wall 82 faces the circumferential wall 33 of the diffuser section at a small distance.

[0089] In the gas generator 1E according to the embodiment shown in (c) in Fig. Figure 5 shows a diameter expansion prevention element 90, which is formed from a plurality of independent projections, positioned between the circumferential wall 53 of the cylindrical filter 50, on the side of the second end surface 52, and the inner circumferential wall surface 30a of the diffuser section 30, on the side of the closed end surface 32.

[0090] The diameter expansion-prevention element 90, which is formed from a plurality of independent projections, projects inwards from the circumferential wall 33 of the diffuser section 30. A plurality (for example, 2 to 8) of the independent projections are formed equally distributed in one circumferential direction and are not in contact with the sealing strip 34.

[0091] The diameter expansion-prevention element 90, which is formed from a plurality of independent projections, lies against or faces a small gap in the circumferential wall 53 of the cylindrical filter 50, on the side of the second end face 52. It should be noted that the diameter expansion-prevention element 90 can be formed from a continuous annular projection or a flange that is integrally formed with the cylindrical filter 50, on the side of the second end face 52, instead of the plurality of independent projections.

[0092] The gas generators 1C, 1D and 1E, shown in (a) to (c) in, operate with the arrangement of the diameter expansion-prevention element 70, 80 and 90. Fig. 5, as follows.

[0093] A combustion gas, which has passed through the cylindrical filter 50 from the connecting holes 43 of the cup-shaped element 40 and then enters the diffuser section 30, passes through the cylindrical filter 50 once more, enters the second gap 37, and subsequently tears the sealing band 34, and is discharged from the gas outlet connections 31, as described in the operation description of the gas generator, which is located in Fig. 1 is shown.

[0094] When the combustion gas passes through the cylindrical filter 50 a second time and is discharged from the gas outlet ports 31, the cylindrical filter 50 can deform at the side of the second end face 52 to expand radially outward under the pressure generated by the passage of the combustion gas, thereby reducing the second gap 37. However, since the diameter expansion-prevention element 70, 80 and 90 in the gas generators 1C, 1D and 1E shown in (a) to (c) in Fig. As shown in Figure 5, the cylindrical filter 50 is positioned on the side of the second end face, preventing it from being deformed radially outwards, and thus the second gap 37 is not reduced. Accordingly, a cooling effect and a filtering effect are fully achieved by the cylindrical filters 50.

Claims

[1] A gas generator comprising: a cylindrical housing (10) comprising a cylindrical housing main body section (11) and a diffuser section (30); an ignition device (15) which is positioned at a first end of the cylindrical housing main body section (11), the diffuser section (30) is provided with a gas discharge port (31) and closes a second end of the same on an axial opposite side of the first end; a combustion chamber (20) which accommodates a gas generating means (21) is formed in an interior of the cylindrical housing main body section (11); a cup-shaped element (40) that divides the combustion chamber (20) and the diffuser section (30), The cup-shaped element (40) has a base (41), a circumferential wall (42) which has a connecting hole (43), and an opening (44). The cup-shaped element (40) is positioned such that, the circumferential wall (42) extends radially outwards towards an inner wall surface (11a) of the cylindrical housing main body section (11) in order to form a first gap (25) between them, a filter (50, 150) positioned in a space surrounded by the diffuser section (30), and the connecting hole (43) of the cup-shaped element (40) faces the first gap (25), and the gas discharge port (31) of the diffuser section (30) is formed closer to the second end face (52, 152) of the filter (50, 150), with the cup-shaped element (40) positioned such that, the bottom surface (41) is arranged on the side of the first end of the cylindrical housing (10), the opening (44) is arranged on the side of the second end of the same, the filter (50, 150) is positioned in a space surrounded by the cup-shaped element (40), characterized by , that the filter (50, 150) is positioned such that a first end surface (51, 151) of the same is in contact with the bottom surface (41) of the cup-shaped element (40), a second end surface (52, 152) of the same is on the opposite side to the first end surface (51, 151) in contact with a closed end surface (32) of the diffuser section (30), the connecting hole (43) of the cup-shaped element (40) is formed at a position closer to the first end face (51, 151) of the filter (50, 150), and the filter (50, 150) is a cylindrical filter (50, 150) with an outer circumferential surface (53a) of a circumferential wall (53, 153) in contact with an inner wall surface (42a) of the circumferential wall (42) of the cup-shaped element (40), and a second gap (37) is formed between the gas discharge connection (31) and an outer surface of the circumferential wall (53, 153) of the cylindrical filter (50, 150) on the side of the second end surface (52, 152). [2] The gas generator according to claim 1, characterized by , that the circumferential wall (153) of the cylindrical filter (150) includes a thick-walled section (153a) on the side of the first end face (151), and a thin-walled section (153b), with a thickness less than the thickness of the thick-walled section (153a), on the side of the second end face (152), and only the thick-walled section faces the connecting hole (43) of the cup-shaped element (40). [3] A gas generator comprising: a cylindrical housing (10) comprising a cylindrical housing main body section (11) and a diffuser section (30); an ignition device (15) positioned at a first end of the cylindrical housing main body section (11), a diffuser section (30) is provided with a gas discharge port (31) and closes a second end of the same on an axial opposite side to the first end; a combustion chamber (20) which includes a gas generating means (21) which is present in an interior of the cylindrical housing main body section (11); a cup-shaped element (40) that divides the combustion chamber (20) and the diffuser section (30), The cup-shaped element (40) has a base (41), a circumferential wall (42) which has a connecting hole (43), and an opening (44). The cup-shaped element (40) is positioned such that, the circumferential wall (42) extends radially outwards against an inner wall surface (11a) of the cylindrical housing main body section (11) to form a first gap (25) between them, a filter (250, 350) positioned in a space surrounded by the diffuser section (30), the connecting hole (43) of the cup-shaped element (40) faces the first gap (25), and the gas discharge port (31) of the diffuser section (30) is formed closer to the opening (253, 353) of the filter (250, 350), with the cup-shaped element (40) being positioned such that, the bottom surface (41) is arranged on the side of the first end of the cylindrical housing (10), and the opening (44) is arranged on the side of the second end of the same, characterized by , that the filter is a cup-shaped filter (250, 350) which has a bottom surface (251, 351) and a circumferential wall (252, 352) and an opening (253, 353), and the filter (250, 350) is positioned such that the bottom surface (251, 351) of the filter (250, 350) is in contact with the bottom surface (41) of the cup-shaped element (40), an end surface of the filter (250, 350) is in contact with a closed end surface (32) of the diffuser section (30), and the connecting hole (43) of the cup-shaped element (40) is formed at a position closer to the bottom surface (251, 351) of the filter (250, 350), wherein the cup-shaped filter (250, 350) with an outer circumferential surface of the circumferential wall (252, 352) in contact with an inner wall surface of the circumferential wall of the cup-shaped element (40). [4] The gas generator according to claim 3, characterized by , that a thickness of the bottom surface (351) of the cup-shaped filter (350) is greater than a thickness of the circumferential wall (352) of the cup-shaped filter (350) and greater than an inner diameter of the connecting hole (43) of the cup-shaped element (40), and only the bottom surface (351) of the cup-shaped filter (350) faces the connecting hole (43) of the cup-shaped element (40). [5] The gas generator according to claim 1, characterized by, that an outer diameter of the cup-shaped element (40) at the side of the opening (44) is larger than an outer diameter of the base surface (41) of the same, a ring-stepped surface (35) is formed on an inner wall surface (11a) of the cylindrical housing main body section (11) on the side of the diffuser section (30), the end surface of the opening (44) of the cup-shaped element (40) is in contact with the ring-stepped surface (35) in order to form the first gap (25) between the circumferential wall (42) of the cup-shaped element (40), which has a connecting hole (43), and an inner wall surface (11a) of the cylindrical housing main body section (11), and the outer surface of the circumferential wall (53, 153) of the cylindrical filter (50, 150), on the side of the first end surface (51, 151) in contact with the inner surface of the circumferential wall (42) of the cup-shaped element (40), which has a connecting hole (43). [6] The gas generator according to claim 3, characterized by , that an outer diameter of the cup-shaped element (40) is larger at the side of the opening (44) than an outer diameter at the bottom surface (41) of the same, a ring-stepped surface (35) is formed on an inner wall surface (11a) of the cylindrical housing main body section (11), on the side of the diffuser section (30), the end surface of the opening (44) of the cup-shaped element (40) is in contact with the ring-stepped surface (35) in order to form the first gap (25) between the circumferential wall (42) of the cup-shaped element (40), which has a connecting hole (43), and an inner wall surface (11a) of the cylindrical housing main body section (11), and the outer surface of the circumferential wall (252, 352) of the cup-shaped filter (250, 350) is in contact with the inner surface of the circumferential wall (42) of the cup-shaped element (40) on the side of the bottom surface (251, 351), which has a connecting hole (43), and a second gap (37) is formed between the gas discharge connection (31) and an outer surface of the circumferential wall (252, 352) of the cup-shaped filter (250, 350) on the side of the opening (253, 353). [7] The gas generator according to claim 5, characterized by , that with reference to an area (A1) in which the circumferential wall (53, 153) of the cylindrical filter (50, 150) and the circumferential wall (42) of the cup-shaped element (40) are in contact with each other, and an area (A2) in which the circumferential wall (53, 153) of the cylindrical filter (50, 150) faces the second gap (37), A2 is in a range of more than 50% to 80% if an entire area of ​​A1 and A2 is 100%. [8] The gas generator according to claim 6, characterized by , that with reference to an area (A1) in which the circumferential wall (252, 352) of the cup-shaped filter (250, 350) and the circumferential wall (42) of the cup-shaped element (40) are in contact with each other, and an area (A2) in which the circumferential wall (252, 352) of the cup-shaped filter (250, 350) faces the second gap (37), A2 is in a range of more than 50% to 80% if an entire area of ​​A1 and A2 is 100%. [9] The gas generator according to claim 5, characterized by, that a diameter expansion prevention element (70, 80, 90) is positioned between the circumferential wall (53) of the cylindrical filter (50) on the side of the second end face (52) and an inner circumferential wall surface of the diffuser section (30), on the side of a closed end face (32), and the diameter expansion prevention element (70, 80, 90) blocks a diameter expansion on the circumferential wall (53) of the cylindrical filter (50) on the side of the second end face (52). [10] The gas generator according to claim 6, wherein a diameter expansion prevention element is positioned between the circumferential wall of the cup-shaped filter, on the side of the opening, and an inner circumferential wall surface of the diffuser section, on the side of a closed end surface, and the diameter expansion prevention element blocks a diameter expansion on the circumferential wall of the cup-shaped filter on the side of the opening.

Images