Gas generator with heat insulation layer

Abstract

The present invention provides an ignition device comprising an igniter fixed to an igniter collar, a first cup element filled with a gas-generating component, and a second cup element. The first cup element covers the detonator collar, so that a section is enclosed which contains a detonator section of the detonator. The second cup element covers the detonator collar, thus enclosing the first cup element. A gap is formed between an outer surface of the first cup element and an inner surface of the second cup element to function as a heat insulation layer. The first cup element has a first opening device, and the second cup element has a second opening device, and at least one of the first opening device and the second opening device is closed before activation and is open only when the gas is generated by the gas generating component.

Description

[0001] The present invention relates to a gas generator according to the preamble of independent claim 1. Such a gas generator is known from US patent 2006 / 0119086 A1.

[0002] As a gas generator in which a gas generating agent is used as a gas source, such a gas generator is used which includes two combustion chambers, each accommodating a gas generating agent, and two igniters for igniting and burning the respective gas generating agents.

[0003] In such a gas generator, when one of the igniters is activated and the gas-generating agent contained in one of the combustion chambers is ignited and burning, it is necessary to ensure that the heat of combustion does not ignite the gas-generating agent in the other combustion chamber.

[0004] US 6 032 979 A discloses a dual-type gas generator comprising a first igniter assembly 54 and a second igniter device 90 in a housing 12 formed by a base section 14 and a diffuser cap section 16.

[0005] A second combustion chamber 82, which contains the second ignition device 90, is positioned within a cup element 84 that is positioned within a first combustion chamber 34, and is filled with a second gas-generating material 86. Furthermore, an insulator-barrier material 106 is positioned in a section of an outer side (a circumferential wall) of the cup element 84.

[0006] The insulator-barrier material 106 functions in such a way that the second gas-generating material 86, which is positioned in the second combustion chamber 82, is prevented from coming into contact with a combustion product of the first gas-generating material 36 (to prevent the second gas-generating material from igniting upon contact). The insulator-barrier material 106 ruptures when the second gas-generating material 86 ignites, and the insulator-barrier material 106 also functions to direct a combustion product of the second gas-generating material 86 to the first combustion chamber 34.

[0007] Fiberglass, which includes adhesive-baked foil tape, is listed as a special material for the insulator-barrier material 106.

[0008] The object of the present invention is to provide a gas generator that is easy to assemble and hardly affected by thermal influences from the outside atmosphere. This object is achieved according to the invention by a gas generator with the features of independent claim 1. Preferred embodiments are set out in the dependent claims. Description of the drawings

[0009] The present invention is more fully understood from the detailed description given below and the accompanying drawings, which are provided for illustrative purposes, wherein: [ Fig. 1] Fig. Figure 1 shows in (a) an axial sectional view of an ignition device for a gas generator, and in (b) an axial sectional view of an igniter and an igniter collar, as shown in (a); [ Fig. 2] Fig. Figure 2 shows in (a) a front view of a first cup element used in the ignition device shown in (a) in Fig. 1 is shown, and in (b) and (c) a front view of a first cup element according to another embodiment; [ Fig. 3] Fig. Figure 3 shows in (a) and (b) a front view of a second cup element in an embodiment different from that in (a). Fig. 1 shown; [ Fig. 4] Fig. Figure 4 shows an axial sectional view of an ignition device of an embodiment different from (a) in Fig. 1 shown; and [ Fig. 5] Fig. Figure 5 shows an axial sectional view of a dual-type gas generator according to the present invention. Detailed description of preferred embodiments

[0010] In the disclosure of US 6 032 979 A, ​​it is preferred, in order to prevent the cup element 84 from coming into contact with the combustion product of the first gas-generating material 36, to cover an entire surface of the cup element 84 with the insulator-barrier material 106. However, it is difficult to cover the entire surface with the fiberglass, which incorporates adhesive-baked foil tape.

[0011] Accordingly, as in Fig. As shown in Figure 1, there is no alternative to using a method of covering only one perimeter wall surface with the fiberglass, which contains the adhesive-baked foil tape, which does not provide sufficient insulation and barrier function.

[0012] An ignition device is shown which is easy to assemble and hardly affected by thermal influences from the outside atmosphere, and a gas generator according to the invention which uses it.

[0013] An electric igniter, which is used in a known gas generator for an airbag apparatus, can be used as the igniter.

[0014] The detonator includes a detonator main body, which has a firing section, and an electrically conductive pin that protrudes from the detonator main body.

[0015] Part of the main body of the detonator is fixed by a metallic detonator collar.

[0016] A first cup element includes a base, a perimeter wall and an opening arranged to face the base.

[0017] The gas generation component is contained in the first cup element.

[0018] The gas generation component can be a transfer filling used for an igniter from a known gas generator for an airbag device, a gas generation agent used in the known gas generator, known black powder, known smokeless powder, and the like.

[0019] A second cup-shaped element includes a base, a perimeter wall, and an opening, arranged to face the base.

[0020] The second cup element is larger than the first cup element, and the first and second cup elements cover the detonator, so that the first cup element is on the inside and the second cup element is on the outside. This creates a gap (an air layer) between the base surfaces and their surrounding walls.

[0021] Since air is highly efficient at insulating against heat, the gap acts as a heat insulation layer.

[0022] The first cup element has a first opening device. The first opening device is preferably formed in the circumferential wall, but the first opening device can be formed in the bottom surface or can be formed in both the circumferential wall and the bottom surface.

[0023] The second cup element has a second opening device. The second opening device is preferably formed in the circumferential wall, but the second opening device can be formed in the bottom surface or can be formed in both the circumferential wall and the bottom surface.

[0024] The first opening device of the first cup element and the second opening device of the second cup element can be designed facing each other or can be designed in different positions.

[0025] Since the gas generation component is formed in the first cup element to be hardly affected by external thermal influences, one of the first and second opening devices is closed before activation, and is open only when gas is generated by the gas generation component.

[0026] The opening device, which is only open when the gas can be generated, can be: a through-hole provided in the cup element (a first cup element or a second cup element) in a thickness direction and in a closing element that closes the through-hole, such as a metallic sealing strip; and a fragile section (for example, a groove section or a thin section) formed in the cup element (a first cup element or a second cup element).

[0027] According to the present disclosure, both the first opening device of the first cup element and the second opening device of the second cup element can be adapted to open only when gas is generated, and preferably only the second opening device of the second cup element is adapted to open only when the gas is generated.

[0028] One embodiment of the present invention provides a gas generator for a seatbelt retractor, which includes the ignition device described above.

[0029] The ignition device of the present disclosure is used as an ignition device for a known gas generator for an airbag device.

[0030] Furthermore, the ignition device of the present disclosure can, for example, be used in an independent gas generator or can be used as a gas generator for a seatbelt retractor.

[0031] In one embodiment, the present disclosure relates to the ignition device, wherein the first cup element and the second cup element are arranged such that a first projection formed on the outer surface of the first cup element is in contact with the inner surface of the second cup element, or a second projection formed on the inner surface of the second cup element is in contact with the outer surface of the first cup element.

[0032] The gap (the air layer), which acts as a heat insulation layer, is maintained between the first cup element and the second cup element.

[0033] However, if the second cup element is inclined to be in contact with the first cup element due to the absorption of pressure including heat from the outside, it is conceivable that the gap will not act as a sufficient heat insulation layer.

[0034] If one of the first projections and the second projection is provided as described above, the gap retains the function of the heat insulation layer even if the problem described above occurs.

[0035] The first and second projections can be a combination of multiple independent projections or one, two, or more circumferential projections. The combination of multiple independent projections is preferred from the perspective of reducing heat transfer from the second cup element to the first cup element.

[0036] If the combination consists of multiple independent projections, approximately two to eight projections, formed at equal intervals in a circumferential direction, can be used, or the approximately two to eight projections can be formed in multiple steps in a vertical direction. The first projection section or the second projection section can be formed on the circumferential wall near the bottom surface of the first cup element or the second cup element.

[0037] In one embodiment, the present disclosure relates to the ignition device, wherein the first cup element is made of a material which has a lower thermal conductivity than the second cup element.

[0038] In one embodiment, the present disclosure relates to the ignition device, wherein the first cup element is made of a resin and the second cup element is made of a metal.

[0039] With the combination of the first and second cup elements described above, the second cup element is hardly thermally deformed on its outer surface, even when exposed to external thermal influences. Furthermore, this design prevents the gas generation component housed in the first cup element from igniting unintentionally, due to the thermal insulation effect of both the gap (the air layer) and the first cup element.

[0040] If the first cup element is a resin and the second cup element is metal, the first protruding section is preferably formed on the first cup element only to maintain the gap (the air layer) to prevent damage to the first cup element.

[0041] In one embodiment, the present disclosure relates to the ignition device, wherein the ignition collar has a metal section and a low thermally conductive section made of a material having a lower thermal conductivity than the metal of the metal section, and an opening of the first cup element on an inner circumferential wall at the opening of the same are in contact with the low thermally conductive section.

[0042] As described above, due to the gap (the air layer) maintained between the first and second cup elements, the cup elements are not in direct contact with each other. However, the cup elements are in indirect contact with each other via the metallic detonator collar, since their openings are in contact with the metallic detonator collar.

[0043] This allows heat (a temperature increase) from the second cup element, which is influenced by thermal influence from the outside, to be transferred to the first cup element via the metallic detonator collar.

[0044] If the low-thermal-conducting section is formed in the detonator collar and the opening of the first cup element and the inner circumferential wall at the opening are in contact with the low-thermal-conducting section, the heat (temperature rise) of the second cup element is hardly transferred to the first cup element.

[0045] The low thermally conductive section is preferably made of a resin, ceramic, or rubber, such as silicone rubber.

[0046] In one embodiment, the present disclosure relates to the ignition device, wherein the detonator collar has a smaller diameter section, an intermediate diameter section and a larger diameter section, arranged in this order from the ignition section in an ascending manner of the outer diameter, The larger-diameter section is made of metal, and at least the smaller-diameter section includes a low-thermal-conducting section made of a material that has a lower thermal conductivity than the metal of the metal section. A first circumferential surface is formed between the smaller-diameter section and the intermediate-diameter section, which is obtained by a difference in their outer diameters, and a second circumferential surface is formed between the intermediate-diameter section and the larger-diameter section, which is obtained by a difference in their outer diameters, and The first cup element has an opening in contact with the first circumferential surface, and an inner circumferential wall at the opening is pressed into the smaller diameter section.

[0047] The detonator collar, used for the ignition device, has a smaller-diameter section, an intermediate-diameter section, and a larger-diameter section arranged in that order from the ignition section in ascending order of their outer diameters. The smaller-diameter section includes a low-thermal-conductivity section made of a material with a lower thermal conductivity than the metal of the metal section. This provides an attachment point for the first cup element and improves the thermal insulation effect.

[0048] Furthermore, from the perspective of improving the thermal insulation effect, it is preferred that both the smaller diameter section and the intermediate diameter section include a low thermally conductive section made of a material that has a lower thermal conductivity than the metal of the metal section.

[0049] Methods for attaching the second cup element include a method for pressing the second cup element onto the intermediate diameter section of the detonator collar, a method for fixing the second cup element by crimping the larger diameter section, and a method for overlapping, pressing in, or adhesively attaching the second cup element to the circumferential wall of the first cup element or to the bottom wall and the circumferential wall thereof.

[0050] One embodiment of the present invention provides a gas generator comprising, in a housing having a gas delivery port, an ignition device; and a combustion chamber filled with a gas generating agent, wherein the ignition device described above is used as the ignition device.

[0051] One embodiment of the present invention provides a gas generator comprising, in a housing which has the gas delivery connection: an ignition device; a first combustion chamber filled with a first gas generating agent, and a second combustion chamber filled with a second gas generating agent, wherein the ignition device described above is used as the second combustion chamber.

[0052] An advantageous effect of the ignition device of the present disclosure is noticeably demonstrated in a dual-type gas generator according to the present invention, which has a first combustion chamber and a second combustion chamber. However, the present disclosure can be applied to a single-type gas generator having a single combustion chamber.

[0053] When the ignition device of the present disclosure is applied to a dual-type gas generator according to the present invention, the ignition device is used as the second combustion chamber.

[0054] In this case, the gas generation component, incorporated in the first cup element of the ignition device, is used as a gas generation means which corresponds to the second gas generation means in the second combustion chamber.

[0055] With the ignition device of the present disclosure, used as the second combustion chamber, even if the first gas-generating agent in the first combustion chamber burns first and a high-temperature condition is created inside the housing, the heat insulation effect of the gap (the air layer) is shown, so that false ignition of the gas-generating agent in the second combustion chamber (in the first cup element of the ignition device) is prevented.

[0056] The ignition device of the present disclosure has the gap (the air layer) between the first cup element, filled with a gas-generating component, and the second cup element, arranged on the outside of the first cup element.

[0057] As a result, even when heat is applied from the outside, the heat transfer to the inside of the first cup element is suppressed by the heat insulation effect of the gap, and thus the gas-generating component in the first cup element is prevented from being mistakenly ignited by heat from the outside.

[0058] The ignition device of the present disclosure is usable for a gas generator for a seatbelt retractor, an ignition device for a gas generator, and a combustion chamber for a gas generator. Exemplary embodiments of the invention<Zündvorrichtung in Fig. 1>

[0059] An ignition device 1, shown in (a) in Fig. 1, includes a detonator 10, a first cup element 20 and a second cup element 30.

[0060] The detonator 10 has a detonator main body which includes the ignition section 11 and an electrically conductive pin 12 which protrudes from the detonator main body.

[0061] A section of the detonator main body, which includes the ignition section 11 of the detonator 10, is fixed by a detonator collar 13.

[0062] As shown in (a) and (b) in Fig. 1, the fuze collar 13 has a smaller diameter section 14, an intermediate diameter section 15 and a larger diameter section 16, which are arranged in this order from the fuze section 11 in ascending order of the outer diameters.

[0063] Since the smaller diameter section 14 and the intermediate diameter section 15 are made of a resin and the larger diameter section 16 is made of metal, the smaller diameter section 14 and the intermediate diameter section 15 have a lower thermal conductivity than the larger diameter section 16.

[0064] The smaller diameter section 14 and the intermediate diameter section 15 can be designed such that an inner side of the same is made of a metal, integrated with the larger diameter section 16, and the outer side is coated with a resin.

[0065] A polyamide-based resin (for example, Nylon 6-12), a polyimide-based resin, or the like can be used as the resin, and aluminum, iron, stainless steel, or the like can be used as the metal.

[0066] The smaller diameter section 14 has a flat section 14a, from which the ignition section 11 projects, and a first circumferential wall surface 14b.

[0067] The intermediate-diameter section 15 has a first circumferential planar section 17, which is obtained by a difference in the outer diameters between the intermediate-diameter section 15 and the smaller-diameter section 14, and a second circumferential wall surface 15a, which is provided vertically downwards (towards the electrically conductive pin 12) from the first circumferential planar section 17.

[0068] The larger-diameter section 16 has a second circumferential planar section 18, which is obtained by a difference in the outer diameters between the larger-diameter section 16 and the intermediate-diameter section 15, and a third circumferential wall section 16a, which is provided vertically downwards (towards the electrically conductive pin 12) from the second circumferential planar section 18.

[0069] The larger-diameter section 16 has a circumferential projecting section (a crimp section) 18a on the second circumferential flat section 18 on the third circumferential wall section 16a.

[0070] As in Fig. 1 and in (a) in Fig. As shown in Figure 2, the first cup element 20 has a base surface 21, a circumferential wall 22, and an opening 23, arranged to face the base surface 21 in an axial direction. The base surface 21 can be a separate element from the circumferential wall 22.

[0071] An inner circumferential surface of the first cup element 20 at the opening 23 is pressed into the first circumferential wall surface 14b, and a circumferential end 23a of the opening 23 lies against the first circumferential flat section 17.

[0072] A known gas-generating agent 40, which serves as a gas-generating component, is densely filled into the first cup element 20.

[0073] The ignition section 11 of the igniter 10 is enclosed by the first cup element 20 and is in contact with the gas generating agent 40.

[0074] As in (a) in Fig. 1 and in (a) in Fig. As shown in Figure 2, the circumferential wall 22 of the first cup element 20 is provided with a plurality of through-holes 24, which serve as a first opening device. The through-holes 24 extend through the circumferential wall 22 in the thickness direction and are open.

[0075] The majority of through holes 24 are arranged such that the through holes which are formed at equal intervals in the circumferential direction are defined as a group, and a majority of such groups of through holes are formed at intervals in a height direction.

[0076] The first cup element 20 can be, as in (b) and (c) in Fig. 2 shown, be designed instead of the embodiment which has the through holes 24 shown in (a) in Fig. 1 and (a) in Fig. 2.

[0077] In a first cup element 20A, shown in (b) in Fig. 2, are the majority of through holes 24 of the first cup element 20, shown in (a) in Fig. 2, closed from the outside by a sealing strip 25. All through-holes 24 are sealed by a single sealing strip 25 in (b) in Fig. 2 closed, however, multiple sealing strips can be used. During activation, the sealing strip 25 is torn, thus opening the through-holes 24.

[0078] A first cup element 20B, shown in (c) in Fig. 2, has a plurality of fragile sections 24b instead of the through holes 24, shown in (a) and (b) in Fig. 2. The majority of fragile sections 24b are formed by groove sections or thinner sections, and are closed before activation and break to open during activation. In (c) in Fig. 2. Linear fragile sections are formed, however, a circular fragile section (for example, a fragile section formed on the circumference of a circle, or an entire inner side of a circle reduced in thickness) may be formed.

[0079] As in (a) in Fig. 1, Fig. 3 and Fig. As shown in Figure 4, the second cup element 30 has a bottom surface 31, a circumferential wall 32, and an opening 33, arranged to face the bottom surface 31 in an axial direction, and furthermore a flange 34 is formed at the opening 33. The bottom surface 31 can be a separate element from the circumferential wall 32.

[0080] In the second cup element 30, an inner circumferential surface at the opening 33 abuts the second circumferential wall surface 15a, and the flange 34 abuts the second circumferential flat section 18, and thereafter the circumferential projecting section (the crimp section) 18a is bent to fix the flange 34.

[0081] The second cup element 30 can also not be formed with the flange 34, and the second cup element 30 can be pressed in and fixed, similar to the first cup element 20, so that the inner circumferential surface at the opening 33 abuts against the second circumferential wall surface 15a, and the circumferential end of the opening abuts against the second circumferential flat section 18 ( Fig. 5).

[0082] As in (a) in Fig. As shown in Figure 1, the circumferential wall 32 of the second cup element 30 is provided with a plurality of through-holes 35, which serve as a second opening device.

[0083] The through-holes 35 extend through the circumferential wall 32 in a thickness direction and are closed from the inside by the sealing strip 36. The sealing strip 36 can be applied from the outside. During activation, the sealing strip 36 is torn to open the through-holes 35.

[0084] The second cup element 30 can be designed as shown in (a) and (b) in Fig. 3 shown, instead of the embodiment which shows the through holes 35, shown in (a) in Fig. 1, has.

[0085] The second cup element 30A, shown in (a) in Fig. Figure 3 is an embodiment in which a sealing cup 37 replaces the sealing band 36 of the second cup element 30, shown in (a). Fig. 1. During activation, the sealing cup 37 is broken or deformed to open the through-holes 35. An example of the sealing cup 37 can be an element corresponding to a cup-shaped thin-film element 137, shown in Fig. 4 in JP 2007-131 077 A, or an element corresponding to a cup-shaped thin-film element 147 in JP 2007-118 788 A.

[0086] A second cup element 30C, shown in (b) in Fig. 3, has a plurality of fragile sections 38 instead of the through holes 35, shown in (a) in Fig. 1 and in (a) in Fig. 3. The majority of fragile sections 38 are formed by a groove section or a thinner section that is closed before activation and breaks open during activation. In both (a) in Fig. 1 and Fig. 4. The through-holes 35 and the fragile sections 38 can be formed in positions which do not overlap with the through-holes 24 of the first cup element when the through-holes and the fragile sections are open.

[0087] One or both of the through-holes 24 of the first cup element and the through-holes 35 (or the fragile sections 38) of the second cup element 30 are closed prior to activation to ensure a moisture-proof property for the gas-generating agent 40 which is tightly packed into the first cup element.

[0088] Therefore, for example, if a cup element, as shown in (b) or (c) in Fig. 2, when the first cup element 20 is used, the through holes 35 in the second cup element 30 are open, not closed.

[0089] A gap 28 is formed to serve as a heat insulation layer between an outer surface of the circumferential wall 22 of the first cup element 20 and an inner surface of the circumferential wall 32 of the second cup element 30.

[0090] The gap (opening amount) of the gap 28 is preferably uniform. However, for example, in a case where the ignition device 1 of the present disclosure is used in a gas generator in which the bottom surface 31 (the bottom surface 21) is in contact with or close to the housing of the gas generator, and therefore the ignition device is hardly affected by thermal influence due to combustion of the gas-generating agent, the gap between the circumferential wall 22 and the circumferential wall 32 can be relatively large and the gap between the bottom surface 21 and the bottom surface 32 can be relatively small.

[0091] The distance (opening amount) of column 28 can, for example, be set in the range of 0.5 to 2.0 mm.

[0092] The ignition device, shown in (a) in Fig. 1, can be used as a gas generator for a seatbelt retractor, and can be used as an ignition device or a combustion chamber which includes an igniter and a gas generating means, in a known gas generator for an airbag device.

[0093] The ignition device 1 of the present disclosure has the gap 28, which serves as a heat insulation layer when the ignition device is exposed to thermal influence from the outside.

[0094] As in the embodiment shown in (a) in Fig. 1. Since the first cup element 20 is in contact with the smaller diameter section 14 and the intermediate diameter section 15, made of resin, and not with the larger diameter section 16, made of metal, a temperature increase in the first cup element 20 due to thermal conduction from the larger diameter section 16 is prevented.

[0095] This prevents false ignition of the gas generating agent 40 in the first cup element 20, even if the ignition device is exposed to a thermal influence from the outside. <Zündvorrichtung in Fig. 4>

[0096] An ignition device 1A, shown in Fig. 4 is the same as the ignition device 1, shown in (a) in Fig. 1, except that a first cup element 20A is in parts and an attachment position of the sealing strip 36 differs from the first cup element 20 of (a) in Fig. 1 are.

[0097] The first cup element 20A has a plurality of independent projections 27 which are formed on a circumferential wall 22 at a position close to a bottom surface 21 at equal intervals in the circumferential direction, so that they project radially outwards.

[0098] Remote ends of the majority of the independent projections 27 are attached to an inner surface of a circumferential wall 32 of a second cup element 30.

[0099] The majority of independent projections 27 can be formed at different height positions in the axial direction.

[0100] Four independent leads of 27 are in Fig. 4 formed, and three to six projections 27 are sufficient. A continuous circumferential projection can be used instead of the independent projections 27.

[0101] If the first cup element 20A is made of resin, the first cup element 20A and the projections 27 can be integrally formed.

[0102] The independent projection sections 27 are only attached to the first cup element 20A in Fig. 4 formed. But the projections 27 can project radially inwards from an inner surface of the circumferential wall 32 of the second cup element 30 and abut against an outer surface of the circumferential wall 22 of the first cup element 20.

[0103] Furthermore, the projections 27 of both, the first cup element 20 and the second cup element 30, can project forward to abut each other.

[0104] As in Fig. As shown in Figure 4, a gap (of the air layer) 28 is maintained by a fuze collar 13 on the lower side of the first and second cup elements 20 and 30, and since the majority of independent projections 27 are arranged on the first cup element 20, the gap (of the air layer) 28 is likewise maintained on the upper side of the first and second cup elements 20 and 30.

[0105] Thus, even if the second cup element 30 is inclined due to the absorption of pressure including heat from the outside, the distance of the gap (the air layer) 28 is maintained and a heat insulation function is shown. <Gas-Generator in Fig. 5>

[0106] A gas generator 100 of the present invention in Fig. 5 is the same as a well-known pyrotechnic dual-type gas generator (for example) Fig. 1 in JP 2011-207 326 A) except that the ignition device of the present disclosure is used therein.

[0107] A housing 101 is obtained by welding and integrating a diffuser sleeve 102, which has a gas delivery port 105 and a closure sleeve 103.

[0108] The gas outlet connection 105 is sealed from the outside by a sealing strip 106.

[0109] A cylindrical coolant filter 108 is positioned in the housing 101 at a distance from the gas outlet port 105.

[0110] The interior of the coolant filter 108 is a first combustion chamber 110, which is filled with a first gas generating agent 111.

[0111] A first ignition device chamber cup 113, which is provided with a through-hole 113a in a circumferential surface, is positioned in the first combustion chamber 110. A first igniter 112 and a gas-generating means 114 for an ignition device, which also functions as a transfer charge, are included in the first ignition device chamber cup 113.

[0112] The ignition device 1A of the present disclosure is positioned as a second combustion chamber in a space of the first combustion chamber 110, apart from the first ignition device chamber cup 113 and the first gas generating means 111.

[0113] Ignition device 1A is the same as ignition device 1, shown in (a) in Fig. 1, except that the attachment structure of the second cup element and the detonator collar are different.

[0114] In the ignition device 1A, a first cup element 120 is positioned so that it encloses an ignition section 141 of a detonator 140, and a second cup element 130 is positioned on the outside of the same with a gap (an air layer) 138. The first cup element 120 is pressed onto a smaller-diameter section 142 of a detonator collar.

[0115] The second cup element 130 is pressed into an intermediate diameter section 143 of the fuze collar, and an opening of the same is in contact with a base plate section 103a of the breech sleeve 103.

[0116] In Fig. 5 corresponds to the base plate section 103a of the breech sleeve 103, the larger diameter section 16 of the fuze collar 13 in (a) in Fig. 1.

[0117] The interior of the first cup element 120 is a second combustion chamber and is filled with a second gas generating agent 150.

[0118] Although not detailed in Fig. As shown in Figure 5, the first opening device of the first cup element 120 can be any of those shown in (a) in Fig. 1, (b) and (c) in Fig. 2, as shown, and the second opening device of the second cup element 130 can be any of those in (a) in Fig. 1, (a) and (b) in Fig. 3 shown.

[0119] Next, the operation of the gas generator 100 will be carried out in Fig.5, which is used as a gas generator for an automotive airbag device, is described in the case that the first igniter 112 is activated first and the second igniter 140 is activated with a delay.

[0120] When the first igniter 112 is activated, the gas generating agent 114 for the ignition device in the first ignition device chamber cup 113 is ignited and burns, and a combustion gas is produced.

[0121] The high-temperature combustion gas flows into the first combustion chamber 110 through the through-hole 113a to ignite and burn the first gas-generating agent 111 to produce a combustion gas.

[0122] The combustion gas generated in the first combustion chamber 110 passes through the coolant filter 108, then tears a sealing band 106 and is released from the gas delivery port 105 to deploy an airbag.

[0123] When the first gas-generating means 111 is ignited and combusted, producing combustion gas, the interior of the first combustion chamber 110 is at a high temperature. Consequently, the area surrounding the ignition device 1A is also at a high temperature, and in particular, the second cup element 130 is in contact with the combustion gas and any combustion residue is at a high temperature. At this point, since the second opening device of the second cup element 130 is closed from the outside by a sealing band, a sealing cup, or the like, the second opening device is not torn.

[0124] Due to the heat insulation function of a gap (an air layer) 138 between the second cup element 130 and the first cup element 120, heat is hardly transferred from the second cup element 130 to the first cup element 120.

[0125] This suppresses a temperature increase within the first cup element 120 and prevents a misfire of the second gas generating agent 150.

[0126] When the second igniter 140 is activated with a slight delay after the activation of the first igniter 112, the second gas-generating agent 150 is ignited and burns, and a combustion gas is produced.

[0127] The combustion gas generated in the first cup element 120 passes through the through-holes of the first cup element 120 to flow into the gap (the air layer) 138, and then passes through the through-holes of the second cup element 130 to flow into the first combustion chamber 110.

[0128] The combustion gas then passes through the coolant filter 108 and is then discharged from the open gas discharge port 105 to further deploy the airbag. As described above, when the ignition device of the present disclosure is used as the second combustion chamber of a pyrotechnic dual-type gas generator according to the invention, the sealing cup 37 or the sealing strip 36, which closes the through-holes 35, is positioned on the outside of the circumferential wall 32, so that the second opening device is open only when the combustion pressure of the second gas generating means 150 is applied.

Claims

[1] A gas generator comprising, a housing (101) which has a gas outlet connection (105), a first combustion chamber (110) filled with a first gas generating agent (111) and a second combustion chamber filled with a second gas generating agent (150); a first igniter (112) for the first combustion chamber (110), which is received in the housing (101) with a first igniter chamber cup (113), an igniter (1A) with a second igniter (140) for the second combustion chamber, which is received in the housing (101) with a first cup element (120), wherein the second detonator (140) is fixed to a detonator collar; the first cup element (120) has a bottom surface and a circumferential wall, and is filled with the second gas generating agent (150), the first cup element (120) covers the detonator collar, so that a section containing an ignition section (141) of the detonator (140) is enclosed, the first cup element (120) has a first opening device, characterized by that the ignition device (1A) with the second igniter (140) is positioned in a space of the first combustion chamber (110), and with a second cup element (130), which has a floor area and a perimeter wall, is provided for, the second cup element (130) covers the detonator collar, so that the first cup element (120) is enclosed, a gap (138) is formed between an outer surface on the bottom surface and the circumferential wall of the first cup element (120) and an inner surface on the bottom surface and the circumferential wall of the second cup element (130), and forms an air layer to function as a heat insulation layer, the second cup element (130) has a second opening device, and at least one of the first opening device and the second opening device is closed before activation, and is only opened when gas is generated by the gas generating component (150) of the ignition device (1A). [2] The gas generator according to claim 1, characterized by, that the first cup element (120) and the second cup element (130) of the ignition device (1A) are arranged such that a first projection formed on the outer surface of the first cup element (120) abuts the inner surface of the second cup element (130), or a second projection formed on the inner surface of the second cup element (130) abuts the outer surface of the first cup element (120). [3] The gas generator according to claim 1 or 2, characterized by , that the first cup element (120) of the ignition device (1A) is made of a material that has a lower thermal conductivity than the second cup element (130) of the ignition device (1A). [4] The gas generator according to claim 1 or 2, characterized by , that the first cup element (120) of the ignition device (1A) is made of a resin and the second cup element (130) of the ignition device (1A) is made of a metal. [5] The gas generator according to any one of claims 1 to 4, characterized by , that the detonator collar of the detonator (1A) has a metal section and a low-thermally conductive section made of a material having a lower thermal conductivity than the material of the metal section, and an opening of the first cup element (120) of the detonator (1A) and an inner circumferential wall at the opening of the same are in contact with the low-thermally conductive section. [6] The gas generator according to any one of claims 1 to 4, characterized by , that the detonator collar of the detonator (1A) has a smaller diameter section (14), an intermediate diameter section (15) and a larger diameter section (16), arranged from the detonator section (141) in ascending order in this order of outer diameters, The larger-diameter section (16) is made of metal, and at least the smaller-diameter section (14) includes a low-thermally conductive section made of a material that has a lower thermal conductivity than the metal of the metal section. A first circumferential surface (14b) is formed between the smaller-diameter section (14) and the intermediate-diameter section (15), obtained by a difference in their outer diameters, and a second circumferential surface (15a) is formed between the intermediate-diameter section (15) and the larger-diameter section (16), obtained by a difference in their outer diameters, and The first cup element (120) of the ignition device (1A) has an opening that abuts the first circumferential surface (14b), and an inner circumferential wall at the opening is pressed into the smaller diameter section (14). [7] The gas generator according to any one of claims 1 to 6, characterized by , that the opening amount of the gap (138) is in the range of 0.5 to 2.0 mm.

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