Gas generator

Abstract

A gas generator is provided with: a housing; and an igniter assembly defining, together with the housing, an accommodation space in which the gas source is accommodated, the igniter assembly having: an igniter; a collar member; a resin member integrally joining the igniter and the collar member; and a metal cover member configured so as to surround the ignition unit and the resin member so as to seal the igniter and the resin member with respect to the accommodation space, the cover member being welded to the collar member so as to extend across the boundary line between the resin member and the collar member when the igniter is cracked during operation.

Description

Technical Field

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

[0002] In the past, the following gas generator is well known: a gas source is accommodated in a storage space formed in a housing, and the gas is discharged to the outside by operating an igniter (for example, Patent Document 1). This gas generator is used, for example, to supply gas to an air bag or a seat belt retractor. As an igniter for a gas generator, an electric igniter that mainly operates by an ignition current is known. In a gas generator using an electric igniter, the following structure is generally adopted: an igniter assembly is formed by integrally joining an electric igniter and a metal collar member via a resin member, and the igniter assembly is mounted in a mounting hole formed in the housing.

[0003] Prior art literature

[0004] Patent Literature

[0005] Patent Document 1: U.S. Patent Application Publication No. 2012 / 234839

[0006] Patent document 2: German Patent Application Publication No. 102013110810 Summary of the invention

[0007] Problems to be solved by the invention

[0008] Here, from the viewpoint of stabilizing the performance of the gas generator, it is preferred to maintain airtightness of the storage space containing the gas source relative to the outside. However, in conventional gas generators, moisture may intrude into the storage space through the boundary between the collar member and the resin member, or the gas source may leak to the outside of the storage space.

[0009] The technology disclosed in the present invention has been made in view of the above-mentioned problems, and an object of the present invention is to provide a technology capable of improving the airtightness (sealing property) of a storage space for storing a gas source in a gas generator.

[0010] Solutions for solving problems

[0011] In order to solve the above-mentioned problems, the technology disclosed in the present invention adopts the following structure. That is, the technology disclosed in the present invention is a gas generator, comprising: a housing, which is formed with an igniter mounting hole; and an igniter assembly, which is installed on the housing in a manner of blocking the igniter mounting hole, and together with the housing, defines a storage space for storing a gas source, the igniter assembly has an igniter, a collar member, a resin member and a cover member, wherein the igniter includes: an ignition portion, which is formed with an ignition chamber for storing explosive; and a conductive portion, which is supplied with an ignition current for igniting the explosive, the igniter is configured so that the ignition portion is located on the inner side of the storage space than the conductive portion, and the igniter is configured to work by supplying an ignition current to the conductive portion, thereby the ignition portion is opened The igniter is provided with a hollow cylindrical body and a hollow cylindrical body, and the hollow body is provided with ...

[0012] Furthermore, in the gas generator of the present disclosure, a gas generating agent and a pressurized gas may be accommodated in the accommodation space as the gas source.

[0013] Furthermore, in the gas generator of the present disclosure, the cover member may be formed so as to ensure a space between a cleavage portion, which is a portion where the ignition portion cleaves, and the cover member.

[0014] In addition, in the gas generator disclosed in the present invention, the ignition part may also include: a cup body, including a cylindrical peripheral wall portion and a cover wall portion that closes one end of the peripheral wall portion and forms the rupture portion; and a closing member, configured to close the opening formed at the other end of the peripheral wall portion, and define the ignition chamber together with the cup body, and the ignition part is configured so that when the igniter is working, the cover wall portion is cracked, thereby discharging the combustion products of the detonator to the outside of the ignition chamber, and the cover member includes: a cylindrical peripheral wall opposing portion, configured to be opposite to the peripheral wall portion and in contact with the peripheral wall portion; and a dome-shaped cover wall opposing portion, formed to be opposite to the cover wall portion and protrude toward the accommodating space side.

[0015] In addition, in the gas generator disclosed in the present invention, the ignition part may also include: a cup body, including a cylindrical peripheral wall portion and a cover wall portion that closes one end of the peripheral wall portion and forms the rupture portion; and a closing member, configured to close the opening formed at the other end of the peripheral wall portion, and define the ignition chamber together with the cup body, and the ignition part is configured so that when the igniter is working, the cover wall portion is cracked to discharge the combustion product of the explosive, and the ignition part also has a cylindrical retaining bracket, and the retaining bracket is arranged in the ignition chamber in a manner of surrounding the explosive while being opposite to and in contact with the peripheral wall portion.

[0016] In addition, in the gas generator disclosed in the present invention, the ignition part may also include: a cup body, including a cylindrical peripheral wall portion and a cover wall portion that closes one end of the peripheral wall portion and forms the cleavage portion; and a closing member, configured to close the opening formed at the other end of the peripheral wall portion, and define the ignition chamber together with the cup body, and the ignition part is constructed so that when the igniter is working, the cover wall portion cracks to discharge the combustion products of the detonator, and the cover wall portion cracks in a manner that the combustion products are concentrated and radiated relative to the cover member, thereby the cover member cracks.

[0017] In addition, in the gas generator disclosed in the present invention, the ignition part may also include: a cup body, including a cylindrical peripheral wall portion and a cover wall portion that closes one end of the peripheral wall portion and forms the cleavage portion; and a closing member, configured to close the opening formed at the other end of the peripheral wall portion, and define the ignition chamber together with the cup body, and the ignition part is constructed so that when the igniter is working, the cover wall portion cracks to discharge the combustion products of the explosive, and the cover wall portion cracks in a manner that contacts the cover member, thereby the cover member cracks.

[0018] Furthermore, in the gas generator of the present disclosure, the collar member may be welded to the housing over its entire circumference.

[0019] Beneficial Effects

[0020] According to the present disclosure, the airtightness of the accommodation space accommodating the gas source in the gas generator can be improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 This is a cross-sectional view showing the state of the gas generator according to Embodiment 1 before operation.

[0022] Figure 2 This is a cross-sectional view showing the state of the vicinity of the igniter assembly before the gas generator of Embodiment 1 is operated.

[0023] Figure 3This is a plan view of the inner cup of the cup body according to the first embodiment.

[0024] Figure 4 This is a cross-sectional view showing a state of the vicinity of the igniter assembly when the gas generator according to Embodiment 1 is operated and the ignition portion is ruptured.

[0025] Figure 5 This is a cross-sectional view showing a state of the vicinity of the igniter assembly when the gas generator according to Embodiment 1 is operated and the cover member is ruptured.

[0026] Figure 6 This is a cross-sectional view showing the vicinity of the igniter assembly before the gas generator according to Modification 1 of Embodiment 1 is operated.

[0027] Figure 7 This is a cross-sectional view showing a state of the vicinity of the igniter assembly when the gas generator according to Modification 1 of Embodiment 1 is operated and the cover member is ruptured.

[0028] Figure 8 This is a cross-sectional view showing a state near the igniter assembly before the gas generator according to Modification 2 of Embodiment 1 is operated.

[0029] Fig. 9 This is a cross-sectional view showing the state of the vicinity of the igniter assembly before the gas generator of Embodiment 2 is operated. DETAILED DESCRIPTION

[0030] Hereinafter, the embodiments of the present disclosure will be described with reference to the accompanying drawings. The embodiments described below illustrate a scheme for applying the technology of the present disclosure to a gas generator (inflator) for an airbag. However, the use of the technology of the present disclosure is not limited thereto, and for example, it can also be applied to a gas generator for a seat belt retractor. It should be noted that each structure and their combination in each embodiment is an example, and the addition, omission, replacement and other changes of the structure can be appropriately made without departing from the scope of the main purpose of the present invention. The present disclosure is not limited to the embodiments, but only to the claims. It should be noted that in this specification, "full-circumference welding" refers to a continuous annular welding in the circumferential direction, which means that the gap generated between the two components to be welded is in a closed state.

[0031] <Implementation Method 1>

[0032] Figure 1 1 is a cross-sectional view showing a state of a gas generator for an air bag (hereinafter referred to as a gas generator) 100 before operation according to Embodiment 1. Figure 1, a cross section along the axial direction of the housing indicated by reference numeral 1 is shown. The gas generator 100 of the present embodiment is configured as a so-called single-type gas generator having one igniter. In addition, the gas generator 100 is also configured as a so-called mixed-type gas generator using a gas generating agent and pressurized gas as a gas source. However, the technology disclosed in the present invention is not limited to this. That is, the gas generator disclosed in the present invention may also have a plurality of igniters. In addition, the gas generator disclosed in the present invention may be configured as a so-called pyrotechnic-type gas generator using only a gas generating agent as a gas source, or may be configured as a so-called storage-type gas generator using only a pressurized gas as a gas source.

[0033] [Overall composition]

[0034] like Figure 1 As shown, the gas generator 100 includes: a cylindrical housing 1, which is formed with an igniter mounting hole 111; and an igniter assembly 2, which is installed on the housing 1 in a manner of blocking the igniter mounting hole 111. A storage space 10 is defined by the housing 1 and the igniter assembly 2. A gas generating agent 20 and a pressurized gas as a gas source are stored in the storage space 10. In addition, the gas generator 100 also includes a retaining frame 7, which is arranged in the storage space 10 in a manner of surrounding the igniter assembly 2 and the gas generating agent 20. Here, the direction along the axial direction of the housing 1 is defined as the up and down direction of the gas generator 100, and the igniter assembly 2 side (i.e. Figure 1 The lower side of the gas generator 100 is set as the lower side, and the opposite side (i.e. Figure 1 The upper side in the figure and the diffuser portion side indicated by the reference numeral 12 is set as the upper side of the gas generator 100.

[0035] The gas generator 100 is, for example, an inflator for an airbag, and is a device that supplies working gas for inflating an airbag (not shown) to the airbag when in operation. The gas generator 100 operates the igniter 3 included in the igniter assembly 2 to burn the gas generating agent 20 filled in the storage space 10, and discharges the combustion gas as the combustion product to the outside of the housing 1 together with the pressurized gas, thereby inflating the airbag (not shown). The components of the gas generator 100 are described below.

[0036] [shell]

[0037] like Figure 1As shown, the housing 1 has a metal housing body 11, a diffuser portion 12, and a rupture plate 13. The housing body 11 is formed into a cylindrical shape with both ends opened. The opening of one end (lower end) of the housing body 11 is formed as an igniter mounting hole 111 for mounting the igniter assembly 2. In addition, the opening of the other end (upper end) of the housing body 11 is formed as a diffuser mounting hole 112 for mounting the diffuser portion 12. In addition, a filling hole 113 is formed on the side of the housing body 11 to connect the inside and the outside of the housing 1. The filling hole 113 is closed by a closing pin 114 in a state where the pressurized gas is filled in the storage space 10 through the filling hole 113.

[0038] like Figure 1 As shown, the diffuser portion 12 is formed into a bottomed cylindrical shape with a step. Specifically, the diffuser portion 12 has: a gas discharge portion 121, including a closed end portion of the diffuser portion 12; and an embedded portion 122, including an open end portion of the diffuser portion 12 and having a diameter larger than the diameter of the gas discharge portion 121. A gas discharge hole 14 is formed on the peripheral wall of the gas discharge portion 121 to connect the inside and the outside of the diffuser portion 12. In a state where the embedded portion 122 is embedded in the diffuser mounting hole 112 of the housing body 11 and the gas discharge portion 121 protrudes to the outside of the diffuser mounting hole 112, the embedded portion 122 is welded to the inner wall of the diffuser mounting hole 112 throughout the circumference, thereby joining the diffuser portion 12 to the housing body 11.

[0039] like Figure 1 As shown, the rupture plate 13 is a plate-shaped member that separates the internal space of the housing body 11 from the internal space of the diffuser 12. The internal space of the housing body 11 and the internal space of the diffuser 12 are separated by the rupture plate 13, whereby the internal space of the diffuser 12 is maintained at a normal pressure. The rupture plate 13 is joined to the diffuser 12 by welding its peripheral edge to the stepped surface of the diffuser 12 over the entire circumference.

[0040] [Accommodation space]

[0041] The storage space 10 is formed as a space surrounded by the shell body 11 and the rupture plate 13 of the shell 1 and the igniter assembly 2. The gas generator 20 contained in the storage space 10 is burned by the operation of the igniter 3 to generate combustion gas. For the gas generator 20, for example, a solid gas generator with a relatively low combustion temperature is used. The combustion temperature of the gas generator 20 is, for example, 1000°C to 1700°C. The gas generator 20 can use, for example, a single-hole cylindrical substance composed of guanidine nitrate (41% by weight), basic copper nitrate (49% by weight), a binder, and an additive. In addition, for the pressurized gas contained in the storage space 10, for example, a pressurized gas composed of an inert gas monomer such as argon or helium or a mixture thereof is used. However, the gas generator 20 and the pressurized gas are not limited to the above-mentioned substances.

[0042] like Figure 1 As shown, a retainer 7 for retaining the gas generating agent 20 near the igniter assembly 2 is arranged in the storage space 10. The retainer 7 is a bottomed cylindrical member extending in the up-down direction and having its upper end closed, and is arranged to surround the igniter assembly 2 mounted in the igniter mounting hole 111. As a result, the storage space 10 is divided into a combustion chamber 10a inside the retainer 7 and a pressurized gas chamber 10b outside the retainer 7. The gas generating agent 20 is arranged in the combustion chamber 10a formed around the igniter assembly 2. It should be noted that a connecting hole 71 of a size that the gas generating agent 20 cannot pass through is formed in the retainer 7, and the combustion chamber 10a and the pressurized gas chamber 10b are connected via the connecting hole 71. Therefore, pressurized gas exists in both the combustion chamber 10a and the pressurized gas chamber 10b. That is, the entire storage space 10 including the combustion chamber 10a and the pressurized gas chamber 10b is filled with pressurized gas, and the entire storage space 10 is in a pressurized state.

[0043] [Ignitor assembly]

[0044] Figure 2 2 is a cross-sectional view showing the state of the vicinity of the igniter assembly 2 before the gas generator 100 of the first embodiment is operated. Figure 2 As shown, igniter assembly 2 includes igniter 3 , collar member 4 , resin member 5 , and metal cover member 6 .

[0045] [Ignition]

[0046] like Figure 2 As shown, the igniter 3 includes an ignition portion 31 and a pair of conductive pins 32, 32. An ignition chamber 314 for accommodating explosive is formed in the ignition portion 31. An ignition current for igniting the explosive accommodated in the ignition chamber 314 is supplied to the pair of conductive pins 32, 32. The pair of conductive pins 32, 32 is an example of a "conductive portion" of the present disclosure. The igniter 3 is configured as an electric igniter. In a specific example, the igniter 3 is operated by the ignition current supplied to the pair of conductive pins 32, 32, whereby the ignition portion 31 is cracked and the combustion product of the explosive is discharged. Figure 2 As shown, the igniter 3 is arranged so that the ignition portion 31 is located closer to the inner side of the accommodation space 10 (the side closer to the accommodation space 10 ) than the pair of conductive pins 32 , 32 .

[0047] like Figure 2As shown, the ignition part 31 has a cup body 311, a metal head 312 (an example of the "blocking member" of the present disclosure) and a retaining bracket 313. The cup body 311 is formed into a bottomed cylindrical shape, and has a double structure formed by superimposing an outer cup 311b with insulation on the outer side of a metal inner cup 311a. The material of the outer cup 311b is not particularly limited, but a resin material can be exemplified. By sandwiching the outer cup 311b with insulation between the inner cup and the cover member 6, the current supplied to the housing 1 due to leakage or the like is prevented from flowing to the conductive pin 32 via the cover member 6, the inner cup 311a, and the metal head 312 (that is, accidental ignition of the gas generator 100). The cup body 311 is constructed to include a cylindrical peripheral wall portion 3111 and a cover wall portion 3112 that blocks one end (upper end) of the peripheral wall portion 3111. The cover wall portion 3112 is an example of the "cracking portion" of the present disclosure. The metal head 312 is a cylindrical metal member, and is arranged inside the cup body 311 so as to close the opening formed at the other end (lower end) of the peripheral wall portion 3111. The metal head 312 is welded to the inner wall of the peripheral wall portion 3111 over the entire circumference of its outer peripheral surface. Figure 2 As shown, an ignition chamber 314 for accommodating explosive is defined by the cup body 311 and the metal head 312. The retaining bracket 313 is formed in a cylindrical shape. The retaining bracket 313 is arranged in the ignition chamber 314 in a manner of surrounding the explosive while being opposed to and in contact with the peripheral wall portion 3111 of the cup body 311. By providing the retaining bracket 313, for example, it is easy to press-fill the explosive into the metal head 312. In addition, it is possible to prevent the contact state between the explosive and the bridge wire 315 described later from changing due to external pressure after the igniter 3 is assembled.

[0048] A pair of conductive pins 32, 32 extend downward from the ignition portion 31. One of the pair of conductive pins 32, 32 is joined to the metal head 312 via the insulator 316 while being inserted into the through hole of the metal head 312. The other of the pair of conductive pins 32, 32 is joined to the lower surface of the metal head 312. A connector (not shown) for supplying power from an external power source is connected to the pair of conductive pins 32, 32.

[0049] The igniter 3 is operated by power supplied to a pair of conductive pins 32, 32 via a connector. Here, a bridge wire 315 as a resistor that electrically connects the conductive pin 32 on one side to the metal head 312 is wired at the bottom of the ignition chamber 314. The current is supplied to the pair of conductive pins 32, 32 and flows through the bridge wire 315, and the Joule heat generated in the bridge wire 315 causes the explosive in the ignition chamber 314 to burn. Along with this, the pressure in the ignition chamber 314 rises, thereby the cover wall portion 3112 of the cup body 311 is cracked, and the combustion product of the explosive is discharged to the outside of the ignition chamber 314.

[0050] Figure 3 1 is a plan view of the inner cup 311 a of the cup body 311 according to the first embodiment. Figure 3 The middle figure shows the upper end surface (closed end surface) of the inner cup 311a of the cover wall portion 3112 constituting the cup body 311. Figure 3 As shown in FIG. 1 , a plurality of grooves 3113 are formed on the upper end surface of the inner cup 311a and extend radially from the center portion. The plurality of grooves 3113 extend radially from the center portion of the upper end surface of the inner cup 311a. Figure 3 As shown, in this example, eight grooves 3113 are formed at equal angles. However, the technology disclosed in the present invention is not limited thereto. The portion of the upper end of the inner cup 311a where the grooves 3113 are formed is thinner than other portions, and is therefore more fragile than the other portions and more likely to break than other portions. As a result, the cover wall portion 3112 is more likely to crack when the igniter 3 is in operation.

[0051] [Ring member]

[0052] like Figure 2 As shown, the collar member 4 is a metal cylindrical member, which is configured to surround the igniter 3 and support the igniter 3 via the resin member 5. The collar member 4 has: a first portion 41 including the lower end of the collar member 4; a second portion 42 connected to the upper end of the first portion 41 and having an outer diameter smaller than the outer diameter of the first portion 41; and a third portion 43 connected to the upper end of the second portion 42 and including the upper end of the collar member 4, and having an outer diameter smaller than the outer diameter of the second portion 42. Thus, a step is formed on the outer periphery of the collar member 4.

[0053] like Figure 2 As shown, with the second portion 42 and the third portion 43 of the collar member 4 inserted into the igniter mounting hole 111 of the housing 1, the upper end surface of the first portion 41 is welded to the lower end surface of the housing body 11 around the entire circumference, thereby joining the collar member 4 to the housing 1. Figure 2 Reference symbol W1 indicates a welded portion between the collar member 4 and the housing 1. In this way, the igniter assembly 2 is inserted into the igniter mounting hole 111 in a manner that blocks the igniter mounting hole 111, and the collar member 4 is continuously welded (i.e., welded all around) to the housing 1 to be mounted on the housing 1. Furthermore, in a state where the third portion 43 of the collar member 4 is embedded in the opening formed at the lower end of the retainer 7, the outer peripheral surface of the second portion 42 is welded all around to the inner peripheral surface of the retainer 7, thereby joining the retainer 7 to the igniter assembly 2. Figure 2 Reference symbol W2 denotes a welding portion between the collar member 4 and the retainer 7 .

[0054] [Resin components]

[0055] like Figure 2As shown, the resin member 5 is a member made of resin, which is arranged between the igniter 3 and the collar member 4 and integrally joins the igniter 3 and the collar member 4. The resin member 5 is configured to fill the annular gap formed between the igniter 3 and the collar member 4. At this time, the resin member 5 covers the igniter 3 in such a manner that the cover wall portion 3112, a part of the peripheral wall portion 3111, and the top ends of a pair of conductive pins 32, 32, which are the cracked parts in the ignition portion 31, are exposed from the resin member 5. In addition, the resin member 5 covers the inner circumferential surface of the collar member 4 in such a manner that a connector insertion space 51 is formed on the inner side of the collar member 4 as a space into which a power supply connector can be inserted. In addition, in this example, the resin member 5 covers the upper end surface of the third portion 43 in such a manner that its outer circumferential surface is located on the same plane as the outer circumferential surface of the third portion 43 of the collar member 4.

[0056] [Border Department]

[0057] Here, Figure 2 The dotted line indicated by the reference numeral B1 in the figure indicates a boundary portion as a joining portion between the collar member 4 and the resin member 5. The boundary portion B1 is formed by the mutual joining surfaces of the collar member 4 and the resin member 5. Figure 2 As shown, the boundary portion B1 extends from the outside to the inside of the housing 1. Here, the member formed by integrating the collar member 4 and the resin member 5 is set as the joint body 21. At this time, the end of the boundary portion B1 is presented on the surface of the joint body 21 as the boundary line between the collar member 4 and the resin member 5. Figure 2 In FIG. 1 , the end of the boundary line between the collar member 4 and the resin member 5 that is present inside the housing 1 is indicated by a reference symbol B11. The boundary line B11 is located on the outer peripheral surface of the bonded body 21.

[0058] [Cover member]

[0059] The cover member 6 is a metal member, which is configured to surround the ignition portion 31 and the resin member 5 in a manner that the igniter 3 and the resin member 5 are sealed relative to the storage space 10 before the igniter 3 is operated, and is cracked when the igniter 3 is operated. The metal material forming the cover member 6 is not particularly limited, but examples thereof include stainless steel, aluminum, iron, etc. Figure 2 As shown, the cover member 6 is formed substantially in a bottomed cylindrical shape and has an axially extending portion 61 , a radially extending portion 62 , a peripheral wall facing portion 63 , and a cover wall facing portion 64 .

[0060] The axially extending portion 61 is formed into a cylindrical shape extending in the vertical direction. The axially extending portion 61 covers the outer peripheral surface of the third portion 43 of the collar member 4 and the outer peripheral surface of the resin member 5 in a manner straddling the boundary line B11 between the collar member 4 and the resin member 5, and is welded to the outer peripheral surface of the third portion 43 throughout the circumference. Figure 2The reference numeral W3 in the figure represents the welding portion between the cover member 6 and the collar member 4. The cover member 6 and the collar member 4 are continuously welded in a manner throughout the entire circumference at a position exposed to the accommodating space 10, and the welding portion W3 is exposed to the pressurized gas. Therefore, the end of the boundary line B11 between the collar member 4 and the resin member 5 is not exposed to the accommodating space 10, and is not connected to the accommodating space 10. The radial extension portion 62 extends radially inward from the upper end of the axial extension portion 61, covering the upper end surface of the resin member 5. The peripheral wall opposing portion 63 is formed into a cylindrical shape extending upward from the inner end of the radial extension portion 62, covering the outer peripheral surface of the peripheral wall portion 3111 of the cup body 311. That is, the peripheral wall opposing portion 63 is configured in a state of being opposed to and in contact with the peripheral wall portion 3111 of the cup body 311. It should be noted that the peripheral wall opposing portion 63 may not be in contact with the peripheral wall portion 3111 all around, or a portion of the peripheral wall opposing portion 63 may be in contact with the peripheral wall portion 3111 in the circumferential direction. The cover wall opposing portion 64 is formed in a dome shape (hemispherical shape) that blocks the upper end of the peripheral wall opposing portion 63 and protrudes toward the upper side (the accommodating space 10 side) before the gas generator 100 operates. The cover wall opposing portion 64 is opposed to the cover wall portion 3112 of the cup body 311, and a predetermined space S1 is formed between the cover wall portion 3112. The cover wall opposing portion 64 is formed with a uniform thickness as a whole.

[0061] When the igniter 3 is working, the pressure of the combustion products of the explosive discharged from the ignition part 31 to the specified space S1 causes the cover wall opposing part 64 to crack, thereby opening the cover member 6. A groove for promoting the proper cracking of the cover wall opposing part 64 may also be formed in the cover wall opposing part 64. The groove may, for example, be a groove extending radially from the top of the cover wall opposing part 64 as a starting point. It should be noted that the cover member 6 itself may not crack. In the cover member 6 of the present embodiment, no hole is formed, but, for example, a through hole may be formed in the cover member 6, and a closed state may be formed by closing the through hole with a closing member. In this case, it is also possible that the closing member is cracked by the pressure of the combustion products when the igniter 3 is working, thereby opening the cover member 6.

[0062] like Figure 2As shown, by welding the cover member 6 to the collar member 4 all around, before the igniter 3 works, the igniter 3, the resin member 5 and the specified space S1 surrounded by the cover member 6 are sealed relative to the storage space 10. Therefore, the specified space S1 is maintained at normal pressure. Moreover, the cover member 6 is welded to the collar member 4 all around in a manner that crosses the boundary line B11, so that the end of the boundary portion B1 between the resin member 5 and the collar member 4 will not be exposed to the storage space 10. Therefore, before the igniter 3 works, the boundary portion B1 is sealed relative to the storage space 10. As a result, moisture is prevented from invading the interior of the storage space 10 from the outside of the gas generator 100 through the boundary portion B1, or pressurized gas is prevented from leaking from the storage space 10 to the outside of the gas generator 100 through the boundary portion B1. That is, the fluid (moisture, gas) is prevented from flowing into / out of the storage space 10 via the boundary portion B1. In addition, as described above, the igniter 3 and the resin member 5 are also sealed relative to the storage space 10, so the inflow / outflow of the fluid through the boundary between the igniter 3 and the resin member 5 is also prevented. For example, in the case where the igniter 3 and the collar member 4 are integrated by the resin member 5 formed by injection molding, due to the shrinkage of the resin during solidification, a gap may be generated at the boundary B1 between the resin member 5 and the collar member 4, and the boundary between the igniter 3 and the resin member 5. Even in the case where such a gap is generated, the gas generator 100 can prevent the fluid from flowing into / out of the storage space 10 through the gap. Moreover, in the gas generator 100 of the present embodiment, the collar member 4 is welded to the housing 1 all around, so the inflow / outflow of the fluid through the boundary between the housing 1 and the collar member 4 is also prevented. As a result, in the gas generator 100 of the present embodiment, before the igniter 3 is operated, the storage space 10 is maintained airtight relative to the outside of the gas generator 100.

[0063] In addition, when the storage space 10 is filled with pressurized gas as in this example, the cover member 6 functions as a protective device for protecting the igniter 3 from the high pressure. Assuming that the cover member 6 does not exist and the ignition part 31 of the igniter 3 is exposed to the pressurized gas, the contact state between the bridge wire 315 arranged in the ignition chamber 314 and the detonator may be deteriorated due to the deformation of the cup body 311. In such a case, the following situation may occur: the ignition performance expected as the igniter 3 cannot be obtained, and the external diagnostic circuit judges that it is wrong and the igniter 3 does not work. The gas generator 100 of this embodiment can prevent such a situation by having a cover member 6.

[0064] In addition, as described later, the prescribed space S1 is a space for making the cover wall portion 3112 of the cup body 311 easy to crack when the igniter 3 is working. In the gas generator 100 of the present embodiment, the cover wall opposing portion 64 of the cover member 6 for forming the prescribed space S1 between the cover wall portion 3112 is set to a dome shape with rounded corners, thereby giving the cover wall opposing portion 64 strength (pressure resistance) to resist pressurized gas. Therefore, it is possible to suppress the deformation of the cover wall opposing portion 64 due to pressurized gas before the igniter 3 is working. In addition, the cover wall opposing portion 64 can be thinned so that the cover wall opposing portion 64 is easy to crack when the igniter 3 is working.

[0065] Here, if the ease of deformation against the pressurized gas is compared according to each part of the cover member 6, there is a tendency that the cylindrical peripheral wall opposing portion 63 is easier to deform than other parts. In response to this, in the gas generator 100 of the present embodiment, the peripheral wall opposing portion 63 is arranged in a state of being opposed to and in contact with the peripheral wall portion 3111 of the cup body 311. Moreover, in the ignition chamber 314, the cylindrical retaining bracket 313 is arranged in a state of being opposed to and in contact with the peripheral wall portion 3111. As a result, the peripheral wall opposing portion 63 of the cover member 6 is in a state of being supported by the peripheral wall portion 3111 of the cup body 311 and the retaining bracket 313 relative to the pressurized gas. As a result, the peripheral wall opposing portion 63 can be suppressed from being deformed by the pressurized gas before the igniter 3 works.

[0066] In addition, if Figure 2 As shown, the cover member 6 is in a state where the other parts except the cover wall facing portion 64 are in contact with and supported by any one of the igniter 3, the collar member 4, and the resin member 5. Therefore, the cover member 6 can be more appropriately prevented from being deformed by the pressurized gas before the igniter 3 is operated.

[0067] It should be noted that, in the technology disclosed in the present invention, the cover wall opposing portion of the cover member may not be dome-shaped, and the cover wall opposing portion may be in contact with the cover wall portion of the cup body. That is, the cover wall opposing portion may cover the cover wall portion, and space may not be ensured between the cover wall portion and the cover member, so that the cover member as a whole is in contact with any one of the igniter, the collar member, and the resin member. In addition, in the technology disclosed in the present invention, the peripheral wall opposing portion of the cover member may not be in contact with the peripheral wall portion of the cup body. It is also possible that the cover member does not contact the collar member except for the welding portion with the collar member. In addition, it is also possible that the peripheral wall opposing portion 63 does not exist in the cover member 6, and the dome-shaped cover wall opposing portion 64 is connected to the radial inner end of the radial extension portion 62.

[0068] [action]

[0069] Next, the operation of the gas generator 100 according to the first embodiment will be described. Figure 1 and Figure 2In the state where the gas generator 100 before operation is mounted on the vehicle, the connector (not shown) inserted into the connector insertion space 51 is connected to the pair of conductive pins 32, 32 of the igniter 3, and power can be supplied to the igniter 3. In this state, when a sensor (not shown) mounted on the vehicle senses an impact, power from an external power source (not shown) is supplied to the pair of conductive pins 32, 32 via the connector, thereby the igniter 3 is operated and the explosive in the ignition chamber 314 is burned.

[0070] Figure 4 1 is a cross-sectional view showing the state of the vicinity of the igniter assembly 2 when the gas generator 100 of the first embodiment is in operation and the ignition portion 31 is ruptured. When the pressure in the ignition chamber 314 increases as the explosive burns, as shown in FIG. Figure 4 As shown, the cover wall portion 3112 of the cup body 311 is cracked, and the combustion product of the detonator is discharged from the ignition portion 31 to the specified space S1. At this time, since the specified space S1 is ensured between the cover wall portion 3112 and the cover member 6, the cracking of the cover wall portion 3112 is prevented from being blocked by the cover member 6. Therefore, the cover wall portion 3112 is easy to crack.

[0071] When the pressure in the specified space S1 rises due to the combustion products discharged from the ignition part 31, the cover wall opposing portion 64 of the cover member 6 cracks, and the combustion products of the explosive are discharged into the combustion chamber 10a of the accommodating space 10. Here, as described above, a plurality of grooves 3113 extending radially from the center portion thereof are formed on the upper end surface of the inner cup body 311a of the cover wall portion 3112 constituting the cup body 311. Therefore, the cover wall portion 3112 cracks in a petal shape from the center portion thereof. At this time, the flow of the combustion products discharged from the ignition part 31 corresponds to the cracking angle θ of the cracked pieces of the cover wall portion 3112. The cracking angle θ can be, for example, Figure 4 The angle θ of the split piece relative to the plane orthogonal to the axial direction of the peripheral wall portion 3111 is defined as shown. In the gas generator 100 of the present embodiment, the plurality of grooves 3113 are formed so that the split angle θ of the split piece of the cover wall portion 3112 becomes less than a predetermined value. Figure 4 As shown, the combustion products of the detonator are discharged in a concentrated manner relative to the cover member 6 (more specifically, the cover wall opposing portion 64). As a result, the cover member 6 is easily cracked. In addition, in the gas generator 100 of this embodiment, in order to accelerate the pressure rise of the specified space S1, the volume of the specified space S1 is set to be less than a specified value. As a result, the cover member 6 is also easily cracked.

[0072] Figure 5This is a cross-sectional view showing the state of the vicinity of the igniter assembly 2 when the gas generator 100 of the first embodiment is in operation and the cover member 6 is ruptured. The combustion product of the detonator is discharged into the combustion chamber 10a of the storage space 10, thereby igniting the gas generating agent 20 arranged in the combustion chamber 10a. The combustion gas of the gas generating agent 20 flows into the pressurized gas chamber 10b through the connecting hole 71 formed in the retaining frame 7. In addition, when the pressure in the storage space 10 rises with the generation of the combustion gas, Figure 1 The rupture plate 13 shown is broken. As a result, the combustion gas generated by the combustion of the gas generating agent and the pressurized gas contained in the containing space 10 are discharged from the gas discharge hole 14 of the diffuser portion 12 to the outside of the gas generator 100. As a result, the airbag is inflated to protect the occupants of the vehicle from the impact.

[0073] [Effect]

[0074] As described above, the gas generator 100 of the first embodiment includes: a housing 1 formed with an igniter mounting hole 111; and an igniter assembly 2 mounted on the housing 1 in a manner of blocking the igniter mounting hole 111, and defining a storage space 10 for storing a gas source together with the housing 1. The igniter assembly 2 includes an igniter 3, a metal collar member 4, a resin member 5, and a metal cover member 6. The igniter 3 includes: an ignition portion 31 formed with an ignition chamber 314 for storing a primer; and a pair of conductive pins 32, 32 to which an ignition current for igniting the primer is supplied, and the igniter 3 is configured so that the ignition portion 31 is located on the inner side of the storage space 10 relative to the pair of conductive pins 32, 32. In addition, the igniter 3 is configured to operate by the ignition current supplied to the pair of conductive pins 32, 32, whereby the ignition portion 31 is ruptured to discharge the combustion product of the primer. The collar member 4 is formed into a cylindrical shape and is inserted into the igniter mounting hole 111 in a manner of surrounding the igniter 3. The resin member 5 is arranged between the igniter 3 and the collar member 4, and the igniter 3 and the collar member 4 are integrally joined in a state where the cover wall portion 3112 and a pair of conductive pins 32, 32, which are the cracked parts in the ignition portion 31, are exposed from the resin member 5. The cover member 6 is configured to surround the ignition portion 31 and the resin member 5 in a manner that makes the igniter 3 and the resin member 5 airtight relative to the storage space 10, and cracks when the igniter 3 is working. In addition, the cover member 6 is welded to the collar member 4 all around in a manner that straddles the boundary line B11 between the resin member 5 and the collar member 4. According to the gas generator 100 of embodiment 1 configured in this way, the airtightness of the storage space 10 that stores the gas source can be improved.

[0075] Furthermore, the collar member 4 of the gas generator 100 according to the first embodiment is welded to the housing 1 over the entire circumference. This can further improve the airtightness of the housing space 10.

[0076] Furthermore, cover member 6 of gas generator 100 according to Embodiment 1 is formed so as to ensure a predetermined space S1 between cover wall portion 3112 that is cleaved in ignition portion 31 and cover member 6. Thus, cover wall portion 3112 can be easily cleaved.

[0077] In gas generator 100 of Embodiment 1, gas generating agent 20 and pressurized gas as a gas source are stored in storage space 10. Gas generator 100 with improved airtightness of storage space 10 can suppress leakage of pressurized gas to the outside of gas generator 100.

[0078] In addition, the ignition part 31 of the gas generator 100 of the first embodiment has a cup body 311, and the cup body 311 includes a cylindrical peripheral wall portion 3111 and a cover wall portion 3112 that closes one end of the peripheral wall portion 3111. In addition, the ignition part 31 has a metal head 312, which is arranged in a manner to close the opening formed at the other end of the peripheral wall portion 3111, and defines an ignition chamber 314 together with the cup body 311. In addition, the ignition part 31 is configured so that when the igniter 3 is operated, the cover wall portion 3112 is ruptured, thereby discharging the combustion product of the detonator to the outside of the ignition chamber 314. Furthermore, the cover member 6 includes: a cylindrical peripheral wall facing portion 63 arranged to face and contact the peripheral wall portion 3111 of the cup body 311; and a dome-shaped cover wall facing portion 64 formed to face the cover wall portion 3112 of the cup body 311 and protrude toward the accommodating space 10. Thus, the peripheral wall facing portion 63 is supported by the peripheral wall portion 3111 of the cup body 311, and the pressure resistance of the cover wall facing portion 64 is improved, so that deformation of the cover member 6 caused by the pressurized gas before the igniter 3 is operated can be suppressed.

[0079] In addition, the ignition portion 31 of the gas generator 100 of the first embodiment further includes a cylindrical retaining bracket 313, which is arranged in the ignition chamber 314 so as to surround the detonator while being opposed to and in contact with the peripheral wall portion 3111 of the cup body 311. Thus, the peripheral wall opposing portion 63 of the cover member 6 is supported by the peripheral wall portion 3111 of the cup body 311 and the retaining bracket 313, so that deformation of the peripheral wall opposing portion 63 can be more appropriately suppressed.

[0080] In gas generator 100 of Embodiment 1, cover wall portion 3112 of ignition portion 31 is cleaved so that combustion products of the primary explosive are radiated intensively toward cover member 6 when igniter 3 is operated. Thus, cover member 6 can be easily cleaved.

[0081] [Modifications]

[0082] Hereinafter, a gas generator according to a modified example of the first embodiment will be described. Figure 1 to Figure 5The description will focus on the differences between the gas generator 100 described above, and detailed description of the same points as the gas generator 100 will be omitted.

[0083] [Modification 1]

[0084] Figure 6 1 is a cross-sectional view showing the state of the vicinity of the igniter assembly 2 before the gas generator 100A according to the first modification of the first embodiment is operated. Figure 7 1 is a cross-sectional view showing a state of the vicinity of the igniter assembly 2 when the gas generator 100A of the modification 1 of the embodiment 1 is in operation and the cover member 6A is ruptured. Figure 7 As shown, in the gas generator 100A of the first modification of the first embodiment, the cover wall portion 3112 of the cup body 311 is broken in such a way as to contact the cover member 6A when the igniter 3 is operated. Figure 6 and Figure 7 As shown, the cover member 6A of the modification example 1 is formed such that a predetermined space S1 is ensured between the cover member 6A and the cover wall portion 3112 before the igniter 3 is operated, and the cracked piece of the cover wall portion 3112 contacts the cover member 6A when the igniter 3 is operated. When the igniter 3 is operated, the cracked piece of the cover wall portion 3112 of the cup body 311 contacts the cover member 6A, thereby concentrating stress on the cover member 6A (the portion contacted by the cracked piece). As a result, the cover member 6A can be easily cracked.

[0085] [Modification 2]

[0086] Figure 8 1 is a cross-sectional view showing the state of the vicinity of the igniter assembly 2 before the gas generator 100B of the second modification of the first embodiment is operated. Figure 8 As shown, in the gas generator 100B of the modified example 2, the resin member 5 covers the inner circumferential surface of the collar member 4 in a manner that its upper end surface is located on the same plane as the upper end surface of the third portion 43 of the collar member 4. Therefore, the end of the boundary line B11 between the collar member 4 and the resin member 5 presented inside the housing 1 is located at the upper end surface of the joint 21 of the collar member 4 and the resin member 5. In addition, the cover member 6B of the modified example 2 does not have the above-mentioned axial extension portion 61. The radial extension portion 62 of the cover member 6B covers the upper end surface of the third portion 43 of the collar member 4 and the upper end surface of the resin member 5 in a manner that straddles the boundary line B11 between the collar member 4 and the resin member 5, and is continuously welded to the upper end surface of the third portion 43 in a manner that covers the entire circumference. In the gas generator 100B of such a modified example 2, the cover member 6B is welded to the collar member 4 in a manner that straddles the boundary line B11 between the resin member 5 and the collar member 4, so the airtightness of the accommodating space 10 can also be improved.

[0087] <Implementation Method 2>

[0088] Hereinafter, gas generator 100C according to Embodiment 2 will be described. Fig. 9 This is a cross-sectional view showing a state of gas generator 100C according to Embodiment 2 before operation. Fig. 9 100C of the gas generator of the second embodiment is a so-called pyrotechnic type gas generator that uses only a gas generating agent as a gas source. Figure 1 to Figure 5 The description will focus on the differences between gas generator 100 of the first embodiment described above, and detailed description of the same points as gas generator 100 will be omitted.

[0089] [constitute]

[0090] like Fig. 9 As shown in FIG. 1 , the gas generator 100C of the second embodiment includes a housing 1C, an igniter assembly 2, a filter 8, and an inner cylinder member 9. Figure 2 The igniter assembly 2 shown, but can also be replaced Figure 2 The igniter assembly 2 shown includes Figure 8 The igniter assembly 2 is shown.

[0091] like Fig. 9 As shown, the housing 1C of the second embodiment is formed into a short cylindrical shape with both ends in the axial direction closed by joining the upper shell 15 and the lower shell 16 made of metal, each formed into a bottomed cylindrical shape, with their open ends facing each other. However, the structure of the upper shell 15 and the lower shell 16 is not limited to this, and a known structure can be used as appropriate.

[0092] like Fig. 9 As shown, the upper shell 15 has: a cylindrical upper cylinder 151; a top plate 152 that closes the upper end of the upper cylinder 151; and a flange-shaped joint 153 that extends radially outward from the lower end of the upper cylinder 151. In addition, the lower shell 16 has: a cylindrical lower cylinder 161; a bottom plate 162 that closes the lower end of the lower cylinder 161; and a flange-shaped joint 163 that extends radially outward from the upper end of the lower cylinder 161. The joint 153 of the upper shell 15 and the joint 163 of the lower shell 16 are overlapped and joined by welding or the like, thereby forming the housing 1C.

[0093] A plurality of gas discharge holes 17 for communicating the inside and outside of the housing 1C are formed in parallel along the circumferential direction in the upper cylinder portion 151 of the upper case 15. Before the gas generator 100C is operated, the gas discharge holes 17 are closed by a closing member such as a sealing tape (not shown).

[0094] Furthermore, an igniter mounting hole 18 for mounting the igniter assembly 2 is formed in the bottom plate portion 162 of the lower housing 16. The igniter assembly 2 is mounted to the housing 1C by welding the collar member 4 to the housing 1C (more specifically, the inner wall of the igniter mounting hole 18) over the entire circumference while the igniter mounting hole 18 is inserted into the igniter mounting hole 18 so as to block the igniter mounting hole 18.

[0095] The filter 8 is a cylindrical member having multiple holes. Fig. 9 As shown in FIG. 1 , the filter 8 is arranged between the igniter assembly 2 and the gas discharge hole 17 in a state where the upper end portion is supported by the top plate portion 152 of the upper housing 15 and the lower end portion is supported by the bottom plate portion 162 of the lower housing 16. Thus, a storage space 10C for storing the gas source is formed between the housing 1C, the filter 8, and the igniter assembly 2. More specifically, the storage space 10C is formed as a space surrounded by the top plate portion 152 of the upper housing 15, the bottom plate portion 162 of the lower housing 16, the filter 8, and the igniter assembly 2.

[0096] like Fig. 9 As shown, the inner cylinder member 9 is a bottomed cylindrical member extending in the up-down direction and having its upper end blocked, and is configured to surround the igniter assembly 2 mounted in the igniter mounting hole 18. In a state where the collar member 4 of the igniter assembly 2 is fitted into the opening formed at the lower end of the inner cylinder member 9, the collar member 4 and the inner cylinder member 9 are welded all around, thereby the inner cylinder member 9 is joined to the igniter assembly 2. The accommodating space 10C is divided into a first combustion chamber 101 inside the inner cylinder member 9 and a second combustion chamber 102 outside the inner cylinder member 9 by the inner cylinder member 9. In addition, a plurality of communication holes 91 are formed in the inner cylinder member 9 to communicate the internal space of the inner cylinder member 9 (i.e., the first combustion chamber 101) with the external space (i.e., the second combustion chamber 102). Before the igniter 3 is operated, the communication holes 91 are blocked by a blocking member such as a sealing tape (not shown).

[0097] The first combustion chamber 101 contains a first gas generator 30 as a gas source, and the second combustion chamber 102 contains a second gas generator 40 as a gas source. The first gas generator 30 is burned by the operation of the igniter 3 to generate combustion gas. The first gas generator 30 functions as a so-called ignition agent for igniting the second gas generator 40. The second gas generator 40 is ignited by the combustion gas of the first gas generator 30 (ignition agent) burned by the operation of the igniter 3 to generate combustion gas. The first gas generator 30 and the second gas generator 40 can use the same gas generator as the gas generator 20 of the above-mentioned embodiment 1. However, the first gas generator 30 and the second gas generator 40 are not limited to the above-mentioned gas generators. In addition, the first gas generator 30 and the second gas generator 40 can be gas generators of the same type, shape, and size, or they can be gas generators of different types, shapes, and sizes.

[0098] The filter 8 is configured to allow the combustion gas to pass therethrough, and the combustion gas is cooled by passing through the filter 8. At this time, the filter 8 filters the combustion gas by collecting combustion residues of the combustion gas.

[0099] [action]

[0100] Next, the operation of the gas generator 100C of the second embodiment is described. The operation of the igniter 3 is the same as that of the first embodiment, so the description is omitted. When the igniter 3 is working, the ignition part 31 is cracked and the combustion product of the detonator is discharged. The cover member 6 is cracked due to the combustion product discharged from the ignition part 31, and the combustion product is discharged to the first combustion chamber 101 of the storage space 10. As a result, the first gas generator 30 (explosion-transmitting powder) contained in the first combustion chamber 101 burns to generate combustion gas. The combustion gas of the first gas generator 30 destroys the sealing tape that blocks the connecting hole 91 and is discharged from the connecting hole 91 to the second combustion chamber 102. Then, the second gas generator 40 is ignited by the combustion gas of the first gas generator 30, and the combustion gas of the second gas generator 40 is generated. After the combustion gas of the storage space 10C is cooled and filtered by passing through the filter 8, it destroys the sealing tape that blocks the gas discharge hole 17 and is discharged to the outside of the gas generator 100C. As a result, the airbag expands and protects the occupants of the vehicle from impact.

[0101] [Function / Effect]

[0102] In the gas generator 100C of the second embodiment, the same effect as that of the first embodiment can be achieved. That is, the cover member 6 is welded to the collar member 4 over the entire circumference in a manner that straddles the boundary line between the resin member 5 and the collar member 4, thereby preventing moisture from intruding into the interior of the storage space 10C through the boundary between the resin member 5 and the collar member 4 and the boundary between the igniter 3 and the resin member 5. As a result, according to the gas generator 100C of the second embodiment, the airtightness of the storage space 10C can be improved.

[0103] <Others>

[0104] The above is a description of the embodiments of the technology disclosed in the present invention, but the various schemes disclosed in the present invention may be combined with any other features disclosed in the present invention. In addition, in the above embodiments, the technology disclosed in the present invention is applied to a hybrid gas generator and a pyrotechnic gas generator as an example, but the technology disclosed in the present invention may also be applied to a so-called storage gas generator that uses only pressurized gas as a gas source. For example, the technology disclosed in the present invention may also be applied to a gas generator that discharges gas by rupturing a rupture plate using a shock wave, as disclosed in Japanese Patent Application Publication No. 2003-520153.

[0105] Description of Reference Numerals

[0106] 1: Shell (an example of a container);

[0107] 111: igniter mounting hole;

[0108] 2: Ignition assembly;

[0109] 3: Ignition;

[0110] 4: Ring component;

[0111] 5: Resin components;

[0112] 6: cover component;

[0113] 10: Accommodation space;

[0114] 20: Gas generating agent (an example of a gas source);

[0115] 100: Gas generator.

Claims

1. A gas generator comprising: a housing defining an igniter mounting hole; and The igniter assembly is mounted on the housing in a manner of blocking the igniter mounting hole, and defines a storage space for storing the gas source together with the housing. The igniter assembly comprises an igniter, a collar member, a resin member and a cover member, wherein: The igniter comprises: an ignition portion, formed with an ignition chamber for accommodating explosive; and a conductive portion, to which an ignition current for igniting the explosive is supplied, the igniter is configured so that the ignition portion is located on the inner side of the accommodating space relative to the conductive portion, and the igniter is configured to operate by the ignition current supplied to the conductive portion, whereby the ignition portion is ruptured to discharge the combustion product of the explosive; The collar member is made of metal, formed into a cylindrical shape, and inserted into the igniter mounting hole in a manner of surrounding the igniter; The resin member is made of resin and is disposed between the igniter and the collar member, and the resin member integrally joins the igniter and the collar member at least in a state where the conductive portion is exposed from the resin member; The cover member is made of metal, is configured to surround the ignition portion and the resin member in a manner that the igniter and the resin member are sealed relative to the storage space, and is cracked when the igniter is operated. The cover member is welded to the collar member over its entire circumference so as to straddle a boundary line between the resin member and the collar member.

2. The gas generator according to claim 1, wherein: A gas generating agent and pressurized gas as the gas source are accommodated in the accommodation space.

3. The gas generator according to claim 1 or 2, wherein: The cover member is formed so as to ensure a space between the cleavage portion, which is a site where the ignition portion cleaves, and the cover member.

4. The gas generator according to claim 3, wherein: The ignition part comprises: a cup body including a cylindrical peripheral wall part and a cover wall part which closes one end of the peripheral wall part and forms the rupture part; and a closing member which is configured to close an opening formed at the other end of the peripheral wall part and defines the ignition chamber together with the cup body. The ignition part is configured such that when the igniter is operated, the cover wall part is ruptured, thereby discharging the combustion product of the detonator to the outside of the ignition chamber. The cover member includes: a cylindrical peripheral wall facing portion disposed to face and contact the peripheral wall portion; and a dome-shaped cover wall facing portion formed to face the cover wall portion and protrude toward the storage space.

5. The gas generator according to claim 3, wherein: The ignition part comprises: a cup body, including a cylindrical peripheral wall part and a cover wall part that closes one end of the peripheral wall part and forms the rupture part; and a closing member configured to close the opening formed at the other end of the peripheral wall part and define the ignition chamber together with the cup body. The ignition part is configured so that when the igniter is working, the cover wall part is ruptured, thereby discharging the combustion product of the detonator. The ignition unit further includes a cylindrical holding bracket, and the holding bracket is arranged in the ignition chamber so as to surround the detonator while facing the peripheral wall portion and in contact with the peripheral wall portion.

6. The gas generator according to claim 3, wherein: The ignition part comprises: a cup body, including a cylindrical peripheral wall part and a cover wall part that closes one end of the peripheral wall part and forms the rupture part; and a closing member configured to close the opening formed at the other end of the peripheral wall part and define the ignition chamber together with the cup body. The ignition part is configured so that when the igniter is working, the cover wall part is ruptured, thereby discharging the combustion product of the detonator. The cover wall portion is fractured so that the combustion product is radiated intensively with respect to the cover member, whereby the cover member is fractured.

7. The gas generator according to claim 3, wherein: The ignition part comprises: a cup body, including a cylindrical peripheral wall part and a cover wall part that closes one end of the peripheral wall part and forms the rupture part; and a closing member configured to close the opening formed at the other end of the peripheral wall part and define the ignition chamber together with the cup body. The ignition part is configured so that when the igniter is working, the cover wall part is ruptured, thereby discharging the combustion product of the detonator. The cover wall portion breaks in such a manner as to come into contact with the cover member, whereby the cover member breaks.

8. The gas generator according to claim 1 or 2, wherein: The collar member is welded to the housing over its entire circumference.

Images