Gas generator

Abstract

To provide a gas generator that is able to facilitate the design of a device or the like required to be mounted in consideration of an unexpected situation and that is able to cope with the unexpected situation without requiring an extra component.SOLUTION: A gas generator 104 has a long, substantially columnar outer shape and includes: a housing 10; a holder 20 attached to one open end of the housing 10; an igniter 50 held by the holder 20 and configured to ignite a gas generating agent 31; a cup member 32, and a filter 41. A fragile portion 14 that can be cleaved by a pressure of gas generated by combustion of the gas generating agent 31 inside the gas generator 104 in an emergency is formed at a position facing bolts 70, 71 and at a portion facing a portion filled with the gas generating agent 31, in a side surface of the housing 10. The fragile portion 14 is formed linearly along a longitudinal direction of the housing 10.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to a gas generator incorporated in an airbag device as an occupant protection device mounted on an automobile or the like, and more particularly to a so-called cylinder-type gas generator having an elongated cylindrical shape. [Background technology]

[0002] A long cylindrical housing in a cylinder-type gas generator is generally configured such that one end is closed by a closing member and the other end is closed by a holder having an ignition portion (see, for example, Patent Document 1 listed below). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2015-089760 Summary of the Invention [Problem to be solved by the invention]

[0004] However, with respect to the gas generators typified by the above-mentioned patent documents, it is necessary to design the airbag device taking into consideration the direction in which parts (for example, a closing member, a holder, etc.) will fly in the event of a burst due to an unforeseen event (for example, an event that occurs in an emergency such as a vehicle fire), or to take measures such as attaching extra parts to prevent parts from flying off.In other words, there are problems in that the design of the device for attaching the gas generator becomes complicated, or that the extra parts increase the weight and cost.

[0005] Therefore, an object of the present invention is to provide a gas generator that facilitates the design of devices that need to be installed with consideration given to unforeseen circumstances, and that can respond to unforeseen circumstances without requiring any extra parts. [Means for solving the problem]

[0006] (1) A gas generator of the present invention comprises a long cylindrical housing loaded with a gas generating agent that generates gas by combustion and formed with a gas outlet for ejecting the gas, an igniter capable of igniting and burning the gas generating agent, a holder that holds a part of the igniter and is fixed to one axial end of the housing, and a closing member that is fixed to the other axial end of the housing, wherein the gas generator further comprises a bolt that is provided on a side of the housing and is used to attach the gas generator to the inside of a vehicle, and at least a part of the fragile portion is provided in a region from a line that divides the housing in the axial direction perpendicular to the direction in which the bolt extends so as to include the central axis of the housing to the half of the side of the housing opposite to the half on the side on which the bolt extends, and which can be cleaved open by the pressure of gas generated by combustion of the gas generating agent inside the gas generator in an emergency.

[0007] (2) In the gas generator of (1) above, it is preferable that the fragile portion is formed in the housing so that, when the gas generator is attached inside the vehicle via the bolt, the fragile portion ruptures in a direction that coincides with any of the directions away from a seat provided in the vehicle relative to the position where the gas generator is attached.

[0008] (3) In the gas generator of (2) above, when the gas generator is attached to the inside of the seating portion of the seat via the bolt, the fragile portion may be formed in the housing so that when the fragile portion splits, it will split toward the bottom of the vehicle.

[0009] (4) In the gas generator of (2) above, when the gas generator is attached via the bolt to the inside of a backrest of a seat provided in the vehicle, the weak part may be formed in the housing so that when the weak part ruptures, it is positioned so that it ruptures toward the outside of the vehicle.

[0010] (5) In the gas generator of (1) above, the weakened portion is preferably formed linearly along the axial direction of the housing.

[0011] (6) In the gas generator of (1) above, the weakened portion is preferably formed linearly along the circumferential direction of the housing. [Effects of the Invention]

[0012] According to the present invention, it is possible to provide a gas generator that facilitates the design of devices that need to be installed taking into account unforeseen circumstances, and that can respond to unforeseen circumstances without requiring any extra parts. [Brief explanation of the drawings]

[0013] [Figure 1] 2 is a view showing an example of a seat portion to which the gas generator according to the first embodiment of the present invention is attached. FIG. [Figure 2] 1 is a diagram showing the appearance of a gas generator according to a first embodiment of the present invention. [Figure 3] 1 is a schematic diagram (partially omitted) showing the internal structure of a gas generator according to a first embodiment of the present invention, shown partially in cross section. [Figure 4] FIG. 4 is a diagram showing the appearance of a gas generator according to a modified example of the first embodiment of the present invention. [Figure 5] FIG. 5 is a view showing the appearance of a gas generator according to a second embodiment of the present invention. [Figure 6] FIG. 10 is a diagram showing the appearance of a gas generator according to a modified example of the second embodiment of the present invention. [Figure 7] FIG. 10 is a view showing another example of a seat to which a gas generator according to the present invention is attached. DETAILED DESCRIPTION OF THE INVENTION

[0014] First Embodiment A cylinder-type gas generator according to an embodiment of the present invention and a vehicle seat equipped with this gas generator will be described below with reference to Figs.

[0015] (Configuration of seat 100) The seat 100 is an example of a seat for a passenger provided inside a vehicle or the like. The seat 100 includes a seat portion 101 on which the passenger sits, a backrest portion 102 rotatably connected to the seat portion 101, a headrest portion 103 attached to the upper part of the backrest portion 102, and a gas generator 104. Although not shown, a part of the gas generator 104 is attached near a side portion 101a inside the seat portion 101 in a state where it is inserted inside an airbag of an airbag device. Furthermore, although not shown, the airbag device is capable of deploying an airbag from the side portion 101a toward the headrest portion 103.

[0016] (Configuration of gas generator 104) Gas generator 104 has a long, approximately cylindrical outer shape and includes housing 10, a holder 20 attached to one open end of housing 10, and a closing member 12 attached to the other end of housing 10 so as to close the other open end of housing 10.

[0017] The housing 10 is a long, cylindrical member having peripheral walls 10a, 10b, and 10e and openings at both axial ends. A pair of metal bolts 70 and 71 are attached to the side of the housing 10 in the same direction (the X-axis direction in FIG. 2). The bolts 70 and 71 can be attached to and fixed to a fixture (not shown) inside the seat portion 101. In this embodiment, as shown in FIG. 1, the housing 10 is fixed to a fixture (not shown) inside the seat portion 101 via the bolts 70 and 71 so that the longitudinal direction is aligned with the front-to-rear direction of the seat portion 101.

[0018] 2, a weakened portion 14 that can be cleaved open by the pressure of gas generated by the combustion of the gas generating agent 31 inside the gas generator 104 in an emergency is formed on the side of the housing 10 at a position opposite the positions of the bolts 70, 71 and opposite the portion filled with the gas generating agent 31. This weakened portion 14 is formed linearly along the longitudinal direction of the housing 10 (in FIG. 2, the Z-axis direction on the XZ plane). The weakened portion 14 is formed by utilizing a welded portion formed by electric resistance welding in which a steel plate or the like is rolled into a tubular shape and the seam is welded, a portion formed by a groove or a notch, or a portion formed by previously thinning the plate thickness. In other words, the weakened portion 14 is a portion that has lower strength than other portions of the housing 10.

[0019] Closing member 12 is made of a disk-shaped member having a predetermined thickness, and has an annular groove 13 on its peripheral surface for fixation by crimping (an example of a diameter reduction method) described later. This annular groove 13 for fixation by crimping is formed so as to extend circumferentially on the peripheral surface of closing member 12. Also, gas outlets 11 are provided in the peripheral wall near the end of housing 10 on the side where closing member 12 is attached. These gas outlets 11 are holes for ejecting gas generated inside gas generator 104 to the outside, and a plurality of gas outlets 11 are provided along the circumferential and axial directions of housing 10.

[0020] The closing member 12 is made of a metal such as stainless steel, iron steel, aluminum alloy, or stainless alloy. As shown in Fig. 3, with a part of the closing member 12 inserted into one open end of the housing 10, the peripheral wall 10a of the housing 10, which corresponds to a part of the peripheral surface of the closing member 12, is narrowed (crimped) radially inward to form the annular groove 13, thereby crimping and fixing the closing member 12 to the housing 10.

[0021] Holder 20 is made of a metal such as stainless steel, iron steel, aluminum alloy, or stainless alloy, and has a tapered fitting portion 23 into which igniter 50 fits, an annular groove portion 22 for crimping and fixed formed so as to extend circumferentially on the outer circumferential surface, and a fitting portion 21, on the side opposite to the holding position of igniter 50, into which a female connector (not shown) for supplying electricity to igniter 50 can be fitted. Note that holder 20 is crimped and fixed to housing 10 by reducing (crimping) the diameter of peripheral wall 10e of housing 10 in a portion corresponding to annular groove portion 22 provided on the outer circumferential surface of holder 20 inward in the radial direction and engaging with said annular groove portion 22.

[0022] As described above, a female connector is formed in the fitting portion 21 of the holder 20. This female connector is a portion to which a male connector of a harness that transmits a signal from collision detection means that is provided separately from the gas generator 104 is connected. A retainer 60 is attached to the female connector. This retainer 60 is attached to prevent malfunction of the cylindrical gas generator 104 due to electrostatic discharge or the like when the gas generator 104 is transported, and at the stage of assembly into the airbag device, the male connector of the harness is inserted into the female connector, thereby releasing the male connector from contact with the terminal pin 52.

[0023] 3, an igniter 50 is disposed at one axial end of the housing 10 (i.e., the portion closer to the holder 20) as means for igniting the gas generating agent 31. The igniter 50 and the holder 20 that fixes the igniter 50 function as ignition means that generate a flame for burning the granular gas generating agent 31, which will be described later.

[0024] As shown in Fig. 3, igniter 50 is inserted into fitting portion 23 of holder 20 and held together with a substantially cylindrical member 53, which will be described later. More specifically, igniter 50 includes a base frame through which a pair of terminal pins 52 are inserted and which holds the pair, and a squib cup 51 (cup-shaped member) attached to the base frame. A resistor (bridge wire) is attached so as to connect the tips of terminal pins 52 inserted into squib cup 51, and squib cup 51 is filled with an ignition charge so as to surround or be in contact with the resistor. Nichrome wire or the like is generally used as the resistor, and ZPP (zirconium-potassium perchlorate), ZWPP (zirconium-tungsten-potassium perchlorate), lead tricinate, or the like is generally used as the ignition charge. In addition to the ignition charge, a transfer charge may also be filled into squib cup 51. Examples of transfer charges that can be placed together with the ignition charge include a composition consisting of a metal / oxidizer, such as boron / potassium nitrate, a composition consisting of titanium hydride / potassium perchlorate, or a composition consisting of boron / 5-aminotetrazole / potassium nitrate / molybdenum trioxide.

[0025] When a collision is detected, a predetermined amount of current flows through the resistor via terminal pin 52. This current flow through the resistor generates Joule heat, which causes the ignition charge to begin burning. The high-temperature flame generated by the combustion ruptures squib cup 51, which contains the ignition charge. If nichrome wire is used for the resistor, the time from when the current flows through the resistor to when igniter 50 is activated is less than 2 milliseconds.

[0026] Squib cup 51 is generally made of metal or resin. A substantially cylindrical member 53 covers the peripheral wall of squib cup 51 except for the vicinity of the tip, and is fixed together with igniter 50 by crimping to holder 20 with crimping portion 24. Here, substantially cylindrical member 53 is a directional member that directs the direction of the flame generated in igniter 50 upon activation toward cup member 32 (positioning member).

[0027] As shown in FIG. 3, in the internal space of the housing 10, a space 10A in which the gas generating agent 31 and the like are sealed, and a filter 41 are provided in parallel in the axial direction of the housing 10.

[0028] The gas generating agent 31 is a composition that is ignited by a flame generated by ignition by the igniter 50 and burns to generate gas. The gas generating agent 31 is generally formed as a molded body containing a fuel, an oxidizer, and an additive. Examples of fuels that can be used include triazole derivatives, tetrazole derivatives, guanidine derivatives, azodicarbonamide derivatives, hydrazine derivatives, and combinations thereof. Specific examples of suitable fuels include nitroguanidine, guanidine nitrate, cyanoguanidine, and 5-aminotetrazole. Examples of suitable oxidizers include basic metal nitrates such as basic copper nitrate and basic copper carbonate, perchlorates such as ammonium perchlorate and potassium perchlorate, and nitrates containing cations selected from alkali metals, alkaline earth metals, transition metals, and ammonia. Suitable examples of suitable nitrates include sodium nitrate and potassium nitrate. Examples of suitable additives include binders, slag-forming agents, and combustion modifiers. Suitable binders include organic binders such as cellulose derivatives (e.g., hydroxypropylene methyl cellulose), metal salts of carboxymethyl cellulose, and stearates, as well as inorganic binders (e.g., synthetic hydroxytalcite and acid clay). Suitable slag-forming agents include silicon nitride, silica, and acid clay. Suitable combustion-adjusting agents include metal oxides, ferrosilicon, activated carbon, and graphite.

[0029] As shown in Fig. 3, the coil spring 35 is formed by being wound in a spiral shape so that its overall appearance resembles a truncated cone. One end of the coil spring 35 abuts against the squib cup 51, and the other spirally formed end abuts against the gas generating agent 31, thereby applying an elastic force to the gas generating agent 31. Due to this biasing force, the gas generating agent 31 is fixed in the housing 10 by being sandwiched between the coil spring 35 and the cup member 32. Furthermore, the coil spring 35 has an overall truncated cone shape that widens in diameter from the igniter 50 side to the gas generating agent 31 side, which makes it easier to direct the direction of the flame emitted from the igniter 50 toward the gas generating agent 31.

[0030] The cup member 32 (positioning member) is a short, bottomed, cylindrical member that covers one end of the filter 41. It includes a cylindrical portion 32a having an annular groove 32a1 and a bottom portion 32b that closes one end of the cylindrical portion 32a. The cup member 32 is fixed to the inner wall of the housing 10 by a diameter-reducing process (described later) performed from the outside of the housing 10 so that the filter 41 can be positioned at a predetermined position (for example, a position facing the gas outlet 11 as shown in FIG. 3). The cylindrical portion 32a is short enough not to close the gas outlet 11. The bottom portion 32b melts or breaks due to the gas generated during operation. The cup member 32 is made of a resin material or a composite reinforced material containing resin. Examples of the resin material or composite reinforced material containing resin include glass fiber-reinforced PA6 (polyamide 6) and POM (polyacetal, polyoxymethylene). As a modified example, the cup member 32 may be made of a metal such as stainless steel or steel, or an alloy such as an aluminum alloy or stainless alloy.

[0031] As shown in FIG. 3 , after the cup member 32 is installed in the housing 10 with one end of the filter 41 fitted into it, the peripheral wall 10b of the housing 10 is narrowed radially inward (crimped) at a portion corresponding to a part of the circumferential surface of the cylindrical portion 32a of the cup member 32 to form the annular groove 32a1 and the annular groove 41b described below, thereby crimping and fixing the cup member 32 to the housing 10 and the filter 41. This prevents generated gas from bypassing between the inner wall of the housing 10 and the outer periphery of the filter 41 and leaking into the gas outlet 11, while also ensuring sealing. That is, the cup member 32 allows gas generated on the igniter 50 side of the housing 10 to flow into the filter 41 side through a portion of the bottom portion 32b that is split by melting or breaking (a portion corresponding to one end of the hollow portion 41a). The position of the crimping may be any position that corresponds to the circumferential surface of the cylindrical portion 32a of the cup member 32.

[0032] The filter 41 is a cylindrical member having a central hollow portion 41a (e.g., approximately cylindrical or rectangular). As described above, the filter 41 is installed in the housing 10 together with the cup member 32, and then the annular groove 41b is formed by the diameter reduction process. The use of the cylindrical filter 41 reduces the flow resistance of the working gas flowing during operation, enabling efficient gas flow. The filter 41 may be made of wire material made of metal such as stainless steel or steel, or a mesh material wound or compressed by pressing. Specifically, a knitted wire mesh, a plain weave wire mesh, or an assembly of crimped metal wire materials may be used. The filter 41 functions as a cooling means for cooling the gas generated in the housing 10 by removing the high-temperature heat of the gas as it passes through the filter 41, and also functions as a removal means for removing slag and other contaminants contained in the gas. Here, as a modification of the filter 41, a filter having a labyrinth flow path formed by combining roughly cylindrical or cone-shaped metal parts may be used. This allows the path of the working gas to be changed in various directions, thereby enabling cooling of the gas and removal of slag.

[0033] Furthermore, in the above-described embodiment of the present invention, a filter made of so-called knitted wire mesh is used as an example, but it is also possible to use a filter made by winding punched metal or expanded metal instead. Here, punched metal refers to a metal plate in which only openings are provided (i.e., no protrusions are provided around the edges of the openings), and expanded metal refers to a metal plate in which openings are provided in the plate metal member by, for example, making staggered cuts and then expanding the cuts to form a mesh-like structure. Even when such punched metal or expanded metal is used instead of the above-described knitted wire mesh, the same effects as those described in the above-described embodiment of the present invention can be obtained.

[0034] Furthermore, in the above-described perforated metal and expanded metal, the filter is formed as a laminate by winding a single metal plate-like member, but the configuration of the filter is not limited to this. That is, the filter may be formed as a laminate by combining different metal plate-like members each having different layers, or the filter may be formed as a laminate by combining a plurality of layers in which some layers are formed as a single metal plate-like member and the remaining layers are formed as a different single metal plate-like member.

[0035] Next, the operation of gas generator 104 during normal operation as described above will be described. When a vehicle equipped with an airbag device incorporating gas generator 104 of this embodiment collides, the collision is detected by collision detection means separately provided in the vehicle, and igniter 50 is activated based on this detection. When igniter 50 is activated, the pressure inside igniter 50 increases due to combustion of the ignition charge, causing the tip of squib cup 51 of igniter 50 to rupture, and flames flow from the tip of squib cup 51 of igniter 50 to the cup member 32 side inside housing 10.

[0036] The flame flowing in in this manner ignites and burns the gas generating agent 31 in the housing 10, generating a large amount of gas. This combustion of the gas generating agent 31 increases the pressure in the space 10A in the housing 10, and the generated gas melts or breaks open a portion of the bottom surface portion 32b of the cup member 32 corresponding to the hollow portion 41a, and flows into the hollow portion 41a. The generated gas then passes through the filter 41 and is ejected from the gas outlet 11 to the outside of the gas generator 104, but because it passes through the filter 41, the generated gas is cooled to a predetermined temperature. The gas ejected from the gas outlet 11 is then guided into the interior of the airbag to inflate and deploy the airbag.

[0037] Next, an operation of the gas generator 104 described above in an emergency will be described. When a fire or the like occurs in a vehicle equipped with an airbag device incorporating the gas generator 104 of this embodiment and the inside of the gas generator 104 reaches a predetermined high temperature, the gas generating agent 31 burns to generate gas, and the gas pressure inside the housing 10 causes the fragile part 14 to rupture. The gas inside the housing 10 is ejected through the ruptured fragile part 14 in a direction away from the seat 100 provided in the vehicle relative to the position where the gas generator 104 is attached (in this embodiment, the side opposite the occupant).

[0038] (Main features of the gas generator 104) According to this embodiment, it is possible to provide the gas generator 104 that can respond to unexpected situations (for example, events that occur in emergencies such as vehicle fires) without requiring any extra parts. Furthermore, use of the gas generator 104 that can respond to unexpected situations facilitates the design of the airbag device, the seat portion 101, etc.

[0039] <Modification of the first embodiment> Next, a modified example of the first embodiment of the present invention will be described with reference to Fig. 4. In this modified example, parts having the same reference numerals as those in the first embodiment down to the last two digits are the same as those in the first embodiment, and therefore their description may be omitted. Furthermore, parts not specifically described in this modified example are also the same as those in the first embodiment, and therefore their description and illustration may be omitted.

[0040] The gas generator 204 of this embodiment differs from the first embodiment mainly in that the fragile portion 114 is formed in a straight line on a line dividing the housing 110 in the axial direction perpendicular to the extension direction of the bolts 170, 171 (on the YZ plane in Figure 4, in the Z-axis direction) so as to include the central axis of the housing 110, and in that the fragile portion 114 is located in a position facing the bottom side of the vehicle, i.e., in a position where the fragile portion 114 will split open towards the bottom of the vehicle when it splits open.

[0041] Next, an operation of the gas generator 204 described above in an emergency will be described. When a fire or the like occurs in a vehicle equipped with an airbag device incorporating the gas generator 204 of this embodiment and the inside of the gas generator 204 reaches a predetermined high temperature, the gas generating agent burns to generate gas, and the gas pressure inside the housing 110 causes the fragile part 114 to rupture. The gas inside the housing 110 is ejected through the ruptured fragile part 114 in a direction away from the seat relative to the position where the gas generator 204 is attached (towards the bottom of the vehicle in this embodiment).

[0042] According to this modification, it is possible to achieve the same effects as those of the first embodiment.

[0043] Second Embodiment Next, a second embodiment of the present invention will be described with reference to Fig. 5. In this embodiment, parts having the same reference numerals as those in the first embodiment down to the last two digits are the same as those in the first embodiment, and therefore their description may be omitted. Furthermore, parts not particularly described in this embodiment are also the same as those in the first embodiment, and therefore their description and illustration may be omitted.

[0044] The gas generator 304 of this embodiment differs from the first embodiment mainly in that a linear weak portion 214, which is shorter than the weak portion 14 of the first embodiment, is provided at a position opposite to the position where the gas generating agent is filled in the housing 210, and that a weak portion 215 is provided in the housing 210 so as to be perpendicular to the weak portion 214 in the circumferential direction of the housing 210.

[0045] Next, an operation of the gas generator 304 described above in an emergency will be described. When a fire or the like occurs in a vehicle equipped with an airbag device incorporating gas generator 304 of this embodiment and the inside of gas generator 304 reaches a predetermined high temperature, the gas generating agent burns to generate gas, and the gas pressure inside housing 210 causes fragile parts 214, 215 to rupture. The gas inside housing 210 is ejected through fragile parts 214, 215 that have ruptured in a direction away from the seat provided in the vehicle (in this embodiment, the side opposite the occupant) relative to the position where gas generator 304 is attached.

[0046] According to this embodiment, it is possible to achieve the same effects as those of the first embodiment.

[0047] <Modification of the second embodiment> Next, a modified example of the second embodiment of the present invention will be described with reference to Fig. 6. In this modified example, parts having the same reference numerals as those in the first embodiment down to the last two digits are the same as those in the first embodiment, and therefore their description may be omitted. Furthermore, parts not specifically described in this modified example are also the same as those in the first embodiment, and therefore their description and illustration may be omitted.

[0048] Gas generator 404 according to this embodiment differs from the second embodiment mainly in that fragile portions 314, 315 are formed on the opposite side (negative side of the X axis) to the occupant side (positive side of the X axis) of a line dividing housing 310 in an axial direction perpendicular to the extension direction of bolts 370, 371 so as to include the central axis of housing 310 (on the YZ plane in FIG. 6, in the Z axis direction), that is, fragile portions 314, 315 are provided in positions that allow them to be torn open toward the bottom of the vehicle, and that fragile portion 315 is provided on housing 310 so as to be perpendicular to fragile portion 314 in the circumferential direction of housing 310.

[0049] Next, an operation of the gas generator 404 described above in an emergency will be described. When a fire or the like occurs in a vehicle equipped with an airbag device incorporating gas generator 404 of this embodiment and the inside of gas generator 404 reaches a predetermined high temperature, the gas generating agent burns to generate gas, and the gas pressure inside housing 310 causes fragile portion 314 to rupture. The gas inside housing 310 is ejected through fragile portion 314 that has ruptured in a direction away from the seat relative to the position where gas generator 404 is attached (towards the bottom of the vehicle in this embodiment).

[0050] According to this modification, it is possible to achieve the same effects as those of the second embodiment.

[0051] Although the embodiments of the present invention have been described above with reference to the drawings, it should be understood that the specific configurations are not limited to these embodiments. The scope of the present invention is defined by the claims rather than the description of the above embodiments, and further includes all modifications within the meaning and scope of the claims.

[0052] For example, when the housing is divided by a YZ plane including the central axis of the housing, at least a portion of the fragile portion of the housing side surface may be provided in either one of the half on the side where the bolt extends (the half on the side where the bolt is provided relative to the YZ plane) or the opposite half (the half on the side where the bolt is not provided relative to the YZ plane). It is preferable that the fragile portion be present in this region. By providing the fragile portion at a position included in this region, it is possible to prevent the fragile portion from cleaving toward the occupant by attaching the bolt to a device on the occupant's side. Furthermore, the shape of the fragile portion of the present invention is not limited to those of the above-described embodiments and modified examples, and may be any shape, such as a wave shape or a zigzag shape, as long as it is provided in the above-described region.

[0053] Furthermore, for example, by providing the fragile portion of the present invention on the housing so that it ruptures in a direction that coincides with one of the directions away from the seat provided in the vehicle relative to the position where the gas generator is mounted, it is possible to prevent the fragile portion from rupturing toward the occupant.

[0054] Furthermore, as in the modified example shown in FIG. 7 , a gas generator 504 having the same configuration as any one of the above-described gas generators 104, 204, 304, 404 may be provided in the backrest 402 of the seat 400, near a side portion 402a of the backrest 402. Although not shown, in this modified example, the fragile portion is formed in the housing so that when the fragile portion ruptures, it will rupture toward the outside of the vehicle (for example, in the direction from the center of the backrest 402 toward the side portion 402a, and toward the outside where no other seats are provided). In this modified example, parts having the same reference numerals as those in the first embodiment down to the last two digits are the same as those in the first embodiment, and therefore their description may be omitted. In addition, parts not particularly described in this modified example are also the same as those in the first embodiment, and therefore their description and illustration may be omitted.

[0055] This modification also has the same effects as the above-described embodiments and modifications.

[0056] In addition, in the second embodiment, the fragile portion 215 is provided, but it is also possible to provide only the fragile portion 214, or only the fragile portion 215. With these, it is possible to achieve the same effects as in the first embodiment. [Explanation of symbols]

[0057] 10, 110, 210, 310, 410 Housing 10A space 10a, 10b, 10e, 110a, 110b, 110e, 210a, 210b, 210e, 310a, 310b, 310e Peripheral wall 11, 111, 211, 311 Gas outlet 12, 112, 212, 312 Closure member 13, 22, 32a1 Annular groove portion 14, 114, 214, 215, 314, 315 Weak portion 20, 120, 220, 320 holder 21, 23 Fitting part 24 Crimping part 31 Gas Generator 32 Cup member 32a Cylindrical part 32b Bottom part 35 coil spring 41 Filters 41a Hollow part 50 igniter 51 Squib Cup 52 terminal pins 53 Cylindrical member 60 Retainer 70, 71, 170, 171, 270, 271, 370, 371, 470, 471 volts 100, 400 seats 101, 401 seat 101a, 401a, 402a Side 102, 402 Backrest 103, 403 Headrest section 104, 204, 304, 404, 504 Gas Generator

Claims

1. a long cylindrical housing loaded with a gas generating agent that generates gas by burning and having a gas outlet formed therein for ejecting the gas; an igniter capable of igniting and burning the gas generating agent; a holder that holds a portion of the igniter and is fixed to one axial end of the housing; a blocking member fixed to the other axial end of the housing; A gas generator comprising: a bolt provided on a side surface of the housing for mounting the gas generator inside a vehicle; a weak part that can be cleaved open by the pressure of gas generated by combustion of the gas generating agent inside the gas generator in an emergency, is provided in a side surface of the housing in any region from a line that divides the housing axially in a direction perpendicular to the direction in which the bolt extends so as to include the central axis of the housing to a half opposite to the half on the side on which the bolt extends.

2. When the gas generator is attached to the interior of the vehicle via the bolt, 2. The gas generator according to claim 1, wherein the fragile portion is formed in the housing so as to tear in a direction that coincides with any one of directions toward a position where the gas generator is attached, including a direction away from a seat provided in the vehicle.

3. When the gas generator is attached to the inside of the seat portion of the seat via the bolt, 3. The gas generator according to claim 2, wherein the weakened portion is formed in the housing so that when the weakened portion is torn, it will tear toward the bottom of the vehicle.

4. When the gas generator is attached to the inside of the backrest of the seat via the bolt, 3. The gas generator according to claim 2, wherein the weakened portion is formed in the housing so that when the weakened portion tears, it tears in a direction away from the center of the vehicle.

5. 2. The gas generator according to claim 1, wherein the weakened portion is formed linearly along the axial direction of the housing.

6. 2. The gas generator according to claim 1, wherein the weakened portion is formed linearly along the circumferential direction of the housing.

Images