Gas generator

Abstract

To provide a gas generator capable of satisfying desired performance while suppressing an increase in cost.SOLUTION: Gas generator 100 includes a housing 10, a partition member 11, a spacer 16 having a cylindrical portion side 11a accommodated in housing 10 on one side of partition member 11, provided along a circumferential direction of housing 10, open on the other side in an axial direction, and provided to cover a through hole side 16a from one side in the axial direction, and a plurality of gas inlet side walls passing through a sidewall portion of the cylindrical portion side 16a, and a gas generating agent 17 accommodated in housing 10 on one side of partition member 11 and outside the cylindrical portion side 16a. 16b, the gas generator includes an igniter 13 capable of igniting and burning a gas generating agent 17, and a filter 19 stored in a housing 10 on the other side of a partition member 11, and a formation area where a plurality of gas inflow ports 16b are formed is smaller than a non-formation area where the plurality of gas inflow ports 16b are not formed in an axial direction.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a gas generator incorporated in an occupant protection device for protecting an occupant in the event of a vehicle collision, and more particularly to a gas generator incorporated in an airbag device mounted on an automobile or the like. [Background technology]

[0002] Airbag devices, which are passenger protection devices, have become widespread from the viewpoint of protecting passengers in automobiles, etc. Airbag devices are installed to protect passengers from impacts that occur during a vehicle collision, and the airbag instantly inflates and deploys during a vehicle collision, thereby acting as a cushion to support the passenger's body.

[0003] Gas generators have a variety of structures. For example, Patent Document 1 discloses a gas generator that includes a spacer that is provided between a gas generating agent and a through hole through which gas generated by combustion of the gas generating agent passes. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Special Publication No. 2014-508064 Summary of the Invention [Problem to be solved by the invention]

[0005] Incidentally, it is desirable to make it possible to easily control (change) the output of a gas generator by simply replacing some parts, for example, while suppressing increases in costs.

[0006] Therefore, the present invention has been made in consideration of the above circumstances, and aims to provide a gas generator that can easily control output (change output) while suppressing increases in costs, for example, by simply replacing some parts. [Means for solving the problem]

[0007] (1) A gas generator of the present invention comprises a cylindrical housing having a gas outlet, a partition member having through holes opening to one and other axial sides of the housing and dividing the interior of the housing in the axial direction, a cylindrical section accommodated in the housing on one side of the partition member in the axial direction, provided circumferentially around the housing, opening to the other axial side and covering the through hole from one side in the axial direction, and a spacer having a plurality of gas inlet ports penetrating a side wall of the cylindrical section, a gas generating agent accommodated in the housing on one side of the partition member in the axial direction and outside the cylindrical section, and generating gas by combustion, and an igniter capable of igniting and burning the gas generating agent, wherein the side wall section is formed, along the axial direction, with a formed region where the plurality of gas inlet ports are formed, and a non-formed region in the side wall section where the plurality of gas inlet ports are not formed, and the formed region is smaller in the axial direction than the non-formed region.

[0008] (2) In the gas generator of (1) above, the forming region is preferably provided over the entire circumference of the side wall portion in the circumferential direction.

[0009] (3) In the gas generator of (1) or (2) above, the formation region is preferably provided on one side of a center portion of the side wall portion in the axial direction.

[0010] (4) In the gas generator of (1) or (2) above, the formation region is preferably provided across a central portion of the side wall portion in the axial direction.

[0011] (5) In the gas generator of (1) or (2) above, the formation region is preferably provided on the other side of the center of the side wall portion in the axial direction.

[0012] (6) In the gas generator of (1) or (2) above, it is preferable that the spacer further has a flange-shaped portion extending from the other end of the cylindrical portion in the axial direction toward the radially outer side of the housing. [Effects of the Invention]

[0013] According to the present invention, it is possible to provide a gas generator that can easily control (change) the output by simply replacing some of the components, for example, while suppressing an increase in cost. [Brief explanation of the drawings]

[0014] [Figure 1] 1 is a schematic cross-sectional view showing a gas generator according to a first embodiment of the present invention. [Figure 2] FIG. 5 is a schematic cross-sectional view showing a gas generator according to a second embodiment of the present invention. [Figure 3] FIG. 10 is a schematic cross-sectional view showing a gas generator according to a third embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0015] First Embodiment A gas generator 100 according to a first embodiment of the present invention will now be described with reference to FIG.

[0016] FIG. 1 is a schematic cross-sectional view showing a gas generator 100 according to a first embodiment of the present invention.

[0017] As shown in FIG. 1, gas generator 100 is a cylinder-type gas generator having a long, approximately cylindrical outer shape, and includes a housing 10, a partition member 11, a holder 12, an igniter 13, a cup-shaped member 14, a support member 15, a spacer 16, a gas generating agent 17, a sealing tape 18, a filter 19, and a blocking portion 20.

[0018] The housing 10 is cylindrical and has a peripheral wall portion 10a, and accommodates a partition member 11, an igniter 13, a cup-shaped member 14, a support member 15, a spacer 16, a gas generating agent 17, a sealing tape 18, a filter 19, and the like. The interior of the housing 10 is partitioned in the axial direction by the partition member 11, and the igniter 13, the cup-shaped member 14, the support member 15, the spacer 16, the gas generating agent 17, and the sealing tape 18 are accommodated on one side of the partition member 11 in the axial direction (lower in the plane of FIG. 1 ) of the interior of the housing 10, and the filter 19 is accommodated on the other side of the partition member 11 in the axial direction (upper in the plane of FIG. 1 ). By dividing the interior of the housing 10 with the partition member 11 in this way, a combustion chamber in which the gas generating agent 17 is accommodated and a filter chamber in which the filter 19 is accommodated can be formed within the housing 10.

[0019] The peripheral wall portion 10a is a long cylindrical shape with openings at both axial ends. Note that, hereinafter, the axial direction of the peripheral wall portion 10a may be simply referred to as the axial direction. The radial direction of the peripheral wall portion 10a may be simply referred to as the radial direction. The circumferential direction of the peripheral wall portion 10a may be simply referred to as the circumferential direction. The peripheral wall portion 10a has a plurality of gas ejection ports 10c.

[0020] Gas outlets 10c are holes for ejecting gas generated inside gas generator 100 to the outside, and a plurality of gas outlets 10c are provided along the circumferential and axial directions. The plurality of gas outlets 10c ejects gas that has passed through filter 19 to the outside of housing 10. The plurality of gas outlets 10c face filter 19 in the radial direction.

[0021] The closing portion 20 is attached to the other axially open end of the peripheral wall portion 10a and closes the open end. For example, the closing portion 20 is made of a metal such as stainless steel, iron steel, an aluminum alloy, or a stainless alloy.

[0022] The partition member 11 extends in a direction perpendicular to the axial direction and is provided to separate the interior of the housing 10 in the axial direction. The partition member 11 is generally flat. The partition member 11 is fixed to the inner circumferential surface of the peripheral wall portion 10a. For example, the partition member 11 is fixed to the inner circumferential surface of the peripheral wall portion 10a by welding or the like. The partition member 11 is located on one side of the filter 19 in the axial direction and supports the filter 19 from one side in the axial direction. The partition member 11 has a through hole 11a.

[0023] The through hole 11a penetrates the central portion of the partition member 11 in the radial direction in the axial direction, and is open to one side in the axial direction and the other side in the axial direction. The through hole 11a is provided so that gas generated by combustion of the gas generating agent 17 can pass through. In other words, the gas generated by combustion of the gas generating agent 17 passes through the through hole 11a and flows from one side of the partition member 11 to the other side in the axial direction. The opening of the through hole 11a on one side in the axial direction is closed by a sealing tape 18. The opening of the through hole 11a on the other side in the axial direction is located radially inward of the filter 19. The through hole 11a has a circular shape when viewed in the axial direction.

[0024] Holder 12 is attached to one axially open end of peripheral wall portion 10a and closes the open end. Holder 12 holds igniter 13. For example, holder 12 is made of a metal such as stainless steel, iron steel, aluminum alloy, or stainless alloy.

[0025] The igniter 13 is capable of igniting a transfer charge (not shown) in the cup-shaped member 14. Specifically, the igniter 13 is disposed at one end in the axial direction (i.e., the portion closer to the holder 12) as ignition means for igniting and burning the gas generating agent 17 via the ignited transfer charge (not shown). The igniter 13 and the holder 12 to which the igniter 13 is fixed function as ignition means for generating a flame for burning the gas generating agent 17, which will be described later.

[0026] More specifically, igniter 13 comprises a base frame for inserting and holding a pair of terminal pins 13b, and a squib cup 13a attached to the base frame. A resistor (bridge wire) is attached to connect the tips of terminal pins 13b inserted into squib cup 13a, and an ignition charge is filled in squib cup 13a 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. The squib cup 13a may be filled with not only the ignition charge but also a transfer charge, and examples of transfer charges that can be placed together with the ignition charge include a composition made of a metal / oxidizer, such as boron / potassium nitrate, a composition made of titanium hydride / potassium perchlorate, or a composition made of boron / 5-aminotetrazole / potassium nitrate / molybdenum trioxide. For example, the squib cup 13a is generally made of metal or resin.

[0027] When a collision is detected, a predetermined amount of current flows through the resistor via the terminal pin 13b. This current flow through the resistor generates Joule heat, which causes the ignition charge to start burning. The high-temperature flame generated by the combustion ruptures the squib cup 13a containing the ignition charge. If nichrome wire is used for the resistor, the time from when the current flows through the resistor to when the igniter 13 is activated is less than 2 milliseconds.

[0028] The cup-shaped member 14 has a generally cylindrical shape with a bottom and an open end on one axial side, and includes a space (also called a transfer chamber, which is a space surrounded by the inner wall of the cup-shaped member 14, the igniter 13, and the holder 12) for accommodating a transfer charge (not shown). The cup-shaped member 14 is attached to the holder 12 so that the space provided therein faces the igniter 13. The cup-shaped member 14 has no openings in either the side wall or the top wall, and surrounds the space provided therein. When the transfer charge in the transfer chamber is ignited by the activation of the igniter 13, the cup-shaped member 14 bursts, deforms, or melts due to an increase in pressure in the internal space and the conduction of the generated heat.

[0029] Suitable materials for the cup-shaped member 14 include metal members such as stainless steel, steel, aluminum, aluminum alloy, stainless steel, stainless steel alloy, etc., and resin members such as thermosetting resins typified by epoxy resin, polybutylene terephthalate resin, polyethylene terephthalate resin, polyamide resin (e.g., nylon 6, nylon 66, etc.), polypropylene sulfide resin, polypropylene oxide resin, etc. In particular, aluminum alloys or iron-based metal materials such as stainless steel and steel, which have relatively higher mechanical strength than aluminum, are preferred.

[0030] The support member 15 is supported by the cup-shaped member 14 from one side in the axial direction, and supports the gas generating agent 17 from one side in the axial direction. For example, the support member 15 is made of a material having cushioning properties.

[0031] Spacer 16 is a member for forming a space on one side of through hole 11a in the axial direction, which space communicates with through hole 11a and does not contain gas generating agent 17. Spacer 16 is one of a plurality of spacers 16, 116 (see FIG. 2), 216 (see FIG. 3) that can be used in gas generator 100. In the present embodiment, spacer 16 is selected from a plurality of spacers 16, 116, 216, and spacer 16 is used so that gas generator 100 satisfies the desired performance. The material of spacer 16 is not particularly limited. Furthermore, the dimensions of spacer 16 in the axial direction need only be such that it can be accommodated in the combustion chamber. Spacer 16 has a cylindrical portion 16a, a plurality of gas inlet ports 16b, and a flange-shaped portion 16c.

[0032] The cylindrical portion 16a is cylindrical and is accommodated in the housing 10 on one side of the partition member 11 in the axial direction. The cylindrical portion 16a is provided circumferentially and is annular along the circumferential direction, with one end of the cylindrical portion 16a in the axial direction being closed and the other end of the cylindrical portion 16a in the axial direction being open to the other side in the axial direction. The radial dimension (diameter) of the cylindrical portion 16a is larger than the radial dimension (diameter) of the through hole 11a. The cylindrical portion 16a is connected to one axial end face of the partition member 11 and is provided so as to cover the through hole 11a from one axial side.

[0033] Each of the gas inlets 16b penetrates the side wall of the cylindrical portion 16a. The gas inlets 16b are arranged side by side in the axial and circumferential directions. Each of the gas inlets 16b is circular, but may be elliptical, rectangular, or triangular. The total opening area of ​​the gas inlets 16b is larger than the opening area of ​​the through-hole 11a. The opening dimension (diameter) of each of the gas inlets 16b is smaller than the width dimension (diameter) of the gas generating agent 17.

[0034] The gas flow inlet 16b-forming region in the sidewall of the cylindrical portion 16a, where the gas flow inlets 16b are formed, is smaller in the axial direction than the non-gas flow inlet 16b-not-forming region in the sidewall of the cylindrical portion 16a. That is, the axial dimension of the gas flow inlet 16b-forming region (see L1) is smaller than the axial dimension of the non-gas flow inlet 16b-not-forming region (see L2). Here, the gas flow inlet 16b-forming region is the region from the axial end of the gas flow inlet 16b located furthest from the other axial end of the gas flow inlet 16b located furthest from the other axial end of the gas flow inlet 16b. The non-gas flow inlet 16b-not-forming region is the region of the sidewall of the cylindrical portion 16a other than the gas flow inlet 16b-forming region. The gas flow inlet 16b-forming region is provided around the entire circumferential circumference of the sidewall of the cylindrical portion 16a and is located on one side of the center of the sidewall of the cylindrical portion 16a in the axial direction. In this embodiment, the gas flow inlet 16b-forming region is provided from one end of the sidewall of the cylindrical portion 16a to the other end in the axial direction.

[0035] The flange portion 16c extends radially outward from the other axial end of the cylindrical portion 16a. The flange portion 16c is provided in the circumferential direction. The flange portion 16c is connected to one axial end face of the partition member 11. For example, the flange portion 16c is fixed to the inner circumferential surface of the peripheral wall portion 10a by welding or the like.

[0036] The gas generating agent 17 is accommodated in the housing 10 on one side of the partition member 11 in the axial direction and outside the cylindrical portion 16a, and generates gas by combustion. The gas generating agent 17 is an integrally molded product that is ignited by a flame generated by ignition by the igniter 13 and burns to generate gas. The gas generating agent 17 is generally formed as a molded product 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, basic metal carbonates such as basic copper carbonate, perchlorates such as ammonium perchlorate or potassium perchlorate, and nitrates containing cations selected from alkali metals, alkaline earth metals, transition metals, and ammonia. Suitable nitrates include sodium nitrate and potassium nitrate. Suitable additives include binders, slag formers, and combustion control agents. 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 formers include silicon nitride, silica, and acid clay. Suitable combustion control agents include metal oxides, ferrosilicon, activated carbon, and graphite.

[0037] The sealing tape 18 is attached as a sealing member to one axial end face of the partition member 11 so as to close the opening of the through hole 11a on one axial side. The sealing tape 18 is made of metal, for example. Aluminum foil with an adhesive material applied to one side can be suitably used as the sealing tape 18, and the sealing tape 18 ensures the airtightness of the combustion chamber inside the housing 10.

[0038] The filter 19 is accommodated in the housing 10 on the other side of the partition member 11 in the axial direction. The filter 19 is provided circumferentially and is annular along the circumferential direction. The filter 19 is provided so that gas that has passed through the through-hole 11a passes through the filter 19. For example, the gas that has passed through the through-hole 11a enters the filter 19 from the radially inner side, passes through the filter 19, and exits the filter 19 toward the radially outer side. The filter 19 is elongated in the axial direction. One end of the filter 19 in the axial direction is supported in the axial direction by the partition member 11, and the other end of the filter 19 in the axial direction is supported in the axial direction by the blocking portion 20. The filter 19 is supported so as not to move in the radial direction by being sandwiched between the partition member 11 and the blocking portion 20.

[0039] The filter 19 is a cylindrical member with a generally cylindrical hollow center. Using the filter 19 made of the cylindrical member reduces the flow resistance of the working gas during operation, allowing for efficient gas flow. The filter 19 may be made of wire material made of metal, such as stainless steel or steel, or a wound or pressed mesh material. Specifically, a knitted wire mesh, a plain weave wire mesh, or an assembly of crimped metal wires may be used. The filter 19 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 19, and also as a removal means for removing slag and other contaminants contained in the gas. A modified version of the filter 19 may be a filter with a labyrinth-shaped flow path formed by combining generally cylindrical or cone-shaped metal components. This allows the path of the working gas to be diverted in various directions, thereby cooling the gas and removing slag.

[0040] Furthermore, while the filter 19 has been illustrated as being made of a so-called knitted wire mesh, it is also possible to use a filter made by winding punched metal or an 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 knitted wire mesh described above, the same effects as those described in the above-described embodiment of the present invention can be obtained.

[0041] 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.

[0042] Next, the operation of gas generator 100 during activation described above will be described. When a vehicle equipped with an airbag device incorporating gas generator 100 of the present embodiment collides, the collision is detected by collision detection means separately provided in the vehicle, and igniter 13 is activated based on this detection. When igniter 13 is activated, the pressure inside igniter 13 increases due to combustion of the ignition charge, causing the tip of squib cup 13a of igniter 13 to rupture, and flame flows from the tip of squib cup 13a of igniter 13 into a transfer chamber inside cup-shaped member 14. The flame that has flowed into the transfer chamber ignites the transfer charge inside the transfer chamber, and as the pressure in the internal space increases and the generated heat is conducted, cup-shaped member 14 ruptures, deforms, or melts, and then support member 15 also ruptures, deforms, or melts. Thereafter, the flame caused by the ignited transfer charge flows out to the gas generating agent 17 side via the tip of the ruptured, deformed or melted cup-shaped member 14 and the support member 15 .

[0043] The flame flowing in in this manner ignites and burns the gas generating agent 17, generating a large amount of gas. This combustion of the gas generating agent 17 increases the pressure inside the housing 10, and the generated gas flows into the cylindrical portion 16a from the gas inlet 16b, breaks the sealing tape 18, passes through the through-hole 11a, passes through the through-hole 11a, and then passes through the filter 19, and is ejected to the outside of the housing 10 from the gas outlet 10c. The gas ejected from the gas outlet 10c is then guided into the airbag, inflating and deploying the airbag. Note that the gas passes through the spacer 16, the through-hole 11a, and the filter 19 before being ejected from the gas outlet 10c, so that residue contained in the gas can be efficiently removed and the gas can be cooled to a predetermined temperature.

[0044] In gas generator 100, spacer 16 can reduce the amount of gas generating agent 17 flowing into partition member 11 compared to a case in which spacer 16 is not present, preventing gas generating agent 17 from clogging through hole 11a and blocking through hole 11a with gas generating agent 17, and suppressing an increase in the internal pressure of the combustion chamber. Furthermore, since spacer 16 is provided with a non-forming region, the gas flow path can be blocked by the non-forming region. Furthermore, by using spacer 16 in which multiple gas inflow ports 16b are formed at positions such that gas generator 100 satisfies the desired performance, gas generator 100 can be made to satisfy the desired performance without changing the size of gas generator 100, changing the type of gas generating agent 17, adding new parts, or the like. For example, by using spacer 116 or spacer 216, etc. instead of spacer 16, the ignition ability of gas generating agent 17 can be significantly changed, enabling a wide range of Pt performance control. Furthermore, the spacer 16 can collect residue contained in the gas, thereby preventing an increase in the amount of residue ejected from the gas ejection port 10c.

[0045] As described above, gas generator 100 in the first embodiment of the present invention described above comprises cylindrical housing 10 having gas outlet 10c, partition member 11 having through hole 11a opening to one axial side and the other axial side of housing 10 and dividing the interior of housing 10 in the axial direction, spacer 16 having cylindrical portion 16a accommodated in housing 10 on one side of partition member 11 in the axial direction, provided around housing 10 in the circumferential direction, opening to the other axial side and provided so as to cover through hole 11a from one axial side, and a plurality of gas inlet ports 16b penetrating a side wall portion of cylindrical portion 16a, and the gas generator 100 of the present embodiment comprises: gas generating agent 17 accommodated in housing 10 outside portion 16a and combusting to generate gas; igniter 13 capable of igniting and burning gas generating agent 17; and filter 19 accommodated in housing 10 on the other side of partition member 11 in the axial direction, wherein gas that has passed through through hole 11a passes through filter 19 and is ejected from gas outlet 10c to the outside of housing 10, and a formation region in which multiple gas inlet ports 16b are formed in the side wall portion of tubular portion 16a is smaller in the axial direction than a non-formation region in which multiple gas inlet ports 16b are not formed in the side wall portion of tubular portion 16a. Because the formation region and non-formation region are provided in this way, gas generator 100 of the present embodiment has lower Pt performance than the gas generators of the second and third embodiments described below.

[0046] According to this, the formed region is smaller than the non-formed region in the axial direction, so that the formed region can be easily provided at a position where gas generator 100 satisfies the desired performance, and gas generator 100 can be made to satisfy the desired performance (for example, Pt performance) without changing housing 10, etc. In other words, by simply replacing the spacer (replacing some parts), for example, it is possible to provide gas generator 100 whose output can be easily controlled (output changed) while suppressing an increase in costs.

[0047] In gas generator 100 in the first embodiment of the present invention described above, the formation region is provided over the entire circumference of the side wall portion of tubular portion 16a in the circumferential direction.

[0048] According to this, spacer 16 in which the formation region is provided over the entire circumference of the side wall portion of cylindrical portion 16a in the circumferential direction can enable gas generator 100 to satisfy the desired performance while suppressing an increase in costs.

[0049] In gas generator 100 in the first embodiment of the present invention described above, the formation region is provided on one side (igniter 13 side) of the center of the side wall portion of cylindrical portion 16a in the axial direction.

[0050] According to this, by using spacer 16 in which the formation region is provided on one side of the center of the side wall portion of cylindrical portion 16a in the axial direction, it is possible to suppress an increase in costs while allowing gas generator 100 to satisfy the desired performance.

[0051] Furthermore, in the gas generator 100 according to the first embodiment of the present invention described above, the spacer 16 further has a flange-shaped portion 16c extending from the end of the cylindrical portion 16a on the other side (the partition member 11 side) in the axial direction toward the radially outer side of the housing 10.

[0052] This allows the spacer 16 to be fixed more easily by the flange portion 16c.

[0053] Second Embodiment A gas generator 200 according to a second embodiment of the present invention will now be described with reference to Fig. 2. In this embodiment, parts having the same reference numerals as those in the first embodiment down to the last two digits are similar to the parts in the first embodiment, and therefore descriptions thereof may be omitted. In addition, parts in this embodiment that are not particularly described are also similar to those in the first embodiment, and therefore descriptions and illustrations thereof may be omitted.

[0054] FIG. 2 is a schematic cross-sectional view showing a gas generator 200 according to a second embodiment of the present invention. As shown in FIG. 2, gas generator 200 differs from gas generator 100 mainly in that gas generator 200 includes partition member 111 instead of partition member 11, and spacer 116 instead of spacer 16.

[0055] The partition member 111 differs from the partition member 11 mainly in that the partition member 111 has a protrusion 111b.

[0056] The protruding portion 111b protrudes to the other axial side, is positioned radially inside the filter 119, and supports the filter 119 in the radial direction. The protruding portion 111b is fitted into an inner peripheral portion 119a of the filter 119.

[0057] Note that spacer 116 is selected, for example, from a plurality of spacers 16 (see FIG. 1), 116, 216 (see FIG. 3) that can be used in gas generator 200. In the present embodiment, spacer 116 is selected from a plurality of spacers 16, 116, 216, and spacer 116 is used so that gas generator 200 satisfies desired performance. Spacer 116 differs from spacer 16 mainly in that the positions of a plurality of gas inlet ports 116b are different from the positions of a plurality of gas inlet ports 16b.

[0058] The gas flow inlet 116b-forming region in the sidewall of the cylindrical portion 116a, where the gas flow inlets 116b are formed, is smaller in the axial direction than the gas flow inlet 116b-non-forming region in the sidewall of the cylindrical portion 116a where the gas flow inlets 116b are not formed. That is, the axial dimension of the gas flow inlet 116b-forming region (see L11) is smaller than the axial dimension of the non-gas flow inlet 116b-non-forming region (see L12+L13). Here, the gas flow inlet 116b-forming region is the region from the axial end of the gas flow inlet 116b located furthest from the other .... The non-gas flow inlet 116b-non-forming region is the region of the sidewall of the cylindrical portion 116a other than the gas flow inlet 116b-forming region. The gas flow inlet 116b-forming region is provided around the entire circumferential direction of the sidewall of the cylindrical portion 116a and straddles the center of the sidewall of the cylindrical portion 116a in the axial direction. In this way, since a formed region and a non-formed region are provided, the Pt performance of gas generator 200 of the present embodiment is greater than that of the first embodiment and less than that of the gas generator of a third embodiment described later.

[0059] As explained above, in gas generator 200 in the second embodiment of the present invention described above, the formation region is provided across the center of the side wall portion of the cylindrical portion in the axial direction.

[0060] According to this, spacer 116, whose formation region is provided across the center of the side wall portion of cylindrical portion 116a in the axial direction, can enable gas generator 200 to satisfy desired performance (for example, Pt performance) while suppressing increases in costs.

[0061] <Third embodiment> A gas generator 300 according to a third embodiment of the present invention will now be described with reference to Fig. 3. In this embodiment, parts having the same reference numerals as those in the second embodiment down to the last two digits are similar to the parts in the second embodiment, and therefore descriptions thereof may be omitted. Furthermore, parts in this embodiment that are not particularly described are also similar to those in the second embodiment, and therefore descriptions and illustrations thereof may be omitted.

[0062] FIG. 3 is a schematic cross-sectional view showing a gas generator 300 according to a third embodiment of the present invention.

[0063] As shown in FIG. 3, the gas generator 300 differs from the gas generator 200 mainly in that the gas generator 300 includes a spacer 216 instead of the spacer 116 .

[0064] Note that spacer 216 is selected, for example, from a plurality of spacers 16 (see FIG. 1), 116 (see FIG. 2), and 216 that can be used in gas generator 300. In the present embodiment, spacer 216 is selected from a plurality of spacers 16, 116, and 216, and spacer 216 is used so that gas generator 300 satisfies desired performance. Spacer 216 differs from spacer 116 mainly in that the positions of a plurality of gas inlet ports 216b are different from the positions of a plurality of gas inlet ports 116b.

[0065] The gas flow inlet 216b-forming region in the sidewall of the cylindrical portion 216a, where the gas flow inlets 216b are formed, is smaller in the axial direction than the gas flow inlet 216b-non-forming region in the sidewall of the cylindrical portion 216a where the gas flow inlets 216b are not formed. That is, the axial dimension of the gas flow inlet 216b-forming region (see L21) is smaller than the axial dimension of the gas flow inlet 216b-non-forming region (see L22). Here, the gas flow inlet 216b-forming region is the region from the axial end of the gas flow inlet 216b located furthest in the axial direction to the axial end of the gas flow inlet 216b located furthest in the axial direction. The non-gas flow inlet 216b-non-forming region is the region of the sidewall of the cylindrical portion 216a other than the gas flow inlet 216b-forming region. The gas flow inlet 216b-forming region is provided around the entire circumferential direction of the sidewall of the cylindrical portion 216a and is provided on the other side of the center of the sidewall of the cylindrical portion 216a in the axial direction. In the present embodiment, the forming region is provided from the other end of the side wall portion of cylindrical portion 216a in the axial direction toward one side. As a forming region and a non-forming region are provided in this manner, the Pt performance of gas generator 300 of the present embodiment is greater than that of the gas generators of the first and second embodiments.

[0066] As described above, in gas generator 300 in the third embodiment of the present invention described above, the formation region is provided on the other side (partition member 211 side) of the center of the side wall part of tubular part 216a in the axial direction.

[0067] According to this, by using spacer 216 in which the formation region is provided on the other side of the center of the side wall portion of cylindrical portion 216a in the axial direction, it is possible to suppress an increase in costs while allowing gas generator 300 to satisfy the desired performance (e.g., Pt performance).

[0068] <Other embodiments, etc.> Although the embodiments of the present invention have been described above, they are merely illustrative examples and do not limit the present invention, and the specific configurations and the like can be appropriately modified in design. Furthermore, the functions and effects described in the embodiments of the invention are merely a list of the most preferable functions and effects resulting from the present invention, and the functions and effects of the present invention are not limited to those described in the embodiments of the present invention. For example, parts of each embodiment may be appropriately combined as needed.

[0069] In the first to third embodiments described above, the cylindrical portions 16a, 116a, and 216a have a constant diameter, but this is not limiting. For example, the cylindrical portions may be tapered, gradually decreasing or increasing in diameter toward one side or the other in the axial direction.

[0070] Furthermore, the spacers are not limited to those shown in the first to third embodiments described above, and it is sufficient if a forming region and a non-forming region (dimension of the forming region in the axial direction < dimension of the non-forming region in the axial direction) are appropriately provided in accordance with the desired performance (for example, Pt performance) of each gas generator.

[0071] Furthermore, in the gas generators of the above-described embodiments, a filter is provided inside the housing, but the gas generators may not be provided with a filter. [Explanation of symbols]

[0072] 10,110,210 Housing 10a,110a,210a Peripheral wall part 10c, 110c, 210c gas outlet 11,111,211 Partition members 11a,111a,211a through hole 111b,211b Projection 12,112,212 holder 13,113,213 Igniter 13a, 113a, 213a Squib Cup 13b, 113b, 213b terminal pins 14,114,214 Cup-shaped member 15,115,215 Supporting member 16,116,216 spacers 16a, 116a, 216a Cylindrical part 16b, 116b, 216b Gas inlet 16c,116c,216c collar 17,117,217 Gas Generants 18,118,218 Sealing tape 19,119,219 filters 19a,119a,219a Inner circumference 20,120,220 Occlusion 100,200,300 Gas Generator

Claims

1. a cylindrical housing having a gas outlet; a partition member having a through hole opening to one side and the other side of the housing in the axial direction, the partition member dividing the interior of the housing in the axial direction; a spacer including a cylindrical portion accommodated in the housing on one side of the partition member in the axial direction, provided around the housing in a circumferential direction, opening to the other side in the axial direction, and provided to cover the through hole from the one side in the axial direction, and a plurality of gas inlet ports penetrating a side wall portion of the cylindrical portion; a gas generating agent that is accommodated in the housing on one side of the partition member in the axial direction and outside the cylindrical portion, and that generates gas by burning; an igniter capable of igniting and burning the gas generating agent; Equipped with a formation region in which the plurality of gas inlet ports are formed and a non-formation region in which the plurality of gas inlet ports are not formed in the side wall portion are formed along the axial direction, A gas generator, wherein the forming region is smaller than the non-forming region in the axial direction.

2. 2. The gas generator according to claim 1, wherein the forming region is provided over the entire circumference of the side wall portion in the circumferential direction.

3. 3. The gas generator according to claim 1, wherein the forming region is provided on one side of a center portion of the side wall portion in the axial direction.

4. 3. The gas generator according to claim 1, wherein the forming region is provided across a central portion of the side wall portion in the axial direction.

5. 3. The gas generator according to claim 1, wherein the forming region is provided on the other side of a central portion of the side wall portion in the axial direction.

6. 3. The gas generator according to claim 1, wherein the spacer further has a flange-shaped portion extending from the other end of the cylindrical portion in the axial direction toward the outside in the radial direction of the housing.

Images