JP2001130368A - Gas generator for air bag - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a gas generator for an air bag prevented from erroneous operation. SOLUTION: In this gas generator for an air bag, two or more ignition means setting fire by impact and two or more gas generating means respectively catching fire to be burnt by means of the ignition means and generating combustion gas for expanding an air bag are housed, and a plurality of gas discharge ports formed in a housing constituting a shell container are closed by means of an interrupting means maintaining an internal pressure of the housing to a fixed pressure. In the gas generator, a first combustion chamber starting to burn firstly and a second combustion chamber starting to burn afterward are separated from each other by means of a wall having a communication hole provided with a fire spread preventing means, so that no fire is started in the second combustion chamber even if fire is set in the first combustion chamber.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an airbag gas generator and an airbag device, comprising two or more ignition means and two or more gas generation means, and controlling the behavior of gas discharge or flow. Adjust.

[0002]

2. Description of the Related Art An airbag system mounted on various kinds of vehicles such as automobiles is used when a vehicle collides at a high speed.
The purpose is to support an occupant with an airbag (bag body) that is rapidly inflated by gas, and to prevent the occupant from being injured by crushing a hard part inside the vehicle such as a steering wheel or a front glass due to inertia. . Such an airbag system generally includes a gas generator that is activated by a collision of a vehicle to release gas, and an airbag that expands by introducing the gas.

[0003] Such an airbag system can be used even if the occupant's physique (for example, a person with a high or low sitting height, an adult or a child, etc.), or his / her riding posture (for example, a posture holding on to a steering wheel) is different. It is desirable that the occupant can be restrained safely. Therefore, conventionally, an airbag system has been proposed which operates in the early stage of operation with as little impact as possible on the occupant. Such gas generators are disclosed in JP-A-8-207696, U.S. Pat.No. 4,998,751 and U.S. Pat.
And in Japanese Patent Application Laid-Open No. 8-207696,
Ignite two types of gas generating agent capsules with one igniter,
A gas generator that generates gas in two stages is disclosed in U.S. Pat.
No. 998,751 and U.S. Pat.No. 4,950,458 each propose a gas generator that provides two combustion chambers for regulating the operation function of the gas generator and generates gas in two stages by the spread of the gas generating agent. .

[0004] However, such a gas generator has a complicated internal structure and a large container.
There is a disadvantage that it causes a high cost. In addition, since the ratio of the surface area of the gas generating agent burning in each stage to the area of the nozzle controlling the combustion is not all preferable, the internal pressure of the housing is too low in the first stage combustion, If the combustion is too high, proper control cannot be performed.

Further, Japanese Patent Application Laid-Open No. Hei 9-183359 and German Patent No. 19
In the 620758, two combustion chambers containing a gas generating agent are provided in a housing, an igniter is arranged for each combustion chamber, and the operation timing of each igniter is adjusted. There is disclosed a gas generator capable of adjusting the operation output of a gas generator. However, in any of the gas generators, the igniters arranged for each combustion chamber are separately arranged, so that assembling (manufacturing) thereof becomes difficult, and the structure itself of the gas generator is complicated. Thus, the volume is large.

[0006]

SUMMARY OF THE INVENTION Accordingly, the present invention is to reduce the overall size of a container, to provide a simple structure, to be easy to manufacture and to be lightweight, and to provide an occupant in an early stage of its operation. Operates with as little impact as possible on
And the physique of the occupant (for example, a person with a high or low sitting height,
Or an adult or child) or its riding position (for example, the position of clinging to the steering wheel) is different, so that the operation output and the output of the gas generator can be arbitrarily increased so that the occupant can be safely restrained. Timing is adjustable,
A gas generator having stable combustion performance is provided.

[0007]

The gas generator for an air bag according to the present invention is a gas generator provided with two or more ignition means in a housing, wherein a gas outlet formed in the housing and a gas outlet formed in the housing are provided. It is characterized by a combination of blocking means such as a seal tape for closing off. In the case where a plurality of combustion chambers are provided in the housing, the gas generating means accommodated in each combustion chamber is ignited and burned simultaneously or with a time lag by different ignition means. By controlling the opening diameter (opening area) and / or the thickness of the sealing tape that closes the gas discharge port, the pressure in the housing when the gas generating means burns (hereinafter referred to as “combustion internal pressure”) is equalized. It is possible to stabilize combustion performance.

That is, the present invention accommodates two or more ignition means which are ignited by an impact, and two or more gas generation means which respectively ignite and burn by the ignition means and generate combustion gas for inflating an airbag. In a gas generator for an air bag, a plurality of gas outlets are formed in a housing forming an outer shell container, and the gas outlets are closed by a shut-off means for maintaining an internal pressure of the housing to a predetermined pressure.
An airbag gas generator characterized in that a burst pressure for bursting the blocking means is adjusted in a plurality of stages by at least one kind of the gas discharge ports and / or at least two kinds of the blocking means.

Preferably, the difference in the maximum internal pressure of the housing when each ignition means is activated is suppressed.

[0010] The burst pressure can be adjusted by any one of or a combination of the diameter and area of the gas outlet and the thickness of the shut-off means. That is, the size of the opening diameter is 1 to 8 m
m or between 1.2 and 4 mm. For the gas outlets with adjacent burst pressures for bursting the shut-off means, the ratio of the different burst pressures is 1.1 / 1 or more, more preferably 4/1.
/1-1.1/1.

The opening area and the opening area ratio are changed in accordance with the dose or surface area of the gas generating agent. The thickness of the blocking means is changed according to the opening area ratio or the amount or surface area of the gas generating agent.

The amount and shape of the gas generating agent can be arbitrarily set in each of the plurality of combustion chambers. The amount of gas generated greatly changes depending on the number of ignitions and the ignition timing. Therefore, compared to a single ignition means, there are a plurality of gas generation behaviors, that is, a plurality of output characteristics,
You can choose one of them. The internal combustion pressure depends on the ratio between the surface area of the gas generating agent and the opening area of the gas outlet. In the case of a plurality of gas generating agents, the surface area of the gas generating agent, that is, the combustion surface area changes depending on the number of ignitions and the ignition timing.

The burst pressure is adjusted by controlling the opening diameter and / or the opening area of the gas outlet to two or more types. Thus, of two or more types of gas outlets formed in the housing, the ratio of the large-diameter gas outlet / small-diameter gas outlet is 4/1 for two types of openings whose sizes are adjacent to each other. 1.11.1 / 1, and the opening area ratio is preferably 97/3３3/97.

The burst pressure is adjusted by controlling the thickness of the blocking means to two or more types. It is preferable that the two or more types of blocking means have a ratio of adjacent thicknesses of 1.1 / 1 to 12/1. The area ratio of two or more types of outlets whose burst pressure was adjusted by two or more types of shutoff means having different thicknesses was 97/3 to 3
/ 97. Further, in the present invention, it can also be performed by controlling the opening diameter and / or opening area of the gas discharge port to two or more types and controlling the thickness of the blocking means to two or more types. Also in this case, the area ratio of the two or more types of discharge ports, whose bursting pressure was adjusted by two or more types of blocking means having different thicknesses, was 97/3 or more.
3/97.

The blocking means comprises a sealing layer having a thickness of 20 μm to 200 μm and an adhesive layer having a thickness of 5 to 100 μm;
Alternatively, a seal tape including an adhesive layer is preferable. In the present invention, the thickness of the seal tape means the thickness of the seal tape and the adhesive layer or the adhesive layer. The blocking means such as a sealing tape has a burst pressure adjusted by the size and / or the thickness of the gas discharge port, and the maximum internal pressure in the housing when the gas generating means burns (hereinafter referred to as “ It does not adjust the combustion performance of the gas generating means or the "combustion maximum internal pressure"). That is, in the gas generator of the present invention, the adjustment of the maximum internal combustion pressure during the combustion of the gas generating means is adjusted by the opening area of the gas discharge port. As a result, even after the seal tape has ruptured, the internal pressure of the housing can be adjusted by the relationship between the opening area and the combustion performance of the gas generating means. It is desirable that the blocking means (especially in the case of a seal tape) also have a moisture-proof function for preventing moisture from entering the housing, but in the present invention, like the gas generating means, In the case where moisture-proof means is separately provided for components which need to be moisture-proof, it is sufficient for the shut-off means to have its burst pressure adjusted in a plurality of stages. As such separate moisture-proof means, for example, in the case of a gas generating means, there is a means of wrapping it with a moisture-proof sheet.

In the gas generator according to the present invention, a plurality of combustion chambers are provided in a housing, gas generating means for generating combustion gas are housed in separate combustion chambers, and gas generation means in each combustion chamber is further provided. The means can be ignited independently by each ignition means so that they are not transmitted by the combustion of other gas generating means. The gas generating means contained in each combustion chamber is desirably a solid gas generating agent having a different surface area per unit weight. For example,
When two combustion chambers for accommodating the gas generating means are provided in the housing, each combustion chamber is provided concentrically adjacent to the radial direction of the housing, or the axial length of the housing is longer than the outermost diameter. As a long cylindrical shape, each combustion chamber can be provided coaxially adjacent and axially and / or radially to the housing. In this case, a communication hole that allows the combustion chambers to communicate with each other may be provided. In the combustion chamber provided in this way, the gas generating means accommodated in each combustion chamber can be separately burned. In that the combustion chamber is a chamber exclusively for containing gas generating means, even if the ignition means is configured to include a transfer charge,
It can be distinguished from the space in which the transfer charge is stored.

The dual pyro inflator having a plurality of openings according to the present invention and having equalized internal combustion pressure (stable combustion performance) has two or more ignition means and a housing for accommodating a gas generating agent. The housing is provided with two or more types of nozzles having different opening diameters / opening areas, and / or the thickness of the blocking means for closing the gas outlet is controlled to two or more types. For example, a large nozzle and a small nozzle are open, and the large nozzle is broken at the first stage of operation of the dual pyro inflator, that is, when the gas generating agent in the first chamber is ignited, and the smaller nozzle is at the later stage, that is, the second nozzle. The feature is that the gas generating agent in the chamber is ignited, or the two igniters are simultaneously ignited and the gas generating agent in both chambers is burned and opened later or at the same time as the large nozzle. In the present invention, in particular, the difference in the propellant filling amount (first
Room and the second room). For example, a large nozzle is opened at an internal pressure of 100 kg / cm ² , and a small nozzle is opened at an internal pressure of 150 kg / cm ² or more. In order to achieve this, it is possible to change the nozzle diameter of the gas discharge port with a constant thickness of the sealing tape, or to change the thickness of the sealing tape with a constant diameter of the nozzle. By adjusting the opening area of the gas outlet and / or the burst pressure of the shutoff means in this way, for example, two combustion chambers are provided in the housing, and the first gas generation means and the second gas generation means are respectively provided. When housed separately in the combustion chamber, ideal combustion conditions (for example, internal combustion pressure, etc.) are always used for combustion by any gas generating means.
Can be burned. In other words, when all the gas outlets are opened from the beginning, it is possible to realize an appropriate combustion environment when the first and second gas generating means burn simultaneously, but the second gas generating means takes about 30 milliseconds. In the case of delayed combustion, the combustion gas of the first gas generating means is released during that time, so that the internal combustion pressure when the second gas generating means burns is slightly higher than when two of them burn simultaneously. Therefore, the combustion environment is not optimal for burning the second gas generating means. If the opening area of the gas outlet is adjusted to be small to compensate for this, if the second gas generating means is burned with a delay of 10 milliseconds or 20 milliseconds, or if it is burned at the same time, The pressure will be high. Therefore, it is difficult to cover all the combustion modes if one type of gas discharge port is simultaneously opened from the beginning. As a result, the internal combustion pressure when the first gas generating agent burns is low, and a large difference is generated between the internal combustion pressure when the second gas generating agent burns. Therefore, in such a gas generator, a plurality of gas exhaust ports are provided, such as a gas outlet opening when the first gas generating means burns and a gas outlet opening when the second gas generating means burns. By opening the outlet at different timings according to the combustion of each gas generating means, each gas generating means can always be burned under ideal combustion conditions (combustion internal pressure).

In order to more characteristically adjust the operating performance of the gas generator, in particular, the change over time of the gas emission amount, the combustion speed, the composition, and the composition ratio in each of the two or more combustion chambers. Alternatively, at least one or more gas generating means having different amounts can be accommodated, and they can be independently ignited and burned at an arbitrary timing. Further, each combustion chamber may be filled with gas generating means having a different amount of gas generated per unit time.

As the gas generating means, in addition to an azide-based gas generator based on an inorganic azide, for example, sodium azide (sodium azide), which has been widely used, a non-azide-based gas generator not based on an inorganic azide is used. can do. However, in consideration of safety, a non-azide-based gas generating agent is desirable. As such a non-azide-based gas generating composition, for example, a nitrogen-containing organic compound such as tetrazole, triazole, or a metal salt thereof and an alkali metal Those containing an oxygen-containing oxidizing agent such as nitrate as a main component, triaminoguanidine nitrate, carbohydrazide, nitroguanidine, etc. as a fuel and a nitrogen source, and an alkali metal or alkaline earth metal nitrate, chlorate as an oxidizing agent, Various compositions such as a composition using perchlorate can be used. In addition, the gas generating means is appropriately selected according to requirements such as a burning rate, non-toxicity, a burning temperature, and a decomposition starting temperature. When using gas generating means having different combustion rates for each combustion chamber, for example, the composition and composition ratio itself, such as using an inorganic azide such as sodium azide or a non-azide such as nitroguanidine as a fuel and a nitrogen source, etc. In addition to using different gas generating means, changing the shape of the composition such as a pellet, a wafer, a hollow column, a disk, a single-hole or a porous body, or depending on the size of the molded body, etc. Gas generating means having a different surface area can be used. In particular, when the shape of the gas generating means is formed in a porous body having a plurality of through-holes, the arrangement of the holes is not particularly limited. An arrangement structure in which the distance between the portion and the center of the hole and the distance between the centers of the holes are substantially equal is desirable. Specifically, for example, in the case of a cylindrical molded body having a circular cross-section, one having a center at the center and six having a hole center at the apex of an equilateral triangle equidistant from each other. Is preferred. One more in the center and 18 around
An arrangement with individual holes is also conceivable. The number and arrangement of these holes are determined by the ease of manufacturing the gas generating agent and the balance between manufacturing cost and performance, and are not particularly limited.

Further, the housing may contain a cooling means for cooling the combustion gas generated by the combustion of the gas generating means. This coolant means is provided in the housing for the purpose of cooling and / or purifying the combustion gas generated by the combustion of the gas generating means. For example, a filter for purifying a conventionally used combustion gas is used. In addition to using a coolant for cooling the generated combustion gas, a laminated wire mesh filter formed by compressing and forming a wire mesh made of an appropriate material into an annular laminate can also be used. This laminated wire mesh coolant is desirably formed by forming a flat knitted stainless steel wire mesh into a cylindrical body, and repeatedly bending one end of the cylindrical body outward to form an annular laminated body. A compression-molded or flat-knit stainless steel wire mesh is formed in a cylindrical body, and this cylindrical body is pressed in the radial direction to form a plate body, and the plate body is wound into a cylindrical shape in multiple layers to form a laminate. And compression molding in a mold or the like. Further, the inside and the outside may have a double-layered structure with different laminated metal nets, and may have a function of protecting the coolant means on the inside and a function of suppressing the expansion of the coolant means on the outside. By supporting the outer periphery of the coolant means with an outer layer made of a laminated metal mesh, a porous cylinder, an annular belt, or the like, the swelling can be suppressed.

Further, the combustion gas generated by the combustion of the gas generating means housed in the two or more combustion chambers reaches the gas outlet through different flow paths for each combustion chamber, and is housed in one combustion chamber. When the gas generating means is a gas generator that is not directly ignited by the combustion gas generated in another combustion chamber, the gas generating means in each combustion chamber is completely provided for each combustion chamber. Since the combustion is performed independently, the ignition and combustion of the gas generating means housed in each combustion chamber can be performed more reliably and independently. As a result, even when the operation timings of the two or more ignition means are considerably shifted, the flame of the gas generation means in one combustion chamber ignited by the ignition means which has been activated first will cause the gas in the other combustion chamber to emit gas. A stable operation output can be obtained without burning the generating means. Such a gas generator can be performed, for example, by arranging a flow path forming member in a housing to form a flow path, and guiding the combustion gas generated in one combustion chamber to the coolant means as it is.

The housing may be formed by casting, forging, pressing or the like a diffuser shell having a gas outlet and a closure shell forming an accommodation space together with the diffuser shell, and joining the two shells. it can. The two shells can be joined by various welding methods, for example, electron beam welding, laser welding, TIG welding, prosection welding and the like. When the diffuser shell and the closure shell are formed by pressing various steel plates such as a stainless steel copper plate, both shells can be easily manufactured and the manufacturing cost can be reduced. Further, by forming both shells into a simple and simple cylindrical shape, the press working becomes easy. As for the material of the diffuser shell and the closure shell, a stainless steel plate is preferable, but a nickel-plated steel plate may be used.

The housing also houses two or more ignition means that operate upon sensing an impact to ignite and burn the gas generating means. As the ignition means, the gas generator of the present invention uses an electric ignition type ignition means which is operated by an electric signal (or an operation signal) transmitted from an impact sensor or the like which senses an impact. The electric ignition type ignition means is configured to include an igniter that operates based on an electric signal transmitted from an electric sensor that senses an impact exclusively by an electric mechanism such as a semiconductor type acceleration sensor. And a transfer charge that is ignited and burned by the operation of the vessel. This transfer charge is distinguished from the gas generation means in that the combustion gas burns the gas generation means and is not for directly inflating the airbag. When two or more igniters each include an igniter, in order to facilitate the mounting of the igniters, the igniters are connected to one initiator collar in the axial direction. It is desirable to provide them in alignment. When the ignition means further includes a transfer charge that is ignited and burned by the operation of the igniter, the transfer charge is divided for each of the igniters, and ignites and burns independently for each of the igniters. It is desirable to form the flame in which the transfer charge corresponding to any one of the igniters does not directly ignite the transfer charge corresponding to the other igniter. As such a structure, for example, each igniter is arranged in an independent igniter accommodating chamber, and a transfer charge is arranged in the igniter accommodating chamber, or in each of the separately independent combustion chambers, It can be placed at a place where it can be ignited and burned by the operation of the vessel. When the transfer charges are divided for each igniter, the gas generating means accommodated in two or more combustion chambers can be ignited and burned by the flames in which the transfer charges of different divisions are burned. The gas generating means in each combustion chamber is opened by opening any one of the plurality of gas outlets in response to the combustion of the gas generating means accommodated in each combustion chamber. Can be burned at a typical combustion internal pressure.

[0024] The two or more ignition means arranged in the housing each include an igniter operated by an electric signal, and the igniters are provided on one initiator collar so as to be axially aligned. Each igniter can be arranged eccentrically with respect to the central axis of the housing.
It is preferable that lead wires for transmitting electric signals connected to the respective igniters are drawn on the same plane and in the same direction, and the lead wires are respectively connected via connectors, and the connectors are connected on the same plane. It is desirable to arrange them in parallel on top. In this connector, it is preferable that each lead wire is drawn in a direction orthogonal to the axial direction of the housing and in the same direction.Moreover, the connector has a different shape for each igniter to be connected, or has irregularities. It is desirable to have positioning means that allows connection to only one of the igniters.

The present invention accommodates two or more ignition means which are ignited by an impact, and two or more gas generation means which respectively ignite and burn by the ignition means and generate combustion gas for inflating the airbag. A plurality of gas outlets are formed in a housing forming a shell container, and the gas outlets are first burned in an airbag gas generator which is closed by a shutoff means for maintaining the internal pressure of the housing to a constant pressure. The first combustion chamber to be started and the second combustion chamber to be started to burn later are separated by a wall having a communication hole.The communication hole is provided with a fire prevention means, and the first combustion chamber has It also includes a gas generator for an air bag, wherein combustion does not cause combustion in the second combustion chamber.

The fire prevention means is, for example, a shielding member, for example, a sealing tape, a shielding plate or the like. The shielding member may shield the communication hole from the first combustion chamber side.

Further, the present invention contains two or more ignition means ignited by an impact, and two or more gas generation means for igniting and burning by the ignition means and generating combustion gas for inflating the airbag, respectively. A plurality of gas outlets are formed in a housing forming an outer shell container, and the gas outlets are first burned in an airbag gas generator which is closed by a shut-off means for maintaining the internal pressure of the housing to a constant pressure. The first combustion chamber which starts to burn is separated by a wall from the second combustion chamber which starts to burn later, and the gas generated in each reaches a gas outlet through a different flow path, characterized in that the gas for an airbag is characterized in that Includes generator.

Different channels may be formed by the channel forming member.

The above-described gas generator for an air bag is housed in a module case together with an air bag (bag) that introduces gas generated by the gas generator and inflates to form an air bag device. In this airbag device, the gas generator operates in conjunction with the detection of the impact by the impact sensor, and discharges the combustion gas from the gas outlet of the housing. This combustion gas flows into the airbag, which breaks the module cover and bulges, forming a shock absorbing cushion between the rigid structure in the vehicle and the occupant.

[0030]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a gas generator for an air bag according to the present invention will be described based on an embodiment shown in the drawings. Embodiment 1 FIG. 1 is a longitudinal sectional view of a gas generator for an air bag according to a first embodiment of the present invention, and has a structure particularly suitable for being arranged on a driver's seat side.

This gas generator comprises a substantially cylindrical inner cylinder member in a housing 3 in which a diffuser shell 1 having a gas discharge port and a closure shell 2 forming an internal storage space together with the diffuser shell are joined. 4 is disposed, and the outside thereof is used as a first combustion chamber. In addition, a stepped portion is provided inside the inner cylinder member, and a substantially flat circular partition is disposed in the stepped portion, and the interior of the inner cylinder is further defined by the partition into two chambers, and a diffuser shell is formed. A second combustion chamber on the side,
An ignition means accommodating chamber 8 is formed on the closure shell side. As a result, in this gas generator, the first combustion chamber 5a and the second combustion chamber 5b are provided concentrically within the housing 3 and are adjacent to the housing in the radial direction. In the first and second combustion chambers, a gas generating agent (9) which burns by an ignition means operated upon receiving an impact to generate combustion gas
a, 9b) are accommodated, and an ignition means which is activated by an impact is accommodated in the ignition means accommodation chamber 8. First combustion chamber
A through hole is formed in the inner cylinder member 4 that defines the 5a and the second combustion chamber 5b.
The through hole is closed by a seal tape 11. However, since the seal tape 11 bursts when the gas generating agent burns, the two combustion chambers can communicate with each other through the through holes 10. The material and thickness of the sealing tape 11 need to be adjusted so that the gas generating agent 9b in the second combustion chamber 5b is broken only when burned. In this embodiment, a 40 μm-thick stainless steel sealing tape is used. In addition, the through hole 10 is
It has a larger opening area than b, and has no function of controlling the internal pressure in the combustion chamber 5b.

The ignition means includes two electric ignition type igniters (12a, 12b) which are activated by an activation signal outputted based on the fact that the sensor detects an impact,
The igniters are provided on one initiator collar 13 in parallel with each other with their heads protruding. In this manner, two igniters (12a, 12a
By providing b), the two igniters are fixed to the initiator collar 13 to be a single member, and can be easily assembled to the gas generator. In particular, in the gas generator shown in this figure, the initiator collar 13 having two igniters (12a, 12b) is formed by making the initiator collar 13 large enough to be inserted into the inner cylinder member 4. After being inserted into the inner cylinder 4, the lower end of the inner cylinder member 4 is swaged to fix the initiator collar, so that the igniter can be easily and surely fixed. Further, when the two igniters (12a, 12b) are arranged on the initiator collar 13, the directions of the respective igniters can be easily regulated.

In this embodiment, the initiator color
One of the igniters 12b is provided in the space between the
(Hereinafter, referred to as a “second igniter”), a substantially cylindrical separation tube 14 is disposed, and a first transfer agent storage chamber 15a is provided outside the separation tube 14 and a second transfer agent storage room is provided inside. Room 15b is defined,
In each of the accommodation chambers, an igniter and a transfer charge that constitutes ignition means together with the igniter are accommodated. As a result, the transfer charge (16a, 16b) constituting the ignition means together with the igniter is surely divided for each igniter (12a, 12b). This first explosive charge storage chamber 15a holds the explosive charge 1 contained therein.
When 6a burns, the seal tape 18 that closes the heat transfer hole 17 formed in the inner cylinder member 4 bursts and communicates with the first combustion chamber 5a. In addition, the second charge storage chamber 15b also has the charge 1 therein.
When 6b burns, the seal tape 20 that closes the heat transfer hole 19 formed in the partition 7 ruptures and communicates with the second combustion chamber 5b.
Therefore, when the gas generator is activated, the flame when the first igniter 12a is ignited (activated) is supplied to the storage chamber 15a.
Ignites and burns the explosive charge 16a therein, and the flame passes through the heat transfer hole 17 formed in the inner cylinder member 4 and is accommodated in the first combustion chamber 5a located in the radial direction of the accommodation chamber 15a. The gas generating agent 9a having seven holes is ignited and burned. Also the second igniter 12b
Ignites and burns the second transfer charge 16b in the storage chamber 15b, and the flame passes through the transfer hole 19 provided in the axial direction of the storage chamber 15b, and the second combustion on the extension thereof The single-hole gas generating agent 9b housed in the chamber 5b is ignited and burned. The combustion gas generated in the second combustion chamber 9b flows into the first combustion chamber 5a through the through hole 10 provided on the diffuser shell 1 side of the inner cylinder member 4. In particular, in the gas generator shown in FIG. 1, the separation cylinder 14 disposed between the initiator collar and the partition has a hole 21 corresponding to the outer shape of the separation cylinder 14 on the lower surface of the partition 7 and the upper surface of the initiator collar 13. Are provided, and the upper end or the lower end of the separation tube 14 is fitted into each hole. By arranging the separation tube 14 in this manner, the flame of the transfer charge generated in any one transfer charge combustion chamber does not directly burn the transfer charge in the other transfer charge accommodating chamber. The gas generating agents accommodated in the combustion chamber are ignited and burned by the flames in which the different types of transfer charges burn. That is, when a transfer charge is burned in the separation tube 14 (that is, in the second transfer charge accommodating chamber), the pressure of the gas generated by the combustion usually causes the separation tube to spread in the radial direction. However, by arranging the separation tube, the upper and lower ends of the separation tube are surely supported by the peripheral walls of the holes into which the separation tubes are fitted, and the separation tube is simply moved between the partition wall and the initiator collar. Leakage of the combustion gas / flame of the transfer charge can be more reliably prevented as compared with the case where it is sandwiched between them.

In the housing 3, a gas generating agent (9a,
A coolant filter 22 for purifying and cooling the combustion gas generated by the combustion of 9b) is provided. It is covered with a short path preventing member 23 so that the combustion gas does not pass between the inner surface 28. The coolant / filter 22
An outer layer 24 for suppressing swelling of the filter 22 due to passage of a combustion gas or the like is disposed outside the filter. This outer layer
24, for example, besides being formed using a laminated metal net, may be formed using a porous cylindrical member having a plurality of through holes in the peripheral wall surface, or a belt-shaped restraining layer in which a band member having a predetermined width is formed into an annular shape. it can. Further, a gap 25 is formed outside the outer layer 24 so that the combustion gas can pass through the entire surface of the filter 22.

The gas generator according to the present invention is characterized by the structure of the gas outlet formed in the diffuser shell 1 and / or the seal tape for closing the gas outlet. The peripheral wall of the diffuser shell 1 of the gas generator shown in FIG. 1 is provided with two types of gas outlets 26a and 26b having different diameters, and the number of each outlet can be the same. In this case, the diameter of the gas outlet 26a is larger than the diameter of the gas outlet 26b, and the number of holes is the same, so that the total opening area of the gas outlet 26a is larger than that of the gas outlet 26b. In this embodiment, the gas outlet 26a has a diameter of 3.0 mm and 10 holes, and the gas outlet 26b has a diameter of 2 mm and 10 holes.
In order to protect the gas generating agent from the influence of the environment such as humidity outside the housing, a seal tape 27 is attached to the outlets 26a and 26b from the inner peripheral surface of the peripheral wall of the diffuser shell 1. This seal tape 27 has a width that allows more room even if the two types of gas outlets arranged in the axial direction of the gas generator are closed at the same time, and from the upper end or the lower end of each outlet 26a, 26b,
It is desirable that there is a margin of 2 to 3 mm to the upper end or the lower end of the seal tape, from an aluminum seal layer having a thickness of 20 μm to 200 μm and an adhesive layer or an adhesive layer having a thickness of 5 to 100 μm. Although it is preferable to use a sealing tape, the type and structure of the sealing tape are not particularly limited as long as a desired effect is exhibited. In this embodiment, a seal tape having an aluminum seal layer having a thickness of 50 μm and an adhesive layer or an adhesive layer having a thickness of 50 μm is used. In this embodiment, the outlets 26a and 26b are arranged in the axial direction of the gas generator housing. However, in order to obtain the effect of the present invention, for example, each outlet is provided with a circumferential wall on the diffuser shell peripheral wall. They may be arranged alternately in a shape. By the combination of such gas outlet and seal tape,
The burst pressure of the sealing tape is adjusted in two stages.

An opening having a diameter of 3 mm has an area of 0.71 cm ² ,
Opening of diameter 2mm has an area of 0.31 cm ^2, the total opening area to be 10 respectively is 10.2 cm ^2. The opening diameter ratio of the openings whose diameters are adjacent is 1.5. The opening area ratio is 2.29 / 1.

In this structure, when the gas generator operates, for example, after the igniter is turned on to ignite the seven-hole gas generating agent in the combustion chamber 5a, the single-hole gas generating agent in the combustion chamber 5b is ignited at a time such as 30 msec. When the igniter is activated, the opening area (hole diameter and number of holes) of the gas outlet 26a is correlated with the combustion surface area of the gas generating agent in the combustion chamber 5a, and the opening area (hole diameter and number of holes) of the gas outlet 26b is determined. ) Is correlated with the combustion surface area of the gas generating agent in the combustion chamber 5b. Conventionally, there was only one type of hole with an outlet, so either the opening area was correlated with the surface area of the gas generating agent in the combustion chamber 5a, or was correlated with the surface area of all gas generating agents in the combustion chambers 5a and 5b. It was only possible in
In this case, the former is optimal in condition when the gas generating agent in the combustion chamber 5a burns, but the combustion pressure is increased when the gas generating agent in the combustion chamber 5b or the combustion chambers 5a and 5b continues to burn. High and can result in an overpowered gas generator. In the latter case, when the gas generating agent only in the combustion chamber 5a first burns, the output becomes too moderate on the contrary, and it is difficult to obtain sufficient restraint performance in the initial stage of the airbag deployment.

According to the present invention, as shown in this embodiment, two types of outlets having different opening areas are provided, and by correlating with the surface area of the gas generating agent in each combustion chamber, the ignition of each gas generating agent is performed. Optimal airbag deployment is obtained regardless of timing. Although the opening area of the gas outlet is two types here, it is also possible to suppress the difference in output performance due to the environmental temperature by further increasing the types and adjusting the burst pressure of the seal tape in multiple stages. Such effects according to the present invention can be confirmed by, for example, the following tank combustion test. <Tank combustion test> A gas generator for an air bag is fixed in a SUS (stainless steel) tank having an internal volume of 60 liters, the tank is sealed at room temperature, and then connected to an external ignition electric circuit. The pressure rise change in the tank is measured for a period of time from 0 to 200 milliseconds by setting a time when the ignition electric circuit switch is turned on (ignition current is applied) to 0 by a pressure transducer installed separately in the tank. Each measurement data is finally processed as a tank pressure / time curve by computer processing.
A curve for evaluating the performance of the molded article of the gas generating agent (hereinafter referred to as “tank curve”) is obtained. After the completion of the combustion, a part of the gas in the tank may be extracted and used for gas analysis of CO and NOx.

In the gas generator formed as described above, when the first igniter 12a disposed inside the ignition means accommodating chamber 8 and outside the separation tube 14 is operated, the first transfer charge accommodating agent is provided. Room 15a
The transfer charge 16a housed therein ignites and burns, and the flame passes through the transfer hole 17 of the inner cylinder member 4 and has a porous cylindrical shape having seven holes housed in the first combustion chamber 5a. One gas generating agent 9a
To burn. The second igniter surrounded by the separation tube 14
When 12b operates, the transfer charge 16b contained in the second transfer charge storage chamber 15b is ignited and burns, and the flame is generated in the second combustion chamber 5b.
The single-hole cylindrical second gas generating agent 9b housed in b is ignited and burned. As a result, the igniter (12a, 12b) depends on whether to activate the first igniter and then activate the second igniter, or to activate the first and second igniters simultaneously.
By adjusting the ignition timing of the gas generator, the output form (operating performance) of the gas generator can be arbitrarily adjusted. The deployment of the airbag in such a case can be maximized. Particularly, in the gas generator shown in this figure, a gas generating agent (9a, 9b) having a different shape is used for each combustion chamber (5a, 5b), and the first combustion chamber 5
A contains a first gas generating agent 9a in a porous cylindrical shape, and the second combustion chamber 5b contains a second gas generating agent 9b in a single-hole cylindrical shape. Also, the amount of the gas generating agent contained in each combustion chamber (5a, 5b) is different, and 35 g of gas generating agent (9a, 9b) in the first combustion chamber 5a and 6g in the second combustion chamber 5b. ) Are accommodated. As a result, in this gas generator, the output form can be adjusted more accurately.
The shape, composition, composition ratio, amount and the like of the gas generating agent can of course be appropriately changed in order to obtain a desired output form.

According to the present invention, such a combination of two or more igniters and two or more types of gas discharge ports makes it possible to equalize the internal pressure during operation of the gas generator and to stabilize combustion performance. .

The gas generator shown in FIG. 2 has the same structure as that shown in FIG. 1 except that the structure of a gas outlet provided in a diffuser shell of a housing and a seal tape for closing the gas outlet are changed. The same members as those described above are denoted by the same reference numerals, and description thereof will be omitted. That is, in FIG. 2, in order to adjust the burst pressure of the seal tape in two stages, the opening area (hole diameter and number of holes) of each gas outlet is the same, but the thickness of the seal tape is changed. It is. It has 20 openings 26a and 26b having a diameter of 3 mm, and 14 and 16 seal tapes 27a each composed of an aluminum layer of 80 microns and an adhesive layer of 50 microns.
In a gas generator in which the opening is blocked by six sealing tapes 27b consisting of an aluminum layer of 0 micron and an adhesive layer of 50 micron, the thickness ratio is 1.61 / 1 and the opening area corresponding to each thickness is 1.61 / 1. The ratio is 70/30. In this case, the gas outlet 26a and the gas outlet 26b are arranged vertically in the housing axial direction, and the thickness of the seal tape 27b that closes the gas outlet 26b is smaller than the thickness of the seal tape 27a that closes the gas outlet 26a. The thickness is increased. However, the thickness of the sealing tape is regulated in order to adjust the output performance (operating performance) of the gas generator. Adjustment of the internal pressure of the housing during combustion of the gas generating agent depends on the opening of the gas outlet. Adjusted by area. That is, this seal tape does not affect the maximum internal combustion pressure. The gas discharge ports 26a and 26b have the same opening area (hole diameter and number of holes). In this case, for example, when the gas generating agent 9a in the combustion chamber 5a is
As all the sealing tape 27a covering 26a is ruptured,
The opening area of the outlet 26a and the thickness of the sealing tape 27a are adjusted. Subsequently, when the gas generating agent 9b in the combustion chamber 5b burns, or when the gas generating agents 9a, 9b in the combustion chambers 5a and 5b burn simultaneously, a higher combustion internal pressure is generated.
At that time, sealing tape 27 covering all outlets 26a, 26b
Seal tape thickened so that a and 27b burst
Attach 27b to the outlet 26b. That is, since the thickness of the seal tape 27a of the gas discharge port 26a is adjusted to be ruptured by the combustion of the gas generating agent 9a only in the combustion chamber 5a, the discharge tape 26a
There is no rupture up to the seal tape 27b of b. Therefore, since the surface area of the gas generating agent in the combustion chamber 5a is correlated with the opening area of only the outlet 26a, it exhibits optimal combustion. When the gas generating agent 9b in the combustion chamber 5b burns later,
Alternatively, when the gas generating agents 9a and 9b in both combustion chambers burn at the same time, a higher combustion pressure is generated.
Rupture up to the seal tape 27b, to suppress the rise in internal pressure,
Optimal airbag deployment is possible regardless of the ignition timing. Also in this case, as described with reference to FIG. 1, the material and structure of the seal tape, the way of arranging the discharge ports, and the like are not limiting factors for obtaining the intended effect, and any specifications are possible. Also, by changing the thickness in multiple stages, a gas generator which is similarly less affected by environmental temperature and the like can be obtained.

In these two embodiments shown in FIGS. 1 and 2, only the opening area of the discharge port or only the thickness of the sealing tape is changed to some kinds, respectively. Adjustments are also possible. Embodiment 2 FIG. 3 is a longitudinal sectional view showing another embodiment of the gas generator for an air bag of the present invention. This gas generator has a structure particularly suitable for being arranged on the passenger side.

The gas generator shown in this figure has a cylindrical shape whose axial center length is longer than the outermost diameter, and has an ignition operated by impact in a housing 103 having a plurality of gas outlets on its peripheral wall. Means, a gas generating agent (9a, 9b) which is ignited and burned by the ignition means to generate a combustion gas for inflating the airbag, and cooling and / or purifying the combustion gas generated by combustion of the gas generating agent And a coolant / filter 122. And housing 1
The two combustion chambers (105a, 105b) provided in 03 are provided coaxially adjacent to the housing 103 in the axial direction.
A communication hole 110 is provided to allow the combustion chambers (105a, 105b) to communicate with each other.

The gas generator shown in the present embodiment has an axially long shape because the housing has a cylindrical shape that is long in the axial direction. , Two combustion chambers (105a, 105b) as described above
Are provided coaxially adjacent to each other to enable communication between the two combustion chambers, so that the operation output of the gas generator and the timing of the output increase can be arbitrarily adjusted, but the structure is simple and easy to manufacture. It becomes a gas generator.

The igniting means includes two or more igniters operated by impact, and each igniter (12a, 1a
2b) is provided in one initiator collar 113 in parallel with each other, so that its assembly is easy.

In the housing 103, a substantially cylindrical coolant filter 122 is provided so as to face the inner peripheral surface of the housing in which a plurality of gas outlets 126a and 126b are formed. A predetermined gap 125 is provided between the inner circumference and the inner circumference. A first combustion chamber 105a is defined adjacent to a space in which the coolant / filter 122 is accommodated, and ignition means including two igniters (12a, 12b) It is arranged coaxially adjacent to the combustion chamber 105a. Since the annular second combustion chamber 105b is defined in the radial direction of the ignition means, the first combustion chamber 105a and the second combustion chamber 105b are adjacent to each other in the axial direction of the housing 103. It will be provided as. The first and second combustion chambers are filled with different gas generating agents (9a, 9b), respectively, and in the gas generator shown in this figure, the first combustion chamber 105a has a porous cylindrical shape. The first gas generating agent 9a and the second combustion chamber 105b contain a single-hole cylindrical second gas generating agent 9b, respectively.

The ignition means is ignited and burned by the operation of the igniters (12a, 12b), and the flame generates a gas generating agent (105a, 105b).
The ignition charge of b) is included, and this ignition charge is defined for each igniter, and ignites and burns independently for each igniter. The space for accommodating the transfer charge defined for each igniter is defined by a cylindrical member, and the first transfer charge storage chamber for storing the first transfer charge 116a.
115a communicates with the first combustion chamber 105a through a heat transfer hole 119 of a partition wall 107 disposed between the ignition means and the first combustion chamber 105a, and a second transfer charge 116b is accommodated therein. The charge storage chamber 115b
A communication hole 117 formed in the tubular member 104 defining the storage chamber 115b communicates with the second combustion chamber 105b. The first combustion chamber 105a and the second combustion chamber 105b communicate with each other through a through hole 110 formed in the partition 107.

In the gas generator shown in this figure, when the first igniter 12a operates, the charge 1 in the first charge storage chamber 115a is charged.
16a is ignited and burns, and the flame is transferred to the
Through 9, the gas generating agent 9 a arranged in the first combustion chamber 105 a is ignited and burned to generate combustion gas. This combustion gas is purified and cooled while passing through the coolant filter 122, and is discharged from the gas outlet. On the other hand, when the second igniter 12b operates, the transfer charge 116b in the second transfer charge storage chamber 115b is ignited and burned, and the flame causes the second charge transfer chamber 116b to move into the second combustion chamber.
The gas generating agent 9b in 105b is ignited and burned. The combustion gas generated in the second combustion chamber 105b passes through the through hole 110 of the partition 107, passes through the first combustion chamber 105a, and is purified and cooled while passing through the coolant filter 122, Released from gas outlet. Also, in the gas generator shown in this figure, the through-hole 110 communicating the first combustion chamber and the second combustion chamber is ruptured only by the combustion of the gas generating agent in the second combustion chamber. Is closed by the sealing tape 111.
In this embodiment, as in the gas generator of FIG. 1, the gas outlets are the large-diameter gas outlet 126a and the small-diameter gas outlet 12a.
6b are provided, which are closed by a seal tape 127. That is, in the embodiment shown in FIG. 3, the thickness of the sealing tape is made constant and the opening area of the gas discharge port is made two kinds as shown in FIG. The optimum output can always be adjusted regardless of the combustion timing of the 105b gas generating agents 9a and 9b. The gas outlet is on the peripheral wall of the cylindrical housing,
Surface area of gas generating agent 9a in combustion chamber 105a and gas outlet 126a
And the surface area and outlet 12 of the gas generating agent 9b in the combustion chamber 105b.
The opening area of 6b is correlated. The principle of operation is the same as in FIG. 1, and a detailed description is omitted.

Further, a defining member 160 that defines the first combustion chamber 105a and a space in which the coolant / filter 122 is accommodated is provided with a communication hole 161 that communicates the two chambers. The combustion gas generated in the second combustion chamber (105a, 105b) passes through the communication hole 161 and the coolant / filter 122
To reach the accommodation space. In this embodiment, a communication hole 161 having a size substantially equal to the inner diameter of the coolant / filter 122 is formed in the defining member 160. And the gas generating agent 9a in the first combustion chamber 105a is
A wire mesh 162 is provided so as not to move toward the space where the coolant / filter 122 is accommodated during the combustion. The wire mesh 162 is a mesh having a size that can prevent the movement of the first gas generating agent 9a during combustion, and may be of any type as long as it does not have ventilation resistance to control combustion performance. Absent.

As described above, also in the gas generator of this embodiment, the gas generating agents (9a, 9b) housed in the respective combustion chambers (105a, 105b) operate the two igniters (12a, 12b). By adjusting the timing, ignition and combustion are performed independently, and the output form (operating performance) of the gas generator can be arbitrarily adjusted. As a result, in various situations such as the speed of the vehicle at the time of the collision and the environmental temperature, the deployment of the airbag in the case of the airbag device described below can be maximized.

In FIG. 3, 2 is provided in the housing.
The two combustion chambers are provided so as to be axially and radially adjacent to the housing. Specifically, in the gas generator shown in FIG. 3, after the partition 107 that defines the first combustion chamber 105a, the ignition means, and the second combustion chamber 105b is bent in the axial direction, The second combustion chamber 105b is expanded in the axial direction of the housing by making the front end into a flange shape and abutting the inner periphery of the housing. As a result, in the gas generator shown in FIG. 3, the second combustion chamber expands in the axial direction, that is, protrudes toward the first combustion chamber, so that the first combustion chamber and the second combustion chamber Are adjacent in the axial and radial directions of the housing. Since the gas generator shown in FIG. 3 can increase the volume of the second combustion chamber, it is convenient when a large amount of the second gas generating agent is used.

FIG. 4 is a sectional view of an embodiment of a gas generator for restraining mainly a passenger in the passenger seat similarly to FIG. 3, and as shown in FIG. An example is shown in which the burst pressure is adjusted by changing the thickness of the burrs. That is, the gas outlet 126a and the gas outlet 126b are arranged vertically in the housing axial direction, and the thickness of the seal tape 127b that closes the gas outlet 126b is greater than the thickness of the seal tape 127a that closes the gas outlet 126a. Is thicker. Gas outlet 12
The opening areas (hole diameter and number of holes) of 6a and 126b are the same. In the operation of the gas generator shown in FIG. 4, the same members as those in FIG. 3 are denoted by the same reference numerals, and description thereof will be omitted. The configuration and operation of the gas discharge port and the seal tape are the same as those in FIG. 2, and the description of those operations will be omitted.

Similarly, in the case of the gas generator for restraining the occupant in the passenger seat shown in FIGS. 3 and 4, by further increasing the type of the opening area of the discharge port or the type of the thickness of the sealing tape, Finer adjustment is possible to make it less affected by temperature and the like. Of course, the outlet opening area and the thickness of the sealing tape may be combined at the same time. Embodiment 3 FIG. 5 is a longitudinal sectional view showing a gas generator for an airbag according to another embodiment of the present invention. The gas generator shown in this embodiment also has a structure particularly suitable for being arranged in the driver's seat, similarly to the gas generator shown in FIGS.

The gas generator shown in FIG. 5 has the same structure as that shown in FIG. 1 except for the structure of a partition that defines a second combustion chamber and an ignition means accommodating chamber inside the inner cylinder member. Therefore,
The same members as those in FIG. 1 are denoted by the same reference numerals, and description thereof will be omitted.

In particular, in the gas generator shown in this figure, a substantially flat circular partition 307 that defines the inside of the inner cylinder member as a second combustion chamber and an ignition means accommodating chamber is shown in an exploded perspective view of FIG. As described above, the partition circular member which is locked to the stepped portion 306 of the inner cylindrical member 304
350 and a seal cup member engaged with the section circular member 350
It consists of 360 and.

The partitioning circular member 350 has a substantially flat circular shape, and has a charge transfer agent receiving portion 3 of a seal cup member 360 described later.
Opening 351 to fit 61 inside, and the bottom is hollowed out in a circular shape,
It has a circular hole 352 for accommodating the upper part of the igniter 312b, and a second heat transfer hole 319 penetrating substantially at the center of the circular hole. In addition, the seal cup member 360 fits into the opening 351 of the section circular member 350 to fit in the second combustion chamber 305b.
A cylindrical igniter accommodating portion 361 projecting inward and a cylindrical igniter accommodating portion formed at a position facing the circular hole portion 352 of the sectioned circular member 350 and extending on the opposite side to the igniting agent accommodating portion 361. Mouth 362
And The first transfer charge 316a is stored inside the transfer charge storage section 361, and the igniter storage opening 36 is also provided.
2, a second igniter 312b is fitted therein. The partitioning circular member 350 and the seal cup member 360 are engaged by fitting the transfer charge accommodating portion 361 of the seal cup member 360 into the opening 351 of the partitioning circular member 350. The upper part of the second igniter 312b fitted inside is a section circular member 35.
It projects into the 0 circular hole 352.

The circular section 350 and the seal cup member 360
As shown in FIG. 5, the partition wall 307
Is locked by a stepped notch 306 formed on the inner peripheral surface of the base. That is, the periphery of the sectioned circular member 350 is supported by the stepped portion 306,
The seal cup member 360 is supported in contact with the section circular member 350. The periphery of the seal cup member 360 is formed by bending in the same direction as the igniter accommodating port 362, and the bent portion 363 fits into a groove 364 provided on the inner peripheral surface of the inner cylinder member 304. ing. As a result, the circular section 350 is supported by the seal cup member 360, and the axial movement of the housing 3 is prevented. Further, by fitting the bent portion 363 of the peripheral edge of the seal cup member 360 into the groove 364 on the inner peripheral surface of the inner cylinder member 304, the partition wall 307 (that is, the seal cup member 360) and the inner cylinder member 304 are engaged without any gap. I agree. Therefore, in the inner cylindrical member 304, the ignition means accommodating chamber 308 provided on the closure shell 2 side and the second combustion chamber 305b provided on the diffuser shell 1 side include the seal cup member 360, the groove 364, Is reliably partitioned by the ignition means seal structure composed of the combination of

The igniter accommodating port 362 formed in the seal cup member 360 has a skirt portion opened in a skirt shape, and the inside thereof, that is, the second igniter 312 accommodated in the accommodating port 362 is provided.
An O-ring 381 is arranged between the second igniter 312b and the housing 362, and an O-ring 381 is provided between the housing 362 and the second igniter 312b. Since the O-ring 381 also presses against the igniter fixing member 382 for fixing the two igniters 312a and 312b to the single initiator collar 313, the second igniter 312b is Are arranged in a space defined by a circular hole portion 352, an igniter accommodating port 362 of the seal cup member, an O-ring 381, and an igniter fixing member 382. In this partitioned space, the second igniter 312b is operated, so that the second heat transfer hole 319 formed in the circular hole 352 of the partitioned circular member 350 is formed.
The sealing tape 320 that ruptures the second combustion chamber 305
Communicate with b. And the first igniter 312a and the second igniter 3
12b is securely separated from each other by a seal structure (hereinafter, referred to as an “igniter seal structure”) including a skirt portion of an igniter accommodating port 362, an O-ring 381, and an igniter fixing member 382.
Thus, the flame generated by the operation of any one of the igniters does not directly flow into the space in which the other igniters are accommodated. The igniter fixing member 382 is the initiator color 3
13 is formed so as to cover the upper surface of the igniter, and has a hole 384 for inserting the upper part of each igniter and supporting the shoulder 383.
Two igniters 312a arranged on the initiator collar 313,
312b is fixed to an igniter fixing member 382 which is fitted to the initiator collar 313. Such an igniter fixing member 382
, The two igniters 312a and 312b can be easily combined with the initiator collar 313.
In the gas generator shown in this embodiment, the first igniter 312a and the second igniter 312b are formed to have different sizes and have different operation outputs. Alternatively, an igniter of the same operating power can be used.

In the gas generator shown in FIG.
As in the gas generator shown in (1), the plurality of gas outlets (26a, 26b) formed in the housing are controlled to have two or more kinds of opening diameters and / or opening areas. As a result, it is possible to suppress the difference in the maximum internal pressure of the housing when each of the ignition means is activated, to equalize the internal pressure when the gas generator is activated, and to provide a gas generator for an airbag with stable combustion performance. Also, in the gas generator according to this embodiment, similarly to the gas generator shown in FIG. 2, the opening area of each gas outlet is fixed, and the sealing tape 27 is used.
By adjusting the burst pressure by changing the thickness of the shut-off means, etc., the difference in the maximum internal pressure of the housing when each ignition means is activated can also be suppressed. Further, it is of course possible to use both the control of the opening diameter and / or the opening surface of the gas discharge port and the control of the thickness of the blocking means. Fourth Embodiment FIG. 7 is a longitudinal sectional view showing a gas generator for an airbag according to another embodiment of the present invention. The gas generator shown in this embodiment has a structure particularly suitable for being arranged in the driver's seat, similarly to the gas generators shown in the first and third embodiments.

In particular, the gas generator shown in this embodiment is:
It is characterized by the arrangement of the two combustion chambers provided in the housing and the forming method.

Also in the present embodiment, the gas outlet 410 formed in the diffuser shell 401 is provided with two types of gas outlets 410a and 410b having different diameters. Gas generating agent 452 due to environmental effects
It is closed with a seal tape 429 for protecting the.
Two types of gas outlets 410 with different inner diameters (and opening areas)
By providing a and 410b, the internal combustion pressure in the housing 403 during operation can be equalized (combustion performance is stabilized). Since this operation has already been described in the first embodiment, it is omitted here. Hereinafter, the structure of the gas generator according to the present embodiment will be described.

That is, the gas generator shown in this embodiment has a diffuser shell 4 having a plurality of gas outlets 410.
01 and a cylindrical shell 403 formed by joining a closure shell 402 forming an internal storage space together with the diffuser shell 401 by friction welding, a capsule-shaped inner shell having a circular horizontal cross section and a closed upper end. The 404 is arranged and fixed eccentrically with respect to the center axis of the housing, and the outside is a first combustion chamber 450 and the inside is a second combustion chamber 460.

The degree of eccentricity of the inner shell 404 disposed in the housing 403 with respect to the housing 403 can be appropriately changed according to a desired volume ratio of the combustion chamber, and the structure inside the housing 403, for example, the coolant This is an element that can change depending on the presence or absence of the filter 425 and the like. For example, as shown in the gas generator shown in FIG.
When the coolant / filter 425 is disposed so as to face the peripheral wall surface of No. 3, the coolant / filter 425 can be appropriately selected in the range of 10 to 75%. However, since this numerical range can also vary depending on the size of the igniters (451, 461), this numerical range is different from the inner shell 404 in the gas generator shown in FIG.
It shows a measure of eccentricity.

The inner shell 404 can have various horizontal cross-sectional shapes such as a rectangular shape and an elliptical shape. desirable. In other words, the inner shell 404 is closed by friction welding.
This is because the horizontal cross-sectional shape of the inner shell 404 needs to be circular, and the laser irradiation distance needs to be kept constant even when bonding is performed by laser welding.

As described above, in this embodiment,
The first combustion chamber 450 and the second combustion chamber 460 are inner shells.
Defined by 404. That is, the first combustion chamber 450 is provided outside the inner shell 404, and the second combustion chamber 460
Is provided inside the inner shell 404. The volume ratio between the first combustion chamber 450 and the second combustion chamber 460 (first combustion chamber volume: second combustion chamber volume) is 3.3: 1 in the present embodiment. But also 97: 1 ~
It can be appropriately selected within a range of 1: 1.1. However, the selection range of the volume ratio can be appropriately changed depending on the size of the igniter (451, 461), the shape of the gas generating agent (452, 462), and the like. Accordingly, the above numerical range indicates a range that can be selected in the structure of the gas generator shown in this figure.

As described above, the second combustion chamber 460 and the first combustion chamber 450 separated by the inner shell 404 contain gas generating agents (452, 462), respectively. In the first combustion chamber 450, a first gas generating agent 452 is provided.
Each of the second gas generating agents 462 is accommodated in 460. In the present embodiment, the first gas generating agent 452 and the second gas generating agent 462 have the same shape and the like as the gas generating agent. , Gas generating means having at least one different composition ratio or amount can be accommodated.

The inner shell 404 defining the first combustion chamber 450 and the second combustion chamber 460 is disposed eccentrically with respect to the center axis of the housing 403, and
The second combustion chamber 460 provided inside 4 is also a housing 403
Is eccentric to An igniter is disposed in each of the first combustion chamber 450 and the second combustion chamber 460, and among them, a second igniter 461 disposed in the second combustion chamber 460 is provided.
Is disposed at the center of the second combustion chamber 460 which is eccentric with respect to the central axis of the housing 403. As a result, the flame generated by the operation of the igniter 461 is generated by the second gas generating agent 4.
62 can be evenly burned. The second igniter 461 and the first igniter 451 arranged in the first combustion chamber 450 are both eccentrically arranged with respect to the center axis of the housing 403. By eccentricizing the first and second igniters and the inner shell 404 with respect to the center axis of the housing 403 in this manner, the change in the volume ratio of the first and second combustion chambers can be widened, Also housing 403
Can be minimized in the radial direction.

Of the igniters arranged for each combustion chamber, the igniter 451 arranged in the first combustion chamber 450 has the transfer agent 408 arranged around and upward. This explosive charge 408 is exploded for the convenience of assembling the gas generator, and furthermore, due to shock or vibration received during mounting on the vehicle, the explosive charge 408 is scattered in the first combustion chamber 450 and the first gas generating agent It is housed in a transfer charge container 426 so as not to reduce the ignitability of the 452. The transfer charge container 426 is made of aluminum having a thickness (for example, about 200 μm) which easily ruptures due to the combustion of the transfer charge 408 therein and transmits a flame to the surroundings. On the other hand, a transfer charge such as that arranged in the first combustion chamber 450 is not necessarily required in the second combustion chamber 460. This is because even if the first gas generating agent 452 burns and the pressure in the first combustion chamber 450 rises, the rupture member 407 that blocks the hole 406 of the inner shell 404 described later
Since the internal pressure of the second combustion chamber 460 does not burst unless the internal pressure of the second combustion chamber 450 rises above the internal pressure of the first combustion chamber 450, the second combustion chamber 460 is in a sealed state during this time, the pressure increases during that time, and the second gas generating agent 462 This is because it is easier to ignite than the first gas generating agent 452, but a transfer charge may be used as needed.

In the first combustion chamber 450, a first igniter 451
A cylindrical member 436 is provided so as to surround the radially outer side of the transfer charge 408 arranged above the cylindrical member 408. This cylindrical member 436 has a cylindrical shape with both upper and lower ends open, one end of which is fitted around the outer periphery of the portion to which the igniter 451 is fixed so that no gap is formed, and the other end of which is the ceiling of the diffuser shell 401. It is clamped by a retainer 411 existing near the inner surface and fixed at a predetermined location. A plurality of heat transfer holes 437 are formed on the peripheral wall of the cylindrical member 436, and the flame generated by the combustion of the transfer charge 408 is ejected from the heat transfer holes 437 and exists outside the corresponding member. First gas generant 452
To ignite and burn. The cylindrical member 436 is
It is desirable that the member be made of the same material as 03.

In particular, in the gas generator shown in this embodiment, the first combustion chamber 450 is, as shown in the plan view of FIG.
It has an annular shape approximating a crescent shape with a circular inside punched out, and the first gas generating agent 452 is installed therein. Therefore, in the first combustion chamber 450, the second combustion chamber 4
Unlike 60, the distance between the gas generating agent 452 and the igniter 451 is
It differs depending on the storage location of the gas generating agent 452. Therefore, when the igniter 451 is ignited, the first gas generating agent 452 is ignited.
Irregularities in combustion. Therefore, the direction of the transfer hole 437 provided in the peripheral wall of the inner cylinder member 436 is regulated so that the flame of the transfer agent 408 is oriented in the direction indicated by the arrow in FIG. This causes the second combustion chamber 460 (ie, inner shell 404)
The gas generating agent 452 in the shaded area can also be burned without unevenness. Further, in place of the inner cylinder member 436, in FIG.
A jet direction restricting means (not shown) having a hole in the direction indicated by the arrow can be used. The ejection direction regulating means is provided with first ignition means (in FIG. 7) for igniting the first gas generating agent 452 for the purpose of effectively burning the first gas generating agent 452. Igniter 451 and transfer charge 40
It regulates the direction in which the flame is generated by the operation of 8). The ejection direction regulating means is, for example, a cup-shaped container whose one end is closed by a cylindrical member, and orients the flame of the ignition means in a desired direction (the direction indicated by the arrow in FIG. 8) on the peripheral wall. Provided with a nozzle for this purpose can be used. In this case, the ejection direction regulating means is
Used around the first ignition means. Even in the case of using such an ejection direction restricting means, the first ignition means disposed on the inside thereof includes an igniter and a transfer charge which ignites and burns by the operation of the igniter. It is desirable.

The inner shell 404 defining the first combustion chamber 450 and the second combustion chamber 460 has a capsule shape as described above, and has a plurality of openings 405 formed in the peripheral wall. The opening 405 is opened only by the combustion of the second gas generating agent 462 disposed in the second combustion chamber 460, and the combustion of the first gas generating agent 452 stored in the first combustion chamber 450 is performed. Are formed so as not to be opened. In the present embodiment, this opening 405 is
04 comprises a plurality of holes 406 provided in the peripheral wall and a rupture member 407 closing the holes, and a stainless steel seal tape is used as the rupture member 407. This rupture member 40
7 bursts, only by the combustion of the second gas generant 462,
The hole 406 is opened by peeling, burning, or coming off, and is formed so as not to be ruptured by burning of the first gas generating agent 452.

The inner shell 404 is fixed by connecting the opened lower part 413 to the closure shell 402. When the closure shell 402 includes a collar portion 402a for fixing the igniter, the inner shell 404 can be attached to the collar portion 402a. In the gas generator shown in FIG. 7, the closure shell 402 is formed by integrating a circular collar portion having a size capable of fixing two igniters on the bottom surface of a cylindrical shell 402b joined to the diffuser shell 401. The inner shell 404 is formed by joining the collar portion 402
joined to a. However, the collar portion 402a is formed in a circular shape having a size that can be fixed for each igniter, and
It can be formed integrally with the bottom surface of 2b, or can be formed integrally with the bottom surface of the cylindrical shell 402b. In such a case, the inner shell 404 can be directly attached to the bottom surface of the cylindrical shell portion 402b other than the collar portion 402a of the closure shell.

In the present embodiment, the inner shell 40
The connection between the closure shell 4 and the closure shell 402 can be performed by friction welding, caulking, resistance welding, or the like, or by joining unevenness. In particular, when the two are joined by friction welding, the closure shell 402 is desirably fixed. Accordingly, even if the axes of the inner shell 404 and the closure shell 402 are not aligned, friction welding can be stably performed. In other words, if the inner shell 404 is fixed and the closure shell 402 is rotated to perform friction welding, the center of gravity of the closure shell 402 is displaced from the center of rotation, so that stable friction welding cannot be performed. . Therefore, in the present invention, it is assumed that the closure shell 402 side is fixed and the inner shell 404 side is rotated to perform friction welding. When friction welding, the inner shell
The closure shell 402 is desirably positioned and fixed so that the 404 can always be mounted in a predetermined position. Therefore, this closure shell 40
It is desirable that positioning means is appropriately applied to 2.
In the inner shell 404, a gas generating agent fixing member 414 is disposed for safely and smoothly connecting to the closure shell 402. This gas generating agent fixing member 414
In order to prevent the gas generating agent 462 from directly contacting the inner shell 404 when the inner shell 404 is friction-welded to the closure shell 402, the installation space for the igniter 461 is secured in the space formed by the inner shell 404. Used for the purpose. When the inner shell 404 is attached to the closure shell 402, the inner shell 404 can be attached not only by the above-described friction welding, but also by caulking, resistance welding, or the like, by concavo-convex joining.
By using 4, assemblability is improved. This gas generating agent fixing member 414 is made of aluminum as an example here,
Although a canister having a thickness that is easily ruptured by the combustion of the gas generating agent 462 is used, other suitable members (material, Any shape can be used. In addition, such a gas generating agent fixing member 41
When 4 is not used, the gas generating agent 462 having a single-hole cylindrical shape is solidified in the same shape as the inner space of the inner shell 404 to form a mass of the gas generating agent, and this may be installed in the inner shell 404. it can. In this case, the gas generating agent fixing member 414 may be omitted.

In the present embodiment, the closure shell
The collar portion 402a of the 402 is formed in a size capable of fixing the two igniters 451 and 461 side by side. Thus, if the two igniters 451 and 461 are fixed to the collar portion 402a in advance by caulking or the like, the collar portion 402a is attached to the cylindrical shell portion 40a.
If the closure shell 402 is formed integrally with 2b,
One igniter 451,461 can be fixed to the closure shell 402. In the drawing, the first igniter 451 and the second igniter 4
Although 61 is described in the same size, they may have different outputs for each combustion chamber.
Further, in this embodiment, the cables 415 for connecting the igniters 451 and 461 and transmitting the operation signal are drawn in the same direction.

In the housing 403, a coolant filter 425 is provided as filter means for purifying and cooling the combustion gas generated by the combustion of the gas generating agent. The gas generated by the combustion of the first and second gas generating agents passes through the coolant filter 425 together. When this combustion gas prevents a short path passing between the end face of the coolant filter 425 and the inner surface of the ceiling of the diffuser shell 401, the coolant filter is provided by a tubular short path prevention member having an inward flange. The upper and lower inner peripheral surfaces of the 425 and the inner surface of the housing can also be covered. In particular, in the gas generator shown in FIG. 7, a coolant filter 425 having a self-tightening structure whose upper and lower end surfaces are inclined so as to be narrowed outward in the radial direction is used. The self-tightening type coolant / filter 425 will be described later with reference to FIG. Also in this embodiment, similarly to the gas generator of FIG. 1, a gap 428 serving as a flow path of combustion gas is formed outside the coolant / filter 425.

As described above, in the gas generator shown in FIG.
The igniters 451 and 461 and the inner shell 404 are
It is arranged eccentrically to 3. In such a gas generator, when the diffuser shell 401 and the closure shell 402 are joined by friction welding, the joint between the two shells is stabilized by fixing the closure shell 402 and performing friction welding. You can do it. In particular, when the inner shell 404 is directly attached to the closure shell 402 by friction welding, as shown in FIG. 7, a flange portion 432 for attaching the gas generator to the module case is provided on the closure shell 402 side. Part 4
It is desirable to form a positioning part by cutting out the periphery of a part constituting the part 32, for example, the protruding part 433 or the like. When formed in this manner, the closure shell 402 is always fixed in a fixed direction based on the positioning portion.
The inner shell 404 can be securely attached to a predetermined position.

In the gas generator formed as described above, when the first igniter 451 disposed in the first combustion chamber 450 provided outside the inner shell 404 operates, the combustion chamber 4
The first gas generating agent 452 in 50 ignites and burns to generate combustion gas. A slight gap is provided between the inner shell 404 and the coolant / filter 425, and this gap creates a gas flow between the coolant / filter 425 and the inner shell 404. The combustion gas can use the entire surface of the filter 425 effectively. This combustion gas is purified and cooled while passing through the coolant filter 425, and then discharged from the gas outlet 410.

On the other hand, when the second igniter 461 arranged in the inner shell 404 operates, the second gas generating agent 462 ignites and burns to generate combustion gas. This combustion gas opens the opening 405 of the inner shell 404, and the opening 40
From 5, it flows into the first combustion chamber 450. Thereafter, the gas passes through the coolant / filter 425 in the same manner as the combustion gas of the first gas generating agent 452, and is discharged from the gas discharge port 410. The sealing tape 429 closing the gas outlet 410 is
It bursts due to the passage of the combustion gas generated in 403. The second gas generating agent 462 is ignited and burned by the operation of the second igniter 461, and does not directly burn by the burning of the first gas generating agent 452. This is the inner shell
This is because the opening 405 of the 404 is opened only by the combustion of the second gas generating agent 462, and is not opened by the combustion of the first gas generating agent 452.

The gas generator formed as described above activates the first igniter 451 and then activates the second igniter 461 or the first igniter 451 and the second ignition By adjusting the ignition timing of the two igniters, for example, by operating the gas generator 461 at the same time, the output form (operating performance) of the gas generator can be arbitrarily adjusted. In various situations such as temperature, the deployment of the airbag in the case of the airbag device described later can be maximized. In particular, in the gas generator shown in FIG. 7, since the two combustion chambers are provided side by side in the radial direction, the height of the gas generator can be minimized.

In the gas generator shown in FIG.
As in the case of the gas generator shown in (1), since the opening diameter and / or opening area of the plurality of gas outlets 410 formed in the housing 403 are controlled to two or more types, each ignition means is activated. The difference in the maximum internal pressure of the housing at the time can be suppressed, the internal pressure at the time of the operation of the gas generator is equalized, and the gas generator for an airbag with stable combustion performance can be obtained. Also, in the gas generator according to this embodiment, each gas outlet is provided similarly to the gas generator shown in FIG.
By keeping the opening area of 410 constant and changing the thickness of the blocking means 429 such as sealing tape to adjust the burst pressure, the difference in the maximum internal pressure of the housing when each ignition means is activated is suppressed. Can also. In addition, gas outlet 41
Control of the opening diameter and / or opening surface of 0 and the product blocking means 429
It is of course possible to use the thickness control together. [Other Embodiments] The gas generator for an air bag shown in the above-described first to fourth embodiments may optionally have the structure shown in FIGS. <Embodiment Regarding Through Holes Between Combustion Chambers> FIG. 9 shows another embodiment of an opening which is opened by the combustion of the second gas generating agent and communicates the first combustion chamber and the second combustion chamber. Is shown.

That is, FIG. 9A shows that the opening 505 formed in the partition wall 504 (including the inner shell) defining the first combustion chamber 550 and the second combustion chamber 560 has an appropriate shape from the outside. An embodiment is shown in which a shielding plate 590, for example, a band-shaped member is covered with an annularly formed shielding plate or the like so that the combustion flame of the first gas generating agent does not come into direct contact. Reference numeral 522 indicates a second gas generating agent. FIG. 9B shows an embodiment in which a notch 512 is formed on the peripheral wall of the partition 504 to form an opening 505. Further, FIG.
An embodiment in which the opening 505 is formed by partially reducing the thickness of the peripheral wall of 04 is shown.

Therefore, in the gas generator shown in the first to fourth embodiments, the opening communicating the first combustion chamber and the second combustion chamber is formed in the mode shown in FIG. And the second combustion chamber can be communicated. <Embodiment of Positioning Structure for Igniter and Cable> FIG.
Shows a positioning structure for the two igniters used in the first to fourth embodiments and a cable connected to transmit an operation signal to each igniter.

That is, the gas generators shown in the first to fourth embodiments are configured to include two igniters.
This igniter has a cable 515 for transmitting the activation signal.
Is connected. In the gas generators described in the first to fourth embodiments, the cable 515 may transmit a different operation signal in order to adjust the operation timing of each igniter. In this case, if a different cable 515 is mistakenly connected to one of the igniters, a desired operation output cannot be obtained. If an igniter is provided with a positioning means so that it can be connected to only one of the cables 515, a connection error can be prevented. Such positioning means can be achieved, for example, by using different types of connectors 516 for each igniter, as shown in the main part enlarged views of FIGS. In the positioning means shown in FIG. 10a, a positioning groove (or projection) 517 is formed in the connector 516, and the position of the projection (or groove) 518 corresponding to the positioning groove (or projection) 517 is
Each igniter 538 is different. That is, when attaching the connector 516 to the gas generator, if the connector 516 is not attached in the correct direction, the connectors will interfere with each other, and the position of the groove (or projection) 517 of each connector 516 will be adjusted so that the connector cannot be properly attached. Frog.
In the positioning means shown in FIG.
A groove (or projection) 519 for positioning is provided only on 21. That is, a connector 521A provided with a groove (or projection) 519.
The igniter 522b on the side where the protrusion (or groove) 520 is not provided
However, the connector 521B having no groove (or protrusion) 519 cannot be connected to the igniter 522a having the protrusion (or groove) 520. As a result, an erroneous connection of the connector 521 can be easily noticed during assembly. In FIG. 10c, the shape of the connecting portion 523 of each connector 539 is different. In FIG. 10d, two connectors are combined into one, and a positioning groove (or projection) 524 is further formed. As the positioning means, other means for eliminating a connection error of the connector can be appropriately implemented.

As described above, in the gas generator shown in the first to fourth embodiments, when the positioning means for specifying the cable 515 connected to each igniter is provided, the gas generation A gas generator for an airbag which can more reliably adjust the operation of the device is realized.

As shown in FIG. 10, the lead wires connected to the respective igniters can be pulled out on the same plane and in the same direction. In particular, as shown in this figure, it is preferable that the lead wires are connected via connectors, and the connectors are arranged in parallel on the same plane. In this connector, it is desirable that each lead wire be drawn in the same direction as the direction orthogonal to the axial direction of the housing. <Embodiment of Coolant Filter> FIG.
Relates to the structure of a coolant filter 530 disposed in the housing and for purifying and / or cooling the combustion gas generated by the combustion of the gas generating means, and in particular, in relation to the shape of the housing inner surface 531, A coolant filter having a self-tightening structure capable of preventing a short path through which combustion gas passes between the filter and the filter 530
About 530.

That is, the upper and lower end surfaces of the coolant / filter 530 are inclined so as to be narrowed outward in the radial direction, and are disposed in the housing in contact with the upper and lower inner surfaces of the housing. At this time, it is desirable that the upper and lower inner surfaces 531 of the housing are also formed so as to be inclined in accordance with the inclination of the upper and lower end surfaces of the coolant filter 530. As a result, the coolant filter 530 pushed radially outward by the combustion gas
The upper and lower end surfaces thereof abut against the housing inner surface 531 to prevent a short path of the combustion gas between them. <Embodiment of automatic ignition material (AIM)> FIG.
In the second combustion chamber, an auto-ignition material (AI) ignited by the heat of combustion of the first gas generating agent 309a transmitted from the housing 1 or the like.
8 shows an airbag gas generator of an embodiment accommodating M) 385. The gas generator shown in this embodiment burns only the first gas generating agent 309a, and the second gas generating agent 309b disposed in the second combustion chamber 305b is used after the gas generator is operated. If it remains as it is, use this as the first gas generating agent.
It is intended to indirectly burn due to the combustion of 309a. Therefore, this embodiment is referred to as the third embodiment.
A description will be given based on the gas generator for an airbag shown in FIG.

That is, also in the gas generator for an air bag shown in the third embodiment, the first gas generating agent 309a is normally operated by the operation of the first igniter 312a and the second gas generating agent 309a. The agent 309b is ignited and burned independently by the operation of the second igniter 312b, but in some cases, the first igniter 312a
There is a case where an electric current is supplied to only the first combustion chamber 305a to ignite and burn only the gas generating agent 309a in the first combustion chamber 305a. That is, this is a case where the second gas generating agent 309b and the second igniter 312b are left without burning. In such a case,
Since it causes inconvenience at the time of disposal, etc., after the operation of the gas generator (only the first igniter 312a), the normal delayed ignition timing for operating the second igniter 312b (for example, 10 to 40 milliseconds) It is desirable that the gas generating agent 309b in the second combustion chamber 305b be burned with a further delay (for example, 100 milliseconds or more). Therefore, as shown in FIG. 12, an auto-ignition material 385 that ignites and burns by conduction of combustion heat of the first gas generating agent 309a can be arranged in the second combustion chamber 305b. In this case, the ignition of the second gas generating agent 309b by the auto-ignition material 385 is delayed for a predetermined time after the operation of the first igniter 312a, and the normal delay time when the second igniter 312b is operated. This is performed after a sufficient time elapses (that is, the operation interval between the igniters). That is, for the purpose of adjusting the operation performance of the gas generator, the combustion of the second gas generating agent 309b is delayed (that is, the second igniter 31).
2b). A second gas generant 309b is ignited and burned by the autoignition material 385, optionally while delaying the actuation current to the second igniter 312b to adjust the gas generator's operating performance. Not even. Note that the automatic ignition material 385 can be arranged in combination with the second igniter.

Particularly, this embodiment is different from the third embodiment.
Although the description has been given based on the gas generator shown in the above, naturally, also in the gas generators shown in the first, second and fourth embodiments, the above-mentioned auto-ignition material can be arranged in the second combustion chamber. . In this case, even if the second gas generating agent remains after the operation of the gas generator, the second gas generating agent is burned by conduction of heat generated by the burning of the first gas generating agent. It becomes possible. Fifth Embodiment FIG. 13 shows an embodiment of the airbag apparatus according to the present invention in the case of including a gas generator using an electric ignition type ignition means.

This airbag device is composed of a gas generator 200
, An impact sensor 201, a control unit 202, a module case 203, and an airbag 204. As the gas generator 200, the gas generator described with reference to FIG. 1 is used, and its operation performance is adjusted in the initial stage of the gas generator operation so as to minimize impact on the occupant. ing.

The impact sensor 201 can be composed of, for example, a semiconductor acceleration sensor. In this semiconductor type acceleration sensor, four semiconductor strain gauges are formed on a beam of a silicon substrate which is deflected when acceleration is applied,
These semiconductor strain gauges are bridge-connected.
When acceleration is applied, the beam deflects, causing strain on the surface. Due to this strain, the resistance of the semiconductor strain gauge changes, and the change in resistance is detected as a voltage signal proportional to the acceleration.

The control unit 202 includes an ignition determination circuit, and a signal from the semiconductor acceleration sensor is input to the ignition determination circuit. When the shock signal from the sensor 201 exceeds a certain value, the control unit 202 starts the calculation. When the calculation result exceeds a certain value, the control unit 202 outputs an operation signal to the igniter 12 of the gas generator 200.

The module case 203 is made of, for example, polyurethane, and includes a module cover 205. The module case 203 houses the airbag 204 and the gas generator 200 and is configured as a pad module. When the pad module is mounted on the driver's seat side of an automobile, the pad module is usually mounted on the steering wheel 207.

The airbag 204 is formed of nylon (eg, nylon 66) or polyester, and the bag opening 206 surrounds the gas outlet of the gas generator, and is fixed to the flange of the gas generator in a folded state. Have been.

When a semiconductor type acceleration sensor 201 detects a shock at the time of a vehicle collision, the signal is sent to the control unit 202, and when the shock signal from the sensor exceeds a certain value, the control unit 202 starts calculation.
When the calculated result exceeds a certain value, an operation signal is output to the igniter 12 of the gas generator 200. Thereby, the igniter 12 operates to ignite the gas generating agent, and the gas generating agent burns to generate gas. This gas is blown into the airbag 204, whereby the airbag breaks the module cover 205 and bulges, forming a cushion between the steering wheel 207 and the occupant to absorb impact. Embodiment 6 FIG. 14 is a longitudinal sectional view showing another embodiment of the gas generator for an air bag of the present invention. The gas generator shown in this figure also has a structure particularly suitable for being arranged on the driver's seat side. However, the flow path forming member 51 is disposed in the first combustion chamber 5a, and the combustion gas generated in the second combustion chamber 5b is provided between the flow path forming member 51 and the diffuser shell ceiling inner surface 28. The passage 52 that passes is formed.

The flow path forming member 51 is an annular shape in which the inner and outer peripheries of the circular member are bent to form an inner peripheral wall 53 and an outer peripheral wall 54. A circular portion 55 connecting both peripheral wall surfaces has a diffuser shell ceiling. A support wall 56 for securing a space between the inner wall 28 and the inner surface 28 is integrally formed. The flow path forming member 51 sandwiches the inner cylindrical member 4 with the inner peripheral wall 53 and abuts the support wall 56 on the inner surface 28 of the diffuser shell ceiling to form the circular portion 55 and the diffuser shell ceiling inner surface 28. A certain space is secured between them. Since a large number of through holes 57 are formed in this support wall, the space is
Can function as The gas flow path 52 communicates with the second combustion chamber 5b through the through hole 10 of the inner cylinder member 4 by burning the gas generating agent 9b in the second combustion chamber 5b. The combustion gas generated in the chamber 5b
Is discharged into the gas flow path 52, passes through the coolant / filter 22, and is discharged from the gas discharge port 26.

[0096]

The structural requirements and functions described above are 2
The present invention can be implemented by combining two or more.

According to the present invention, while reducing the overall size of the container and having a simple structure to facilitate manufacture,
It exhibits stable operation performance at all stages of its operation, operates with as little impact on the occupant as possible, and has the occupant's physique (for example, a person with a high or low sitting height, an adult or a child, etc.) Even if the riding position (for example, the position of clinging to the steering wheel) is different, the operation output of the gas generator can be arbitrarily determined so that the occupant can be safely restrained.
In addition, the gas generator is capable of adjusting the timing of increasing the output.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view showing one embodiment of a gas generator of the present invention.

FIG. 2 is a longitudinal sectional view showing another embodiment of the gas generator of the present invention.

FIG. 3 is a longitudinal sectional view showing another embodiment of the gas generator for an airbag of the present invention.

FIG. 4 is a longitudinal sectional view showing still another embodiment of the gas generator for an airbag of the present invention.

FIG. 5 is a longitudinal sectional view showing another embodiment of the gas generator of the present invention.

FIG. 6 is an exploded perspective view showing a partition.

FIG. 7 is a longitudinal sectional view showing still another embodiment of the gas generator for an airbag of the present invention.

FIG. 8 is a perspective plan view of the gas generator shown in FIG. 7;

FIG. 9 is an essential part cross-sectional view showing an opening.

FIG. 10 is an essential part perspective view showing a positioning structure of an igniter and a cable.

FIG. 11 is a sectional view of a principal part showing another embodiment of the coolant filter.

FIG. 12 is a longitudinal sectional view showing an embodiment in which an auto-ignition material is arranged.

FIG. 13 is a configuration diagram of an airbag device of the present invention.

FIG. 14 shows two flow paths in the configuration diagram of the airbag device of the present invention.

[Explanation of symbols]

 Reference Signs List 3 housing 5a first combustion chamber 5b second combustion chamber 7 partition 9a first gas generating agent 9b second gas generating agent 12a first igniter 12b second igniter 13 initiator color 22 coolant filter 26a First gas outlet 26b Second gas outlet 27 Seal tape 27a First seal tape 27b Second seal tape

Claims (10)

[Claims] 1. An outer shell containing two or more ignition means ignited by an impact, and two or more gas generation means each igniting and burning by the ignition means to generate a combustion gas for inflating an airbag. A plurality of gas outlets are formed in a housing forming a container, and the gas outlets start to burn first in an airbag gas generator closed by a shutoff means for maintaining the internal pressure of the housing to a constant pressure. The first combustion chamber and the second combustion chamber which starts burning later are separated by a wall having a communication hole, and the communication hole is provided with a fire prevention means, and the combustion in the first combustion chamber is performed. Thus, a gas generator for an airbag is characterized in that combustion in the second combustion chamber does not occur. 2. The fire prevention means is a shielding member.
A gas generator for an airbag as described in the above. 3. The gas generator for an airbag according to claim 2, wherein the shielding member shields the communication hole from the first combustion chamber side. 4. The sealing tape according to claim 1, wherein the fire prevention means is a seal tape which shields the communication hole from the first combustion chamber.
Or the gas generator for an airbag according to 3. 5. The fire prevention means is a shielding plate.
5. The gas generator for an airbag according to any one of 4). 6. The combustion chamber according to claim 1, wherein the first combustion chamber and the second combustion chamber are provided concentrically in the housing and adjacent to each other in the radial direction or the radial and axial directions. Gas generator for airbags. 7. An ignition means is connected to each of the first combustion chamber and the second combustion chamber.
The gas generator for an airbag according to any one of claims 1 to 6, wherein the gas generator is fixed to two initiator collars and attached to a housing. 8. The gas generator for an airbag according to claim 1, wherein the two ignition means are separated by one separation cylinder so that the flame does not propagate to each other. 9. The gas for an air bag according to claim 8, wherein the ignition means includes a transfer charge, and the separation cylinder is expanded in a radial direction by a pressure when the transfer charge is ignited and burns, so that the flames are not transmitted to each other. Generator. 10. The gas generator for an airbag according to claim 1, wherein output forms of gas generating means housed in the first combustion chamber and the second combustion chamber are different.