JPH10203296A - Gas generator for air bag and air bag device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent entering of moisture from an inflammation hole by exploding a part of a structure for mounting detonator by explosive combustion of the detonator stored/fixed within a recess and burning inflammation chemical by flame in which the detonator burns. SOLUTION: When a sensor 6 senses impact, a firing pin 18 in the sensor 6 is fired and a detonator 10 stored/fixed within a recess 17 of a detonator piece 11 is stuck, in a gas generator. When the detonator 10 is stuck with the firing pin 18, the detonator 10 explosively burns with the energy, explodes the bottom part of the detonator piece 11 sectioning an inflammation chemical storing chamber and a sensor storing chamber and makes both of the storing chambers be communicated. Flame in which this detonator burns ignits inflammation chemical stored within an inflammation chemical storing chamber and burns the chemical and the flame burns gas generation agent 13 by passing through a through hole 20 and generates gas. An aluminum tape 16 is stuck to the opening of the recess 17 storing the detonator 10 and moisture absorption of the detonator 10 from the direction of the sensor 6 is prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a gas generator for an airbag device used for reducing the impact on an occupant during a vehicle collision, and more particularly to a gas sensor for sensing an impact by a mechanical mechanism. The present invention relates to a structure of an igniting means for sensing an impact and burning a gas generating agent in an activated mechanical ignition type gas generator.

[0002]

2. Description of the Related Art Conventional gas generators include an electric ignition type and a mechanical ignition type. The electric ignition gas generator activates the igniter by igniting the electric power by the heat generated by the electric current, whereas the mechanical ignition gas generator activates the primer by piercing a firing pin emitted from a mechanical sensor. Is ignited, and the flame burns the transfer charge. Among them, a mechanical ignition type gas generator has an advantage that electric wiring and the like are not required and can be manufactured at low cost.

A general mechanical ignition type gas generator is internally fixed with an ignition means, that is, a mechanical sensor that detects an impact by a mechanical mechanism and fires a firing pin, and a detonator piece or the like, and pierces the firing pin. It contains a primer that ignites when struck, and a transfer charge that ignites with the flame of the primer and burns the gas generating agent.The primer piece has a transfer hole through which the flame of the primer is lit to ignite the charge. Has been drilled. This mechanical ignition type gas generator fires a firing pin when a mechanical sensor detects an impact, pierces the firing pin and ignites the detonator, and the flame burns the transfer charge through the fuse hole of the detonator piece. Then, the flame generated by the combustion of the transfer charge burns the gas generating agent to generate gas. The generated gas is cooled and purified while passing through the coolant and the filter, and flows into the airbag from the gas outlet.

[0004] The primer piece fixes the primer in the housing and defines a chamber for accommodating the sensor and a chamber for accommodating the explosive charge. The primer fixed with this primer piece is pierced by the firing pin fired from the sensor and ignited, burning the transfer charge, so that the primer piece receives the primer flame generated on the sensor side of the primer piece,
A heat transfer hole is provided to pass through a chamber in which the transfer charge is stored. And in the opening of this drilled fire hole,
In order to prevent moisture from entering through the fire hole, moisture-proof means such as attaching a seal tape is required.

[0005]

The detonator piece used in the conventional mechanical ignition type gas generator burns the detonator with the flame of the detonator, so that the flame of the detonator is transferred to a chamber containing the detonator. A heat transfer hole for passing the heat transfer hole is required, and the heat transfer hole is formed, and the chamber for storing the explosive charge and the chamber for storing the sensor communicate with each other, thereby opening the heat transfer hole for the purpose of moisture prevention. Since it is necessary to provide a damp-proofing means for the part, it has been an obstacle in efficiently manufacturing the gas generator.

Accordingly, the present invention solves the above-mentioned problems of the conventional gas generator for an air bag, and necessitates the formation of a heat transfer hole and the application of moisture-proof means to the heat transfer hole. It is an object of the present invention to provide a gas generator for an airbag, which is easy to manufacture.

[0007]

SUMMARY OF THE INVENTION A gas generator for an air bag according to the present invention is a mechanically ignited gas generator, in particular, which uses a detonator mounting structure such as a detonator piece having no blast hole. A gas generator for a bag, wherein a flame of a primer ignited by being pierced by a firing pin passes through a part of the primer mounting structure ruptured by the explosion of the primer and ignites a transfer charge. Is what you do.

That is, the present invention provides a mechanical ignition type gas generator operated by a mechanical sensor, a structure for mounting a primer which is disposed between the mechanical sensor and the transfer charge and defines each chamber for accommodating them. The body has a recess at the piercing point of the firing pin fired from the mechanical sensor, and is accommodated in the recess.
An airbag gas generator characterized in that a part of a structure for mounting a primer is ruptured by explosive combustion of a fixed primer, and a transfer charge is burned by a flame burned by the primer.

A mechanical sensor is a sensor that emits a firing pin by sensing an impact exclusively by a mechanical mechanism, such as stimulating the firing of a firing pin from the sensor with a weight that is moved by an impact. The generator is a gas generator for an airbag that generates a gas by detecting an impact by such a mechanical sensor. In this mechanical gas generator, basically, in a housing having a gas discharge port, an igniting means for generating a flame in conjunction with the detection of an impact, and burning by the flame from the igniting means, It contains a gas generating agent that generates gas, a coolant filter that cools and purifies the generated gas, and the like.

The ignition means in the gas generator according to the present invention comprises:
It includes a mechanical sensor that fires a firing pin by sensing an impact solely by a mechanical mechanism, a primer that is pierced by the firing pin and fires, and a transfer charge that is burned by the flame of the primer.

[0011] In the above-mentioned primer, for example, a chemical such as a chemical containing trisinate and the like which is ignited by the energy pierced by a firing pin is put into a container such as an aluminum can and the upper surface is covered with a lid of an aluminum plate. Either the mouth is deformed to fix the lid, or the agent is sandwiched between sheets and placed between the cap and the cup in a copper alloy cup having a through hole in the ceiling surface. In the present invention, it is also possible to directly press the above-mentioned medicine directly into the hollow without using a primer. When the drug is directly pressed into the cavity of the primer mounting structure, a step for manufacturing the primer by enclosing the drug in a container and a step of fixing the primer are not required, and
Once the drug is loaded, it can be reliably pierced with a firing pin and ignited without moving thereafter. Such a primer is accommodated and fixed in a recess formed in a primer mounting structure such as a primer piece.

The primer mounting structure is disposed between the explosive and the mechanical sensor, and defines a chamber for accommodating each of them. A place where a firing pin fired from the mechanical sensor pierces. Is formed with a recess for accommodating and fixing the primer. A part of the primer mounting structure was ruptured by the explosion of the primer contained in the cavity,
The chamber accommodating the explosive and the chamber accommodating the sensor communicate with
The transfer charge is burned by the flame of the detonator ignited by the firing pin. It is desirable that a part of the primer mounting structure that is ruptured by the explosion of the drug is a concave bottom surface. This primer mounting structure can be formed using, for example, aluminum, iron, stainless steel, or the like. This primer mounting structure has a thickness at the bottom surface of the recess of 0.05 to 1.5 mm when the structure is formed using aluminum, and 0.05 to 1.0 mm when formed using iron or stainless steel.
It is desirable to form them so that As a method of forming the thickness of the hollow bottom to such a thickness, a method of cutting a predetermined portion of the primer mounting structure with a predetermined thickness or a method of forming a through hole by drilling the structure. There is a method in which the opening is formed, one opening of the through hole is covered with a plate having a predetermined thickness, and the plate is bonded to a primer mounting structure by bonding or welding.

The size of the recess formed in the primer mounting structure is such that it can rupture a part of the primer fixing structure and accommodate and fix a primer containing an amount of chemical required for combustion of the transfer charge. In the case where a tricinate-based drug is used as the drug in the primer, the depression has a size capable of accommodating a drug of, for example, 50 to 300 mg, or an inner diameter of 2.5 to 6 mm and a depth of 2 mm.
It can be a substantially cylindrical hole having a size of about 5 mm.
The primer mounting structure may be formed separately from the housing as a substantially flat-shaped primer piece having a hollow at the piercing point of the firing pin, and may be formed integrally with a diffuser shell or a closure shell constituting the housing. Can also.

[0014] A gap may be formed around the cavity to secure a predetermined space between the cavity opening surface and the sensor. Due to the formation of the gap, the inner wall has a stepped shape in which the inner diameter is narrowed at the back by the recess and the gap.

In the gas generator according to the present invention, the opening of the cavity containing the primer is covered with a thin plate and the interior of the cavity is closed in order to prevent the primer from absorbing moisture due to the ingress of moisture from the opening direction of the cavity. You may. As a thin plate used for the purpose of this moisture proof, an aluminum tape having a thickness of 20 to 50 μm is desirable. In order to protect the primer from moisture, an O-ring or the like may be further applied between the mechanical sensor and the primer mounting structure for sealing. If the detonator absorbs moisture, it may not ignite even if it is pierced by a firing pin. Therefore, it is desirable to prevent moisture from entering from the direction of the cavity opening.

The housing is formed by casting or pressing a diffuser shell having a gas outlet and a closure shell having a sensor accommodating port, and joining them by various welding methods such as beam welding and friction welding. Is done.

As the gas generating agent, known gas generating agents such as an azide-based gas generating agent and a non-azide-based gas generating agent can be used. Examples of the azide-based gas generating agent include those based on inorganic azides, particularly sodium azide (sodium azide), which have been widely used in the past, such as an equivalent mixture of sodium azide and copper oxide. As the main component, a nitrogen-containing organic compound such as tetrazole, triazole, or a metal salt thereof and an oxygen-containing oxidizing agent such as an alkali metal nitrate, triaminoguanidine nitrate, carbohydrazide, nitroguanidine, etc. There is a composition using a nitrogen source and an alkali metal or alkaline earth metal nitrate, chlorate, perchlorate or the like as an oxidizing agent. Considering safety and the like, non-azide gas generating agents are advantageous.

The coolant / filter has a function of removing combustion residues generated by combustion of the gas generating agent and cooling the combustion gas. For example, stainless steel, SUS304, SUS310S, SUS316
(JIS standard symbols) can be used. In addition, as for the filter coolant, a combination of a filter and a coolant that have been widely used in the past can be used.

The gas generator of the present invention fires a firing pin when the sensor detects an impact, pierces the primer contained and fixed in the cavity of the primer mounting structure, and ignites. The ignited detonator explosively burns to explode a part of the structure for mounting the detonator, and ignites and burns the transfer charge by the flame. The flame of the transfer charge ignites and burns the gas generating agent to generate gas. The generated gas is cooled and purified by a coolant filter, and is injected into the airbag from a gas outlet of the housing.

Further, the above-described gas generator for an air bag can be formed as an air bag device by combining an air bag which expands by introducing gas generated by the gas generator and a module case which houses the air bag. This airbag device is housed and fixed in an appropriate place in a vehicle such as a steering wheel or a dashboard.

[0021]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a longitudinal sectional view of a gas generator according to an embodiment of the present invention, FIG. 2 is an enlarged longitudinal sectional view of a main part showing an ignition means of the gas generator of the present invention, and FIG. And FIG. 4 is a configuration diagram of an airbag device.

The mechanical ignition type gas generator having a built-in mechanical sensor shown in FIG. 1 is obtained by joining a diffuser shell 2 having a gas outlet 4 and a closure shell 3 having a sensor accommodating port 7 by friction welding. A housing 1 is formed. The interior of the housing 1 is defined by a partition wall into two chambers, an ignition means storage chamber 8 and a combustion chamber 9, and the ignition means storage chamber is further divided into two sections by a primer piece 11, a charge transfer chamber and a sensor storage chamber. The room is defined. The combustion chamber 9 contains a non-azide gas generating agent 13, a coolant 14 and a filter 15, which surround the gas generating agent and are made of an annular wire mesh laminate made of stainless steel. Inside, the priming device 10 housed and fixed in the recess 17 of the priming piece 11 and the ignition means composed of the transfer charge 12 and the sensor 6 arranged vertically above and below the priming piece 11 are accommodated. . In the ignition means accommodating chamber, the explosive charge 12 is accommodated in the explosive charge accommodating chamber, and the mechanical sensor 6 is accommodated in the sensor accommodating chamber. In FIG. 1, 19 indicates a safety device, and 21 indicates a combustion ring. In the gas generator shown in this embodiment, when the sensor 6 detects an impact, a firing pin 18 in the sensor is fired,
The primer 10 housed and fixed in the recess 17 of the primer piece 11 is pierced. When the primer 10 is pierced by the firing pin 18,
It burns explosively with the energy, ruptures the bottom of the primer piece 11 defining the transfer charge storage chamber and the sensor storage chamber, and connects both storage chambers. The flame burned by this primer ignites and burns the explosive stored in the explosive storage chamber,
The flame burns the gas generating agent 13 through the through hole 20 to generate gas. The generated gas is coolant 14
After being cooled by the filter 15, it is purified by the filter 15 and discharged from the gas discharge port 4. This coolant 14 and filter 15
As a filter, a wire mesh formed by compression molding as an annular laminated body to form a coolant filter may be used.

FIG. 2 is a longitudinal sectional view of a main part showing an ignition means according to the present invention. The ignition means comprises a sensor 6, a primer 10 and a transfer charge 12. In the mechanical ignition type gas generator shown in this embodiment, the primer piece 11 is formed as a separate body from the housing 1 and is disposed in the ignition means accommodating chamber 8 so that the transfer charge accommodating chamber, the sensor accommodating chamber and Is defined. A depression 17 is formed in the primer piece 11, and the primer 10 is accommodated and fixed in the depression 17. Around the recess 17 is formed a gap 5 having an inner diameter larger than that of the recess 17.

The primer piece 11 is a substantially plate-like member made of aluminum having a thickness of about 5 to 8 mm. The recess 17 for accommodating and fixing the primer 10 has a firing pin 18 pierced from a sensor of the primer piece. It is formed at the protruding point. In the recess 17, a primer 10 containing 50 to 300 mg of a powdery tricinate drug is housed and fixed.
As shown in FIG. 3, the primer piece 11 is pierced by the firing pin 18, ignited, exploded by the explosively burning primer 10, and connects the transfer charge accommodating chamber and the sensor accommodating chamber. Before the transfer, the charge storage chamber and the sensor storage chamber are surely defined by the primer piece 11. An aluminum tape 16 is adhered to the opening of the recess 17 containing the primer 10 so that the primer 10 can be seen from the sensor direction.
To prevent moisture absorption.

Indentation 17 provided in primer piece 11
Is formed in such a size that it can contain an amount of the medicine 10 necessary for igniting the transfer charge 12, and in this embodiment, the detonator piece is made of aluminum and has a thickness of about 5 to 8 mm. Since the primer is a substantially flat member, and the primer is formed using a tricinate-based chemical, the depression formed in the primer piece is a substantially cylindrical hole having an inner diameter of 2.5 to 6 mm and a depth of 2 to 5 mm. The thickness of the primer piece on the bottom surface is regulated to 0.3 to 1.5 mm.

The mechanical sensor 6 contains a weight (not shown) that moves due to acceleration at the time of collision and a firing pin 18 fired by a spring, and has a safety device 19 on its bottom surface. .

FIG. 4 is a diagram showing the construction of an airbag device. The gas generator of the present invention and an airbag (bag) 100 are shown.
And a module case 101. The gas discharged from the gas discharge port 4 of the gas generator is
00, the airbag 100 breaks the module cover 102 and bulges out, forming a cushion between the steering wheel 103 and the occupant for absorbing impact.

As the gas generator, the gas generator described with reference to FIGS. 1 and 2 is used.

The module case 101 is made of, for example, polyurethane and includes a module cover 102. In this module case 101, the airbag 10
0 and a gas generator are housed in the pad module, and are mounted on the vehicle side such as the steering wheel 103 of the vehicle.

The airbag 100 is formed of nylon (eg, nylon 66), polyester, or the like.
The bag mouth surrounds the gas outlet 4 of the gas generator, and is fixed to a flange portion of the gas generator in a folded state.

[0032]

As described above, the present invention is constructed as described above. Therefore, in the production of a gas generator, a blast hole is conventionally required in a detonator piece, This eliminates the need to apply moisture proof means, is easy to manufacture, and reliably defines a chamber for accommodating explosives and a chamber for accommodating sensors to completely transfer moisture between the two chambers. A blocked gas generator for an airbag can be provided.

[Brief description of the drawings]

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

FIG. 2 is an enlarged longitudinal sectional view of a main part showing an ignition means of the gas generator of the present invention.

FIG. 3 is an enlarged vertical sectional view of a main part showing a rupture state of a primer piece;

FIG. 4 is a configuration diagram of an airbag device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Housing 2 Diffuser shell 3 Closure shell 6 Mechanical sensor 10 Detonator 11 Detonator piece 12 Primer 13 Gas generating agent 17 Depression 18 Shooting pin

Claims (13)

[Claims] In a mechanically ignited gas generator operated by a mechanical sensor, a primer mounting structure disposed between the mechanical sensor and a transfer charge and defining each chamber for accommodating the same is provided. It has a recess at the piercing point of the firing pin fired from the mechanical sensor, and explosive combustion of the primer contained and fixed in the recess causes a part of the primer mounting structure to rupture, A gas generator for an air bag, characterized in that a transfer charge is burned by the flame burned by the primer. 2. The gas generator for an air bag according to claim 1, wherein a part of the primer mounting structure that bursts due to explosive combustion of the chemical is a concave bottom surface. 3. The size of the recess is such that a part of the primer mounting structure is ruptured, and further, a primer containing an amount of chemical required for burning the transfer charge can be accommodated and fixed. The gas generator for an airbag according to claim 1 or 2, wherein 4. The amount of the chemical required to rupture a part of the structure for mounting a primer and to further burn the transfer charge is 50 to 30.
4. The gas generator for an airbag according to claim 3, wherein the amount is 0 mg. 5. The hollow has an inner diameter of 2.5 to 6 mm and a depth of 2 to 6.
The gas generator for an air bag according to any one of claims 1 to 4, wherein the gas generator is a substantially cylindrical hole having a size of 5 mm. 6. The gas generator for an airbag according to claim 1, wherein the chemical contained in the primer is a chemical containing a powdery tricinate or the like. 7. The squib mounting structure is made of aluminum,
It is made of iron or stainless steel, and the thickness of the primer mounting structure at the bottom of the recess is 0.05 to 1.5 mm for a aluminum mounting structure made of aluminum or 0.05 to 1.0 mm for a primer mounting structure made of iron or stainless steel. The gas generator for an airbag according to any one of claims 1 to 6, wherein: 8. The gas generator for an air bag according to claim 7, wherein the primer mounting structure is made of aluminum. 9. The airbag according to claim 1, wherein the primer mounting structure is a substantially flat-shaped primer piece having a depression formed at a piercing point of a firing pin. For gas generator. 10. The gas generation for an air bag according to claim 1, wherein the primer mounting structure is formed integrally with a diffuser shell or a closure shell constituting a housing. vessel. 11. The gas for an airbag according to claim 1, wherein the opening of the cavity accommodating and fixing the primer is covered with a thin plate to close the interior of the cavity. Generator. 12. The gas generator for an air bag according to claim 11, wherein said thin plate is an aluminum tape having a thickness of 20 to 50 μm. 13. A gas generator for an airbag that generates a gas by sensing an impact, an airbag that expands by introducing a gas generated by the gas generator, and a module case that houses the airbag. Including
An airbag device, wherein the gas generator for an airbag is the gas generator for an airbag according to any one of claims 1 to 12.