JP2001151071A - Gas generator for air bag, and air bag device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a gas generator that can simply and reliably close gas emission openings formed in its housing. SOLUTION: The gas generator for an air bag houses ignition means operated on impact and gas generating means ignited and combusted by the ignition means in a housing with a plurality of gas emission openings in the peripheral wall. The gas emission openings are arranged in rows along the axis of the housing. Every two to six rows of the gas emission openings adjoining along the circumference of the housing forms one group, All the groups of the gas emission openings are arranged at given intervals along the circumference of the housing.

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 suitably used for an inflatable safety system of a motor vehicle, and more particularly, to an arrangement and a shape of a gas outlet.
The present invention relates to a gas generator for an airbag characterized by the sealing method and an airbag device using the same.

[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.

Accordingly, in a gas generator used in an airbag system, a gas outlet for discharging gas to the airbag is formed in an outer shell (housing). Usually, the gas outlet formed in the housing is closed with a metal sealing tape because of the need for rust prevention of the internal metal member housed in the housing and, in some cases, the need to prevent moisture such as a gas generating agent. ing.

Conventionally provided gas generators, such as gas generators for a driver's seat, a passenger's seat, or a side collision, have a housing having an overall size and the like depending on an arrangement place (or application). Although different, most of them use a cylindrical housing, and gas outlets are formed in a circumferential direction on a peripheral wall of the cylindrical housing. The gas outlet formed in the cylindrical surface is closed by a sealing tape attached in the circumferential direction, and the sealing tape is attached from inside the housing. Therefore, it is difficult to close the gas outlet with the seal tape. Particularly, when the housing has a long shape in the axial direction, the gas outlet formed in the peripheral wall is closed by the seal tape unless some measure is taken. It is difficult to do.

[0005] Further, the blockage of the gas discharge port is important for ensuring the operation reliability of the gas generator, and the outside air must not leak into the housing.

However, there has not been provided a gas generator which can easily and surely close the gas outlet.

[0007]

SUMMARY OF THE INVENTION Accordingly, the present invention solves the above-mentioned conventional problems, and provides a gas generator capable of easily and reliably closing a gas outlet formed in a housing.

[0008]

The gas generator of the present invention comprises:
It is characterized in that a plurality of gas outlets provided on the peripheral wall of the housing are arranged in series along the axial direction of the housing. If the gas outlet is formed in this way, the sealing tape can be stuck in the axial direction, so that the gas outlet is easily and reliably closed.

That is, the gas generator for an air bag according to the present invention comprises:
What is claimed is: 1. A gas generator for an airbag, comprising: a housing having a plurality of gas outlets on a peripheral wall; and an ignition means operated by an impact, and gas generation means ignited and burned by the ignition means. The outlets are arranged in the axial direction of the housing to form a row of gas outlets, and the row of gas outlets is arranged close to two to six rows in the circumferential direction of the housing to form a group of gas outlets. The gas outlet groups are arranged at predetermined intervals in the circumferential direction of the housing. The gas outlet row can be configured by, for example, arranging a plurality of gas outlets in series in the axial direction of the housing.

The gas outlet group is preferably adjusted so that the central angle between the gas outlets adjacent to each other in the circumferential direction of the housing is within a range of 10 ° to 30 °. In addition, it is desirable to form them at intervals of a central angle of 60 to 120 °. In addition, the gas discharge port row constituting the gas discharge port group may have a different gas discharge port inner diameter for each gas discharge port row. For example, a row of gas outlets consisting of gas outlets with a large inner diameter and a row of gas outlets consisting of gas outlets with a small inner diameter can be provided alternately in the circumferential direction of the housing.

The gas outlet group consisting of a plurality of gas outlet rows can be closed by a single seal tape for each gas outlet group. This makes it easier to close the gas outlet. In this case, the width of the gas outlet group closed by one seal tape is 2 to 20 mm, more preferably 2 to 20 mm, than the width of the seal tape.
It is desirable that the adjustment be made even smaller by 10 mm.
This is to ensure that the gas outlet is more reliably blocked.

In the present invention, a plurality of gas discharge ports are arranged in the axial direction of the housing without forming a group of gas discharge ports by arranging the gas discharge port rows in the vicinity of two to six rows in the circumferential direction of the housing. The gas outlet rows arranged in a line can be arranged at predetermined intervals in the circumferential direction of the housing. Also in this gas generator, the gas outlet is arranged in the axial direction of the housing.

That is, a gas generator for an air bag in which a housing having a plurality of gas outlets on a peripheral wall contains an ignition means operated by impact and gas generation means ignited and burned by the ignition means. Wherein the gas outlets are arranged in the axial direction of the housing to form a gas outlet row, and the gas outlet rows are arranged at predetermined intervals in the circumferential direction of the housing. It is a gas generator for airbags characterized by the following. The gas outlets arranged in the axial direction of the housing can be arranged in series in the axial direction of the housing, and the gas outlets (gas exhaust port row) are formed by sealing the sealing tape in a straight line along the axial direction of the housing. It can be closed by attaching it to For example, the closing of the gas outlet rows can be performed by a single piece of sealing tape attached to each row.

The gas generator having the gas outlets arranged as described above can be implemented in a gas generator having a housing which is short in the axial direction (for example, a gas generator for a driver's seat). In a gas generator using a housing that is longer in the axial direction than in the direction (for example, a gas generator for a passenger seat), a more remarkable effect can be exhibited.

For example, a housing is provided which is longer in the axial direction than in the radial direction. In this housing, a combustion chamber for housing the gas generating means and a filter means housing chamber for housing the filter means are provided in the axial direction of the housing. This is the case of a gas generator formed adjacently. In this case, the gas outlet is
In the peripheral wall of the housing, the inner side will be formed in a range to be a filter means accommodation chamber, but if it is formed as a gas outlet row or a group of gas outlets along the axial direction of the housing,
The sealing tape can be easily and reliably closed. Further, in a gas generator which is longer in the axial direction than in the radial direction and has a gas discharge port near the center thereof, further effects can be obtained by the present invention. For example, such an axially long housing,
This is the case of a gas generator in which combustion chambers are formed at both ends in the axial direction inside thereof, and a filter means accommodating chamber is formed between both combustion chambers (that is, the center of the housing). In such a gas generator, the gas outlet is formed near the center of the housing. However, if the gas outlets are arranged as in the present invention, the gas outlet can be easily and reliably closed.

In the present invention, metal foils formed of various metals can be used as the sealing tape, and these metal foils are formed in a belt shape and adhered in the housing with an adhesive or an adhesive. As the metal foil, an aluminum foil is preferable, and the aluminum foil is particularly preferably formed in a thickness of 50 to 160 μm.

In the housing provided with the gas discharge port as described above, the ignition means operated by the operation signal and the gas generation means for generating the working gas for inflating the airbag by the ignition means are housed. When the working gas has a high temperature and contains combustion products, a coolant and / or filter means formed by using a laminated metal mesh, expanded metal, or the like can be provided as necessary. Furthermore, members and structures necessary for the structure of the gas generator and members and structures advantageous for operation can be appropriately adopted.

As a gas generating means for generating a working gas by burning, in addition to an azide-based gas generating agent based on an inorganic azide, for example, sodium azide (sodium azide), which has been widely used in the past, an inorganic azide-based No non-azide gas generants can be used. However, in consideration of safety, a non-azide gas generating agent is desirable.

The above-described gas generator for an air bag is housed in a module case together with an air bag (bag body) that introduces and inflates the gas generated by the gas generator 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.

[0020]

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 showing a first embodiment of a gas generator for an airbag of the present invention.

In this gas generator, a cylindrical diffuser shell 1 having a gas discharge port 4 and a closure shell 2 for closing an end opening of the diffuser shell 1 are joined and integrated to form a housing 3. I have. A plurality of gas outlets are formed in a peripheral wall of the cylindrical housing, and the gas outlets are arranged along the axial direction of the housing as described later. In the housing 3, combustion chambers 6 each containing a gas generating agent 5 as gas generating means are formed at both ends in the axial direction (that is, on the closure shell side), and between the combustion chambers 6, that is, Near the center of the housing 3, a filter means accommodating chamber 8 for accommodating the cylindrical filter means 7 is provided. In the present embodiment, for the sake of explanation, the combustion chamber on the right side of the drawing is the first combustion chamber 6a, and the combustion chamber on the left side of the drawing is the second combustion chamber.
6b. The first combustion chamber 6a is in communication with the filter means accommodation chamber 8.

As shown in FIG. 2, the diffuser shell 1 is formed using a cylindrical straight tube, and a plurality of gas outlets 4 are provided on the peripheral wall in the area where the filter means accommodating chamber 8 is provided. Are arranged on a straight line in the axial direction to form a gas outlet row 50. The gas outlet rows 50 are arranged close to each other in two to six rows, and form a gas outlet group 60. In this embodiment, the gas outlet group 60
Is formed by arranging three gas outlet rows 50 in close proximity. The gas outlet group 60 is formed at a predetermined interval (preferably a central angle of 60 to 120 °) in the circumferential direction of the housing 3, and is formed at an interval of 90 ° in the present embodiment. . In the drawing, the arrangement interval of the gas outlet groups is represented by the inner angle θ between the gas outlet groups adjacent in the circumferential direction. In addition, in this gas outlet group 60,
It is desirable that the gas outlets 4 adjacent in the circumferential direction be adjusted so that the central angle φ is in the range of 10 to 30 °. Further, in the present embodiment, the gas outlet rows 50 constituting each gas outlet group 60 are formed of the gas outlets 4 having different inner diameters. It is also possible to form the gas outlet group 60 by arranging only the configured gas outlet rows 50 in the vicinity of two to six rows. Regarding the arrangement of the gas outlets, as shown in the sectional view along the length direction of FIG.
4 can be arranged in the axial direction of the housing to form a gas outlet row 50, and the gas outlet rows 50 can be arranged close to six rows in the circumferential direction of the housing to form a gas outlet group 60. As shown in a cross-sectional view perpendicular to the length direction of FIG. 3B, the gas outlet groups 60 can be arranged in four groups at a central angle (θ) of 90 ° in the circumferential direction of the housing. This figure 3
In the example shown in a and b, two gas outlet rows 50 at the center of the six gas outlet rows 50 constituting the gas outlet group 60 are formed by the gas outlets 4 having a large inner diameter, The two gas outlet rows 50 arranged on both sides thereof are formed by the gas outlets 4 having a small inner diameter.

Further, as shown in FIG. 4, the gas outlet rows 50 may be arranged independently in the circumferential direction without forming a group of gas outlets adjacent to each other in two to six rows. in this case,
The gas outlet rows are arranged at predetermined intervals in the circumferential direction of the housing. The gas outlet 4 has a function of adjusting the internal pressure of the housing 3 when the gas generating agent 5 burns, and the total area of the opening is equal to the gas generating agent 5 accommodated in each combustion chamber 6. It is determined based on the characteristics and the like.

The gas outlet 4 is closed with a sealing tape 9 made of aluminum for the purpose of preventing moisture. In the present invention, the gas outlet 4 is formed as a row of gas outlets or a group of gas outlets. Since the gas discharge ports 4 are arranged linearly along the axial direction, the gas discharge ports 4 can be closed by the seal tape 9 extending in a belt shape along the axial direction of the housing 3. That is, since it is not necessary to attach the seal tape 9 in the circumferential direction of the housing, the attachment becomes easy. The sealing tape that closes the gas outlet is more than the gas outlet row 50 or the gas outlet group 60,
Preferably, it is formed to be 20 mm wide.

The closure shell 2 comprises an annular portion 21 connected to the opening end of the diffuser shell 1 and a tubular portion 22 integrally connected to the central opening of the annular portion. The cylindrical portion 22 protrudes outward in the axial direction of the housing 3 and houses an ignition means 26 in its internal space. In the present embodiment, the first closure shell 2a that closes the end opening on the first combustion chamber 6a side has a cylindrical portion 22a and an annular portion 21a that is connected to an end of the cylindrical portion 22a in a flange shape. The second closure shell 2b for closing the end opening on the second combustion chamber 6b side has a cylindrical portion 22b and an annular portion orthogonal to the peripheral wall of the cylindrical portion 22b in a flange shape. 21a. Each tubular part 2 of the first and second closure shells 2a, 2b
The first ignition means 26a and the second ignition means 26b are accommodated in 2a and 22b, respectively.
An igniter 10 housed in 1 and ignited by the igniter 10
It is composed of a transfer charge 12 to be burned. The cylindrical portion 22a of the first closure shell 2a is closed by a cap member 14 connected to the end of the heat transfer tube 13, and the cylindrical portion 22b of the second closure shell 2b is connected to the second combustion chamber. The 6b side is closed by a porous disc-shaped lid member 16 having a plurality of heat transfer holes 15b. Fire tube 13 connected to cap member 14
Has a plurality of heat transfer holes 15a formed in its peripheral wall, and its internal space communicates with the inside of the cylindrical portion 22a of the first closure shell 2a.

In the present embodiment, the periphery of the annular portion 21b forming the second closure shell 2b is formed so as to protrude outward in the radial direction of the diffuser shell 1. Thus, the annular portion 21b can function as a flange when this gas generator is mounted on a module. Also, the cylindrical portion of the first closure shell 2a
A thread groove (for example, the diameter of the cylindrical portion 22a is 22 mm)
, A thread groove having a pitch of 1.0 mm) is formed. As a result, if a nut is combined with the cylindrical portion 22a, it can function as a stud bolt when attaching the gas generator to the module case.

The first combustion chamber 6a formed on the right side of the housing 3 in the drawing is partitioned from the filter means accommodating chamber 8 by a partition member. In the present embodiment, a baffle member 17 that is convexly curved toward the first ignition means 26a is used as the partition member. The baffle member 17 has a function of preventing the gas generating agent 5a from moving to the filter means accommodating chamber 8. However, the baffle member 17 is formed with a plurality of through holes 18a that communicate the first combustion chamber 6a and the filter housing chamber 8. The through hole 18a is opened without being closed by a seal tape or the like, and the first combustion chamber 6a and the filter means accommodating chamber 8 are always in communication. This allows the first combustion chamber
Moistureproofing of the gas generating agent 5a contained in 6a and rustproofing of internal metal members can be achieved only by sealing the plurality of gas outlets 4 formed on the peripheral wall of the cylindrical housing 3, simplifying the sealing mechanism. can do. The through hole 18a formed in the baffle member may be appropriately closed with a sealing tape or the like, and the sealing tape may be formed so as to be ruptured by the combustion of the gas generating agent so that the two chambers communicate with each other. In the first combustion chamber 6a, a perforated cylindrical first gas generating agent 5a is accommodated, and this gas generating agent 5a is an inward flange-shaped plate through which a heat transfer tube 13 passes through a central opening. It is supported by a member 23. This plate member 23
The peripheral wall portion 19 is fitted inside the combustion chamber 6a, and the flange portion 20 connected to the peripheral wall portion 19 supports the gas generating agent 5a. Thereby, the movement of the gas generating agent 5a is prevented, and it is possible to avoid a situation where the gas generating agent 5a is damaged by vibration or the like. Further, since the plate member 23 is fitted inside the housing 3 so as to be slidable in the axial direction of the housing 3, even when the capacity of the gas generating agent 5a is changed, the gas generating agent 5a is reliably supported and supported. It can be pressed and / or held.

The gas generating agent 5a accommodated in the combustion chamber 6a is supported by the plate member 23, and the flame of the ignition means 26a is surely blown into the combustion chamber 6a by the transmission tube 13, so that the combustion chamber 6a Even when the amount of the gas generating agent 5a stored therein changes, the gas generating agent 5a is reliably ignited and burned.

The baffle member 17 having the through hole 18a supports the gas generating agent 5a housed in the first combustion chamber 6a and prevents the gas generating agent 5a from moving into the filter means housing chamber 8. Further, the baffle member 17 does not have a function of adjusting the internal combustion pressure in the first combustion chamber 6a. Therefore, the through hole 18a is adjusted so that the inner diameter is smaller than the first gas generating agent 5a, and the total area of the opening is larger than the total area of the opening of the gas outlet 4.

The second combustion chamber 6b formed on the left side of the housing 3 in the drawing is formed inside a cup member 24 having a plurality of through holes 18b formed in a peripheral wall. Is closed by a closing member 25 formed using a stainless steel foil having a thickness of about 40 μm. The closing member 25 can be adhered by, for example, an adhesive or an adhesive. This through hole 18b can be formed in the bottom of the cup member 24 (that is, on the filter means housing chamber 8 side), but in order to prevent direct injection of flame and gas generated in the first combustion chamber 6a. Is preferably formed on the peripheral wall portion 33 as in this embodiment. As shown in the present embodiment, when the through hole 18b is formed in the peripheral wall portion 33 of the cup member 24, the through hole is provided between the outer peripheral surface of the cup member 24 and the inner peripheral surface of the housing 3. Channel 27 leading from 18b to filter means storage chamber 8
To form For example, as shown in the present embodiment, the flow path 27 between the inner peripheral surface of the housing and the outer peripheral surface of the cup member 24 increases the outer diameter of the cup member 24 from the portion where the through-hole 18b is formed to the filter means housing chamber. Small on the 8 side, housing 3
It can be formed by securing a space 27 between the inner peripheral surface and the outer peripheral surface of the cup member 24. This second combustion chamber 6b
Contains a single-hole cylindrical first gas generating agent 5b, and is supported by a plate member 23 housed in the second combustion chamber 6b, like the first gas generating agent 5a.

In the present embodiment, a gas generating agent having a different shape from the first gas generating agent 5a and the second gas generating agent 5b is used. Of course, it is possible to use the same gas generating agent for both combustion chambers 6a, b, but as shown in the present embodiment, if the shape of the gas generating agent differs for each combustion chamber,
The operation performance of the gas generator (that is, the deployment pattern of the airbag) can be variously adjusted. In addition, as in the present embodiment, if each combustion chamber 6a, b contains a gas generating agent having at least one or more different combustion speed, composition, composition ratio, and amount even if they have the same shape, the The operating performance of the generator can be ambiguously adjusted.

The filter means housing chamber 8 houses a cylindrical filter means 7. In the present embodiment, one formed by winding expanded metal in multiple layers is used. Other filter means
7 is formed by using a laminated wire mesh, and has a cooling effect that has both the cooling effect of combustion gas and the function of collecting combustion residue.
It is also possible to use filters. The filter means 7 is supported and fixed by a filter means support member 28, and a gap 32 having a predetermined width is secured between the outer peripheral surface and the inner peripheral surface of the housing 3. In the present embodiment, the filter means support member 28 has an inner peripheral wall 29 which is fitted inside the central opening of the filter means 7, and extends on the opposite side to the inner peripheral wall 29 and is fitted inside the housing inner peripheral surface. Outer peripheral wall 30 and an annular portion 31 connecting the inner peripheral wall 29 and the outer peripheral wall 30, and the filter means 7 is provided between the filter means support members 28 fitted inside the housing 3. The inner peripheral surface is supported and fixed by the filter means support member 28. In addition, the gap 32 secured between the outer peripheral surface of the filter means 7 and the inner peripheral surface of the housing 3 functions as a gas flow path, and when the combustion gas passes through the filter means 7, it concentrates near the gas outlet 4. Avoid the situation that you do. In the present embodiment, the filter means support member 28 provided on the first combustion chamber 6a side is supported and fixed by an embossed structure or a press fit provided on the housing 3 on the outer peripheral surface.

The operation pattern of the gas generator shown in FIG.

First, when the first ignition means 26a operates,
The flame passes through the transfer tube 13 and blows out from the transfer hole 15a into the first combustion chamber 6a. This flame is the first gas generating agent
5a is ignited and burned to generate combustion gas. The working gas generated by the combustion of the first gas generating agent 5a passes through the through hole 18a of the baffle member 17 and reaches the filter means accommodating chamber 8 as it is. Then, while passing through the filter means 7, it is purified and cooled and flows into the gap 32, and the sealing tape
It breaks 9 and is discharged from gas outlet 4. The second gas generating agent 5b accommodated in the second combustion chamber 6b, due to the through-hole 18b of the cup member 24 being closed by the rupture member, depends on the combustion of the first gas generating agent 5a. It does not ignite or burn with the generated gas. The second gas generating agent 5b is ignited and burned by the operation of the second ignition means 26b. However, when an auto-ignition material (AIM) that ignites and burns by the heat of combustion (conduction heat) of the first gas generating agent 5a transmitted from the housing 3 or the like is disposed in the second combustion chamber 6b, It is possible to ignite and burn by the combustion of the auto-ignition material.
As such an auto-ignition material, for example, nitrocellulose or the like can be used, and is usually arranged so as to ignite and burn with a delay of 100 ms or more after the first ignition means 26a operates.

The second ignition means 26b is provided with a first ignition means 26a.
Or at a predetermined interval after the operation of the first ignition means 26a. As a result, the ignition timing of the two ignition means 26a, b is adjusted, that is, the first ignition means 26a
The output form (operating performance) of the gas generator is arbitrarily adjusted depending on whether the second ignition means 26b is operated after the operation of or the first ignition means 26a and the second ignition means 26b are simultaneously operated. 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.

When the second ignition means 26b operates, the flame is blown out from the heat transfer hole 15b of the lid member 16 into the second combustion chamber 6b, and the second gas generating agent 5b is ignited and burned. Generate gas. The working gas is released from the through-hole 18b of the cup member 24 by peeling off the closing member 25, and
It reaches the filter means accommodating chamber 8 through a flow path 27 provided between the housings. Thereafter, similarly to the combustion gas generated from the first gas generating agent 5a, the gas passes through the filter means 7 and is discharged from the gas discharge port 4. Embodiment 2 FIG.
FIG. 5 is a longitudinal sectional view showing another embodiment of the gas generator for an airbag of the present invention.

In this gas generator, a cylindrical diffuser shell 1 having a gas discharge port 4 and a closure shell 40 for closing an end opening of the diffuser shell 1 are connected similarly to the gas generator shown in FIG. Integrated into the housing
3 are formed. However, the location of the filter means accommodating chamber 8 is different, and the filter means accommodating chamber 8 is formed so as to be partitioned at the end of the housing 3. Since one combustion chamber 6 containing the gas generating agent 5 is defined at the other end of the housing 3, in the present embodiment, the combustion chamber 6, the filter means accommodation chamber 8, Are provided adjacent to each other in the axial direction.

A combustion chamber 6 formed at one end of the housing 3
Is partitioned from the filter means accommodating chamber 8 by a partition member. As this partition member, a baffle member 17 which is convexly curved toward the combustion chamber 6 is used as in the first embodiment. The baffle member 17 has a plurality of through-holes 18 communicating the combustion chamber 6 and the filter housing chamber 8, and the two chambers 6, 8 are always in communication. Since the moisture prevention of the gas generating agent 5 contained in the combustion chamber 6 and the rust prevention of the internal metal member are performed by the seals of the plurality of gas outlets 4 formed on the peripheral wall of the cylindrical housing 3, The sealing mechanism on the combustion chamber 6 side is simplified. Of course, also in this embodiment, when simplification of the sealing mechanism is not required, the through-hole 18 can be closed with a sealing tape that is ruptured by the combustion of the gas generating agent.

The combustion chamber 6 contains a gas generating agent 5 in the form of a porous cylinder. The gas generating agent 5 is supported between an inward flange-shaped plate member 23 and a baffle member 17. I have. As a result, the movement of the gas generating agent 5 is prevented, and a situation in which the gas generating agent 5 is damaged by vibration or the like can be avoided. Since the plate member 23 can slide in the axial direction of the housing 3, the movement of the gas generating agent 5 can be reliably prevented even when the capacity of the gas generating agent 5 changes. .

Also in the present embodiment, the diffuser shell 1 constituting a part of the housing 3 is formed using a cylindrical straight tube, and the peripheral wall of the area where the filter means accommodating chamber 8 is provided is A plurality of gas outlets 4 are provided. As in the first embodiment, the gas outlets 4 are linearly arranged along the axial direction of the housing 3, and the gas outlet row 50 or the gas outlet row
A group of gas outlets 60 in which two to six rows of 50 are arranged are formed.

As in the first embodiment, the gas outlet 4 is closed with a band-shaped sealing tape 9 extending linearly along the axial direction of the housing 3. Moisture proofing is in place. Also in the present embodiment, since the seal tape 9 can be linearly stuck along the axial direction of the housing 3, the gas outlet 4 can be simply and reliably closed.

The closure shell 40a for closing the opening of the diffuser shell 1 on the side of the filter means accommodating chamber 8 projects from the annular part 41a connected to the opening edge of the diffuser shell 1 to the filter means accommodating chamber 8 side. Circular part 42
And a screw portion 43 protruding outward from the annular portion 41a in the axial direction of the housing 3. The circular portion 42 is adjusted to a size that can contact the inner peripheral surface of the filter means 7,
It serves to support the filter means 7. By combining a nut (not shown) with the screw portion 43, the gas generator can be attached to the module case.

On the other hand, the closure shell 40b for closing the opening of the diffuser shell 1 on the combustion chamber 6 side includes an annular portion 41b connected to the opening end of the diffuser shell 1, and an annular portion 41b.
And a cylindrical portion 44 integrally connected to the central opening of the housing 3 and projecting outward in the axial direction of the housing 3. This tubular part
In the internal space of 44, the igniter housed in the igniter collar 11
An igniting means 26 comprising an ignition device 10 and a transfer charge 12 ignited and burned by the igniter 10 is accommodated. Annular part 41b
Is formed so as to protrude outward in the radial direction of the diffuser shell 1, so that it can function as a flange when the gas generator is attached to the module.

The tubular portion 44 of the closure shell 40b
Is closed by a cap member 14 connected to the end of the transfer tube 13. Fire tube 13 connected to cap member 14
A plurality of heat transfer holes 15 are formed in the peripheral wall, and the internal space thereof communicates with the inside of the tubular portion 44 of the closure shell 2, that is, the space in which the ignition means 26 is housed. This allows
The flame generated by the operation of the igniting means 26 is ejected from the heat transfer hole 15 into the combustion chamber 6 through the transfer tube 13. In the present embodiment, this transmission tube 13
The front end side (that is, the filter means housing chamber 8 side) of the portion where the heat transfer hole 15 is formed is blocked by a stopper 45. This stopper 45 eliminates a useless space when igniting the transfer charge by blocking the internal space of the transfer tube 13 in a range not related to the transfer hole 15 and increases the pressure in the space in which the ignition means is accommodated. Thereby, the function of improving the ignitability of the transfer charge 12 is achieved.

The filter means accommodating chamber 8 houses the cylindrical filter means 7 as in the first embodiment. The filter means 7 has its end on the combustion chamber 6 side supported and fixed by a filter means support member 28, and the other end supported and fixed by a circular portion 42 of a closure shell 40a closing an opening on the filter means storage chamber 8 side. Have been. Thus, a gap 32 having a predetermined width is secured between the outer peripheral surface of the filter means 7 and the inner peripheral surface of the housing 3. The gap 32 functions as a gas flow path, and avoids a situation in which the combustion gas is concentrated near the gas outlet 4 when passing through the filter means 7.

The operation of this gas generator is as follows. When the igniter 10 is activated and the transfer charge 12 is ignited and burns, the flame passes through the transfer tube 13 and blows out from the transfer hole 15 into the combustion chamber 6. .
As a result, the gas generating agent 5 in the combustion chamber 6 is ignited and burned to generate a working gas, and this gas flows into the filter means accommodating chamber 8 through the through hole 18 of the baffle member 17.
Thereafter, the working gas is purified and cooled while passing through the filter means 7, breaks the seal tape 9 closing the gas outlet 4, and is discharged from the gas outlet 4. Embodiment 3 FIG. 6 shows an embodiment of the airbag apparatus of the present invention in the case of including a gas generator using 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 has an ignition determination circuit, and a signal from the semiconductor type 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 10 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 made of nylon (for example, nylon 66) or polyester, and its 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 an impact is detected by the semiconductor acceleration sensor 201 at the time of a vehicle collision, the signal is sent to the control unit 202, and when the impact 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 10 of the gas generator 200. Thus, the igniter 10 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.

[0053]

According to the present invention, the capacity of the gas generating agent can be changed while having a simple structure and easy to manufacture, and even if the ignition means has a normal output, the gas generation is ensured. It becomes a gas generator for an airbag that can ignite and burn the agent. In particular, by simplifying the sealing mechanism in the combustion chamber, it is possible to provide a gas generator for an airbag with further reduced manufacturing costs.

Further, in the gas generator including the structure in which the heat transfer tube and the plate member are combined, the amount of the gas generating agent accommodated in the combustion chamber can be appropriately changed.
A general-purpose gas generator is provided.

[Brief description of the drawings]

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

FIG. 2 is a perspective view showing a diffuser shell of the gas generator shown in FIG.

FIG. 3 is a cross-sectional view showing a diffuser shell according to another embodiment, in which (a) is a cross-sectional view along a length direction;
(B) is a sectional view orthogonal to the length direction.

FIG. 4 is a perspective view showing a diffuser shell according to still another embodiment.

FIG. 5 is a sectional view along a length direction showing an airbag gas generator according to another embodiment.

FIG. 6 is a schematic diagram showing an airbag device of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Diffuser shell 3 Housing 4 Gas outlet 5 Combustion chamber 6 Gas generating agent 7 Filter means 8 Filter means accommodating chamber 9 Seal tape 13 Fire tube 17 Baffle member 50 Gas outlet row 60 Gas outlet group

Claims (11)

[Claims] 1. A gas generator for an air bag comprising: a housing having a plurality of gas outlets on a peripheral wall; and an ignition means operated by an impact and gas generation means ignited and burned by the ignition means. The gas outlets are arranged in the axial direction of the housing to form a gas outlet row, and the gas outlet rows are arranged in the vicinity of two to six rows in the circumferential direction of the housing, and the gas exhaust ports are arranged in a row. A gas generator for an airbag, wherein a group of outlets is formed, and the group of gas discharge ports is arranged at predetermined intervals in a circumferential direction of the housing. 2. The airbag according to claim 1, wherein the gas outlet group is adjusted so that the central angle between the gas outlets adjacent in the circumferential direction of the housing is in the range of 10 to 30 °. For gas generator. 3. The gas generator for an airbag according to claim 1, wherein the gas outlet groups are formed at intervals of a central angle of 60 to 120 ° in a circumferential direction of the housing. 4. The gas exhaust port array constituting the gas exhaust port group, wherein the gas exhaust ports constituting the gas exhaust port row have different diameters. A gas generator for an airbag as described in the above. 5. The gas generator for an air bag according to claim 1, wherein each of the gas outlet groups is closed with one seal tape for each gas outlet group. 6. A width of the gas outlet group is 2 to 2 times larger than a width of a single sealing tape closing each gas outlet group.
The gas generator for an airbag according to any one of claims 1 to 5, wherein the gas generator is adjusted to be smaller by 20 mm. 7. A gas generator for an air bag, comprising: a housing having a plurality of gas discharge ports on a peripheral wall; and an ignition means operated by impact and a gas generation means ignited and burned by the ignition means. The gas outlets are arranged in the axial direction of the housing to form a row of gas exhaust ports, and the row of gas exhaust ports are arranged at predetermined intervals in the circumferential direction of the housing. For gas generator. 8. The gas generator for an airbag according to claim 7, wherein the gas outlet rows are closed with one seal tape for each row. 9. The gas generator for an airbag according to claim 1, wherein the housing is formed in a cylindrical shape longer in an axial direction than in a radial direction. 10. A housing in which a combustion chamber for accommodating gas generating means and a filter means accommodating chamber for accommodating filter means are formed adjacent to each other in the axial direction of the housing. The gas generator for an airbag according to any one of claims 1 to 9, wherein the group of gas outlets is formed in a peripheral wall of the housing in a range in which an inner side is a filter means accommodating chamber. 11. A gas generator for an airbag, an impact sensor that senses an impact to operate the gas generator, an airbag that expands by introducing gas generated by the gas generator, and the airbag. And a module case for accommodating the
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 10.