JP3800445B2 - Airbag device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention is an airbag device for ensuring the safety of a driver and an occupant from an impact caused by a collision accident of an automobile, etc., and in particular, the airbag deployment performance and the airbag damage prevention performance at the time of deployment. The present invention relates to an airbag device using an inflator based on an excellent novel concept.
[0002]
[Prior art]
The basic structure of a conventional inflator includes a gas generating agent that generates a high-pressure gas that is a working fluid for deploying an airbag, and an ignition that ignites the gas generating agent in order to burn and gasify the gas generating agent. And a cooling filter member for collecting slag, which is a high-temperature burning residue generated by the combustion of the gas generating agent, and cooling the gas at the same time. Ignition, followed by rapid combustion of the slag generating agent, and a relatively clean gas from which the slag has been removed from the generated high-pressure gas is ejected from the opening on the outer wall of the housing into the airbag, causing the bag to expand. I have to.
[0003]
Moreover, in the concrete structural design, consideration is given to ensure the functionality of unfolding the bag reliably. Specifically, the type and amount of the gas generating agent is determined in order to ensure the combustion state so as to reach a pressure that can overcome the atmospheric pressure and inflate the bag. To prevent the slag from directly hitting the bag and burning and melting the bag itself, the slag is prevented from flowing out of the inflator and the combustion gas is jetted into the bag after cooling. Here, it is the cooling filter member that plays the role of slag collection and gas cooling.
[0004]
In other words, in the conventional inflator, (1) design conditions are to remove slag as much as possible inside the inflator, and (2) to cool the gas to such an extent that it does not damage even if the blown gas hits the bag directly, An amount of cooling filter member sufficient to achieve this condition is disposed in the housing. In particular, in the conventional method using sodium azide as a gas generant, when sodium azide burns, sodium oxide that is extremely harmful to the human body and the environment is produced, so this harmful substance is contained in the slag. Yes. It is an important role of the filter member to remove the harmful substances as much as possible. For this purpose, a sufficient amount of the cooling filter member is disposed in the inflator. The ideas of (1) and (2) are the center of the inflator design concept even if the azide gas generating agent is changed to tetrazole or other nitrogen-containing organic compound type gas generating agents.
[0005]
[Problems to be solved by the invention]
However, the incorporation of this sufficient amount of cooling filter member is inconvenient. That is, the pressure of the jet gas is reduced by collecting the slag and cooling the jet gas. This will be described based on FIG. 6 showing the relationship between the time (t) from the start to the end of the operation of the inflator and the mass velocity (g / sec, hereinafter referred to as “Mf”) of the jet gas. In all inflators, when the gas generant is ignited at time t0, Mf increases rapidly, and after reaching the maximum value (Mfp), decreases in a short time. Here, when the amount of the cooling filter member is larger than the amount of the gas generating agent and the jet gas is supercooled, it is necessary to obtain an appropriate development as shown by the one-dot chain line in the figure. The airbag deployment is completed without reaching the reference gas mass flow rate (Mfs), and the airbag is incompletely deployed. On the other hand, in the conventional general example (illustrated by a dotted line in the figure) in which sufficient gas generant is loaded, it is designed so that Mf exceeding Mfs can be obtained against cooling by the cooling filter member. Yes. The period (t1) exceeding Mfs indicates that the airbag is in a predetermined deployment state, but the predetermined deployment time (t1) of the airbag is relatively short. However, if a high gas mass velocity (Mf) is obtained from the initial stage (shown by the solid line in the figure), the time (t2) exceeding the reference value (Mfs) becomes relatively long, and stable airbag deployment can be obtained. I understand that
[0006]
Therefore, as shown by the solid line, it can be said that an inflator that can quickly deploy the airbag at a high pressure and maintain a flow rate of Mfs or higher that can effectively function as an airbag for a long time is preferable. Therefore, as a measure for realizing this preferred form, a measure using a large amount of gas generating agent can be considered, but this measure is not preferable because it leads to an increase in the size of the inflator.
[0007]
An increase in the amount of gas generating agent appears as an increase in the amount of slag generation. If the housing capacity is kept constant, the cooling filter member will decrease by the amount of increase in the gas generating agent. Cannot be sufficiently removed, and the bag is likely to be thermally damaged. Especially for inflators, there is a strong demand for downsizing and weight reduction, and there is always a desire to develop a bag with a larger capacity with the smallest possible inflator, so the capacity of the housing is reduced. The direction is trend.
[0008]
On the other hand, measures to improve the slag removal efficiency of the cooling filter member can be considered for this problem, but it is not easy to develop a cooling filter member that enhances the slag removal efficiency while maintaining good combustion conditions. .
[0009]
As another measure, a gas generating agent having a smaller amount of generated slag even if the amount of gas generated is the same, or more positively adopting a gas generating agent having a small amount of generated slag and a large amount of generated gas. In other words, various measures for improving the gas generating agent itself have been proposed. However, there is another problem in this case. That is, a gas generating agent having a large gas generation amount generally has a large calorific value, and it is difficult to achieve a cooling balance, and it is difficult to ensure appropriate combustion conditions. It is not easy to develop the gas generating agent itself because a part of the member may flow out to cause significant damage to the bag.
[0010]
On the other hand, when the gas generating agent is limited to those other than azide, there is a situation that the harmfulness of slag is significantly reduced. That is, in the case of non-azide gas generating agents that use nitrogen-containing organic compounds such as tetrazoles, which are being developed and put to practical use in recent years, as fuels and alkali metal or alkaline earth metal oxidants, it is unavoidable. The carbon dioxide gas generated in the oxidant and the metal oxide derived from the oxidant react to produce a carbonate, which is rendered harmless.
[0011]
The present invention has been made in view of the above circumstances, and its object is to solve the above-mentioned problems all at once, and the airbag deployment performance and airbag damage during deployment while being small in size. It is in providing an inflator having excellent prevention performance.
[0012]
[Means for Solving the Problems]
In order to solve the above problems, the present inventors first studied from various viewpoints a method for increasing Mf without changing the amount of the gas generating agent, but from the viewpoint of increasing the amount of the gas generating agent. . Microscopic observations were also made when heat damage occurred in the bag.
[0013]
As a result, conventionally, it is considered that the cause of the bag damage exists in the point where the high temperature gas itself or mainly the high temperature gas directly hits the bag. As a solution to this problem, various devices for reducing the temperature of the gas are performed. It has become common sense, but it turns out that the common sense is not always true.
[0014]
In other words, since the gas itself has a small heat capacity, even if high-temperature gas directly hits the bag, heat concentration is difficult to occur and the bag expands before it affects the bag due to heat transfer from the high-temperature gas, and then immediately forms on the bag. It was found that there was no particular problem when it was released from the vent hole. Rather, it has been found that the cause of damage is high-temperature molten slag having a large heat capacity, and the heavier, that is, the slag having a relatively large particle size, is more likely to cause thermal damage to the airbag.
[0015]
Therefore, the present inventors overturned the conventional idea that the layout design of the filter member has been made for the purpose of limiting the slag discharge allowable amount to, for example, 2 g or less. The energy of the slag is positively utilized for the bag development by discharging with it to obtain a large value of Mf, and the high-temperature slag with relatively large particles which damages the bag as described above, that is, the airbag and the inflator Can be solved all at once, and as described above, slag can be generated even in non-azide gas generating agents. Taking advantage of the low hazards (advantages) of the present invention, it was concluded that it was suitable for practical use from a safety standpoint, and the present invention was completed.
[0016]
That is, the air bag apparatus of the present invention for achieving the above object cools and collects an air bag, a gas generating agent for deploying the air bag, gas generated by combustion of the gas generating agent, and slag. An air bag apparatus comprising a cooling filter member and an inflator in which an igniter for igniting the gas generating agent is housed in a housing, wherein the cooling filter member in the inflator is only a part of the generated slag. The remaining portion of the slag is ejected into the airbag from the opening formed in the housing, and a relatively large slag of the ejected slag is formed between the airbag and the opening. The remaining slag with a relatively small particle size is fed into the airbag together with the gas flow to prevent rapid cooling of the gas. It is. That is, the present invention has a great feature in that the slag collection by the cooling filter member in the inflator is incomplete and the slag is positively contained in the gas flow ejected from the inflator.
As a means for collecting the slag having a relatively large particle size, a cooling metal member for cooling and collecting slag is brought into contact with a slag-containing gas flow ejected from the opening near the outer wall of the housing. There is a method of disposing slag having a relatively large particle size in the slag-containing gas flow to be attached to the cooling metal member and removing it.
[0017]
As a result, among the high-temperature gas ejected from the inflator and the high-temperature slag that was not intentionally collected inside the inflator, those having a relatively large particle size were placed outside the inflator before reaching the airbag. It collides with a cooling metal member having a large heat capacity, and is efficiently collected and cooled. That is, only high-temperature slag having a relatively large particle size or heavy high-temperature slag containing molten metal is collected by being cooled and solidified on the surface of the gold member. Therefore, a large particle size slag that causes damage to the bag, that is, a large particle size, and consequently a high temperature slag having a large heat capacity, is separated from the gas and removed with a cooling metal member before touching the bag. Like. The remaining high-temperature slag with a relatively small heat capacity is actively accompanied (wake) by the gas.
[0018]
On the other hand, even if the gas hits the cooling metal member, the surface area of the cooling metal member is much smaller than that of the cooling filter member arranged in the inflator, that is, the heat transfer area with the gas is very small. The loss of is very small. In addition, as described above, since a relatively large amount of high-temperature slag with a small heat capacity is accompanied (wake) in the gas, the fine high-temperature slag serves as a heat source to prevent the gas temperature from decreasing and the gas is retained. Internal energy, that is, sufficient pressure energy necessary for the deployment of the bag, flows into the bag while being retained in the jet gas.
[0019]
As a result, compared with the conventional inflator, the gas energy generated in the inflator is efficiently utilized, and a sufficient deployment pressure can be obtained with a small amount of gas generating agent. In other words, if the amount of the gas generating agent is the same, the inflator can obtain a higher deployment pressure. Therefore, according to the present invention, it is possible to further promote the downsizing of the inflator. Furthermore, since the heat capacity of the fine slag in the gas is considerably larger than the heat capacity of the gas, heat is replenished to the gas that is cooled by contact with the outside world and causes a decrease in temperature. The rapid decrease in the gas temperature and the gas pressure is prevented, and as shown by the solid line in FIG. 6, the gas outflow rate of Mfs or higher that effectively functions as a cushioning material for the airbag is maintained for a long time. It will be a thing.
[0020]
In another aspect of the present invention, the filling amount of the cooling filter member in the inflator is adjusted so that the slag retention amount of the slag-containing gas ejected from the opening in the above invention is 2 to 10 g. 2 g is a minimum amount necessary for effectively exhibiting the effect of increasing the internal heat energy of the gas by using the heat capacity of the slag as a heat source by entraining the slag in the jet gas. On the other hand, if it exceeds 10 g, there is a possibility that the safety permissible standard (the permissible standard for releasing harmful components contained in the slag) may no longer be satisfied as an inflator.
[0021]
In addition, according to another aspect of the present invention, the amount of slag collected by the cooling metal member by the contact between the cooling metal member and the slag-containing gas ejected from the opening in the above invention is 1 to 2 g, and the collection efficiency 10 to 30%. If it is within this range, the effects of the above invention can be surely enjoyed. On the other hand, if this range is exceeded, the amount of slag entrained as a heat source in the jet gas is reduced, and the efficiency of the internal energy of the gas used to expand the bag This is because large slag having a relatively large heat capacity cannot be completely collected, and sometimes the bag may be damaged.
[0022]
According to another aspect of the present invention, the upper end of the cooling member is positioned in a range of −45 ° to + 45 ° in the vertical direction with respect to a horizontal axis passing through the lower end of the housing outer wall opening. Further, the cooling metal member is arranged so that the cooling metal member is brought into contact with the jet gas flow. The gas to be ejected is a mixed layer flow of combustion gas and slag, but in microscopic observation, the larger diameter slag flows while floating below the mixed layer flow, and after gas ejection, Considering that the larger diameter slag tends to fall to the near side, the angle is selected as a suitable arrangement of the cooling member for reliably collecting the larger diameter slag. In this range, when adjusting the slag collection efficiency in accordance with changes in the type of gas generating agent and the combustion conditions, it is possible to easily cope with the required specifications for the inflator without greatly changing. In addition, from the viewpoint of reducing the size and weight of the inflator, it is preferable to set within a range of −45 ° to −20 °.
[0023]
In another aspect of the present invention, the contact surface with the jet gas in the cooling metal member is formed to be a rough surface, so that slag having a relatively large heat capacity can easily adhere to the surface. It is possible to increase the slag collecting effect. In addition, the arrangement area of the cooling metal member is saved correspondingly, thereby contributing to weight reduction. The rough surface can be formed by adding a metal mesh or the like to the surface in addition to roughening the surface itself. Of course, it is not limited to these means.
[0024]
Another aspect of the present invention is such that the jet gas contact surface of the chill member has an inclination angle of 30 ° to 120 ° with respect to the horizontal plane, so that the bag is developed. In order to reduce the loss of heat energy of the high-pressure gas to be effectively converted into work for the deployment of the bag, in particular, from the viewpoint of appropriately directing the gas flow 60 ° to A tilt angle of 100 ° is preferable.
[0025]
In another embodiment of the present invention, the cooling member is mounted and disposed at a position within 40 mm in the horizontal distance from the opening on the outer wall of the housing. This is because it becomes difficult to connect the inflator, that is, to assemble the airbag device.
[0026]
Further, according to another aspect of the present invention, as the arrangement form of the cooling metal member, the cooling metal member is directly connected to the side flange of the housing structure or indirectly through the inflator / airbag connecting member. It is intended to be attached to. This further facilitates downsizing of the inflator.
[0027]
The present invention is particularly effective when a non-azidized nitrogen-containing organic compound having a calorific value of 2000 Joules / g or more, preferably 2000-4500 Joules / g, is used as the gas generating agent. .
[0028]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 shows a main part of an airbag device according to an embodiment of the present invention, and is a cross-sectional explanatory view of a main part showing a state where the airbag is deployed. In FIG. 1, an inflator 1 includes a double short tube cylindrical housing 2 having an inner cylinder 3 and an outer cylinder 4, and an ignition chamber P is formed in the inner cylinder 3 inside the housing 2. A combustion chamber G and a cooling filter chamber F are formed between the cylinder 3 and the outer cylinder 4. In addition, 31 is an igniter and 32 is an enhancer.
[0029]
An inner wall 5 is disposed at the boundary between the combustion chamber G and the cooling filter chamber F, and cooling filter members 6 and 7 are disposed in the cooling filter chamber F. In this case, the cooling effect is mainly enhanced by the cooling filter member 6 and the slag collecting effect is enhanced by the cooling filter member 7. The ignition chamber P, the combustion chamber G, and the cooling filter chamber F communicate with each other through the openings 8 and 9, and the cooling filter chamber F and the outside of the inflator 1 communicate with each other through the opening 10.
[0030]
The loading amount of both the cooling filter members 6 and 7 is set to a volume capable of collecting only about 50 to 70% of the slag equivalent generated when the non-azide gas generating agent 11 as the gas generating agent burns. Has been. In other words, the loading amount of the cooling filter members 6 and 7 is determined so that about 2 to 10 g of slag is positively accompanied by the gas ejected from the opening 10.
[0031]
A cooling metal member 13 is erected on the side flange 12 of the housing 2 in the vicinity of the outer peripheral surface of the housing 2. Since this chill member 13 cools and collects slag having a large heat capacity in the jet gas as will be described later, the slag member 13 can be used for the amount of slag to be collected so that the temperature does not easily rise due to the attached slag. Although designed to have a sufficiently large heat capacity, the surface area need not be so large. Further, the upper end of the cooling metal member 13 substantially coincides with the horizontal axis passing through the lower end of the opening 10.
[0032]
Next, the operation of the inflator will be described with reference to FIG. The non-azide gas generating agent 11 is combusted by the ignition of the igniter 31 energized in response to the collision signal. The generated high-temperature gas containing a large amount of slag passes through the cooling filter members 6 and 7 and is ejected from the opening 10 into the bag 15. In this case, the cooling filter members 6 and 7 are loaded with an amount capable of collecting only about 50 to 70% of the amount corresponding to the slag generated when the gas generating agent 11 burns as described above. In other words, the gas passing through the opening 10 is positively accompanied by about 2 to 10 g of slag. For this reason, if the gas in this state is directly discharged into the bag 15, the bag 15 is surely damaged.
[0033]
Therefore, in the illustrated inflator, the high-temperature slag that was not intentionally collected by the cooling filter members 6 and 7 inside the inflator collides with the cooling member 13 having a large heat capacity outside the inflator and is efficiently cooled. At this time, only the relatively large-diameter molten slag or the large-diameter slag containing the molten metal cools, adheres to the metal member 13, and is collected by solidifying. That is, only the large-diameter slag having a large heat capacity that causes the damage to the airbag 15 is separated from the gas, cooled before being attached to the bag 15, and removed by the metal member 13. The remaining hot slag with a relatively small diameter and a small heat capacity is still entrained (floating) in the gas.
[0034]
On the other hand, even if the gas hits the cooling metal member 13, the surface area of the cooling metal member 13 is much smaller than the cooling filter members 6 and 7 arranged in the inflator 1, that is, the heat transfer area is very small. There is little heat transfer from the gas and very little energy loss. In addition to this, as described above, the gas has a relatively large amount of fine high-temperature slag with a small heat capacity (but with a large heat capacity compared to the gas), so that the heat capacity is large compared to this gas. The slag acts as a heat source to prevent a sudden drop in the gas temperature, and thus the pressure drop is small and the gas holding energy, that is, the energy necessary for the deployment of the bag is maintained, and the buffer as shown by the solid line in FIG. The function can be maintained for a long time.
[0035]
As a result, the inflator can obtain a sufficient deployment pressure even when the loading amount of the gas generating agent 11 is smaller than that of the conventional inflator. In other words, if the loading amount of the gas generating agent 11 is the same. The inflator can obtain a higher deployment pressure. Therefore, the inflator of the present invention can easily meet the demand for downsizing.
[0036]
The arrangement of the cooling metal member 13 may be set such that the upper end of the cooling metal member 13 becomes lower as the distance from the outer wall of the housing 2 is within a range of 40 mm at the maximum and the distance from the housing 2 increases. Specifically, as shown in FIG. 2, the upper end of the cooling metal member 13 is vertically within a range of −45 ° to + 45 °, preferably −45 ° to −45 ° with respect to the horizontal axis passing through the opening 10. What is necessary is just to arrange | position so that it may exist in the range of 20 degrees.
[0037]
Thereby, after gas ejection, only the slag with a large particle diameter that falls to the front lowering is efficiently collected, and the slag with a small particle diameter is actively entrained in the gas, and the gas is cooled by the metal member 13 The influence can be made almost unaffected. In addition, since the cooling member 13 has a configuration capable of appropriately changing the collection efficiency of slag having a large particle size, it has high versatility that can easily cope with various required specifications of the inflator. Further, as long as the cooling member 13 is mounted and disposed at a position within 40 mm in the horizontal distance from the opening 10, there is no problem in connection between the bag and the inflator, that is, in assembling the airbag device.
[0038]
As shown in FIG. 3, the jet gas contact surface 13a of the cooling metal member 13 is inclined 30 ° to 120 °, preferably 60 ° to 100 ° with respect to the horizontal plane, so that the jet gas flow from the opening 10 is appropriately By adopting a configuration in which the gas can be directed to the bag 15, it is possible to effectively convert the jet gas into work energy for developing the bag while avoiding a decrease in thermal energy of the gas that is intended to expand the bag 15.
[0039]
Further, as shown in FIG. 1, the cooling member 13 may be indirectly attached to the side flange 12 via an inflator / bag connecting member, instead of being directly disposed on the side flange 12 of the housing 2. The cooling member 21, 22, 23, 24 in FIG.4 and FIG.5 (a)-(c) is the example. That is, each of these cooling metal members 21 to 24 is a form example in which the holding metal member 18 of the bolt 16 and the cooling metal member 13 in FIG. 1 are just integrated, and the bolt and nut (25, 26). ), (27, 28), (29, 30), (31, 32). Reference numeral 33 denotes a reinforcing cloth.
[0040]
Further, the cross-sectional shape of the cooling member 21 shown in FIG. 4 is L-shaped, but the U-shaped configuration is such that the rising portion near the inflator 1 is cut off as shown in FIG. As shown in FIG. 5 (b), it is possible to change freely, such as a configuration in which the rising portion on the side far from the inflator 1 is cut off, or a U-shape as shown in FIG. 5 (c). . Furthermore, as a slag collecting member, in addition to the cooling metal member described above, a member having another shape structure may be adopted and disposed between the opening of the inflator and the airbag. Yes.
[0041]
In the inflator 1 shown in FIG. 1, an example in which a non-azidized gas generant is used as the gas generant 11 is shown. Among them, tetrazole, triazole, carbonamide, dicyandiamide, and guanidine are shown. In the case of using various exothermic nitrogen-containing organic compounds proposed to date and using a highly exothermic gas generating agent having a calorific value of 2000 Joules / g or more, it is sufficient in an inflator as in the prior art. If the air is cooled and ejected into the airbag, a large amount of cooling filter members are required, and the inflator must be increased in size. However, according to the present invention, the air bag is accompanied by high-temperature slag. Therefore, it is particularly advantageous in that the inflator can be miniaturized.
[0042]
【The invention's effect】
As described above, according to the present invention, the high-temperature gas ejected from the inflator and the high-temperature slag that was not intentionally collected inside the inflator are the cooling metal members having a large heat capacity installed outside the inflator, etc. It collides with the slag collecting member and is cooled and collected efficiently. At this time, only the molten slag having a relatively large particle size or the molten slag containing molten metal is collected by cooling and adhering to the metal member and solidifying, so that the largest cause of damage to the bag The large diameter slag is separated from the gas, cooled before reaching the bag, and removed by the gold member. As a result, the remaining slag having a relatively small particle size is positively entrained in the gas.
[0043]
On the other hand, even if the gas collides with the cooling metal member, the surface area of the cooling metal member is much smaller than that of the cooling filter member disposed in the inflator, that is, the heat transfer area with the gas is very small. The loss of heat energy is very small. In addition to this, as described above, a relatively large amount of slag with a small particle size is suspended in the gas, so fine slag, which has a large heat capacity compared to the gas, acts as a heat source and lowers the gas temperature. And the pressure drop is prevented, so that abundant energy necessary for deploying the gas bag can be secured.
[0044]
Therefore, it is an inflator that can obtain a sufficient bag deployment pressure even when the loading amount of the gas generating agent is smaller than that of the conventional inflator, in other words, if the loading amount of the gas generating agent is the same, An inflator with a high bag deployment pressure can be obtained. Therefore, according to the inflator of the present invention, it is possible to easily meet the demand for downsizing.
[0045]
Moreover, if the amount of the cooling filter member in the inflator is adjusted so that the amount of slag in the slag-containing gas ejected from the opening of the inflator is 2 to 10 g, the above effect can be further exhibited. It is possible to provide an inflator that can sufficiently satisfy safety tolerance standards (acceptance standards for harmful components contained in slag in the vehicle interior).
[0046]
Further, the contact between the cooling metal member and the slag-containing gas ejected from the opening causes the amount of slag collected by the cooling metal member to be 1 to 2 g, so that the collection efficiency is 10 to 30%. If the metal member is designed, the above effect becomes more remarkable. In particular, since slag having a relatively large particle diameter can be completely collected, the possibility of bag damage can be reliably eliminated.
[0047]
Further, the cooling metal member is arranged so that the upper end of the cooling metal member is in the range of −45 ° to + 45 ° in the vertical direction with respect to the horizontal axis passing through the lower end of the housing outer wall opening. The contact probability between the member and the jet gas flow is made large, and a large-sized slag falling downward after the gas jet can be efficiently and reliably collected. On the other hand, the gas is hardly affected by the cooling by the cooling metal member, and flows into the bag while maintaining high-temperature and high-pressure energy. Furthermore, the inflator can also be made highly versatile that can easily cope with various requirements, and in addition, there is no problem in connection between the bag and the inflator, that is, the assembly of the airbag device.
[0048]
Further, by forming the contact surface with the jet gas in the cooling metal member as a rough surface, the efficiency of attaching slag to the surface is increased. Moreover, by making the contact surface of the jet gas on the cooling metal member to have an inclination angle of 30 ° to 120 ° with respect to the horizontal plane, the jet gas can be blown out without losing as much heat energy as possible of the gas to be deployed in the bag. Gas can be effectively converted into work energy for bag deployment.
[0049]
Further, by mounting and arranging the cooling metal member at a position within 40 mm in the horizontal distance from the opening on the outer wall of the housing, an inflator can be obtained without any concern on the assembly surface. Further, as a cooling member arrangement form, the cooling member can be reduced in size by attaching the cooling member directly to the side flange of the housing structure or indirectly through the inflator / airbag connecting member. It is possible to meet the demands of the assembly and to secure the freedom of assembly work.
[0050]
Even if a non-azidized gas generating agent having a large calorific value of 2000 to 4500 joules / g is used as the gas generating agent, it is small without increasing the filling amount of the cooling filter member in the inflator. A lightweight inflator can be obtained.
[Brief description of the drawings]
FIG. 1 is a cross-sectional explanatory view of a main part showing the configuration and operation of an airbag apparatus according to an embodiment of the present invention.
FIG. 2 is a main part explanatory view showing the arrangement range of cooling metal members in relation to the opening.
FIG. 3 is a main part explanatory view showing an inclined arrangement state of a cooling metal member.
FIG. 4 is a main part explanatory view showing a configuration in which a cooling metal member is indirectly attached to a side flange of an inflator via an inflator / bag connecting member.
FIG. 5 is a modified example in which the cooling metal member is indirectly arranged on the inflator, and (a) is a configuration in which a rising part on the side close to the inflator is cut out from the U-shaped part as the cooling metal member. (B) is the structure which cut off the rising part on the side far from an inflator, and (c) is principal part explanatory drawing which respectively shows the structure with a U-shape.
FIG. 6 is a graph showing a temporal change in the gas flow rate of the inflator, in which a solid line indicates an example of the present invention and a dotted line indicates a conventional example.
[Explanation of symbols]
1 Inflator
2 Housing
3 inner cylinder
4 outer cylinder
5 Inner wall
6,7 Cooling filter member
8, 9, 10 opening
11 Gas generating agent
12 Side flange
13, 21, 22, 23, 24 Cooling member
15 airbag
25, 27, 29, 31 bolts
26, 28, 30, 32 Nut
31 Igniter
32 Enhancer

Claims (6)

Airbag (15), gas generating agent (11) for deploying the airbag, and cooling filter members (6, 7) for cooling and collecting the gas and slag generated by combustion of the gas generating agent (11) And an inflator (1) in which an igniter (31) for igniting the gas generating agent (11) is housed in a housing (2), respectively,
The cooling filter members (6, 7) in the inflator (1) collect only a part of the generated slag, and the remaining portion of the slag is an air bag through an opening (10) formed in the housing (2). No way to erupt inside,
Of the slag contained in the jet gas, slag having a relatively large particle size is collected by a slag collecting member (13) disposed between the opening (10) and the airbag (15),
The slag collecting member is a cooling metal member (13) disposed near the outer wall of the housing (2) and at a position in contact with the slag-containing gas flow ejected from the opening (10).
In the cooling member (13), the amount of slag to be cooled and collected is 1 to 2 g, and the efficiency of collecting slag in the slag-containing gas ejected from the opening (10) is 10 to 30%. In order to bring the cooling metal member (13) into contact with the slag-containing gas ejected from the opening (10 ), the upper end of the cooling metal member (13) is the opening of the housing (2). It is arranged so as to exist in the range of −45 ° to −20 ° in the vertical direction with respect to the horizontal axis passing through the lower end of the portion (10),
The air bag apparatus characterized in that the remaining slag having a relatively small particle diameter in the jet gas is supplied into the air bag together with the gas flow to prevent rapid cooling of the gas.   The airbag apparatus according to claim 1, wherein a contact surface of the jet gas in the cooling metal member (13) has an inclination angle of 30 ° to 120 ° from a horizontal plane.   The airbag apparatus according to claim 1 or 2, wherein an inclination angle of the cooling metal member (13) is in a range of 60 to 100 °.   The cooling metal member (13) is mounted and arranged at a position within 40 mm as a horizontal distance from the opening (10) of the housing (2). The airbag apparatus as described.   The cooling member (13) is directly connected to the side flange (12) of the housing structure (2) or indirectly to the side flange (12) via the inflator / airbag connecting members (16, 17). The airbag device according to any one of claims 1 to 4, wherein the airbag device is attached.   The airbag apparatus according to any one of claims 1 to 5, wherein the gas generating agent (11) is a non-azidized gas generating agent having a calorific value of 2000 Joules / g or more.

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