JP2554134B2 - Gas generator for airbag deployment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial application] The present invention relates to an airbag deployment used to deploy airbags such as airbags for collision safety devices, life bags, rubber boats, escape chutes, etc. by gas. TECHNICAL FIELD The present invention relates to a gas generator for use in an air bag, and more particularly to a gas generator for air bag deployment that can replenish a shortage of gas necessary for deploying an air bag with air.

[Conventional technology]

Conventionally, in a passenger car, a collision safety device for protecting a driver from a shock at the time of a collision is, for example, an airbag having a volume of 60 liters and an airbag deployment gas for deploying the airbag with gas. It is composed of a generator and, at the time of a collision of a passenger vehicle, ignites and combusts a gas generant consisting of explosives or a similar composition filled in a gas generator for expanding an airbag, and generates an air bag by the generated gas. It deploys instantly to protect the driver from collisions and prevent serious injury to the driver.

At this time, the amount of the gas generating agent required to deploy the airbag is 70 to 100 g, and the total weight of the gas generator main body containing the gas generating agent is 600 to 1100 g.

[Problems to be Solved by the Invention]

However, in such a conventional air bag deployment gas generator, since the deployment of the air bag is performed only by the generated gas by the combustion of the gas generating agent, even an air bag having a volume of 60 liters, The amount of gas generant required for its development is relatively large at 70-100g,
Along with this, the volume of the combustion chamber of the gas generator body increases,
The gas generator becomes relatively large and heavy.

On the other hand, if the amount of gas generating agent used is reduced, it is possible to make the gas generator smaller and lighter, but on the other hand, the amount of gas generated decreases, so the deployment of the airbag becomes insufficient,
The function as a collision safety device deteriorates. Therefore,
It becomes necessary to supplement the shortage with air or the like.

Therefore, it is conceivable to incorporate an air ejector that sucks air by high pressure gas, or a vapor ejector into the gas generator, but since the pressure of the primary high pressure gas of this type of ejector is as low as 10 kg / cm ² or less, The ejector itself must be made large in order to be able to suck in a large amount of air in a few tens of milliseconds, like an airbag for a collision safety device. Along with this, the gas generator becomes large and heavy, and it cannot be used as an air bag for an automobile.

In order to solve such a problem, the applicant of the present invention
We filed an application for a gas generator for deploying an air bag in No. 62-29339 and Japanese Patent Application No. 62-29340.

The gas generator for deploying an air bag of Japanese Patent Application No. 62-29339 has a housing body having an opening on the air bag connecting side,
A combustion chamber that is formed in the center of the housing body to generate high-pressure gas by burning a gas generating agent, and a ring shape by arranging the combustion chamber on the opening side in the housing body so as to be separated from the inner wall by a desired distance. And a partition wall for introducing high-pressure gas from the combustion chamber into the mixing chamber, and a high-pressure gas introduction portion for the mixing chamber by the partition wall, which is provided with high pressure toward the opening side of the mixing chamber. It is provided with a ring-shaped nozzle that ejects gas at a high speed, and an air suction port formed in the housing body along the nozzle.

Further, the gas generator for deploying an air bag of Japanese Patent Application No. 62-29340 has a housing body, a large-diameter air introduction opening formed in the central portion of the housing body along the axial direction thereof, and the housing body. A high pressure gas by combusting a gas generating agent formed on the outer peripheral side in the housing body and a mixing chamber in the center of the housing, which is communicated with the air introduction opening in line with the axis and communicates with the air bag. And a nozzle for injecting high-pressure gas from the combustion chamber at a high speed toward the opening side of the mixing chamber, which is formed in large numbers along the entire circumference at the joint between the air introduction opening and the mixing chamber. It is equipped with.

Since these air bag deployment gas generators are provided with the air intake port or the air introduction opening, respectively, the amount of the gas generant used can be reduced without hindering the deployment of the air bag, and It is small, lightweight and highly safe.

However, since these air bag deployment gas generators are simply provided with the air intake port or the air introduction opening, the combustion gas of the gas generating agent is discharged into the atmosphere through the air intake port or the air introduction opening. There is a risk.

The present invention solves the above problems, and an object of the present invention is to provide a gas generator for airbag deployment that can reliably prevent the release of combustion gas of a gas generating agent into the atmosphere. .

[Means for solving the problem]

The gas generator for airbag deployment of the present invention is a combustion chamber that generates a high-pressure gas by burning a gas generating agent that is housed inside, and a charging chamber that is arranged so as to surround the combustion chamber, An intake chamber that surrounds the charging chamber, a first nozzle that communicates the combustion chamber and the charging chamber, a second nozzle that communicates the charging chamber and the suction chamber, and the intake chamber A third nozzle having one end opened and the other end opened to an airbag, an intake hole formed in the intake chamber and opening to the atmosphere, and arranged in the intake hole and opened only from the atmosphere side to the intake chamber side. And a check valve.

[Work]

In the gas generator for airbag deployment of the present invention, when the gas generating agent contained in the combustion chamber burns, a high-pressure gas is generated in the combustion chamber, and the combustion gas causes the combustion chamber and the charging chamber to communicate with each other. After passing through one nozzle, it flows into the charging chamber,
Then, after passing through a second nozzle that communicates the charging chamber and the intake chamber, it flows into the intake chamber, and then passes through a third nozzle that has one end opened to the intake chamber and the other end opened to the airbag. Spill into the airbag.

On the other hand, due to the flow of the combustion gas into the intake chamber, the inside of the intake chamber is in a negative pressure state, whereby the check valve arranged in the intake hole formed in the intake chamber and opening to the atmosphere is opened,
Air in the atmosphere flows into the intake chamber, and together with the combustion gas,
It flows from the third nozzle to the airbag.

At the beginning and the end of the combustion of the gas generant, the pressure in the intake chamber may become higher than the atmospheric pressure. At this time, the check valve closes the intake hole, so that the combustion gas is discharged to the outside. Will not be released to.

〔Example〕

An embodiment of the present invention will be described below in detail with reference to the drawings.

FIG. 1 and FIG. 2 show an embodiment of a gas generator for airbag deployment according to the present invention, in which reference numeral 11 is used.
Shows the combustion chamber in which the gas generating agent is housed.

At the center of the combustion chamber 11, an igniter and an ignition charge for burning the gas generating agent are arranged.
A combustion chamber filter is arranged along the inner circumference of 11.

Further, a charging chamber 13 that concentrically surrounds the combustion chamber 11 and flows in the gas that has passed through the combustion chamber filter is arranged in an annular shape, and the combustion chamber 11 and the charging chamber 13 have a first nozzle 15 Is communicated by.

 A filling chamber filter is housed in the filling chamber 13.

An intake chamber 17 is concentrically surrounded by the intake chamber 17, and the intake chamber 17 and the intake chamber 17 are communicated with each other by a second nozzle 19.

One end of the third nozzle 21 is opened in the intake chamber 17,
The other end of the third nozzle 21 is opened to the airbag. The third nozzle 21 has a larger diameter than the second nozzle 19, and is arranged on the same axis as the second nozzle 19.

An intake hole 23 that opens into the atmosphere is formed in the intake chamber 17, and a check valve 25 that is opened only from the atmosphere side to the intake chamber 17 side is arranged in the intake hole 23.

In the figure, reference numeral 27 indicates an attachment hole for attaching the airbag-producing gas generator to the airbag, and the airbag is attached to the lower side of the attachment hole.

3 and 4 show the intake holes formed in the intake chamber 17.
23 shows a check valve 25 arranged at 23.
Is formed of, for example, hard rubber or metal.

The check valve 25 has a circular V-shaped cross section, and a plurality of elongated holes 35, 37 are formed on both sides of the central portion 33 of the valve body 31 at a predetermined angle. There is.

In the air bag expansion gas generator configured as described above, when the gas generant contained in the combustion chamber 11 burns, high-pressure gas is generated in the combustion chamber 11, and this combustion gas is used as the combustion chamber 11. After passing through the first nozzle 15 that communicates with the charging chamber 13, it flows into the charging chamber 13, and thereafter, the charging chamber 13 and the suction chamber 17
After passing through a second nozzle 19 that communicates with, the air flows into the intake chamber 17, and then passes through a third nozzle 21 having one end opened to the intake chamber 17 and the other end opened to the airbag, and flows out to the airbag. To do.

On the other hand, when the combustion gas flows into the intake chamber 17, the intake chamber 17
When the inside becomes a negative pressure state, as shown in FIG. 5, the check valve 25 arranged in the intake hole 23 of the intake chamber 17 is formed in the intake chamber 17 on the intake chamber 17 side. It moves until it comes into contact with the locking portion 39, and there is a gap between the central portion 33 of the valve body 31 and the valve seat 41.
43 is formed, the check valve 25 is opened, and the air in the atmosphere is
As shown by arrows in FIG. 5, the gas flows into the intake chamber 17 through the long holes 35 and 37, and flows out from the third nozzle 21 to the airbag together with the combustion gas.

At the beginning and the end of the combustion of the gas generating agent, the pressure in the intake chamber 17 may be higher than the atmospheric pressure. At this time, as shown in FIG. Since the hole 23 is closed, the combustion gas is not released to the outside.

That is, in the air bag deployment gas generator configured as described above, since the check valve 25 that is opened only from the atmosphere side to the intake chamber 17 side is arranged in the intake hole 23, the inside of the intake chamber 17 is When the pressure becomes higher than the atmospheric pressure, the check valve 25 closes the intake hole 23, so that the discharge of the combustion gas into the atmosphere can be reliably prevented.

Further, in the air bag deployment gas generator configured as described above, since the intake hole 23 is provided, it is possible to reduce the amount of the gas generant used without hindering the deployment of the air bag, In addition, it is small, lightweight and highly safe.

〔The invention's effect〕

As described above, according to the present invention, the air bag expansion gas generator is arranged so as to surround the combustion chamber and the combustion chamber that generates high-pressure gas by burning the gas generating agent contained therein. A charging chamber, an intake chamber that surrounds the charging chamber, and a first chamber that connects the combustion chamber and the charging chamber.
A nozzle, a second nozzle that connects the charging chamber and the intake chamber, a third nozzle that opens at one end to the intake chamber and opens at the other end to the air bag, and that is formed in the intake chamber and opens to the atmosphere Since it is composed of an intake hole and a check valve arranged in the intake hole and opened only from the atmosphere side to the intake chamber side, it is possible to reliably prevent the combustion gas from being released into the atmosphere. There are advantages.

[Brief description of drawings]

FIG. 1 is a vertical cross-sectional view showing an embodiment of a gas generator for expanding an air bag of the present invention. FIG. 2 is a top view of FIG. FIG. 3 is a top view of the check valve of FIG. FIG. 4 is a longitudinal sectional view of the check valve of FIG. FIG. 5 is a vertical cross-sectional view showing a state in which the check valve is opened in the air bag deployment gas generator of FIG. [Description of symbols of main parts] 11 ... Combustion chamber 13 ... Filling chamber 15 ... First nozzle 17 ... Intake chamber 19 ... Second nozzle 21 ... Third nozzle 23 ... Intake hole 25 ... …Check valve.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Minoru Hayashi 30-5 Higashionuma, Shirakawa City, Fukushima Prefecture

Claims (1)

(57) [Claims] 1. A combustion chamber for generating a high-pressure gas by burning a gas generating agent contained therein, a charging chamber arranged to surround the combustion chamber, and a charging chamber surrounding the charging chamber. An intake chamber that is arranged, a first nozzle that communicates the combustion chamber and a charging chamber, and a second nozzle that communicates the charging chamber and the intake chamber,
A third nozzle having one end opened to the intake chamber and the other end opened to the airbag, an intake hole formed in the intake chamber and opened to the atmosphere, and arranged in the intake hole from the atmosphere side to the intake chamber side. A gas generator for expanding an air bag, comprising a check valve that is opened only.