JPH081984Y2 - Gas generator for airbag - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention relates to a gas generator used in an airbag safety device for ensuring the safety of a driver and an occupant of a vehicle from an impact such as a collision accident of the vehicle. .

[Conventional technology]

Conventionally, as this type of air bag gas generator, a cylindrical container partitioned into a central portion, an intermediate portion, and an outer peripheral portion in communication with each other, an ignition means accommodated in the central portion, and an intermediate portion thereof are accommodated. There is known a gas generator for an air bag, which is provided with the above-mentioned gas generating agent and a filter attached to the outer peripheral portion thereof. An example of such an airbag gas generator will be described with reference to FIG. The cylindrical container 50 includes an upper container 51 and a lower container 52. The upper container 51 has an outer peripheral wall 53, an intermediate wall 54 and an inner peripheral wall 55, and the lower container 52 has a lid shape. And
Both are integrated by pressure welding or welding and are divided into a central portion 56, an intermediate portion 57, and an outer peripheral portion 58. In the central portion 56, an electric heater 60 that operates by receiving a current supply via a collision sensor 59 and an ignition powder 61 that covers the electric heater 60 are stored. The electric heater 60 and the ignition charge 61 form an ignition means. The gas generating agent 62 and the cooling screen 63 are housed in the intermediate portion 57. A filter assembly 65 is attached to the outer peripheral portion 58 via a space 64. Further, the outer peripheral wall 53, the intermediate wall 54, and the inner peripheral wall 55 are provided with gas holes 53A, 54A, 55A, respectively. Next, the operation of the airbag gas generator having the above-described configuration will be described. The hot air of the ignition charge 61 ignited by the electric heater 60 flows into the intermediate portion 57 through the gas holes 55A. This hot air causes a gas generating agent
62 causes a chemical reaction and gasifies. This gas flow is cooled by the cooling screen 63, passes through the gas holes 54A, and enters the space 6
Up to 4. Further, dust is taken by the filter assembly 65 and ejected from the gas holes 53A into the airbag (not shown).

[Problems to be solved by the device]

In the gas generator described in the related art, when it is desired to increase the capacity of the gas generating agent, it is necessary to increase the diameter D of the intermediate wall 54. If the diameter D is increased, the space L in the space 64 becomes narrower and the gas flow becomes worse.
That is, the outer diameter of the cylindrical container 50 itself must be increased. This gas generator is inconspicuously attached to a handle or the like, and is required to be as small as possible. However, there is a problem that the cylindrical container 50 itself becomes large as the amount of the gas generating agent increases, and the gas generator becomes large. Furthermore, many gas holes are formed in the outer peripheral wall 53 of the cylindrical container 50.
Since the structure is provided with 53A, there is also a problem in that the wall thickness needs to be increased in order to withstand the instantaneous pressure (reaching 100 atmospheric pressure or more) in the cylindrical container 50.

The present invention has been made in view of the above problems of the conventional technology, and its object is to improve the storage efficiency of the gas generating agent and improve the pressure resistance of the pressure vessel. It is intended to provide a gas generator for an airbag.

[Means for solving the problem]

In order to achieve the above object, a gas generator for an airbag according to the present invention divides a cylindrical container into a central portion, an intermediate portion and an outer peripheral portion, accommodates an ignition means in the central portion, and a gas generating agent in the outer peripheral portion. Is provided, a radial passage extending from the central portion to the outer peripheral portion is provided, and the passage is filled with the transfer charge, and a gas hole is opened in a section between the outer peripheral portion and the intermediate portion to discharge gas from the intermediate portion.

[Action]

Since the gas generating agent is stored in the outer peripheral portion, the storage space is effectively utilized. Further, since the radial passage extending from the central portion to the outer peripheral portion is provided and the passage is filled with the transfer charge, there is no problem in the chemical reaction of the gas generating agent in the outer peripheral portion by the ignition means in the central portion. Further, since gas holes are opened in the partition between the outer peripheral portion and the intermediate portion to allow gas to be released from the intermediate portion, the space in the intermediate portion is effectively utilized and the outer peripheral wall of the cylindrical container has no gas holes.

〔Example〕

Hereinafter, embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is a sectional view of a gas generator for an air bag of the present invention,
2 is a sectional view taken along the line AA of FIG. 1, FIG. 3 is a partial sectional view showing another structure of the intermediate portion, FIG. 4 is a sectional view taken along the line BB of FIG. 3, and FIG. It is sectional drawing of the airbag safety apparatus which uses a gas generator.

First, the configuration of an airbag safety device using a gas generator will be described with reference to FIG. The airbag safety device 1 is
Gas generator 4 and airbag 5 in base 2 and cover 3
Are integrated with each other and are fixed by bolts 6 to form a part of the handle 7. Therefore, in appearance, it is not necessary to be aware that the airbag safety device 1 is present there. As the mounting position of such an airbag safety device, in addition to the handle 7, there are a lid of a small-sized box in front of the front passenger seat, a back plate of a backrest of a front seat, and the like. The airbag 5 is inflated like a balloon at the time of a collision and serves as a cushioning material between the handle and the like, and is normally folded small and stored in the cover 3. The air bag 5 and the base 2 are airtightly attached, and the gas generator 4 is provided in an airtight space between the air bag 5 and the base 2. Further, the cover 3 is provided with a notch or a thin portion so that it can be deployed (opened) when the airbag 5 is inflated.

Next, the gas generator for an air bag of the present invention will be described with reference to FIGS. 1 and 2. The external appearance of this gas generator is a cylindrical container 10, and this cylindrical container 10 comprises an upper container 11 and a lower container 12. The upper container 11 includes an outer peripheral wall 13 and an intermediate wall 14
And a small cylinder having an inner peripheral wall 15 is connected to each other by a radial passage 16 having a space around it. The lower container 12 has a lid shape, and the both are integrated by pressure welding or welding to form a central portion 17, an intermediate portion 18, and an outer peripheral portion 19. Further, the inner peripheral wall 15 and the radial passage 16 are lower than the outer peripheral wall 13, and a recess 20 is formed on the upper surface of the cylindrical container 10. Then, in the central portion 17, an electric heater 21 that operates by receiving a current supply through a collision sensor (not shown),
An ignition charge 22 that covers the electric heater 21 is stored. The electric heater 21 and the ignition charge 22 form an ignition means.
The intermediate portion 18 includes a spiral blade 23 provided on the outer periphery of the inner peripheral wall 15 and a spiral blade 24 provided on the inner periphery of the intermediate wall 14, and a coolant 25 wound around the outer periphery of the inner peripheral wall 15 and the inner periphery of the intermediate wall 14. It is stored. A gas generating agent 26 is stored above the outer peripheral portion 19, and a coolant 27 is attached to a portion below the outer peripheral portion 19 facing the gas hole 19A. And the radial passage
The transfer charge 30 is filled in the inside of the space 16, and the ignition charge 22 in the central part 17 and the gas generating agent 26 in the outer peripheral part 19 are thermally connected. Also,
A gas hole is formed in the intermediate wall 14 which is a partition between the outer peripheral portion 19 and the intermediate portion 18.
14A is open. Furthermore, the concave portion 20 at the top of the cylindrical container 10
A filter assembly 28 is mounted on the cylindrical container 10 and is fixed to the cylindrical container 10 by a ring 29.

3 and 4 show another structure of the intermediate portion.
Gas holes 14A are opened obliquely in the circumferential direction below the intermediate wall 14, and an inclined plate 31 in the same direction is provided at the outlet of the gas holes 14A.
A coolant 32 is wound around the lower part of 15. Furthermore, three spiral blades 33 are provided on the outer periphery of the inner peripheral wall 15 and the intermediate wall 14
Coolant 34 is attached to the inner circumference. In this way, the swirling gas flow is easily formed to enhance the cooling efficiency.

Next, the operation of the air bag gas generator having the above-described configuration will be described with reference to FIGS. 1 and 2. The hot air of the ignition charge 22 ignited by the electric heater 21 flows into the outer peripheral portion 19 via the transfer charge 30. The hot air causes the gas generating agent 26 to undergo a chemical reaction to be gasified. This gas flow has gas holes 19A and 1A.
It passes through 4A and reaches the middle section 18. On the way, it is cooled by the coolant 27. Next, a spiral flow is formed by the spiral wings 23, 24,
Further cooled by the coolant 25, dust is taken by the filter assembly 28 through the space between the radial passages 16 and jetted from the upper surface of the cylindrical container 10. That is, since the gas generating agent 26 is housed in the outer peripheral portion 19, the volume is larger than the ratio of the thickness W1 thereof, and the amount of the gas generating agent 26 can be increased. On the other hand, the thickness W2 of the intermediate portion can be secured, and the spiral blades 23, 24 for forming the swirling flow of the gas flow and the coolant 25 for cooling the gas flow can be arranged.
The area of the filter assembly 28 is also comparable to that of the conventional one. Further, since the outer peripheral wall 13 has no gas holes, the pressure resistance of the cylindrical container 10 is increased.

In the above description, the case where the collision sensor is located outside the gas generator 10 has been described, but the central portion 17 of the gas generator 10 is described.
A collision sensor can also be housed inside.

[Effect of device]

A gas generator for an air bag according to the present invention divides a cylindrical container into a central part, an intermediate part and an outer peripheral part, and stores an ignition means in the central part, a gas generating agent in the outer peripheral part, and an outer peripheral part from the central part. Is provided with a radial passage leading to a portion, and the passage is filled with transfer charge, and a gas hole is opened in a section between an outer peripheral portion and a central portion to release gas from an intermediate portion. A gas generating agent is stored in the outer peripheral portion. Since it allows gas to be released from the middle part,
The storage space for the gas generating agent is effectively used, and the amount of the gas generating agent can be increased without increasing the outer diameter of the gas generator. Furthermore, since there are no gas holes in the outer peripheral wall of the gas generator, the pressure resistance of the cylindrical container is increased, and the wall thickness can be reduced.

[Brief description of drawings]

FIG. 1 is a sectional view of a gas generator for an airbag of the present invention, FIG. 2 is a sectional view taken along the line AA of FIG. 1, and FIG. 3 is a partial sectional view showing another structure of an intermediate portion. The drawing is a sectional view taken along the line BB in FIG. 3, FIG. 5 is a sectional view of an airbag safety device using a gas generator, and FIG. 6 is a sectional view of a conventional airbag gas generator. 4 ... Gas generator, 10 ... Cylindrical container, 14A ... Gas hole, 1
6 ... Radial passage, 17 ... Inner circumference, 18 ... Middle section, 19 ...
... outer peripheral part, 21 ... electric heater, 22 ... ignition agent (ignition means), 26 ... gas generating agent, 30 ... transfer agent.

Claims (1)

[Scope of utility model registration request] 1. A cylindrical container is divided into a central portion, an intermediate portion and an outer peripheral portion, an ignition means is stored in the central portion, a gas generating agent is stored in the outer peripheral portion, and a radial passage extending from the central portion to the outer peripheral portion is formed. A gas generator for an air bag, characterized in that the passage is filled with a transfer charge, and a gas hole is opened in a section between an outer peripheral portion and an intermediate portion to release gas from the intermediate portion.