JP3114257B2 - Shock absorber - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a shock absorbing device for absorbing a shock applied to a driver or an occupant by inflating a bag for protecting a human body at the time of a collision of an automobile or the like.

[0002]

2. Description of the Related Art As shown in FIG. 4, an inflator conventionally used in an airbag system for an automobile includes an alkali metal azide and a metal oxide in a case 21 having a gas discharge hole 22 formed on an outer wall thereof. A gas generating agent 23 comprising a mixture;
An ignition device 24 is housed, and the ignition device 24 has a structure formed of an ignition agent 25 made of an explosive substance such as an explosive and an igniter 26 operated by a shock detection signal. Ignition agent 2
5 is ignited, and the explosive thermal energy burns the gas generating agent 23 to generate gas.

[0003]

However, the explosive substance used in the igniting agent 25 has a problem in safety in storage and assembling work because handling is dangerous. Further, since the explosive substance can be obtained by anyone in a state where the explosive substance is mounted on a car, protection of the explosive substance is a serious problem.

The conventional gas generating agent 23 using an alkali metal azide is 4NaN ₃ + O ₂ → 2Na ₂ O + 6.
Nitrogen gas is generated by the reaction formula of N ₂ , but Na ₂ O, a by-product, has extremely harmful properties to the human body. is there.

In view of the above, the present invention aims to provide a device capable of effectively absorbing impact by inflating a bag without using a gas containing an explosive substance or a harmful component, instead of the above-described airbag device. Is what you do.

[0006]

To solve the above object, according to an aspect of this inventions comprises a reservoir of vaporizable material, the gas generation container provided with a heating element to be connected to the heating power source, can expand and contract Connected to the gas generating container, and
Exothermic substance that generates heat by thermal decomposition is provided at the connection with the
It was .

[0007] As the above evaporative substance, 50 ° C to 15 ° C
Those having a boiling point of 0 ° C. are desirable, and water or alcohol can be used.

[0008]

As the exothermic substance, a mixture of iron oxide and carbon can be used. The exothermic substance is desirably used in a powdered solid state.

[0010] In addition, bags of top Symbol is to form a heat insulating material
Is good.

In addition, an electric double layer capacitor can be used as a heating power supply.

[0012]

[Action] is generating heat by energization of the heating element by the detection signal of the shock, by heating the evaporation material to inflate the bag by vaporization gas generated.

[0013] Since such a vaporized gas is not a reaction gas generated by a thermal decomposition reaction, no toxic components are generated, and even if the vaporized gas flows out, it does not harm the human body. Further, since the heating element is operated by energization, there is no danger as in the case of using an explosive substance. In addition, since heat is instantaneously generated by operating a switch or the like, highly responsive gas can be generated.

Further, the boiling point of the above-mentioned evaporative substance is 50 ° C. to 1
When the temperature is in the range of 50 ° C., there is no inconvenience that vaporization starts carelessly due to an increase in the surrounding temperature, and the surface temperature of the bag does not become too high due to the vaporized gas.
It is possible to prevent human body burn accidents.

Further, when the vaporized gas from the gas generation container is introduced into the bag, with its vaporized gas, pyrogens are released into the bag, and pyrolysis heating the bag by the heat of the vaporized gas. Thereby, the internal temperature of the bag can be maintained at the boiling point or higher, and liquefaction of the vaporized gas introduced into the bag can be prevented.

When such a heat-generating substance is used in a powder state, it can be widely dispersed in the bag by the pressure of the vaporized gas released into the bag, and the inside thereof can be uniformly heated.

Meanwhile, by forming the bus Tsu grayed with a heat insulating material, it is possible to maintain the outer surface of the bag at a low temperature with respect to the bag interior formed of a high temperature condition, it is possible to prevent the human body burns by contact.

As a power source for heating, a normal power source such as a battery or a capacitor can be used.
By using an electric double-layer capacitor, it is possible to hold a large amount of electricity in a lightweight and compact state, and to obtain a compact device and high heating performance by allowing a large current to flow through the heating element at a time. it can.

[0019]

1 and 2 show an impact absorbing device according to an embodiment. In this shock absorbing device, as shown in FIG. 1, a gas generating container 1 and an inflating and contracting bag 2 are connected by a communication pipe 3, and inside the communication pipe 3, fine dust and the like in the gas are removed. The filter 4 is housed.

As shown in FIG. 2, the gas generating container 1 has six metal films 6, 7, 8, 9, 10, which are large enough to cover the inner surface of the container constituting the heating element 5. , 11
Each is installed in parallel at a fixed interval,
The upper side of the uppermost metal film 6 serves as a reservoir 13 for the evaporable substance 12.

Each of the metal films 6 to 11 is formed of a material that can be melted by energization, and is set so as to become thinner in order as the thickness increases. 14 are connected in parallel.

The power supply circuit 14 includes an electric double layer capacitor 15 and a switch 16. The switch 16 is connected to an impact detector (not shown) for detecting a pressure change at the time of collision. It is set so as to operate in response to a signal from and connect the capacitor 15 to each metal film.

The bag 2 is made of heat-insulating SiC or Al.
It is formed by knitting a ceramic fiber such as ₂ O ₃ into a bag shape, and has a flexibility to expand by a gas pressure from the inside.

The filter 4 inside the communication pipe 3 is filled with a powder of the exothermic substance 17.

In the shock absorbing device having the above structure, when a current is supplied from the capacitor 15 to each metal film by the operation of the switch 16, the metal films 6 to 11 are melted in order from the thinner one due to the difference in thickness. Then, the evaporative substance 12 stored on the upper side is dropped while being heated by the heat of fusion.

The vaporized gas generated by this heating is introduced into the bag 2 through the filter due to the increase in the pressure inside the container 1, and at this time, the iron oxide and carbon powder inside the filter 4 are removed together with the vaporized gas into the bag 2. And is decomposed by the heat of the vaporized gas inside the bag 2 to heat the inside of the bag 2.

The bag 2 is maintained at a temperature equal to or higher than the boiling point by the heating, and is expanded by the introduced gas.

(Experimental Example) Next, a description will be given of a bag inflation experiment performed using the above-described shock absorbing device. In this experiment, the inner dimensions of the gas generating vessel 1 were set to a height of 15 mm and a width of 5 mm.
0 mm, length 50 mm, and evaporable substance 12
The filter 4 was filled with a mixture of copper oxide and carbon powder as the exothermic substance 17.

Aluminum metal is used for each of the metal films 6 to 11, and the thickness of the metal films is 2.5, 3.
Formed at 0, 3.5, 4.0, 4.5, 5.0 μm. The distance between the metal films was set to 3 mm.

Further, the capacity of the electric double layer capacitor 15 was set such that a current of 4 A flowed through each of the metal films 6 to 11, and the capacity of the bag 2 was set to 30 liters.

The experiment was performed by applying a simulated shock to the shock detector and operating the switch 16 in the above structure. Simultaneously with the operation of the switch 16, the uppermost metal film 6 began to melt, and then the lower metal film was melted in order, and water was vaporized and dropped along with it. Then, when the lowermost metal film 11 was melted, the water was completely evaporated to become steam, and the bag 2 was rapidly expanded.

FIG. 3 shows a change in pressure and a change in temperature inside the bag 2 in the inflation experiment with the lapse of time from the operation of the switch 16. As shown in this figure, the pressure in the bag shows the maximum pressure (two vaporizations) around 30 msec, and shows that the bag has expanded to a completely expanded shape around 60 msec.

After the temperature in the bag rises to the maximum temperature around 40 msec, the boiling point temperature of water (100
° C) or higher, indicating that the iron oxide and carbon powder generated heat inside the bag and effectively maintained the temperature.

When the temperature of the outer surface of the bag 2 after inflation was measured, it was found to be around 37 ° C., and no adverse effects such as burns occurred.

Further, when the gas inside the bag 2 was analyzed, it was confirmed that the bag had been inflated by water vapor, and no harmful components were contained.

Although water is used as the evaporative substance in the above experimental example, the present invention is not limited to this, and alcohol and other evaporative substances can be used.

Further, the type of the exothermic substance and the structure for vaporizing the evaporative substance are not limited to those of the above-described embodiment.

[0038]

As described above, according to the present invention, since the bag is inflated by using the vaporized gas of the evaporating substance, it is possible to realize a safe shock absorbing structure without generation or outflow of harmful gas.

Further, since the evaporative substance is vaporized by heating by energization, there is no danger as in the case of burning an explosive substance such as an explosive, and an apparatus excellent in safety can be provided.

[Brief description of the drawings]

FIG. 1 is a partially longitudinal sectional front view showing an impact absorbing device of an embodiment.

FIG. 2 is a longitudinal sectional front view showing the internal structure of the above-described inflator.

FIG. 3 is a graph showing a pressure change and a temperature change inside the airbag during gas introduction.

FIG. 4 is a sectional view showing the internal structure of a conventional inflator.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Gas generating container 2 Bag 4 Filter 6, 7, 8, 9, 10, 11 Metal film 12 Evaporable substance 13 Storage part 14 Power supply circuit 17 Heat generating substance

────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Yoshihiro Nakai 1-3-1 Shimaya, Konohana-ku, Osaka City Osaka Works, Sumitomo Electric Industries, Ltd. (56) References JP-A-62-6849 (JP, A) JP-A-61-235247 (JP, A) JP-A-3-79451 (JP, A) JP-A-48-57565 (JP, U) (58) Fields investigated (Int. Cl. ⁷ , DB name) B60R 21 / 16-21/32 B01J 7/00

Claims (7)

(57) [Claims] And 1. A reservoir of evaporable substances, the gas generation container provided with a heating element to be connected to the heating power source, and connecting the inflatable collapsible bag further the gas generation container and bag
Shock-absorbing device provided with a heat-generating substance that generates heat by thermal decomposition at the connection portion with the heat- absorbing material . 2. The shock absorbing device according to claim 1, wherein the evaporable substance has a boiling point of 50 ° C. to 150 ° C. 3. The shock absorbing device according to claim 2, wherein the evaporative substance is water or alcohol. 4. The shock absorbing device according to claim 1, wherein said exothermic substance is a mixture of iron oxide and carbon. 5. The shock absorbing device according to claim 1, wherein the exothermic substance is a powdery solid. 6. The shock absorbing device according to claim 1, wherein said bag is formed of a heat insulating material. 7. The heating power impact absorbing device according to any one of claims 1 to 6 is an electric double layer capacitor.