JP3607215B2 - Method for inflating a vehicle occupant restraint - Google Patents

Description

[0001]
Related applications
This application is filed by Jack L. Blumenthal and Nahum Gat and has been assigned the title “Inflatable Vehicle Passenger Restraint” No. 07 / 761,685. Is a continuation-in-part application. It has the benefit of the earlier filing date of said application 07 / 761,685 and is claimed by this document.
[0002]
Field of Invention
The present invention relates to a new and improved method of inflating an inflator, such as a vehicle occupant restraint.
[0003]
Background of the Invention
Known structures for inflating vehicle occupant restraints are disclosed in U.S. Pat. Nos. 3,806,153, 3,868,124 and 3,895,821. In each of the structures disclosed in these patents, air, or other gas, and solid material that produces the gas is stored in a container. When the vehicle decelerates, indicating a collision, the gas in the container is released, inflating the vehicle occupant restraint that restrains the vehicle occupant during the collision. In addition, when a rapid deceleration of the vehicle indicating a collision occurs, the gas-producing substance is ignited. As the gas-producing substance burns, it forms a hot gas or vapor that heats and mixes with the stored gas, and the heated mixture of gas flows into the vehicle occupant restraint.
[0004]
Summary of the Invention
The present invention relates to a method for inflating an inflating inflator, such as an occupant restraint. A method for inflating a vehicle occupant restraint according to the present invention includes storing a first gas in a first chamber and a second gas comprising a combustible gas mixture in the second chamber. Storing, releasing the first and second gases at different times and flowing from the first and second chambers at the different times, and the first gas being in the first chamber Igniting the combustible gas mixture after being released from the vehicle, and sending the first gas and the ignited combustible gas mixture into the vehicle occupant restraint.
[0005]
Preferably, the gas mixture comprises an inert gas, a combustible gas and an oxidant gas. The inert gas is preferably nitrogen or argon or a mixture of nitrogen and argon. The fuel gas is preferably hydrogen or methane or a mixture of hydrogen and methane, but may be some other combustible gas. The oxidant gas is preferably oxygen. The inert gas can be removed and instead a fuel-poor combustible gas mixture can be used. A small amount of an inert tracer gas, such as helium, can also be added to assist in the device gas leak investigation.
[0006]
The containing means can take a variety of different forms. In one aspect of the invention, the containing means is a single container for containing an inert gas, a fuel gas, and an oxidant gas as a gas mixture. Alternatively, a single container can contain a very fuel-poor mixture of combustible gases.
[0007]
In other embodiments, the primary container contains fuel gas, the secondary container contains oxidant gas, and the containing means receives the fuel gas and oxidant gas and ignites the gas mixture therein. Define a combustion chamber. In this embodiment, the amount of oxidant gas used exceeds the stoichiometric amount to support the combustion of the fuel gas.
[0008]
In accordance with the present invention, the inflation rate of the inflator can be controlled by providing the desired volume of the inflator at a given time after ignition of the fuel gas. The inflation rate of the inflator and the pressure in the inflator are the amounts of fuel gas and oxidant gas to obtain the desired combustion rate that will continue to determine the predetermined volumetric flow rate of the warm gas into the inflator. Can be controlled by selecting. Alternatively or additionally, the inflation rate can be controlled by a flow control orifice or the like through which gas flows into the inflator. Another technique for controlling the time required for expansion is to change the number of locations in the containing means where the fuel gas is ignited.
[0009]
An improved ignition means provides for igniting a mixture of gases. The ignition means can be used to transfer energy through the unperforated wall portion of the containment means. The energy transmitted through the non-perforated wall portion of the containing means results in ignition of the igniting material in the containing means. In particular, an ignition charge located near the outside of the non-perforated wall portion of the containing means ignites so as to cause ignition of an ignition charge located near the inside of the non-perforated wall portion of the containing means. It's easy to do. According to another feature of the ignition means, an extended central part in the fragile sheath is arranged in the containing means. The extended central part is ignited as a result of the shattering of the sheath and the glowing reaction product blowing out into the containing means.
[0010]
【Example】
(Example 1)
The present invention can be embodied by many different structures. As a representative, the present invention embodied in the passenger safety device 10 is illustrated in FIG. The occupant safety device 10 includes an inflatable occupant restraint device 12 and a device for inflating the occupant restraint device.
[0011]
When a vehicle suddenly decelerates, indicating a vehicle collision, the occupant moves to a certain part of the vehicle (handle, instrument panel, etc.) and hits the part vigorously when the vehicle collides. The restraining device 12 swells and is located between the passenger in the vehicle and its components. The inflated occupant restraint device 12 absorbs the kinetic energy of the occupant's movement and stops the occupant's movement, so that the occupant does not hit the vehicle parts vigorously. Such an occupant restraint device can be inflated with various gases. Regardless of the gas used for the occupant restraint device 12, the occupant restraint device is commonly referred to as an air bag.
[0012]
The occupant restraint device 12 is inflated by flowing gas from the container 14. The container 14 has a gas chamber 16 into which a gas mixture 18 is placed. The gas mixture 18 preferably includes a fuel gas, an oxidizing gas that burns the fuel gas, and an inert gas. The inert gas is preferably nitrogen, argon or a mixture of nitrogen and argon. The oxidizing gas is preferably oxygen. The fuel gas is preferably hydrogen, but may be methane or a mixture of hydrogen and methane.
[0013]
Alternatively, the gas mixture in the container 14 may be a mixture of oxidizing gas and fuel gas, where the fuel gas is very thin and the amount of oxidizing gas is in excess of that required to burn the fuel gas. Good.
[0014]
The gas mixture 18 in the container 14 burns easily upon ignition, but is otherwise not explosive. The gas mixture 18 can have various compositions. The fuel gas of the gas mixture 18 is 2 to 16 mol%. The oxidizing gas is 7 to 98 mol% of the gas mixture 18. The balance is an inert gas and is 0 to 91 mol% of the gas mixture 18. Preferably, the gas mixture 18 comprises 10-14 mol% hydrogen, 15-25 mol% oxygen and 61-75 mol% inert gas.
[0015]
The gas mixture 18 in the container 14 is normally under pressure. The pressure depends on the capacity of the occupant restraint device 12 to be inflated, the time required to inflate, the desired inflation pressure, the capacity of the container of the gas mixture 18, and the proportion of each gas in the gas mixture. Typically, the gas mixture 18 in the container 14 is about 344.70 × 10⁴To about 3447.0 × 10⁴Pascal (500-5,000 psi). Preferably, the gas mixture 18 in the container 14 is about 689.40 × 10⁴To about 2068.20 × 10⁴Pascal (1,000-3,000 psi). However, the present invention can use any gas mixture regardless of pressure.
[0016]
In one embodiment of the invention, the gas mixture 18 consists of dry air and hydrogen. The mixture of dry air and hydrogen ranges from 86 mole% air and 14 mole% hydrogen to 92 mole% air and 8 mole% hydrogen. However, here, the range of 90 mol% air and 10 mol% hydrogen to 87 mol% air and 13 mol% hydrogen is preferred.
[0017]
When the vehicle suddenly decelerates, a deceleration sensor 22 (which can be of any well-known suitable structure) activates an ignition device 24 in the gas chamber 16 and the fuel gas in the gas mixture 18 ignites. Since the oxidizing gas exists, the fuel gas burns. As the fuel gas is combusted, the gas is warmed by the heat generated by the combustion of the fuel gas, and additional gas and steam are generated by the combustion of the fuel gas, so the pressure in the gas chamber 16 increases. After the elapse of a predetermined time or when the pressure in the gas chamber 16 reaches a predetermined value, the end wall 28 of the container 14 is ruptured, and warm gas flows to the occupant restraint device 12 through the flow control port. . When the gas flows into the occupant restraint device 12, the occupant restraint device 12 is inflated by the gas and placed in a predetermined position for restraining the occupant.
[0018]
If the amount of hydrogen is about 8 mol% or less, it will be difficult to ignite the hydrogen. When the amount of hydrogen is 14 mol% or more, unacceptable pressure and / or temperature is generated in the occupant restraint device 12. Preferably, the gas mixture 18 includes an amount of fuel gas that is sufficiently consumed by combustion in the vessel 14. Accordingly, the occupant restraint device 12 is left with an inert gas, a combustion product and a remaining oxidizing gas when an inert gas is used, or when an inert gas is not used. It swells almost exclusively by the oxidation gas and combustion products.
[0019]
As the gas flows from the container 14 into the occupant restraint device 12, the gas expands and cools. Further, as the occupant restraint device swells, air from around the safety device 10 is sucked into the occupant restraint device 12. This sucked air also cools the gas in the occupant restraint device 12.
[0020]
The fuel gas in the gas mixture 18 burns to generate heat and raises the pressure of the gas in the gas chamber 16, so that the occupant restraint device 12 is inflated into the container 14 to the desired pressure. The total volume of gas that must be stored can be minimized.
[0021]
Further, when the fuel gas burns, a gaseous substance, that is, water vapor is generated instead of a solid substance, so that a particulate filter or the like is not necessary.
[0022]
The container 14 in the safety device 10 is shown in detail in FIG. As shown in FIG. 4, the container 14 has a cylindrical tank 30. The tank 30 defines a chamber 16 that contains a mixture 18 of gases. The tank 30 must be made of a material that is impermeable to the gas contained in the container. Accordingly, the tank 30 can be made of a suitable material such as steel or aluminum and may have a glass lining. A cylindrical gas flow diffuser 32 encloses the tank 30. The diffuser 32 has a number of gas flow openings 35.
[0023]
The igniter housing 34 extends through an opening at one end of the tank 30 and supports the igniter 24. The ignition device 24 may be any type of many known types of ignition devices. Thus, the igniter may be a spark plug, a flash valve igniter (such as that shown in US Pat. No. 3,695,179), or a pyrotechnic igniter. The particular igniter 24 shown in FIG. 4 is a known squib containing a pyrotechnic material, preferably zirconium potassium perchlorate. A single ignition device as shown in FIG. 4 or a plurality of ignition devices can be used. The proportion of the fuel gas in the gas mixture 18 can be varied to facilitate ignition of the fuel gas by one or more igniters.
[0024]
A cylindrical manifold 40 extends through an opening at the end of the tank 30 opposite the igniter 24 and likewise extends through an adjacent opening in the diffuser 32. The circular end wall portion 42 of the manifold 40 disposed inside the tank 30 has a control orifice 44 disposed at the center. The cylindrical side wall 46 of the manifold 40 has gas flow openings 48 arranged between the tank 30 and the diffuser 32 and arranged circumferentially. The end wall 28 schematically shown in FIG. 1 is a rupture disc supported within the manifold 40 between the control orifice 44 and the gas flow opening 48.
[0025]
When the fuel gas in the gas mixture 18 in the chamber 16 is ignited by the igniter 24, the combustion of the fuel gas produces heat and gaseous combustion products that increase the pressure in the chamber 16. When the increased pressure in the tank 30 reaches a predetermined level, the end wall portion 28 bursts. The pressurized gas then flows through the manifold 40 from the chamber 16 to the gas flow opening 35 of the diffuser 32 and through the gas flow opening 35 into the vehicle occupant restraint 12.
[0026]
FIG. 5 is a graph showing the relationship between the pressure in the chamber 16 and the gas volume in the vehicle occupant restraint device 12 during operation of the vehicle occupant safety device 10. The pressure in the chamber 16 is indicated by the curve P in FIG. The scale for curve P is shown on the left side of FIG. The volume of gas in the vehicle occupant restraint device 12 is shown by the curve V in FIG. The scale for curve V is shown on the right side of FIG. Time T₀, The fuel gas in the gas mixture 18 in the chamber 16 is ignited and the pressure in the chamber 16 as a result of combustion is reduced to the storage pressure P_SBegin to rise beyond. Time T₁, The end wall 28 ruptures and the pressurized gas begins to flow into the vehicle occupant restraint device 12. Next, as indicated by curve V, the volume of gas in the vehicle occupant restraint device 12 begins to rise. As the combustion process continues to generate heat, this causes the gas mixture to expand at a faster rate than the gas flow that flows through the orifice 44 into the vehicle occupant restraint 12 so that the pressure in the chamber 16 is increased by the end wall After the part is opened, it is initially kept constant or continues to rise. As the combustion approaches completion, the pressure in the chamber 16 decreases as the pressurized gas moves from the chamber 16 into the vehicle occupant restraint device 12. As the pressure in the chamber 16 decreases, the volume of gas in the vehicle occupant restraint device 12 increases until the vehicle occupant restraint device 12 is fully inflated for the purpose of restraining the vehicle occupant.
[0027]
FIG. 5 simply shows an example of the operation of the vehicle occupant restraint inflation device of the present invention. The curve in FIG. 5 can be varied in a number of ways to vary the capacity versus time curve, and the expansion of the vehicle occupant restraint system can be tailored for a particular application for a particular vehicle. For example, reducing the time to fully inflate the vehicle occupant restraint 12 by increasing the fuel gas content of the gas mixture 18 and / or by increasing the oxidant gas content. be able to. Furthermore, the number of locations where the fuel gas in the gas mixture 18 is ignited and / or the area of the control orifice 44 can be increased. Further, by combining these changes, the time for inflating the vehicle occupant restraint device 12 can be reduced. Conversely, the time to fully inflate the vehicle occupant restraint 12 can be increased, for example, by reducing the fuel gas content and / or oxidant gas content in the gas mixture 18.
[0028]
Embodiment I described above is a preferred embodiment of the present invention. In the following, another embodiment of the present invention, which is another method for carrying out the present invention, will be described.
[0029]
(Example 2)
Since the embodiment of the invention shown in FIG. 2 is generally the same as that shown in FIG. 1, the same reference numerals will be used to represent the same parts. Note that the subscript a is used together with a symbol to represent the member shown in FIG. 2 in order to avoid confusion.
[0030]
The passenger car safety device 10a (FIG. 2) includes an inflatable passenger restraint 12a. The restraint is expanded by the gas flow from the container 14a. The container 14a has a chamber 16a. A gas mixture 18a is held in the chamber. Similar to the gas mixture 18, the gas mixture 18a includes a fuel gas, an oxidizing gas to support the combustion of the fuel gas, and an inert gas. As another aspect, the gas mixture 18a may be a combustible gas mixture that includes fuel gas and oxidizing gas and has very little fuel. The gas mixture 18a may be under pressure.
[0031]
When the passenger vehicle decelerates quickly, the decelerating sensor 22a activates the opening device 60 to mechanically puncture the end wall 28a of the container 14a. The opening device 60 consists of a piston. The piston moves against the end wall 28a by an explosive charge. Preferably, at the same time, deceleration sensor 22a activates igniter 24a to ignite the fuel in gas mixture 18a. Thus, in the embodiment of the present invention shown in FIG. 2, the container 14a is opened by the opening device 60 and at the same time the fuel in the gas mixture 18a is ignited by the igniter 24a. In another aspect, the gas mixture 18a may be ignited shortly after the end wall 28a is pierced. This is to send a slightly "soft" or slow initial gas flow into the occupant restraint 12a. In addition, the gas mixture 18a may be ignited before the end wall 28a is pierced. When the fuel gas burns, the gas in the chamber 16a is heated. The heated gas flows from the chamber 16a through the opening of the end wall 28a and into the occupant restraint 12a. As a result, the occupant restraint 12a expands.
[0032]
The gas mixture 18a can be many different compositions. A preferred composition of the gas mixture 18a is the same as that of the gas 18 described above. According to one specific embodiment, the gas mixture 18a includes dry air. Approximately 11 mol% hydrogen gas is added to the dry air as a fuel gas. Before the end wall 28a of the container 16a is pierced by the opening device 60 and before the hydrogen gas in the gas mixture 18a is ignited, the pressure of the gas mixture 18a held in the container 14a is approximately 2 , 000 psi. The pressure during storage of the gas mixture 18a is preferably the same as that of the gas mixture 18 described above.
[0033]
(Example 3)
A third embodiment of the present invention is shown in FIG. The embodiment of the invention shown in FIG. 3 is generally the same as that shown in FIGS. 1 and 2, and so the same reference numerals will be used to represent the same members. Note that the subscript b is used together with a symbol to represent the member shown in FIG. 3 in order to avoid confusion.
[0034]
The passenger car safety device 10b (FIG. 3) includes a passenger restraint 12b. The restraint is inflated by the gas flow from the container 14b and restrains the movement of the occupant. The container 14b includes a first chamber or upper compartment 70 and a second chamber or lower compartment 72. The upper compartment 70 has an end wall 28b. Upper and lower compartments 70 and 72 are separated from each other by an intermediate wall 74. The upper compartment 70 contains an inflatable gas, ie a pressurized gas 78. The pressurized gas is not flammable. The lower compartment contains a combustible gas, ie a pressurized gas mixture 80. The gas mixture 80 preferably includes a fuel gas, an oxidizing gas to support combustion of the fuel gas in the gas mixture, and an inert gas. In another aspect, the gas mixture 80 may consist of oxidizing gas and fuel gas. In this case, the gas mixture 80 is a gas mixture with very little fuel.
[0035]
When the passenger car suddenly decelerates, the deceleration sensor 22b actuates the opening device 60b and mechanically punctures the end wall 28b of the container. Since the gas 78 in the upper compartment 70 is under pressure, the gas 78 flows from the upper compartment 70 into the occupant restraint 12b when a hole is drilled in the end wall 28b of the container.
[0036]
As gas 78 flows from upper compartment 70 into occupant restraint 12b, the pressure in upper compartment 70 decreases. Accordingly, the pressure difference between the gas mixture 80 in the lower compartment 72 and the gas 78 in the upper compartment 70 increases. When the gas pressure difference in the upper and lower compartments 70 and 72 reaches a predetermined pressure difference, the intermediate wall 74 is ruptured and the lower compartment 72 and the upper compartment 70 are connected by a fluid path. As a result, the lower compartment 72 is connected to the occupant restraint 12b through the upper compartment by the fluid path.
[0037]
Whether or not the intermediate wall 74 is ruptured due to the pressure difference is detected by the sensor 86. In another aspect, sensor 86 detects whether intermediate wall 74 has deviated from a preset position. When sensor 86 detects that intermediate wall 74 has ruptured or deviated from a preset position, sensor 86 activates igniter 88 and ignites the fuel gas in gas mixture 80. As the fuel gas in the gas mixture 80 is ignited and burned, the gas in the lower compartment 72 is heated. As the gas in the lower compartment 72 is heated, the pressure in the lower compartment 72 increases. Therefore, the gas velocity flowing through the intermediate wall 74 and the end wall 28b and reaching the occupant restraint 12b increases, and the gas volume effective to inflate the occupant restraint 12b also increases.
[0038]
The upper compartment 70 has a pressure of about 1338.8 × 10⁴Pascal (2,000 psi) dry air may be filled. The gas mixture in the lower compartment 72 can have different compositions and different pressures. The lower compartment 72 has a pressure of about 1338.8 × 10⁴It may be filled with a gas mixture of Pascal (2,000 psi). The gas mixture 80 in the lower compartment 72 may consist of 85-90 mol% dry air and 10-15 mol% hydrogen gas. The upper compartment 70 is filled with nitrogen gas, and the lower compartment may be filled with a mixture containing nitrogen gas, hydrogen gas and oxidizing gas. The gas mixture in the lower compartment 72 can have any composition and / or storage pressure for the gas mixture 18 described in the embodiment shown in FIG.
[0039]
When the pressure difference between the upper and lower compartments 70 and 72 reaches a predetermined value, the intermediate wall 74 ruptures, and the lower compartment 72 and the upper compartment and occupant restraint 12b are connected by a fluid path. Preferably, the upper compartment 70 and the lower compartment 72 of the container 14b can be connected by different ways of fluid paths. For example, the intermediate wall 74 can be mechanically punctured by an opener similar to the opener 60b. The operation of activating the opening device to make a hole in the intermediate wall 74 and simultaneously igniting the fuel gas in the gas mixture by operating the igniter is performed after the deceleration sensor 22b detects a sudden deceleration of the passenger car in advance. It is done when the time interval that has been decided has passed.
[0040]
(Example 4)
A fourth embodiment of the present invention is shown in FIG. In this embodiment, hydrogen is stored in a state where pressure is applied to the container 100, and oxygen is stored in a state where pressure is applied to the container 101. The vessel 100 is provided with an outlet 102 in communication with a combustion chamber 104 delimited by containment means 106. Similarly, the vessel 101 is also provided with an outlet 108 in communication with the combustion chamber 104.
[0041]
The outlet 102 is also provided with a flow control orifice 110 and a rupture disk 112. When the rupture disc 112 is opened, hydrogen flows into the combustion chamber 104 of the containing means 106. The hydrogen flow is partially controlled near the area of the flow control orifice 110. The outlet 108 is provided with a flow control orifice 114 and a rupture disc 116. When the rupture disc 116 is opened, oxygen flows into the combustion chamber 104 of the containment means 106. The oxygen flow is partially controlled near the area of the flow control orifice 114. Thus, when the rupture discs 112, 116 are opened, gas, ie hydrogen and oxygen, is contained in the containment means 106 and a combustible mixture of hydrogen and oxygen is formed.
[0042]
A suitable ignition device 130 is associated with the containment means 106. When the ignition device 130 is activated, the gas mixture in the combustion chamber 104 of the containment means 106 ignites, increasing the pressure in the combustion chamber 104 and warming the gas. Gas travels from the combustion chamber 104 through the flow control orifice 131 and the outlet conduit 132 to the inflatable occupant restraint 134. The flow control orifice 131 partially controls the flow rate of gas toward the inflatable occupant restraint 134 and the pressure in the combustion chamber 104. The inflatable vehicle occupant restraint 134 may be as already described in the first embodiment.
[0043]
A suitable opening device 140 is coupled to the rupture disc 112. When the opening device 140 is activated, the rupture disc 112 is opened. Similarly, a suitable opening device 142 is coupled to the rupture disc 116. When the opening device 142 is activated, the rupture disc 116 is opened.
[0044]
The opening devices 140 and 142 are operated by a vehicle deceleration sensor that senses a sudden deceleration of the vehicle as a sign of a collision. As a result, hydrogen and oxygen flow into the combustion chamber 104 where they are mixed together. The vehicle deceleration sensor similarly activates the ignition device 130 and subsequently ignites the mixture of hydrogen and oxygen in the combustion chamber 104. As the mixture of gases in the combustion chamber 104 ignites, the gas warms and the pressure in the combustion chamber 104 increases. Thereafter, the gas flows into the vehicle occupant restraint tool 134.
[0045]
The amount of hydrogen and oxygen stored in the containers 100 and 101 can be changed. The amount of hydrogen in the combustion chamber 104 is preferably about 10 mol% of the total amount of hydrogen and oxygen in the combustion chamber 104. On the other hand, the amount of oxygen in the combustion chamber 104 is preferably about 90% of the total amount of hydrogen and oxygen in the combustion chamber 104. In this case, an amount of oxygen exceeding that required to promote hydrogen combustion is supplied. Thus, the vehicle restraint expands with products and oxygen from the combustion of the gas mixture in the combustion chamber 104. The combustion product contains water vapor.
[0046]
(Example 5)
A fifth embodiment of the present invention is illustrated in FIGS. The components of this embodiment of the invention are generally similar to the components of the embodiments of the invention illustrated in Examples 1-4, and like reference numerals are used to indicate similar components. doing. The subscript c is added to the numbers in FIGS. 7 to 9 to avoid mixing.
[0047]
The vehicle safety device 10c (FIG. 7) includes a vehicle occupant restraint that is inflated by a gas flow from the container 14c (not shown). The container 14c is provided with a chamber 16c for holding a gas mixture 18c. The gas mixture 18c preferably includes a fuel gas, an oxidizing gas that promotes combustion of the fuel gas, and an inert gas. Alternatively, the gas mixture 18c in the container 14c may contain an oxidizing gas and a combustion gas in an amount that results in a mixture with very low combustible components. That is, the amount of oxidizing gas may exceed the amount required to promote combustion of fuel gas.
[0048]
When the gas mixture 18c ignites, it burns in the container 14c, but is not explosive if it does not ignite. A normal pressure is applied to the gas mixture 18c in the container 14c. The gas mixture 18c is of the same composition as the gas mixture 18 detailed in connection with the embodiment of the invention illustrated in FIGS.
[0049]
When the vehicle suddenly decelerates (not shown here), any type of deceleration sensor of known and appropriate construction transmits a signal to the conductors 150, 152 to activate the ignition device 24c. The ignition device 24c is activated to ignite the fuel gas in the gas mixture 18c. Combustion of the fuel gas in the mixture 18c is promoted by the oxidizing gas. As the fuel gas burns, the pressure in the chamber 16c increases. Such an increase in pressure is due to heat supplied by the ignition device 24c and the combustion of the fuel gas.
[0050]
When the pressure in the chamber 16c reaches a predetermined pressure or after a predetermined time has elapsed, the rupture disc (not shown here) in the rupture disc assembly 156 has ruptured and one or more flow rates. Warm gas flows into the vehicle occupant restraint through the control orifice. As the gas flows into the vehicle occupant restraint, the gas causes the vehicle occupant restraint to expand to a predetermined location for restraining the vehicle occupant.
[0051]
According to features of this embodiment of the present invention, the ignition device 24c is activated to transmit energy through the non-porous wall 160 (FIG. 8) of the container 14c, and the gas mixture 18c in the container 14c is transferred. It can be burned to ignite. The ignition device 24 c is disposed adjacent to the non-porous outer wall surface 166 of the wall portion 160. The outer loading material 164 is enclosed in a cylindrical metal housing 170. The metal housing 170 is welded to the non-porous outer portion 166 of the wall portion 160. The outer loading material 164 is engaged with the non-porous outer portion 166 of the wall 160.
[0052]
The inner ignitable loading material 174 is placed in engagement with the non-porous inner portion 176 of the wall 160. Inner charge material 174 is encased in a cylindrical metal housing 178. The metal housing 178 is welded to the non-porous inner portion 176 of the wall portion 160. The cylindrical sealing disk 186 prevents exposure of the inner charge material to the gas mixture in the chamber 18c.
[0053]
In one particular embodiment of the present invention, the outer ignitable charge 164 may be RDX (Royal Danish Explosive). However, if desired, HMX (Her Majesty's Explosive) could be used. Both cross sections of the outer charge material 164 and the inner charge material 174 are cylindrical with a diameter of about 0.100 inch.
[0054]
In the particular embodiment already illustrated of the present invention, the inner loading material 174 is contained in two compartments. A cylindrical outer partition 180 and a cylindrical inner partition 182. The outer partition 180 is made of pentaerythritol tetranitrate. The inner compartment 182 is boron potassium nitrate (BKNO₃). In this particular embodiment of the invention, cylinder 14c is formed by remelting 304 stainless steel with a vacuum arc. The thickness of the cylinder wall 160 between the outer charge material 164 and the inner charge material 174 is about 0.085 inches.
[0055]
The igniter 24c includes an extended ignition line 192. The ignition line 192 has an end 194 and is disposed adjacent to the internal charge 174 and the sealing disk 186. In FIG. 8, the end 194 of the ignition line 192 is nested in the housing 178, the end of the ignition line 192 is connected adjacent to the sealing disc 196, and is positioned adjacent to the internal charge 174. . The central axis in the longitudinal direction of the ignition line 192 is disposed so as to coincide with the central axis in the longitudinal direction of the container 14c. The ignition line 192 extends from the housing 178 through the center of the container 14c to the right end portion of the container in FIG. The ignition line 192 has an end, indicated at 196 in FIG. 7, which is positioned adjacent to the burst disk assembly 156.
[0056]
Although the end 196 of the ignition line 192 is shown as not supported in FIG. 7, the support can be provided inside the burst disk assembly or on the lateral wall of the container 14c. Further, if desired, the ignition line 192 can be offset off to one of the central axes of the container 14c.
[0057]
The ignition line 192 shown in FIG. 8 has a cylindrical sheath 202. The sheath 202 is a woven fabric of brittle material such as plastic, ceramic or composite. An elongated core 204 is disposed inside the sheath 202. The core 204 is a non-explosive and ignitable material, and is formed of a material having high combustion heat.
[0058]
The core 204 is formed of three cylindrical strands 206, 208, and 210 (FIG. 9) and is confined by the open cylindrical side wall of the sheath 202. Strands 206, 208 and 210 include a longitudinally extending support member 214, which is coated with a mixture of non-explosive, ignitable powdered fuel, oxidant and a suitable binder. The support member 214 is a fabric such as glass fiber, metal or polymer material.
[0059]
The area delimited by the sheath 202 is larger than the cross-sectional area of the core 204. As a result, spaces are created between the core strands 206, 208, 210 and the sheath 202, and between the core strands themselves. A powder adhesive ignition layer 222 made of the same material as the strands 206, 208, 210 is disposed inside the sheath 202.
[0060]
Ignition line 192 is commercially available from Explosive Technology (Fairfield California) and is known as ITLX. An ignition line 192 having a core 204 formed of three strands 206, 208, and 210 and a cylindrical sheath 202 has already been disclosed, and it is contemplated that the ignition line 192 can take a variety of different configurations. For example, it is shown in US Pat. No. 4,220,087 issued September 7, 1980 under the name “Linear Ignition Fuse”.
[0061]
When the vehicle is suddenly decelerated, a deceleration sensor (not shown) transmits a signal via lines 150, 152 to ignite the external charge 164. The ignition of the external charge 164 causes the non-opening wall portion 160 of the container 14c to vibrate. The force transmitted by the vibration of wall portion 160 between charges 164 and 174 causes ignition of ignition portion 180 of internal charge 174. This ignites the charge portion 182. The ignition of charge portions 180 and 182 of internal charge 174 destroys sealing disk 186 and ignites core 204 at the end of ignition line 192.
[0062]
Upon ignition of the core 204, the ignition reaction propagates along the ignition line at a very fast rate, on the order of 1,000-1500 meters per second. As the reaction propagates along the ignition line 192, the sheath 202 is broken. The sheath 202 is broken, resulting in small incandescent particles of reaction product released radially from the ignition line 192.
[0063]
The heat obtained by ignition of the ignition line 192 rapidly heats the gas near the surface of the sheath 202 and quickly raises the temperature to about 1,000 ° F. This ignites the combustible mixture 18c of gas in the chamber 16c. Furthermore, the small incandescent particles of reaction product released radially from the ignition line 192 resulting from the destruction of the sheath effectively ignite the combustible gas mixture 18c at a location remote from the ignition line.
[0064]
That is, the ignition line 192 plays two roles of heating the gas mixture 18c inside the container 14c and igniting the gas mixture. The ignition line 192 increases the substantial amount of heat to the gas mixture 18c and requires less fuel gas than when a different type of igniter is used.
[0065]
Based on the above description of the present invention, those skilled in the art can make applications, improvements, changes and modifications. For example, the gas inside the container 101 of FIG. 6 may contain an inert gas such as nitrogen together with oxygen. In a variation of the embodiment of FIG. 6, the inert gas can also be stored under pressure inside a separate container similar to containers 100 and 101. The device according to the present invention can be used as another inflating device in addition to restraining a vehicle occupant known as an air bag. For example, the device according to the present invention can be used for an inflatable automobile seat belt, raft, escape chute, and the like. Applications, improvements, changes, modifications, and the like that can be easily made by those skilled in the art are included in the technical scope of the present invention.
[Brief description of the drawings]
FIG. 1 is a schematic diagram of one embodiment of the present invention.
FIG. 2 is a schematic diagram of a second embodiment of the present invention.
FIG. 3 is a schematic view of a third embodiment of the present invention.
FIG. 4 is a sectional view of a part of a vehicle occupant safety device according to the present invention.
FIG. 5 is a graph showing performance characteristics of a typical vehicle occupant safety device according to the present invention.
FIG. 6 is a schematic view of a fourth embodiment of the present invention.
FIG. 7 is a schematic view of a fifth embodiment of the present invention.
8 is a fragmentary enlarged schematic view of a portion of the apparatus of FIG.
9 is a cross-sectional view taken along line 9-9 of FIG.
[Explanation of symbols]
10 Passenger safety device
12 Inflatable vehicle occupant restraint
14 containers
18 Gas mixture
22 Deceleration sensor
24 igniter

Claims (6)

A method of inflating a vehicle occupant restraint,
Storing a first gas in the first chamber;
Storing a second gas comprising a combustible gas mixture in a second chamber;
Releasing the first and second gases at different times and flowing from the first and second chambers at the different times;
Igniting the combustible gas mixture after the first gas is released from the first chamber;
Sending the first gas and the ignited combustible gas mixture into the vehicle occupant restraint;
Including methods. A method of inflating a vehicle occupant restraint,
Supplying a combustible gas mixture into the combustion chamber comprising at least one stored fuel gas and a stored oxidant gas that promotes combustion of the fuel gas;
Igniting a fuel gas in the combustion chamber to provide a heated gas and high pressure in the combustion chamber, thereby forming an inflation gas for a vehicle occupant restraint in the combustion chamber;
A method of supplying the expansion gas from the combustion chamber to the vehicle occupant restraint without mixing the expansion gas with other stored gas. A method for inflating the vehicle occupant restraint according to claim 2,
The method wherein providing the combustible gas mixture comprises providing an inert gas in the combustion chamber. A method for inflating a vehicle occupant restraint device according to claim 2 or claim 3,
The step of supplying a gas mixture of combustible gas storing the fuel gas in a container;
Storing the oxidant gas in a separate container;
Responsive to rapid vehicle deceleration, mixing the fuel gas and oxidant gas in the combustion chamber to generate a combustible gas mixture. A method for inflating the vehicle occupant restraint according to claim 2,
The method wherein the step of igniting the fuel gas in the vessel includes transferring energy through a non-porous portion of the vessel wall. A method for inflating the vehicle occupant restraint according to claim 2,
The step of igniting the fuel gas in the container includes releasing incandescent material into a gas mixture in the container along an elongated path extending from one end portion of the container through a central portion of the container. Method.

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