JP3914812B2 - Gas generator for air belt device and air belt device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a device for protecting a passenger of a moving body such as a vehicle, an aircraft, a high-speed ship, etc., in the event of a vehicle collision, and in particular, is mounted on the passenger like a seat belt and gas from a gas generator The present invention relates to an inflatable belt device.
[0002]
[Prior art and problems to be solved by the invention]
The air belt device inflates at least a part of the belt portion of the seat belt device (particularly, the portion that hits the occupant's body) when the vehicle collides or rolls over. Usually, this device is provided with an air belt that introduces gas into the belt and inflates, and includes a gas generator that supplies gas into the air belt, and the gas generator operates in the event of a vehicle collision or the like. It is provided as a thing.
[0003]
For example, Japanese Patent Application Laid-Open No. 5-85301 (US Pat. No. 5,346,250) relates to mounting of an air belt on a vehicle. In this document, one end of an air belt is connected to a tongue, a gas passage is provided in each of the tongue and a buckle to which the tongue is attached, and gas is introduced into the air belt through the gas passage. . The two gas passages are connected by inserting a tongue into the buckle.
[0004]
Since such an air belt device is usually used for a long period of time after being attached to a vehicle, it must be surely operated even when used for many years.
[0005]
However, the current situation is that the adverse effects caused by long-term use and solutions to these problems have not yet been provided.
[0006]
Therefore, the present invention recognizes the adverse effects caused by long-term use and further provides means for solving the adverse effects. More specifically, in the conventional air belt apparatus, it is conceivable that foreign substances are clogged in the gas flow path (that is, in the conduit) due to long-term use, and the gas discharge port of the gas generator is blocked. In this case, since the gas generated in the gas generator is not normally discharged, the gas generator may be ruptured. In particular, the gas discharge port in the gas generator is closed with a closing member (such as a seal tape or a rupture disk), and the increased pressure inside the housing (the increase in the pressure inside the housing generates gas or generates heat). In the case of a gas generator that releases gas by rupturing, the internal pressure of the housing rises temporarily, but when the closing member should be broken, the gas generator gas discharge If the outlet is clogged with foreign matter, the gas generator housing itself may be destroyed. Accordingly, the present invention focuses on this as a problem, and provides a gas generator and an air belt device for an air belt device that can ensure operational safety without causing any harmful effects that the gas generator bursts even when used for many years. It is to provide.
[0007]
Japanese Patent Application Laid-Open No. 2001-322522 discloses a technique for reducing the pressure load applied to a member such as an air belt, but this is applied to the air belt when the gas pressure from the gas generator is excessively high. It prevents the applied stress from increasing, and does not solve the problems derived from long-term use. In fact, what is described in this document is to avoid rupture of the gas generator because the gas can no longer be escaped if foreign matter is clogged in the inlet pipe (especially near the gas outlet). I can't.
[0008]
[Means for Solving the Problems]
The present invention recognizes the risk of rupture of the gas generator due to clogging of the gas discharge port of the gas generator due to clogging of the gas flow path (that is, inside the conduit) after many years of use, and investigates the cause. The present invention has been made.
[0009]
That is, the blockage of the gas flow path (i.e., in the conduit) due to long-term use is caused by the fact that a conventional gas generator discharges gas in the axial direction of the housing, and this discharged gas is provided along the discharge direction. Because it passes through the cylindrical discharge pipe (or introduction pipe), foreign substances are likely to be clogged in the gas outlet and discharge pipe (or introduction pipe). We will investigate and further solve this problem. Therefore, the gas generator and the air belt device of the present invention are improved in the jet direction of the gas discharged from the gas generator (the gas for expanding the air belt) and the structure in the vicinity of the gas discharge port.
[0010]
That is, the gas generator for an air belt device according to the present invention is a gas generator used in an air belt device that introduces a gas discharged from the gas generator and expands the air belt. And a solid gas generating agent that generates at least one of heat and a housing that contains the solid gas generating agent, and the housing includes a gas discharge port that discharges the gas generated inside. The gas discharge port discharges gas in the radial direction of the housing.
[0011]
Since the gas discharge port discharges gas in the radial direction of the housing, it is possible to avoid the risk that the gas discharge port is clogged with foreign substances as much as possible. Also, even if foreign matter enters the axial direction of the gas generator and closes the conduit (discharge pipe or introduction pipe) through which the gas flows, the gas is discharged in the radial direction from the gas discharge port. Other means (escape path) other than the normal flow path (that is, the flow path passing through the conduit) can be easily secured by means as described later. If such another flow path (escape path) is secured, an abnormal pressure increase in the gas generator can be avoided.
[0012]
In addition, by making the gas discharge direction the radiation direction of the gas generator, it is possible to improve the safety of the gas generator in distribution and assembly. In other words, in the present invention, the gas generators can be operated in an error by providing the gas outlets that discharge the gas in the radial direction evenly in the circumferential direction and at the positions that offset at least the propulsive force of the discharged gas. It is possible to eliminate the situation where the gas generator itself is propelled and moved by the exhausted gas. In order to make this effect more remarkable, the assembly of the conduit is preferably performed at the final stage in the assembly of the air belt device.
[0013]
In order to secure the escape route for the gas discharged in the radial direction, a conduit directly connected to the gas generator housing is arranged so that the end thereof covers and covers the gas discharge port, and at least the gas discharge port is provided in this conduit. This can be done by forming a gas pressure release means for releasing the gas in the pipe when the pressure in the conduit in the vicinity exceeds a certain level.
[0014]
The conduit directly connected to the gas generator housing is a conduit that first receives the gas discharged from the gas generator, and not only a conduit that contacts the gas generator housing but also a seal member such as an O-ring or a conduit other than the conduit. In addition, a conduit connected via a connecting structure (for example, a flange member) is also included. As such a conduit, when the gas discharged from the gas generator is led directly to the air belt through the introduction pipe, this introduction pipe corresponds, and the gas discharged from the gas generator is supplied to the gas generator. This exhaust pipe corresponds to the case where it is led to the introduction pipe via the connected exhaust pipe. Of course, such a pressure release means may be provided in the discharge pipe.
[0015]
The gas pressure release means has a structure that deforms or opens due to the pressure in the pipe that has risen by the gas discharged from the gas generator when a foreign substance is clogged in the conduit (that is, the same as the “introduction pipe or discharge pipe”). a member, activated when it becomes when the internal pressure of the conduit in the vicinity of the gas outlet exceeds a specific, i.e., constant pressure inside the pressure rises in the clogging within the conduit foreign matter into the tube (P _X) or To do.
[0016]
Normally, at the initial stage when the gas from the gas generator flows into the conduit, the pressure in the conduit is temporarily increased (the pressure at this time is P _Y ), but the pressure in the conduit (P _Y ) will fall as the gas flows toward the air belt. Therefore, means outlet gas圧放in the present invention, depending on the output performance of the gas generator is formed as being activated when the relational expression of at least P Y _{<P X} holds. That is, the gas pressure release means in the present invention is formed so as to operate at a pressure (that is, P _X ) equal to or higher than the pressure (P _Y ) in the conduit that temporarily rises. This is because the function of the air belt device cannot be secured if the gas pressure releasing means operates below this pressure (P _Y ).
[0017]
Such gas pressure releasing means can be formed as follows, for example.
[0018]
That is, the conduit directly connected to the gas generator housing is formed in a substantially cylindrical shape, and the end portion on the side covering the gas discharge port is formed as an inward flange-shaped flange portion, and the front end of the flange portion is the gas generator housing Arrange the conduit so that it touches. Then, if the portion near the flange portion of the conduit is formed to be deformed by a conduit internal pressure (P _X ) above a certain level, and a gas discharge gap is formed between the housing and the conduit, gas is released from the gas discharge gap. be able to. In this case, the flange portion itself may be deformed. In the case of forming in this way, in order to surely perform deformation due to the internal pressure of the conduit exceeding a certain level, it acts at a pressure (P _X ) higher than the pressure (P _Y ) in the conduit that temporarily rises as described above. In addition, the thickness, material, dimensions and shape of each part of this conduit are adjusted, and the pressure inside the conduit (P) exceeds a certain level without being deformed by the gas discharge pressure (P _Z ) from the gas discharge port. _X ) can only be deformed.
[0019]
In addition, the conduit directly connected to the gas generator housing is formed in a cylindrical shape, and a fragile portion is formed on the peripheral surface thereof, and the fragile portion is formed so as to be broken by a predetermined pressure inside the conduit (P _X ). You can also As such a weak part, for example, a notch or a cut is provided on the peripheral surface of the conduit existing in the vicinity of the gas discharge port, and an opening is formed in the vicinity of the gas discharge port of the conduit. It can be performed by coating with, for example. When formed in this way, the depth of the notch, the size of the cut, the opening diameter, and the thin film strength need to be adjusted so as to open at a certain conduit internal pressure (P _X ).
[0020]
In addition, when the pressure in the conduit reaches a predetermined value (P _X ) or more, the internal pressure (P _X ) that has risen above a certain level is released by tearing the portion near the gas outlet in the conduit. A gas pressure release means can be formed.
[0021]
Thus, the gas pressure releasing means formed in the gas generator includes a pressure (P _Y ) in the conduit that temporarily rises when the gas generator is operated, and a gas discharge pressure (P _Z ) from the gas discharge port. Operating at a higher pressure in the conduit (P _X ).
[0022]
In the gas generator of the present invention described above, normal operation, that is, operation in a state where the inside of the conduit is not clogged, when gas is discharged radially from the gas discharge port, the flow direction is changed by hitting the inner peripheral surface of the conduit. And will pass through the conduit as usual. Therefore, it is necessary to ensure a gap for gas circulation between the gas discharge port and the inner peripheral surface of the conduit. Therefore, in the gas generator according to the present invention, in order to ensure a gap for gas flow between the gas discharge port and the inner peripheral surface of the conduit, the portion where the gas discharge port is formed is the gas generator housing body. It is desirable that the outer diameter is made smaller than (the part containing the gas generating agent). In this sense, it is preferable that the housing has a cylindrical shape and a gas exhaust port is provided at one end thereof.
[0023]
In the gas generator according to the present invention, it is necessary to accommodate at least a gas generating agent that generates gas or heat by combustion in the housing. By accommodating such a gas generating agent, the internal pressure of the housing rises above a certain level during operation. Further, in addition to the gas generating agent, the housing can be filled with a pressurized gas for inflating the air belt. Of course, it may contain only pressurized gas.
[0024]
In addition, this gas generator is provided with an operating device (for example, an igniter) for burning the gas generating agent, or a structure in which outside air does not enter the housing before the operation of the gas generator. A conventionally well-known structure is employable about accompanying (for example, the member which obstruct | occludes a gas exhaust port).
[0025]
The gas generator can be used together with an air belt that expands when gas is introduced to form the air belt device of the present invention. In manufacturing the air belt device, the conduit directly connected to the gas generator housing can be used as a component of the air belt device or a component of the gas generator. The conduit may constitute a part of the air belt.
[0026]
A conventionally well-known technique can be used regarding necessary members and structures other than the gas generator and the conduit directly connected to the gas generator, such as an air belt used in manufacturing the air belt device.
[0027]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, the present invention will be described based on embodiments shown in the drawings.
[0028]
FIG. 1 is a perspective view showing a main part of the air belt device according to the first embodiment, FIG. 2 is a cross-sectional view showing a main part of the operation of the air belt device of FIG. 1, and FIG. FIG. 4 is a main part perspective view showing still another example of the gas pressure releasing means, and FIG. 5 is a main part perspective view showing an air belt device according to another embodiment.
[0029]
In the inflatable belt apparatus shown in FIG. 1, an inflatable air belt 10 is provided in a belt portion that restrains an occupant, and a tongue Y is connected to the inflatable belt portion (or inflatable belt 10). The tongue Y is provided with an introduction pipe 3 as a conduit for introducing the gas from the gas generator 1 and guiding it to the air belt 10.
[0030]
On the other hand, the buckle X extending from the floor or seat of the vehicle is provided with a gas generator 1 that receives an operation signal and generates gas that inflates the air belt 10. The gas generator 1 includes a gas discharge port 2 for discharging a gas generated by combustion of a gas generating agent (not shown) (or by expansion due to combustion heat). The gas generator 1 is equally provided on the peripheral surface on the end side in the housing.
[0031]
Then, an inward flange-shaped flange portion 4 is formed at the gas generator side end portion of the introduction pipe 3, and when the tongue Y and the buckle X are coupled, the inner peripheral surface of the flange portion 4 is The gas generator 1 is formed so as to be in contact with the outer peripheral surface of the housing (outer container). At this time, the gas outlet 2 is naturally present in the introduction pipe 3.
[0032]
In the air belt apparatus configured as described above, as shown in FIG. 2 (a), even if foreign matter Z is mixed into the introduction pipe 3 due to long-term use and the gas flow path is closed, the gas is gas Since it is discharged from the generator 1 in the radial direction, as shown in FIG. 2 (b), it is possible to secure a escape path in another direction (in the drawing, diagonally backward direction). As a result, since an abnormal pressure increase in the gas generator housing can be prevented, a situation in which the housing bursts can be avoided.
[0033]
As the structure of the air belt itself 10 in the air belt apparatus shown in FIG. 1, a conventionally known technique such as the technique described in Japanese Patent Application Laid-Open No. 2001-322522 can be used, and the internal structure of the gas generator 1 such as a gas can be used. Since a conventionally known technique can be used for the structure of an ignition means (for example, an igniter) that operates upon receiving a generating agent or an operation signal and burns the gas generating agent, a detailed description will be given in this embodiment. Is omitted. Furthermore, since a conventionally well-known technique can be used also about the apparatus for sending an operation signal to the ignition means (igniter etc.) contained in the gas generator 1, detailed description is abbreviate | omitted in a present Example.
[0034]
In FIG. 2 (b), a portion near the flange portion 4 is deformed by receiving a pressure of a certain level or more to form a gap for discharging gas, and the introduction pipe deforms due to the pressure in this way. A portion in the vicinity of the flange portion 3 is a gas pressure releasing means. In the present embodiment, in order to ensure deformation of the vicinity of the flange portion 4 due to such gas pressure, the introduction tube 3 (that is, the conduit) is formed in a cylindrical body using stainless steel. As a result, there is no deformation depending on the gas pressure discharged from the gas discharge port 2, and only the pressure in the introduction pipe 3 when the introduction pipe 3 is clogged.
[0035]
Further, when forming the gas discharge means, without forming the flange portion 4 as shown in FIG. 1, the gas generator side of the introduction pipe 3 is formed into a cylindrical shape as shown in FIG. A sealing material 7 such as a ring can also be provided. In this case, the sealing material 7 is in close contact with the housing of the gas generator 1 and seals between the introduction pipe 3 and the gas generator 1. Even if formed in this way, it is necessary to ensure a certain gap between the gas discharge port 2 and the introduction pipe 3 in order to realize gas flow. In the gas generator 1 shown in FIG. 3 (a), when the foreign matter Z is clogged in the introduction pipe 3, and the internal pressure of the introduction pipe 3 rises above a certain level, as shown in FIG. 3 (b), the introduction pipe The vicinity of the opposing surface of the gas discharge port 2 in FIG. 3 is bent, and a flow path for allowing gas to escape can be formed.
[0036]
Further, the gas pressure release means can be formed as a weak portion at a position facing the gas discharge port 2 in the introduction pipe 3. For example, as shown in FIG. 4, in a state where the gas generator 1 and the introduction pipe 3 are connected, only the pressure in the introduction pipe 3 when the introduction pipe 3 is clogged in the vicinity of the opposing surface of the gas discharge port 2. A cut 5 that deforms and opens can be formed as the fragile portion. In this case, the cut portion 5 is opened by the abnormal pressure rise in the introduction pipe 3, and the pressure in the introduction pipe 3 is released.
[0037]
Further, the gas pressure release means is formed by forming a hole in the vicinity of the surface of the introduction pipe facing the gas discharge port, and closing the hole with a metal foil such as a sealing tape that is broken by the pressure inside the introduction pipe of a certain pressure or higher. can do. The pressure at which the metal foil is torn can be adjusted by the diameter and area of the holes, the number of holes, the material and thickness of the metal foil, and the like.
[0038]
In the case where the gas pressure releasing means is formed by using a fragile portion or a metal foil, it is desirable that the gas pressure releasing means is formed avoiding a place where the gas from the gas outlet directly hits.
[0039]
In the air belt device shown in FIGS. 1 to 4, in a state where the introduction pipe 3 is not clogged (that is, in a normal state), the gas discharged in the radial direction from the gas discharge port 2 is the inner circumference of the gas discharge port 2 and the introduction pipe 3. It passes through the gap between the surfaces and passes through the introduction pipe 3 in the length direction.
[0040]
In the inflatable belt device shown in FIGS. 1 to 4, the introduction pipe 3 constituting a part of the inflatable belt 10 is directly connected to the gas generator 1, but as shown in FIG. It is also possible to adopt a mode in which a conduit for connecting the gas generator 1 and the introduction tube 3, that is, a discharge tube 6 is provided directly connected to the housing. In this case, the aspect of the gas pressure releasing means, that is, the vicinity of the flange portion 4 that deforms at a certain gas pressure or higher is provided in the exhaust pipe 6 (that is, the conduit directly connected to the housing of the gas generator 1). It will be.
[0041]
That is, the air belt device of the embodiment shown in FIG. 5 is a gas generator for the buckle X extending from the floor or seat of the vehicle and the point where the introduction pipe 3 is provided in the tongue Y provided in the belt portion (or the air belt 10) of the seat belt. 1 is the same as that shown in FIG. However, the embodiment shown in FIG. 5 is similar to FIG. 1 in that the gas generator 1 and the introduction pipe 3 are connected via the discharge pipe 6 and the introduction pipe 3 is not directly connected to the gas generator 1. It is different from the air belt device shown.
[0042]
In the air belt apparatus shown in this embodiment, one end of the discharge pipe 6 is directly connected to the gas generator 1, and therefore, the gas pressure releasing means is provided in a portion of the discharge pipe 6 connected to the gas generator 1. Yes. Of course, the gas pressure releasing means may be formed also in the introduction pipe 3 coupled to the opposite end of the discharge pipe 6.
[0043]
In the air belt device configured as described above, even if the foreign matter Z enters the introduction pipe 3 or the discharge pipe 6 and the pressure in the vicinity of the gas discharge port 2 rises abnormally, the air belt device is provided in the discharge pipe 6. The gas pressure releasing means thus acted allows the gas to escape. Therefore, even in the gas generator 1 shown in this embodiment, an abnormal pressure increase in the housing can be prevented, and a situation in which the gas generator 1 housing bursts can be avoided.
[0044]
【The invention's effect】
The air belt device-like gas generator of the present invention configured as described above discharges gas in the radial direction of the housing, so that even if foreign matter is clogged in the conduit and there is no normal flow path, The flow path can be secured.
[0045]
In particular, in the case where the gas generator is provided with a conduit, when the internal pressure of the conduit rises above, a gas escape passage can be formed by deforming or cutting a part of the conduit.
[0046]
As a result, even if the gas flow path (ie, inside the conduit) is clogged with long-term use and the gas outlet of the gas generator is blocked, the abnormal pressure rise in the gas generator will occur. There are provided a gas generator for an air belt device and an air belt device which can prevent the trouble such as the gas generator housing from rupturing and can ensure the operation safety for a long time.
[0047]
In addition, since the gas generator of the present invention uses the gas discharge direction as the gas generator radiation direction, the gas discharged even if it malfunctions during the distribution and assembly of the gas generator. Since the propulsive forces are offset from each other, it is possible to eliminate the gas generator itself and to ensure safety during distribution and assembly.
[Brief description of the drawings]
FIG. 1 is a main part perspective view showing an air belt device according to a first embodiment. FIG. 2 is a main part sectional view showing an operation of the air belt device of FIG. 1. FIG. FIG. 4 is a perspective view of a principal part showing still another example of gas pressure releasing means. FIG. 5 is a perspective view of a principal part showing an air belt device according to another embodiment.
1 Gas generator
2 Gas outlet
3 Introduction pipe
4 Flange
5 breaks
6 Discharge pipe
7 Sealing material
10 Air belt
X buckle
Y tongue
Z foreign matter

Claims (9)

A gas generator used in an air belt device that introduces gas discharged from a gas generator and expands an air belt, the gas generator burning and generating at least one of gas and heat A generating agent and a housing containing the solid gas generating agent;
The housing includes a gas discharge port for discharging a gas generated inside, and the gas discharge port discharges gas toward a radial direction of the housing ,
The gas generator further includes a conduit that guides the gas discharged from the gas discharge port to the air belt, and one end portion of the conduit covers the gas discharge port and is disposed opposite to the gas generator.
The conduit is formed with a gas pressure releasing means for discharging the gas in the conduit by deforming the surface facing the gas exhaust port when the internal pressure of the conduit in the vicinity of the gas exhaust port exceeds a certain level. A gas generator for an air belt device. The conduit has a substantially cylindrical shape in which an inward flange portion is formed at an end portion on one end side that covers the gas discharge port, and the distal end of the flange portion is disposed in contact with the housing.
The gas圧放detecting means is deformed by a certain or more conduits inside pressure to form a gap for discharging gas, the gas generator of claim 1, wherein a flange portion near the portion of the conduit. The gas generator according to claim 2 , wherein the gas pressure releasing means is the flange portion that is deformed outward. 3. The gas according to claim 1, wherein the conduit has a cylindrical shape, and a weak portion is formed on a peripheral surface thereof, and the gas pressure releasing means is a weak portion that is damaged by a pressure inside the conduit of a certain level or more. Generator. The gas generator according to any one of claims 1 to 4 , wherein the housing is further filled with a pressurized gas for inflating the air belt. And air belt that expands by the gas is introduced, a belt apparatus which is configured to include a gas generator for supplying gas to the air belt,
The gas generator according to claim 1, wherein the gas generator is an air belt device. Before Kishirube pipe, it is formed in a substantially cylindrical shape and inward flange-like flange portion side end portion to cover the gas outlet connected directly to the gas generator, against the tip of the flange portion to said housing arrangement being, said gas圧放detecting means is deformed by a certain or more conduits inside pressure to form a gap for discharging gas, according to claim 6, wherein one formed in the flange portion adjacent portion of the conduit Air belt device. The air belt device according to claim 7 , wherein the gas pressure release means is the flange portion that is deformed outward. Before Kishirube tube is a cylindrical shape, that is in the vicinity of the gas outlet facing surface of the peripheral surface is formed with fragile portions, the gas圧放releasing means is a fragile portion to be damaged by certain more conduits internal pressure The air belt device according to claim 6 or 7 .

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