JP4579468B2 - Inflator with cap - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an inflator with a cap suitable as an inflator for a curtain of an automobile or the like, an inflator for a side airbag, an airbag device using the inflator with a cap, and a method for assembling an airbag device using the inflator with a cap.
[0002]
[Prior art and problems to be solved by the invention]
The inflator for an inflatable safety system of an automatic vehicle has an airbag inflator for a driver's seat and an airbag for a passenger's seat so that optimal occupant protection can be provided according to the seat position in the vehicle such as the driver's seat and passenger seat. Various inflators such as an inflator for a vehicle, an inflator for a side airbag, an inflator for a curtain, an inflator for a knee bolster, an inflator for an inflatable seat belt, an inflator for a tubular system, and an inflator for a pretensioner are known. Among these inflators, the curtain inflator instantly inflates and deploys a curtain-like airbag having a thickness of several centimeters on the window side of the vehicle when the vehicle receives an impact from the lateral direction.
[0003]
The following are known as related prior art. For example, US Pat. No. 5,527,066 discloses an apparatus for expanding a flexible container using helium and hydrogen together, and US Pat. No. 5,782,486 discloses a pressurized inert gas. A gas flow device for an airbag using gas is disclosed, and the specification of 3,680,886 discloses an airbag device for inflating an airbag with nitrogen or helium. No. 803,493 discloses a side inflator housing for an air bag in which a pressurized gas and a gas generating agent are used together. In registered utility model publication No. 3031246, argon or nitrogen is used as a pressurized gas. A pressurized gas inflator was disclosed.
[0004]
Various inflators are required to be smaller and lighter due to the demand for weight reduction of the vehicle itself, and are also required to improve workability, simplify the manufacturing process, and improve safety during operation. None of the prior arts can satisfactorily satisfy all of these.
[0005]
For example, when assembling an airbag device using a curtain inflator, it is necessary to connect the inflator and the airbag. However, the conventional technique has the following problems, so there is room for improvement. Next, this problem will be described with reference to FIG. FIG. 3 is a cross-sectional view for explaining a method of connecting the inflator 10 and the airbag 50.
[0006]
The inflator 10 includes an inflator housing 12 and a diffuser portion 20 connected to each other, and the internal space 16 is filled with a pressurized medium made of an inert gas at a high pressure. The diffuser unit 20 includes an igniter 26 for destroying the rupturable plate 19, a connector 30 connected to the igniter 26, and a lead wire 32 connected to the connector 30 and connected to an external power source.
[0007]
The inflator 10 and the airbag 50 are connected by a method in which the diffuser portion 20 is wrapped in the opening 52 of the airbag 50, the gas exhaust port 22 is wrapped, and then tightened with a band-shaped fastening tool. Is done. At this time, as shown in FIG. 3, the lead wire 32 is not fixed and is in a hung state, so that the lead wire 32 is pulled into the airbag 50 as it is, and the installation work of the airbag 50 is hindered. It will come. Therefore, an operator usually works with the lead wire 32 held by hand, but at that time, care must be taken so that the lead wire 32 does not overlap the gas discharge port 22. For this reason, the work becomes complicated and the burden on the worker increases. Moreover, since the lead wire 32 exists in the connection part of the inflator 10 and the airbag 50, a connection part does not become a plane, and there exists a possibility that airtightness may be impaired with progress of years.
[0008]
It is an object of the present invention to provide an inflator with a cap that can achieve a reduction in size and weight, improve workability, and simplify a manufacturing process, an airbag device using the inflator, and an assembly method of the airbag device.
[0009]
[Means for Solving the Problems]
As a means for solving the above-mentioned problems, the present invention provides a cylindrical inflator housing in which one end side is closed and the other end side has an opening, the inside of which is filled with a pressurized medium, and the opening side of the inflator housing And a diffuser portion having a first gas discharge port for discharging a pressurized medium flowing out from the opening portion during operation to the outside, and pressurization between the opening portion of the inflator housing and the diffuser portion The medium outflow path is blocked by a rupturable plate, and the diffuser portion is provided with a means for breaking the rupturable plate. A part or substantially all of the outer surface of the diffuser portion is covered with a cap. An inflator with a cap (hereinafter referred to as an “inflator”) is provided.
[0010]
In the present invention, “substantially all” means the entire remaining after securing the ejection path of the pressurized medium ejected from the first gas discharge port in order to maintain the function as an inflator. .
[0011]
Thus, by covering the outer surface of the diffuser part with the cap, each component constituting the diffuser part can be held so as not to fall off. In addition, as a requirement for performing the above-described operation, it is desirable that the internal shape of the cap is identical or approximate to the external shape of the diffuser portion.
[0012]
In the inflator of the above invention, the cap is made of an elastic member, and a part or substantially all of the outer surface of the diffuser portion can be covered with being pressed from the outside by the cap.
[0013]
By using the cap as an elastic member in this way, it is easy to attach the cap to the diffuser part, and it is easy to hold the components constituting the diffuser part so that they do not fall off due to the pressing force from the outside due to elasticity. Become.
[0014]
In the inflator of the present invention, the cap has an opening serving as the second gas discharge port, and the second gas discharge port communicates with the first gas discharge port of the diffuser portion, and the jet is ejected from the first gas discharge port. The gas can be ejected from the second gas outlet. In such a case, it is desirable that the central axis of the first gas exhaust port coincides with the central axis of the second gas exhaust port.
[0015]
By providing the cap with an opening serving as a second gas discharge port communicating with the first gas discharge port, the pressurized medium is smoothly ejected from the first gas discharge port of the diffuser portion.
[0016]
In the inflator of the above invention, when the gas ejected from one first gas exhaust port is ejected from one second gas exhaust port, the diameter of the first gas exhaust port is larger than the diameter of the second gas exhaust port. Can be small.
[0017]
Furthermore, in the inflator of the above invention, the total opening area of the first gas discharge port can be made smaller than the total opening area of the second gas discharge port.
[0018]
Thus, by defining the diameter and / or the total opening area of the first gas outlet and the second gas outlet, the ejection pressure of the pressurized medium can be controlled by the first gas outlet.
[0019]
Further, in the inflator of the present invention, a plurality of first gas discharge ports are provided, and at least two of the plurality of first gas discharge ports are arranged at positions that are symmetrical to each other in the width direction or at positions that approximate to them. Can be what you have.
[0020]
In the present invention, when the cross section in the width direction of the diffuser portion is circular and two or more first gas discharge ports are provided, the positions of at least two first gas discharge ports are the width direction (radial direction). ) Or close to symmetry. When an unexpected situation occurs in which an inflator malfunctions when a fire or the like occurs during transportation or storage of the inflator, if there is only one first gas discharge port, the inflator It is very dangerous to jump out like a rocket. However, as described above, when the arrangement of at least two first gas discharge ports is adjusted, the occurrence of the abnormal situation as described above is prevented.
[0021]
In the inflator according to the invention, the outer surface of the diffuser portion has a concavo-convex portion, and the concavo-convex portion corresponding to the concavo-convex portion is provided on a portion of the inner peripheral surface of the cap facing the concavo-convex portion. can do.
[0022]
In this way, the cap becomes difficult to fall off by associating the uneven portion on the outer surface of the diffuser portion with the uneven portion on the inner surface of the cap.
[0023]
In the inflator of the present invention, the breaking means provided in the diffuser portion may be attached in parallel or coaxially with the central axis of the inflator housing.
[0024]
Further, in the inflator of the present invention, the breaking means provided in the diffuser section has an igniter and a connector connected to the igniter, and the connector is pressed and fixed by the inner surface of the cap. Can do.
[0025]
By using the cap in this way, in the inflator of the invention described above, the connection between the igniter and the connector is not poor due to vibration applied from the outside, the connector is not dropped, etc., and it is prevented from becoming inoperable. The breaking means provided in the diffuser part has an igniter, a connector connected to the igniter, and a lead wire connected to the connector, and is pressed and supported by the inner surface of the cap and the outer surface of the diffuser part. Thus, the extending direction of the lead wire can be regulated.
[0026]
As shown in FIG. 3, when the lead wire connected to the connector is not fixed and is in a hanging state, it becomes an obstacle when the inflator and the airbag are connected. Furthermore, care must be taken not to overlap the lead wire with the gas outlet of the diffuser, which increases the burden on the operator.
[0027]
For this reason, as described above, by holding the lead wire so as to be sandwiched between the cap and the diffuser portion, the extending direction of the lead wire can be regulated to a desired direction. In consideration of the actual work, the lead wire extension direction is the inflator housing side direction, and the extended lead wire overlaps with the first gas discharge port of the diffuser section and the second gas discharge port of the cap. It can be regulated not to become. Therefore, it is not necessary to pay special attention to the lead wire when connecting the inflator and the airbag, so that workability is greatly improved. Further, since the cap and the airbag can be connected in a plane, the airtightness does not deteriorate with the passage of time.
[0028]
In the inflator of the present invention, the cap is preferably made of a material having elasticity such as rubber or resin, but may be made of metal such as aluminum.
[0029]
According to another aspect of the present invention, there is provided an air bag apparatus comprising: an operation signal output means comprising an impact sensor and a control unit; and a module case in which the inflator and the air bag are housed in the case. provide.
[0030]
According to another aspect of the present invention, there is provided an airbag apparatus including an operation signal output unit including an impact sensor and a control unit, and a module case in which the inflator and the airbag are accommodated in the case. When the inflator and the airbag are connected, the opening of the airbag is covered around a cap that covers part or substantially all of the outer surface of the diffuser portion of the inflator, and the string-like tightening is performed. Provided is an assembling method of an airbag device in which an airbag is fixed by fastening with an attaching means.
[0031]
In the assembling method of the present invention, a groove is formed around the outer surface of the cap that covers the diffuser portion, the opening of the airbag is covered so as to cover at least the groove, and a string-like fastening means is provided in the groove. It is desirable to tighten it so that it abuts.
[0032]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a cross-sectional view in the length direction of the inflator 10 of the present invention, and FIG. 2 is a cross-sectional view for explaining a method of connecting the inflator 10 and the airbag 50 of FIG.
[0033]
The inflator housing 12 has an opening 14 on one end side and is closed on the other end side. In the internal space 16, a pressurized medium made of an inert gas such as argon or helium or nitrogen gas has a maximum pressure of 70. It is filled at about 1,000 kPa. The inflator housing 12 has a circular cross section in the width direction, and the opening 14 is also circular.
[0034]
The inflator housing 12 can be manufactured by swaging or spinning a pipe, and a ready-made gas cylinder can be used as it is. When the pipe is swaged or spun, the one end is almost closed with the pores to be filled with the pressurized medium remaining. After the diffuser portion 20 is connected to the inflator housing 12, the pressurized medium is filled from the gap between the seal pins 17 fitted into the pores, and then the inflator housing 12 is welded at the seal pins 17 to completely close the pressure medium.
[0035]
A diffuser portion 20 is connected to the opening 14 side of the inflator housing 12, and the diffuser portion 20 has a first gas discharge port 22 for allowing the pressurized medium to flow outside.
[0036]
As shown in FIG. 1, the inflator housing 12 and the diffuser portion 20 may be connected by welding (welded portion 25), or a male screw portion is provided on the outer peripheral surface of the end portion of the inflator housing 12, and the inner periphery of the end portion of the diffuser portion 20. A female screw portion may be provided on the surface, and the male screw portion and the female screw portion may be screwed together to be connected.
[0037]
The pressurized medium outlet path 18 between the opening 14 of the inflator housing 12 and the diffuser part 20 is closed by a bowl-shaped rupturable plate 19, and the internal space 16 of the inflator housing 12 is It is maintained in a high-pressure airtight state. In FIG. 1, the rupturable plate 19 is attached to the diffuser portion 20 side, but may be attached to the opening portion 14 side of the inflator housing 12. The gas discharge port 22 of the diffuser unit 20 is not closed.
[0038]
The diffuser unit 20 is provided with an igniter 26 including an igniting agent as a means for destroying the rupturable plate 19. The igniter 26 is attached after the inflator housing 12 and the diffuser portion 20 are connected. The igniter 26 is fitted in a direction from one end opening of the diffuser portion 20 toward the rupturable plate 19, and after insertion, one end of the diffuser portion 20 is fitted. It is fixed by caulking the peripheral edge 28 of the opening. The igniter 26 is attached coaxially with the central axis of the inflator housing 12. Reference numeral 30 denotes a connector connected to the igniter 26, and 32 denotes a lead wire connected to the connector 30.
[0039]
All of the diffuser portion 20 except the first gas discharge port 22 is covered with a cap 40 made of synthetic rubber. The cap 40 is attached by covering the diffuser portion 20 with the cap 40 or by fitting the diffuser portion 20 into the cap 40, and the diffuser portion 20 is pressed from the outside by the cap 40.
[0040]
The cap 40 has an opening that becomes the second gas discharge port 42, and the central axis of the first gas discharge port 22 and the central axis of the second gas discharge port 42 coincide with each other. The pressurized medium is ejected through the first gas outlet 22 and the second gas outlet 42. Although the illustrated number of first gas discharge ports 22 is one, when a plurality of first gas discharge ports 22 are provided, the same number of second gas discharge ports 42 are provided as in FIG.
[0041]
The diameter of the first gas discharge port 22 is smaller than the diameter of the second gas discharge port 42, and the same applies when a plurality of each is provided. For this reason, the total opening area of the first gas discharge port 22 is smaller than the total opening area of the second gas discharge port 42.
[0042]
Although only one first gas discharge port 22 is provided in FIGS. 1 and 2, from the viewpoint of preventing the inflator 10 from jumping out in a rocket shape during malfunction, the first gas discharge port 22 is in a radial direction. It is also possible to provide another first gas discharge port at a position that is symmetrical with respect to. At this time, the cap 40 is provided with another second gas discharge port at a corresponding position.
[0043]
Although the internal shape of the cap 40 is a shape corresponding to the external shape of the diffuser portion 20, the welded portion 25 is a raised convex portion, and therefore the inner surface of the cap 40 corresponding to the welded portion 25 is recessed. Thus, the cap 40 can be easily attached and the cap 40 can be prevented from falling off.
[0044]
Since the connector 30 connected to the igniter 26 is pressed by the bottom surface (closed end surface) of the cap 40, the connector 30 is prevented from falling off from the igniter 26.
[0045]
The lead wire 32 connected to the connector 30 is pressed and supported by the inner surface of the cap 40 and the outer surface of the diffuser portion 20 so that the extending direction is regulated, and the first gas outlet 22 and the second gas outlet It extends to the inflator housing 12 direction side so as not to overlap with 42.
[0046]
Next, an airbag device using the inflator 10 and an assembly method thereof will be described.
[0047]
When mounted on a vehicle, the inflator 10 is installed as an airbag device combined with an operation signal output means including an impact sensor and a control unit, a module case in which the inflator 10 and the curtain-like airbag 50 are accommodated in the case, and the like. Is done.
[0048]
The inflator 10 and the airbag 50 are connected in the state shown in FIG. 2, but the lead wire 32 is fixed by the cap 40 and the extending direction is restricted. It ’s never going to happen. For this reason, the connection operation | work of the inflator 10 and the airbag 50 is easy, and compared with the case of FIG. 3, an operator's burden is reduced significantly.
[0049]
In FIG. 2, the connecting portion between the inflator 10 (cap 40) and the airbag 50 is fixed by fastening with a string-like fastening means 54 such as a rubber or metal belt, and the air before and during operation is fixed. The bag 50 is prevented from being detached from the inflator 10. A groove having the same width as the width of the string-like fastening means 54 is provided around the cap 40 with which the string-like fastening means 54 abuts, and the string-like fastening means 54 is attached so as to contact the groove. After tightening, the airbag 50 can be connected and fixed more firmly. In particular, in the case where the cap 40 is made of an elastic member, the airbag 50 can be attached with the periphery of the opening of the airbag 50 biting into the cap 40 by being firmly tightened by the string-like tightening means 54. This is desirable because there is no gap in the connection portion between the cap and the cap 40 and leakage of the pressurized medium from the connection portion can be prevented.
[0050]
Next, the operation of the airbag apparatus using the inflator 10 will be described with reference to FIG.
[0051]
When the vehicle receives an impact, the igniter 26 is activated in response to a signal from the impact sensor, and the rupturable plate 19 is destroyed by igniting and burning the igniting agent. Since the opening 14 is opened by the destruction of the rupturable plate 19, the pressurized medium in the internal space 16 flows out through the first gas discharge port 22 and the second gas discharge port 42 to inflate the airbag.
[0052]
The inflator 10 or the airbag device incorporating the inflator 10 has the diffuser portion 20 wrapped and held by the cap 40. Therefore, the connection and connector between the igniter 26 and the connector 30 due to vibration applied from the outside, etc. The connection between the lead wire 32 and the connector 30 does not become poor, and the connector 30 and the lead wire 32 do not fall off. Further, since the lead wire 32 is also fixed by the cap 40, the position of the lead wire 32 is displaced due to vibration applied from the outside, and overlaps with the first gas discharge port 22 and the second gas discharge port 42, or air The airtightness of the bag 50 is not impaired.
[0053]
【The invention's effect】
In the inflator of the present invention, since the diffuser portion is held by the cap, the connector constituting the diffuser portion is prevented from dropping off.
[0054]
Further, when assembling the airbag device using the inflator of the present invention, the assembling work is easy and the burden on the operator can be reduced.
[Brief description of the drawings]
FIG. 1 is an axial sectional view of an inflator of the present invention.
FIG. 2 is a cross-sectional view for explaining a method of connecting the inflator and the airbag of FIG.
FIG. 3 is a cross-sectional view for explaining a method of connecting an inflator and an airbag in the prior art.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 10 Inflator 12 Inflator housing 19 Rupture plate 20 Diffuser part 22 1st gas exhaust port 26 Igniter 30 Connector 32 Lead wire 40 Cap 42 2nd gas exhaust port 50 Air bag

Claims (10)

One end side is closed, the other end side has an opening, a cylindrical inflator housing filled with a pressurized medium inside, and fixed to the opening side of the inflator housing, and flows out from the opening during operation A diffuser part having a first gas discharge port for discharging the pressurized medium to the outside, and the outlet path of the pressurized medium between the opening part of the inflator housing and the diffuser part is blocked by a rupture disk, Furthermore, the diffuser part is an inflator provided with means for breaking the rupturable plate,
A part or substantially all of the outer surface of the diffuser is covered with a cap ,
The breaking means provided in the diffuser part has an igniter, a connector connected to the igniter, and a lead wire connected to the connector, and is pressed and supported by the inner surface of the cap and the outer surface of the diffuser part. The inflator with a cap by which the extending | stretching direction of a lead wire is controlled by .   The inflator with a cap according to claim 1, wherein the cap is made of an elastic member, and a part or substantially all of the outer surface of the diffuser portion is covered with the cap pressed from the outside.   The cap has an opening serving as a second gas discharge port, the second gas discharge port communicates with the first gas discharge port of the diffuser portion, and the pressurized medium ejected from the first gas discharge port is the second gas discharge port. The inflator with a cap according to claim 1, which is ejected from a gas discharge port. The outer surface of the diffuser portion has an uneven portion, the portion facing the uneven portion of the inner surface of the cap, claim 1-3 having an uneven portion that corresponds to the uneven portion 1 Inflator with cap as described. The inflator with a cap according to any one of claims 1 to 4 , wherein the breaking means provided in the diffuser portion is attached in parallel or coaxially with the central axis of the inflator housing. The inflator with a cap according to any one of claims 1 to 5 , wherein an extending direction of the lead wire is an inflator housing side direction. The inflator with a cap according to any one of claims 1 to 6, wherein the extended lead wire does not overlap the first gas exhaust port of the diffuser part and the second gas exhaust port of the cap. An air bag apparatus comprising: an operation signal output means comprising an impact sensor and a control unit; and a module case in which the inflator with a cap according to any one of claims 1 to 7 and an air bag are accommodated in the case. An assembly method of an airbag apparatus comprising: an operation signal output means comprising an impact sensor and a control unit; and a module case in which the inflator with a cap according to any one of claims 1 to 7 and an airbag are housed in the case. And, when connecting the inflator and the airbag, cover the cap covering the part or substantially the entire outer surface of the diffuser portion of the inflator and cover the opening of the airbag with a string-like fastening means. An assembly method for an airbag device that fastens and fixes an airbag. A groove is formed around the outer surface of the cap that covers the diffuser portion, and the opening of the airbag is covered so as to cover at least the groove, and the string-like fastening means is in contact with the groove and tightened. 9. Assembly method of 9 airbag devices.

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