JP2009006918A - Inflator - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an inflator for an occupant restraining device of an automobile easy to mount a rupture disk for enclosing gas, and its assembling method. <P>SOLUTION: The rapture disk 19 processed beforehand to be in a shape having a spherical surface is contacted by an annular corner 52 which is to be a mounting part to form a loop line, and resistance-welded in this status. As the spherical surface of the rapture disk 19 line-contacts the mounting part, improvement of the processing accuracy in the mounting part is unnecessary and the resistance welding is easily done. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an inflator for a vehicle personnel restraint device with an improved method of attaching a rupturable plate and an assembling method thereof.

  Inflator that uses pressurized gas is installed outside the vehicle to protect driver and passenger airbags, side impact airbag devices, curtain airbag devices, knee bolster devices, inflatable seat belt devices, and pedestrian protection. It is used for a personnel restraining device of a vehicle such as a device to be used.

  In such an inflator, since the gas is sealed inside the bottle, the opening is closed with the rupturable plate. However, since the gas needs to be sealed during the service life of the vehicle (for example, 10 years), the rupturable plate Installation is important. Conventionally, it takes time and effort to smooth the mounting surface or to increase the dimensional accuracy.

  Patent Document 1 is an invention of an air bag gas generator (inflator) using pressurized gas. The inflator housing 12 is filled with pressurized gas, and in order to close the outflow path 18, a bowl-shaped rupturable plate 19 is attached. The rupture disc 19 has its peripheral edge fixed to the peripheral edge portion 19a of the diffuser portion 20 by resistance welding. The bowl-shaped rupturable plate 19 is a flat plate before being attached, and after fixing to the peripheral edge portion 19a, it is shaped like a bowl as shown in FIG. 2 by the pressure of the pressurized gas filled into the inflator housing 12 through the pores. It is deformed.

The peripheral edge portion 19a to which the rupturable plate 19 is attached needs to have a smooth surface in advance so that the pressurized gas does not leak after the rupturable plate 19 is fixed. In particular, when resistance-welding the rupturable plate 19 to the peripheral portion 19a, it is important to increase the processing accuracy of the peripheral portion 19a. In addition, since the alignment for fixing the rupturable plate 19 without deviation with respect to the peripheral edge portion 19a becomes strict, there is also the complexity of assembly.
JP 2003-182506 A

  It is an object of the present invention to provide an inflator for a vehicle personnel restraint device and a method for assembling the same, in which attachment of a rupturable plate for enclosing gas is simplified.

[Claim 1]
The invention of claim 1 is a solution to the problem.
An inflator for a vehicle personnel restraint device having a bottle filled with pressurized gas, wherein the airtightness inside the bottle is maintained by closing the opening of the bottle with a rupturable plate Yes,
An inflator is provided in which the rupturable plate is formed in advance so as to have a spherical surface, and the spherical surface is fixed in a state where the spherical surface is in contact with a mounting portion with a line.

  As the rupturable plate, one formed in advance so as to have a spherical surface is used. For example, a shape obtained by cutting a true sphere at a desired portion (for example, a hemisphere) can be used. The rupturable plate having such a spherical surface can be obtained by press-molding a circular plate, or may be directly formed by a hemisphere or the like.

  The attachment portion of the rupturable plate is the opening peripheral portion of the bottle or the opening peripheral portion of the other member connected to the bottle opening. The attachment portion may be a flat surface, a slope, a convex curved surface, or may have a corner. In the present invention, if the attachment portion is a concave surface, particularly a concave surface corresponding to the spherical surface of the rupturable plate, the contact portion with the rupturable plate becomes a surface and it is difficult to fix by resistance welding.

  When the spherical surfaces of the rupturable plate are brought into contact with each other so as to press against a flat surface, a slope, a convex curved surface, or a corner, the portions that are in contact with each other are not lines but lines. When resistance welding is performed, if the area of the contact portion is large, the current flow is good and welding becomes difficult. For this reason, conventionally, the processing accuracy of the mounting portion is increased (specifically, the mounting portion is processed into a clean convex curved surface) so that the area of the contact portion between the mounting portion and the disc-shaped rupturable plate is reduced. However, in the present invention, since the attachment portion and the rupturable plate can be brought into contact with each other with a line, it is not necessary to increase the processing accuracy of the attachment portion, and fixing by resistance welding is facilitated.

  Conventionally, as disclosed in Patent Document 1, the disc-shaped rupturable plate is deformed into a bowl shape by the pressure of the pressurized gas, so that the positioning of the mounting position of the disc-shaped rupturable plate is strict. It was necessary. However, if the rupturable plate is formed in advance so as to have a spherical surface, the spherical surface only needs to come into contact with the mounting portion. Become.

[Claim 2]
The invention of claim 2 is a solution to the problem.
An igniter housing containing ignition means is connected to the opening of the bottle whose one end is open, the opening is closed by a rupturable plate, and the bottleneck is filled with pressurized gas. An inflator for the device,
Provided is an inflator in which the rupturable plate is formed in advance so as to have a spherical surface, and is fixed in a state where the spherical surface is in contact with the igniter housing or the bottle as an attachment portion on the spherical surface. To do.

  Similarly to the first aspect of the invention, it is not necessary to increase the processing accuracy of the attachment portion of the rupturable plate, resistance welding is facilitated, and attachment work is facilitated.

[Claim 3]
The invention of claim 3 is a solution to the problem.
An igniter housing in which ignition means is accommodated is connected to an opening on one end side of a bottle that is open at both ends, and a diffuser having a gas discharge port is connected to an opening on the other end side. An inflator for a vehicle personnel restraint device closed with a rupturable plate and filled with pressurized gas inside the bottle;
The rupturable plate is formed in advance so as to have a spherical surface, and in the spherical surface, the igniter housing or the bottle serving as the attachment portion and the diffuser or the bottle serving as the attachment portion are in contact with a line. An inflator is provided that is secured in a state where

  Similarly to the first aspect of the invention, it is not necessary to increase the processing accuracy of the attachment portion of the rupturable plate, resistance welding is facilitated, and attachment work is facilitated.

[Claim 4]
According to a fourth aspect of the present invention, as the means for solving the problem, the mounting portion is a corner portion formed in an annular shape, the corner portion and the spherical surface of the rupturable plate are in contact, and the corner portion and the spherical surface are in contact with each other. An inflator for a vehicle personnel restraint device according to any one of claims 1 to 3, wherein the inflator is fixed at an annularly contacting portion.

  Similarly to the first aspect of the invention, since it is not necessary to increase the processing accuracy of the attachment portion of the rupturable plate, the attachment portion can be formed into a corner portion formed in an annular shape. Therefore, resistance welding may be performed in a state where the rupture disc having a spherical surface is pressed against the corner portion and brought into contact with the corner portion, and the mounting operation is simplified.

[Claim 5]
According to a fifth aspect of the present invention, as the means for solving the problem, the attachment portion is a conical inclined surface whose shape in the axial cross section of the inflator extends in the bottle center direction, and the spherical surface of the rupturable plate is formed on the conical inclined surface. An inflator for a vehicle personnel restraint device according to any one of claims 1 to 3, wherein the inflator is in contact with each other and is fixed at a portion where the inclined surface and the spherical surface contact in an annular shape.

  Similarly to the first aspect of the invention, since it is not necessary to increase the processing accuracy of the attachment portion of the rupturable plate, the attachment portion can be a conical space. Therefore, it is only necessary to perform resistance welding in a state where a rupture disk having a spherical surface is pressed against the conical inclined surface, and the mounting operation is simplified.

[Claim 6]
The invention of claim 6 is a means for solving another problem.
An inflator assembly method for a vehicle personnel restraint device according to any one of claims 1 to 5, wherein the rupturable plate is formed by resistance welding in a state where the mounting portion and the spherical surface of the rupturable plate are in contact with each other. A method for assembling an inflator is provided, which includes a step of adhering to the attachment portion.

  Since a rupturable plate having a spherical surface is used, when the rupturable plate is pressed against the attachment portion, the rupturable plate and the attachment portion come into contact with each other with a line. For this reason, there is no need to increase the processing accuracy of the mounting portion as in the case of using a disc-shaped rupture disc, and resistance welding is facilitated. In addition, exact alignment as in the case of using a disc-shaped rupture disk is not required.

  Since the inflator of the present invention uses a rupturable plate having a spherical surface, it is easy to attach the rupturable plate.

(1) Inflator of FIG. 1 FIG. 1 is a sectional view in the axial direction of an inflator 10 of the present invention. The bottle 12 has an opening on one end side and is closed on the other end side. The internal space 16 is filled with an inert gas such as argon or helium at a high pressure (for example, about 70,000 kPa).

  A diffuser unit 20 is connected to the opening side of the bottle 12. The diffuser unit 20 has a first gas discharge port 22 through which the pressurized gas flows out. The bottle 12 and the diffuser part 20 are connected by welding.

  A gas passage 18 formed in the diffuser portion 20 is closed with a rupturable plate 19 that has been processed into a shape having a spherical surface in advance. The rupturable plate 19 closes the gas passage 18 in the diffuser part 20 to maintain the internal space 16 of the bottle 12 in a high-pressure airtight state until the operation.

  An igniter 26 is disposed in the diffuser unit 20. The igniter 26 is arranged so that the operating portion 26 a faces the rupturable plate 19. The igniter 26 is fitted in a direction from the one end opening of the diffuser portion 20 toward the rupturable plate 19, and is fixed by caulking the peripheral edge 28 of the one end opening of the diffuser portion 20.

  The igniter 26 is an electric igniter, and the operating portion 26a is filled with a heating element that is red-hot by current and a known ignition agent that is ignited by the heating element. When the igniter 26 is ignited, the rupture plate 19 is pressed by a combustion product (flame, high-temperature gas, shock wave, etc.) generated from the operating portion 26a, ruptures or drops off, and the gas passage 18 is opened.

  A gas exhaust port 30 is connected to the diffuser unit 20. Specifically, the pressurized gas inflow portion 32 of the gas exhaust port 30 is inserted into the first gas exhaust port 22 of the diffuser portion 20 and then connected by welding. The central axis of the gas discharge port 30 (the one-dot chain line in the length direction in FIG. 1) is parallel to the central axis (the one-dot chain line in FIG. 1) of the pressure bottle 12.

  The gas discharge port 30 has a plurality of second gas discharge ports 35 formed on the closed end face 34 side. At least two of them are arranged at positions that are symmetrical to each other in the width direction or at positions that approximate to them.

  Next, a method for manufacturing the rupturable plate 19 that has been processed into a shape having a spherical surface in advance and a method for attaching the same will be described.

[Manufacture of Rupture Plate 19 with Spherical Surface]
The manufacturing method of the rupturable plate 19 having a spherical surface will be described with reference to FIG. FIG. 2 is a process diagram for explaining a method of forming a rupturable plate used in the present invention.

  In the step (a), a stainless steel disc 19a punched to a predetermined size is placed on the concave spherical surface of the lower mold 40.

  In the step (b), the upper plate 41 is pressed against the disc 19 a placed on the lower plate 40. The convex spherical surface 41a of the upper mold 41 is processed so as to form a true spherical surface by combining with the concave spherical surface 40a of the lower mold.

  In the step (c), the rupturable plate 19 that is removed from the mold and processed into a spherical shape is obtained. The rupturable plate 19 has a shape obtained by cutting a true sphere at a desired position.

[Attachment method-1 of rupturable plate 19]
A method of attaching the rupturable plate 19 will be described with reference to FIG. (A) is an axial sectional view showing a state before the rupturable plate 19 is attached, and (b) is an axial sectional view showing a state in which the rupturable plate 19 is pressed against the attaching portion or a state after resistance welding.

  The rupturable plate 19 is attached in the diffuser part 20 (the igniter 26 is not attached and the bottle 12 and the diffuser part 20 are not connected).

  The inner wall surface forming the gas passage 18 serving as the gas flow path inside the diffuser housing 21 of the diffuser portion 20 has an inner peripheral surface portion 51 and a peripheral annular corner portion 52, and the annular corner portion 52 is formed on the rupturable plate 19. It becomes a mounting part. The inner diameter A of the inner peripheral surface portion 51 is smaller than that of the adjacent portion. The angle shown in the drawing of the annular corner 52 is about 90 °.

  The rupturable plate 19 is pressed against the annular corner 52 while being supported by an appropriate jig. At this time, the contact surface between the spherical surface of the rupturable plate 19 and the annular corner 52 is an annular line. The diameter B of the rupturable plate 19 is 1.3 times as large as the diameter A.

  When resistance welding is performed with current flowing in this state, the current flows through the narrow contact portion, so that the contact portion can easily generate heat. In the contact portion, the spherical surface of the rupturable plate 19 and the annular corner portion 52 are annular. It is fixed to.

  When the rupturable plate 19 is pressed against the annular corner portion 52, the center of the rupturable plate 19 and the center of the gas passage 18 are made to coincide with each other. Since the contact portion of the portion 52 is always an annular line, there is no influence on resistance welding, and there is no influence on the maintenance of the airtightness of the bottle 12. For this reason, alignment is easy and workability is improved.

[Attachment method-2 of rupturable plate 19]
With reference to FIG. 4, another method for attaching the rupturable plate 19 will be described. (A) is an axial sectional view showing a state before the rupturable plate 19 is attached, and (b) is an axial sectional view showing a state in which the rupturable plate 19 is pressed against the attaching portion or a state after resistance welding.

  In the diffuser part 20 (the igniter 26 is not attached and the bottle 12 and the diffuser part 20 are not connected), the rupturable plate 19 is attached.

  The inner wall surface forming the gas passage 18 serving as the gas flow path inside the diffuser housing 21 of the diffuser portion 20 has an inner peripheral surface portion 61 and a conical slope portion 62 extending from the inner peripheral surface portion 61 toward the center of the bottle 12. The conical slope portion 62 is an attachment portion for the rupturable plate 19. The inner diameter A of the inner peripheral surface portion 61 is smaller than the adjacent portion.

  The rupturable plate 19 is pressed against the conical slope portion 62 serving as a mounting portion while being supported by an appropriate jig. At this time, the contact surface between the spherical surface of the rupturable plate 19 and the conical slope portion 62 is an annular line. The diameter B of the rupturable plate 19 is 1.3 times as large as the diameter A.

  When resistance welding is performed with current flowing in this state, the current flows through the narrow contact portion, so that the contact portion can easily generate heat. It is fixed in an annular shape.

  When the rupturable plate 19 is pressed against the conical slope portion 62, the center of the rupturable plate 19 and the center of the passage 18 coincide with each other. Even if the two centers are slightly shifted, the spherical surface of the rupturable plate 19 and the conical shape are formed. Since the contact portion of the slope portion 62 is always an annular line, there is no influence on resistance welding, and there is no influence on the maintenance of the airtightness of the bottle 12. For this reason, alignment is easy and workability | operativity becomes good.

(2) Inflator in FIG. 5 FIG. 5 is a sectional view in the axial direction of an inflator 100 according to another embodiment of the present invention. The inflator 100 includes a pressurized gas chamber 120, a gas generator 130, and a diffuser unit 150.

  The pressurized gas chamber 120 has an outer shell formed of a bottle 122 having both ends opened, and is filled with argon or helium alone or a mixed gas thereof at a high pressure.

  The gas generator 130 includes an electric igniter 134 and a gas generating agent 136 housed in a gas generator housing 132, and is connected to one end opening side of the bottle 122 by resistance welding.

  A first communication hole 138 between the bottle 122 and the gas generator housing 132 is closed with a first rupturable plate 140. The first rupturable plate 140 is fixed to the attachment portion 148 formed in the gas generator housing 132 by resistance welding as shown in FIG. The first rupturable plate 140 may be fixed as shown in FIG.

  A diffuser portion 150 having a gas discharge hole 152 for discharging pressurized gas and combustion gas is connected to the opening on the other end side of the bottle 122. The diffuser portion 150 and the bottle 122 are connected by resistance welding. . Further, a cap 144 is attached so as to cover the first rupturable plate 140.

  The second communication hole 156 between the bottle 122 and the diffuser part 150 is closed with a second rupturable plate 158. The second rupturable plate 158 is fixed to the attachment portion 160 formed in the diffuser portion 150 by resistance welding as shown in FIG. The second rupturable plate 158 may be fixed as shown in FIG.

The axial sectional view of the inflator of the present invention. Explanatory drawing of the manufacturing method of the rupture disk used in FIG. Explanatory drawing of the attachment method of the rupture disk in the inflator of FIG. Explanatory drawing of the attachment method of the rupture disk in the inflator of another embodiment. The axial direction sectional view of the inflator of another embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Inflator 12 Bottle 18 Gas passage 19 Rupture plate 20 Diffuser part 21 Diffuser housing 51 Inner peripheral surface part 52 Annular corner part 61 Inner peripheral surface part 62 Conical slope part

Claims (6)

An inflator for a vehicle personnel restraint device having a bottle filled with pressurized gas, wherein the airtightness inside the bottle is maintained by closing the opening of the bottle with a rupturable plate Yes,
An inflator in which the rupturable plate is formed in advance so as to have a spherical surface, and the spherical surface is fixed in a state where the spherical surface is in contact with a mounting portion with a line. An igniter housing containing ignition means is connected to the opening of the bottle whose one end is open, the opening is closed by a rupturable plate, and the bottleneck is filled with pressurized gas. An inflator for the device,
The inflator, wherein the rupturable plate is formed in advance so as to have a spherical surface, and is fixed on the spherical surface in a state of being in contact with the igniter housing or the bottle as an attachment portion with a line. An igniter housing in which ignition means is accommodated is connected to an opening on one end side of a bottle that is open at both ends, and a diffuser having a gas discharge port is connected to an opening on the other end side. An inflator for a vehicle personnel restraint device closed with a rupturable plate and filled with pressurized gas inside the bottle;
The rupturable plate is formed in advance so as to have a spherical surface, and in the spherical surface, the igniter housing or the bottle serving as the attachment portion and the diffuser or the bottle serving as the attachment portion are in contact with a line. Inflator that is fixed in the state of   The mounting portion is a corner portion formed in an annular shape, the corner portion and a spherical surface of the rupturable plate are in contact with each other, and the corner portion and the spherical surface are fixed at a portion in contact with the annular shape. The inflator for the personnel restraint apparatus of the vehicle of any one of 1-3.   The mounting portion is a conical inclined surface whose shape in the axial cross section of the inflator extends in the bottle center direction, the spherical surface of the rupturable plate is in contact with the conical inclined surface, and the inclined surface and the spherical surface are annular The inflator for a personnel restraining device for a vehicle according to any one of claims 1 to 3, wherein the inflator is fixed at a portion in contact with the vehicle. An inflator assembly method for a vehicle personnel restraint device according to any one of claims 1 to 5, wherein the rupturable plate is formed by resistance welding in a state where the mounting portion and the spherical surface of the rupturable plate are in contact with each other. A method for assembling an inflator, including a step of adhering to the attachment portion.

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