JP2910972B2 - Inflator assembly - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[Object of the invention]

[0002]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an inflator assembly for operating an impact-resistant safety system such as an air bag.

[0003]

2. Description of the Related Art Conventionally, as an inflator assembly of this type, those disclosed in Japanese Utility Model Laid-Open No. 1-144154 and Japanese Unexamined Utility Model Publication No. 3-85247 are known. Both of them have an inflator case in which a gas generating substance is accommodated and a concave portion is formed in a central portion, a primer which is disposed at the bottom of the concave portion and serves as a combustion base of the gas generating substance, and an output member which ignites the primer. It has a sensor case in which a mechanism is housed and inserted and arranged in a concave portion, and a support ring coupled to the inflator case and fixing the sensor case to the inflator case.In the former inflator assembly, the support ring is The support ring and the inflator case are connected by screwing into the inflator case, and the support ring and the sensor case are directly joined by the connection of the support ring and the inflator case to hold the sensor case on the support ring. The sensor case was fixed to the inflator case. In the latter inflator assembly, the support ring and the inflator case are connected by screwing the support ring to the inflator case, and the support ring and the sensor case are rotated to the inflator case by the connection of the support ring and the inflator case. The sensor case is fixed to the inflator case by holding the sensor case on the support ring by joining via the stopped ring.

[0004]

However, in the above-mentioned conventional inflator assembly, the support ring screwed to the inflator case and the sensor case are directly joined to hold the sensor case on the support ring. Since the sensor case is fixed to the inflator case, the sensor case can be fixed to the inflator case without play.However, when the support ring is screwed into the inflator case, the rotation between the sensor case and the support ring is performed. And the sensor case rotates together with the support ring with respect to the inflator case, and as a result, the relative positional relationship between the primer and the output member may be shifted.

In the above-mentioned conventional inflator assembly, the support case is screwed to the inflator case and the sensor case is joined to the inflator case via a ring which is prevented from rotating. Since the sensor case is fixed to the inflator case by holding it on the ring, the relative positional relationship between the primer and the output member does not shift, but the presence of the ring makes the sensor case stronger with the support ring with respect to the inflator case. The sensor case could not be pressed, and there was a possibility that the sensor case would be loosened when fixed to the inflator case.

SUMMARY OF THE INVENTION Accordingly, it is a technical object of the present invention to prevent a relative positional relationship between a primer and an output member from being shifted and to fix a sensor case to an inflator case without play. .

[0007]

Configuration of the Invention

[0008]

In order to solve the above-mentioned technical problems, the technical means taken in the present invention is an inflator in which a gas generating substance is accommodated and a concave portion is formed in a central portion and a projecting wall is formed around the concave portion. A case, a detonator disposed at the bottom of the recess and serving as a base end for burning the gas generating substance, and an impact sensing mechanism having an output member for igniting the detonator are housed, and a flange portion is provided on an outer peripheral surface inserted and disposed in the recess. And a support ring formed with a bottom wall and a peripheral wall coupled to the inflator case and fixing the sensor case to the inflator case,
An engaging portion formed on the inner peripheral surface of the protruding wall and the outer peripheral surface of the sensor case to engage the sensor case and the inflator case with the concave and convex; and the inflator case formed between the peripheral wall and the protruding wall. The sensor case is held on the support ring by coupling the support ring and the inflator case formed on the screw portion for connecting the support ring, and the support ring and the inflator case formed on the flange portion and the bottom wall. And a joint fixed to the case.

[0009]

According to the above technical means, the rotation of the sensor case with respect to the inflator case caused when the support ring is connected to the inflator case by the engagement portion is regulated, and the sensor case is controlled by the support ring by the joint portion. It will be firmly pressed against the inflator case. As a result, the relative positional relationship between the primer and the output member does not shift, and the sensor case can be fixed to the inflator case without play.

[0010]

An embodiment of the present invention will be described below with reference to the accompanying drawings.

As shown in FIGS. 1 and 2, the inflator case 1 has a disk shape having an internal space formed by fixing an upper case 1a and a lower case 1b by welding or the like. Has a case 1
A circular recess 11 having an open end is formed by a. The inner space of the inflator case 1 is formed into a ring shape by forming a concave portion 11, and the gas generating substance 2 is accommodated in the inner space.

A heat transfer material 3 is accommodated in the bottom of the concave portion 11, and a piece 4 in which a detonator 41 is exposed above the heat transfer material 3 and is exposed from an upper surface thereof is press-fitted and fixed to the upper case 1a. It is arranged. In this configuration, when the primer 41 is ignited, the flame generated by the primer 41 via the transfer material 3 is transmitted to the gas generating substance, and the gas generating substance 2 generates gas by the transmitted flame. . or,
A projecting wall 12 protruding outward is formed in the upper case 1a so as to be arranged around the concave portion 11. Engagement recesses 13 are formed at three locations on the inner peripheral surface of the protruding wall 12 at irregular intervals, and a male screw portion 14 is formed on the outer peripheral surface.

The sensor case 5 has a cylindrical shape having substantially the same diameter as the concave portion 11 and mainly includes a swingable rectangular weight 61 and a lever-shaped output member 62 having a rotatable pin portion. The shock sensing mechanism 6 having the structure is accommodated. The sensor case 5 is inserted into the recess 11 from its open end, and is disposed above the piece 4 so that the primer 5 and the hole 5a of the sensor case 5 from which the output member 62 is punched face each other. Positioning of this hole 5a with respect to the primer 41 (positioning of the sensor case 5 with respect to the piece 4)
3 and 4, a pair of protrusions 5b formed on the bottom surface of the sensor case 5 and a pair of holes 4a formed on the piece 4 are fitted and inserted.

In this configuration, when the impact sensing mechanism 6 operates and the output member 62 is driven out of the hole 5a, the output member 6
2 and the primer 41 collide, and the primer 41 is ignited. A tapered surface 5c is formed at the periphery of the bottom surface of the sensor case 5, and is formed by the tapered surface 5c, the upper surface of the piece 4, and the inner peripheral surface of the concave portion 11 when the piece 4 and the sensor case 5 are arranged in the concave portion 11. Case 1a, piece 4
Further, an O-ring 7 is provided to seal between the sensor case 5 and prevent moisture from invading, and to prevent deterioration of the primer 41 and performance deterioration due to corrosion inside the sensor case 5.
As described above, by forming the tapered surface 5c, the O-ring 7 can be removed from the concave portion 11 before the sensor case 5 is disposed in the concave portion 11.
After that, the sensor case 5 is placed in the concave portion 11 so that the O-ring 7 is automatically placed at a predetermined position to securely seal between the upper case 1a, the piece 4 and the sensor case 5. Therefore, the man-hour for assembling the O-ring 7 is reduced. Also, on the outer peripheral surface of the sensor case 5, engagement protrusions 51 are provided at irregular intervals, like the engagement recesses 13.
In addition, a flange portion 52 is formed in a radial direction, which is substantially equal to or slightly smaller than the outer peripheral surface of the protruding wall 12, and a flat surface 53 is formed in the flange portion 52. .

The support ring 8 includes a bottom wall 81 and a peripheral wall 8.
2 having a circular box shape,
Is connected to the upper case 1a so as to cover the open end of the upper case.
The inner peripheral surface of the peripheral wall 81a is substantially equal to the outer peripheral surface of the protruding wall 12, and a female screw portion 83 that can be screwed with the male screw portion 14 is formed. The bottom wall 81 has a flat surface 84 that can be joined to the flat surface 53. Further, on the outer peripheral surface of the support ring 8, as shown in FIG. 5, there is formed a mounting hole 85 into which only a dedicated tool (not shown) for connecting the support ring 8 to the upper case 1a can be mounted. ing.

Next, the assembly of this embodiment will be described.

The gas generating substance 2 is accommodated and the recess 1
The sensor case 5 in which the shock sensing mechanism 6 is accommodated in the concave portion 11 of the upper case 1a (hereinafter referred to as the inflator case 1) in which the heat transfer material 3 and the piece 4 are arranged and the O-ring 7 is placed in the inside 1 Mating convex part 51 and each engaging concave part 1
3 is inserted from the open end and arranged.

At this time, since the engaging projections 51 and the engaging recesses 13 are unequally spaced, the sensor case 5 and the inflator 5 Positioning with the case 1 is performed. Further, at this time, as described above, the O-ring 7 is arranged at a predetermined position, and the projection 5b and the hole 4a are fitted and inserted, so that the sensor case 5 and the piece 4 are positioned. Thereafter, the support ring 8 is operated with a special tool attached to the attachment hole 85 to screw the female screw portion 83 and the male screw portion 14 together, so that the support ring 8 is connected to the inflator case 1. As described above, since the support ring 8 is connected to the inflator case 1 with a special tool, disassembly by a general user who does not have the special tool is prevented. At this time, by screwing the female screw portion 83 and the male screw portion 14, the flat surface 84 is joined to the flat surface 53, and the sensor case 5 is pressed firmly against the inflator case 1. 5 is held by the support ring 8 and fixed to the inflator case 1 without play. As a result, the inflator assembly is completed. The inflator assembly is then assembled to a vehicle steering wheel (not shown). As described above, the support ring 8 is coupled to the inflator case 1 by screwing the male thread portion 51 on the inflator case 1 side with the female thread portion 83 on the support ring 8 side, and the sensor case 5 is fixed to the inflator case 1 by the support ring 8. So that
Even if the pressure caused by the ignition of the primer 41 acts on the inner peripheral surface of the recess 11, the deformation generated in the inflator case 1 is in a direction in which the screwing between the male screw portion 51 and the female screw portion 83 is strengthened. The danger that the sensor case 5 jumps out of the recess 11 due to the pressure of the ignition of the primer 41 is loosened due to the loose connection between the sensor case 5 and the inflator case 1 is avoided. At this time, the rotation of the support ring 8 with respect to the inflator case 1 for connecting the support ring 8 to the inflator case 1, that is, for screwing the male screw portion 14 and the female screw portion 83, is performed at the joint between the plane 84 and the plane 53. Therefore, the rotation is transmitted to the sensor case 5 and the sensor case 5 tries to rotate together with the support ring 8. However, the rotation of the sensor case 5 is restricted by the engagement between the engagement projection 51 and the engagement recess 13. You. Thereby, the relative positional relationship between the primer 41 and the output member 62 of the impact sensing mechanism 6 is always secured at the normal position. In addition, the engagement concave portion 13 and the engagement convex portion 51
When there is play between the sensor case 5 and the inflator case 1, the sensor case 5
However, there is a possibility that the engagement between the sensor case 5 and the piece 4 may occur as a result of the shearing force acting on the protrusion 5b due to the insertion of the hole 4a into the inflator case. Since the piece 4 is only press-fitted and fixed to 1, the piece 4 rotates together with the sensor case 5, thereby preventing the shearing force from acting on the projection 5b. Thereby, correct positioning of the sensor case 5 and the piece 4 is ensured.

In FIG. 1, reference numeral 9 indicates that the shock sensing mechanism 6 is inadvertently operated when assembling the inflator assembly or assembling the inflator assembly to the steering wheel. This is a protective cover of the safety device 10 for prevention, and is fitted and fixed to the inflator case 1 by being locked to the support ring 8 by an engaging claw 91 at the final stage of constituting an inflator assembly. This prevents the operating lever 11 of the safety device 10 from being carelessly operated when assembling the inflator assembly to the steering wheel.

As described above, the rotation of the sensor case 5 with respect to the inflator case 1 which occurs when the support ring 8 is coupled to the inflator case 1 is restricted by the engagement between the engagement protrusion 51 and the engagement recess 13. The sensor case 5 is firmly pressed against the inflator case 1 by the support ring 8 by the joint between the flat surface 53 and the flat surface 84, so that the primer case 41 is fixed during the assembling work for fixing the sensor case 5 to the inflator case 1. The sensor case 5 is fixed to the inflator case 1 without any play without causing a shift in the relative positional relationship between the sensor member 5 and the output member 62.

[0021]

According to the present invention, an engaging portion for engaging the sensor case and the inflator case is formed on the inner peripheral surface of the projecting wall of the inflator case and the outer peripheral surface of the sensor case, and the flange portion of the sensor case is formed. A joint is formed on the bottom wall of the support ring to hold the sensor case to the support ring, so that rotation of the sensor case with respect to the inflator case caused when the support ring is coupled to the inflator case by the engagement portion is restricted. Then, the sensor case is firmly pressed against the inflator case by the support ring by the joint. Thus, the sensor case can be fixed to the inflator case without play without causing a shift in the relative positional relationship between the primer and the output member.

[Brief description of the drawings]

FIG. 1 is a partial sectional view of an inflator assembly according to the present invention.

FIG. 2 is an exploded view of FIG.

FIG. 3 is a view in the direction of arrow A in FIG. 2;

FIG. 4 is a view in the direction of arrow B in FIG. 2;

FIG. 5 is a view in the direction of arrow C in FIG. 2;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Inflator case 2 Gas generating substance 5 Sensor case 6 Shock sensing mechanism 8 Support ring 11 Depression 12 Protrusion wall 13 Engagement concave part (engagement part) 14 Male screw part (screw part) 41 Detonator 51 Engagement convex part (engagement part) ) 52 Flange part 53 Plane (joining part) 62 Output member 81 Bottom wall 82 Peripheral wall 83 Female thread part (screw part) 84 Plane (joining part)

──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Kazunori Sakamoto 2-1-1 Asahi-cho, Kariya-shi, Aichi Prefecture Inside Aisin Seiki Co., Ltd. (72) Tsutomu Takeuchi 2-1-1, Asahi-cho, Kariya-shi, Aichi Prefecture Aisin Seiki Co., Ltd. (72) Inventor Ken Takamura 2-1-1 Asahimachi, Kariya City, Aichi Prefecture Aisin Seiki Co., Ltd. (72) Inventor Atsushi Onoda 1 Toyota Town, Toyota City, Aichi Prefecture Toyota Motor Vehicle Stock In-company (72) Inventor Yasunori Iwai 4-2-9 Minano, Shiminawate-shi, Osaka Maison Minamino 303 (72) Inventor Nobuyuki Katsuta 8-17-1 Fukasawa, Setagaya-ku, Tokyo (72) Inventor Shiga 1-3 Nagahata, Ochiai, Kasuga-cho, Nishi-Kasugai-gun, Aichi Prefecture Examiner, Toyoda Gosei Co., Ltd. Takushi Koyama (56) Reference JP-A-5-213149 (JP, A) Kaihei 4-55141 (JP, A) JP-A 1-144154 (JP, U) JP-A 3-85247 (JP, U) (58) Fields investigated (Int. Cl. ⁶ , DB name) B60R 21 / 26

Claims (1)

(57) [Claims] 1. An inflator case in which a gas generating substance is accommodated and a concave portion is formed in a central portion and a protruding wall is formed around the concave portion, a detonator disposed in the concave portion and serving as a combustion base end of the gas generating material, and the detonator A sensor case in which an impact sensing mechanism having an output member for igniting is housed and a flange portion is formed on an outer peripheral surface inserted and arranged in the concave portion, and the sensor case is fixed to the inflator case by being coupled to the inflator case. A support ring having a bottom wall and a peripheral wall formed thereon, an engagement portion formed on an inner peripheral surface of the protruding wall and an outer peripheral surface of the sensor case for engaging the sensor case and the inflator case with the unevenness, and the peripheral wall. And a screwing portion formed between the support wall and the inflator case, and formed on the flange portion and the bottom wall. An inflator assembly having a joint for fixing the sensor case to the inflator case by holding the sensor case on the support ring by coupling the support ring and the inflator case.