JP2002211342A - Air bag door and air bag door molding method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make an air bag door strong in shock and to exactly form a thin-walled fracture predetermined part. SOLUTION: The air bag door with the thin-walled fracture predetermined part formed in a door part is injection-molded by injecting a resin material R into a cavity 29 in a retreated state of a first slide core 31, advancing a first slide core 31 by substantially synchronizing with termination of injection and retreating a second slide core 35.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an airbag door and a method of forming an airbag door, the door portion of which is opened by an airbag deployment pressure of an airbag device mounted on a vehicle.

[0002]

2. Description of the Related Art For example, Japanese Patent Application Laid-Open No.
-22821 (hereinafter referred to as Conventional Example 1) and JP-A-11-301398 (hereinafter referred to as Conventional Example 2)
As disclosed in Japanese Patent Application Laid-Open Publication No. H11-163, there is known an airbag door in which a thin-wall rupture portion is formed in a door portion, and the thin-wall rupture portion is broken by the deployment pressure of an airbag that deploys during a vehicle collision, and the door portion opens. Have been. And these conventional examples 1,
In both cases, a portion along the portion to be thinly broken is formed to be thicker than the thickness of the general portion surrounding the portion over a predetermined width to reinforce around the portion to be thinly broken.

[0003]

By the way, since the deployment pressure of the airbag acts instantaneously on the airbag door, measures are taken to prevent the door from scattering due to the impact of the deployment of the airbag. Thoroughness is required for safety.

In the method of molding an airbag door of the above-mentioned prior art example 1, when a resin material is injection-molded using a pair of molding dies, a mold projection for forming a thin-wall breakable portion in one molding die. Is projected into the cavity, and the distance between the mold protrusion at the relevant location and the molding surface of the other mold is very small, so that the resin material does not easily pass over the mold protrusion and spread over the entire cavity, and is thin. Undercutting occurs in the portion to be broken, and the thin portion to be broken cannot be accurately formed.

[0005] On the other hand, in the method of molding the airbag door of Conventional Example 2, a resin material is injected from separate gates on both sides of a mold projection. In this case, in order to accurately form the thin-wall fracture expected portion, the resin material on both sides of the mold protrusion merges at the tip of the mold protrusion, or the resin material on one side climbs over the mold protrusion and the resin material on the other side. In any case, it is difficult for the resin material to flow into the tip end portion of the mold projection portion having a narrow interval, and it is difficult to accurately form the thin-wall breakable portion because the thin-wall breakable portion is underfilled.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and an object of the present invention is to provide an airbag door that is resistant to impact and to accurately form a thin-wall breakable portion.

[0007]

SUMMARY OF THE INVENTION In order to achieve the above-mentioned object, the present invention is to increase the thickness of a door portion and to make the distance between cavity portions corresponding to a portion to be broken thin during molding. It is characterized by.

More specifically, the invention as set forth in claim 1 is characterized in that a resin material is injected and molded to form a concave portion on the back surface to form a thin-walled rupture portion, and the thin-walled rupture portion is deployed in an airbag. An airbag door made of a core material that is broken by pressure to open a door portion, wherein the thickness of the door portion is formed to be thicker than the thickness of the entire outer periphery of the door portion. And

According to the above construction, in the invention according to the first aspect, the entire door portion is thickened and reinforced, and even if the thin-walled rupture portion is broken by an instantaneous strong deployment pressure of the airbag, The rupture does not affect the periphery of the thin-wall rupture scheduled portion, and the door does not scatter.

According to a second aspect of the present invention, there is provided a core material in which a concave portion is formed on the back surface to form a thin-walled rupture portion, and the thin-wall rupture portion is broken by an airbag deployment pressure to open the door portion. The following solutions were taken for an airbag door molding method for injection molding an airbag door comprising:

That is, the invention according to claim 2 provides one molding die for forming the front surface side of the door portion, another molding die for forming the rear surface side of the door portion, and one molding die and the other molding die. A first slide core that is provided on the other mold side so as to advance and retreat with respect to a cavity formed between the mold and the recess, thereby forming the thin-walled break-predicted portion; A second slide core which is provided adjacent to the first slide core on the other mold side so as to advance and retreat with respect to the second slide core and sets a thickness of the door portion; The resin material is injected into the cavity with the slide core retracted, and the first slide core is advanced and the second slide core is retracted substantially in synchronization with the end of the injection of the resin material, whereby the thin wall is formed. The airbag door sectional scheduled portion is formed, characterized in that injection molding.

According to the second aspect of the present invention, when the resin material is injected, the first slide core, which forms the thin-walled breakable portion by forming the concave portion, retreats when the resin material is injected. Since the space between the cavities is wide, the flow of the resin material does not hinder the flow, and the resin material spreads evenly and smoothly over the entire cavity. From this state, the first slide core advances almost in synchronization with the end of the injection of the resin material, so that the thin-walled scheduled portion is accurately formed. At this time, the second slide core is retracted, and an amount of resin material corresponding to the amount of advance of the first slide core flows into the cavity portion expanded by the retraction of the second slide core. It does not hinder molding.

According to a third aspect of the present invention, in the second aspect of the present invention, the thickness of the door portion is formed so as to be thicker than the thickness of the entire outer periphery of the door portion. I do.

According to the third aspect of the present invention, an airbag door having a thick wall as a whole is injection-molded.

According to a fourth aspect of the present invention, in the second aspect of the invention, the portion along the thin-wall breakable portion of the door portion is thicker than the general portion of the door portion over a predetermined width. It is characterized by being formed in.

According to the above configuration, according to the fourth aspect of the invention, an airbag door different from that of the third aspect is obtained. In this airbag door, a portion extending over a predetermined width along the thin-walled rupture portion is thickened and reinforced, and even if the thin-wall rupture portion is ruptured by an instantaneous strong deployment pressure of the airbag, the rupture does not occur. Does not affect the outer periphery of the thin-wall fracture planned portion. The strength of the portion other than the thick portion can be dealt with by forming a reinforcing rib on the back surface of the door portion.

According to a fifth aspect of the present invention, in the second aspect of the present invention, the thickness of the door portion is substantially the same as the thickness of the outer periphery of the door portion over the entirety. I do.

According to the fifth aspect of the present invention, an airbag door different from the third and fourth aspects is obtained. The strength of the airbag door is also supplemented by forming the reinforcing ribs as described in claim 4.

[0019]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 5 shows the front part of the passenger seat of the instrument panel 1 of the vehicle. In this example, an airbag device 7 (see FIG. 4) described later is a front airbag device arranged in front of a passenger seat on the side of a driver's seat.
Is designed to protect an occupant from a shock from the front and rear direction of the vehicle, but can be applied to a pad of a steering handle to protect a driver. In addition, the present invention can also be applied to a case where an airbag device 7 is provided in a vehicle interior component such as a center pillar garnish. The airbag device 7 is a so-called seamless type in which a mounting position is not known from the outside.

The instrument panel 1 has a single-layer structure formed by injecting a resin material, and as shown in FIG. 4, an instrument panel main body made of a resin core material whose entire surface is exposed to the vehicle interior. 3 is provided. On the back surface of the instrument panel body 3 where the airbag device 7 is mounted, two mounting plates 5 are protruded at an interval in the vehicle front-rear direction, and the airbag device 7 is mounted on the two mounting plates 5. It is installed.

The airbag device 7 has an airbag case 13 in which the folded airbag 9 and the inflator 11 are housed, and the airbag case 13 is provided with the engagement holes 5 a of the two mounting plates 5. The locking claw 15a of the locking plate 15 is engaged with the
The airbag device 7 is disposed on the back surface of the instrument panel body 3.

The instrument panel body 3
A concave portion 17 having a V-shaped cross section is formed on the back surface of the mounting position of the airbag device 7, thereby forming a thin-walled breakable portion 18 that breaks by the deployment pressure of the airbag 9 and is thinner than the general portion. It constitutes a thin fragile part. As shown by a broken line in FIG. 5, the thin-wall planned break portion 18 includes a transverse break planned portion 18a extending in the vehicle width direction and the transverse break planned portion 18a.
And two longitudinally rupturable portions 18b extending in the vehicle front-rear direction from both ends thereof are formed in a horizontally long H shape in plan view.

Further, the door portion 21 at the base end of the two mounting plates 5 has a section V which is shallower than the recess 17.
A U-shaped recess 19 is formed, which allows the hinge 20
Each of the concave portions 19 forming the hinge portions 20 is provided with a concave portion 17
The two longitudinally fractured portions 18b of the concave portion 17b are formed at two locations on both ends in the vehicle front-rear direction and extend linearly and parallel to the vehicle width direction,
The vehicle front ends and the vehicle rear ends of the concave portions 17b forming the longitudinal break portions 18b are connected to each other (see a dashed line in FIG. 5).

In the instrument panel body 3, a front door portion 21 a and a front door portion 21 a are provided in the instrument panel body 3 in a rectangular area surrounded by a thin-wall breakable portion 18 indicated by a broken line in FIG. 5 and a hinge portion 20 indicated by a dashed line. A door portion 21 including a rear door portion 21b is formed, and the door portion 21 and the two mounting plates 5 constitute an airbag door 22 according to an embodiment of the present invention.

Therefore, in this example, when the vehicle collides, the airbag 9 is deployed by the operation of the inflator 11, and the thinned portion 18 to be broken is broken by the deployed pressure, so that the door portion 21 of the airbag door 22 is closed. The front door portion 21a and the rear door portion 21b open upward and downward in the vehicle front-rear direction around two hinge portions 20 in the vehicle front-rear direction.

One of the features of the present invention is that the thickness t1 of the door portion 21 of the airbag door 22 is thicker than the thickness t2 of the instrument panel body 3 around the door portion 21 over the entirety. Is formed.

As a result, the entire door portion 21 can be reinforced by the thick portion, and even if the thin break portion 18 is broken by the instantaneous strong deployment pressure of the airbag 9, the effect of the break is reduced by the thin break. The airbag door 22 can be prevented from reaching the outer periphery of the scheduled portion 18, and the scattering of the door portion 21 of the airbag door 22 can be reliably prevented.

The airbag door 21 as described above is injection-molded by a molding device 23 shown in FIGS.

The molding device 23 is provided with the airbag door 22.
The fixed mold 25 as one forming mold that forms the front side of the instrument panel body 3 including the door section 21 of the airbag door 22 and the other that forms the back side of the instrument panel body 3 including the door section 21 of the airbag door 22. A movable mold 27 is provided as a molding die, and a cavity 29 is formed between the molding surfaces 25a, 27a when the fixed mold 25 and the movable mold 27 are closed. The interval c1 corresponds to the thickness t2 of the instrument panel main body 3.

As shown in FIG. 3, a first slide core 31 is formed on the movable die 27 side, in which a concave portion 21 is formed on the back surface of the door portion 21 to form a thin breakable portion 18 of the airbag door 21. Are arranged, and the first slide core 31
The horizontal core portion 31a
The vertical core portion 31b is formed into a horizontally long H shape in plan view. At the tip (lower end) of the first slide core 31, a sharp tip portion 31c having a triangular cross section is formed corresponding to the V-shape of the thin-walled breakable portion 18.
Further, two points where the horizontal core portion 31a and the vertical core portion 31b of the first slide core 31 intersect are respectively connected to tips of piston rods 33a extending below the two first fluid pressure cylinders 33. The first hydraulic cylinder 33 is supported by the movable mold 27 via a holder (not shown). And these two first hydraulic cylinders 33
The first slide core 31 advances and retreats with respect to the cavity 29 by the synchronized expansion and contraction operation, and in the advanced state, the sharpened end 31c approaches the molding surface 25a of the fixed mold 25, and the distance c2 between the two becomes extremely narrow ( (See Fig. 1 two-dot chain line and Fig. 2)
On the other hand, in the retracted state, the pointed tip portion 31c is separated from the molding surface 25a of the fixed mold 25, and the distance c3 between the two is set to the both molding surfaces 25a.
The distance c is wider than the distance c1 between the first and second a (see the solid line in FIG. 1).

On the movable mold 27 side, a second slide core 35 composed of two rectangular blocks for setting the thickness t1 of the door portion 21 of the airbag door 22 is provided laterally of the first slide core 31. Core part 31a and vertical core part 31b
Are arranged adjacent to the first slide core 31 so as to be surrounded by the first slide core 31, and the second slide cores 35 each extend below the second fluid pressure cylinder 37.
Each of the second fluid pressure cylinders 37 is connected to the distal end, and is supported by the movable mold 27 via a holder (not shown). Then, the two second slide cores 35 are driven by the synchronized expansion and contraction of the two second hydraulic cylinders 37.
Moves forward and backward with respect to the cavity 29, and in the advanced state, the molding surface 35a is substantially flush with the molding surface 27a of the movable mold 27, and the distance c4 between the molding surface 35a and the molding surface 25a of the fixed mold 25 is fixed. Molding surface 2 of mold 25 and movable mold 27
5a and 27a are substantially equal to the interval c1 (see the solid line in FIG. 1).
So that the distance c5 between the molding surface 35a and the molding surface 25a of the fixed mold 25 is wider than the distance c1 between the molding surfaces 25a and 27a of the fixed mold 25 and the movable mold 27. (Fig. 1 two-dot chain line and Fig. 2
reference).

On the outer side of the two second slide cores 35 of the movable mold 27, vertically long recesses 39 for forming the mounting plate 5 for mounting the airbag case 13 are formed, and these vertically long recesses 39 are formed. At the end (lower end) of the side wall on the side of the second slide core 35, a projection 39a having a sharp end is formed at the base end of the mounting plate 5 to form the concave portion 19 to form the hinge portion 20 of the door portion 21. I have. The projection 39a protrudes into the cavity 29 beyond the molding surface 27a of the movable mold 27, and the distance c6 between the tip of the projection 39a and the molding surface 25a of the fixed mold 25 is fixed.
C1 between the molding surfaces 25a and 27a of the movable mold 27 and the movable mold 27
It is slightly narrower than.

The procedure for molding the airbag door 21 by the molding apparatus 23 configured as described above will be described.

First, as shown by the solid line in FIG.
, The movable mold 27 is lowered to close the mold, the first slide core 31 is retracted by the contraction operation of the first hydraulic cylinder 33, and the two second slide cores 35 are extended by the second hydraulic cylinder 37. The resin material R is injected into the cavity 29 in a state where it has advanced by the operation. In this state, the molding surfaces 35a and 27a of the second slide core 35 and the movable mold 27 are substantially flush with each other, and the distance c4 between the molding surface 35a of the second slide core 35 and the molding surface 25a of the fixed mold 25 is set. Are the molding surfaces 25 of the fixed die 25 and the movable die 27
The distance c is substantially equal to the distance c1 between the light-emitting elements a and 27a. Further, the tip sharp portion 31c of the first slide core 31 is separated from the molding surface 25a of the fixed mold 25, and the distance c between the two is set.
Reference numeral 3 denotes both molding surfaces 25a, 27 of the fixed mold 25 and the movable mold 27.
The interval c is wider than the interval c1. Further, the base end of the protrusion 39 a is not exposed to the cavity 29 due to the advance of the second slide core 35. The distance c6 between the tip of the projection 39a and the molding surface 25a of the fixed mold 25 is wider than the distance c2 between the sharpened end 31c of the first slide core 31 in the advanced state and the molding surface 25a of the fixed mold 25. , Does not hinder the flow of the resin material R.

Therefore, the injected resin material R is not disturbed by the sharpened portion 31c, and the cavity 29 is not disturbed.
It spreads smoothly throughout.

Next, as shown in the two-dot chain line in FIG. 1 and FIG. 2, the first slide core 31 is advanced by the extension operation of the first fluid pressure cylinder 33 almost in synchronization with the end of the injection of the resin material R. And the two second slide cores 35
Is retracted by the synchronized contraction operation of each second hydraulic cylinder 37. In this state, the pointed end portion 31c of the first slide core 31 is close to the molding surface 25a of the fixed die 25, and the distance c2 between them is the distance between the molding surfaces 25a, 27a of the fixed die 25 and the movable die 27. It is much narrower than c1. The molding surface 35 of the second slide core 35
a is retracted from the molding surface 27a of the movable die 27, and the distance c5 between the molding surface 25a of the fixed die 25 and the molding surface 25a of the fixed die 25 is slightly wider than the distance c1 between the molding surfaces 25a and 27a of the movable die 27. Has become. Further, the protrusion 39a
The second slide core 35 is completely exposed to the cavity 29 by retreating.

Accordingly, the recessed portion 17 is formed on the back surface of the door portion 21 by the advanced first slide core 31 to form the thin-wall breakable portion 18, and the exposed projection 39a forms the base of the mounting plate 5. An airbag door 21 in which a concave portion 19 is formed on the back surface of the door portion 21 on the end side and a hinge portion 20 is formed in the door portion 21 is injection molded. The injection molded airbag door 22
The thickness t1 of the door portion 21 is formed to be thicker than the thickness t2 of the instrument panel body 3 around the outer periphery of the door portion 21 over the entirety by the retreated second slide core 35.

As described above, when the resin material R is injected, the first slide core 3 for forming the thin-walled breakable portion 18 is formed.
1 has receded and the space c3 between the cavities 29 at the corresponding position
Is widened, the flow of the resin material R is not hindered, and the resin material R can be evenly and smoothly spread over the entire cavity 29.

Therefore, even if the first slide core 31 advances thereafter, since the resin material R has already spread over the entire cavity 29, the thin-wall breakable portion 18 can be accurately formed without interruption.

Further, when forming the thin breakable portion 18 by the first slide core 31 which advances almost in synchronization with the end of the injection of the resin material R, the second slide core 35 is retracted, and the first slide core 31 is moved. The amount of the resin material R corresponding to the advance amount of the airbag door is caused to flow into the cavity 29 expanded by the retreat of the second slide core 35, so that the door portion 21 of the airbag door 21 can be formed without any trouble. .

In the above-described embodiment, the thickness t1 of the door portion 21 is reduced over the entire instrument panel body 3.
Is formed thicker than the thickness t2 of the instrument panel main body 3 over a predetermined width at a portion along the thinned portion 18 to be broken. You may. In this case, as shown in FIG. 6 as a modification, the second slide core 35 is
8, that is, a substantially U-shape in plan view along the first slide core 31. The inner part surrounded by the second slide core 35 in FIG. 6 is a fixed molding surface of the movable mold 27. In FIG. 6, two second slide cores 35 are connected by a gate-shaped connecting member 40, and both second slide cores 35 are moved forward and backward by one second hydraulic cylinder 37.

In this case, a portion extending over a predetermined width of the door portion 21 along the portion 18 to be broken can be reinforced as a thick portion. Even if the breakable portion 18 breaks, the break does not affect the outer periphery of the thin-walled breakable portion 18. This point is the same as the above embodiment. The strength of the portion other than the thick portion can be achieved by taking measures such as forming a reinforcing rib on the back surface of the door portion 21.

Although not shown, the thickness t1 of the door portion 21 may be substantially the same as the thickness t2 of the instrument panel body 3 throughout. In this case, the second slide core 35 is attached to the molding surface 27a of the movable mold 27.
Than the resin material R
, The second slide core 35 may be retracted so as to be substantially flush with the molding surface 27 a of the movable mold 27.

Also in this case, the strength of the door portion 21 can be supplemented by forming a reinforcing rib on the back surface of the door portion 21 or the like.

In the above-described embodiment, the instrument panel 1 has a single-layer structure in which the entire surface of the instrument panel body 3 is exposed in the vehicle interior. However, as shown in FIG. It may have a three-layer structure in which the foam panel 41 and the skin 43 are laminated on the surface of the main body 3 of the main body 3 as a base material. In this case, the outer skin 4
3, a thin-walled breakable portion 43 a is formed corresponding to the thin-walled breakable portion 18 of the instrument panel body 3. In the instrument panel 1 shown in FIG. 7, the instrument panel body 3 is divided into a door base material 3a where the airbag device 7 is mounted and a panel body base material 3b around the door base material 3a. 3a airbag door 2
2 constitutes the door portion 21. That is, a rectangular opening 47 is formed in the panel body base material 3b at the place where the airbag device 7 is mounted, and the rectangular opening 47 is provided with the door base material 3a (door part 21) at the place where the airbag device 7 is mounted. Are fitted, and the locking claws 49 projecting from the door base 3a (door 21) in the vehicle front-rear direction are locked to the periphery of the rectangular opening 47 so that the door base 3a (door part) is locked. 21) is attached to the rectangular opening 47. In this case, similarly to the instrument panel 1 shown in FIG. 4, the thickness t1 of the entire door portion 21 is the same as the thickness t1 of the instrument panel body 3.
It is formed thicker than 2. Note that in FIG.
When the instrument panel 1 is formed, the rectangular opening 47 of the panel main body 3b is used to prevent leakage of the raw material.
It is a seal tape stuck over the periphery and the periphery of the door base material 3a (door part 21).

Further, in the above-described embodiment, the case where the thin-wall breakable portion 18 has a horizontally long H-shape has been described, but the present invention is not limited to this, and may be a substantially U-shape or the like. In FIG. 7,
At the place where the airbag device 7 is installed, only the door base material 3a (door portion 21) is separated from the panel main body base material 3b of the instrument panel main body 3, but the foam layer 41 and the skin 4
3 may be of a type separated from the instrument panel body 3.

[0048]

As described above, according to the first aspect of the present invention, the thickness of the door portion is formed so as to be thicker than the thickness of the outer periphery of the door portion over the entirety and reinforced. The door portion can be protected from being broken by an impact due to the deployment of the airbag.

According to the second to fifth aspects of the present invention, since the resin material is injected in a state in which the first slide core is retracted, the resin material can be smoothly and evenly spread over the entire cavity without being disturbed by the first slide core. Can be made. Further, since the first slide core is advanced and the second slide core is retracted substantially in synchronization with the end of the injection of the resin material, a thin-walled breakable portion is accurately formed in the door portion by the advance of the first slide core. be able to. On this occasion,
By retreating the second slide core, it is possible to secure a relief area for the resin material in an amount corresponding to the amount of advance of the first slide core, so that molding can be prevented.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of a molding apparatus showing a state in which a first slide core is retracted and a second slide core is advanced to inject a resin material into a cavity.

FIG. 2 is a cross-sectional view of the molding apparatus showing a state in which a first slide core is advanced and a second slide core is retracted to form a thin-walled breakable portion.

FIG. 3 is a plan view of first and second slide cores.

FIG. 4 is a sectional view taken along line IV-IV in FIG.

FIG. 5 is a perspective view showing a front portion of a passenger seat of an instrument panel provided with an airbag door.

FIG. 6 is a diagram corresponding to FIG. 3 of a modified example.

FIG. 7 is a diagram corresponding to FIG. 4 of an instrument panel to which a fitting type airbag door is applied.

[Explanation of symbols]

 Reference Signs List 9 airbag 17 recess 18 thin section to be broken 21 door 22 airbag door 23 molding device 25 fixed mold (one mold) 27 movable mold (the other mold) 29 cavity 31 first slide core 35 second slide core R Resin material t1 Thickness of door part t2 Thickness of instrument panel body

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Ritsuhiro Kamimoto 2-25-31 Kabe Minami, Asakita-ku, Hiroshima City Nishikawa Chemical Co., Ltd. F-term (reference) 3D054 AA13 AA14 BB02 BB09 BB10 FF02 FF17 4F202 AH18 CA11 CB01 CK52

Claims (5)

[Claims] 1. A core material is formed by injecting and molding a resin material to form a concave portion on a back surface to form a thin-walled rupture portion, and the thin-walled rupture portion is broken by a deployment pressure of an airbag to open a door portion. An airbag door according to claim 1, wherein the thickness of the door portion is formed so as to be greater than the thickness of the entire outer periphery of the door portion. 2. An airbag door made of a core material which is formed by forming a concave portion on the back surface to form a thin-wall breakable portion, and the thin-wall breakage portion is broken by the deployment pressure of the airbag to open the door portion. An airbag door molding method, comprising: one molding die that forms a front surface side of the door portion; another molding die that forms a back surface side of the door portion; and one molding die and the other molding die. A first slide core that is provided on the other mold side so as to advance and retreat with respect to a cavity formed between the first mold and the recess, and that forms the thin-wall fracture expected portion; A second slide core provided adjacent to the first slide core on the other mold side so as to set the thickness of the door portion, to prepare the first slide core. Retracted state The resin material is injected into the cavity, and the first slide core is advanced and the second slide core is retracted substantially in synchronization with the end of the injection of the resin material. An airbag door molding method, wherein a bag door is injection molded. 3. The airbag door molding method according to claim 2, wherein the thickness of the door portion is formed to be thicker than the thickness of the outer periphery of the entire door portion. Molding method. 4. The method of molding an airbag door according to claim 2, wherein a portion of the door portion along the portion to be broken is formed to be thicker than a general portion of the door portion over a predetermined width. An airbag door molding method, characterized in that: 5. The airbag door according to claim 2, wherein the thickness of the door portion is substantially the same as the thickness of the outer periphery of the door portion over the entirety. Molding method.