JP3506118B2 - Passenger airbag door structure - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a passenger seat airbag door structure applied to a passenger seat airbag device provided at a predetermined position on the passenger seat side of an instrument panel.

[0002]

2. Description of the Related Art There are two types of airbag doors for passenger side airbag devices: a single-open type that opens to the windshield glass side during a collision, and a double-open type that opens to both the windshield glass side and the passenger side during a collision. There is. Japanese Unexamined Patent Publication No. 10-236263 discloses a double-opening type airbag door, which is a prior art suitable for explaining the problem to be solved by the present invention, and will be briefly described below.

As shown in FIG. 13, the airbag door 152 of the passenger seat airbag device 150 is formed integrally with the instrument panel 154, and the skin 156 is formed.
And a foam layer (urethane layer) 158 and a door base material 160. On the back surface side of the skin 156, a skin-side tear line (skin-side tear portion) 162 for opening both sides of the airbag door 152 at the time of collision is formed. Correspondingly, a concave portion 164 for absorbing thermal deformation is formed on the surface side of the door base material 160 at a position facing the skin side tear line 162.

According to the above construction, when a collision occurs, the bag accommodated in the airbag case 166 in a folded state is inflated, and the inflation pressure causes the outer skin 156 of the airbag door 152 to follow the outer skin side tear line 162. It will cleave. Then, the front portion 152A of the airbag door 152 opens to the windshield glass side, and the airbag door 152
The rear part 152B opens toward the passenger seat side, and the bag expands toward the passenger seat side.

[0005]

Although not disclosed in the above publication, a door hinge portion which is the center of deployment at the time of collision is usually set on the door base material of an airbag door. For example, a V-groove is formed on the back surface of the door base material to set a thin door hinge portion.

The groove width of the V groove is about 1 mm to 2 mm, so that the door hinge portion is a hinge close to a "line". In this case, it shows a sharp performance as a development center,
When the door is deployed, the foam layer (urethane layer) located above the door hinge portion interferes with each other (that is, the foam layer is compressed against the elastic restoring force), so that the airbag door is unfolded. Further, if the resistance against this deployment operation is great, there is a possibility that the rear part of the airbag door once deployed to the passenger side pushes the bag upward due to the elastic restoring force of the foam layer (urethane layer). .

Therefore, in the case of the conventional passenger side airbag device, it is difficult to maintain the optimal deployment form of the bag due to the interference of the foam layer (urethane layer) and the spring back, and the deployment performance of the bag is impaired. It is considered to be one of the stabilizing factors.

In order to solve the above problems, it is conceivable to reduce the thickness of the door hinge portion or to add a tear line to narrow the hinge width and set the door hinge portion to have a long hinge length. , High and low temperature environment (especially,
There is concern about the scattering of the airbag door when the bag is deployed in a cold environment).

In view of the above facts, it is an object of the present invention to obtain a passenger seat airbag door structure capable of stabilizing the deployment performance of the bag without scattering the airbag door.

[0010]

The present invention according to claim 1 has a base material side tear line which is cleaved by receiving a bag inflation pressure of a predetermined value or more, and is cleaved along the base material side tear line. After that, the resin door base material that expands to both the windshield glass side and the passenger side, and the front surface side of this door base material are separated from each other and are formed corresponding to the base material side tear line. And a resin door skin having a skin-side tear line that is cleaved when the bag inflation pressure acts, and a foam layer interposed between the door skin and the door base material to integrate the two. In the passenger seat airbag door structure, the rear side tear line that defines at least the rear part of the door base material that is the portion that expands to the passenger seat side in the door base material is formed in a substantially parallel pair. Front and back Of the tear line, the pair of first tear line extensions extending from the rear ends of the pair of front-rear direction tear lines toward the inside of the door by a predetermined dimension, and the pair of first tear line extensions A pair of second members extended from the end portion toward the front of the vehicle by a predetermined dimension.
The door hinge portion sandwiched between the pair of second tear line extensions has a door hinge thin portion formed thinner than a door base general portion, and And a pair of thick-walled door hinge portions that are provided along the two-tier line extension portions and have a narrower width and are thicker than the thin-walled door hinge portions.

According to a second aspect of the present invention, there is provided an airbag door structure for a passenger seat according to the first aspect of the invention, wherein the thin portion of the door hinge is offset toward the upper side of the door from the general portion of the door base material. It is characterized by

The present invention according to claim 3 has a base material side tear line which is cleaved when subjected to a bag inflation pressure of a predetermined value or more, and the windshield glass is cleaved along the base material side tear line. Side and front passenger seat side made of resin and spaced apart from the front side of the door base material, formed corresponding to the base side tear line, and the bag inflation pressure acts. Air for a passenger seat, which is configured to include a resin door skin having a skin-side tear line that is cleaved by the above, and a foam layer that is interposed between the door skin and the door base material to integrate the two. In the bag door structure, the door hinge portion, which is the center of deployment of the rear portion of the door base material that is the portion that expands toward the passenger seat side in the door base material, separates the rear part of the door base material from the main body of the door base material. For Fragile portion for rupture is formed,
Further, it is characterized in that the door hinge portion side in the rear portion of the door base material and an airbag case for accommodating the bag or a leg portion for attaching the airbag door to the airbag case are connected by a strap.

According to the first aspect of the present invention, when the bag inflates at the time of collision, the bag inflation pressure at that time acts on the back surface of the door base material of the airbag door. When the bag inflation pressure exceeds a predetermined value, the door base material is cleaved along the base material side tear line, and the bag inflation pressure also acts on the door skin through the foam layer. Cleavage along. As a result, the airbag door
The bag is expanded to both the windshield glass side and the passenger side, and the bag bulges toward the passenger side.

In the case of the present invention, the rear side tear lines that define the rear portion of the door base material, which is the portion of the door base material that extends to at least the passenger seat side, are a pair of front-rear direction tear lines and a first tear line extension, Since it has the second tear line extension, the front-rear direction tear line, the first tear line extension, and the second tear line extension are cleaved in this order to form the door base rear portion, and the door base rear portion is The door hinges sandwiched between the pair of second tear line extensions are deployed to the front passenger seat centering on the deployment.

Here, in the present invention, the door hinge portion is the first.
Flexible because it has a door hinge thin-walled part that is formed in a band shape (composed of "planes" instead of "lines") by the tear line extension and the second tear line extension and is set thinner than the general part of the door base material. The door hinge part is configured. Therefore, the door hinge portion is easily separated from the door base material main body portion, and the rear portion of the door base material is expanded to the passenger seat side. Further, in the present invention, since the thick door hinge portion is provided along the second tear line extension portion in addition to the thin door hinge portion, the hinge width of the door hinge portion (the width of the door hinge portion in the door width direction) is reduced. Even if it is made narrower, the rigidity of both sides of the door hinge is secured. Therefore, when the door base material is split along the first tear line extension, the split can be transferred to the second tear line extension without fail (that is, the split is transferred to the second tear line extension). Without doing so, it is possible to stop it from proceeding in the extension direction of the first tier line extension. Therefore, it is possible to reliably prevent the door hinge portion from breaking and the airbag door from scattering when the door is deployed.

From the above, according to the present invention, it is possible to reduce the interference of the foamed layer (located above the door hinge portion) when the door is deployed, without scattering the airbag door when the door is deployed, and by extension, Springback after door deployment can be minimized.

According to the second aspect of the present invention, since the thin portion of the door hinge is offset to the upper side of the door than the general portion of the door base material, the thickness of the foam layer located above the thin portion of the door hinge is small. Become thin. Further, since the thin portion of the door hinge is offset to the upper side of the door than the general portion of the door base material, the substantial hinge length when the airbag door is deployed becomes longer.

According to the third aspect of the present invention, when the bag is inflated during a collision, the bag inflation pressure at that time acts on the back surface of the door base material of the airbag door. When the bag inflation pressure exceeds a predetermined value, the door base material is cleaved along the base material side tear line, and the bag inflation pressure also acts on the door skin through the foam layer. Cleavage along. As a result, the airbag door
The bag is expanded to both the windshield glass side and the passenger side, and the bag bulges toward the passenger side.

In the present invention, since the fragile portion for breaking is formed in the door hinge portion which is the center of expansion of at least the rear portion of the door base material which is the portion of the door base material that is expanded to the passenger seat side, the rear part of the door base material is When a bag inflation pressure of a predetermined value or more is received, the fragile portion is broken and the rear portion of the door base material is separated from the main body of the door base material. Further, in the present invention, since the door hinge portion side in the rear portion of the door base material and the airbag case for accommodating the bag or the leg portion for attaching the airbag door to the airbag case are connected by the strap, the strap extends. The airbag door is easily deployed. Since such a strap can be made of any material and can be set to have any width and length, it is possible to easily avoid the problem of springback due to interference of the foam layer located above the door hinge portion when the door is deployed. be able to. In other words, the springback can be minimized by the present invention described in claims 1 and 2, but the present invention is extremely effective, for example, when it is desired to reduce the springback to zero. .

[0020]

BEST MODE FOR CARRYING OUT THE INVENTION [First Embodiment] A first embodiment of a passenger seat airbag door structure according to the present invention will be described below with reference to FIGS. In these figures, the arrow FR, which is shown appropriately, indicates the vehicle front side, the arrow UP indicates the vehicle upper side, and the arrow IN indicates the vehicle interior side.

FIG. 7 is a perspective view showing the appearance of the instrument panel 10 according to this embodiment. As shown in this drawing, an airbag door 14 of a so-called top dash type passenger airbag device 12 is disposed on the top of the instrument panel 10 on the passenger side. Hereinafter, for convenience of description, a portion of the instrument panel 10 other than the airbag door 14 is referred to as an "instrument panel general portion 16".

FIG. 1 shows a longitudinal sectional structure of a passenger seat airbag device 12. As shown in this figure,
The passenger seat airbag device 12 is composed of a device main body 18 in which functional components are housed, and the airbag door 14 which normally closes an upper end opening of the device main body 18 and is deployed in the event of a collision.

The apparatus body 18 is provided with an airbag case 20 having a substantially box shape. A mounting bracket 22 is arranged at the lower end of the airbag case 20. On the other hand, a stay 26 protruding toward the vehicle rear side is attached to the high-strength instrument panel reinforcement 24 arranged with the vehicle width direction as the longitudinal direction. Then, the mounting bracket 22 is fixed to the stay 26 with a fixture such as a bolt and a nut, so that the apparatus main body portion 18 is supported by the instrument panel reinforcement 24 which is a vehicle body side component member.

An electric ignition type or mechanical ignition type substantially inflator 28 is housed inside the airbag case 20. Inside the inflator 28, an igniting agent, a transfer agent, a gas generating agent, a filter, a coolant and the like are stored. A bag 30 (see FIG. 5) that is inflated when the vehicle is suddenly decelerated is disposed around the inflator 28 in a folded state.

The instrument panel general portion 16 has a three-layer structure as described below. That is, the instrument panel general portion 16 is made of a resin (for example, PVC (polyvinyl chloride), TPO (olefin-based thermoplastic elastomer), urethane, or other soft material disposed on the vehicle interior side (windshield glass 56 (see FIG. 5) side)). A resin] instrument panel skin 32, and an instrument panel base material 34 made of a resin [a hard resin such as PP (polypropylene), PPO (polyphenylene oxide), PA (polyamide), etc.] disposed apart from the instrument panel skin 32. An instrument panel foam layer 3 made of urethane or the like filled between the instrument panel skin 32 and the instrument panel base material 34.
6 and 6. The instrument panel base material 34
A door base material 44 of the airbag door 14, which will be described later, is arranged at a predetermined portion of the above, and an opening 38 for inflating the bag 30 at the time of sudden deceleration of the vehicle is formed. A step 40 is integrally formed on the peripheral edge of the opening 38.

On the other hand, the airbag door 14 that closes the opening 38 also has the same three-layer structure as the instrument panel general portion 16, and is filled between the door skin 42 and the door base material 44 and both of them. And a door foam layer 46 that integrates the same. The airbag door 14 has an outer skin side tear line 52 and a base material side tear line 66, which will be described later.
As shown in FIG. 5, it is substantially divided into a door front part 48 that expands to the windshield glass 56 side at the time of a collision and a door rear part 50 that expands to the passenger seat side,
It constitutes a so-called double-opening type airbag door.

As shown in FIG. 6, the skin-side tear line (skin tear portion) 52 formed on the door skin 42 is formed in a substantially rectangular frame shape and corresponds to the door rear portion 50 of the airbag door 14. It is provided as a tear line to do. Since the door rear portion 50 is on the swelling side of the bag 30, it is necessary to greatly expand the door rear portion 50 at the time of a collision as shown in FIG. 5, which requires an aggressive tear line. As for the door front portion 48, setting the tear line may impair the design, and may spread to the windshield glass 56 side, so that the bulging of the bag 30 toward the passenger side is not hindered. In this embodiment, the door front portion 4 can be deployed because it can be deployed.
8 dedicated tier lines are not set. However, even if a tear line dedicated to the door front portion 48 is set, it does not matter.

Further, in the present embodiment, as shown in FIG. 1, the end portion 32A of the instrument panel skin 32 and the end portion 42A of the door skin 42 are overlapped with each other and the tip portion thereof is cut to cut the skin side tear line 52. However, it is not always necessary to rely on this configuration, and other epidermal-side tear line (epidermal cleaved portion) configurations may be adopted.

On the other hand, the door base material 44 is composed of a door base material main body portion 58 formed in a substantially flat plate shape, and a mounting leg portion 60 extending substantially vertically from the back surface of the door base material main body portion 58. It is configured. A plurality of rectangular engaging holes 62 are formed on the tip side of the mounting leg portion 60, and correspondingly, a plurality of substantially J-shaped hooks 64 are fixed to the side wall of the airbag case 20. ing. These hooks 64 have engaging holes 6
By engaging 2 with each other, the airbag door 14 is attached to the airbag case 20. When the airbag door 14 is attached to the airbag case 20, the peripheral edge portion 58A of the door base material main body portion 58 is locked to the step portion 40 of the instrument panel base material 34.

A base material side tear line 66 is set on the door base material main body portion 58. The solid line in FIG.
As indicated by broken lines, the base side tear line 66 is formed in a substantially U shape in a plan view and a rear side tear line 72 that defines a door base rear portion 68, and is formed in a substantially C shape. The door base front portion 70 is defined by a front tear line 74. Rear tear line 72
Are formed so as to substantially overlap the skin-side tear line 52 described above (see FIG. 6).

More specifically, the rear tear line 72 has a width direction tear line 72A formed along the door base material width direction and a gentle curve from both ends of the width direction tear line 72A. Pair of front-rear direction tear lines 72 formed substantially parallel to each other along the door front-rear direction.
B, a pair of first tear line extension portions 72C extended from the rear end portions of the pair of front-rear direction tear lines 72B toward the inside of the door by a predetermined dimension, and the pair of first tear line extension portions 72C.
It is configured by a pair of second tear line extension portions 72D that extend further from the inner end portion of the tear line extension portion 72C toward the vehicle front side by a predetermined dimension. The front side tear line 74 is formed starting from both ends of the width direction tear line 72A in the rear side tear line 72.

Further, as shown in FIG. 1, on both sides of the width direction tear line 72A in the door base general portion 68A, there are provided a pair of protrusions 76 projecting toward the upper side of the door along the width direction tear line 72A. It is formed integrally. Therefore, the thickness of the door foam layer 46 in the portion where the ridges 76 are formed is smaller than the thickness of the door foam layer 46 on the side of the door base material general portion 68A, and between the pair of ridges 76. The front side portion of the epidermis side tear line 52 is positioned so as to be quickly broken at the time of a collision.

Grooves 78, 8 are provided at predetermined positions on the rear surface side of the door base material 44 (positions adjacent to the bases of the mounting leg portions 60).
0 are formed respectively, and these concave grooves 78 and 80 are formed.
By forming the, the thickness of that part is reduced,
As a result, a front door hinge portion 82 serving as the deployment center of the door base material front portion 70 and a rear door hinge portion 84 serving as the deployment center of the door base material rear portion 68 are respectively formed in the event of a collision. The plate thickness of the rear door hinge portion 84 is set smaller than the plate thickness of the front door hinge portion 82.

The present embodiment is characterized by the structure of the rear door hinge portion 84, which will be described in detail below.

First, regarding the forming range, the rear side door hinge portion 84 is formed in a range sandwiched by the above-mentioned pair of second tear line extension portions 72D (a portion hatched with broken lines in FIG. 4). ing.

Next, regarding the structure, as shown in FIGS. 1 to 3 (particularly FIG. 3), the rear door hinge portion 84 has a plate thickness b1 of the door base general portion 68A. Door hinge thin portion 84A thinner than T, and plate thickness b2 provided on both sides thereof is plate thickness b1 of door hinge thin portion 84A.
It is configured as a composite with the thicker door hinge portion 84B (see FIG. 3A). The plate thickness b2 of the door hinge thick part 84B needs to be thicker than the plate thickness of the door hinge thin part 84A. How much the thickness is set depends on the ease of deployment of the door base rear part 68. It is decided in consideration. In addition, the rear door hinge portion 84 and the mounting leg portion 6
An R-shaped portion 83 having a predetermined radius of curvature is provided inside the connection portion with 0.
Is formed, and a meat scavenging portion 85 is further provided on the outer side of the shaving portion to prevent rupture during deployment.

Next, regarding the shape, the thin door hinge portion 84A has a wide rectangular shape (strip shape) with a hinge width c and a hinge length a in plan view, and the thick door hinge portion 84A.
B has a hinge width d (d ') and a hinge length a, and is a narrow rectangle along the second tear line extension 72D (FIG. 3).
(See (B)). In the present embodiment, the hinge width d of the right-side door hinge thick portion 84B and the hinge width d ′ of the left-side door hinge thick portion 84B are set equal and the thickness is also set to the same. When a hybrid inflator whose position is offset is used, it is preferable to make the plate thickness of the left door hinge thick portion 84B closer to the gas ejection port of the inflator thicker.

Next, regarding the function, it is the door hinge thin portion 84A that actually exhibits the hinge function.
The door hinge thick part 84B is the first tear line extension 72.
It functions as a stopper that prevents the opening of C from reaching the thin door hinge portion 84A and breaking the thin door hinge portion 84A. In addition, in the present embodiment, the door hinge thick portion 84B is set only at the position along the second tear line extension portion 72D, but another short door hinge thick portion 84C is provided near the middle portion in the width direction of the door hinge thin portion 84A. You may add. In this case, when the left door hinge thick portion 84B (d 'side) is present when the door is deployed, if a crack H is formed over the left hinge hinge portion 84B, it functions to stop the progress of the crack H. Further, the hinge length a is ideally set to be the same as the extension length e of the second tear line extension 72D, but it may be longer or shorter than this. However,
When the extension length e is shorter than the hinge length a, the substantial dimension of the hinge length a decreases to e.

Further, as shown in FIGS. 3A and 2, the above-mentioned thin door hinge portion 84A is offset (projected) to the upper side of the door from the general door base portion 68A. Specifically, the door hinge thin portion 84A is an inclined portion 84 that extends obliquely upward from the door base material general portion 68A.
A1 and the door base member general portion 68A from the inclined portion 84A1
And a straight portion 84A2 extending substantially parallel to the rear side of the vehicle. The inclined portion 84
In a broad sense, A1 is an element that is grasped as a "hinge extension" that extends when the door is deployed to increase the hinge length, and the straight portion 84A2 maintains "the hinge length without extending when the door is deployed. It is an element that can be understood as a "part."

Next, the operation and effect of this embodiment will be described.

At the time of a collision (during a rapid vehicle deceleration), an airbag sensor (not shown) senses this and activates the inflator 28. As a result, a large amount of gas is generated from the inflator 28 and flows into the folded bag 30. Therefore, the bag 30 is inflated, and the bag inflation pressure at that time acts on the back surface of the door base material 44 of the airbag door 14. When the bag inflation pressure exceeds a predetermined value,
The door base material 44 includes a width direction tear line 72A, a front-rear direction tear line 72B, and a base material side tear line 66.
The first tear line extension 72C and the second tear line extension 72D are cleaved in this order. When the door base material 44 is torn along the base material side tear line 66, the bag expansion pressure (pressing force) at that time also acts on the door skin 42 through the door foam layer 46, so that the door skin 42. Also tears along the frame-shaped epidermis side tear line 52. As a result, the airbag door 14 is expanded to the windshield glass 56 side in the door front part 48 and greatly expanded to the passenger seat side in the door rear part 50. As a result, the bag 30
Bulges toward the passenger side. When the bag 30 is inflated, as shown by the solid line in FIG. 5, the bag 30 is inflated downward so as to cover the range from the head of the occupant seated in the passenger seat to the abdomen / waist, and the occupant is seated. Protect.

By the way, in the present embodiment, the rear tear line 72 which defines the door base rear portion 68 includes the width direction tear line 72A, the front-rear direction tear line 72B, the first tear line extension portion 72C, and the second tear line extension. Part 72D
Since it is composed of four types of elements, when it is cleaved, it is cleaved in this order to form the door base rear portion 68. Then, the door base rear portion 68 has a rear door hinge portion 84 sandwiched between the pair of second tear line extension portions 72D.
Is deployed to the front passenger seat.

Here, in this embodiment, the rear door hinge portion 84 is formed in a band shape by the first tear line extension portion 72C and the second tear line extension portion 72D (composed of "planes" instead of "lines"), and Since the door hinge thin portion 84A is set to be thinner than the door base material general portion 68A, a flexible door hinge portion is configured. Therefore, the rear door hinge portion 84 is easily separated from the door base material main body portion 58 to deploy the door base material rear portion 68 to the passenger seat side. further,
In the present embodiment, the narrow door hinge thick portion 84 is provided along the second tear line extension 72D in addition to the thin door hinge portion 84A, so the hinge width of the rear door hinge portion 84 (the door hinge in the door width direction) Even if the width of the portion is narrowed, the rigidity of both side portions of the rear door hinge portion 84 is secured. Therefore, the door base material 44 is the first tear line extension 7
When split along 2C, the split can be reliably transferred to the second tear line extension 72D (that is, the split does not migrate to the second tear line extension 72D,
It is possible to stop the progress of the first tear line extension 72C in the extension direction. Therefore,
It is possible to reliably prevent the rear door hinge portion 84 from breaking and the airbag door 14 from scattering when the door is deployed.

As described above, according to the present embodiment, the air bubble door 14 is not scattered during the door deployment, and the door foam layer 46 is compressed during the door deployment (located above the rear door hinge portion 84). Interference can be mitigated, and eventually spring back (ie,
It is possible to minimize that the inflated bag 30 is pushed up from the position shown by the solid line in FIG. 5 to the position shown by the chain double-dashed line by the elastic restoring force of the door rear portion 50. As a result, according to the present embodiment, the deployment performance of the bag 30 can be stabilized (the bag 30 can be deployed in an optimum form) without scattering the airbag door 14.

Further, according to the present embodiment, as shown in FIG. 1, the door hinge thin portion 84A is formed by the door base general portion 6
The door foam layer 4 located above the door hinge thin portion 84A because it is offset to the door upper side from 8A.
The thickness t1 of 6 is smaller than the thickness t2 of the foamed door layer 46 located on the upper side of the door base general portion 68A. Further, since the thin door hinge portion 84A is offset to the upper side of the door than the door base general portion 68A, the airbag door 1
The substantial hinge length when 4 is expanded is longer. That is, when the thin door hinge portion 84A changes from the two-dot chain line shown in FIG. 2 to the solid line shown state, the inclined portion 84A1 extends and the hinge length a of the thin door hinge portion 84A (FIG.
(See (B)). As a result, according to the present embodiment, the airbag door 14 can be deployed more smoothly.

[Second Embodiment] The second embodiment of the present invention will be described below with reference to FIGS. 8 and 9. In addition,
The same components as those in the first embodiment described above are designated by the same reference numerals and the description thereof will be omitted.

As shown in these figures, in this embodiment as well, on the back surface side of the door base material 44 of the airbag door 14, a rear side tear line 90 demarcating the rear part 68 of the door base material and a door base. This is common to the above-described first embodiment in that a base material side tear line 92 including a front side tear line 74 that defines the material front portion 70 is formed.

However, in this embodiment, the rear side tear line 90 is formed in a frame shape composed of the width direction front side tear line 90A, the pair of front and rear direction tear lines 90B, and the width direction rear side tear line 90C. This is different from the rear tear line 72 of the first embodiment described above. That is,
In the present embodiment, a recessed groove 94 (see FIG. 9) as a “weakened portion” is formed in the portion that was the rear door hinge portion 84 in the above-described first embodiment, and the width direction rear side tear It functions as a line 90C.

Further, in this embodiment, the rear portion 6 of the door base material is used.
A linear strap accommodating groove 96 is formed at a position on the front surface side of 8 and slightly ahead of the rear side tear line 90C in the width direction. At both ends of the strap accommodating groove 96 in the longitudinal direction, strap insertion holes (not shown) are formed so as to penetrate through the door base material 44 in the plate thickness direction, and the side wall portion 60A of the mounting leg portion 60 of the airbag door 14 is further formed. Another strap insertion hole 100 is formed in the. Then, a cord-shaped (or band-shaped) strap 102 is passed through the strap accommodating groove 96, and further pulled out from the strap insertion holes at both ends thereof to the back surface side of the door base rear portion 68, and then the mounting leg portion. It is pulled out from the strap insertion hole 100 on the 60 side to the outside of the apparatus and is fixedly connected.

The strap 102 connects the rear portion 68 of the door base material and the mounting leg portion 60. As described in the above-described first embodiment, the airbag door 14 is configured such that the hook 64 on the airbag case 20 side is engaged with the engagement hole 62 formed in the mounting leg portion 60. Since it is attached to the airbag case 20, as a result, the door hinge portion side of the door base rear portion 68 is supported by the airbag case 20. Further, the strap 102 is provided in the strap receiving groove 96.
The lid (not shown) is fitted after the insertion.

According to the above construction, when a collision occurs, the bag 30 is inflated and the bag inflation pressure acts on the back surface of the door base material 44 of the airbag door 14. When the bag inflation pressure exceeds a predetermined value, the door rear portion 50 of the airbag door 14 is
Is broken not only from the width direction front side tear line 90A and the pair of front and rear direction tear lines 90B, but also from the width direction rear side tear line 90C. However, since the rear portion 68 of the door base material and the leg portion 60 for attachment are connected by the strap 102, the strap 102 extends and the airbag door 14
The rear part 50 of the door easily breaks and expands as shown in FIG. 9 (B). Also, as described above, the rear portion 6 of the door base material
Since the strap 8 and the mounting leg portion 60 are connected by the strap 102, the rear portion 50 of the door does not scatter.

Not only the strap 102 can be made of any material and can be set to have any width and length. Therefore, due to the interference of the foam door layer 46 located above the door hinge portion when the door is deployed. The problem of springback can be easily avoided. As a result, according to this embodiment, the deployment performance of the bag 30 can be stabilized (the bag 30 can be deployed in an optimal form).

In the second embodiment described above, the ends of the strap 102 are independently tied together outside the attachment legs 60 (a knot is provided), but both ends are attached to the attachment legs 60. May be knotted on the outside of the strap, or by changing the way of passing the strap 102, the strap 10 can be attached on the inside of the attachment leg 60.
The straps 102 may be tied, and the strap 102 may be passed or tied as desired as long as a reliable connection is obtained.
Furthermore, the strap 102 may be directly tied to the airbag case 20.

Further, in the second embodiment, the concave groove 94 is formed as the weak portion, but it is not always necessary to form the concave groove 94, the strength can be intentionally lowered, and the weak groove functions. All configurations are applicable.

Further, in the first and second embodiments, the present invention is applied only to the rear door hinge portion 84 of the door base rear portion 68, but the front door hinge portion 82 of the door base front portion 70 is used. The present invention may also be applied to.

[Disclosure Example] A disclosure example will be described below with reference to FIGS. 10 to 12. It should be noted that this disclosed example is not intended to be an embodiment of the present invention, and is intended only for disclosure of technology.

In this disclosed example, as shown in FIG.
An instrument panel skin 110 made of a resin material such as PVC or TPU and having a plane shape of a frame and a cross section of a long U shape (skin line on the skin side) 11
2 is formed, and a feature is that a pair of triangular notches 116 are formed on both sides of the front side portion 112A of the skin side tear line 112 having such a long U cross-sectional shape. The portion where the notch 116 is formed is near the root of the front tear line 74 in the above-described first and second embodiments, that is, a connection portion to the rear tear lines 72 and 90 of the front tear line 74. There is.

FIG. 11 is an enlarged view of the notch 116, but the opening angle θ of the notch 116, the height h, the radius of curvature of the apex angle portion, etc. are set arbitrarily. Also, the notch 116
Is formed by devising a mold structure when manufacturing the instrument panel skin 110, but notches 1 are not always formed by the mold.
It is not necessary to form 16 and a cut may be made in advance with a knife or the like.

When the notch 116 is previously formed in the front side portion 114A of the skin side tear line 112 as described above, the door base material, and thus the door front part, is moved along the front side tear line of the door base material as shown in FIG. When the notch 116 is formed on the windshield glass side, the portion where the notch 116 is formed serves as a fracture starting point, which facilitates the front part of the door to be expanded and stabilizes the expanded state of the front part of the door.

[0060]

As described above, in the passenger-side airbag door structure according to the present invention as defined in claim 1, other than the pair of front-rear direction tear lines in the rear-side tear line that defines at least the rear portion of the door base material. A first tear line extension extending from the rear end of the front-rear direction tear line toward the inside of the door and a second tear line extension extending from the inner end of the first tear line extension toward the vehicle front side. Further, a thin portion of the door hinge that is thinner than the general portion of the door base material, and a pair of thin portions that are narrower along the second tear line extension and that are thicker than the thin portion of the door hinge. Since the door hinge part is configured to include the thick part of the door hinge, the interference of the foam layer (located above the door hinge part) at the time of deploying the door is mitigated, and the spring bag after deploying the door is relaxed. It can be suppressed to a minimum, with the result, without scattering the air bag door, an excellent effect that the development performance of the bag can be stabilized (to deploy in an optimal form the bag).

According to the second aspect of the present invention, the airbag door structure for a passenger seat according to the first aspect of the present invention is characterized in that the thin portion of the door hinge is offset to the upper side of the door from the general portion of the door base material. The thickness of the foam layer on the upper side of the thin portion of the door hinge becomes thin, and the substantial hinge length of the door hinge portion becomes longer. As a result, the airbag door can be deployed more smoothly. .

In the passenger-side airbag door structure according to the third aspect of the present invention, at least the door hinge portion, which is the deployment center of the rear portion of the door base material, separates the rear portion of the door base material from the main body of the door base material. While forming a fragile portion for breaking of, since the door hinge portion side in the rear portion of the door base material and the air bag case for accommodating the bag or the leg portion for attaching the air bag door to the air bag case are connected by straps, By arbitrarily setting the strap material, width, length, etc., you can easily avoid the problem of springback when deploying the door, and as a result, you can improve the deployment performance of the bag without scattering the airbag door. It has an excellent effect that it can be stabilized (the bag can be developed in an optimum form).

[Brief description of drawings]

FIG. 1 is an enlarged vertical sectional view taken along the line 1-1 of FIG. 7 showing an airbag door structure for a passenger seat according to a first embodiment.

FIG. 2 is an enlarged cross-sectional view of a two-line arrow section (rear door hinge section) shown in FIG.

FIG. 3A is an enlarged cross-sectional view in which only a door base material portion of a rear door hinge portion is extracted, and FIG. 3B is a range in which a thin portion of the door hinge and a thick portion of the door hinge forming the rear door hinge portion are formed. FIG. 5 is a back view for explaining dimensions and the like.

FIG. 4 is a schematic plan view showing a formation range of a rear door hinge portion in relation to a base material side tear line.

FIG. 5 is a schematic side view for explaining an effect (suppression of springback) brought about by the passenger airbag device according to the first embodiment.

FIG. 6 is a schematic plan view showing a skin side tear line and a base material side tear line of a passenger side airbag door of an instrument panel.

FIG. 7 is an external perspective view of an instrument panel.

FIG. 8 is an overall perspective view showing a door base material according to a second embodiment.

9 (A) and 9 (B) are enlarged vertical cross-sectional views taken along line 9-9 of FIG. 8 showing states before and after the rear portion of the door is broken.

FIG. 10 is a schematic perspective view of a main part of an instrument panel showing a disclosed example in which a skin-side tear line is improved.

11 is an enlarged view of the notch shown in FIG.

FIG. 12 is a schematic perspective view of relevant parts showing a state in which the epidermis of the instrument panel shown in FIG. 10 is cleaved and expanded.

FIG. 13 is a vertical cross-sectional view of a passenger seat airbag device according to a conventional example.

[Explanation of symbols]

10 Instrument panel 12 Passenger airbag device 14 airbag door 20 airbag case 30 bags 42 door skin 44 Door base material 46 Door foam layer 52 Epidermis side tear line 56 windshield glass 58 Door base material 60 mounting legs 66 Base material side tear line 68 Rear of door material 68A Door base material general part 72 Rear tear line 72B Front-rear direction tear line 72C 1st Tier Line Extension 72D Second Tier Line Extension 84 Rear door hinge part 84A Door hinge thin-walled part 84B Door hinge thick part 90 Rear tear line 92 Base material side tear line 94 Groove (fragile part) 102 strap

─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Yoko Negi 1 Toyota Town, Toyota City, Aichi Prefecture Toyota Motor Corporation (56) References JP-A-10-71906 (JP, A) JP-A-11-301398 (JP, A) JP 11-278191 (JP, A) JP 10-236263 (JP, A) JP 2000-264159 (JP, A) JP 10-236260 (JP, A) JP JP-A-9-136594 (JP, A) JP-A-11-42998 (JP, A) JP-A-2000-71915 (JP, A) JP-A-6-321041 (JP, A) JP-A-8-169291 (JP, A) JP 10-1015 (JP, A) JP 7-179161 (JP, A) JP 9-52567 (JP, A) JP 7-156737 (JP, A) US Pat. US, A) US Patent 5564731 (US, A) (58) Fields investigated (Int.Cl. ⁷ , DB name) B60R 21/16-21/32 B60K 37/00

Claims (3)

(57) [Claims] 1. A base material-side tear line that is cleaved when subjected to a bag inflation pressure of a predetermined value or more, and after the cleaving along the base material-side tear line, both the windshield glass side and the passenger seat side. And a door base made of a resin that is expanded to a front side of the door base, which is spaced apart from the front side of the door base, is formed corresponding to the base side tear line, and is cleaved by the bag inflation pressure. The airbag door structure for a passenger seat includes a resin door skin having a side tear line, and a foam layer interposed between the door skin and the door base material to integrate the two with each other. In the door base material, at least a rear side tear line that defines a rear part of the door base material that is a portion that expands to the passenger seat side is a pair of front and rear direction tear lines that are formed substantially in parallel, and the pair of front and rear directions. The from both the rear end of Iarain pair only extended respectively predetermined size to the door inner side 1
And a pair of second tear line extensions that extend from the inner ends of the pair of first tear line extensions to the front side of the vehicle by a predetermined dimension. The door hinge portion sandwiched between the pair of second tear line extension portions is provided with a thin door hinge portion formed thinner than the door base general portion, and a narrow width along the second tear line extension portion. An air bag door structure for a passenger seat, comprising: a pair of thick-walled door hinge portions formed thicker than a thin-walled door hinge portion. 2. The passenger-side airbag door structure according to claim 1, wherein the thin-walled door hinge portion is offset toward a door upper side than the door base general portion. 3. A base material side tear line which is cleaved when subjected to a bag inflation pressure of a predetermined value or more, and both the windshield glass side and the passenger seat side after the cleavage along the base material side tear line. A resin door base material that expands to and a door side base material that is spaced apart from the front surface side of the door base material and is formed corresponding to the base material side tear line and is cleaved when the bag inflation pressure acts. A passenger door airbag door structure including: a resin door skin having a line; and a foam layer interposed between the door skin and a door base material to integrate the two, At the door hinge part, which is the center of expansion of the rear part of the door base material, which is a part of the door base material that expands to the passenger side, a fragile portion for breaking for separating the rear part of the door base material from the main body of the door base material. Shape Further, the door hinge portion side at the rear portion of the door base material and an air bag case for accommodating the bag or a leg portion for attaching the air bag door to the air bag case are connected by a strap. Air bag door structure for the passenger seat.