JPH0732964A - Airbag device - Google Patents

Abstract

(57) [Summary] [Object] The present invention can reduce the weight and cost of the entire apparatus by eliminating the reinforcement of the portion other than the easily breakable portion, and the airbag can be folded regardless of the folding method of the airbag. (EN) An airbag device that can be deployed at an early stage. [Structure] In an airbag device 25 according to the present invention, a cover body 31 has an easily breakable portion 33 that is broken by the deployment force of the airbag.
And a lid portion 35 that is opened so as to form an opening for deploying the airbag by rupture.
5 is formed by an upper split lid part 37 and a lower split lid part 39 which are divided into upper and lower split break parts 45, lateral break parts 47 and 49, and the lower split lid part 39 is a lower central break part 51. It is characterized in that it is divided into two by the lower division breaking portion 53 and divided into the lower subdivision lid portions 41 and 43.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an airbag device which is attached to an in-vehicle accessory and protects an occupant in a vehicle collision.

[0002]

2. Description of the Related Art FIGS. 10 and 11 show Japanese Patent Laid-Open No. 63-21.
2 shows an airbag device 1 described in Japanese Patent No. 2147. The airbag device 1 includes a steering shaft 3 (see FIG. 11).
(See) a steering wheel as an in-vehicle accessory attached to the upper end of the steering wheel.

The airbag device 1 is provided with an airbag unit 9 that accommodates an airbag 7 that is deployed in the passenger compartment, and a cover body 11 that covers the front surface of the airbag unit 9. Further, the cover body 11 is divided by an H-shaped easily breakable portion 13 (see FIG. 10) that is broken by the deploying force of the airbag 7, and a lid portion that is opened so as to form an opening for airbag deployment by the breakage. 15 are provided. The lid portion 15 is composed of an upper divided lid portion 17 and a lower divided lid portion 19 which are divided into upper and lower portions.

When the lid portion 15 is opened so as to form an opening for deploying the airbag, a strong deploying force of the airbag 7 is given to the cover body 11, so that the hinge portion 21, The parts other than the easily breakable parts 13 are thickened and reinforced so that the parts 23 are not broken and scattered, and the rigidity is maintained.

When the vehicle collides with the inflator 9a.
When the air bag 7 is ignited and the airbag 7 is deployed by the gas pressure, the easy breaking portion 13 is broken by the deploying force, the upper split lid portion 17 is bent upward from the hinge portion 21, and the lower split lid portion 19 is bent by the hinge portion 21. Bends downward from the lid 15
Open to form an opening for airbag deployment. As shown in FIG. 12, the airbag 7 is deployed to the occupant side through this opening so that the occupant is received and reliably protected.

[0006]

However, in the above-mentioned airbag device 1, since the portions other than the easily breakable portion 13 are made thick for reinforcement, the weight of the entire airbag device is high and the cost is high. Was there. In particular, when the lid portion 15 is divided into two as in the conventional case, each divided lid portion 17 and 1
9 becomes heavier, and the inertial force of the lid portions 17 and 19 received by the hinge portions 21 and 23 becomes larger. For this reason, the reinforcement of the hinge portions 21 and 23 must be increased accordingly, which is an obstacle to weight reduction and cost reduction.

In the airbag device 1, depending on the folding method of the folded airbag 7, the deploying airbag 7 becomes difficult to open, and it takes time for the airbag 7 to stabilize after opening. There is a risk of causing problems such as the need to use a large inflator for improvement.

That is, in order to improve the visibility of the meters and the like, when the upper split lid portion 17 is curvedly formed as shown in FIG. 11, the airbag 7 is on the lower side (the lower split lid portion 19).
It may have a structure in which it is folded a lot. In the case of such a structure, if the weight of the lower split lid portion 19 is large, it impedes the deployment of the airbag 7 and
It will take time until the open state of the lower split lid portion 19 stabilizes. On the other hand, the airbag 7 needs to be deployed earlier than the side of the lower split lid portion 19 that is folded a lot. For this reason, a large inflator 9a is required, which may lead to an increase in size, weight, and cost of the device.

[0009] Therefore, an object of the present invention is to provide an airbag device which can reduce the size, weight and cost of the device.

[0010]

In order to achieve the above object, according to the present invention, an airbag unit which is attached to an in-vehicle accessory and accommodates an airbag which is deployed into a vehicle compartment, and a cover body which covers a front surface of the airbag unit. The cover body is provided with a lid portion that is divided by an easily breakable portion that is broken by the deployment force of the airbag and that is opened so as to form an opening for deploying the airbag by the fracture, and the lid portion is divided into upper and lower portions. It is characterized in that the upper divided lid portion and the lower divided lid portion are formed, and at least the lower divided lid portion is formed by a plurality of lower fine divided lid portions.

[0011]

In the airbag apparatus of the present invention, when the airbag is deployed at the time of a vehicle collision, this deploying force causes the easily breakable portion to break, and the upper split lid portion and the lower split lid portion open the airbag for opening. Open to form. Also,
A plurality of lower subdivided lid portions are opened in the lower divided lid portion so as to form an opening for airbag deployment.

In this case, since at least the lower split lid portion is divided into a plurality of lower subdivided lid portions having a small weight, when the lower split lid portion is opened by the deploying force when the airbag is deployed, other than the easy breakable portion. The inertial force of the lower subdivided lid portion received by the portion is reduced. Therefore, the reinforcement of the portion other than the easily breakable portion can be reduced, and the weight and cost of the device can be reduced.

Further, since at least the lower split lid portion is divided into a plurality of lower subdivided lid portions having a smaller weight, the time required for the lower split lid portion to open and become stable becomes shorter, and after the airbag is opened. The time to stabilize can be shortened. As a result, for example, even when the airbag is folded in multiple layers on the lower split lid portion side, the airbag can be easily opened and can be deployed early. Further, since the air bag is easily opened, for example, the inflator can be downsized, and the size and weight of the device can be reduced and the cost can be reduced.

[0014]

Embodiments of the airbag device according to the present invention will be described below. 1 is a front view showing the center pad portion of the steering wheel, and FIG. 2 is I of FIG.
Sectional drawing cut | disconnected along the I-II line, FIG. 3 is the perspective view which looked at a part of center pad from the back surface side, and FIG. 4 is the expanded sectional view of a part of FIG. FIG. 5 is a front view showing a state in which the lid is opened.

As shown in FIG. 2, the airbag device 25 of this embodiment is attached to the center pad portion of the steering wheel. The airbag device 25 includes an airbag unit 29 that accommodates an airbag 27 that is deployed in the vehicle compartment, and a cover body 31 that covers the front surface of the airbag unit 29.

The airbag unit 29 includes a base plate 30 having a U-shaped cross section and the base plate 30.
The inflator 34 fixed to the inflator 3 and the inflator 3
4 and an inflator cover 36 covering one surface side of the base plate 4, and the airbag 27 is attached to the one surface side of the base plate 30 by a retainer 32. A cover body 31 is arranged on the front side of the airbag 27. Supporting portions 31a, 31a are provided so as to project from the back surface side of the cover body 31. These support portions 31a, 31a are fixed to the outer peripheral portion of the base plate 30 via stop members 38, 38. As a result, the front surface side of the airbag unit 29 is covered with the cover body 31, and the airbag 27 is accommodated between the cover body 31 and the base plate 30.

The cover body 31 is integrally formed of synthetic resin, and the core material 42 is inserted in the middle portion in the thickness direction. As shown in FIG. 1, the cover body 31 is divided by an easily breakable portion 33 that is broken by the deploying force of the airbag 27,
A lid portion 35 that is opened so as to form an opening for deploying the airbag 27 by breaking is provided. Lid part 3
5 is formed by an upper divided lid portion 37 and a lower divided lid portion 39 which are divided into upper and lower portions, and a lower divided lid portion 39.
Is divided into two sub-divided lower sub-lid portions 41 and 43.

The easily breakable portion 33 is divided into upper and lower breakable portions 4.
5, lateral break portions 47 and 49, lower central break portion 51, and lower split break portion 53. The upper and lower split breaking portions 45 are formed in the center portion of the cover body 31 along the left-right direction. Lateral breaks 47 and 49, which are formed along the vertical direction and whose upper ends bend in directions toward each other, are connected to both ends of the upper and lower split breaks 45, respectively. Also,
A wavy lower central rupture portion 51 extends downward from an intermediate portion of the upper and lower split rupture portions 45, and a lower end of the lower central rupture portion 51 is provided substantially parallel to the upper and lower split rupture portions 45. It is connected to the intermediate portion of the lower split breakage portion 53.

The upper split lid portion 3 and the upper split lid portion 3 are formed by the upper and lower split fracture portions 45 and the lateral fracture portions 47 and 49.
7 and the lower split lid part 39, and the lower split lid part 39 is divided by the lower center broken part 51 and the lower split broken part 53.
Is divided into lower subdivided lid portions 41 and 43.

As shown in FIG. 3, the easily breakable portion 33 for partitioning the lid portion 35 is provided with a groove 48 having a triangular cross section on the back surface side of the cover body 31 to locally cover the cover body 31. It is formed by making it thin. In addition to the groove 48, the top-bottom split breakage portion 45 is provided with a recess 73 on the front surface side of the cover body 31, and the thickness of the recess 73 and the groove 48, that is, the thickness of the top-bottom split breakage portion 45 is different. Is formed thinner than the thickness of the fractured portions 47, 49, 51, 53. Further, at the end of the groove 48, the fractured portions 47, 49, 5
Circular recesses 55, 5 for stopping the progress of the fracture of 3
7, 59, 61, 65 and 67 are formed. As shown in FIG. 1, the recesses 55 and 57 formed at one end of the lateral breaks 47 and 49 have a diameter slightly larger than the width dimension of the groove 48, and the recesses formed at the other end. 59, 6
1 is formed to have substantially the same diameter as the width dimension of the groove 48. Also,
Recesses 65 and 67 formed at both ends of the lower split break 53
Is also formed to have substantially the same diameter as the width dimension of the groove 48.

The space between the recesses 55 and 57 is the hinge 63 of the upper split lid part 37, and the space between the recesses 59 and 65 is the hinge 69 of the lower fine split lid part 41, and the recesses 61 and 6 are formed.
A portion between 7 is a hinge portion 71 of the lower subdivided lid portion 43.

Further, as shown in FIG. 4, the thickness L1 of the core member 42a on the side of the upper divided lid portion 37 is determined by the lower divided lid portion 39.
The thickness is set to be thicker than the thickness L2 of the core material 42b on the side, and the core material 42a on the upper split lid portion 37 side and the lower split lid portion 39.
The connecting portion with the core material 42 b on the side, that is, the portion where the thickness dimension changes is located between the recess 74 and the groove 48. As a result, when the upper and lower split breaking portions 45 are broken by the deploying force of the airbag, stress concentrates on the portion where the thickness dimension changes, so that the core material 42 is easily broken. The upper and lower split break portions 45 are formed by forming the recesses 74 on the front surface side and the grooves 48 on the back surface side, so that the other break portions 47, 49, 5 are formed.
It is configured to be more easily broken than the Nos. 1 and 53. When the airbag is deployed, the upper and lower split rupture portions 45 are ruptured prior to the other rupture portions to form the airbag deployment opening.

Further, in this embodiment, the upper divided lid portion 37 is not divided into a plurality of lid portions. The reason for this is
The inertial force of the upper split lid portion 37 at the time of deploying the airbag 27 is not as great as that of the lower split lid portion 39 that also receives gravitational acceleration at the time of deploying the airbag, and the airbag is multi-layered on the lower split lid portion 39 side. This is to facilitate opening of the airbag when folded.

Next, the operation of this embodiment will be described.

The inflator 34 is detected by a vehicle collision detection or the like.
When the ignition is ignited, the folded air bag 27 is inflated by the gas pressure, and the air bag 27 breaks the surface of the cover body 31 and inflates to start the deployment. When the airbag 27 is inflated, the deploying force of the airbag 27 is applied to the cover body 31, the cover body 31 is fractured from the upper and lower split fracture portions 45 and the lateral fracture portions 47, 49, and the lower central fracture portion 51. The fracture also occurs from the lower split fracture part 53. Upper and lower split breaks 45, lateral breaks 47, 49, lower central break 51,
When the lower split breaking portion 53 is broken, as shown in FIG. 5, the upper split lid portion 37 is bent upward at the hinge portion 63, and the lower fine split lid portions 41 and 43 are slanted downward at the hinge portions 69 and 71. It bends to form an opening 40 for deploying the airbag. The airbag 27 is deployed into the vehicle compartment through this opening 40.

According to the present embodiment, by dividing the lower split lid portion 39 into the lower subdivided lid portions 41 and 43 having a smaller weight by the lower central fracture portion 51 and the lower split fracture portion 53,
Lower subdivided lid portions 41, 4 received by the hinge portions 69, 71.
The inertial force of 3 becomes small. As a result, the hinge portion 69,
Since the reinforcement of 71 etc. can be reduced, the cover body 3
It is possible to reduce the weight by 1, and it is possible to reduce the cost.

Further, according to this embodiment, since the lower split lid portion 39 is divided into the lower subdivided lid portions 41 and 43 having a smaller weight, the lower subdivided lid portion does not interfere with the airbag deployment. Since it takes a short time until the open state of the parts 41 and 43 becomes stable, the airbag can be easily opened, and the airbag can be deployed early. As a result, the inflator for deploying the airbag can be downsized, so that the device can be downsized and the weight and cost can be reduced.

Further, according to this embodiment, the airbag 2
Even when 7 is folded to the side of the lower split lid portion 39, the lower split lid portion 39 may be replaced by the lower fine split lid portions 41, 4 and 4.
By dividing into three, the lower subdivided lid portions 41, 4
Since the respective weights of 3 are reduced, the airbag can be easily opened, and the airbag can be deployed at an early stage. Therefore, the passenger protection performance can be further improved.

Further, by forming the lower central rupture portion 51 into a corrugated shape, it becomes easier to rupture due to the deploying force of the airbag 27, and the airbag 27 on the lower split lid portion 39 side can be deployed earlier. Yes, the occupant protection performance can be further improved.

Next, referring to FIGS. 6 to 9, the cover body 31
An example of another mode of the easily breakable portion provided in will be described. In each figure, the part indicated by the dotted line is the fractured part, and the part indicated by the chain double-dashed line is the hinge part.

The easily breakable portion provided on the cover body 75 shown in FIG. 6 is such that, in the above embodiment, the lower central breakable portion 51 is formed into a straight line from the corrugation, and the upper split lid portion 37 is replaced by the upper fine split lid portions 37a, 37b. This is an example in which an upper central break portion 77 that is divided into

In the present embodiment, the deploying force of the airbag 27 causes the upper and lower split breaks 45, the lateral breaks 47 and 49, the lower central break 51, and the upper central break 77 to break, thereby expanding the airbag. Forming an opening for.

According to the present embodiment, the lower central split portion 51 and the lower split fracture portion 53 divide the lower split lid portion 39 into lower fine split lid portions 39a and 39b having a small weight, and the upper split lid portion 37. Is divided into upper subdivided lid portions 37a, 37b having a smaller weight by the upper central break portion 77, so that the lower subdivided lid portions 39a, 39b and the upper subdivided lid portions 37a, 37b received by the hinge portions 69, 71, 63.
The inertial force of becomes smaller. Thereby, the hinge portions 69, 7
Since the reinforcement of Nos. 1 and 63 can be reduced, the weight can be further reduced and the cost can be reduced as compared with the above embodiment.

Further, according to the present embodiment, the lower divided lid portion 39 and the upper divided lid portion 37 are made up of the lower subdivided lid portions 39a and 39b and the upper subdivided lid portions 37a and 37b, which have a smaller weight.
By dividing the lower subdivision lid portions 39a, 3a, 3
9b, the time required for the upper subdivided lid portions 37a, 37b to bend and stabilize in the open state is shortened, and the time required for the airbag to stabilize after being opened is shortened. This makes it easier to open the airbag, so that the airbag can be deployed early. Therefore, since the airbag is easier to deploy than in the above-described embodiment, the inflator can be downsized, and the device can be further downsized in comparison with the above-described embodiment.
The weight and cost can be reduced.

Further, in this embodiment, whether the airbag is folded in multiple layers on the side of the lower split lid portion 39 or multiple layers on the side of the upper split lid portion 37, the lower fine split lid of small weight is used. Since the upper split lid portion 37 and the lower split lid portion 39 are divided into the portions 39a and 39b and the upper subdivided lid portions 37a and 37b, the airbag becomes easier to open, and the airbag is deployed earlier than the above-described embodiment. It is possible to improve the passenger protection performance.

In the easily breakable portion of the cover body 79 shown in FIG. 7, the lower split lid portion 39 is formed into a substantially triangular lower fine split lid portion 39.
inclined break parts 81, 83 divided into a, 39b, 39c
Is an example in which is provided.

In the present embodiment, the expanding force of the airbag 27 causes the upper and lower split breaks 45, the lateral breaks 47 and 49, and the inclined breaks 81 and 83 to break to form an opening for expanding the airbag. .

According to this embodiment, the inclined fractured portions 81, 83
Since the lower split lid portion 39 is divided by the lower fine split lid portions 39a, 39b, 39c by
The inertial force received by the hinge portions 69, 71, 85 is reduced. As a result, the reinforcement of the hinge portions 69, 71, 85 can be reduced, so that the weight can be reduced and the cost can be reduced.

Further, according to this embodiment, the lower split lid portion 39 is divided into three lower subdivided lid portions 39a, 3a having a smaller weight.
By dividing into 9b and 39c, the inertial force becomes smaller than that of the lower split lid portion of the embodiment shown in FIG. 6, and the time until the lower fine split lid portions 39a, 39b, 39c bend and become stable in the open state is shorter. As a result, the time from the opening of the airbag until it stabilizes becomes shorter, and the airbag can be deployed early. As a result, the inflator for deploying the airbag can be downsized, the device can be downsized, and the weight and cost can be reduced.

Further, in this embodiment, the lower split lid portion 39
The airbag folded in multiple layers on the side can be deployed early and the occupant protection performance can be improved.

The easily breakable portion of the cover body 87 shown in FIG. 8 is formed on the easily breakable portion of the cover body 79 shown in FIG.
This is an example in which an upper central fractured portion 77 is provided to divide the upper subdivided lid portions 37a and 37b.

According to this embodiment, the upper split lid portion 37,
The lower divided lid portion 39 is replaced by the upper fine divided lid portion 3 having a small weight.
7a, 37b, 37c, lower subdivided lid portions 39a, 39
Since it is divided into b and 39c, the hinge portions 69, 71 and 8
Lower subdivided lid portions 39a, 39b, 3 received by 5, 63
9c, the inertial force of the upper subdivided lid portions 37a, 37b is shown in FIG.
It is smaller than the embodiment shown in. As a result, the hinge portion 6
Since the reinforcement of 9, 71, 85, 63 can be reduced, the weight can be reduced and the cost can be reduced as compared with the embodiment shown in FIG.

Further, according to this embodiment, since the upper subdivided lid portions 37a, 37b, 37c and the lower subdivided lid portions 39a, 39b, 39c having a smaller weight are divided, the upper subdivided lid portions 37a, 37b, 37c, lower subdivision lid part 3
The time from the opening of 9a, 39b, 39c to the stabilization is shortened, and the airbag can be deployed early. As a result, it is not necessary to use a large inflator to deploy the airbag at an early stage, and it is possible to further reduce the size of the device and reduce its weight and cost as compared with the embodiment shown in FIG.

Further, in this embodiment, similarly to the embodiment shown in FIG. 7 described above, the airbag folded in multiple layers on the side of the lower split lid portion 39 can be deployed at an early stage.
Since the upper split lid portion 37 is divided into the upper fine split lid portions 37a and 37b by the upper central breaking portion 77, the airbag folded in multiple layers on the upper split lid portion 37 side can be deployed at an early stage. Therefore, the airbag can be deployed early regardless of how the airbag is folded.

The easily breakable portion of the cover body 89 shown in FIG. 9 corresponds to the hinge portion 6 at the easily breakable portion of the cover body 75 shown in FIG.
This is an example in which the positions of 9, 71 are changed. That is, since the hinge portions 69 and 71 are located below the lid portion 35,
The upper subdivided lid portions 37a and 37b open upward, and the upper central fracture portion 77 fractures. Further, the lower subdivided lid portions 39a and 39b open downward, and the lower central fracture portion 51 fractures.

Also in this embodiment, the same effect as that of the embodiment shown in FIG. 6 can be obtained, and the downsizing of the device, the weight and the cost reduction can be achieved. In addition, the airbag can be deployed at an early stage and the occupant protection performance can be improved.

[0047]

As described above, in the airbag device according to the present invention, at least the lower divided lid portion is formed by the plurality of divided lower fine divided lid portions, so that it is applied to the portion other than the easily breakable portion. The inertial force of the lower subdivided lid part can be reduced. Therefore, since the reinforcement of the portion other than the easily breakable portion can be reduced, the weight can be reduced and the weight and the cost can be reduced.

Further, since at least the lower split lid portion is formed of a plurality of lower subdivided lid portions having a small weight, the inertial force of the lower subdivided lid portion applied to a portion other than the easily breakable portion is small, and the lower subdivided lid portion is small. It is possible to shorten the time from when the lid part opens until it stabilizes. Therefore, the time from the opening of the airbag until it becomes stable is shortened, so that the airbag can be easily opened and the airbag can be deployed at an early stage.

[Brief description of drawings]

FIG. 1 is a front view showing a center pad portion provided with an airbag device according to the present invention.

FIG. 2 shows an airbag device according to the present invention, which is indicated by I in FIG.
It is sectional drawing cut | disconnected along the I-II line.

FIG. 3 is a perspective view showing a structure of an easily breakable portion.

FIG. 4 shows a top and bottom split breakage portion provided in the cover body, and FIG.
It is the sectional view to which a part of was enlarged.

FIG. 5 is a front view showing a state in which the airbag device according to the present invention is activated.

FIG. 6 is a front view showing another aspect of the breakage portion provided in the cover body.

FIG. 7 is a front view showing another aspect of the breakage portion provided in the cover body.

FIG. 8 is a front view showing another aspect of the breakage portion provided in the cover body.

FIG. 9 is a front view showing another aspect of the breakage portion provided in the cover body.

FIG. 10 is a front view showing a conventional airbag device.

FIG. 11 is a cross-sectional view showing a conventional airbag device.

FIG. 12 is a side view showing a state in which the conventional airbag device is activated and the airbag is deployed.

[Explanation of symbols]

 25 Airbag device 27 Airbag 29 Airbag unit 31 Cover body 33 Easy breakable portion 35 Lid portion 37 Upper split lid portion 39 Lower split lid portion 41 Lower subdivided lid portion 43 Lower subdivided lid portion

Claims (1)

[Claims] 1. An airbag unit that is attached to an in-vehicle accessory and accommodates an airbag that is deployed into a vehicle compartment; and a cover body that covers a front surface of the airbag unit, the cover body including the airbag. Is provided with a lid portion that is divided by an easy-breaking portion that is broken by the deploying force of the lid and that is opened to form an opening for airbag deployment by the breaking, the lid portion being divided into upper and lower portions by the easy-breaking portion. An airbag device, comprising: a lid portion and a lower divided lid portion, and at least the lower divided lid portion is formed by a lower subdivided lid portion divided into a plurality of easily breakable portions.