JP4668459B2 - Automotive airbag equipment - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an airbag apparatus for an automobile, and more particularly to an airbag apparatus for a passenger seat.
[0002]
[Prior art]
Inside the instrument panel located below the front window panel, an airbag module containing an airbag and an inflator is installed. The lower part of the airbag module is fixed to a steering member arranged along the vehicle width direction inside the instrument panel, and the upper part is locked to a pair of front and rear mounting pieces integrally formed on the back surface of the instrument panel. Yes.
[0003]
An opening / closing door portion defined in the instrument panel itself is provided between the pair of mounting pieces at a portion corresponding to the airbag of the instrument panel by a closed loop-shaped cleavage groove formed on the back surface. (For a similar technique, refer to JP 2001-39254 A).
[0004]
Thus, the reason why the opening / closing door portion is formed in the instrument panel itself is that it looks better than the case where an opening is formed in the instrument panel and a separate opening / closing lid is provided there. . On the back side of the opening / closing door portion, an aluminum backing member is formed extending beyond the cleavage groove to the outside of the opening / closing door portion. When the airbag is inflated, the entire opening / closing door portion is pushed through the backing member by the inflation force of the airbag, and the opening / closing door portion is broken and separated from the tear groove. The separated opening / closing door part can be opened to the outside by using the part corresponding to the cleavage groove of the backing member as a hinge part, and the airbag can be deployed to the inside of the vehicle from the opening after the opening / closing door part is removed. it can.
[0005]
[Problems to be solved by the invention]
However, in such a conventional technique, the backing member connected to the back side of the opening / closing door portion of the instrument panel is made of metal (aluminum). The covered portion is not directly subjected to the inflation force of the airbag. That is, since the backing member is made of metal and does not deform flexibly, the inflating force of the airbag cannot be directly applied to the cleavage groove of the portion covered by the backing member, and the opening / closing door portion is not connected via the backing member. By the indirect action of pushing the entire surface, the cleavage groove at that part is broken. Therefore, in order to reliably break such a cleavage groove, it is necessary to make the inflator for inflating the airbag large in size and high output, which is disadvantageous in terms of weight and cost.
[0006]
The present invention has been made by paying attention to such a conventional technique, and is an automobile that can reliably break the cleavage groove covered with the backing member without making the inflator large and high-powered. An airbag device is provided.
[0007]
[Means for Solving the Problems]
Invention of claim 1, wherein, with installing the airbag module housing the airbag and the inflator on the back of the instrument panel made of resin, the instrument closed loop cleavage on the back of the panel corresponding to the air bag forming a groove defines a door portion, the back side of the door portion, the larger backing member than the door unit, with binding to the inside and outside of the door portion, the Urato the outer section than the door portion of the member, a pair of mounting pieces before and after locking the top of the air bag module, formed at an angle relative to the backing member, said the backing member, the cleavage groove before providing a hinge portion corresponding to either side or the rear side at least, and the other to provide a cutting portion, centered on the said hinge portion, the expansion force of the airbag, the instrument Pas An airbag apparatus for an automobile which enables opening of the door portion, separated from the Le, the hinge portion of the backing member, the cleavage is deformed by the expansion force of the airbag covering the rupturing groove characterized in that it is made of soft resin for strength Oyoboseru the expansion force in the groove.
[0008]
According to the first aspect of the present invention, since the backing member is made of a soft resin having a strength that can be deformed by the inflating force of the airbag and exert the inflating force on the cleavage groove, the hinge portion itself is covered even with the hinge portion. Is flexible, the cleavage groove is easy to break, and the inflator does not need to be large and have high output. Therefore, it is advantageous in terms of weight and cost.
[0009]
In the invention according to claim 2, the backing member has a flexural modulus of 6000 kgf / cm ² or less (preferably 4500 kgf / cm ² or less).
[0010]
According to the invention described in claim 2, since the backing member has a flexural modulus of 6000 kgf / cm ² or less (preferably 4500 kgf / cm ² or less), it can be flexibly deformed by the expansion force of a normal airbag. it can.
[0011]
According to the third aspect of the present invention, the attachment piece is in a position close to the cleavage groove.
[0012]
According to the third aspect of the present invention, since the mounting piece is in a position close to the cleavage groove, the expansion force of the airbag is concentrated on the cleavage groove by suppressing the movement of the proximity position of the cleavage groove by the mounting piece. Easy separation of the opening / closing door part from the instrument panel.
[0013]
In the invention according to claim 4, the pair of front and rear mounting pieces are formed as front and rear facing surface portions of a cylindrical body formed outside the cleavage groove of the backing member.
[0014]
According to the invention of claim 4, since the pair of front and rear mounting pieces are formed as the front and rear facing surface portions of the cylindrical body, even if the backing member is made of a soft resin, the strength of the mounting piece is increased, and the airbag module The support strength is improved and the function of guiding the inflation direction of the airbag by the cylindrical body is also improved.
[0015]
The invention according to claim 5 is a cutting groove in which the cleavage groove is processed after molding the instrument panel.
[0016]
According to the fifth aspect of the present invention, since the cleavage groove is a cutting groove, molding sinks and gloss unevenness do not occur on the surface of the instrument panel.
[0017]
In the invention according to claim 6, the connection between the instrument panel and the backing member is a connection by ultrasonic horn welding.
[0018]
According to the invention described in claim 6, since the backing member is bonded to the instrument panel by ultrasonic horn welding, it is advantageous for multi-point bonding, and gloss unevenness does not occur on the surface of the instrument panel. .
[0019]
In the invention according to claim 7, the hinge portion of the backing member has a curved shape straddling the cleavage groove.
[0020]
According to the invention of claim 7, since the hinge portion of the backing member has a curved shape straddling the cleavage groove, the hinge portion is prevented from being sharpened when the opening and closing door portion is opened, and the airbag is in a curved state. Will abut. Even if the hinge portion is curved, the airbag can be deformed at the initial stage of inflation and exert an inflating force on the cleavage groove.
[0021]
DETAILED DESCRIPTION OF THE INVENTION
Preferred embodiments of the present invention will be described below with reference to the drawings.
[0022]
1 to 6 are views showing a first embodiment of the present invention. Reference numeral 1 denotes an automobile instrument panel, and a front window panel 2 is positioned above the instrument panel. The instrument panel 1 is a molded product made of a hard polypropylene resin having a flexural modulus of 30300 kgf / cm ² , and the surface thereof is subjected to matte texture to prevent reflection on the front window panel 2. The instrument panel 1 is preferably a hard resin having a flexural modulus of 11000 kgf / cm ² or more (preferably 19000 kgf / cm ² or more).
[0023]
An airbag module 3 is installed inside the instrument panel 1. The airbag module 3 includes a reaction can 5 having a built-in inflator 4 fixed to a steering member 7 with a bracket 6, a case 8 fixed to a gas outlet 5 a of the reaction can 5, and an airbag 9 in the case 8. The structure is folded and stored. Hooks 10 are attached to the front and rear surfaces of the case 8. The inflator 4 used in this embodiment has a normal output.
[0024]
A rectangular opening / closing door portion 11 is formed on the instrument panel 1 corresponding to the upper side of the airbag module 3. The open / close door 11 is defined by a rectangular cleavage groove 12 formed on the back surface of the instrument panel 1. The cleavage groove 12 is a cutting groove that is post-processed by a rotary blade (such as a milling blade) after the instrument panel 1 is molded. Therefore, no gloss unevenness occurs on the surface of the instrument panel 1.
[0025]
A soft resin backing member 13 is coupled to a portion corresponding to the opening / closing door portion 11 on the back surface of the instrument panel 1. The backing member 11 is a TPO resin injection-molded product having a flexural modulus of 2800 kgf / cm ² . As the material of the backing member 11, in addition to the TPO resin, various soft elastomer resins called abbreviations such as TPU, TPE, SES, SEBS are suitable, and the flexural modulus is 6000 kgf / cm ² or less ( Preferably, 4500 kgf / cm ² or less) is suitable.
[0026]
The backing member 13 is larger in size than the opening / closing door portion 11, and a plurality of coupling points 14 are set on the inside and outside of the cleavage groove 12. This joining point 14 is due to the ultrasonic welding horn 15 (see FIG. 6), and is immersed in the instrument panel 1 from the backing member 13 (see FIG. 5), and its boundary surface is corrugated to form resins. Has increased the binding power. Therefore, the matte texture on the surface of the instrument panel 1 is not affected. In addition, since many coupling points 14 can be set at free locations of the backing member 13, the coupling force between them can be sufficiently increased.
[0027]
Each cylindrical tubular body 16 is formed at a position close to the outside of the cleavage groove 12 in the backing member 13, and front and rear facing surfaces thereof are a pair of front and rear mounting pieces 17 and 18. Since the backing member 13 is made of resin, it is easy to integrally form the mounting pieces 17 and 18. Each of the mounting pieces 17 and 18 has a mounting hole 19 in which the hook 10 of the airbag module 3 is locked.
[0028]
The mounting pieces 17 and 18 are formed at a predetermined angle θ1 with respect to the instrument panel 1. This angle θ1 is different from the die cutting angle θ2 (about 25 degrees) when the instrument panel 1 is molded, and is optimal for holding the airbag module 3 and guiding the airbag 9 in the deployment direction. It is set to an angle.
[0029]
Since the backing member 13 is separate from the instrument panel 1, the angle θ <b> 1 of the mounting pieces 17, 18 can be freely set regardless of the die cutting angle θ <b> 2 of the instrument panel 1. Further, since the attachment pieces 17 and 18 are formed as the front and rear facing surface portions of the cylindrical body 16, the strength of the attachment pieces 17 and 18 is increased, the support strength of the airbag module 3 is improved, and the airbag is improved by the cylindrical body 16. The function of guiding the expansion direction of 9 is also improved. Furthermore, since the mounting pieces 17 and 18 are formed integrally with the backing member 13, the number of parts is not increased.
[0030]
A U-shaped cut portion 20 is formed at a portion corresponding to the cleavage groove 12 of the backing member 13, leaving the front side portion. The cutting portion 20 is formed in a slit shape with a small width. A portion of the backing member 13 corresponding to the front side portion of the cleavage groove 12 is a curved hinge portion 21 straddling the cleavage groove 12.
[0031]
Next, the actual deployment behavior of the airbag 9 will be described. When the automobile collides, gas is ejected from the inflator 4 to the airbag 9. The airbag 9 is inflated in the case 8, and the backing member 13 and the opening / closing door portion 11 are pushed upward by the expansion force F thereof. At this time, the tear grooves 12 on the rear side and the left and right sides are not covered with the backing member 13, so that the inflation force F of the airbag 9 acts directly and is easily broken. Further, although the front cleavage groove 12 is covered by the hinge portion 21 of the backing member 13, since the backing member 13 is a soft resin, it is deformed flexibly by the expansion force F of the airbag 9, and thus corresponds. An expansion force F is exerted on the cleavage groove 12. Therefore, the cleavage groove 12 in this portion is also easily broken. For this reason, even in the inflator 4 having a normal output, the cleavage groove 12 can be reliably broken and the open / close door portion 11 can be separated from the instrument panel 1.
[0032]
In addition, in this embodiment, since the attachment pieces 17 and 18 are in a position close to the cleavage groove 12, the attachment pieces 17 and 18 can suppress the upward movement of the proximity position of the cleavage groove 12, and the airbag 9 can be inflated. The force concentrates on the cleavage groove 12. Therefore, the opening / closing door portion 11 is further easily broken.
[0033]
The opening / closing door portion 11 separated from the instrument panel 1 is rotated and opened rearward around the hinge portion 21 of the backing member 13, and the airbag 9 is opened from the opening of the portion where the opening / closing door portion 11 is removed. It can be deployed in the passenger compartment to protect the passengers. At this time, since the hinge portion 21 of the backing member 13 has a curved shape, the airbag 9 is deformed toward the cleavage groove 12 at the initial stage of inflation, but the curved shape is restored immediately after opening and closing. The hinge portion 21 is prevented from being sharpened when the door portion 11 is opened, and the airbag 9 is brought into contact with the airbag 9 in a curved state, thereby promoting the smooth deployment of the airbag 9.
[0034]
FIG. 7 is a diagram showing a second embodiment of the present invention. The backing member 22 of this embodiment includes an outer portion 23 and an inner portion 24 with the cleavage groove 12 as a boundary. The outer portion 23 includes a cylindrical body 16 having mounting pieces 17 and 18 formed on the front and rear sides, and the inner portion 24 is an opening / closing door through a hinge portion 26 to a coupling piece 25 to be superposed on the front mounting piece 17. A portion 22a coupled to only the portion 11 is included. An end portion 22b close to the cutting portion 20 at the rear end of the backing member 22 is formed long and covers the corresponding cleavage groove 12 from the lower side. However, since this portion is also deformed flexibly, the corresponding cleavage groove 12 is formed. Make sure to break.
[0035]
By dividing the backing member 22 in this way, the backing member 22 can be easily formed. Even if the backing member 22 is divided into two parts, the backing member 22 remains a single part including the mounting pieces 17 and 18, which can contribute to a reduction in the number of parts.
[0036]
8 and 9 are views showing a third embodiment of the present invention. In this embodiment, a central groove 12 a that divides the opening / closing door 31 forward and backward is formed in the center of the cleavage groove 12, hinge portions 28 and 29 are formed in the mounting pieces 17 and 18 of the backing member 27, and A cutting portion 30 was formed in a portion corresponding to the central groove 12a in the center of the member 27. With such a structure, the open / close door portion 31 can be formed as a so-called “double door”.
[0037]
【The invention's effect】
According to this invention, since the backing member is made of a soft resin having a strength capable of deforming due to the inflating force of the airbag and exerting the inflating force on the tearing groove, the tearing groove is easily broken, and the inflator is large and has high output There is no need to do. Therefore, it is advantageous in terms of weight and cost.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view of an instrument panel showing an airbag apparatus according to a first embodiment of the present invention.
FIG. 2 is a partially broken perspective view showing the structure of an opening / closing door and a backing member according to the first embodiment.
FIG. 3 is a cross-sectional view showing the structure of an opening / closing door and a backing member according to the first embodiment.
FIG. 4 is a cross-sectional view showing the backing member in a state of being deformed by the inflation force of the airbag.
FIG. 5 is a partially broken perspective view showing the structure of a coupling point.
FIG. 6 is a perspective view showing a tip of an ultrasonic welding horn.
FIG. 7 is a cross-sectional view showing the structure of an opening / closing door and a backing member according to a second embodiment.
FIG. 8 is a cross-sectional view showing a structure of an opening / closing door and a backing member according to a third embodiment.
FIG. 9 is a plan view showing a cleavage groove according to a third embodiment.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Instrument panel 3 Air bag module 4 Inflator 9 Air bag 11, 31 Opening / closing door part 12 Cleaving groove 13, 22, 27 Backing member 16 Cylindrical body 17, 18 Attachment piece 20, 30 Cutting part 21, 26, 28, 29 Hinge part θ1 Forming angle of mounting piece θ2 Die angle F of instrument panel F Inflating force of airbag

Claims (7)

With installing the airbag module housing the airbag and the inflator on the back of the instrument panel made of resin, said to form a closed loop cleavage groove on the back surface of the instrument panel corresponding to the air bag door portion Partition
On the back side of the door portion, the larger backing member than the door unit, with binding to the inside and outside of the door section, the outer section than the opening and closing door portion of the backing member, the air A pair of front and rear mounting pieces for locking the upper portion of the bag module is formed at a predetermined angle with respect to the backing member,
It said backing member, a hinge portion corresponding to one front side or rear side of at least one of the cleavage groove is provided, and the other to provide a cutting portion, centered on the said hinge portion, of the air bag An automotive airbag device that enables opening of an opening / closing door portion separated from the instrument panel by an expansion force,
The hinge portion of the backing member is an automobile air bag, wherein the deformed by the expansion force of the airbag covering the cleavage groove is made soft resin Oyoboseru strength expansion force to the rupturing groove apparatus. An automobile airbag device according to claim 1,
An automotive airbag device, wherein the backing member has a flexural modulus of 6000 kgf / cm ² or less (preferably 4500 kgf / cm ² or less). An automobile airbag device according to claim 1 or claim 2,
An air bag device for an automobile, wherein the mounting piece is in a position close to the cleavage groove. The automobile airbag device according to any one of claims 1 to 3,
An automobile airbag device, wherein a pair of front and rear mounting pieces are formed as front and rear facing surface portions of a cylindrical body formed outside a cleavage groove of a backing member. The automobile airbag device according to any one of claims 1 to 4,
An automobile airbag device, wherein the cleavage groove is a cutting groove processed after molding an instrument panel. An automobile airbag device according to any one of claims 2 to 5,
An automotive airbag apparatus, wherein the instrument panel and the backing member are joined by ultrasonic horn welding. The airbag apparatus for an automobile according to any one of claims 2 to 6,
An automotive airbag apparatus, wherein a hinge portion of a backing member has a curved shape straddling a cleavage groove.

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