JP4285742B2 - Air grid structure - Google Patents

Description

  The present invention relates to a seamless airbag grid structure mounted on an instrument panel.

  The vehicle is equipped with a passenger seat airbag module to protect passengers in the passenger seat. The passenger seat airbag module is disposed on the back side of an instrument panel (hereinafter referred to as instrument panel).

  As disclosed in Patent Document 1, a rectangular groove is formed on the back surface of the instrument panel so as to surround a portion corresponding to the airbag module, and is thin along this groove. A portion inside the groove, that is, a portion corresponding to the airbag module is provided as an airbag grid, and a portion outside the groove is provided as an instrument panel main body (hereinafter referred to as an instrument panel main body). The front side of the air grid and the instrument panel body are continuous, and the boundary line (partition line or tear line) is not visible from the front side (vehicle compartment side), and the appearance is good. Such a structure is generally referred to as seamless.

  On the back surface of the instrument panel body, a resin support frame is vibration welded so as to surround the air grid. A hinge member is integrally formed on the support frame. The plate portion of the hinge member is vibration welded to the airbag grid, and a curved hinge portion is formed between the plate portion and the main body portion of the support frame.

When the airbag is inflated and the airbag grid is pushed at the time of a vehicle collision, the thin portion of the partition line is broken, the airbag grid is removed and an opening is formed, and the airbag that has expanded from this opening jumps out toward the passenger seat. It has become. Since the support frame is fixed to the instrument panel main body and the airbag module is fixed, the instrument panel main body is prevented from inflating when the airbag is operated, so that the partition line is reliably broken. Since the air bag grid is supported by the instrument panel via a hinge member, the air grid is prevented from scattering and is opened like a door around the hinge portion of the hinge member.
Japanese Patent Laid-Open No. 2000-71924

  In the configuration of Patent Document 1, since the support frame and the hinge member are integrated and formed of the same resin, there are the following drawbacks. That is, the support frame requires high rigidity to fix the airbag module. However, if a resin having high rigidity is used, the hinge function of the hinge member is lowered, and the opening operation of the airbag grid is hindered. On the contrary, if a resin having low rigidity and elasticity is used, the hinge function of the hinge member can be satisfactorily performed, but the airbag module cannot be stably fixed. In addition, since the resin having low rigidity and elasticity is expensive, the use of a large amount of this resin increases the cost.

The present invention has been made to solve the above problems, and by forming a groove on the back surface of the instrument panel so as to surround a portion corresponding to the airbag module, a portion inside the groove is formed as an air bag grid. In an air bag grid structure in which a portion outside the groove is provided as an instrument panel body, a hinge member made of a resin having a relatively low rigidity, and a resin having a relatively high rigidity that is a separate member from the hinge member and a supporting frame consisting of, and the hinge member is the first portion of the vibration welding is a plate shape on the back surface of the airbag lid, a second portion of the vibration welded plate-shaped on the back of the instrument panel main body, The first and second portions are connected to the groove, and the support frame is It has a body portion which forms a U-shaped cross section with forming a frame shape along the entire circumference of the outer peripheral edge of Aba' grid, and a flange portion extending from the upper edge of the outer peripheral wall of the body portion on the opposite side of the airbag lid, this A collar portion is vibration welded to the back surface of the instrument panel body, the body portion covers the groove of the instrument panel, the hinge portion and the second portion of the hinge member, and the airbag module is attached to the body portion of the support frame. The case is fixed , a part of the case enters the main body portion and is separated from the airbag grid, and the surface on the airbag grid side of the inner peripheral wall of the main body portion is lateral to the airbag of the airbag module. It is provided as a guide surface that regulates the swelling to the surface .
Here, the terms “relatively high and low” are used in comparison with the support frame and the hinge member.

According to the above configuration, the hinge member and the support frame are separate members, and the hinge member is made of a resin having relatively low rigidity. Therefore, a favorable hinge function can be exhibited when the air bag grid is opened. In addition, since the support frame is made of a relatively high-stiffness resin, the airbag module can be stably fixed. As a result, the inflation of the instrument panel body can be suppressed during the airbag operation, and the break at the partition line can be ensured. . As a result, it is possible to ensure a smooth opening operation of the airbag grid.
Further, since the support frame covers the hinge portion of the hinge member, the airbag is not applied to the hinge portion when the airbag is inflated, and the inflation force of the airbag is concentrated and applied to the airbag grid. Can be further ensured.
More preferably, the guide surface of the main body portion is inclined so as to gradually reduce the opening area of the main body portion toward the airbag grid.

Preferably, the case of the airbag module is made of metal, and a mounting flange portion is provided on the case, and a plurality of boss portions are formed on the lower surface of the main body portion of the support frame at intervals around the entire circumference. A screw hole is formed in the boss portion, and the mounting flange portion of the case is fixed to the boss portion of the main body portion of the support frame by a screw screwed into the screw hole.
According to this, the airbag module and the instrument panel main body can be firmly fixed to each other through the support frame with screws, and the swelling of the instrument panel main body during the operation of the airbag can be more reliably suppressed. Moreover, since the screw hole is formed in the support frame having high rigidity, the screw can be screwed in without crushing the screw thread. Furthermore, since the airbag module, the resin support frame, and the instrument panel can be separated by removing the screws, recycling is easy.

  Preferably, a locking rib standing from the instrument panel main body is formed on the edge of the second portion of the hinge member, and a receiving portion for locking the locking rib is formed on the support frame. According to this, the welding area of the 2nd part of a hinge member can be narrowed, and a support frame can be reduced in size. Even if the welding area peels off when the airbag is inflated because the welding area is small, the hinge member can be held on the support frame by the locking action of the locking rib and the receiving portion, and the scattering of the airbag grid is reliably prevented. Because it can.

  As described above, the present invention can ensure a smooth opening operation of the air bag grid.

  Hereinafter, a seamless airbag grid structure according to an embodiment of the present invention will be described with reference to the drawings. As shown in FIG. 2, the instrument panel 10 of the present embodiment is called a hard instrument panel, and is formed in a single layer by injection molding a resin.

  On the back side of the instrument panel 10, an airbag module 20 is disposed facing the passenger seat. A groove 15 is formed on the back surface of the instrument panel 10 so as to surround the portion 11 corresponding to the airbag module 20 and is thin. This part 11 is provided as an air bag grid. In the instrument panel 10, a portion outside the groove 15 is provided as an instrument panel main body 12. A thin line corresponding to the groove 15 is called a partition line or a tier line.

  The said groove | channel 15 draws a long rectangle in the left-right direction of a vehicle, as shown in FIG. Further, an auxiliary groove 16 extending linearly is formed on the back surface of the airbag grid 11 to form a thin partition line. The auxiliary groove 16 extends along two long sides of the rectangle drawn by the groove 15 and intersects the two short sides of the rectangle. The airbag grid 11 has a pair of door portions 11 a and 11 a that are divided forward and backward by the auxiliary groove 16.

  The airbag module 20 has a metal case 21 opened on the airbag grid 11 side, and accommodates an actuator and an airbag (both not shown) in the case 21. The case 21 is fixed to the steering beam 50 (vehicle body side fixing system member) via a metal bracket 22.

  Next, the hinge means for the airbag grid 11 will be described. The hinge means includes two hinge members 30 and 30 corresponding to the two door portions 11 a and 11 a of the airbag grid 11. These hinge members 30 and 30 are arranged on the back side of the instrument panel 10 and play a role of connecting the door portions 11a and 11a of the airbag grid 11 to the instrument panel body 12, and have a relatively low rigidity and elasticity, for example, olefin-based heat. It is made of a plastic elastomer.

  The hinge member 30 includes an elongated substantially flat plate-like wide plate portion 31 (plate-like first portion) extending in the left-right direction of the vehicle, and a substantially flat plate-like narrow plate portion 32 (plate-like first portion) extending in the same direction. 2 parts) and an elongated curved hinge part 33 connecting these plate parts 31 and 32. The wide plate portion 31 is attached to the door 11a by vibration welding, and the narrow plate portion 32 is attached to the instrument panel body 12 by vibration welding. The hinge portion 33 extends along the groove 15 located at the front and rear of the vehicle. A locking rib 34 is formed on the edge of the plate portion 32 (the edge on the opposite side of the hinge portion 33) so as to stand up from the instrument panel main body 12.

Further, on the back side of the instrument panel 10, a support frame 40 surrounding the airbag grid 11 is disposed along the groove 15 (along the outer peripheral edge of the airbag grid 11). The support frame 40 is made of polypropylene mixed with a relatively high-rigidity resin such as talc filler, and has a flat rectangular frame shape. The main body portion 41 of the support frame 40 has a U-shaped cross section and covers the groove 15 of the instrument panel 10 and the hinge portion 33 of the hinge member 30.

  A flange 42 is formed on the outer peripheral edge of the main body 41, and the flange 42 is attached to the back surface of the instrument panel main body 12 by vibration welding. The front and rear flanges 42 are welded adjacent to the plate portion 32 of the hinge member 30. A plurality of fins 43 are formed inside the front and rear portions of the main body 41 at appropriate intervals, and the locking ribs 34 of the hinge member 30 are locked to the protrusions 43a (receiving portions) of the fins 43. It has come to be.

  The airbag module 20 enters the space inside the main body 41, and the inner peripheral surface of the main body 41 is a slightly inclined guide surface 41a. A plurality of boss portions 44 are formed on the lower surface of the main body portion 41 at appropriate intervals over the entire circumference, and screw holes 44 a are formed in the boss portions 44. A plurality of mounting flanges 24 projecting from the outer periphery of the case 21 of the airbag module 20 are applied to the lower surface of the boss portion 44, and are fixed by screws 55 screwed into the screw holes 44a. Accordingly, the instrument panel 10 is fixed to the airbag module 20 through the support frame 40 without rattling, and is further firmly connected to the steering beam 50 via the airbag module 20.

  In the above configuration, when the actuator of the airbag module 20 operates to inflate the airbag in response to a vehicle collision, the airbag pushes the airbag grid 11 with a strong impact force. Then, as shown in FIG. 4, the thin portions corresponding to the grooves 15 and 16 are broken, and the two door portions 11 a and 11 a of the airbag grid 11 are separated from each other and also from the instrument panel main body 12. At this time, since the door portions 11 a and 11 a are connected to the instrument panel body 11 by the hinge member 30, the door portions 11 a and 11 a rotate about the hinge portion 33.

  As described above, the airbag grid 11 is divided into the two door portions 11a and 11a and opened in a double-open manner, whereby an opening is formed in the instrument panel body 12, and the inflated airbag is ejected through the opening. At this time, the hinge portion 33 of the hinge member 30 extends to ensure the opening operation of the door portions 11a and 11a.

  In the present embodiment, the hinge member 30 is made of a resin having lower rigidity and elasticity than the support frame 40, so that the hinge function can be satisfactorily exhibited and the opening operation of the airbag grid 11 can be performed smoothly. Further, since the locking rib 34 of the hinge member 30 is locked to the protrusion 43a of the support frame 40, even if the welded portion between the plate portion 32 of the hinge member 30 and the instrument panel body 12 is peeled off during the airbag operation, the hinge member 30 can be prevented from falling off, and as a result, scattering of the door portions 11a and 11a can be prevented.

  Further, the instrument panel main body 12 is fixed to the airbag module 20 via the support frame 40 without rattling, and is further firmly connected to the steering beam 50 via the support frame 40, so that the inflated airbag is the airbag grid. When hitting 11, it is prevented from bulging and breaking. Further, since the groove 15 and the hinge portion 33 of the hinge member 30 are covered with the support frame 40, the airbag that has been inflated does not hit these portions during the airbag operation, and therefore the inflation force by the airbag is limited to the airbag grid 11 only. To be concentrated. As described above, the instrument panel body 12 is prevented from being inflated or cracked, and the expansion force of the airbag is concentrated on the airbag grid 11 so that the stress is concentrated on the grooves 15 and 16 and the breakage is reliably ensured. be able to.

  Since the guide surface 41a of the support frame 40 is inclined so as to regulate the lateral expansion of the inflating airbag and gradually reduce the opening area toward the instrument panel 10, the orientation of the airbag toward the airbag grid 11 is improved. Thus, the concentration of the expansion force on the airbag grid 11 can be further improved.

The present invention is not limited to the above-described embodiments, and various aspects are possible. The airbag grid may be composed of a single door portion. In this case, for example, the side edge farther from the passenger seat in the airbag grid and the instrument panel body are connected by a hinge member.
The second part of the hinge member may be fixed to the support frame by vibration welding or the like, and thereby indirectly fixed to the back side of the instrument panel.
The support frame may have a case shape to accommodate and fix the airbag module. In this case, the lower end portion of the support frame is fixed to the steering beam via the bracket.

It is a top view of the air grid structure which makes one Embodiment of this invention. It is a longitudinal cross-sectional view of the airbag grid structure which follows the II-II line in FIG. It is a longitudinal cross-sectional view of the airbag grid structure which follows the III-III line in FIG. It is a principal part expansion longitudinal cross-sectional view of the airbag grid structure which shows the state at the time of airbag operation | movement.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Instrument panel 11 Air bag grid 12 Instrument panel main body 15 Groove 20 Air bag module 21 Case 24 Mounting collar 30 Hinge member 31 Plate part (plate-shaped 1st part)
32 Plate part (plate-like second part)
33 Hinge part 34 Locking rib 40 Support frame 41a Guide surface 43a Protrusion (receiving part)
44a Screw hole 50 Steering beam (vehicle side fixed system member)
55 screws

Claims (4)

By forming a groove on the back of the instrument panel so as to surround the portion corresponding to the airbag module, the portion inside the groove is provided as an airbag grid, and the portion outside the groove is provided as the instrument panel body. In the air bag grid structure
A hinge member made of a resin having a relatively low rigidity, and a support frame made of a resin having a relatively high rigidity that is a separate member from the hinge member,
The hinge member includes a plate-shaped first portion vibration welded to the back surface of the airbag grid, a plate-shaped second portion vibration welded to the back side of the instrument panel body, and the first and second portions. A hinge portion positioned corresponding to the groove,
The support frame has a frame shape that extends along the entire circumference of the outer peripheral edge of the airbag grid and has a U-shaped cross section, and a flange that extends from the upper edge of the outer peripheral wall of the main body portion to the opposite side of the airbag grid. And the flange portion is vibration welded to the back surface of the instrument panel body, and the body portion covers the groove of the instrument panel and the hinge portion and the second portion of the hinge member,
Above the main body portion of the support frame case of the airbag module is fixed, a part of the case is spaced apart from the air bag lid with enters the body portion, the surface of the airbag lid side of the inner peripheral wall of the body portion Is provided as a guide surface that restricts the lateral expansion of the airbag of the airbag module . The air bag grid structure according to claim 1, wherein the guide surface of the main body portion is inclined so as to gradually reduce the opening area of the main body portion toward the air bag grid. The case of the airbag module is made of metal, and a mounting flange portion is provided on the case, and a plurality of boss portions are formed on the lower surface of the main body portion of the support frame at intervals along the entire circumference. The air bag according to claim 1 or 2 , wherein a screw hole is formed, and the mounting flange portion of the case is fixed to a boss portion of the main body portion of the support frame by a screw screwed into the screw hole. Grid structure. A locking rib standing from an instrument panel main body is formed on an edge of the second portion of the hinge member, and a receiving portion for locking the locking rib is formed on the support frame. airbag lid structure according to any one of claims 1 to 3.

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