Patent Publication Number: US-2010109365-A1

Title: Glove box door

Description:
The Present application claims priority from Japanese Patent Application No. 2008-280151 of Shibata et al., filed on Oct. 30, 2008, the disclosure of which is hereby incorporated into the present application by reference. 
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to a door of a glove box of a vehicle that openeably closes off an opening located at the rear of the glove box. More particularly, the present invention relates to a glove box door that incorporates an airbag apparatus for knee protection. 
     2. Description of Related Art 
     JP 2002-347565A and JP 2002-356137A are illustrative of a glove box that incorporates an airbag apparatus for knee protection. The glove boxes shown in these references are so-called “no lid” type glove box that has an opening on top and no lid, and is rotatable about the bottom region. The box is pulled out by rotating the box about the bottom region. The airbag apparatus is mounted on a rear wall of the glove box so an airabg is deployable rearward from the rear wall. 
     However, since the rear wall of the glove box is formed of solid synthetic resin, the above configuration has a problem in terms of weight reduction. 
     U.S. Pat. No. 6,971,667 discloses a glove box of “with lid” type that includes a storage bin and a lid (door) which incorporates an airbag apparatus therein, although this apparatus is not intended to bolster knees of a passenger by an airbag in itself. The door of the glove box includes an outer panel and an inner panel, and the airbag is housed in a space between the outer panel and inner panel. When activated, the airbag is inflated and pushes out the outer panel rearward so the outer panel supported by the airbag bolsters the knees. 
     In the door of the above glove box, the housing space of the airbag extends over a wide area between the outer panel and inner panel, both in a vertical and left and right direction. This configuration hinders rigidity of the glove box door. 
     It is conceivable in this type of glove box assembly that the airbag apparatus is located between an outer panel and inner panel of the glove box door so as to deploy an airbag from the outer panel. In this case, however, it is expected, in operation, that an intense tensile force acts on a housing portion of the airbag and on a door that allows airbag emergence, such that the outer panel and inner panel are disconnected and outer panel slips from the inner panel toward an interior of vehicle, thereby hindering the opening of the door and deployment of the airbag. 
     SUMMARY OF THE INVENTION 
     An object of the present invention is to provide a door of a glove box with an airbag apparatus that is rigid and light in weight, and deploys an airbag in a smooth fashion. 
     The door of a glove box for installation in front of a seat of a vehicle incorporates an airbag apparatus for knee protection. The glove box door includes an outer panel constituting a rear outer circumferential wall of the glove box door and an inner panel coupled to the outer panel and constituting a front outer circumferential wall of the glove box door. The airbag apparatus is located between the outer panel and inner panel. The outer panel includes an outer door region for opening to allow airbag emergence and is provided therearound with a weakened tearable portion. The glove box door further includes a plurality of reinforcing ribs extending between and connecting the outer panel and inner panel around the airbag apparatus in such a manner as to form void spaces between the outer panel and inner panel. 
     The airbag apparatus includes an inflatable airbag for emergence and deployment from the outer door region of the outer panel, an inflator that feeds inflation gas to the airbag, a case that houses and holds the airbag and inflator, a holder coupled to the outer panel and holding the case in order to mount the case to the outer panel, and a pair of mounting elements that are assembled with the holder in such a manner as to be prevented from forward or backward movement and assist the mounting of the case to the outer panel. The outer panel and holder are fabricated of synthetic resin, and the outer panel is fabricated of rigid synthetic resin relative to the holder. 
     The case includes a circumferential wall, a front wall that closes off the front side of the circumferential wall, an opening that opposes the front wall for allowing airbag emergence, and a pair of mounting tongues that are formed on opposite sides of the circumferential wall. 
     The holder includes a circumferential wall that is mounted around the case and extends in a generally anteroposterior direction, a holding panel that is joined with and extends from the rear end of the circumferential wall in such a manner as to cover the opening of the case, the holding panel being coupled to and holding the outer door region of the outer panel and provided with a flexible hinge located proximate the rear end of the circumferential wall, and a joint flange extending from the rear end of the circumferential wall and coupled to an area of the outer panel encircling the outer circumference of the tearable portion. 
     The mounting tongues of the case are secured to the mounting elements that are assembled with the holder by fixing means and thus the case is mounted to the outer panel. 
     The outer door region of the outer panel and the holding panel of the holder form, in combination, a door that covers the opening of the case and opens at airbag deployment due to tear of the tearable portion of the outer door region to provide an emergence opening that allows emergence of the airbag. 
     When the airbag apparatus installed on the glove box door of the invention is activated, the airbag inflates with inflation gas from the inflator and pushes the door that is comprised of the outer door region of the outer panel and the holding panel of the holder. Then the tearable portion formed around the outer door region gets torn and the door opens about the hinge and allows airbag emergence. 
     At this time, the door comprised of the outer door region of the outer panel and the holding panel of the holder is pushed rearward, i.e., away from the case, by the airbag. On the contrary, the case is subjected to a reaction force of the airbag acting forward. However, the mounting tongues formed on opposite sides of the circumferential wall of the case are secured to the mounting elements that are assembled with the holder in such a manner as to be prevented from moving forward or backward. Accordingly, the case is prevented from moving forward by the holder. Moreover, the area of the outer panel surrounding the tearable portion is prevented from moving backward since the joint flange of the holder is joined to the fore face of that area and holds that area. That is, it is prevented that the area of the outer panel surrounding the tearable portion and mounting tongues of the case move away from each other in an anteroposterior direction. With this configuration, if pushed by the airbag, the outer door region of the outer panel smoothly gets separated from the surrounding area due to tear of the tearable portion, and opens around the hinge of the holder together with the holding panel. 
     As a result, the airbag smoothly emerges from the emergence opening provided by the opening of the door and deploys rearward without being adversely affected by the outer panel since the outer panel is prevented from moving rearward. 
     On the other hand, the case is secured to the holder and the holder is coupled to the outer panel by the joint flange. That is, the case is mounted to the outer panel through intermediary of the holder, but is not directly mounted to the inner panel. Accordingly, even when subjected to a forward force upon airbag deployment, the case will not so act as to cause disconnection of the inner panel from the outer panel. Furthermore, the outer panel is fabricated of rigid synthetic resin relative to the holder, which is required to be soft in view of flexibility of the hinge, and therefore, the outer panel holds the case through intermediary of the holder in a stable manner. 
     Further, after airbag deployment, although the inertia force of the airbag pulls the case to the rear, the mounting elements to which the mounting tongues of the case are secured to are prevented from moving rearward by the holder, and are secured to the rigid outer panel by intermediary of the holder. Thus the case is stably held by the outer panel as well after deployment of the airbag. 
     Moreover, a plurality of the reinforcing ribs extend between and connect the outer panel and inner panel around the airbag apparatus in such a manner as to form a plurality of void spaces between the inner and outer panels. The void spaces conduce to lighten the weight of the glove box door and the ribs improve flexural and torsional rigidity of the glove box door. 
     Therefore, the glove box door of the invention is rigid and light in weight although having an airbag apparatus, and deploys an airbag in a smooth fashion. 
     In the glove box door of the invention, it is desired that each of the mounting elements is formed into a generally plate shape and the holder includes a pair of mounting beds each of which includes a front regulating region that regulates movement of the mounting element on the front side and a rear regulating region that regulates movement of the mounting element on the rear side so each of the mounting elements is inserted into a space formed between the front regulating region and rear regulating region and thus attached to the holder. 
     With this configuration, each of the mounting elements is easily assembled with the holder only by insertion into the space between the front regulating region and rear regulating region of corresponding mounting bed. The mounting elements assembled with the holder are clamped by the front regulating regions and rear regulating regions and prevented from forward or rearward movement. Thus the mounting tongues of the case are secured to the mounting elements in a stable manner. 
     In this case, it is desired that the front regulating region of each of the mounting beds includes a front wall that is connected to the circumferential wall of the holder and regulates movement of the mounting element on the front side, the front wall including a round through hole for receiving a bolt acting as the fixing means, and a pair of support walls that extend from opposite ends of the front wall toward the joint flange and coupled to the joint flange while being connected to the circumferential wall of the holder, the front regulating region thus having a “U” shaped section, and that each of the mounting elements includes a screw hole for receiving the bolt and the rear regulating region of each of the mounting beds is coupled to the circumferential wall and joint flange of the holder and supports the vicinity of the screw hole of the mounting element at more than one locations from the rear. 
     With this configuration, both of the front regulating region and rear regulating region of each of the mounting beds are coupled to both of the joint flange and circumferential wall. The joint flange extends vertically along the tearable portion of the outer panel whereas the circumferential wall of the holder extends in an anteroposterior direction in such a manner as to surround the case. Coupled to these two parts of the holder extending mutually orthogonally, the front regulating region and rear regulating region are enhanced in rigidity. Clamped by these front regulating region and rear regulating region, the mounting elements are positioned in a further stable fashion. Moreover, the front wall of the front regulating region is prevented from moving forward, i.e. moving away from the outer panel, by the support walls coupled to the circumferential wall and joint flange at opposite ends while abutting against an entire fore face of the mounting element. Therefore the front wall securely prevents the mounting element from moving forward. In addition, the rear regulating region are coupled to the circumferential wall and joint flange and supports the vicinity of the screw hole of the mounting element at more than one positions from the rear. Therefore the rear regulating region securely prevents the mounting element from moving rearward. 
     The inner panel of the glove box door may be formed of a single plate-shaped material. It may also be formed of more than one split parts. The former configuration will facilitate assembling of the glove box door compared to the latter because it unnecessitates a step for coupling the split parts. 
     If the inner panel is formed of more than one split parts, the inner panel can be comprised of, for instance, a cover panel that is fabricated of synthetic resin and located in front of the airbag apparatus and a peripheral panel that is fabricated of synthetic resin as well and located around the cover panel. The cover panel and peripheral panel are coupled together. In this case, the reinforcing ribs are formed integrally with either the outer panel or the peripheral panel of the inner panel and welded to the peripheral panel or the outer panel so the outer panel and peripheral panel are coupled together. 
     With this configuration, the outer panel and inner panel are easily coupled together by welding the reinforcing ribs extending from either the outer panel or peripheral panel of the inner panel to the counterpart by vibration welding or the like. Additionally, this configuration provides firm connection between the reinforcing ribs, outer panel and inner panel, thus preventing the inner panel from moving away from the outer panel and enhancing rigidity of the glove box door. Although the outer panel and inner panel are welded together by vibration-welding or the like, the welded portions will stay intact upon airbag deployment since the inner panel is not subjected to forward pressing force of the case as described above. 
     Furthermore, if at least part of the reinforcing ribs located in the vicinity of the holder is integral with the outer panel, the rigidity of the outer panel in the vicinity of the holder will be enhanced and thus assuring steady operation of the airbag apparatus. 
    
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
         FIG. 1  is a perspective view of a glove box door having an airbag apparatus for knee protection, as is mounted on a vehicle; 
         FIG. 2  is a schematic vertical section of an instrument panel of the vehicle where the glove box door of  FIG. 1  is installed, taken along an anteroposterior direction; 
         FIG. 3  is a schematic vertical section of the glove box door of  FIG. 1  as is mounted on the vehicle; 
         FIG. 4  is a schematic enlarged vertical section of the glove box door of  FIG. 1  as is mounted on the vehicle; 
         FIG. 5  is a schematic horizontal section showing the way an inflator and a case of the airbag apparatus are fastened together; 
         FIG. 6  is a schematic perspective view of the inflator and case of  FIG. 5 ; 
         FIG. 7  is a partial perspective view of a holder and its vicinity; 
         FIG. 8  is a schematic enlarged vertical section of a mounting bed of the holder of  FIG. 8  and its vicinity; 
         FIG. 9  is a schematic horizontal section of the glove box door taken along line IX-IX of  FIG. 8 ; and 
         FIG. 10  is a schematic vertical section of a modification of the glove box door. 
     
    
    
     DESCRIPTION OF PREFERRED EMBODIMENTS 
     Preferred embodiments of the present invention are described below with reference to the accompanying drawings. However, the invention is not limited to the embodiments disclosed herein. All modifications within the appended claims and equivalents relative thereto are intended to be encompassed in the scope of the claims. 
     A glove box door  20  embodying the present invention includes a built-in knee-protecting airbag apparatus S and is located on the rear side of a glove box  13  on the lower side of the instrument panel or dashboard  4  and in front of a front passenger&#39;s seat. 
     Up/down, front/rear and left/right directions in this specification are intended to refer to up/down, front/rear and left/right directions in a condition that the glove box door  20  is closing an opening  14   a  of the glove box  13 . 
     Referring to  FIG. 2 , the glove box  13  is of so-called “with lid” type including a box body  14  fabricated of rigid synthetic resin such as polypropylene and a door  20  that lids the opening  14   a  of the box body  14  in an openable fashion. The opening  14   a  is located on the rear side of the box body  14 . The box body  14  is formed into a generally rectangular parallelepiped box including a circumferential wall  15  having a generally square cylindrical shape and a front wall  16  located at the front end of the circumferential wall  15 . The circumferential wall  15  includes a lower wall  15   a , an upper wall  15   b  facing the lower wall  15   a  above the lower wall  15   a , left and right side walls  15   d  connecting left and right ends of the lower wall  15   a  and upper wall  15   b  respectively and opposing each other in a left and right direction, and a rectangular opening  14   a  at the rear. The front wall  16  is coupled to front ends of the lower wall  15   a , upper wall  15   b  and side walls  15   d  and arranged generally vertically in such a manner as to oppose the opening  14   a . Each of the left and right side walls  15   d  includes proximate the bottom of the rear end region a hinge pin  17  about which the glove box door  20  rotates when opening. Each of the side walls  15   d  is further provided with an unillustrated bracket for attachment to the vehicle body structure  1  and an unillustrated recess for engagement with a latch formed on the glove box door  20  proximate the top of the rear end region. The hinge pins  17  are for engagement with a later-described outer panel  21  of the glove box door  20  and the above-described latches are formed on the outer panel  21  as well. 
     The upper wall  15   b  includes a joint lug  15   c  to be bolt  5  fixed to a joint tongue  4   a  of the dashboard  4  as shown in  FIG. 2 . This joint is covered by a decoration panel  6 . An undercover  11  is arranged below the glove box  13 . 
     When moved to shut the opening  14   a  of the box body  14 , the latches of the glove box door  20  described above are inserted into the recesses of the side walls  15   d  due to such biasing means as a spring, so that the door  20  keeps closing the opening  14   a  in a generally upright posture as shown in  FIGS. 1 to 4 . If the latches are disengaged from the recesses of the side walls  15   d  by pulling a lever  19  ( FIG. 1 ), the glove box door  20  rotates rearward about the lower end  20   b  pivoting about the hinge pins  17  as indicated by double-dashed lines in  FIG. 2 , so that the opening  14   a  appears. When the door  20  opens, an unillustrated projection formed in the vicinity of the lower end  20   b  abuts against a stopper formed on the box body  14 , thereby arranging the front plane  20   c  ( FIG. 2 ) of the door  20  generally horizontally. The projection extends forward from the outer panel  21  via a later-described inner panel  61 . Although not shown, a damping mechanism is mounted around the hinge pins  17  for suppressing abrupt opening of the door  20 . 
     The hinge pins  17 , lever  19 , unillustrated latches, projection, stopper and damping mechanism are known components of this kind of glove box. 
     As best shown in  FIG. 4 , the door  20  of the glove box  13  includes an outer panel  21  which forms an outer circumferential wall of the rear face  20   d  of the door  20  as closed and an inner panel  61  forming an outer circumferential wall of the front face  20   c . The door  20  has the knee-protecting airbag apparatus S between the outer panel  21  and inner panel  61 . A plurality of reinforcing ribs  59  extend between the outer panel  21  and inner panel  61  around the airbag apparatus S and provide void spaces  20   e  between the outer panel  21  and inner panel  61 . 
     The outer panel  21  includes an outer door  27  that covers the rear side of the airbag apparatus S and is pushed and opened by the airbag  71  at deployment and a surrounding region  22  that surrounds the outer door  27 . The surrounding region  22  includes a rear panel portion  23  that is located at the rear of the void spaces  20   e  and an outer peripheral region  24  that extends forward and butts against a later-described outer peripheral region  64  of the inner panel  61 . The rear panel portion  23  is integral with the numerous reinforcing ribs  59  that extend forward, i.e. toward the inner panel  61 , in the shape of plate or stick. Each of the ribs  59  is coupled to a later-described front panel portion  63  of the peripheral panel  62  of the inner panel  61  at the front end  59   a . In this specific embodiment, the front ends  59   a  of the ribs  59  are coupled to the front panel portion  63  by vibration welding. The outer panel  21 , including the ribs  59 , is fabricated of rigid synthetic resin such as filler-reinforced polypropylene for ensuring rigidity. 
     The outer door  27  includes an upper flap  28  and a lower flap  29  each having a rectangular plate shape. The flaps  28  and  29  are provided therearound with a tearable portion  26  which is so thin as to be torn when pushed by the airbag  71  under inflation. The tearable portion  26  is comprised of a continuous groove or a series of intermittent grooves formed on the front face of the outer panel  21 , and forms a “8” shape as viewed from the rear ( FIG. 1 ). The upper flap  28  is welded to a later-described upper section  41  of the holding panel  40  of the holder  33  by the fore face. When pushed by the airbag  71  at deployment, the upper flap  28  is separated from the rear panel portion  23  and lower flap  29  due to tear of the tearable portion  26  and opens upward together with the upper section  41 . The lower flap  29  is located below the upper flap  28  and welded to a later-described lower section  42  of the holding panel  40  by the fore face. When pushed by the airbag  71  at deployment, the lower flap  29  is separated from the rear panel portion  23  and upper flap  28  due to tear of the tearable portion  26  and opens downward together with the lower section  42  as indicated by double-dashed lines in  FIG. 4 . 
     The rear panel portion  23  includes a peripheral region  23   a  that surrounds the tearable portion  26 . As shown in  FIGS. 4 and 9 , the peripheral region  23   a  is a square annular region to which later-described joint flange  46  is connected. The joint flange  46  of this embodiment is vibration-welded to the peripheral region  23   a  as the holding panel  40  is welded to the outer door  27 . 
     As shown in  FIGS. 2 and 4 , the inner panel  61  includes a cover panel  66  that covers the front side of the airbag apparatus S and has a generally rectangular plate shape and a peripheral panel  62  that is located around the cover panel  66 . The cover panel  66  and peripheral panel  62  are fabricated of rigid synthetic resin such as filler-reinforced polypropylene for ensuring rigidity alike the outer panel  21 . As shown in  FIG. 4 , the peripheral panel  62  includes a front panel portion  63  that is located in front of the void spaces  20   e  and an outer peripheral region  64  that extends rearward and butts against the outer peripheral region  24  of the outer panel  21 . As described above, the reinforcing ribs  59  extending from the outer panel  21  are welded to the front panel portion  63 . 
     As shown in  FIGS. 4 and 9 , the cover panel  66  includes a flat main body  66   a  located in front of the airbag apparatus S and flanges  66   b  that extend rearward from the outer peripheral edge of the main body  66   a . The flanges  66   b  are fitted into fitting portions  63   a  of the front panel portion  63  of the peripheral panel  62 , which are formed along inner peripheral edges of the front panel portion  63 , and are further coupled to the front panel portion  63  by suitable adhesive or fastening structure. The cover panel  66  and peripheral panel  62  are so coupled together as to make the front face  20   c  of the glove box door  20  flush. 
     Referring to  FIGS. 4 to 6 , the airbag apparatus S includes an airbag  71  that protrudes from the outer panel  21  for deployment, an inflator  73  that supplies the airbag  71  with inflation gas and a case  86  that houses the airbag  71  and inflator  73  and is provided at the rear side with an opening  86   a  that allows emergence of the airbag  71 . The airbag apparatus S further includes a holder  33  that connects the case  86  to the outer panel  21 , a pair of mounting elements  55  that assist the mounting of the case  86  to the outer panel  21  and a door  100  that closes off the opening  86   a  of the case  86  and is openable when pushed by the airbag  71  under inflation. The door  100  is comprised of the outer door  27  of the outer panel  21  and holding panel  40  of the holder  33 . 
     The airbag  71 , upon inflation, pushes and opens the door  100  and emerges from the rear face  20   d  of the glove box door  20 , and deploys rearward. The airbag  71  is inflatable into a generally rectangular plate shape elongated in a left and right direction as viewed from the rear, with a certain thickness in an anteroposterior direction as indicated by double-dashed lines in  FIGS. 1 and 3 , thus deployed in front of knees K of an occupant M. 
     Referring to  FIGS. 4 to 6 , the inflator  73  is to feed the airbag  71  with inflation gas. The inflator  73  is generally columnar in shape and is so arranged inside the airbag  71  that its axis extends along a left and right direction. In this specific embodiment, the inflator  73  includes a generally columnar body  74  and a retainer  78  that secures the body  74  to the case  86 . The body  74  includes a generally columnar large-diameter portion  75  and a generally columnar small-diameter portion  76  located at the leading end of the large-diameter portion  75 . The small-diameter portion  76  is provided with a plurality of gas discharge ports  76   a  that emit inflation gas when the inflator  73  is activated. The large-diameter portion  75  is provided on the end facing away from the small-diameter portion  76  with an unillustrated terminal to which a connector C of a lead wire R extending from a predetermined circuit is connected. 
     Referring to  FIGS. 5 and 6 , the retainer  78  includes a base  79  that has a generally rectangular plate shape elongated in a left and right direction, an annular belt portion  80  and a generally hexagonal cylindrical portion  81 . The base  79  includes a plurality of bolts  82 . In this embodiment, the bolts  82  are located on three positions; proximate left and right ends of and at the center in a left and right direction of the base  79 . The cylindrical portion  81  is located proximate the center in a left and right direction of the base  79  in such a manner as to encircle the small-diameter portion  76  of the inflator body  74 . The belt portion  80  is located proximate the right end of the base  79 . 
     As shown in  FIG. 5 , if the bolt  82  located proximate the belt portion  80  is fastened into a nut  84  on a later-described holding area  96   a  of the case  86  while having the outer circumference  75   a  of the front upper region of the root region of the large-diameter portion  75  away from the small-diameter portion  76  abutted on the inner circumference  91   b  of the insert hole  91   a  of the case  86 , the inner circumference of the belt portion  80  pushes the outer circumference  75   b  of the rear lower portion of the large-diameter portion  75  upward and forward and the outer circumference  75   c  of the front upper portion of the leading end region of the large-diameter portion  75  abuts on and is supported by the base  79  and the head  82   a  of the bolt  82 . Thus the retainer  78  secures the inflator body  74  to the case  86  in a stable manner. 
     The case  86  that houses the airbag  71  and inflator  73  is made of sheet metal and is mounted to the holder  33  as best shown in  FIG. 4 . The case  86  includes a generally square tubular circumferential wall  87 , a front wall  96  that closes off the front side of the circumferential wall  87  and the opening  86   a , at the rear side, which allows emergence of the airbag  71 , and thus having a generally rectangular parallelepiped box shape. 
     As shown in  FIGS. 5 and 6 , the circumferential wall  87  includes an upper wall  88  extending rearward from the upper edge of the front wall  96 , a lower wall  89  extending rearward from the lower edge of the front wall  96  so as to oppose the upper wall  88 , a left side wall  90  and right side wall  91  extending rearward in parallel to each other from left and right edges of the front wall  96 . 
     Referring to  FIGS. 4 and 6 , the front wall  96  extends generally vertically when mounted on the globe box door  20  and includes a holding area  96   a  to which the inflator  73  and airbag  71  are secured. The holding area  96   a  includes mounting holes  96   b  for receiving the bolts  82  of the retainer  78  of the inflator  73  to be nut  84  fastened. 
     As best shown in  FIG. 6 , each of the upper wall  88  and lower wall  89  of the circumferential wall  87  is provided with a plurality of hooks  88   a / 89   a  inserted into retaining holes  35   a / 36   a  of later-described upper wall  35 /lower wall  36  of the holder  33  and retaining peripheries of the retaining holes  35   a / 36   a . Each of the hooks  88   a  and  89   a  extends outwardly in a vertical direction from the rear ends of the upper wall  88  and lower wall  89  and then extends forward, thus having a J-shaped section as shown in  FIG. 4 . The hooks  88   a  and  89   a  hold the upper wall  35  and lower wall  36  of the holder  33  securely to help enable the tearable portion  26  and later-described tearable portion  43  of the holder  33  to tear smoothly when the door  100  comprised of the outer door  27  and holding panel  40  is pushed by the airbag  71  upon airbag deployment. 
     As shown in  FIG. 6 , the side walls  90  and  91  of the circumferential wall  87  respectively includes at the rear end a mounting tongue  93  extending outwardly for securing the case  86  to the mounting element  55 . Each of the tongues  93  is provided with two mounting holes  94  for receiving fixing means or bolts  98  from the front side, which bolts are further inserted through screw holes  56  of the mounting element  55  and fasten the tongue  93  to the mounting element  55 . 
     The right side wall  91  further includes a though hole  91   c  for receiving the root-side end  75   d  of the inflator body  74  such that the root-side end  75   d  projects from the case  86  for connection with the above-described connector C for activation of the airbag. 
     The airbag  71 , inflator  73  and the case  86  are preliminarily assembled into an airbag assembly SA for mounting on the holder  33 . The assembling is conducted as follows: The retainer  78  of the inflator  73  is stored inside the airbag  71  such that the bolts  82  project out of the airbag  71 . Then the airbag  71  is folded up. When folded up, the airbag  71  is wrapped up by a wrapping member for keeping the folded-up configuration. Subsequently, inserting the bolts  82  into the mounting holes  96   b  of the holding area  96   a  of the case  86 , the folded-up airbag  71  is housed in the case  86 . Subsequently, the inflator body  74  is set in from the insert hole  91   a  of the case  86  so as to run through the belt portion  80  and cylindrical portion  81  of the retainer  78  housed inside the airbag  71 , and then the bolts  82  are fastened into nuts  84 . Thus the airbag assembly SA is completed. 
     The holder  33  is fabricated of soft synthetic resin which is more flexible than the outer panel  21 . In other words, the outer panel  21  is fabricated of hard synthetic resin which is rigider than the holder  33 . In this specific embodiment, the later-described holding panel  40  and joint flange  46  of the holder  33  are vibration-welded to the outer door  27  and peripheral region  23   a  of the outer panel  21 , and accordingly, the holder  33  is fabricated of thermo-plastic elastomer of olefin which is homogenous to the outer panel  21  of polypropylene so the welding is done easily. 
     As shown in  FIGS. 4 and 7  to  9 , the holder  33  includes a circumferential wall  34 , a holding panel  40 , a joint flange  46 , and a pair of mounting beds  47 . The circumferential wall  34  is formed into a generally square cylindrical shape extending in a generally anteroposterior direction and encircling the case  86  on above, below, left and right. The circumferential wall  34  includes an upper wall  35  and lower wall  36  opposing each other in a vertical direction and a left side wall  37  and right side wall  38  opposing each other in a left and right direction. In this embodiment, the upper wall  35 , lower wall  36 , left side wall  37  and right side wall  38  are coupled to one another into a cylinder. 
     The upper wall  35  and lower wall  36  are respectively provided with a plurality of retaining holes  35   a / 36   a  arranged along a left and right direction for engagement with the hooks  88   a / 89   a  of the upper wall  88 /lower wall  89  of the case  86 . 
     The left side wall  37  and right side wall  38  are respectively provided with a recess  37   a / 38   a  which recesses from the front end. The recesses  37   a  and  38   a  allow the mounting tongues  93  extending from the left side wall  90  and right side wall  91  of the case  86  and the end region  75   d  of the inflator  73  to protrude from the circumferential wall  34 . 
     The joint flange  46  extends outwardly from rear ends of the upper wall  35 , lower wall  36 , left side wall  37  and right side wall  38  of the circumferential wall  34  and vibration-welded to the fore face of a generally square annular area of the rear panel portion  23  encircling the tearable portion  26  of the outer panel  21 , i.e. the peripheral region  23   a.    
     The holding panel  40  includes an upper section  41  and a lower section  42  each having a rectangular plate shape alike the upper flap  28  and lower flap  29  of the outer door  27 . The upper section  41  and lower section  42  are configured openeable. Specifically, the upper section  41  is provided on the top with a U-curved portion which is continuous with the upper wall  35  of the circumferential wall  34  and acts as a hinge  44  when opening upward. The lower section  42  is located below the upper section  41  and is provided at the bottom with a U-curved portion which is continuous with the lower wall  36  and acts as a hinge  44  when opening downward. Between the lower end of the upper section  41  and the upper end of the lower section  42  is a thinned or weakened tearable portion  43  which is tearable when pushed by the airbag  71  under inflation. The tearable portion  43  is formed into a straight line when viewed from the rear. As shown in  FIGS. 7 and 9 , laterals of the upper section  41  and lower section  42  are separated from the left side wall  37  and right side wall  38  of the circumferential wall  34  of the holder  33 . The upper section  41  and lower section  42  may be separated in advance instead of providing the tearable portion  43 . 
     The upper section  41  and lower section  42  are respectively coupled to the fore faces of the upper flap  28  and lower flap  29  of the outer door  27  by vibration welding. When the upper section  41  and lower section  42  open upward and downward about the hinges  44  upon airbag deployment, the upper flap  28  and lower flap  29  break away from the peripheral region  23   a  of the rear panel portion  23  due to the tear of the tearable portion  26 . However, since the upper section  41  and lower section  42  are coupled to and hold the flaps  28  and  29 , and the upper wall  35  and lower wall  36  of the circumferential wall  34  of the holder  33  indirectly hold the flaps  28  and  29  via the hinges  44 , the flaps  28  and  29  are prevented from being blown off. 
     The mounting beds  47  are located on the outside of the left side wall  37  and right side wall  38  of the circumferential wall  34  of the holder  33 . More specifically, the mounting beds  47  are respectively formed on an area extending from the rear side of the recesses  37   a / 38   a  to the joint flange  46 . As described later, the mounting elements  55  are assembled with the mounting beds  47  and the mounting beds  47  hold the mounting elements  55  from moving forward or backward. 
     Mounting elements  55  are provided to assist mounting of the case  86  to the holder  33  and are formed into a plate, respectively, in this specific embodiment. Each of the mounting elements  55  includes a plate  57  formed of a sheet metal having a rectangular shape, two screw holes  56  formed along the length direction of the plate  57  and two nuts  58  welded to peripheries of the screw holes  56 . The mounting element  55  as mounted on board is so arranged that the plate  57  extends vertically and the screw holes  56  are arranged one above the other and have their axial directions extending in an anteroposterior direction. The above-described mounting tongues  93  of the case  86  are secured to the mounting element  55 . 
     As shown in  FIGS. 7 to 9 , each of the mounting beds  47  includes a front regulating region  48  that abuts against the fore face  55   a  of the mounting element  55  and prevents forward movement of the mounting element  55  and a rear regulating region  53  that abuts against the back face  55   b  of the mounting element  55  and prevents backward movement of the mounting element  55 . Each of the mounting elements  55  is set into a slot  47   a  provided between the front regulating region  48  and rear regulating region  53  of each of the mounting beds  47 , and thus mounted to the holder  33 . 
     In this embodiment, the front regulating region  48  has a section shaped like a generally “U” lying on its side as shown in  FIGS. 7 and 8 , and has a front wall  49  and two support walls  51 . Two rear regulating regions  53  are provided to support the rear face  55   b  of the mounting element  55  by the front faces or front ends  53   a  in the vicinity of the screw holes  56 . Each of the rear regulating regions  53  is formed into a rectangular plate shape extending generally along a horizontal direction. Inner ends  53   b  ( FIG. 9 ) of the rear regulating regions  53  facing toward the circumferential wall  34  of the holder  33  are entirely coupled to the left side wall  37  or right side wall  38  of the circumferential wall  34  whereas rear ends  53   c  ( FIG. 8 ) are entirely coupled to the joint flange  46 . 
     The front wall  49  of the front regulating region  48  is formed into a rectangular plate shape extending vertically for abutment against the fore face  55   a  of the mounting element  55  on the rear face  49   b  to prevent the mounting element  55  from moving forward. The inner end  49   c  of the front wall  49  facing toward the circumferential wall  34  of the holder  33  is coupled to the left side wall  37  or right side wall  38  of the circumferential wall  34 . Each of the support walls  51  is formed into a rectangular plate shape extending rearward from the upper/lower end  49   d / 49   e  of the front wall  49 . Inner ends  51   a  ( FIG. 7 ) of the support walls  51  facing toward the circumferential wall  34  are coupled to the left side wall  37  or right side wall  38  of the circumferential wall  34  whereas rear ends  51   b  ( FIG. 8 ) are coupled to the joint flange  46 . 
     In this embodiment, the rear regulating regions  53  are located between the support walls  51 , such that a space defined by the support walls  51 , the fore faces  53   a  of the rear regulating regions  53  and the rear face  49   b  of the front wall  49  acts as the insert slot  47   a  for receiving the mounting element  55 . That is, referring to  FIG. 7 , the dimension HW in an anteroposterior direction of the insert slot  47   a  is generally equal to (slightly smaller than) the thickness t of the plate  57  of the mounting element  55 , and the vertical dimension VW is generally equal to the vertical dimension L of the plate  57 . Thus, when inserted into the slots  47   a  from sides of the left or right side wall  37 / 38  of the circumferential wall  34 , the mounting elements  55  are positioned, prevented from movement in an anteroposterior direction. 
     The front wall  49  of each of the front regulating regions  48  includes on locations corresponding to the screw holes  56  of the mounting element  55  through holes  50 , round in shape, for receiving the bolts  98  acting as fixing means. Needless to add, the through holes  50  and screw holes  56  of the mounting element  55  are formed on locations corresponding to the mounting holes  94  of each of the mounting tongues  93  of the case  86 . 
     Moreover, as shown in  FIG. 4 , a skin layer  31  of woven fabric, nonwoven fabric or the like is adhered to the rear face of the outer panel  21  so as to appear on the rear face  20   d  of the glove box door  20 . The skin layer  31  is tearable when the outer door  27  opens. A skin layer  68  of woven fabric, nonwoven fabric or the like is adhered to the fore face of the inner panel  61 , i.e. fore faces of the cover panel  66  and peripheral panel  62 , so as to appear on the fore face  20   c  of the glove box door  20 . 
     Manufacturing of the glove box door  20  is started by providing the outer panel  21  having the reinforcing ribs  59 , the holder  33 , the peripheral panel  62  and cover panel  66  of the inner panel  61 , the mounting elements  55  and the airbag assembly SA. Then the outer panel  21  is subjected to suitable cutting operation by an end mill or the like to form the tearable portion  26 . Thereafter, the holder  33  is coupled to the outer panel  21  by vibration welding. At this time, the upper section  41  and lower section  42  of the holding panel  40  of the holder  33  are respectively welded to the upper flap  28  and lower flap  29  of the outer door  27  whereas the joint flange  46  is welded to the peripheral region  23   a  of the rear panel portion  23 . The welding strength is so determined that welded regions may not be separated when the door  100  is pushed by the airbag  71  at deployment. 
     Each of the mounting elements  55  is inserted into the slot  47   a  and assembled with the mounting bed  47 . The mounting elements  55  may be attached to the mounting beds  47  before mounting the holder  33  on the outer panel  21 . 
     Subsequently, the outer panel  21  is coupled to the peripheral panel  62  of the inner panel  61  by vibration-welding the front ends  59   a  of the reinforcing ribs  59  to the peripheral panel  62 . 
     Then the airbag assembly SA is set inside the circumferential wall  34  of the holder  33  such that the hooks  88   a  and  89   a  of the case  86  are inserted into the retaining holes  35   a  and  36   a  of the upper wall  35  and lower wall  36  of the circumferential wall  34  and engage with peripheries thereof whereas the mounting tongues  93  of the case  86  abut on the fore faces  49   a  of the front walls  49  of the left and right mounting beds  47 . The bolts  98  are then fastened into the screw holes  56  of the mounting elements  55  via the mounting holes  94  and through holes  50 , thus securing the tongues  93  to the mounting elements  55  attached to the holder  33 . Thus the airbag apparatus S is mounted on the outer panel  21 . 
     Thereafter, the cover panel  66  is so assembled with the peripheral panel  62  of the inner panel  61  as to cover the airbag apparatus S by fitting the flanges  66   b  into the fitting portions  63   a  of the front panel portion  63  of the peripheral panel  62 , and the surface skins  31  and  68  are adhered to the outer circumference, thereby completing the glove box door  20  provided with the airbag apparatus S. The surface skin  31  may alternatively be applied on the outer panel  21  before the welding of the outer panel  21  and peripheral panel  62  of the inner panel  61 , or after the welding and before the assembling of the cover panel  66  with the peripheral region  26 . 
     The glove box door  20  thus manufactured is assembled with the box body  14  to complete the glove box  13 . The glove box  13  is then mounted on a vehicle whereas the lead wire R extending from the activating circuit is connected to the inflator body  74  via not-shown apertures formed on the box body  14  and inner panel  61 . Thus the glove box  13  is installed on the vehicle together with the airbag apparatus S. 
     If an actuating signal is fed to the inflator body  74  via the lead wire R, the inflator  73  discharges inflation gas from the gas discharge ports  76   a . Then the airbag  71  inflates and pushes the door  100  which is comprised of the outer door  27  (upper flap  28  and lower flap  29 ) of the outer panel  21  and the holding panel  40  (upper section  41  and lower section  42 ) of the holder  33 , breaks the tearable portion  26  formed around the outer door  27  of the outer panel  21  and opens the upper region  101  and lower region  102  of the door  100  upward and downward about the hinges  44 . 
     Then the airbag  71  emerges from the emergence opening  86   a  of the case  86 , protrudes rearward from the outer panel  21  and deploys in front of knees K of an occupant M as shown in  FIG. 3 . The deployed airbag  71  properly cushions and protects the knees K moving forward. 
     At this time, the airbag  71  emerged from the glove box door  20  stably receives the knees K without moving since the hinge pins  17 , latches, rear end faces  14   b  ( FIGS. 2 and 3 ) of the box body  14  position the glove box door  20  relative to the box body  14  and prevents it from moving in anteroposterior, lateral and vertical directions. 
     As shown in  FIGS. 1 and 2 , an airbag apparatus  8  for a front passenger&#39;s seat is installed above the glove box  13  for protecting an upper body of the occupant M. The airbag apparatus  8  is mounted on an interior of the top face of the instrument panel  4  and includes an airbag  8   a , an inflator  8   b  for feeding inflation gas to the airbag  8   a , a case  8   c  encasing the airbag  8   a  and inflator  8   b , and an airbag cover  8   d  covering the top of the case  8   c  and provided with a door  8   e  for opening when pushed by the airbag  8   a  under inflation. The airbag cover  8   d  in the illustrated embodiment is integral with the instrument panel  4 . The airbag apparatus  8  is bolt  9  fixed to a bracket  2   a  secured to an instrument panel reinforcement  2 , which is part of the vehicle body structure  1 , by a bracket  8   f  extending from the case  8   c . The airbag apparatus  8  is actuated simultaneously with the knee-protecting airbag apparatus S and the airbag  8   a  pushes and opens the airbag cover  8   d  and deploys to protect the upper body of the occupant M seated in the front passenger&#39;s seat. 
     When the airbag apparatus S mounted on the glove box door  20  is activated, the airbag  71  under inflation pushes the outer door  27  and holding panel  40  of the door  100  rearward, away from the case  86 . On the contrary, the case  86  is subjected to a reaction force of the airbag  71 , which acts forward. However, the mounting tongues  93  of the case  86  extending toward the left and right from opposite sides of the circumferential wall  87  are secured to the mounting elements  55  that are assembled with the holder  33  and prevented from moving forward or backward by the holder  33 . Accordingly, the case  86  is prevented from moving forward by the holder  33 . Moreover, the area of the outer panel  21  encircling the outer circumference of the tearable portion  26 , i.e. the peripheral region  23   a , is prevented from moving backward since the joint flange  46  of the holder  33  is joined to the fore face of the peripheral region  23   a . That is, it is prevented that the peripheral region  23   a  of the outer panel  21  and mounting tongues  93  of the case  86  move away from each other in an anteroposterior direction. With this configuration, if pushed by the airbag  71 , the outer door  27  of the outer panel  21  smoothly break away from the peripheral region  23   a  due to tear of the tearable portion  26 , and opens around the hinges  44  of the holder  33  together with the holding panel  40 . 
     As a result, the airbag  71  smoothly emerges from an opening  25  ( FIG. 4 ) provided by the opening of the door  100  and deploys rearward without being adversely affected by the outer panel  21 . 
     The case  86  is secured to the holder  33  and the holder  33  is coupled to the outer panel  21  by the joint flange  46 . That is, the case  86  is mounted on the outer panel  21  through intermediary of the holder  33 , but is not directly mounted to the inner panel  61 . Accordingly, even when subjected to a forward force upon airbag deployment, the case  86  will not so act as to disconnect the inner panel  61  from the outer panel  21 . Furthermore, the outer panel  21  is fabricated of rigid synthetic resin such as filler-reinforced polypropylene, which has higher rigidity than the holder  33  that is formed of thermo-plastic elastomer of olefin in view of flexibility of the hinges  44 , and therefore, the outer panel  21  holds the case  86  through intermediary of the holder  33  in a stable manner. 
     Further, after airbag deployment, although the inertia force of the airbag  71  pulls the case  86  to the rear, the mounting elements  55  to which the mounting tongues  93  of the case  86  are secured are prevented from moving rearward by the rear regulating regions  53 , and are secured to the rigid outer panel  21  by intermediary of the holder  33 . Thus the case  86  is stably held by the outer panel  21  as well after deployment of the airbag  71 . 
     Moreover, a plurality of the reinforcing ribs  59  are provided between and connect the outer panel  21  and inner panel  61  around the airbag apparatus S in such a manner as to form a plurality of void spaces  20   e  between the panels  21  and  61 . The void spaces  20   e  conduce to lighten the weight of the glove box door  20  and the ribs  59  improve flexural and torsional rigidity of the door  20 . 
     Therefore, the glove box door  20  is rigid and light in weight although having the airbag apparatus S, and deploys the airbag  71  in a smooth fashion. 
     The upper wall  35  and lower wall  36  of the circumferential wall  34  of the holder  33  are retained by the hooks  88   a  and  89   a  of the case  86  and therefore held from moving to the rear. This configuration further assures smooth tear of the tearable portion  26  of the outer door  27  and tearable portion  43  of the holding panel  40  upon airbag deployment because the tearable portions  26  and  43  are prevented from rearward movement. 
     In the glove box door  20  of the foregoing embodiment, moreover, each of the mounting elements  55  is formed into a generally plate shape. The holder  33  includes a pair of mounting beds  47  each of which includes the front regulating region  48  that regulates movement of the mounting element  55  on the front side and the rear regulating region  53  that regulates movement of the mounting element  55  on the rear side. Each of the mounting elements  55  is inserted into the slot  47   a  formed between the front regulating region  48  and rear regulating region  53  and thus attached to the holder  33 . 
     That is, each of the mounting elements  55  is easily assembled with the holder  33  only by insertion into the slot  47   a  formed between the front regulating region  48  and rear regulating region  53  of the corresponding mounting bed  47 . The mounting elements  55  assembled with the holder  33  are clamped by the front regulating regions  48  and rear regulating regions  53  and prevented from forward or rearward movement. Thus the mounting tongues  93  of the case  86  are secured to the mounting elements  55  in a stable manner. 
     Without considering this advantage, it will also be appreciated to mold the holder  33  and mounting elements  55  together by insert molding using the mounting elements  55  as inserts. 
     Moreover, the front regulating region  48  of each of the mounting beds  47  includes the front wall  49  that is connected to the circumferential wall  34  of the holder  33  and regulates movement of the mounting element  55  on the front side and a pair of support walls  51  that extend from upper end  49   d  and lower end  49   e  of the front wall  49  toward the joint flange  46  and coupled to the joint flange  46  while being connected to the circumferential wall  34  of the holder  33 . The front regulating region  48  thus has a U-shaped section. Each of the mounting elements  55  includes the screw holes  56  for receiving the bolts  98  acting as fixing means whereas the front wall  49  of each of the mounting beds  47  includes round through holes  50  for receiving the bolts  98 . The rear regulating region  53  of each of the mounting beds  47  are coupled to the circumferential wall  34  and joint flange  46  and supports vicinities of the screw holes  56  of the mounting element  55  at more than one positions (at two positions, in the illustrated embodiment) from the rear. 
     That is, both of the front regulating region  48  and rear regulating region  53  of each of the mounting beds  47  are coupled to both of the joint flange  46  and circumferential wall  34 . The joint flange  46  extends vertically along the tearable portion  26  of the outer panel  21 . The circumferential wall  34  has a cylindrical shape extending in an anteroposterior direction and surrounding the case  86 . Coupled to these two parts of the holder  33  extending mutually orthogonally, the front regulating region  48  and rear regulating region  53  are enhanced in rigidity. Clamped by these front regulating region  48  and rear regulating region  53 , the mounting elements  55  are positioned in a further stable fashion. Moreover, the front wall  49  of the front regulating region  48  is prevented from moving forward, i.e. moving away from the outer panel  21 , by the support walls  51  coupled to the circumferential wall  46  and joint flange  46  at opposite ends (upper end  49   d  and lower end  49   e ) while abutting against the entire fore face  55   a  of the mounting element  55 . Therefore the front wall  49  securely prevents the mounting element  55  from moving forward. In addition, the rear regulating regions  53  are coupled to the circumferential wall  34  and joint flange  46  and support vicinities of the screw holes  56  of the mounting element  55  at two positions from the rear. Therefore the rear regulating regions  53  securely prevent the mounting element  55  from moving rearward. 
     The inner panel  61  includes the cover panel  66  that is fabricated of synthetic resin and located in front of the airbag apparatus S and the peripheral panel  62  that is fabricated of synthetic resin as well and located around the cover panel  66 . The reinforcing ribs  59  are integral with the outer panel  21  and welded to the peripheral panel  62 , thus connecting the outer panel  21  and peripheral panel  62 . 
     That is, the outer panel  21  and inner panel  61  are easily coupled together by welding the reinforcing ribs  59  extending from the outer panel  21  to the peripheral panel  62  of the inner panel  61 . Additionally, this configuration provides firm connection between the reinforcing ribs  59 , outer panel  21  and inner panel  61 , thus preventing the inner panel  61  from moving away from the outer panel  21  and enhancing rigidity of the glove box door  20 . Although the outer panel  21  and inner panel  61  are welded together by vibration-welding of the reinforcing ribs  59 , the welded portions will stay intact upon airbag deployment since the inner panel  61  is not subjected to forward pressing force of the case  86  as described above. 
     Although the reinforcing ribs  59  in the foregoing embodiment are formed integrally with the outer panel  21 , the reinforcing ribs  59  may be formed to extend rearward from the front panel portion  63  of the peripheral panel  62  of the inner panel  61  and welded to the outer panel  21  by vibration-welding. 
     Although the inner panel  61  of the foregoing embodiment is comprised of two split parts; the peripheral panel  62  and cover panel  66 , it may be formed of a single plate-shaped material as shown in  FIG. 10 . A glove box door  20 A depicted in  FIG. 10  has a similar structure to the glove box door  20  of the foregoing embodiment except in that an inner panel  61 A is formed of a single plate-shaped material and coupled to the holder  33 A and outer panel  21 A by clip connection, adhesive and so on. The inner panel  61 A includes a first engaging portion  105  having a flexible hook-like shape for engagement with a second engaging portion (engaging hole)  104  formed on the outer panel  21 A and holder  33 A. The inner panel  61 A and outer panel  21 A or holder  33 A are coupled together by suitable adhesive in addition to engagement of the first engaging portion  105  and second engaging portion  104 . The assembling of the inner panel  61 A with the outer panel  21 A and holder  33 A is conducted after the installing of the airbag apparatus S on the holder  33 A. 
     This configuration that the inner panel  61 A is formed of a single plate-shaped material facilitates manufacturing of the glove box door  20 A compared to the configuration of the foregoing embodiment in which the inner panel  61  is comprised of two split parts because it does not require a step for coupling the split parts. 
     In the glove box door  20 / 20 A of the foregoing embodiments, the outer panel  21 / 21 A includes the reinforcing ribs  59  integral with the outer panel  21 / 21 A at least proximate the holder  33 / 33 A. This configuration conduces to enhance rigidity of the outer panel  21  in the vicinity of the holder  33 / 33 A, and thus assuring steady operation of the airbag apparatus S. 
     Although the mounting tongues  93  of the case  86  of the foregoing embodiments are formed on the left and right side walls  90  and  91 , the mounting tongues  93  may alternatively be formed on the upper wall  88  and lower wall  89 . It will also be appreciated to form one additional mounting tongue on the upper wall or lower wall in addition to those on the left and right side wall or form one additional on the left or right side wall in addition to those on the upper and lower walls. Further alternatively, mounting tongues  93  may be formed on four sides around the opening  86   a  of the case  86  for coupling with correspondingly-formed mounting elements  55  and mounting beds  47 . 
     Although the door  100  opening to allow airbag emergence has been described as a double door that opens upward and downward, the door may be a single door that opens upward or downward.