BACKGROUND 
   The present invention relates to an airbag and, more specifically, to an airbag apparatus. A conventional airbag apparatus, which is disclosed in Japanese Unexamined Patent Application Publication No. 2002-178868, includes an inflator that inflates an airbag by injecting pressurized fluid into the airbag, upon detection of an impact associated with collision of a vehicle. Such an airbag apparatus includes: (a) a column-shaped inflator for injecting pressurized fluid; (b) a retainer for supporting the bottom side of the inflator; and (c) an airbag plate, which is located on the upper side of the inflator and which clamps an opening edge of the airbag body, when engaged with the retainer. One end of a bracket is fixed to the retainer whereas the other end of the bracket is fixed to a vehicle body, whereby the entire airbag apparatus is fixed to the vehicle body. 
   In the aforementioned airbag apparatus, although both ends of the bottom side of the inflator are supported by the retainer, both ends of the upper side of the inflator are unsupported. As a result, the positioning of the airbag plate with respect to the inflator in the thrust direction is unstable and, therefore, a rattle may be generated due to vibrations during vehicle travel. 
   Accordingly, the present invention has been made in light of the aforementioned problems. An object of the present invention is to provide an airbag apparatus in which the positioning of the airbag plate with respect to the inflator in the thrust direction is stable, so as to reduce or inhibit the generation of a rattle that may otherwise be caused by vibrations associated with vehicle travel. 
   SUMMARY 
   An embodiment of the invention addresses an airbag apparatus that includes, among other possible things: a retainer that is configured to support a bottom side of an inflator; and an airbag plate that is configured to be connected to the retainer. The inflator has two ends and is configured to inject pressurized fluid into an airbag body. The airbag plate is configured to be positioned on an upper side of the inflator. When the retainer and the airbag plate are connected, the airbag plate and the retainer are configured to clamp an edge of a bottom opening of the airbag body. The airbag plate is formed with shoulders that are configured to abut both ends of the inflator, to inhibit the formation of vibrations associated with the inflator. 
   In a further embodiment of this airbag apparatus, each of the shoulders may have a substantially tapered-shape. 
   In another further embodiment of this airbag apparatus, the shoulders may be integrally formed with the airbag plate. 
   In another further embodiment of this airbag apparatus, the apparatus may additionally include tongue strips that formed on the airbag plate. Moreover, each of the tongue strips may be shaped like an arrow tip. Additionally, each of the tongue strips may penetrate the airbag body proximate the bottom opening. 
   Another embodiment of the invention addresses an airbag apparatus that includes, among other possible things: a retainer that is configured to support a bottom side of an inflator; and an airbag plate that is configured to be connected to the retainer. The inflator has two ends and is configured to inject pressurized fluid into an airbag body. The airbag plate is configured to be positioned on an upper side of the inflator. When the retainer and the airbag plate are connected, the airbag plate and the retainer are configured to clamp an edge of a bottom opening of the airbag body. The airbag plate is formed with tongue strips that are configured to abut both ends of the inflator, to inhibit the formation of vibrations associated with the inflator. 
   In a further embodiment of this airbag apparatus, each of the tongue strips may be shaped like an arrow tip. Additionally, in a further embodiment of this airbag apparatus, each of the tongue strips may penetrate the airbag body proximate the bottom opening. 
   In a further embodiment of this airbag apparatus, the tongue strips may be integrally formed with the airbag plate. 
   In the aforementioned airbag apparatus embodiments, the positioning between the airbag plate and the inflator in the thrust direction can be achieved without providing an additional fixture by means of which the inflator could otherwise be stabilized. 
   It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only, and are not restrictive of the invention as claimed. 


   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     These and other features, aspects, and advantages of the present invention will become apparent from the following description, appended claims, and the accompanying exemplary embodiments shown in the drawings, which are briefly described below. 
       FIG. 1  is a cross-sectional view of a first embodiment of an airbag apparatus according to the present invention; 
       FIG. 2  is a perspective view of an airbag plate that is part of the airbag apparatus of the embodiment shown in  FIG. 1 ; 
       FIG. 3  is a side view of the airbag plate shown in  FIG. 2 ; 
       FIG. 4A  is a perspective view of the airbag body of the embodiment shown in  FIG. 1 ; 
       FIG. 4B  is a bottom view of a portion of the airbag body shown in  FIG. 4A ; 
       FIG. 5A  is a side view of the airbag apparatus of the embodiment shown in  FIG. 1 ; 
       FIG. 5B  is a front view of the airbag apparatus of the embodiment shown in  FIG. 1 ; 
       FIG. 6  is a cross-sectional view of a second embodiment of an airbag apparatus according to the present invention; 
       FIG. 7  is a perspective view of an airbag plate that is part of the airbag apparatus of the embodiment shown in  FIG. 6 ; 
       FIG. 8A  is a perspective view of an airbag body of the embodiment shown in  FIG. 6 ; 
       FIG. 8B  is a bottom view of a portion of the airbag body shown in  FIG. 8A ; 
       FIG. 9A  is a side view of the airbag apparatus of the embodiment shown in  FIG. 6 ; and 
       FIG. 9B  is a front view of the airbag apparatus of the embodiment shown in  FIG. 6 . 
   


   DETAILED DESCRIPTION 
   Embodiments of the present invention will be described with reference to the drawings. Like numbers are used throughout the drawings to refer to the same or similar parts in each of the embodiments of the invention described herein. A first embodiment of the present invention will be described with respect to  FIGS. 1-5B  and a second embodiment of the present invention will be described with respect to  FIGS. 6-9B . 
   The first airbag apparatus  1  embodiment is shown in  FIG. 1 . The airbag apparatus  1  includes: (a) a retainer  3  that has a plurality of fixing brackets  2  that are configured to engage a vehicle body (not shown); (b) an elongated or column-shaped inflator  4 , a lower side of which is supported by the retainer  3 ; (c) an airbag plate  5  (shown best in  FIGS. 2-3 ) that supports an upper side of the inflator  4 ; and (d) an airbag body  6 , a bottom portion of which is clamped between the retainer  3  and the airbag plate  5 . 
   When the inflator  4  is activated, the inflator  4  injects pressurized fluid into the airbag body  6  via a bottom opening  6   a  thereof, thereby causing the airbag body  6  to inflate into a deployed configuration that is shown in  FIG. 4A . The bottom opening  6   a  is formed by two longitudinal edges and two widthwise edges, as shown in  FIG. 4B . The bottom opening  6   a  is formed with, e.g., five bolt holes  6   b  that are positioned near the longitudinal edges thereof and with slits  6   c  that are positioned near the widthwise edges thereof. 
   As shown in  FIG. 1 , the retainer  3  includes a substantially box-shaped upper retainer  7  and a lower retainer  8  that is connected to the upper retainer  7 . The airbag body  6  is folded and stored in the upper retainer  7 ; the folding and storage of the airbag body  6  is completed so that the airbag body  6  may be inflated and deployed in a predetermined manner. The lower retainer  8  is formed with a depression at the center portion thereof. The depression may be formed, e.g., by punching or the like so as to receive the bottom side of the inflator  4 . A bottom center portion  8   a  of the lower retainer  8  is bent in a semi-hexagonal shape (in cross-section). The lower retainer  8  also includes two side portions  8   b  that are formed into a semi-circular shape. Upper sides of both ends of the lower retainer  8  are formed with elongated holes  8   c  at positions substantially corresponding to the both ends of the inflator  4 . 
   The inflator  4  is a fluid (e.g., gas) generating device that is configured to inflate the airbag body  6 , thereby causing the airbag body  6  to deploy. The inflator  4  itself may be of a conventional type. Moreover, the inflator  4  may be, e.g., of a compressed-gas type, a combustion-gas type, or other suitable inflator. 
   The airbag plate  5  serves to fix the airbag body  6  and the inflator  4  inside the retainer  3 . As is most clearly shown in  FIG. 2 , the airbag plate  5  includes: (a) an arched portion  5   a  that is formed into a semi-circular arch shape; and (b) a flange portion  5   b  that is formed at both longitudinal edges of the arched portion  5   a.    
   A plurality (e.g., four) of openings  5   c  (which may, as shown, be generally square in shape), which are configured to allow gas from the inflator  4  to pass therethrough, are formed at the center of the arched portion  5   a . Tongue strips  5   d , which may be shaped like arrow tips, extend from the left and right outer edges of the arched portion  5   a . The tongue strips  5   d  are configured to penetrate through the slits  6   c  of the bottom opening of the airbag body  6 . 
   Shoulders  5   e  are formed between the arched portion  5   a  and the tongue strips  5   d . As shown, the shoulders  5   e  may have a tapered-shape that upwardly increases in width. Moreover, in some embodiments, the airbag plate  5  and the shoulders  5   e  may be integrally formed. In the assembled state, the shoulders  5   e  are configured to abut both ends of the inflator  4 , which is positioned therebetween. 
   The flange portion  5   b  is provided with a plurality (e.g., five) bolts  5   f . The bolts  5   f  are journalled through the bolt holes  6   b  of the airbag body  6  and through holes (not shown) provided on the lower retainer  8 . As a result, the bolts  5   f , in conjunction with nuts  9 , enable the airbag plate  5  to be fixed to the lower retainer  8 . 
   The airbag apparatus or module  1  according to the first embodiment may be assembled in the manner hereafter described. First, the airbag body  6  is connected to the airbag plate  5  by passing (i) the tongue strips  5   d  through the slits  6   c  from the inner side of the airbag body  6  and (ii) the bolts  5   f  through the through bolt holes  6   b . As a result, the arched portion  5   a  of the airbag plate  5  will be provided in the bottom opening  6   a  of the airbag body  6 . Moreover, by providing an odd number of bolts  5   f  (e.g., five in the shown embodiment) that are not uniformly spaced, an erroneous assembly of the airbag plate  5  and the airbag body  6  may be prevented (or at least greatly inhibited). 
   Second, the airbag plate  5  (and the airbag body  6  that is affixed thereto) is disposed inside the upper retainer  7 , while the inflator  4  is supported by the lower retainer  8 . The tongue strips  5   d  are then pushed through the elongated holes  8   c  and the bolts  5   f  are pushed through the through holes of the lower retainer  8 , respectively. As a result, (a) a peripheral edge of the bottom opening  6   a  of the airbag body  6  is clamped between the airbag plate  5  and the lower retainer  8  and (b) both ends of the inflator  4  are positioned between the shoulders  5   e  of the airbag plate  5 . 
   Third, by tightening the nuts  9  completely onto the bolts  5   f , (a) the airbag body  6  is completely clamped to the airbag plate  5  and the lower retainer  8 , and (b) the inflator  4  is clamped between the lower retainer  8  and the airbag plate  5  (and the shoulders  5   e  thereof). 
   The airbag apparatus  1  may then be fixed in a vehicle body by means of the brackets  2 . For example, when it is used as a passenger airbag module (for protecting, e.g., a passenger&#39;s head, upper body, lower legs, etc.), the airbag apparatus  1  may be fixed in the vehicle&#39;s instrument panel. 
   In the airbag apparatus  1  embodiment previously described, the airbag body  6  may typically be folded and stored in the upper retainer  7 . When the vehicle is involved in a collision, a sensor (not shown) may detect this collision and send an ignition signal to the inflator  4 . In response to the ignition signal, the inflator  4  may inject pressurized fluid into the airbag body  6  via the openings  5   c  of the airbag plate  5  and the bottom opening  6   a  of the airbag body  6 . 
   The second airbag apparatus  11  embodiment is shown in  FIG. 6 . The airbag apparatus  11  includes: (a) a retainer  13  that has a plurality of fixing brackets  12  that are configured to engage a vehicle body (not shown); (b) a column-shaped inflator  14 , a lower side of which is supported by the retainer  13 ; (c) an airbag plate  15  (shown best in  FIG. 7 ) that supports an upper side of the inflator  14 ; and (d) an airbag body  16 , a bottom portion of which is clamped between the retainer  13  and the airbag plate  15 . 
   When the inflator  14  is activated, the inflator  14  injects pressurized fluid into the airbag body  16  via a bottom opening  16   a  thereof, thereby causing the airbag body  16  to inflate into a deployed configuration that is shown in  FIG. 8A . The bottom opening  16   a  is formed by two longitudinal edges and two widthwise edges, as shown in  FIG. 8B . The bottom opening  16   a  is formed with, e.g., five bolt holes  16   b  that are positioned near the longitudinal edges thereof and with slits  16   c  that are positioned near the widthwise edges thereof. 
   As shown in  FIG. 6 , the retainer  13  includes a substantially box-shaped upper retainer  17  and a lower retainer  18  that is connected to the upper retainer  17 . The airbag body  16  is folded and stored in the upper retainer  17 ; the folding and storage of the airbag body  16  is completed so that the airbag body  16  may be inflated and deployed in a predetermined manner. The lower retainer  18  is formed with a depression at a center portion thereof. The depression may be formed, e.g., by punching or the like so as to receive the bottom side of the inflator  14 . A bottom center portion  18   a  of the lower retainer  18  is bent in the semi-hexagonal shape (in cross-section). The lower retainer  18  also includes two side portions  18   b  that are formed into a semi-circular shape. Upper sides of both ends of the lower retainer  18  are formed with elongated holes  18   c  at positions substantially corresponding to the both ends of the inflator  14 . 
   The inflator  14  is a fluid (e.g., gas) generating device that is configured to inflate the airbag body  16 , thereby causing the airbag body  16  to deploy. The inflator  14  itself may be of a conventional type. Moreover, the inflator  14  may be, e.g., of a compressed-gas type, a combustion-gas type, or other suitable inflator. 
   The airbag plate  15  serves to fix the airbag body  16  and the inflator  14  inside the retainer  13 . As is most clearly shown in  FIG. 7 , the airbag plate  15  includes: (a) an arched portion  15   a  that is formed into a semi-circular arch shape; and (b) a flange portion  15   b  that is formed at both longitudinal edges of the arched portion  15   a.    
   A plurality (e.g., four) openings  15   c  (which may, as shown, be generally square in shape), which are configured to allow gas from the inflator  14  to pass therethrough, are formed at the center of the arched portion  15   a . Tongue strips  15   d , which may be shaped like arrow tips, extend from the left and right outer edges of the arched portion  15   a . Moreover, in some embodiments, the airbag plate  15  and the tongue strips  15   d  may be integrally formed. The tongue strips  15   d  are configured to penetrate through the slits  16   c  of the bottom opening  16   a  of the airbag body  16 . In the assembled state, which is later discussed in detail, the tongue strips  11   d  are configured to abut and, therefore, retain both ends of the inflator  14 . 
   The flange portion  15   b  is provided with a plurality (e.g., five) bolts  15   e . The bolts  15   e  are journalled through the bolt holes  16   b  of the airbag body  16  and through holes (not shown) provided on the lower retainer  18 . As a result, the bolts  15   e , in conjunction with nuts  19 , enable the airbag plate  15  to be fixed to the lower retainer  18 . 
   The airbag apparatus  11  according to the second embodiment may be assembled in the manner hereafter described. First, the airbag body  16  is connected to the airbag plate  15  by passing (i) the tongue strips  15   d  through the slits  16   c  from the inner side of the airbag  16  and (ii) the bolts  15   e  through the through bolt holes  16   b . As a result, the arched portion  15   a  of the airbag plate  15  will be provided in the bottom opening  16   a  of the airbag body  16 . Moreover, by providing an odd number of bolts  15   e  (e.g., five in the shown embodiment) that are not uniformly spaced, an erroneous assembly of the airbag plate  15  and the airbag body  16  may be prevented (or at least greatly inhibited). 
   Second, the airbag plate  15  (and the airbag body  16  that is affixed thereto) is disposed inside the upper retainer  17 , while the inflator  14  is supported by the lower retainer  18 . The tongue strips  15   d  are then pushed through the elongated holes  18   c  and the bolts  15   e  are pushed through the through holes of the lower retainer  18 , respectively. As a result, (a) a peripheral edge of the bottom opening  16   a  of the airbag body  16  is clamped between the airbag plate  15  and the lower retainer  18  and (b) both ends of the inflator  14  are positioned between the tongue strips  15   d.    
   Third, by tightening the nuts  19  completely onto the bolts  15   e , the airbag body  16  is completely clamped to the airbag plate  15  and the lower retainer  18 , and (b) the inflator  14  is clamped between the lower retainer  18  and the airbag plate  15  (and the tongue strips  15   d  thereof). 
   The airbag apparatus  11  may then be fixed in a vehicle body by means of the brackets  12 . For example, when it is used as a passenger airbag apparatus (for protecting, e.g., a passenger&#39;s head, upper body, lower legs, etc.), the airbag apparatus  11  may be fixed in the vehicle&#39;s instrument panel. 
   In the airbag apparatus  11  embodiment previously described, the airbag body  16  may typically be folded and stored in the upper retainer  17 . When the vehicle is involved in a collision, a sensor (not shown) may detect this collision and send an ignition signal to the inflator  14 . In response to the ignition signal, the inflator  14  may inject pressurized fluid into the airbag body  16  via the openings  15   c  of the airbag plate  15  and the bottom opening  16   a  of the airbag body  16 . 
   The priority applications, Japanese Application No. 2004-224131 and Japanese Application No. 2004-224132 (both of which were filed on Jul. 30, 2004) are incorporated herein by reference in their entireties. 
   Given the disclosure of the present invention, one versed in the art would appreciate that there may be other embodiments and modifications within the scope and spirit of the invention. Accordingly, all modifications attainable by one versed in the art from the present disclosure that are within the scope and spirit of the present invention are to be included as further embodiments of the present invention. The scope of the present invention is to be defined as set forth in the following claims.
The positioning of an airbag plate with respect to an inflator is achieved so as to prevent the generation of a rattle that may otherwise be caused by vibrations during vehicle travel. The bottom side of a column-shaped inflator that injects pressurized fluid is supported by a retainer. An opening edge of an airbag body is clamped between an airbag plate and the retainer when the airbag plate, which is located on the upper side of the inflator, is engaged with the retainer. The edge of the bottom opening of the airbag body is clamped between the airbag plate and the inflator. In one embodiment, shoulders, which are provided on the airbag plate, abut both ends of the inflator. In another embodiment, tongue strips, which are provided on the airbag plate, abut both ends of the inflator.