Patent Publication Number: US-7213835-B2

Title: Occupant restraint system

Description:
BACKGROUND OF THE INVENTION 
   1. Field of the Invention 
   The present invention relates to an occupant restraint system in which an air bag in a folded state is arranged in such a manner as to extend along a side portion of a roof and a pillar, so that, when a vehicle is involved in a collision, the air bag is inflated with a gas generated by an inflator so as to be deployed in a curtain-like fashion along an inner surface of a side portion of a passenger compartment. 
   2. Description of the Related Art 
   The occupant restraint system is known by JP-A-9-315253. A front end portion of the air bag of the occupant restrain system is accommodated in a folded state in a space formed between a front pillar (A pillar) and a pillar garnish fixed to a side of the front pillar which faces the passenger compartment with clips. The air bag inflated when the vehicle is involved in a collision is designed to push open the pillar garnish to be deployed into the passenger compartment. 
   Incidentally, clips for fixing the pillar garnish to the front pillar and brackets with which the clips are brought into engagement are disposed in the space where the near-front end portion of the air bag of the related-art occupant restraint system is accommodated, that is, the space formed between the front pillar and the pillar garnish. Therefore, there has been a possibility that the air bag which is being inflated is brought into contact with the clips or brackets to be damaged. 
   SUMMARY OF THE INVENTION 
   The invention was made in view of these situations, and an object thereof is to provide an occupant restraint system which can prevent a damage to an air bag accommodated in a folded state within a pillar garnish that would occur when the air bag which is being inflated interferes with the other members provided within the pillar garnish. 
   With a view to attaining the object, according to a first aspect of the invention, there is proposed an occupant restraint system comprising: 
   an air bag in a folded state being arranged in such a manner as to extend along a side portion of a roof and a pillar, the air bag being inflated with a gas generated by an inflator so as to be deployed in a curtain-like fashion along an inner surface of a side portion of a passenger compartment when a vehicle is involved in a collision; and 
   a pillar garnish mounted on a side of a pillar which faces the passenger compartment, the pillar garnish having a bulkhead for partitioning a space formed between the pillar and the pillar garnish so as to define an air bag accommodation chamber for accommodation of the air bag. 
   According to the construction, since the space formed between the pillar and the pillar garnish is partitioned by the bulkhead provided on the pillar garnish so as to define the air bag accommodation chamber where the air bag is accommodated, the bulkhead is allowed to be interposed between other members residing within the pillar garnish and the air bag so as to ensure the prevention of a damage to the air bag that would be caused when the air bag which is in the process of inflation interferes with the other members. 
   Note that a D pillar  17  in embodiments of the invention corresponds to the pillar of the invention. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG. 1  is a drawing showing an inside of a passenger compartment of a vehicle when an air bag is in a non-deployed state; 
       FIG. 2  is a drawing showing the inside of the passenger compartment of the vehicle when the air bag has been deployed; 
       FIG. 3  is an enlarged view of a main part of  FIG. 2 ; 
       FIG. 4  is an exploded perspective view of an occupant restraint system; 
       FIG. 5  is an enlarged cross-sectional view taken along the line  5 — 5  in  FIG. 1 ; 
       FIG. 6  is an enlarged cross-sectional view taken along the line  6 — 6  in  FIG. 2 ; 
       FIG. 7  is a cross-sectional view of a portion of a D pillar which relates to a second embodiment; and 
       FIG. 8  is a cross-sectional view of a portion of the D pillar which relates to a third embodiment. 
   

   DETAILED DESCRIPTION OF THE INVENTION 
   A mode for carrying out the invention will be described below based on embodiments of the invention which are illustrated in the accompanying drawings. 
     FIGS. 1 to 6  show an embodiment of the invention, in which  FIG. 1  is a drawing showing an inside of a passenger compartment of a vehicle when an air bag is in a non-deployed state,  FIG. 2  is a drawing showing the inside of the passenger compartment of the vehicle when the air bag has been deployed,  FIG. 3  is an enlarged view of a main part of  FIG. 2 ,  FIG. 4  is an exploded perspective view of an occupant restraint system,  FIG. 5  is an enlarged cross-sectional view taken along the line  5 — 5  in  FIG. 1 , and  FIG. 6  is an enlarged cross-sectional view taken along the line  6 — 6  in  FIG. 2 . 
   As shown in  FIG. 1 , a recreational vehicle or RV has a front-row seat  11 , a center-row seat  12  and a rear-row seat  13 . The RV also has A pillars  14 , B pillars  15 , C pillars  16  and D pillars  17 . A front side door  18  is disposed between the A pillar  14  and the B pillar  15 , a rear side door  19  is disposed between the B pillar  15  and the C pillar  16 , and a tailgate  20  is disposed rearward of the D pillar  17 . An air bag  21 , which is folded, of an occupant restraint system C is accommodated so as to extend in a longitudinal direction of a vehicle body along a side portion of a roof  22  defined between the A pillar  14  and the D pillar  17 . Note that while occupant restraint systems C having substantially the same construction are provided on both sides of the vehicle body, an occupant restraint system provided on the right-hand side of the vehicle body will be described below as representing the systems so provided. 
   As is clear from  FIGS. 2 to 4 , the air bag  21  is constructed by sewing  32  . . . a double-layered fabric base  31  and includes front and rear gas distribution passageways  21   a ,  21   b  which extend longitudinally along an upper edge of the air bag  21 . The air bag  21  also includes a plurality of cells  21   c . . .  which are branched to descend from the front gas distribution passageway  21   a  for protecting the head of an occupant on the front-row seat  11 , a plurality of cells  21   d . . .  which are branched to descend from the rear gas distribution passageway  21   b  for protecting the head of an occupant on the center-row seat  12  and a plurality of cells  21   e . . .  which are branched to descend from the rear gas distribution passageway  21   b  for protecting the head of an occupant on the rear-row seat  13 . 
   A non-deployable portion  21   f  to which no gas is supplied is formed ahead of the cells  21   c . . .  for the occupant on the front-row seat  11 , a non-deployable portion  21   g  to which no gas is supplied is formed between the cells  21   c . . .  for the occupant on the front-row seat  11  and the cells  21   d . . .  for the occupant on the center-row seat  12 , and a non-deployable portion  21   h  to which no gas is supplied is formed between the cells  21   d . . .  for the occupant on the center-row seat  12  and the cells  21   e . . .  for the occupant on the rear-row seat  13 . Then, a plurality of attaching portions  21   i . . .  formed along the upper edge of the air bag  21  are fixed to the roof  22 , the A pillar  14  and the D pillar  17 . 
   The folded air bag  21  is encompassed by fabric covers  33 ,  34  which are divided longitudinally. The respective covers  33 ,  34  are sewn along lower edges thereof and are then formed into a cylindrical configuration, and the deployment of the. air bag  21  is made possible when the covers  33 ,  34  break at stitch-like breakable portions  33   a . . . ,    34   a . . .  which are formed along the lengths of the covers  33 ,  34 . The plurality of attaching portions  21   i . . .  formed along the upper edge of the air bag  21  are allowed to protrude upwardly through openings  33   b . . . ,    34   b . . .  which are formed in upper sides of the covers  33 ,  34 . 
   As is clear from  FIGS. 3 and 4 , an inflator  35  is disposed on the side portion of the roof  22  at a position which faces an upper end of the C pillar  16 . A gas supply pipe  36  which extends forward from an end portion of the inflator  35  is bent downwardly and is then branched into a longitudinal fork. A gas injection port  36   a  at a front end of the forked gas supply pipe  36  is inserted into a front gas supply port  21   j  at a rear end of the front gas distribution passageway  21   a  and is then fixed in place with a fixing band  37 . A gas injection port  36   b  at a rear end of the forked gas supply pipe  36  is then inserted into a rear gas supply port  21   k  at a front end of the rear gas distribution passageway  21   b  and is then fixed in place with a fixing band  38 . As this occurs, the fabric base  31  is cut out in a trapezoidal shape to form an opening  21   m  below the front and rear gas supply ports  21   j,    21   k  in order to avoid interferences with the fixing bands  37 ,  38 . The gas supply pipe  36  is fixed to the vehicle body with a fixing member  39  and bolts  40 ,  40 . 
   As is clear from  FIGS. 4 and 5 , the D pillar  17  is constructed to have a closed cross section by welding together three members such as a pillar outer  41 , a pillar inner  42  and a stiffener  43 , and a side of the pillar inner  42  which faces the passenger compartment is covered with a synthetic resin pillar garnish  44 . A plurality of clip mounting seats  44   a  . . . and a bulkhead  44   b  which extends longitudinally are formed integrally on an inner surface of the pillar garnish  44 . The pillar garnish  44  is fixed to the pillar inner  42  by inserting clips  45  . . . supported in the clip mounting seats  44   a  . . . into openings  46   a  in brackets  46  . . . welded to the pillar inner  42  so as to be locked in place therein. Part of a space surrounded by the pillar inner  42  and the pillar garnish  44  is partitioned by the bulkhead  44   b  so as to define an air bag accommodation chamber  47  where the folded air bag  21  is accommodated. 
   Note that a side edge of the tailgate  20  abuts with a weatherstrip  48  mounted on a rear portion of the D pillar  17  and that a rear side glass  49  is bonded to a front side of the D pillar  17 . 
   Next, the function of the embodiment of the invention that is constructed as has been described heretofore will be described below. 
   When a side collision or a roll-over of the vehicle is detected by an acceleration sensor, the inflator  35  is activated by a command from an electronic control unit, and a gas stored under pressure in the inflator  35  is supplied into the longitudinal gas distribution passageways  21   a,    21   b  of the air bag  21  via the gas supply pipe  36  and then flows therefrom into the respective cells  21   c . . . ,    21   d . . . ,    21   e . . .  As a result, the air bag  21  accommodated in the folded state in such a manner as to extend along the side portion of the roof  22  is then inflated, and as shown in  FIG. 6 , while pushing downwardly a roof garnish by virtue of the pressure thereof, the air bag  21  is deployed downwardly into the passenger compartment through an opening formed. The front-end cells  21   c . . .  of the air bag  21  so deployed protect the head of the occupant on the front-row seat  11 , the central cells  21   d . . .  protect the head of the occupant on the center-row seat  12 , and the rear-end cells  21   e . . .  protect the head of the occupant on the rear-row seat  13 . 
   As this occurs, a rear part of the air bag  21  accommodated along the D pillar  17  is inflated within the interior of the air bag accommodation chamber  47  partitioned by the bulkhead  44   b  of the pillar garnish  44  and deploys into the passenger compartment while pushing open an edge portion of the pillar garnish  44  which extends along the rear side glass  49 . The interference of the air bag  21  with the clips  45  and the brackets  46  which are provided adjacent thereto is prevented by allowing the air bag  21  to be inflated within the air bag accommodation chamber  47 , whereby a risk that the air bag  21  is damaged by the interference thereof with the clips  45  and brackets  46  can be prevented. Moreover, the position of the accommodated air bag becomes stable due to the provision of the air bag accommodation chamber  47 , whereby the deployment of the air bag can be ensured. 
   Next, a second embodiment of the invention will be described based on  FIG. 7   
   While the pillar garnish  44  of the first embodiment is formed integrally, a pillar garnish  44  of a second embodiment is divided into two portions; a first portion  44 A and a second portion  44 B by a dividing line P, and a bulkhead  44   b  is formed integrally on the second portion  44 B. 
   Next, a third embodiment of the invention will be described based on  FIG. 8 . 
   While the pillar garnish  44  of the first embodiment is formed integrally, a pillar garnish  44  of a third embodiment is divided into two portions; a first portion  44 A and a second portion  44 B by a dividing line P, and a bulkhead  44   b  is formed integrally on the first portion  44 A. 
   Thus, functions and advantages similar to those attained by the first embodiment can be attained even by the second and third embodiments, and moreover, since the second portion  44 B is allowed to separate from the first portion  44 A easily when the air bag  21  is inflated, the formation of an opening from which the air bag is deployed can be ensured. 
   Thus, while the embodiments of the invention have been described in detail heretofore, the invention can be modified variously with respect to the design thereof without departing from the spirit and scope thereof. 
   For example, while the invention is applied to the D pillar  17  in the embodiments, the invention can be applied to the A pillar  14 . In addition, in a sedan-type vehicle having no D pillar  17 , the invention can be applied to the C pillar  16  which is positioned rearmost. 
   In addition, while the bulkhead  44   b  is formed integrally with the pillar garnish  44  in the embodiments, the bulkhead  44   b  can be constituted by a separate member from the pillar garnish  44 . 
   According to the first aspect of the invention that has been described heretofore, since the space formed between the pillar and the pillar garnish is partitioned by the bulkhead provided on the pillar garnish to define the air bag accommodation chamber for accommodation of the air bag, the bulkhead is allowed to be interposed between the other members residing in the pillar garnish and the air bag, so that a damage to the air bag can be prevented in an ensured manner which would be caused by the interference of the air bag which is being inflated and the other members.