Abstract:
A safety belt system for a vehicle to protect an occupant having an inflatable member attached at one portion to the vehicle with the remainder of the inflatable member free to move along the safety belt during the inflation of the inflatable member. The safety belt system may be buckled up or not during such inflation.

Description:
BACKGROUND OF THE INVENTION 
     It has been proposed to mount inflatable bags on or attach them to vehicle seat belts (U.S. Pat. Nos. 5,135,256 and 5,161,821). In these proposals the inflatable member is positioned around the belt and is not attached to any part of the vehicle other than the belt itself. As the member inflates it does not substantially change its position relative the belt. In another proposal an inflatable bag is positioned around a lap belt and not attached to the belt (U.S. Pat. No. 5,871,230). This proposed system permits the occupant to slide the inflated bag side-to-side on the belt to center it prior to inflation. Once the inflatable bag is positioned it remains in that position when inflated. 
     SUMMARY OF THE INVENTION 
     Broadly, the present invention comprises an arrangement and its method of installation and operation in which a shaped inflatable member is stored adjacent a vehicle seat belt. Upon detection of a collision the inflatable member is inflated. As it deploys it is guided by the seat belt or portion thereof when the occupant is buckled-up. The invention includes an inflatable member and a device to accomplish inflation which inflatable member is preferably positioned around the seat belt or portion thereof. The inflatable member when positioned and actuated serves to protect the occupant. The inflatable member is mounted adjacent the belt prior to inflation and the inflated member travels around or along the belt when the occupant is buckled-up. After full inflation the inflated member reaches its predetermined protective position. 
     It is also a feature that the present invention functions when the seat belt is in its unbuckled or inactive position. The unbuckled belt is guided by the inflatable member as deployed to provide protection. 
     Inflation of the member including its travel along the buckled-up belt portion accomplishes pre-tightening of the belt to retard or reverse occupant movement just prior to and during deceleration of the vehicle. 
     The present invention is useful with any belt system such as a three point system with lap and torso portion, a four or five point harness system, as well as a two point lap belt system. The inflatable member, the inflator, the crash sensor and other associated equipment may be enclosed in a modular unit which may be mounted adjacent portions of the safety belt arrangement. Bags protect the head, neck, shoulder, torso, lap or leg of the occupant. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a perspective view of a vehicle seat in which an inflatable bag of the present invention is stored within the seat back and thereafter deployed with the belt buckled up; 
     FIG. 2 is a perspective view of a seat similar to FIG. 1 showing inflation of the inflatable member with the belt unbuckled; 
     FIG. 3 is a cutaway perspective view of the bag storage unit with housing and gas supply tube; 
     FIG. 4 a  is a sectional view of a bag storage unit of FIG. 3 with the bag folded in the housing and including a retractor from which the belt pays out; 
     FIG. 4 b  is a view similar to FIG. 4 a  with the bag deployed; 
     FIG. 5 is a sectional view and along line  5 — 5  of FIG. 4 a;    
     FIG. 6 a  is a sectional view of the bag storage unit with an alternative bag storage arrangement; 
     FIG. 6 b  is a sectional view taken along line  6   b — 6   b  of FIG. 6 a;    
     FIG. 7 a  is a perspective view of a vehicle seat having a three point belt with the bag storage unit mounted on the seat back; 
     FIG. 7 b  is a perspective view similar to FIG. 6 a  with the bag deployed; 
     FIG. 8 a  is a perspective view of a vehicle seat with two units mounted on the seat back to serve a four point harness belt arrangement; 
     FIG. 8 b  is a view similar to FIG. 7 a  with the bags deployed. 
     FIG. 9 a  is a perspective view of a seat with a two point lap belt with two bag units mounted on the sides of the seat; and 
     FIG. 9 b  is a view similar to FIG. 8 a  with the bags deployed. 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     In FIGS. 1 and 2, seat  10  includes seat portion  11 , back portion  12  and platform support  14 . Belt arrangement  16  includes torso portion  17 , lap portion  18 , latch tongue  20 , retractor  41  and tongue receiver  24 . Torso portion  17  is fed into and out of slot  26  and anchored by a retractor behind the seat (not shown). Inflated bag  33  includes tubular portion  28 t and lower portion  281 . Bag  33  is anchored to a bag storage unit  25  positioned in seat  10 . Unit  25  may be positioned on seat  10  or at other locations in the vehicle. 
     In FIG. 1, with the occupant buckled-up, bag  33  as inflated is positioned between the occupant and torso belt portion  17  to provide protection. Bag portion  281  provides protection for the thorax area of the occupant. In FIG. 2, though belt arrangement  16  is not engaged in tongue receiver  24 , torso belt portion  17  is positioned under influence of deployment of bag  33  in a direction placing bag  33  adjacent the occupant to provide both frontal and side impact protection. The deployment of bag  33  may partially cover belt portion  17  as shown in FIG.  2 . Alternatively, bag  33  may, when deployed, cover more or all of belt portion  17 . Torso belt portion  17  has axis A which includes upper axis Al and lower axis A 2  which axes do not lie in a straight line due to the curvature of belt portion  17  (FIG.  1 ). The axis of bag portion  28 t is coaxial with upper axis A 1 . 
     Turning to FIG. 3, bag storage and deployment unit  25  including housing  27  is positioned in or on a seat or at other appropriate vehicle locations. Housing  27  includes oval back panel  27   a  and oval front panel  27   b  and curved body portion  29 . Front panel  27   b  is preferably made of a light opaque plastic sheet that is ruptured by the exiting bag. Mounted on and projecting from back panels  27   a  is seat belt webbing pass-through guide  31  having exit opening  31   o  similar to slot  26  in FIGS. 1 and 2. Seat belt section  40  passes through guide  31  which is preferably made of a low friction material to facilitate reciprocal movement of belt portion  17  in guide  31 . Seat belt section  40  may be a torso belt portion such as portion  17  of FIGS. 1 and 2. Unit  25  further includes gas supply tube  37  and inflator  38 . Unit  25  is enclosed in modular housing  15  including modular housing  27 , tube  37  and inflator  38  (see FIG. 4 a ). Also shown is crash detector  39 . 
     FIG. 4 a  depicts bag storage housing  27  storing folded bag  33  having bag end  33   e  attached to back panel  27   a  and with hooks  36  for attaching bag  33  to housing  27 . Bag  33  is folded in accordion fashion creating folds  33   f . Gas intake tube  37  supplies gas from an inflator  38 . Seat belt section  40  is payed out of retractor  41  over roller  42 . In FIG. 4 b , bag  33  is shown deployed in its inflated state. Front panel sheet  27   b  is ruptured by the force of the exiting bag  33 . Bag  33  has sufficient fabric thickness so that upon inflation to about ten (10) psi gas pressure bag  33  is projected outwardly partially guided by belt  40 , if the belt is buckled up, to nearly a horizontal position. In FIG. 5, housing  27 , front panel  27   b , bag  33 , pass-through guide  31  and belt portion  40  are shown. 
     Turning to FIGS. 6 a  and  6   b , an alternative bag mount and folding configuration is shown including housing  27 ′ and pass through guide  31 ′ similar to the construction shown in FIGS. 3,  4   a ,  4   b  and  5 . Bag  33 ′ has its end portion  33   e′  held between outer bag retaining ring  44   o  and outer jam ring  45   o  and inner ring  44 ′ and inner jam ring  45 . Bag end  33   e′  is secured by rings  44   o ,  45   o  and  44 ,  45 , squeezing bag end  33 ′ e  sufficiently that it will not release from such position upon inflation. Bag  33 ′ is folded for storage in housing  27 ′ in folds  46 . Gas inlet  37 ′ introduces gas which causes bag  33 ′ to exit housing  27 ′ in direction D and inflate around belt section  40 ′. 
     Comparing the embodiment of FIGS. 3,  4   a ,  4   b  and  5  and the embodiment of FIGS. 6 a ,  6   b , it is seen that in FIGS. 3,  4   a ,  4   b  and  5  by attaching bag end  33   e  to the back panel  27   b  of housing  27  an inflated portion of bag  33  remains in the housing to provide greater stiffness to the bag portion in and adjacent the housing  27 . In contrast, in the embodiment of FIGS. 6 a ,  6   b , by attaching the bag  33 ′ to the exit perimeter  27   p  of housing  27 ′ and the opening edge  31   e  of pass-through  31 ′ (FIGS. 6 a ,  6   b ), the effective deployed length of the bag  33 ′ is increased. 
     Rigidness of bags  33 ,  33 ′ may be increased by using a thicker, stiffer bag material or by increasing the pressure and volume supplied by the inflator or both. Bags of any configured shape may be used. Where bags are non-cylindrical in shape some of folds  33   f ,  46   a-b  may be double folded as positioned in housings  27 ,  27 ′ or may be folded in any other suitable way. During deployment of bag  33 ,  33 ′, the folds  33   f ,  46   a-d  are caused to exit housings  27 ,  27 ′ by the gas pressure. In the initial stages of the deployment gases pass between the folds  33   f ,  46   a-d  and as more gases are supplied bags  33 ,  33 ′ are fully inflated to their effective length (see, for example, FIG.  4 ). 
     In FIGS. 7 a ,  7   b , a bag storage and deployment unit  27  is mounted on the top surface  50   t  of back seat portion  50 . Three (3) point belt arrangement  51  is shown in a buckled-up mode including torso portion  51   t . In FIG. 7 b , bag  33  is shown deployed from unit  27  to a position around torso portion  51   t . In FIG. 7 b , belt portion  51   t  has axis B and inflated member  33  has axis C. Axes B and C do not lie in the same line but are offset by the distance d. 
     In FIGS. 8 a ,  8   b , a four (4) point belt system  56  is shown in buckled-up mode including two (2) torso portions  57   a ,  57   b  and two (2) lap belt portions  58   a ,  58   b  connected by buckle and tongue unit  59 . Two (2) bag units  61 ,  62  are positioned on the top surface  64   t  of seat back portion  64 . FIG. 8 b  shows bags  33  deployed. 
     Finally, in FIG. 9 a , a two (2) point lap belt system  70  including belt portions  71 ,  72  with buckle  73 , and tongue  74  is shown unbuckled. Bag units  76  and  77  (not shown) provide bags  78 ,  79  with upwardly projecting bag sections  78   t  and  79   t . In FIG. 9 b , the buckled  73  and tongue  74  are connected and bags  78 ,  79  inflated. 
     In the operation of the present invention, when the belt arrangement is in its buckled-up mode, the inflated bag or other member is guided by a portion of the belt arrangement as the inflated bag or other member is deployed resulting in 
     a) a consistent and predictable placement of the bag or member as fully deployed; 
     b) the bag or other inflatable member being deployed prior to the occupant starting or substantially progressing in his or her forward (or other directional) movement thus permitting the bag or other member to be introduced between the occupant and the belt arrangement causing the belt arrangement to be pre-tensioned. 
     The bag or other inflatable member is preferably guided, in the buckled-up mode, by a belt portion by surrounding the belt portion but the bag or member alternatively can be guided by the belt through other means such as by shaping the bag so that it has an outer guide channel to facilitate the belt portion guiding the bag or other member as it moves during its inflation. In the unbuckled mode, the bag or other inflatable member guides the belt. 
     Preferably, the axis (whether straight lined or curved) of the belt portion is substantially the same as the axis of a surrounding tubular or cylindrical bag or bag section; however, axes may be parallel, nonparallel, offset or spaced apart, provided the belt portion is positioned, when buckled up, to provide guidance to the bag as it is deployed. 
     Inflatable bags employed with this invention may be of any shape, size or configuration and may be folded and attached to the unit, seat, or other compartment part by appropriate attachment means. Bags may be configured and anchored to protect the head, neck, shoulder, torso, lap and legs of the occupant. 
     Herein “coaxial” refers to an axis of a belt portion and an axis of the inflatable member coinciding, being parallel or having other similar predictable relationship upon inflation of the inflatable member.