Patent Publication Number: US-RE37123-E

Title: Seat and occupant restraint system

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     This invention is in the field of tethers, harnesses, and other restraint systems used in vehicles. 
     2. Description of the Prior Art 
     A variety of different types of restraint systems have been devised for securing passengers, cargo and seats within a vehicle. For example, the commonly owned U.S. Pat. No. 5,015,010 discloses a tether securing a seat frame to a vehicle floor, a three point belt system entirely mounted to the seat frame restraining the seat occupant, and a retractor belt combination extending between the vehicle floor and the top of the seat isolating the seat back from passenger force exerted against the seat belt. 
     In order to limit seat movement during a crash, it has been the practice to tether the seat to the floor; however, a fixed tether limits the horizontal adjustability of the seat. In the commonly owned U.S. Pat. No. 5,219,207, an automatic locking tether for the vehicle seat is disclosed wherein the seat may be horizontally adjusted to the specific requirements of the occupant. Passenger loading during a crash results in the automatic locking of the tether. 
     Seats provided within large trucks typically are suspendedly mounted atop the vehicle floor. For example, a cushioned air bag may be positioned between the bottom of the seat and floor thereby providing a cushioned ride. Such seats are typically positioned a substantial distance from the vehicle floor. It is therefore desirable to provide a restraint system which will move the seat and occupant toward the floor during a crash thereby providing a more compact seat occupant envelope. Disclosed herein is such a system. 
     SUMMARY OF THE INVENTION 
     One embodiment of the present invention is a device for retracting a vehicle seat having a seat back during a crash of the vehicle comprising a seat retractor connected between the seat and the vehicle and operable upon crash of the vehicle to move the seat toward the floor. 
     Another embodiment of the present invention includes a seat retractor upon crash of a vehicle for moving the vehicle seat toward the vehicle floor. The seat retractor has a belt device mounted to the seat to restrain an occupant thereon. A belt retractor is connected between the seat retractor and the belt device and is operable upon crash of the vehicle to tighten the belt device prior to the seat retractor moving the seat toward the floor. 
     It is an object of the present invention to provide a restraint system for a vehicle seat and occupant. 
     A further object of the present invention is to provide a restraint system for moving a vehicle seat towards the vehicle floor during a crash. 
     An additional object of the present invention is to provide a restraint system operable upon crash of the vehicle to first tighten the seat belt and then move the seat with occupant towards the vehicle floor. 
     Related objects and advantages of the present invention will be apparent from the following description. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a side view of a vehicle seat showing vertical excursion. 
     FIG. 2 is a front view of the preferred embodiment of the seat incorporating the present invention. 
     FIG. 3 is a side view of a first alternate embodiment of the seat incorporating the present invention. 
     FIG. 4 is an enlarged fragmentary view of the seat of FIG. 3 in a normal mode. 
     FIG. 5 is the same view as FIG. 4 only showing the seat in the crash mode. 
     FIGS. 6-9 are side diagrammatic views of various alternate linkages for the seat of FIGS.  2  and  3 . 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT EMBODIMENTS 
     For the purposes of promoting an understanding of the principles of the invention, reference will now be made to the embodiment illustrated in the drawings and specific language will be used to describe the same. It will nevertheless be understood that no limitation of the scope of the invention is thereby intended, such alterations and further modifications in the illustrated device, and such further applications of the principles of the invention as illustrated therein being contemplated as would normally occur to one skilled in the art to which the invention relates. 
     FIG. 1 depicts a typical suspension seat  10  utilized in a heavy truck. Seat  10  is mounted by means of an air bag within housing  13  atop vehicle floor  12 . Occupant  11  is secured within the seat by means of a conventional three point belt assembly  14  with the belt extending through a D-loop  15  mounted to the B pillar of the truck. One end of the belt is secured to a retractor mounted either directly to the vehicle or to the frame of the seat. Dash line  16  depicts the upper limit of the vertical movement of the occupant. The amount of vertical movement will vary with each type of seat; however, a typical seat has a vertical movement of approximately four inches unless the vehicle rolls over in which case the vertical movement may increase to approximately nine inches when the vehicle is in an upsidedown condition. 
     FIGS. 2 and 3 illustrate respectively the preferred and alternate embodiments of the restraint systems incorporating the present invention. Seats  30  of FIGS. 2 and 3 are identical except in FIG. 2 the retractor and D-loop used with the seat belt are mounted external of the seat, whereas in FIG. 3 the D-loop and associated retractor are mounted directly to the seat. In FIG. 3 an additional retractor and associated belt are used to isolate the seat back from passenger force applied to the belt during a crash. The restraint systems incorporating the present invention for moving the seat and occupant toward the vehicle flow are identical for use with the seats of FIGS. 2 and 3. 
     The conventional truck suspension vehicle seat includes an air or fluid bag  32  (FIG. 3) positioned between the bottom of the seat frame and vehicle floor  12 . A pair of links  33  and  34  have their opposite ends pivotally mounted to depending brackets  36  attached to the seat frame and an upwardly extending bracket  35  mounted atop floor  12 . Links  33  and  34  and brackets  35  and  36  are provided on each side of the seat allowing the seat to move vertical in a controlled manner. A conventional shock absorbing telescoping device  31  is fixed to and extends between the bottom of the seat frame and bracket  35 . Device  31  is not shown in FIG. 2 to more clearly illustrate bag  32 . The occupant may adjust the height of the seat by controlling the fluid pressure to bag  32 . Conventional fluid controls are provided connecting the air bag to a source of pressurized fluid such as air. 
     A three point belt assembly  40  (FIG. 2) has one end of the belt attached to retractor  41  mounted to the vehicle floor with the belt then extending upwardly through a D-loop  42  mounted to the vehicle B pillar. The belt extends downwardly from D-loop  42  across the occupant and slidably through a conventional seat belt tongue  44  with the belt then extending from the tongue across the lap of the occupant with the opposite end  43  of the belt  88  connected to the restraint device  50  incorporating the present invention. A conventional seat belt buckle  45  is releasably lockable with tongue  44  and is mounted to a strap or other extending member  46 , in turn, having its opposite end connected to restraint device  51 . Restraint devices  50  and  51  are identical and are operable to pull the three point belt assembly  40  and seat downwardly in the crash mode. 
     The three point belt assembly  60  shown in FIG. 3 is identical to the three point belt assembly  40  with the exception that D-loop  61  is mounted directly to the back of the seat as contrasted to the mounting of D-loop  42  to the B pillar. Further, one end of the belt utilized in the three point belt assembly  60  is connected to retractor  62  mounted directly to the seat frame. Thus, in the embodiment shown in FIG. 3, the belt extends upwardly from retractor  62  through D-loop  61  and then downwardly across the occupant with the belt then slidably extending through tongue  44  with the opposite end of the belt being attached to a restraint device  50  positioned on the opposite side of the seat from that depicted in FIG.  3 . Likewise, buckle  45  in FIG. 3 is connected to a belt, cable  46  or other elongated device, in turn, connected to restraint device  51 . A three point belt assembly and D-loop, wherein the D-loop is mounted to the B pillar but the retractor for the three point belt assembly is mounted directly to the seat frame is disclosed in the commonly owned U.S. Pat. No. 5,176,402 which is herewith incorporated by reference. 
     In FIG. 3, an additional retractor  70  is mounted directly to the vehicle having a belt  71  which extends upwardly through guide  72  affixed to the B pillar with the end of the belt attached to D-loop  61  such as shown in the commonly owned U.S. Pat. No. 5,015,010 which is herewith incorporated by reference. Retractor  70  is therefore operable to isolate the seat back from the forces exerted by the passenger against the three point belt assembly  60  by directing the forces directly from the belt to D-loop  61  and then via belt  71  to the vehicle instead of directing the force to the back of the seat for absorption. 
     Restraint devices  50  and  51  are identical and thus the following description for restraint device  51  will apply equally to device  50 . Restraint device  51  is depicted in FIG. 4 in the normal mode and in FIG. 5 in the crash mode. The restraint device includes a fluid cylinder  75  pivotally mounted to vehicle floor  12 . The cylinder has an extendable and retractable piston rod  76  with cylinder  75  connected to a source of pressurized fluid  77  via fluid lines  78  and  79 . A conventional motion sensor  80  is connected via conventional circuitry to source  77  and is operable when the vehicle crashes to detect changes in velocity activating the source of pressurized fluid  77  and causing cylinder  75  to retract piston rod  76 . 
     The outer distal end of piston rod  76  is pivotally mounted by pivot joint  83  to a timing plate  81  pivotally mounted by pivot joint  85  to seat frame  82 . Seat belt buckle  45  is connected by member  46  by pivot joint  84  to timing plate  81 . Prior to crash, pivot joint  85  is located at a position spaced apart from axis  87  (FIG. 4) which extends along the length of pivot rod  76 . Once sensor  80  has detected a change in vehicle velocity, piston rod  76  is retracted thereby pivoting timing plate  81  in a clockwise direction, as viewed in FIG. 4, about pivot joint  85  until pivot joint  85  is located on axis  87 . As plate  81  moves from the position of FIG. 4 to the position of FIG. 5, buckle  45 , tongue  44  and the three point belt assembly will be pulled downwardly and tightened thereby moving the occupant downwardly into the cushion of the seat. Simultaneously, the opposite end  43  (FIG. 2) of the lap portion  88  of the belt is pulled downwardly by restraint device  50  and retractor  41  or  62  lock preventing further extension of the belt. Even though retractors  41  and  62  have locked, the retracting devices  50  and  51  will pull the occupant and seat downwardly towards the vehicle floor since the belt in the three point belt assembly will stretch and further due to the normal slack existing in the three point belt assembly. Once plate  81  has pivoted to the position depicted in FIG. 5, pivot joint  85  is located on axis  87  and further retraction of rod  76  will pull seat frame  82  downwardly toward the vehicle floor. Various timing linkages are possible in addition to the timing plate  81 . Such alternate linkages are depicted in FIGS. 6-9. 
     Fluid cylinder  100  is pivotally mounted to the vehicle floor and has an extendable and retractable piston rod  101  with a distal end  106  pivotally connected to plate  104 . Buckle  45  is connected to member  46  in turn pivotally connected by joint  105  to plate  104 . Buckle  45  along with sensor  80  and the source of pressurized fluid  77  have not been shown in FIGS. 6-9; however, it is to be understood that the buckle and source of pressurized fluid are connected respectively to member  46  and the fluid cylinder in a manner similar to that depicted in FIG.  4 . Projection  102  is fixedly mounted to seat frame  82  and is slidable within slot  103  of plate  104 . Retraction of rod  101  causes end  106  and plate  104  to move downwardly thereby pulling downward buckle  45  and the attached three point belt assembly. Eventually, projection  102  will reach the top end of slot  103  thereby transferring the downward pull to seat frame  82  forcing the seat downward. Plate  104  is pivotally mounted to projection  102  allowing the buckle to be positioned conveniently with respect to the seat occupant. 
     Fluid cylinder  110  (FIG. 7) is pivotally mounted to the vehicle floor and has an extendable piston rod  111  with a distal end  112  pivotally connected to linkage  113 . End  112  of rod  111  is positioned at one end of linkage  113  and is also connected via pivot joint  114  to member  46 , in turn, attached to buckle  45 . The opposite end of linkage  113  is connected via pivot joint  115  to seat frame  82 . Retraction of rod  111  results in the downward movement of pivot joint  114  and member  46  along with the three point belt assembly pulling the occupant downward until eventually linkage  113  has pivoted sufficiently clockwise to align pivot joints  114  and  115  with the longitudinal axis of rod  111  thereby transferring the downward force to seat frame  82  and pulling the seat downwardly towards the floor. 
     Fluid cylinder  120  (FIG. 8) is pivotally mounted to the vehicle floor and has an extendable piston rod  121  with an outer distal end  122  pivotally connected to one end of linkage  123  with the opposite end of the linkage tethered to the vehicle floor by means of cable or web  124 . Linkage  123  is pivotally mounted to the seat extension  82  via pivot joint  125  whereas member  46  attached to buckle  45  is pivotally connected to the distal end  122  of piston rod  121 . Thus, retraction of piston rod  121  results in the clockwise rotation of linkage  123  about pivot joint  125  until cable  124  assumes a taut condition. Prior to cable  124  becoming taut, retraction of piston rod  121  will pull the three point buckle assembly downward. Once cable  124  is taut, further retraction of piston rod  121  will result in the downward force being applied to pivot joint  125  pulling the seat downwardly. 
     Fluid cylinder  130  (FIG. 9) is pivotally mounted to the vehicle floor and has an extendable piston rod  131  with an outer end  133  pivotally connected to plate  132  having a slot  134  through which projection  135  extends. Projection  135  is fixedly mounted to seat extension  82  and is slidable along the length of slot  134 . The opposite end of plate  132  is connected to the vehicle floor by means of rigid member  136 . Member  46  connected to buckle  45  is pivotally connected to the distal end  133  of piston rod  131 . Thus, retraction of piston rod  131  results in downward force being applied to the buckle thereby pulling downward the three point buckle assembly until eventually plate  132  moves sufficiently positioning projection  135  at the upper end of slot  134 . Further retraction of piston rod  131  thereby transfers the downward pull to projection  135  and the seat frame resulting in the seat being pulled downwardly toward the floor. As shown in FIG. 2, the seat is equipped with a restraint device  50  and  51  on the opposite sides of the seat. Thus, the fluid cylinders and accompanying linkages depicted in FIGS. 6-9 are positioned on each side of the seat in a manner similar to that depicted in FIG.  2 . While the invention has been illustrated and described in detail in the drawings and foregoing description, the same is to be considered as illustrative and not restrictive in character, it being understood that only the preferred embodiments have been shown and described and that all changes and modifications that come within the spirit of the invention are desired to be protected.