Abstract:
A three point integrated seatbelt assembly incorporated into a cantilevered stowable seat with an improved dump locking mechanism. The cantilevered stowable seat can be mounted to a vehicle, where space may be selectively provided for positioning a wheelchair or other article adjacent to the stowed seat, which includes a frame attached to the support member, a cantilevered seatbase, and a seatback. The seatbelt assembly allows for easy storage of the seat and safe transportation of a passenger. The seatback is rotatably associated with the cantilevered seatbase by the improved dump locking mechanism, whereby the improved dump locking mechanism enables the seat to remain in the deployed position when inertial forces are placed on the seatback.

Description:
BACKGROUND OF THE INVENTION  
       [0001]     This invention generally relates to at least one cantilevered stowable seat, and more particularly, pertains to the integration of a seatbelt assembly with a cantilevered stowable seat. The stowable seat cooperates with an improved dump locking mechanism which provides a convenient, unhindered storage area for articles and space for passengers when in the stowed position. Further, the integrated seatbelt assembly and cantilevered seatbase conveniently and firmly secures passengers into the cantilevered seatbase in cooperation with the improved dump locking mechanism that can be easily released from different positions.  
         [0002]     The improved dump locking mechanism that cooperates with the cantilevered seatbase and seatback prevents forward and rearward movement of the seatback while also enabling the seat to be placed in a stowed position. The stowable seat can move to the stowed position with ease due to the integration of the seatbelt assembly and the dump mechanism provides the necessary rigidity to maintain the integrity of the seatback when inertial forces are present.  
         [0003]     Typically, a cantilevered stowable seat is deployed in the industry by having a single leg and frame while the aisle end is legless and is supported by a diagonal support member that is slidable. Formerly, for at least 10 years, a lap type 1 seat belt restraint was used as a seat belt. However, in type 2 seatbelts where there is both a lap restraint and an upper torso restraint system, the slidable diagonal support member is insufficient to sustain forward and rearward forces of a passenger secured by an integrated seatbelt that is not fastened directly to the frame of the vehicle. As such, a stowable seat with an integrated seatbelt that does not rely on the vehicle frame must be designed to stabilize the stowable seat during extreme forces where the forward forces are caused by belt loading and the rearward forces are caused by the weight of the passenger. Belt loading occurs when the occupant engages the restraint system which in turn acts on the seatback and cantilevered seatbase.  
         [0004]     Prior art dump locking mechanisms are complex, heavy, and expensive with locking gears and latches. These dump locking mechanisms, when used in a stowable seat system, would make it difficult to move a stowable seat between stowed and deployed positions. Further, the prior art has included locking mechanisms for stowable seats without integrated seatbelts. These locking mechanisms are insufficient to support the inertial forces present when a passenger is seated in a stowable seat and secured by an integrated seatbelt assembly.  
         [0005]     While there has been a long existing need for stowable seats with integrated seatbelts, up until now the prior art has not solved the problem of inertial impact on the stowable seats where the aisle end of the seats does not have legs. It is important not only for the seat to carry a larger inertial load during frequent stops or accidents, but also to maintain flexibility and the capability to move to a stowed position. Furthermore, a need exists in the relevant art to provide a dump locking mechanism to maximize the structural integrity of the stowable seat and integrated seatbelt system while minimizing the overall cost of the system. Accordingly, this invention solves the problem of the forward and rearward impact of the seats when the seatbelt restraint system that has a type 1 and type 2 belt is associated with the frame of the (see CFR 49 for definitions of “type 1” and “type 2” restraint systems) stowable seatback rather than the frame of the vehicle.  
       SUMMARY OF INVENTION  
       [0006]     Accordingly, it is an object of the present invention to provide a cantilevered stowable seat with an integrated seatbelt assembly and an improved dump locking mechanism to stabilize the stowable seat when the seatbelt assembly is employed. The dump locking mechanism further enables the seatback to be moved to and from the folded position. The cantilevered seatbase with the folded seatback can then rotate to the stowed position and storage space is created for a wheelchair or article adjacent to the stowable seat. The stowable seat includes a seatback, a cantilevered seatbase, a seat frame, a diagonal truss, a seatbelt assembly, a downlock mechanism, an uplock mechanism, and an improved dump locking mechanism. The improved dump locking mechanism enables the seatback to be placed in the unfolded position to provide seating for passengers. Once a passenger is secured into the stowable seat by the integrated seatbelt assembly, the seat is stabilized by the improved dump locking mechanism.  
         [0007]     The preferred embodiment of the invention includes an improved dump locking mechanism comprising an aisle side dump locking mechanism, a metal connecting rod, and a window side dump locking mechanism. The swing plate is pivotally associated with the bracket plate and the swing plate is designed to engage between the metal stop protrusion and the locking plate to support the seatback in the unfolded position. The seatback side plate is pivotally associated with the bracket plate and the seatback plate is designed to engage the locking plate to further define and maintain the seatback in the unfolded position. The seatback stop plate is pivotally associated with the bracket plate and the seatback stop plate maintains a seatback stop pin. The bracket plate is designed to engage the seatback stop pin to define the seatback in the unfolded position.  
         [0008]     The release handle is pivotally associated with the locking plates on both the window and aisle sides of the seat by a metal connecting rod. The release handle disengages the locking plates from the seatback plates, the swing plate, and the fasten plate to enable the folding of the seatback into the folded position. A biasing spring operable on the release handle urges the release handle to force the locking plates back to the locked position. Once the seatback is in the folded position, the swing plate and fasten plate are designed to engage the locking plates in order to hold the seatback in the folded position.  
         [0009]     Once the seatback is in the folded position, the stowable seat can be moved to the stowed position. The cantilevered seatbase is freely and pivotally mounted on an axis that is associated with the seat frame. The cantilevered seatbase cooperates with a diagonal truss supporting the seat to move into the stowed position. A locking mechanism assembly locks the cantilevered seatbase in the stowed position to permit storage of a wheelchair adjacent to the stowed seat. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0010]     The present invention will become more fully understood from a detailed description and accompanying drawings, wherein:  
         [0011]      FIG. 1  is a pictorial view of the stowable seat illustrating the cantilevered seatbase in the deployed position, the seatback in the unfolded position, the seat frame supported by a leg frame and a diagonal truss, and the integrated seatbelt assembly;  
         [0012]      FIG. 2  is a rear view of the deployed seat illustrating the seatback in the unfolded position, the cantilevered seatbase in the deployed position, the gas-charged cylinder, the diagonal truss, and the seat frame supported by a leg frame mounted to the vehicle;  
         [0013]      FIG. 3  is a rear view of the stowable seat illustrating the connection of the seatbelt webbing retractor;  
         [0014]      FIG. 4  is a front sectional view of the cantilevered seatbase illustrating the connection between the metal rods, the cantilevered seatbase locking plates, and the release handles. It also illustrates the uplock and downlock mechanism that includes a slide member and release handle;  
         [0015]      FIG. 5  is a side view of the aisle side dump locking mechanism. This illustrates how the aisle side of the seatback is maintained in a substantially unfolded position as referred to by the arrows  5  in  FIG. 2 ;  
         [0016]      FIG. 6  is a side view of the window side dump locking mechanism illustrating how the window side of the seatback is maintained in a substantially unfolded position as referred to by arrows  6  in  FIG. 2 ;  
         [0017]      FIG. 7  is a side view of the release handle illustrating how the locking plate on the aisle side and the connecting metal rod are pivotally associated with the release handle;  
         [0018]      FIG. 8  is a side view of the window side locking plate illustrating how the locking plate on the window side is pivotally associated with the connecting metal rod;  
         [0019]      FIG. 9  is a perspective cutaway view from the window side of both the aisle and window side dump mechanisms. This figure illustrates the positioning of the swing plate and the fasten plate when in the deployed position. Also shown is the swing plate engaging both the metal stop protrusion and the locking plate;  
         [0020]      FIG. 10  is a side view of the aisle side dump locking mechanism illustrating the positioning of the swing plate when the stowable cantilevered seat is in a substantially unfolded position;  
         [0021]      FIG. 11  is a side view of the aisle side dump locking mechanism illustrating the positioning of the swing plate when the spring biased release handle is pulled to disengage the locking plate;  
         [0022]      FIG. 12  is a side view of the aisle side dump locking mechanism illustrating the positioning of the swing plate when the seatback is in a substantially folded position and the locking plate is engaged;  
         [0023]      FIG. 13  is a perspective cutaway view from the aisle side of both the aisle and window side dump mechanisms. This figure illustrates both locking plates engaging with the seatback plates;  
         [0024]      FIG. 14  is a side view of the window side dump mechanism illustrating the positioning of the fasten plate when the stowable cantilevered seat is in a substantially unfolded position.  
         [0025]      FIG. 15  is a side view of the window side dump mechanism illustrating the positioning of the fasten plate with relation to the locking plate after the spring biased release handle is pulled and the stowable cantilevered seat is in a substantially folded position. 
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0026]     Referring to the drawings, there is shown cantilevered stowable seat  76  with integrated seatbelt assembly  46  that has particular utility for public and private transportation. As illustrated in  FIGS. 1 and 2 , cantilevered stowable seat  76  includes leg frame  7 , cantilevered seatbase  1 , seatback  3 , seatbelt assembly  46 , and diagonal truss  4 .  
         [0027]     In operation, cantilevered stowable seat  76  is positioned with cantilevered seatbase  1  in a deployed position and seatback  3  in an unfolded position. Passengers employ the integrated seatbelt system to secure themselves with shoulder and lap portions of seatbelt webbing  50 . Cantilevered seatbase  1  is supported by leg frame  7  and diagonal truss  4 . Cantilevered seatbase  1  and seatback  3  rotate to the stowed position after seatback  3  has been folded over to a position flat against cantilevered seatbase  1  to provide space for a wheel chair or other article. The positioning of integrated seatbelt assembly  46  enables cantilevered stowable seat  76  to rotate to the stowed position without interference from overhead belts attached to the vehicle frame that are typically found in passenger vehicles. Diagonal truss  4  may be locked into position to hold cantilevered stowable seat  76  in the stowed position.  
         [0028]     Leg frame  7  and floor mount legs  6  fixedly attach to frame plate  30 , thus securing cantilevered stowable seat  76  to the floor of a vehicle. Frame plate  30  is preferably constructed of steel having bolt holes for mounting or other similar means.  
         [0029]     As seen in  FIG. 2 , cantilevered seatbase  1  is generally rectangular having a cover and removably attached to leg frame  7 . Gas charged cylinder  26  is removably attached to cantilevered seatbase  1  to provide a lifting force while rotating the seat to the stowed position. In  FIG. 2 , gas charged cylinder  26  is connected to inner frame of cantilevered seatbase  1  and leg frame  7 . Diagonal truss  4  is generally rectangular and, in cooperation with frame plate  30 , supports cantilevered seatbase  1  in the deployed position.  
         [0030]      FIG. 5  illustrates aisle side dump locking mechanism  78  which includes bracket plate  40  removeably attached to outer frame of cantilevered seatbase  1 . Bracket plate  40  may be mounted in position by bolts, welding, or other similar fastening methods. Seatback side plate  55  is fixedly attached to the inner frame of seatback  3 . Seatback stop plate  56  is fixedly attached to seatback  3 . Seatback side plate  55  and seatback stop plate  56  may be mounted in position by welding or other similar fastening methods. Seatback side plate  55  and seatback stop plate  56  are pivotally associated with bracket plate  40  by pivot pin  34  in order to pivotally mount seatback  3  on cantilevered seatbase  1 .  
         [0031]     As illustrated in  FIG. 9 , bracket plate  40  includes metal stop protrusion  41 . Swing plate  54  is pivotally mounted to bracket plate  40  with pivot pin  34  and is removably associated to the inner side of seatback side plate  55  with bolt  33 . Seatback plate  55  includes cylindrical studs  32  where leaf spring  31  is secured to reinforce and maintain the position of swing plate  54 . Swing plate  54  maintains an end point to engage metal stop protrusion  41  when seatback  3  is in the unfolded position preventing seatback  3  from tilting further rearwards. Seatback stop pin  42  may be securely mounted to seatback stop plate  56  by welding or similar mounting methods. Bracket plate  40  is designed to engage seatback stop pin  42  in order to further prevent rearward movement of seatback  3 . Seatback plate  55  is mounted to the inner side of seatback  3  and is pivotally associated with bracket plate  40 . As in  FIGS. 6 and 7 , seatback plate  55  is designed to engage locking plate  11  in order to prevent seatback  3  from tilting forward when the passenger is secured by seatbelt assembly  46 . Locking plate  11  is pivotally mounted to cantilevered seatbase  1  by pivot pin  37 .  
         [0032]     In  FIG. 6 , window side dump locking mechanism  77  comprises seatback plate  55   a  fixedly attached to the inner frame of seatback  3  and bracket plate  40   a  which is removably associated with cantilevered seatbase  1 . Seatback plate  55   a  pivotally associates with bracket plate  40   a  at pivot pin  34   a  to pivotally mount seatback  3  with cantilevered seatbase  1 . Seatback stop pin  42   a  extends from seatback plate  55   a.  Bracket plate  40   a  is designed to engage seatback stop pin  42   a  when seatback  3  is in the unfolded position to further restrain seatback  3  from rearward movement. As in  FIG. 8 , locking plate  11   a  is pivotally mounted to cantilevered seatbase  1  by pivot pin  37   a.  Seatback plate  55   a  maintains an engagement surface to abut locking plate  11   a,  which restrains seatback  3  from forward motion when a passenger is secured by seatbelt assembly  46 . Fasten plate  57  is pivotally associated to seatback plate  55  with pivot pin  39 . As illustrated in  FIGS. 14 and 15 , fasten plate  57  is slidably associated with bracket plate  40  by bolt  39  which slides along track  61  in fasten plate  57 . Fasten plate  57  is designed to move into engagement with window side locking plate  11   a  when seatback  3  is in the unfolded position in order to restrain seatback  3  from moving.  
         [0033]     As seen in  FIGS. 5 and 7 , locking plate  11  and spring biased release handle  10  are pivotally attached to seatbase  1  via pivot pin  37 . Spring biased release handle  10  and metal rod  5  are pivotally mounted to locking plate  11  with pivot pin  68 .  FIG. 4  illustrates how metal rod  5  extends from locking plate  11  to locking plate  11   a  and is pivotally mounted to locking plate  11   a  by pivot pin  68   a.  Spring  44  is associated with spring biased release handle  10  while in the locked position as shown in  FIGS. 5 and 7 . Spring  44  biases locking plates  11  and  11   a  into the locked position to engage with seatback plates  55  via metal rod  5  to hold seatback  3  in the unfolded position  
         [0034]     An operator can pull spring biased release handle  10  to release seatback  3  to rotate to the folded position. When an operator pulls spring biased release handle  10 , locking plates  11  and  11   a  simultaneously pivot downward into cantilevered seatbase  1 , disengaging seatback side plates  55  &amp;  55   a  and swing plate  54 ; and consequently, enabling seatback  3  to rotate to the folded position.  FIG. 12  illustrates the positioning of aisle side dump mechanism  78  when seatback  3  is in the substantially folded position. Swing plate  54  has slidable track  59  and is removably attached to seatback plate  55  via bolt  34 . Once locking plate  11  disengages swing plate  54  and seatback  3  begins to dump, swing plate  54  maintains engagement with metal stop protrusion  41  biased by leaf spring  31 . Leaf spring  31  is attached to seatback plate  55  with cylindrical studs  32 .  
         [0035]     As in  FIG. 13 , spring  44  biases spring biased release handle  10  and locking plates  11  and  11   a  to simultaneously pivot to the locked position. Locking plates  11  and  11   a  engage swing plate  54  on the aisle side and fasten plate  57  on the window side to restrict seatback  3  from moving upwards to its unfolded position.  
         [0036]     To enable seatback  3  to pivot to the folded position, spring biased release handle  10  is pulled by an operator to lower locking plates  11  and  11   a  to disengage swing plate  54  and fasten plate  57  as shown in  FIGS. 12 and 15 . Swing plate  54  and fasten plate  57  are no longer restricted by locking plates  11  and  11   a;  therefore, seatback  3  is enabled to rotate to the folded position. In the folded position, spring biased release handle  10  forces locking plates  11  and  11   a  to engage with seatback side plates  55  and  55   a  to hold seatback  3  in its folded position.  
         [0037]     Referring to  FIG. 4 , uplock mechanism  62  keeps the stowable seat in the deployed position. Uplock release handle  69  enables an operator to pivot and release uplock mechanism  62  and enables slide member  60  to travel along runner track  58  to rotate cantilevered stowable seat  76  to the stowed position.  
         [0038]     To keep cantilevered stowable seat  76  in the stowed position, downlock mechanism  66  constrains slide member  60  of diagonal truss  4  within runner track  58 . Once an operator forces spring biased release handle  10  upward to pivot and release downlock mechanism  66 , slide member  60  is released and cantilevered stowable seat  76  may be rotated to the deployed position.  
         [0039]     As seen in  FIGS. 1, 2  and  3 , integrated seatbelt assembly  46  includes seatbelt webbing  50 , webbing slit  49 , webbing retractor  51 , clasp  52 , buckle  53 . Seatbelt buckle  53  receives seatbelt clasp  52 , and seatbelt buckle  53  is fixedly attached to the front of webbing retractor  51 . Seatbelt webbing  50  has a first end releasably extending from webbing retractor  51  that is securely anchored to the bottom back end of seatback  3 . Webbing  50  extends upwardly along seatback  3  and passes through webbing slit  49  at the upper end of seatback  3  and then downwardly along the front surface of seatback  3  to seatbelt clasp  52 .  
         [0040]     It should be appreciated that the present invention provides a seating system that has an integrated three point safety belt that functions with a stowable seat. In particular, the cantilvered stowable seat employs a dump locking mechanism having specifically designed plates to secure the seatback when there is passenger loading. The three point integrated seatbelt system with improved dump locking mechanism will achieve more safety in vehicles with stowable seats.  
         [0041]     The foregoing detailed description of the invention shows how the objects of the present invention have been obtained in a preferred manner. However, other embodiments, modifications, and equivalents of the disclosed concepts such as readily occur to those skilled in the art are intended to be included within the scope of the invention. The above has been offered for illustrative purposes only and is not intended to limit the scope of the invention of this application, which is defined in the claims below: