Abstract:
A vehicle seat structure having a one-piece flexible shell incorporated in the seating surface portion and a one-piece flexible shell incorporated in the backrest portion, wherein dampening means is provided between the shell and the seat frame for added comfort and vibration isolation.

Description:
FIELD OF THE INVENTION  
         [0001]    The invention relates to a seat structure and more particularly to a vehicle seat structure having a one-piece flexible shell used for the seating surface and a one-piece flexible shell for the backrest, each-shell having dampening means provided between the shell and the seat frame.  
         BACKGROUND OF THE INVENTION  
         [0002]    Seats used in automobiles, trucks, and other vehicles may be relatively complex structures. Conventional vehicle seats included a structural frame, springs, and padding that are upholstered with cloth, leather or vinyl. New developments in vehicle seat design have lead to incorporating foam and other engineering materials to eliminate inner spring construction. Generally, a specially contoured frame is covered with foam on all sides and a complex cover is fabricated to encase the entire vehicle seat structure with cloth, leather or vinyl.  
           [0003]    Vehicle seats must meet standards for strength and durability. In addition, vehicle seats must offer design flexibility to allow them to be adapted to various passenger compartment configurations, adjustment mechanisms, and other accessories. Vehicle seats must also allow for efficient utilization of expensive seating fabrics and leather treatments that are frequently demanded by consumers.  
           [0004]    Other important considerations in vehicle seat design are cost constraints. Vehicle seat designs should maximize efficient use of materials and ideally reduce labor requirements to provide maximum value.  
           [0005]    It would be desirable to produce a vehicle seat structure which minimizes the complexity of the seat design and while maximizing passenger comfort.  
         SUMMARY OF THE INVENTION  
         [0006]    Consistent and consonant with the present invention, a vehicle seat structure which minimizes the complexity of the seat design and while maximizing passenger comfort has surprisingly been discovered.  
           [0007]    The vehicle seat structure comprises a support frame adapted to be connected to a vehicle frame; a seating surface portion connected to the support frame, the seating surface portion including a seating surface shell; a backrest portion pivotally connected to at least one of the support frame and the seating surface portion, the backrest portion including a backrest frame and a backrest shell; a plurality of seating dampener structures connecting the seating surface shell to the support frame to permit relative movement therebetween; and a plurality of backrest dampener structures connecting the backrest shell to the backrest frame to permit relative movement therebetween. 
       
    
    
     DESCRIPTION OF THE DRAWINGS  
       [0008]    The above, as well as other advantages of the present invention, will become readily apparent to those skilled in the art from the following detailed description of a preferred embodiment when considered in the light of the accompanying drawings in which:  
         [0009]    [0009]FIG. 1 is a schematic view shown in side elevation of a vehicle seat structure in accordance with the present invention;  
         [0010]    [0010]FIG. 2 is a perspective view of a vehicle seat structure in accordance with the present invention shown without padding and upholstery;  
         [0011]    [0011]FIG. 3 is a partial perspective view of a seating surface dampening structure in accordance with the present invention;  
         [0012]    [0012]FIG. 4 is a perspective view of a second embodiment of the invention showing a seating surface supported by springs;  
         [0013]    [0013]FIG. 5 is a perspective view of the seating surface illustrated in FIG. 4, also showing the backrest portion of the vehicle seat structure; and  
         [0014]    [0014]FIG. 6 is a perspective view of a third embodiment of the invention showing a seating surface wherein the shell is produced from a steel wire. 
     
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT  
       [0015]    Referring now to the drawings, and particularly FIG. 1, there is shown generally at  10  a vehicle seat structure incorporating the features of the invention. The vehicle seat structure  10  has a seating surface portion  12  and a backrest portion  14 . The seating surface portion  12  is supported by a supporting frame  16 , which is attached to a frame structure (not shown) of a vehicle. A headrest portion  18  is attached to a top portion of the backrest portion  14  to support the head of a passenger  20  of the vehicle.  
         [0016]    Referring now to FIG. 2, there is shown the vehicle seat structure  10  without padding and upholstery. The seating surface portion  12  includes a seating surface shell  21  formed of plastic or other durable and flexible material and shaped to be a sitting surface of the vehicle seat structure  10 . The seating surface shell  21  is coupled to the support frame by a plurality of dampener or suspension structures  22 , as clearly illustrated in FIG. 3. In the embodiment shown, two dampener structures  22  are included at the front portion of the seating surface portion  12 . At least one dampener structure  22  must also be included at the rear portion of the seating surface portion  12  to adequately support the seating surface portion  12 . It is understood that more or fewer dampener structures  22  can be used as desired, without departing from the scope and spirit of the invention. The dampener structures  22  include a rubber coupling  24  disposed between a first bracket  26  and a second bracket  28 . Other dampening structures can be used such as a mechanical active dampening type and a hydraulic active dampening type, for example.  
         [0017]    The first bracket  26  is adapted to be received by a first rail  30  of the support frame  16  and a second rail  32  of the support frame  16 . The first bracket  26  is slidable along the first rail  30  and the second rail  32 . The second bracket  28  is connected to an inner surface of the seating surface portion  12 .  
         [0018]    The backrest portion  14  includes a backrest shell  34  formed of plastic or other durable and flexible material and shaped to be a backrest surface of the vehicle seat structure  10 . A side bolster  36  is included on each side of the backrest shell  34 . A plurality of slits  38  are provided on each bolster  36  for added flexibility. A lumbar support structure  40  is provided on the lower portion of the backrest shell  34 . A lumbar support acuator  42  is operatively engaged with the lumbar support structure  40  and is disposed on a backrest frame  44 . The backrest frame  44  includes a first upright leg  46  and a second upright leg  48 . A first hinge  50  is pivotally mounted on an inner surface of the first leg  46 . A second hinge  52  is pivotally mounted on an inner surface of the second leg  48 .  
         [0019]    A backrest mounting structure  54  supports the backrest shell  34  and is pivotally connected to the first hinge  50  and the second hinge  52  and slidingly connected with a headrest frame  56 . One end of a first dampening strucure or spring  58  is connected to the pivotal connection of the first hinge  50  and the backrest mounting structure  54 . The other end of the first spring  58  is connected to the first leg  46 . One end of a second dampening strucure or spring  60  is connected to the pivotal connection of the second hinge and the backrest mounting structure  54 . The other end of the second spring  60  is connected to the second leg  48 . The backrest frame  44  is pivotally connected to the support frame  16  by an elongate rod  62 . It is understood that other pivotal connecting structures could be used without departing from the scope and spirit of the invention. Other dampening structures can be used such as a mechanical active dampening type and a hydraulic active dampening type, for example.  
         [0020]    In operation, as the weight of the passenger  20  is applied to the seating surface shell  21 , the dampening structure  22  adjusts the position of the seating surface shell  21  according to the weight distribution. The first bracket  26  and the second bracket  28  are permitted to move relative to one another by the rubber coupling  24  to facilitate the position adjustment. The dampening structure  22  of the seating surface shell  21  also minimizes the amount of vibration transferred from the vehicle to the passenger  20 .  
         [0021]    As the weight of the passenger  20  is applied to the backrest shell  34 , the first hinge  50  and the second hinge  52  are caused to pivot to adjust the position of the backrest shell  34  according to the weight distribution. The first spring  58  and the second spring  60  are connected to the first hinge  50  and the second hinge  52 , respectively, as well as the backrest mounting structure  54 , to assist in dampening vibration transferred from the vehicle. Thus, the springs  58 ,  60 , the hinges  50 ,  52 , and the backrest mounting structure  54  cooperate to minimize the amount of vibration transferred from the vehicle to the passenger  20 . Additionally, the lumbar support structure  40  can be adjusted for the comfort of the passenger  20  as desired using the actuator  42 . Turning the actuator  42  causes a first flap  64  and a second flap  66  to be urged forward into contact with the lumbar region of the back of the passenger  20  or rearward and out of contact with the lumbar region of the passenger  20 .  
         [0022]    The seating surface shell  21  and the backrest shell  34  each provide a unitary structure under the upholstery and padding of the vehicle seat structure  10  to evenly and comfortably support the passenger  20 . Thus, the seating surface portion  12  and the backrest portion  14  cooperate to support the passenger  20  on the vehicle seat structure  10  and isolate the passenger  20  from the vibration of the vehicle.  
         [0023]    Referring now to FIG. 4, there is shown a second embodiment of the invention. A seating surface portion is shown generally at  70 . The seating surface portion  70  includes a seating surface shell  72  formed of plastic or other durable and flexible material. A pair of elongate frame members  74 ,  76  depend from the seating surface shell  72 . The frame members  74 ,  76  are spaced apart and substantially parallel. The frame member  74  includes an aperture  78 ,  80  formed in each end thereof. A pair of apertures  82 ,  84  is formed in each end of the frame member  76 . A first rail  86  is disposed adjacent one end of the frame members  74 ,  76  and a second rail  88  is disposed adjacent the other end of the frame members  74 ,  76 . The first rail  86  and the second rail  88  are adapted to be connected to a support frame (not shown). A plurality of dampening structures or springs  90 ,  92 ,  94 ,  96  have one end disposed in each of the apertures  78 ,  80 ,  82 ,  84 . The other end of the spring  90  is connected to a first end of the rail  86 , and the other end of the spring  92  is connected to the second end of the rail  86 . Similarly, the other end of the spring  94  is connected to a first end of the rail  88 , and the other end of the spring  96  is connected to a second end of the rail  88 . Although four springs  90 ,  92 ,  94 ,  96  are shown, it is understood that more or fewer springs can be used as desired without departing from the scope and spirit of the invention.  
         [0024]    Referring now to FIG. 5, the seating surface portion  70  is shown connected to a backrest portion  98 . The backrest portion  98  includes a backrest shell  100 . The backrest shell includes a pair of elongate frame members  102 ,  104 . The frame members  102 ,  104  are spaced apart and substantially parallel. One end of the frame members  102 ,  104  are hingedly connected to the seating surface portion  70  to permit pivotal movement therebetween. A first cross-brace  106  extends between the frame members  102 ,  104  adjacent one end thereof. A second cross-brace  108  extends between the frame members  102 ,  104  adjacent the other end thereof. A support frame  110  is hingedly connected to the first rail  86  and the second rail  88  of the seating surface portion  70  to permit pivotal movement therebetween. One end of a dampening strucure or spring  112  is connected to a first end of the first cross-brace  106  and one end of a dampening strucure or spring  114  is connected to a second end of the first cross brace  106 . The other end of the springs  112 ,  114  is connected to the support frame  110 . One end of a dampening strucure or spring  116  is connected to a first end of the second cross-brace  108  and one end of a dampening strucure or spring  118  is connected to a second end of the second cross brace  108 . The other end of the springs  116 ,  118  is connected to the support frame  110 . Although four springs  112 ,  114 ,  116 ,  118  are shown, it is understood that more or fewer springs can be used as desired without departing from the scope and spirit of the invention.  
         [0025]    In operation, the springs  90 ,  92 ,  94 ,  96  and the springs  112 ,  114 ,  116 ,  118  permit the seating surface shell  72  and the backrest shell  100  to be isolated from the first rail  86 , the second rail  88 , and the support frame. The seating surface shall  72  and the backrest shell  100  are supported as a unitary structure. It is understood that the seating surface shell  72  and the backrest shell  100  can be supported independently of one another as shown in FIG. 2.  
         [0026]    As the weight of a passenger (not shown) is applied to the seating surface shell  72 , the springs  90 ,  92 ,  94 ,  96  cooperate to adjust the position of the seating surface shell  72  according to the weight distribution. The springs  90 ,  92 ,  94 ,  96  of the seating surface shell  72  also minimize the amount of vibration transferred from the vehicle to the passenger.  
         [0027]    As the weight of the passenger is applied to the backrest shell  100 , the springs  112 ,  114 ,  116 ,  118  cooperate to adjust the position of the backrest shell  100  according to the weight distribution. The springs  112 ,  114 ,  116 ,  118  of the backrest shell  100  also minimize the amount of vibration transferred from the vehicle to the passenger.  
         [0028]    The seating surface shell  72  and the backrest shell  100  each provide a unitary structure under the upholstery and padding of the vehicle seat structure to evenly and comfortably support the passenger. Thus, the seating surface portion  70  and the backrest portion  98  cooperate to support the passenger on the vehicle seat structure and isolate the passenger from the vibration of the vehicle.  
         [0029]    [0029]FIG. 6 illustrates a third embodiment of the invention wherein a seating surface shell  120  is formed by using a steel wire frame  122 . Individual rows or strands of the wire frame  122  are held in a desired location by couplings  124 . The couplings  124  in the embodiment shown are produced from plastic. However, it is understood that other conventional materials can be used such as steel in the form of a winding, for example, to hold the wire frame  122  in place.  
         [0030]    In operation, the wire frame provides a flexible shell to provide added comfort to the passenger. The remaining structure and operation of the seating surface portion is substantially the same as that described in FIGS. 4 and 5. The backrest shell portion shown in FIG. 5 can be formed using a steel wire frame as well.  
         [0031]    From the foregoing description, one ordinarily skilled in the art can easily ascertain the essential characteristics of this invention and, without departing from the spirit and scope thereof, can make various changes and modifications to the invention to adapt it to various usages and conditions. For example, additional slots or apertures can be added to the seating surface shell  21  and the backrest shell  34  to change the flexibility as desired.