Patent Publication Number: US-11648856-B2

Title: Performance seat cushion

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application claims the benefit of the filing date of provisional application 63/107,912, titled, Performance Seat Cushion, filed Oct. 30, 2020. 
    
    
     BACKGROUND 
     Field 
     This disclosure relates generally to a seat cushion and, more particularly, to a performance seat cushion for a seat in a high-performance off-road racing vehicle, where the seat cushion includes a thin top polyurethane layer and a thick bottom energy absorbing foam layer. 
     Discussion of the Related Art 
     Off-road racing is a form of motorsports that employs specially-modified high performance vehicles, such as trucks, cars, buggies, etc. Some forms of off-road racing include tracks having jumps, washboard runs, etc. where the vehicle often goes airborne at significant heights. Often times when the vehicle lands, the suspension bottoms out creating significant downward forces on the driver that may be absorbed by the drivers spine, possibly causing spinal and other injuries. 
     The seats, sometimes referred to as racing shells, used in off-road racing vehicles are usually a one-piece molded fiberglass or carbon fiber part that is wrapped in an upholstery, where foam pieces may be provided between the fiberglass and upholstery at desirable locations. The seat is configured to conform to the driver and hold him/her as stationary as possible in response to lateral forces on the vehicle during the racing. The bottom of the seat often includes a seat cushion that provides some level of comfort and protection from Z-direction impacts. High energy impact foams are known to be used in the art for these seat cushions, such as those available from BSCI Energy Impact Systems, Inc. of Mooresville, N.C., USA. However, injuries still periodically occur, and thus those and other seat cushions can be improved to better protect the driver from large Z-direction impacts on the vehicle. 
     SUMMARY 
     The following discussion discloses and describes a seat cushion for a seat in a high performance off-road racing vehicle. The seat cushion includes two foam layers, namely, a top thin foam layer and a bottom thick energy absorbing foam layer that are secured together, where the combination of the layers are capable of absorbing high energy Z-direction forces. In one non-limiting embodiment, the top layer is a methylenediphenyl isocyanate (MDI) polyurethane foam and is 12 mm thick, and the bottom layer is an open-cell energy absorbing urethane foam and is 38 mm thick. 
     Additional features of the disclosure will become apparent from the following description and appended claims, taken in conjunction with the accompanying drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG.  1    is an isometric view of a vehicle seat including an energy absorbing seat cushion; 
         FIG.  2    is an isometric view of the seat cushion separated from the seat shown in  FIG.  1   ; and 
         FIG.  3    is a cross-sectional view of the seat cushion separated from the seat shown in  FIG.  1   . 
     
    
    
     DETAILED DESCRIPTION OF THE EMBODIMENTS 
     The following discussion of the embodiments of the disclosure directed to a seat cushion for a seat in a high performance off-road racing vehicle, where the seat cushion includes a thin top polyurethane layer and a thick bottom energy absorbing foam layer, is merely exemplary in nature, and is in no way intended to limit the disclosure or its applications or uses. For example, as discussed, the seat cushion has particular application for a seat for a high performance off-road racing vehicle. However, as will be appreciated by those skilled in the art, the seat cushion may have application for other seats. 
       FIG.  1    is an isometric view of a vehicle seat  10  of the type that would be provided in a vehicle used for off-road racing. The seat  10  generally has an ergonomic configuration that at least somewhat conforms to the driver&#39;s body and holds the driver in the seat  10  in response to side-ways forces. The seat  10  is generally a one-piece molded fiberglass or carbon fiber part that is wrapped in an upholstery layer  12 , where foam pieces of various thicknesses may be provided between the fiberglass and the upholstery layer  12  at desirable locations. The seat  10  includes a seat back  14  having a head rest  16 , side panels  18  and  20  and a seat bottom  24  having a seat cushion  26  and a thigh support  28 . 
     As will be discussed in detail below, the seat cushion  26  is designed to absorb downward forces to provide protection for the driver from large Z-direction impacts.  FIG.  2    is an isometric view and  FIG.  3    is a cross-sectional view of the seat cushion  26  separated from the seat  10 . The seat cushion  26  has a general square configuration with rounded corners  34  at a front edge  36  proximate the thigh support  28 . In one non-limiting embodiment, the front edge  36  is 335 mm wide, a rear edge  38  is 350 mm wide and a side edge  40  is 315 mm deep. The seat cushion  26  includes two foam layers, namely, a top thin foam layer  44  and a bottom thick energy absorbing foam layer  46  that are secured together, such as by a suitable glue, where the combination of the layers  44  and  46  is capable of absorbing high energy Z-direction forces. In one non-limiting embodiment, the top foam layer  44  is a methylenediphenyl isocyanate (MDI) polyurethane foam and is 12 mm thick, and the bottom foam layer  46  is an open-cell energy absorbing urethane foam, such as that available from BSCI Energy Impact Systems, Inc. of Mooresville, N.C., USA, and is 38 mm thick, so that the seat cushion  26  has an overall thickness of 50 mm. 
     The foregoing discussion discloses and describes merely exemplary embodiments of the present disclosure. One skilled in the art will readily recognize from such discussion and from the accompanying drawings and claims that various changes, modifications and variations can be made therein without departing from the spirit and scope of the disclosure as defined in the following claims.