Patent Publication Number: US-9848744-B1

Title: Nested graduated toilet seats

Description:
FIELD OF INVENTION 
     The present invention relates to the field of toilet seats, and more particularly to toilet seat assemblies comprising multiple toilet seats of different sizes. 
     BACKGROUND OF THE INVENTION 
     Standard sized toilet seats are designed to accommodate the body contours of an average adult. They are not well suited to small children, who often must support themselves with their arms to avoid falling through the seat opening. This problem makes the process of toilet training young children all the more difficult. 
     Large and obese adults often have the opposite problem, as their bottom body contours extend well beyond the rim of the standard toilet seat, making it difficult for them to maintain their balance on the seat. 
     Attempts to address these problems have included special toilet seat inserts, such as child seats. But small children usually cannot deploy such inserts without adult assistance, which defeats the goal of enabling the child to use the toilet independently. 
     Another approach has been tiered toilet seats, in which a smaller seat rests on top of a larger seat, and the two seats are cooperatively hinged. But such tiered seat configurations tend to raise the overall height of the seat, making the seating of small children and infirm adults even more difficult. Moreover, the overlapping edges of tiered toilet seats tend to generate lateral movement of the seats when bearing bodily weight, thereby making seating more unstable and less comfortable. 
     The cross-sectional profile of the standard toilet seat is typically flat to slightly convex, which is not optimal for stable seating. Smaller adults and children tend to fall inward on the seat, while larger adults slide outward. Aged and infirm adults often require assistance maintaining their seating on these seats, because they provide no lateral support. 
     (Note: As used in the following descriptions and claims, the terms “outer”, “outward” or “outwardly” refer to the horizontal direction toward the perimeter of the toilet bowl, while the terms “inner”, “inward” or “inwardly” refer to the horizontal direction toward the center of the toilet bowl. The terms “upper”, “upward” or “upwardly” refer to the vertical direction opposite the base of the toilet bowl, while the terms “down”, “downward” or “downwardly” refer to the vertical direction toward the base of the toilet bowl. The term “above” means relatively upward, while the term “below” means relatively downward. The term “top” refers to the most upward, while the term “bottom” refers to the most downward. The term “inclining” means upwardly curving, while the term “declining” means downwardly curving.) 
     SUMMARY OF THE INVENTION 
     The present invention addresses the foregoing problems by providing an assembly of cooperatively hinged nested toilet seats of sizes downwardly graduated from smaller to larger, from a smallest top seat to a largest bottom first seat. Each of the relatively smaller seats nests within a declining inner seat contour of a relatively larger seat below it. 
     An extension of the declining inner seat contour of each seat defines a downward seat flange, which is configured to extend within the rim of the toilet bowl when the seat is lowered. The downward seat flange of the largest bottom first seat is configured to engage the inner perimeter of the toilet bowl rim when the seat is lowered, thereby defining a largest first seat opening. The downward seat flange of the next largest second seat above the largest bottom first seat is configured to nest within and engage the inner perimeter of the first seat opening when the seat is lowered, thereby defining a next largest second seat opening. Similarly, each successively smaller third, fourth, fifth, etc., seat has a downward seat flange which is configured, when the seat is lowered, to nest within and engage the inner perimeter of the seat opening defined by the downward seat flange of the seat below it. 
     The cross-sectional profile of each of the nested toilet seats comprises the downward seat flange, which transitions into the declining inner seat contour, which transitions into a middle seat contour, which in turn transitions into an outer seat contour. In the first embodiment of the present invention, the middle seat contours are substantially convex, and the outer seat contours are declining. In the second embodiment of the present invention, the middle seat contours are substantially concave, and the outer seat contours are inclining. 
     The foregoing summarizes the general design features of the present invention. In the following sections, specific embodiments of the present invention will be described in some detail. These specific embodiments are intended to demonstrate the feasibility of implementing the present invention in accordance with the general design features discussed above. Therefore, the detailed descriptions of these embodiments are offered for illustrative and exemplary purposes only, and they are not intended to limit the scope either of the foregoing summary description or of the claims which follow. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1A  is a perspective view of the first embodiment of the present invention comprising a three-seat assembly, showing the lid lifted, the bottom seat lowered, and the two upper seats partially lifted, with the toilet in ghost view; 
         FIG. 1B  is a perspective view of first embodiment of the present invention, showing the lid lifted and all three seats lowered, with the toilet in ghost view; 
         FIG. 2  is a cross-section view of the three seats depicted in  FIG. 1B , taken along the line A-A, with the toilet bowl rim in ghost view; 
         FIG. 3  is a perspective view of the second embodiment of the present invention, showing the lid lifted and all three seats lowered, with the toilet in ghost view; 
         FIG. 4  is a cross-section view of the three seats depicted in  FIG. 3 , taken along the line B-B, with the toilet bowl rim in ghost view; 
         FIG. 5A  is a perspective view of a toilet seat according to the second embodiment of the present invention; 
         FIG. 5B  is a side profile view of the second embodiment of the present invention, comprising a three-seat assembly, showing the lid and all three seats lowered, with the toilet in ghost view; and 
         FIG. 6  is a detail cutaway rear view of an exemplary composite hinge for the present invention. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     Referring the  FIGS. 1A and 1B , the first embodiment of the present invention is an assembly of three toilet seats  10  comprising a largest bottom first seat  11 , a mid-sized second seat  12  above and smaller than the first seat  11 , and a smallest third seat  13 , above and smaller than the second seat  12 . The assembly is cooperatively hinged  14 , so that each of the seats  11   12   13  and the seat lid  15  can be independently raised and lowered.  FIG. 3  depicts the equivalent structures for the second embodiment of the present invention. 
     As best seen in  FIGS. 1B and 2 , for the first embodiment, and in  FIGS. 3 and 4  for the second embodiment, each of the relatively smaller seats nests within a declining inner seat contour of the larger seat below it. Therefore, as shown in  FIGS. 2 and 4 , the mid-sized second seat  12  nests within the declining inner seat contour of the largest first seat  16 , while the smallest third seat  13  nests within the declining inner seat contour of the mid-sized second seat  17 . The declining inner seat contour of the smallest third seat  18  rests atop the declining inner seat contour of the mid-sized second seat  17 . 
     Referring again to  FIGS. 2 and 4 , an extension of the declining inner seat contour of each seat defines a downward seat flange, which is configured to extend within the toilet bowl rim  19  when the seat is lowered. The downward seat flange of the largest first seat  20 , when lowered, engages the inner perimeter of the toilet bowl rim  19 , thereby defining a largest first seat opening  23 . The downward seat flange of the mid-sized second seat  21 , when lowered, engages the inner perimeter of the first seat opening  23  thereby defining a mid-sized second seat opening  24 . The downward seat flange of the smallest third seat  22 , when lowered, engages the inner perimeter of the second seat opening  24 , thereby defining a smallest third seat opening  25 . 
     As depicted in  FIGS. 2 and 4 , the cross-sectional profile of each of the nested toilet seats comprises the downward seat flange (for the first seat  20 , second seat  21 , third seat  22 ), which transitions into the declining inner seat contour (for the first seat  16 , second seat  17 , third seat  18 ), which transitions into a middle seat contour (for the first seat  26 , second seat  27 , third seat  28 ), which in turn transitions into an outer seat contour (for the first seat  29 , second seat  30 , third seat  31 ). In the first embodiment, as shown in  FIG. 2 , the middle seats contours ( 26 ,  27  and  28 ) are substantially convex, and the outer seat contours ( 29 ,  30  and  31 ) are declining. In the second embodiment, as shown in  FIG. 4 , the middle seat contours ( 26 ,  27  and  28 ) are substantially concave, and the outer seat contours ( 29 ,  30  and  31 ) are inclining. 
     As depicted in  FIG. 5A , the three seats of the second embodiment have the shape of a “tractor seat”  11 , with a substantially concave inner contours  26 , inclining outer contours  29  in the back and sides of the seat, and two declining limb contours  32  in the front of the seat to accommodate the user&#39;s legs.  FIG. 5B  shows in profile the declining limb contours for the first seat  32 , for the second seat  33  and for the third seat  34 . 
       FIG. 6  depicts an exemplary cooperative hinge structure  14  for the first embodiment, showing rotary connections to a common hinge rod  35  for the seat lid  36 , the third seat  37 , the second seat  38 , and the first seat  39 . The hinge structure for the second embodiment would be the same. 
     Although the preferred embodiment of the present invention has been disclosed for illustrative purposes, those skilled in the art will appreciate that many additions, modifications and substitutions are possible, without departing from the scope and spirit of the present invention as defined by the accompanying claims.