Patent Document

RELATED APPLICATION 
       [0001]    This application claims priority to U.S. Provisional Application No. 61/413,575, which was filed Nov. 15, 2010. 
     
    
     TECHNICAL FIELD 
       [0002]    This application relates to extruding of plastic material and more specifically to the extrusion of bath surrounds with a living hinge. 
       BACKGROUND OF THE INVENTION 
       [0003]    Typically to extrude bath surrounds or other parts, raw material is fed into a feed hopper which in turn provides a screw that passes from material through a heater. The material is pushed through a die and then may be pushed through coating equipment and extruded towards a trim knife. The cooling material is frequently passed through pull rollers. 
         [0004]    Bath surrounds for tubs or for showers are usually one piece or several pieces. The one piece surrounds typically have two sidewalls and a back wall. Such one piece construction is problematic in that it is sometimes difficult to handle, difficult to get into a bathroom and expensive to ship because of the odd shapes that are not always nestable. They are also subject to damage while being handled. 
         [0005]    To overcome these problems, surrounds may be created with three separate parts or two separate parts. The three part surrounds include a separate sidewall and a separate back portion. These walls can then be easily stacked and packed and shipping is easier as is placing the product into the bathroom for installation. However, many designs require that the corners be mated carefully such that leakage does not occur between or within seams between the sidewalls and the back wall. Also, caulk is usually used to seal the joints so that leakage does not get behind the walls thereof. 
         [0006]    Bathing vessels may be manufactured from a variety of different materials, such as plastic materials. Plastic bathing vessels, however, must meet certain minimum performance requirements. For instance, the American National Standards Institute (ANSI) sets forth minimum physical requirements and testing methods for plastic bathtub and shower units. A bathing vessel that meets the requirements is approved for use in homes, buildings or other structures as a plumbing fixture. 
       SUMMARY OF THE INVENTION 
       [0007]    According to an embodiment disclosed herein, a bathing vessel is made of a sheet of layered materials. A first narrowed portion about which the sheet bends is provided. The bend defines a first wall and a second wall in the sheet. 
         [0008]    According to a further embodiment disclosed herein, a bathing vessel is made of a sheet of layered materials, which include a first layer of polyurethane material, a second layer of polyurethane material attached to the first layer, a third layer of acrylonitrile butadiene styrene (ABS) material attached to the second layer. The sheet has a first narrowed portion about which the sheet bends. The bend defines a first wall and a second wall in the sheet. 
         [0009]    According to a still further embodiment disclosed herein, a method of constructing a bathing vessel includes providing a sheet of layered materials made of a first layer of polyurethane material, a second layer of polyurethane material attached to the first layer, a third layer of acrylonitrile butadiene styrene (ABS) material attached to the second layer. Other steps include creating a first narrowed portion in the layered materials and bending the sheet about the first narrowed portion for shipping or storage. 
         [0010]    These and other features of the present invention can be best understood from the following specification and drawings, the following of which is a brief description. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0011]      FIG. 1  is a prior art version of a tub surround. 
           [0012]      FIG. 2  is a side view of an extrusion die rollers that are used to construct a panel for use in a shower enclosure. 
           [0013]      FIG. 3  is a back view of the extrusion die rollers of  FIG. 2 . 
           [0014]      FIG. 4  is a top or a bottom view of the wall sections of a bath surround after being subjected to the rollers of  FIG. 3 . 
           [0015]      FIG. 5  is a top view of surround in an installed position. 
           [0016]      FIG. 6  is a view of the walls of  FIG. 4  in a shipping position. 
           [0017]      FIG. 7  shows a side view of the structure of the wall sections. 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
       [0018]    Referring to  FIG. 1 , a typical prior art view of a one piece bathing vessel  10  includes a tub  15 , a surround  20  having three pieces sidewall  30 , sidewall  31  and back wall  25  is shown. In this embodiment, the sidewalls  30  and  31  are connected to the back wall  25  at seams  33 . Seam  34  connects the sidewalls  30 ,  31  and the back wall  25  to the tub. Some surrounds known in the prior art are shipped in one piece without seams  33  and without seams  34 . Such 
         [0019]    Referring now to  FIGS. 2 and 3 , material  50  is extruded through extrusion rollers  45  and is pulled after extrusion by pulling rollers  46 , a pair of hinge rollers  50  are impressed into the material  50  to create grooves  55 ,  56  or narrowed portions that become living hinges of a shower surround  20 . The rollers  50  are spaced apart such that the edges of the extruded material, after a cutting process (not shown), become surround walls  30 ,  31  and the area between the rollers  45  becomes the back wall  25 . Though not shown to scale, one of the hinge rollers  50  may be narrower or wider than the other such that the grooves  55 ,  56  may be of different widths. By modifying placement of the hinge rollers  50 , towards or away from each other along a width of the material  50  downstream of the extrusion rollers  45 , the width of the back portion  25  and the width of the side portions  30 ,  31  may be modified. Though two hinge rollers  50  are shown, more or less hinge rollers may be necessary. For instance, if a bathing vessel, such as a shower enclosure only needs two walls (the rest may be glass or a curtain) only one hinge roller is necessary. Similarly, if more bends are required for a more complex surround  20  more hinge rollers  50  may be provided. Furthermore, other types of rollers or presses may be used to create the narrowed portions  55 ,  56 . 
         [0020]    Referring now to  FIG. 4 , a side view of the wall material  50  after it passes through the hinge rollers  50  is shown. The material  50  is a straight section having sidewalls  30 ,  31 , and back wall  25  joined by living hinges  55 ,  56 . The material  50  is ready for shipping and/or storage. 
         [0021]    Referring now to  FIG. 5 , hinge  55  and  56  are bent so that the material  50  may be shipped handled and stored. Hinge  55  is longer (i.e., wider) than hinge  56 . Therefore, hinge  56  is bent to attach or bend wall  31  into close proximity or touching the back wall  25  and longer hinge  55  is then bent to allow wall  30  to be folded over and to be in close proximity or touching wall  31 . The wall surround  20  is then a more efficient configuration to ship, handle and install. 
         [0022]    Referring now to  FIG. 6 , the walls  30 ,  31  and  25  are unbent as if on site so that the walls are in close proximity to each other at the joints  55  and  56  so that a use of caulking may be minimized or eliminated. The walls may be installed on top of the tub  15  or a shower base (not shown) or the like. Note that because of the proximity of the walls  30 ,  31  and  25 , any leakage behind the walls is stopped by the hinges  55 ,  56  from leaking behind surround  20 . Alternatively, if the roller  51  and the rollers  50  are the same width, the sheet may be shipped, stored or handled flat and then bent in situ to create a surround  20 . 
         [0023]    In embodiments, the layer of acrylic material  130   d  is arranged on the first layer of polyurethane material  130   a , the layer of acrylonitrile butadiene styrene (ABS) material  130   c  is arranged between the layer of acrylic material  130   d  and the first layer of polyurethane material  130   a , and the second layer of polyurethane material  130   b  is arranged between the layer of ABS material  130   c  and the first layer of polyurethane material  130   a . In some examples, additional layers may be arranged among the layers  130   a - d . In other examples, the walls  25 ,  30 ,  31  include only the layers  130   a - d  and are free of other layers, materials, adhesives, or the like. The walls  25 ,  30 ,  31  may have thicknesses between 0.20 to 0.30 inches with 0.25 inch preferred. Similarly the hinges  55 ,  56  may be between 0.020 and 0.10 inches with 0.025 preferred. The ratio between the thickness of the walls to the thickness of the hinges is 15-2:1 with a preferable ratio of 10-5:1 and a more preferable ratio of 8.3:1. 
         [0024]    The thicknesses of the individual layers  130   a - d  is not necessarily shown to scale and may vary, depending on the desired wall strength and location in the wall  25 ,  30 ,  31 , for example. In embodiments, the ratio of the thickness of the layer of acrylic material  130   d  to the thickness of the layer of ABS material is no greater than 1, to facilitate meeting strength requirements. 
         [0025]    In embodiments, the first layer of polyurethane material  130   a , the second layer of polyurethane material  130   b , or both, are foamed polyurethane materials. In some examples, the density of the first layer of polyurethane material  130   a  is different than the density of the second layer of polyurethane material  130   b . For instance, the density of the first layer of polyurethane material  130   a  is greater than the density of the second layer of polyurethane material  130   b , to facilitate achievement of a desired degree of strength of the walls  24 . 
         [0026]    In a further example, the second layer of polyurethane material  130   b  is a rigid layer and has a density of 1-10 pounds per cubic foot. The first layer of polyurethane material  30   a  is an elastomeric layer and has a density of about 25-65 pounds per cubic foot though in some examples approximately 55-65 pounds per cubic foot are used. In one example, the density is approximately 62 pounds per cubic foot. 
         [0027]    Although a combination of features is shown in the illustrated examples, not all of them need to be combined to realize the benefits of various embodiments of this disclosure. In other words, a system designed according to an embodiment of this disclosure will not necessarily include all of the features shown in any one of the Figures or all of the portions schematically shown in the Figures. Moreover, selected features of one example embodiment may be combined with selected features of other example embodiments. 
         [0028]    The preceding description is exemplary rather than limiting in nature. Variations and modifications to the disclosed examples may become apparent to those skilled in the art that do not necessarily depart from the essence of this disclosure. The scope of legal protection given to this disclosure can only be determined by studying the following claims.

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