Patent Publication Number: US-2022220798-A1

Title: Door skin stacking

Description:
This application is a continuation of U.S. patent application Ser. No. 16/379,304 filed Apr. 9, 2019, now U.S. Pat. No. 11,293,213, which is a continuation-in-part of U.S. patent application Ser. No. 15/784,306 filed Oct. 16, 2017, the complete disclosure of which is incorporated herein by reference and to which priority is claimed. 
    
    
     FIELD OF THE INVENTION 
     This invention relates door skins, sometimes known as door facings, and in particularly exemplary embodiments of the invention door skins made of cellulosic material and a binder resin. This invention also relates to doors including door skins and a doorframe, and to door skins configured into a stack of door skins to facilitate shipping and handling. 
     BACKGROUND 
     Traditional solid wood doors have become relatively expensive due to raw material costs. A commonplace alternative to traditional solid wood doors in residential and commercial buildings is a door assembly that includes a rectangular doorframe of stiles and rails, and door skins secured to the opposite sides of the doorframe to define a door cavity between the door skins and surrounded by the doorframe. The door skins can be made of, for example, steel, fiberglass composites, cellulosic (e.g., wood) composites such as high-density fiberboard (HDF) and medium density fiberboard (MDF), and other materials. Wood grain can be molded or embossed into the exterior surfaces of the door skins. Further, paneling can be formed in the exterior surfaces of the door skins to give an appearance that simulates solid wood products. The door cavity between the door skins typically yet optionally includes one or more core components. 
     SUMMARY OF THE INVENTION 
     According to an embodiment of the invention, a door skin stack is provided that includes a plurality of door skins, the door skins including at least a first door skin and a second door skin having identical profiles and each including at least one inner panel, an outer body portion surrounding the at least one inner panel, and at least one contoured portion surrounding the at least one panel and interconnecting the at least one panel to the outer body portion, the at least one contoured portion including a substantially V-shaped indent area adjacent to and within the outer body portion, a planar area that is substantially parallel to the outer body portion and is adjacent to and within the substantially V-shaped indent area, and a declining area adjacent to and within the planar area and terminating at the inner panel. 
     Other aspects of the invention, including door skins, assembled doors, stacked door skins, related methods, and the like which constitute part of the invention, will become more apparent upon reading the following detailed description of the exemplary embodiments. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWING(S) 
       The accompanying drawings are incorporated in and constitute a part of the specification. The drawings, together with the general description given above and the detailed description of the exemplary embodiments and methods given below, serve to explain the principles of the invention. In such drawings: 
         FIG. 1  is a cross-sectional view of a door taken along sectional line  1 - 1  of  FIG. 6  according to an embodiment of the invention; 
         FIG. 2  is an enlarged fragmented view of a sectional profile region of the door of  FIG. 1  taken along sectional line  2 - 2  of  FIG. 6 ; 
         FIG. 3  is an enlarged, fragmented, perspective view of a front exterior surface of a door skin illustrating a panel profile according to the invention; 
         FIG. 4  is an enlarged, fragmented, elevational view of the front exterior surface of the door skin taken within box  4  of  FIG. 6 ; 
         FIG. 5  is an enlarged, fragmented, elevational view of a rear exterior surface of the front exterior surface fragmented view of  FIG. 4 ; 
         FIG. 6  is a front elevational view of a door skin according to a first embodiment of the invention; 
         FIG. 7  is a front elevational view of a door skin according to a second embodiment of the invention having a sectional profile region taken along sectional line  2 - 2  of  FIG. 7  that is identical to the sectional profile region of  FIG. 2 ; 
         FIG. 8  is a front elevational view of a door skin according to a third embodiment of the invention having a sectional profile region taken along sectional line  2 - 2  of  FIG. 8  that is identical to the sectional profile region of  FIG. 2 ; 
         FIG. 9  is a front elevational view of a door skin according to a fourth embodiment of the invention having a sectional profile region taken along sectional line  2 - 2  of  FIG. 9  that is identical to the sectional profile region of  FIG. 2 ; 
         FIG. 10  is a front elevational view of a door skin according to a fifth embodiment of the invention having a sectional profile region taken along sectional line  2 - 2  of  FIG. 10  that is identical to the sectional profile region of  FIG. 2 ; 
         FIG. 11  is a front elevational view of a door skin according to a sixth embodiment of the invention having a sectional profile region taken along sectional line  2 - 2  of  FIG. 11  that is identical to the sectional profile region of  FIG. 2 ; 
         FIG. 12  is a front elevational view of a door skin according to a seventh embodiment of the invention having a sectional profile region taken along sectional line  2 - 2  of  FIG. 12  that is identical to the sectional profile region of  FIG. 2 ; 
         FIG. 13  is a front elevational view of a door skin according to an eighth embodiment of the invention having a sectional profile region taken along sectional line  2 - 2  of  FIG. 13  that is identical to the sectional profile region of  FIG. 2 ; 
         FIG. 14  is a front elevational view of a door skin according to a ninth embodiment of the invention having a sectional profile region taken along sectional line  2 - 2  of  FIG. 14  that is identical to the sectional profile region of  FIG. 2 ; 
         FIG. 15  is an enlarged, fragmented, perspective view of a front exterior surface of a door skin having a wood grain appearance; 
         FIG. 16  is an enlarged, fragmented, elevational view of the front exterior surface of the door skin taken within box  16  of  FIG. 18 ; 
         FIG. 17  is an enlarged, fragmented, elevational view of a rear exterior surface of the front exterior surface fragmented view of  FIG. 16 ; 
         FIG. 18  is a front elevational view of a door skin according to a tenth embodiment of the invention; 
         FIG. 19  is a front elevational view of a door skin according to an eleventh embodiment of the invention having a sectional profile region taken along sectional line  2 - 2  of  FIG. 19  that is identical to the sectional profile region of  FIG. 2 ; 
         FIG. 20  is a front elevational view of a door skin according to a twelfth embodiment of the invention having a sectional profile region taken along sectional line  2 - 2  of  FIG. 20  that is identical to the sectional profile region of  FIG. 2 ; 
         FIG. 21  is a front elevational view of a door skin according to a thirteenth embodiment of the invention having a sectional profile region taken along sectional line  2 - 2  of  FIG. 21  that is identical to the sectional profile region of  FIG. 2 ; 
         FIG. 22  is a front elevational view of a door skin according to a fourteenth embodiment of the invention having a sectional profile region taken along sectional line  2 - 2  of  FIG. 22  that is identical to the sectional profile region of  FIG. 2 ; 
         FIG. 23  is a front elevational view of a door skin according to a fifteenth embodiment of the invention having a sectional profile region taken along sectional line  2 - 2  of  FIG. 23  that is identical to the sectional profile region of  FIG. 2 ; 
         FIG. 24  is a front elevational view of a door skin according to a sixteenth embodiment of the invention having a sectional profile region taken along sectional line  2 - 2  of  FIG. 24  that is identical to the sectional profile region of  FIG. 2 ; 
         FIG. 25  is a front elevational view of a door skin according to a seventeenth embodiment of the invention having a sectional profile region taken along sectional line  2 - 2  of  FIG. 25  that is identical to the sectional profile region of  FIG. 2 ; 
         FIG. 26  is a front elevational view of a door skin according to an eighteenth embodiment of the invention having a sectional profile region taken along sectional line  2 - 2  of  FIG. 26  that is identical to the sectional profile region of  FIG. 2 ; 
         FIG. 27  is a cross-sectional view of a first door skin of the door of  FIG. 1  stacked with a second door skin of the door of  FIG. 1 , the door skins having an identical profile; and 
         FIG. 28  is a is an enlarged fragmented view of a sectional profile region of the stacked door skins within the broken-line oval area  28  of  FIG. 27 . 
     
    
    
     DETAILED DESCRIPTION OF THE EXEMPLARY EMBODIMENTS AND EXEMPLARY METHODS 
     Reference will now be made in detail to exemplary embodiments and methods of the invention. It should be noted, however, that the invention in its broader aspects is not necessarily limited to the specific details, representative materials and methods, and illustrative examples shown and described in connection with the exemplary embodiments and methods. 
     Referring to  FIGS. 1-6 , there is illustrated a first embodiment of a single-panel door, generally designated by reference numeral  10 , including a first door skin  11  and a second door skin  14 . The door skins  11  and  14  may be identical with identical profiles, as shown, by molding (e.g., compression molding) the skins  11 ,  14  in the same molding apparatus and from the same materials. The first door skin  11  has a first exterior surface  12  and an opposite first interior surface  13 . Likewise, the second door skin  14  has a second exterior surface  15  and an opposite second interior surface  16 . The first and second exterior surfaces  12  and  15  are opposite or face away from one another. The first and second interior surfaces  13  and  16  face towards one another. Although not shown in  FIGS. 1-6 , the first and second exterior surfaces  12  and  15  may be molded, embossed, or otherwise provided with a surface pattern or texture, such as a wood grain pattern and/or wood tonal areas that replicate the natural background tones of natural wood. The exterior surfaces  12  and  15  may have one or more coatings, which may include, for example, paint, stain, lacquer, and/or a protective finish. A frame  18  positioned about the periphery of the door skins  11  and  14  contacts and is adhered or otherwise secured to the first and second interior surfaces  13  and  16 . Although not shown, a door core may be positioned between the first and second door skins  11  and  14 . 
     The door skins  11  and  14  may be made from wood composite materials such as medium density fiberboard (MDF) or high-density fiberboard (HDF), fiberglass-reinforced polymer materials, metal (e.g., steel), or other materials. Preferably, the door skins  11  and  14  are molded wood composite articles made from a cellulosic mat containing a combination of cellulosic fibers and a natural or synthetic binder, such as a phenol formaldehyde or urea formaldehyde resin. The frame  18  may be made of wood, composite materials, metal, or other materials. The door cavity between the door skins typically yet optionally includes one or more core components (not shown). The core component(s) can be a pre-formed structure or formed in situ, such as by injecting a foam precursor composition into the door cavity and allowing the precursor composition to expand and fill the door cavity with foam. 
     The making of door skins in general and assembling of doors is known in the art, as described for example in U.S. Pat. No. 5,543,234 to Lynch et al. and U.S. Pat. No. 9,657,512. 
     The first and second door skins  11  and  14  of the first illustrated embodiment of  FIGS. 1-6  are each a one-panel skin having an inner panel  20 , an outer body portion or outer skirt  24  surrounding the inner panel  20 , and a contoured portion or ovalo  22  interconnecting and integrally formed as a unitary piece with the inner panel  20  and the outer body portion  24 . When viewed from the exterior side of the door skin  11 , the contoured portion  22  defines a continuous depression extending into the planar portions of the exterior surface  12  toward the door core and around the entire periphery of inner panel  20 . The contoured portion  22  preferably is continuous and has a uniform cross section, best shown in  FIGS. 1 and 2 , about its entire length. 
     As best shown in  FIG. 2 , the contoured portions  22  replicate fine millwork. Each contoured portion  22  includes a substantially V-shaped indent area  26  immediately adjacent to and within or interior relative to the outer body portion  24 , a planar area  28  immediately adjacent to and within the substantially V-shaped indent area  26  that is substantially parallel to and coplanar with the outer body portion  24 , and a declining or tapering area  30  immediately adjacent to and within the planar area  28  that terminates at the inner panel  20 . The declining area  30  has three angled zones  32 ,  34 , and  36  interconnected to one another, with the outer and inner angled zones  32  and  36  declining or tapering at a greater rate than the intermediate angled zone  34  therebetween. Due mostly to the declining or tapering areas  30 , the inner panels  20  of the first and second door skins  11  and  14  are spaced more closely to one another than the outer body portions  24  of the door skins  11  and  14 . 
     As best shown in  FIG. 6 , the single contoured portion  22  of the first embodiment has a continuous and uniform rectangular appearance from a front elevational viewpoint.  FIGS. 7-14  illustrate exemplary embodiments of variations and modifications to the design of the door skins  11  and  14  that may be implemented. The encircling contoured portions  22   a ,  22   b ,  22   c ,  22   d ,  22   e ,  22   f ,  22   g , and  22   h  of the door skins  10   a ,  10   b ,  10   c ,  10   d ,  10   e ,  10   f ,  10   g , and  10   h  of each embodiment of  FIGS. 7-14  have the same cross-sectional profile region as the contoured portion  22  of door skin  10  shown in  FIG. 2 . 
     Referring now to  FIGS. 27 and 28 , the first door skin  11  is shown stacked with the second door skin  14 , which has an identical profile to the first door skin  11 . The second door skin  14  is inverted relative to its orientation in  FIGS. 1 and 2 . The description of the contours  22  above is incorporated herein by reference. For convenience, the suffix “a” is added to reference numerals associated with the first door skin  11  and the suffix “b” is added to reference numerals associated with the second door skin  14 . The first door skin  11  is shown stacked on the second door skin  14 , although it should be understood that the second door skin  14  may be stacked on the first door skin  11  in a like manner. 
     The first door skin  11  includes an outer body portion  24   a  with the interior surface  13  above and spaced from the exterior surface  15  of an outer body portion  24   b  of the second door skin  14 . The first door skin  11  further includes a substantially V-shaped indent area  26   a  immediately adjacent to and within or interior relative to the outer body portion  24   a . Likewise, the second door skin  14  includes a substantially V-shaped indent area  26   b  immediately adjacent to and within or interior relative to the outer body portion  24   b . The interior surface  13  of the indent area  26   a  of the first door skin  11  is above and in direct contact with the exterior surface  15  of the indent area  26   b  of the second door skin  14 . The indent area  26   a  nests on the indent area  26   b  to space the interior surface  13  of the outer body portion  24   a  of the first door skin  11  from the interior surface  15  of the outer body portion  24   b  of the second door skin  14 . 
     The first door skin  11  further includes a planar area  28   a  immediately adjacent to and within the substantially V-shaped indent area  26   a . The planar area  28   a  is substantially parallel to and coplanar with the outer body portion  24   a . The second door skin  14  further includes a planar area  28   b  immediately adjacent to and within the substantially V-shaped indent area  26   b . The planar area  28   b  is substantially parallel to and coplanar with the outer body portion  24   b . The interior surface  13  of the planar area  28   a  is above and spaced from the exterior surface  15  of the planar area  28   b  of the second door skin  14  while the skins  11  and  14  are stacked. 
     A declining or tapering area, generally designated by reference numeral  30   a , of the first door skin  11  is immediately adjacent to and within the planar area  28   a . The declining area  30   a  has three angled zones  32   a ,  34   a , and  36   a  interconnected to one another, with the outer and inner angled zones  32   a  and  36   a  declining or tapering at a greater rate than the intermediate angled zone  34   a  therebetween. A declining or tapering area  30   b  of the second door skin  14  is immediately adjacent to and within the planar area  28   b . The declining area  30   b  has three angled zones  32   b ,  34   b , and  36   b  interconnected to one another, with the outer and inner angled zones  32   b  and  36   b  declining or tapering at a greater rate than the intermediate angled zone  34   b  therebetween. The interior surface  13  of the angled zones  32   a  and  36   a  are above and in direct contact with the exterior surface  14  of the angled zones  32   b  and  36   b , respectively. The angled zones  32   a  and  36   a  nest on the angled zones  32   b  and  36   b . The interior surface  13  of the angled zone  34   a  is above and spaced from the exterior surface  14  of the angled zone  34   b.    
     An inner panel  20   a  is located at an opposite end of the declining or tapering area  30   a . Similarly, an inner panel  20   b  is located at an opposite end of the declining or tapering area  30   b . The interior surface  13  of the inner panel  20   a  is above and spaced from the exterior surface  14  of the inner panel  20   b.    
     Although  FIGS. 27 and 28  show two stacked door skins  11  and  14 , it should be understood that three, four, five, six, or more (e.g., one hundred) door skins may be stacked with one another. Further, the different door designs described below, including in connection with  FIGS. 7-26 , may be stacked in a similar manner. 
     The nestable/stackable door skins  11 ,  14  allow for stacking of multiple door skins with one another, such as for shipping and storage, without the need for spacers. Preferably, nesting contact is limited to the relatively narrow angular portions  26   a / 26   b ,  32   a / 32   b , and  36   a / 36   b , so that surface texture of the exterior surface of the larger area inner panels  20   a / 20   b  and the outer body portions  24   a / 24   b  are not adversely affected, such as by the movement of door skins  11  and  14  relative to one another during processing and shipping. 
     Also, the first and second door skins  11  and  14  may have thicknesses that vary over their lengths. For example, as best shown in  FIG. 28 , the first door skin  11  has a reduced thickness at the intersection of the outer body portion  24   a  and the substantially V-shaped indent area  26   a , at the intersection of the substantially V-shaped indent area  26   a  and the planar area  28   a , at the intersection of the planar area  28   a  and the angled zone  32   a , and at the intersection of the angled zones  34   a  and  36   a . These reduced-thickness zones may be established by providing recesses at the intersections, particularly at the interior surfaces  13  and  16  of the door skins  11  and  14 . For example, for compression molded door skins, the recesses may be made by shaping the mold die surfaces to control caliper (or mold cavity thickness) so that the caliper is reduced at the aforementioned intersections. The second door skin  14  has similar reduced thickness zones at its intersections  24   b / 26   b ,  26   b / 28   b ,  28   b / 32   b , and  34   b / 36   b . Those skilled in the art recognize that as thickness decreases, density increases and thus control of thickness must take into account the density of the door skins  11 ,  14 . The external surface of each door skin  11 ,  14  should be sufficiently hard (dense) in order to withstand impact, such as from contact with an article, etc. 
     While  FIG. 6  illustrates an embodiment of a door skin  11  with one inner panel  20 , the number of inner panels  20  may be varied. For example, the door skins  11  and  14  may have two inner panels with two contoured portions (e.g., the embodiments of  FIGS. 7-9 ), three inner panels with three contoured portions (e.g., the embodiments of  FIGS. 10-12 ), four inner panels with four contoured portions (e.g., the embodiment of  FIG. 13 ), five inner panels with five contoured portions (e.g., the embodiment of  FIG. 14 ), or more inner panels and associated contoured portions. The inner panels  20  may be arranged in vertically stacked configurations (e.g., the inner panels of the embodiments of  FIGS. 7-9, 11, 12, and 14 ), side-by-side juxtaposed configurations, or a combination of vertically stacked and side-by-side juxtaposed configurations (e.g., the inner panels of the embodiments of  FIGS. 10 and 13 ). The perimeters of the inner panels may establish other shapes, such as other polygons, circles, ovals, etc. The inner panels may have the same shapes (e.g., the inner panels of  FIGS. 12 and 14 ) or different shapes (e.g., the inner panels of  FIGS. 7-11 and 13 ) and/or dimensions from one another. 
     The door skins  11  and  14  may have an identical or different arrangement of inner panels and other surface features (e.g., embossed wood grain) on their respective exterior surfaces  12  and  15 .  FIGS. 15-18  illustrates a door  10 ′ that is identical to door  10  of  FIGS. 3-6 , except for the addition of a wood grain pattern in the exterior surface of the door skins. The door  10 ′ includes a first door skin  11 ′ and a second door skin (not shown in  FIGS. 15-18  but identical to the second door skin  14  but with a wood grain pattern added). The first door skin  11 ′ has a first exterior surface and an opposite first interior surface. Likewise, the second door skin has a second exterior surface and an opposite second interior surface. The first and second door skins of the embodiment of  FIGS. 15-18  are each a one-panel skin having an inner panel  20 ′, an outer body portion or outer skirt  24 ′ surrounding the inner panel  20 ′, and a contoured portion or ovalo  22 ′ interconnecting and integrally formed as a unitary piece with the inner panel  20 ′ and the outer body portion  24 ′. When viewed from the exterior side of the door skin  11 ′, the contoured portion  22 ′ defines a continuous depression extending into the planar portions of the exterior surface toward the door core. The contoured portion  22 ′ has a sectional profile taken along sectional lines  1 - 1  and  2 - 2  of  FIG. 18  that is identical to the sectional profile of  FIGS. 1 and 2 . 
       FIGS. 19-26  illustrate doors  10   a ′,  10   b ′,  10   c ′,  10   d ′,  10   e ′,  10   f ′,  10   g ′, and  10   h ′, respectively, having door skins including panel arrangements with encircling contoured portions  22   a ′,  22   b ′,  22   c ′,  22   d ′,  22   e ′,  22   f ′,  22   g ′, and  22   h ′, that are identical to  FIGS. 7-14 , respectively, except that the exterior surfaces of the door skin of the doors  10   a ′,  10   b ′,  10   c ′,  10   d ′,  10   e ′,  10   f ′,  10   g ′, and  10   h ′ of  FIGS. 19-26  are provided with wood grain patterns. Those skilled in the art will understand that the wood grain pattern may be applied or formed also with the profile portions  22   a ′,  22   b ′,  22   c ′,  22   d ′,  22   e ′,  22   f ′,  22   g ′, and  22   h′.    
     The door skins with woodgrain exterior surfaces of  FIGS. 15-26  can be stacked and nested with one another in the same manner described above in connection with  FIGS. 27 and 28 . The woodgrain embossing or molding does not adversely affect nesting. 
     The foregoing detailed description of the certain exemplary embodiments has been provided for the purpose of explaining the principles of the invention and its practical application, thereby enabling others skilled in the art to understand the invention for various embodiments and with various modifications as are suited to the particular use contemplated. This description is not necessarily intended to be exhaustive or to necessarily limit the invention to the precise embodiments disclosed.