Abstract:
A method of forming architectural trim from cellular polyvinylchloride. The process employs manufacturing dimensionalized cellular PVC architectural components from sheet goods that can achieve both linear and radius shapes without using heat bending techniques. The process strengthens the cellular PVC giving it more structural integrity than other products made strictly of cellular PVC. These techniques enable the manufacture of components with tighter tolerances than traditional heat bending techniques which distort the size and shape of the material which make accurate and precise assembly difficult.

Description:
FIELD OF THE INVENTION 
       [0001]    The invention is directed to the field of architecture and in particular to a method of forming architectural trim components from cellular polyvinylchloride or the like material. 
       BACKGROUND OF THE INVENTION 
       [0002]    Architectural trim components are traditionally constructed from wood. Unfortunately, wood is susceptible to decay, and the most common wood decay is dry rot. Dry rot is caused by certain fungi which grow when sufficient moisture is present allowing the fungi to grow and digest the wood, causing the wood to shrink, show a brown discoloration, and crack into pieces. There are many species of fungi that can cause dry rot. For instance, fungus such as serpula lacrymans, armillaria, or lignicolous can cause dry rot wood decay. Some fungi secrete an enzyme that breaks down cellulose in wood which can also lead to discoloration and cracking known as soft rot. These include fungus such as chaetomium, ceratocystis and kretzschmaria deusta fungi. White rot fungi, common in hardwoods used outdoors, breaks down lignin in wood, leaving lighter colored cellulose behind. 
         [0003]    Plastics, including composites made of plastic and wood, have been recognized as a substitute for architectural trim structures. Plastic has weather resistant qualities, can be treated to resist ultraviolet radiation, and has a surface porosity that accepts painting. However, simply substituting plastic for a wood trim structure is not as desirable since plastic possesses poor structural capabilities. Further, a large chunk of plastic creates both a weight and a cost disadvantage. And while plastic may be a beneficial substitute for small trim components, the trend has been to develop lighter, stronger, and more durable products. 
         [0004]    Heating plastic to form curves and bends is well known, but includes the inherent problems caused by the heat changing the structure of the plastic. Fiber reinforced thermoset plastics, such as fiberglass, also provide desirable weather resistant performance qualities but lack the look and feel of traditional wood trim components. Further, fiber reinforced plastics are difficult to shape, modify, or otherwise work with in the field. 
         [0005]    What is lacking in the art are architectural trim components, and the method of constructing them, that can substitute for wood architectural trim components. The components should be constructed of plastic, or a composite of plastic and wood. A preferable material is cellular polyvinylchloride or the like material to produce trim components that are light weight, fast and easy to manufacture, easy to mount, and are weather resistant. 
       SUMMARY OF THE INVENTION 
       [0006]    Disclosed is a method of forming architectural trim components from a plastic, wood-plastic composite, or similar material such as cellular polyvinylchloride (“PVC”), and the product produced by the method. The method comprises the steps of: drawing left, right and front trim members of an architectural trim design on a CAD system using guidelines and machining layers, verifying all tool paths and tolling is correct, importing the CAD drawing into AlphaCAM, and applying machining styles to layers. The output from the AlphaCAM is in NC code and directed to a CNC router. The CNC router is operated to form individual trim members that are assembled using an accelerated PVC adhesive, or similar adhesive. A reactive resin system, filled or unfilled, is then used to fill in spaces or gaps between assembled components. Exposed reactive resin is sanded and the architectural trim component is then primed for painting. The architectural trim can be painted before or after installation, providing a weather resistant product having superior properties to conventional wood. 
         [0007]    The process employs manufacturing dimensionalized cellular PVC architectural trim components from plastic sheets to produce both linear and radius shapes without using heat bending techniques, thus preventing the compromised structural integrity associated with such techniques. In place of the structural weakening of the plastic caused during heating, the instant process strengthens the structure made from cellular PVC by giving it a greater structural integrity than conventional products made strictly of cellular PVC. The disclosed technique enables the manufacture of trim components with tighter tolerances than through traditional heat bending techniques by eliminating structural distortion. 
         [0008]    An objective of the invention is to provide a process wherein architectural trim components of varying designs and sizes can go from a design stage to manufacturing in a matter of minutes. 
         [0009]    Another objective of the invention is to provide a method of creating architectural components that can be repeated quickly and accurately. 
         [0010]    Still another objective of the invention is to provide architectural trim components that can be manufactured using materials and techniques that create a product that will not rot, crack, warp, and is weather resistant. 
         [0011]    Yet still another objective of the invention is to provide an architectural trim that is hollow making it lighter and easier to install versus wood or solid plastic trim. 
         [0012]    Another objective of the invention is to provide an architectural trim product that looks the same as traditional architectural trim made from wood, yet eliminates all the problems associated with wood. 
         [0013]    Yet still another objective of the invention is to provide an architectural trim product that requires minimal maintenance in even the harshest of climates. 
         [0014]    Still another objective of the invention is to provide a process that allows manufacturing of cellular PVC components to create an unlimited combination of shapes and sizes from sheet goods of varying thicknesses. 
         [0015]    Other objectives and further advantages and benefits associated with this invention will be apparent to those skilled in the art from the description, examples and claims which follow. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0016]      FIG. 1  is a top view of the frontal component; 
           [0017]      FIG. 2  is a side view of the frontal component; 
           [0018]      FIG. 3  is a cross sectional view of the frontal component assembled to the side component; 
           [0019]      FIG. 4  is a perspective view of the left side component; 
           [0020]      FIG. 5  is a perspective view of the frontal component; 
           [0021]      FIG. 6  is a perspective view of the right side component; 
           [0022]      FIG. 7  is a pictorial of a mounting structure; 
           [0023]      FIG. 8  is a pictorial of an architectural trim installation; 
           [0024]      FIG. 9  is another pictorial of an architectural trim installation; 
           [0025]      FIG. 10  is perspective view of two pieces of architectural trim attached together; 
           [0026]      FIG. 11  is an exploded view of the two pieces of architectural trim; 
           [0027]      FIG. 12  is a perspective view of the attachment of two components of an architectural trim component; and 
           [0028]      FIG. 13  is a perspective view of an alternative attachment of two components of an architectural trim component. 
       
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT 
       [0029]    Referring to the Figures in general, disclosed is an example of the invention used for architectural trim from cellular polyvinylchloride (“PVC”). One architectural trim component  50  disclosed in the  FIGS. 1-6 and 10-11 , is referred to as the Applicant&#39;s Outlooker design which is a decorative trim component placed beneath a soffit  60  commonly used in early construction and now used to assimilate early construction techniques and appearance. The method of manufacturing such decorative trim components employs a CAD software program for drawing the architectural trim component design, which is then cut from a PVC sheet. By way of example, the Applicant&#39;s Outlooker design shown in  FIGS. 1-6  has a left side component  10 , a right side component  12  forming a mirror image of the left side component  10 , and a frontal component  14 . The left side component  10  having a substantially uniform wall thickness and is further defined by a rear edge  16  and a front contoured edge  18 . Similarly the right side component  12  has a substantially uniform wall thickness and the design is defined by a rear edge  20  and a front contoured edge  22 . The frontal component  14  is rectangular shape having a thickness with a first side edge  24  having a reciprocal angular shape to the front contoured edge  18  of the left side component  10  and a second side edge  26  having a reciprocal angular shape to the front contoured edge  22  of the right side component  12 . 
         [0030]    The CAD drawing of the frontal component  14  is imported into a CAD/CAM program such as ALPHACAM of One Water Ridge Plaza, Charlotte, N.C. 28217, having a programmed algorithm for applying machining styles to layers along the length of the frontal component  14 . In particular the ALPHACAM output in numerical control code for operating a CNC router for cutting the trim shapes from a plastic sheet and positioning guidelines, machine lines  30 , and layers  32  along the length of the frontal component  14  wherein a CNC router forms the individual trim components. To allow for curvatures, the machine lines  30  along section A cut into and decrease the thickness along section A of the frontal component  14 , allowing the frontal component  14  to bend conjugate to front contoured edges  18  and  22 . In  FIG. 3 , section A illustrates a concave positioning of the frontal component  14  and machine lines  30  along section B illustrates a convex positioning. In one method, these machine lines  30  are v-shaped cuts into the inner face  28  of the frontal component  14 , where decreasing the distance between cuts and increasing the depth of the cuts allows for a smaller curvature radius. This process allows the cellular PVC to bend along a contoured edge without the decrease in structural integrity associated with the heating and bending of plastics. 
         [0031]    The frontal component  14  is assembled with the left and right trim components  10 ,  12  wherein the frontal component  14  bends conjugate to the reciprocal front contoured edges  18 ,  22  formed on the left and right side of each individual component  10 ,  12 . The components are permanently fastened together using an accelerated PVC adhesive. While proper machining all but eliminates any spacing between components, space that may still exist is permanently filled with a two part epoxy. Once dry, excess epoxy and any uneven corner edge is sanded to form a uniform seamless corner edge, giving the appearance of a single solid piece of trim. The architectural trim can then be primed and painted. Alternatively the architectural trim can be primed, mounted to a building structure, and then painted, or mounted and then primed and painted. 
         [0032]      FIG. 7  illustrates an installation having a top mounting support  40  securable to soffit  60 , and a side mounting support  42  securable to a wall  62  of a building. Preferably the mounting supports  40  and  42  are made out of the similar PVC material; however, since the mounting supports  40  and  42  will fit within the back surface of the architectural trim and are thereby hidden permanently, other suitable materials may be used. The mounting supports  40  and  42  can be secured to the soffit and wall by conventional fasteners  44  such as screws or nails. Additionally, the mounting supports  40  and  42  can be formed as two separate pieces, or as one piece with a machined v-cut allowing for the angled bend. An architectural trim component  51  can be placed over the mounting supports and fastened by screws, nails or the like. The use of PVC mounting material further provides an option of attaching the architectural trim component  51  by adhesive. As seen in  FIG. 8 , architectural trim components  52  can be placed in series along a building soffit  66  and abutting frieze board  68 , giving the appearance of classical architectural.  FIG. 9  shows how multiple pieces of architectural trim can be incorporated into the outer wall of a building, where the architectural trim of the instant invention provides components  50 ,  54 , and a louver trim component  64 . Additionally, as seen in  FIGS. 9-11 , multiple architectural trim components  50 ,  54  can be joined together and affixed to the building exterior. This combination of two architectural trim components  50  and  54  can also be seen in  FIG. 10 , where the components are shown from a rear side angle.  FIG. 11  is an exploded view of  FIG. 10 . Left side component  55 , right side component  56 , front component  57 , and back component  58  of trim component  54  are depicted in this exploded view. 
         [0033]      FIGS. 12-13  show how the pieces of cellular PVC can be adhered together. In  FIG. 12 , a frontal component  14  and a right side component  12  are shown cut at angles so that the mounting surfaces of each meet at a corner of the architectural trim component  50 .  FIG. 13  depicts a top mounting support  40  attached to a right side component  12  so that the mounting support is hidden from view when the architectural trim component  50  is mounted to the building exterior.  FIGS. 12 and 13  are illustrative and not limiting, as other mounting connections can be used to bond the two pieces of cellular PVC. Tongue-and-groove, lock mitre, and curved edges are examples of other connections which can be used to increase the surface area of mounting surface where the two PVC pieces are joined, where an increase in surface area on the mounting surfaces can increase the strength of the bond between the two components. 
         [0034]    The method of forming architectural trim from cellular polyvinylchloride allows for unlimited radius forms wherein the machining technique eliminates the need for heat bending or laminating. While a detailed embodiment of the instant invention directed to Applicant&#39;s Outlook pattern is disclosed herein, it is to be understood that the disclosed embodiments are merely exemplary of the invention, which may be embodied in various forms and include most any radius form. Therefore, specific functional and structural details disclosed herein are not to be interpreted as limiting, but merely as a basis for the claims and as a representation basis for teaching one skilled in the art to variously employ the present invention in virtually any appropriately detailed structure. 
         [0035]    One skilled in the art will readily appreciate that the present invention is well adapted to carry out the objectives and obtain the ends and advantages mentioned, as well as those inherent therein. The embodiments, methods, procedures and techniques described herein are presently representative of the preferred embodiments, are intended to be exemplary and are not intended as limitations on the scope. Changes therein and other uses will occur to those skilled in the art which are encompassed within the spirit of the invention and are defined by the scope of the appended claims. Although the invention has been described in connection with specific preferred embodiments, it should be understood that the invention as claimed should not be unduly limited to such specific embodiments. Indeed, various modifications of the described modes for carrying out the invention which are obvious to those skilled in the art are intended to be within the scope of the following claims.