Abstract:
A plantation window shutter, comprises a frame and a plurality of shutter blades pivotably supported by the frame. The frame has a left stile, a right stile, a bottom rail connected to the left and right stiles and a top rail connected to the left and right stiles. The left stile comprises first and second members joined together, and the right stile third and fourth members joined together. The bottom rail includes first and second end portions sandwiched between the first and second members, and the third and fourth members, respectively. The top rail includes first and second end portions sandwiched between the first and second members, and the third and fourth members, respectively. The left and right stiles include top end portions operably attached to each other. The first and second members have opposing sides including a plurality of mirrored left grooves. The third and fourth members have opposing sides including a plurality of mirrored right grooves, the mirrored left grooves being axially aligned with respective the mirrored right grooves. Each of the shutter blades has a longitudinal pivotal axis and a left pivot and a right pivot aligned along the axis, the left pivot and the right pivot being received in respective one of the mirrored left grooves and the mirrored right grooves.

Description:
RELATED APPLICATION 
       [0001]    This is a nonprovisional application claiming the priority benefit of provisional application Ser. No. 61/216,731, filed May 21, 2009, herein incorporated by reference. 
     
    
     FIELD OF THE INVENTION 
       [0002]    The present invention relates generally to a window shutter and a method of making the same and particularly to an indoor plantation window shutter. 
       BACKGROUND OF THE INVENTION 
       [0003]    Plantation window shutters are currently built by hand by cutting several extruded lengths of plastic material or pre-machined profiles of wood. Manufacturers of window shutters use a variety of wood working hand tools, complex formulas and highly trained expensive craftsmen. The present invention provides additional ways for manufacturing plantation window shutters that reduce costs, improve quality, and reduce dramatically the time it takes to build them. 
       SUMMARY OF THE INVENTION 
       [0004]    The present invention provides a plantation window shutter, comprising a frame and a plurality of shutter blades pivotably supported by the frame. The frame has a left stile, a right stile, a bottom rail connected to the left and right stiles and a top rail connected to the left and right stiles. The left stile comprises first and second members joined together, and the right stile third and fourth members joined together. The bottom rail includes first and second end portions sandwiched between the first and second members, and the third and fourth members, respectively. The top rail includes first and second end portions sandwiched between the first and second members, and the third and fourth members, respectively. The left and right stiles include top end portions operably attached to each other. The first and second members have opposing sides including a plurality of mirrored left grooves. The third and fourth members have opposing sides including a plurality of mirrored right grooves, the mirrored left grooves being axially aligned with respective the mirrored right grooves. Each of the shutter blades has a longitudinal pivotal axis and a left pivot and a right pivot aligned along the axis, the left pivot and the right pivot being received in respective one of the mirrored left grooves and the mirrored right grooves. 
         [0005]    The present invention also provides a method for making a plantation window shutter, comprising the steps of sending to a remote computer measurements of a window opening in which a window shutter will be installed; providing a sheet material from which components of the window shutter will be cut; providing a CNC router machine for cutting the sheet material; receiving by the CNC router machine from the remote computer a machine file configured for operating the CNC router machine to cut the sheet material to produce the components of the window shutter; and assembling the components. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0006]      FIG. 1  is a front perspective view of window shutter embodying the present invention. 
           [0007]      FIG. 2  is a partial assembly view of  FIG. 1 . 
           [0008]      FIG. 3  is an assembly view of the shutter shown in  FIG. 1 . 
           [0009]      FIG. 4  is a cross-sectional view taken along line  4 - 4  in  FIG. 1 . 
           [0010]      FIG. 5  is a fragmentary assembly view of a shutter blade. 
           [0011]      FIG. 6  is an end view of a pivot taken along line  6 - 6  in  FIG. 5 . 
           [0012]      FIG. 7  is an end view of a pivot showing a spline keyed portion. 
           [0013]      FIGS. 8 and 9  are end views of extruded shutter blades that may be used in the window shutter of the present invention. 
           [0014]      FIG. 10  is a cross-sectional view of a section of the gear rack used in the present invention, showing a keyed axial openings for the gears used in the embodiment of  FIG. 1 . 
           [0015]      FIG. 11  is a cross-sectional view taken along line  11 - 11  in  FIG. 1 . 
           [0016]      FIG. 12  is a cross-sectional view taken along line  12 - 12  in  FIG. 1 . 
           [0017]      FIG. 13  is a cross-sectional view taken along  13 - 13  in  FIG. 1 , showing the shutter blades in the closed position. 
           [0018]      FIG. 14  is similar to  FIG. 13 , showing the shutter blades in the open position. 
           [0019]      FIG. 15  is a cross-sectional view taken along line  15 - 15  in  FIG. 1 . 
           [0020]      FIG. 16  is perspective view of another embodiment of a window shutter embodying the present invention. 
           [0021]      FIG. 17  is a partial assembly view of  FIG. 16 . 
           [0022]      FIG. 18  is a cross-sectional view taken along line  18 - 18  in  FIG. 16 . 
           [0023]      FIG. 19  is a cross-sectional view taken along line  19 - 19  in  FIG. 16 . 
           [0024]      FIG. 20  is a partial cross-sectional of another embodiment of the window shutter shown in  FIG. 16 , showing elliptical-shaped extruded shutter blades. 
           [0025]      FIG. 21  is a schematic perspective view of a CNC router machine used in the present invention. 
           [0026]      FIG. 22  is a functional block diagram of a system used in making the shutter of  FIG. 1 . 
           [0027]      FIG. 23  is a flowchart of a system used in making the shutter of  FIG. 1 . 
           [0028]      FIGS. 24-25  show exemplary input window measurements. 
           [0029]      FIGS. 26(   a )- 26 ( f ) illustrate examples of the various cross-sectional profiles of a frame that may be used with the window shutter of  FIG. 1 . 
           [0030]      FIG. 27  illustrates an example calculation in reducing the size of the shutter of  FIG. 1  to account for the dimensions of a separate frame around the shutter of  FIG. 1 . 
           [0031]      FIG. 28  shows a sheet material with an example of the various cuts made by the CNC router machine on one side of a board to make the components of the window shutter shown in  FIG. 1 . 
           [0032]      FIG. 29  shows the other side of the sheet material of  FIG. 28 , showing the various cuts made the CNC router machine. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0033]    Referring to  FIG. 1 , an indoor window shutter  2  embodying the present invention is disclosed. The shutter  2  has a frame  4  having a left stile  6 , a right stile  8 , a bottom rail  10 , a top rail  12  and a plurality of shutter blades  14  pivotably supported by the frame  4  in a horizontal configuration. The left stile  6  is made of separate longitudinal members  16  and  18  attached together, preferably with glue, screws or other conventional ways. The members  16  and  18  may include matching hinge cutouts or recesses  19 . Similarly, the right stile  8  is made of separate longitudinal members  20  and  22  joined together in the same manner as the members  16  and  18 . Preferably, the member  16  is a mirror image of the member  18 . Similarly, the member  20  is preferably a mirror image of the member  22 . Preferably, all the members  18 - 22  are identical to each other for simplicity in manufacture. The rails  10  and  12  are also identical to each other for ease of manufacture. 
         [0034]    Referring to  FIGS. 2 ,  3  and  4 , the bottom rail  10  and the top rail  12  each have end portions  24  that are sandwiched between the respective end portions  30  of the members  16  and  18 , and members  20  and  22 . Each end portion  24  has an opening  26  that receives a projection  28  on the corresponding end portion  30  of the members  16 ,  18 ,  20  and  22 . Each end portion  24  is further received into a recess  32  in the corresponding end portion  30  of the members  16 - 22 . Although the projections  28  are shown as rectangular in plan view, and the openings  26  are of similar shape and size, the projections  28  can be of a different shape, such as a pair of spaced apart cylindrical projections and the openings  26  a pair of correspondingly sized and spaced holes. The projections and the corresponding openings are preferably configured to hold the rails at right angle to the stiles when the projections are received in the corresponding openings, thereby saving time during the assembly. 
         [0035]    Each shutter blade  14  has left pivot  34  and right pivot  36  rotatably received within left groove  38  and right groove  40  in the corresponding members  16 - 22 . Left grooves  38  in the members  16  and  18  are mirror images of each other (mirrored grooves). A groove  38  in the member  16  and the corresponding opposing groove  38  in the member  18  provide sufficient clearance for the left pivot  34  to rotate therein. Similarly, right grooves  40  in the members  20  and  22  are mirror images of each other (mirrored grooves) and that a groove  40  in the member  20  and the corresponding opposing groove  40  in the member  22  provide sufficient space for the right pivot  36  to rotate therein. It should be understood that the left grooves  38  and the right grooves  40  may be completely provided in the two laterally spaced members, such as the members  16  and  20 , or the members  18  and  22 , thereby obviating the need for providing opposing mirrored grooves in the members  16 - 22 . 
         [0036]    The pivots  34  and  36  are aligned along a longitudinal axis of rotation of the corresponding shutter blade  14 . 
         [0037]    Referring to  FIG. 3 , longitudinal slots  42  are provided in the members  16 - 22 . The slots  42  intersect and are preferably disposed perpendicular to the grooves  38  and  40 . The slot  42  in the member  16  is preferably a mirror image of the slot  42  in the member  18  (mirrored slots). Similarly, the slot  42  in the member  20  is preferably a mirror image of the slot  42  in the member  22  (mirrored slots). A gear rack  44  is slidably disposed within the opposing slots  42  in the members  16  and  18  (see  FIG. 12 ). The rack  44  may also be disposed in the opposing slots  42  in the members  20  and  22 . The slots  42  are longer than the length of the gear rack  44  to allow the gear rack  44  to translate up and down as the shutter blades  14  are turned, as will be explained further below. 
         [0038]    Another slot  46  is disposed in each of the members  16 - 22 . The slots  46  are preferably substantially parallel to the slots  42 . The slot  46  in the member  16  is a mirror image of the slot  46  in the member  18  (mirrored slots). Similarly, the slot  46  in the member  20  is a mirror image of the slot  46  in the member  22  (mirrored slots). A stiffener  48  is received within the corresponding pair of mirrore  46  (see  FIG. 11 ). The slots  46  are routed with a very close tolerance to the same size as the stiffener  48  for a pressed fit. The stiffener  48  is preferably in cross-section a square tube, but other cross-sectional shapes may be used, such as U-shaped, I-shaped or V-shaped and made of metal, wood, plastic, fiberglass or other suitable material so as to provide stiffness and strength to the frame  4  and restrict the stiles from twisting and flexing after they are glued together. 
         [0039]    Each of the pivots  34  is associated with a gear  50 , which is in meshing engagement with the gear rack  44 . The gears  50  are fixedly attached to the respective pivot  34  so that when the shutter blade  14  is rotated by hand, the associated gear  50  turns with the associated pivot  34 , which in turn causes the gear rack  44  to translate within the slots  42  that in turn causes the other gears  50  to turn, thereby actuating the other shutter blades  14  to turn in the same direction as the shutter blade being manually turned by hand. 
         [0040]    Referring to  FIG. 5 , each pivot  34  or  36  has a shaft portion  52  and an attachment portion  54 . The attachment portion  54  is receivable with a respective T-shaped slot  56  at each end of each blade  14 . The attachment portion  54  has a T-shaped portion  58  when viewed in cross-section that is receivable within the T-shaped slot  56 , preferably with a friction fit, as shown in  FIG. 6 . The attachment portion  54  also includes a cover portion  60  that overlies and covers the slot  56  when the attachment portion  54  is inserted into the slot  56 . 
         [0041]    The shaft portion  52  of the pivot  34  preferably includes a cylindrical portion  62  and a keyed portion  64 , separated by a flange portion  66 . The cylindrical portion  62  is receivable within the respective grooves  38  and  40 . The keyed portion  64  may include a flat surface  68  that engages a corresponding flat portion  67  (see  FIG. 10 ) in the axial opening in the gear  50  to provide a positive engagement between the pivot  34  and the gear  50 . It should be understood that other standard means of positive attachment between the pivots  34  and the gears  50  may be used, such as a plurality of splines  70 , as shown in  FIG. 7 , that engage with correspondingly shaped opening in the gear  50 . The pivots  34  and  36  are preferably molded from plastic or other suitable material. 
         [0042]    The shutter blade  14  has its longitudinal edges  69  and  71  recessed, so that in the closed position, the shutter blades longitudinal edges overlap one another to provide a substantially flush appearance. The shutter blades  14  may have other profiles, such as elliptical or oblong, as shown in  FIGS. 8 and 9 . 
         [0043]    Referring to  FIGS. 10 and 11 , the gear rack  44  has a U-shaped frame  80  and a linear gear  82  attached to the bottom portion of the frame  80 . The gear  50  has a cylindrical extension  84  on each axial end that rides along a longitudinal slot  86  in each side wall  88  of the frame  80 . The gear  50  meshes with the linear gear  52 . The pivot  34  is shown with a flat portion  68  that keys with a correspondingly shaped opening in the gear  50 . The cylindrical portion  62  rotates within the mirrored grooves  38 . 
         [0044]    The gear rack  44  is made of several sections joined end to end, one section of which is shown in  FIG. 10 . The section has a pair of openings  87  in the side walls  88  that receive a pair of tabs  89  that snap into the openings  87  in the next section, thereby lengthening the gear rack as desired to fit any shutter height. 
         [0045]    Referring to  FIG. 12 , the mirrored slots  42  in the members  20  and  22  are shown empty, since the gear rack  44  is disposed in the other mirrored slots  42  located in the members  16  and  18 . It should be understood that the gear rack  44  may be disposed in the mirrored slots  42  in the members  20  and  22 , instead of in the mirrored slots  42  in the members  16  and  18 , in which case the gears  50  will be attached to the right pivots  36 . 
         [0046]    Referring to  FIGS. 13-15 , the shutter blades  14  are operated from a closed position to an open position and back to the closed position by turning one of the shutter blades  14 . As the actuated shutter blade rotates, its associated gear  50  rotates, thereby causing the gear rack  44  to translate downwardly or upwardly within the slot  42 . Empty spaces  90  and  92  at the top and bottom, respectively, of the gear rack  44 , allow the gear rack  44  to move within the slot  42 . From a closed position, as shown in  FIG. 13 , when one of the shutter blades  14  is rotated counter-clockwise, the associated gear  50  will move counter-clockwise, which in turn will cause the gear rack  44  to move downwardly. The movement of the gear rack  44  will drive the other gears  50  to rotate counter-clockwise, thereby also moving the other shutter blades  14  in the counter-clockwise direction to the open position. Similarly, from the open position shown in  FIG. 14 , when one of the shutter blades  14  is rotated clockwise, the associated gear  50  will rotate clockwise, driving the gear rack  44  to move upwardly, thereby driving all the other gears  50  to rotate clockwise to the closed position. 
         [0047]    Referring to  FIGS. 16 and 17 , another embodiment of a window shutter  94  embodying the present invention is disclosed. The shutter  94  has a frame  96  having a left stile  98 , a right stile  98 , a bottom rail  102 , a top rail  104  and a plurality of shutter blades  106  pivotably supported by the frame  96  in a horizontal configuration. The left stile  98  is made up of separate longitudinal members  108  and  110  attached together, preferably with glue, screws or other conventional ways. The members  108  and  110  may include hinge cutouts or recesses. Similarly, the right stile  96  is made up of separate longitudinal members  112  and  114  joined together in the same manner as the members  108  and  110 . Preferably, the member  108  is a mirror image of the member  110 . Similarly, the member  112  is preferably a mirror image of the member  114 . All the members  108 - 114  are preferably identical to one another for each of manufacture. 
         [0048]    Referring to  FIGS. 17 ,  18  and  19 , the bottom rail  102  and the top rail  104  each have end portions  116  that are sandwiched between the members  108  and  110 , and members  112  and  114 . Each end portion  116  has an opening  118  that receives a projection  120  on the corresponding end portion of the members  108 ,  110 ,  112  and  114 . Each end portion  116  is further received into a recess  122  in the corresponding end portion of the members  108 - 114 . 
         [0049]    Each shutter blade  106  has left and right pivots  124 , which includes shaft portions  125  rotatably received within respective grooves  126  in the corresponding members  108 - 114 . A groove  126  in the member  108  mates with a mirror image groove  126  (mirrored grooves) in the member  110  to provide enough clearance for the shaft portions  125  to rotate therein. It should be understood that the grooves  126  may be completely provided in the two laterally spaced members, such as the members  108  and  112 , or the members  110  and  114 , thereby obviating the need for providing mirrored grooves in the members  108 - 114 . 
         [0050]    The pivots  124  are aligned along a longitudinal axis of rotation of the corresponding shutter blade  106 . 
         [0051]    Referring to  FIGS. 17 ,  18  and  19 , a longitudinal slot  128  is disposed in each of the members  108 - 114  longitudinally of the members. Each slot  128  is a mirror image of the slot in the opposite member. Stiffeners  130  are received with the mirrored slots  128 . The stiffeners  130  are preferably tubular and square in cross-section. They may also be of other suitable cross-sectional shapes, such as U-shaped, I-shaped or V-shaped and made of metal or other suitable material to provide stiffness and strength to the frame  96 . 
         [0052]    Referring to  FIGS. 17 and 18 , the top and bottom shutter blades  106  may be provided with a respective friction washer  132 , preferably rectangular so that it can be held stationary within correspondingly shaped slots while the shutter blades  106  are actuated. Each washer  132  is preferably made of compressible material, such as rubber or elastomeric plastic, and is attached to the shaft portion  125  of the respective pivots  124 . The washer  132  has a friction fit with the shaft portion  125  that allows the respective shutter blade  106  to be pivoted within its range of motion and be held secured to its pivoted position without looseness. Each washer  132  is disposed within respective slots  134  in the respective members  108 - 114 . 
         [0053]    A control rod  136  is hingedly attached to each shutter blade  106  for operating the shutter blades in the open or closed position. Referring to  FIG. 20 , showing the shutter blades with an elliptical profile, the control rod includes staples  138  attached to corresponding staples  140  on the shutter blades. The longitudinal edges of the shutter blades overlap each other in the closed position to completely block the light. 
         [0054]    The window shutter disclosed herein is preferably made from wood or plastic sheet material. The various components of the window shutter are preferably cut from the sheet material using a CNC router machine  142 , such a Camaster Cobra X3, made by Camaster CNC, Inc., Calhoun, Ga. 30701. The process of making the window shutter is similar to that disclosed in copending application Ser. No. 12/752,523, filed Apr. 1, 2010, herein incorporated by reference. 
         [0055]    Referring to  FIG. 21 , the CNC router machine  142  is computer driven and is well know in the art. The machine  142  includes a table surface  144  on which a board  146  to be cut is placed. Alignment or indexing pins  148  hold the board  146  (from which the components of the shutter are cut) in precise location when the board is turned over for cutting on the other side. A router head  150  is movable on the X-Y plane of the table surface  144 . The router head  154  is also movable on the Z-axis, which is perpendicular to the X-Y plane. 
         [0056]    Referring to  FIG. 22 , the router computer  152  is preferably connected to a web server  154  via the internet or other network connections. The web server  154  includes software that generates the programming steps required to drive the router machine  142  to cut the components of the window shutter from the board  146 . Based on the measurements of a window in which the window shutter will be installed, the software in the server  154  will generate the programming steps to drive the router head  150 . The server  154  may be connected to a number of other router machines  142  in various locations. An operator for each machine need not know how to program the machine, since the required programming is downloaded to the router machine computer  152  from the server  154  after the operator provides the window measurements. 
         [0057]    Referring to  FIG. 23 , an example of the process of making and assembling the various components of the window shutter will now be described. An operator inputs at step  156  the numeric measurements of a window in which the shutter will be installed. In addition to a standard rectangular window opening, as shown in  FIG. 24 , where the height and width measurements are input into the system, the window opening may also be a half circle with legs, as shown in  FIG. 25 , where the width, the height- 1  at the top center part of the shutters and height- 2  of the legs of the shutter are measured. If a frame is added to the shutter  2 , a frame type is selected at step  158 . Examples of various frame types are shown in  FIGS. 26(   a )- 26 ( f ). Paint color selection may also be made at step  160 . These inputs are then sent by the operator to the server  154 . 
         [0058]    A program  162  resident within the server  154  or in another computer connected to the server  154  converts the operator&#39;s input at steps  156  and  158  into a G-code file  164 , which is downloaded to the router machine computer  142 . In addition, a drawing file  166  is also generated and downloaded to the router machine computer  142 . The drawing file  142  generates a drawing of the shutter ordered by the operator as a visual check to the operator on what the shutter looks like before the components are cut by the router machine  76 . 
         [0059]    The program  162  includes dimension files  168 , louver sizing files  170 , frame deduction files  172  and G-code generating files  174 . 
         [0060]    The dimension files  168  are a database developed around the sizes of the shutter, for example as shown in  FIGS. 24 and 25 . The database consists of measurements of each shutter type, from the smallest to the largest. Since there is rarely two windows of the same size, based on the measurement provided by the operator at step  156 , the program searches from the list of dimensions that have been loaded into the database covering, for example, a 18 in.×18 in. window up to a 4 ft. high×8 ft. window. Shutter measurements with width dimensions of 18⅛, 18¼, 18⅜, 18½ and so on up, 95½, 95⅝, 95¾, 95⅞, 96 in; and height measurements of 18⅛, 18¼, 18⅜, 18½ and so on up, 47½, 47⅝, 47¾, 47⅞, 48 in are in the database. The shutter measurements that fit the size of the window in which the shutter will be installed is then selected. 
         [0061]    Louver sizing files  170  provide the number of shutter blades appropriate for the size of the window in which the shutter will be installed. As the shutter increases in size, the number of shutter blades also increases. The rectangular shutter has shutter blade width sizes of 2½, 3½ and 4½ in. 
         [0062]    The frame deduction files  102  allow for reductions in measurements provided at step  156  to accommodate a frame if ordered by the operator to be included with the shutter. Examples of frame profiles provided in the program are shown in  FIGS. 26(   a )- 26 ( f ). The measurements of these frame profiles have been loaded into the program. Depending on the frame profile chosen, the program calculates the deductions to shrink the shutter size to accommodate the frame. For example, referring to  FIG. 27 , an L-frame  176  is provided with the shutter  2 . The frame  176  will have a clearance  178  of ⅛ in. around the window frame  180 . Since the frame face has a dimension  182  of 1 in., the shutter will be 2⅜ in. less in height and 2⅜ in. in width than the measurement provided at step  156 . 
         [0063]    The G-code machine file  164  is standard G-code software used for motion control of the cutting tool of the router machine  142  that does the actual work. The G-code machine file  164  includes router tool selection, machine feed rates, tool speeds, tool paths and cutting depths. The G-codes direct the machine actions, such as rapid move; controlled feed move in a straight line or arc; series of controlled feed moves for boring holes; cutting a work piece to a specific dimension; cutting a decorative profile shape to the edge of a work piece; change tool; etc. The generation of G-codes for driving the router machine  142  are well known in the art. The G-codes may be generated using a standard drawing software package, such as AUTOCAD, available from Autodesk, Inc., 111 McInnis Parkway, San Rafael, Calif. 94903 and a standard G-code generating software package, such as ALPHACAM, available from Planit Solutions, Inc., 3800 Palisades Drive, Tuscaloosa, Ala. 35405. For example, referring to  FIGS. 28 and 29 , each figure is generated by the drawing software, which is then converted by the G-code generating software into a G-coded machine file that will drive the router machine  142  to cut the various pieces for the shutter. The G-coded machine file is sent to the router machine computer  152  using standard connections, such as the Internet or other network connections. 
         [0064]    The generation of the G-coded machine file  164  may also be automated by storing a database of G-code files that would be used in cutting any type and size of shutter for which the system is designed. These G-code files include all the necessary machine operations, such as the tool path, tool selection, depth of cut, tool rpm, feed speed, etc. for cutting the parts for any type and size of shutter stored in the system. Data on the dimensions of the ordered shutter, including the number of shutter blades, and any frame deduction generate a drawing file comprising several layered views. Each view is then associated with the appropriate G-code files already stored in the system. All the selected G-code files for all the views are then sent to the router machine computer  152  via the internet or other network connections. 
         [0065]    The cutting process has been described extensively in the copending application Ser. No. 12/752,523. A person of ordinary skill in the art will understand that a similar process is applicable in cutting the various components of the shutter of the present invention. As an example, the various cutting patterns on the board  146 , showing the various components, are shown on one side of the board in  FIG. 28  and on the other side in  FIG. 29 . Note that the stile members are identical and symmetrical about a horizontal centerline so that they can be flipped, turned or otherwise rotated during assembly. The shutter blades  14  are identical to each other. The rails  10  and  12  are also identical to each other. 
         [0066]    The various components of the window shutter disclosed herein are cut from a sheet strip material, made of synthetic material, such as PVC, or wood. The rails may also be made from pre-cut wood or synthetic strip material using a vacuum jig well known in the art. 
         [0067]    While this invention has been described as having preferred design, it is understood that it is capable of further modification, uses and/or adaptations following in general the principle of the invention and including such departures from the present disclosure as come within known or customary practice in the art to which the invention pertains, and as may be applied to the essential features set forth, and fall within the scope of the invention or the limits of the appended claims.