A panel system includes elongated panels coupled together at a seam portion with respective interlocking portions at corresponding vertical ends to provide a substantially planar surface. In siding panel systems, joined siding panels are provided in vertically arranged rows that further couple together along adjacent horizontal edges of the respective rows of siding panels.

CROSS REFERENCE TO RELATED APPLICATIONS 
       [0001]    The present application claims the benefit of priority of U.S. Provisional Application No. 61/650,102 filed on May 22, 2012, and is a Continuation-in-part of U.S. patent application Ser. No. 13/847,087 filed on Mar. 19, 2013, which is a Continuation of U.S. patent app. Ser. No. 12/750,065 filed on Mar. 30, 2010, now U.S. Pat. No. 8,402,707, which claims the benefit of U.S. Provisional Application No. 61/299,383 filed on Jan. 29, 2010, all of which are incorporated herein by reference. 
     
    
     BACKGROUND OF THE INVENTION 
       [0002]    1. Field of the Invention 
         [0003]    The present invention relates to panel systems, such as generally flat sections used in building, construction and other applications, including in walls, siding, flooring, tiling, shelving, furniture and like. In non-limiting embodiments the present invention provides a system of interlocking siding panels and a method of making interlocking siding panels. 
         [0004]    2. Description of Related Art 
         [0005]    Vinyl and metal siding panels, such as those used to cover the exterior of a building, generally are formed as single lap panels that extend horizontally across the building. In cases where a single panel is not long enough to extend across an entire surface of a building, multiple panels may be positioned horizontally adjacent to one another. Horizontally adjacent siding panels may overlap one another, such as when the siding panels are thin or hollow, or may be fastened with their ends in an abutting arrangement such as with a bracket or shim. 
         [0006]    Once installed, the siding panels may tend to expand or contract horizontally as the ambient temperature changes. This expansion and contraction may cause irregularities in the seam section between two adjacent panels. For example, if adjacent abutting panels expand, the ends of the adjacent panels may expand toward each other, causing them to deflect away from the building at the seam section. If adjacent abutting panels contract, the ends of the panels may draw away from each other, resulting in a gap at the seam section. The gapping created by expansion or contraction of the siding panels may leave openings that can be unsightly, and leave the siding and building surface susceptible to damage from the elements. 
         [0007]    In siding panel assemblies having overlapping end portions, the overlapping portion typically is left unfastened, so that the individual panels may expand and contract without causing bulging or gapping. However, the overlapping region leaves an undesirable visible seam. In addition, the gap between the two overlapping sections allows water, air, and insects to pass which may cause damage to the siding panels or the underlying building surface. Furthermore, where the overlapping region is unfastened, the ends of the siding panels can separate, further exacerbating these issues. 
         [0008]    In siding panel assemblies having abutting siding panels, additional connectors and similar devices have been used to prevent movement and separation of the ends of the siding panels. However, the use of separate connector pieces complicates the installation and assembly of the siding panels. 
         [0009]    The description herein of certain advantages and disadvantages of known methods and devices is not intended to limit the scope of the present invention. Indeed, the present embodiments may include some or all of the features described above without suffering from the same disadvantages. 
       SUMMARY OF THE INVENTION 
       [0010]    In view of the foregoing, it is a feature of the embodiments described herein to provide a system of panels that provides an improved end-to-end seam section with the outer surfaces of the joined panels providing a generally planar surface. In various embodiments, adjacent panels in a siding system may overlap and interlock at a seam section in a secure fashion. Once interlocked, the siding panels may expand and contract without causing a bulge or gap at the seam section. One benefit of siding panel assembly may be that the expansion and contraction associated with the individual siding panels is transferred to the ends of the assembly, rather than the end of each individual siding panel. Another benefit of the siding panel assembly of the embodiments is that it allows for a smoother seam between individual panels, so that it is less apparent from all viewing angles, unlike vinyl siding where the pieces are overlapped, to allow for expansion and contraction. 
         [0011]    In embodiments of the invention, a variety of geometries may be provided at the respective ends of adjacent panels (i.e. joints), including without limitation interlocking laps or overlapped ends, tongue and groove ends and butt joints. 
         [0012]    In some embodiments adjacent siding ends may by locked by friction fit and/or shape-driven mechanical fit. In various other embodiments the joints may include, without limitation, one or more of frictional fits, shaped mechanical fits, adhesives, mechanical fasteners, welds, melt-bonds and magnets. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0013]      FIG. 1  is a top plan view of two panels interlocked in a manner, according to exemplary embodiments of the invention; 
           [0014]      FIG. 2  is a cross-section view A-A of the two interlocked panels of  FIG. 1  showing an interlocking lap joint disclosed in U.S. Pat. No. 8,402,707, according to an exemplary embodiment of the invention; 
           [0015]      FIG. 3  is a cross-section view A-A of the two interlocked panels of  FIG. 1  showing an angled interlocking lap joint, according to an exemplary embodiment of the invention; 
           [0016]      FIG. 4  is a cross-section view A-A of the two interlocked panels of  FIG. 1  showing an interlocking lap joint with punch tap, according to an exemplary embodiment of the invention; 
           [0017]      FIG. 5  is a cross-section view A-A of the two interlocked panels of  FIG. 1  showing an interlocking lap joint with saw-tooth geometry, according to an exemplary embodiment of the invention; 
           [0018]      FIG. 6A-6C  are cross-section views A-A of the two interlocked panels of  FIG. 1  showing an arrow-head snap joint depicting a snap head pointing outward toward both opposite outer surfaces of a panel to interlock within a complementary recess  FIG. 6A , a snap head pointing outward toward a single outer surface of a panel to interlock within a complementary recess  FIG. 6B ), and a snap head pointing outward toward another (opposite direction from  FIG. 6B ) single outer surface of a panel to interlock within a complementary recess  FIG. 6C , according to exemplary embodiments of the invention; 
           [0019]      FIG. 7  is a cross-section view A-A of the two interlocked panels of  FIG. 1  showing a ratcheted tongue and groove joint, according to an exemplary embodiment of the invention; 
           [0020]      FIG. 8  is a cross-section view A-A of the two interlocked panels of  FIG. 1  showing a standard tongue and groove joint with glue, according to an exemplary embodiment of the invention; 
           [0021]      FIG. 9  is a is a cross-section view A-A of the two interlocked panels of  FIG. 1  showing a lap joint with glue, according to an exemplary embodiment of the invention; 
           [0022]      FIG. 10  is a cross-section view A-A of the two interlocked panels of  FIG. 1  showing a lap joint with an inner mechanical cleat, according to an exemplary embodiment of the invention; and 
           [0023]      FIG. 11  is a cross-section view A-A of the two interlocked panels of  FIG. 1  showing of a butt joint with an outer surface mechanical cleat, according to an exemplary embodiment of the invention. 
       
    
    
       [0024]    These and other exemplary embodiments and advantages will become apparent from the following detailed description, taken in conjunction with the accompanying drawings, illustrating by way of example the principles of the various exemplary embodiments. 
       DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS 
       [0025]    The following description is intended to convey a thorough understanding of the embodiments by providing a number of specific embodiments and details involving a siding panel assembly. It is understood, however, that the invention is not limited to these specific embodiments and details, which are exemplary only. It is further understood that one possessing ordinary skill in the art, in light of known devices, systems and methods, would appreciate the use of the invention for its intended purposes and benefits in any number of alternative embodiments. 
         [0026]    Generally speaking, as shown in  FIG. 1 , panel systems  100  of the present invention are generally flat sections used in building, construction and other applications, including in walls, siding, flooring, tiling, shelving, furniture and like. In one described but non-limiting embodiment, a panel system  100  of the invention includes siding panels  110  that have a plurality of horizontally adjacent siding panels  120  that are interlocked on their vertical ends  115  and  125  to provide a composite siding panel  200 . The siding panels  110  and  120  are joined together so that the composite siding panel  200  forms a single unit, such as in a row with outer-facing surfaces  117  and  127  of the siding panels providing an exterior siding surface of building in which a row of siding panels forms a substantially planar surface. Any horizontal expansion or contraction of the individual siding panels  110  or  120  is transferred to the end of the composite panel  200 , rather than causing gapping or buckling at the junction between two adjacent panels  110  and  120 . In some embodiments several composite siding panels  200  may be assembled in horizontal rows, adjacent other composite siding panels  200  along respective horizontal edges of the adjacent rows, to form a siding panel assembly (not shown) that covers a surface, such as the wall of a building. 
         [0027]    As used herein, the terms “horizontal” and “vertical” are not intended to be limited to a specific orientation and reflect generally perpendicular sides, edges or ends with respect to one another. The references of “horizontal” and “vertical” as describing one embodiment of the invention are intended to continue to reference the respective edge, side or end in other embodiments where a panel  110  or panel system  100  is provided in another orientation relative to the ground or horizon. 
         [0028]    In the various exemplary embodiments, the siding panel systems  100  and their components may be made from solid or foamed polymers, such as vinyl or cellular PVC. However, the embodiments are not so limited. The siding panel systems  100  and their components may be made from any known or later developed material used for siding panels including, but not limited to, wood, aluminum, steel and other metals, polymer materials, plastics, masonry, stone, brick, concrete, composites and combinations thereof. Panels of various materials may be shaped by extrusion, milling, molding, and the like. One having ordinary skill in the art would understand how to apply the teachings of various materials and panel manufacturing methods to various embodiments of the invention. 
         [0029]    Referring to  FIG. 2 , a cross section view A-A of one embodiment of the invention an interlocking lap joint for adjacent siding panels  110 A and  120 A in siding panel system  100 A is shown as described in U.S. Pat. No. 8,402,707, which is included herein by reference. Siding panel  110 A has an integrally formed interlock including a rectangular receiving groove  113 A and a rectangular projection  114 A at a vertical end. Siding panel  120 A has a mating integrally formed interlock including a rectangular receiving groove  123 A and a rectangular projection  124 A at a vertical end adjacent to the vertical end of siding panel  110 A. Siding panels  110 A and  120 A may be joined the their corresponding interlocks to form a composite siding panel  200 . 
         [0030]    Referring to  FIG. 3 , a cross section view A-A of one embodiment of the invention an interlocking lap joint for adjacent siding panels  1108  and  120 B in siding panel system  1008  is shown. Siding panel  1108  has an integrally formed interlock including a non-perpendicular parallelogram-shaped receiving groove  113 B and a non-perpendicular parallelogram-shaped projection  114 B at a vertical end. Siding panel  120 B has a mating integrally formed interlock including a non-perpendicular parallelogram-shaped receiving groove  1238  and a non-perpendicular parallelogram-shaped projection  124 B at a vertical end adjacent to the vertical end of siding panel  1108 . Siding panels  1108  and  120 B may be joined the their corresponding interlocks to form a composite siding panel  200 . The angled geometry of the interlock may provide a positive interlock between siding panels  1108  and  120 B. 
         [0031]    Referring to  FIG. 4 , a cross section view A-A of one embodiment of the invention an interlocking lap joint for adjacent siding panels  110 C and  120 C in siding panel system  100 C is shown. Siding panel  120 C has an integrally formed interlock including a receiving groove  123 C and a punched interlock tab  420  at a vertical end. Siding panel  110 C has a mating integrally formed interlock including a receiving groove  113 C and a rectangular projection  114 C at a vertical end adjacent to the vertical end of siding panel  120 C. Siding panels  110 C and  120 C may be joined the their corresponding interlocks to form a composite siding panel  200 . The punched interlock tab  420  of siding panel  110 C may retract into a recess in receiving groove  113 C during assembly of a composite siding panel  200  to allow for a more forgiving field installation and fitment between siding panels  110 C and  120 C. 
         [0032]    Referring to  FIG. 5 , a cross section view A-A of one embodiment of the invention an interlocking saw-tooth lap joint for adjacent siding panels  110 D and  120 D in siding panel system  100 D is shown. Siding panel  110 D has an intergally formed interlock including a flange  512  with a saw-tooth geometry surface  513 . Siding panel  120 D has a mating integrally formed interlock including a flange  522  with a saw-tooth geometry surface  523  at a vertical end adjacent to the vertical end of siding panel  110 D. Siding panels  110 D and  120 D may be joined the their corresponding interlocks with an adhesive to form a composite siding panel. The saw tooth geometry  512  and  522  of the flange surfaces may provide mechanical interlocking as well as greater surface area for adhesive bonding. 
         [0033]    Referring to  FIGS. 6A-6C , in another exemplary embodiment the invention siding panel system  100 E may include siding panels  110 E-G and  120 E-G which include an arrow-head snap fit geometry for interlocking joint attachment. Siding panel  110 E-G may include an arrow-head snap  612 E-G that may be inserted in a complementary recess  622 E-G in siding panel  120 E-G. The snap head  612 E-G and complementary recess  622 E-G may be shaped to secure a head pointing outward in multiple directions  612 E as shown in  FIG. 6A  or pointing in one of opposite directions  612 F and  612 G as shown in  FIG. 6B  and  FIG. 6C  resepctively. The snap fit geometry may provide a strong mechanical joint which may not require a bonding adhesive. 
         [0034]    Referring to  FIG. 7 , a cross section view A-A of one embodiment of the invention an interlocking ratcheted tongue and groove joint for adjacent siding panels  110 H and  120 H in siding panel system  100 H is shown. Siding panel  110 H has an integrally formed interlock including a ratcheted tongue  713  at a vertical end adjacent to the vertical end of siding panel  120 H. Siding panel  120 H has a mating integrally formed interlock including a receiving groove  723  at a vertical end. Receiving groove  723  may include a mating ratchet surface to ratcheted tongue  713 . Siding panels  110 H and  120 H may be joined the their corresponding interlocks to form a composite siding panel  200 . The interlock between receiving groove  723  and ratcheted tongue  713  may provide a tight mechanical fit which may not require adhesive or other bonding means. 
         [0035]    Referring to  FIG. 8 , a cross section view A-A of one embodiment of the invention an interlocking standard tongue and groove for adjacent siding panels  110 J and  120 J in siding panel system  100 J is shown. Siding panel  110 J has an integrally formed interlock including tongue  813  at a vertical end adjacent to the vertical end of siding panel  120 J. Siding panel  120 J has a mating integrally formed interlock including a receiving groove  823  at a vertical end. Siding panels  110 J and  120 J may be joined the their corresponding interlocks to form a composite siding panel  200 . The interlock between receiving slot  823  and tab  813  may be secured at the joint by an adhesive. The tongue and groove interlock may simplify fabrication of the siding panels  110 J and  120 J. The adhesive bond between siding panels  110 J and  120 J may also provide added strength to the interlock. 
         [0036]    Referring to  FIG. 9 , a cross section view A-A of one embodiment of the invention a lap joint for adjacent siding panels  110 K and  120 K in siding panel system  100 K is shown. Siding panel  110 K has an intergally formed flange  912 . Siding panel  120 K has a mating integrally formed flange  922  at a vertical end adjacent to the vertical end of siding panel  110 K. Siding panels  110 K and  120 K may be joined the their corresponding interlocks with an adhesive to form a composite siding panel  200 . The simple geometry of the flanges may simplify fabrication of the siding panels  110 K and  120 K. The adhesive bond between siding panels  110 K and  120 K may also provide added strength to the siding panel system  100 K. 
         [0037]    Referring to  FIG. 10 , a cross section view A-A of one embodiment of the invention a lap joint for adjacent siding panels  110 L and  120 L in siding panel system  100 L is shown. Siding panel  110 L has an integrally formed flange  1012 . Siding panel  120 L has a mating integrally formed flange  1022  at a vertical end adjacent to the vertical end of siding panel  110 L. Siding panels  110 L and  120 L may be joined the their corresponding interlocks with a mechanical cleat  1030  to form a composite siding panel  200 . The mechanical cleat  1030  may include barbs or other protrusions that may pierce or otherwise deform the mating surfaces of flanges  1012  and  1022  to grip and interlock siding panels  110 L and  120 L to form a composite siding panel  200 . The mechanical cleat  1030  may be made of metals, plastics or the like. Flanges  1012  and  1022  may provide a relief space for the mechanical cleat  1030  so the mechanical cleat  1030  may be inserted while allowing the outer surfaces of siding panels  110 L and  120 L to remain substantially parallel. 
         [0038]    Referring to  FIG. 11 , in another embodiment siding panel  110 M and  120 M ends may be joined as a butt joint  1110  with one or more mechanical fasteners  1130 , such as a cleat across a seam of one or both outer surfaces of created by the adjacent siding panel  110 M and  120 M. The mechanical fastener  1130  may include barbs or other protrusions that may pierce or otherwise deform the outer surfaces of flanges siding panels  110 M and  120 M to form a composite siding panel  200 . The mechanical fastener  1130  may be made of metals, plastics or the like. In other embodiments, fastening components may include, without limitation, one or more of adhesives, welds, mechanical fasteners, melt-bonds and magnets. 
         [0039]    Referring to  FIGS. 2-11 , in other exemplary embodiments, various other interlocking lap geometries may be provided to secure ends of adjacent siding panels. Such geometries may be secured at the joint by, without limitation, by one or more of frictional fits, shaped mechanical fits, adhesives, mechanical fasteners, welds, melt-bonds and magnets. 
         [0040]    In the preceding specification, various preferred exemplary embodiments have been described with reference to the accompanying drawings. It will, however, be evident that various modifications and changes may be made thereto, and additional exemplary embodiments may be implemented, without departing from the broader scope of the invention as may be set forth in such patent claims as may be based on this application and specification. The specification and drawings are accordingly to be regarded in an illustrative rather than restrictive sense.