Patent Publication Number: US-2009217606-A1

Title: Joining panels of sheet material

Description:
FIELD OF THE INVENTION 
     The present invention relates to a system and method for joining adjacent edges of respective panels of sheet material. The system and method may find particular application for the joining of plaster boards for ceilings and walls. 
     BACKGROUND OF THE INVENTION 
     There are various techniques for joining together adjacent panels of sheet material. The most common joining system uses tongue-in-groove joints, where one panel has a tongue projecting from its edge and an adjacent panel has a groove extending along its edge. The tongue is inserted into the groove. Adhesive may be used to secure the panels together. Additional fasteners, such as nails or screws, may then be used to further assure the assembly. 
     When using plaster boards to create a ceiling or wall, the plaster boards are provided in standard lengths and widths. The plaster board lengths are provided with a recessed edge at each side of the plaster board. When two panels are joined together, to form what is referred to as a recessed edge join, approved fillers can be applied for a smooth, even join, along the longitudinal edges of the boards. The join is generally not visible once the wall or ceiling is finished. 
     However, the ends of the plaster board lengths do not have recessed edges. This is due to the plaster board length needing to be cut to size to suit the particular application. Currently, the lateral edges of the two adjacent plaster boards are joined as a butt joint. This is where the two square-cut edges simply abut with adhesive between them. The join is then finished off in the standard way, with tape and plaster filler. As there is no positive engagement between the two plaster board lengths, additional material is required over the join to maintain integrity and conceal the join. Unfortunately, this additional material results in the join being visible, even after the wall or ceiling is finished. As there is no positive engagement, the two panels may drop out of alignment with each other, making the join visible. 
     Whilst a suitable solution would be to provide a recessed edge join across the lateral edges, this is not practical, as then the plaster board lengths could not be cut to size. This would require the plaster board manufacturer to provide the plaster boards in a variety of lengths. This would greatly increase the cost of plaster boards. 
     U.S. Pat. Nos. 1,967,846, 5,657,599, 5,799,458 and 6,108,990 have attempted to provide improved systems of joining panels of sheet material. These systems have a component that extends along the rear of the join and has a recess aligned with the join. A separate line of fasteners for each sheet is used to deform the respective sheets into the recess, leaving a depression on the front of the join that can be filled with suitable filler material. 
     It is an object of the present invention to provide an improved method and system for joining adjacent edges of respective panels of sheet material. 
     SUMMARY OF THE INVENTION 
     According to a first aspect of the invention, there is provided a system for joining adjacent edges of respective panels of sheet material, the system including:
         a first component adapted to be positioned over the front of the adjacent edges;   a second component adapted to be positioned behind the adjacent edges, the second component having a recess capable of receiving at least a portion of the first component; and   fastening means for clamping the first and second components together in a manner that deforms the adjacent edges into the recess, whilst simultaneously forming a depression at the front of the adjacent edges able to be filled with a compatible material to conceal the adjacent edges.       

     Preferably, the fastening means is a nail or screw. However, it will be appreciated that any suitable fastening means may be used. Alternatively, the fastening means may be integral with either the first or second component. 
     Advantageously, the first component has a slightly curved cross-section, such that when the fastening means is clamping the first and second components together, the fastening means does not project past the first component. Alternatively, the first component may be flexible, such that it is flat when not in use and flexes when the fastening means clamps the first and second components together. The first component is preferably elongate. The first component may be made from metal. The first component may be a plate of steel with an array of apertures. Advantageously, the first component could be a mesh, and more preferably is an expanded metal. The apertures or holes provided in the first component allow the compatible material, such as plaster filler, to fill the depression at the front of the adjacent edges. 
     The second component is advantageously an elongate channel which forms the recess. Alternatively, the second component is a plate having a cross-section that is a shallow inverted “v”. The second component may be made from steel, aluminium, wood, or any other suitable material. 
     The first component and the fastening means are preferably dimensioned such that, once clamped, they are seated below the flush front surfaces of the respective panels. According to a second aspect of the invention, there is provided a method for joining adjacent edges of respective panels of sheet material, the method including:
         positioning a first component over the front of the adjacent edges;   positioning a second component behind the adjacent edges, the second component having a recess capable of receiving at least a portion of the first component; and   clamping the first and second components together, such that the adjacent edges deform into the recess, whilst simultaneously forming a depression at the front side of the adjacent edges able to be filled with a compatible material to conceal the adjacent edges.       

     The first and second components may be positioned in any order. The clamping of the first and second components may be by the use of fastening means, such as nails or screws. 
     In a third aspect of the invention, there is provided a kit for joining adjacent edges of respective panels of sheet material, the kit including:
         a first elongate component adapted to be positioned over the front of the adjacent edges; and   a second elongate component adapted to be positioned behind the adjacent edges, the second elongate component having a recess capable of receiving at least a portion of the first component;   wherein, the first and second elongate components are adapted to receive fastening means for clamping the first and second elongate components together in a manner that deforms the adjacent edges into the recess, whilst simultaneously forming a depression at the front side of the adjacent edges able to be filled with a compatible material to conceal the adjacent edges.       

     Advantageously, the kit includes the fastening means. The fastening means may be a nail or screw or any other suitable means. 
     Preferably, the first elongate component has a slightly curved cross-section, or is flexible, such that when the first and second components are clamped together, the fastening means does not project past the first component. 
     The second component preferably consists of a top plate and respective lips at opposite longitudinal edges of the top plate to define the recess. Alternatively, the second component consists of a plate that is slightly bent along a central ridge to form a shallow inverted “v”. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The invention will now be described, by way of example only, with reference to the accompanying drawings, in which: 
         FIG. 1  is a cross-sectional side view of a system for joining adjacent edges of respective panels of sheet material, shown with the fastening means in the unclamped position; 
         FIG. 2  is a cross-sectional side view of the system of  FIG. 1 , shown with the fastening means in the clamped position; 
         FIG. 3  is a cross-sectional perspective view of the system of  FIG. 1 , without the panels of sheet material; 
         FIG. 4  is a cross-sectional perspective view similar to  FIG. 3  of an alternative system; and 
         FIG. 5  is a perspective view of the system of  FIG. 4  installed. 
     
    
    
     DETAILED DESCRIPTION OF THE EMBODIMENTS 
       FIGS. 1 and 2  show a system  10  for joining adjacent edges  12 ,  14  of respective panels  16 ,  18  of sheet material, such as plaster board. A plurality of panels  16 ,  18  may be joined together to create a structure such as a ceiling or wall. The panels  16 ,  18  have a front surface  20  and a back surface  22 , with the back surface  22  being positioned against the timber ceiling or wall joists  24 . 
     The system  10  includes a first component  26 , a second component  28  and fastening means  30 . In the embodiment illustrated, the second component  28  is an integral elongate channel having a top plate  32  and respective lips  34 ,  36  at the opposite longitudinal edges of plate  32  that define a longitudinally extending recess  38 . The second component  28  is positioned behind the adjacent edges  12 ,  14 , such that the bottom surfaces  40 ,  42  of the lips  34 ,  36  abut the back surface  22  of the panels  16 ,  18 . The second component  28  will typically run the entire width of the panels  16 ,  18  and therefore will generally be either 1190 mm or 1340 mm in length. The width of the second component  28  is preferably 200 to 300 mm and the depth of the recess  38  is preferably 50 mm. However, it will be appreciated that the dimensions may differ from those mentioned. 
     The first component  26  is an elongate transversely curved plate, having an array of apertures  44 . The first component  26  may be an expanded metal, or a rigid mesh. The convex side  46  is positioned over the front of the adjacent edges  12 ,  14 . The first component  26  is dimensioned so that at least a portion of it is capable of being received within the recess  38  of the second component  28 , by having a width that is smaller than the width of the recess  38 . 
     Fastening means  30  are illustrated as a plurality of nails arranged at intervals longitudinally of the first and second components  26 ,  28 , as shown in  FIG. 3 . The nails are inserted through the first component  26 , between the edges  12 ,  14  and a hammer is used against the head  50  to force the nail  30  through the second component  28  to clamp the first and second components  26 ,  28  together. 
     It will be appreciated that any suitable fastening means may be provided, and that such fastening means may be provided separately or integrally with either the first or second components  26 ,  28 . The fastening means may be provided in the form of a one-way tapered pin on the first component  26 , which pin is pushed through and retained in an aperture in the second component  28 , locking the two components together. 
     As can be seen best in  FIG. 2 , the fastening means  30  is inserted through the first component  26 , which is positioned over the front of the adjacent edges  12 ,  14  and through the second component  28 , sitting between the edges  12 ,  14 . As the fastening means  30  clamps the first component  26  towards the second component  28 , the edges  12 ,  14  are deformed into the recess  38 , bending about the bottom surfaces  40 ,  42  of the lips  34 ,  36 . Simultaneously, a depression  48  is formed at the front side of the adjacent edges  12 ,  14 . Due to the curved form of the first component  26 , the head  50  of the fastening means  30  does not project past the first component  26 . The depression  48  allows the first component  26  and the fastening means  30  to be seated below the flush front surfaces  20  of the panels  16 ,  18 . 
     As seen in  FIGS. 2 and 5 , a compatible material  52 , such as plaster filler, can be used to fill the depression  48  to conceal the adjacent edges  12 ,  14 , as well as the heads  50  of the fasteners  30 . By creating the depression  48 , the compatible material  52  can be filled so that it is flush with the front surfaces  20  of the panels  16 ,  18 . The apertures  44  in the first component  26  are provided to allow the compatible material  52  to fill the entire depression  48 . This enables the wall or ceiling to be finished in the standard way and the join is concealed. 
     A system  110  including alternative forms of the first and second components  126 ,  128  is shown in  FIG. 4 . The first component  126  has a flat cross-section and is made from expanded metal such that it is flexible. When the fastening means  150  clamps the first and second components  126 ,  128  together, the first component  126  flexes so the fastening means  150  does not project past the first component. The second component  126  is formed from a plate  132  that has a slight bend along a central ridge, such that a shallow inverted “v” is formed. The recess  138  is defined by the space under the inverted “v”. 
     It will be understood that the invention disclosed and defined in this specification extends to all alternative combinations of two or more of the individual features mentioned or evident from the text or drawings. All of these different combinations constitute various alternative aspects of the invention.