Patent Publication Number: US-8985183-B2

Title: Mesh screen tensioner and related method

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     This application seeks priority to U.S. Provisional Patent Application Ser. No. 61/546,728 filed on Oct. 13, 2011 entitled “Mesh Screen Tensioner Assembly,” the contents of which are incorporated by reference herein. 
    
    
     FIELD OF THE INVENTION 
     The present invention relates to screen assemblies. More specifically, the invention teaches an assembly to secure and provide tension to a mesh screen installed in a door, window, or general screen frame and related methods. 
     BACKGROUND 
     Screen mesh is a material commonly stretched between wooden or metal frames, and is designed to cover window or door openings. Screen mesh is also used to enclose areas, such as decks and swimming pools. The primary purposes of these assemblies is generally to keep debris, insects, animals, and ultraviolet rays out of the areas protected by the screen mesh, while allowing light into the same area. Some screen mesh, however, is constructed of relatively strong material, such as stainless steel, and is installed to provide security and protection from intruders, dynamic impact, and knife shear. 
     The primary role or purpose of these screens varies based upon the geographic area. For example, homes situated in regions with large mosquito populations typically utilize screens on all operable windows (and optionally doors). Areas with large amounts of sun may employ screens to occlude light and limit harmful UV rays past the screen. Security screen is used in regions that routinely experience harsh weather events, such as tropical storms and hurricanes. Security screen is also used to protect businesses and residences from unwanted intruders. 
     Security screens are almost universally constructed with the use of frame assemblies. These frame assemblies can rest within a door or window opening so that the screen mesh spans across the opening, utilizing the frame as a physical attachment point. Similarly, areas such as porches and pools often have large framed structures that define wall and ceiling frames that support mesh screen. 
     Despite the popularity of mesh screens, there is a need in the art of frame assemblies for a more secure design that allows greater function in the event of intrusion or severe weather events. Additionally, steel mesh is susceptible to galvanic corrosion from contact with fasteners and frames made from different metals, such as aluminum. Additionally, maintaining and adjusting tension of screen panels is often difficult. Improvement in the field is necessary. 
     SUMMARY OF THE INVENTION 
     The following invention provides a frame assembly for a more robust and durable design that helps more properly secure mesh screen to a window or door. Moreover, the instant invention provides a more adjustable frame assembly which allows regions of varying screen tension to be adjusted upon installation. Additionally, by eschewing the use of fasteners that protrude through the steel mesh, deterioration due to galvanic corrosion is eliminated. 
     The invention contemplates a screen tensioning system having a mesh screen and a U-shaped channel that engages an edge of the mesh screen. A clamp engages the U-shaped channel and the mesh screen, and the clamp defines a slot having a shape and dimension for the mesh screen to extend through the slot, yet is too small to allow the U-shaped channel to pass. A frame that has two substantially parallel side members and a connecting member joining the two substantially parallel side members forms a substantially H-shaped cross section. Additionally, the two substantially parallel side members converge on a first end of the frame to define a longitudinal slot having a size and dimension to permit the mesh screen to extend through the longitudinal slot. There is a plurality of holes in the connecting member. A plurality of fasteners passes through the holes in the connecting member to engage the clamp. The fasteners are tightened in order to apply tension to the screen. 
     In one embodiment, the edge of the mesh is secured with an adhesive, which can optionally be a metal epoxy. The fasteners to tension the screen or to close the clamp may be machine screws. 
     In a related embodiment, a clamp defines a plurality of slits that pass substantially through the clamp, the plurality of slits having an orientation perpendicular to a long axis of the clamp. This allows the clamp to be easily deformed so that tension may be differentially applied along the length of the screen. 
     In another embodiment, a screen tensioning system comprises a mesh screen having a plurality of edges each edge having a thickness greater than a thickness of a central region of the mesh screen. Additionally, a plurality of clamps securely engages each one of the plurality of edges. A substantially rectangular frame assembly has four internal edges that each securely engage one of the plurality of clamps, wherein the screen is secured within the frame assembly. Alternatively, a channel may be affixed to each one of the plurality of edges to provide a greater area for the clamp to engage, which may be accomplished with epoxy. Fasteners with the frame engage the clamps and frame to provide tension to the screen. 
     The invention also contemplates a method of securing a security screen to a frame. The method comprises the steps of: securing an edge of a security screen to a U-shaped channel extending substantially a length of the edge of the security screen; clamping the U-shaped channel in a clamp assembly that is substantially coextensive with the U-shaped channel; sliding the clamp assembly into a frame member having a size and dimension to entrap the clamp assembly; securing the clamp assembly to the frame member; and applying tension to the screen. 
     In another embodiment of the method, an adhesive, preferably, is used to secure the edge of the security screen to the U-shaped channel. In related embodiments, a plurality of metal fasteners engages the clamp to securely close the clamp and to also secure the clamp assembly to the frame member. 
     A related method of securing a security screen to a frame further comprises the step of providing tension to the screen by tightening at least some of the plurality of metal fasteners. This tension may be varied along the length of the screen. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       For a fuller understanding of the invention, reference is made to the following detailed description, taken in connection with the accompanying drawings illustrating various embodiments of the present invention, in which: 
         FIG. 1  is a cut away side view of the frame assembly wherein a mesh screen is affixed; 
         FIG. 2  is a perspective view of the frame assembly of  FIG. 1 ; and 
         FIG. 3  is an exploded perspective view of the frame assembly of  FIGS. 1 and 2 ; and 
         FIG. 4  is a perspective view of an embodiment of a frame assembly. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     The present invention will now be described more fully hereinafter with reference to the accompanying drawings, in which preferred embodiments of the invention are shown. This invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art. Like numbers refer to like elements throughout. 
       FIGS. 1-3  illustrate a preferred embodiment of a screen tensioning system having a frame  100  onto which a mesh screen  102  is engaged. Turning first to  FIGS. 1 and 2 , the frame  100  is defined by two primary regions: two substantially parallel side members  104  connected by a substantially perpendicular connecting member  106 , forming roughly an H-beam cross section. Proximate a first region  108  of the frame  100 , the side members  104  converge to define a longitudinal slot  110  through which the mesh screen  102  can pass. 
     With continuing reference to  FIGS. 1 and 2  and also  FIG. 3 , a clamp  112  is slideable into a first compartment  114  defined by the frame  100 . The clamp  112  is made from a single piece of material, or alternatively as illustrated made from a top portion  116  and a bottom portion  118 . Clamping pressure is adjusted with metal fasteners  120 , such as machine screws that pass partially through and engage one of the clamp portions and engage mating threads in the other clamp portion. 
     The mesh screen  102  is bent proximate an edge  122  of the mesh screen  102  to form a lip  124 . The lip  124  fits into a U-shaped channel  126  that is preferably made from the same or similar material type as the mesh screen  102 . To permanently secure the lip  124  into the channel  126 , an adhesive  128  is placed into the channel  126  and adheres to both the channel  126  and the lip  124 . The adhesive  128  is preferably an epoxy. 
     The channel  126  with the mesh screen  102  adhered engages the clamp  112 , and more particularly a slot  130  with the clamp  112 . When the clamp  112  is engaged about the channel  126  and mesh screen  102 , a screen slot  132  that projects the length of the clamp  112  is defined that permits the mesh screen  102  to pass there through. The screen slot  132  is only large enough to allow the screen to pass through, and does not permit the channel  126  and lip  124  to pass, thereby securing the mesh screen  102  to the clamp  112 . Since no metal fasteners such as sheet metal screws are used to attach the mesh screen  102  to the clamp  112 , fasteners do not protrude through the mesh screen  102  that could otherwise create a localized source of galvanic corrosion. 
     As most clearly illustrated by  FIG. 3 , to assemble the invention, the clamp  112  secured to the mesh screen  102  slides into the first compartment  114  and is secured to the frame  100 . Tensioning screws  132  pass through holes  134  in the connecting member  106  and engage mating threads in the clamp  112 . The greater the number of rotations the tensioning screws  132  are turned, the closer the clamp is positioned to the connecting member  106 . In this manner, tension is applied to the mesh screen  102  by increasing the number of rotations the tensioning screws  132  are turned into the clamp  112 . 
     In order to adjust tension only in local regions of the mesh screen  102  or frame  100 , tensioning screws  132  are each adjusted to impart varying degrees of tension. In one embodiment, a plurality of slits  134  are present with the clamp  112 . The slits  134  allow an increased degree of movement for individual clamp segments  136 , thus providing adjustability of local mesh screen  102  and frame  100  regions. This results in regions of variable mesh screen  102  tension that could not easily be achieved where the clamp  112  was made of a non-segmented construction. The segments  136  may be separate pieces, or alternatively connected regions of the clamp  112 , as depicted in the figures herein. 
       FIGS. 1-3  also illustrate a sealing member  138 . The sealing member  138  engages a second region  140  of the frame  100 . The sealing member  138  acts as a decorative cap to hide the internal region of the frame  100 , but also may, in another embodiment, provide a weather tight seal for the frame. Barbs  142  with the sealing member  138  engage projections  144  of the frame  100  to secure the sealing member  138  to the frame  100 .  FIG. 4  illustrates a double sealing member  146  that acts as a weather seal, but also, in another embodiment, a rail to attach two frames  100  to each other. This is used adjoin multiple frame assemblies. 
     In a preferred embodiment, the mesh screen  102  is made of stainless steel and the U-shaped channel  126  is also stainless steel. Other metals are, however, also contemplated, as are plastics, polymeric compounds, composite materials, and ceramics. The frame  100  and the clamp  112  are preferably aluminum, but stainless steel and other metals are also contemplated. 
     The invention also contemplates a method for securing and tensioning mesh screen  102  to a frame  100 . The method comprises a number of steps: The edge or lip  122 , 124  of the mesh screen  102  is placed into the channel  126 . The channel  126  is then clamped in the clamp assembly  112  that is substantially coextensive with the channel  126 . The clamp  112  is slid into the first compartment  114  of the frame  100  and secured to the frame  100 . Tension is then applied to the mesh screen  102 . 
     In a related method, adhesive  128  is used to secure the edge  122  of the security screen to the U-shaped channel  126 . A plurality of metal fasteners  120  engage the clamp  112  to securely close the clamp. Additionally, the clamp  112  assembly is secured to the frame  100  using metal fasteners  132 . The method of securing the mesh screen  102  to the frame  100  may additionally include the step of providing tension to the mesh screen  102  by tightening at least some of the plurality of metal fasteners  132 . This makes adjusting the tension at local regions of mesh screen  102  or frame  100  possible for the best fit possible. In a variation of the method of securing the security mesh screen  102  to the frame  100 , tension levels are differentially applied along the length of the mesh screen  102 .