Patent Publication Number: US-9410362-B1

Title: Thermal break system

Description:
BACKGROUND OF THE INVENTION 
     This present disclosure relates to retrofit window insulation systems, specifically windows that are added to existing windows and window frames. A significant amount of effort and attention are spent towards increasing the thermal insulating properties of existing windows, as that is a primary source of energy loss in a building. Existing technologies focus on the window pane (by increasing the number or thickness of panes, inert gas, and coatings), but completely neglect the frame. The frame in most office windows is made from aluminum, an excellent conductor of heat. An improved retrofit window solution is needed. 
     SUMMARY OF THE INVENTION 
     The present disclosure describes an additional layer of insulation that is placed over the existing frame before any retrofit window is installed. The layer has a significantly lower thermal conductivity as compared to the aluminum frame it covers. By covering up the existing window and frame, a higher insulation value can be assigned to the retrofit system with the cap as compared to the system without the cap. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       A preferred embodiment of this invention has been chosen wherein: 
         FIG. 1  is a horizontal section view of the thermal break system; 
         FIG. 2  is a partial view of the left side of the break system in  FIG. 1 ; 
         FIG. 3  is a partial view of the right side of the break system in  FIG. 1 ; 
         FIG. 4  is a vertical section view of the thermal break system; 
         FIG. 5  is a partial view of the upper break system in  FIG. 4 ; 
         FIG. 6  is a partial view of the lower break system in  FIG. 4 ; and 
         FIG. 7  is an alternate embodiment of the thermal break cap. 
     
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT 
     A building wall  10  has an outside surface  12  and an inside surface  14  and an opening defined by a surface  16   FIG. 2  that connects the inside surface  14  to the outside surface  12 . In the opening, an existing window  20   FIG. 4  is mounted, usually to the surface  16 . The existing window  20  has an existing frame  18  which mounts an existing window pane  22  as shown in  FIGS. 1, 2 and 3 . The existing window pane  22  has an outside surface  24  and an inside surface  26 . The existing window pane  22  is usually held to the existing frame  18  with a gasket  32  or adhesive. The existing frame  18  is usually sealed to the surface  16  as is commonly known in the art. The existing frame  18  has inside facing surfaces  28  and  30 . This retrofit thermal break system is designed to mount on the inside of an existing window  20 , specifically the frame  18 . The existing frame  18  can also span between two adjacent existing windows  20  as is shown in  FIG. 3 . 
     The retrofit system has a cap  40  which is a single-piece wall. The cap  40  has a first portion  50  and a second portion  52 . The first portion  50  intersects the second portion  52  at a slightly acute angle and is made from a material that has lower thermal conductivity than the frame  18 . The cap  40  is made from a semi-rigid material which will allow it to flex slightly as installation requires. The cap  40  has exposed surfaces  42  and  44  on portions  50  and  52   FIG. 2  respectively. The cap  40  also has inner surfaces  46  and  48  and protrusions  54  that extend outward as shown in  FIGS. 2 and 3 . The protrusions  54  form a mating surface  60   FIG. 2 . The protrusions  54  are intended to separate the cap  40  thermally from the existing frame  18  by trapping air between the inner surfaces  46 ,  48  and their corresponding exposed surfaces  28 ,  30 . The cap  40  can have more than one first portion as is shown in  FIGS. 1, 2 and 3 . The protrusions  54  can form individual cavities or be separated. The cap  40  has lateral edges  56 ,  58   FIG. 2  at opposing terminal ends. The exposed surface  42  is designed to receive a mounting for the remainder of the components of the system as shown in all FIGS. 
     A retrofit window system is also made up of a mounted portion and a removable panel. The mounted portion includes side rails  70 , a top channel  72 , and a bottom channel  74 ,  FIG. 4 . The cap  40 , specifically the exposed surface  42 , is adapted to receive the side rails  70 , top channel  72 , and bottom channel  74 . These can be attached to the exposed surface  42  via screws  71   FIG. 2 , adhesive, rivets, or other fastening means. The side rails  70  are steel or another metal that is attracted to a magnetic field. The top channel  72  is deeper than the bottom channel  74  to allow the panel clearance to be lifted up and be placed into the bottom channel  74 , shown best on  FIG. 4 . The removable panel includes a window pane  76  and a sash  78  that encircles the window pane  76   FIG. 2 . A gasket  80  secures the window pane  76  to the sash  78  and seals it. The sash  78  includes a channel  82  that holds a magnet  84  or a wool pile  86   FIGS. 5 and 6 . As is shown in  FIG. 2 , the magnet  84  is located such that when the panel is installed, the outside facing surface  88  overlays the inside facing surface  90  of the side rail  70 . 
     A panel with a sash  78  surrounds the perimeter of a window pane  76 . Pane  76  is a window pane, such as formed from glass, plastic, or a composite, preferably formed from a material suitable for insulation. The pane  76  is typically a flat planar surface with a perimeter. The pane  76 , as shown, is double-paned; other styles and number of panes are possible. The sash  78  as shown in all FIGS is formed from an aluminum extrusion with a groove formed from parallel upstanding walls  92 ,  94   FIG. 2  for receiving a window gasket  80 . The interior surfaces of the upstanding walls  92 ,  94  may have ridges to retain the gasket  80 . Between upstanding walls  92 ,  94 , is a slot  96  for receiving a screw. Where sides of the sash  78  meet, the extrusion is cut at a 45° angle to form the mating surfaces of a corner. A hole is drilled in the adjacent/perpendicular sash member that is inline with the slot  96 . The slot  96  is adapted to receive a self-tapping screw as is commonly known in the art. A screw (not shown) is inserted through the drilled hole and engages with the slot  96  to affix the adjacent sash members. The gasket  80  fits between upstanding walls  92 ,  94  and is adapted to receive window pane  76 . It is possible that the pane  76  is secured to the sash  78  through adhesive, silicone, or other method instead of a gasket  80 . As shown in  FIGS. 1 and 2 , a groove  82  in the exterior face of the sash  78  is adapted to receive a tongue of a magnet  84  or a wool pile  86 . The magnet  84  overlies a portion of the exterior face of the sash  78 , and is held to the sash  78  by the fit between the tongue and groove  82 . In the embodiment as shown in  FIGS. 1 through 3 , the tongue is a protrusion and groove  82  is a channel that is adapted to receive the tongue. The magnet  84  or wool pile  86  is alternatively held to the sash  78  by adhesive, fasteners, or other means as are known in the art. The magnet  84  has an outward facing surface  88  and is charged to attract a ferromagnetic metal to the mating surface of side rail  70 . On the top and bottom portions of the sash  78 , instead of the magnet  84  in the groove, a wool pile  86  is installed. The wool pile  86  is designed to conform and distort as it mates up with another surface, thereby lowering the amount of air infiltration between the window pane and the adjacent channel  72 ,  74 . 
     An exterior stop  70  as shown in  FIGS. 1 through 3  is part of the system and is fastened to the sides of the existing frame  18  and thermal break cap  40 . The exterior stop  70  serves to hold the sides of the sash  78  towards the exterior surface and limits the movement of the window panel in the exterior direction. The exterior stop  70  includes an exterior lip portion and a wall portion to form an L-shaped member. The lip portion and wall portion will be referred to hereinafter as lip and wall. The exterior stop  70  has an interior facing surface  88  as shown in  FIG. 2 . The exterior stop  70  is secured to the existing frame  18  and thermal break  40  by fasteners through the thermal break  40 . As installed on the thermal break  40 , the exterior lip extends perpendicularly therefrom. Exterior stop  70  is preferably formed from a ferromagnetic material, such as angle iron or stamped steel, to allow the magnet  84  to hold the sash  78  to the exterior stop  70 . Optionally an adhesive tape or dispensed adhesive may be used between thermal break  40  and exterior stop  70  to hold it during installation prior to the fastener being installed through the wall to simplify installation of the system. Properly placed adhesive also prevents or reduces air infiltration. The window panel, specifically the distance between opposing surfaces of the perimeter  79 , is smaller than the distance between opposing exterior stops  70  to compensate for size variations, sill irregularity, thermal expansion, and building movement. The gap formed between the perimeter  79  of the sash  78  and the exterior stop  70  is visible in  FIG. 2 , allowing for limited lateral movement. 
     For assembly of the system, the thermal break  40  is trimmed or sized to fit over the existing frame  18 . In order for the second portion  52   FIGS. 2, 3, 4, and 7  to properly mate to exposed surface  30 , the first portion  50  must be sized the same or smaller than the length of exposed surface  28 . In the event that the thermal break  40  is installed on the existing frame  18  that is adjacent to the building wall  10 , the second portion  52  is sized to mate the terminal end  58   FIGS. 2 and 7  flush to the opening surface  16 . The first portion  50  is sized to mate to either the existing gasket  32   FIGS. 1, 3, 4, and 6  or the inside facing surface  26  of the existing window pane  22 . It is also possible to size the first portion  50  to have a gap between the terminal end  56  and the gasket  32  or inside surface  26  of the existing window. In the event that the thermal break  40  is installed on an intermediate part of the existing frame  18  (as shown in  FIG. 3 ) the second portion  52  is sized to space opposing first portions  50  to snugly fit to exposed surfaces  28 . The angle between the first portion  50  and the second portion  52  is preferentially slightly less than 90 degrees so that the mating surface  60  near terminal ends  56  and  58  are kept in biased contact with the exposed surfaces. 
     The system is built by taking a pane  76 , sash  78 , magnet  84  wool pile  86 , and gasket  54  and assembling them into a window assembly. The magnets  84  are slid into the portions of the sash  78  that will be the sides of the panel. The wool pile  86  is slid into portions of the sash  78  that will be at the top and bottom. The gasket  54  circumscribes the perimeter of the pane  76  and the frame is cut to size. Corners are miter cut from the sash extrusion then mated, typically at a 45° angle, then a screw is installed through one side of the corner and into the slot  72  of the adjacent sash extrusion. Screws at each corner hold the sash extrusion parts together to form a continuous sash  78  that circumscribes the window pane  76 . The cap  40  is either trimmed or sized before installation to mate properly with the inside facing surfaces  28 ,  30  of the existing frame  18 . Next, the side rails  70 , top channel  72 , and bottom channel  74  are sized and overlay the exposed surface  42 . The side rails  70 , top channel  72 , and bottom channel  74  are then secured to the existing frame  18  through rivets, screws  71 , or other means. It is possible that the cap  40  is secured independently to the existing frame  18 , and then the side rails  70 , top channel  72 , and bottom channel  74  are secured to the exposed surface  42 . The window panel is then lifted into position where the sash  78  is first placed into the top channel  72 , then the bottom channel  74 . This puts the outside facing surface  88  of the magnet  84  into contact with the inside facing surface  90  of the exterior stop  70 . 
     Optionally, the cap  40  contains a ledge that serves as an installation aid. The ledge forms a positive stop for the side rails  70 , top channel  72 , and bottom channel  74  to position them before they are secured. This ensures the system will be installed squarely and evenly spaced from the existing window and frame. 
     It is understood that while certain aspects of the disclosed subject matter have been shown and described, the disclosed subject matter is not limited thereto and encompasses various other embodiments and aspects. No specific limitation with respect to the specific embodiments disclosed herein is intended or should be inferred. Modifications may be made to the disclosed subject matter as set forth in the following claims.