Abstract:
A glass assembly for a dwelling having a first pane and a second pane integrated together with at least one spacer for encapsulating an inert gas forming an insulated glass unit. The first and second panes define an outer periphery and an internal periphery. The internal periphery defines a pet channel and the two panes have openings for receiving a pet door. A pet is enabled to pass from one side of the glass assembly, through the glass assembly, and exiting on the other side of the glass assembly while the inert gas is maintained within the insulated glass unit.

Description:
FIELD OF THE INVENTION 
     The present invention relates generally to insulating glass units. More specifically, the invention relates to methods of producing insulating glass units which have been manufactured to retain its insulating properties while enabling interfacing with a pet door assembly either as an integrated unit or adaptive to receiving a pet door assembly. 
     BACKGROUND OF THE INVENTION 
     An insulating glass unit (i.e., an “IG unit” or “IGU”) typically includes a pair of generally parallel panes held in a spaced-apart relationship by a spacer. The basic structure of a conventional double-glazed IG unit includes peripheral inner surfaces of the panes joined by a space to define a between-pane space. While many standard IG units simply contain air, high performance IG units are sometimes filled with insulating gas to increase the insulating capacity of the units. Filling the between-pane space of an IG unit with insulating gas advantageously increases the “R” value (i.e., the resistance to heat flow through the unit) of the resulting unit. Ideally, the between-pane space is filled with a gas that is heavier and less thermally conductive than air. Argon is commonly used as an insulating gas fill. Krypton is an even better insulator than argon. However, it is also significantly more expensive. Other inert gases can be used as well. The glass panes are hermetically sealed to retain the gas within the interior space defined by the separate panes of glass and respective spacers. These IG units have a rectangular profile and are generally positioned within door frames and sliding glass doors. 
     Pet doors are utilized to provide access for pets such as cats and dogs to exit and enter homes without the need for an owner to repeatedly open and close doors. Pet doors are commonly known and used. Pet doors are customarily designed for integration with doors of a house. Holes are cut out of the door frame and the pet door is installed in the frame of the door. 
     However, in certain circumstances, where the glass is utilized throughout the majority of the door, such as in a sliding glass door on a patio, the pet door is larger than the frame and hence the frame cannot be cut for installation. You cannot cut the tempered glass in the door or it will shatter. 
     U.S. Pat. No. 7,784,430 illustrates a common solution for installation of a pet door in a sliding patio environment. An independent pane or door section which includes a pet door is positioned adjacent to the regular sliding door pane in sliding frame. While suitable for its intended purpose, this construction does not provide for the insulation benefits of a well sealed sliding door system. 
     Alternatively, U.S. Pat. No. 4,760,872 discloses a pet door for installation in a fixed or moveable glass door or window. This patent discloses that the single pane of glass has been cut for installation of the pet door. The pane is encased in a frame and with the corner cut out; the pet door is adapted for being received within the remaining portion of the frame. While suitable for its intended purpose, such a construction of a pet door is not suitable for an insulated glass unit as the moment the glass is cut, the inert gases will escape. 
     Accordingly, there is a need in the art for a pet door which is integrated with an insulated glass unit to provide the thermal benefits of the insulated glass unit while permitting utilization by a pet. 
     SUMMARY OF THE INVENTION 
     A glass assembly for a dwelling comprises a first pane extending in a first direction and including an outer edge defining an outer periphery and an internal edge defining an internal periphery. A second pane offset from the first pane and extending parallel to the first direction and including an outer edge defining an outer periphery and an internal edge defining an internal periphery. At least one spacer interconnecting the outer edge of the first pane with the outer edge of the second pane and interconnecting the internal edge of the first pane with the internal edge of the second pane defining an enclosed interior. The spacer integrating the internal edges of the first and second pane to define a pet channel of sufficient size to enable a pet to pass from a profile defined by the first pane to a profile defined by the second pane. An inert gas disposed within the enclosed interior. A pet door assembly is also included. The pet door assembly includes a first pet door frame surrounding the internal edge of the first pane; and a second pet door frame surrounding the internal edge of the second pane. The first pet door frame and second pet door define a pet door opening communicating with the pet channel for receiving a pet and enabling a pet to pass from one side of the glass assembly, through the glass assembly, and exiting on the other side of the glass assembly. 
    
    
     
       DESCRIPTION OF THE DRAWINGS 
       The construction designed to carry out the invention will hereinafter be described, together with other features thereof. The invention will be more readily understood from a reading of the following specification and by reference to the accompanying drawings forming a part thereof, wherein an example of the invention is shown and wherein: 
         FIG. 1  is a general view illustrating the insulated glass unit with an integrated pet door according to the present invention. 
         FIG. 2  is an exploded view illustrating the hermetically sealed insulated glass unit in combination with the interior and exterior components of a pet door. 
         FIG. 3  is a perspective view illustrating the hermetically sealed insulated glass unit integrated with the interior and exterior components of a pet door. 
         FIG. 4  is a cross-sectional view of  FIG. 3  illustrating a cross section of the hermetically sealed insulated glass unit integrated with the interior and exterior components of a pet door. 
     
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT 
     The following detailed description is to be read with reference to the drawings, in which like elements in different drawings have been given like reference numerals. The drawings, which are not necessarily to scale, depict selected embodiments and are not intended to limit the scope of the invention. Skilled artisans will recognize that the examples provided in the present disclosure have many suitable alternatives that can be utilized, and which fall within the scope of the invention. 
       FIG. 1  illustrates one example of an insulated glass unit  10  that can be provided in the present invention. The insulated glass unit  10  includes two separated panes of tempered glass encompassed within a hermetically sealed frame  12  with an inert gas such as argon or krypton contained within the interior space defined by the panes and frames. In the embodiment shown in  FIG. 1 , the insulated glass unit  10  is of the sliding door variety. However, the insulated glass unit  10  could also be a door. In both circumstances, the insulated glass unit  10  encompasses a pet door  14  which extends through the glass boundary of the insulated glass unit. The combination of the insulated glass unit  10  and the pet door  14  forms a multi-pane insulated glass unit assembly incorporating a pet door A. 
       FIG. 2  illustrates the components of the multi-pane insulated glass unit assembly incorporating a pet door A according to one embodiment of the present invention. As illustrated, the insulated glass unit  10  includes a first pane  20  and a second pane  22 . Each pane is preferably a mirror image of the other providing for a symmetrical design enabling the incorporation of a pet door into the profile of the respective panes. As shown in  FIG. 2 , each pane includes outer edges; top upper edge  24 , right outer edge  26 , bottom outer edge  28  and left outer edge  30 . In the vicinity of bottom outer edge  28 , the respective panes include an interior right edge  32  and an interior left edge  34  offset from each other defining a pet passage through the profile of the two panes. In the preferred embodiment, a top interior edge  38  is also provided. As shown in  FIG. 1 , insulated glass unit  10  and the various edges are designed for incorporation into an external frame  12 . 
     As shown in  FIG. 2 , first pane  20  and second pane  22  are integrated with respect to each other via a plurality of spacers  50 . In particular, spacers  50  integrated each respective edge of first pane  20  and second pane  22  in a manner that provides for a hermetic seal. In particular spacers  50  include a top upper edge spacer,  52 , a right outer edge spacer,  54 , a bottom outer edge spacer  56  and left outer edge spacer  58  which when integrated with the respective edges of the first and second panes define an external periphery. Of particular importance are interior right edge spacer  60 , interior left edge spacer  62  and upper interior edge spacer  64  which when combined with the respective interior edges of the first and second panes define an internal periphery. The spacers  50  can be of any suitable material. Typically, spacers are filled with or contain desiccant to remove moisture trapped in the gas space during manufacturing, thereby lowering the dew point of the gas in that space, and preventing condensation from forming on surface. In the preferred embodiment, the interior edge spacers are preferably translucent such as glass. Spacer  20  in combination with first pane  20  and second pane  22  define an interior  70  for receiving an inert gas denser than air such as argon or krypton. 
     This construction defines insulated glass unit  10  and enables the inert gas to be retained within the unit while defining pet passage  36  which extends within the profile of the of the insulated glass unit of sufficient size for receiving a pet door. While  FIG. 2  illustrates one possible design of the pet passage  36  and respective interior edges, a lower edge is also possible for defining a fully encircled pet passage. 
     As shown in  FIG. 2 , pet door  14  includes an external pet door member  80  and an internal pet door member  82 . External pet door member  80  includes a frame  84  which defines a pet opening  86  of sufficient size to enable a pet to walk through. Likewise, internal pet door member  82  includes a frame  88  which defines a pet opening  90  of similar size for communicating with the external door pet opening  86 . A closing flap  92  is provided for closing off the pet passage. In particular, the external pet door member frame  84  and internal pet door member frame  88  are sized such that they are wider than the pet passage  36  and may be integrated with insulated glass unit  10  such that the respective frames of the pet door extend around the entire perimeter of the pet passage  36 . As showing in  FIG. 2 , one embodiment of a pet door is constructed such that the external pet door member  80  includes a flange which extends into pet passage  36  and preferably engages the respective interior edges of the insulated glass unit. While mention has been made to the interior and exterior pet door frame components, they are interchangeable and could be positioned either internally or externally. Furthermore, while an interior mating flange is desired, the pet door assembly could consist of frame members only without any internally extending flanges. 
       FIG. 3  illustrates a fully integrated multi-pane insulated glass unit assembly incorporating a pet door. In the preferred embodiment the pet door frame members are carried by the integrated glass unit and affixed utilizing an adhesive or other similar attachment mechanism. As shown in  FIG. 3 , the pet door is “through” the glass enabling the aesthetic properties of the glass door or pane to be enjoyed while maintaining the insulating properties desired and having the convenient benefits of a pet door. A sealant is preferable around the edges of the pet door frame members for providing sufficient weathering protection in the interior of the dwelling. 
       FIG. 4  illustrates a cross-section of the assembly as shown in  FIG. 3 . The top upper edges  24  of first pane  20  and second pane  22  are interconnected with top upper edge spacer  52  and respective bottom outer edge  28  are interconnect with bottom outer edge spacer  56 . Internally, upper interior edge spacer  64  interconnects the respective interior upper edges  38 . In this configuration a pet opening  90  is defined and an insulated glass pane interior  70  maintains inert gas. External pet door member  80  and internal pet door member  82  are shown in an embodiment which includes an internally extending flange  88  which extends into the pet passage  36  for providing a path for an animal to pass. A low emittance coating may be applied to either the first or second pane 
     Thus it may be seen that according to the invention an advantageous design for an insulated glass assembly may be had which provides for the opportunity for a pet to pass through the insulated glass assembly while maintaining the insulating properties of the assembly.