Abstract:
An improved insulated glass including a spacer unit and a pair of glazing panels bonded to opposite sides thereof. The spacer unit includes a peripheral spacer portion and a muntin portion within the spacer portion. The spacer unit is a one-piece, injection-molded unit, and consequently the spacer portion and the muntin portion form an inseparable integrated whole.

Description:
BACKGROUND OF THE INVENTION 
     The present invention relates to insulated glass and more particularly to spacers and muntins used within insulated glass. 
     Insulated glass is well known and widely used in a variety of applications such as doorlights. Insulated glass includes a pair of panes or panels of glass separated by a spacer. Typically, the spacer is aluminum and extends around the perimeter of the assembly, defining a space between the glass panes. The panels are adhered and sealed to the spacer to secure the assembly together. A desiccant is included within the spacer to absorb moisture within the insulated glass space. The space may be filled with an inert gas to enhance the insulation effect. 
     Often a muntin or grille also is included within the insulated glass. Typically, such an “internal” muntin is aluminum and is positioned between the panes within the confines of the spacer to provide an aesthetically pleasing appearance to the window. Such a construction is illustrated, for example, in U.S. Pat. No. 3,308,593, issued Mar. 14, 1967 to Smith and entitled “Panel For Inclusion In A Unit To Be Installed In A Building Opening.” Unfortunately, the inclusion of the muntin is relatively expensive and labor intensive. Care must be taken during the manufacture of the muntin and the assembly of the insulated glass to ensure that the muntin is properly fabricated and positioned within the assembly. Aesthetics are important to the commercial success of the insulated glass. 
     SUMMARY OF THE INVENTION 
     The aforementioned problems are overcome in the present invention wherein a spacer unit is provided that is a one-piece, integral unit including both a spacer portion and a muntin portion. The spacer unit may be fabricated, for example, of injection-molded plastic. The spacer portion is continuous and extends around the entire perimeter of the insulated glass. The muntin portion is integral with the spacer. The glass panels are adhered to the spacer portion. The muntin portion is suspended within the space between the glass panels, and the muntin portion is spaced from the glass panels. 
     The present invention produces an insulated glass with an internal muntin that is simpler and less expensive than prior art insulated glass. It also provides improved aesthetic and functional benefits. The seal of the glass panels to the spacer is enhanced at the corner because the spacer portion is continuous at the corners. The spacing of the muntin portion from the glass panels reduces “rattling.” Molding the spacer and muntin of plastic and spacing the muntins from the glass reduces thermal transmission through the insulated glass. Because the product includes a plastic spacer, it is less likely to generate condensation than prior art assemblies using aluminum spacers. Further, because the muntin is integral with the spacer, assembly joints are eliminated to enhance aesthetics. 
     These and other objects, advantages, and features of the invention will be more fully understood and appreciated by reference to the detailed description of the preferred embodiment and the drawings. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a perspective exploded view of the insulated glass of the present invention shown in conjunction with a doorlight frame; 
     FIG. 2 is a perspective view of the insulated glass of the present invention; 
     FIG. 3 is a sectional view taken along line III—III in FIG. 2; 
     FIG. 4 is a sectional view similar to FIG. 3 showing an alternative embodiment of the muntin cross-section; and 
     FIG. 5 is a sectional view taken along line V—V in FIG.  2 . 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     An insulated glass (also referred to as IG) constructed in accordance with a preferred embodiment of the invention is illustrated in the drawings and generally designated  10 . The insulated glass  10  includes a spacer unit  12  and a pair of glass panes or panels  14  and  16  adhered to opposite sides thereof. The spacer unit  12  includes a peripheral spacer portion  20  and an internal muntin portion  30 . The panels  14  and  16  are adhered to the spacer portion  20  and are spaced from the muntin portion  30 . 
     FIG. 1 illustrates the insulated glass  10  in conjunction with a pair of doorlight frame halves  17  and  18 . The frame halves  17  and  18  are generally well known to those skilled in the art and therefore will not be described in detail. For example, the frame halves can be constructed in accordance with U.S. Pat. No. 5,644,881 issued Jul. 8, 1997 to Albert J. Neilly and entitled “Window Frame with Integral Connectors,” the disclosure of which is incorporated by reference. 
     The glass panes or panels  14  and  16  also are generally well known to those skilled in the art and can be any known glazing panel. For example, the glass used in the described embodiment of the invention is a fully tempered glass that is ⅛ inch thick, such as that sold by AFG of Kingsport, Tenn. Other materials can and are substituted for the glass panels. Other suitable materials include polycarbonates, acrylics, plastics, and virtually any other translucent or transparent material. 
     The spacer unit  12  is new to the present invention and includes a spacer portion  20  and a muntin portion  30 . The spacer portion  20  includes a body  21  having a pair of opposite channels  22  and  23  to which the panels  14  and  16  are adhered. The cross section of the spacer portion  20  is uniform throughout the entire perimeter of the spacer unit  12 . The channels  22  and  23  are slightly concave to receive sealant between the spacer portion  20  and the panels  14  and  16 . In the preferred embodiment, the body portion  21  maintains the panels  14  and  16  a fixed distance apart of approximately ¾ inch. The spacing may vary depending on the particular application. The spacer portion  20  includes an interior face  25  and an exterior face  24 . The interior face  25  defines a pair of grooves  26  and  27 , which extend the full perimeter of the spacer portion  20  to receive a desiccant or desiccant matrix  40 . 
     The muntin or grille portion  30  includes one or more horizontal muntins  31  and/or one or more vertical muntins  32 . The muntins  31  and  32  visually divide the insulated glass  10  into evenly sized smaller panes. However, the muntin could be constructed to visually divide the area into any desired pattern. As illustrated in FIG. 3, all of the muntins  31  and  32  are generally rectangular in cross section and are spaced from the glass panels  14  and  16  so that the panels do not and cannot engage the muntins. This construction prevents the muntins from rattling against the glass when the assembly is subjected to lateral forces, such as when a door opens or shuts. As disclosed, the depth D of the muntins is ⅜ inch. 
     The cross section of the muntins can be varied as desired, for example, for strength and aesthetics. FIG. 4 illustrates an alternative cross section for the muntins  32 ′. This cross section is useful when the muntins are intended to simulate the appearance of wood moldings. The alternative muntin  32 ′ also is spaced from both of the glass panels  14  and  16  and as a depth generally the same as that of muntin  32 . 
     Assembly and Operation 
     The assembly of the insulated glass  10  is perhaps best illustrated in FIG.  5 . As a preliminary step, a caulk-type desiccant matrix  40  is applied to the spacer unit  12  in either or both of the grooves  26  and  27 . The currently preferred desiccant is that sold under the designation Adco Therm Desiccant Matrix by Adco of Michigan Center, Mich. Other appropriate desiccants and desiccant matrices will be known to those skilled in the art. The desiccant matrix  40  may be applied in either, both, or neither of the grooves  26  and  27 ; and the desiccant may extend for all or any portion of the perimeter of the spacer portion  20 . It also is foreseen that the desiccant could be molded into the plastic of which the spacer  12  is fabricated. 
     Butyl adhesive or sealant  50  is applied to the faces  22  and  23  of the spacer portion  20 . The butyl  50  extends around the entire perimeter of the spacer portion  20 . The adhesive in the preferred embodiment is that sold under the designation 2000HS by Adco of Michigan Center, Mich. Other appropriate sealants are and will be known to those skilled in the art. 
     The panels  14  and  16  with the spacer unit  12  are laid up as a sandwich. Optionally, an edge sealant (not shown) such as polysulfide can be applied to the edge of the insulated glass  10 . The entire assembly is run through pinch rollers or other appropriate equipment to improve proper adhesion of the components and to ensure consistent thickness of the glass assemblies. 
     Because the spacer unit  12  is fabricated of an integral, one-piece construction, the assembly has several advantages. First, the spacer portion  20  is continuous around the entire perimeter of the insulated glass  10 , including in the corners. This eliminates the requirement of corner keys between individual spacer elements as are conventional in the art. Second, the muntin portion  30  is integrally and automatically provided within the insulated glass  10  as the spacer unit  12  is put into position. The positions of all muntins  31  and  32  are properly provided, and the muntins are not fragile as in prior constructions. Accordingly, the possibility of misaligning or damaging the muntin during assembly is virtually eliminated. Also, the absence of fabrication joints between crossing muntins  31  and  32  and between the muntin portion  30  and the spacer portion  20  enhances the aesthetics. Third, the spacing of the muntin portion  30  from the panels  14  and  16  ensures that the muntins do not rattle against the panes if the insulated glass is subjected to a lateral force, for example, as might occur when a window or door is slammed open or shut. Fourth, because the spacer unit  12  is plastic, thermal transmission is reduced. In summary, the insulated glass  10  with the spacer unit  12  is easier to assemble, has fewer components, is less subject to damage or failure, is more aesthetically pleasing, and provides improved thermal transmission properties than previously known insulated glass with aluminum spacers and internal muntins. 
     The above description is that of a preferred embodiment of the invention. Various alterations and changes can be made without departing from the spirit and broader aspects of the invention as defined in the appended claims, which are to be interpreted in accordance with the principles of patent law, including the doctrine of equivalents.