# US 5,345,743 A · Insulated window assembly with internal muntin bars and method of making same > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 5,345,743 A - Document ID: US5345743A - Status: Granted - Kind: A - Application number: 07/595,996 - Filed: 1990-10-11 - Granted: 1994-09-13 - Earliest claimed: 1990-10-11 - Assignees: Peela Corporation - Inventors: Bruce A. Baier - Web page: https://patentgrep.com/patent/US5345743A ## CPC - E06B 3/6604: {comprising false glazing bars or similar decorations between the panes (connectors therefor E06B3/6675)} - E06B: FIXED OR MOVABLE CLOSURES FOR OPENINGS IN BUILDINGS, VEHICLES, FENCES OR LIKE ENCLOSURES IN GENERAL, e.g. DOORS, WINDOWS, BLINDS, GATES (shades or blinds for greenhouses A01G9/22; curtains A47H; lids for car boots or bonnets B62D25/10; skylights E04B7/18; sunshades, awnings E04F10/00) ## Abstract A true divided look is provided in an insulated two-pane window assembly through use of a resilient silicone foam internal muntin bar grid which is low in thermal conductivity to limit heat transfer between panes and is high in flexibility to allow for bending when forming curved shapes. The grid is secured by adhesive on one side to one pane of glass, thereby allowing natural expansion and contraction of the glass panes. The resilient muntin bar includes the resilient muntin bar being U-shaped with a base from which legs extend which are compressible and adapted to move laterally in response to pressure from the panes due to changing thermal conditions or bonding of external wooden muntin bars to the panes. Movement of the panes toward each other would be limited by bottoming out against the base of the resilient muntin bar. ## Claims ### Claim 1 An insulated window assembly comprising: first and second spaced apart panes of transparent sheet material; a perimeter spacer bar positioned between said panes and extending around the perimeter of said panes and defining two pairs of opposite sides of said window assembly; and an internal muntin bar grid disposed between said first and second spaced apart panes, said muntin bar grid being formed from a silicone foam material which is low in thermal conductivity to limit heat transfer between said first and second spaced apart panes, and is high in flexibility to allow for bending when forming curved shapes. ### Claim 2 (depends on 1) The structure of claim 1 wherein adhesive means secures said muntin bar grid to one of said first and second panes. ### Claim 3 (depends on 2) The structure of claim 2 wherein said adhesive means secures said muntin bar grid to only one of said first and second panes whereby said panes may expand apart without stressing said muntin bar grid and stressing said adhesive means. ### Claim 4 (depends on 1) The structure of claim 1 wherein said muntin bar grid is U-shaped and includes a base and oppositely disposed legs having outer ends positioned closely adjacent one of said first and second panes and with said base being positioned closely adjacent said other of said panes. ### Claim 5 (depends on 4) The structure of claim 4 wherein said oppositely disposed legs of said U-shaped muntin bar are resilient to pressure from said first and second panes. ### Claim 6 (depends on 4) The structure of claim 4 wherein said base portion of said U-shaped muntin bar grid is secured by adhesive means to one of said first and second panes. ### Claim 7 (depends on 5) The structure of claim 5 wherein said ends of said legs adjacent said other of said first and second panes allow unrestricted movement of said other pane away from said legs. ### Claim 8 (depends on 1) The structure of claim 1 wherein said muntin bar grid comprises two component bars closely spaced to appear as a single bar. ### Claim 9 (depends on 8) The structure of claim 8 wherein each of said component bars includes a base and an upstanding leg extending between said first and second panes. ### Claim 10 (depends on 9) The structure of claim 9 wherein said leg has an outside wall in the plane of an outside wall of said base whereby said component bars give the appearance of a single muntin bar. ### Claim 11 An insulated window assembly comprising: first and second spaced apart panes of transparent sheet material; a perimeter spacer bar positioned between said panes and extending around the perimeter of said panes and defining two pairs of opposite sides of said window assembly; an internal muntin bar grid disposed between said first and second spaced apart panes, said muntin bar grid being formed from a nonmetallic material which is low in thermal conductive to limit heat transfer between said first and second spaced apart panes and adhesive means securing said muntin bar grid to only one of said first and second panes whereby said panes may expand apart without stressing said muntin bar grid and stressing said adhesive means. ### Claim 12 An insulated window assembly comprising: first and second spaced apart panes of transparent sheet material; a perimeter spacer bar positioned between said panes and extending around the perimeter of said panes and defining two pairs of opposite sides of said window assembly; an internal muntin bar grid disposed between said first and second spaced apart panes, said muntin bar grid being formed from a silicone foam material which is low in thermal conductivity to limit heat transfer between said first and second spaced apart panes, and is high in flexibility to allow for bending when forming curved shapes, and external wood muntin bars being secured to said first and second panes in superimposed relationship relative to said internal muntin bar grid. ### Claim 13 An insulated window assembly comprising: first and second spaced apart panes of transparent sheet material; a perimeter spacer bar positioned between said panes and extending around the perimeter of said panes and defining two pairs of opposite sides of said window assembly; an internal muntin bar grid disposed between said first and second spaced apart panes, said muntin bar grid being formed from a nonmetallic material which is low in thermal conductivity to limit heat transfer between said first and second spaced apart panes, and is high in flexibility to allow for bending when forming curved shapes, and said muntin bar grid being U-shaped and including a base and oppositely disposed legs having outer ends positioned closely adjacent one of said first and second panes and with said base being positioned closely adjacent said other of said panes, said oppositely disposed legs of said U-shaped muntin bar being resilient to pressure from said first and second panes, said resilient legs being adapted to depress and deflect laterally under pressure from said panes moving towards each other whereby further movement of said panes is limited by said base. ### Claim 14 (depends on 13) The structure of claim 13 wherein said nonmetallic material is foam material.