Flange type duct joint assembly and seal arrangement therefor

A joint assembly for connecting the ends of a pair of generally rectangular sheet metal duct sections includes a pair of frame members secured to each other and connected to the respective duct end sections. The frame members each include four flange portions. Each flange portion has an upstanding channel shaped leg portion and an angularly extending duct receiving leg portion.

A corner piece connects adjacent flange portions and extends into the channel portions of the upstanding leg portions to form the generally rectangular frame. The end portions of the ducts are inserted into longitudinal openings of the duct receiving leg portions. A flowing type gasket material is positioned in a longitudinal pocket of each flange. The end of each duct wall partially displaces the gasket material so that the gasket material extrudes outwardly around the duct wall and between the ends of the flange portion and the corner piece.

The surface of the corner piece flange portion is displaced from the front vertical wall of the upstanding channel shaped leg portion so that the edge of the duct extends beyond the flange portion and penetrates an outside gasket member positioned on the upstanding channel shaped leg portion and the corner piece. This provides an effective seal to prevent air within the duct from flowing around the end of the duct and between the outer surface of the duct and the surface of the flange portion of the corner piece.

Claims

I claim:

1. A corner piece for connecting a pair of duct connecting flange members comprising,a corner section with a pair of legs extending angularly therefrom,said corner section and said legs having a common front planar surface portion and a common rear planar surface portion,said legs arranged to extend into said duct connecting flange members to form a generally rectangular duct frame for connection to a duct end portion,said corner section having an offset corner portion displaced rearwardly from said common front planar surface portion, and said corner section offset corner portion and said corner section front planar surface being operable to permit a corner edge portion of the duct end portion positioned between the end portions of adjacent duct connecting flange members toproject beyond said offset corner portion into abutting relation with an external gasket means and said corner section front planar surface in abutting relation with said gasket to seal the corner edge portion of the duct.

2. A corner piece for connecting a pair of duct connecting flange members as set forth in claim 1 in which,said offset corner portion has a generally L-shaped configuration with opposite end portions, and said offset corner portion arranged to be spaced above a duct connecting flange duct receiving portion bottom wall.

3. A corner piece for connecting a pair of duct connecting flange members as set forth in claim 1 in which,said offset corner portion has a generally L-shaped configuration defined by a front surface and a rear surface forming an edge portion therebetween, and said offset corner portion edge portion positioned rearwardly of said common front planar surface portion.

4. A corner piece for connecting a pair of duct connecting flange members comprising,a corner section with a pair of legs extending angularly therefrom,said corner section and said legs having a common front planar surface portion and a common rear planar surface portion,said corner section having a corner portion,a flange portion extending from said corner section corner portion, said flange portion having an end portion displaced rearwardly from said common front planar surface portion, and said corner section front planar surface and said flange portion end portion being operable to permit a corner edge portion of a duct end portion positioned between the end portions of adjacent duct connecting flange members to project beyondsaid flange end portion into abutting relation with an external gasket means and said corner section front planar surface in abutting relation with said gasket means to seal the corner edge portion of the duct.

5. A corner piece for connecting a pair of duct connecting flange members as set forth in claim 4 in which,said flange portion has a generally L-shaped configuration with opposite end portions, and said flange portion end portion arranged to be spaced above a duct connecting flange receiving portion bottom wall.

6. A corner piece for connecting a pair of duct connecting flange members comprising,a corner section having a front surface,a pair of legs extending angularly from said corner section,said corner section having a corner portion with a flange portion having an L-shaped edge portion,said flange portion having a front sealing surface arranged to abut an external gasket means to seal the corner portion of the duct, and said flange portion L-shaped edge portion being offset at an angle less than 90° from said corner section front surface so that said L-shaped edge extends rearwardly in a direction from said corner section front surface to said cornersection rear surface.

7. A corner piece for connecting a pair of duct connecting flange members as set forth in claim 6 in which,said flange portion offset L-shaped edge extends along a curved path rearwardly from said corner section front surface.

8. A corner piece for connecting a pair of duct connecting flange members as set forth in claim 6 in which,said pair of legs each has a front surface and a rear surface,said corner section front surface and said legs front surfaces having portions positioned in a common plane to form a common front planar surface, and said corner section rear surface and said legs rear surfaces having portions positioned in a common plane to form a common rear planar surface.

9. A corner piece for connecting a pair of duct connecting flange members as set forth in claim 8 in which,said flange portion offset L-shaped edge is displaced rearwardly from said common front planar surface.