Flange type duct joint assembly

A flange type duct joint assembly to connect the end portions of generally rectangular ducts comprising,

• a plurality of flange portions connected to adjacent flange portions by angular corner pieces to form a generally rectangular frame,
• said flange portions having an upstanding channel shaped leg portion with a front wall and a rear wall forming a longitudinal opening therebetween,
• said flange portions having a duct receiving leg portion with a top wall and a bottom wall, said top wall abutting said bottom wall and arranged to receive an end portion of a duct therebetween, said bottom wall extending angularly from said upstanding channel shaped leg portion front wall,
• said upstanding channel shaped leg portion front wall includes a longitudinally extending inturned rebent portion extending into said longitudinal opening,
• said inturned rebent portion having a tear drop configuration in elevation with an upper leg and a lower leg, said upper and lower legs diverging from each other and extending at acute angles from said upstanding channel shaped leg portion front wall,
• said lower leg extending downwardly toward said duct receiving leg portion bottom wall, said lower leg being spaced from said duct receiving leg portion bottom wall,
• said upper leg and said lower leg each having a first end portion positioned in overlying, abutting relation at said upstanding channel shaped leg portion front wall,
• said upper leg and said lower leg each having a second end portion being connected and positioned closely adjacent to said upstanding channel shaped leg portion rear wall to form a pocket that facilitates sealing engagement of the ends of the respective ducts to said flange portions to minimize air leakage between the ends of the ducts and said flange portions,
• said angular corner pieces each including a body portion and a pair of leg portions connected to said body portion,
• said leg portions being displaced angularly from said body portion and positioned in parallel relation to said body portion so that said body portions of adjacent corner pieces of the assembly are in abutting relation while said adjacent pairs of leg portions are spaced from each other a distance substantially equal to the thickness of said flange portions front wall,
• connecting means extending through adjacent corner pieces for connecting the end portions of the generally rectangular ducts,
• said connecting means being adapted upon tightening to exert a clamping force on said body portions of adjacent corner pieces and to urge adjacent corner pieces toward each other and thereby concentrate the application of sealing forces upon said flange portion front walls, and
• said upstanding channel shaped leg portion having a vertical inner wall intersecting the top wall of said duct receiving leg, said intersection of said respective walls being located at substantially the same elevation as said rebent portion lower leg.