FIG. 1 is a fragmentary, exploded perspective view of a flange type duct joint assembly for connecting the end portions of a pair of ducts, illustrating a plurality of angular corner pieces for connecting adjacent flange portions to form a framefor receiving the end portions of the ducts.
FIG. 2 is an enlarged perspective view of an angular corner piece and adjacent flange portions.
FIG. 3 is a perspective view of a corner of the end of a duct with the flange portions connected thereto and the corner piece connecting the adjacent flange portions.
FIG. 4 is a fragmentary perspective view of a corner of the end portion of a duct sealingly connected to a pair of adjacent flanges connected by a corner piece, illustrating the edge of the duct extending beyond a flange portion of the cornerpiece. A deformable gasket material in the flanges is shown extruded from the end of one flange but is omitted from the end of the other flange for purposes of illustration only to more clearly show the relationship between the end of the flange, theflange of the corner piece, and the end of the duct.
FIG. 5 is a perspective view of an angular corner piece, illustrating a rearwardly displaced or curved flange portion extending from the inner corner of the corner piece.
FIG. 6 is a perspective view of the opposite face of the angular corner piece shown in FIG. 5, illustrating the configuration of the rearwardly displaced or curved flange portion of the corner piece.
FIG. 7 is a fragmentary perspective view of a corner piece, illustrating the rearwardly displaced or curved flange portion.
FIG. 8 is a fragmentary sectional view of the end portion of the duct abutting the front wall of an upstanding channel shaped leg portion of the flange and penetrating the gasket member positioned on the flange and the corner piece, illustratingthe flange portion of the corner piece curved or displaced rearwardly from the front wall of the channel shaped leg portion.
FIG. 9 is a fragmentary sectional view of the end portions of a pair of ducts connected by the duct joint assembly of the present invention, illustrating the flanges secured to the ducts with the flanges abutting a gasket therebetween.
FIG. 10 is a sectional view of a corner piece taken along the lines X--X of FIG. 7, illustrating the configuration of a leg of the corner piece and the curved or displaced flange portion of the corner piece.
FIG. 11 is a sectional view of a corner piece taken along lines XI--XI of FIG. 7, illustrating the configuration of a corner piece.
Referring to the drawings and particularly to flange. 1-4, there is illustrated the end potion of a pair of duct sections generally designated by the numeral 10 in which each duct 10 has a generally rectangular configuration with an upper duct wall12, a lower duct wall 14, and a pair of vertical duct sidewalls 16 and 18. The ducts 10 are formed in the rectangular configuration illustrated in flange. 1 with a longitudinally extending sealed corner joint 20 between the lower duct wall 14 and thesidewall 16.
As illustrated in flange. 3, the duct upper wall 12 and the duct sidewall 18 terminates in end portions having corner portions with corner edge portions 22 and 24. It should be understood, although not shown, that the other duct walls 14 and 16terminate in similar end portions so that the end portions of the duct 10 extend along a plane transverse to the longitudinal axis of the duct 10.
Each of the ducts 10 preferably is fabricated from galvanized sheet material and may have various thicknesses. For example, commercial grade 20 gauge duct has a thickness of between 0.906 and 1.106 millimeters. The galvanized surface of theduct walls also provides a relatively irregular surface so that the thickness of the sheet metal forming the duct 10 is not uniform along the duct end portions.
The end portions of the pair of ducts 10 are secured to each other by a pair of frame members generally designated by the numeral 26. The frame members 26 are similar in construction and are secured to the ends of adjacent duct sections and areconnected to each other by bolts 25 and nuts 27, shown in FIG. 1 as will be described later in greater detail. Each frame 26 is formed by a plurality of duct connecting flanges that extend outwardly from the duct wall end portion and include an upperflange portion 28, a lower flange portion 30 and a pair of side flange portions 32 and 34. The configuration of the flange portions 28-34 are identical and are preferably cut to a preselected length from an elongated sheet metal strip that has been rollformed into the flange configuration illustrated in the drawings. Throughout the specification, the flange portions 28 and 34 and the connections therebetween will be described in detail; however, it should be understood that the other flange portionsare similarly connected to the duct end portions and to each other.
The flange portion 28 is illustrated in detail in FIGS. 2, 3, 4, 8 and 9. The flange 28 has an upstanding channel shaped corner piece receiving leg portion or upstanding corner piece receiving portion generally designated by the numeral 36 witha front wall 38 connected to a rear wall 40 by a generally horizontal top wall 42. A shoulder 43 is formed between the walls 40 and 42 and is adapted to receive a longitudinal clip 41 illustrated in FIG. 9. Extending laterally at substantially a rightangle from the upstanding channel shaped leg portion 36 is a duct receiving leg portion or duct receiving portion generally designated by the numeral 44 which has a bottom wall 46 and a top wall 48. The top wall 48 has an upturned lip portion 50 topermit the end wall of the duct to slide between the respective walls 46 and 48 so that the duct end wall is frictionally engaged between adjacent surfaces of the flange walls 46 and 48.