Rectangular duct

Abstract

Longitudinal rectangular ducting 20 for use in HVAC systems is composed of a longitudinal top wall 22 of a desired length and constructed from thin gauge material, for example, from coil stock. The ducting 20 includes a mirror image bottom wall 24 which can be constructed similarly or identically to the top wall 22. The ducting 20 further includes side walls 26 and 28 vertically spanning the outer edge portions of the top and bottom walls 22 and 24. The top, bottom and side walls all having longitudinal edge portions. The longitudinal side edge portions of the first and second wall members deformed to define a standing pocket seam for receiving the side edge portions of the third and/or fourth longitudinal members therein.

The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows: 
     
         1 . Longitudinal HVAC ducting of rectangular or square interior cross section, comprising:
 first and second longitudinal wall members in spaced parallel relationship to each other, the first and second wall members having longitudinal side edge portions extending there along;   third and fourth longitudinal wall members in spaced parallel relationship to each other and disposed transversely to the first and second wall members, the third and fourth wall members having side edge portions engaged with the side edge portions of the first and second wall members to cooperatively form HVAC ducting of a rectangular or square interior cross-section shape; and   the longitudinal side edge portions of the first and second wall members deformed to define a standing pocket seam for receiving the side edge portions of the third and/or fourth longitudinal members therein, the standing pocket seams extending outwardly of the rectangular or square cross-sectional interior ducting shape defined by the first, second, third, and fourth wall members.   
     
     
         2 . The longitudinal HVAC ducting of  claim 1 , wherein the standing pocket seams comprises the side edge portions of the first and second wall members doubled over on itself. 
     
     
         3 . The longitudinal HVAC ducting of  claim 2 , wherein:
 the first and second wall members have outer surfaces; and   the standing pocket seams extend outwardly of the exterior surfaces of the first and second wall members.   
     
     
         4 . The longitudinal HVAC ducting according to  claim 3 , wherein the standing pocket seams of the first and second wall members extend transversely to the outer surfaces of the first and second wall members. 
     
     
         5 . The longitudinal HVAC ducting according to  claim 4 , wherein:
 the standing pocket seams define a height extending from the outer surfaces of the first and second wall members; and   the standing pocket seams are deformed in a direction laterally to the height of the standing pocket seams.   
     
     
         6 . The longitudinal HVAC ducting according to  claim 3 , wherein:
 the standing pocket seams define a height extending from the outer surfaces of the first and second wall members; and   the standing pocket seams, with the edge portions of the third and fourth wall members disposed therein, are deformed in a direction laterally to the height of the standing pocket seams.   
     
     
         7 . The longitudinal HVAC ducting according to  claim 6 , wherein the standing pocket seams are deformed laterally to overlie the exterior of the first and second wall members. 
     
     
         8 . The longitudinal HVAC ducting according to  claim 6 , wherein the standing pocket seams are deformed to overlie the exterior of the third and fourth wall members. 
     
     
         9 . A method of forming longitudinal HVAC ducting of a square or rectangular interior cross section, comprising:
 forming standing pocket seams along the side edges of first lengths of thin gauge metallic material, the standing pocket seams defining pocket openings leading into the standing seam pockets, and a closed standing seam pocket base;   engaging the edges of second lengths of thin gauge metallic material into the standing seam pockets of a pair of the first lengths of metallic material through the pocket openings, the first pair of lengths of metallic material in opposing spaced relationship to each other and oriented so that the pocket openings can receive the edges of the second lengths of metallic material; and   closing the openings of the standing pocket seams against the edges of the second lengths of metallic materials engaged within the standing seam pockets to trap the edges of the second lengths of metallic material within the standing steam pockets and thereby form longitudinal HVAC ducting in square or rectangular interior cross-sectional shape.   
     
     
         10 . The method of  claim 9 , further comprising forming the standing pocket seams by doubling over on itself the side edge portions of the first lengths of thin gauge metallic material. 
     
     
         11 . The method of  claim 9 , wherein forming the standing pocket seams to extend outwardly from the exterior surfaces of the first lengths of thin gauge metallic material. 
     
     
         12 . The method of  claim 11 , comprising forming the standing pocket seams to extend transversely outwardly from the outer surfaces of the first lengths of thin gauge metallic material. 
     
     
         13 . The method of  claim 9 , further comprising deforming the pocket seams, with the edges of the second lengths of metallic material engaged therein, laterally to overlie either the first lengths of thin gauge metallic material or the second lengths of thin gauge metallic material. 
     
     
         14 . Longitudinal HVAC ducting of rectangular or square cross section, comprising first and second longitudinal wall structures, each wall structure comprising:
 first and second integral wall sections disposed transversely to each other from a corner to define edge portions extending along the margins of the first and second wall sections distal from the corner; and   a standing pocket seam formed along the edge portion of one of the first and second wall sections,   wherein the two wall structures are positioned so that the edge portion of one of the first and second wall sections of each wall structure engages within the standing pocket seam formed in the other of the first and second wall structures, whereby the engaged first and second wall structures cooperatively define HVAC ducting of rectangular or square cross section.   
     
     
         15 . The longitudinal HVAC ducting of  claim 14 , wherein the standing pocket seams comprises the edge portions of the first or second wall sections doubled over on itself. 
     
     
         16 . The longitudinal HVAC ducting of  claim 15 , wherein:
 the first and second wall structures have outer surfaces; and   the standing pocket seams extend outwardly from the outer surfaces of the first and second wall structures.   
     
     
         17 . The longitudinal HVAC ducting of  claim 16 , wherein the standing pocket seams of the first and second wall structures extend transversely to the outer surfaces of the first and second wall structures. 
     
     
         18 . The longitudinal HVAC ducting according to  claim 17 , wherein:
 the standing pocket seams define a height extending from the outer surfaces of the first and second wall structures; and   the standing pocket seams are deformed in a direction laterally to the height of the standing pocket seams.   
     
     
         19 . The longitudinal HVAC ducting according to  claim 14 , wherein:
 the standing pocket seams define a height extending from the outer surfaces of the first and second wall structures; and   the standing pocket seams with the edge portions of the first and second wall section of the corresponding first and second wall structure disposed therein, are deformed in a direction laterally to the height of the standing pocket seams.   
     
     
         20 . The longitudinal HVAC ducting according to  claim 19 , wherein the standing pocket seams are deformed laterally to overlie the exterior of either the first or second wall structures.