| ign="center"> | | | | the duct work in each position where it is desired to |
| A sheet metal stamping forming an air duct for use in | | | | connect the take-off section. |
| heating and cooling systems and the like. The | | | | While the above described systems are known in the |
| stamping has a generally rectangular shaped body | | | | art, it yet remains necessary to provide a totally |
| portion and a protruding tongue portion extending | | | | standardized system which is readily assembled, |
| from at least one side thereof. The stamping is | | | | relatively inexpensive and which utilizes standardized |
| foldable along its end edges and the tongue portion | | | | parts. The system of the presentinvention is |
| whereby two such stampings may be cooperatively | | | | designed for the least restriction of air from the |
| engageable with a pair of side panels to form an air | | | | heating or cooling system through the main ducts and |
| duct section having an inlet, outlet and a diverter or | | | | into the take-off or leader pipes. A generally standard |
| secondary outlet formed by the tongue portions. The | | | | shaped fitting based on a modular construction |
| tongue portions are adapted for connection to | | | | concept is provided having astandard length and a |
| standard conventional take-off fittings. | | | | variable width based on a preestablished range of |
| Sheet metal duct section having an inlet and outlet | | | | sizes. A single fitting which provides top and bottom |
| comprising in combination:a prestamped upper and | | | | plates of a duct system is adapted for utilization with |
| lower spaced panel interconnected by spaced side | | | | side panels and includes at least one outwardly |
| panels, at least one side panel being shorter in length | | | | extending tongue memberthereon forming a diverter |
| than said upper and lower panels and defining an | | | | or take-off section on which any of a large number |
| opening through which at least a portion of flow | | | | of standard take-off fittings may be attached. Since |
| through said inlet isdiverted, said upper and lower | | | | the system is based on a standard length for each |
| panels having end edges and a central body portion | | | | preformed fitting, layout is considerably simplified, and |
| extending the length and width of said duct section | | | | in fact quickand relatively accurate calculations to |
| from said inlet to said outlet and formed tongue | | | | determine the total length of the system may readily |
| portions extending laterally beyond said shortened | | | | be made simply by counting as for example, in a |
| side, said stampingsbeing folded along their end edges | | | | residential building, the number of floor joists to lay |
| and cooperatively engaged with said side panels to | | | | out the entire system. In the preferred embodiment |
| form the air duct section, and said tongue portions | | | | ofthe invention, each panel section is fabricated from |
| cooperatively forming a diverter outlet to divert flow | | | | a stamping and has a lip or other fastening means |
| through said inlet from said outlet, said duct having | | | | formed at the ends and edges thereof. Each section |
| adiminishing cross section from said inlet to said | | | | has a standard length of 16 inches or multiples |
| outlet. | | | | thereof which correspond to the conventionalspacing |
| The prior art has recognized the advantages of a | | | | between floor joists. |
| main conduit or trunk duct having reductions in cross | | | | The standardized system of the present invention is |
| sectional area along its length to provide generally | | | | applicable to generally all heating installations and |
| equal air flow at each outlet. Such systems are | | | | specifically adapted for home heating situations. The |
| however, relatively expensive andaccordingly have | | | | expense of custom-made installations is reduced. |
| not found commercial acceptance. Partially | | | | Each section formed in accordancewith the present |
| prefabricated air duct fittings have been proposed | | | | invention has an inlet side and a diminished outlet side |
| for use in heating and ventilating systems, however, | | | | thereby providing, when assembled, a heating system |
| in each case a great number of separate component | | | | in which the main trunk line is decreased at each |
| parts are required including top andbottom panels, | | | | take-off junction to thus proportion and reduce the |
| take-off sections, side panels and the like. In some of | | | | cross sectional area ofthe main trunk line along its |
| prior art systems the top and bottom panels and the | | | | length. |
| side walls are provided with spaced longitudinally | | | | Basically, the invention provides a sheet metal duct |
| extending marginal tabs and corresponding slots. The | | | | section having an inlet and an outlet and includes |
| tabs, when inserted inthe slots are bent over to | | | | prestamped upper and lower spaced panels |
| secure the plate and wall together in a rigid assembly. | | | | interconnected by spaced side panels. At least one |
| Such systems, however, require careful handling since | | | | side panel is shorter in length than the upperand |
| the tabs are easily deformed during such handling. | | | | lower panels thereby defining an opening through |
| Additionally, if an ar tight seal is required, the tabs | | | | which at least a portion of the flow of air through |
| and slotmust be sealed with putty, or similar sealing | | | | the inlet portion is diverted. The upper and lower |
| substances. | | | | panels are prestamped and have a central body |
| In another system known in the prior art, | | | | portion extending the length and width of the |
| prefabricated assembled components of the duct | | | | ductfrom the inlet to the outlet and a tongue portion |
| system are provided. Each component is reduced in | | | | is formed thereon extending laterally beyond the |
| cross sectional size from the previous adjacent | | | | shortened side. The tongue portion is folded for |
| component whereby they may be nested for | | | | connection to a diverter or take-off duct section. |
| shipment andstorage. In the above systems, | | | | Finally, a secondary side panel joins the |
| however, separate provision must be made for the | | | | tongueportions to form the diverter duct. |
| connection of take-off ducts and other fittings to | | | | The many advantages of the present metal stamping |
| registers or wall stacks or the like. In these cases | | | | invention will become apparent to those skilled in the |
| either elaborate tab and slot combinations must be | | | | art upon reading the following description with |
| prefabricated orotherwise provided or in the case of | | | | reference to the accompanying drawings illustrating |
| the nestable preassembly an opening must be cut in | | | | the preferred embodiment of the invention. |