Finned heat exchanger composed of pressure welded louvered passageway panels

摘要

805,630. Making heat exchangers. REYNOLDS METALS CO. March 21, 1957, No. 9351/57. Classes 83 (2) and 83 (4). Angular bending; shearing.-A method of making a heat exchanger, e.g. a condenser unit for an air-conditioning system, comprises integrally bonding together a pair of metal sheets at least one of which is formed to provide between the sheets a plurality of parallel passages interconnected at their ends and spaced by bonded areas, slitting the bonded areas to form a plurality of slats each incorporating a passageway and twisting the slats to lie at an angle to the sheets to form a louvred plate. Two flat aluminium sheets, Fig. 1, are integrally bonded together by pressure-welding with stop-weld interposed to define a pattern of unbonded areas, the latter being inflated by fluid pressure to form passageways 2 in the panel 1, spaced by bonded areas 3 and interconnected at the ends by inlet and outlet headers 4, 7 respectively and by cross-over headers 5, 6 connecting the interposed group " M " of passageways with the inlet and outlet groups " A " and " Z " respectively. An eccentric-operated upper bar 13, Fig. 6, then shears the first bonded area 3 along a line 9, preferably centrally situated between adjacent passageways 2 and on the same stroke twists the portion 3 to the position shown in Fig. 6, the panel 1 being clamped between U- shaped holding dies 11, 12. On moving the plate to the right a further bonded area is sheared along a similar line and both bars 13 act simultaneously during the cutting stroke to twist the passageway 2 with fins formed from the adjacent bonded areas out of the plane of the panel 1 to form louvres. A number of louvred panels so formed are mounted face-to-face and brazed or welded to side-walls, the passageways being connected to transverse inlet and outlet fittings. The finned passageways or tubes of adjacent panels may be staggered and the fins may lie at opposite angles of inclination, Fig. 8. In a modification the formation of the louvres may be carried out prior to expanding the unbonded areas into passageways. U.S.A. Specification 2,662,273 is referred to.