| 摘要 |
The invention relates to a water-air heat exchanger of aluminium or an aluminium alloy for motor vehicles, in particular a heater heat exchanger or engine radiator, having a two-pass (passage, duct) or multi-pass arrangement of rows of parallel flat tubes (2) which are soldered to one another via zigzag plates (4), and having at least one tank (cooling-water tank, cooling-water reservoir) (6) connecting in a communicating fashion to one group of ends of flat tubes (2), in which a partition (30) divides an inlet chamber provided with an inlet (32) from an outlet chamber provided with an outlet (34) and whose tube plate (sheet) (8) has slots into which the ends of the flat tubes are inserted in a soldered fashion against the tube plate (8). It is provided in this design that the flat tubes (2) themselves are designed at least in a two-pass fashion by means of at least one partition (36) extending in the longitudinal direction. Between neighbouring oppositely directed passes, in a connecting region (40) at the ends of the flat tubes (2) remote from the tank (6), the partition (36) is respectively cut out over a length along which the adjacent oppositely directed passes communicate. The partition (36) is formed by shaping a sheet-metal part forming the flat tube (2). In the connecting region (40) where the adjacent oppositely directed passes communicate, communication is unrestricted, or is at most reduced only by two wall thicknesses of the flat tube (2). Dents on one or both sides are distributed in the manner of a grid along the oppositely directed passes over the wall of the flat tubes (2) and are dimensioned in addition to the respective partition (36) as spacers for the two flat sides of the respective flat tube (2). <IMAGE> |
