Flat tube heat exchanger having corrugated fins with louvers

Claim 1

In a heat exchanger having corrugated fins having a plurality of louvers connected by U-shaped bends and a liquid tube structure having a plurality of flat, parallel, radiating surfaces with the U-shaped bends of said corrugated fins juxtaposed to and in heat-transfer contact with the radiating surfaces; the improvement in which: said louvers are formed from a plurality of substantially parallel fin plates which are normal to said radiating surfaces and have juxtaposed louver-blade-forming portions alternately projected above and below the base plane of each fin plate, thereby forming a plurality of louver blades alternating above and below said base plane; at least in the front part of said louvers, said blades are so arranged that the states of inclination thereof relative to said base plane vary alternately, those above said plane sloping down toward said plane at an angle in the direction of the outlet end and those below said plane sloping up toward said plane at a like angle and in the same direction; and said louver blades have a spacial arrangement such that there are uninterrupted lines of sight from one end to the other, one line of sight being above said base plane and another line of sight being below said base plane.