Patent ID: 8167028

Claim:
A heat exchanger comprising: a pair of header tanks; a plurality of tubes extending between said pair of header tanks; and a plurality of fins extending in a length direction between said pair of header tanks; wherein each of said plurality of fins is defined by a strip of material formed into a plurality of U-shaped corrugations extending in said length direction, each U-shaped corrugation defining a first leg, a second leg and a planar crest extending between the first and second legs; each first and second leg of each corrugation defining a width direction, each corrugation defines a plurality of sections extending in the width direction, each section being separated from an adjacent section in the length direction of the fin by a single slit through said strip of material configured to form a louver, said slit defining an upstream edge of one section and a downstream edge of an adjacent section, wherein no two sections of each corrugation are aligned in the same plane; each of said single slits extending into a planar trough and the planar crest of said U-shaped corrugation but not through said planar trough or said planar crest; and each single slit in the first leg being aligned with a respective single slit in the second leg of each corrugation in the length direction to define a planar portion between the aligned single slits.