Patent ID: 7143824

Claim:
A heat exchanger suitable for use as a charge air cooler for a motor vehicle, comprising at least one header tank with at least one chamber for distributing and/or collecting a flowing medium; and with at least one tube bundle comprising tubes which are connected in a communicating manner to the at least one chamber, the at least one chamber having a tube plate with orifices, into which the tubes of the tube bundle are inserted, wherein at least one of said tubes has an at least double-walled construction having a first wall and a second wall in a region which is inserted in an orifice of the tube plate, wherein an inner surface of the first wall bears over at least a substantial portion of its area against an outer surface of the second wall, and wherein said inner surface and said outer surface are brazed to one another over a partial area along the substantial portion of the area in which they bear against one another.