Heat exchanger

A heat exchanger comprising:

• a plurality of tube elements laminated alternately with fins over a plurality of levels:
• end plates provided at either end in the direction of lamination;
• a passage plate at the side of one of said end plates, in which a supply passage and discharge passage for heat exchanging medium are formed;
• an intake pipe and an outlet pipe connected to said supply passage and said discharge passage, respectively, of said passage plate;
• wherein said supply passage and said discharge passage of said passage plate have sufficient lengths to allow said intake pipe and said outlet pipe to be connected at arbitrary positions;
• wherein tube elements, each of which is provided with a pair of tanks on one side and also with a U-shaped heat exchanging medium passage communicating between said pair of tanks, are laminated alternately with fins over a plurality of levels;
• wherein tanks in adjoining tube elements are interconnected to form two tank groups extending in the direction of said lamination, one of said tank groups having a partition at approximately a center thereof such that said one of said tank groups is divided into two portions, the other of said tank groups having no partition:
• wherein said supply passage communicates via a heat exchanging medium supply pipe with one of said portions in said one of said tank groups, said one of said portions being further away than the other of said portions from said passage plate, and said discharge passage communicating with the other of said portions of said one of said tank groups;
• and
• wherein said heat exchanger has a so-called 4-pass flow pattern with tanks only on one side, in which,
• said heat exchanging medium is supplied to said heat exchanging medium supply pipe from said supply passage to enter approximately half of said tube elements, then enters the remaining tube elements after passing through said U-shaped heat exchanging medium passages of said tube elements and finally reaches said discharge passage after passing through the U-shaped heat exchanging medium passages of said remaining tube elements.