Abstract: A multi-tube heat exchanger includes a pair of tanks and a plurality of heat transfer tubes fluidly interconnected between the tanks, wherein each heat transfer tube has an engaging portion only at a first end portion engaging a wall of a first tank of the pair of tanks and a relatively movable portion at a second end portion capable of moving in an axial direction of the tube relative to a wall of the second tank. Such a structure helps ensure proper tube positioning and spacing while bowing or deformation of the heat transfer tubes is appropriately prevented at the time of heating and brazing.

Abstract: The present invention is directed to a heat exchanger. The heat exchanger comprises a pair of header tanks and a plurality of pipe members connecting the pair of header tanks in fluid communication. Each of the pipe member includes a pair of fin portions which diametrically project from an outer peripheral surface thereof. The fin portion extends along the longitudinal axis of the pipe member. The pipe member further includes a pair of limiting elements which are formed at a top and bottom end portions of the pipe member, respectively. One of the pair of limiting elements limits an insertion of the top end portion of the pipe member into a bottom portion of the upper header tank, so that no boundary contact line is created between the top end of the fin portions and the lower surface of the bottom portion of the upper header tank.

Abstract: A heat exchanger comprises a first tank and a second tank spaced vertically from the first tank. The first tank includes a first partition disposed therein to divide the first tank into a first number of chambers, wherein the first number of chambers is at least two and has respectively an inlet to allow the heat transfer medium to enter the heat exchanger and an outlet to allow the heat transfer medium to exit the heat exchanger. The second tank includes a second partition disposed therein to divide the second tank into a second number of chambers, wherein the second number of chambers is preferably one less than the first number of chambers. The first tank and the second tank respectively include a concave surface horizontally formed on walls of the tanks, wherein one end of each of the first and second partitions respectively insert into each of the concave surfaces for preventing overturn of the partitions during assembly of the tanks.