Patent ID: 7063135

Claim:
A heat exchanger comprising: a plurality of tubes internally having tube-inside flow-through bores; a first header pipe comprising: a first partition wall that is internally formed; a first pipe-inside flow-through bore portion that is internally formed and divided into two regions by the first partition wall; and a first tube insertion bore portion formed on a first area of a side wall in slit shapes to accommodate first end portions of the tubes; a second header pipe comprising: a second partition wall that is internally formed; a second pipe-inside flow-through bore portion that is internally formed and divided into two regions by the second partition wall; and a second tube insertion bore portion formed on a first area of a side wall in slit shapes to accommodate second end portions of the tubes; a first connector bore portion formed on the side wall of the first header pipe at a second area opposing to the first area and on the first partition wall at an area opposing to the second area, and opening to the two regions of the first pipe-inside flow-though bore portion; a second connector bore portion formed on the side wall of the second header pipe at a second area opposing to the first area and on the second partition wall at an area opposing to the second area, and opening to the two regions of the second pipe-inside flow-though bore portion; an inlet connector block having one end portion accommodated in the first connector bore portion and permitting coolant to flow through the first pipe-inside flow-through bore portion; and an outlet connector block having one end portion accommodated in the second connector bore portion and permitting the coolant to flow out through the second pipe-inside flow-through bore portion wherein the distal end surface of the end portion of the inlet connector block is closed, and the side wall of the end portion of the inlet connector block has a plurality of bore portions.