Abstract: A core plate of a header tank of a heat exchanger has an annular housing groove portion housing a tip part of a tank body and a seal component. The seal component is housed in a housing space formed by the housing groove portion and the tip part of the tank body. The housing groove portion has a bottom wall part which supports the seal component together with the tip part of the tank body, and an outer wall part located at an outer periphery side of the bottom wall part. The outer wall part has at least one discharge part through which liquid is discharged to outside from a clearance between a side surface of the tank body opposing the outer wall part and a lower side of the outer wall part in a stacking direction of tubes.

Abstract: A core plate of a header tank of a heat exchanger has an annular housing groove portion housing a tip part of a tank body and a seal component. The seal component is housed in a housing space formed by the housing groove portion and the tip part of the tank body. The housing groove portion has a bottom wall part which supports the seal component together with the tip part of the tank body, and an outer wall part located at an outer periphery side of the bottom wall part. The outer wall part has at least one discharge part through which liquid is discharged to outside from a clearance between a side surface of the tank body opposing the outer wall part and a lower side of the outer wall part in a stacking direction of tubes.

Abstract: A cooling water circuit system for an engine includes a radiator bypass passage through which cooling water of the engine bypasses a radiator, a heat exchanger disposed in the radiator bypass circuit to perform heat exchange between the cooling water and lubricant oil of an automatic transmission, and a radiator downstream passage through which the cooling water from the radiator flows into the heat exchanger. Further, a flow adjusting unit is disposed at a join portion where the radiator bypass passage and the radiator downstream passage are joined, to adjust a flow ratio between the cooling water flowing from the radiator downstream passage to the heat exchanger and the cooling water flowing from the radiator bypass passage to the heat exchanger. The flow adjusting unit is controlled by a control unit in accordance with the temperature detected by the temperature detection unit.

Abstract: A cooling water circuit system for an engine includes a radiator bypass passage through which cooling water of the engine bypasses a radiator, a heat exchanger disposed in the radiator bypass circuit to perform heat exchange between the cooling water and lubricant oil of an automatic transmission, and a radiator downstream passage through which the cooling water from the radiator flows into the heat exchanger. Further, a flow adjusting unit is disposed at a join portion where the radiator bypass passage and the radiator downstream passage are joined, to adjust a flow ratio between the cooling water flowing from the radiator downstream passage to the heat exchanger and the cooling water flowing from the radiator bypass passage to the heat exchanger. The flow adjusting unit is controlled by a control unit in accordance with the temperature detected by the temperature detection unit.

Abstract: A heat exchanger such as used as an inter cooler for cooling an intake air of an internal combustion engine has an inner fin which is provided within a tube through which heat transfer medium such as an intake air flows. The inner fin has a plurality pairs of a first vertical wall portion and a second vertical wall portions, a first horizontal wall portion connecting an upper end of the first vertical wall portion to an upper end of the second vertical wall portion, and a second horizontal wall portion connecting a lower end of the first vertical wall portion to a lower end of the second vertical wall portion. The inner fin further has a plurality of slits formed from the vertical wall portion side of the first horizontal wall portion via entire length of the vertical wall portion until the vertical wall portion side of the second horizontal wall portion. The fin pitch P, the length L of vertical wall portion between adjacent pair of the slits, and the width S of the slit are as follows.1.6 mm.ltoreq.P.