PURPOSE: To make uniform the circulation resistance of a passing fluid to be cooled so as to improve the heat exchange by forming inner fins into a plurality of consecutive rectangular projection lines at intervals having the same length in the circumferential directions of inner and outer cylinders, and deviating the positions of the continuous rectangular projection lines circumferentially by a length half the length of the rectangular projection.
CONSTITUTION: In an oil cooler 4 a fluid passage 22 is formed by the inner surface of an outer cylinder 8 and the outer surface of an inner cylinder 10, and inner fins 12 are arranged for causing a turbulent flow phenomenon in an operating oil flowing within the fluid passage 22 and for improving the cooling function. In the inner fins 12, ceiling portions 213 and connecting portions 214 are located at intervals of the same length, and two contiguous rectangular projection lines are arranged so that they are located at positions different from each other by half of the length in the line direction. The operating oil flows along the fluid passage 22 toward an outlet port 16. In accordance there with, while the operating oil carries out heat exchange with water for cooling an engine radiator, an effective flow is generated by the inner fins 12 and thus the cooling effect is improved.
NAKAMURA KATSUNORI
NAGARA TOSHIO
HAMASHIMA MITSUHARU
| JPS5126936B2 | 1976-08-10 | |||
| JPS5628472U | 1981-03-17 |