| 摘要 |
PURPOSE:To increase mechanical octane value of an engine without increase in friction loss and unburned mixture concentration by a method wherein the cylinder head and cylinder block are cooled independently and the cylinder head can be cooled more powerfully than the cylinder block. CONSTITUTION:Respective water jackets 4, 5 are provided in the cylinder head 2 and cylinder block 3 independently. The inlet 6 of the water jacket 4 is connected with the radiator 11 via tubings 8, 12 and a water pump 9. On the other hand, the inlet 13 of the water jacket 5 is connected with the outlet of a water pump 18 via tubings 15, 17 and a directional control valve 16, and the outlet 14 is connected with the suction inlet of the water pump 18 via a tubing 19. The tubing 17 mentioned above is connected with the tubing 15 via the directional control valve 16, tubings 20, 22, 24, a heat exchanger 21 and a directional control valve 23. The directional control valves 16, 23 are to be made of, for example, shape memory alloy so as to remain in the states as indicated by the full lines when temperatures of coolant are preset points or below, for example, 80 deg.C or below and 95 deg.C or below respectively. |
