| 摘要 |
PURPOSE:To control the temperature of cooling water to the optimum depending on the load upon an engine, by integrating a changeover valve for shifting the cooling water from the cooling water outlet port of the engine to a by-pass or to a radiator, with a restrictor valve for adjusting the quantity of the cooling water to the radiator. CONSTITUTION:A first valve 67 for shifting the direction of cooling water is provided between the cooling water outlet port of an engine or an inlet port 53 communicating with a cylinder head and a first outlet port 51 communicating with a by-pass. A second valve 69 for adjusting the quantity of the cooling water to a second outlet port 55 communicating with the inlet port of a radiator is integrated with the first valve 67 by a transmission rod 65a. The valves 67, 69 are driven by a diaphragm 61 which moves up or down depending on negative pressure applied through a negative pressure port 57. The magnitude of the negative pressure is controlled depending on the temperature of the cooling water in a cylinder and the cylinder head and the load upon the engine so that the magnitude is maximum at the warm-up of the engine and decreases with the rise in the water temperature. |
