| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an engine cooling apparatus that achieves an increase in a circulation flow rate of cooling water in a low/medium rotation region while suppressing cavitation in a high rotation region. <P>SOLUTION: The engine cooling apparatus includes: a main cooling water circuit A that circulates the cooling water between an engine 1 and a radiator 2; a branch provided between the engine 1 and the radiator 2; a thermostat 4; a temperature detector 9; a first bypass flow passage 53; a part between the engine 1 and the branch; a second bypass flow passage 54; a control valve 6; a bypass convergence portion 8; a water pump 7; a valve opening controller 10; and an engine rotation speed detector 11. When the temperature of the cooling water is equal to or lower than a predetermined temperature, the first bypass flow passage 53 is set in a circulation state in which the cooling water flows, when the temperature of the cooling water is equal to or higher than the predetermined temperature, the first bypass flow passage 53 is set in a non-circulation state in which the cooling water does not flow, when the engine rotation speed is equal to or lower than a predetermined rotation speed, the control valve 6 is controlled to a fully open state, and when the engine rotation speed is equal to or higher than the predetermined rotation speed, the opening of the control valve is controlled in a fully closed direction from the fully open state. <P>COPYRIGHT: (C)2012,JPO&INPIT |
