COOLING DEVICE OF INTERNAL-COMBUSTION ENGINE FOR VEHICLE, AND CONTROL METHOD

摘要

The present invention relates to a cooling device of an internal-combustion engine for a vehicle, and a control method. The cooling device of the present invention is provided with an electric water pump, a bypass line which bypasses a radiator, and a flow rate control valve which controls the flow rate of cooling water circulating through the bypass line. In a low ambient-temperature condition in which the ambient temperature is lower than a threshold, the flow rate of the cooling water circulating through the bypass line is increased compared with a high ambient-temperature condition in which the ambient temperature is higher than said threshold, thereby increasing the cooling water temperature compared with the high ambient-temperature condition, and the circulating flow rate of the cooling water is increased by increasing the discharge flow rate of the electric water pump compared with the high ambient-temperature condition.