| 摘要 |
PROBLEM TO BE SOLVED: To provide an engine cooling device capable of increasing a flow rate of cooling water passing through a radiator in good timing according to necessity.SOLUTION: An engine cooling device includes: a first flow channel 1 in which cooling water is circulated through a radiator 3; a second flow channel 2 in which the cooling water is circulated while bypassing the radiator 3; a confluent portion and a confluent passage where a downstream part with respect to the radiator 3, of the first flow channel 1 and the second flow channel 2 join together, and communicate with an engine A; a circulation pump 5 for allowing the cooling water in the confluent passage to flow back to the engine A; a thermostat valve including a temperature-sensitive portion heated by the cooling water of the confluent portion, and a valving element for opening and closing a confluent part to the confluent portion of the first flow channel 1 according to a heating state of the temperature-sensitive portion; a bypass flow channel 12 branched from the downstream of the radiator 3, of the first flow channel 1 and communicated with the confluent passage while bypassing the thermostat valve; a bypass valve 9 capable of opening and closing the bypass flow channel 12; and a control portion 6 for controlling opening/closing motion of the bypass valve 9. |
