ENGINE COOLING DEVICE

PROBLEM TO BE SOLVED: To provide an engine cooling device capable of quickly implementing cooling of cooling water even when an engine suddenly changes from a low load state to a high load state in a state that the cooling water is not supplied to a radiator.SOLUTION: An engine cooling device 100 includes an electric water pump 1 capable of controlling a discharge flow rate of cooling water for cooling an engine 101, a radiator 2 for cooling the cooling water, a cooling water flow channel 7a in which the radiator 2 is disposed and the cooling water can be circulated, a cooling water flow channel 7b which is disposed in parallel with the cooling water flow channel 7a and in which the cooling water can be circulated, and a differential pressure valve 5 disposed between the electric water pump 1 and the radiator 2, and opened and closed according to differential pressure ΔP(=P1-P2) between a pressure P2 of the cooling water at an electric water pump 1 side and a pressure P1 of the cooling water at a radiator 2 side.SELECTED DRAWING: Figure 1 【課題】ラジエータに冷却水が供給されない状態において、エンジンが低負荷状態から高負荷状態に急激に変化した場合にも、冷却水の冷却を迅速に行うことが可能なエンジン冷却装置を提供する。【解決手段】このエンジン冷却装置１００は、エンジン１０１を冷却する冷却水の吐出流量を制御可能な電動ウォータポンプ１と、冷却水を冷却するラジエータ２と、ラジエータ２が設けられ、冷却水が流通可能な冷却水流路７ａと、冷却水流路７ａに対して並列に設けられ、冷却水が流通可能な冷却水流路７ｂと、電動ウォータポンプ１とラジエータ２との間に設けられ、電動ウォータポンプ１側の冷却水の圧力Ｐ２とラジエータ２側の冷却水の圧力Ｐ１との差圧△Ｐ（＝Ｐ１−Ｐ２）に応じて開閉される差圧弁５と、を備える。【選択図】図１