Cooling device for engine

Abstract

An engine cooling device is provided, which uses a fewer number of ducts for coolant circulation to reduce cost and weight and to make the duct layout easy, and which improves the durability of a differential pressure valve. In the engine cooling device in which a coolant is circulated by a water pump 4 through a coolant circulation flow path 9 at least including a heater circulation flow path 7 that circulates the coolant between a cooling jacket 1 provided at least to one of a cylinder head and a cylinder block of the engine and a heater core 6 , a bypass flow path 8 that communicates the cooling jacket 1 with a portion of the heater circulation flow path 7 downstream of the heater core 6 is provided, and a differential pressure valve 11 that opens when fluid pressure on the side of the cooling jacket 1 exceeds a predetermined value is disposed at a point of exit of the coolant from the cooling jacket 1 to the bypass flow path 8.

1 . An engine cooling device, comprising: a coolant circulation flow path at least including a heater circulation flow path that circulates a coolant between a cooling jacket provided at least to one of a cylinder head and a cylinder block of an engine and a heater core; a water pump; and a coolant that is circulated by the water pump through the coolant circulation flow path, wherein
 the engine cooling device further comprises: a bypass flow path that communicates the cooling jacket with a portion of the heater circulation flow path downstream of the heater core; and a differential pressure valve that opens when a fluid pressure on the side of the cooling jacket exceeds a predetermined value and that is disposed at a point of exit of the coolant from the cooling jacket to the bypass flow path.   
     
     
         2 . The engine cooling device according to  claim 1 , wherein the bypass flow path is connected crosswise to a linear duct portion of the heater circulation flow path downstream of the heater core.