Patent ID: 7073467
Filing Date: 2006-07-11
Classification: F01M,F01P

Abstract:
1. A cooling water circuit system for an engine, comprising: a radiator which cools cooling water of the engine; a radiator water passage through which cooling water circulates between the radiator and the engine; a radiator bypass passage through which the cooling water from the engine bypasses the radiator; a heat exchanger disposed in the radiator bypass circuit to perform heat exchange between the cooling water and lubricant oil of an automatic transmission of the engine; a radiator downstream passage through which the cooling water, after passing through the radiator and before passing into the engine, flows into the heat exchanger, the radiator downstream passage being connected to the radiator water passage at a downstream side of the radiator and an upstream side of the heat exchanger; a flow adjusting unit disposed at a join portion where the radiator bypass passage and the radiator downstream passage are joined, to adjust a flow ratio of the cooling water flowing from the radiator downstream passage to the heat exchanger to the cooling water flowing from the radiator bypass passage to the heat exchanger; a temperature detection unit which detects a temperature of the lubricant oil having passed through the heat exchanger; and a control unit which controls the flow adjusting unit in accordance with the temperature detected by the temperature detection unit.