| 摘要 |
<p>PROBLEM TO BE SOLVED: To prevent increase in exhaust pressure loss when warming a coolant by recovering the exhaust heat while avoiding the mountability deterioration due to the increase in size of a system.SOLUTION: An exhaust heat recovery system of an engine 1, comprises a refrigerant passage 20 for heat exchange having a first refrigerant circulation system provided between a cooling water outlet of the engine 1 and the entrance side of a water pump 11 for heating the cooling water via a warmer 30 with the exhaust heat and a second refrigerant circulation system for allowing the cooling water to circulate between the warmer 30 and a radiator 35 for radiation, in which the opening/closing control of on/off valves A to E switches-over between the first refrigerant circulation system and the second refrigerant circulation system on a basis of at least an engine water temperature. The warmer 30 is interposed at an exhaust pipe 3 so as to be capable of continuously recovering the exhaust heat during operation of the engine. A continuously stable exhaust gas stream can be ensured without requiring changeover of exhaust passages, accompanied by a pressure loss, between an engine cooling state in that the cooling water is warmed and an engine warm state with no need to heat the cooling water.</p> |
