| 摘要 |
<p>PROBLEM TO BE SOLVED: To prevent fastening of a valve element by freezing, and to quickly switch flow of exhaust air from a bypass passage to a main passage by quickly opening the valve element in a closed state, when an engine is accelerated.SOLUTION: An exhaust heat recovery device includes a main passage 11 in which an exhaust air flowing in exhaust passage 3 flows, a bypass passage 12 where exhaust air flows while bypassing the main passage 11, a heat exchange portion 13 disposed in adjacent to the bypass passage 12 to allow cooling water 4 to flow therein, so that heat is exchanged between the exhaust air flowing in the bypass passage 12 and the cooling water 4, a valve element 14 opened and closed to selectively switch the flow of exhaust air flowing in the exhaust passage 3 between the main passage 11 and the bypass passage 12, a heat-sensitive main actuator 15 for driving the valve element 14 to be opened from a closed state by sensing the heat higher than a prescribed high temperature of the cooling water, and a heat-sensitive sub-actuator 16 operated when an atmospheric temperature becomes a prescribed low temperature to keep the valve element 14 in a slightly opened state.</p> |
