| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To adjust pressure of a cooling water pump suction part becoming minimum pressure in a circuit to optional pressure of head pressure or less when necessary, for setting pressure in a cooling water circuit such as an exhaust gas heat exchanger to predetermined pressure, in an engine cooling water circuit having an exhaust heat recovery unit. <P>SOLUTION: This cooling water circuit includes the exhaust heat recovery unit 37 for supplying engine exhaust heat via engine cooling water, a radiator 18 for radiating the engine exhaust heat via the engine cooling water, the exhaust gas heat exchanger 33 for supplying the engine exhaust heat to the engine cooling water from exhaust gas, and a cooling water pump 32 for circulating the engine cooling water. A pressure loss apparatus 34 is arranged upstream of a cooling water pump suction part 32b, and an orifice is arranged in a communicating passage 50 between the cooling water pump suction part and an atmospheric opening part 20, and the upstream side of the pressure loss apparatus is communicated with the atmospheric opening part, and the atmospheric opening part can be always communicated with the atmosphere. <P>COPYRIGHT: (C)2010,JPO&INPIT</p> |
