| 摘要 |
<P>PROBLEM TO BE SOLVED: To suppress decrease in temperature of cooling water in an engine when there is a heater request during engine warm-up, without using a flow control valve of an electronic control system. <P>SOLUTION: Electric water pump 20 is driven when there is a heater request or the temperature of cooling water is higher than a valve-opening temperature Th2, and is stopped when there is no heater request and the temperature of the cooling water is equal to or lower than the valve-opening temperature Th2. A bypass flow passage 115 bypassing a radiator thermostat 70 is connected to a heater circuit 102 at an upstream side of the radiator thermostat 70. A heater thermostat 80 is connected to the connection part. The heater thermostat 80 is switched so that the cooling water flows to a bypass flow passage 115 when the temperature of the cooling water is equal to or lower than a switching temperature Th1, and is switched so that the cooling water flows to a radiator thermostat 70 side when the temperature of the cooling water is higher than the switching temperature Th1. <P>COPYRIGHT: (C)2012,JPO&INPIT |
