| 摘要 |
PURPOSE:To improve the fuel consumption in case of low loading and prevent generation of knocking during transfer to high loading by controlling the circulation of the cooling water for internal-combustion engine according to the temperature of the cooling water and the loading state while delaying the ignition timing in case of high loading at a temperature of the cooling water above the prescribed level. CONSTITUTION:The wax part 23 of a thermal vacuum valve 21 is formed in a cooling- water circulation passage 13, and communication and interception between the first negative-pressure passage 34 and the negative pressure chamber 18 of a cooling-water control valve 15 and between the negative pressure chamber 36 of a vacuum tank 35 and the negative pressure chamber 48 of an ignition- timing changing mechanism 45 are switched over. When the temperature of the cooling water is below a certain value, the ports 24 and 31 and the ports 29 and 31 of a valve 21 are shut-off, and a valve 15 is closed, so delay of ignition angle is not generated. When the temperature of the cooling-water is above a certain value or below a certain value, each port is allowed to communicate, the valve 15 is opened and closed according to the load, and the ignition angle is delayed in case of high loading. When the temperature of the cooling-water is above a prescribed value, an air port 30 is opened, and valve 15 is released. |
