| 摘要 |
PURPOSE:To make it possible to always obtain a suitable volume of engine cooling air by operating an opening/closing mechanism for an air-intake port with the use of a changing section having a shape which varies in dependence upon the temperature of an engine. CONSTITUTION:In an air-intake port opening/closing device 9, when the temperature of an engine is low, a bimetal 14 to which the temperature of engine oil is transmitted through a heat pipe 18 shrinks since the temperature of the engine oil is low. Accordingly, the bimetal 14 causes an air-intake port cover 10 to slide along the peripheral surface of a cooling fan cover 7 so that an air shut-off wall 13 closes an air-intake port 8. As result, the opening area of the air-intake port 8 is decreased so as to prevent the engine from being excessively cooled. Meanwhile, when the temperature of the engine is high, the bimetal 14 expands so as to align an air communication port 12 with the air-intake port 8. Accordingly, the opening area of the air-intake port 8 is increased to prevent the engine from being overheated. Thus, the opening area of the intake-air port 8 may be adjusted in accordance with a variation in temperature of the engine. |
