| 摘要 |
PURPOSE:To improve the cooling effect in an exhaust valve having a vacancy extending from the umbrella-like end through the stem therein, with a coolant contained in the vacancy, by providing a member which restrains sinking of the coolant which rises to the upper part of the vacancy. CONSTITUTION:A vacancy 4 is formed from an umbrella-like part 2 through a stem 3 of an exhaust valve 1 which reciprocates in the direction of X-X inside a guide 7 formed in a cylinder head 6 of an internal combustion engine. A coolant such as sodium 5 is supplied inside the vacancy 4. A net 8 is jammed in the upper part of the stem part 3 of the vacancy 4 and acts as a member that restrains the sodium 5 from sinking by trapping the sodium which has risen toward the upper part of the vacancy. The net 8 prolongs a duration that the sodium 5 stays in the cooling part, hence improving the cooling effect. |
