| 摘要 |
PURPOSE:To design to secure a state of no fear for seizure or burnout even in a high-power engine, by installing a hollow section composed of closed multistages along the axial center line of a valve stem in the within of a valve head and the valve stem of a valve. CONSTITUTION:A series of closed multistage-hollow sections 20a-20n are formed up along the axial center line of a vlave head 19a and a valve stem 19b of a valve 19 and a fluidic heat medium is poured into a part of the hollow cubic contents in time of high-load running. With this, heat being transmitted from a solid surface of the valve head 19a to the fluidic heat medium 21 is progressively transmitted upward to heat mediums 21a and 21n so far liquefied in the hollow section 20a-20n and thereby cooling of the valve 19 is sufficiently achieved even at an engine high-load region, so that the need of overhauling caused by burnout or seizure of the valve 19 is thus obviated. |
