| 摘要 |
PURPOSE:To enhance the cooling performance of a cylinder within its portion near its exhaust hole, by expanding that portion of the inside of its cylinder head which is close to the exhaust hole, and providing on the tip face of the expanded portion an exit for cooling water to which a water hose communicated with a radiator is connected. CONSTITUTION:An engine 1 is mounted on the frame 11 of a vehicle body in such a manner that the axis of its cylinder 8 tilts running direction of the vehicle. A pump forces water cooled by a radiator 2 to circulated through the assembly in the following order: a hose 6 the water jacket of the cylinder 8 the water jacket 9 of its cylinder head 3 an exit 4 for cooling water a hose 5 a radiator 2. In this case, the ceiling 91 of the water jacket 9 is sloped in the direction of the exit 4 for the cooling water while being made higher than a horizontal face, and, as a result of it, that portion 93 of the water jacket 9 which is close to an exhaust hole 19 is formed into an expanded portion. The exhaust-hole 19 side of the cylinder 8 is therefore cooled more than its inlet-port 18 side. |
