| 摘要 |
PURPOSE:To enlarge the diameters of valve head and consequently enhance the suction and exhaust efficiency by a structure wherein suction valves and exhaust valves are located the nearest to each other as much as a pair of adjacent valves do not interfere with each other at the maximum valve opening time of the suction and exhaust valves. CONSTITUTION:Suction valves 3 and exhaust valves 4 are radially arranged with a center of a point, which lies on the center axis of a cylinder 5 at the semi- spherical combustion chamber 2 of a cylinder head 1. A pair of the suction valves 3 are located in the nearest distance (a') to each other as much as they do not interfere with each other at the maximum opening time of the valves 3 on the center line (a), which bisects the vertical angle of an equilateral triangle consisting in conncecting a point A on the center axis of the cylinder 5 as a vertex with the centers of the valves 3 as the remaining verticles. Similarly, a pair of exhaust valves 4 are located in the distance (b') and furthermore a pair of the suction valve 3 and the exhaust valve 4 in the distance (c') also. In such a manner as mentioned above, the diameters of the respective valve head can be made in its maximum within the combustion chamber, the space within which is limited and consequently the suction and exhaust efficiency can be enhanced. |
