| 摘要 |
A rotary valve system for controlling the fuel charge inlet and the exhaust outlet of a four-stroke petrol engine comprises a single domed rotary valve A located in the combustion chamber and forming the hemi-spherical cylinder roof. The rotary valve A has preferably three openings D to coincide with a set of three port openings on the corresponding cylinder head B. As the valve rotates about its stem F the openings D uncover the next set of three port openings in sequence. Position I corresponds with the inlet of fuel/air charge, position C. to seal the chamber for compression and to uncover three spark plugs (Z, fig.6) and position E coincides with the exhaust ports. This stepping sequence follows the conventional four-stroke cycle, and the timing of the valve rotation is managed by a digitally controlled stepping motor arrangement J. The cylinder head dome B may be cast or machined with port tubes attached to achieve smooth port surfaces, and to mould port channels (K, Fig 10) such that the fuel charge will have a turbulence bias so it will swish into the combustion chamber to better mix the air and fuel. |
