Variable valve timing reciprocating IC engine - has auxiliary valves of rotary type in inlets with timing set according to engine loading

摘要

The engine has pistons (2) reciprocating in cylinders (1). Each cylinder has poppet type inlet and exhaust valves (6,8), with a throttle in the inlet. A rotating plug type valve (10) is provided in the inlet passage (9) to each cylinder, driven from the crankshaft to open the inlet periodically. The valve timing can be varied in relation to that of the inlet valve, so that when the inlet is throttled at part load the inlets are open for a shorter time. This improves part load efficiency.