MULTI CYLINDER DIESEL ENGINE WITH VARIABLE DRIVE VALVE

摘要

PROBLEM TO BE SOLVED: To reduce harmful exhaust gas, to solve the problem at low- temperature start producing so-called 'blue smoke' in a warm-up process after starting at a low temperature, and to improve performance and fuel cost. SOLUTION: A cam controlling an intake valve has specific shape. Each intake valve is opened in a usual exhaust stroke of an engine and recycling (EGR) of exhaust gas in the engine is achieved according to the shape. It is based on the fact that a part of exhaust gas move from a cylinder to an intake port in the usual exhaust stroke, returns to the cylinder in the next intake stroke afterward, while a part of the exhaust gas having already moved to an exhaust port returns to the cylinder in the intake stroke by the additional opening of the exhaust valve. As a result, the exhaust gas returning to the cylinder and filled again is used in combustion in the next cycle.