METHODS AND APPARATUS TO USE ENGINE VALVES AS BOTH INTAKE AND EXHAUST VALVES

摘要

Methods and apparatus to selectively use engine valves (24) as both intake and exhaust valves and to selectively operate the engine as a 2 cycle or as a 4 cycle engine. In a disclosed embodiment, the intake valves and the exhaust valves are manifolded together through a small manifold, with the manifold being connectable to the intake manifold or the exhaust manifold through two-way valves (26, 28). In preferably a camless engine, the engine valves may be controlled to operate the intake valves as intake valves only or to operate as both intake valves and exhaust valves, and to operate the exhaust valves as exhaust valves only or to operate the exhaust valves as both intake valves and exhaust valves. Exemplary embodiments are disclosed.