Patent ID: 6244230
Filing Date: 2001-06-12
Classification: F01L

Abstract:
A variable valve timing apparatus employed in an engine to vary the valve timing of intake valves or exhaust valves, wherein the engine includes a crankshaft, an intake camshaft for driving the intake valves, an exhaust camshaft for driving the exhaust valves, and a transmission for transmitting rotation between the crankshaft, the intake camshaft, and the exhaust camshaft, wherein the variable valve timing apparatus comprises:a first actuator arranged on only one of the intake camshaft and the exhaust camshaft, wherein the first actuator only adjusts the rotational phase of the camshaft on which the first actuator is arranged relative to the crankshaft; anda second actuator arranged on only the other of the intake camshaft and the exhaust camshaft, wherein the second actuator only adjusts the axial position of the other of the intake camshaft and the exhaust camshaft to adjust the valve lift of the valves driven by the camshaft on which the second actuator is arranged.