Valve timing control for vehicle IC engine

摘要

The camshaft (12) is uncoupled from the crankshaft drive by a solenoid operated clutch (20) when valve overlap is required. The other end of the camshaft has a gear (38) which is coupled to one of two planetary gears (32,34) when a reversible electric servo motor (24) is operated. This controls the phase and speed of the camshaft without any complex mechanical gearing. For a twin camshaft one of the shafts is fitted with the servo drive option. The planetary support is spring loaded into the neutral position to return the camshaft drive back to standard when the special control mode is switched off.