초록 ▼

A controller for electrically actuated engine valves operates in a switching mode to monitor back EMF during periods when the coil drive current is off. Back EMF is used to determine a position of the armature so as to control the armature current to provide for soft seating of the valve reducing va

A controller for electrically actuated engine valves operates in a switching mode to monitor back EMF during periods when the coil drive current is off. Back EMF is used to determine a position of the armature so as to control the armature current to provide for soft seating of the valve reducing valve wear.

대표청구항 ▼

[ I claim:] [1.]1. A controller for an electrically actuable engine valve, the valve having an actuation coil producing a magnetic field to attract a movable armature communicating with a valve head; the controller comprising:a current control circuit receiving a valve actuation signal and a drive c

[ I claim:] [1.]1. A controller for an electrically actuable engine valve, the valve having an actuation coil producing a magnetic field to attract a movable armature communicating with a valve head; the controller comprising:a current control circuit receiving a valve actuation signal and a drive current signal to provide current to the actuation coil when the valve actuation signal is present and as a function of the drive current signal;an armature detector sensing a back EMF resulting from an approach of the movable armature toward the actuation coil; anda soft seat circuit adjusting the drive current signal to the current control circuit during the approach of the armature toward the actuation coil wherein the drive current signal is a function of the back EMF sensed by the armature detector.