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US 7,295,417 B2Granted
Electromagnetic valve actuation with series connected electromagnet coils
AssigneeFord Global Technologies, LLC
InventorAllan J. Kotwicki
Life of this patent
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AssigneeFord Global Technologies, LLC
InventorAllan J. Kotwicki
Estimating the term…
Systems and methods for valve actuation use series-connected coils of upper and lower electromagnets acting as electromagnetic generators that attempt to maintain a constant magnetic flux, while their forces are essentially independent. A valve controller initiates valve actuation by reducing holding force of the holding electromagnet. As spring force begins to move an armature away from the holding electromagnet, the associated coil generates a voltage that attempts to maintain constant flux. This generated voltage causes a large increase in current that essentially transfers the flux to the other on-coming coil, which attracts and holds the armature against its associated spring force to open or close the valve. The internal voltage generated inside the two coils operates even if the coils are supplied with zero external voltage (shorted) to transfer stored energy directly between the coils. Energy may be transferred indirectly using an energy storage device.
A method for controlling an internal combustion engine having a plurality of cylinders each having at least one intake and exhaust valve with at least one of the valves being operated by an electromagnetic actuator having an armature coupled to the valve and traveling between first and second electromagnets to open and close the valve in response to a control signal from an actuator control, the first electromagnet having a first coil connected in series to a second coil of the second electromagnet, the method comprising:
A method for actuating an intake or exhaust valve of an internal combustion engine using an electromagnetic valve actuator having an armature connected to the valve and traveling across a gap between first and second electromagnets having corresponding first and second coils connected in series to open and close the valve, the method comprising:
A system for actuating an intake or exhaust valve of an internal combustion engine, the system comprising:
Dependencies are inferred from the claim text.