Pre-charging strategy for fuel injector fast opening
AssigneeVisteon Global Technologies, Inc.
InventorMin Xu
Life of this patent
Estimating the term…
Abstract
Minimizing fuel injector opening time greatly improves fuel efficiency and performance. Pre-charging the fuel injector solenoid is an inexpensive means of reducing opening time. The solenoid is pre-charged to a level that is slightly below a current level that would move an armature located near the solenoid for a known period. A larger current is then applied to the solenoid which moves the armature quickly to an open position. A current is then applied that is less than the pre-charging or valve-opening current to hold the armature in a open position. Finally, all current is removed from the solenoid, allowing the armature to return to a closed position.
Claims15
A fuel injector drive system for use in an internal combustion engine of a vehicle comprising:
- a solenoid;
- a armature mounted adjacent to said solenoid for controlling the amount of fuel entering said internal combustion engine;
- a spring operatively connected to said armature which holds said armature in a closed position when a magnetic force generated by said solenoid is not sufficient to overcome a biasing force of said spring;
- a circuit electrically connected to said solenoid which selectively provides a pre-charging current with an amperage nominally below an amperage necessary to move said armature for a period sufficient to plateau the pre-charging current level, a valve-opening current with an amperage much above an amperage necessary to move the armature, for a period sufficient to ensure full opening, and a holding current with an amperage nominally above an amperage necessary for said armature to return to said closed position for a period sufficient to provide said engine with fuel;
- a controller in electrical communication with said circuit for controlling time and duration of the application of said currents by said circuit;
- and
- a voltage source in electric communication with said circuitry for providing said circuit various voltages to obtain the said various current levels within the solenoid coil.
A method of controlling a current in a solenoid to move an armature of a fuel injector between an opening and a closing position in a fuel injector drive system comprising the steps of:
- applying a pre-charging current to said solenoid at a level that does not move the armature for a period sufficient to plateau the pre-charging current;
- applying a valve-opening current, which is much greater than said pre-charging current and has an upper limit sufficient to fully move said armature to an open position, for a period sufficient to ensure full opening;
- applying a valve-holding current, which is less than said valve-opening current and said pre-charging current for a period sufficient to provide said internal combustion engine with fuel;
- removing current, allowing said armature to return to said closing position.
An apparatus for controlling a current in a solenoid to move an armature of a fuel injector between an opening and a closing position in a fuel injector drive system, said apparatus comprising:
- a means for applying a pre-charging current to said solenoid at a level that does not move said armature for a period sufficient to plateau said pre-charging current;
- a means for applying a valve-opening current which is much greater than said pre-charging current and has an upper limit sufficient to fully move said armature to an open position, for a period sufficient to provide said internal combustion engine with fuel;
- and
- a means for removing current, allowing said armature to return to said closing position.
Dependencies are inferred from the claim text.