Abstract: An electromagnetically actuable fuel injector for an internal combustion engine is disclosed having an outer housing, a fuel inlet connector positioned in the upper end portion of the outer housing for reception of fuel therein, and an armature having a valve needle attached thereto and positioned adjacent the fuel inlet connector and spaced therefrom by a working gap. The armature defines a generally elongated central opening to receive fuel flow from the fuel inlet connector and has valve needle attached thereto which interacts with a fixed valve having a fixed valve seat associated with the housing to selectively permit fuel to flow through a valve aperture associated with the fixed valve seat.

Abstract: An improved method for controlling the landing velocity of an armature in an electromechanical actuator, such as a fuel injector, fuel pressure regulator, or engine valve actuator is provided. The position and velocity of an armature during a stroke is dynamically estimated by calculating the inductance and rate of change of inductance of the actuator coil in real-time as the armature moves through its stroke, compensating for non-linear permeability and magnetization effects due to changing gap, temperature, magnetic material properties or magnetic architecture, normalizing the calculated inductance value at the end of a stroke (zero gap), and mapping the value of normalized inductance to correspond to an armature position by an algebraic transformation. Inductance may be used directly as a position variable without mapping it to units of position. Rate of change of inductance may be used as a rate variable without mapping it to units of velocity.

Abstract: An electromagnetically actuable fuel injector for an internal combustion engine is disclosed having an outer housing, a fuel inlet connector positioned in the upper end portion of the outer housing for reception of fuel therein, and an armature having a valve needle attached thereto and positioned adjacent the fuel inlet connector and spaced therefrom by a working gap. The armature defines a generally elongated central opening to receive fuel flow from the fuel inlet connector and has valve needle attached thereto which interacts with a fixed valve having a fixed valve seat associated with the housing to selectively permit fuel to flow through a valve aperture associated with the fixed valve seat.

Abstract: A method is provided to determine a static position of an armature 24 of an electronically controlled solenoid device 10. The method provides an electronically controlled solenoid device having a first stator 14 and a first coil 16 operatively associated with the first stator, a second stator 18 and a second coil 22 operatively associated with the second stator, and an armature 24 mounted for movement between the first and second stators. The armature defines a magnetic circuit with each of the first and second stators and their associated coils. A flux of a magnetic circuit associated with each coil is ramped in a generally linear manner over a period of time. A nominal position of the armature is defined where current in both of the coils is substantially equal. A current slope of each of the coils resulting from the associated ramped flux is observed. An offset of each current slope from the nominal position is indicative of the static position of the armature.

Abstract: An electromagnetically operable fuel injector for a fuel injection system of an internal combustion engine is disclosed having a ferromagnetic core, a magnetic coil at least partially surrounding the ferromagnetic core and an armature magnetically coupled to the magnetic coil and being movably responsive to the magnetic coil. The armature actuates a valve-closing element, which interacts with a fixed valve seat and is movable away from the fixed valve seat of a fuel valve when the magnetic coil is excited. The armature has a generally elongated shape and a generally central opening for reception of fuel from a fuel inlet connector positioned adjacent thereto. The fuel inlet connector extends in a generally longitudinal direction above the armature and defines a central path for fuel to enter the inlet connector and to be directed toward the armature for further passage toward the fixed valve seat.

Abstract: The present invention provides a fuel injector with an armature and a means for biasing the armature toward a first position. A primary coil is wound in a first direction such that, when energized, it develops a magnetic force that opposes the biasing means and causes the armature to move from the first position to a second position. A secondary coil is positioned coaxially with the primary coil. The secondary coil has an at least partially reverse wound portion wound in a second direction opposite the first direction, such that the magnetic field generated by the at least partially reverse wound portion at least partially cancels the magnetic field of the primary coil.

Abstract: The present device provides a fuel injector including a two-input, self-triggering monostable driver circuit for an electromechanical valve is disclosed. Upon receipt of an initiation signal, the driver circuit generates a predetermined current profile in a coil. A current sensing mechanism senses the current flowing through the coil, enabling a current threshold generator to detect a preset peak current threshold state. Upon detection of the preset peak current threshold state, the current threshold generator establishes a new hold current threshold state in the coil. A rapid decay generator forces a rapid transition from peak current to hold current within the coil. The hold current is maintained within preset hysteretic limits until the valve cycle is terminated by removing the initiation signal from the inputs.

Abstract: A method is provided for determining magnetic characteristics of an electrically controlled solenoid. The method includes providing an electronically controlled solenoid having an armature, a stator and a coil operatively associated with the stator. The armature, stator and coil define a magnetic circuit. The armature is spaced from the stator to define an air gap between the armature and the stator. Current to the coil is ramped in a generally linear manner over a period of time to define a known current curve. A resulting rate of change of flux in the magnetic circuit is observed and recorded at certain points along the current curve. In accordance with another aspect of the invention, flux in the magnetic circuit is ramped in a generally linear manner over a period of time to define a known flux curve. A resulting current in the coil is observed and recorded at certain points along the flux curve.

Abstract: A method of controlling velocity of an armature of an electromagnetic actuator as the armature moves from a first position towards a second position is provided. The electromagnetic actuator includes a coil and a core at the second position. The coil generates a magnetic force to cause the armature to move towards and land at the second position. A control method is provided to ensure a near zero velocity landing of the armature in the second position while compensating for non-ideal external influences on the system.

Abstract: A method and apparatus for controlling a heated tip injector having a connector with more than two pins. In one embodiment, the method includes (a) providing a plurality of heated tip injectors each having a coil and an internal heater; (b) maintaining all the internal heaters in an OFF state while the engine is cranking; (c) maintaining an internal beater in an OFF state if any of the coils are ON; and (d) maintaining an internal heater in an ON state if the engine is not cranking and all the internal heater coils are OFF.

Abstract: An electromagnetically operable fuel injector for a gaseous fuel injection system of an internal combustion engine, the injector having a generally longitudinal axis, a ferromagnetic core, a magnetic coil at least partially surrounding the ferromagnetic core, and an armature magnetically coupled to the magnetic coil and being movably responsive to the magnetic coil. The armature actuates a valve closing element in the form of a valve needle which interacts with a fixed valve seat of a fuel valve and is being movable away from the fixed valve seat when the magnetic coil is excited. The armature has a generally elongated shape and a generally central opening for axial reception and passage of gaseous fuel from a fuel inlet connector positioned adjacent thereto. The fuel inlet connector and the armature are adapted to permit at least a first flow path of gaseous fuel between the armature and the magnetic coil as part of a path leading to the fuel valve.

Abstract: A method is provided to control velocity of an armature of a fuel injector as the armature moves from a first position towards a second position. The fuel injector includes a stator core at the second position and a coil is associated with the stator core. The coil, the stator core and the armature define a magnetic circuit. The coil generates a magnetic force to cause the armature to move towards and impact the stator core. The method includes energizing the coil to permit the armature to move towards the stator core. A rate of change of magnetic flux of the magnetic circuit is determined. Closed loop feedback control of the determined rate of change of magnetic flux is used to regulate a rate of magnetic flux by controlling current to the coil so as to control a velocity of the armature upon impact with the stator core.

Abstract: An electromagnetically operable fuel injector, for a gaseous fuel injection system of an internal combustion engine is disclosed, the injector having a generally longitudinal axis, a ferromagnetic core, a magnetic coil at least partially surrounding the ferromagnetic core, and an armature magnetically coupled to the magnetic coil and being movably responsive to the magnetic coil. The armature actuates a valve closing element which interacts with a fixed valve seat of a fuel valve and is movable away from the fixed valve seat when the magnetic coil is excited, the armature having a generally elongated shape and a generally central opening for axial reception and passage of gaseous fuel from a fuel inlet connector positioned adjacent thereto. The fuel inlet connector and the armature are adapted to permit a first flow path of gaseous fuel through a working gap between the fuel inlet connector and the armature and between the armature and the magnetic coil as part of a path leading to the fuel valve.

Abstract: A method of controlling velocity of an armature of an electromagnetic actuator as the armature moves from a first position towards a second position is provided. The electromagnetic actuator includes a coil and a core at the second position. The coil generates a magnetic force to cause the armature to move towards and land at the core. Spring structure acts on the armature to bias the armature away from the second position to a resetting position. The method includes selectively energizing the coil to permit the armature to move at a certain velocity towards the core. A certain voltage corresponding to a voltage across the coil is determined when the armature is approaching the core. The certain voltage corresponds to a rate of change of magnetic flux and is used as a feedback variable to control energy to the coil so as to control a velocity of the armature as the armature moves towards the core. In one embodiment, the certain voltage is a measured terminal voltage of the coil.