An electromagnetic actuator includes a fixed body, a moving part forming a magnetic core of the actuator and being movable in translation with respect to the fixed body between a retracted position and a deployed position, a magnetic piece forming a permanent magnet adjusted to generate a first magnetic force holding the moving part in the retracted position, and a coil adjusted to engender a second magnetic force opposed to the first magnetic force when the coil is supplied with an electrical excitation current. The moving part includes one or more notches formed in a body of the moving part.

A yoke is provided with a notch, notched from two points P1 and P2 on a circumference forming a sleeve-side insertion hole toward the outside of the circumference, the notch having a minimum distance between the points P1 and P2 as a width W and the distance from a straight line linking the points P1 and P2 in a direction orthogonal to the straight line as a length L. The width W of the notch is set on the basis of a target attraction force for attracting a plunger, the attraction force increasing with an increase in the width W, and the length L of the notch is greater than or equal to a prescribed length Ld where the attraction force increasing with an increase in the length L becomes constant at the target attraction force in the set width W irrespective of an increase in the length L.

A fuel injector for an internal combustion engine of a motor vehicle. The fuel injector including the following: (a) a pole piece, (b) an armature which can be moved along a movement axis, (c) a coil and (d) a permanent magnet, wherein the movable armature has at least one electrically insulating element which is designed to reduce eddy currents in the armature, and wherein the permanent magnet is fitted such that it generates a magnetic field which produces a force which acts on the armature in the direction of the pole piece. The invention also describes a method for ascertaining a position of a movable armature in a fuel injector and also an engine controller.

A yoke is provided with a notch, notched from two points P1 and P2 on a circumference forming a sleeve-side insertion hole toward the outside of the circumference, the notch having a minimum distance between the points P1 and P2 as a width W and the distance from a straight line linking the points P1 and P2 in a direction orthogonal to the straight line as a length L. The width W of the notch is set on the basis of a target attraction force for attracting a plunger, the attraction force increasing with an increase in the width W, and the length L of the notch is greater than or equal to a prescribed length Ld where the attraction force increasing with an increase in the length L becomes constant at the target attraction force in the set width W irrespective of an increase in the length L.

The present disclosure relates to internal combustion engines. Various embodiments may include an electromagnetic injection valve, particularly a solenoid type fluid injection valve for automotive applications. For example, an electromagnetic injection valve may include: an inlet tube; a valve body having a longitudinal axis and a cavity in which a valve needle moves; an upper magnetic ring press-fitted with the inlet tube or the valve body; a lower magnetic ring press-fitted with the valve body; and a housing part surrounding an electromagnetic actuator unit for moving the valve needle. The lower magnetic ring is positioned on the valve body in such a way that an upper side of the lower magnetic ring is in close contact with an underside of the housing part. The electromagnetic actuator unit abuts the upper magnetic ring and the lower magnetic ring on opposite axial sides. The housing part and/or the lower magnetic ring comprises a cut extending along the axis.

The present disclosure provides an electromagnetic actuator that drives an armature by an electromagnetic force. The electromagnetic actuator includes a stator, a coil, and an insulator. The stator is formed of a magnetic material and has a cylindrical portion. The coil is disposed outside of the stator. The coil generates a magnetic field when being energized. The insulator is disposed in a particular region of the stator facing the coil in a radial direction. The insulator extends partially along the stator in a circumferential direction and suppresses a current flowing through the stator in the circumferential direction. The stator is continuously formed entirely along the circumferential direction by the magnetic material.

An electromagnetic actuator includes a fixed body, a moving part forming a magnetic core of the actuator and being movable in translation with respect to the fixed body between a retracted position and a deployed position, a magnetic piece forming a permanent magnet adjusted to generate a first magnetic force holding the moving part in the retracted position, and a coil adjusted to engender a second magnetic force opposed to the first magnetic force when the coil is supplied with an electrical excitation current. The moving part includes one or more notches formed in a body of the moving part.

The present disclosure relates to internal combustion engines. Various embodiments may include an electromagnetic injection valve, particularly a solenoid type fluid injection valve for automotive applications. For example, an electromagnetic injection valve may include: an inlet tube; a valve body having a longitudinal axis and a cavity in which a valve needle moves; an upper magnetic ring press-fitted with the inlet tube or the valve body; a lower magnetic ring press-fitted with the valve body; and a housing part surrounding an electromagnetic actuator unit for moving the valve needle. The lower magnetic ring is positioned on the valve body in such a way that an upper side of the lower magnetic ring is in close contact with an underside of the housing part. The electromagnetic actuator unit abuts the upper magnetic ring and the lower magnetic ring on opposite axial sides. The housing part and/or the lower magnetic ring comprises a cut extending along the axis.

A fuel injector for an internal combustion engine of a motor vehicle. The fuel injector including the following: (a) a pole piece, (b) an armature which can be moved along a movement axis, (c) a coil and (d) a permanent magnet, wherein the movable armature has at least one electrically insulating element which is designed to reduce eddy currents in the armature, and wherein the permanent magnet is fitted such that it generates a magnetic field which produces a force which acts on the armature in the direction of the pole piece. The invention also describes a method for ascertaining a position of a movable armature in a fuel injector and also an engine controller.

The present disclosure provides an electromagnetic actuator that drives an armature by an electromagnetic force. The electromagnetic actuator includes a stator, a coil, and an insulator. The stator is formed of a magnetic material and has a cylindrical portion. The coil is disposed outside of the stator. The coil generates a magnetic field when being energized. The insulator is disposed in a particular region of the stator facing the coil in a radial direction. The insulator extends partially along the stator in a circumferential direction and suppresses a current flowing through the stator in the circumferential direction. The stator is continuously formed entirely along the circumferential direction by the magnetic material.