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.

Fuel injection valve having a magnet armature (18) which interacts with a valve seat (19), which is formed on a valve piece (15), in order to open and close an outflow opening (20), wherein the magnet armature (18) can be moved away from the valve seat (19) by an electromagnet (24). A valve piece (15) delimits a control chamber (12), wherein the outflow opening (20) opens into the control chamber (12), and the control chamber (12) can be charged with fuel at high pressure that exerts a hydraulic force on the valve piece (15). Between the magnet armature (18) and the valve piece (15), there is arranged a bracing element (30) which is preloaded against the valve piece (15) and which exerts a force on the valve piece (15) in the region of the outflow opening (20) in the direction of the control chamber (12).

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.

Fuel injection valve having a magnet armature (18) which interacts with a valve seat (19), which is formed on a valve piece (15), in order to open and close an outflow opening (20), wherein the magnet armature (18) can be moved away from the valve seat (19) by an electromagnet (24). A valve piece (15) delimits a control chamber (12), wherein the outflow opening (20) opens into the control chamber (12), and the control chamber (12) can be charged with fuel at high pressure that exerts a hydraulic force on the valve piece (15). Between the magnet armature (18) and the valve piece (15), there is arranged a bracing element (30) which is preloaded against the valve piece (15) and which exerts a force on the valve piece (15) in the region of the outflow opening (20) in the direction of the control chamber (12).

A solenoid-based fuel injector is described. The fuel injector comprises a tubular body (48) comprising a magnetic material and an armature (16) disposed inside the tubular body. The tubular body has an integrally-formed, inwardly-projecting shelf (52) configured to provide a pole piece.

A solenoid actuator is described. The solenoid actuator comprises an armature, pole piece(s), electromagnet coil(s) arranged, in response to energisation, to cause travel of the armature between first and second positions along a direction of travel, permanent magnet(s) positioned and orientated for latching the armature in at least the first position when the armature is in the first position and spring(s) arranged to bias the armature. The solenoid actuator can be operated to provide partial lift.

A solenoid actuator is described. The solenoid actuator comprises an armature, pole piece(s), electromagnet coil(s) arranged, in response to energization, to cause travel of the armature between first and second positions along a direction of travel, permanent magnet(s) positioned and orientated for latching the armature in at least the first position when the armature is in the first position and spring(s) arranged to bias the armature. The solenoid actuator can be operated to provide partial lift.

A short travel solenoid actuator (44) is disclosed which comprises at least one pole piece (47, 48), an armature (51), an electromagnet coil (46) arranged, in response to energisation, to actuate the armature between first and second positions. A permanent magnet (52) is positioned and orientated so as to latch the armature in the first and second positions when the armature is in the first and second positions respectively. A spring (53) is arranged to bias the armature.