An electromagnetic actuator. The electromagnetic armature includes: an armature movable in an axial direction in an armature space; a magnetic coil for generating a magnetic field to move the armature; an operating element motion-coupled to the armature; and a flux-directing part, disposed at an axial end of the magnetic coil, having a recess which extends in the axial direction and in which the operating element is displaceably disposed, the flux-directing part being embodied in two parts. The flux-directing part is embodiment in two parts from a base part facing toward the armature and a top part facing away from the armature. The operating element is mounted, displaceably in the axial direction, in a first bearing point embodied on the top part and in a second bearing point embodied on the base part.

Embodiments of the present disclosure include a method and apparatus. An exemplary apparatus includes a solenoid assembly that includes a ferromagnetic core tube having a first channel and a second channel disposed on the radial exterior surface of the ferromagnetic core tube. The first channel and the second channel circumscribe the ferromagnetic core tube along a given portion of the longitudinal axis. The first channel and the second channel are spaced from one another along the longitudinal axis. The first channel has a first magnetic ring radially spaced apart from a first thin wall. The second channel has a second magnetic ring radially spaced part from a second thin wall. The solenoid assembly also includes a coil located radially outward of the ferromagnetic core tube.

An electromagnetic actuator includes an essentially cylindrical pole tube, an armature situated radially within the pole tube, and an electromagnetic coil situated radially outside of the pole tube, the pole tube including a first axial end area, a second axial end area, and an outer recess, which extends in the circumferential direction, in proximity to the first axial end area on an outer side of the pole tube. On an inner side, the pole tube includes an inner recess that extends in the circumferential direction and whose axial extension is smaller than an axial extension of the outer recess and that is situated approximately at the height of an edge area of the outer recess pointing away from the second axial end area viewed in the axial direction.

A valve portion has a sleeve and a valve body inserted into the sleeve. A solenoid portion includes a stator core having a magnetic attraction core, a sliding core, a magnetic flux passage suppressing portion, a yoke having a bottom portion, a side surface portion, and a thin wall portion, a coil portion, a plunger, and a magnetic tubular base portion. The base portion has a first tubular portion in which a first outer peripheral surface of the sleeve is press-fitted into inside and fastened to the first outer peripheral surface, a flange portion that has an outer diameter larger than the outer diameter of the first tubular portion, is arranged on an outer side in a radial direction of a second outer peripheral surface of the magnetic attraction core, and is caulked and fixed to the thin wall portion while being in contact with the yoke inside the yoke.

A solenoid valve includes a valve portion and a solenoid portion. The valve portion has a sleeve and a valve body inserted into the sleeve. The solenoid portion includes a stator core having a magnetic attraction core, a sliding core, a magnetic flux passage suppressing portion that suppresses the passage of magnetic flux between the sliding core and the magnetic attraction core, a magnetic yoke, a coil portion, a plunger, and a magnetic tubular base portion. The base portion is fastened to a first outer peripheral surface of an end on the solenoid portion side in the axial direction of the sleeve, is arranged outside a radial direction of a second outer peripheral surface of the end on the valve portion side in the axial direction of the magnetic attraction core, and comes into contact with the yoke inside the yoke.

A solenoid includes a coil portion and a yoke having a side surface portion along an axial direction so as to accommodate the coil portion. A gap in a radial direction that communicates a radial outside of a first magnetic flux transfer portion with an outside of the solenoid is formed between an inner surface of the side surface portion and an outer surface of the coil portion, and a protrusion is formed on at least one of an inner surface and an outer surface and protrudes in the radial direction to reduce a size of at least a part of the gap.

A solenoid includes a coil portion, a yoke having a side portion and a bottom portion, a plunger, and a stator core. The stator core has a magnetic attraction core and a sliding core which has a tubular core portion and a first magnetic flux transfer portion formed from the tubular core portion and the core end portion toward an outside in a radial direction to transfer magnetic flux between the yoke and the core portion. A breathing groove communicating an inside and an outside of the first magnetic flux transfer portion in the radial direction is formed on at least one of a first facing surface facing the bottom portion in a first magnetic flux transfer portion and a second facing surface facing the first magnetic flux transfer portion at the bottom portion so as to be positioned in a vertical direction when the solenoid is assembled.

A solenoid includes a coil, a cylindrical sliding core, a columnar plunger, a bottomed cylindrical yoke including a cylindrical portion and a bottom portion that is connected to the cylindrical portion and faces a base end surface of the plunger, and the bottomed cylindrical yoke configured to accommodate the coil, the sliding core, and the plunger, a magnetic attraction core arranged to face a distal end surface of the plunger, and a magnetic flux transfer member that transfers magnetic flux between the sliding core and the yoke. When the plunger is closest to the magnetic attraction core, a position of the base end surface of the plunger along an axial direction is the same as position of the end of the sliding core along the axial direction, or is closer to the bottom portion side of the sliding core along the axial direction than the end of the sliding core.

An electromagnetic actuator includes: a stator; and a movable element attracted from a stroke start position to a stroke end position in a predetermined stroke in an axial direction by magnetic force generated between the stator and the movable element when a coil is energized. The stator includes a first stator located adjacent to the movable element at the stroke start position and a second stator located closer to the movable element at the stroke end position than at the stroke start position. The movable element includes a tapered portion so as to reduce a gap between the first stator and the movable element as the movable element is moved toward the stroke end position. The first stator includes a curved surface that has a convex shape so as to expand a gap between an opening end of the first stator facing the second stator and the movable element.

Presented are a single coil apparatus and a method of forming. An exemplary apparatus includes solenoid assembly. The solenoid assembly includes a core tube extending along a longitudinal axis. The solenoid assembly further includes a first magnet and a second magnet located outside the core tube, the first magnet spaced along the longitudinal axis from the second magnet, and an excitation coil disposed radially outward of the first magnet and the second magnet.