Electromagnetic actuator, in particular electromagnetic switching or valve device

An electromagnetic actuator, comprising:

• a coil element, which has at least one coil core and a coil arranged circumferentially around the coil core, wherein the coil core has a rotationally symmetrical first region, which has an axis of symmetry and in which the coil core is surrounded circumferentially by the coil;
• a movable magnetic armature body configured as a movable actuator element, which interacts with the coil element to produce a movement, to be activated, of the armature body, and which is supported in the actuator on one side by a bearing device, and can be moved from a first position into a second position by activating the coil element, wherein the bearing device is arranged radially offset relative to the axis of symmetry of the coil core, and the armature body extends from the bearing device radially over the coil core from a first side to a second side of the coil core;
• wherein the coil core has a second region, which extends radially beyond the first region and which is arranged on the second side of the coil core between the coil and the armature body in the direction of axis of symmetry, such that an air gap between the coil core and the armature body in the direction of the axis of symmetry is smaller on the second side of the coil core than on the first side when the armature body is in the first position;
• wherein the armature body has a first region, in which the armature body is supported in the actuator by means of the bearing device, and a second region, which extends over the second region of the coil core, and wherein the armature body has a magnetic resistance per unit of length in the first region which is increased in relation to a magnetic resistance per unit of length in the second region of the armature body.