In a main magnetic circuit, first pulling force generated based on a first component of the magnetic flux flowing through the main magnetic path pulls a movable core in a reciprocation direction of the movable core. The first pulling force increases with a reduction of a dimension of the gap. In an auxiliary magnetic circuit, second pulling force generated based on the second component of the magnetic flux flowing through the auxiliary magnetic path pulls the movable core in the reciprocation direction of the movable core. In the auxiliary magnetic circuit, the second pulling force with the dimension of the gap being within a first range is changed to be higher than the second pulling force with the dimension of the gap being within a second range, the second range being smaller than the first range.

A haptic electromagnetic actuator for track pad is provided. The actuator includes an array of electromagnets with alternating South and North poles on a first end, each magnet comprising a metal core and an electrical wire around the metal core. The array of magnets is coupled to a base plate on a second end opposite to the first end. The actuator also includes an attraction plate at a distance from the first end of the array of the magnets such that the attraction plate moves toward the magnets when an electrical current flows through the electrical wire around the metal core and moves away from the magnets when the current becomes zero. The array of magnets is configured to form a uniform gap from the attraction plate.

In a main magnetic circuit, first pulling force generated based on a first component of the magnetic flux flowing through the main magnetic path pulls a movable core in a reciprocation direction of the movable core. The first pulling force increases with a reduction of a dimension of the gap. In an auxiliary magnetic circuit, second pulling force generated based on the second component of the magnetic flux flowing through the auxiliary magnetic path pulls the movable core in the reciprocation direction of the movable core. In the auxiliary magnetic circuit, the second pulling force with the dimension of the gap being within a first range is changed to be higher than the second pulling force with the dimension of the gap being within a second range, the second range being smaller than the first range.

An alignment member for a solenoid is provided. The solenoid includes a housing, a solenoid coil arranged within the housing, a first pole piece arranged within the housing, a second pole piece arranged at least partially within the housing, and a disk. The alignment member includes a first end, a second end opposite the first end, and a center portion that defines a center portion diameter that is less than a diameter defined by the first end and the second end.

In an electromagnetic actuator having a housing, two ferromagnetic pole shoes are distanced from each other and are rigidly connected to the housing. A mobile structure, which can be moved in the housing along an axis between two end positions, is arranged between the pole shoes, includes at least one magnet system, and is connected to a shaft that is axially displaceable in the housing. The magnet system includes at least one arrangement of at least one permanent magnet polarized radially with respect to the axis, and an annular coil connectable to a current source. The magnet system forms, together with the pole shoes, an air gap system having axially variable air gaps. The mobile structure is securable in each end position without excitation of the coil and is movable from one assumed end position into the opposite end position by excitation of the coil.

An electromechanical solenoid has a solenoid assembly including a solenoid coil with a coil aperture formed therein. A pole piece assembly is positioned at least partially within the coil aperture, the pole piece assembly including a first pole piece and a second pole piece positioned at least partially within an hour-glass shaped alignment member. The first pole piece has a first bore and a first outer tapered surface extending away from the first bore, and the second pole piece has a second bore and a second outer tapered surface extending away from the second bore. An armature is moveable within the first bore and the second bore in response to a magnetic field produced by the solenoid coil.