An electromagnetic actuator comprising a moving armature (41) comprising a pin (43) and a permanent magnet arrangement (45) arranged coaxially with the pin (43) and secured to it, and an excitation coil arrangement (42) arranged coaxially with the pin (43). The coil arrangement (42) is suppliable with a current to cause a movement of the movable armature (41). The actuator further comprises a surface (51) of ferromagnetic material. The permanent magnet arrangement (45) is axially interposed between the surface (51) of ferromagnetic material and the excitation coil arrangement (42). The permanent magnet arrangement (45) comprises a plurality of permanent magnet regions (45a) arranged around the pin (43) of the moving armature (41), wherein each permanent magnet region (45a) has a polarity opposite to the polarities of the permanent magnet regions (45a) angularly adjacent thereto. The excitation coil arrangement (42) comprises a coil having a lobed shape.

An electromagnetic actuator comprising a moving armature (41) comprising a pin (43) and a permanent magnet arrangement (45) arranged coaxially with the pin (43) and secured to it, and an excitation coil arrangement (42) arranged coaxially with the pin (43). The coil arrangement (42) is suppliable with a current to cause a movement of the movable armature (41). The actuator further comprises a surface (51) of ferromagnetic material. The permanent magnet arrangement (45) is axially interposed between the surface (51) of ferromagnetic material and the excitation coil arrangement (42). The permanent magnet arrangement (45) comprises a plurality of permanent magnet regions (45a) arranged around the pin (43) of the moving armature (41), wherein each permanent magnet region (45a) has a polarity opposite to the polarities of the permanent magnet regions (45a) angularly adjacent thereto. The excitation coil arrangement (42) comprises a coil having a lobed shape.

A rotary solenoid includes: a fixed body portion having a casing in which a pair of bearing portions and positioned on front and rear sides are provided; and a movable body portion having a rotation shaft rotatably supported by the pair of bearing portions. The fixed body portion includes: the casing formed of a magnetic material; and an air-cored coil of which the surface orthogonal to an axial direction of the rotation shaft is fixed to an inner surface of the casing. The movable body portion includes: a rotor yoke having one end fixed to the rotation shaft; and a magnet portion having a pair of magnets and fixed to an opposing surface positioned on the other end side of the rotor yoke serving as a surface opposing the air-cored coil and disposed along a rotation direction of the opposing surface.

A servo valve has a movable element disposed inside a body, and a drive unit to slide the movable element in the axial direction. A first elastic portion on one end portion side of the body has a first elastic force to press the movable element toward the drive unit connected to another end portion of the body; a second elastic portion on another end portion side of the body has a second elastic force to press the movable element toward the one end portion side of the body. A connecting portion is connected to the second elastic portion, wherein at a neutral position of the movable element, the connecting portion abuts against an inner peripheral surface of the body and against the movable element. An end of one of the first and second elastic portions is fixed directly to the movable element, and an end of the other of the first and second elastic portions is connected to the connecting portion.

An actuator has a first stator with four first poles, a second stator with four second poles aligned with the four first poles, a permanent magnet between the first stator and the second stator, four armatures positioned at terminal ends of the aligned four first poles and four second poles, and coils wrapped around the first stator and the second stator. A controller selectively applies current to the coils to migrate flux created by the permanent magnet through selective poles of the first stator and the second stator to selectively alter air gap sizes associated with the four armatures.

An actuator has a first stator with four first poles, a second stator with four second poles aligned with the four first poles, a permanent magnet between the first stator and the second stator, four armatures positioned at terminal ends of the aligned four first poles and four second poles, and coils wrapped around the first stator and the second stator. A controller selectively applies current to the coils to migrate flux created by the permanent magnet through selective poles of the first stator and the second stator to selectively alter air gap sizes associated with the four armatures.

An electromagnetic linear actuator is provided having a housing having a casing section and an end piece, a coil arrangement having two coils which extend about a common axis, are wound in opposite directions and are offset axially from one another, an armature arrangement mounted displacably in the housing along the axis, and a shaft, which passes through the end piece. A magnet arrangement at the end of the shaft has an axially magnetized permanent magnet and two disc-shaped flux conducting pieces are arranged on a front side. The first coil which faces away from the free end of the shaft has a region with a reduced internal diameter. A core of a magnetically active material is held in the coil. In each end positions of the armature arrangement, at least 50% of the axial length of the magnet arrangement is overlapped by one of the coils.

An electromagnetic linear actuator is provided having a housing having a casing section and an end piece, a coil arrangement having two coils which extend about a common axis, are wound in opposite directions and are offset axially from one another, an armature arrangement mounted displacably in the housing along the axis, and a shaft, which passes through the end piece. A magnet arrangement at the end of the shaft has an axially magnetized permanent magnet and two disc-shaped flux conducting pieces are arranged on a front side. The first coil which faces away from the free end of the shaft has a region with a reduced internal diameter. A core of a magnetically active material is held in the coil. In each end positions of the armature arrangement, at least 50% of the axial length of the magnet arrangement is overlapped by one of the coils.

An actuating mechanism includes a main body, an electromagnetic device fixed to the main body, and a swinging rod swingably connected to the main body. A position of connection between the swinging rod and the main body is opposite to an iron core of the electromagnetic device, and an upper end of the swinging rod is opposite to and spaced apart from the electromagnetic device. A permanent magnet is disposed on the upper end of the swinging rod, and a magnetic pole direction of the permanent magnet and a magnetic pole direction of the electromagnetic device cross each other. Since the permanent magnet on the swinging rod is opposite to and spaced apart from the electromagnetic device, the swinging rod is not in contact with the electromagnetic device during working process. This avoids knocking of the swinging rod on other components, and therefore prevents noise, reduces wear.

An impact actuator with 2-degree of freedom, which may generate an impact stimulation in any direction on the plane, includes a body having a magnetic substance that is movable therein, one upper solenoid attached to an upper portion of the body, and three or more lower solenoids attached to a lower portion of the body, wherein the upper solenoid and the three or more lower solenoids are independently supplied with AC power from a power supply, respectively.