Electromagnetic actuators are provided, which generate bidirectional linear force output without magnetic bias from current or permanent magnets. Systems and methods based on the electromagnetic actuators are also provided. In particular, an electromagnetic actuator having a shaft, an axial bearing, coil assembly, top and bottom stationary flux returns, and top and bottom magnetic flux sensors to measure flux crossing the respective top and bottom axial air gaps.

A bi-stable solenoid includes a housing, a wire coil, a permanent magnet, an armature, a pin, and a spring. The wire coil is arranged within the housing. The armature is slidably arranged within the housing and is moveable between a first armature position and a second armature position. The pin at least partially extends out of the housing and is slidably engaged by the armature. The spring is biased between the armature and the pin. When the pin encounters an intermediate position between a retracted position and an extended position due to the pin engaging an obstruction, the spring is configured to maintain a biasing force on the pin until the obstruction is removed.

An electromagnetic actuator comprises a dual stage action, wherein the actuator comprises an electromagnetic element between two ferromagnetic elements. An electric current driven through the electromagnetic element causes a magnetic field of the electromagnetic element to interact with the magnetic fields of the two ferromagnetic elements.

A latch device (12) for a hydraulic valve (10) is proposed. The latch device (12) comprises a housing (22) and a latch shaft (26), which is supported such that it can move in the housing (22). In order to create a latch device (12), independent of the hydraulic provisioning, the provision of at least one magnetizable ring beam arrangement (38), which is supported on the latch shaft (26), and an electric solenoid arrangement (40), located on the housing (22) around the ring beam arrangement (38) is also proposed, wherein by the supply of current to the solenoid arrangement (40), a positioning force can be produced on the ring beam arrangement (38). Furthermore, a hydraulic valve (10) with the corresponding latch device (12) and a hydraulic arrangement (92) for such a valve (10) are also proposed.

The electromagnetic device includes a coil bobbin around which a coil is wound and that is formed from a non-magnetic material, and a movable core that is provided in a cylindrical hollow portion of the coil bobbin and moves by excitation of the coil. A first protrusion and a second protrusion facing a part of the lower half of the movable core are formed on the inner peripheral surface of the cylindrical hollow portion in ranges extending from two openings to a middle point of the coil bobbin, respectively, and the movable core is supported by the first protrusion and the second protrusion when the movable core moves.

Variable pressure feedback using solenoid-based actuators. Actuators positioned proximate the surface a user's body can include a deflectable armature and a coiled wire to deflect the armature to apply pressure to the user's body surface. A method can control such actuators to apply a respective level of pressure to the user's body surface. Additionally or alternatively, actuators positioned proximate the user's body surface can include solenoid(s) configured for activation, by at least one electrical signal, to generate, for each solenoid, a respective magnetic field and apply a corresponding pressure to the user's body surface. Activation of a solenoid can repel magnetic material to provide the pressure against the user's body surface, or cause the solenoid (or solenoid core thereof) to repel away from magnetic material and toward the user's body surface to apply pressure thereto.

A bistable solenoid valve device for a fluid system is provided. The bistable solenoid valve device comprises a bistable solenoid valve. The bistable solenoid valve comprises a permanent magnet. The bistable solenoid valve further comprises an armature displaceable between a first armature position and a second armature position. The bistable solenoid valve further comprises a first switching coil for energization for a displacement of the armature into the first armature position. The bistable solenoid valve further comprises a second switching coil for energization for a displacement of the armature into the second armature position. The bistable solenoid valve further comprises an evaluation device adapted to measure an induced coil voltage, an induced coil current, or both the induced coil voltage and the induced coil current, at one or more of the non-energized switching coils. The evaluation device is further adapted to assess a switching behavior of the armature.

A solenoid valve includes a body having a flow channel, and a solenoid part coupled to the body. The solenoid part includes a core housing. A movable core can be accommodated inside the core housing. A flange part of the core housing is expanded radially outwardly from a guide part which guides the movable core. Further, a thick portion is provided at a boundary portion between the flange part and the guide part on a core part side. The thick portion becomes gradually thick toward the guide part.

An electromagnetic actuator includes a housing and a bobbin positioned within the housing and secured relative thereto so as to be centered therein, the bobbin comprising a bobbin formed of a non-magnetic material. The electromagnetic actuator also includes a coil wound about the bobbin and a magnetic circuit comprising a plurality of actuator components positioned within the housing and on or adjacent to the bobbin. The actuator components include a permanent magnet that induces a magnetic flux flow through the magnetic circuit so as to generate a magnetic force, and an armature selectively movable within an opening formed through the bobbin responsive to the magnetic force and to current selectively provided to the coil. The bobbin locates and centers the components of the magnetic circuit about the central axis and provides a bearing surface for the armature as it moves within the opening formed through the bobbin.

A linear actuator may include a movable element including a cylindrical permanent magnet; a stationary element including a coil bobbin that surrounds the permanent magnet at an outside in a radial direction; a spring member connected to the movable element and the coil bobbin, and supporting the movable element to be movable in an axial direction in relation to the coil bobbin; a coil wound around the coil bobbin, for configuring a magnetic drive mechanism together with the permanent magnet, the magnetic drive mechanism being structured to drive the movable element in the axial direction; and a gel damper member being sandwiched between the stationary element and the movable element in the axial direction.