Bistable co-axial electrical actuator - low loss, high force actuation of control rod

摘要

The armature of central rod of the actuator having some suitable mechanical coupling at its exposed end is carried in a co-axial casing, possibly of plastics. The rod itself carries a high coercive force permanent magnet, preferably ferrite and slides in sleeves at the centre of two annular operating coils. The permanent magnet is covered in some resilient plastics to take up impact on operation which is initiated by energising the relevant coil through connections at one end of the unit. The coaxial form minimises radial reaction forces and hence friction. Applications include electrical locks and valves.