field, sub-assemblies (12, 14 ) and the coil assembly (16) having a linear coil actuators are is disclosed , wherein the field sub-assemblies each of which includes a field blank , the field sub - assembly and at least one of the group also includes a magnet . Each magnet has the same or a different group sizes , a spring with a certain load characteristics such as a spring with a constant K, and a magnet arranged to provide a magnetic flux density distribution and the magnetic polarity at the air gap . The field sub - assembly with respect to each other , are positioned to form a gap between the field and the other field assembly including a magnet assembly , the coil assembly is movable in a gap
展开▼
