Plane sheets which have the same shape as the magnetic circuit and are relatively movable along their contact surface are arranged in a stack. The stack is grasped and part of the circuit is bent out of alignment with the plane of the sheets to enable a coil to be placed on a portion of the circuit which...http://www.google.com/patents/US5457873?utm_source=gb-gplus-sharePatent US5457873 - Method for mounting an electrical coil on a magnetic circuit with an air gap
