Electric stepping motors and remote registers

An electric stepping motor comprising a permanently magnetised rotor having peripheral magnetic poles, means mounting said rotor for rotation about an axis of rotation, a stationary magnetic circuit comprising a pair of stator pole members each having at least one polar surface positioned adjacent to the periphery of the rotor, an electromagnet winding associated with a part of the magnetic circuit to produce, when energised, opposite magnetic polarities in the respective stator pole members, and stationary magnetic biasing means fixedly mounted on frame means adjacent to said rotor, the magnetic flux in the magnetic circuit and through the rotor by way of the polar surfaces being sufficient as to produce and output rotary movement of said rotor through a first predetermined angle in a given direction in response to an input energizing current to said winding, and the magnetic flux due to said biasing means being sufficient as to produce a rotary movement of the rotor through a second predetermined angle in the same direction as the first-mentioned direction in response to de-energisation of said winding but being insufficient to prevent the rotation of the rotor through said first predetermined angle when said winding is energized.