The invention concerns a brushless torque motor with an angular displacement less than 180.degree. and an application of this motor to controlling the angular displacement of a shaft, for example a shaft carrying a scanning mirror (or an antenna support, a filter, a lens, etc.), preferably but not exclusively in space applications.
Many kinds of torque motors are already known. The operation of these motors is based on producing a torque by causing an appropriate electric current to flow in wires, in practice portions of coils, disposed in a permanent magnetic field. However, known torque motors usually have a large overall dimension transversely or parallel to the rotation axis and a rotor (i.e., the rotating part of the motor) with a high inertia, especially if the latter carries the members generating the permanent magnetic field (in practice permanent magnets).
The term "armature" refers to the part of the motor carrying the wires carrying the current and the term "field assembly" refers to the complementary part of the motor carrying the members generating the permanent magnetic field.