Abstract: A rotor for a nutating motor has an annular cavity formed in one face thereof, which cavity receives a helically wound ring of magnetically permeable material.A gate valve operator assembly couples the hollow output shaft of a nutating motor to a valve stem, which axially moves within the hollow output shaft. An internally threaded spindle, or stem nut, is rotatably mounted to engage the externally threaded valve stem. The spindle and the hollow motor shaft are coupled together by means of a tab engaging a correspondingly formed notch. Axial movement of the spindle is prevented by means of a flanged radially extending circumferential rim formed as part of the spindle.

Abstract: A constant velocity coupling joint provides rotary motion to an output shaft of a nutating motor or shaft driven by a nutating member. A nutating plate is supported by the coupling and the nutating motion of the plate is transformed to rotary motion of the output shaft. The coupling includes a plurality of balls which are mounted in slots formed between a radially extending coupling plate fixed to the shaft and the nutating rotor member. The balls are held in position by a pair of thrust spacers positioned on each side of the coupling plate. The thrust spacers also provide rolling support for the nutating plate.

Abstract: A current sensing circuit monitors the currents flowing through the stator windings of a nutating motor. The current drive circuits for the windings are capable of delivering large currents with a fast rise time so that the magnetic circuits of the nutating motor quickly saturate, providing precise operation of the motor. Steering diodes quickly discharge the windings into the power supply. When a predetermined winding current level is exceeded, the current sensing circuit produces an output signal which momentarily disables the current drive circuits for the windings so that the stator winding currents are limited to levels sufficient to precisely operate the nutating rotor. The sensing circuit has a hysteresis characteristic which in conjunction with the energy stored in a winding causes the current in a winding to be maintained between certain maximum and minimum levels.