Abstract: The apparatus employs magnetoresistive sensors (28) to generate a sinusoid having a time-varying instantaneous frequency commensurate with the instantaneous frequency of the angular displacement of a motor's rotating shaft (40). The resultant signal is then fed to a mixture of fixed-phase-shifting circuits (22) whose outputs are then amplified by voltage-controlled amplifiers and fed to independently wired stator phases (56).

Abstract: This invention employs a generic axial modulating mechanism to manipulate the pitch of the blades of a fan or propeller; conceptually, this is a threaded bolt and nut where the threaded bolt would be analogous to a rotating shaft, with an acme thread (i.e. the “rotor thread”) on its exterior, and the nut would be analogous to the axial modulator of this teaching. The “nut,” or axial modulator, is further spun above and beyond the rotation in the rotating bolt or rotating shaft. The axial motion of the axial modulator is then deployed to do useful work i.e. manipulate the pitch of the blades of a fan or propeller. This invention is a continuation in part of a previous variant disclosed where the means of modulating the axial modulator was magnetic. The variation introduced in this teaching instead achieves the modulation using a gear-driven arrangement.

Abstract: The apparatus employs magnetoresistive sensors (28) to generate a sinusoid having a time-varying instantaneous frequency commensurate with the instantaneous frequency of the angular displacement of a motor's rotating shaft (40). The resultant signal is then fed to a mixture of fixed-phase-shifting circuits (22) whose outputs are then amplified by voltage-controlled amplifiers and fed to independently wired stator phases (56).

Abstract: The invention describes a mechanism to cause an actuator born on a rotating shaft to modulate backwards and forwards independently of the motion of the rotating shaft. This mechanism is then used to realize a controllable-pitch blade fan. The axial modulating mechanism is achieved by mounting a thread on the rotating shaft onto which an axial modulator with a cylindrical cavity having a mating thread is mounted; magnets induce the axial modulator to rotate independently of the shaft's rotation in turn causing the axial modulator to move linearly along the shaft. This mechanism's linearly motion is then used to force blades rotatably mounted on the shaft to rotate.