The invention is a rotational linear motor drive system using a linear stator group arranged in a circular configuration on either side of a non-magnetic conductive rotor. Each stator group with windings are arranged in a circular configuration, and for three phase electrical operation on either side of the rotor. The invention also relates to the frequency driven speed to control the rotor rotation, with synchronized stator drives or out of phase stator drives.
Linear engine drives are well known in the state of the art. An example is a high-speed passenger train or individual transport of single items in manufacturing lines. All use linear motors to move items in translational movement. This common feature can be overcome with a unique configuration on the stator design to allow complete circular movement of a non-magnetic conductive rotor.
For a more complete understanding of this disclosure and features, reference is made to the following description, along with the related drawings, in which:
a illustrate an example rotational linear motor in accordance with this disclosure;
The invention relates to a rotational linear motor drive system as a linear stator group arranged in a circular configuration on either side of a non-magnetic conductive rotor. Having two stator groups, both torque and speed are increased proportional to input voltage. Speed may be increased by advancing the frequency of the input waveform. The magnetic field produced by the stator windings will create an opposite corresponding current and associated magnetic field in the non-magnetic conductive rotor, causing it to spin. The induced current will produce a magnetic field opposing the change in magnetic flux in the stator windings. Three phase electrical input wave form will allow the changing induced current in the non-magnetic conductive rotor to produce the rotational spin of the rotor.
This disclosure provides a configuration for a stator that may be used to drive a rotor attached to a shaft to function as a motor producing rotational movement of the shaft without the use of permanent magnets. As described in more detail below, the non-magnetic conductive rotor will have an induced current such that the induced current always tends to oppose the cause which produced it, hence the associated magnetic field will be in opposition with the stator generated field producing motion of the rotor by repulsive force of like poles.
This disclosure provides a circular configuration of stators windings that produces a rotational linear motor. This embodiment provides for heat removal by use of an integral heat sink on opposite sides of the stator windings. In a first embodiment, the rotor is driven by synchronized stator fields on either side of a non-magnetic conductive rotor. In the second embodiment, the rotor is driven by out of phase stator fields from either side of the rotor. In both embodiments, the speed of the motor is driven by the input frequency of the three phase current. In the third embodiment, the rotor may be driven by a single stator on one side of the rotor. The current embodiment uses three phase current at varying frequency to produce rotational movement of the rotor, but other phasing and waveforms will work as well. No permanent magnets are used in the design of any embodiment.