An electric motor includes a stator, and a rotor having a plurality of magnetic poles. Each magnetic pole includes a rotor core having through holes arranged circumferentially side by side, and a permanent magnet inserted into each through hole. A length of a portion of the rotor core in a radial direction of the rotor is shorter than a length of the permanent magnet in the radial direction of the rotor. The length of the portion of the rotor core is measured between an inner surface of each of the through holes adjacent to an outer periphery of the rotor and an outer peripheral surface of the rotor. The permanent magnets generate a magnetic flux in a magnetic circuit showing a smaller magnetic resistance in a portion of the rotor radially outward of the permanent magnets than in a portion of the rotor radially inward of the permanent magnets.

An oil field pump installed within a pipe that connects to an oil field, feeds accumulated extraction oil in a predetermined direction and includes a rotor, a stator mounted on the outer circumference of the rotor, a flow path for flow of the extraction oil connecting an area formed within the rotor to an area formed between the rotor and the stator, a thrust bearing that supports the axial weight of the rotor and the stator, and a supply pipe that supplies a portion of the extraction oil in the flow path to the thrust bearing. The thrust bearing includes a protrusion part fixed to the outer circumference of the rotor and rotating as one piece with the rotor, and a facing part fixed to the stator and facing opposite a surface in the axial direction of the protrusion.

A flywheel system includes a fixture including a bottom support, a rotor characterized by a gravitational load and configured to rotate above the bottom support about a rotation axis, and a bottom magnetic levitation bearing. The bottom magnetic levitation bearing includes (a) a ring of first magnets mechanically coupled with a bottom end of the rotor, (b) a ring of second magnets mechanically coupled to the bottom support, beneath the ring of first magnets, the second magnets repelling the first magnets to magnetically support at least a portion of the gravitational load above the bottom support, (c) a ring of third magnets mechanically coupled with the bottom end, and (d) a ring of fourth magnets mechanically coupled to the bottom support radially outwards from the ring of third magnets, the fourth magnets repelling the third magnets to at least reduce radial decentering of the rotor relative to the fixture.

An electric motor including a tension member is proposed. The electric motor includes the tension member installed therein and composed of step parts stacked in multiple steps, so that structural strength and structural robustness are improved.

An outer rotor direct drive motor with a position encoder includes an outer rotor and a stator disposed in the outer rotor, wherein the stator includes: a stator chassis; a stator printed circuit board disposed on an side of the stator chassis, at least an excitation coil and a receiving coil being printed at the stator printed circuit board; and a stator winding disposed on the stator printed circuit board; wherein the outer rotor changes a coupling strength between the excitation coil and the receiving coil. The present invention has the following advantages: the installation method is flexible, and supports through-shaft installation without occupying too much space of the motor body; the sensor structure is stable, the rotor scale area and the induction coil are all printed on the printed circuit board, even in the case where the rotational speed is too fast, deformation or cracking will not be occurred.

A motor is provided. The motor includes a motor body and a rotor assembly. The rotor assembly includes a magnetic core mounted to a rotor shaft. The rotor assembly may include standoffs for accurately axially locating the magnetic core relative to rotor bearings. A drive nut adjustment arrangement may be provided. A mechanical interconnection between the drive nut and rotor shaft may be provided. A trailing end lead screw support may be provided. An axial preload arrangement may be provided to axially locate the rotor assembly within the motor body.

Systems and methods for increasing hydrocarbon production using an electrical submersible pump are described. The methods typically include, for example, configuring an electrical submersible pump comprising a gas separator to induce a gas lift effect in a well comprising a tubing within a casing. Hydrocarbon production from the well is therefore increased using the electrical submersible pump.

An electrical machine includes a stator with a stator body supporting an electrical stator and a rotor. The rotor is supported by a bearing having a radial bearing section forming a radial gas bearing and an axial bearing section forming an axial gas bearing, the stator side parts of these bearing sections being a stator side radial bearing part and a stator side axial bearing part that are rigidly connected to one another and together form a stator bearing structure. The stator bearing structure is mounted to the other parts of the stator by either the stator side radial or axial bearing part being rigidly mounted to these other parts, and the other bearing part are connected to these other parts by an elastic support or not at all.

A linear actuator 1 includes a motor 2, a rotary unit (a screw shaft 5) to be rotationally driven by the motor 2, and a linear motion unit 6 to be screwed with the screw shaft 5 and to linearly move in an axial direction in accordance with rotation of the screw shaft 5. The linear motion unit 6 includes a linear motion unit main body 7 (a nut 10 and a spring case 11), an output member 8 provided to be relatively movable in the axial direction with respect to the linear motion unit main body 7, and configured to abut an operation target P, and a spring 9 disposed between the linear motion unit main body 7 and the output member 8 in the axial direction.

Methods, systems, and devices are disclosed for wind power generation. In one aspect, a wind power generator includes a support base; inductors positioned over the support base in a circular array; an annulus ring track fixed to the base support and providing a circular track around which the inductors are located; an annulus ring rotor placed on the annulus ring track and engaged to rollers in the circular track so that the annulus ring rotor can rotate relative to the an annulus ring track, in which the annulus ring rotor include separate magnets to move through the circular array of inductors to cause generation of electric currents; and a wind rotor assembly coupled to the annulus ring rotor and including wind-deflecting blades that rotate with the rotor and a hollow central interior for containing a wind vortex formed from deflecting wind by the blades to convert into the electric energy.