A motor includes a cylindrical rotor core, and a magnet group including first magnets and second magnets alternately arranged along a circumferential direction of the rotor core. A first magnetic flux line generated in the first magnets extends along a radial direction of the rotor core, and a second magnetic flux line generated in the second magnets is inclined with respect to the first magnetic flux line. The rotor core includes an inner portion located on a radially inner side of the magnet group and an outer portion located on a radially outer side of the magnet group. The outer portion includes a first iron core that covers the first magnet from the radially outer side, and a second iron core that covers at least a portion of the second magnet in the central axis direction of the rotor core from the radially outer side.

Electric machine having: a shaft; a rotor with permanent magnets that is fitted to the shaft; a stator having a magnetic core which consists of a series of laminations made of ferromagnetic material and longitudinally crossed by a plurality of stator slots; and a stator winding having a plurality of rigid bars that are inserted in corresponding stator slots and that are covered, on the outside, with an insulating coating. The rotor has a plurality of magnetic elements, which are arranged beside one another around the rotation axis so as to form a closed ring. Each magnetic element is formed by a plurality of permanent magnets which are axially arranged one after the other according to a Halbach array.

The present invention relates to a rotary micromotor (10) designed for actuating an abrasive blade (4) of a surgical or dental tool, the motor comprising a rotor (11) co-operating with a stator (12), and being characterized in that the rotor (11) has a hollow central tubular portion, and comprises an outwardly polarized Halbach array.

A rotor of a rotary electric machine includes a first magnet and a fourth magnet whose magnetic fields are oriented in radial directions of a stator, and a second magnet and a third magnet whose magnetic fields are oriented in circumferential directions of the stator. In the stator, slots are formed between adjacent ones of teeth portions. An electromagnetic coil is provided in the slots. A distal end on an inner circumferential side of the electromagnetic coil is offset from an inner circumferential side end part of a base portion, which is a part of the teeth portion, toward a yoke portion.

A first magnet, a second magnet, a fourth magnet, and a third magnet are retained on a rotor of a rotary electric machine in this order alongside one another in a circumferential direction. Magnetic fields of the first magnet and the fourth magnet are oriented in radial directions of a stator. Magnetic fields of the second magnet and the third magnet are oriented in circumferential directions of the stator. When the rotor is viewed in plan from above or below, a ratio of a total surface area of the first magnet and the fourth magnet to a total surface area of the second magnet and the third magnet is S14:S23=1:0.2 to 1:1.

A dual-rotor machine comprising a dual rotor support structure rotatably connected to a frame. A stationary stator is disposed between the rotors and is fixed to the frame. An inner rotor and outer rotor, each comprising a permanent magnet Halbach array, are coaxially disposed with the stator and are rotable about the stator. In this configuration, the inner rotor channels its magnetic flux to its outside, while the outer rotor channels its magnetic flux to its inside. The magnetic flux density at the stator for the dual-rotor machine can be as high as 2 Tesla or higher for high-grade neodymium-iron-boron permanent magnet material, and the stored magnetic energy for conversion to mechanical or electrical energy available to the stator may be at least 0.5 kJ/m. The rotor Halbach arrays may comprise monolithic permanent magnets with continuously variable magnetic field direction.

The present invention relates to a slotless motor including a thin-walled hollow rotor body 100, and methods of manufacture of such rotors, the methods including hot forming and machining steps. The rotor body has a rotational axis 102 and comprises a first cylindrical portion 104 having a first diameter, a second cylindrical portion 106 having a second diameter, larger than the first diameter and a third cylindrical portion 108 having a third diameter, smaller than the second diameter, the third cylindrical portion located at a second end of the rotor body 100. A first end cap 110 joins the first and second cylindrical portions together, and a second end cap 112 joins the first and second cylindrical portions together. The first, second and third cylindrical portions are all arranged coaxially with the rotational axis 102 of the rotor 100 such that the second cylindrical portion 108 and the first and second end caps collectively define a hollow cavity 114 in the rotor body 100. The rotor body 100 may be provided with a Halbach array.

The present invention relates to a slotless motor including a thin-walled hollow rotor body 100, and methods of manufacture of such rotors, the methods including hot forming and machining steps. The rotor body has a rotational axis 102 and comprises a first cylindrical portion 104 having a first diameter, a second cylindrical portion 106 having a second diameter, larger than the first diameter and a third cylindrical portion 108 having a third diameter, smaller than the second diameter, the third cylindrical portion located at a second end of the rotor body 100. A first end cap 110 joins the first and second cylindrical portions together, and a second end cap 112 joins the first and second cylindrical portions together. The first, second and third cylindrical portions are all arranged coaxially with the rotational axis 102 of the rotor 100 such that the second cylindrical portion 108 and the first and second end caps collectively define a hollow cavity 114 in the rotor body 100. The rotor body 100 may be provided with a Halbach array.

Halbach array electric motor with substantially contiguous electromagnetic cores, comprised of rotors and stators usually configured as permanent magnet and electromagnetic Halbach arrays respectively, wherein the enhanced magnetic forces of said Halbach arrays are focused between said rotors and stators.

Various embodiments provide a system for moving optical elements. The system includes a first rotor and a second rotor configured to rotate in opposite directions. The system further includes a first plurality of paddles coupled to the first rotor, each of the plurality of paddles having an aperture configured to receive a first optical element, and a second plurality of paddles coupled to the second rotor, each of the plurality of paddles having an aperture configured to receive a second optical element. The first rotor and the second rotor are configured to move the first optical element between a retracted position and a desired position and to move the second optical element between the desired position and a retracted position substantially simultaneously such that a reaction torque of the first rotor cancels a reaction torque of the second rotor.