A rotor includes a rotor core having magnet insertion holes in a number corresponding to a pole number, and a center hole. The rotor core has first slits and ribs alternately arranged in the circumferential direction along a periphery of the center hole, and second slits on an outer side with respect to the first slits in the radial direction. The first slits and the second slits are both equal in number to half or an integer multiple of the pole number. Each second slit is formed to cover the rib from an outer side in the radial direction. Each first slit has a length A1 in the circumferential direction and a width A2 in the radial direction. Each second slit has a length B1 in the circumferential direction and a width B2 in the radial direction. A1>A2, B1>B2, and A1>B1 are satisfied.

A rotor includes a rotor core having magnet insertion holes in a number corresponding to a pole number, and a center hole. The rotor core has first slits and ribs alternately arranged in the circumferential direction along a periphery of the center hole, and second slits on an outer side with respect to the first slits in the radial direction. The first slits and the second slits are both equal in number to half or an integer multiple of the pole number. Each second slit is formed to cover the rib from an outer side in the radial direction. Each first slit has a length A1 in the circumferential direction and a width A2 in the radial direction. Each second slit has a length B1 in the circumferential direction and a width B2 in the radial direction. A1>A2, B1>B2, and A1>B1 are satisfied.

The disclosure relates to the design of a stator tooth for a stator of an electric machine, in particular, for an electric drive system of an aircraft. The stator tooth is formed from a multiplicity of sheet metal layers which are stacked on one another in an axial direction. At least those sheet metal layers which delimit the stator tooth in the axial direction have slits which extend in the radial direction and which have the effect of suppressing eddy currents generated in the sheet metal layers, for example, by stray fields, during the operation of the electric machine.

An electric machine includes a stator formed from a plurality of stacked laminations and defining a center bore and a rotor disposed within the center bore. The rotor is configured to output a rotational torque in response to an input current delivered to the stator. At least one of the stacked laminations of the stator includes a pattern of perforations disposed at a yoke portion of the stator to attenuate structure-bore transmission of vibration during operation of the electric machine.

A salient-pole rotor includes a magnetic pole portion having a plurality of protruding portions which protrude outward in a radial direction from a base portion, is disposed to be spaced apart from each other at intervals in a circumferential direction of a rotary shaft and have outer circumferential surfaces along an imaginary cylindrical surface. The magnetic pole portion includes a concave portion reinforcing portion which is provided inside the concave portion and a cylindrical reinforcing portion which covers the magnetic pole portion and the outer circumferential surface of the concave portion reinforcing portion. The base portion has a plurality of slits extending in the circumferential direction to be spaced apart from each other in the radial direction. A slit reinforcing portion formed of a non-magnetic material is provided inside the slits.

A rotor for an electric machine having posts extending partially or completely between end irons. Each end iron is formed of a single piece of magnetic material with the posts extending from it, including the other end iron where the posts extend completely between them. Magnets are arranged between the posts with poles facing the posts to concentrate flux. In order to prevent too much of the flux from being drawn into flux paths through the end irons, the total magnetic flux is made to exceed a saturation flux of at least a portion of the flux path. This may be achieved by using interdigitated posts extending only partially between the end irons to provide gaps in the flux path, by providing flux resistors in the end irons to reduce a saturation flux below the total flux, or by using high aspect ratio magnets or posts so that the magnetic flux exceeds a saturation flux of the posts or end irons.

An electric motor is disclosed having a detachable stator tooth. In some implementations, coil windings of the electric motor may be coupled to one or more drivers independently of other coil windings. A method of repairing and manufacturing an electric motor having a detachable stator tooth is also disclosed.

An electric motor is disclosed having a detachable stator tooth. In some implementations, coil windings of the electric motor may be coupled to one or more drivers independently of other coil windings. A method of repairing and manufacturing an electric motor having a detachable stator tooth is also disclosed.

An electric motor has a first carrier having an array of electromagnetic elements and a second carrier having electromagnetic elements defining magnetic poles. The first and second carriers each define an axis. An airgap is formed between the first and second carriers when in an operational position. An inner thrust bearing connects the first and second carriers and is arranged to allow relative rotary motion of the carriers. An outer thrust bearing connects the first and second carriers and is arranged to allow relative rotary motion of the carriers. The electromagnetic elements of each of the first and second carriers are arranged radially inward of the outer thrust bearing and radially outward of the inner thrust bearing. The inner thrust bearing and the outer thrust bearing are arranged to maintain the airgap against a magnetic attraction of the electromagnetic elements of the first and second carriers.

An electric motor has a first carrier having an array of electromagnetic elements and a second carrier having electromagnetic elements defining magnetic poles. The first and second carriers each define an axis. An airgap is formed between the first and second carriers when in an operational position. An inner thrust bearing connects the first and second carriers and is arranged to allow relative rotary motion of the carriers. An outer thrust bearing connects the first and second carriers and is arranged to allow relative rotary motion of the carriers. The electromagnetic elements of each of the first and second carriers are arranged radially inward of the outer thrust bearing and radially outward of the inner thrust bearing. The inner thrust bearing and the outer thrust bearing are arranged to maintain the airgap against a magnetic attraction of the electromagnetic elements of the first and second carriers.