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. Teeth portions of the stator each include a base portion that protrudes in a radially inward direction of a yoke portion, a flange portion that is wider than the base portion, and an expanding portion interposed between the base portion and the flange portion. An angle of intersection between the base portion and the expanding portion is 108° to 130°. A distance (thickness) from an inner circumferential side end part to an outer circumferential side end part of the flange portion is 0.2 mm to 2.0 mm.

The invention relates to a rotor unit for a brushless electric motor with an annular rotor core surrounding a central axis, a plurality of magnet arrangements that are arranged around the rotor core in a circumferential direction of the rotor and that each have a convex outer peripheral face, an inner contact face, two axial end faces and two side faces pointing in the circumferential direction, a magnet holder having a number of holding portions which are each arranged between two adjacent magnet arrangements and are moulded onto a ring portion of the magnet holder, wherein the holding portions are configured T-shaped in a cross section along a plane running transversely to the central axis and each have a shank portion and a head portion, wherein the shank portion lies on the side faces of the magnet arrangements in a contact region and the head portion lies on the peripheral faces of the magnet arrangements, wherein the head portion lies on the peripheral faces in a contact area, which contact area is separated by a distance from a transition between the shank portion and the head portion.

The invention relates to a rotor unit for a brushless electric motor with an annular rotor core surrounding a central axis, a plurality of magnet arrangements that are arranged around the rotor core in a circumferential direction of the rotor and that each have a convex outer peripheral face, an inner contact face, two axial end faces and two side faces pointing in the circumferential direction, a magnet holder having a number of holding portions which are each arranged between two adjacent magnet arrangements and are moulded onto a ring portion of the magnet holder, wherein the holding portions are configured T-shaped in a cross section along a plane running transversely to the central axis and each have a shank portion and a head portion, wherein the shank portion lies on the side faces of the magnet arrangements in a contact region and the head portion lies on the peripheral faces of the magnet arrangements, wherein the head portion lies on the peripheral faces in a contact area, which contact area is separated by a distance from a transition between the shank portion and the head portion.

A rotor magnet installation structure includes: a first shaft including a shrinkage-fit portion in which an accommodation space is formed; at least one magnet inserted in the accommodation space, an installation outer diameter of the magnet being greater than an inner diameter of the accommodation space before the magnet is inserted in the accommodation space; and a second shaft comprising a connection portion inserted in the accommodation space, an outer diameter of the connection portion being greater than the inner diameter of the accommodation space before the connection portion is inserted in the accommodation space.

A pump comprises: a housing: a stator disposed inside the housing; a pump gear which is disposed to correspond to the stator and which includes an external gear and an internal gear; and a magnet disposed on the external gear, wherein the magnet includes a first outer circumferential surface, the external gear includes a second outer circumferential surface, and the curvature of the first outer circumferential surface can be smaller than the curvature of the second outer circumferential surface.

A stator for interacting with magnets carried by a rotor of an electric machine, the stator comprising: an active region arranged to be aligned with the magnets carried by the rotor; a first inactive region and a second inactive region, wherein the first and second inactive regions are separated by the active region; and a slotless phase winding comprising a plurality of conductive elements, wherein each conductive element comprises a conductor provided in an insulating housing, and wherein the slotless phase winding is arranged in a serpentine structure comprising: a first active segment in which the conductive elements extend across the active region from the first inactive region to the second inactive region; a second active segment in which the conductive elements extend across the active region from the second inactive region to the first inactive region; and an inactive segment coupling the first active segment to the second active segment, wherein the inactive segment comprises a turn provided in the second inactive region, and wherein at least one of the conductive elements is twisted in the second inactive region.

A rotor for an electric machine is disclosed herein. The rotor comprises: a central shaft; a rotor drum arranged radially outward of the central shaft, wherein the rotor drum comprises a hollow cylinder for carrying permanent magnets on an inner and/or outer surface of the hollow cylinder, and wherein the rotor drum is coaxial with both the central shaft and a rotational axis of the rotor; and a cap arranged to couple the central shaft to the rotor drum to enable the rotor drum and central shaft to rotate together about the rotational axis. An inner portion of the cap is coupled to the central shaft at a first position along the length of the rotational axis, and an outer portion of the cap is coupled to the rotor drum at a second position along the length of the rotational axis. The first position is at a different length along the rotational axis to the second position.

An electric work machine includes magnets appropriately fixed to a rotor core. The electric work machine includes a stator including a stator core, an insulator fixed to the stator core, and a coil attached to the insulator, a rotor rotatable about a rotation axis and including a rotor core, a magnet fixed to the rotor core, and a rotor cup supporting the rotor core and including a core support surface supporting an end face of the rotor core in a first axial direction along the rotation axis and a magnet support surface supporting at least a part of an end face of the magnet in the first axial direction, and an output unit drivable by the rotor.

An electric work machine includes magnets appropriately fixed to a rotor core. The electric work machine includes a stator including a stator core, an insulator fixed to the stator core, and a coil attached to the insulator, a rotor rotatable about a rotation axis and including a rotor core, a magnet fixed to the rotor core, and a rotor cup supporting the rotor core and including a core support surface supporting an end face of the rotor core in a first axial direction along the rotation axis and a magnet support surface supporting at least a part of an end face of the magnet in the first axial direction, and an output unit drivable by the rotor.

Methods, controllers and electric machine systems are described for selective phase control of electric machines (e.g. electric motors and generators).