A rotor unit for a brushless electric motor, incudes 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. 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. 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.

A rotor unit for a brushless electric motor, incudes 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. 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. 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.

An actuator is driven by a brushless motor having a rotor with axially extended magnets, permitting axial movement of the rotor while maintaining overlap between the magnets and a stator secured in a fixed position. The rotor is engaged with a fixed structure by a connection such as a ramp or thread that translates rotation into axial movement of the rotor along a rotational axis of the actuator. A valve member coupled to the rotor moves axially between a closed position and a range of positions that regulate fluid flow through a valve. A motor control circuit applies power to the stator coils to rotate the rotor and coupled valve member to a desired axial position and maintain the rotor and valve member at the selected position. The rotor and valve member may be biased toward a rotational position corresponding to a closed position of the valve member.

A rotor structure includes a rotor body and a plurality of magnets. The rotor body has a plurality of surrounding magnet-setting areas, and each magnet setting area has a first magnet slot and a second magnet slot symmetrically arranged to a centripetal axis. A first outer end of the first magnet slot and a second outer end of the second magnet slot are close to the centripetal axis and rotor's outer edge. A first outer end of the first magnet slot and a second outer end of the second magnet slot are distant to the centripetal axis and rotor's outer edge. The outer edge has a plurality of notches intersected by the corresponding centripetal axes. The magnets are respectively fixed to the first magnet slots and the second magnet slots of the magnet-setting areas.

A rotor that is downsized while achieving high output of the electric motor is provided. The rotor includes a plurality of main magnets and a plurality of auxiliary magnets. The auxiliary magnets are fit into a plurality of respective grooves formed along a rotation shaft direction in an outer periphery of a rotation shaft arranged at the center of the rotor, are projected from the outer periphery of the rotation shaft to an outer side of a radial direction, and have a magnetization direction along a circumferential direction of the rotor. Magnetic field directions of the auxiliary magnets that are adjacent to each other are opposite to each other in the circumferential direction. The main magnets are arranged in projected parts of the auxiliary magnets that are adjacent to each other and have a magnetization direction that is along the radial direction of the rotor.

Provided are a winding device and a motor A nozzle that feeds out a coil has: a nozzle hole from which the coil is fed out; an inner-diameter round chamfered part formed on an opening edge of a tip of the nozzle; an outer-diameter round chamfered part formed on the outer peripheral edge of the tip of the nozzle. When the wire diameter of the coil is defined as Φc, the inner diameter of the nozzle hole is defined as Φin, the radius of curvature of the inner-diameter round chamfered part is defined as Rin, and the radius of curvature of the outer-diameter round chamfered part is defined as Rout, they satisfy 1.2Φc≤Φin≤1.4Φc, 0.5Φc≤Rin≤Φc, and 0.25Φc≤Rout≤0.5Φc.

Provided are a winding device and a motor A nozzle that feeds out a coil has: a nozzle hole from which the coil is fed out; an inner-diameter round chamfered part formed on an opening edge of a tip of the nozzle; an outer-diameter round chamfered part formed on the outer peripheral edge of the tip of the nozzle. When the wire diameter of the coil is defined as Φc, the inner diameter of the nozzle hole is defined as Φin, the radius of curvature of the inner-diameter round chamfered part is defined as Rin, and the radius of curvature of the outer-diameter round chamfered part is defined as Rout, they satisfy 1.2Φc≤Φin≤1.4Φc, 0.5Φc≤Rin≤Φc, and 0.25Φc≤Rout≤0.5Φc.

A plurality of plate-like magnets are positioned in a radial direction and an axial direction and are arranged at a predetermined interval to an inner circumferential surface of a rotor yoke, and a first adhesive is cured, thus forming each partition part that partitions the plate-like magnets from each other and partially bonding the plate-like magnets at a first bonding part, and a second adhesive is cured, thus bonding and fixing the plate-like magnets at a second bonding part while the plurality of plate-like magnets are partitioned from each other at a predetermined interval in a circumferential direction by the partition part.

A plurality of plate-like magnets are positioned in a radial direction and an axial direction and are arranged at a predetermined interval to an inner circumferential surface of a rotor yoke, and a first adhesive is cured, thus forming each partition part that partitions the plate-like magnets from each other and partially bonding the plate-like magnets at a first bonding part, and a second adhesive is cured, thus bonding and fixing the plate-like magnets at a second bonding part while the plurality of plate-like magnets are partitioned from each other at a predetermined interval in a circumferential direction by the partition part.

A motor for an electrical submersible pump includes a stator and rotor, where the rotor is made up of adjacent columns of magnets affixed onto an annular core. End rings on opposite ends of the core provide axial backstops for magnet columns. Thin coaxial sleeves are shrunk fit over the magnets and end rings and that radially compress the magnets. Apertures in a column are formed radially through the core and receive fasteners for securing a guide bar to the core. The guide bar simulates an installed column of magnets to guide placement of adjacent columns of magnets as the guide bar width is substantially the same as a column of magnets, and aperture locations are strategically positioned so that when the guide bar is secured onto the core. After the guide bar is removed the one of the columns of magnets is then adhered to the core.