A rotor of a motor according to the present invention comprises: a shaft; a rotor core having a shaft insertion hole, into which the shaft is inserted and coupled; a magnet coupled to the outer peripheral surface of the rotor core; and a rotor cover comprising an upper cap and a lower cap, which cover the upper and lower portions of the rotor core and of the magnet, respectively, wherein the outer periphery of the rotor core comprises a first corner portion and a second corner portion, and the inner periphery of the magnet comprises a first inner peripheral portion, which corresponds to the first corner portion, and a second inner peripheral portion, which corresponds to the second corner portion.

A molding-on tool for producing a rotor, the rotor having a plurality of stacks, which are stacked one over the other in the axial direction and each have a magnet carrier and a plurality of magnets fastened thereto. Plastic is molded onto the magnets in order to fix the position on the magnet carrier, the molding-on tool having at least two molding-on plates, which are provided for feeding plastic in order to mold plastic onto the magnets.

A molding-on tool for producing a rotor, the rotor having a plurality of stacks, which are stacked one over the other in the axial direction and each have a magnet carrier and a plurality of magnets fastened thereto. Plastic is molded onto the magnets in order to fix the position on the magnet carrier, the molding-on tool having at least two molding-on plates, which are provided for feeding plastic in order to mold plastic onto the magnets.

An insulating composition having a polymer resin, a nanoclay, and one or more nanofillers. The insulating composition has a thermal conductivity of greater than about 0.8 W/mK, a dielectric constant of less than about 5, a dissipation factor of less than about 3%, and a breakdown strength of greater than about 1,000V/mil. The insulating composition has an endurance life of at least 400 hours at 310 volts per mil.

An insulating composition having a polymer resin, a nanoclay, and one or more nanofillers. The insulating composition has a thermal conductivity of greater than about 0.8 W/mK, a dielectric constant of less than about 5, a dissipation factor of less than about 3%, and a breakdown strength of greater than about 1,000V/mil. The insulating composition has an endurance life of at least 400 hours at 310 volts per mil.

A rotor includes a rotor core, a first magnet, a second magnet, and a holder made of resin. Both a radially inner surface and a radially outer surface of the first magnet are covered with the rotor core. The second magnet includes a radially inner surface covered with the rotor core, and a radially outer surface exposed from the rotor core. The holder includes a first inner pressing portion and a second inner pressing portion. The first inner pressing portion presses the first magnet radially outward from a radially inner side of the first magnet. The second inner pressing portion presses the second magnet radially outward from a radially inner side of the second magnet. Accordingly, the first magnet and the second magnet are accurately positioned for the rotor core.

A rotor includes a rotor core, a first magnet, a second magnet, and a holder made of resin. Both a radially inner surface and a radially outer surface of the first magnet are covered with the rotor core. The second magnet includes a radially inner surface covered with the rotor core, and a radially outer surface exposed from the rotor core. The holder includes a first inner pressing portion and a second inner pressing portion. The first inner pressing portion presses the first magnet radially outward from a radially inner side of the first magnet. The second inner pressing portion presses the second magnet radially outward from a radially inner side of the second magnet. Accordingly, the first magnet and the second magnet are accurately positioned for the rotor core.

Impregnation plant for internally hollow cylindrical components (stators) of electric motors including working stations arranged linearly and sequentially, managed and controlled by central processing unit; and a plurality of motor-driven elements to impart rotatory motion, in both directions of rotation, and tilting motion, in both directions respective to a predefined plane, to each component mounted onto a respective support device when such support device is inserted into the plant working stations. Each support device has a spring collet in turn has blocks clamping the component onto the inner diameter of its respective cylindrical body. Each spring collet entirely crosses the component cylindrical body to rest on both of its respective circumferential ends. An impregnation method for electric motor components using the impregnation plant, wherein the component is rotatable in both directions about a support device predefined axis, and tiltable respective to a predefined plane of such support device.

Impregnation plant for internally hollow cylindrical components (stators) of electric motors including working stations arranged linearly and sequentially, managed and controlled by central processing unit; and a plurality of motor-driven elements to impart rotatory motion, in both directions of rotation, and tilting motion, in both directions respective to a predefined plane, to each component mounted onto a respective support device when such support device is inserted into the plant working stations. Each support device has a spring collet in turn has blocks clamping the component onto the inner diameter of its respective cylindrical body. Each spring collet entirely crosses the component cylindrical body to rest on both of its respective circumferential ends. An impregnation method for electric motor components using the impregnation plant, wherein the component is rotatable in both directions about a support device predefined axis, and tiltable respective to a predefined plane of such support device.

A stator has a stator coil provided on an annular stator core. The stator coil is formed of electrical conductor wires each including an electrical conductor and an insulating coat. Each of the electrical conductor wires has a pair of exposed portions where the electrical conductor is exposed from the insulating coat and a covered portion where the electrical conductor is covered with the insulating coat. The pair of exposed portions are formed respectively at opposite end portions of the electrical conductor wire. The covered portion is formed at other portions of the electrical conductor wire than the end portions. At a coil end part of the stator coil, each corresponding pair of the exposed portions of the electrical conductor wires are welded together and each of the covered portions of the electrical conductor wires includes a coat-removed portion where the insulating coat is locally removed from the covered portion.