An electric machine including a rotor shaft having an inner shaft core with a first composition and an outer shaft portion surrounding at least some of the inner shaft core. The outer shaft portion is fabricated from a material having a different composition than the inner shaft core. For example, the inner shaft core could be fabricated from a material having high thermal conductivity, such as copper, while the outer shaft portion is fabricated from a material with lesser thermal conductivity, but greater strength, for example steel. The two-material shaft with a highly thermally conductive core serves to conduct heat from the interior of the electric machine to the housing, or to an exterior apparatus or structure.

The present invention relates to a stator core for improving the fixing properties of a magnet wire, and a motor in which the same is applied. Provided is a stator core which comprises a protrusion pattern part for fixing the distal end portion of a magnet wire, and thus eliminates a process of fixing the wire using a separate member during a wiring process, thereby improving processability and inhibiting an insulating film of the magnet wire from being damaged by an external force such as vibration.

The present invention relates to a stator core for improving the fixing properties of a magnet wire, and a motor in which the same is applied. Provided is a stator core which comprises a protrusion pattern part for fixing the distal end portion of a magnet wire, and thus eliminates a process of fixing the wire using a separate member during a wiring process, thereby improving processability and inhibiting an insulating film of the magnet wire from being damaged by an external force such as vibration.

An electric machine including a shaft, a rotor back assembly surrounding a portion of the shaft, and two or more permanent magnets radially positioned around the perimeter of the rotor back assembly. The electric machine also includes a rotor fan with multiple fan blades formed in an exterior surface of the rotor back assembly and one or more ventilation channels extending through the rotor back assembly. Methods of exporting heat from an electric machine, wither from a machine housing or through the shaft is also disclosed. The heat exportation methods feature the circulation of a fluid with the rotor fan through the ventilation channels and into contact with the housing, or exporting heat from the rotor back assembly through the shaft.

An electric machine including a shaft, a rotor back assembly surrounding a portion of the shaft, and two or more permanent magnets radially positioned around the perimeter of the rotor back assembly. The electric machine also includes a rotor fan with multiple fan blades formed in an exterior surface of the rotor back assembly and one or more ventilation channels extending through the rotor back assembly. Methods of exporting heat from an electric machine, wither from a machine housing or through the shaft is also disclosed. The heat exportation methods feature the circulation of a fluid with the rotor fan through the ventilation channels and into contact with the housing, or exporting heat from the rotor back assembly through the shaft.

A motor includes a stator having a winding, and a rotor. The rotor rotates by receiving a rotational magnetic field generated by drive current supplied to the winding. The winding includes a first winding and a second winding, the first and second windings both being excited at the same timing by the drive current. The first winding and the second winding are connected in series. The rotor includes a first pole section and a second pole section. The second pole section faces the second winding at the rotation position of the rotor at which the first pole section faces the first winding. The magnetic force exerted on the stator by the second pole section is weaker than that exerted by the first pole section.

A mandrel formed of urethane is inserted into a hollow shaft and is compressed axially by a die and a pad. The shaft is then fit in a shaft through hole of a rotor core. Thereafter, compression of the mandrel is released or reduced, and the mandrel is removed from the shaft. Thus, in fitting the hollow shaft in the shaft through hole of the rotor core, deformation of the shaft is reduced.

An electric submersible pump (ESP) that has a motor section for driving the ESP. The motor section has a stator has an inner surface, winding channels disposed axially therein and windings disposed in the winding channels to generate an electromagnetic field when power is supplied to the ESP. The motor section also has a rotor rotatably disposed in the stator. The rotor has permanent magnets or induction windings disposed therein that are responsive to the electromagnetic field to facilitate rotation of the rotor relative to the stator. The motor section also includes a manipulated air gap disposed between the rotor and the stator that the electromagnetic field crosses. The manipulated air gap provides a desired constant radially directed load on the rotor to stabilize the rotor when instability of the motor section occurs. A method of designing and constructing the ESP disclosed herein. To design and construct the ESP, a desired constant radially directed load is determined for an electric submersible pump (ESP) to stabilize the ESP when instability of an electromagnetic field of the ESP occurs. The air gap is manipulated to achieve the desired constant radially directed load or the design of a stator of the ESP is manipulated to achieve the desired constant radially directed load. The ESP can then be constructed.

An electric submersible pump (ESP) that has a motor section for driving the ESP. The motor section has a stator has an inner surface, winding channels disposed axially therein and windings disposed in the winding channels to generate an electromagnetic field when power is supplied to the ESP. The motor section also has a rotor rotatably disposed in the stator. The rotor has permanent magnets or induction windings disposed therein that are responsive to the electromagnetic field to facilitate rotation of the rotor relative to the stator. The motor section also includes a manipulated air gap disposed between the rotor and the stator that the electromagnetic field crosses. The manipulated air gap provides a desired constant radially directed load on the rotor to stabilize the rotor when instability of the motor section occurs. A method of designing and constructing the ESP disclosed herein. To design and construct the ESP, a desired constant radially directed load is determined for an electric submersible pump (ESP) to stabilize the ESP when instability of an electromagnetic field of the ESP occurs. The air gap is manipulated to achieve the desired constant radially directed load or the design of a stator of the ESP is manipulated to achieve the desired constant radially directed load. The ESP can then be constructed.

An electric machine including a shaft, a rotor back assembly surrounding a portion of the shaft, and two or more permanent magnets radially positioned around the perimeter of the rotor back assembly. The electric machine also includes a rotor fan with multiple fan blades formed in an exterior surface of the rotor back assembly and one or more ventilation channels extending through the rotor back assembly. Methods of exporting heat from an electric machine, wither from a machine housing or through the shaft is also disclosed. The heat exportation methods feature the circulation of a fluid with the rotor fan through the ventilation channels and into contact with the housing, or exporting heat from the rotor back assembly through the shaft.