A method includes: (1) providing a rotor for a line start interior permanent magnet motor wherein the rotor has rotor bars slots extending axially along a length of the rotor configured to receive rotor bar material, and magnet slots extending axially along a length of the rotor configured to receive magnetic material; (2) disposing rotor bar material in the rotor bar slots; (3) arranging a first end member on an axial end of the rotor; (4) disposing magnetic material in the magnet slots; (5) magnetizing the magnetic material; and (6) arranging a second end member on the rotor opposite the first end member. The step of arranging the second end member on the rotor occurs after magnetizing the magnetic material.

A lamination pack for a motor and method of forming the lamination pack is provided. The method includes inserting a plurality of conductor bars into a plurality of rotor slots defined by a lamination stack such that opposing bar ends of the conductor bars extend from opposing end faces of the lamination stack, skewing the lamination stack and the conductor bars to a skew angle relative to a rotation axis of the lamination stack, and subsequently bending the bar ends of the conductor bars in opposing radial directions to a locking angle greater than the skew angle, to lock each of the conductor bars in its respective rotor slot. The bent bar ends exert a compressive axial locking force on the lamination stack to prevent axial and radial movement of the laminations in the lamination stack and to prevent axial movement of the conductor bars relative to the lamination stack.

A cage rotor for an electric machine may include a rotor core and an electrically conductive rotor cage arranged around the rotor core, wherein the rotor cage includes carbon nanotubes. An electric machine including such a cage rotor is also disclosed.

The present disclosure provides a rotor structure, an electric motor and a rotor manufacturing method. The rotor structure includes a plurality of rotor sheets (100) and a rotating shaft. The rotor sheets (100) are stacked in sequence along an axial direction of the rotor structure. Each of the rotor sheets (100) is provided with a shaft hole (20), a first slot (111), and first filling slots (121) at both ends of the first slot (111). The first slot (111) extends in a direction of a direct axis (3) of the rotor structure and includes slot sections (1110) at opposite sides of the shaft hole (20). The rotating shaft passes through the shaft hole (20) of the plurality of rotor sheets (100). The first slot (111), the first filling slots (121) and the rotating shaft form a first flux barrier layer (101).

The present disclosure provides a rotor structure, an electric motor and a rotor manufacturing method. The rotor structure includes a plurality of rotor sheets (100) and a rotating shaft. The rotor sheets (100) are stacked in sequence along an axial direction of the rotor structure. Each of the rotor sheets (100) is provided with a shaft hole (20), a first slot (111), and first filling slots (121) at both ends of the first slot (111). The first slot (111) extends in a direction of a direct axis (3) of the rotor structure and includes slot sections (1110) at opposite sides of the shaft hole (20). The rotating shaft passes through the shaft hole (20) of the plurality of rotor sheets (100). The first slot (111), the first filling slots (121) and the rotating shaft form a first flux barrier layer (101).

This squirrel-cage motor rotor includes a plurality of conductor bars provided at regular intervals along the circumferential direction of a rotor core, short-circuit rings connected to ends of the conductor bars, and reinforcement covers having axial-direction surfaces being in contact with axial-direction-end surfaces of the short-circuit rings. The reinforcement covers are enclosed by casting in the short-circuit rings. Holding rings are attached to the outer circumferential surfaces of the flange portions of the reinforcement covers and the outer circumferential surfaces of the short-circuit rings by interference fit.

A rotor core includes a rotor core includes a plurality of rotor core blocks each of which is constituted by stacking annular sheet-like core materials in a direction of sheet thickness of each core material and a plurality of catch recesses circumferentially disposed in an inner circumference of each core material at an interval of a predetermined angle so as to extend radially outward, the catch recesses having respective circumferential dimensions equal to each other and different radial depths. In each rotor core block, a plurality of the core materials is stacked while the catch recesses having an identical configuration are aligned. The rotor core blocks have respective outer peripheries which are shifted from each other according to the depths of the catch recesses caught by a bar-shaped aligning jig when the catch recesses of the rotor core blocks are caught by the aligning jig.

A rotor of an induction motor includes a core assembly including a plurality of core discs formed with a plurality of slots; a plurality of conductive bars passing through the slots, each of the conductive bars having a first end and a second end respectively extended out of a first end surface and a second end surface of the core assembly; a first end ring assembly including a plurality of first conductive rings stacked on each other and penetrated by the first ends of the conductive bars; and a second end ring assembly including a plurality of second conductive rings stacked on each other and penetrated by the second ends of the conductive bars; wherein the first conductive rings and the second conductive rings are respectively welded to the first ends and the second ends of the conductive bars by electron beam welding or laser welding.

A conductor bar of a cage rotor of an asynchronous machine has a longitudinal extension and includes first and second sections in the longitudinal extension. The first section has a hardness which is lower than a hardness of the second section and is realized through soft annealing, brief inductive heating or heating by a flame so as to enable a compression of the first section of the conductor bar by way of axial pressure after axially joining the conductor bar in a slot of a magnetically conductive body of the cage rotor, with the first section abutting an inner wall of the slot of magnetically conductive body of the cage rotor.

An induction rotor assembly includes a laminated stack, conductor bars, a first end ring, and a second end ring. The laminated stack includes a body with a first end, an opposing second end, and an outer circumferential surface extending from the first end to the second end along a longitudinal axis. The conductor bars are disposed within grooves in the outer circumferential surface. Each conductor bar includes a first conductor end and a second conductor end extending beyond the ends of the laminated stack. The first conductor end and the second conductor end of each of the conductor bars includes a serrated surface having serrations. The first end ring and second end ring interlock with the serrated surface of the conductor ends. The conductor bars extend between the first end ring and the second end ring.