Abstract: A method of producing the core of an electric motor by providing a stack of laminations of magnetic material. Windows are formed in the laminations for one or more magnetic elements to be placed in each window. Each window has an end edge portion (17) which is to be at the peripheral edge (18) of the lamination of the finished version of the rotor. The laminations originally have an annular radial extension (60-61) and after the core is assembled with end caps, the annular radial extension (60-61) is removed so that the window end edge portions (17) are at the periphery (18) of the laminations. There is a polar peripheral portion (20) between each window and the periphery (18) of the lamination and an intermediate peripheral portion (40) between two adjacent polar peripheral portions, with such intermediate polar portions having reduced electrical conductibility and reduced magnetic permeability.

Abstract: A process for magnetizing the permanent magnets of an electric motor rotor and a process for assembling a hermetic compressor motor, whose stator (30) carries a plurality of coils (40), said rotor being operationally positioned with a determined relative angular position in relation to the stator (30) prior to the energization, from an external current source, of a determined number of coils (40) of said stator (30) with a current pulse having a required intensity to generate a magnetic field which produces a homogeneous magnetization transversely oriented in at least one magnetic sector, said current pulse being maintained during a shorter time than that which impairs the coils of said stator (30).

Abstract: An electric motor rotor with permanent magnets, the rotor including magnets (20) seated against a cylindrical lateral surface (11) of the core (10) of the rotor and a pair of annular caps (40), each cap being seated and affixed to an adjacent end face (12) of the core (10), the annular caps (40) limiting axial displacements of the magnets and defining, for both directions of circumferential displacement, stops for this displacement for each magnet (20), the confronting lateral edges (21) of a pair of consecutive magnets (20) being positioned by the annular caps (40), in order to define a previously established minimum circumferential distance.

Abstract: A wound cover arrangement for an electric motor rotor, said rotor including a core (20), magnets (30) surrounding said core and a cover (10), which is wound around the core, in order to retain said magnets (30) on said core, said arrangement comprising a pair of mold end elements (40), each mounted to an end face portion of the rotor core (20) and to the adjacent end face of at least one of the parts defined by the cover (10) and magnets (30), and which has a peripheral edge portion (41) provided with at least one recess (43) extending towards the rotor axis, the distance between said rotor and the bottom of said recess (43) defining the smallest winding end radius of the cover.