A rotor has a rotor body having: a flange with a circumferential array of discontiguous apertures; and a surface spaced apart from the flange. One or more rotor balance weight assemblies each have a weight and a fastener. The weight has: a passageway having a first end and a second end; an internal thread along the passageway; and a boss at the first end of the passageway. The boss is in a respective one of the apertures. The fastener has: a shank having a first end and a second end and an external thread engaged to the passageway internal thread; an engagement feature at the shank first end for engagement by a tool to turn the fastener; and a head at the second end contacts the surface.

A rotor according to an embodiment includes a cylindrical magnet, a holder, and a balance adjusting portion. The cylindrical magnet has a bore portion into which a rotary shaft is inserted, the inner diameter of the bore portion being larger than the outer diameter of the rotary shaft. The holder is made of resin, and has a tubular portion formed in the bore portion of the magnet and a protruding portion protruding from the magnet in the rotation axis direction, the holder being press-fitted onto the rotary shaft. The balance adjusting portion is press-fitted onto the rotary shaft with the protruding portion interposed therebetween.

A rotor (1) comprising a rotor shaft (13), a rotor core (14) having a core length, windings (12), and two impregnation rings (11), the windings (12) forming protruding windings ends (121), each one of the two impregnation rings (11) comprising an annular portion (111) and a deflector portion (112), the annular portion (111) comprising radial openings (113); and a method for impregnating the rotor (1) comprising starting a rotation of the rotor shaft (13) and impregnating the windings (12) with an impregnating agent through two nozzles respectively located upward each one of the two impregnation rings (11) and oriented towards the radial openings (113), the impregnation agent being guided by the deflector portion (112) towards the protruding windings ends (121) on both sides of the rotor (1) at a same time, in order to impregnate the windings (12) through the core length.

A rotor sheet includes a central cut-out and is divided into a plurality of sectors, each including a first half sector and a second half sector delimited from the first half sector by a radial central line, wherein a through-opening configuration, which has two parallel edge lines extending along an extension direction, is formed inside the first half sector, and a further through-opening configuration, mirror-symmetrical to the through-opening configuration with respect to the central line, is formed inside the second half sector, wherein the first through-opening configuration includes a relief through-opening inscribed inside an incircle-free trapezoid having two bases extending parallel to the central line and two legs extending on a first straight line having a first angular spacing from the central line, and on a second straight line having a second angular spacing from the central line, wherein the first and second straight lines intersect at an acute angle.

A rotor for an electrical machine includes a rotor core having a plurality of circumferentially spaced apart rotor poles. Windings are seated in gaps between circumferentially adjacent pairs of the rotor poles. A wedge secures the windings in each gap. The wedge includes a first member made of a first material and at least one second member made of a second material. The second material has a higher electrical conductivity than the first material. The wedge is configured to supply Q-axis damping. A pair of end plates is connected electrically to the at least one second member at opposing longitudinal ends thereof thereby completing a Q-axis winding circuit for each wedge.

Disclosed herein is a method for forming a rotor or stator core. The method includes the steps of: providing a plurality of key punches disposed about an inner diameter area of a sheet of electrical steel and circumferentially spaced from one another and activating a first key punch of the plurality of key punches to cut the electrical steel sheet to remove a portion to form a first key disposed at a first key rotational angle from the line of orientation from a plurality of key rotational angles.

Systems and methods for cooling power transmission systems are include providing oil through an aperture defined in a housing to a stator cooling ring, through the stator cooling ring and into stator cooling channels, through the stator cooling channels and into spaces defined between the housing and jet rings, and through holes in the jet rings and onto the end-windings. The stator cooling ring, stator cooling channels and jet rings can encircle the stator and end-windings and, via the holes in the jet rings, spray pressurized jets of oil from various angles onto the end-windings, and in particular middle regions thereof. Seals may be used between the jet rings and housing, and between the jet rings and stator ends. The seals may be compressed so as to form an interference fit between the jet rings and housing or stator ends as the case may be.

A balancing machine drive apparatus for driving rotational movement of a workpiece rotatably mounted about a rotational axis by a looping belt includes a frame at least partially surrounding, transaxially to the rotational axis, a workpiece mounting position and having an opening closable by an arch and through which the mounting position is accessible, the drive apparatus including guide devices on the frame and/or arch to guide the belt such that, when the arch is closed, the belt winds at least partially around a workpiece in the mounting position on a cylindrical circumferential workpiece region, and a drive device for the belt. The arch is held on the frame so as to be movable between open and closed positions. A balancing machine for balancing a workpiece includes a mounting apparatus in order to rotatably mount the workpiece about a rotational axis in a mounting position, and the drive apparatus.

A method for producing a rotor device, including providing a rotor shaft having at least one sheet metal packet joined to the rotor shaft. The at least one sheet metal packet includes magnetic units. The method includes performing a transfer molding process, in which the magnetic units are fixed in position in relation to the at least one sheet metal packet and at least one balancing disk is joined axially on the rotor shaft on at least one side of the at least one sheet metal packet such that a gap of a defined width is ensured between the at least one balancing disk and the at least one sheet metal packet. The gap is filled with a molding compound used for the transfer molding process. The method includes determining an imbalance of the rotor device and compensating the imbalance by removing material from the at least one balancing disk.

An excitation system (15) is disclosed for providing excitation to a main rotating electrical machine (2). The excitation system comprises an exciter (50) and an auxiliary generator (52). The exciter and the auxiliary generator have separate stator cores (14, 18) and share a common rotor core (16). The common rotor (16) core may be located between the two stator cores (14, 18). This may help to optimize space, improve material usage and reduce the total rotating mass. A mounting arrangement for the common rotor core is also disclosed.