Abstract: A rotor shaft (100) for a rotor (132), in particular for an electric machine (130), wherein the rotor shaft (100) has a base shaft (102), and wherein a rotor shaft seat (106) for a plate stack (108) is formed on an outer lateral surface (114, 116) of the rotor shaft (100) in the area of the base shaft (102), wherein the rotor shaft (100) comprises a conical sleeve (104), wherein a lateral surface (110) of the base shaft (102) facing the conical sleeve (104) comprises a conical shape which runs opposite to a conical shape of the lateral surface (112) of the conical sleeve (104) facing the base shaft (102). Furthermore, a corresponding rotor and a corresponding electric machine are disclosed, as well as a method for manufacturing such a rotor shaft (100).

Abstract: A balance shaft for balancing forces of inertia and/or moments of inertia of a reciprocating-piston internal combustion engine, including: at least one elongate main body; at least one bearing seat, disposed on the elongate main body for the mounting of a radial bearing. In the center point of the bearing seat there is provided the rotational axis of the balance shaft. The elongate main body may be formed of an integral tubular element, and the center of mass of the elongate main body may lie outside the rotational axis of the balance shaft.

Abstract: A balance shaft for balancing forces of inertia and/or moments of inertia of a reciprocating-piston internal combustion engine, including: at least one elongate main body; at least one bearing seat, disposed on the elongate main body for the mounting of a radial bearing. In the center point of the bearing seat there is provided the rotational axis of the balance shaft. The elongate main body may be formed of an integral tubular element, and the center of mass of the elongate main body may lie outside the rotational axis of the balance shaft.