Rotor shaft, rotor, electrical machine and manufacturing method for a rotor shaft

A rotor shaft comprising:

• a base shaft including a lateral surface having a conical shape,
• a rotor shaft seat configured to support a plate stack, the rotor shaft seat located on an outer lateral surface of the rotor shaft in the area of the base shaft,
• a conical sleeve including a lateral surface having a conical shape, the lateral surface of the conical sleeve facing the lateral surface of the base shaft, the conical shapes of the base shaft and the conical sleeve running opposite each other, the conical shape of the base shaft and the conical shape of the conical sleeve each having an angle of less than 1°,
• a first bearing area provided at a longitudinal end of the base shaft and connected to the base shaft in a force-fit, positive mechanical-fit, or material-fit connection;
• and
• a second bearing area provided at a longitudinal end of the conical sleeve;
• wherein an inner diameter of the first and second bearing areas is smaller than an inner diameter of the base shaft in the rotor shaft seat.