Rotor device for an electric machine including a cooling fluid line, a collecting ring, and an adapter

A rotor device for an electric machine, comprising:

• a rotor which comprises a laminated rotor core that comprises a plurality of pole limbs which project radially from a central axis of the rotor and around which respective rotor windings can be wound;
• at least one cooling fluid line which extends in a circumferential direction between adjacent pole limbs with its direction of longitudinal extent parallel to the central axis of the rotor and which is configured such that a cooling fluid flows through it for cooling the rotor;
• and
• at least one collecting ring that is arranged on an end face of the rotor and which is designed to collect cooling fluid flowing along the end face and to provide the cooling fluid for the at least one cooling fluid line,
• wherein the collecting ring for the at least one cooling fluid line has a fluid opening in which an adapter is inserted, the adapter being designed to supply the cooling fluid collected by the collecting ring to the respective cooling fluid line adjoining the adapter, and
• wherein the adapter has a slot which is designed to form a form fit with a rotor potting compound of the rotor.