In order to further seal off the rotor core 2, said core has two outer sealing layers (not shown), which are formed by immersing the rotor core twice into a liquid resin material, without the permanent magnets 3a-3d received in the core.

The rotor assembly 1 additionally has a connection element 57, relative to which the shaft 4 is rotatable. The free end 4a of the shaft 4 associated with the first shaft portion 8 leads into the connection element 57 and is fluidically connected to a first feed channel 58 of the termination element 57. In addition, the fluid-guiding portion 11 also leads into the connection element 57 at the free end 4a and is fluidically connected to a second feed channel 59. The feed channels 58, 59 run in a manner axially distanced from one another in the radial direction and lead into a lateral surface of the substantially cylindrical connection element 57. The connection element 57 additionally has cooling fluid connections 60, 61 arranged on its lateral surface, for example in order to connect fluid lines, which feed and discharge the cooling fluid, to the feed channels 58, 59. The connection element 57 additionally has a radial shaft ring seal 62, in which the shaft 4 can rotate.