Electrical hollow conductor for an electromagnetic machine

1. An electromagnetic machine, comprising a magnet unit and a conductor unit electromagnetically interacting with the magnet unit, wherein the conductor unit has at least one electrical conductor, wherein the electrical conductor is in the shape of a tubular body having a hollow interior, wherein the body comprises an electrically conductive material, has an outside diameter and an inside diameter, and is coated with an electrically insulating layer on an outer casing surface of the body, wherein a ratio of the outside diameter to the inside diameter is in a range of 1.25:1 to 4:1, wherein the electrical conductor is wound into a coil, the body is configured as a cylindrical tube, and the outside diameter of the body is in a range of 1.0 mm to 3.2 mm, and wherein the electromagnetic machine further comprises a connecting piece for connecting the electrical conductor and a coolant line, the connecting piece comprising a leak-proof housing having a hollow interior, at least one hollow conductor opening in the housing for receiving an open end of the electrical conductor, and a coolant line opening in the housing for receiving an open end of the coolant line, wherein the hollow interior of the housing is configured so that the hollow interior hydraulically or pneumatically connects the hollow conductor opening and the coolant line opening, wherein the hollow conductor opening has a diameter that is adapted to an outside diameter of a body of the electrical conductor to be received.

2. The electromagnetic machine according to claim 1 , wherein the electromagnetic machine has a cooling unit, wherein the cooling unit comprises a pump and the electrical conductor, wherein the pump is configured to pump a coolant through the electrical conductor.

3. The electromagnetic machine according to claim 1 , wherein the connecting piece has a housing insert, wherein the housing insert is configured to pass through the housing and wherein a hollow interior of the housing insert provides the hollow conductor opening.

4. The electromagnetic machine according to claim 1 , wherein the hollow interior is configured as rounded.

5. The electromagnetic machine according to claim 1 , wherein the connecting piece is configured to connect at least two electrical hollow conductors and the coolant line, wherein the connecting piece comprises at least two hollow conductor openings in the housing for receiving open ends of the electrical conductors, wherein the hollow interior is configured so that the hollow interior hydraulically or pneumatically connects the hollow conductor openings and the coolant line opening, wherein the connecting piece has an electrically conductive contact element and an electrically insulating separator element, wherein the contact element is configured so that the contact element electrically connects at least two hollow conductor openings, and wherein the separator element is arranged in an electrically insulating manner between the contact element and the hollow conductor openings on the one hand and the coolant line opening on the other hand.

6. The electromagnetic machine according to claim 1 , wherein the contact element is the housing and that the separator element is configured as an electrically insulating sleeve passing through the housing, wherein a hollow interior of the electrically insulating sleeve provides the coolant line opening.

7. The electromagnetic machine according to claim 6 , wherein a first group of electrically connected hollow conductor openings is electrically insulated by means of the separator element or by means of another separator element from a second group of electrically connected hollow conductor openings.