US Patent 10454329 Electrical hollow conductor for an electromagnetic machine

An electrical hollow conductor (1) in the shape of a tubular body (2) having a hollow interior (3) for continuously winding an electromagnetic coil, wherein the body (2) comprises an electrically conductive material, has an outside diameter and an inside diameter, wherein a ratio of the outside diameter to the inside diameter is in a range of 1.25:1 to 4:1, and is coated with an electrically insulating layer (4) on an outer casing surface of the body (2) and wherein the interior (3) is configured so that it hydraulically or pneumatically connects a first open end of the body (2) and a second open end of the body (2).