ELECTRIC MASCHINE IN A HIGH PROTECTION CATEGORY WITH IMPROVED ROTOR COOLING

摘要

An electric machine has a stator (1) and a rotor shaft (3). The rotor shaft (3) is rotatably mounted about a shaft axis (5) in relation to the stator (1), said axis (5) defining an axial direction, a radial direction and a tangential direction. A rotor (6), which is in electrical co-operation with the stator (1), is arranged on the rotor shaft (3). The rotor (6) has at least one continuous axial rotor channel (8). The stator (1) has a lamination stack (10) that extends over the rotor (6) when viewed in the axial direction. The lamination stack (10) completely surrounds the rotor (6) when viewed on a sectional plane that is orthogonal to the axial direction, forming a closed inner rotor chamber (11) when viewed on the sectional plane. A respective cover (14) is provided on both axial sides of the lamination stack (10). At least one of the covers (14) has a central cavity (15) to allow the passage of the rotor shaft (3). The lamination stack (10) has at least one axial stator channel (12') that runs continuously in the axial direction and that is completely closed when viewed on the sectional plane. The covers (14) are designed in such a way that in conjunction with the lamination stack (10) they form at least one radial channel (16) running in the radial direction. The radial channels (16) connect the axial stator channel(s) (12') to the inner rotor chamber (11) by means of a fluid connection but are otherwise closed. To force convection, an element (17) that acts as a fan is located on the rotor shaft (3) axially within the covers (14).