Abstract: A rotor (1) of an electrical machine is already known, comprising a rotor body (3) which can be rotated about a rotor axis (2) and comprising several cooling ducts (5) which have a cooling duct opening (8.1, 8.2) at each of its ends, wherein one cooling duct opening (8.1) of one of the cooling ducts (5) is arranged radially further outside than the other cooling duct opening (8.2) of the same cooling duct (5). The driving force for generating an airflow through the cooling ducts (5) is generated by a radial offset between a channel of a hollow shaft of the rotor and one of the cooling duct openings of the rotor. In the rotor (1) according to the invention, the driving force for generating the airflow is generated solely in the cooling duct (5) in question of the rotor (1). According to the invention: the first cover element (10) covers the radially innermost partial cross-section of the cooling duct opening (8.

Abstract: A rotor (1) of an electrical machine is already known, comprising a rotor body (3) which can be rotated about a rotor axis (2) and comprising several cooling ducts (5) which have a cooling duct opening (8.1, 8.2) at each of its ends, wherein one cooling duct opening (8.1) of one of the cooling ducts (5) is arranged radially further outside than the other cooling duct opening (8.2) of the same cooling duct (5). The driving force for generating an airflow through the cooling ducts (5) is generated by a radial offset between a channel of a hollow shaft of the rotor and one of the cooling duct openings of the rotor. In the rotor (1) according to the invention, the driving force for generating the airflow is generated solely in the cooling duct (5) in question of the rotor (1). According to the invention: the first cover element (10) covers the radially innermost partial cross-section of the cooling duct opening (8.

Abstract: The present invention relates to a clamping device for clamping tools, having a receptacle (2) that is surrounded by an annular space (3). The annular space (3) is open toward the workpiece-side end surface (1a) of the chuck body (1) and toward the receptacle (2), and is closed off by an cover (5). Configured in the receptacle-side inner wall of the cover (5) is an annular groove (13) in which a sealing ring (12) is arranged; a liquid can be delivered to the annular groove (13) in order to press inward the sealing ring (12) that is inserted into the annular groove (13) and thus actively seal a gap formed between the cover (5) and a tool (W) inserted into the receptacle (2).