Abstract: An electrical contact arrangement comprising at least one pair of contacts which is formed by a primary and a secondary contact ring (11, 12) which can be rotated in relation to one another about a longitudinal center axis (16) and each have a conical shell-like contact face (11d, 12d) which surrounds the longitudinal center axis (16), and at least one roller (27) which rolls between the primary and the secondary contact ring (11, 12) and is rotatably mounted about a rotation axis (28) which is at a right angle to the longitudinal center axis (16). The roller (27) has a conical shell-like contact surface (27a) which surrounds the rotation axis (28) and respectively forms a line contact, which runs along a respective contact line (31, 32), with the contact faces (11d, 12d) of the primary and secondary contact rings (11, 12).

Abstract: A clamping device for clamping an insertion nipple (7), including a clamping element (11) which can be axially moved, by a drive motor (9) via a screw mechanism (13), between an open position in which the insertion nipple (7) can be introduced into a receiving opening (8) of the clamping device and withdrawn from the same, and a clamping position in which the insertion nipple (7) introduced into the receiving opening (8) is retained in the same. The clamping device has an impulse unit (12) with a rotary part (40) which is mechanically coupled to the rotor (31) of the drive motor (9), and by which, for each revolution, a rotary impulse can be transmitted, at least once, to an impulse-receiving part (41) of the impulse unit (12) via the screw mechanism (13), in order to axially move the clamping element (11).