ACTUATOR THAT LOCKS IN A MAXIMUM POSITION FOR ACTUATING A HYDRAULIC CLUTCH ACTUATOR, AND CLUTCH SYSTEM THAT CAN BE ELECTRICALLY ACTUATED

The invention relates to an actuator (13) for actuating a piston (17) of a hydraulic clutch actuator and how said el actuator (13) can be used in a hydraulic system of an electrically actuatable clutch system for a motor vehicle. An electric motor (11) drives an actuating disc (55). A slotted guide structure (31) is arranged on the actuating disc (55). The slotted guide structure (31) forms a contact surface (33), the radius (r) of which increases in relation to an axis (65) from a minimum radius point (35) to a maximum radius point (37). An actuating rod (41) is engaged with a piston (17) of the clutch actuator and is supported on the first slotted guide structure (31) and guided in such a way that, with one rotation of the actuating disc (55), a pressure is exerted on the actuating rod (41) by the first slotted guide structure (31). A holding structure (31) is provided on the slotted guide structure, for example in the form of a recess (40), said holding structure being designed in such a way that, as a result of an effect of the holding structure (40), the actuating rod (41) maintains a position