Method and device for actuating a dog clutch of a gearbox of an electrically driveable vehicle

A method for actuating a dog clutch (6) of a gearbox (2) of an electrically driveable vehicle (1), wherein the gearbox (2) has an input shaft (3) and an output shaft (4), wherein the input shaft (3) has a drive connection to an electric drive machine (5) of the vehicle (1), wherein a sliding sleeve (7) is co-rotationally and axially displaceably arranged on the input shaft (3) or another transmission shaft connected to the input shaft (3) and has first dog teeth (10), wherein a coupling element (12) is rotatably and axially non-displaceably arranged on the input shaft (3), wherein the coupling element is drivingly coupled with the output shaft (4) or another transmission shaft connected to the output shaft (4), wherein the coupling element (12) has second dog teeth (13), the method comprising:

• axially moving the sliding sleeve (7) by way of a switching element (15) actuated by an electric actuator (16) and producing a form-fitting connection to the coupling element (12) by coupling the first and second dog teeth (11, 13), and
• determining at least relative rotational speeds and/or rotational angle positions of the sliding sleeve (7) and of the coupling element (12) that are rotatable relative to each other, in order to produce the form-fitting connection,
• controlling electronically, as a function of the determined rotational speeds and/or rotational angle positions, the electric drive machine (5) and/or the electric actuator (16) to avoid a tooth-to-tooth position of the first and second dog teeth (10, 13) when the sliding sleeve (7) is displaced to couple the first and second dog teeth (10, 13),
• wherein, to produce the form-fitting connection by coupling of the two sets of dog teeth (10, 13), at the time of the actuation of the sliding sleeve (7), starting from a defined neutral position, the rotational angle positions and the rotational speeds of the sliding sleeve (7) and of the coupling element (12) relative to each other are determined,
• wherein, starting from the time of the actuation of the sliding sleeve (7), calculating an anticipated engagement time relating to meshing of the first dog teeth (10) of the sliding sleeve (7) in the second dog teeth (13) of the coupling element (12) at a defined engagement position by using a predefined actuating speed curve and a previously determined actuating travel of the sliding sleeve (7) between its neutral position and its engagement position,
• calculating anticipated rotational angle positions of the sliding sleeve (7) and of the coupling element (12) relative to each other at the anticipated engagement time,
• predicting a tooth-to-tooth position or no tooth-to-tooth position at the calculated anticipated engagement time by using the anticipated rotational angle positions of the sliding sleeve (7) and of the coupling element (12) relative to each other, and
• wherein, in the case of a predicted tooth-to-tooth position, carrying out control measures on the electric drive machine (5) and/or on the electric actuator (16) actuating the sliding sleeve (7) and avoiding the tooth-to-tooth position as a result of the control measures such that when the engagement position is reached, form-fitting meshing of the sets of dog teeth (10, 13) is carried out.