Method and device for actuating a dog clutch of a gearbox of an electrically driveable vehicle
A method and a device for actuating a dog clutch ( 6 ) of a gearbox ( 2 ) of an electrically driveable vehicle ( 1 ) determines at least relative rotational speeds and/or rotational angle positions of a sliding sleeve ( 7 ) and of a coupling element ( 12 ) relative to each other, in order to avoid a possible tooth-to-tooth position. In the case of a predicted tooth-to-tooth position, control measures are carried out, which change the relative rotational angle position of the sliding sleeve ( 7 ) and of the coupling element ( 12 ) relative to each other and/or the duration of the movement of the sliding sleeve ( 7 ) in such a way that, when an engagement position is reached, delay-free form-fitting meshing of associated sets of dog teeth ( 10, 13 ) is carried out.
1 . 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.
2 . The method according to claim 1 , wherein the meshing of the sets of dog teeth is delay-free.
3 . The method according to claim 1 , wherein the control measures change the relative rotational angle positions of the sliding sleeve ( 7 ) and of the coupling element ( 12 ) relative to each other in such a way that when the engagement position is reached, the form-fitting meshing of the sets of dog teeth ( 10 , 13 ) is carried out.
4 . The method according to claim 3 , wherein the control measures also change a duration of the movement of the sliding sleeve ( 7 ) during a switching operation in such a way that when the engagement position is reached, the form-fitting meshing of the sets of dog teeth ( 10 , 13 ) is carried out.
5 . The method according to claim 1 , wherein the control measures change a duration of the movement of the sliding sleeve ( 7 ) during a switching operation in such a way that when the engagement position is reached, the form-fitting meshing of the sets of dog teeth ( 10 , 13 ) is carried out.
6 . The method according to claim 1 , wherein in the case of a predicted tooth-to-tooth position, a rotational speed of the input shaft ( 3 ) is changed by way of changing a rotational speed of the electric drive machine ( 5 ) such that a rotational angle position of the sliding sleeve ( 7 ) co-rotationally connected to the input shaft ( 3 ) permits delay-free meshing of the first dog teeth of the sliding sleeve ( 7 ) and the second dog teeth of the coupling element ( 12 ) when they reach the engagement position.
7 . The method according to claim 1 , wherein in the case of a predicted tooth-to-tooth position, initially starting from the time of actuation of the sliding sleeve ( 7 ) a new engagement time is calculated at which the rotational angle positions of the sliding sleeve ( 7 ) and the coupling element ( 12 ) relative to each other permit the first and second dog teeth ( 10 , 13 ) to mesh.
8 . The method according to claim 7 , wherein a new actuating speed curve of the sliding sleeve ( 7 ) matched to the new engagement time is then calculated.
9 . The method according to claim 8 , wherein the sliding sleeve ( 7 ) is then displaced axially by way of the electric actuator ( 16 ) in accordance with the calculated new actuating speed curve in order, when the engagement position is reached, to mesh the first dog teeth ( 10 ) of the sliding sleeve ( 7 ) without delay in the second dog teeth ( 13 ) of the coupling element ( 12 ) in a form-fitting manner.
10 . The method according to claim 9 , wherein, starting from the time of actuation of the sliding sleeve, an actuating speed of the sliding sleeve rises linearly as the sliding sleeve approaches the engagement position.
11 . The method according to claim 10 , wherein, at the engagement position, the sliding sleeve engages the coupling element without delay.
12 . The method according to claim 11 , wherein, after engagement, the actuating speed of the sliding sleeve continues to rise linearly.
13 . The method according to claim 1 , wherein the meshing of the sets of dog teeth is carried out without braking the sliding sleeve.
14 . The method according to claim 1 , wherein a time to achieve meshed engagement is shorter relative to a non-linear actuating speed curve of the sliding sleeve having braking and a neutral position state of the sliding sleeve at the engagement position.
15 . The method according to claim 1 , wherein the actuating speed curve of the sliding sleeve is substantially linear and constant.
16 . A vehicle ( 1 ) having an electric drive and a device ( 17 ) for actuating the dog clutch ( 6 ) of the gearbox ( 2 ), wherein the device ( 17 ) carries out the method according to claim 1 .
17 . A device ( 17 ) 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 ), the device comprising:
a sliding sleeve ( 7 ) co-rotationally and axially displaceably arranged on the input shaft ( 3 ) or another transmission shaft that is connected to the input shaft ( 3 ) and has first dog teeth ( 10 ), wherein
a coupling element ( 12 ) rotatably arranged on the input shaft 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 that is connected to the output shaft ( 4 );
wherein the coupling element has second dog teeth ( 13 ),
wherein the sliding sleeve ( 7 ) is axially movable by way of a switching element ( 15 ) which is actuated by an electric actuator ( 16 ) in order to produce a form-fitting connection to the coupling element ( 12 ),
a sensor device ( 18 ) which is configured for direct and/or indirect detection of rotational angle positions and/or rotational speeds of the sliding sleeve ( 7 ) and of the coupling element ( 12 ) from sensor measured values and/or from control data of the electric drive machine ( 5 ),
an electronic control device ( 20 ), which is configured to evaluate the detected rotational angle positions and/or rotational speed of the sliding sleeve ( 7 ) and of the coupling element ( 12 ) and to control the electric drive machine ( 5 ) and the electric actuator ( 16 ) as a function of the rotational speed values and/or rotational angle position values;
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.
18 . A vehicle ( 1 ) having an electric drive and the device ( 17 ) for actuating the dog clutch ( 6 ) of the gearbox ( 2 ) according to claim 17 .