US-12624758-B2 - Method for operating a motor vehicle drive train device for a motor vehicle and corresponding motor vehicle drive train device

US12624758B2US 12624758 B2US12624758 B2US 12624758B2US-12624758-B2

Abstract

A method for operating a motor vehicle drive train device for a motor vehicle, which includes a motor, connected at least temporarily to at least one wheel of the motor vehicle via a torque transmission assembly, and a park lock device. The park lock device form-fittingly fixes a locking element coupled in a rotationally fixed manner to the torque transmission assembly in a first setting and releases in a second setting and, when the park lock device is switched from the first setting to the second setting, a compensating torque is generated on the locking element by the motor, which compensating torque counteracts a tensioning torque by a tensioning of the torque transmission assembly when the locking element is fixed. The compensating torque is determined from a torsional angle of the torque transmission assembly determined after fixing of the locking element and a torsional stiffness of the torque transmission assembly.

Inventors

Lutz Gundlach
Jürgen Kiesewetter
Enrico Szeppat

Assignees

AUDI AG

Dates

Publication Date: 20260512
Application Date: 20230929
Priority Date: 20221006

Claims (20)

1 . A method for operating a motor vehicle drive train device for a motor vehicle, which has a motor, which is connected at least temporarily to at least one wheel of the motor vehicle via a torque transmission assembly, and a park lock device, wherein the park lock device form-fittingly fixes a locking element coupled in a rotationally fixed manner to the torque transmission assembly in a first setting and releases it in a second setting and, when the park lock device is switched from the first setting to the second setting, a compensating torque is generated on the locking element by means of the motor, which counteracts a tensioning torque caused by a tensioning of the torque transmission assembly when the locking element is fixed, wherein the compensating torque is determined from a torsional angle of the torque transmission assembly determined after the locking element has been fixed and a torsional stiffness of the torque transmission assembly.
2 . The method according to claim 1 , wherein the torque transmission assembly comprises a gearbox that comprises the park lock device.
3 . The method according to claim 2 , wherein the torsional angle is measured by a torsional pulse generator.
4 . The method according to claim 2 , wherein a torsional pulse generator measuring a rotational speed of the wheel is used as the torsional pulse generator.
5 . The method according to claim 2 , wherein a longitudinal acceleration of the motor vehicle is additionally taken into account when determining the compensating torque.
6 . The method according to claim 2 , wherein a torsional angle difference between a first torsional angle of the torque transmission assembly present when the locking element is fixed and a second torsional angle of the torque transmission assembly present before the locking element is released is used as the torsional angle.
7 . The method according to claim 1 , wherein the torsional angle is measured by a torsional pulse generator.
8 . The method according to claim 7 , wherein the torsional pulse generator measuring a rotational speed of the wheel is used as the torsional pulse generator.
9 . The method according to claim 7 , wherein a longitudinal acceleration of the motor vehicle is additionally taken into account when determining the compensating torque.
10 . The method according to claim 7 , wherein a torsional angle difference between a first torsional angle of the torque transmission assembly present when the locking element is fixed and a second torsional angle of the torque transmission assembly present before the locking element is released is used as the torsional angle.
11 . The method according to claim 1 , wherein a torsional pulse generator measuring a rotational speed of the wheel is used as the torsional pulse generator.
12 . The method according to claim 11 , wherein a longitudinal acceleration of the motor vehicle is additionally taken into account when determining the compensating torque.
13 . The method according to claim 11 , wherein a torsional angle difference between a first torsional angle of the torque transmission assembly present when the locking element is fixed and a second torsional angle of the torque transmission assembly present before the locking element is released is used as the torsional angle.
14 . The method according to claim 1 , wherein a longitudinal acceleration of the motor vehicle is additionally taken into account when determining the compensating torque.
15 . The method according to claim 14 , wherein a torsional angle difference between a first torsional angle of the torque transmission assembly present when the locking element is fixed and a second torsional angle of the torque transmission assembly present before the locking element is released is used as the torsional angle.
16 . The method according to claim 1 , wherein a torsional angle difference between a first torsional angle of the torque transmission assembly present when the locking element is fixed and a second torsional angle of the torque transmission assembly present before the locking element is released is used as the torsional angle.
17 . The method according to claim 1 , wherein the determination of the torsional angle is carried out from the fixing of the locking element until immediately before the release of the locking element.
18 . The method according to claim 1 , wherein the torsional angle is determined integrally from a signal of a torsional pulse generator and a longitudinal acceleration.
19 . The method according to claim 1 , wherein, when a control device carrying out the determination of the torsional angle is switched off with the locking element fixed, an instantaneous value of the torsional angle is stored and, when the control device is switched on, the determination of a holding angle is continued on the basis of the stored value.
20 . A motor vehicle drive train device for a motor vehicle, which comprises a motor, connected at least temporarily to at least one wheel of the motor vehicle via a torque transmission assembly, and a park lock device, wherein the park lock device form-fittingly fixes a locking element coupled in a rotationally fixed manner to the torque transmission assembly in a first setting and releases it in a second setting and, when the park lock device is switched from the first setting to the second setting, a compensating torque is generated on the locking element by the motor, which counteracts a tensioning torque caused by tensioning of the torque transmission assembly when the locking element is fixed, wherein the motor vehicle drive train device is provided and configured to determine the compensating torque from a torsional angle of the torque transmission assembly determined after fixing of the locking element and a torsional stiffness of the torque transmission assembly.

Description

FIELD The invention relates to a method for operating a motor vehicle drive train device for a motor vehicle, which comprises a motor, connected at least temporarily to at least one wheel of the motor vehicle via a torque transmission assembly, and a park lock device, wherein the park lock device form-fittingly fixes a locking element coupled in a rotationally fixed manner to the torque transmission assembly in a first setting and releases it in a second setting and, when the park lock device is switched from the first setting to the second setting, a compensating torque is generated on the locking element by means of the drive unit, which compensating torque counteracts a tensioning torque caused by a tensioning of the torque transmission assembly when the locking element is fixed. The invention also relates to a motor vehicle drive train device for a motor vehicle. BACKGROUND Publication DE 10 2010 011 557 A1, for example, is known from the state of the art. This describes a motor vehicle drive train device with a park lock device, which is provided to at least partially form-fittingly lock a motor vehicle drive train, and with a control and/or regulating unit, which is provided to set a defined drive torque in at least one operating state. It is provided that the control and/or regulating unit is intended to set a compensation drive torque provided for reducing a drive train tensioning torque in order to release the park lock device. Furthermore, the publication DE 10 2019 219 670 A1 discloses a transmission device for a motor vehicle, comprising a park lock device which is configured to lock a moving element of the transmission device at least temporarily and/or as required in an engaged state of the park lock device and to release it in a disengaged state of the park lock device, wherein the transmission device is configured for this purpose, to generate a defined torque by means of an electric machine assigned to the transmission device in order to deploy the park lock device, wherein the transmission device is configured to cancel a coupling of a locking element of the transmission device to the corresponding element to be locked by generating the defined torque, wherein the park lock device is configured to transfer at least one locking element into the deployed state when the defined torque is present. SUMMARY The objective of the invention is to propose a method for operating a motor vehicle drive train device for a motor vehicle which comprises advantages over known methods, in particular determines the equalising torque with high accuracy, so that a jolting release of the torque transmission assembly is avoided when the park lock device is released, that is, when the locking element is released by the park lock device. According to the invention, this is achieved with a method for operating a motor vehicle drive train device for a motor vehicle. It is provided that the compensating torque is determined from a torsional angle of the torque transmission assembly determined after fixing of the locking element and a torsional stiffness of the torque transmission assembly. It should be noted that the exemplary embodiments explained in the description are not limiting; rather, any variations of the features disclosed in the description, the claims and the figures can be realised. The method described is used to operate the motor vehicle drive train device. The motor vehicle drive train device is preferably a component of the motor vehicle, but can of course also be present separately from it. The motor vehicle drive train device is used for establishing, at least temporarily, a drive connection between the wheel of the motor vehicle and a drive device of the motor vehicle. The drive device is used to drive the motor vehicle, in this respect therefore to provide a drive torque directed towards driving the motor vehicle. To provide the drive torque, the drive device comprises at least one drive unit, which is configured, for example, as an internal combustion engine or as an electric machine or electric traction machine. The drive device is at least temporarily connected to the at least one wheel of the motor vehicle via the torque transmission assembly of the motor vehicle drive train device, so that a torque, in particular the drive torque, is transmitted between the drive device and the wheel. The torque transmission assembly is any arrangement by means of which the torque can be transmitted between the drive device and the wheel of the motor vehicle. In the simplest case, the torque transmission assembly is a shaft. Particularly preferably, the torque transmission assembly comprises a gearbox by means of which different gears or ratios can be set between the drive unit and the wheel. In addition to the torque transmission assembly, the vehicle drive train device comprises the engine. The motor is preferably a component of the drive device already mentioned, so that in this case the motor vehicle dri