Method and control unit for operating a switching element of a motor vehicle

Abstract

A method for operating a switching element (10) of a motor vehicle, wherein the switching element (10) has a switching sleeve (12) that can be actuated by an actuator (13) via a switching fork (15), and which is moved translationally from an actual position to a target position by means of the switching fork (15), which is actuated by the actuator (13) in an actuation direction specified for the switching to be performed. After the switching sleeve (12) has been moved from the actual position to the target position, the switching fork (15) is actuated by the actuator (13) in the opposite direction to the actuation direction specified for the switching to be performed, while maintaining the target position of the switching sleeve (12).

Description

[0001] The invention relates to a method for operating a switching element of a motor vehicle. Furthermore, the invention relates to a control unit for carrying out the method.

[0002] DE 10 2018 207 590 A1 discloses a switching element for a motor vehicle. The switching element has a switching sleeve that can be actuated by an actuator via a switching fork. The actuator moves the switching fork, which, depending on its actuation, moves the switching sleeve via a switching fork head. In this way, it is possible to move the switching sleeve translationally from an actual position to a target position by controlling the actuator.

[0003] After the switching sleeve has been moved to its desired position, the actuator is deactivated, meaning it no longer receives an electrical current. This leaves the switching fork in the position through which the switching sleeve was moved into its desired position. As a result, there is permanent contact between the switching fork, particularly its head, and the switching sleeve, which can cause wear.

[0004] There is a need to operate a transmission shift element, which has a shift sleeve actuated by an actuator via a shift fork, with reduced wear. The object of the present invention is to provide a novel method and control unit for operating a motor vehicle shift element. This object is achieved by a method according to claim 1 and by a control unit according to claim 5.

[0005] According to the invention, after the switching sleeve has been moved from the actual position to the target position, the switching fork is actuated via the actuator in the opposite direction to the direction of actuation specified for the switching operation to be carried out, while maintaining the target position of the switching sleeve.

[0006] The present invention proposes that, after the switching sleeve has been moved into its target position, the switching fork is actuated by the actuator in the opposite direction to the direction of actuation required for the switching operation, while maintaining the target position of the switching sleeve. Accordingly, after the switching sleeve has been moved into its target position, the switching fork is slightly displaced in the opposite direction of actuation in order to maintain the target position of the switching sleeve and to prevent permanent contact and thus permanent axial wear of the switching sleeve. This reduces the risk of wear.

[0007] Preferably, after the switching sleeve has been moved from its actual position to its target position, the switching fork is actuated by the actuator in the opposite direction to the direction of actuation specified for the circuit to be executed, such that, as a result of the actuation in the opposite direction to the direction of actuation specified for the circuit to be executed, there is no contact between the switching fork and the switching sleeve. This is particularly preferred in order to reduce the risk of wear.

[0008] Preferably, the switching fork engages in a groove in the switching sleeve and, when the switching sleeve is moved from its actual position to its target position, rests against a wall of the groove. After the switching sleeve has been moved from its actual position to its target position, the switching fork is actuated by the actuator in the opposite direction to the direction of actuation specified for the switching operation, preferably such that the switching fork subsequently does not rest against any wall of the groove. In particular, for this purpose, the switching fork is actuated by the actuator by half the groove width of the switching sleeve or by approximately half the groove width in the opposite direction to the direction of actuation specified for the switching operation. This also serves to reduce the risk of wear.

[0009] Preferred embodiments are described in the dependent claims and the following description. Exemplary embodiments of the invention are explained in more detail with reference to the drawing, without being limited thereto. The drawing shows: Fig. 1 A highly schematic representation of a switching element of a motor vehicle to be actuated according to the invention.

[0010] Fig. Figure 1 shows a highly schematic representation of a switching element 10 of a motor vehicle, in particular a transmission, wherein the switching element 10 has a shift sleeve 12 that can be displaced translationally in the direction of the double arrow 11. An actuator 13 serves to displace the shift sleeve 12, which displaces the shift sleeve 11 via a shift rod 14 and a shift fork 15. The actuator 13 can be an electric motor whose rotary motion is converted into a translational motion of the shift rod 14 and shift fork 15. The translational motion of the shift rod 14 and the shift fork 15 is visualized by a double arrow 16.

[0011] A control unit 17 is used to control the actuator 13, which exchanges data with the actuator 13 according to the dashed double arrow 18.

[0012] If the switching sleeve 12 is to be moved from an actual position to a target position for the execution of a circuit, the actuator 13 is energized from the control unit 17 in order to actuate the switching fork 15 in an actuation direction specified for the circuit to be executed and to move the switching sleeve 12 to its target position via the switching fork 15.

[0013] According to the invention, after the switching sleeve 12 has been moved from its actual position to its target position, the switching fork 15 is actuated by the actuator 13 in the opposite direction to the direction of actuation specified for the circuit to be executed, while maintaining the target position of the switching sleeve 12. This is done in such a way that, as a result of the actuation in the opposite direction to the direction of actuation specified for the circuit to be executed, there is subsequently no contact between the switching fork 15 and the switching sleeve 12, so that after the switching sleeve 12 has been moved into its target position, there is no permanent contact between the switching fork 15 and the switching sleeve 12 and therefore no permanent axial contact of the switching fork 15 with the switching sleeve 12 occurs.

[0014] In the exemplary embodiment of the Fig. 1. The switching sleeve 12 has a groove 19 into which the switching fork 15 projects with a section, this section of the switching fork 15 projecting into the groove 19 also being referred to as the switching fork head. To move the switching sleeve 12 from its actual position to the corresponding target position, the section of the switching fork 15 projecting into the groove 19 rests against a wall 19a or 19b of the groove 19. Target in Fig. 1. If the switching fork is moved to the right, the switching fork 15 rests against the wall 19a with the section projecting into the groove 19. If, on the other hand, the switching sleeve 12 is to be moved into Fig. If the section of the shift fork 15 projecting into the groove 19 is moved to the left, it rests against the wall 19b of the groove 19.

[0015] After the switching sleeve 12 has been moved into its target position, the switching fork 15 is actuated by the actuator 13 in the opposite direction to the direction of actuation specified for the circuit to be executed, while maintaining the target position of the switching sleeve 12, such that the section of the switching fork 15 projecting into the groove 19 subsequently does not contact either of the walls 19a, 19b of the groove 19. Specifically, the switching fork 15 is actuated and thus displaced by the actuator 13 by approximately half the width of the groove 19 of the switching sleeve 12 in the opposite direction to the direction of actuation specified for the circuit to be executed, so that the section of the switching fork 15 projecting into the groove 19 is then located approximately in the middle of the groove without contact with either of the walls 19a, 19b.

[0016] The invention further relates to a control unit of a motor vehicle which is configured to automatically execute the above-described method on the control side.

[0017] The control unit 10 therefore controls the actuator 13 by supplying it with an electrical current such that the switching fork 15 is actuated in a direction specified for the circuit to be executed. In doing so, the switching sleeve 12 is moved translationally from its actual position to the respective target position of the circuit to be executed.

[0018] According to the invention, after the switching sleeve 12 has been moved from the actual position to the target position for the circuit to be executed, the control unit 17 controls the actuator 13 in such a way that the switching fork 15 is actuated via the actuator 13 in the opposite direction to the direction of actuation specified for the circuit to be executed, while maintaining the target position of the switching sleeve 12, so that there is subsequently no permanent contact between the switching sleeve 12 and the switching fork 15.

[0019] The control unit 17 according to the invention is preferably an electronic control unit which has hardware and software means for carrying out the method according to the invention. The hardware means include data interfaces for exchanging data with the assemblies involved in carrying out the method according to the invention, for example, with the actuator 13. Furthermore, the hardware means include a processor for data processing and a memory for data storage. The software means include program modules that are implemented in the control unit for carrying out the method according to the invention. Reference sign 10 switching element 11. Relocation of the switching sleeve 12 Switching sleeve 13 Actuator 14 Shift rod 15 shift fork 16. Shift rod relocation, shift fork 17 Control unit 18 Data exchange 19 Nut 19a Wall 19b Wall QUOTES INCLUDED IN THE DESCRIPTION

[0000] This list of documents cited by the applicant was automatically generated and is included solely for the reader's convenience. The list is not part of the German patent or utility model application. The DPMA accepts no liability for any errors or omissions. Cited patent literature

[0000] DE 10 2018 207 590 A1

[0002]

Claims

[1] Method for operating a switching element (10) of a motor vehicle, wherein the switching element (10) has a switching sleeve (12) that can be actuated from an actuator (13) via a switching fork (15), wherein the switching sleeve (12) is translationally moved from an actual position to a target position via the switching fork (15), which is actuated by the actuator (13) in an actuation direction specified for the switching to be performed, in order to execute a switching operation. characterized by , that After the switching sleeve (12) has been moved from the actual position to the target position, the switching fork (15) is actuated via the actuator (13) in the opposite direction to the direction of actuation specified for the switching operation to be performed, while maintaining the target position of the switching sleeve (12). [2] Method according to claim 1, characterized by, that after the switching sleeve (12) has been moved from the actual position to the target position, the switching fork (15) is actuated via the actuator (13) in the opposite direction to the direction of actuation specified for the circuit to be executed, in such a way that as a result of the actuation in the opposite direction to the direction of actuation specified for the circuit to be executed there is no contact between switching fork (15) and switching sleeve (12). [3] Method according to claim 1 or 2, characterized by , that the switching fork (15) engages in a groove (19) in the switching sleeve (12) and then, when the switching sleeve (12) is moved from the actual position to the target position, rests against a wall (19a, 19b) of the groove (19), After the switching sleeve (12) has been moved from the actual position to the target position, the switching fork (15) is actuated via the actuator (13) in the opposite direction to the direction of actuation specified for the switching operation to be performed, such that the switching fork (15) does not rest against any wall (19a, 19b) of the groove (19). [4] Method according to claim 3, characterized by , that after the switching sleeve (12) has been moved from the actual position to the target position, the switching fork (15) is actuated via the actuator (13) by approximately half the groove width of the groove (19) in the switching sleeve (12) in the opposite direction to the direction of actuation specified for the switching operation to be performed. [5] Control unit (17) for operating a switching element (10) of a motor vehicle, wherein the control unit (17) controls an actuator (13) of the switching element (10) in such a way that a switching sleeve (12) of the switching element (10) is translationally moved from an actual position to a target position via a switching fork (15) of the switching element (10), which is actuated by the actuator (17) in an actuation direction specified for the circuit to be executed, characterized by , that The control unit (17), after the switching sleeve (12) has been moved from the actual position to the target position, controls the actuator (13) in such a way that the switching fork (15) is actuated via the actuator (13) in the opposite direction to the direction of actuation specified for the switching operation to be performed, while maintaining the target position of the switching sleeve (12). [6] Control unit according to claim 5, characterized by, that the same is set up to execute the method according to one of claims 1 to 4 automatically on the control side.

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