Methods for wear compensation of clutch discs

Abstract

The present disclosure relates to a method for wear compensation of clutch discs, comprising a compensation value determination process for determining a compensation value for the wear of a clutch disc which is brought into contact and spaced for power transmission and interruption, and a process for applying a compensation value to adjust the clutch disc according to a figure to which the compensation value is applied, wherein the compensation value determination process estimates the wear of the clutch disc and determines the compensation value based on a correlation between the pressure exerted on the clutch disc and the power of an engine exerting the pressure on the clutch disc, thereby preventing a reduction in the transmitted torque due to wear of the clutch disc.

Description

CROSS-REFERENCE TO RELATED REGISTRATION

[0001] This application is based on Korean patent application No. 10-2023-0171623, filed on November 27, 2024, with the Korean Patent Office, the disclosure of which is incorporated in full into this document by reference, and claims its priority under 35 USC §119. BACKGROUND OF THE INVENTION Area of ​​the invention

[0002] The present disclosure relates to a method for wear compensation of clutch discs. Description of the related prior art

[0003] In general, a motor vehicle is driven by transferring power generated by an engine to tires through a power transmission system that includes a transmission, differential gear, and the like.

[0004] Such a motor vehicle can use either a two-wheel drive system, in which only the front or rear wheels are driven, or a four-wheel drive system, in which both the front and rear wheels are driven.

[0005] The four-wheel drive system provides greater driving stability than the two-wheel drive system and is better suited for driving on uneven roads, such as in mountainous terrain, and is divided into a full four-wheel drive system and a selectable two-wheel / four-wheel drive system.

[0006] The selectable two-wheel / four-wheel drive method requires a power transmission system, such as a transfer case, to distribute drive power to the front and rear wheels, and the power transmission system includes clutch discs that come into contact with each other and are spaced apart to transmit and interrupt power.

[0007] Here, the clutch discs include a first clutch disc rotatable with a first shaft and a second clutch disc rotatable with a second shaft, and the first clutch disc and the second clutch disc are pressed against each other and brought into contact or out of contact with each other by a ball ramp, a ball screw or the like, which produces an axial displacement according to the rotation of a motor.

[0008] However, a problem exists in the related prior art in that the transmitted torque is reduced due to wear of the clutch discs. That is, when the first and second clutch discs come into contact and separate, and wear down, their thicknesses decrease over time. And when the engine rotates at a predetermined angle, causing the first and second clutch discs to come into contact, the clamping force between them in the worn state is lower than the clamping force between them in the unworn state.Consequently, the driving force is distributed between the front and rear wheels, contrary to the intended distribution, which leads to problems such as the vehicle no longer being able to drive away from uneven terrain. BRIEF SUMMARY OF THE INVENTION

[0009] It is an objective of the present disclosure to provide a method for wear compensation of clutch discs that is capable of preventing a reduction in transmitted torque due to wear of the clutch discs.

[0010] To accomplish the aforementioned tasks, the disclosed method for clutch disc wear compensation includes a compensation value determination process for determining a compensation value for the wear of a clutch disc that is brought into contact and spaced for power transmission and interruption, and a process for applying a compensation value to adjust the clutch disc according to a figure to which the compensation value is applied, wherein the compensation value determination process includes estimating a wear of the clutch disc and determining a compensation value based on a correlation between the pressure exerted on the clutch disc and the power of an engine exerting the pressure on the clutch disc.

[0011] The compensation value determination process may also include a process for executing a wear compensation control that operates the motor in such a way that it presses the clutch disc and monitors the power and angle of the motor.

[0012] The compensation value determination process may further include a process for determining whether a system condition is met, which determines whether a power transmission system including the clutch disc meets the conditions for executing the process for executing a wear compensation control, and a process for determining whether a vehicle condition is met, which determines whether a vehicle including the power transmission system meets the conditions for executing the process for executing a wear compensation control, wherein the process for executing a wear compensation control can be executed if the process for determining whether a system condition is met determines that the power transmission system meets the conditions, and the process for determining whether a vehicle condition is met determines that the vehicle meets the conditions.

[0013] The process for determining whether a system condition is met may include a first process for determining whether components and input values ​​of the power transmission system are normal, a second process for determining whether a temperature of the power transmission system is within a predetermined temperature range, and a third process for determining whether conditions exist in which wear may have occurred on the clutch disc, wherein the process for determining whether a system condition is met may determine that the power transmission system meets the conditions for executing the process for executing a wear compensation control if the first process for determining whether a system condition is met determines thatthat the components and input values ​​are normal, the second process for determining whether a system condition has been met determines that the temperature is within the predetermined range, and the third process for determining whether a system condition has been met determines that conditions exist in which wear may have occurred on the clutch disc.

[0014] The predetermined temperature range can be set from 20 °C to 90 °C.

[0015] The third process for determining whether a system condition is met can determine that conditions exist in which wear has occurred on the clutch disc if the extent of clutch disc usage or the distance traveled by the vehicle is equal to or greater than a predetermined value.

[0016] The process for determining whether a vehicle condition is met may include a first process for determining whether a vehicle condition is met, which determines whether the vehicle's gear position is in Park or Neutral; a second process for determining whether the vehicle ignition is off; and a third process for determining whether a vehicle CAN input is valid, wherein the process for determining whether a vehicle condition is met may determine that the vehicle meets the conditions for executing the process for executing a wear compensation control if the first process for determining whether a vehicle condition is met determines that the gear position is in Park or Neutral and the second process for determining whether a vehicle condition is met determines that the ignition is off.and the third process for determining whether a vehicle condition has been met determines that the CAN input is valid.

[0017] Assuming that a reference output is defined as the engine power measured when the engine rotates through a reference angle in a situation where no clutch disc wear occurs, the compensation value determination process may further include a data verification process that estimates clutch disc wear and determines a wear compensation value by comparing an engine angle measured during the wear compensation control process with the reference angle when an engine power measured during the wear compensation control process reaches the reference power, or by comparing the engine power measured during the wear compensation control process with the reference power when the engine angle measured during the wear compensation control processthe reference angle is reached, determined.

[0018] The compensation value determination process may further include a state determination process that determines whether at least one of the power transmission system or the vehicle fails to meet the conditions for executing the wear compensation control process, and a wear compensation control interruption process that interrupts a wear compensation control process, wherein, after the wear compensation control process has been executed, the data verification process may be executed if the state determination process determines that the power transmission system and the vehicle meet the conditions, and the wear compensation control interruption process may be executed if the state determination process determines thatthat at least one part of the power transmission system or the vehicle does not meet the conditions.

[0019] The compensation value determination process may further include a data update determination process, which determines whether the existing wear compensation value should be updated with a wear compensation value determined in the data verification process; a data update process, which updates the existing wear compensation value with the wear compensation value determined in the data verification process if it is determined that an update is necessary; and a data retention process, which retains the existing wear compensation value if it is determined that no update is necessary. BRIEF DESCRIPTION OF THE DRAWINGS Fig. Figure 1 is a flowchart illustrating a method for wear compensation of clutch discs according to an embodiment of the present disclosure; Fig. Figure 2 is a flowchart that illustrates in detail a process for estimating the wear degree of the clutch discs and a compensation value in the method for clutch disc wear compensation. Fig. 1 determined; and Fig. 3 is a representation showing the differences between a vehicle on which the clutch disc wear compensation method is applied. Fig. 1 is applied, and illustrates a vehicle to which the procedure is not applied. DETAILED DESCRIPTION OF THE PREFERRED VERSION

[0020] Subsequently, a method for wear compensation of clutch discs according to the present disclosure is described in detail with reference to the attached figures.

[0021] Fig. Figure 1 is a flowchart illustrating a method for wear compensation of clutch discs according to an embodiment of the present disclosure, Fig. Figure 2 is a flowchart that illustrates in detail a process for estimating the wear degree of the clutch discs and a compensation value in the method for clutch disc wear compensation. Fig. 1 determined, and Fig. 3 is a representation showing the differences between a vehicle on which the clutch disc wear compensation method is applied. Fig. 1 is applied, and illustrates a vehicle to which the procedure is not applied.

[0022] With reference to Fig. 1 A method for wear compensation of clutch discs according to an embodiment of the present disclosure may include a process S1 for determining a compensation value for the wear of a clutch disc which is brought into contact and spaced apart for power transmission and interruption, and a process S2 for applying a compensation value for adjusting the clutch disc according to an illustration to which the compensation value is applied.

[0023] Even in a case where it is difficult to provide a sensor capable of measuring pressure exerted on the clutch disc (e.g., when the clutch disc is not controlled by hydraulic pressure but by a mechanism such as a ball ramp or ball screw), the process S1 for determining a compensation value can be configured here to estimate clutch disc wear and determine the compensation value based on a correlation between the pressure exerted on the clutch disc and the power of a motor exerting the pressure on the clutch disc.

[0024] Specifically, process S1 can be used to determine a compensation value with reference to Fig. 2 include a process S14 for executing a wear compensation control that causes the engine to press on the clutch disc and monitors the engine's power and angle.

[0025] Assuming that the engine power measured when the engine rotates at a reference angle in a situation where no clutch disc wear occurs is defined as the reference power, the process S1 for determining a compensation value may further include a process S17 for data verification, which estimates the clutch disc wear and determines a wear compensation value by comparing the engine angle measured in process S14 with the reference angle when the engine power measured in process S14 reaches the reference power, or by comparing the engine power measured in process S14 with the reference power when the engine angle measured in process S14 reaches the reference angle.

[0026] Here, the estimation of a correlation between the engine power and the pressure exerted on the clutch disc can be carried out by a constant speed control of the engine, an engine angle step control, or an engine work control in a disengaged position (a position without clutch reaction force).

[0027] Additionally, the S14 process for executing a wear compensation control can be configured to be executed regardless of the intention of the vehicle's driver in order to improve the accuracy of the wear estimation and the determination of the compensation value for the clutch disc.

[0028] Specifically, process S1 for determining a compensation value may also include process S12 for determining a system condition, which determines whether a power transmission system including the clutch disc meets a condition for executing process S14 for executing a wear compensation control, and process S11 for determining a vehicle state, which determines whether a vehicle including the power transmission system meets a condition for executing process S14, and if process S12 determines that the power transmission system meets the condition for executing process S14, and process S11 determines that the vehicle meets the condition for executing process S14, then process S14 for executing a wear compensation control can be executed.

[0029] In Fig. 2. Process S11 is illustrated as preceding process S12; however, the present disclosure is not limited to this.

[0030] The process S12 for determining a system condition can include a first sub-process for determining a system condition, which determines whether components and input values ​​of the power transmission system are normal; a second sub-process for determining a system condition, which determines whether the temperature of the power transmission system is within a predetermined temperature range; and a third sub-process for determining a system condition, which determines whether a situation has arisen in which wear of the clutch disc may have occurred. If the first sub-process determines that the components and input values ​​of the power transmission system are normal, the second sub-process determines that the temperature of the power transmission system is within the predetermined temperature range (e.g.,20 °C to 90 °C), and in the third sub-process it is determined that a situation has arisen in which clutch disc wear may have occurred (e.g., if clutch disc usage or vehicle mileage exceeds a predetermined value), process S12 for determining a system condition can be configured to determine that the power transmission system meets the condition for executing process S14 for implementing wear compensation control. This may be desirable to improve the accuracy of the determination in process S12. Considering the third sub-process for determining a system condition serves as a reference to prevent unnecessary execution of the determination method.

[0031] The S11 process for determining a vehicle state can include a first sub-process for determining a vehicle state, which determines whether the vehicle is in Park or Neutral, a second sub-process for determining a vehicle state, which determines whether the vehicle ignition is off, and a third sub-process for determining a vehicle state, which determines the validity of the vehicle's CAN inputs. If the first sub-process determines that the vehicle is in Park or Neutral, the second sub-process determines that the vehicle ignition is off, and the third sub-process determines that the vehicle's CAN inputs are valid, the S11 process for determining a vehicle state can be configured to determine that the vehicle meets the condition for executing the S14 process for executing wear compensation control.which may be desirable to improve the accuracy of determining process S11. Considering the third sub-process for determining a vehicle state serves as a reference to prevent misjudgments in the first sub-process for determining a vehicle state, where it might be incorrectly determined that the vehicle is in Park or Neutral, and to prevent misjudgments in the second sub-process for determining a vehicle state, where it might be incorrectly determined that the vehicle ignition is off if there is a fault in the vehicle's CAN input.

[0032] Meanwhile, there may be a case, for example, where the state changes during the execution of process S14 for performing wear compensation control, such as when the vehicle is restarted. To account for this, process S1 for determining a compensation value may also include process S15 for determining a change of state, which determines whether at least one of the power transmission system or the vehicle no longer meets the condition for executing process S14 for performing wear compensation control, and process S16 for interrupting wear compensation control, which interrupts process S14. After the execution of process S14, the following may occur during the execution of the preceding process: Operation S15, if it is determined that the power transmission system and the vehicle meet the condition for performing operation S14, operation S17 for data verification is performed, whereas if operation S15 determines that at least one of the power transmission system or the vehicle does not meet the condition for performing operation S14, operation S16 can be performed.

[0033] As a reference, the unillustrated reference symbol S13 denotes a non-execution operation of the wear compensation control, which is not carried out if, in operation S12 for determining a system condition, it is determined that the power transmission system does not meet the condition for executing operation S14 for executing a wear compensation control, or if, in operation S11 for determining a vehicle condition, it is determined that the vehicle does not meet the condition for executing operation S14.

[0034] Furthermore, to improve the accuracy of clutch disc wear compensation through learning, process S1 for determining a compensation value may also include process S18 for determining the need for a data update, which determines whether the existing wear compensation value should be updated with the wear compensation value determined in process S17 for data verification; process S19 for data update, which updates the existing wear compensation value with the wear compensation value determined in process S17 if process S18 determines that an update is necessary; and process S20 for data storage, which retains the existing wear compensation value if process S18 determines that no update is necessary.

[0035] The method for clutch disc wear compensation according to this configuration can include process S1 for determining a compensation value and process S2 for applying a compensation value, wherein process S1 estimates the wear of the clutch disc and the compensation value is determined based on a correlation between the pressure exerted on the clutch disc and the power of the engine exerting this pressure, thereby preventing a reduction in the transmitted torque due to clutch disc wear, so that, as in Fig. Figure 3 illustrates that even if there is wear on the clutch disc, the driving force is distributed to the front and rear wheels as intended, enabling the vehicle to travel through rough terrain. 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] KR 10-2023-0171623

[0001]

Claims

[1] Method for wear compensation of clutch discs, comprising: a compensation value determination process for determining a compensation value for the wear of a clutch disc that is brought into contact and spaced apart for power transmission and interruption; and a process for applying a compensation value to adjust the clutch disc according to a figure to which the compensation value is applied, wherein the compensation value determination process includes an estimation of wear of the clutch disc and a determination of a compensation value based on a correlation between the pressure exerted on the clutch disc and the power of an engine exerting the pressure on the clutch disc. [2] Method according to claim 1, wherein the compensation value determination process further comprises a process for performing a wear compensation control which operates the motor so that it presses the clutch disc and monitors the power and angle of the motor. [3] Method according to claim 2, wherein the compensation value determination process further comprises: a process for determining whether a system condition has been met, which determines whether a power transmission system including the clutch disc meets the conditions for executing the process for implementing wear compensation control; and a process for determining whether a vehicle condition is met, which determines whether a vehicle incorporating the power transmission system meets the conditions for executing the process for executing a wear compensation control, wherein the process for executing a wear compensation control is carried out when, in the process for determining whether a system condition is met, it is determined that the power transmission system meets the conditions, and in the process for determining whether the vehicle condition is met, it is determined that the vehicle meets the conditions. [4] Method according to claim 3, wherein the process for determining whether a system condition is met comprises: a first process to determine whether a system condition is met, which determines whether components and input values ​​of the power transmission system are normal; a second process for determining whether a system condition is met, which determines whether a temperature of the power transmission system is within a predetermined temperature range; and a third process for determining whether a system condition is met, which determines whether conditions exist under which wear has occurred on the clutch disc, wherein the process for determining the fulfillment of a system condition determines that the power transmission system meets the conditions for executing the process for executing a wear compensation control, if the first process for determining the fulfillment of a system condition determines that the components and input values ​​are normal, the second process for determining the fulfillment of a system condition determines that the temperature is within the predetermined range, and the third process for determining the fulfillment of a system condition determines that conditions are met under which wear has occurred on the clutch disc. [5] Method according to claim 4, wherein the predetermined temperature range is set from 20 °C to 90 °C. [6] Method according to claim 4 or 5, wherein the third step for determining whether a system condition is met determines that conditions exist under which wear has occurred on the clutch disc if the extent of use of the clutch disc or the distance traveled by the vehicle is equal to or greater than a predetermined value. [7] A method according to any of the preceding claims, comprising at least the features of claim 3, wherein the process for determining whether a vehicle condition is met comprises: a first process for determining whether a vehicle condition is met, which determines whether the vehicle's gear position is in park or neutral; a second process for determining whether a vehicle condition is met, which determines whether the vehicle ignition is switched off; and a third process for determining whether a vehicle condition is met, which determines whether a CAN input from the vehicle is valid, wherein the process for determining a vehicle condition fulfillment determines that the vehicle meets the conditions for executing the process for executing a wear compensation control if the first process for determining a vehicle condition fulfillment determines that the gear position is in Park or Neutral, the second process for determining a vehicle condition fulfillment determines that the ignition is off, and the third process for determining a vehicle condition fulfillment determines that the CAN input is valid. [8] A method according to any of the preceding claims, comprising at least the features of claim 3, wherein, assuming that a reference output is defined as an engine power measured when the engine rotates through a reference angle in a situation where no wear occurs on the clutch disc, the compensation value determination process further comprises a data verification process that estimates clutch disc wear and determines a wear compensation value by comparing an engine angle measured in the process for performing a wear compensation control with the reference angle when an engine power measured in the process for performing a wear compensation control reaches the reference power, or by comparing the engine power measured in the process for performing a wear compensation control with the reference power.when the motor angle, measured during the process of executing a wear compensation control, reaches the reference angle. [9] Method according to claim 8, wherein the compensation value determination process further comprises: a process for determining a change of state, which determines whether at least one of the power transmission system or the vehicle fails to meet the conditions for executing the process for executing a wear compensation control; and a process for interrupting a wear compensation control, which interrupts the process for executing a wear compensation control, wherein, after the execution of the process to execute a wear compensation control, the process to verify the data is executed if the process to determine a change of state determines that the power transmission system and the vehicle meet the conditions, and the process to interrupt a wear compensation control is executed if the process to determine a change of state determines that at least one of the power transmission system or the vehicle does not meet the conditions. [10] Method according to claim 8 or 9, wherein the compensation value determination process further comprises: a process for determining the need for a data update, which determines whether the existing wear compensation value should be updated with a wear compensation value determined in the data verification process; a data update process that updates the existing wear compensation value with the wear compensation value determined in the data verification process when it is determined that an update is necessary; and a data retention process that maintains the existing wear compensation value when it is determined that no update is necessary.

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