Control method of control system of lock-up clutch, transmission controller, and vehicle

Abstract

The application provides a control method of a control system of a lock clutch, a gearbox controller and a vehicle. The method comprises the following steps: judging whether a control system of a lock clutch of a hydraulic torque converter satisfies a preset self-cleaning activation condition; and when the condition is satisfied, controlling a pressure regulating assembly according to a preset self-cleaning control strategy; controlling the lock clutch to be re-locked, judging whether the re-locking is successful; if the re-locking is not successful, performing self-cleaning again until the number of times of re-locking of the lock clutch reaches a preset number of times. Then, fault information is output to a vehicle control unit, and the vehicle control unit generates and sends alarm information according to the fault information. When the lock clutch cannot be normally locked, the corresponding self-cleaning strategy is executed, so that the problem that the lock clutch cannot be normally locked due to accidental jamming can be eliminated, and the driving safety is improved. Moreover, the fault does not need to be reported to the vehicle control unit, the driver does not need to be prompted to perform maintenance, and the driving experience is improved.

Description

Technical Field

[0001] This invention relates to the field of vehicle transmission system control technology, and in particular to a control method for a hydraulic torque converter lock-up clutch control system, a transmission controller, and a vehicle. Background Technology

[0002] The torque converter is installed between the engine and the transmission, using hydraulic oil as its working medium. It functions to transmit torque, change torque, change speed, and engage / disengage the clutch. When the vehicle is traveling at low speeds, the torque converter improves the smoothness of starting through hydraulic transmission. When the vehicle is traveling at high speeds, mechanical transmission is achieved through the locking of the torque converter's lock-up clutch, improving transmission efficiency and fuel economy.

[0003] The lock-up clutch of a hydraulic torque converter has two states: locked and disengaged. For example... Figure 1 As shown, the state of the lock-up clutch 5 is controlled by the solenoid valve 1 and the pressure regulating spool valve 2. Controlling the output pressure of the solenoid valve 1 controls the position of the valve core of the pressure regulating spool valve 2. Movement of the valve core enables the reversal and pressure regulation of the oil circuit, thereby locking and disengaging the lock-up clutch 5. Specifically, a lock-up oil circuit and a disengagement oil circuit are provided between the output end of the pressure regulating spool valve 2 and the torque converter. When the oil pressure in the lock-up oil circuit 3 is greater than the oil pressure in the disengagement oil circuit 4, the lock-up clutch 5 locks up; when the oil pressure in the disengagement oil circuit 4 is greater than the oil pressure in the lock-up oil circuit 3, the lock-up clutch 5 disengages.

[0004] However, during use, transmissions are prone to generating debris due to hardware wear and tear. This debris dissolves into the hydraulic fluid, causing the hydraulic system or transmission hardware to become stuck, which in turn prevents the torque converter's lock-up clutch from engaging, thus affecting driving safety. Furthermore, vehicles typically display a fault code immediately when the lock-up clutch fails to engage, which also impacts the driving experience for passengers. Summary of the Invention

[0005] The purpose of this invention is to solve the problems in the prior art where debris from the transmission can cause the hydraulic system or transmission hardware to jam, affecting driving safety, and the immediate reporting of a fault code when the lock-up clutch fails to lock, which affects the driving experience of the occupants.

[0006] To address the aforementioned problems, embodiments of the present invention disclose a control method for a lock-up clutch control system of a hydraulic torque converter. The control system for the lock-up clutch of the hydraulic torque converter includes: a pressure regulating component, a lock-up oil circuit, and a disengagement oil circuit; wherein, the pressure regulating component is connected to the transmission controller, and the transmission controller is also connected to the vehicle controller; the input ends of the lock-up oil circuit and the disengagement oil circuit are both connected to the pressure regulating component, and the output ends are connected to the lock-up clutch of the hydraulic torque converter. The pressure regulating component adjusts the pressure of the oil flowing through the lock-up oil circuit and the disengagement oil circuit according to the control signal from the transmission controller to control the locking and / or disengagement of the lock-up clutch.

[0007] Control methods include:

[0008] S1: The transmission controller obtains vehicle status information from the vehicle controller and determines whether the lock-up clutch control system meets the preset self-cleaning activation conditions based on the vehicle status information and the fault information of the transmission controller.

[0009] If so, proceed to step S2;

[0010] If not, continue to determine whether the control system of the lock-up clutch simultaneously meets all the preset self-cleaning activation conditions;

[0011] S2: The transmission controller controls the pressure regulating components using a preset self-cleaning control strategy;

[0012] S3: The transmission controller controls the lock-up clutch to relock and determines whether the relocking is successful based on the relationship between the sliding friction work of the lock-up clutch and the preset sliding friction work threshold.

[0013] If successful, control is terminated;

[0014] If unsuccessful, repeat steps S2 and S3 until the lock-up clutch relocks a preset number of times, and then execute step S4.

[0015] S4: The transmission controller outputs a fault message that the lock-up clutch cannot lock properly to the vehicle controller. The vehicle controller generates and sends an alarm message based on the fault message.

[0016] By employing the above solution, when the lock-up clutch fails to lock properly, the corresponding self-cleaning strategy can eliminate the problem of occasional jamming causing the lock-up clutch to fail to lock properly, thus improving driving safety. Furthermore, it eliminates the need to report a fault to the vehicle controller or prompt the driver for repairs, improving the driving experience. In addition, this solution attempts to lock the lock-up clutch after one self-cleaning cycle. If it still fails to lock, it attempts self-cleaning again instead of immediately reporting a fault. This avoids the problem of a system jam being mistaken for a lock-up clutch failure due to inadequate self-cleaning, leading to an immediate fault report and impacting the driving experience. If the lock-up clutch still fails to lock properly after several self-cleaning cycles, it indicates that the abnormal lock-up clutch is not caused by system jamming. At this point, a fault report is issued to remind the driver to repair the clutch, ensuring vehicle safety. Repair personnel also do not need to further investigate whether the lock-up abnormality is caused by system jamming during repairs, saving repair time and reducing repair costs.

[0017] According to another specific embodiment of the present invention, the control method for the control system of the lock-up clutch of the hydraulic torque converter disclosed in this embodiment includes, in step S1, vehicle status information including: engine speed, transmission oil temperature, throttle opening, target lock-up capacity of the hydraulic torque converter, engine torque, turbine speed, and slip friction work of the lock-up clutch; and preset self-cleaning activation conditions including: no fault codes inside the transmission controller; engine speed higher than a preset speed threshold; transmission oil temperature within a preset temperature range; throttle opening greater than a preset opening threshold; target lock-up capacity of the hydraulic torque converter higher than a preset difference in engine torque for more than a preset time; speed difference between engine speed and turbine speed greater than a preset speed difference threshold; and slip friction work of the lock-up clutch greater than a preset slip friction work threshold.

[0018] By employing the above scheme, the self-cleaning strategy is executed only after no fault codes are found within the transmission controller, thus avoiding the execution of ineffective self-cleaning strategies. Furthermore, using an engine speed exceeding a preset threshold as the activation condition for self-cleaning ensures sufficient flow in the hydraulic system. Using a transmission oil temperature within a preset range as the activation condition prevents the self-cleaning strategy from being activated when it is not needed, improving system efficiency and reducing operating costs. Using throttle opening exceeding a preset threshold, the target lock-up capacity of the torque converter exceeding a preset difference in engine torque for a preset time, and the speed difference between engine speed and turbine speed exceeding a preset speed difference threshold as activation conditions for self-cleaning improves the effectiveness of self-cleaning and the accuracy of locking-up clutch anomaly detection.

[0019] According to another specific embodiment of the present invention, the control method for the lock-up clutch control system of the hydraulic torque converter disclosed in this embodiment of the present invention has the following preset values: a speed threshold range of 1200 rpm to 1400 rpm; a temperature range of 20°C to 110°C; an opening threshold range of 5% to 15%; a time range of 300ms to 600ms; a preset difference value of 0.5 to 1 times the engine torque; a preset speed difference threshold of 100 rpm to 200 rpm; and a preset slip friction work threshold of 60% to 80% of the work corresponding to the hardware protection pressure threshold of the hydraulic torque converter.

[0020] According to another specific embodiment of the present invention, in the control method of the control system of the lock-up clutch of the hydraulic torque converter disclosed in this embodiment, the preset self-cleaning control strategy in step S2 includes: outputting a pulse corresponding to the target lock-up capacity of the hydraulic torque converter to the pressure regulating component until the number of pulses output to the pressure regulating component reaches a preset number of pulses; wherein, the pulse corresponding to the target lock-up capacity of the hydraulic torque converter is a rectangular wave; the amplitude of the pulse is determined according to the transmission oil temperature and the hardware protection pressure threshold of the hydraulic torque converter; the period of the pulse is determined according to the transmission oil temperature.

[0021] According to another specific embodiment of the present invention, the control method of the control system of the lock-up clutch of the hydraulic torque converter disclosed in the present invention has a pulse period in the range of 20ms to 50ms; a pulse amplitude in the range of 5bar to 8bar; a preset number of pulses of 4 to 6 times; and in step S3, the preset number of pulses is in the range of 2 to 4 times.

[0022] By adopting the above solution and setting the preset number of times to 2 to 4, the problem of failure of self-cleaning on the first attempt can be avoided, as well as the problem of long time and reduced system efficiency due to multiple attempts.

[0023] According to another specific embodiment of the present invention, in the control method of the lock-up clutch control system of the hydraulic torque converter disclosed in this embodiment, in step S4, the vehicle controller generates and sends alarm information based on fault information, including: the vehicle controller generates and sends alarm information to the vehicle instrument panel to illuminate the exhaust lights; and sends alarm information to the engine controller to limit the output torque of the engine within a preset torque range; wherein the preset torque range is 100 N·m to 200 N·m.

[0024] Using the above solution, if the lock-up clutch fails to lock properly after self-cleaning, the vehicle controller generates and sends an alarm message to the vehicle's instrument panel based on the fault information, illuminating the exhaust lights to remind the driver to have it repaired promptly. Sending the alarm message to the engine controller to limit engine output torque can restrict vehicle speed and acceleration, reducing the danger caused by lock-up clutch malfunction.

[0025] According to another specific embodiment of the present invention, the control method of the control system of the lock-up clutch of the hydraulic torque converter disclosed in this embodiment includes a pressure regulating component comprising: a solenoid valve, the input end of which is connected to the transmission controller and receives a control signal from the transmission controller; and a pressure regulating spool valve, the input end of which is connected to the output end of the solenoid valve via a control oil circuit, and the output end of which is connected to the input end of the separation oil circuit and the input end of the lock-up oil circuit, respectively.

[0026] According to another specific embodiment of the present invention, in the control method of the control system of the lock-up clutch of the hydraulic torque converter disclosed in this embodiment of the present invention, when the transmission controller outputs fault information, step S4 further includes: outputting the oil pressure information of the lock-up oil circuit to the vehicle controller; wherein, the oil pressure information of the lock-up oil circuit includes the oil pressure of the lock-up oil circuit and the oil pressure change rate of the lock-up oil circuit; and, the vehicle controller generates and sends alarm information according to the fault information, further including: determining whether the oil pressure of the lock-up oil circuit is lower than a preset oil pressure threshold and whether the oil pressure change rate of the lock-up oil circuit is greater than a preset change rate threshold;

[0027] If not, the exhaust lights will remain on and the engine's output torque will be limited to the range of 150 N·m to 200 N·m.

[0028] If so, the exhaust light will remain on and the engine's output torque will be limited to the range of 100 N·m to 150 N·m.

[0029] By employing the above-mentioned solution, the severity of the lock-up clutch malfunction is assessed based on the oil pressure and its rate of change in the lock-up oil circuit. This improves the accuracy of determining the severity of the lock-up clutch control system malfunction, preventing misjudgments that could limit engine output torque and reduce the driving experience. Furthermore, when the lock-up clutch control system malfunction is severe, keeping the exhaust light constantly illuminated and limiting engine output torque to a lower range serves as a reminder to the driver to request prompt repair. It also allows for control of vehicle speed and acceleration, enhancing driving safety.

[0030] Embodiments of the present invention also disclose a transmission controller, comprising: a memory for storing a control program; and a processor, wherein the processor, when processing the control program, executes the steps of the control method for the control system of the lock-up clutch of the hydraulic torque converter as described in any of the above embodiments.

[0031] Embodiments of the present invention also disclose a vehicle including a transmission controller as described in the above embodiments.

[0032] The beneficial effects of this invention are:

[0033] This solution, when the lock-up clutch fails to lock properly, further determines whether the self-cleaning conditions are met. If the self-cleaning conditions are met, the pressure regulating component is controlled and self-cleaned to attempt to eliminate the fault. After self-cleaning, the lock-up clutch is attempted to lock again. If locking is still unsuccessful, self-cleaning continues. After a certain number of self-cleaning cycles, if the lock-up clutch still fails to lock properly, a fault message is generated in the transmission controller, and the transmission controller generates an alarm message based on this fault message to alert the driver of the lock-up clutch malfunction requiring maintenance. This approach addresses the issue that occasional lock-up clutch malfunctions may be caused by sticking within the torque converter system. Self-cleaning can resolve the problem of the lock-up clutch failing to lock properly due to sticking. Therefore, this solution, by executing the corresponding self-cleaning strategy when the lock-up clutch fails to lock properly, can eliminate the problem of occasional sticking causing the lock-up clutch to fail to lock properly, improving driving safety. Furthermore, it eliminates the need to report a fault to the vehicle controller or prompt the driver for maintenance, thus improving the driving experience. Furthermore, this solution attempts to lock the lock-up clutch after one self-cleaning cycle. If it still fails to lock, it re-attempts self-cleaning instead of immediately reporting a fault. This avoids the problem of a system malfunction being mistaken for an inadequate self-cleaning process, leading to an immediate fault report and impacting the driving experience. If the lock-up clutch still fails to lock after several self-cleaning cycles, it indicates that the lock-up clutch malfunction is not caused by a system malfunction. At this point, a fault report is issued to remind the driver to have it repaired. This ensures vehicle safety, and repair personnel do not need to further investigate whether the malfunction is caused by a system malfunction, saving repair time and reducing repair costs. Attached Figure Description

[0034] Figure 1 This is a schematic diagram of the control system of the lock-up clutch in a hydraulic torque converter in the prior art;

[0035] Figure 2 This is a schematic diagram of the control system for the lock-up clutch of the hydraulic torque converter provided in an embodiment of the present invention;

[0036] Figure 3 This is a flowchart of the control method for the lock-up clutch control system of the hydraulic torque converter provided in an embodiment of the present invention;

[0037] Figure 4This is a schematic diagram of the curves when the self-cleaning control strategy is executed according to an embodiment of the present invention;

[0038] Figure 5 This is a schematic diagram of the curve when the device is normally locked after self-cleaning, as provided in an embodiment of the present invention.

[0039] Figure 6 This is a schematic diagram of the curve when the self-cleaning process fails to lock properly, as provided in the embodiment of the present invention.

[0040] Explanation of reference numerals in the attached figures:

[0041] 1. Solenoid valve; 2. Pressure regulating slide valve; 3. Lock-up oil circuit; 4. Separation oil circuit; 5. Lock-up clutch; 6. Transmission controller; 7. Vehicle controller; 8. Control oil circuit. Detailed Implementation

[0042] The following specific embodiments illustrate the implementation of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. Although the description of the present invention is presented in conjunction with preferred embodiments, this does not mean that the features of the invention are limited to these embodiments. On the contrary, the purpose of describing the invention in conjunction with embodiments is to cover other options or modifications that may be derived based on the claims of the present invention. To provide a deep understanding of the invention, many specific details will be included in the following description. The invention may also be implemented without using these details. Furthermore, to avoid confusion or obscuring the focus of the invention, some specific details will be omitted in the description. It should be noted that, unless otherwise specified, the embodiments and features in the embodiments of the present invention can be combined with each other.

[0043] It should be noted that in this specification, similar reference numerals and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0044] In the description of this embodiment, it should also be noted that, unless otherwise explicitly specified and limited, the terms "set up," "connected," and "linked" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this embodiment based on the specific circumstances.

[0045] To make the objectives, technical solutions, and advantages of the present invention clearer, the embodiments of the present invention will be described in further detail below with reference to the accompanying drawings.

[0046] Example 1:

[0047] To address the problems in existing technologies where gearbox debris can cause jamming in the hydraulic system or gearbox hardware, affecting driving safety, and where the immediate reporting of a fault code when the lock-up clutch fails to lock up can negatively impact the driving experience for passengers, embodiments of the present invention provide a control method for the control system of the lock-up clutch of a hydraulic torque converter.

[0048] Specifically, such as Figure 2 As shown, the control system of the lock-up clutch 5 of the torque converter includes a pressure regulating assembly, which includes a solenoid valve 1 and a pressure regulating spool valve 2. The control system of the lock-up clutch 5 of the torque converter also includes a lock-up oil passage 3 and a disengagement oil passage 4. The pressure regulating assembly is connected to the transmission controller 6, which is also connected to the vehicle controller 7. The input ends of both the lock-up oil passage 3 and the disengagement oil passage 4 are connected to the pressure regulating assembly, and their output ends are connected to the lock-up clutch 5 of the torque converter. The pressure regulating assembly adjusts the pressure of the oil flowing through the lock-up oil passage 3 and the disengagement oil passage 4 according to the control signal from the transmission controller 6 to control the locking and / or disengagement of the lock-up clutch 5.

[0049] Furthermore, in the control method of the lock-up clutch control system of the hydraulic torque converter according to the present invention, reference is made to... Figure 2 The input terminal of the solenoid valve 1 of the pressure regulating assembly is connected to the transmission controller 6, receiving control signals from the transmission controller 6. The input terminal of the pressure regulating spool valve 2 is connected to the output terminal of the solenoid valve 1 via the control oil circuit 8. The output terminal of the pressure regulating spool valve 2 is connected to the input terminal of the separation oil circuit 4 and the input terminal of the lock-up oil circuit 3, respectively. Specifically, the transmission controller 6 transmits the adjustment signal to the solenoid valve 1. The solenoid valve 1 adjusts its valve core position to regulate the oil pressure and flow rate of the control oil circuit 8, thereby changing the pressure at both ends of the pressure regulating spool valve 2. This causes a change in the valve core position of the pressure regulating spool valve 2, which in turn changes the oil pressure in the lock-up oil circuit 3 and the separation oil circuit 4 connected to the pressure regulating spool valve 2. When the oil pressure in the lock-up oil circuit 3 is greater than the oil pressure in the separation oil circuit 4, the lock-up clutch 5 locks up; when the oil pressure in the separation oil circuit 4 is greater than the oil pressure in the lock-up oil circuit 3, the lock-up clutch 5 disengages.

[0050] Furthermore, in the control method of the lock-up clutch control system of the hydraulic torque converter according to the present invention, such as Figure 3 As shown, the control methods include:

[0051] S1: The transmission controller obtains vehicle status information from the vehicle controller and determines whether the lock-up clutch control system meets the preset self-cleaning activation conditions based on the vehicle status information and the fault information of the transmission controller.

[0052] If so, proceed to step S2;

[0053] If not, continue to determine whether the control system of the lock-up clutch simultaneously meets all the preset self-cleaning activation conditions;

[0054] S2: The transmission controller controls the pressure regulating components using a preset self-cleaning control strategy;

[0055] S3: The transmission controller controls the lock-up clutch to relock and determines whether the relocking is successful based on the relationship between the sliding friction work of the lock-up clutch and the preset sliding friction work threshold.

[0056] If successful, control is terminated;

[0057] If unsuccessful, repeat steps S2 and S3 until the lock-up clutch relocks a preset number of times, and then execute step S4.

[0058] S4: The transmission controller outputs a fault message that the lock-up clutch cannot lock properly to the vehicle controller. The vehicle controller generates and sends an alarm message based on the fault message.

[0059] Specifically, in step S1, the transmission controller and the vehicle controller communicate wirelessly, interacting with each other to obtain vehicle status information. In this embodiment, the vehicle status information refers to parameters of the vehicle's powertrain related to the lock-up or engagement state of the lock-up clutch. This information can be measured by sensors or other measuring components distributed throughout the vehicle's powertrain and transmitted to the vehicle controller. The transmission controller's fault information refers to information received by the transmission controller regarding hardware or hydraulic system malfunctions within the transmission. When a hardware or hydraulic system malfunctions within the transmission, a fault code is sent to the transmission controller; this fault code constitutes the fault information.

[0060] More specifically, in step S3, the method for controlling the re-locking of the lock-up clutch is still to control the pressure of the oil in the lock-up oil circuit and the separation oil circuit by controlling the pressure regulating component. Furthermore, in this embodiment, if the slip friction work of the lock-up clutch is greater than a preset slip friction work threshold, it is determined that the re-locking of the lock-up clutch is unsuccessful; if the slip friction work of the lock-up clutch is less than or equal to the preset slip friction work threshold, it is determined that the re-locking of the lock-up clutch is successful. Here, slip friction work refers to the slip friction power of the lock-up clutch during the locking process.

[0061] It should be noted that the control method provided in this embodiment is executed when the lock-up clutch experiences a lock-up abnormality. Therefore, before step S1, there is a step to determine whether the lock-up clutch has experienced a lock-up abnormality. Since a lock-up clutch malfunction can cause problems such as insignificant overspeed in overdrive, vibration or noise from the lock-up clutch, and high temperatures in the torque converter when the lock-up clutch slips, or the torque converter lock-up clutch failing to disengage, leading to engine stalling during emergency braking, the presence of a lock-up abnormality can be determined by factors such as vehicle speed, noise, torque converter temperature, and engine status.

[0062] In this embodiment, when the lock-up clutch fails to lock properly, it further determines whether the self-cleaning conditions are met. If the self-cleaning conditions are met, the pressure regulating component is controlled and self-cleaned to attempt to eliminate the fault. After self-cleaning is completed, the lock-up clutch is attempted to lock again. If locking is still unsuccessful, self-cleaning continues. After a certain number of self-cleaning cycles, if the lock-up clutch still fails to lock properly, a fault message is generated in the transmission controller, and the transmission controller generates an alarm message based on this fault message to alert the driver that the lock-up clutch is faulty and requires repair. This approach addresses the issue that occasional lock-up clutch failures may be caused by sticking within the torque converter system. Self-cleaning can resolve the problem of the lock-up clutch failing to lock properly due to sticking. Therefore, this solution executes a corresponding self-cleaning strategy when the lock-up clutch fails to lock properly, eliminating the problem of occasional sticking and improving driving safety. Furthermore, it eliminates the need to report a fault to the vehicle controller or prompt the driver for repair, thus improving the driving experience. Furthermore, this solution attempts to lock the lock-up clutch after one self-cleaning cycle. If it still fails to lock, it re-attempts self-cleaning instead of immediately reporting a fault. This avoids the problem of a system malfunction being mistaken for an inadequate self-cleaning process, leading to an immediate fault report and impacting the driving experience. If the lock-up clutch still fails to lock after several self-cleaning cycles, it indicates that the lock-up clutch malfunction is not caused by a system malfunction. At this point, a fault report is issued to remind the driver to have it repaired. This ensures vehicle safety, and repair personnel do not need to further investigate whether the malfunction is caused by a system malfunction, saving repair time and reducing repair costs.

[0063] Furthermore, in the control method of the lock-up clutch control system of the hydraulic torque converter according to the present invention, in step S1, the vehicle state information includes: engine speed, transmission oil temperature, throttle opening, target lock-up capacity of the hydraulic torque converter, engine torque, turbine speed, and slip friction work of the lock-up clutch. Specifically, the engine speed can be measured by a signal disc and speed sensor mounted on the engine crankshaft; the transmission oil temperature is measured by an oil temperature sensor installed in the transmission; the throttle opening is determined by a throttle pedal position sensor; the target lock-up capacity of the hydraulic torque converter refers to the target lock-up capacity value output by the lock-up capacity control device of the hydraulic torque converter, which is not fundamentally different from the lock-up capacity control device in the prior art; the engine torque is calculated by the engine controller based on the measurement result of the lever arm and the design dimensions of the crankshaft; the turbine speed can be measured by an existing turbine speed measuring device; and the slip friction work of the lock-up clutch is calculated by parameters such as the rotational inertia of the engine and the clutch driving part, the rotational inertia of the driven part, the clutch engagement time, the engine output torque, and the engine output speed, and the calculation method can refer to the prior art.

[0064] Furthermore, in the control method of the lock-up clutch control system of the hydraulic torque converter according to the present invention, the preset self-cleaning activation conditions include: no fault codes inside the transmission controller; engine speed higher than a preset speed threshold, wherein the preset speed threshold ranges from 1200 rpm to 1400 rpm, for example 1200 rpm, 1300 rpm, 1400 rpm, or other values ​​within this range; transmission oil temperature within a preset temperature range, wherein the preset temperature range is from 20°C to 110°C, for example 20°C, 55°C, 100°C, 110°C, or other values ​​within this range; and throttle opening greater than a preset opening threshold, wherein the preset opening threshold ranges from 5% to 15%. For example, it could be 5%, 10%, 15%, or other values ​​within that range; the target lock-up capacity of the torque converter is higher than the preset difference in engine torque and exceeds a preset time, where the preset difference is 0.5 to 1 times the engine torque, that is, the target lock-up capacity of the torque converter is 1.5 to 2 times the engine torque; the preset time ranges from 300ms to 600ms, for example, it could be 300ms, 450ms, 600ms, or other values ​​within that range; the speed difference between the engine speed and the turbine speed is greater than a preset value. The speed difference threshold is set, wherein the preset speed difference threshold is 100rpm to 200rpm, for example, it can be 100rpm, 150rpm, 200rpm, or other values ​​within this range; and the slip friction work of the lock-up clutch is greater than the preset slip friction work threshold, wherein the preset slip friction work threshold is 60% to 80% of the work corresponding to the hardware protection pressure threshold of the hydraulic torque converter, and the hardware protection pressure threshold is the maximum value of the hydraulic pressure that does not cause damage to the hardware of the hydraulic torque converter, which is determined comprehensively based on the characteristics of the hardware, oil temperature and other parameters.

[0065] Specifically, setting the absence of fault codes within the transmission controller as the activation condition for self-cleaning is to avoid the influence of existing faults on the self-cleaning strategy and to prevent misjudgments. In other words, if the lock-up clutch's abnormal locking is caused by a hardware fault, and this hardware fault has been detected and a fault code has been sent to the transmission controller, then executing the self-cleaning strategy will not restore normal lock-up of the lock-up clutch. Therefore, executing the self-cleaning strategy after the absence of fault codes within the transmission controller can prevent the execution of an ineffective self-cleaning strategy.

[0066] Setting the engine speed range of 1200 rpm to 1400 rpm as the activation condition for self-cleaning is to ensure sufficient flow in the hydraulic system. Sufficient hydraulic system flow improves the effectiveness of self-cleaning and further avoids misjudging lock-up abnormalities caused by insufficient hydraulic system flow.

[0067] When the transmission fluid temperature is low, the torque converter itself does not lock up, so there is no need to activate the self-cleaning strategy. Conversely, when the transmission fluid temperature is too high, the transmission is in an abnormal operating state, and there is no need for the self-cleaning strategy in this case either. Therefore, using a transmission fluid temperature range of 20°C to 110°C as the activation condition for self-cleaning can avoid activating the self-cleaning strategy when it is not necessary, thereby improving system operating efficiency and reducing operating costs.

[0068] Setting the throttle opening to be greater than 5% to 15% as the activation condition for self-cleaning is to ensure that the self-cleaning strategy is executed under the condition of positive power output; otherwise, the effectiveness of self-cleaning will be affected.

[0069] Under normal circumstances, when the target lock-up capacity of the torque converter is close to the engine torque, the lock-up clutch of the torque converter should engage. However, if the target lock-up capacity of the torque converter exceeds a certain threshold of the engine torque, such as 1.5 to 2 times the engine torque, and this exceeds the threshold for a certain period of time, such as 300ms to 600ms, it indicates that the lock-up is abnormal. Therefore, using the difference between the target lock-up capacity of the torque converter and the engine torque for a preset time as the activation condition for self-cleaning can improve the accuracy of lock-up clutch abnormality detection and also fully consider the response time of the hydraulic system.

[0070] Under normal circumstances, when the target lock-up capacity of the torque converter is close to the engine torque, the lock-up clutch of the torque converter should engage, and the speed difference between the engine speed and the turbine speed should be eliminated. However, if the target lock-up capacity of the torque converter is higher than a certain threshold of engine torque, and the speed difference remains large after a certain period of confirmation, it indicates that the lock-up performance is abnormal. Therefore, using a speed difference greater than a preset threshold between engine speed and turbine speed as the activation condition for self-cleaning can improve the accuracy of lock-up clutch fault diagnosis.

[0071] Setting the slip friction of the lock-up clutch to exceed a preset slip friction threshold as the activation condition for self-cleaning is to activate the protection function before the slip friction exceeds the hardware protection pressure threshold, thus avoiding direct fault reporting and affecting the driving experience.

[0072] Furthermore, in the control method of the lock-up clutch control system of the hydraulic torque converter according to the present invention, in step S2, the preset self-cleaning control strategy includes: outputting pulses corresponding to the target lock-up capacity of the hydraulic torque converter to the pressure regulating component until the number of pulses output to the pressure regulating component reaches a preset number of pulses.

[0073] Specifically, the pulse corresponding to the target lock-up capacity of the hydraulic torque converter is a rectangular wave; the amplitude of the pulse is determined based on the transmission oil temperature and the hardware protection pressure threshold of the hydraulic torque converter; the period of the pulse is determined based on the transmission oil temperature.

[0074] Furthermore, in the control method of the lock-up clutch control system of the hydraulic torque converter according to the present invention, the pulse period is in the range of 20ms to 50ms, for example, 20ms, 30ms, 50ms, or other values ​​within this range; the pulse amplitude is in the range of 5bar to 8bar, for example, 5bar, 6.5bar, 8bar, or other values ​​within this range; the preset number of pulses is 4 to 6 times, for example, 4 times, 5 times, or 6 times.

[0075] It should be noted that the amplitude of the pulses can be increased sequentially to achieve a better self-cleaning effect.

[0076] It should also be noted that the pulse period cannot be set too short, otherwise the solenoid valve controlling the lock-up clutch will not be able to generate sufficient pressure at the current oil temperature. Furthermore, the pulse period cannot be set too short either, otherwise the pressure generated by the solenoid valve will be too high, causing impact on the lock-up clutch. The interval between pulses needs to ensure that the pressure generated within the pulse generation cycle has been fully released; otherwise, the self-cleaning effect will be affected. However, this interval cannot be too short, otherwise the pressure generated within the pulse generation cycle will not be fully released, affecting the self-cleaning effect; nor should it be too long, otherwise it will prolong the self-cleaning time and reduce the self-cleaning efficiency. A typical interval of 30ms to 60ms achieves a good balance between pressure release completion and self-cleaning efficiency.

[0077] Furthermore, in the control method of the lock-up clutch control system of the hydraulic torque converter according to the present invention, in step S3, the preset number of attempts ranges from 2 to 4 times, for example, 2, 3, or 4 times. That is, if the first self-cleaning attempt fails, a second attempt is made. If, for example, after the fourth self-cleaning attempt, the lock-up clutch still cannot lock properly, a fault message is output. Setting the preset number of attempts to 2 to 4 times is to avoid the problem of failure on the first attempt and to avoid the problem of excessive attempts taking too long and reducing system efficiency.

[0078] Furthermore, in the control method of the lock-up clutch control system of the hydraulic torque converter according to the present invention, in step S4, the vehicle controller generates and sends alarm information based on fault information, including: the vehicle controller generates and sends alarm information to the vehicle instrument panel to illuminate the exhaust lights; and sends alarm information to the engine controller to limit the engine output torque within a preset torque range. The preset torque range is 100 N·m to 200 N·m. In this manner, when the lock-up clutch fails to lock properly after self-cleaning, the vehicle controller generates and sends alarm information to the vehicle instrument panel to illuminate the exhaust lights, thereby reminding the driver to perform timely maintenance. Sending alarm information to the engine controller to limit the engine output torque can limit the vehicle speed and acceleration, reducing the danger caused by lock-up clutch failure. Furthermore, a torque range of 100 N·m to 200 N·m will not cause engine overheating, improving the stability of system operation.

[0079] Furthermore, in the control method of the lock-up clutch control system of the hydraulic torque converter according to the present invention, when the transmission controller outputs fault information in step S4, it further includes: outputting the oil pressure information of the lock-up oil circuit to the vehicle controller. The oil pressure information of the lock-up oil circuit includes the oil pressure of the lock-up oil circuit and the oil pressure change rate of the lock-up oil circuit. Specifically, the oil pressure of the lock-up oil circuit is measured by a pressure sensor installed in the oil circuit, and the oil pressure change rate is calculated based on the collected oil pressure.

[0080] Furthermore, in the control method of the lock-up clutch control system of the hydraulic torque converter according to the present invention, the vehicle controller generates and sends alarm information based on fault information, and further includes:

[0081] Determine whether the oil pressure in the lock-up oil circuit is lower than the preset oil pressure threshold and whether the oil pressure change rate in the lock-up oil circuit is greater than the preset change rate threshold.

[0082] If not, the exhaust lights will remain on and the engine's output torque will be limited to the range of 150 N·m to 200 N·m.

[0083] If so, the exhaust light will remain on and the engine's output torque will be limited to the range of 100 N·m to 150 N·m.

[0084] Specifically, the preset oil pressure threshold range is 100kPa to 300kPa, determined by the size of the solenoid valve outlet; a larger outlet results in higher oil pressure, and a smaller outlet results in lower oil pressure. The oil pressure change rate is 50kPa / min to 80kPa / min. A higher change rate indicates more unstable oil pressure, making it easier to impact the lock-up clutch and indicating a more serious malfunction in the lock-up clutch control system. Normal lock-up oil circuit pressure is between 150kPa and 500kPa. If it is below 100kPa to 300kPa, it indicates excessively low lock-up oil circuit pressure, suggesting a more serious malfunction in the lock-up clutch control system. In this case, the exhaust light remains constantly illuminated, and the engine output torque is limited to a lower range. This serves as a reminder to the driver to have it repaired promptly and also allows for control of vehicle speed and acceleration, improving driving safety. Furthermore, the influence of the lock-up oil circuit pressure change rate is considered, improving the accuracy of judging the severity of lock-up clutch control system malfunctions and avoiding the limitation of engine output torque due to misjudgment, thus reducing the driving experience.

[0085] Example 2:

[0086] Based on the control method of the lock-up clutch control system of the hydraulic torque converter described above, this embodiment provides a specific control method of the lock-up clutch control system of the hydraulic torque converter.

[0087] First, the vehicle controller determines whether the lock-up clutch is malfunctioning based on factors such as: slight speed overspeed in overdrive, vibration or noise from the lock-up clutch, high temperatures in the torque converter due to clutch slippage, and engine stalling during emergency braking. This malfunction information is then sent to the transmission controller. Upon receiving the malfunction information from the vehicle controller, the transmission controller checks whether all self-cleaning conditions are met simultaneously.

[0088] The self-cleaning conditions include: no fault codes inside the transmission controller; engine speed above 1200 rpm; transmission oil temperature between 20℃ and 110℃; throttle opening greater than 10%; target lock-up capacity of the torque converter greater than 1.5 times the engine torque and exceeding 300ms; speed difference between engine speed and turbine speed greater than 100 rpm and exceeding 300ms; and slip friction work of the lock-up clutch greater than 60% of the work corresponding to the hardware protection pressure threshold.

[0089] When the above self-cleaning activation conditions are met simultaneously, the self-cleaning flag in the transmission controller is activated, and the self-cleaning strategy begins. Specifically, a pulse with an amplitude of 800 N·m is generated every 30 ms, and the pulse duration is 20 ms, until 5 pulses are generated, completing one self-cleaning cycle. After completing one self-cleaning cycle, an attempt is made to lock the lock-up clutch. If it can lock, the self-cleaning strategy is exited. If it cannot lock, the self-cleaning strategy is re-executed. After re-execution, if the lock-up clutch can lock, the self-cleaning strategy is exited; if it cannot lock, a fault code is output to the transmission controller. The transmission controller outputs fault information to the vehicle controller based on the fault code. At the same time, the transmission controller determines whether the current lock-up oil pressure is less than 100 kPa and whether the oil pressure change rate of the lock-up oil circuit is greater than 50 kPa / min. If so, the vehicle controller keeps the exhaust light on the instrument panel constantly illuminated and limits the engine output torque to the range of 150 N·m to 200 N·m. If not, the vehicle controller will control the exhaust lights on the instrument panel to illuminate in a breathing pattern and limit the engine's output torque to the range of 100 N·m to 150 N·m.

[0090] Further, refer to Figure 4 When the self-cleaning activation flag is activated, a rectangular wave pulse is generated. At this time, the actual lock-up capacity of the hydraulic torque converter is significantly different from the target lock-up capacity.

[0091] refer to Figure 5 In the first stage, when starting by pressing the accelerator, if the lock-up clutch locks abnormally, there will be a large difference between the engine speed and the turbine speed (the upper part of the speed curve represents the engine speed and the lower part represents the turbine speed). The engine output torque is normal, the target lock-up capacity of the hydraulic torque converter gradually increases from 0, and the slip friction work of the lock-up clutch also increases from 0 along with the target lock-up capacity. At this time, no fault code is reported.

[0092] In the second stage, the hydraulic circuit self-cleaning is performed (self-cleaning count begins). The difference between the engine speed and the turbine speed still exists. The engine output torque is normal. The target lock-up capacity of the hydraulic torque converter changes stepwise. The slip friction work of the lock-up clutch is 0. At this time, no fault code is reported.

[0093] In the third stage, another attempt is made to lock up. When the lock-up is successful, the difference between the engine speed and the turbine speed gradually decreases until they are synchronized. The engine output torque is normal, the target lock-up capacity of the hydraulic torque converter gradually increases, and the slip friction work of the lock-up clutch also increases from a certain value along with the target lock-up capacity.

[0094] refer to Figure 6 The first stage is the regular initial stage, and... Figure 5 The curve changes are consistent with those in the first stage.

[0095] The second stage is the self-cleaning stage of the hydraulic circuit, which is related to... Figure 5 The curve changes are consistent with those in the second stage.

[0096] The third stage is the stage where the lock-up attempt fails again. In this stage, the lock-up capacity of the torque converter (TC) gradually increases from a certain value and then tends to stabilize. The slip friction work of the lock-up clutch also increases from 0 along with the target lock-up capacity.

[0097] The fourth stage involves repeated attempts at self-cleaning and locking of the hydraulic circuit. During this stage, the target lock-up capacity of the torque converter changes in a stepwise manner, the self-cleaning count is incremented by one, the slip friction work of the lock-up clutch is zero, and no fault code is reported.

[0098] The fifth stage is when multiple attempts at self-cleaning are still ineffective. At this stage, the lock-up clutch (TCC) still cannot lock up, the lock-up capacity of the torque converter (TC) gradually increases from a certain value and then tends to stabilize, the slip friction work of the lock-up clutch also increases from 0 along with the target lock-up capacity, reaches its peak and then drops to 0, and the number of self-cleaning times reaches the threshold. At this time, the slip friction work is allowed to exceed the limit and a fault code is reported.

[0099] Example 3:

[0100] Based on the control method for the lock-up clutch control system of the hydraulic torque converter provided in the foregoing embodiments, this embodiment provides a transmission controller. The transmission controller includes a memory and a processor. The transmission controller is an integrated circuit capable of data storage and processing. The memory is used to store the control program.

[0101] When the processor processes the control program, it executes the steps of the control method for the lock-up clutch control system of the hydraulic torque converter as described in the above embodiment.

[0102] Example 4:

[0103] Based on the transmission controller provided in the foregoing embodiments, this embodiment also provides a vehicle including the transmission controller described in the above embodiments.

[0104] Vehicles equipped with the aforementioned transmission controller will implement a self-cleaning strategy when the lock-up clutch fails to engage properly. This eliminates occasional jamming that could prevent the lock-up clutch from engaging properly, thus improving driving safety. Furthermore, it eliminates the need to report a fault to the vehicle controller or prompt the driver for repairs, enhancing the driving experience.

[0105] While the present invention has been illustrated and described with reference to certain preferred embodiments, those skilled in the art should understand that the above description is a further detailed explanation of the invention in conjunction with specific embodiments, and should not be construed as limiting the specific implementation of the invention to these descriptions. Various changes in form and detail can be made by those skilled in the art, including several simple deductions or substitutions, without departing from the spirit and scope of the invention.

Claims

1. A control method for a lock-up clutch control system of a hydraulic torque converter, characterized in that, The control system for the lock-up clutch of the hydraulic torque converter includes: a pressure regulating assembly, a lock-up oil circuit, and a release oil circuit; wherein... The pressure regulating component is connected to the transmission controller, which is also connected to the vehicle controller. The input ends of both the lock-up oil circuit and the disengagement oil circuit are connected to the pressure regulating component, and their output ends are connected to the lock-up clutch of the torque converter. The pressure regulating component adjusts the pressure of the oil flowing through the lock-up oil circuit and the disengagement oil circuit according to a control signal from the transmission controller to control the locking and / or disengagement of the lock-up clutch. The control method includes: S1: The transmission controller obtains vehicle status information from the vehicle controller and determines whether the lock-up clutch control system meets preset self-cleaning activation conditions based on the vehicle status information and the fault information of the transmission controller; wherein, the preset self-cleaning activation conditions include: no fault codes inside the transmission controller; engine speed higher than a preset speed threshold; transmission oil temperature within a preset temperature range; throttle opening greater than a preset opening threshold; the target lock-up capacity of the torque converter higher than a preset difference in engine torque for a preset time; the speed difference between engine speed and turbine speed greater than a preset speed difference threshold; and the slip friction work of the lock-up clutch greater than the preset slip friction work threshold. If so, proceed to step S2; If not, then continue to determine whether the control system of the lock-up clutch simultaneously meets all the preset self-cleaning activation conditions; S2: The transmission controller controls the pressure regulating component using a preset self-cleaning control strategy; S3: The transmission controller controls the lock-up clutch to relock, and determines whether the relocking is successful based on the relationship between the sliding friction work of the lock-up clutch and the preset sliding friction work threshold. If successful, control is terminated; If unsuccessful, repeat steps S2 and S3 until the number of times the locking clutch relocks reaches a preset number, and then execute step S4; wherein, if the slip friction work of the locking clutch is greater than the slip friction work threshold, it is determined that the locking is unsuccessful; if the slip friction work of the locking clutch is less than or equal to the slip friction work threshold, it is determined that the locking is successful. S4: The transmission controller outputs fault information indicating that the lock-up clutch cannot lock properly to the vehicle controller, and the vehicle controller generates and sends alarm information based on the fault information.

2. The control method for the lock-up clutch control system of the hydraulic torque converter as described in claim 1, characterized in that, In step S1, the vehicle status information includes: Engine speed, transmission oil temperature, throttle opening, target lock-up capacity of the torque converter, engine torque, turbine speed, and slip friction work of the lock-up clutch.

3. The control method for the lock-up clutch control system of the hydraulic torque converter as described in claim 2, characterized in that, The preset speed threshold ranges from 1200 rpm to 1400 rpm; The preset temperature range is 20℃ to 110℃; The preset opening threshold ranges from 5% to 15%; The preset time ranges from 300ms to 600ms; The preset difference is 0.5 to 1 times the engine torque; The preset speed difference threshold is 100 rpm to 200 rpm; The preset friction work threshold is 60% to 80% of the work corresponding to the hardware protection pressure threshold of the hydraulic torque converter.

4. The control method for the lock-up clutch control system of the hydraulic torque converter as described in claim 3, characterized in that, In step S2, the preset self-cleaning control strategy includes: The pressure regulating component outputs a pulse corresponding to the target lock-up capacity of the hydraulic torque converter until the number of pulses output to the pressure regulating component reaches a preset number of pulses; wherein The pulse corresponding to the target lock-up capacity of the hydraulic torque converter is a rectangular wave. The amplitude of the pulse is determined based on the transmission oil temperature and the hardware protection pressure threshold of the torque converter. The period of the pulse is determined based on the transmission oil temperature.

5. The control method for the control system of the lock-up clutch of the hydraulic torque converter as described in claim 4, characterized in that, The period of the pulse is in the range of 20ms to 50ms; The amplitude of the pulse is in the range of 5 bar to 8 bar; The preset number of pulses is 4 to 6; and In step S3, the preset number of times ranges from 2 to 4.

6. The control method for the control system of the lock-up clutch of the hydraulic torque converter as described in claim 1, characterized in that, In step S4, the vehicle controller generates and sends alarm information based on the fault information, including: The vehicle controller generates and sends alarm information to the vehicle instrument panel to illuminate the exhaust lights based on the fault information; and An alarm message is sent to the engine controller to limit the engine's output torque to a preset torque range; wherein the preset torque range is 100 N·m to 200 N·m.

7. The control method for the lock-up clutch control system of the hydraulic torque converter as described in claim 6, characterized in that, The voltage regulating component includes: A solenoid valve, the input end of which is connected to the transmission controller, receives control signals from the transmission controller; The pressure regulating slide valve has its input end connected to the output end of the solenoid valve via a control oil circuit, and its output end is connected to the input end of the separation oil circuit and the input end of the locking oil circuit, respectively.

8. The control method for the lock-up clutch control system of the hydraulic torque converter as described in claim 7, characterized in that, In step S4, when the transmission controller outputs the fault information, it further includes: The hydraulic pressure information of the locking hydraulic circuit is output to the vehicle controller; wherein, the hydraulic pressure information of the locking hydraulic circuit includes the hydraulic pressure of the locking hydraulic circuit and the rate of change of the hydraulic pressure of the locking hydraulic circuit; and The vehicle controller generates and sends alarm information based on the fault information, and also includes: Determine whether the oil pressure of the locking oil circuit is lower than a preset oil pressure threshold and whether the oil pressure change rate of the locking oil circuit is greater than a preset change rate threshold. If not, the exhaust lights are kept on and the engine output torque is limited to the range of 150 N·m to 200 N·m. If so, the exhaust light is kept constantly on, and the engine output torque is limited to the range of 100 N·m to 150 N·m.

9. A gearbox controller, characterized in that, include: The memory is used to store the control program; A processor, which, when processing the control program, executes the steps of a control method for a lock-up clutch control system of a hydraulic torque converter as described in any one of claims 1-8.

10. A vehicle, characterized in that, Includes the gearbox controller as described in claim 9.

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