Clutch control method for power-shift transmissions and related devices

Abstract

The application relates to the technical field of clutch control, in particular to a clutch control method of a power shift gearbox and related equipment, which starts an engine at a preset engine speed in a clutch calibration mode, determines a target clutch and a counter clutch, controls the gearbox to engage in a counter gear position, monitors a speed difference between a current engine speed and a current gearbox input shaft speed to establish a speed difference monitoring benchmark, controls the gearbox to engage in a target gear position, monitors the speed difference to generate a slip and friction combination mark of the target clutch, corrects an oil filling time period of the target clutch according to a located interval of the slip and friction combination mark on the oil filling time period, completes calibration of the clutch, and the calibration process does not depend on a pressure sensor, so that the manufacturing cost of the gearbox can be reduced.

Description

Technical Field

[0001] This application relates to the field of clutch control technology, and in particular to clutch control methods and related equipment for power shift transmissions. Background Technology

[0002] In engineering vehicles, the power shift transmission achieves different gear ratios through the engagement and disengagement of multiple sets of hydraulic clutch friction plates. Ideally, the hydraulic clutches engage immediately after their oil chambers are filled, achieving power transmission. However, due to variations in the volumetric efficiency of the transmission pump, machining and manufacturing deviations, and individual differences in the friction plates, the critical time for each hydraulic clutch to fill its oil chamber and begin slip engagement varies significantly. Therefore, it is necessary to calibrate the oil filling time of the oil chambers before shipment. Furthermore, as the engineering vehicle operates, the clutch friction plates wear, leading to an increase in the engagement clearance. This necessitates recalibrating the clutch oil filling time.

[0003] In related technologies, the calibration of power shift transmissions relies on pressure sensors in the oil circuits of each clutch. The critical time for slip engagement is determined by the oil pressure abrupt change points monitored by the pressure sensors, and then the oil filling time of the oil chamber is calibrated using the critical time for slip engagement. The installation of pressure sensors increases the manufacturing cost of the transmission. Summary of the Invention

[0004] In view of this, embodiments of this application propose a clutch control method and related equipment for a power shift transmission, which can calibrate the clutch of the power shift transmission without relying on pressure sensors, thus helping to reduce the manufacturing cost of the transmission.

[0005] To achieve the above objectives, one aspect of this application proposes a clutch control method for a power shift transmission, the method comprising: In clutch calibration mode, the engine is started at a preset engine speed to determine the target clutch and the opposite clutch, wherein the target clutch and the opposite clutch are in a non-same-end transmission relationship. Control the closing of the opposing clutch, monitor the current speed difference between the current engine speed and the current transmission input shaft speed, and generate a slip engagement flag when the target clutch enters the slip engagement state based on the current speed difference between the engine speed and the transmission input shaft speed. The initial oil filling time period of the target clutch is determined, and the initial oil filling time period is corrected according to the interval of the slip-friction engagement indicator in the initial oil filling time period of the target clutch to obtain the corrected oil filling time period.

[0006] In some embodiments, generating a slip engagement indicator when the target clutch enters a slip engagement state based on the current speed difference between the engine speed and the transmission input shaft speed includes: Determine whether the current speed difference is less than or equal to the preset speed difference. If so, generate the slip-friction engagement flag at the current time step.

[0007] In some embodiments, the oil filling time period includes a fast charging range, a pressure holding range, and a pressure boosting range; The step of correcting the initial oil filling time period based on the location of the slip-and-grip engagement indicator within the initial oil filling time period of the target clutch to obtain the corrected oil filling time period includes: Poll the aforementioned friction engagement indicator; If the slip-fist engagement flag is found within the fast-charging interval of the initial oil filling time period, the fast-charging interval of the initial oil filling time period is reduced by a standard duration to obtain the corrected oil filling time period. Then, the execution steps are returned: control the closing of the opposite clutch and monitor the current speed difference between the current engine speed and the current transmission input shaft speed. If the slip-fist engagement flag is not found within the pressure holding interval of the initial oil filling time period and after the preset pressure holding time upper limit, then the fast charging interval or pressure holding interval of the initial oil filling time period is increased by a standard duration to obtain the corrected oil filling time period, and the execution steps are returned: control the closing of the opposite clutch, and monitor the current speed difference between the current engine speed and the current transmission input shaft speed; If the slip-fist engagement flag is found within the pressure holding range of the initial oil filling time period and before the preset pressure holding time upper limit, then the initial oil filling time period is taken as the corrected oil filling time period, and the clutch calibration mode is exited.

[0008] In some embodiments, if the slip-fitting engagement flag is not found within the pressure holding interval of the initial oil filling time period and after a preset pressure holding time upper limit, then adding a standard duration to the fast charging interval or pressure holding interval of the initial oil filling time period includes: If the pressure holding interval of the initial oil filling time period does not reach the maximum oil filling time limit, then the pressure holding interval of the initial oil filling time period will be increased by a standard duration. If the pressure holding interval of the initial oil filling time period has reached the maximum oil filling time limit, then the fast charging interval of the initial oil filling time period will be increased by a standard duration, and the pressure holding interval will be reset to the initial duration.

[0009] In some embodiments, the method further includes: After obtaining the corrected oil filling time period, the calibration count is reset to 0, and the execution steps are returned: control the closing of the opposite clutch, and monitor the current speed difference between the current engine speed and the current transmission input shaft speed; After using the initial oil filling time period as the corrected oil filling time period, the calibration count is increased by 1. When the calibration count reaches a preset number, the clutch calibration mode is exited.

[0010] In some embodiments, the method further includes: In response to the command to calibrate the target clutch, the transmission oil temperature, the position of the travel lever, and the vehicle's driving status are acquired; The system determines whether preset operating conditions are met based on the transmission oil temperature, the position of the travel lever, and the vehicle's travel status. If the conditions are met, the system enters the clutch calibration mode; otherwise, an alarm message is sent.

[0011] To achieve the above objectives, another aspect of this application provides a clutch control device for a power shift transmission, the device comprising: The starting module is used to start the engine at a preset engine speed in clutch calibration mode, and to determine the target clutch and the opposite clutch, wherein the target clutch and the opposite clutch are in a non-same-end transmission relationship. The speed difference determination module is used to control the closing of the opposite clutch and monitor the current speed difference between the current engine speed and the current transmission input shaft speed. A flag generation module is used to generate a slip engagement flag when the target clutch enters a slip engagement state, based on the current speed difference between the engine speed and the gearbox input shaft speed. The correction module is used to determine the initial oil filling time period of the target clutch, and correct the initial oil filling time period according to the interval of the slip-friction engagement mark in the initial oil filling time period of the target clutch to obtain the corrected oil filling time period.

[0012] To achieve the above objectives, another aspect of this application provides an electronic device, which includes a memory and a processor. The memory stores a computer program, and the processor executes the computer program to implement the methods described above.

[0013] To achieve the above objectives, another aspect of the embodiments of this application proposes a computer-readable storage medium storing a computer program that, when executed by a processor, implements the methods described above.

[0014] To achieve the above objectives, another aspect of the embodiments of this application proposes a computer program product, including a computer program that, when executed by a processor, implements the methods described above.

[0015] To achieve the above objectives, another aspect of this application provides an engineering vehicle equipped with a power shift gearbox and a clutch controller, the clutch controller being used to perform the steps described above.

[0016] The embodiments of this application include at least the following beneficial effects: This application provides a clutch control method and related equipment for a power shift transmission. This method involves starting the engine at a preset engine speed in clutch calibration mode, determining a target clutch and a counter-end clutch (the target clutch and the counter-end clutch are not in a same-end transmission relationship); controlling the counter-end clutch to close, monitoring the current speed difference between the current engine speed and the current transmission input shaft speed, and generating a slip-fitting engagement flag when the target clutch enters a slip-fitting engagement state based on the current speed difference between the engine speed and the transmission input shaft speed; determining the initial oil filling time period of the target clutch, and correcting the initial oil filling time period based on the interval where the slip-fitting engagement flag is located within the initial oil filling time period of the target clutch to obtain a corrected oil filling time period. When the target gear is switched to the counter-end gear, if the slip-fitting engagement flag is found to be generated before the oil chamber is fully filled or after the oil chamber has been filled for a long time, it indicates an error in the oil filling time period of the target clutch oil chamber. After correction, the slip-fitting engagement state occurs exactly after the oil chamber is fully filled, thus reducing jerking when the target clutch engages. Moreover, the calibration process does not rely on pressure sensors, which helps reduce transmission manufacturing costs. Attached Figure Description

[0017] Figure 1 This is a flowchart of the clutch control method for a power shift transmission provided in an embodiment of this application; Figure 2 This is a flowchart of the step of generating the friction-bonding mark in the method shown in the embodiments of this application; Figure 3 This is a flowchart of the step of determining the pre-locking condition in the method shown in the embodiments of this application; Figure 4 This is a schematic diagram illustrating the relationship between the oil filling time period and the hydraulic pump drive current provided in the embodiments of this application; Figure 5 This is another flowchart of the clutch control method for the power shift transmission provided in the embodiments of this application; Figure 6 This is a schematic diagram of the clutch control device of the power shift transmission provided in the embodiments of this application; Figure 7This is a schematic diagram of the hardware structure of the electronic device provided in the embodiments of this application. Detailed Implementation

[0018] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of this application and are not intended to limit it. In the following description, when referring to the accompanying drawings, unless otherwise indicated, the same numbers in different drawings represent the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with those of this application; they are merely examples of apparatuses and methods consistent with some aspects of the embodiments of this application as detailed in the appended claims.

[0019] It is understood that the terms “first,” “second,” etc., used in this application may be used herein to describe various concepts, but unless otherwise stated, these concepts are not limited by these terms. These terms are only used to distinguish one concept from another. For example, without departing from the scope of the embodiments of this application, first information may also be referred to as second information, and similarly, second information may also be referred to as first information. Depending on the context, the words “if,” “when,” or “in response to a determination” as used herein may be interpreted as “when…” or “when…” or “in response to a determination.”

[0020] As used in this application, the terms "at least one", "multiple", "each", "any", etc., "at least one" includes one, two or more, "multiple" includes two or more, "each" refers to each of the corresponding multiples, and "any" refers to any one of the multiples.

[0021] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used herein is for the purpose of describing embodiments of this application only and is not intended to limit this application.

[0022] Before providing a detailed description of the embodiments of this application, some of the nouns and terms involved in the embodiments of this application will be explained first. The nouns and terms involved in the embodiments of this application are subject to the following interpretations.

[0023] In engineering vehicles, the power shift transmission achieves different gear ratios through the engagement and disengagement of multiple sets of hydraulic clutch friction plates. Ideally, the hydraulic clutches engage immediately after their oil chambers are filled, achieving power transmission. However, due to variations in the volumetric efficiency of the transmission pump, machining and manufacturing deviations, and individual differences in the friction plates, the critical time for each hydraulic clutch to fill its oil chamber and begin slip engagement varies significantly. Therefore, it is necessary to calibrate the oil filling time of the oil chambers before shipment. Furthermore, as the engineering vehicle operates, the clutch friction plates wear, leading to an increase in the engagement clearance. This necessitates recalibrating the clutch oil filling time.

[0024] In related technologies, the calibration of power shift transmissions relies on pressure sensors in the oil circuits of each clutch. The critical time for slip engagement is determined by the oil pressure abrupt change points monitored by the pressure sensors, and then the oil filling time of the oil chamber is calibrated using the critical time for slip engagement. The installation of pressure sensors increases the manufacturing cost of the transmission.

[0025] In view of this, this application provides a clutch control method for a power shift transmission. This method establishes a speed difference monitoring benchmark by controlling the transmission to engage at the opposite gear, controls the transmission to engage at the target gear, monitors the speed difference to determine the critical time for the target clutch to enter the slip-fist engagement state, and corrects the oil filling time period based on the range of the critical time in the target clutch's oil filling time period to complete the clutch calibration. The calibration process does not rely on pressure sensors, which helps to reduce the transmission manufacturing cost.

[0026] The clutch control method for a power shift transmission provided in this application relates to the field of clutch control technology. This clutch control method can be applied to a vehicle controller, an edge controller, or software running on an onboard computing platform or terminal. The vehicle controller or edge controller can be configured as a vehicle controller, a power domain controller, a chassis domain controller, a clutch controller, or an electronic control unit, etc. These controllers can be configured as independent physical control modules, or as a domain controller or central computing platform composed of multiple integrated control modules, or as onboard computing nodes providing real-time calculation, data fusion, and control algorithm execution. The software can be an application program or underlying firmware implementing the clutch control method for the power shift transmission, but is not limited to these forms.

[0027] This application can be used in numerous general-purpose or special-purpose computer system environments or configurations. Examples include: vehicle controllers, transmission controllers, electronic control units, domain controllers, in-vehicle computing platforms, and distributed computing environments including any of the above systems or devices. This application can be described in the general context of computer-executable instructions executed by a computer, such as program modules. Generally, program modules include routines, programs, objects, components, data structures, etc., that perform specific tasks or implement specific abstract data types. This application can also be practiced in distributed computing environments where tasks are performed by remote processing devices connected via in-vehicle communication networks (such as CAN bus, in-vehicle Ethernet, etc.) or external communication networks. In distributed computing environments, program modules can reside in local and remote computer storage media, including storage devices.

[0028] Figure 1 This is an optional flowchart of the clutch control method for a power shift transmission provided in this application embodiment. Figure 1 The method may include, but is not limited to, steps 101 to 104.

[0029] Step 101: In clutch calibration mode, start the engine at a preset engine speed and determine the target clutch and the opposite clutch, wherein the target clutch and the opposite clutch are in a non-same-end transmission relationship. The controller of the power shift transmission has a pre-set clutch calibration program. This program is entered before the transmission leaves the factory or when the transmission in a construction vehicle experiences severe jerking. In this state, the transmission is in clutch calibration mode. In step 101, in this clutch calibration mode, the controller starts the engine and runs it at a preset engine speed. The target clutch and the opposing clutch can be determined by the user-selected target gear and the opposing gear, or by querying a preset lookup table.

[0030] It is understandable that in a power shift transmission, one set of clutches is installed on one drive shaft of the transmission, while another set of clutches is installed on another drive shaft. Any two clutches belonging to two different drive shafts constitute this non-same-end transmission relationship.

[0031] Step 102: Control the engagement of the opposite clutch and monitor the current speed difference between the current engine speed and the current transmission input shaft speed; In step 102, the oil chamber of the opposite clutch is controlled to start filling with oil. After the oil filling is completed, it is connected to the input shaft of the gearbox, and the engine power is input. The current engine speed and the gearbox input shaft speed are collected by the sensor.

[0032] Step 103: Based on the current speed difference between the engine speed and the gearbox input shaft speed, generate a slip engagement flag when the target clutch enters a slip engagement state; In step 103, the target clutch's oil chamber begins to fill with oil. After filling, it connects to the transmission input shaft, and engine power is transmitted from the transmission input shaft, the opposing clutch, and the target clutch. During the oil filling process of the target clutch's oil chamber, the speed difference between the engine speed and the transmission input shaft speed is calculated and judged in real time. At the instant the target clutch enters the slip engagement state, the transmission input shaft speed is reduced, and the speed difference begins to increase. When the calculated speed difference reaches a specific speed difference threshold, it is determined that the target clutch has entered the slip engagement state, and a slip engagement flag is generated at the current time step.

[0033] Step 104: Determine the initial oil filling time period of the target clutch, and correct the initial oil filling time period according to the interval of the slip-friction engagement mark in the initial oil filling time period of the target clutch to obtain the corrected oil filling time period.

[0034] Understandably, it takes time for the clutch oil chamber to fill. At the start of filling, a first current drives a large hydraulic thrust to rapidly fill the oil, quickly eliminating the free play gap on the target clutch's friction plates. After a certain time, a second current drives a small hydraulic thrust to maintain pressure in the oil chamber. Once the target clutch is fully engaged, the second current is increased to a third current, driving the hydraulic pump to increase the hydraulic thrust. Therefore, the filling time period is divided into several intervals according to the control sequence of the first, second, and third currents. Ideally, the moment the clutch enters the slip-and-grip engagement state should be within the interval of the second current.

[0035] Steps 101 to 104, as illustrated in this embodiment, involve starting the engine at a preset engine speed in clutch calibration mode to determine the target clutch and the opposing clutch, which are in a non-coaxial transmission relationship. The opposing clutch is controlled to close, and the current speed difference between the current engine speed and the current transmission input shaft speed is monitored. Based on this difference, a slip-fitting engagement flag is generated when the target clutch enters a slip-fitting engagement state. The initial oil filling time period of the target clutch is determined, and the initial oil filling time period is corrected based on the location of the slip-fitting engagement flag within this period, resulting in a corrected oil filling time period. When the target gear is switched to the opposing gear, if the slip-fitting engagement flag is found to be generated before the oil chamber is fully filled or after a considerable time has passed since the oil chamber is filled, it indicates an error in the oil filling time period of the target clutch oil chamber. After correction, the slip-fitting engagement state occurs precisely after the oil chamber is fully filled. This reduces jerking during target clutch engagement. Furthermore, the calibration process does not rely on pressure sensors, which helps reduce transmission manufacturing costs.

[0036] See Figure 2 In some embodiments, generating a slip engagement flag when the target clutch enters a slip engagement state based on the current speed difference between the engine speed and the transmission input shaft speed includes: Step 201: Determine whether the current speed difference is less than or equal to the preset speed difference.

[0037] When the clutch at the opposite end is engaged, the controller begins to periodically read the engine speed and transmission input shaft speed collected by the sensors, calculates the difference between the two, and obtains the current speed difference at the current time step.

[0038] Step 202: If so, generate the slip-friction engagement flag at the current time step; Step 203, if not, return to the following steps: obtain the engine speed and the gearbox input shaft speed at the current time step.

[0039] Since the opposing clutch is locked, if the target clutch's oil chamber is fully filled and begins to engage, the transmission input shaft speed will deviate significantly from the engine speed. After calculating the current speed difference at each time step, the current speed difference is compared to the preset speed difference. If the current speed difference is greater than the preset speed difference, it indicates that the transmission input shaft speed has not significantly deviated from the engine speed, and the target clutch has not entered a slip-fitting engagement state. If the current speed difference is smaller than the preset speed difference, it indicates that the transmission input shaft speed has significantly deviated from the engine speed, and the target clutch has entered a slip-fitting engagement state. A slip-fitting engagement indicator is generated at this time step.

[0040] In this embodiment, before calibrating the target clutch, a counter-clutch that forms a non-same-end transmission relationship with the target clutch is first engaged, but the transmission chain is disconnected at the target clutch to be calibrated. The rotational inertia of the engaged counter-clutch is used to apply a load to the gearbox input shaft, so that the gearbox input shaft speed is stabilized within a certain range. In this way, when the target clutch is engaged, the sensor can accurately capture the minute changes in the gearbox input shaft speed caused by the target clutch entering the slip-friction engagement state.

[0041] Furthermore, compared to directly monitoring the speed change of the transmission input shaft, calculating the speed difference can eliminate the influence of engine speed fluctuations. The load environment (oil temperature, system pressure, etc.) during calibration may have slight fluctuations, which will affect the speed value. However, the slip ratio is a relative relationship, and the disturbance is partially offset, making the judgment result more stable and reliable.

[0042] In some embodiments, the oil filling time period includes a fast filling interval, a pressure holding interval, and a pressure boosting interval. The step of correcting the initial oil filling time period based on the location of the slip-and-grip engagement indicator within the initial oil filling time period of the target clutch, to obtain a corrected oil filling time period, includes: Step 301: Poll the friction engagement indicator; Step 302: If the slip-fist engagement flag is found within the fast-charging interval of the initial oil filling time period, the fast-charging interval of the initial oil filling time period is reduced by a standard duration to obtain the corrected oil filling time period. Then, return to the execution steps: control the closing of the opposite clutch and monitor the current speed difference between the current engine speed and the current transmission input shaft speed. If friction plate slippage occurs when the fast charging timer is not triggered or when the pressure holding period has just begun, it indicates that the clutch is overfilled with oil due to the current fast charging duration being too long. The fast charging interval of the initial oil filling period is reduced by a preset value (standard duration), and the process jumps to reset and drain oil to restart the calibration.

[0043] Step 303: If the slip-fist engagement flag is not found within the pressure holding interval of the initial oil filling time period and after the preset pressure holding time upper limit, then add a standard duration to the fast charging interval or pressure holding interval of the initial oil filling time period to obtain the corrected oil filling time period, and return to the execution step: control the closing of the opposite clutch and monitor the current speed difference between the current engine speed and the current transmission input shaft speed. When the pressure holding time has reached the preset pressure holding time limit, but no engagement still occurs, it is determined that the current fast charging interval is seriously insufficient, resulting in a shortage of base oil. At this time, the fast charging interval is incremented by 1, the pressure holding interval is reset to the initial value, and then the system is forcibly switched to reset and drain oil to restart a new round of automatic calibration.

[0044] Step 304: If the slip-fist engagement flag is found within the pressure holding range of the initial oil filling time period and before the preset pressure holding time upper limit, then the initial oil filling time period is taken as the corrected oil filling time period, and the clutch calibration mode is exited.

[0045] If the critical time is within the pressure holding range, the current time parameter is determined to be close to the actual physical characteristics of the clutch, and the duration of each range is kept unchanged.

[0046] In this embodiment, when calibrating the target clutch, if the timing of slip engagement is incorrect (e.g., not engaging for a long time or engaging too early), the duration of the pressure holding interval is first accumulated. When the duration of the pressure holding interval reaches the upper limit, it is automatically determined that the large volume oil chamber is not filled due to insufficient duration of the fast charging interval. The duration of the fast charging interval is incremented and updated, while the duration of the pressure holding interval is reset to zero. This control architecture can accurately calibrate the oil filling duration of multiple intervals of each clutch through dual-level cascaded adaptive updates.

[0047] In some embodiments, if the slip-fitting engagement flag is not found within the pressure holding interval of the initial oil filling time period and after a preset pressure holding time upper limit, then adding a standard duration to the fast charging interval or pressure holding interval of the initial oil filling time period includes: Step 3031: If the pressure holding interval of the initial oil filling time period does not reach the maximum oil filling time limit, then the pressure holding interval of the initial oil filling time period is increased by a standard duration. Step 3032: If the pressure holding interval of the initial oil filling time period has reached the maximum oil filling time limit, then the fast charging interval will be increased by a standard duration, and the pressure holding interval will be reset back to the initial duration.

[0048] In this embodiment, if the sliding wear determination is not triggered when the pressure holding interval reaches the upper limit of the preset pressure holding time, it indicates that the oil filling amount is seriously insufficient. The controller executes steps 3031 to 3032, which can reduce the number of calibrations.

[0049] In some embodiments, after correcting the initial oil filling time period to obtain a corrected oil filling time period, the method further includes: Step 401: After obtaining the corrected oil filling time period, reset the calibration count to 0 and return to the execution steps: control the closing of the opposite clutch and monitor the current speed difference between the current engine speed and the current transmission input shaft speed.

[0050] Step 402: After using the initial oil filling time period as the corrected oil filling time period, the calibration count is increased by 1. When the calibration count reaches the preset count, the clutch calibration mode is exited.

[0051] In this embodiment, the calibration count is determined. If the number of calibrations is less than 3, the clutch is repositioned and drained before recalibrating. When the number of calibrations is 3, the target clutch is considered successfully calibrated, thus eliminating interference from external factors.

[0052] In some embodiments, the method further includes: Step 501: In response to the instruction to calibrate the target clutch, acquire the transmission oil temperature, the position of the travel lever, and the vehicle's driving status; Step 502: Determine whether the preset operating conditions are met based on the transmission oil temperature, the position of the travel lever, and the vehicle's driving status. If the conditions are met, enter the clutch calibration mode; if not, send an alarm message.

[0053] In this embodiment, after receiving the clutch calibration command, the system first determines the pre-lock conditions of the entire machine. If the conditions are met, such as the engine speed being greater than or equal to the preset engine speed, the transmission oil temperature being within the preset oil temperature range, the entire machine being in the parking lock state, and the travel handle being in the neutral position, the system enters the clutch calibration mode. If any condition is not met, the instrument displays a prompt indicating that the current condition is not met, to prevent accidental entry into the clutch calibration mode.

[0054] The following is a detailed description and explanation of the solutions in the embodiments of the present invention, using specific application examples: This application provides a clutch control method for a power shift transmission, which can be used to calibrate the clutch of the power shift transmission.

[0055] See Figure 3 The controller first determines the pre-lock conditions of the machine by triggering the clutch calibration mode through the instrument. If the conditions are met, such as the engine speed being greater than or equal to 1900 rpm / min, the transmission oil temperature being between 50℃ and 90℃, the machine being in the parking lock state, and the travel handle being in the neutral position, the controller executes the automatic calibration program. If any condition is not met, the instrument displays a prompt indicating that the current condition is not met.

[0056] See Figure 4 The oil filling time period includes the fast charging interval (rapid oil filling stage), the pressure holding interval (pressure holding stage), and the pressure boosting interval (rapid pressure boosting stage). Initialization is performed before calibration begins, with the vehicle controller assigning initial values ​​to the oil filling time period. At this time, the duration variable (TUpCali) of the fast charging interval is set to 7 (corresponding to 70ms), the duration variable (TKeepCali) of the pressure holding interval is set to 5 (corresponding to 50ms), and the continuous cycle verification counter (CycleCount) and the friction plate engagement flag (TempComp) are cleared to zero.

[0057] See Figure 5After the pre-locking condition is met, assuming the current calibration target is a forward gear clutch, in order to establish a clear comparison of speed change characteristics, the controller outputs a 900mA saturation current to the hydraulic pump of the 1st gear clutch (opposite clutch) on a different transmission path, causing the friction plates of the 1st gear clutch (opposite clutch) to completely close and lock, forcibly establishing a speed-damped transmission chain. Similarly, if the current calibration target is a speed gear clutch (1st, 2nd, or 3rd gear), the controller outputs a 900mA saturation current to the hydraulic pump of the forward gear clutch (target clutch) on a different transmission path, causing the friction plates of the forward gear clutch to completely close and lock.

[0058] The hydraulic pump-driven oil filling strategy includes: outputting a timing waveform current to the hydraulic pump of the forward gear clutch: first, activating the fast-charging timer, outputting a high current of 900mA during the fast-charging range, and using the large hydraulic thrust to quickly eliminate the idle travel gap of the friction plates. The fast-charging timer duration calculation formula is based on dynamic adjustment of TUpCali: PTUp=TUpCali 10 (milliseconds). After the fast charging timer is triggered, the target clutch solenoid valve current value switches to 330mA, entering the low-current micro-motion pressure holding stage. The formula for the pressure holding timer is: PTKeep = TKeepCali 10 (milliseconds). During target clutch pressure holding, the controller polls the slip engagement flag at high speed every 10ms. The controller reads the engine speed and transmission input shaft speed to calculate the speed difference. When the engine is running at high speed, since the 1st gear clutch (opposite clutch) is locked, if the forward gear clutch (target clutch) is fully filled with oil and begins to engage, the transmission input shaft speed will be pulled down or its speed will deviate significantly from the engine speed. Therefore, when the transmission input shaft speed + 50 < engine speed, or the transmission input shaft speed < 1950 rpm / min, it is determined that slip engagement of the target clutch friction plate has occurred. The friction plate engagement flag data is recorded as 1, indicating that the friction plate engagement flag data is 0, indicating that it does not exist. This is used to determine the existence of the friction plate engagement flag during polling. Combined with the three-way cascaded branch calibration strategy that triggers adaptive calibration, the oil filling time period is modified. 1. In the case of no engagement: If the engagement / slip-fitting engagement flag is still 0 when the pressure holding timer is triggered, the controller will check whether the pressure holding time has reached the maximum pressure holding time threshold of 300ms (i.e., TKeepCali). If 10>300), it indicates that there is only a slight shortage of oil filling. The pressure holding time is incremented step by step (TKeepCali incremented by one), the CycleCount is cleared, the state machine is reset, the forward clutch (target gear) is returned to completely drain the oil, and then the calibration is restarted. If the pressure holding time has reached 300ms, but engagement still has not occurred, the controller determines that the current fast charging time is seriously insufficient, resulting in a shortage of base oil. Simply increasing the pressure holding time cannot make up for it. At this time, the cross-stage cascade reverse logic is triggered - the fast charging time is forcibly incremented (TUpCali incremented by one), while the pressure holding time is reset to the initial value of 5. Then, the system is forcibly jumped to the reset drain oil and restarted a new round of automatic calibration.

[0059] 2. Premature abnormal engagement: If friction plate slip engagement occurs before the fast charging timer is triggered or just as the pressure holding period begins, it indicates that the clutch is overfilled due to the current fast charging duration being too long. The controller will perform a fast charging duration decrement update (TUpCali decrement by one), clear CycleCount, and jump to reset and drain oil to restart calibration.

[0060] 3. Precise Engagement Scenario: If a friction plate slip engagement signal is captured within a reasonable holding time range (<=300ms) (TempComp equals 1), the controller determines that the current time parameter approximates the actual physical characteristics of the clutch, retains TUpCali and TKeepCali, and increments CycleCount by one. To eliminate interference from external factors, the controller checks the value of CycleCount. If CycleCount < 3, it reverts to the previous position, drains oil, and tests again. When slip engagement of the target clutch friction plate is captured three consecutive times (CycleCount equals 3) within the current TUpCali and TKeepCali, the controller ultimately determines that the target clutch calibration is successful.

[0061] After successful calibration, the controller persistently writes the calculated TUpCali and TKeepCali into its internal storage unit, serving as the standard timing parameters for subsequent gear shifts of this model. Finally, the state machine is cleared, the controller cuts off the current output of all clutch solenoid valves, exits the automatic calibration program, and the instrument displays "calibration successful."

[0062] Please see Figure 6 This application also provides a clutch control device for a power shift transmission, which can implement the above-described method. The device includes: The starting module is used to start the engine at a preset engine speed in clutch calibration mode, and to determine the target clutch and the opposite clutch, wherein the target clutch and the opposite clutch are in a non-same-end transmission relationship. The speed difference determination module is used to control the closing of the opposite clutch and monitor the current speed difference between the current engine speed and the current transmission input shaft speed. A flag generation module is used to generate a slip-fit ​​flag correction module when the target clutch enters a slip-fit ​​state based on the current speed difference between the engine speed and the transmission input shaft speed. The correction module is used to determine the initial oil filling time period of the target clutch and correct the initial oil filling time period based on the interval where the slip-fit ​​flag is located in the initial oil filling time period of the target clutch to obtain a corrected oil filling time period.

[0063] It is understood that the content of the above method embodiments is applicable to the present device embodiments. The specific functions implemented by the present device embodiments are the same as those of the above method embodiments, and the beneficial effects achieved are also the same as those achieved by the above method embodiments.

[0064] This application also provides an electronic device, which includes a memory and a processor. The memory stores a computer program, and the processor executes the computer program to implement the above-described method. This electronic device can be any smart terminal, including tablet computers, in-vehicle computers, etc.

[0065] It is understood that the content of the above method embodiments is applicable to this device embodiment. The specific functions implemented by this device embodiment are the same as those of the above method embodiments, and the beneficial effects achieved are also the same as those achieved by the above method embodiments.

[0066] Please see Figure 7 , Figure 7 The hardware structure of an electronic device according to another embodiment is illustrated. The electronic device includes: The processor 701 can be implemented using a general-purpose CPU (Central Processing Unit), microprocessor, application-specific integrated circuit (ASIC), or one or more integrated circuits, and is used to execute relevant programs to implement the technical solutions provided in the embodiments of this application. The memory 702 can be implemented as a read-only memory (ROM), a static storage device, a dynamic storage device, or a random access memory (RAM). The memory 702 can store the operating system and other application programs. When the technical solutions provided in the embodiments of this specification are implemented through software or firmware, the relevant program code is stored in the memory 702 and is called and executed by the processor 701 using the methods described in the embodiments of this application. The input / output interface 703 is used to implement information input and output; The communication interface 704 is used to enable communication and interaction between this device and other devices. Communication can be achieved through wired means (such as USB, Ethernet cable, etc.) or wireless means (such as mobile network, WIFI, Bluetooth, etc.). Bus 705 transmits information between various components of the device (e.g., processor 701, memory 702, input / output interface 703, and communication interface 704); The processor 701, memory 702, input / output interface 703, and communication interface 704 are connected to each other within the device via bus 705.

[0067] This application also provides a computer-readable storage medium storing a computer program that, when executed by a processor, implements the above-described method.

[0068] It is understood that the content of the above method embodiments is applicable to this storage medium embodiment. The specific functions implemented in this storage medium embodiment are the same as those in the above method embodiments, and the beneficial effects achieved are also the same as those achieved in the above method embodiments.

[0069] This application also provides a computer program product, including a computer program that, when executed by a processor, implements the above-described method.

[0070] It is understood that the content of the above method embodiments is applicable to the embodiments of this program product. The specific functions implemented by the embodiments of this program product are the same as those of the above method embodiments, and the beneficial effects achieved are also the same as those achieved by the above method embodiments.

[0071] Memory, as a non-transitory computer-readable storage medium, can be used to store non-transitory software programs and non-transitory computer-executable programs. Furthermore, memory may include high-speed random access memory, and may also include non-transitory memory, such as at least one disk storage device, flash memory device, or other non-transitory solid-state storage device. In some embodiments, memory may optionally include memory remotely located relative to the processor, and these remote memories can be connected to the processor via a network. Examples of such networks include, but are not limited to, the Internet, intranets, local area networks, mobile communication networks, and combinations thereof.

[0072] This application also provides an engineering vehicle, which is equipped with a power shift gearbox and a clutch controller, the clutch controller being used to execute the steps in the method described in any embodiment of this disclosure.

[0073] The embodiments described in this application are for the purpose of more clearly illustrating the technical solutions of the embodiments of this application, and do not constitute a limitation on the technical solutions provided by the embodiments of this application. As those skilled in the art will know, with the evolution of technology and the emergence of new application scenarios, the technical solutions provided by the embodiments of this application are also applicable to similar technical problems.

[0074] Those skilled in the art will understand that the technical solutions shown in the figures do not constitute a limitation on the embodiments of this application, and may include more or fewer steps than shown, or combine certain steps, or different steps.

[0075] The device embodiments described above are merely illustrative. The units described as separate components may or may not be physically separate; that is, they may be located in one place or distributed across multiple network units. Some or all of the modules can be selected to achieve the purpose of this embodiment according to actual needs.

[0076] Those skilled in the art will understand that all or some of the steps in the methods disclosed above, as well as the functional modules / units in the systems and devices, can be implemented as software, firmware, hardware, or suitable combinations thereof.

[0077] The terms “first,” “second,” “third,” “fourth,” etc. (if present) in the specification and accompanying drawings of this application are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of this application described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms “comprising” and “having,” and any variations thereof, are intended to cover non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0078] It should be understood that in this application, "at least one (item)" means one or more, and "more than" means two or more. "And / or" is used to describe the relationship between related objects, indicating that three relationships can exist. For example, "A and / or B" can represent three cases: only A exists, only B exists, and both A and B exist simultaneously, where A and B can be singular or plural. The character " / " generally indicates that the preceding and following related objects are in an "or" relationship. "At least one (item) of the following" or similar expressions refer to any combination of these items, including any combination of single or plural items. For example, at least one (item) of a, b, or c can represent: a, b, c, "a and b", "a and c", "b and c", or "a and b and c", where a, b, and c can be single or multiple.

[0079] In the several embodiments provided in this application, it should be understood that the disclosed apparatus and methods can be implemented in other ways. For example, the apparatus embodiments described above are merely illustrative; for instance, the division of the units described above is only a logical functional division, and in actual implementation, there may be other division methods. For example, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Furthermore, the coupling or direct coupling or communication connection shown or discussed may be through some interfaces; the indirect coupling or communication connection between apparatuses or units may be electrical, mechanical, or other forms.

[0080] The units described above as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the units can be selected to achieve the purpose of this embodiment according to actual needs.

[0081] Furthermore, the functional units in the various embodiments of this application can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. The integrated unit can be implemented in hardware or as a software functional unit.

[0082] If the integrated unit is implemented as a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of this application, in essence, or the part that contributes to the prior art, or all or part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes multiple instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods of the various embodiments of this application. The aforementioned storage medium includes various media capable of storing programs, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

[0083] The preferred embodiments of the present application have been described above with reference to the accompanying drawings, but this does not limit the scope of the claims of the present application. Any modifications, equivalent substitutions, and improvements made by those skilled in the art without departing from the scope and substance of the embodiments of the present application shall be within the scope of the claims of the present application.

Claims

1. A clutch control method for a power shift transmission, characterized in that, The method includes the following steps: In clutch calibration mode, the engine is started at a preset engine speed to determine the target clutch and the opposite clutch, wherein the target clutch and the opposite clutch are in a non-same-end transmission relationship. Control the engagement of the opposing clutch and monitor the current speed difference between the current engine speed and the current transmission input shaft speed; Based on the current speed difference between the engine speed and the gearbox input shaft speed, a slip engagement flag is generated when the target clutch enters a slip engagement state; The initial oil filling time period of the target clutch is determined, and the initial oil filling time period is corrected according to the interval of the slip-friction engagement indicator in the initial oil filling time period of the target clutch to obtain the corrected oil filling time period.

2. The method according to claim 1, characterized in that, The step of generating a slip engagement flag when the target clutch enters a slip engagement state based on the current speed difference between the engine speed and the transmission input shaft speed includes: Determine whether the current speed difference is less than or equal to the preset speed difference. If so, generate the slip-friction engagement flag at the current time step.

3. The method according to claim 1, characterized in that, The oil filling time period includes the fast charging range, the pressure holding range, and the pressure boosting range; The step of correcting the initial oil filling time period based on the location of the slip-and-grip engagement indicator within the initial oil filling time period of the target clutch to obtain the corrected oil filling time period includes: Poll the aforementioned friction engagement indicator; If the slip-fist engagement flag is found within the fast-charging interval of the initial oil filling time period, the fast-charging interval of the initial oil filling time period is reduced by a standard duration to obtain the corrected oil filling time period. Then, the execution steps are returned: control the closing of the opposite clutch and monitor the current speed difference between the current engine speed and the current transmission input shaft speed. If the slip-fist engagement flag is not found within the pressure holding interval of the initial oil filling time period and after the preset pressure holding time upper limit, then the fast charging interval or pressure holding interval of the initial oil filling time period is increased by a standard duration to obtain the corrected oil filling time period, and the execution steps are returned: control the closing of the opposite clutch, and monitor the current speed difference between the current engine speed and the current transmission input shaft speed; If the slip-fist engagement flag is found within the pressure holding range of the initial oil filling time period and before the preset pressure holding time upper limit, then the initial oil filling time period is taken as the corrected oil filling time period, and the clutch calibration mode is exited.

4. The method according to claim 3, characterized in that, If the slip-fitting indicator is not found within the pressure holding interval of the initial oil filling time period and after the preset pressure holding time upper limit, then the fast charging interval or pressure holding interval of the initial oil filling time period will be increased by a standard duration, including: If the pressure holding interval of the initial oil filling time period does not reach the maximum oil filling time limit, then the pressure holding interval of the initial oil filling time period will be increased by a standard duration. If the pressure holding interval of the initial oil filling time period has reached the maximum oil filling time limit, then the fast charging interval of the initial oil filling time period will be increased by a standard duration, and the pressure holding interval will be reset to the initial duration.

5. The method according to any one of claims 3 or 4, characterized in that, The method further includes: After obtaining the corrected oil filling time period, the calibration count is reset to 0, and the execution steps are returned: control the closing of the opposite clutch, and monitor the current speed difference between the current engine speed and the current transmission input shaft speed; After using the initial oil filling time period as the corrected oil filling time period, the calibration count is increased by 1. When the calibration count reaches a preset number, the clutch calibration mode is exited.

6. The method according to claim 1, characterized in that, The method further includes: In response to the command to calibrate the target clutch, the transmission oil temperature, the position of the travel lever, and the vehicle's driving status are acquired; The system determines whether preset operating conditions are met based on the transmission oil temperature, the position of the travel lever, and the vehicle's travel status. If the conditions are met, the system enters the clutch calibration mode; otherwise, an alarm message is sent.

7. A clutch control device for a power shift transmission, characterized in that, The device includes: The starting module is used to start the engine at a preset engine speed in clutch calibration mode, and to determine the target clutch and the opposite clutch, wherein the target clutch and the opposite clutch are in a non-same-end transmission relationship. The speed difference determination module is used to control the closing of the opposite clutch and monitor the current speed difference between the current engine speed and the current transmission input shaft speed. A flag generation module is used to generate a slip engagement flag when the target clutch enters a slip engagement state, based on the current speed difference between the engine speed and the gearbox input shaft speed. The correction module is used to determine the initial oil filling time period of the target clutch, and correct the initial oil filling time period according to the interval of the slip-friction engagement mark in the initial oil filling time period of the target clutch to obtain the corrected oil filling time period.

8. An electronic device, characterized in that, include: At least one processor; At least one memory for storing at least one program; When the at least one program is executed by the at least one processor, the at least one processor implements the method as described in any one of claims 1 to 6.

9. A computer-readable storage medium storing a computer program, characterized in that, When the computer program is executed by a processor, it implements the method described in any one of claims 1 to 6.

10. An engineering vehicle, characterized in that, The engineering vehicle is equipped with a power shift gearbox and a clutch controller, the clutch controller being used to perform the steps of the method according to any one of claims 1 to 6.

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