Clutch control methods, devices, storage media and program products

Abstract

This application relates to a clutch control method, device, storage medium, and program product, belonging to the field of vehicle control technology. The method is implemented in a vehicle equipped with an automatic engine start-stop system, and includes: when the automatic engine start-stop system is operating and the engine is automatically shut off, predicting the engine restart speed based on vehicle operating condition information; determining a first oil pressure based on the engine restart speed; the first oil pressure is used to ensure that the clutch output torque does not exceed a perceptible minimum impact transmission torque; when the automatic engine start-stop system is operating and the engine restarts, controlling the clutch to a semi-engaged state via an electronic pump based on the first oil pressure; acquiring a second oil pressure; the second oil pressure is the oil pressure output by a mechanical pump after the engine restarts; and when the second oil pressure is equal to the first oil pressure, controlling the clutch to a fully engaged state via a mechanical pump. This application can improve the smoothness of the vehicle's movement after it has stopped.

Description

Technical Field

[0001] This application relates to the field of vehicle control technology, and in particular to a clutch control method, device, storage medium, and program product. Background Technology

[0002] When a vehicle temporarily stops during driving (such as waiting at a red light), the engine of a traditional gasoline-powered car can run at its lowest speed. At this time, the vehicle is not moving but will still consume fuel.

[0003] In related technologies, the engine's automatic start-stop function allows the vehicle to automatically shut off when waiting at a red light and automatically restart the engine when moving forward; therefore, the engine's automatic start-stop function can achieve the effects of energy saving, emission reduction, and reduced fuel consumption.

[0004] However, restarting the engine after it automatically shuts off usually involves a shock and vibration throughout the vehicle, which can easily lead to an uncomfortable driving experience for the owner. Summary of the Invention

[0005] This application provides a clutch control method, device, storage medium, and program product, which can improve the vehicle's smoothness when restarting after the engine has automatically shut down. The technical solution is as follows:

[0006] On one hand, a clutch control method is provided, the method being implemented in a vehicle having an engine start-stop system, the method comprising:

[0007] When the engine automatic start-stop system is working and the engine automatically shuts off, the engine restart speed information is predicted based on the vehicle operating condition information; the vehicle operating condition information includes at least the engine status information, and the engine speed information is used to indicate the speed increase process after the engine restarts.

[0008] Based on the upward speed information, a first oil pressure is determined; the first oil pressure is used to ensure that the output torque of the clutch is not greater than the minimum perceptible impact transmission torque.

[0009] When the engine automatic start-stop system is working and the engine is restarted, the clutch is controlled to be in a semi-engaged state by the electronic pump according to the first oil pressure.

[0010] Obtain the second oil pressure; the second oil pressure is the oil pressure output by the mechanical pump after the engine is restarted;

[0011] When the second oil pressure is equal to the first oil pressure, the clutch is controlled to be in a pressed state by the mechanical pump.

[0012] On the one hand, a vehicle control system is provided, the system including an engine control unit and a transmission control unit;

[0013] The engine control unit is used to predict the initial speed information of the engine restart based on vehicle operating condition information when the engine automatic start-stop system is working and the engine automatically shuts off; the vehicle operating condition information includes at least the engine status information, and the initial speed information is used to indicate the speed increase process after the engine restarts.

[0014] The transmission control unit is used to determine a first oil pressure based on the upward speed information; the first oil pressure is used to ensure that the output torque of the clutch is not greater than the minimum perceptible impact transmission torque.

[0015] The transmission control unit is used to control the clutch to a semi-engaged state via the electronic pump based on the first oil pressure when the engine automatic start-stop system is working and the engine is restarted.

[0016] The transmission control unit is used to acquire a second oil pressure; the second oil pressure is the oil pressure output by the mechanical pump after the engine is restarted.

[0017] The transmission control unit is used to control the clutch to be in a pressed state by means of the mechanical pump when the second oil pressure is equal to the first oil pressure.

[0018] On the other hand, a clutch control device is provided, the device comprising:

[0019] The engine speed prediction module is used to predict the initial engine speed information upon restarting the engine when the engine automatic start-stop system is working and the engine is automatically shut off, based on vehicle operating condition information; the vehicle operating condition information includes at least the engine status information, and the initial engine speed information is used to indicate the increase in engine speed after the engine restarts.

[0020] The oil pressure determination module is used to determine a first oil pressure based on the upward stroke speed information; the first oil pressure is used to ensure that the output torque of the clutch is not greater than the minimum perceptible impact transmission torque.

[0021] The first control module is used to control the clutch to a semi-engaged state via the electronic pump based on the first oil pressure when the engine automatic start-stop system is working and the engine is restarted.

[0022] The oil pressure acquisition module is used to acquire a second oil pressure; the second oil pressure is the oil pressure output by the mechanical pump after the engine is restarted.

[0023] The second control module is used to control the clutch to be in a pressed state via the mechanical pump when the second oil pressure is equal to the first oil pressure.

[0024] In one possible implementation, the oil pressure determining module is used to determine the output torque of the clutch based on the upward stroke speed information;

[0025] The oil pressure determination module is used to determine the first oil pressure based on the output torque of the clutch.

[0026] In one possible implementation, the hydraulic pressure determination module is used to acquire a torque difference; the torque difference is used to indicate the difference between the output torque of the clutch and the perceptible minimum impact transmission torque;

[0027] The oil pressure determination module is used to determine the first oil pressure based on the torque difference.

[0028] In one possible implementation, the device further includes:

[0029] An electronic pump starter module is used to start the electronic pump when the engine automatic start-stop system is working and the engine automatically shuts off.

[0030] A mechanical pump starting module is used to start the mechanical pump when the engine automatic start-stop system is working and the engine is restarted.

[0031] An electronic pump shut-off module is used to shut down the electronic pump when the second oil pressure is equal to the first oil pressure.

[0032] In one possible implementation, the engine status information includes the missing tooth position information of the engine and the engine coolant temperature information; the vehicle operating condition information also includes the ambient temperature information of the vehicle, the battery capacity of the vehicle, and the oil temperature information of the transmission.

[0033] In another aspect, a computer device is provided, the computer device comprising a processor and a memory, the memory storing at least one instruction, at least one program, code set or instruction set, the at least one instruction, the at least one program, the code set or instruction set being loaded and executed by the processor to implement the clutch control method as described above.

[0034] In another aspect, a computer-readable storage medium is provided, wherein at least one instruction, at least one program, code set, or instruction set is stored therein, wherein the at least one instruction, the at least one program, the code set, or the instruction set is loaded and executed by a processor to implement the clutch control method described above.

[0035] In another aspect, a computer program product is provided, comprising a computer program stored in a computer-readable storage medium. A processor of a computer device reads the computer program from the computer-readable storage medium and executes the computer program, causing the computer device to perform the clutch control method provided in the various alternative implementations described above.

[0036] The technical solution provided in this application may include the following beneficial effects:

[0037] By analyzing the vehicle's status information during startup and shutdown, the initial RPM surge upon engine restart can be predicted. Then, combined with the vehicle's corresponding minimum perceptible impact torque, the transmission oil pressure can be controlled to maintain the clutch in a semi-engaged state. This prevents the engine restart shock from causing a noticeable lurch to the driver, thus improving the smoothness of the vehicle's movement after a stop. Furthermore, this solution, through the alternating use of electronic and mechanical pumps, avoids significant changes in clutch status due to low oil pressure during engine shutdown. After engine restart, when the oil pressures of the mechanical and electronic pumps are equal, a smooth oil circuit transition can be achieved.

[0038] It should be understood that the above general description and the following detailed description are exemplary and explanatory only, and do not limit this application. Attached Figure Description

[0039] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this application and, together with the description, serve to explain the principles of this application.

[0040] Figure 1 This is a schematic diagram of the implementation environment of the clutch control method provided in an exemplary embodiment of this application;

[0041] Figure 2 This is a flowchart of a clutch control method provided in an exemplary embodiment of this application;

[0042] Figure 3 This is a schematic diagram of engine speed provided in an exemplary embodiment of this application;

[0043] Figure 4 This is a schematic diagram of a starting system for AT / CVT transmission start-stop function provided in an exemplary embodiment of this application;

[0044] Figure 5 This is a block diagram of a clutch control device provided in an exemplary embodiment of this application;

[0045] Figure 6This is a schematic diagram of the structure of a computer device provided in an exemplary embodiment of this application. Detailed Implementation

[0046] To make the objectives, technical solutions, and advantages of this application clearer, the embodiments of this application will be described in further detail below with reference to the accompanying drawings.

[0047] Exemplary embodiments will now be described in detail, examples of which are illustrated in the accompanying drawings. When the following description relates to the drawings, unless otherwise indicated, the same numbers in different drawings denote the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with this application. Rather, they are merely examples of apparatuses and methods consistent with some aspects of this application as detailed in the appended claims.

[0048] The terminology used in this disclosure is for the purpose of describing particular embodiments only and is not intended to be limiting of the disclosure. The singular forms “a,” “the,” and “the” as used in this disclosure and the appended claims are also intended to include the plural forms unless the context clearly indicates otherwise.

[0049] It should be understood that although the terms first, second, etc., may be used in this disclosure to describe various information, such information should not be limited to these terms. These terms are used only to distinguish information of the same type from one another. For example, a first parameter may also be referred to as a second parameter without departing from the scope of this disclosure, and similarly, a second parameter may also be referred to as a first parameter. Depending on the context, the word "if" as used herein may be interpreted as "when," "when," or "in response to determination."

[0050] To facilitate understanding, some concepts involved in this application are explained below.

[0051] 1) Engine Starting: An engine consists of two main mechanisms: the crankshaft and connecting rod mechanism and the valve train; and five major systems: the ignition system, fuel supply system, cooling system, lubrication system, and starting system. Engine starting involves the coordinated operation of multiple components. The battery-powered starting system drives the engine to rotate, the ignition system ignites the fuel at the appropriate time, and the fuel supply system provides the appropriate amount of fuel, enabling the engine to transition from a stationary state to a normal operating state, completing the starting process. The conditions for engine starting include:

[0052] ① Sufficient battery power: The battery needs to have enough power to supply power to the starter motor;

[0053] ② The starting system is working properly: The starter motor of the starting system needs to be working properly to provide sufficient torque to turn the engine;

[0054] ③ Ignition system is normal: The ignition system needs to be able to generate enough sparks to ignite the air-fuel mixture;

[0055] ④ The fuel supply system is functioning normally: The fuel supply system needs to be able to provide an appropriate amount of fuel to the cylinder;

[0056] ⑤ The engine temperature is suitable: In low-temperature conditions, additional preheating measures may be required to help the engine start.

[0057] 2) Engine Stop & Start (STT): STT technology is an automotive technology designed to improve fuel economy and reduce emissions. It allows the vehicle to automatically shut off the engine when temporarily stopped (such as at a red light or in traffic jams) and quickly restart the engine when driving resumes. Therefore, STT technology is suitable for urban driving conditions and is an auxiliary fuel-saving method.

[0058] STT technology integrates a boosted motor with idle start-stop function into the engine, so that when the vehicle meets the conditions for idling, the engine is completely shut off and does not work; when the vehicle needs to be started again, the idle start-stop motor system containing the boosted motor can quickly respond to the user's start command, start the engine quickly, and connect instantly, thereby reducing fuel consumption and exhaust emissions.

[0059] 3) Transmission: Also known as a gearbox, it is an important component of a vehicle's transmission system, capable of changing the engine's output torque and speed to adapt to different driving conditions. Based on the transmission method, transmissions can be divided into manual transmissions and automatic transmissions. The technical solution of this application applies to automatic transmissions with hydraulic torque converters, such as automatic transmissions (AT) and continuously variable transmissions (CVT).

[0060] 4) Torque Converter: Also known as a "turbo torque converter" or "hydrodynamic torque converter," it transmits torque through a fluid (such as transmission fluid) and provides torque gain and smooth shifting. A torque converter consists of a pump impeller, a turbine, and a stator. The pump impeller is connected to the engine; when the engine is running, the pump impeller rotates, pushing fluid towards the turbine. The turbine is connected to the transmission input shaft; as fluid flows from the pump impeller to the turbine, the turbine rotates, transmitting torque to the transmission. The stator is located between the pump impeller and the turbine and is equipped with a one-way clutch. The stator increases the turbine's output torque, and the one-way clutch ensures that the stator rotates only in one direction, preventing fluid from returning directly from the turbine to the pump impeller.

[0061] 5) The three states of the clutch:

[0062] ①Disengaged state: In the disengaged state, the clutch is completely disengaged, there is no torque transmission between the engine and the transmission system, and even if the engine is running, it will not drive the wheels to rotate;

[0063] ② Semi-clutch state: In the semi-clutch state, the clutch is partially engaged, and there is a certain torque transmission between the engine and the transmission system;

[0064] ③ Tightened state: In the tightened state, the clutch is fully engaged, and the torque can be maximized between the engine and the transmission system.

[0065] Please refer to Figure 1 This diagram illustrates an implementation environment for a clutch control method provided in an exemplary embodiment of this application. Figure 1 As shown, the implementation environment may include: a vehicle with an automatic engine start-stop system, the vehicle including a vehicle control system 110 and multiple vehicle mechanical structures 120.

[0066] The vehicle control system 110 may include a central control unit of the vehicle and sub-control units (such as electronic control units, ECUs) connected to the central control unit bus. These sub-control units may include, but are not limited to, one or more of the following: engine control unit 110a and transmission control unit 110b.

[0067] The aforementioned vehicle mechanical devices 120 are controlled by the vehicle control system 110. The vehicle mechanical devices 120 may include, but are not limited to, one or more of the following: engine 120a, transmission 120b.

[0068] The engine 120a is controlled by the engine control unit 110a, and the gearbox 120b is controlled by the gearbox control unit 110b. The gearbox 120b may include, but is not limited to, one or more of the following: a hydraulic torque converter 120b1, a mechanical pump 120b2, an electronic pump 120b3, and a clutch 120b4.

[0069] For example, in Figure 1In the system shown, when the engine start-stop system is operating and the engine automatically shuts off, the engine control unit 110a can predict the engine restart speed based on vehicle operating condition information. This vehicle operating condition information includes at least engine status information, and the engine restart speed information indicates the speed increase process after engine restart. The engine control unit 110a can then send the predicted engine restart speed information to the bus. Correspondingly, the transmission control unit 110b can obtain this engine restart speed information from the bus. Based on the engine restart speed information, the transmission control unit 110b can determine a first oil pressure. This first oil pressure ensures that the clutch output torque is not greater than the minimum perceptible impact transmission torque. When the engine start-stop system is operating and the engine restarts, the transmission control unit 110b controls the clutch to a semi-engaged state via an electronic pump based on the first oil pressure. Then, the transmission control unit 110b obtains a second oil pressure, which is the oil pressure output by the mechanical pump after engine restart. When the second oil pressure is equal to the first oil pressure, the transmission control unit 110b controls the clutch to a fully engaged state via the mechanical pump.

[0070] Please refer to Figure 2 The diagram illustrates a flowchart of a clutch control method provided in an exemplary embodiment of this application. This method is implemented in a vehicle equipped with an engine automatic start-stop (STT) system and can be executed by the vehicle's vehicle control system. Optionally, the vehicle may be... Figure 1 The vehicles in the system shown. For example... Figure 2 As shown, the method may include steps 210, 220, 230, 240 and 250.

[0071] Step 210: When the engine automatic start-stop system is working and the engine automatically shuts off, predict the engine restart speed information based on the vehicle operating condition information; the vehicle operating condition information includes at least the engine status information, and the engine restart speed information is used to indicate the speed increase process after the engine restarts.

[0072] The aforementioned operation of the engine automatic start-stop system refers to the vehicle's engine automatic start-stop (STT) system being in normal working order and not being shut down. During the engine restart process, the first half of the starter motor speed increase relies on the starter motor's drag, while the second half relies on the engine's own power output. For example, as... Figure 3 As shown, 0.1 seconds after the engine restarts, at a speed of 120 Rps, the engine speed begins to rise until it reaches a maximum speed of 1400 Rps.

[0073] For example, when the engine start-stop system is operating and the engine automatically shuts off, the engine control unit in the vehicle control system can collect the aforementioned vehicle operating condition information through various sensors on the vehicle. These sensors include, but are not limited to, one or more of the following: engine temperature sensor, coolant temperature sensor, battery voltage sensor, and ambient temperature sensor.

[0074] Developers can pre-set the prediction method for the aforementioned engine speed surge information, enabling the vehicle control system to predict the surge speed information based on this method. For example, predicting the engine speed surge information upon restarting based on vehicle operating condition information can be achieved by: searching for the surge speed information corresponding to the vehicle operating condition information in the surge speed table; where the surge speed table can indicate the correspondence between engine model, vehicle operating condition information, and surge speed information.

[0075] For example, the above-mentioned prediction of the engine restart speed based on vehicle operating condition information can also be implemented by inputting the vehicle operating condition information into a pre-set calculation formula to calculate the corresponding engine restart speed information.

[0076] For example, the above-mentioned prediction of the engine restart speed information based on vehicle operating condition information can also be implemented as follows: inputting the vehicle operating condition information into the speed prediction model to obtain the speed prediction model outputting the speed restart speed information; wherein, the speed prediction model is a machine learning model trained by vehicle operating condition information samples and corresponding speed restart speed information samples.

[0077] It should be noted that when the engine start-stop system is working and the engine automatically shuts off, the transmission control unit in the vehicle control system can control the electronic pump to start working, and the oil pressure corresponding to the electronic pump can be precisely controlled by the transmission control unit.

[0078] Step 220: Determine the first oil pressure based on the upward stroke speed information; the first oil pressure is used to ensure that the output torque of the clutch is not greater than the minimum perceptible impact transmission torque.

[0079] It should be noted that the engine output torque varies at different engine speeds. In this embodiment, the transmission control unit can predict the increase in torque transmitted to the transmission input shaft after the engine restarts based on the acceleration speed information.

[0080] For example, after obtaining the aforementioned surge speed information, the engine control unit can send the surge speed information to the bus, and the transmission control unit can obtain the surge speed information from the bus and determine the first oil pressure based on the surge speed information.

[0081] The first oil pressure mentioned above refers to the pressure of the transmission fluid in the transmission, which is transmitted to the clutch, causing the clutch to be in one of the following states: disengaged, partially engaged, or engaged.

[0082] In this embodiment, the transmission control unit can obtain the torque transmitted to the clutch output terminal based on the output torque information. If the torque transmitted to the clutch output terminal is less than or equal to the minimum perceptible impact transmission torque, the first oil pressure can be a larger value; if the torque transmitted to the clutch output terminal is greater than the minimum perceptible impact transmission torque, the first oil pressure can be a smaller value, so that the clutch output torque is not greater than the minimum perceptible impact transmission torque.

[0083] The aforementioned minimum perceptible impact torque indicates the maximum allowable torque during engine startup. Exceeding this minimum perceptible impact torque may cause the driver and passengers to experience a noticeable impact or vibration. For example, this minimum perceptible impact torque can be determined by developers through multiple tests; specifically, developers can set multiple clutch output torque test values ​​for the same vehicle model and transmission system, and test the impact force of each clutch's output torque on the vehicle to determine the minimum perceptible impact torque for the driver and passengers.

[0084] For example, developers can determine the correspondence between different vehicle models, different transmission systems and the perceived minimum impact transmission torque based on multiple tests of different vehicle models and different transmission systems; correspondingly, the transmission control unit can determine the corresponding perceived minimum impact transmission torque based on the current vehicle model and transmission system.

[0085] Step 230: When the engine start-stop system is working and the engine is restarted, the clutch is controlled to be in a semi-engaged state by the electronic pump according to the first oil pressure.

[0086] In other words, when the engine is restarted, the transmission control unit of the vehicle control system can set the oil pressure of the electronic pump to the first oil pressure to provide pressure to the clutch, so that the clutch is in a semi-engaged state.

[0087] When the clutch is in a semi-engaged state, the torque from the engine output shaft will not be fully transmitted to the transmission system.

[0088] Step 240: Obtain the second oil pressure; the second oil pressure is the oil pressure output by the mechanical pump after the engine is restarted.

[0089] When the engine automatic start-stop system is working and the engine restarts, the engine can drive the mechanical pump to start working and build up oil pressure.

[0090] In this embodiment of the application, the transmission control unit of the vehicle control system can obtain the second oil pressure corresponding to the mechanical pump through the oil pressure sensor of the mechanical pump.

[0091] Step 250: When the second oil pressure is equal to the first oil pressure, the clutch is controlled to be in a pressed state by the mechanical pump.

[0092] The statement that the second oil pressure is equal to the first oil pressure means that the second oil pressure established by the mechanical pump gradually increases and reaches the first oil pressure corresponding to the electronic pump. At this time, the transmission control unit of the vehicle control system can reverse the oil circuit through the solenoid valve, so that the mechanical pump provides oil pressure to the clutch and shuts off the electronic pump; as the oil pressure corresponding to the mechanical pump further increases, the clutch is in a engaged state, and the vehicle completes the steady starting process.

[0093] In summary, the solution presented in this application, by utilizing the vehicle's state information during engine start-up and shutdown, can predict the initial RPM surge during engine restart. Then, by combining this with the vehicle's corresponding minimum perceptible impact torque, the transmission oil pressure can be controlled, keeping the clutch in a semi-engaged state. This prevents the impact force during engine restart from causing a noticeable lurching sensation for the driver, thereby improving the smoothness of the vehicle's movement after stopping. Furthermore, this solution, through the alternating use of electronic and mechanical pumps, avoids significant changes in clutch state due to low oil pressure during engine shutdown. After engine restart, when the oil pressures of the mechanical and electronic pumps are equal, a smooth switching of the oil circuit can be achieved.

[0094] Based on the above Figure 2 In one possible implementation of the scheme shown in the embodiment, step 220 can be implemented as follows:

[0095] Step 220a: Determine the output torque of the clutch based on the upward stroke speed information.

[0096] It should be noted that the output torque of an engine varies with its speed. Consequently, the torque transmitted from the engine to the transmission input shaft, after being transmitted through the torque converter and consumed by the mechanical pump, will ultimately be different when it reaches the clutch output shaft.

[0097] The output torque of the aforementioned clutch corresponds to the torque that can be transmitted to the wheels after the engine starts.

[0098] For example, the transmission control unit can determine the engine output torque corresponding to the maximum surge speed based on the engine's surge speed information; then, based on the torque loss of the pump impeller and turbine of the torque converter during hydraulic transmission, and the torque consumed by the mechanical pump to establish oil pressure, it can determine the torque transmitted to the clutch output shaft. For instance, the transmission control unit can use the engine output torque minus the torque loss of the torque converter and the torque consumed by the mechanical pump as the clutch output shaft torque.

[0099] For example, the engine output torque corresponding to the maximum upward speed mentioned above can be calculated using the following formula:

[0100]

[0101] Where T is the engine's output torque (unit: Newton-meters Nm), P is the engine's power (unit: kilowatts kW), and N is the engine's maximum up-thrust speed (unit: speeds per second Rps).

[0102] For example, the engine output torque corresponding to the maximum upward speed mentioned above can also be read from the engine's torque-speed curve. This torque-speed curve can be pre-set by the developers to display the engine's output torque at different speeds.

[0103] Step 220b: Determine the first oil pressure based on the output torque of the clutch.

[0104] In this embodiment, the transmission control unit can determine a reasonable first oil pressure based on the obtained output torque of the clutch. This first oil pressure is used to make the output torque of the clutch less than or equal to the minimum perceptible impact transmission torque.

[0105] This application provides a feasible solution for determining the first oil pressure based on the upward stroke speed information, which fully considers the transmission of the hydraulic torque converter and the consumption of the mechanical pump, and can improve the accuracy of the first oil pressure.

[0106] Based on the solutions shown in the above embodiments of this application, in one possible implementation, step 220b can be implemented as follows:

[0107] Obtain the torque difference; the torque difference is used to indicate the difference between the clutch's output torque and the minimum perceptible impact transmission torque;

[0108] The first oil pressure is determined based on the torque difference.

[0109] The torque difference mentioned above can be the difference between the clutch output torque and the minimum perceptible impact transmission torque. When the difference is negative or zero, it means that the driver and passengers will not feel any obvious impact or vibration. In this case, the first oil pressure can be a larger oil pressure value. When the difference is positive, it means that the driver and passengers can feel obvious impact or vibration. In this case, the first oil pressure can be a smaller oil pressure value.

[0110] For example, developers can pre-set a lookup table between torque difference and first oil pressure and store the lookup table in the transmission control unit; accordingly, the transmission control unit can look up the first oil pressure corresponding to the current torque difference in the lookup table.

[0111] In this embodiment, the transmission control unit can determine the first oil pressure that meets the conditions by comparing the output torque of the clutch and the magnitude of the minimum perceptible impact transmission torque, so that the driver and passengers will not feel obvious impact or vibration, thereby improving the smoothness of the engine starting process.

[0112] Based on the solutions shown in the above embodiments of this application, in one possible implementation, the clutch control method further includes the following steps:

[0113] When the engine start-stop system is working and the engine automatically shuts off, the electric pump is activated.

[0114] When the engine automatic start-stop system is working and the engine is restarted, the mechanical pump is activated.

[0115] When the second oil pressure is equal to the first oil pressure, turn off the electronic pump.

[0116] In this embodiment of the application, when the engine automatically shuts off, the mechanical pump automatically stops working. At this time, in order to ensure lubrication and cooling inside the transmission, the transmission control unit can start the electronic pump to maintain the necessary oil pressure.

[0117] When the engine restarts, the mechanical pump starts working to build up oil pressure, while the electric pump continues to operate. When the second oil pressure built up by the mechanical pump reaches the first oil pressure maintained by the electric pump, the oil pressure of the mechanical and electric pumps reaches equilibrium. After the solenoid valve completes the oil circuit reversal, the transmission control unit can shut down the electric pump, and the mechanical pump continues to supply oil pressure.

[0118] This application provides the start-stop timing for the electronic pump and the mechanical pump, specifically including: when the engine automatically shuts off, the mechanical pump stops working and the electronic pump starts; when the engine restarts, the mechanical pump starts and builds up oil pressure; when the oil pressure of the mechanical pump reaches the oil pressure of the electronic pump, the oil circuit is switched via a solenoid valve, i.e., the oil circuit is switched from the electronic pump to the mechanical pump, and the electronic pump is shut off. This solution, through the alternating use of the electronic and mechanical pumps, avoids significant changes in the clutch state due to excessively low oil pressure during engine shutdown; and after the engine restarts, when the oil pressures of the mechanical and electronic pumps are equal, a smooth switching of the oil circuit can be achieved.

[0119] Based on the solutions shown in the above embodiments of this application, in one possible implementation, the engine status information indication includes the engine tooth missing position information and the engine coolant temperature information; the vehicle operating condition information also includes the ambient temperature information of the vehicle, the vehicle battery capacity, and the transmission oil temperature information.

[0120] The missing tooth position information of the engine mentioned above is used to indicate one or more missing tooth positions on the engine crankshaft signal disc (also known as the signal gear ring or signal wheel). This missing tooth position helps the engine control unit determine the position of the engine crankshaft, and thus determine the various working cycles of the engine. For example, this missing tooth position can assist the engine control unit in determining ignition and fuel injection timing to ensure that the engine ignites and injects fuel at the correct time. For example, the engine control unit can obtain the missing tooth position information through a speed sensor and phase relationship; where the phase relationship refers to the engine valve timing, that is, the angle of the opening and closing of the intake and exhaust valves relative to the crankshaft position.

[0121] The engine coolant temperature information mentioned above indicates the temperature of the engine coolant, reflects the overall thermal state of the engine, and can affect the engine's starting performance. When the engine is stopped, the coolant temperature gradually drops to ambient temperature. For example, the engine control unit can obtain the engine coolant temperature information through a coolant temperature sensor.

[0122] The ambient temperature information of the vehicle indicates the temperature around the vehicle, which can affect the viscosity of the engine oil and the fluidity of the coolant, thereby affecting the calibration of the fuel evaporation and injection system. For example, the engine control unit can obtain the ambient temperature information of the vehicle through the vehicle's temperature sensors.

[0123] The battery capacity information of the aforementioned vehicle indicates the remaining battery capacity and can affect the starter motor's efficiency. When the engine is off, if the vehicle's electrical loads (such as lights and audio systems) continue to consume power, the battery capacity will gradually decrease. For example, the engine control unit can obtain the vehicle's battery capacity information through the corresponding battery charge sensor.

[0124] The aforementioned transmission fluid temperature information indicates the temperature of the transmission fluid within the transmission, which can affect engine starting efficiency. For example, the transmission control unit can obtain the transmission fluid temperature information via a transmission fluid temperature sensor and send this information to the bus, from which the engine control unit can obtain the transmission fluid temperature information.

[0125] In one possible implementation, the engine control unit can set a base engine speed based on the missing gear position when the engine stops. Then, if the engine coolant temperature, ambient temperature, battery capacity, and transmission fluid temperature are low, the engine control unit can increase the surge speed; conversely, if these conditions are high, the engine control unit can decrease the surge speed. Subsequently, the engine control unit can predict the ignition timing and injection timing based on the missing gear position when the engine stops, and thus predict the surge speed.

[0126] This application embodiment provides the specific content that the above-mentioned vehicle operating condition information may include. The engine control unit in the vehicle control system can comprehensively consider information such as the missing tooth position, ambient temperature, coolant, and battery capacity at the moment of engine shutdown, and predict the initial speed when the engine restarts, so as to ensure that the engine can start quickly and improve the engine starting performance.

[0127] This application also provides a vehicle control system, which can be Figure 1 The system shown includes a vehicle control system 110. This system comprises an engine control unit and a transmission control unit.

[0128] The engine control unit is used to predict the initial speed information for engine restart based on vehicle operating condition information when the engine automatic start-stop system is working and the engine is automatically shut off; the vehicle operating condition information includes at least engine status information, and the initial speed information is used to indicate the speed increase process after the engine restarts.

[0129] The transmission control unit is used to determine the first oil pressure based on the upward stroke speed information; the first oil pressure is used to ensure that the output torque of the clutch is not greater than the minimum perceptible impact transmission torque.

[0130] The transmission control unit is used to control the clutch to a semi-engaged state via an electronic pump based on the first oil pressure when the engine start-stop system is working and the engine is restarted.

[0131] The transmission control unit is used to obtain the second oil pressure; the second oil pressure is the oil pressure output by the mechanical pump after the engine is restarted.

[0132] The transmission control unit is used to control the clutch to be in a pressed state via a mechanical pump when the second oil pressure is equal to the first oil pressure.

[0133] The specific methods by which the vehicle control system, engine control unit, and transmission control unit perform operations in the above embodiments have been described in detail in the embodiments related to the method, and will not be elaborated here.

[0134] The clutch control method described in the above embodiments of this application can be applied to traditional automatic transmissions with hydraulic torque converters. In related technologies, when the start-stop function is enabled and the engine is restarted after a shutdown, the engine start-up can easily cause a jolt in the vehicle. To address this jolt problem, based on any one or more of the above embodiments, this application proposes a control method for starting the start-stop function of an AT / CVT transmission. First, based on the operating condition information after shutdown, the target engine ignition speed is obtained. Based on the target speed, the speed of the transmission input shaft is monitored. When the input shaft speed exceeds a certain value, clutch engagement control is performed. This application precisely controls the clutch pressure during the start-up process, maintaining it in a semi-engaged state. This prevents the engine start-up shock from being transmitted to the transmission system through the hydraulic torque converter and clutch, significantly reducing the impact on the transmission system during engine start-up and reducing the jerkiness of the vehicle during startup.

[0135] The structure corresponding to the above control method is as follows Figure 4 As shown, the engine's output shaft is connected to the input shaft of the torque converter, which in turn is connected to a mechanical pump. After the engine starts, it drives the torque converter and the mechanical pump. A solenoid valve is located in the main oil circuit of the transmission, allowing switching between an electronic pump and a mechanical pump supplying oil pressure to the clutch. The aforementioned control methods involve engine start-up speed control, torque converter clutch control, electronic oil pump control, solenoid valve oil pressure and steering valve control, clutch control, etc. A detailed description of the specific process is as follows:

[0136] 1) After the engine stops, based on the current stop position, estimate the starting time and starting acceleration speed, and use this as the target time and target speed for the next start, then input it to the transmission controller:

[0137] When the engine stops, the engine control unit estimates the engine's starting speed and starting time based on information such as the missing tooth position, phase relationship, ambient temperature, water temperature, and battery capacity at the moment the engine stops. This information is then transmitted to the transmission control unit via the vehicle network as the target starting speed and target time.

[0138] 2) When the engine starts, the transmission control unit, based on the estimated engine start time and initial speed, controls the electronic start-stop pump to provide a preset first-gear clutch pressure:

[0139] Based on the aforementioned target starting speed and target time, the transmission control unit estimates the engine output torque increase process. Specifically, according to the characteristics of the torque converter, during the upward stroke of the engine driving the input shaft of the torque converter, the torque loss of the turbine and pump impeller in the hydraulic transmission process, the torque consumed by the mechanical pump pressure build-up, etc., are ultimately transmitted to the clutch end through the output shaft of the torque converter.

[0140] Next, the torque transmitted from the output shaft of the hydraulic torque converter is subtracted from the perceptible minimum impact transmission torque to obtain a difference. This perceptible minimum impact transmission torque is pre-determined by the developers through trials and tests for different vehicle models and transmission systems.

[0141] When the above difference is negative or zero, the electronic pump provides a first numerical oil pressure; the first numerical oil pressure can be a larger pressure value in the pressure range supported by the electronic pump; when the above difference is positive, the electronic pump controls a diaphragm pressure through a second numerical oil pressure according to the difference, so that the torque transmitted through the output shaft of the hydraulic torque converter, after passing through the diaphragm of the clutch, is transmitted to the rear end of the clutch with a torque not greater than the above minimum impact transmission torque.

[0142] 3) During the engine's initial surge and the process of establishing oil pressure with the mechanical pump, the transmission control unit controls the reversing valve inside the solenoid valve to achieve oil pressure reversal from the electronic pump to the mechanical pump:

[0143] During engine up-thrust, the maximum value of the aforementioned budgeted start-up speed is set as the target engine up-thrust speed. Based on the target engine up-thrust speed, the transmission control unit drives the mechanical oil pump to build up transmission oil pressure. When the oil pressure reaches the level provided by the electronic pump, it controls the internal reversing valve of the solenoid valve to move and reverse, ensuring a smooth transition from the electronic pump providing first-gear clutch pressure to the mechanical pump providing first-gear clutch pressure.

[0144] 4) During the solenoid valve reversal process, the pressure of the first gear clutch is precisely controlled. During the engine speed surge, the first gear clutch is in a slippery state. Once the engine speed exceeds the predicted surge speed, the clutch is engaged.

[0145] During the process of the mechanical pump speed increasing in line with the input shaft speed, the switching part of the solenoid valve is pre-charged with oil pressure to ensure smooth and rapid switching.

[0146] The first gear clutch is controlled by a sliding diaphragm. After the engine speed exceeds or reaches the maximum upward speed, the oil pressure of the first gear clutch is controlled to press and engage the first gear clutch, ensuring smooth vehicle start-up response.

[0147] In other words, during engine startup, when the driver accelerates to start, the clutch engagement pressure is calculated based on the initial RPM, and the clutch is controlled with a certain slippage. Once the oil pressure built up by the mechanical pump exceeds this engagement pressure, the system switches to the main oil pressure of the mechanical pump via the solenoid valve's reversing valve, and the clutch clamping oil pressure is increased under the control of the solenoid valve. In summary, this method can significantly reduce the impact on the transmission system when the vehicle is restarted after engine shutdown, thereby reducing the lurching sensation during startup.

[0148] Please refer to Figure 5 The diagram illustrates a block diagram of a clutch control device provided in an exemplary embodiment of this application. This clutch control device can be implemented as all or part of a computer device through hardware or a combination of hardware and software to achieve the above-described... Figure 2 All or part of the steps in the illustrated embodiments. For example... Figure 5 As shown, the device includes:

[0149] The speed prediction module 501 is used to predict the initial speed information of the engine restart when the engine automatic start-stop system is working and the engine is automatically shut off, based on the vehicle operating condition information; the vehicle operating condition information includes at least the engine status information, and the initial speed information is used to indicate the speed increase process after the engine restarts.

[0150] The oil pressure determination module 502 is used to determine the first oil pressure based on the upward stroke speed information; the first oil pressure is used to ensure that the output torque of the clutch is not greater than the minimum perceptible impact transmission torque.

[0151] The first control module 503 is used to control the clutch to a semi-engaged state by an electronic pump based on the first oil pressure when the engine automatic start-stop system is working and the engine is restarted.

[0152] The oil pressure acquisition module 504 is used to acquire the second oil pressure; the second oil pressure is the oil pressure output by the mechanical pump after the engine is restarted.

[0153] The second control module 505 is used to control the clutch to be in a pressed state by means of a mechanical pump when the second oil pressure is equal to the first oil pressure.

[0154] In one possible implementation, the oil pressure determination module 502 is used to determine the output torque of the clutch based on the upward stroke speed information;

[0155] The oil pressure determination module 502 is used to determine the first oil pressure based on the output torque of the clutch.

[0156] In one possible implementation, the hydraulic pressure determination module 502 is used to acquire a torque difference; the torque difference is used to indicate the difference between the clutch output torque and the perceptible minimum impact transmission torque.

[0157] The oil pressure determination module 502 is used to determine the first oil pressure based on the torque difference.

[0158] In one possible implementation, the device further includes:

[0159] The electronic pump starter module is used to start the electronic pump when the engine automatic start-stop system is working and the engine automatically shuts off.

[0160] The mechanical pump starting module is used to start the mechanical pump when the engine automatic start-stop system is working and the engine is restarted.

[0161] The electronic pump shut-off module is used to shut off the electronic pump when the second oil pressure is equal to the first oil pressure.

[0162] In one possible implementation, the engine status information includes the engine tooth gap location information and the engine coolant temperature information; the vehicle operating condition information also includes the ambient temperature of the vehicle, the vehicle's battery capacity, and the transmission oil temperature information.

[0163] It should be noted that the device provided in the above embodiments is only illustrated by the division of the above functional modules when implementing its functions. In actual applications, the above functions can be assigned to different functional modules according to actual needs, that is, the content structure of the device can be divided into different functional modules to complete all or part of the functions described above.

[0164] Regarding the apparatus in the above embodiments, the specific manner in which each module performs its operation has been described in detail in the embodiments of the relevant method; the technical effects achieved by each module performing its operation are the same as the technical effects in the embodiments of the relevant method, and will not be elaborated here.

[0165] Please refer to Figure 6This illustration shows a schematic diagram of the structure of a computer device provided in an exemplary embodiment of this application. The computer device 600 includes a Central Processing Unit (CPU) 601, a system memory 604 including Random Access Memory (RAM) 602 and Read-Only Memory (ROM) 603, and a system bus 605 connecting the system memory 604 and the CPU 601. The computer device 600 also includes a Basic Input / Output System (I / O System) 606 that facilitates information transfer between various devices within the computer, and a mass storage device 607 for storing the operating system 613, application programs 614, and other program modules 615.

[0166] The basic input / output system 606 includes a display 608 for displaying information and an input device 609 for user input, such as a mouse or keyboard. Both the display 608 and the input device 609 are connected to the central processing unit 601 via an input / output controller 610 connected to the system bus 605. The basic input / output system 606 may also include the input / output controller 610 for receiving and processing input from multiple other devices such as a keyboard, mouse, or electronic stylus. Similarly, the input / output controller 610 also provides output to a display screen, printer, or other types of output devices.

[0167] Mass storage device 607 is connected to central processing unit 601 via a mass storage controller (not shown) connected to system bus 605. Mass storage device 607 and its associated computer-readable media provide non-volatile storage for computer device 600. That is, mass storage device 607 may include computer-readable media (not shown) such as hard disk or CD-ROM (Compact Disc Read-Only Memory) drive.

[0168] Without loss of generality, computer-readable media can include computer storage media and communication media. Computer storage media includes volatile and non-volatile, removable and non-removable media implemented using any method or technology for storing information such as computer-readable instructions, data structures, program modules, or other data. Computer storage media include RAM (Random Access Memory), ROM (Read-Only Memory), EPROM (Erasable Programmable Read-Only Memory), EEPROM (Electrically Erasable Programmable Read-Only Memory), flash memory or other solid-state storage technologies, CD-ROM, DVD (Digital Video Disc) or other optical storage, magnetic tape cassettes, magnetic tape, disk storage, or other magnetic storage devices. Of course, those skilled in the art will recognize that computer storage media are not limited to the above-mentioned types. The system memory 604 and mass storage device 607 described above can be collectively referred to as memory.

[0169] Computer device 600 can be connected to the Internet or other network devices via network interface unit 611 connected to system bus 605.

[0170] The memory also includes one or more programs, which are stored in the memory. The central processing unit 601 implements these programs by executing them. Figure 2 All or some of the steps in the method shown.

[0171] In an exemplary embodiment, a chip is also provided, the chip including programmable logic circuitry and / or program instructions, which, when the chip is run on a computer device, are used to implement all or part of the steps of the methods shown in the above embodiments of this application.

[0172] In an exemplary embodiment, a computer program product is also provided, comprising computer instructions stored in a computer-readable storage medium. A processor of a computer device reads the computer instructions from the computer-readable storage medium and executes the computer instructions to implement all or part of the steps of the methods shown in the above embodiments of this application.

[0173] In an exemplary embodiment, a computer-readable storage medium is also provided, which stores a computer program that is loaded and executed by a processor to implement all or part of the steps of the methods shown in the above embodiments of this application.

[0174] Those skilled in the art will understand that all or part of the steps of the above embodiments can be implemented by hardware or by a program instructing related hardware. The program can be stored in a computer-readable storage medium, such as a read-only memory, a disk, or an optical disk.

[0175] Those skilled in the art will recognize that the functions described in the embodiments of this application in one or more of the above examples can be implemented using hardware, software, firmware, or any combination thereof. When implemented using software, these functions can be stored in a computer-readable medium or transmitted as one or more instructions or code on a computer-readable medium. Computer-readable media include computer storage media and communication media, wherein communication media include any medium that facilitates the transfer of a computer program from one place to another. Storage media can be any available medium that can be accessed by a general-purpose or special-purpose computer.

[0176] The above are merely optional embodiments of this application and are not intended to limit this application. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A clutch control method, characterized in that, The method is implemented in a vehicle with an automatic engine start-stop system, and the method includes: When the engine automatic start-stop system is working and the engine automatically shuts off, the engine restart speed information is predicted based on the vehicle operating condition information; the vehicle operating condition information includes at least the engine status information, and the engine speed information is used to indicate the speed increase process after the engine restarts. Based on the upward speed information, a first oil pressure is determined; the first oil pressure is used to ensure that the output torque of the clutch is not greater than the minimum perceptible impact transmission torque. When the engine automatic start-stop system is working and the engine is restarted, the clutch is controlled to be in a semi-engaged state by an electronic pump based on the first oil pressure. Obtain the second oil pressure; the second oil pressure is the oil pressure output by the mechanical pump after the engine is restarted; When the second oil pressure is equal to the first oil pressure, the clutch is controlled to be in a pressed state by the mechanical pump.

2. The method according to claim 1, characterized in that, Determining the first oil pressure based on the upward stroke speed information includes: The output torque of the clutch is determined based on the upward stroke speed information; The first oil pressure is determined based on the output torque of the clutch.

3. The method according to claim 2, characterized in that, Determining the first oil pressure based on the output torque of the clutch includes: Obtain the torque difference; the torque difference is used to indicate the difference between the output torque of the clutch and the perceived minimum impact transmission torque; The first oil pressure is determined based on the torque difference.

4. The method according to any one of claims 1 to 3, characterized in that, The method further includes: When the engine automatic start-stop system is working and the engine automatically shuts off, the electronic pump is started. When the engine automatic start-stop system is working and the engine restarts, the mechanical pump is activated; When the second oil pressure is equal to the first oil pressure, the electronic pump is turned off.

5. The method according to any one of claims 1 to 3, characterized in that, The engine status information includes the missing tooth location information and the engine coolant temperature information; the vehicle operating condition information also includes the ambient temperature information of the vehicle, the battery capacity of the vehicle, and the transmission oil temperature information.

6. A vehicle control system, characterized in that, The system includes an engine control unit and a transmission control unit; The engine control unit is used to predict the engine restart speed information based on vehicle operating condition information when the engine automatic start-stop system is working and the engine is automatically shut off. The vehicle operating condition information includes at least the engine status information, and the surge speed information is used to indicate the speed increase process after the engine restarts; The transmission control unit is used to determine a first oil pressure based on the upward speed information; the first oil pressure is used to ensure that the output torque of the clutch is not greater than the minimum perceptible impact transmission torque. The transmission control unit is used to control the clutch to a semi-engaged state via an electronic pump based on the first oil pressure when the engine automatic start-stop system is working and the engine is restarted. The transmission control unit is used to acquire a second oil pressure; the second oil pressure is the oil pressure output by the mechanical pump after the engine is restarted. The transmission control unit is used to control the clutch to be in a pressed state by means of the mechanical pump when the second oil pressure is equal to the first oil pressure.

7. A clutch control device, characterized in that, The device includes: The engine speed prediction module is used to predict the initial engine speed information when the engine automatic start-stop system is working and the engine is automatically shut off, based on the vehicle operating condition information; the vehicle operating condition information includes at least the engine status information, and the initial engine speed information is used to indicate the increase in engine speed after the engine restarts. The oil pressure determination module is used to determine a first oil pressure based on the upward stroke speed information; the first oil pressure is used to ensure that the output torque of the clutch is not greater than the minimum perceptible impact transmission torque. The first control module is used to control the clutch to a semi-engaged state via an electronic pump based on the first oil pressure when the engine automatic start-stop system is working and the engine is restarted. The oil pressure acquisition module is used to acquire a second oil pressure; the second oil pressure is the oil pressure output by the mechanical pump after the engine is restarted. The second control module is used to control the clutch to be in a pressed state via the mechanical pump when the second oil pressure is equal to the first oil pressure.

8. A computer device, characterized in that, The computer device includes a processor and a memory, the memory storing at least one computer instruction, which is loaded and executed by the processor to implement the clutch control method as described in any one of claims 1 to 5.

9. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores at least one computer instruction, which is loaded and executed by a processor to implement the clutch control method as described in any one of claims 1 to 5.

10. A computer program product, characterized in that, The computer program product includes computer instructions stored in a computer-readable storage medium; the computer instructions are read and executed by a processor of a computer device to implement the clutch control method as described in any one of claims 1 to 5.

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