Engine and transmission cooperative thermal management system and method

Abstract

The application discloses an engine and gearbox cooperative thermal management system and a thermal management method, which comprises a gearbox, an engine, a water pump, a five-way pipe, a rotatable ball valve and a radiator, wherein the gearbox is internally provided with a gearbox oil cooler, the radiator is provided with a radiator fan, the water pump is connected with the engine, the engine is connected with the rotatable ball valve, the rotatable ball valve is connected with the five-way pipe and the radiator, and the five-way pipe is connected with the gearbox oil cooler and the water pump. Through the design of the five-way pipe cooperating with the rotatable ball valve device, the engine hot water can be used for rapidly heating the gearbox at a proper time during cold start, and the gearbox can be cooled by cold water when the gearbox is overheated, so that the oil saving effect is achieved.

Description

Technical Field

[0001] This invention relates to the field of engine cooling, and more specifically to an engine and transmission coordinated thermal management system and thermal management method. Background Technology

[0002] Currently, the cooling system solutions used in vehicles on the market are usually mechanical water pumps + thermostats. The thermostat is used to regulate the two branches: the radiator large circulation and the bypass small circulation. In fact, the small circulation is hot water that does not pass through the radiator for cooling. The coolant in the large circulation branch before passing through the radiator is also hot water. The water temperature in this part can reach 90-105℃ under normal use, while the water temperature of the coolant in the large circulation branch that has passed through the radiator will be about 10℃ lower, at a level of 75-90℃.

[0003] Transmission oil temperature generally has a limited range of operating values. For example, it needs to be kept below 90°C for a long time. In order to cool the oil, the water temperature flowing into the oil cooler must be lower than the oil temperature, that is, the water temperature needs to be below 90°C. In the entire system circulation, only the part cooled by the radiator can meet this requirement.

[0004] Therefore, the transmission oil cooler typically draws water from behind the radiator for cooling. In this type of cooling system, when the engine coolant temperature is high and the radiator is constantly open, water flows inside the transmission oil cooler, providing cooling. However, during cold starts, the transmission cannot be heated before the coolant temperature reaches a high level, resulting in higher oil viscosity and friction. Furthermore, under slippery conditions, the transmission oil temperature rises rapidly. This necessitates rapidly opening the full circulation loop to suppress the rapid temperature increase. However, switching the engine cooling loop too quickly from a small loop to a full circulation loop can cause a rapid drop in engine coolant temperature. This rapid temperature change can cause thermal shock to the engine block and cylinder head, damaging the engine. Summary of the Invention

[0005] In view of this, the present invention provides an engine and transmission coordinated thermal management system and thermal management method. Through the design of a five-way pipe and a rotatable ball valve device, it can not only use the engine's hot water to quickly warm up the transmission at the appropriate time during cold start, but also cool down the transmission with cold water when the transmission is overheated, thereby achieving a fuel-saving effect.

[0006] The present invention provides an engine and transmission coordinated thermal management system, including a transmission, an engine, a water pump, a five-way pipe, a rotatable ball valve, and a radiator. The transmission is equipped with a transmission oil cooler. The water pump is connected to the engine, the engine is connected to the rotatable ball valve, the rotatable ball valve is connected to the five-way pipe and the radiator, and the five-way pipe is connected to the transmission oil cooler and the water pump.

[0007] Furthermore, the rotatable ball valve has a ball valve inlet on one side and a first ball valve outlet and a second ball valve outlet on the other side. The engine is connected to the ball valve inlet, the first ball valve outlet is connected to the five-way pipe, and the second ball valve outlet is connected to the radiator. The opening degree of the first ball valve outlet and the second ball valve outlet is adjustable.

[0008] Furthermore, the five-way pipe includes a first-way valve inlet, a second-way valve inlet, a third-way valve inlet, a first-way valve outlet, and a second-way valve outlet. The rotatable ball valve is connected to the first-way valve inlet, the radiator is connected to the second-way valve inlet, the transmission oil cooler is connected to the third-way valve inlet and the first-way valve outlet, and the water pump is connected to the second-way valve outlet.

[0009] Furthermore, an oil temperature sensor is connected to the transmission oil cooler, and a water temperature sensor is provided between the engine and the rotatable ball valve.

[0010] The present invention also provides a thermal management method for the engine and transmission coordinated thermal management system as described above, comprising the following steps: initiating a cold start, acquiring the actual coolant temperature of the engine, and acquiring the actual oil temperature of the transmission; during the cold start process, determining whether the coolant temperature of the engine is higher than the transmission response threshold; if the coolant temperature of the engine is higher than the transmission response threshold, then warming up the transmission; determining whether the transmission warm-up is complete; if the transmission warm-up is complete, determining whether the oil temperature of the transmission is higher than the transmission oil temperature threshold; if the oil temperature of the transmission is lower than the transmission oil temperature threshold, then executing a conventional strategy; if the oil temperature of the transmission is higher than the transmission oil temperature threshold, then the cooling system enters the transmission over-temperature protection mode.

[0011] Furthermore, it also includes: when the vehicle is powered on, the system performs a self-test to check whether the rotatable ball valve will have a jamming fault. If a jamming fault occurs, the engine speed and torque are limited. If the system is normal, it determines whether the water temperature sensor is faulty. If the water temperature sensor is not faulty, a cold start is started. The water temperature sensor is used to obtain the actual water temperature of the engine.

[0012] Furthermore, the heat engine of the gearbox includes: opening the first ball valve outlet of the rotatable ball valve and closing the second ball valve outlet.

[0013] Furthermore, determining whether the warm-up of the transmission has ended includes: when the transmission oil temperature exceeds the transmission warm-up threshold, the warm-up of the transmission has ended, and the system exits the warm-up phase of the transmission.

[0014] Furthermore, the transmission oil temperature thresholds include a first transmission oil temperature threshold, a second transmission oil temperature threshold, and a third transmission oil temperature threshold; the cooling system entering the transmission over-temperature protection mode includes: if the transmission oil temperature exceeds the first transmission oil temperature threshold, opening the first ball valve outlet of the rotatable ball valve and closing the second ball valve outlet to cool the transmission using coolant; if the transmission oil temperature exceeds the second transmission oil temperature threshold, opening the first ball valve outlet and the second ball valve outlet of the rotatable ball valve to cool the transmission using coolant and the radiator; if the transmission oil cooler temperature exceeds the third transmission oil temperature threshold, closing the first ball valve outlet of the rotatable ball valve and opening the second ball valve outlet to cool the transmission using the radiator.

[0015] Furthermore, the first transmission fluid temperature threshold is lower than the second transmission fluid temperature threshold, and the second transmission fluid temperature threshold is lower than the third transmission fluid temperature threshold.

[0016] Compared with existing technologies, the present invention has the following beneficial technical effects:

[0017] This invention provides an engine and transmission coordinated thermal management system and method. It uses an adjustable rotatable ball valve to actively control the water temperature, replacing the conventional thermostat, which can achieve fuel saving and emission reduction of the engine. In addition, through the five-way pipe and the rotatable ball valve, it can switch between the transmission oil cooling branch and the engine small and large circulation, which can ensure that the transmission receives the best cooling effect in the overheating mode. Furthermore, during the cold start stage, it can accelerate the warm-up speed of the transmission without affecting the engine heating, thereby reducing the friction loss of the engine and transmission at the same time and reducing the fuel consumption of the powertrain system. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the engine and transmission coordinated thermal management system of the present invention.

[0019] Figure 2 This is a flowchart of the thermal management method of the present invention.

[0020] Figure 3 This is a schematic diagram of the structure of stage one in the thermal management method of the present invention.

[0021] Figure 4This is a schematic diagram of the second stage of the thermal management method of the present invention.

[0022] Figure 5 This is a schematic diagram of stage three in the thermal management method of the present invention.

[0023] Figure 6 This is a schematic diagram of stage four in the thermal management method of the present invention.

[0024] Wherein: 10-Gearbox; 11-Gearbox oil cooler; 20-Engine; 30-Water pump; 40-Five-way pipe; 41-First-way valve inlet; 42-Second-way valve inlet; 43-Third-way valve inlet; 44-First-way valve outlet; 45-Second-way valve outlet; 50-Rotable ball valve; 51-Ball valve inlet; 52-First-way valve outlet; 53-Second-way valve outlet; 60-Radiator; 61-Radiator fan; 70-Oil temperature sensor; 80-Water temperature sensor. Detailed Implementation

[0025] The specific embodiments of the present invention will be described in further detail below with reference to the accompanying drawings and examples. The following examples are for illustrative purposes only and are not intended to limit the scope of the invention.

[0026] Please refer to Figure 1 The present invention provides an engine and transmission coordinated thermal management system, including a transmission 10, an engine 20, a water pump 30, a five-way pipe 40, a rotatable ball valve 50, and a radiator 60. The transmission 10 is equipped with a transmission oil cooler 11, and the radiator 60 is equipped with a radiator fan 61. The water pump 30 is connected to the engine 20, the engine 20 is connected to the rotatable ball valve 50, the rotatable ball valve 50 is connected to the five-way pipe 40 and the radiator 60, and the five-way pipe 40 is connected to the transmission oil cooler 11 and the water pump 30.

[0027] Specifically, the rotatable ball valve 50 has a ball valve inlet 51 on one side and a first ball valve outlet 52 and a second ball valve outlet 53 on the other side. The ball valve inlet 51 can communicate with the first ball valve outlet 52 and the second ball valve outlet 53 by rotating the rotatable ball valve 50. The engine 20 and the ball valve inlet 51 are connected by a pipe, the first ball valve outlet 52 and the five-way pipe 40 are connected by a pipe, and the second ball valve outlet 53 and the radiator 60 are connected by a pipe. The opening degree of the first ball valve outlet 52 and the second ball valve outlet 53 can be adjusted according to the water temperature. The five-way pipe 40 includes a first valve inlet 41, a second valve inlet 42, a third valve inlet 43, a first valve outlet 44, and a second valve outlet 45, and these valve inlets are interconnected. Rotatable ball valve 50 is connected to the inlet 41 of the first-way valve via a pipe; radiator 60 is connected to the inlet 42 of the second-way valve via a pipe; transmission oil cooler 11 is connected to the inlet 43 of the third-way valve and the outlet 44 of the first-way valve via a pipe; and water pump 30 is connected to the outlet 45 of the second-way valve via a pipe.

[0028] Furthermore, an oil temperature sensor 70 is connected to the transmission oil cooler 11, which can monitor the oil temperature of the transmission 10 in real time; a water temperature sensor 80 is connected between the engine 20 and the rotatable ball valve 50, which can monitor the water temperature of the engine 20 in real time.

[0029] Please refer to Figures 2-6 This invention also provides a thermal management method for an engine and transmission coordinated thermal management system. Through the design of a rotatable ball valve 50 and a five-way pipe 40, it is possible to switch between the transmission oil cooling branch and the engine's small circulation (not connected to the radiator 60) and large circulation (connected to the radiator 60). During cold starts, hot water from the engine 20 is used to quickly warm up the transmission 10 at appropriate times. Furthermore, when the transmission 10 overheats, cold water is used to cool it down, thereby achieving fuel savings. This thermal management method specifically includes the following steps:

[0030] S1, the vehicle is powered on and the system performs a self-test.

[0031] After the vehicle is powered on, the engine control system (EMS) begins a self-test. This self-test includes a controller self-test and a check of the rotatable ball valve 50. The most important check is for any jamming issues with the rotatable ball valve 50. If everything is normal, proceed to the next step. If jamming occurs, such as when the valve is stuck in the fully closed position, the entire system will be shut down, losing flow. This poses a risk of overheating to the engine 20. Furthermore, because the internal hot water will not flow to the outside, external sensors such as the water temperature sensor 80 will be unable to accurately detect the internal hot water temperature and will be unable to effectively monitor it. In this case, the system will issue an alarm, the engine 20 will be torque-limited, and the engine controller will send a signal to the rotatable ball valve 50 to adjust its opening to the maximum, ensuring that the radiator 60 is fully open and the system has sufficient cooling.

[0032] S2, after the system self-test is completed, if everything is normal, then determine whether the water temperature sensor 80 is faulty.

[0033] If the system is normal, it is necessary to further determine whether the water temperature sensor 80 is faulty. The main check is whether the water temperature sensor 80 can monitor the water temperature of the engine 20 in real time and accurately. If the water temperature sensor 80 is normal, proceed to the next step. If the water temperature sensor 80 is faulty, the engine controller will alarm and require the rotatable ball valve 50 to be opened to full opening. At the same time, the radiator fan 61 will be turned on to prevent the engine 20 from overheating.

[0034] S3. If the water temperature sensor 80 is normal, the system will start a cold start. At this time, the water temperature sensor 80 reads the actual water temperature of the engine 20 and the oil temperature sensor 70 reads the actual oil temperature of the transmission oil cooler 11.

[0035] If the water temperature sensor 80 is functioning normally, the actual water temperature value of the engine 20 is read. Simultaneously, it checks whether the engine 20 is operating. This is primarily determined by the engine speed; if this value is not zero, it indicates that the engine 20 is running. The system sets different target water temperatures based on the engine speed and load, which can be obtained by looking up a table. Then, the target water temperature and the actual water temperature are compared, and PID control is applied to adjust the opening of the rotatable ball valve 50 and the speed of the radiator fan 61 before outputting the correct values. During this process, the main operating logic of the engine 20 only considers fuel saving and emission reduction.

[0036] To coordinate the thermal management of the engine 20 and transmission 10, the engine control system (EMS) controls the rotatable ball valve 50 and radiator fan 61 within its main logic framework, while simultaneously monitoring the transmission oil temperature of the transmission 10, which is connected to the vehicle network. The oil temperature sensor 70 reads the actual oil temperature of the transmission oil cooler 11. This actual oil temperature is generally stored within the transmission controller (TCU), but it is transmitted to the vehicle's CAN network. The EMS can capture this signal through interaction with the vehicle's CAN network and use it for internal judgment.

[0037] S4. During the cold start process, determine whether the coolant temperature of the engine 20 is higher than the transmission response threshold. If the coolant temperature of the engine 20 is higher than the transmission response threshold, then warm up the transmission 10.

[0038] During the cold start process, requirements can be divided into the following levels:

[0039] a. First, the wall temperature of engine 20 rises rapidly, entering the optimal state of combustion. This process can usually be completed within tens of seconds, at which time the water temperature is 30~40℃.

[0040] b. The following is the process of engine oil temperature rising. The viscosity of engine oil is high at low temperature, which will lead to higher friction loss of engine oil. In addition, engine oil is prone to dilution under low temperature conditions. Therefore, it is necessary to heat the engine oil quickly so that the oil temperature can reach a suitable temperature quickly. At this time, the water temperature is about 80°C.

[0041] In the preceding two processes, to lock all the heat inside engine 20 and generate a temperature rise, the transmission cooling circulation branch was kept closed. The oil temperature inside transmission 10 remained subcooled and its viscosity was high. As a moving mechanical component, transmission 10 also suffers from high frictional losses. If the transmission cooling circulation branch were directly connected to the engine's small circulation loop, causing the engine 20 oil and transmission 10 oil to rise simultaneously, a trade-off would occur: the transmission 10 oil would rise faster, resulting in a slower rise in engine 20 oil temperature. Given that engine 20 is the power output source, its frictional losses account for a higher proportion of the entire powertrain system and are therefore more important than those of the transmission. Furthermore, the main cause of oil dilution in engine 20 is gasoline wetting the walls under low-temperature conditions, a problem not present in transmission 10. Therefore, the oil temperature rise of engine 20 takes precedence over that of transmission 10. In the overall strategy, it is necessary to ensure that the engine 20 oil temperature reaches a certain level before initiating the transmission 10 oil temperature rise.

[0042] Based on the above requirements, the strategy is defined as follows:

[0043] During a cold start, if the coolant temperature is below the transmission response threshold, the rotatable ball valve 50 does not respond to any external stimuli, focusing only on the rapid warm-up of the engine 20 itself. The rotatable ball valve 50 operates primarily in three ways:

[0044] a. According to Figure 3 The system operates as shown in Phase 1: when the first ball valve outlet 52 and the second ball valve outlet 53 of the rotatable ball valve 50 are closed, all branches are shut off, and there is zero flow in the system.

[0045] b. Rotary ball valve 50 slightly opens the outlet 53 of the second ball valve, while closing all other branches;

[0046] c. The first ball valve outlet 52 and the second ball valve outlet 53 of the rotatable ball valve 50 intermittently switch between the on and off modes.

[0047] When the water temperature exceeds the gearbox response threshold, the position can be adjusted by rotating the ball valve 50. Figure 4Phase Two: The first ball valve outlet 52 of the rotatable ball valve 50 is opened, and the second ball valve outlet 53 is closed. The position is adjusted so that the transmission oil cooler branch is open, but the radiator branch is closed. Hot water inside the engine 20 begins to flow through the transmission cooler 11 of the transmission 10, heating the transmission oil. During this process, the opening degree of the first ball valve outlet 52 of the rotatable ball valve 50 is related to the water temperature; the higher the water temperature, the larger the opening. The opening degree of the first ball valve outlet 52 of the rotatable ball valve 50 can be obtained by looking up the water temperature in a table and output for control.

[0048] S5 determines whether the warm-up of transmission 10 has ended.

[0049] When the water temperature exceeds the engine warm-up threshold, it indicates that the engine 20 has finished warming up and the system exits the engine 20 warm-up stage. At this time, the rotatable ball valve 50 is adjusted according to the target water temperature and the actual water temperature. Based on the relevant control strategy of the engine 20, different target water temperatures are obtained by looking up the table according to different operating conditions, and the opening degree of the rotatable ball valve 50 and the operating conditions of the radiator fan 61 are set.

[0050] During this temperature closed-loop control process, the rotatable ball valve 50 may be opened to a larger or smaller position. However, considering that the transmission oil temperature of the transmission 10 may not have reached the ideal level, it is necessary to determine whether the transmission oil temperature of the transmission 10 exceeds the transmission warm-up threshold. If the transmission oil temperature of the transmission 10 is still lower than this value, the lower limit of the opening of the rotatable ball valve 50 is constrained. That is, regardless of the closed-loop effect, it is necessary to ensure that at least the transmission oil cooler branch is open, but the radiator 60 branch is closed. If the transmission oil temperature of the transmission 10 has exceeded the transmission warm-up threshold, the warm-up of the transmission 10 has ended. At this time, the system can adjust the rotatable ball valve 50 normally according to the internal logic of the engine 20.

[0051] S6, after the transmission 10 has finished warming up, it is determined whether the transmission oil temperature of the transmission 10 is higher than the transmission oil temperature threshold. If the transmission oil temperature of the transmission 10 is lower than the transmission oil temperature threshold, the normal strategy is executed. The normal strategy refers to closed-loop control of the rotatable ball valve based on the engine coolant temperature. If the transmission oil temperature of the transmission 10 is higher than the transmission oil temperature threshold, the cooling system enters the transmission 10 over-temperature protection mode. The over-temperature protection mode refers to controlling the opening of the rotatable ball valve and the radiator fan according to the transmission oil temperature.

[0052] After the engine 20 and transmission 10 have completed the warm-up process, the cooling capacity adjustment of the cooling system should return to the main focus of adjusting the engine 20 water temperature. The water temperature should be adjusted in a closed loop according to the different operating conditions of the engine 20. However, on this basis, the overheating of the engine 20 and transmission 10 should be considered, that is, the overheating should be dealt with to ensure the reliability of the system.

[0053] The overheat control of engine 20 is a standard strategy of the rotatable ball valve 50 and is relatively simple. For example, when the water temperature exceeds the overheat threshold, the rotatable ball valve 50 is forcibly opened to the fully open position of radiator 60, and the small circulation is completely closed, so that the cooling flow of the whole system reaches the maximum value and all flows through radiator 60 for heat exchange. In addition, radiator fan 61 is turned on to the highest speed.

[0054] However, the overheat control of the transmission 10 cannot be set in this way. Generally, under normal and high temperature conditions, when the engine 20's coolant and oil temperatures are high, the transmission 10's oil temperature is also often high. Conversely, in cold regions with low temperatures, when the engine 20's coolant and oil temperatures are low, the transmission 10's oil temperature is also low. When both temperatures rise and fall together and the demand is unified, the control strategy of the rotatable ball valve 50 is consistent and will not encounter problems. However, in certain special circumstances, such as long-slope traffic jams in low-temperature environments ranging from -20℃ to 10℃, the transmission 10 is in a prolonged slipping state, causing the transmission 10's oil temperature to rise rapidly. However, at this time, the engine 20's operating conditions are still insufficient to support the rise in coolant temperature, which remains at a decreasing level. Under such conditions, when the transmission 10's oil temperature triggers the ball valve to its maximum opening, the coolant temperature drops sharply due to the increased heat exchange capacity of the engine 20. After the transmission 10's oil temperature drops, the rotatable ball valve 50 returns to its minimum opening, and the coolant temperature rises again. This back-and-forth will cause thermal shocks, which are detrimental to the operation of both the engine 20 and the transmission 10.

[0055] Therefore, to meet the cooling requirements of the transmission 10, the flow rate should be gradually increased as the oil temperature rises, rather than directly using the strategy of "demanding maximum cooling performance directly when the oil temperature exceeds the transmission oil temperature threshold".

[0056] Based on the connection of the transmission oil cooler 11 to the engine 20's large and small circulation loops using a five-way pipe 40, the cooling performance supply is divided into three levels through the adjustment of the rotatable ball valve 50. The transmission oil temperature thresholds are set as the first transmission oil temperature threshold, the second transmission oil temperature threshold, and the third transmission oil temperature threshold.

[0057] a. Rotatable ball valve 50 opens the outlet 52 of the first ball valve in the small circulation loop, allowing coolant to enter the inlet 41 of the first valve in the five-way pipe 40. A portion of the cooling flow is allocated to the transmission oil cooler 11, ensuring cooling flow within the transmission oil cooler 11. However, the radiator branch remains closed. Figure 4 The state of stage two is shown.

[0058] b. Rotatable ball valve 50 opens the first ball valve outlet 52 and the second ball valve outlet 53, ensuring flow in the transmission oil cooler 11 and the radiator 60, i.e. Figure 5 The state of stage three is shown.

[0059] c. Rotary ball valve 50 closes the outlet 52 of the first ball valve, and the outlet 53 of the second ball valve opens to its maximum degree, allowing all cooling flow to pass through the radiator 60, and turning on the radiator fan 61. Figure 6 The state of stage four is shown.

[0060] That is, under any circumstances, when the transmission oil temperature exceeds the first transmission oil temperature threshold, the ball valve 50 can be rotated to at least open the first ball valve outlet 52, ensuring cooling flow in the transmission oil cooler 11, but the radiator branch is closed. Figure 4 The state shown is stage two. In this way, the heat inside the gearbox 10 can be carried away. During this process, the opening degree of the first ball valve outlet 52 of the rotatable ball valve 50 is related to the oil temperature. The higher the oil temperature, the larger the opening degree.

[0061] In any situation, when the transmission fluid temperature exceeds the second transmission fluid temperature threshold, ball valve 50 can be rotated to open the first ball valve outlet 52 and the second ball valve outlet 53, ensuring flow in the transmission oil cooler 11 and the radiator 60. Figure 5 The state shown is stage three. In this way, the heat inside the gearbox 10 can be carried away, and most of the flow flows through the radiator 60 to dissipate heat to the outside. During this process, the opening degree of the first ball valve outlet 52 and the second ball valve outlet 53 of the rotatable ball valve 50 is related to the oil temperature. The higher the oil temperature, the larger the opening degree.

[0062] If the transmission fluid temperature continues to rise and exceeds the third transmission fluid temperature threshold, then the first ball valve outlet 52 of the rotatable ball valve 50 is closed, and the second ball valve outlet 53 is fully opened, allowing all cooling flow to pass through the radiator 60. Figure 6 The state shown is stage four, and the radiator fan 61 is turned on. During this process, the opening degree of the second ball valve outlet 53 of the rotatable ball valve 50 is related to the oil temperature; the higher the oil temperature, the larger the opening degree.

[0063] As described above, the present invention provides a thermal management system and method for engine and transmission coordination. It utilizes an adjustable, rotatable ball valve to actively control the water temperature, replacing the conventional thermostat, thereby achieving fuel saving and emission reduction in the engine. Furthermore, through a five-way pipe in conjunction with the rotatable ball valve, it enables switching between the transmission oil cooling circuit and the engine's small and large circulation loops, ensuring optimal cooling performance for the transmission in overheating mode. In addition, during the cold start phase, it accelerates the warm-up speed of the transmission while ensuring that engine heating is not affected, thereby simultaneously reducing friction losses in both the engine and transmission and lowering fuel consumption in the powertrain system.

[0064] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. An engine and transmission coordinated thermal management system, characterized in that, The system includes a gearbox (10), an engine (20), a water pump (30), a bottom bracket (40), a rotatable ball valve (50), a radiator (60), and a controller. The gearbox (10) contains a transmission oil cooler (11). The water pump (30) is connected to the engine (20), the engine (20) is connected to the rotatable ball valve (50), the rotatable ball valve (50) is connected to the bottom bracket (40) and the radiator (60), the radiator (60) is connected to the bottom bracket (40), and the bottom bracket (40) is connected to the transmission oil cooler (11) and the water pump (30). The system also includes a water temperature sensor (80) for detecting engine coolant temperature and an oil temperature sensor (70) for detecting transmission oil temperature. The controller is signal-connected to the water temperature sensor (80), the oil temperature sensor (70), and the rotatable ball valve (50) and is configured as follows: During a cold start, when the engine coolant temperature is higher than the transmission response threshold, the rotatable ball valve (50) is controlled to open the flow path to the five-way pipe (40) and close the flow path to the radiator (60) so as to use the engine coolant as a heat engine for the transmission. When the transmission oil temperature is higher than the transmission oil temperature threshold, the rotatable ball valve (50) is controlled in stages to open the outlet opening of the flow path to the radiator (60) according to the oil temperature exceeding multiple incremental thresholds, so as to introduce radiator coolant to cool the transmission.

2. The engine and transmission coordinated thermal management system as described in claim 1, characterized in that, The rotatable ball valve (50) has a ball valve inlet (51) on one side and a first ball valve outlet (52) and a second ball valve outlet (53) on the other side. The engine (20) is connected to the ball valve inlet (51), the first ball valve outlet (52) is connected to the five-way pipe (40), and the second ball valve outlet (53) is connected to the radiator (60). The opening degree of the first ball valve outlet (52) and the second ball valve outlet (53) is adjustable.

3. The engine and transmission coordinated thermal management system as described in claim 2, characterized in that, The five-way pipe (40) includes a first-way valve inlet (41), a second-way valve inlet (42), a third-way valve inlet (43), a first-way valve outlet (44), and a second-way valve outlet (45). The rotatable ball valve (50) is connected to the first-way valve inlet (41). The radiator (60) is connected to the second-way valve inlet (42). The transmission oil cooler (11) is connected to the third-way valve inlet (43) and the first-way valve outlet (44). The water pump (30) is connected to the second-way valve outlet (45).

4. A thermal management method for an engine and transmission coordinated thermal management system as described in any one of claims 1-3, characterized in that, Includes the following steps: Start cold start, obtain the actual water temperature of the current engine (20), and obtain the actual oil temperature of the current transmission (10); During the cold start process, it is determined whether the water temperature of the engine (20) is higher than the transmission response threshold. If the water temperature of the engine (20) is higher than the transmission response threshold, the transmission (10) is warmed up. Determine whether the warm-up of the gearbox (10) has ended; If the warm-up of the transmission (10) is over, it is determined whether the oil temperature of the transmission (10) is higher than the transmission oil temperature threshold. If the oil temperature of the transmission (10) is lower than the transmission oil temperature threshold, the rotatable ball valve (50) is closed-loop controlled according to the engine (20) water temperature. If the oil temperature of the transmission (10) is higher than the transmission oil temperature threshold, the cooling system enters the over-temperature protection mode of the transmission (10).

5. The thermal management method as described in claim 4, characterized in that, Also includes: When the vehicle is powered on, the system performs a self-test to check whether the rotatable ball valve (50) will have a jamming fault. If a jamming fault occurs, the engine (20) will be limited in speed and torque. If the system is normal, determine whether the water temperature sensor (80) is faulty; If the water temperature sensor (80) is not faulty, a cold start is initiated; wherein the water temperature sensor (80) is used to obtain the actual water temperature of the engine (20) at present.

6. The thermal management method as described in claim 4, characterized in that, The heat engine of the gearbox (10) includes: opening the first ball valve outlet (52) of the rotatable ball valve (50) and closing the second ball valve outlet (53) of the rotatable ball valve (50).

7. The thermal management method as described in claim 4, characterized in that, Determining whether the warm-up of the gearbox (10) is complete includes: When the oil temperature of the transmission (10) exceeds the transmission warm-up threshold, the warm-up of the transmission (10) is over and the system exits the warm-up phase of the transmission (10).

8. The thermal management method as described in claim 4, characterized in that, The transmission fluid temperature thresholds include a first transmission fluid temperature threshold, a second transmission fluid temperature threshold, and a third transmission fluid temperature threshold; The cooling system enters the over-temperature protection mode of the transmission (10) including: If the oil temperature of the transmission (10) exceeds the first transmission oil temperature threshold, the first ball valve outlet (52) of the rotatable ball valve (50) is opened and the second ball valve outlet (53) of the rotatable ball valve (50) is closed, so that the transmission (10) is cooled by coolant. If the oil temperature of the transmission (10) exceeds the second transmission oil temperature threshold, the first ball valve outlet (52) and the second ball valve outlet (53) of the rotatable ball valve (50) are opened to cool the transmission (10) through the coolant and the radiator (60); If the oil temperature of the transmission oil cooler (11) exceeds the third transmission oil temperature threshold, the first ball valve outlet (52) of the rotatable ball valve (50) is closed and the second ball valve outlet (53) is opened, so that the transmission (10) is cooled by the radiator (60).

9. The thermal management method as described in claim 8, characterized in that, The first transmission fluid temperature threshold is less than the second transmission fluid temperature threshold, and the second transmission fluid temperature threshold is less than the third transmission fluid temperature threshold.

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