Hybrid power gearbox hydraulic module and hydraulic system thereof

Abstract

The invention discloses a hybrid power gearbox hydraulic module and a hydraulic system thereof, and relates to the field of gearbox hydraulic control, the hydraulic system is composed of an oil supply subsystem A, a clutch control subsystem B and a lubrication cooling subsystem C. The oil supply subsystem A supplies oil to the whole system through a mechanical pump and an electronic pump. According to the hybrid power gearbox hydraulic module, the hydraulic system of the hybrid power gearbox hydraulic module and the overall oil supply system, the mechanical pump and the electronic pump are adopted for combined oil supply, the working modes of independent working of the electronic pump, independent working of the mechanical pump and combined working of the mechanical pump and the electronic pump can be achieved according to different working conditions, the working efficiency of the system is improved, and the service life of the electronic pump is prolonged; meanwhile, the displacement of the mechanical pump can be reduced, the size of the mechanical pump is reduced, and the arrangement flexibility is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of transmission hydraulic control, and particularly to a hydraulic module and a hydraulic system for a hybrid transmission. Background Art

[0002] The hydraulic system of a hybrid transmission is a core component of a hybrid vehicle. Its design needs to take into account power transmission, energy recovery, and system stability, and it is an important part of the transmission system. For example, in the patent of a hydraulic system for a hybrid transmission with the publication number CN217002439U, the hydraulic system of the hybrid transmission includes: an execution oil circuit, a lubricating oil circuit, a first oil pump, a second oil pump, and at least one execution mechanism. The first oil pump is respectively connected to the execution oil circuit and the execution mechanism. The first oil pump and the execution oil circuit are used to provide driving force for the execution mechanism. The second oil pump, the lubricating oil circuit, and the execution mechanism are connected. The second oil pump and the lubricating oil circuit are used to provide lubrication and / or cooling, so that the execution oil circuit and the lubricating oil circuit can work separately, and the flow rate and pressure of the execution oil circuit and the lubricating oil circuit can be adjusted according to their respective needs to improve the overall efficiency of the transmission and thus improve fuel economy. Another example is the patent of a hydraulic system for a hybrid transmission with the publication number CN212273020U, which includes a high-pressure oil circuit, a low-pressure oil circuit, a first oil circuit, and a second oil circuit. One end of the high-pressure oil circuit is connected to the fuel tank, and the other end of the high-pressure oil circuit is respectively connected to one end of the first oil circuit and one end of the second oil circuit. The other end of the first oil circuit is connected to the clutch cylinder, and the other end of the second oil circuit is connected to the low-pressure oil circuit. One end of the low-pressure oil circuit is connected to the fuel tank, aiming to solve the technical problems that the hydraulic system of the hybrid transmission in the prior art is difficult to meet the pressure requirements of the wet clutch and the flow requirements of the motor heat dissipation under various different working conditions and has large hydraulic losses. Most of the above-mentioned prior arts improve their overall structures. However, the existing transmission hydraulic systems cannot achieve working modes of the electronic pump working alone, the mechanical pump working alone, and the mechanical pump and the electronic pump working together according to different working conditions. The overall system working efficiency is low, and at the same time, the service life of the overall electronic pump is reduced. It is impossible to ensure that the clutch is not damaged due to the pressure fluctuation of the system, and thus there are certain limitations in use. Summary of the Invention

[0003] The object of the present invention is to provide a hydraulic module and a hydraulic system for a hybrid transmission, so as to solve the problems raised in the above background technology, that is, it is impossible to realize the working modes of the electronic pump working alone, the mechanical pump working alone, and the mechanical pump and the electronic pump working jointly according to different working conditions, the overall system working efficiency is low, and at the same time, the service life of the overall electronic pump is reduced, and it is impossible to ensure the avoidance of the occurrence of the accident that the clutch is damaged due to the pressure fluctuation of the system.

[0004] To achieve the above object, the present invention provides the following technical solution: A hydraulic module and a hydraulic system for a hybrid transmission, including that this hydraulic system is composed of three subsystem modules: an oil supply subsystem A, a clutch control subsystem B, and a lubrication and cooling subsystem C, where: The oil supply subsystem A is provided with a mechanical pump and an electronic pump, and the mechanical pump and the electronic pump are arranged in parallel, and the mechanical pump and the electronic pump supply oil to the whole system; The output end of the oil supply subsystem A is provided with a lubrication and cooling subsystem C, and the lubrication and cooling subsystem C is provided with a main spool, an oil cooler, and a throttle hole. The output end of the mechanical pump is connected to the oil cooler through the throttle hole, and the mechanical pump is connected to the main spool through the throttle hole; The output end of the oil supply subsystem A is provided with a clutch control subsystem B; The clutch control subsystem B is provided with a filter screen, a VFS proportional solenoid valve, an accumulator, and a pressure sensor. The output end of the main spool is connected to the VFS proportional solenoid valve, and an accumulator is provided at the output end of the VFS proportional solenoid valve. The clutch control subsystem B performs electrical signal control through the VFS proportional solenoid valve.

[0005] Furthermore, the oil supply subsystem A is also provided with a main fuel tank, a temperature sensor, a suction filter, and a check valve; The temperature sensor is installed at the bottom of the main fuel tank, and the suction filter is provided at the upper end of the main fuel tank; The mechanical pump and the electronic pump suck oil from the fuel tank through the suction filter to supply oil to the whole hydraulic system. A check valve is provided at the oil outlet of the electronic pump to prevent the oil from leaking to the fuel tank through the electronic pump when the mechanical pump works alone.

[0006] Furthermore, the mechanical pump is driven by an output shaft to provide a pressure source and a flow source for the system; When the rotational speed of the output shaft is low, the mechanical pump and the electronic pump supply oil to the system; When the rotational speed of the output shaft is high, according to different working conditions of the transmission, the mechanical pump works alone to continuously supply oil to the system.

[0007] Furthermore, an accumulator is provided in the oil circuit at the rear end of the VFS proportional solenoid valve to absorb the oil pressure fluctuation when the clutch friction plate and the mating plate are in sliding contact; The pressure sensor monitors the real-time pressure of the system to provide closed-loop control for the input pressure control of the clutch.

[0008] Further, the hydraulic oil reaches the clutch VFS proportional solenoid valve after being filtered by a filter screen. The hydraulic oil passes through the VFS proportional solenoid valve and is filtered again by the filter screen to reach the clutch. When the hydraulic oil in the clutch piston chamber drains, it passes through this filter screen and then drains through the clutch VFS proportional solenoid valve.

[0009] Further, the outlet of the mechanical pump and the outlet of the electronic pump after passing through a check valve converge into the same oil circuit.

[0010] Further, the lubrication and cooling subsystem is mainly composed of cooling lubricating oil circuits to LUB, C1, EM1, and EM2; the LUB oil circuit is provided with throttle holes to lubricate each lubrication point such as bearings and gears, and the LUB oil circuit adjusts the oil supply flow rate of the pump by adjusting the rotational speed of the electronic pump.

[0011] Compared with the prior art, the beneficial effects of the present invention are as follows: For the hydraulic module and its hydraulic system of this hybrid transmission, the overall oil supply system adopts a combined oil supply of a mechanical pump and an electronic pump. According to different working conditions, it can realize working modes of the electronic pump working alone, the mechanical pump working alone, and the mechanical pump and the electronic pump working together. This not only improves the working efficiency of the system, but also extends the service life of the electronic pump. At the same time, it can reduce the displacement of the mechanical pump, shrink the size of the mechanical pump, and improve the flexibility of layout; Further, the clutch control subsystem is provided with small filter screens at the oil inlet and outlet of the clutch control valve, which improves the cleanliness of the hydraulic oil when entering and leaving the clutch cavity and avoids the jamming of the spool valve caused by impurities; an accumulator is provided in the oil circuit entering the clutch cavity, which avoids hydraulic shock caused by the fluctuation of the oil circuit during the process of controlling the clutch engagement; and a feedback oil circuit is provided at the spring end of the clutch control spool valve, so that the spring force, the feedback pressure, and the electromagnetic force form a dynamic balance, and the control of the clutch pressure can achieve a smooth curve linear control; The clutch control subsystem is provided with a pressure sensor, which provides a reliable closed-loop control for the TCU to control the rotational speed of the electronic pump. Through pressure control, the system pressure can always be higher than the maximum required pressure of the clutch, ensuring that the clutch is not damaged due to the pressure fluctuation of the system; Further, in the lubrication and cooling subsystem, the lubrication and cooling oil cools the motors EM1 and EM2 in the transmission after passing through the oil cooler, improving the cooling effect. Each lubrication point controls the flow rate by using a throttle hole, reducing the cost. Brief Description of the Drawings

[0012] Figure 1 It is a schematic diagram of the hydraulic system of the present invention.

[0013] In the figure: 1. Mechanical pump; 2. Electronic pump; 3. Filter screen; 4. VFS proportional solenoid valve; 5. Accumulator; 6. Pressure sensor; 7. Main spool valve; 8. Oil cooler; 11. Oil tank; 12. Suction filter; 13. Temperature sensor. Specific embodiments

[0014] The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0015] Embodiment 1: Please refer to Figure 1 , the present invention provides the following technical solutions: A hydraulic module and its hydraulic system for a hybrid transmission. This hydraulic system is composed of three subsystem modules: an oil supply subsystem A, a clutch control subsystem B, and a lubrication and cooling subsystem C, where: A: Oil supply subsystem: The mechanical pump 1 and the electronic pump 2 supply oil to the entire system; this oil supply subsystem mainly consists of an oil tank 11, a temperature sensor 13, a suction filter 12, a mechanical pump 1, an electronic pump 2, and a check valve. The mechanical pump 1 and the electronic pump 2 suck oil from the oil tank 11 through the suction filter 12 to supply oil to the entire hydraulic system. When the rotational speed of the mechanical pump 1 cannot meet the system requirements, by adjusting the rotational speed of the electronic pump 2, the pressure and flow rate of the entire oil supply system can be guaranteed.

[0016] Among them, the main function of the oil tank 11 is to provide an oil source for the entire system; Among them, the main function of the suction filter 12 is to filter impurities in the oil fluid, provide oil fluid with a higher cleanliness for the entire system, prevent impurities from entering the mechanical pump 1 and the electronic pump 2, causing wear of the pumps; prevent impurities from entering the clutch control subsystem, causing spool valve jamming; prevent entry into the lubrication and cooling subsystem, causing wear of components; In the hydraulic system, at different temperatures, the viscosity of the oil fluid is different, which has a greater impact on the entire control system. Therefore, it is necessary to monitor the temperature of the entire system. The main function of the temperature sensor 13 is to monitor the temperature of the entire hydraulic system and provide parameters for the control of the electronic pump 2 and the clutch proportional valve. When controlling the electronic pump 2, according to different temperature ranges and the system flow rate and pressure requirements, the rotational speed of the electronic pump 2 is controlled; The main function of the electronic pump 2 is to provide a pressure source and a flow source for the system. According to the system requirements, it adjusts different speeds to meet the system's needs. It can provide pressure oil for the control of the clutch and also provide flow for the lubrication and cooling subsystem, thereby meeting the requirements of the hydraulic system for flow and pressure under different working conditions of the transmission. When the entire system needs to generate electricity at idle speed or when parking, the electronic pump 2 works alone to meet the cooling requirements of the motor EM1 and the control combination of the clutch. When the pressure and flow provided by the mechanical pump 1 can meet the system requirements, the electronic pump 2 stops working, improving the efficiency of the entire hydraulic system. The intermittent operation of the electronic pump 2 also extends its own service life; Among them, the mechanical pump 1 is driven by the output shaft to provide a pressure source and a flow source for the system. When the output shaft speed is low, the mechanical pump 1 and the electronic pump 2 work simultaneously to supply oil to the system; when the output shaft speed is high, according to different working conditions of the transmission, the mechanical pump 1 works alone to continuously supply oil to the system to meet the needs of lubrication, cooling and clutch control. The main function of the check valve is: when only the mechanical pump 1 works and the electronic pump 2 stops working, it prevents the pressure oil from pushing the electronic pump 2 to reverse and drain oil, so that the entire system works within a reasonable pressure range. The overall oil supply system uses the mechanical pump 1 and the electronic pump 2 to supply oil jointly, and can achieve the working modes of the electronic pump 2 working alone, the mechanical pump 1 working alone, and the mechanical pump 1 and the electronic pump 2 working together according to different working conditions, which not only improves the working efficiency of the system, but also extends the service life of the electronic pump 2. At the same time, the displacement of the mechanical pump 1 can be reduced, the size of the mechanical pump 1 can be reduced, and the layout flexibility is improved.

[0017] B: Clutch control subsystem: It is mainly composed of a filter screen 3, a VFS proportional solenoid valve 4, an accumulator 5, and a pressure sensor 6; the overall clutch control subsystem is mainly controlled by a VFS proportional solenoid valve 4 to meet the pressure requirements of the clutch under various working conditions; Among them, the mechanical pump 1 and the electronic pump 2 suck oil from the fuel tank 11 through the suction filter 12 to supply oil to the clutch actuator subsystem of the transmission. According to different working conditions, there are three oil supply situations: the electronic pump 2 supplies oil alone, the mechanical pump 1 supplies oil alone, and the electronic pump 2 and the mechanical pump 1 supply oil simultaneously, all of which can achieve the oil supply to the clutch actuator subsystem; The pressure sensor 6 monitors the system pressure to ensure that when the clutch is working, the system pressure is higher than the working pressure of the clutch, preventing the clutch pressure from being insufficient due to pressure fluctuations, and further preventing excessive sliding friction between the friction plate and the mating plate due to insufficient clutch pressure, resulting in ablation or damage of the friction plate. At the same time, the signal of the pressure sensor 6 is transmitted to the TCU, and the speed of the electronic pump 2 can be further adjusted according to the system requirements, so that the electronic pump 2 works within a reasonable speed range, realizing the precise closed-loop control of the system; The control of the clutch adopts a proportional electromagnetic pressure regulating valve, also known as the VFS proportional solenoid valve 4. Its feature is that it can precisely control the pressure and flow rate. The hydraulic oil reaches the VFS proportional solenoid valve 4 after being filtered by the filter screen 3. After passing through the VFS proportional solenoid valve 4, the hydraulic oil reaches the clutch after being filtered again by the filter screen 3. The main function of setting this filter screen 3 is that when the clutch is disengaged, the hydraulic oil in the clutch piston chamber will pass through this filter screen 3 and then through the VFS proportional solenoid valve 4 when draining oil, ensuring that when draining oil, the clutch control valve will not be stuck by impurities. A feedback circuit is provided at the rear end of the VFS proportional solenoid valve 4, that is, a feedback oil circuit is provided at the spring end. When controlling the solenoid valve, it can improve the accuracy of controlling the engagement and disengagement of the clutch. At the same time, an accumulator 5 is provided at the rear end of the VFS proportional solenoid valve 4. This accumulator 5 can absorb the oil vibration and hydraulic shock caused by the fluctuation of the main oil circuit, making the two states of clutch engagement and disengagement more stable. At the same time, a small filter screen 3 is provided to improve the cleanliness of the hydraulic oil when entering and leaving the clutch cavity, avoiding the sticking of the spool valve caused by impurities. Through pressure control, the system pressure can always be higher than the maximum required pressure of the clutch, ensuring that the clutch will not be damaged due to the pressure fluctuation of the system.

[0018] C: Lubrication and cooling subsystem: It is provided with a main spool 7 and a spring, an oil cooler 8, and a throttle orifice; it can achieve sufficient lubrication and cooling of the hybrid transmission bearings, gears, clutches, and motors, enabling the components inside the transmission to work within a reasonable temperature range. The mechanical pump 1 and the electronic pump 2 suck oil from the fuel tank 11 through the suction filter 12 to supply oil to the lubrication and cooling subsystem of the transmission. The lubrication and cooling subsystem is mainly composed of the cooling lubricating oil circuits of LUB, C1, EM1, and EM2; The outlet of the mechanical pump 1 and the outlet of the electronic pump 2 after passing through the check valve converge into the same oil circuit. Whether the electronic pump 2 supplies oil alone, the mechanical pump 1 supplies oil alone, or the electronic pump 2 and the mechanical pump 1 supply oil simultaneously, after passing through the outlet of the pump, they all converge into the same oil circuit. After the oil fluid passes through this oil circuit, it is divided into several oil circuits. One oil circuit supplies oil to the rear-end cooling lubricating oil circuit through a throttle orifice; one oil circuit acts on the pilot end of the main spool 7 through a throttle orifice and jointly controls the left and right movement of the main spool 7 with the spring end of the main spool 7 controlled by the VFS proportional solenoid valve 4. According to different working conditions, the main spool 7 works in the left position, the middle position, and the right position respectively; two oil circuits supply oil to the main spool 7; one oil circuit supplies oil to the clutch. The oil fluid passing through the throttle orifice and the main spool 7 converges into a lubricating and cooling oil circuit, and then is divided into four paths. One path cools the motors EM1 and EM2 after passing through the oil cooler 8; one path cools the clutch C1, one path supplies oil to the LUB lubricating oil circuit. The flow rate of the lubricating and cooling oil to the inside of the gearbox is mainly distributed by the throttle orifices arranged in each pipeline of the gearbox. Throttle orifices are provided in the cooling oil circuits of C1, EM1, and EM2 respectively to distribute the cooling flow rate for EM1 and EM2 respectively. The LUB oil circuit is also provided with throttle orifices to lubricate each lubricating point such as bearings and gears. According to different working conditions, the electronic pump 2 intervenes in a timely manner, and adjusts the oil supply flow rate of the pump by adjusting the rotation speed of the electronic pump 2 to meet the requirements of each cooling and lubricating point under different working conditions of the gearbox; Among them, the working position of the main spool 7 is jointly adjusted by the VFS proportional solenoid valve 4 and its corresponding pilot oil circuit according to the working conditions of the hybrid gearbox. When the gearbox stops working or the clutch needs to be quickly engaged to work, the system needs to quickly establish oil pressure. At this time, by controlling the VFS proportional solenoid valve 4, the oil pressure of the pilot oil circuit of the main spool 7 is made consistent with the oil pressure at the spring end of the main spool 7. Under the action of the spring force, the main spool 7 works in the right position; when the clutch does not need to be engaged or the clutch is working, by controlling the balance relationship between the pressure at port A of the VFS proportional solenoid valve 4, the hydraulic pressure at the pilot end of the main spool 7, and the spring force, the main spool 7 works in the middle position. After the oil fluid passes through the main spool 7, it continuously supplies oil to the lubricating and cooling subsystem; when the output shaft speed is relatively high, the flow rate of the mechanical pump 1 is relatively large, and the system pressure is relatively high, the hydraulic pressure acts on the pilot end of the main spool 7, overcoming the spring force of the main spool 7, and pushing the main spool 7 to work in the left position. Part of the oil fluid passes through the main spool 7 and then supplies oil to the lubricating and cooling subsystem, and part of the oil fluid passes through the main spool 7 and drains oil to between the outlet of the suction filter 12 and the oil suction port of the pump, so that the hydraulic system works within a reasonable pressure range. The lubricating and cooling oil in the lubricating and cooling subsystem cools the motors EM1 and EM2 in the gearbox after passing through the oil cooler 8, improving the cooling effect. Each lubricating point controls the flow rate by using a throttle orifice, reducing the cost.

[0019] In the description of the present invention, it should be noted that unless otherwise clearly specified and defined, the terms "connected" and "coupled" should be understood in a broad sense. For example, it may be a fixed connection, a detachable connection, or an integral connection; it may be a mechanical connection or an electrical connection; it may be directly connected or indirectly connected through an intermediate medium. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0020] Although the present invention has been described in detail with reference to the foregoing embodiments, for those skilled in the art, they can still modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements for some of the technical features. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention shall be included in the protection scope of the present invention.

Claims

1. A hydraulic module of a hybrid transmission and its hydraulic system, characterized in that: This hydraulic system is composed of three subsystem modules: the oil supply subsystem A, the clutch control subsystem B, and the lubrication and cooling subsystem C, where: The oil supply subsystem A is provided with a mechanical pump (1) and an electronic pump (2), and the mechanical pump (1) and the electronic pump (2) are arranged in parallel to supply oil to the entire system; The output end of the oil supply subsystem A is provided with a lubrication and cooling subsystem C, and the lubrication and cooling subsystem C is provided with a main spool valve (7), an oil cooler (8), and a throttle orifice. The output end of the mechanical pump (1) is connected to the oil cooler (8) through the throttle orifice, and the mechanical pump (1) is connected to the pilot end of the main spool valve (7) through the throttle orifice; The output end of the oil supply subsystem A is provided with a clutch control subsystem B; The clutch control subsystem B is provided with a filter screen (3), a VFS proportional solenoid valve (4), an accumulator (5), and a pressure sensor (6). The spring end of the main spool valve (7) is connected to the VFS proportional solenoid valve (4), and an accumulator (5) is arranged at the output end of the VFS proportional solenoid valve (4). The clutch control subsystem B performs electrical signal control through the VFS proportional solenoid valve (4).

2. The hydraulic module and hydraulic system of a hybrid transmission according to claim 1, characterized in that: The oil supply subsystem A is also provided with a main oil tank (11), a temperature sensor (13), a suction filter (12), and a check valve; The temperature sensor (13) is installed at the bottom of the main oil tank (11), and the suction filter (12) is arranged at the upper end of the main oil tank (11). After the oil passes through the suction filter, it supplies oil to the suction ports of both the mechanical pump and the electronic pump at the same time. A check valve is arranged at the outlet of the electronic pump. The mechanical pump (1) and the electronic pump (2) suck oil from the oil tank through the suction filter (12) to supply oil to the entire hydraulic system.

3. A hydraulic module and its hydraulic system for a hybrid transmission according to claim 2, characterized in that: The mechanical pump (1) is driven by the output shaft to provide a pressure source and a flow source for the system; When the rotational speed of the output shaft is low, the mechanical pump (1) and the electronic pump (2) supply oil to the system simultaneously; When the rotational speed of the output shaft is high, the mechanical pump (1) works alone to continuously supply oil to the system according to different working conditions of the gearbox.

4. A hydraulic module of a hybrid transmission and its hydraulic system according to claim 3, characterized in that: An accumulator (5) is arranged in the oil circuit at the rear end of the VFS proportional solenoid valve (4) to absorb oil pressure fluctuations when the clutch friction plate and the mating plate are slidingly combined; The pressure sensor (6) monitors the real-time pressure of the system to provide closed-loop control for the input pressure control of the clutch.

5. A hydraulic module and its hydraulic system for a hybrid transmission according to claim 4, characterized in that: The hydraulic oil reaches the clutch VFS proportional solenoid valve (4) after being filtered by the filter screen (3). The hydraulic oil passes through the VFS proportional solenoid valve (4) and is filtered again by the filter screen (3) to reach the clutch. When the hydraulic oil in the clutch piston chamber is drained, it passes through the filter screen (3) and then is drained through the clutch VFS proportional solenoid valve (4).

6. The hydraulic module of a hybrid transmission and its hydraulic system according to claim 5, characterized in that: The outlet of the mechanical pump (1) and the outlet of the electronic pump (2) after passing through the check valve converge into the same oil circuit.

7. A hydraulic module and its hydraulic system for a hybrid transmission according to claim 6, characterized in that: The lubrication and cooling subsystem is mainly composed of cooling lubricating oil circuits to LUB, C1, EM1, and EM2; The LUB oil circuit is respectively provided with throttle orifices to lubricate each lubrication point such as bearings and gears, and the LUB oil circuit adjusts the oil supply flow rate of the pump by adjusting the rotational speed of the electronic pump (2).

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