A crankcase ventilation system, an engine assembly, and a vehicle

Abstract

This application provides a crankcase ventilation system, an engine assembly, and a vehicle. The crankcase ventilation system includes a first intake manifold, a second intake manifold, a bypass manifold, a crankcase, a cylinder head, and an intake manifold. The first intake manifold is equipped with a throttle valve, and the outlet of the intake manifold is connected to the cylinder head. The intake end of the second intake manifold is connected to the intake end of the first intake manifold, and the outlet end of the second intake manifold is connected to the crankcase. The second intake manifold is equipped with a switching valve for opening or closing the passage between the intake end of the second intake manifold and the crankcase. One end of the bypass manifold is connected between the intake end of the second intake manifold and the switching valve, and the other end of the bypass manifold is connected between the outlet of the throttle valve and the inlet of the intake manifold. In this application's crankcase ventilation system, the in-cylinder air-fuel mixture is less and the cylinder pressure is lower before the next engine start-up.

Description

Technical Field

[0001] This application relates to the field of engine technology, and in particular to a crankcase ventilation system, engine assembly, and vehicle. Background Technology

[0002] For hybrid vehicle engines, compared to traditional gasoline engines, start-stop operation no longer exists solely during idling. Under normal driving conditions, the engine will also start and stop in response to the vehicle's needs. If the engine operated under high load for an extended period during the previous driving cycle and then stopped due to vehicle requirements, the shutdown strategy will cause negative pressure to form in the intake manifold, drawing residual fuel-air mixture from the cylinders into the crankcase. After the engine stops, the throttle valve returns to the limp-out position, and the intake manifold pressure equals atmospheric pressure, thus shoveling the residual fuel-air mixture back into the cylinders. When the engine starts again, there is a fuel-air mixture in the cylinders, resulting in higher cylinder pressure at start-up. Utility Model Content

[0003] This application provides a crankcase ventilation system, an engine assembly, and a vehicle, aiming to improve the problem of excessive cylinder pressure during engine start-up in existing engines.

[0004] To address the aforementioned problems, this application provides a crankcase ventilation system, including a first intake pipe, a second intake pipe, a crankcase, a cylinder head, and an intake manifold; wherein,

[0005] The first intake pipe is equipped with a throttle valve, which is connected between the intake end of the first intake pipe and the inlet of the intake manifold, and the outlet of the intake manifold is connected to the cylinder head.

[0006] The intake end of the second intake pipe is connected to the intake end of the first intake pipe, and the outlet end of the second intake pipe is connected to the crankcase. The second intake pipe is provided with a switch valve for opening or closing the passage between the intake end of the second intake pipe and the crankcase.

[0007] One end of the curved pipe is connected between the intake end of the second intake pipe and the switch valve, and the other end of the curved pipe is connected between the outlet of the throttle valve and the inlet of the intake manifold.

[0008] The crankcase ventilation system of this application embodiment includes a switching valve on the second intake pipe for opening or closing the passage between the intake end of the second intake pipe and the crankcase. Thus, during shutdown, closing the switching valve closes the passage between the intake end of the second intake pipe and the crankcase, meaning the intake end of the second intake pipe is not connected to the crankcase. At this time, the throttle opening is small (0-5%), generating negative pressure in the intake manifold, and the air-fuel mixture from the crankcase is drawn into the intake manifold. After the engine stops, the throttle returns to the limp-out position, and the throttle opening returns to the preset mechanical opening (8%-10%). The intake manifold is connected to the outside atmosphere through the first intake pipe, and the air pressure in the intake manifold returns to atmospheric pressure. However, because the switching valve remains closed, the passage between the intake end of the second intake pipe and the crankcase remains closed. The air-fuel mixture in the crankcase cannot enter the crankcase, and therefore, the air-fuel mixture in the intake manifold cannot enter the cylinders either. The air-fuel mixture in the intake manifold remains inside the intake manifold. Thus, after the engine stops, there is less air-fuel mixture in the cylinders, resulting in lower cylinder pressure. This avoids compression ignition during engine start-up, reduces vibration noise during start-up, and improves the engine's NVH performance.

[0009] During the period from the start of the shutdown command to the completion of the next start-up, the switching valve remains closed. At other times, the switching valve must remain open, connecting the intake end of the second intake manifold to the crankcase to meet the forced ventilation requirements of the crankcase. Start-up is complete upon receiving a signal indicating successful ignition of all cylinders.

[0010] Optionally, the switching valve is an electromagnetic switching valve;

[0011] It also includes a vehicle controller, which is signal-connected to the solenoid valve. The vehicle controller can control the solenoid valve to open or close, so as to open or close the passage between the intake end of the second intake pipe and the crankcase.

[0012] When the vehicle controller controls the switch valve to open, it opens the passage between the intake end of the second intake pipe and the crankcase, connecting the intake end of the second intake pipe to the crankcase. When the vehicle controller controls the switch valve to close, it closes the passage between the intake end of the second intake pipe and the crankcase, disconnecting the intake end of the second intake pipe from the crankcase.

[0013] The switching valve is an electromagnetic switching valve, which is easy to control. The vehicle controller and the electromagnetic switching valve are connected via a signal line; alternatively, the vehicle controller and the switching solenoid valve are wirelessly connected, that is, wireless transceiver modules are respectively installed on the vehicle controller and the switching solenoid valve for communication between the two.

[0014] The Vehicle Controller Unit (VCU), also known as the powertrain controller, is the core control component of the entire vehicle. It collects signals from the accelerator pedal, brake pedal, and other components, makes corresponding judgments, and then controls the actions of the lower-level component controllers to drive the vehicle normally. As the vehicle's command and management center, the powertrain controller's main functions include: drive torque control, optimized braking energy control, overall vehicle energy management, CAN network maintenance and management, fault diagnosis and handling, and vehicle status monitoring. It plays a crucial role in controlling vehicle operation.

[0015] Optionally, the first intake manifold is further provided with a turbocharger, and the throttle valve is connected between the outlet of the turbocharger and the inlet of the intake manifold.

[0016] A turbocharger can pressurize the intake air, increase the intake volume, allow more oxygen to participate in combustion, resulting in more complete combustion and improving the engine's power and output torque.

[0017] Optionally, it also includes a pressure sensor disposed in the intake manifold, the pressure sensor being used to detect the air pressure in the intake manifold.

[0018] The pressure sensor indirectly calculates the engine's intake air volume by detecting pressure changes within the intake manifold. Intake air volume is a core factor for the electronic control unit (ECU) in determining fuel injection quantity and ignition timing. The pressure sensor can also detect abnormal pressure within the intake manifold (such as leaks or blockages), triggering an ECU alarm or entering a protection mode.

[0019] Optionally, it also includes an electronic control unit, which is signal-connected to the pressure sensor.

[0020] The electronic control unit (ECU) and the pressure sensor are connected via a signal line; alternatively, the ECU and the pressure sensor are wirelessly connected, meaning that wireless transceiver modules are installed on both the ECU and the pressure sensor for communication between them.

[0021] The Electronic Control Unit (ECU), also known as the "vehicle computer" or "on-board computer," is similar to a regular computer. It consists of a microprocessor (MCU), memory (ROM, RAM), input / output interfaces (I / O), analog-to-digital converters (A / D), and large-scale integrated circuits for shaping and driving. The MCU is the core of the ECU, possessing computational and control functions. When the engine is running, it collects signals from various sensors, performs calculations, and converts the results into control signals to control the operation of the controlled object. It also controls the memory, input / output interfaces, and other external circuits. The program stored in the ROM is based on data obtained through precise calculations and extensive experiments. This inherent program continuously compares and calculates with the signals collected from various sensors while the engine is running. The results of these comparisons and calculations are used to control multiple parameters of the engine, such as ignition, air-fuel ratio, idle speed, and exhaust gas recirculation.

[0022] Optionally, it also includes an air filter, the inlet of which is used for air intake, and the outlet of which is connected to the air intake end of the first air intake pipe and the air intake end of the second air intake pipe.

[0023] Air filters remove impurities from the engine's intake air, preventing these impurities from damaging the engine.

[0024] Optionally, it further includes a first one-way valve, which is connected between the outlet of the air filter and the inlet end of the first air intake pipe and the inlet end of the second air intake pipe. The first one-way valve only allows airflow from the air filter to the inlet end of the first air intake pipe and the inlet end of the second air intake pipe.

[0025] The first one-way valve can prevent gas backflow in the first and second intake pipes, which would affect intake efficiency.

[0026] Optionally, it also includes a second one-way valve, which is disposed in the curved pipe and allows airflow only from the second intake pipe to the curved pipe.

[0027] The second one-way valve ensures that airflow can only enter the crankcase or engine intake pipe from the crankcase, and cannot reverse, in order to meet the forced ventilation requirements.

[0028] Optionally, it also includes an oil-gas separator connected between the switching valve and the crankcase.

[0029] The oil-gas separator can separate the gas and liquid (fuel) in the oil-gas mixture coming out of the crankcase. The separated liquid flows into the oil pan, while the gas enters the intake manifold through the second intake pipe and the bypass pipe.

[0030] Optionally, it also includes a three-way pipe, the second intake pipe includes a first pipe and a second pipe, the switch valve is arranged in the second pipe, the first port of the three-way pipe is connected to one end of the first pipe, the second port of the three-way pipe is connected to one end of the second pipe, and the third port of the three-way pipe is connected to one end of the curved pipe.

[0031] The system is equipped with a T-junction pipe, which can connect the second intake pipe to the bend pipe, and the pipe structure is simple.

[0032] On the other hand, this application provides an engine assembly including the crankcase ventilation system described in the above embodiments.

[0033] The engine assembly of this application embodiment has all the advantages of the crankcase ventilation system of the above embodiments.

[0034] In another aspect, embodiments of this application provide a vehicle including the crankcase ventilation system of the above embodiments or the engine assembly of the above embodiments.

[0035] The vehicle of this application embodiment has all the advantages of the crankcase ventilation system of the above embodiments. Attached Figure Description

[0036] Figure 1 This is a schematic diagram of a crankcase ventilation system provided in one embodiment of the present invention;

[0037] Figure 2 This is a schematic diagram of a crankcase ventilation system provided in another embodiment of the present invention.

[0038] The reference numerals in the accompanying drawings are as follows:

[0039] 1. First intake manifold; 11. Turbocharger; 12. Throttle valve; 2. Second intake manifold; 21. Switch valve; 22. First manifold; 23. Second manifold; 3. Turning pipe; 4. Crankcase; 5. Cylinder head; 6. Intake manifold; 7. Vehicle controller; 8. Pressure sensor; 9. Electronic control unit; 10. Air filter; 20. First check valve; 30. Second check valve; 40. Oil separator; 50. T-junction. Detailed Implementation

[0040] To make the technical problems solved, technical solutions, and beneficial effects of this utility model clearer, the present utility model will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain this utility model and are not intended to limit this utility model.

[0041] See Figure 1 This utility model provides a crankcase ventilation system, including a first intake pipe 1, a second intake pipe 2, a tortuous pipe 3, a crankcase 4, a cylinder head 5, and an intake manifold 6. The first intake pipe 1 is provided with a throttle valve 12, which is connected between the intake end of the first intake pipe 1 and the inlet of the intake manifold 6. The outlet of the intake manifold 6 is connected to the cylinder head 2. The intake end of the second intake pipe 2 is connected to the intake end of the first intake pipe 1, and the outlet end of the second intake pipe 2 is connected to the crankcase 4. The second intake pipe 2 is provided with a switch valve 21 for opening or closing the passage between the intake end of the second intake pipe 2 and the crankcase 4. One end of the tortuous pipe 3 is connected between the intake end of the second intake pipe 2 and the switch valve 21, and the other end of the tortuous pipe 3 is connected between the outlet of the throttle valve 12 and the inlet of the intake manifold 6.

[0042] In the crankcase ventilation system of this embodiment, a switching valve 21 is provided on the second intake pipe 2 to open or close the passage between the intake end of the second intake pipe 2 and the crankcase 4. Thus, during shutdown, closing the switching valve 21 closes the passage between the intake end of the second intake pipe 2 and the crankcase 4, meaning the intake end of the second intake pipe 2 is not connected to the crankcase 4. At this time, the throttle valve 12 has a small opening (0-5%), generating negative pressure in the intake manifold 6, and the air-fuel mixture from the crankcase 3 is drawn into the intake manifold 6. After the engine stops, the throttle valve 12 returns to the limp-out position, and its opening returns to the preset mechanical opening (8%-10%). The intake manifold 6 is connected to the outside atmosphere through the first intake pipe 1, and the air pressure in the intake manifold 6 returns to atmospheric pressure. However, since the switching valve 21 remains closed, the passage between the intake end of the second intake pipe 2 and the crankcase 4 remains closed. The air-fuel mixture in the crankcase 4 cannot enter the crankcase pipe 3, preventing the air-fuel mixture in the intake manifold 6 from entering the cylinder. The air-fuel mixture in the intake manifold 6 remains inside the intake manifold 6. Thus, before the next start-up, there is less air-fuel mixture in the cylinder, resulting in lower cylinder pressure. This avoids compression ignition during start-up, reduces vibration noise during start-up, and improves the engine's NVH performance.

[0043] During the period from the start of the shutdown command to the completion of the next start-up, the switching valve 21 remains closed. At other times, the switching valve 21 must remain open, connecting the intake end of the second intake pipe 2 to the crankcase 4 to meet the forced ventilation requirements of the crankcase 4. The start-up is complete upon receiving a signal indicating successful ignition of all cylinders of the engine.

[0044] In one embodiment, a turbocharger 11 is also provided on the first intake pipe 1, and a throttle valve 12 is connected between the outlet of the turbocharger 11 and the inlet of the intake manifold 6.

[0045] During and after shutdown, the turbocharger 11 stops working. The turbocharger 11 can allow airflow but does not pressurize it. The turbocharger 11 can pressurize the intake air, increase the intake volume, allow more oxygen to participate in combustion, resulting in more complete combustion and improving the engine's power and output torque.

[0046] In one embodiment, see Figure 1 The switching valve 21 is an electromagnetic switching valve; it also includes a vehicle controller 7, which is connected to the electromagnetic switching valve. The vehicle controller 7 can control the electromagnetic switching valve to open or close, so as to open or close the passage between the intake end of the second intake pipe 2 and the crankcase 4.

[0047] When the vehicle controller 7 controls the switch valve 21 to open, it opens the passage between the intake end of the second intake pipe 2 and the crankcase 4, thus connecting the intake end of the second intake pipe 2 to the crankcase 4. When the vehicle controller 7 controls the switch valve 21 to close, it closes the passage between the intake end of the second intake pipe 2 and the crankcase 4, thus disconnecting the intake end of the second intake pipe 2 from the crankcase 4.

[0048] The switching valve 21 is an electromagnetic switching valve, which is easy to control. The vehicle controller 7 is connected to the electromagnetic switching valve via a signal line; or, the vehicle controller and the switching solenoid valve are wirelessly connected, that is, the vehicle controller 7 and the switching solenoid valve are respectively equipped with wireless transceiver modules for communication between the two.

[0049] The Vehicle Controller Unit (VCU), also known as the powertrain controller, is the core control component of the entire vehicle. It collects signals from the accelerator pedal, brake pedal, and other components, makes corresponding judgments, and then controls the actions of the lower-level component controllers to drive the vehicle normally. As the vehicle's command and management center, the powertrain controller's main functions include: drive torque control, optimized braking energy control, overall vehicle energy management, CAN network maintenance and management, fault diagnosis and handling, and vehicle status monitoring. It plays a crucial role in controlling vehicle operation.

[0050] In one embodiment, see Figure 1It also includes a pressure sensor 8 disposed in the intake manifold 6, which is used to detect the air pressure in the intake manifold 6. It also includes an electronic control unit 9, which is signal-connected to the pressure sensor 8.

[0051] Pressure sensor 8 indirectly calculates the engine's intake air volume by detecting pressure changes within the intake manifold 6. The intake air volume is a core basis for the electronic control unit (ECU) to determine the fuel injection quantity and ignition advance angle. Pressure sensor 8 can also monitor for pressure anomalies within the intake manifold 6 (such as leaks or blockages), triggering an alarm in the ECU 9 or entering a protection mode.

[0052] The electronic control unit 9 is connected to the pressure sensor 8 via a signal line; or, the electronic control unit 9 is wirelessly connected to the pressure sensor 8, that is, the electronic control unit 9 and the pressure sensor 8 are respectively equipped with wireless transceiver modules for communication between the two.

[0053] The Electronic Control Unit (ECU), also known as the "vehicle computer" or "on-board computer," is similar to a regular computer. It consists of a microprocessor (MCU), memory (ROM, RAM), input / output interfaces (I / O), analog-to-digital converters (A / D), and large-scale integrated circuits for shaping and driving. The MCU is the core of the ECU, possessing computational and control functions. During engine operation, it collects signals from various sensors, performs calculations, and converts the results into control signals to control the operation of the controlled object. It also controls the memory, input / output interfaces, and other external circuits. The program stored in the ROM is based on data obtained through precise calculations and extensive experiments. This inherent program continuously compares and calculates with the signals collected from various sensors during engine operation. The results of these comparisons and calculations are used to control multiple parameters of the engine, such as ignition, air-fuel ratio, idle speed, and exhaust gas recirculation.

[0054] In one embodiment, see Figure 1 It also includes an air filter 10, the inlet of which is used for air intake, and the outlet of which is connected to the air intake end of the first air intake pipe 1 and the air intake end of the second air intake pipe 2.

[0055] Air filter 10 removes impurities from the engine intake air, preventing them from damaging the engine.

[0056] In one embodiment, see Figure 1 It also includes a first one-way valve 20, which is connected between the outlet of the air filter 10 and the inlet end of the first intake pipe 1 and the inlet end of the second intake pipe 2. The first one-way valve 20 only allows airflow from the air filter 10 to the inlet end of the first intake pipe 1 and the inlet end of the second intake pipe 2.

[0057] The first one-way valve 20 can prevent gas backflow in the first intake pipe 1 and the second intake pipe 2 from affecting the intake efficiency.

[0058] In one embodiment, see Figure 1 It also includes a second one-way valve 30, which is located in the curved pipe 3. The second one-way valve 30 only allows airflow from the second air inlet pipe 2 to the curved pipe 3.

[0059] The second one-way valve 30 ensures that airflow can only enter the crankcase 4 or the engine intake end into the crank pipe 3, and cannot reverse, in order to meet the forced ventilation requirements.

[0060] In one embodiment, see Figure 1 It also includes an oil-gas separator 40, which is connected between the switching valve 21 and the crankcase 4.

[0061] The oil-gas separator 40 can separate the gas and liquid (fuel) in the oil-gas mixture coming out of the crankcase 4. The separated liquid flows into the oil pan, while the gas enters the intake manifold 6 through the second intake pipe 2 (when the switch valve 21 is open) and the bypass pipe 3.

[0062] In one embodiment, see Figure 1 It also includes a three-way pipe 50, the second intake pipe 2 includes a first pipe 22 and a second pipe 23, the switch valve 21 is arranged in the second pipe 23, the first interface of the three-way pipe 50 is connected to one end of the first pipe 22, the second interface of the three-way pipe 50 is connected to one end of the second pipe 23, and the third interface of the three-way pipe 50 is connected to one end of the curved pipe 3.

[0063] A three-way pipe 50 is provided, which can connect the second intake pipe 2 and the curved pipe 3. The pipe structure is simple.

[0064] Additionally, see Figure 2 Another embodiment of this application provides a crankcase ventilation system, which is compatible with... Figure 1 The difference in the illustrated embodiment is that the supercharger 11 has been omitted, resulting in a simpler structure.

[0065] On the other hand, this application provides an engine assembly including the crankcase ventilation system described in the above embodiments.

[0066] The engine assembly of this application embodiment has all the advantages of the crankcase ventilation system of the above embodiments.

[0067] In another aspect, embodiments of this application provide a vehicle including the crankcase ventilation system of the above embodiments or the engine assembly of the above embodiments.

[0068] The vehicle of this application embodiment has all the advantages of the crankcase ventilation system of the above embodiments.

[0069] The above are merely preferred embodiments of the present utility model and are not intended to limit the present utility model. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present utility model should be included within the protection scope of the present utility model.

Claims

1. A crankcase ventilation system characterized in that, This includes the first intake manifold, the second intake manifold, the crankcase, the cylinder head, and the intake manifold; among which, The first intake pipe is equipped with a throttle valve, which is connected between the intake end of the first intake pipe and the inlet of the intake manifold, and the outlet of the intake manifold is connected to the cylinder head. The intake end of the second intake pipe is connected to the intake end of the first intake pipe, and the outlet end of the second intake pipe is connected to the crankcase. The second intake pipe is provided with a switch valve for opening or closing the passage between the intake end of the second intake pipe and the crankcase. One end of the curved pipe is connected between the intake end of the second intake pipe and the switch valve, and the other end of the curved pipe is connected between the outlet of the throttle valve and the inlet of the intake manifold.

2. A crankcase ventilation system according to claim 1, characterised in that The switching valve is an electromagnetic switching valve; It also includes a vehicle controller, which is signal-connected to the solenoid valve. The vehicle controller can control the solenoid valve to open or close, so as to open or close the passage between the intake end of the second intake pipe and the crankcase.

3. The crankcase ventilation system according to claim 1, wherein The first intake manifold is also equipped with a turbocharger, and the throttle valve is connected between the outlet of the turbocharger and the inlet of the intake manifold.

4. The crankcase ventilation system of claim 1, wherein, It also includes a pressure sensor disposed in the intake manifold, the pressure sensor being used to detect the air pressure in the intake manifold; It also includes an electronic control unit, which is connected to the pressure sensor signal.

5. The crankcase ventilation system of claim 1 wherein, It also includes an air filter, the inlet of which is used for air intake, and the outlet of which is connected to the air intake end of the first air intake pipe and the air intake end of the second air intake pipe.

6. A crankcase ventilation system according to claim 5, characterised in that It also includes a first one-way valve, which is connected between the outlet of the air filter and the inlet end of the first air intake pipe and the inlet end of the second air intake pipe. The first one-way valve only allows airflow from the air filter to the inlet end of the first air intake pipe and the inlet end of the second air intake pipe.

7. The crankcase ventilation system of claim 1 wherein, It also includes a second one-way valve, which is disposed in the curved pipe and allows airflow only from the second intake pipe to the curved pipe.

8. The crankcase ventilation system of claim 1 wherein, It also includes an oil-gas separator, which is connected between the switching valve and the crankcase.

9. The crankcase ventilation system of claim 1 wherein, It also includes a three-way pipe, the second intake pipe includes a first pipe and a second pipe, the switch valve is arranged in the second pipe, the first interface of the three-way pipe is connected to one end of the first pipe, the second interface of the three-way pipe is connected to one end of the second pipe, and the third interface of the three-way pipe is connected to one end of the curved pipe.

10. An engine assembly characterized by, Includes the crankcase ventilation system as described in any one of claims 1-9.

11. A vehicle characterized by comprising: Includes the crankcase ventilation system as described in any one of claims 1-9 or the engine assembly as described in claim 10.

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