Crankcase ventilation system, engine and vehicle
By controlling the airflow through the venturi tube and the first valve in the crankcase ventilation system, the problem of gas not being able to be discharged under high engine load conditions is solved, achieving efficient exhaust gas discharge and stable ventilation effect.
Patent Information
- Application Number
- CN202520537510.6
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-03-25
- Publication Date
- 2026-01-09
- Estimated Expiration
- 2035-03-25
AI Technical Summary
When the engine is under high load, the gas in the crankcase cannot effectively enter the intake manifold, resulting in positive pressure in the crankcase and affecting the exhaust gas discharge.
A crankcase ventilation system is adopted, including an air intake pipe and a first exhaust pipe. The airflow is controlled by a venturi tube and a first valve. By collecting throttle opening information, a negative pressure is formed at the throat to achieve rapid gas discharge.
It improves the reliability and stability of the crankcase ventilation system, enhances the efficiency of exhaust gas discharge, and reduces fuel consumption and harmful gas emissions.
Smart Images
Figure CN223781503U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of vehicle technology, and in particular to a crankcase ventilation system, an engine, and a vehicle. Background Technology
[0002] When the engine is running, the high-pressure combustible mixture and burned gas in the combustion chamber will leak into the crankcase to some extent through the gap between the piston assembly and the cylinder, causing blow-by. To prevent excessive crankcase pressure, extend the service life of engine oil, reduce wear and corrosion of parts, and prevent engine oil leaks, crankcase ventilation must be implemented.
[0003] The crankcase ventilation system is used to guide exhaust gases from the crankcase into the intake system while simultaneously introducing fresh air into the crankcase for gas exchange, allowing for re-combustion within the cylinders. This prevents unburned exhaust gases from deteriorating the engine oil in the crankcase; it's a structure that improves combustion and emissions. When the engine is under high load, the pressure inside the crankcase increases. Simultaneously, because the throttle is fully open, the pressure in the intake manifold approaches atmospheric pressure, resulting in a smaller relative pressure difference between the crankcase and the intake manifold. This prevents gases from entering the intake manifold, creating positive pressure within the crankcase, which is detrimental to exhaust gas discharge. Utility Model Content
[0004] This application provides a crankcase ventilation system, an engine, and a vehicle to solve the problem that when the engine is under high load conditions, the gas in the crankcase cannot enter the intake manifold, resulting in positive pressure in the crankcase, which is not conducive to exhaust gas discharge.
[0005] The first aspect of this application provides a crankcase ventilation system, the crankcase ventilation system including an air intake pipe and a first exhaust pipe;
[0006] The air intake pipeline includes a turbocharger, a throttle valve, and an intake manifold connected in sequence via pipes;
[0007] The first exhaust pipe includes an oil-gas separator and a venturi tube. The converging section of the venturi tube is connected to the intake end of the throttle valve, the diffuser section of the venturi tube is connected to the intake end of the turbocharger, the throat of the venturi tube is connected to the oil-gas separator, and a first valve is also provided between the converging section of the venturi tube and the intake end of the throttle valve.
[0008] When the engine is under high load, the throttle opening is large. The first valve collects throttle opening information. If the throttle opening exceeds a set threshold, the first valve opens, connecting to the constriction section to connect the air intake and exhaust pipes. Gas can then flow from the constriction section to the diffuser section; that is, airflow passes through the venturi tube from the constriction section to the diffuser section. In the constriction section, the airflow velocity gradually increases and the pressure decreases. When the fluid enters the throat, the velocity reaches its maximum and the pressure drops to its minimum. In the diffuser section, the velocity gradually decreases and the pressure gradually recovers.
[0009] Under the negative pressure inside the throat, the gas in the oil-gas separator is drawn into the venturi tube through the throat, and then discharged through the diffuser section connected to the throttle valve. It flows through the turbocharger to the throttle valve, and then flows out from the throttle valve into the intake manifold, thereby allowing the gas to be discharged into the engine cylinder. This facilitates the rapid discharge of the gas in the oil-gas separator along the first path. Subsequently, the gas can smoothly pass through the turbocharger, throttle valve, and intake manifold in sequence and be discharged into the engine cylinder.
[0010] In this embodiment, the crankcase ventilation system includes a first valve and a venturi tube. The first valve collects throttle opening information to determine if the engine is under high load, and then controls the first valve to open. High-speed airflow flows through the venturi tube, creating negative pressure in the throat. Gas from the oil-gas separator is drawn into the venturi tube under this negative pressure and then discharged from the diffuser. The gas discharged from the oil-gas separator can then travel along a first path to the intake end of the turbocharger. Subsequently, the gas passes through the turbocharger, throttle, and intake manifold before entering the engine cylinders. Therefore, by collecting throttle opening information, the first valve determines the engine's operating condition and controls the flow of gas through the venturi tube, improving the reliability and stability of the crankcase ventilation system's rapid exhaust, thus facilitating crankcase exhaust and increasing the efficiency of the crankcase ventilation system's exhaust.
[0011] In this scheme, the first valve is a PCV valve equipped with an electronic control module.
[0012] In this solution, the crankcase ventilation system further includes a second exhaust pipe, which includes a second valve and the oil-gas separator. The second valve is connected between the oil-gas separator and the intake manifold.
[0013] In this scheme, the second valve is a PCV valve.
[0014] In this solution, the crankcase ventilation system further includes a first breather pipe, and the intake manifold and the second valve are connected through the first breather pipe.
[0015] In this solution, the crankcase ventilation system further includes a third exhaust pipe, which includes an air filter, a second breather pipe, and the cylinder of the engine. The second breather pipe is used to connect the air filter to the cylinder of the engine.
[0016] In this design, the oil-gas separator is connected to the throat via the second breathing tube.
[0017] In this design, the air intake pipe also includes an intercooler, which is connected to the intake end of the throttle valve and the exhaust end of the turbocharger.
[0018] A second aspect of this application provides an engine, the engine including a crankcase, cylinders and a crankcase ventilation system, wherein the crankcase ventilation system is the crankcase ventilation system described above.
[0019] The intake manifold in the crankcase ventilation system is connected to the cylinder;
[0020] The oil-gas separator is connected to the crankcase.
[0021] A third aspect of this application provides a vehicle comprising the engine described above.
[0022] It should be understood that the above general description and the following detailed description are merely exemplary and do not limit this application. Attached Figure Description
[0023] Figure 1 This is a schematic diagram of the crankcase ventilation system provided in this application in a specific embodiment, wherein the engine is under high load conditions;
[0024] Figure 2 This is a schematic diagram of the crankcase ventilation system provided in this application in a specific embodiment;
[0025] Figure 3 This is a schematic diagram illustrating the working principle of the crankcase ventilation system provided in this application in one specific embodiment.
[0026] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this application and, together with the description, serve to explain the principles of this application.
[0027] Explanation of reference numerals in the attached figures:
[0028] 1-Crankcase ventilation system;
[0029] 11-Oil-gas separator;
[0030] 12-Intake manifold;
[0031] 13-Throttle body;
[0032] 14-Venturi tube;
[0033] 141-Throat;
[0034] 142-Diffusion section;
[0035] 143 - Contraction segment;
[0036] 151 - First valve;
[0037] 152 - Second valve;
[0038] 161 - First breathing tube;
[0039] 162 - Second breathing tube;
[0040] 17-Air filter;
[0041] 18-Turbocharger;
[0042] 19-Intercooler;
[0043] 2-Engine;
[0044] 21-Crankcase;
[0045] 22-Cylinder. Detailed Implementation
[0046] To better understand the technical solution of this application, the embodiments of this application will be described in detail below with reference to the accompanying drawings.
[0047] In one specific embodiment, the present application will be further described in detail below with reference to specific embodiments and accompanying drawings.
[0048] It should be understood that the described embodiments are merely some, not all, of the embodiments in this application. All other embodiments obtained by those skilled in the art based on the embodiments in this application without inventive effort are within the scope of protection of this application.
[0049] The terminology used in the embodiments of this application is for the purpose of describing particular embodiments only and is not intended to be limiting of this application. The singular forms “a,” “the,” and “the” used in the embodiments of this application and the appended claims are also intended to include the plural forms unless the context clearly indicates otherwise.
[0050] It should be understood that the term "and / or" used in this article is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, and B existing alone. Additionally, the character " / " in this article generally indicates that the preceding and following related objects have an "or" relationship.
[0051] It should be noted that the directional terms such as "upper," "lower," "left," and "right" described in the embodiments of this application are used to describe the angles shown in the accompanying drawings and should not be construed as limiting the embodiments of this application. Furthermore, in the context, it should be understood that when it is mentioned that an element is connected "upper" or "lower" to another element, it can be directly connected to the other element "upper" or "lower," or indirectly connected to the other element "upper" or "lower" through an intermediate element.
[0052] The crankcase ventilation system is an important component for ensuring internal engine pressure balance, reducing emissions, and protecting the environment. Its main function is to expel gases generated during engine operation from the crankcase while preventing these gases from being directly released into the atmosphere and causing pollution.
[0053] As the engine piston moves downwards, it forces some unburned air-fuel mixture and combustion products into the crankcase through the gaps in the piston rings. Directly expelling this mixture would cause environmental pollution and waste fuel. The crankcase ventilation system utilizes the vacuum in the engine's intake manifold to draw this mixture into the cylinders via the PCV valve, allowing it to mix with fresh air before re-entering the cylinders for combustion. However, under high engine load conditions, the pressure in the crankcase increases. Simultaneously, with the throttle fully open, the pressure in the intake manifold approaches atmospheric pressure, resulting in a smaller relative pressure difference between the crankcase and the intake manifold. This prevents gases from entering the intake manifold, creating positive pressure in the crankcase and hindering the expulsion of the mixed exhaust gases.
[0054] To address the aforementioned problems, embodiments of this application provide a crankcase ventilation system 1, such as... Figures 1-3 As shown, the crankcase ventilation system 1 includes an air intake pipe and a first exhaust pipe. The air intake pipe includes a turbocharger 18, a throttle valve 13, and an intake manifold 12 connected in sequence via pipes. Air enters the cylinder 22 after passing through the throttle valve 13 and then the intake manifold 12 under the action of the turbocharger 18.
[0055] The first exhaust pipe includes an oil-gas separator 11 and a venturi tube 14. The venturi tube 14 may include a throat 141, a converging section 143, and a diffuser section 142. The converging section 143 of the venturi tube 14 is connected to the intake end of the throttle valve 13, the diffuser section 142 of the venturi tube 14 is connected to the intake end of the turbocharger 18, and the throat 141 of the venturi tube 14 is connected to the oil-gas separator 11. A first valve 151 is also provided between the converging section 143 of the venturi tube 14 and the intake end of the throttle valve 13. The first valve 151 is used to control the connection or disconnection between the converging section 143 of the venturi tube 14 and the intake end of the throttle valve 13 according to the opening degree of the throttle valve 13.
[0056] The throat 141 is located between the contraction section 143 and the diffuser section 142, and its outlet is connected to the inlet of the diffuser section 142. The outlet of the diffuser section 142 is connected to the inlet of the intake manifold 12 via the turbocharger 18. According to Bernoulli's principle, the high-pressure air flowing into the venturi tube 14 is converted into high-speed air, and the gas at the throat 141 of the venturi tube 14 is in a high-speed, low-pressure state.
[0057] Specifically, when engine 2 is under high load, the air pressure near the intake manifold 12 is positive, while the air pressure near the turbocharger 18, which is relatively close to the air intake pipe, is negative. This results in a small pressure difference between the air pressure near the turbocharger 18 and the air pressure near the oil-gas separator 11. When gas is discharged from the oil-gas separator 11, there is a risk that the gas may not be able to flow to the turbocharger 18. This application addresses this by installing a venturi tube 14, which connects the diffuser section 142 of the venturi tube 14 with the turbocharger 18. The intake end of the turbocharger 18 is connected, and the throat 141 of the venturi tube 14 is connected to the oil-gas separator 11. Under the negative pressure in the throat 141 of the venturi tube 14, the gas in the oil-gas separator 11 is drawn into the venturi tube 14 through the throat 141, so that the gas at the diffuser section 142 of the venturi tube 14 is in a high-speed, low-pressure state and flows smoothly to the turbocharger 18. The gas then flows into the intake manifold 12 through the turbocharger 18 so that the engine 2 can exhaust smoothly under high load conditions.
[0058] like Figure 1 and Figure 3As shown, when engine 2 is under high load, the throttle valve 13 is open. The first valve 151 collects the throttle valve 13 opening information. If the throttle valve 13 opening information is greater than a set threshold, the first valve 151 opens, connecting with the constriction section 143 to connect the air intake pipe and the first exhaust pipe. Gas can flow from the constriction section 143 to the diffuser section 142. That is, at this time, there is airflow in the venturi tube 14 from the constriction section 143 to the diffuser section 142. In the constriction section 143, the airflow velocity gradually increases and the pressure decreases; when the fluid enters the throat 141, the velocity reaches its maximum value and the pressure drops to its minimum. In the diffuser section 142, the velocity gradually decreases and the pressure gradually recovers.
[0059] Under the negative pressure within the throat 141, the gas in the oil-gas separator 11 is drawn into the venturi tube 14 through the throat 141, then discharged through the diffuser section 142 connected to the throttle valve 13, flowing through the turbocharger 18 to the throttle valve 13, and then flowing out from the throttle valve 13 into the intake manifold 12, thereby allowing the gas to be discharged into the cylinder 22 of the engine 2. This facilitates the flow of gas from the oil-gas separator 11 along... Figure 1 The gas is quickly discharged through the first path shown, and then it can be smoothly discharged into the cylinder 22 of the engine 2 through the turbocharger 18, throttle body 13, and intake manifold 12 in sequence.
[0060] In this embodiment, the crankcase ventilation system 1 is equipped with a first valve 151 and a venturi tube 14. The first valve 151 can collect the opening information of the throttle valve 13 to determine that the engine 2 is under high load, and then control the first valve 151 to open. High-speed airflow flows in the venturi tube 14, forming a negative pressure in the throat 141. The gas in the oil-gas separator 11 is drawn into the venturi tube 14 under the action of the negative pressure in the throat 141 and then discharged from the diffuser section 142. That is, the gas discharged from the oil-gas separator 11 can flow along the... Figure 1 The gas exits through the first path to the intake end of the turbocharger 18, and then sequentially passes through the turbocharger 18, throttle valve 13, and intake manifold 12 before entering the cylinder 22 of the engine 2. Therefore, the first valve 151 determines the operating condition of the engine 2 by collecting throttle valve 13 opening information, controlling whether gas can flow through the venturi tube 14, improving the reliability and stability of the crankcase ventilation system 1's rapid exhaust, facilitating crankcase 21 exhaust, and improving the efficiency of the crankcase ventilation system 1's exhaust.
[0061] The oil-gas separator 11 is used to filter the gas discharged from the crankcase 21 and to separate the oil from the gas, so as to avoid the risk of oil contaminating other components in the crankcase ventilation system 1 when it is discharged with the gas, reduce the risk of failure, and enable the crankcase ventilation system 1 to operate efficiently.
[0062] In one possible implementation, such as Figure 1As shown, the first valve 151 is a PCV valve equipped with an electronic control module. The first valve 151 can receive electrical signals and adjust its opening degree according to the received electrical signals so that it can open when the throttle valve 13 is open. Gas can then be conducted between the constriction section 143 of the venturi tube 14 and the outlet end of the turbocharger 18, so that the venturi tube 14 has an adsorption effect, allowing the exhaust gas to be discharged smoothly.
[0063] The first valve 151 may include a valve body, a valve core, and a spring, etc. The flow rate of the first valve 151 under different pressures can be adjusted through the matching design of the valve core and the spring. In one possible implementation, such as... Figure 2 As shown, the crankcase ventilation system 1 also includes a second exhaust pipe, which includes a second valve 152 and an oil-gas separator 11. The second valve 152 is connected between the oil-gas separator 11 and the intake manifold 12. The second valve 152 is used to collect the opening degree of the throttle valve 13. When the second valve 152 is open, the second exhaust pipe and the intake manifold 12 are connected, and the gas discharged from the oil-gas separator 11 can flow along... Figure 2 The second path shown leads to the intake manifold 12, and then the gas enters the cylinder 22 of the engine 2 for combustion via the intake manifold 12.
[0064] Specifically, when the engine 2 is under low load, the throttle valve 13 is open at a small degree. The first valve 151 collects the throttle valve 13 opening information and closes the first valve 151, that is, the venturi tube 14 is closed, and the gas cannot be discharged along the first path. At the same time, the second valve 152 opens, and the gas can be discharged into the cylinder 22 along the second path.
[0065] In one possible implementation, such as Figure 1 and Figure 2 As shown, the first valve 151 can adjust its opening degree according to the opening degree of the throttle valve 13.
[0066] In this embodiment, when the pressure in the first path is high, the first valve 151 can adjust its own opening according to the opening of the throttle valve 13, adjust the flow rate of the gas in the venturi tube 14, and adjust the flow rate of the gas in the oil-gas separator 11 into the intake manifold 12, so as to avoid the risk of the gas flow rate in the venturi tube 14 being too fast and affecting the oil-gas separation efficiency, which is conducive to reducing fuel consumption.
[0067] In one possible implementation, such as Figure 1 and Figure 2 As shown, the second valve 152 can be a positive crankcase ventilation valve (PCV valve). The second valve 152 can adjust its own opening according to the opening of the throttle valve 13 to control the flow rate and adjust the pressure inside the crankcase 21.
[0068] In one possible implementation, such as Figure 2 As shown, the crankcase ventilation system 1 also includes a first breather pipe 161, and the intake manifold 12 and the second valve 152 are connected through the first breather pipe 161.
[0069] In this embodiment, under low load conditions, the gas in the crankcase 21 first passes through the oil-gas separator 11, and then is discharged into the intake manifold 12 through the first breather pipe 161.
[0070] In one possible implementation, such as Figure 2 As shown, the crankcase ventilation system 1 also includes a third exhaust pipe, which includes an air filter 17 and a second breather pipe 162. The second breather pipe 162 is used to connect the air filter 17 to the cylinder 22 of the engine 2.
[0071] Under low-load conditions, fresh air flows along... Figure 2 The third path shown enters the cylinder 22 of the engine block via the air filter 17 and the second breather pipe 162 to replenish air, thereby promoting the re-combustion of incomplete combustion products in the cylinder and helping to reduce the emission of harmful gases.
[0072] In one possible implementation, such as Figure 1 As shown, the oil-gas separator 11 and the throat 141 are connected through the second breather tube 162. In this embodiment, under high load conditions, the oil-gas separator 11 and the throat 141 are connected through the second breather tube 162, and the gas flows into the venturi tube 14 through the second breather tube 162 and is discharged into the intake manifold 12, improving the reliability of exhaust.
[0073] It should be noted that the power source for exhaust gas discharge relies on the pressure difference between the two ends of the exhaust path. Under low load conditions, the pressure difference between the intake manifold 12 and the crankcase 21 is relatively large, and the pressure inside the crankcase 21 is significantly greater than that at the end closer to the air filter 17. That is, at this time, the pressure difference between the two ends of the first breather pipe 161 is significantly greater than that between the two ends of the second breather pipe 162. Under the action of the pressure difference, the exhaust gas is discharged through the first breather pipe 161 and not through the second breather pipe 162.
[0074] In one possible implementation, such as Figure 1 As shown, the air piping also includes an intercooler 19, which is connected to the intake end of the throttle valve 13 and the exhaust end of the turbocharger 18.
[0075] In this example, when gas flows through the venturi tube 14 through the turbocharger 18, the turbocharger's turbine forces more fresh air into the intake manifold 12, improving combustion efficiency and helping to reduce the emission of harmful gases.
[0076] Meanwhile, the intercooler 19 is used to reduce the temperature of the gas compressed by the turbocharger 18, increase the gas density and oxygen content, improve combustion efficiency, reduce the emission of unburned fuel and harmful gases, thereby reducing the risk of exceeding emission standards.
[0077] This application also provides an engine 2, such as Figure 1 and Figure 2 As shown, the engine 2 includes a crankcase 21, a cylinder 22, and a crankcase ventilation system 1. The crankcase ventilation system 1 is the crankcase ventilation system 1 in any of the above embodiments. The intake manifold 12 in the crankcase ventilation system 1 is connected to the cylinder 22, and the oil-gas separator 11 is connected to the crankcase 21.
[0078] When the crankcase ventilation system 1 is used in engine 2, the crankcase ventilation system 1 is equipped with a first valve 151 and a venturi tube 14. The first valve 151 determines that engine 2 is under high load based on the throttle valve 13 opening information, and controls the opening of the first valve 151. This allows for high-speed airflow within the venturi tube 14. Gas from the oil-gas separator 11 is drawn into the venturi tube 14 under the action of this high-speed airflow and is quickly discharged into the intake manifold 12. Therefore, the first valve 151 determines the operating condition of engine 2 by collecting throttle valve 13 opening information, controlling whether gas can flow within the venturi tube 14. This improves the reliability and stability of the rapid exhaust of the crankcase ventilation system 1, facilitates the discharge of exhaust gas from the crankcase 21, and improves the exhaust efficiency and performance of engine 2.
[0079] This application also provides a vehicle, which includes the engine 2 in any of the above embodiments.
[0080] When engine 2 is used in a vehicle, the first valve 151 determines the operating condition of engine 2 by collecting throttle valve 13 opening information, controls whether gas can flow in venturi tube 14, improves the reliability and stability of engine 2 exhaust, facilitates the discharge of vehicle exhaust gas, and improves vehicle exhaust efficiency and performance. The above description is merely a specific implementation of the embodiments of this application, but the protection scope of the embodiments of this application is not limited thereto. Any changes or substitutions within the technical scope disclosed in the embodiments of this application should be covered within the protection scope of the embodiments of this application. Therefore, the protection scope of the embodiments of this application should be determined by the protection scope of the claims.
Claims
1. A crankcase ventilation system, characterized in that, The crankcase ventilation system includes an air intake pipe and a first exhaust pipe; The air intake pipeline includes a turbocharger, a throttle valve, and an intake manifold connected in sequence via pipes; The first exhaust pipe includes an oil-gas separator and a venturi tube. The converging section of the venturi tube is connected to the intake end of the throttle valve, the diffuser section of the venturi tube is connected to the intake end of the turbocharger, the throat of the venturi tube is connected to the oil-gas separator, and a first valve is also provided between the converging section of the venturi tube and the intake end of the throttle valve.
2. The crankcase ventilation system according to claim 1, characterized in that, The first valve is a PCV valve equipped with an electronic control module.
3. The crankcase ventilation system according to claim 1, characterized in that, The crankcase ventilation system also includes a second exhaust pipe, which includes a second valve and the oil-gas separator. The second valve is connected between the oil-gas separator and the intake manifold.
4. The crankcase ventilation system according to claim 3, characterized in that, The second valve is a PCV valve.
5. The crankcase ventilation system according to claim 3, characterized in that, The crankcase ventilation system also includes a first breather pipe, and the intake manifold and the second valve are connected through the first breather pipe.
6. The crankcase ventilation system according to any one of claims 1-5, characterized in that, The crankcase ventilation system also includes a third exhaust pipe, which includes an air filter and a second breather pipe. The second breather pipe is used to connect the air filter to the cylinder of the engine.
7. The crankcase ventilation system according to claim 6, characterized in that, The oil-gas separator is connected to the throat via the second breathing tube.
8. The crankcase ventilation system according to any one of claims 1-5, characterized in that, The air intake pipe also includes an intercooler, which is connected to the intake end of the throttle valve and the exhaust end of the turbocharger.
9. An engine, characterized in that, The engine includes a crankcase, cylinders, and a crankcase ventilation system, wherein the crankcase ventilation system is the crankcase ventilation system according to any one of claims 1-8; The intake manifold in the crankcase ventilation system is connected to the cylinder; The oil-gas separator is connected to the crankcase.
10. A vehicle, characterized in that, The vehicle includes the engine as described in claim 9.