Crankcase ventilation system and method and vehicle

Abstract

The invention relates to the field of vehicles, in particular to a crankcase ventilation system and method and a vehicle. The crankcase ventilation system comprises a crankcase, an oil-gas separator and a pressure adjusting assembly, the pressure adjusting assembly comprises a vacuum pump, a gas circuit electromagnetic valve and a gas inlet connecting pipe which are connected in sequence, the pressure adjusting assembly is used for adjusting the negative pressure of the crankcase, the crankcase has the large negative pressure, the gas circuit electromagnetic valve is closed under the normal working condition of an engine, and the gas inlet connecting pipe is opened; the work only depends on the original structure of the crankcase; under the post-treatment heating working condition of engine cold start and other working conditions of large throttle opening, in order to avoid harm caused by large negative pressure of an air inlet cavity, the pressure adjusting assembly works, at the moment, the air path electromagnetic valve is controlled to be communicated with an air path of the crankcase and the air inlet connecting pipe, and the vacuum pump is controlled to work so that the pressure in the crankcase can be controlled; the pressure in the crankcase is still smaller than the pressure in the cylinder, engine oil is prevented from permeating into the cylinder to cause engine oil burning, and the sealing performance is guaranteed.

Description

Technical Field

[0001] The present invention relates to the field of vehicles, and in particular to a crankcase ventilation system, method and vehicle. Background Art

[0002] When the engine is working, the high-temperature and high-pressure gas in the combustion chamber will enter the crankcase along with the piston ring. In order to prevent the crankcase seal from being damaged and reduce the impact on the performance of the engine oil, the gas that has entered the crankcase needs to be discharged in time. With increasingly stringent emission requirements, crankcase ventilation also needs to introduce emission limit control. The most common scenario here is to pass the crankcase exhaust gas through the oil-gas separator, and then introduce the remaining exhaust gas into the inlet of the supercharger through the pipeline, and then re-enter the cylinder with fresh air for combustion to avoid polluting the environment.

[0003] In order to increase the exhaust temperature, achieve post-heating treatment and improve the conversion efficiency, it is usually achieved by increasing fuel injection and reducing the intake volume. However, there is a problem of low negative pressure in the intake chamber of the engine when reducing the intake volume. In order to increase the exhaust temperature, the pressure in the engine intake chamber may be lower than 65kPa. In order to achieve the engine post-treatment heating condition, the negative pressure needs to be reduced. However, the decrease in negative pressure in the engine intake chamber will weaken the sealing of the intake chamber, and the engine oil will penetrate into the intake chamber or the cylinder, affecting the engine reliability.

[0004] Therefore, a crankcase ventilation system is urgently needed to solve the above technical problems. Summary of the invention

[0005] The purpose of the present invention is to provide a crankcase ventilation system, method and vehicle, which can avoid the reduction of negative pressure in the engine intake chamber and cause the weakening of the sealing when the engine is in post-treatment heating condition.

[0006] To achieve this object, the present invention adopts the following technical solutions:

[0007] In a first aspect, a crankcase ventilation system is provided, comprising:

[0008] Crankcase;

[0009] An oil-gas separator, wherein the inlet of the oil-gas separator is connected to the outlet of the crankcase, the liquid outlet of the oil-gas separator is connected to the oil pan, and the oil-gas separator has two gas outlets, one of which is at least connected to the outside atmosphere or the engine intake pipe;

[0010] A pressure regulating assembly comprises a vacuum pump, an air circuit solenoid valve and an air intake pipe connected in sequence, wherein the air inlet of the vacuum pump is connected to another air outlet of the oil-gas separator, the air intake pipe has a first air inlet and a second air inlet, the air outlet of the air intake pipe is connected to an air intake chamber of an engine, the first air inlet is connected to the air circuit solenoid valve, the second air inlet is connected to an air intake pipe of an engine, and the pressure regulating assembly is used to regulate the pressure in the crankcase so that the pressure in the crankcase is lower than the pressure in the air intake chamber of the engine.

[0011] As a preferred technical solution of the above-mentioned crankcase ventilation system, the pressure regulating assembly also includes a heating device, and the heating device is used to heat the air circuit solenoid valve and the vacuum pump.

[0012] As a preferred technical solution of the above crankcase ventilation system, the heating device is connected to the engine cooling water pipeline, the air circuit solenoid valve and the vacuum pump are both provided with cooling water channels, and the heating device is connected to the cooling water channel.

[0013] As a preferred technical solution of the above crankcase ventilation system, it also includes a pressure sensor, and the pressure sensor is used to detect the pressure in the crankcase.

[0014] As a preferred technical solution of the above crankcase ventilation system, it also includes a pressure controller, and the pressure controller is communicatively connected with at least the pressure sensor, the vacuum pump and the air circuit solenoid valve.

[0015] As a preferred technical solution of the above-mentioned crankcase ventilation system, the crankcase ventilation system also includes a throttle, the engine intake pipe is connected to the air inlet of the throttle, and the air outlet of the throttle is connected to the second air inlet of the intake pipe.

[0016] As a preferred technical solution of the above crankcase ventilation system, the crankcase ventilation system further includes a supercharger and a ventilation pipeline, the supercharger is arranged between the engine intake pipe and the throttle to connect the engine intake pipe and the throttle, the ventilation pipeline is respectively connected to one of the air outlets of the oil-gas separator and the air outlet of the intake boost valve, and the ventilation pipeline is also connected to the engine intake pipe; or,

[0017] The crankcase ventilation system also includes a one-way valve and a ventilation pipeline, wherein the air inlet of the one-way valve is connected to one of the outlets of the oil-gas separator, the air outlet of the one-way valve is connected to the air inlet of the ventilation pipeline, and the air outlet of the ventilation pipeline is connected to the outside atmosphere or the engine intake pipe.

[0018] In a second aspect, a crankcase ventilation system control method is provided, which is applied to the crankcase ventilation system described in any of the above schemes, and the crankcase ventilation system control method comprises the following steps:

[0019] When the engine is in a post-treatment heating condition, the pressure in the crankcase and the pressure in the intake chamber of the engine are obtained, and the difference between the pressure in the intake chamber of the engine and the pressure in the crankcase is obtained;

[0020] The pressure regulating component works according to the difference control.

[0021] As a preferred technical solution of the crankcase ventilation system control method, controlling the pressure regulating component according to the difference includes:

[0022] When the difference is less than or equal to the first preset difference, the vacuum pump is started, and the gas circuit solenoid valve between the vacuum pump and the intake pipe is opened, and the vacuum pump draws crankcase gas into the intake chamber until the difference reaches the second preset difference, the vacuum pump is turned off, and the gas circuit solenoid valve is closed;

[0023] When the difference is greater than or equal to a third preset difference, the gas circuit solenoid valve is opened and the vacuum pump is not started, until the difference reaches a second preset difference and the gas circuit solenoid valve is closed;

[0024] Among them, the first preset difference value<the second preset difference value<the third preset difference value.

[0025] A third party provides a vehicle comprising a crankcase ventilation system as described in any of the above schemes.

[0026] The present invention has at least the following beneficial effects:

[0027] The crankcase ventilation system and vehicle provided by the present invention include a crankcase, an oil-gas separator and a pressure regulating component, and the pressure regulating component includes a vacuum pump, an air circuit solenoid valve and an intake pipe connected in sequence. The pressure regulating component is used to adjust the negative pressure of the crankcase to achieve a large negative pressure in the crankcase. Under normal operating conditions of the engine, the air circuit solenoid valve is closed and only the original structure of the crankcase works. Under the post-processing heating conditions of the engine cold start and other conditions with a large throttle opening, the pressure regulating component will work to avoid the harm caused by the large negative pressure in the intake chamber. At this time, the air circuit solenoid valve is controlled to connect the air circuit between the crankcase and the intake pipe, and the vacuum pump is controlled to work, so as to control the pressure in the crankcase to decrease and the pressure in the intake chamber to increase, so as to achieve that the pressure in the crankcase is always less than the pressure in the cylinder, avoid oil seeping into the cylinder, causing oil burning, and ensure sealing.

[0028] The method provided by the present invention controls the operation of the air circuit solenoid valve and the vacuum pump to control and adjust the crankcase pressure by obtaining the difference pressure between the engine intake chamber pressure and the crankcase pressure during the post-processing heating condition of the engine cold start and other conditions with a large throttle opening, in order to avoid the harm caused by a large negative pressure in the intake chamber. This ensures that the crankcase pressure is still lower than the cylinder (i.e., intake chamber) pressure, thereby avoiding oil seepage into the cylinder and causing oil burning, and ensuring sealing. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments of the present invention. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the contents of the embodiments of the present invention and these drawings without paying any creative work.

[0030] Figure 1 A block diagram of a closed cycle crankcase ventilation system with post-supercharger air intake provided by an embodiment of the present invention;

[0031] Figure 2 A block diagram of a closed cycle crankcase ventilation system without a supercharger and air intake provided in an embodiment of the present invention;

[0032] Figure 3 A block diagram of an open cycle crankcase ventilation system provided by an embodiment of the present invention;

[0033] Figure 4 This is a flow chart of a crankcase ventilation system control method provided by an embodiment of the present invention.

[0034] In the figure:

[0035] 1. Crankcase; 2. Oil-gas separator; 3. Vacuum pump; 4. Air circuit solenoid valve; 5. Intake pipe; 6. Engine intake pipe; 7. Heating device; 8. Pressure controller; 9. Pressure sensor; 10. Throttle; 11. Supercharger; 12. Ventilation line; 13. Check valve; 15. Cylinder; 16. Intake chamber; 17. External atmosphere. DETAILED DESCRIPTION

[0036] The present invention will be further described in detail below in conjunction with the accompanying drawings and embodiments. It is to be understood that the specific embodiments described herein are only used to explain the present invention, rather than to limit the present invention. It should also be noted that, for ease of description, only parts related to the present invention, rather than all structures, are shown in the accompanying drawings.

[0037] In the description of the present invention, unless otherwise clearly specified and limited, the terms "connected", "connected", and "fixed" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0038] In the present invention, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may include that the first and second features are in direct contact, or may include that the first and second features are not in direct contact but are in contact through another feature between them. Moreover, a first feature being "above", "above" and "above" a second feature includes that the first feature is directly above and obliquely above the second feature, or simply indicates that the first feature is higher in level than the second feature. A first feature being "below", "below" and "below" a second feature includes that the first feature is directly below and obliquely below the second feature, or simply indicates that the first feature is lower in level than the second feature.

[0039] In the description of this embodiment, the terms "upper", "lower", "right", etc., directions or positional relationships are based on the directions or positional relationships shown in the drawings, and are only for the convenience of description and simplification of operation, rather than indicating or implying that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore cannot be understood as limiting the present invention. In addition, the terms "first" and "second" are only used to distinguish in the description and have no special meaning.

[0040] like Figure 1-Figure 3 As shown, the crankcase ventilation system includes a crankcase 1, an oil-gas separator 2 and a pressure regulating assembly, wherein the inlet of the oil-gas separator 2 is connected to the outlet of the crankcase 1, the inlet of the crankcase 1 is connected to the cylinder 15, the liquid outlet of the oil-gas separator 2 is connected to the oil pan, the oil-gas separator 2 has two air outlets, one of which is at least connected to the outside atmosphere 17 or the engine intake pipe 6; the pressure regulating assembly includes a vacuum pump 3, an air circuit solenoid valve 4 and an intake pipe 5 connected in sequence, a vacuum pump 3, an air circuit solenoid valve 4 and an intake pipe 5 connected in sequence, and a vacuum pump 3, an air circuit solenoid valve 4 and an intake pipe 5 connected in sequence. The air inlet of the pump 3 is connected to the other air outlet of the oil-gas separator 2, the air intake pipe 5 has a first air inlet and a second air inlet, the air outlet of the air intake pipe 5 is connected to the air intake chamber 16 of the engine, the first air inlet is connected to the air circuit solenoid valve 4, the second air inlet is connected to the engine intake pipe 6, the air inlet of the vacuum pump 3 is connected to the other air outlet of the oil-gas separator 2, and the pressure regulating assembly is used to adjust the pressure in the crankcase 1 so that the pressure in the crankcase 1 is lower than the pressure in the air intake chamber 16 of the engine.

[0041] The crankcase ventilation system provided in this embodiment includes a pressure regulating component, which is used to adjust the negative pressure of the crankcase 1 to achieve a large negative pressure in the crankcase 1. Under normal engine operating conditions, the air circuit solenoid valve 4 is closed and only the original structure of the crankcase 1 works. Under the post-processing heating conditions of the engine cold start and other conditions where the throttle 10 is opened at a large degree, in order to avoid the harm caused by the large negative pressure in the intake chamber 16, the pressure regulating component will take effect. At this time, the air circuit solenoid valve 4 is controlled to connect the air circuit between the crankcase 1 and the intake pipe 5, and the vacuum pump 3 is controlled to work, so as to control the pressure in the crankcase 1 to decrease and the pressure in the intake chamber 16 to increase, so as to achieve that the pressure in the crankcase 1 is still less than the pressure in the cylinder (i.e., the intake chamber 16), so as to avoid the oil from seeping into the cylinder and causing the oil to burn, thereby ensuring the sealing.

[0042] By setting a pressure regulating component, flexible control of a larger negative pressure of the crankcase 1 can be achieved, so that thermal management measures with lower intake negative pressure (post-processing heating conditions during engine cold start) can be implemented without the occurrence of oil seepage into the cylinder. This helps to increase the temperature of the post-processing and maintain the post-processing temperature during long-term low loads, thereby ensuring catalytic conversion efficiency and reducing pollutant emissions.

[0043] Since the added pressure regulating assembly is mainly operated in the post-processing heating condition of cold start and the condition of continuous low load, the gas temperature in the crankcase 1 is low at this time, and there is a risk of freezing in winter. Therefore, in some embodiments, the pressure regulating assembly also includes a heating device 7, which is used to heat the gas circuit solenoid valve 4 and the vacuum pump 3. In this way, the heating device 7 can be started when the pressure regulating assembly is working, thereby ensuring the normal operation of the gas circuit solenoid valve 4 and the vacuum pump 3, and avoiding the gas circuit solenoid valve 4 and the vacuum pump 3 from being blocked due to ice.

[0044] For example, the heating device 7 is connected to the engine cooling water pipeline, the gas circuit solenoid valve 4 and the vacuum pump 3 are both provided with cooling water channels, and the heating device 7 is connected to the cooling water channel, so that the heating device 7 can introduce the engine cooling water into the cooling water channel to heat the gas circuit solenoid valve 4 and the vacuum pump 3. The pressure regulating components and pipelines are heated by the engine cooling water to avoid freezing of the pressure regulating components and pipelines, and the heating device 7 does not need to be controlled. It should be noted that heating the pressure regulating components and pipelines during the post-processing heating condition other than the engine cold start will cause the intake temperature to increase slightly, but it has no effect on the post-processing heating condition of the engine cold start.

[0045] In some embodiments, in order to obtain the pressure in the crankcase 1 , the crankcase ventilation system further includes a pressure sensor 9 , which is used to detect the pressure in the crankcase 1 .

[0046] In some embodiments, in order to control the pressure regulating assembly according to the pressure in the crankcase 1 and the pressure in the intake chamber 16, the crankcase ventilation system further includes a pressure controller 8, which is at least in communication with the pressure sensor 9, the vacuum pump 3 and the gas circuit solenoid valve 4. After obtaining the pressure of the crankcase 1 detected by the pressure sensor 9, the pressure controller 8 controls the vacuum pump 3 and the gas circuit solenoid valve 4 to work, or the pressure controller 8 controls the gas circuit solenoid valve 4 to work.

[0047] In some embodiments, the crankcase ventilation system further includes an engine intake pipe 6 and a throttle valve 10, the engine intake pipe 6 is connected to the intake port of the throttle valve 10, and the outlet of the throttle valve 10 is connected to the second intake port of the intake pipe 5. The engine intake pipe 6 has an air filter to filter the gas.

[0048] In some embodiments, Figure 1 As shown, the crankcase ventilation system also includes a supercharger 11 and a ventilation line 12. The supercharger 11 is arranged between the engine intake pipe 6 and the throttle 10 to connect the engine intake pipe 6 and the throttle 10. The ventilation line 12 is respectively connected to one of the air outlets of the oil-gas separator 2 and the air outlet of the intake boost valve, and the ventilation line 12 is also connected to the engine intake pipe 6. In this embodiment, the engine is a diesel engine. For different types of diesel engines and ventilation routes, other structures are slightly different. For example, the crankcase ventilation system is a closed-loop structure with air intake after the supercharger 11, that is, the structure after the oil-gas separator 2 generally includes a one-way valve 13, an air intake pipe for taking air from the supercharger 11, a venturi device for high-velocity air intake, and an exhaust pipe before the supercharger 11.

[0049] In some embodiments, Figure 2 and Figure 3 As shown, the crankcase ventilation system also includes a one-way valve 13 and a ventilation pipeline 12, the air inlet of the one-way valve 13 is connected to one of the outlets of the oil-gas separator 2, the air outlet of the one-way valve 13 is connected to the air inlet of the ventilation pipeline 12, and the air outlet of the ventilation pipeline 12 is connected to the outside atmosphere 17 or the engine intake pipe 6. For example, the crankcase ventilation system does not have a closed-loop structure for taking air after the supercharger 11, and generally only has an exhaust pipeline connected to the front of the supercharger 11 after the oil-gas separator 2; when the crankcase ventilation system is an open cycle, there is also only one ventilation pipeline 12 connected to the atmosphere after the oil-gas separator 2.

[0050] like Figure 2 As shown, for the structure without supercharger rear air intake, since there is no one-way valve 13 in the crankcase ventilation system, when the crankcase 1 controls a large negative pressure, it will inhale air from the atmosphere or from before the supercharger 11, resulting in the pressure being unable to drop. It is also necessary to add a one-way valve 13 to the second air outlet of the oil-gas separator 2.

[0051] The present invention provides a crankcase ventilation system control method, which is applied to a crankcase ventilation system, such as Figure 4 As shown, the crankcase ventilation system control method includes the following steps:

[0052] S101, when the engine is in a post-treatment heating condition, obtaining the pressure in the crankcase 1 and the pressure in the engine intake chamber 16, and obtaining the difference between the pressure in the engine intake chamber 16 and the pressure in the crankcase 1;

[0053] S102, controlling the pressure regulating component to operate according to the difference.

[0054] In the post-processing heating conditions of the engine cold start and other conditions where the throttle 10 is opened at a large degree, in order to avoid the harm caused by the large negative pressure in the intake chamber 16, the difference pressure between the pressure of the engine intake chamber 16 and the pressure in the crankcase 1 is obtained to control the operation of the air circuit solenoid valve 4 and the vacuum pump 3 to control and adjust the crankcase 1 pressure, so that the crankcase 1 pressure is still lower than the pressure in the cylinder (i.e., the intake chamber 16), thereby avoiding oil from seeping into the cylinder and causing oil burning, and ensuring sealing.

[0055] In some embodiments, controlling the pressure regulating component to operate according to the difference includes:

[0056] S1021, when the difference is less than or equal to the first preset difference, the vacuum pump 3 is started, and the gas circuit solenoid valve 4 between the vacuum pump 3 and the intake pipe 5 is opened, and the vacuum pump 3 extracts the gas from the crankcase 1 into the intake chamber 16, until the difference reaches the second preset difference, the vacuum pump 3 is turned off, and the gas circuit solenoid valve 4 is closed;

[0057] S1022, when the difference is greater than or equal to the third preset difference, the gas circuit solenoid valve 4 is opened, and the vacuum pump 3 is not started, until the difference is the second preset difference, and the gas circuit solenoid valve 4 is closed;

[0058] Among them, the first preset difference value<the second preset difference value<the third preset difference value.

[0059] The pressure controller 8 stores the target value of the pressure difference between the crankcase 1 pressure and the intake chamber 16 pressure under each speed and torque condition. There are three preset differences, namely the first preset difference, the second preset difference and the third preset difference, wherein the first preset difference is the lower limit, the second preset difference is the maintenance value, the third preset difference is the upper limit, and the first preset difference < the second preset difference < the third preset difference.

[0060] For example, the first preset difference is 3kPa, the second preset difference is 9kPa, and the third preset difference is 15kPa. The pressure controller 8 has three control states, namely increasing the pressure difference, reducing the pressure difference, and maintaining the pressure difference. When increasing the pressure difference, the vacuum pump 3 is started, and the air circuit solenoid valve 4 between the vacuum pump 3 and the intake pipe 5 is opened, and the vacuum pump 3 extracts the gas from the crankcase 1 into the intake chamber 16 to increase the pressure difference; when reducing the pressure difference, the air circuit solenoid valve 4 is opened, but the vacuum pump 3 is not started, and the pressure difference between the intake pipe 5 and the crankcase 1 pushes the intake air into the crankcase 1 to reduce the pressure difference; when maintaining the pressure difference, the vacuum pump 3 is stopped and the air circuit solenoid valve 4 is closed, the gas in the crankcase 1 cannot be discharged, and the pressure difference is maintained. When the crankcase 1 starts working normally, the default setting is to maintain the pressure difference. When the pressure difference between the intake chamber 16 and the crankcase 1 is lower than 3kPa (the first preset difference), it jumps to the pressure difference increase state. At this time, the vacuum pump 3 and the air circuit solenoid valve 4 are opened to transport the crankcase 1 gas to the intake pipe 5. When the pressure difference between the intake pressure and the crankcase 1 reaches 9kPa (the second preset difference), it returns to maintaining the pressure difference. At this time, the air circuit solenoid valve 4 and the vacuum pump 3 are closed. Due to the existence of the one-way valve 13, the normal crankcase ventilation structure cannot transport the gas to the crankcase 1, and the pressure of the crankcase 1 is basically maintained; when the pressure difference between the intake pressure and the crankcase 1 is too large, exceeding 15kPa (the third preset difference), the pressure difference is reduced. At this time, the air circuit solenoid valve 4 is opened, and the gas enters the crankcase 1 from the intake pipe 5. After it is lower than 9kPa (the second preset difference), it jumps to maintain the pressure difference and closes the air circuit solenoid valve 4.

[0061] An embodiment of the present invention provides a vehicle, comprising the crankcase ventilation system provided by the present invention.

[0062] Since the vehicle includes a crankcase ventilation system, the crankcase ventilation system includes a pressure regulating component, and the pressure regulating component is used to adjust the negative pressure of the crankcase 1 to achieve a large negative pressure in the crankcase 1. Under normal engine operating conditions, the air circuit solenoid valve 4 is closed, and only the original structure of the crankcase 1 works; under the post-processing heating conditions of the engine cold start and other conditions where the throttle 10 is opened at a large degree, in order to avoid the harm caused by the large negative pressure in the intake chamber 16, the pressure regulating component will take effect. At this time, the air circuit solenoid valve 4 is controlled to connect the air circuit between the crankcase 1 and the intake pipe 5, and the vacuum pump 3 is controlled to work to control the pressure of the crankcase 1, so that the pressure of the crankcase 1 is still less than the pressure in the cylinder (i.e., the intake chamber 16), to avoid oil seeping into the cylinder, causing oil burning, and to ensure sealing.

[0063] Since the crankcase ventilation system described above is included, the vehicle according to the embodiment of the present invention has all the advantages and beneficial effects of the above embodiments, which will not be described in detail herein.

[0064] Compared with the prior art, the benefits of the present invention are:

[0065] (1) The present invention controls the crankcase 1 to achieve a relatively large negative pressure by adding a vacuum pump 3 and an air circuit solenoid valve 4, thereby achieving a negative pressure of the crankcase 1 relative to the intake chamber 16 under the post-treatment heating condition of the engine cold start, thereby preventing the oil from seeping into the cylinder under the severe post-treatment heating condition of the engine cold start, thereby preventing the oil from burning.

[0066] (2) On the basis of not affecting the crankcase ventilation system, a pressure regulating component is added. Under the post-treatment heating condition of the engine cold start, the pressure difference between the crankcase 1 and the intake chamber 16 can be controlled according to a preset value, and a heating device 7 is provided to prevent freezing in winter.

[0067] In addition, the above are only preferred embodiments of the present invention and the technical principles used. Those skilled in the art will understand that the present invention is not limited to the specific embodiments described herein, and that various obvious changes, readjustments and substitutions can be made by those skilled in the art without departing from the scope of protection of the present invention. Therefore, although the present invention has been described in more detail through the above embodiments, the present invention is not limited to the above embodiments, and may also include more other equivalent embodiments without departing from the concept of the present invention, and the scope of the present invention is determined by the scope of the appended claims.

Claims

1. A crankcase ventilation system, characterized in that: include: Crankcase (1); An oil-gas separator (2), wherein the inlet of the oil-gas separator (2) is connected to the outlet of the crankcase (1), the liquid outlet of the oil-gas separator (2) is connected to the oil pan, and the oil-gas separator (2) has two gas outlets, one of which is connected to at least the outside atmosphere (17) or the engine intake pipe (6); A pressure regulating assembly comprises a vacuum pump (3), an air circuit solenoid valve (4) and an air intake pipe (5) connected in sequence, wherein the air intake of the vacuum pump (3) is connected to another air outlet of the oil-gas separator (2), the air intake pipe (5) has a first air intake and a second air intake, the air outlet of the air intake pipe (5) is connected to an air intake chamber (16) of an engine, the first air intake is connected to the air circuit solenoid valve (4), the second air intake is connected to an air intake pipe (6) of the engine, and the pressure regulating assembly is used to regulate the pressure in the crankcase (1) so that the pressure in the crankcase (1) is less than the pressure in the air intake chamber (16) of the engine.

2. The crankcase ventilation system according to claim 1, characterized in that The pressure regulating assembly further comprises a heating device (7), wherein the heating device (7) is used to heat the gas circuit solenoid valve (4) and the vacuum pump (3).

3. The crankcase ventilation system according to claim 2, characterized in that: The heating device (7) is connected to the engine cooling water pipeline, the gas circuit solenoid valve (4) and the vacuum pump (3) are both provided with cooling water channels, and the heating device (7) is in communication with the cooling water channels.

4. The crankcase ventilation system according to claim 1, characterized in that It also comprises a pressure sensor (9), wherein the pressure sensor (9) is used to detect the pressure in the crankcase (1).

5. The crankcase ventilation system according to claim 4, characterized in that It also includes a pressure controller, which is communicatively connected to at least the pressure sensor (9), the vacuum pump (3) and the gas circuit solenoid valve (4).

6. The crankcase ventilation system according to claim 1, characterized in that The crankcase ventilation system further comprises a throttle valve (10), the engine air intake pipe (6) is connected to the air intake port of the throttle valve (10), and the air outlet of the throttle valve (10) is communicated with the second air intake port of the air intake pipe (5).

7. The crankcase ventilation system according to claim 6, characterized in that The crankcase ventilation system further comprises a supercharger (11) and a ventilation pipeline (12), wherein the supercharger (11) is arranged between the engine intake pipe (6) and the throttle valve (10) to connect the engine intake pipe (6) and the throttle valve (10), and the ventilation pipeline (12) is respectively connected to one of the air outlets of the oil-gas separator (2) and the air outlet of the intake boost valve, and the ventilation pipeline (12) is also connected to the engine intake pipe (6); or, The crankcase ventilation system further comprises a one-way valve (13) and a ventilation pipeline (12), wherein an air inlet of the one-way valve (13) is connected to one of the outlets of the oil-gas separator (2), an air outlet of the one-way valve (13) is communicated with an air inlet of the ventilation pipeline (12), and an air outlet of the ventilation pipeline (12) is communicated with the outside atmosphere (17) or the engine air intake pipe (6).

8. A crankcase ventilation system control method, characterized in that: Applied to the crankcase ventilation system according to any one of claims 1 to 7, the crankcase ventilation system control method comprises the following steps: When the engine is in a post-treatment heating condition, the pressure in the crankcase (1) and the pressure in the intake chamber (16) of the engine are obtained, and the difference between the pressure in the intake chamber (16) of the engine and the pressure in the crankcase (1) is obtained; The pressure regulating component works according to the difference control.

9. The crankcase ventilation system control method according to claim 8, characterized in that: The work of the pressure regulating component based on the differential control includes: When the difference is less than or equal to a first preset difference, the vacuum pump (3) is started, and the gas circuit solenoid valve (4) between the vacuum pump (3) and the intake pipe (5) is opened, and the vacuum pump (3) extracts the crankcase (1) gas into the intake chamber (16), until the difference reaches a second preset difference, the vacuum pump (3) is turned off, and the gas circuit solenoid valve (4) is closed; When the difference is greater than or equal to a third preset difference, the gas circuit solenoid valve (4) is opened and the vacuum pump (3) is not started until the difference reaches a second preset difference and the gas circuit solenoid valve (4) is closed; Among them, the first preset difference value<the second preset difference value<the third preset difference value.

10. A vehicle, characterized in that: Comprising the crankcase ventilation system of claims 1-7.

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