阅读说明：本技术 一种曲轴箱通风控制方法及系统 (Crankcase ventilation control method and system ) 是由 张培亮 许雨涛 王超 于 2019-10-25 设计创作，主要内容包括：本发明公开了一种曲轴箱通风控制方法及系统,曲轴箱通风控制方法应用于曲轴箱通风控制系统,其中,曲轴箱通风控制系统包括曲轴箱、射流阀、曲轴箱强制通风阀和控制器；射流阀和曲轴箱强制通风阀均与控制器电连接；曲轴箱的一端与射流阀连通,曲轴箱的另一端与曲轴箱强制通风阀连通,所述方法包括：获取发动机的转速；比较转速和第一预设值；当转速小于第一预设值时,控制曲轴箱强制通风阀开启,控制射流阀关闭；当转速不小于所述第一预设值时,控制射流阀开启,控制曲轴箱强制通风阀关闭。本发明通过控制射流阀和曲轴箱强制通风阀的开启或关闭,使曲轴箱内的气体能够重新进行燃烧,解决了增压发动机在高速运转时,曲轴箱内的气体不易排出的问题。(The invention discloses a crankcase ventilation control method and a crankcase ventilation control system, wherein the crankcase ventilation control method is applied to the crankcase ventilation control system, and the crankcase ventilation control system comprises a crankcase, a jet valve, a crankcase forced ventilation valve and a controller; the jet valve and the crankcase forced ventilation valve are electrically connected with the controller; one end of the crankcase is communicated with the jet valve, and the other end of the crankcase is communicated with the positive crankcase ventilation valve, and the method comprises the following steps: acquiring the rotating speed of an engine; comparing the rotating speed with a first preset value; when the rotating speed is less than a first preset value, controlling a forced ventilation valve of a crankcase to be opened and controlling a jet valve to be closed; and when the rotating speed is not less than the first preset value, controlling the jet valve to be opened and controlling the crankcase forced ventilation valve to be closed. The invention controls the opening or closing of the jet valve and the crankcase forced ventilation valve to ensure that the gas in the crankcase can be combusted again, thereby solving the problem that the gas in the crankcase is difficult to discharge when the supercharged engine runs at high speed.)

1. The crankcase ventilation control method is applied to a crankcase ventilation control system, wherein the crankcase ventilation control system comprises a crankcase, a jet valve, a positive crankcase ventilation valve and a controller; the jet valve and the crankcase forced ventilation valve are electrically connected with the controller; one end of the crankcase is communicated with the jet valve, and the other end of the crankcase is communicated with a positive crankcase ventilation valve, and the method comprises the following steps:

acquiring the rotating speed of an engine;

comparing the rotating speed with a first preset value;

when the rotating speed is less than a first preset value, controlling the crankcase forced ventilation valve to be opened, and controlling the jet valve to be closed so as to discharge gas in the crankcase through the crankcase forced ventilation valve;

and when the rotating speed is not less than the first preset value, controlling the jet valve to be opened, and controlling the crankcase forced ventilation valve to be closed so as to discharge the gas in the crankcase through the jet valve.

2. The crankcase ventilation control method according to claim 1, wherein when the rotation speed is not less than the first preset value, controlling the fluidic valve to open comprises:

acquiring the pressure of the crankcase;

comparing the pressure with a preset pressure value;

when the pressure is smaller than the preset pressure value, comparing the rotating speed with a second preset value and a third preset value;

when the rotating speed is not greater than a second preset value, controlling the opening degree of the jet valve to be a first value;

when the rotating speed is between the second preset value and the third preset value, controlling the opening degree of the jet valve to be a second value;

when the rotating speed is not less than the third preset value, controlling the opening degree of the jet valve to be a third value; wherein the second preset value is smaller than the third preset value.

3. A crankcase ventilation control method according to claim 2, wherein the comparing the pressure with a preset pressure value comprises:

and when the pressure of the crankcase is not less than the preset pressure value, controlling the opening of the jet valve to be a third value.

4. The crankcase ventilation control method according to claim 3, wherein the crankcase ventilation control system further comprises a supercharger, one end of the supercharger is communicated with the jet valve, the other end of the supercharger is communicated with the crankcase, when the rotating speed is not less than the first preset value, the jet valve is controlled to be opened, and the crankcase forced ventilation valve is controlled to be closed, the method comprising:

and when the rotating speed is not less than a first preset value, controlling the crankcase forced ventilation valve to be closed, and controlling the jet valve and the supercharger to work so that the gas in the crankcase enters the supercharger through the jet valve, and enters an intake manifold after being supercharged by the supercharger.

5. A crankcase ventilation control system for implementing the crankcase ventilation control method according to any one of claims 1-4, wherein the system comprises a crankcase (1), a jet valve (6), a positive crankcase ventilation valve (5) and a controller;

the jet valve (6) and the crankcase forced ventilation valve (5) are both electrically connected with the controller, and the jet valve (6) and the crankcase forced ventilation valve (5) are both communicated with the crankcase (1);

the controller is configured to: the method comprises the steps of obtaining the rotating speed of an engine, comparing the rotating speed of the engine with a first preset value, controlling a positive crankcase ventilation valve (5) to be opened and controlling a jet valve (6) to be closed when the rotating speed is smaller than the first preset value, and discharging gas in a crankcase (1) through the positive crankcase ventilation valve (5); and when the rotating speed is not less than the first preset value, controlling the jet valve (6) to be opened, and controlling the crankcase forced ventilation valve (5) to be closed so as to discharge the gas in the crankcase (1) through the jet valve (6).

6. A crankcase ventilation control system according to claim 5, further comprising a first conduit (4) and a second conduit (8), the inlet end of the first conduit (4) communicating with the inlet end of the second conduit (8); the jet valve (6) is arranged on a first pipeline (4), the inlet end of the first pipeline (4) is communicated with the inlet end of a supercharger (7), and the outlet end of the first pipeline (4) is communicated with the outlet end of the supercharger (7);

the entry end of second pipeline (8) with booster (7) intercommunication, the exit end and air intake manifold (2) intercommunication of second pipeline (8), be provided with throttle valve (9) and intercooler (10) on second pipeline (8), the entry end of intercooler (10) with booster (7) intercommunication, the exit end of intercooler (10) with throttle valve (9) intercommunication.

7. A crankcase ventilation control system according to claim 6, further comprising a filtering device, wherein the filtering device comprises an air filter (11), a first oil-gas separator (12), a second oil-gas separator (13) and a third oil-gas separator (14), an inlet end of the air filter (11) is communicated with an outlet end of the supercharger (7), an outlet end of the air filter (11) is communicated with the first oil-gas separator (12), one end of the second oil-gas separator (13) is communicated with the first oil-gas separator (12), and the other end of the second oil-gas separator (13) is communicated with the third oil-gas separator (14).

8. A crankcase ventilation control system according to claim 7, further comprising an intake manifold (2) and an air supply pipe (3), one end of the air supply pipe (3) being in communication with the atmosphere, the other end of the air supply pipe (3) being in communication with the supercharger (7), the intake manifold (2) being in communication with the crankcase ventilation valve (5).

9. A crankcase ventilation control system according to claim 8, wherein the third air-oil separator (14) comprises a third outlet end, a fourth outlet end and a second inlet end, the second inlet end being in communication with the second air-oil separator (13), the third outlet end being in communication with the intake manifold (2) via a crankcase ventilation valve (5), the fourth outlet end being in communication with the jet valve (6).

10. A crankcase ventilation control system according to claim 9, wherein the jet valve (6) comprises a first outlet end, a second outlet end and a first inlet end, the second outlet end communicating with the crankcase (1), a partition being arranged between the first inlet end and the second outlet end for opening or closing the jet valve (6) and enabling adjustment of the flow of gas through the jet valve (6).

Technical Field

The invention relates to the technical field of automobiles, in particular to a crankcase ventilation control method and system.

Background

Along with the gradual increase of the usage amount of automobiles, the pollution of automobile exhaust is more and more serious, and the pollution of the automobile exhaust is limited by the national six-emission regulation which is comprehensively implemented in order to reduce the pollution. The leakage of waste gas in the crankcase greatly increases the pollution of automobile tail gas, leaked gas from the combustion of an engine can permeate into the crankcase of the engine from a piston ring of the engine, and if the crankcase cannot introduce the leaked gas into an air inlet manifold in time, the pressure in the crankcase is increased, so that the oil seal of the crankcase can be leaked.

In the prior art, in order to solve the crankcase ventilation problem, positive crankcase ventilation systems have been added, which are capable of recirculating these blow-by gases through a valve to the intake manifold where it is pumped back into the cylinder for another opportunity for combustion. When the supercharged engine is idling, the air pressure in the intake manifold is lower than the air pressure in the crankcase, and it is this lower pressure that draws blow-by gases through the crankcase ventilation valve and into the intake manifold. When supercharged engine was in the heavy load operating mode, the booster began to intervene work, and intake manifold internal pressure became malleation by the negative pressure this moment, thereby for preventing that high-pressure gas from getting into the crankcase and causing crankcase pressure to rise and produce the oil blanket and leak the scheduling problem, closed crankcase forced ventilation valve, and the unable intake manifold that gets into of gas in the crankcase leads to the unable in time discharge of waste gas in the crankcase.

Based on the defects in the prior art, a crankcase ventilation control method and system are urgently needed to be researched to solve the problems.

Disclosure of Invention

In order to solve the technical problem, the invention discloses a crankcase ventilation control method and a crankcase ventilation control system.

The invention discloses a crankcase ventilation control method, which is applied to a crankcase ventilation control system, wherein the crankcase ventilation control system comprises a crankcase, a jet valve, a crankcase forced ventilation valve and a controller; the jet valve and the crankcase forced ventilation valve are electrically connected with the controller; one end of the crankcase is communicated with the jet valve, and the other end of the crankcase is communicated with a positive crankcase ventilation valve, and the method comprises the following steps:

acquiring the rotating speed of an engine;

comparing the rotating speed with a first preset value;

when the rotating speed is less than a first preset value, controlling the crankcase forced ventilation valve to be opened, and controlling the jet valve to be closed so as to discharge gas in the crankcase through the crankcase forced ventilation valve;

and when the rotating speed is not less than the first preset value, controlling the jet valve to be opened, and controlling the crankcase forced ventilation valve to be closed so as to discharge the gas in the crankcase through the jet valve.

Further, when the rotating speed is not less than the first preset value, controlling the jet valve to open comprises:

acquiring the pressure of the crankcase;

comparing the pressure with a preset pressure value;

when the pressure is smaller than the preset pressure value, comparing the rotating speed with a second preset value and a third preset value;

when the rotating speed is not greater than a second preset value, controlling the opening degree of the jet valve to be a first value;

when the rotating speed is between the second preset value and the third preset value, controlling the opening degree of the jet valve to be a second value;

when the rotating speed is not less than the third preset value, controlling the opening degree of the jet valve to be a third value; wherein the second preset value is smaller than the third preset value.

Further, the comparing the pressure with a preset pressure value comprises:

and when the pressure of the crankcase is not less than the preset pressure value, controlling the opening of the jet valve to be a third value.

Further, the crankcase ventilation control system further comprises a supercharger, one end of the supercharger is communicated with the jet valve, the other end of the supercharger is communicated with the crankcase, when the rotating speed is not less than the first preset value, the jet valve is controlled to be opened, and the crankcase forced ventilation valve is controlled to be closed, wherein the step of:

and when the rotating speed is not less than a first preset value, controlling the crankcase forced ventilation valve to be closed, and controlling the jet valve and the supercharger to work so that the gas in the crankcase enters the supercharger through the jet valve, and enters an intake manifold after being supercharged by the supercharger.

The invention also provides a crankcase ventilation control system, which is used for realizing the crankcase ventilation control method, and the system comprises: the device comprises a crankcase, a jet valve, a crankcase forced ventilation valve and a controller;

the jet valve and the crankcase forced ventilation valve are both electrically connected with the controller, and both the jet valve and the crankcase forced ventilation valve are communicated with the crankcase;

the controller is configured to: the method comprises the steps of obtaining the rotating speed of an engine, comparing the rotating speed of the engine with a first preset value, controlling the crankcase forced ventilation valve to be opened and controlling the jet valve to be closed when the rotating speed is smaller than the first preset value, and discharging gas in the crankcase through the crankcase forced ventilation valve; and when the rotating speed is not less than the first preset value, controlling the jet valve to be opened, and controlling the crankcase forced ventilation valve to be closed so as to discharge the gas in the crankcase through the jet valve.

The device further comprises a first pipeline and a second pipeline, wherein the inlet end of the first pipeline is communicated with the inlet end of the second pipeline; the jet valve is arranged on a first pipeline, the inlet end of the first pipeline is communicated with the inlet end of the supercharger, and the outlet end of the first pipeline is communicated with the outlet end of the supercharger;

the inlet end of the second pipeline is communicated with the supercharger, the outlet end of the second pipeline is communicated with the intake manifold, a throttle valve and an intercooler are arranged on the second pipeline, the inlet end of the intercooler is communicated with the supercharger, and the outlet end of the intercooler is communicated with the throttle valve.

The air purifier comprises a supercharger, a first oil-gas separator, a second oil-gas separator and a third oil-gas separator, wherein the inlet end of the supercharger is communicated with the inlet end of the air purifier, the outlet end of the supercharger is communicated with the first oil-gas separator, one end of the second oil-gas separator is communicated with the first oil-gas separator, and the other end of the second oil-gas separator is communicated with the third oil-gas separator.

Further, the system also comprises an air inlet manifold and an air supplementing pipe, wherein one end of the air supplementing pipe is communicated with the atmosphere, the other end of the air supplementing pipe is communicated with the supercharger, and the air inlet manifold is communicated with the crankcase forced ventilation valve.

Further, the third oil-gas separator comprises a third outlet end, a fourth outlet end and a second inlet end, the second inlet end is communicated with the second oil-gas separator, the third outlet end is communicated with the air inlet manifold through a crankcase forced ventilation valve, and the fourth outlet end is communicated with the jet valve.

Further, the jet valve comprises a first outlet end, a second outlet end and a first inlet end, the second outlet end is communicated with the crankcase, a partition plate is arranged between the first inlet end and the second outlet end, and the partition plate is used for opening or closing the jet valve and can adjust the flow of the gas passing through the jet valve.

The embodiment of the invention has the following beneficial effects:

the invention controls the opening or closing of the jet valve and the crankcase forced ventilation valve to ensure that the gas in the crankcase can enter the intake manifold again for combustion, thereby solving the problem that the gas in the crankcase is not easy to discharge when the supercharged engine runs at high speed and achieving good ventilation effect of the crankcase.

Drawings

In order to more clearly illustrate the technical solution of the present invention, the drawings used in the description of the embodiment or the prior art will be briefly described below. It is obvious that the drawings in the following description are only some embodiments of the invention, and that for a person skilled in the art, other drawings can be derived from them without inventive effort.

FIG. 1 is a flowchart of a crankcase ventilation control method according to an embodiment of the invention;

fig. 2 is a schematic structural diagram of a crankcase ventilation control system according to an embodiment of the invention.

Wherein the reference numerals in the figures correspond to:

1-a crankcase; 2-an intake manifold; 3-air supplement pipe; 4-a first pipeline; 5-crankcase forced ventilation valve; 6-a fluidic valve; 7-a supercharger; 8-a second pipeline; 9-a throttle valve; 10-an intercooler; 11-an air filter; 12-a first oil-gas separator; 13-a second oil-gas separator; 14-third oil-gas separator.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be obtained by a person skilled in the art without any inventive step based on the embodiments of the present invention, are within the scope of the present invention.

It should be noted that the terms "first," "second," and the like in the description and claims of the present invention and in the drawings described above are used for distinguishing between similar elements and not necessarily for describing a particular sequential or chronological order. It is to be understood that the data so used is interchangeable under appropriate circumstances such that the embodiments of the invention described herein are capable of operation in sequences other than those illustrated or described herein. Furthermore, the terms "comprises," "comprising," and "having," and any variations thereof, are intended to cover a non-exclusive inclusion, such that a process, method, system, article, or apparatus that comprises a list of steps or elements is not necessarily limited to those steps or elements expressly listed, but may include other steps or elements not expressly listed or inherent to such process, method, article, or apparatus.

The existing crankcase ventilation control system has the following defects: along with supercharged engine rotational speed increases, when supercharged engine was in the heavy load operating mode, the booster began to intervene work, and intake manifold internal pressure became malleation by the negative pressure this moment, thereby for preventing that high-pressure gas from getting into the crankcase and causing the crankcase pressure to rise and produce the oil blanket and leak the scheduling problem, closes crankcase forced ventilation valve, and the unable intake manifold that gets into of gas in the crankcase leads to the unable in time discharge of waste gas in the crankcase.

In order to overcome the defects of the prior art, embodiments of the present invention provide a crankcase ventilation control method and system, which control the opening or closing of a jet valve and a crankcase forced ventilation valve to enable gas in a crankcase to re-enter an intake manifold for combustion, thereby solving the problem that gas in the crankcase is not easy to be discharged when a supercharged engine is in high-speed operation, and achieving a good ventilation effect of the crankcase.

Referring to fig. 1-2, the present embodiment provides a crankcase ventilation control method and system, wherein the crankcase ventilation control method is applied to a crankcase ventilation control system, wherein the crankcase ventilation control system comprises a crankcase, a jet valve, a positive crankcase ventilation valve and a controller; the jet valve and the crankcase forced ventilation valve are electrically connected with the controller; one end of the crankcase is communicated with the jet valve, and the other end of the crankcase is communicated with a positive crankcase ventilation valve, and the method comprises the following steps:

s1: acquiring the rotating speed of an engine;

and acquiring the rotating speed of the engine according to a rotating speed sensor, wherein the rotating speed sensor is arranged in the engine.

S2: comparing the rotating speed with a first preset value;

it should be noted that the first preset value is a critical value for closing the positive crankcase ventilation valve, when the rotation speed is greater than the first preset value, since the engine is required to run at a high speed to generate sufficient torque, at this time, the pressure in the intake manifold is much greater than the pressure in the crankcase, and in order to prevent the oil seal of the crankcase from being failed due to the excessive pressure after the crankcase is communicated with the intake manifold, the positive crankcase ventilation valve is in a closed state, and the crankcase cannot be communicated with the intake manifold.

S3: when the rotating speed is less than a first preset value, controlling the crankcase forced ventilation valve to be opened, and controlling the jet valve to be closed so as to discharge gas in the crankcase through the crankcase forced ventilation valve;

specifically, at this time, the pressure difference between the crankcase and the intake manifold is not large, and the crankcase and the intake manifold can communicate with each other.

S4: and when the rotating speed is not less than the first preset value, controlling the jet valve to be opened, and controlling the crankcase forced ventilation valve to be closed so as to discharge the gas in the crankcase through the jet valve.

Specifically, at this time, the pressure difference between the crankcase and the intake manifold is large, and the crankcase and the intake manifold cannot be communicated with each other, so that the gas in the crankcase enters the supercharger by using the jet valve and then enters the intake manifold again for combustion; by controlling the opening or closing of the jet valve and the crankcase forced ventilation valve, gas in the crankcase can enter the intake manifold again for combustion, the problem that the gas in the crankcase is not easy to discharge when the supercharged engine runs at a high speed is solved, and the good ventilation effect of the crankcase is achieved.

Preferably, when the rotating speed is not less than the first preset value, controlling the jet valve to open comprises:

acquiring the pressure of the crankcase;

and acquiring the pressure of the crankcase according to the pressure sensor, wherein the pressure sensor is electrically connected with the controller, and the pressure sensor can transmit a pressure signal of the crankcase to the controller.

Comparing the pressure with a preset pressure value;

when the pressure is smaller than the preset pressure value, comparing the rotating speed with a second preset value and a third preset value;

when the rotating speed is not greater than a second preset value, controlling the opening degree of the jet valve to be a first value;

when the rotating speed is between the second preset value and the third preset value, controlling the opening degree of the jet valve to be a second value;

when the rotating speed is not less than the third preset value, controlling the opening degree of the jet valve to be a third value; wherein the second preset value is smaller than the third preset value.

Specifically, the first value is greater than the second value, the second value is greater than the third value, when the aperture of the jet valve is the first value, the aperture of the jet valve is the largest, the greater the rotation speed of the engine is, the smaller the aperture of the jet valve is, when the aperture of the jet valve is the smallest, the vacuum degree generated after the gas passes through the jet valve is the largest, the jet valve is added, and the gas flow of the jet valve is controlled by using a controller, so that the accurate control of the pressure of the crankcase is realized, and the gas in the crankcase can realize good ventilation effect.

Specifically, the first preset value, the second preset value and the third preset value are preset values set according to the rotating speed of the engine, and the second preset value is larger than the first preset value and smaller than the third preset value.

Preferably, said comparing said pressure with a preset pressure value comprises:

and when the pressure of the crankcase is not less than the preset pressure value, controlling the opening of the jet valve to be a third value.

Specifically, the fourth preset value is a maximum pressure value that the crankcase can bear, and when the pressure in the crankcase reaches the fourth preset value, the opening degree of the jet valve is directly controlled to be a third value without considering the rotation speed of the engine; when the pressure in the crankcase reaches the fourth preset value, the influence on the crankcase is large, so that the pressure in the crankcase should be reduced rapidly, the opening degree of the jet valve is opened to a third value, the vacuum degree generated by the jet valve is larger, gas in the crankcase enters the supercharger more rapidly, the opening degree of the jet valve is controlled by the controller, accurate control on the pressure of the crankcase is achieved, and good ventilation effect can be achieved for the gas in the crankcase.

Preferably, the crankcase ventilation control system further includes a supercharger, one end of the supercharger is communicated with the jet valve, the other end of the supercharger is communicated with the crankcase, the controlling of the jet valve to be opened and the controlling of the crankcase forced ventilation valve to be closed when the rotation speed is not less than the first preset value includes:

and when the rotating speed is not less than a first preset value, controlling the crankcase forced ventilation valve to be closed, and controlling the jet valve and the supercharger to work so that the gas in the crankcase enters the supercharger through the jet valve, and enters an intake manifold after being supercharged by the supercharger.

Specifically, the first value is greater than the second value, the second value is greater than the third value, when the aperture of the jet valve is the first value, the aperture of the jet valve is the largest, the greater the rotation speed of the engine is, the smaller the aperture of the jet valve is, when the aperture of the jet valve is the smallest, the vacuum degree generated after the gas passes through the jet valve is the largest, the jet valve is added, and the gas flow of the jet valve is controlled by using a controller, so that the accurate control of the pressure of the crankcase is realized, and the gas in the crankcase can realize good ventilation effect.

Specifically, the first preset value, the second preset value and the third preset value are preset values set according to the rotating speed of the engine, and the second preset value is larger than the first preset value and smaller than the third preset value.

The invention also provides a crankcase ventilation control system, which is used for realizing the crankcase ventilation control method, and the system comprises: the device comprises a crankcase 1, a jet valve 6, a crankcase forced ventilation valve 5 and a controller;

the jet valve 6 and the crankcase forced ventilation valve 5 are both electrically connected with the controller, and the jet valve 6 and the crankcase forced ventilation valve 5 are both communicated with the crankcase 1;

the controller is configured to: the method comprises the steps of obtaining the rotating speed of an engine, comparing the rotating speed of the engine with a first preset value, controlling the crankcase forced ventilation valve 5 to be opened when the rotating speed is smaller than the first preset value, and controlling the jet valve 6 to be closed so as to discharge gas in the crankcase 1 through the crankcase forced ventilation valve 5; when the rotating speed is not less than the first preset value, controlling the jet valve 6 to be opened, and controlling the crankcase forced ventilation valve 5 to be closed so as to discharge the gas in the crankcase 1 through the jet valve 6; by controlling the opening or closing of the jet valve and the crankcase forced ventilation valve, gas in the crankcase can enter the intake manifold again for combustion, the problem that the gas in the crankcase 1 is not easy to discharge when the engine runs at a high speed is solved, and the good ventilation effect of the crankcase 1 is realized.

Specifically, the air supply pipe 3 is used for introducing gas into the intake manifold for combustion, the supercharger 7 is used for increasing the pressure entering from the air supply pipe 3, the gas enters the first pipeline 4 after being supercharged by the supercharger 7, a negative pressure condition is generated in the first pipeline 4 through high-speed flow of the gas, the jet valve 6 is used for controlling the opening degree of the first pipeline 4, so that the size of the negative pressure in the first pipeline 4 is controlled, the smaller the opening degree of the jet valve 6 is, the larger the negative pressure generated in the first pipeline 4 is, namely the larger the generated vacuum degree is, the faster the gas in the crankcase 1 enters the supercharger 7, so that the gas in the crankcase 1 can realize a good ventilation effect, and the gas leakage in the crankcase 1 is avoided to cause environmental pollution.

Preferably, the device also comprises a first pipeline 4 and a second pipeline 8, wherein the inlet end of the first pipeline 4 is communicated with the inlet end of the second pipeline 8; the jet valve 6 is arranged on the first pipeline 4, the inlet end of the first pipeline 4 is communicated with the inlet end of the supercharger 7, and the outlet end of the first pipeline 4 is communicated with the outlet end of the supercharger 7;

the inlet end of the second pipeline 8 is communicated with the supercharger 7, the outlet end of the second pipeline 8 is communicated with the intake manifold 2, a throttle valve 9 and an intercooler 10 are arranged on the second pipeline 8, the inlet end of the intercooler 10 is communicated with the supercharger 7, and the outlet end of the intercooler 10 is communicated with the throttle valve 9.

Specifically, the second pipeline 8 is used for re-introducing the gas in the crankcase 1 into the intake manifold 2 for combustion, so as to prevent the gas in the crankcase 1 from polluting the environment.

Preferably, the air purifier further comprises a filtering device, the filtering device comprises an air filter 11, a first oil-gas separator 12, a second oil-gas separator 13 and a third oil-gas separator 14, an inlet end of the air filter 11 is communicated with an outlet end of the supercharger 7, an outlet end of the air filter 11 is communicated with the first oil-gas separator 12, one end of the second oil-gas separator 13 is communicated with the first oil-gas separator 12, and the other end of the second oil-gas separator 13 is communicated with the third oil-gas separator 14.

Preferably, the second gas-oil separator 13 is arranged inside the crankcase 1, the third gas-oil separator 14 is arranged outside the crankcase 1, and gas in the crankcase 1 can enter the jet valve 6 or the crankcase forced ventilation valve 5 through the second gas-oil separator 13.

Specifically, when the third gas-oil separator 14 is in operation, only one of the two outlet ends is communicated with the inlet end, and the other outlet end is in a closed state, that is, when the crankcase forced ventilation valve 5 is communicated with the intake manifold 2, the jet valve 6 is in a closed state, and gas in the crankcase 1 enters the intake manifold 2 through the crankcase forced ventilation valve 5; when the jet valve 6 is in an open state, the crankcase forced ventilation valve 5 is in a closed state, gas in the crankcase 1 passes through the jet valve 6 and enters the first pipeline 4, then passes through the supercharger 7, and finally passes through the second pipeline 8 and enters the intake manifold 2, so that the gas in the crankcase 1 passes through the jet valve 6 and enters the intake manifold 2 to complete ventilation of the crankcase 1.

Preferably, the system further comprises an intake manifold 2 and an air supply pipe 3, wherein one end of the air supply pipe 3 is communicated with the atmosphere, the other end of the air supply pipe 3 is communicated with the supercharger 7, and the intake manifold 2 is communicated with the crankcase forced ventilation valve 5.

Preferably, the third gas-oil separator 14 comprises a third outlet end, a fourth outlet end and a second inlet end, the second inlet end is communicated with the second gas-oil separator 13, the third outlet end is communicated with the intake manifold 2 through a positive crankcase ventilation valve 5, and the fourth outlet end is communicated with the jet valve 6.

Preferably, the jet valve 6 includes a first outlet end, a second outlet end and a first inlet end, the second outlet end is communicated with the crankcase 1, a partition plate is arranged between the first inlet end and the second outlet end, the partition plate is used for opening or closing the jet valve 6, the flow of gas passing through the jet valve 6 can be adjusted, the jet valve is added, and the gas flow of the jet valve is controlled by using a controller, so that the accurate control of the pressure in the crankcase 1 is realized.

Specifically, the controller can control the opening degree of the partition in accordance with the rotation speed of the engine, and the opening degree of the partition is gradually decreased to increase the degree of vacuum generated by the gas passing through the jet valve 6 as the rotation speed of the engine is gradually increased.

The working process of the crankcase ventilation control system is as follows: when the rotating speed of the engine is lower than the first preset value, controlling the crankcase forced ventilation valve 5 to be opened, so that the crankcase 1 and the intake manifold 2 are communicated with each other, and the gas in the crankcase 1 enters the intake manifold 2 to be combusted again, thereby finishing the ventilation in the crankcase 1; when the rotating speed of the engine is greater than the first preset value, the crankcase forced ventilation valve 5 is controlled to be closed, the crankcase 1 and the intake manifold 2 cannot be communicated, the jet valve 6 is controlled to be opened, meanwhile, the supercharger 7 is controlled to start working, after the supercharger 7 boosts the pressure of gas, the jet valve 6 is used for enabling the first pipeline 4 to generate vacuum degree, the gas in the crankcase 1 is sucked into the supercharger 7, the gas enters the intake manifold 2 through the second pipeline 8, therefore, the ventilation in the crankcase 1 is completed, the jet valve 6 is added, the gas flow of the jet valve 6 is controlled through a controller, the accurate control of the pressure of the crankcase 1 is achieved, and the gas in the crankcase 1 can achieve a good ventilation effect.

Specifically, the controller can control the opening degree of the jet valve 6, and when the rotating speed is not greater than a second preset value, the opening degree of the jet valve 6 is controlled to be a first value;

when the rotating speed is between the second preset value and the third preset value, controlling the opening degree of the jet valve 6 to be a second value;

when the rotating speed is not less than the third preset value, controlling the opening degree of the jet valve 6 to be a third value; wherein the second preset value is smaller than the third preset value.

Specifically, the first value is greater than the second value, the second value is greater than the third value, works as when the aperture of fluidic valve 6 is the first value, fluidic valve 6's aperture is the biggest, the rotational speed of engine is big more the aperture of fluidic valve 6 is less, when fluidic valve 6's aperture is the least, gaseous process the vacuum that produces behind fluidic valve 6 is the biggest, through increasing fluidic valve 6 to use the controller to control fluidic valve 6's gas flow, it is right to realize the accurate control of 1 pressure of crankcase, make gaseous homoenergetic in the crankcase 1 realizes good ventilation effect, has avoided destroying crankcase 1's sealed, and then avoids gas leakage polluted environment in the crankcase 1.

In this document, the terms front, back, upper and lower are used to define the components in the drawings and the positions of the components relative to each other, and are used for clarity and convenience of the technical solution. It is to be understood that the use of the directional terms should not be taken to limit the scope of the claims.

While the invention has been described in connection with what is presently considered to be the most practical and preferred embodiment, it is to be understood that the invention is not to be limited to the disclosed embodiment, but on the contrary, is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims.