Ventilation system for an engine crankcase

Abstract

The application relates to a ventilation system for an engine crankcase, comprising a ventilation circulation assembly, a pressurized air source supply assembly and a control assembly; the crankcase is connected in series to the ventilation circulation assembly, and the ventilation circulation assembly is used for ventilation circulation of the crankcase; the ventilation circulation assembly comprises an air filter, a supercharger, an intake manifold, an air outlet end of the crankcase, a mixing cavity and an ice suppression cavity which are sequentially communicated to form a closed loop; the air outlet ends of the pressurized air source supply assembly are respectively communicated with the mixing cavity and the ice suppression cavity; the control assembly is configured to control the on-off of a connecting pipeline between the supercharger and the intake manifold and the opening and closing of the air outlet ends of the pressurized air source supply assembly according to an ambient temperature state; and the control assembly is further configured to control the opening and closing of the air outlet ends of the pressurized air source supply assembly according to a pressure state of the pressurized air source supply assembly. The application can prevent waste gas water vapor of the crankcase from being condensed and frozen when passing through a position where condensation is prone to occur, thereby reducing damage to the supercharger.

Description

Technical Field

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

[0002] When the engine is running, the high-temperature, high-pressure gases in the combustion chamber enter the crankcase along with the piston rings. To prevent damage to the crankcase seal and reduce the impact on engine oil performance, these gases need to be expelled from the crankcase promptly; this is generally referred to as crankcase ventilation. With increasingly stringent emission requirements, crankcase ventilation also needs to be subject to emission limits. The most common application scenario is to pass the crankcase exhaust gases through an oil-gas separator, and then introduce the remaining exhaust gases through a pipeline to the inlet of the turbocharger, where they are re-entered into the cylinder for combustion with fresh air, thus avoiding environmental pollution. However, in extremely cold weather, turbocharger blades are prone to bending, and even the entire turbocharger assembly can be damaged. Summary of the Invention

[0003] Therefore, it is necessary to provide a ventilation system for the engine crankcase to address the issue of how to prevent damage to the turbocharger.

[0004] As one aspect of this application, a ventilation system for an engine crankcase is provided, comprising:

[0005] A ventilation circulation assembly is provided, in which the crankcase is connected in series. The ventilation circulation assembly is used for ventilation circulation of the crankcase. The ventilation circulation assembly includes an air filter, a turbocharger, an intake manifold, an outlet end of the crankcase, a mixing chamber, and an anti-icing chamber, which are connected in sequence to form a closed loop.

[0006] A pressurized air supply assembly, wherein the outlet of the pressurized air supply assembly is connected to both the mixing chamber and the ice-suppressing chamber; and

[0007] A control component is configured to control the connection between the turbocharger and the intake manifold and the opening and closing of the outlet end of the boost air supply component according to the ambient temperature state; the control component is also configured to control the opening and closing of the outlet end of the boost air supply component according to the pressure state of the boost air supply component.

[0008] In one embodiment, the booster gas supply assembly includes:

[0009] An air compressor is configured to pressurize room temperature air;

[0010] The first interface, the first end of the first interface is connected to the air outlet of the air compressor through the connecting pipe;

[0011] The gas storage tank is connected to the second end of the first interface via the connecting pipe; and

[0012] The second interface has a first end connected to the third end of the first interface via the connecting pipe; the second end of the second interface is connected to the mixing chamber via the connecting pipe; and the third end of the second interface is connected to the ice suppression chamber via the connecting pipe.

[0013] In one embodiment, the control component includes:

[0014] The first sensing unit is configured to acquire ambient temperature information;

[0015] An electronic control unit, communicatively connected to the first sensing unit, is configured to receive ambient temperature information sent by the first sensing unit; the electronic control unit is also configured to determine a first comparison result between the ambient temperature information and a preset temperature; and

[0016] A first control valve is installed on the connecting line between the turbocharger and the intake manifold and is communicatively connected to the electronic control unit; the first control valve is configured to receive a first comparison result sent by the electronic control unit and to open or close the first control valve according to the first comparison result.

[0017] In one embodiment, the control component further includes:

[0018] A second sensing unit, communicatively connected to the electronic control unit, is configured to acquire the gas pressure of the gas storage tank. The electronic control unit is further configured to determine a second comparison result between the gas pressure of the gas storage tank and a preset pressure.

[0019] A second control valve is installed on the connection channel between the first interface and the second interface, and the second control valve is communicatively connected to the electronic control unit. The second control valve is configured to open and close according to the second comparison result output by the electronic control unit.

[0020] In one embodiment, the mixing chamber includes:

[0021] The valve stem has its first end connected to the air outlet of the crankcase via the connecting pipe.

[0022] A mixing chamber, wherein a first end of the mixing chamber is connected to a second end of the air nozzle, and the second end of the air nozzle extends into the mixing chamber; the central axis of the air nozzle coincides with the central axis of the mixing chamber, and the mixing chamber is sleeved outside the air nozzle;

[0023] A mixing chamber inlet, the first end of which is connected to the outlet of the pressurized air supply assembly; the second end of which is connected to the mixing chamber body; and

[0024] The mixing chamber has an air outlet, the first end of which is connected to the air inlet of the ice suppression chamber via a connecting pipe; the second end of the mixing chamber has an air outlet connected to the second end of the mixing chamber.

[0025] In one embodiment, the ratio of the inner diameter of the mixing chamber inlet to the inner diameter of the nozzle is 1.5 to 2; wherein, the second end of the mixing chamber inlet is connected to the mixing chamber along the tangential direction of the mixing chamber.

[0026] In one embodiment, the ice-suppressing cavity includes:

[0027] An ice-suppressing chamber, the first end of which is connected to the air outlet of the air filter through the connecting pipe; the second end of which is connected to the air inlet of the booster through the connecting pipe.

[0028] The first air inlet of the first ice-suppressing cavity is connected at its first end to the air outlet of the pressurized air supply component; the second end of the first air inlet of the first ice-suppressing cavity is connected to the ice-suppressing cavity body.

[0029] The second ice-suppressing chamber air inlet, the first end of which is connected to the air outlet of the mixing chamber via the connecting pipe; the second end of which is connected to the ice-suppressing chamber body; and

[0030] An extension pipe is provided, wherein the first end of the extension pipe is connected to the second end of the air inlet of the first ice-suppressing cavity, and the extension pipe is connected to the inner wall of the ice-suppressing cavity; the second end of the extension pipe is opposite to the second end of the air inlet of the second ice-suppressing cavity.

[0031] In one embodiment, the central axis of the first ice-suppressing cavity air inlet and the central axis of the second ice-suppressing cavity air inlet are perpendicular to the central axis of the ice-suppressing cavity; wherein, the ratio of the cross-sectional area of ​​the second end of the extension pipe to the cross-sectional area of ​​the second end of the second ice-suppressing cavity air inlet is 1 to 1.5.

[0032] In one embodiment, the control component is configured to control the connection between the turbocharger and the intake manifold based on ambient temperature conditions, including:

[0033] When the ambient temperature is higher than a preset temperature, the connection between the turbocharger and the intake manifold is opened, and the outlet of the boost air supply assembly is closed; wherein, the preset temperature is configured as the freezing point temperature; and

[0034] When the ambient temperature is lower than the preset temperature, the connecting pipe between the turbocharger and the intake manifold is closed, and the outlet end of the boost air supply component is opened.

[0035] In one embodiment, the control component is further configured to control the opening and closing of the outlet end of the booster gas supply component according to the pressure state of the booster gas supply component, including:

[0036] When the pressure at the gas source end of the booster gas supply component exceeds the maximum value of a preset pressure threshold, the gas outlet end of the booster gas supply component opens; and

[0037] When the pressure at the gas source end of the booster gas supply component is less than the minimum value of the preset pressure threshold, the gas outlet end of the booster gas supply component is closed.

[0038] This application utilizes the boosted air supply component to supply a boosted airflow that, under the control of the control component, purges the mixing chamber and the anti-icing chamber separately. This prevents the exhaust gas water vapor in the crankcase from condensing and freezing at locations prone to condensation, such as crankcase piping and gas interfaces, thereby reducing damage to the booster. Attached Figure Description

[0039] Figure 1 A schematic diagram of a ventilation system for an engine crankcase according to an embodiment of this application is shown.

[0040] Figure 2 A three-dimensional structural diagram of a mixing chamber in a ventilation system for an engine crankcase, provided in an embodiment of this application, is shown.

[0041] Figure 3a and Figure 3b The diagram shows cross-sectional views AA and BB of a mixing chamber in a ventilation system for an engine crankcase according to an embodiment of this application.

[0042] Figure 4 A perspective view of the anti-icing cavity structure in a ventilation system for an engine crankcase according to an embodiment of this application is shown.

[0043] Figure 5 It shows Figure 4 A top-down view.

[0044] Figure 6 It shows Figure 5 Cross-sectional view of the middle CC section.

[0045] Figure 7 It shows Figure 6 A magnified view of a portion of K.

[0046] Icon labels:

[0047] 10-Crankcase;

[0048] 20 - Mixing chamber;

[0049] 21-Valve;

[0050] 22-Mixing cavity;

[0051] 23 - Mixing chamber air inlet;

[0052] 24 - Mixing chamber outlet;

[0053] 30-Ice-suppressing cavity;

[0054] 31-Ice-suppressing cavity;

[0055] 32 - First ice-suppressing chamber air inlet;

[0056] 33 - Second ice-suppressing chamber air inlet;

[0057] 34 - Extension piping;

[0058] 40 - Turbocharger;

[0059] 50 - Intake manifold;

[0060] 61 - Air compressor;

[0061] 62-First Interface;

[0062] 63 - Gas storage tank;

[0063] 64 - Second Interface;

[0064] 71 - First sensing unit;

[0065] 72-Electronic Control Unit;

[0066] 73 - First control valve;

[0067] 74 - Second sensing unit;

[0068] 75 - Second control valve;

[0069] 76 - Safety valve;

[0070] 80-Air filter;

[0071] 90-exhaler. Detailed Implementation

[0072] To make the above-mentioned objectives, features, and advantages of this application more apparent and understandable, the specific embodiments of this application are described in detail below with reference to the accompanying drawings. Many specific details are set forth in the following description to provide a thorough understanding of this application. However, this application can be implemented in many other ways different from those described herein, and those skilled in the art can make similar modifications without departing from the spirit of this application. Therefore, this application is not limited to the specific embodiments disclosed below.

[0073] In the description of this application, it should be understood that if terms such as "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential" appear, these terms indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application.

[0074] Furthermore, where the terms "first" and "second" appear, these terms are for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined with "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this application, where the term "multiple" appears, "multiple" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0075] In this application, unless otherwise expressly specified and limited, the terms "installation," "connection," "joining," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise expressly limited. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.

[0076] In this application, unless otherwise expressly specified and limited, the use of descriptions such as "above" or "below" the second feature indicates that the first and second features are in direct contact or indirect contact via an intermediate medium. Furthermore, "above," "on top of," and "over" the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. Similarly, "below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0077] It should be noted that if an element is referred to as being "fixed to" or "set on" another element, it can be directly on the other element or there may be an intervening element. If an element is considered to be "connected to" another element, it can be directly connected to the other element or there may be an intervening element. If so, the terms "vertical," "horizontal," "upper," "lower," "left," "right," and similar expressions used in this application are for illustrative purposes only and do not represent the only possible implementation.

[0078] The main reason for turbocharger damage in extremely cold weather is the high moisture content in the crankcase exhaust gas. When the engine stops, this moisture condenses and gradually accumulates into ice in the low-flow-rate areas of the piping, adhering to the pipe walls. When the engine starts, the temperature of the crankcase ventilation exhaust gas gradually rises, causing some of the ice to melt. Under the influence of airflow and pressure difference, the ice is carried into the turbocharger's pressure end. The high-speed impeller can be bent or even damaged by the impact of the ice, thus affecting engine power. In addition, at the inlet of the turbocharger's pressure end, the low-temperature fresh air meets the high-temperature crankcase exhaust gas, and ice formation is very likely to occur at the interface between the crankcase ventilation exhaust gas and fresh air. Small ice crystals falling off at this point can also cause serious damage to the turbocharger's pressure end blades.

[0079] See Figure 1 As shown, Figure 1 A schematic diagram of a ventilation system for an engine crankcase according to an embodiment of this application is shown.

[0080] One embodiment of this application provides a ventilation system for an engine crankcase, comprising: a ventilation circulation assembly, a booster air supply assembly, and a control assembly; a crankcase 10 is connected in series in the ventilation circulation assembly, which is used for ventilation circulation of the crankcase 10; the ventilation circulation assembly includes an air filter 80, a booster 40, an intake manifold 50, an outlet of the crankcase 10, a mixing chamber 20, and an anti-icing chamber 30, the above components being sequentially connected to form a closed loop; the outlet of the booster air supply assembly is connected to the mixing chamber 20 and the anti-icing chamber 30 respectively; the control assembly is configured to control the connection between the booster 40 and the intake manifold 50 and the opening and closing of the outlet of the booster air supply assembly according to the ambient temperature state; the control assembly is also configured to control the opening and closing of the outlet of the booster air supply assembly according to the pressure state of the booster air supply assembly.

[0081] In one embodiment of this application, the pressurized air supply component includes: an air compressor 61, a first interface 62, an air storage tank 63, and a second interface 64. The air compressor 61 is configured to pressurize room temperature air; the first end of the first interface 62 is connected to the outlet end of the air compressor 61 via a connecting pipe; the air storage tank 63 is connected to the second end of the first interface 62 via a connecting pipe; the first end of the second interface 64 is connected to the third end of the first interface 62 via a connecting pipe; the second end of the second interface 64 is connected to the mixing chamber 20 via a connecting pipe; and the third end of the second interface 64 is connected to the ice suppression chamber 30 via a connecting pipe.

[0082] The control components include: a first sensing unit 71, an electronic control unit 72, and a first control valve 73. The first sensing unit 71 is configured to acquire ambient temperature information; the electronic control unit 72 is communicatively connected to the first sensing unit 71 and is configured to receive the ambient temperature information sent by the first sensing unit 71; the electronic control unit 72 is also configured to determine a first comparison result between the ambient temperature information and a preset temperature; the first control valve 73 is installed on the connecting pipe between the turbocharger 40 and the intake manifold 50 and is communicatively connected to the electronic control unit 72; the first control valve 73 is configured to receive the first comparison result sent by the electronic control unit 72 and execute the opening and closing of the first control valve 73 according to the first comparison result.

[0083] Furthermore, the control assembly also includes a second sensing unit 74 and a second control valve 75. The second sensing unit 74 is communicatively connected to the electronic control unit 72 and is configured to acquire the gas pressure of the gas storage tank 63. The electronic control unit 72 is also configured to determine a second comparison result between the gas pressure of the gas storage tank 63 and a preset pressure. The second control valve 75 is installed on the connection channel between the first interface 62 and the second interface 64, and is communicatively connected to the electronic control unit 72. The second control valve 75 is configured to open and close according to the second comparison result output by the electronic control unit 72. Generally, the safety valve 76 is located at the top of the gas storage tank 63. The gas storage tank 63 has a permissible safety pressure. When the gas pressure exceeds the permissible safety pressure, the excess gas in the gas storage tank 63 can be discharged to the atmosphere through the safety valve 76.

[0084] The control component mentioned above is configured to control the connection between the turbocharger 40 and the intake manifold 50 according to the ambient temperature. The details are as follows: when the ambient temperature is higher than the preset temperature, the connection between the turbocharger 40 and the intake manifold 50 is open, and the outlet of the boost air supply component is closed. The preset temperature is set to the freezing point. When the ambient temperature is lower than the preset temperature, the connection between the turbocharger 40 and the intake manifold 50 is closed, and the outlet of the boost air supply component is open.

[0085] The control component mentioned above is further configured to control the opening and closing of the outlet end of the booster air supply component according to the pressure state of the booster air supply component. The details are as follows: when the pressure at the air source end of the booster air supply component is greater than the maximum value of the preset pressure threshold, the outlet end of the booster air supply component is opened; when the pressure at the air source end of the booster air supply component is less than the minimum value of the preset pressure threshold, the outlet end of the booster air supply component is closed.

[0086] See Figure 2 , Figure 3a and Figure 3b As shown, Figure 2 This invention provides a schematic diagram of the three-dimensional structure of a mixing chamber in a ventilation system for an engine crankcase according to an embodiment of this application. Figure 3a and Figure 3bThis illustration shows cross-sectional views AA and BB of a mixing chamber in a ventilation system for an engine crankcase according to an embodiment of this application. The specific structure of the mixing chamber 20 is described in detail below. The mixing chamber 20 includes: a nozzle 21, a mixing chamber body 22, a mixing chamber inlet 23, and a mixing chamber outlet 24. The first end of the nozzle 21 is connected to the outlet end of the crankcase 10 via a connecting pipe; the first end of the mixing chamber body 22 is connected to the second end of the nozzle 21, and the second end of the nozzle 21 extends into the mixing chamber body 22; the central axis of the nozzle 21 coincides with the central axis of the mixing chamber body 22, and the mixing chamber body 22 is fitted outside the nozzle 21; the first end of the mixing chamber inlet 23 is connected to the outlet end of a booster air supply assembly; the second end of the mixing chamber inlet 23 is connected to the mixing chamber body 22; the first end of the mixing chamber outlet 24 is connected to the inlet end of an ice suppression chamber 30 via a connecting pipe; the second end of the mixing chamber outlet 24 is connected to the second end of the mixing chamber 22.

[0087] Compressed air is supplied by the booster air source assembly and introduced into the mixing chamber 20 through the mixing chamber inlet 23. Exhaust gas from the crankcase is introduced through the nozzle 21. The compressed air and crankcase exhaust gas mix within the mixing chamber 22 and are then discharged through the mixing chamber outlet 24, subsequently entering the ice-suppressing chamber. In this embodiment, the mixing chamber 20 is a baseball bat structure, and the entire structure can be made of plastic. Generally, the nozzle 21 and the mixing chamber inlet 23 are located at the larger end of the mixing chamber, while the mixing chamber outlet 24 is located at the smaller end. The transition from the mixing chamber inlet 23 to the mixing chamber outlet 24 is achieved through a tapered structure.

[0088] In one optional embodiment, the mixing chamber inlet 23 has a two-layer concentric cylindrical structure on one side. Compressed air is in the outer flow channel of the two-layer concentric cylindrical structure, and the crankcase exhaust gas is in the inner flow channel of the two-layer concentric cylindrical structure. It should be noted that the nozzle 21 is a hollow tube structure, and the inner diameter of the nozzle 21 is the same as the inner diameter of the interface.

[0089] The ratio of the inner diameter of the mixing chamber inlet 23 to the inner diameter of the nozzle 21 is 1.5 to 2. By utilizing the difference between the inner diameter of the mixing chamber inlet 23 and the inner diameter of the nozzle 21, a negative pressure is generated inside the mixing chamber, which is more conducive to the mixing effect of the gas in the mixing chamber.

[0090] In an optional embodiment, the second end of the mixing chamber inlet 23 is connected to the mixing chamber 22 along the tangential direction of the mixing chamber 22, which is more conducive to the mixing effect of the gas in the mixing chamber.

[0091] See Figures 4 to 7 As shown, Figure 4 This illustration shows a perspective view of an anti-icing cavity structure in a ventilation system for an engine crankcase according to an embodiment of this application. Figure 5 It shows Figure 4A top-down view diagram. Figure 6 It shows Figure 5 CC section view, Figure 7 It shows Figure 6 A magnified view of a portion of the K-shaped section. A detailed explanation of the specific structure of the ice-suppressing cavity 30 is provided.

[0092] The ice suppression chamber 30 includes: an ice suppression chamber body 31, a first ice suppression chamber air inlet 32, a second ice suppression chamber air inlet 33, and an extension pipe 34. The first end of the ice-suppressing chamber 31 (i.e., the air inlet of the ice-suppressing chamber) is connected to the air outlet of the air filter 80 through a connecting pipe; the second end of the ice-suppressing chamber 31 (i.e., the air outlet of the ice-suppressing chamber) is connected to the air inlet of the booster 40 through a connecting pipe; the first end of the first ice-suppressing chamber air inlet 32 ​​is connected to the air outlet of the booster air supply component; the second end of the first ice-suppressing chamber air inlet 32 ​​is connected to the ice-suppressing chamber 31; the first end of the second ice-suppressing chamber air inlet 33 is connected to the air outlet of the mixing chamber 20 through a connecting pipe; the second end of the second ice-suppressing chamber air inlet 33 is connected to the ice-suppressing chamber 31; the first end of the extension pipe 34 is connected to the second end of the first ice-suppressing chamber air inlet 32, and the extension pipe 34 is connected to the inner wall of the ice-suppressing chamber 31; the second end of the extension pipe 34 is opposite to the second end of the second ice-suppressing chamber air inlet 33.

[0093] The ice suppression chamber 30 is equipped with three air inlets: the first end of the ice suppression chamber body 31, the first ice suppression chamber air inlet 32, and the second ice suppression chamber air inlet 33. The first end of the ice suppression chamber body 31 is connected to the air filter 80. Compressed air supplied by the booster air source assembly enters the first ice suppression chamber air inlet 32. The second ice suppression chamber air inlet 33 is connected to the mixing chamber outlet 24. The ice suppression chamber 30 has one outlet at the second end of the ice suppression chamber body 31, which is connected to the booster pressure end. The extension pipe 34 intersects with the first ice suppression chamber air inlet 32 ​​at the pipe outlet within the ice suppression chamber and is arranged at a right angle.

[0094] Specifically, the central axis of the first ice-suppressing cavity air inlet 32 ​​and the central axis of the second ice-suppressing cavity air inlet 33 are perpendicular to the central axis of the ice-suppressing cavity body 31.

[0095] In an optional embodiment, the ratio of the cross-sectional area of ​​the second end of the extension pipe 34 to the cross-sectional area of ​​the second end of the second ice-suppressing cavity inlet 33 is 1 to 1.5.

[0096] In one embodiment, when the engine is started, the air compressor 61 is driven to start working through gear transmission. The air compressor 61 draws in air from the environment and discharges high-pressure gas from the air outlet of the air compressor 61.

[0097] The electronic control unit 72 detects the ambient temperature and the pressure of the air tank 63 through the first sensing unit 71 (temperature sensing) and the second sensing unit 74 (pressure sensing), respectively. When the ambient temperature is higher than the freezing point, it is determined that there is no risk of icing in the pipeline. The second control valve is activated, and the first interface 62 and the second interface 64 are not connected. At this time, the gas pumped by the air compressor 61 is completely introduced into the air tank 63 through the first interface 62. The exhaust gas from the engine to the crankcase passes through the breather 90 and then passes through the mixing chamber 20, the anti-icing chamber 30, and enters the intake end of the turbocharger 40 together with the fresh air output from the air filter 80.

[0098] When the ambient temperature is below the freezing point, it is determined that there is a risk of icing in the pipeline. The second sensing unit monitors in real time whether the pressure of the air tank is higher than the maximum value of the preset pressure threshold (e.g., 800 kPa). If the pressure of the air tank is lower than the maximum value of the preset pressure threshold, the second control valve does not operate, and the air pumped by the air compressor prioritizes meeting the pressure build-up requirements of the air tank.

[0099] If the pressure in the air tank is higher than the maximum value of the preset pressure threshold, the pressure pumped out by the air compressor has met the pressure building requirements of the air tank. At this time, the second control valve 75 opens and closes intermittently, allowing the excess high-pressure air pumped out by the air compressor to be introduced into the second interface 64, which is then divided into two paths that are introduced into the mixing chamber and the ice suppression chamber respectively.

[0100] A portion of the high-pressure air enters the mixing chamber 20 and flows tangentially along the wall. The rough surface of the mixing chamber 20 helps to partially heat and insulate the high-pressure air. Meanwhile, the exhaust gas from the crankcase flowing in from the nozzle 21 mixes with the high-speed high-pressure air within the mixing chamber 20. This mixture moves tangentially along the inner wall of the mixing chamber 22, ensuring thorough mixing. Even if water vapor condenses into small droplets and eventually ice, the high-speed airflow and rough wall prevent the formation of large ice blocks. The mixture then enters the ice-suppressing chamber 30 through the mixing chamber outlet 24 and the second ice-suppressing chamber inlet 33. Another portion of the high-pressure air enters the ice-suppressing chamber 30 through the first ice-suppressing chamber inlet 32 ​​and then along the extension pipe 34. After mixing with the mixture from the second ice-suppressing chamber inlet 33 in the middle section of the extension pipe 34, it is then mixed with fresh air from the air filter 80. Because the extension pipe 34 and the second ice-suppressing chamber air inlet 33 intersect, some of the high-pressure air will purge the interface between the extension pipe 34 and the second ice-suppressing chamber air inlet 33. The high-speed purging will also suppress the icing phenomenon at the interface.

[0101] When engine 1 is detected to have stopped, the electronic control unit 72 continues to control the second control valve 75 to open and close intermittently until the pressure in the gas tank 63 drops below a preset pressure threshold (e.g., 600 kPa). At this point, some of the high-pressure gas in the gas tank 63 can be discharged into the ventilation system for the engine crankcase. Through the exhaust action after engine shutdown, the residual condensate in the ventilation system pipes for the engine crankcase can be blown to the inlet of the turbocharger 40. Since the residual condensate in the pipes is relatively small but has a small inner wall surface area, it is easy for this residual condensate to freeze into large ice blocks in extremely cold weather. Therefore, high-pressure gas is used to blow this portion of condensate to the inlet of the turbocharger 40. At the same time, the temperature of the turbocharger 40 casing can be used to evaporate some of the condensate, further dispersing the condensate and ensuring that even if ice forms, it will be small ice crystals, thereby reducing the risk of turbocharger blade damage.

[0102] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0103] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the patent application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this patent application should be determined by the appended claims.

Claims

1. A ventilation system for an engine crankcase, characterized in that, include: A ventilation circulation assembly is connected in series with the crankcase (10) in the ventilation circulation assembly, which is used for ventilation circulation of the crankcase (10); the ventilation circulation assembly includes an air filter (80), a turbocharger (40), an intake manifold (50), an air outlet of the crankcase (10), a mixing chamber (20), and an ice suppression chamber (30) that are connected in sequence to form a closed loop. A pressurized air supply assembly, wherein the air outlet of the pressurized air supply assembly is connected to the mixing chamber (20) and the ice suppression chamber (30) respectively; as well as A control component is configured to control the opening and closing of the first connecting pipeline between the turbocharger (40) and the intake manifold (50) and the outlet end of the boost air supply component according to the ambient temperature state; the control component is also configured to control the opening and closing of the outlet end of the boost air supply component according to the pressure state of the boost air supply component. The control component is configured to control the opening and closing of the first connecting pipe between the turbocharger (40) and the intake manifold (50) and the outlet end of the boost air supply component according to the ambient temperature. When the ambient temperature is higher than a preset temperature, the first connecting pipe between the turbocharger (40) and the intake manifold (50) is opened, and the outlet end of the boost air supply component is closed. The preset temperature is configured to be the freezing point temperature. When the ambient temperature is lower than the preset temperature, the turbocharger (40)... The first connecting pipe between the intake manifold (50) and the intake manifold (0) is closed, and the outlet end of the boost air supply component is opened; the control component is further configured to control the opening and closing of the outlet end of the boost air supply component according to the pressure state of the boost air supply component. When the pressure at the air source end of the boost air supply component is greater than the maximum value of the preset pressure threshold, the outlet end of the boost air supply component is opened; when the pressure at the air source end of the boost air supply component is less than the minimum value of the preset pressure threshold, the outlet end of the boost air supply component is closed.

2. The ventilation system for an engine crankcase according to claim 1, characterized in that, The booster air supply component includes: An air compressor (61) is configured to pressurize room temperature air; The first interface (62) is connected to the air outlet of the air compressor (61) through a second connecting pipe. The gas storage tank (63) is connected to the second end of the first interface (62) via a third connecting pipe; and The second interface (64) has a first end connected to the third end of the first interface (62) via a fourth connecting pipe; the second end of the second interface (64) is connected to the mixing chamber (20) via a fifth connecting pipe; and the third end of the second interface (64) is connected to the ice suppression chamber (30) via a sixth connecting pipe.

3. The ventilation system for an engine crankcase according to claim 2, characterized in that, The control component includes: The first sensing unit (71) is configured to acquire ambient temperature information; An electronic control unit (72) is communicatively connected to the first sensing unit (71). The electronic control unit (72) is configured to receive the ambient temperature information sent by the first sensing unit (71). The electronic control unit (72) is also configured to determine a first comparison result between the ambient temperature information and a preset temperature. The first control valve (73) is installed on the seventh connecting line between the turbocharger (40) and the intake manifold (50) and is communicatively connected to the electronic control unit (72); the first control valve (73) is configured to receive the first comparison result sent by the electronic control unit (72) and to open and close the first control valve (73) according to the first comparison result.

4. The ventilation system for an engine crankcase according to claim 3, characterized in that, The control component also includes: A second sensing unit (74) is communicatively connected to the electronic control unit (72). The second sensing unit (74) is configured to acquire the gas pressure of the gas storage tank (63). The electronic control unit (72) is further configured to determine a second comparison result between the gas pressure of the gas storage tank (63) and a preset pressure. The second control valve (75) is installed on the connection channel between the first interface (62) and the second interface (64), and the second control valve (75) is communicatively connected to the electronic control unit (72). The second control valve (75) is configured to open and close the second control valve (75) according to the second comparison result output by the electronic control unit (72).

5. The ventilation system for an engine crankcase according to claim 1, characterized in that, The mixing chamber (20) includes: The first end of the air nozzle (21) is connected to the air outlet of the crankcase (10) through an eighth connecting pipe. A mixing chamber (22) has a first end connected to the second end of the air nozzle (21), and the second end of the air nozzle (21) extends into the mixing chamber (22); the central axis of the air nozzle (21) coincides with the central axis of the mixing chamber (22), and the mixing chamber (22) is sleeved outside the air nozzle (21); A mixing chamber inlet (23), the first end of which is connected to the outlet of the pressurized air supply assembly; the second end of which is connected to the mixing chamber body (22); and The mixing chamber outlet (24) has its first end connected to the air inlet of the ice suppression chamber (30) via a connecting pipe; the second end of the mixing chamber outlet (24) is connected to the second end of the mixing chamber body (22).

6. The ventilation system for an engine crankcase according to claim 5, characterized in that, The ratio of the inner diameter of the mixing chamber inlet (23) to the inner diameter of the nozzle (21) is 1.5 to 2; wherein, the second end of the mixing chamber inlet (23) is connected to the mixing chamber (22) along the tangential direction of the mixing chamber (22).

7. The ventilation system for an engine crankcase according to claim 1, characterized in that, The ice suppression cavity (30) includes: An ice-suppressing chamber (31) is provided, with its first end connected to the air outlet of the air filter (80) via a connecting pipe; and its second end connected to the air inlet of the booster (40) via a tenth connecting pipe. The first end of the first ice-suppressing cavity air inlet (32) is connected to the air outlet of the pressurized air supply component; the second end of the first ice-suppressing cavity air inlet (32) is connected to the ice-suppressing cavity body (31). The second ice-suppressing chamber air inlet (33) has its first end connected to the air outlet of the mixing chamber (20) via an eleventh connecting pipe; the second end of the second ice-suppressing chamber air inlet (33) is connected to the ice-suppressing chamber body (31); and The extension pipe (34) has a first end connected to the second end of the first ice suppression cavity air inlet (32) and the extension pipe (34) is connected to the inner wall of the ice suppression cavity (31); the second end of the extension pipe (34) is opposite to the second end of the second ice suppression cavity air inlet (33).

8. The ventilation system for an engine crankcase according to claim 7, characterized in that, The central axis of the first ice-suppressing cavity air inlet (32) and the central axis of the second ice-suppressing cavity air inlet (33) are perpendicular to the central axis of the ice-suppressing cavity (31).

9. The ventilation system for an engine crankcase according to claim 8, characterized in that, The ratio of the cross-sectional area of ​​the second end of the extension pipe (34) to the cross-sectional area of ​​the second end of the second ice suppression cavity air inlet (33) is 1 to 1.

5.

10. The ventilation system for an engine crankcase according to claim 2, characterized in that, The air pump (61) is driven to start working by gear transmission. The air pump (61) draws in air from the environment and discharges high-pressure gas from the outlet of the air pump (61).

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