Anti-icing engine crankcase ventilation system and method

Abstract

The invention discloses an anti-icing engine crankcase ventilation system which is installed on an engine and comprises an oil-gas separator, a blow-by channel, an air inlet pipe and an air outlet pipe, the engine comprises an air cylinder body, a cylinder cover, an exhaust pipe and a supercharger, the cylinder cover is installed above the air cylinder body, and the exhaust pipe is installed above the air cylinder body. The exhaust pipe is installed on the cylinder cover, and the supercharger is further installed in the middle of the exhaust pipe. At least one longitudinally-arranged blow-by channel is further arranged on the crankcase exhaust side of the air cylinder body. The upper end of the blow-by channel is sealed, and a gas taking opening is formed in the side surface of the upper part; the oil-gas separator is installed on the exhaust side of the air cylinder body, one end of an air inlet pipe of the oil-gas separator is connected with the blow-by channel, oil gas in the crankcase is led into the oil-gas separator, and an air outlet pipe is connected with the air inlet end of the supercharger. The working temperature of the gas outlet pipe of the oil-gas separator ranges from 30 DEG C to 70 DEG C under the high and cold environment, and the risk that a pipeline of a crankcase ventilation system is frozen and blocked is avoided.

Description

Technical Field

[0001] The present invention relates to the technical field of crankcase ventilation systems, and in particular to an engine crankcase ventilation system and method for preventing icing. Background Art

[0002] During engine operation, due to the gap between the piston ring and the cylinder wall, some gas will inevitably flow from the combustion chamber into the engine's crankcase. If this gas is not discharged, the gas pressure in the engine will gradually increase, causing the oil seal to be damaged, and then causing crankcase gas leakage and polluting the environment.

[0003] Existing engine crankcase ventilation systems typically feature crankcase blowby gas channels in the cylinder block and cylinder head. Crankcase gas flows through these channels into the cylinder head shield, where an oil-gas separator is located. This separates the oil from this gas and directs the remaining gas through a breather hose located outside the cylinder head into the intake manifold, allowing it to flow into the cylinders and be burned. The oil-gas separator located inside the cylinder head shield acts as a pre-separator, removing approximately 50% of the oil from the gas. The remaining gas is then separated by the oil-gas separator located outside the cylinder head, which removes 99% of the oil. However, the long pipe connecting the oil-gas separator increases the risk of condensed water freezing.

[0004] Patent document CN107524494A discloses an engine crankcase ventilation system. This system, through an outlet channel provided on the cylinder head, directs the gas separated by the oil-gas separator into the intake duct, ultimately allowing the gas to enter the cylinder of the engine block. This effectively eliminates the existing breather ventilation hose and solves the problem of gas in the breather ventilation hose being easily blocked by freezing when exposed to cold. However, this existing patent still uses a cylinder head pre-separation solution, which is costly and more complex in terms of anti-icing and oil-gas separation than the solution of the present invention.

[0005] For example, the existing patent document CN111997710A discloses an engine crankcase ventilation system and method, in which an EGR exhaust gas mixing valve is arranged before the intersection of the supercharger intake pipe and the breathing pipe. The mixing valve is used to adjust the ratio of EGR exhaust gas to fresh air to achieve heating of the fresh air, thereby increasing the intake air temperature at the end of the breathing pipe. If the intake air temperature exceeds 0°C, the condensed water will not freeze, avoiding the risk of water vapor in the breathing pipe condensing and freezing. This structure is also relatively complex.

[0006] The disclosure of the above background technology content is only used to assist in understanding the concept and technical solution of the present invention. It does not necessarily belong to the prior art of this patent application. In the absence of clear evidence that the above content has been disclosed on the filing date of this patent application, the above background technology should not be used to evaluate the novelty and creativity of this application. Summary of the Invention

[0007] The (main) purpose of the present invention is to propose an engine crankcase ventilation system and method that arranges the crankcase ventilation system on the exhaust side of the cylinder block, and uses the exhaust pipe and supercharger as heat sources to radiate the crankcase ventilation system's blowby channel, oil-gas separator, oil-gas connecting pipe, oil-gas separator inlet pipe and oil-gas separator outlet pipe, so that in a high-cold environment, the operating temperature of the oil-gas separator outlet pipe is between 30-70°C, thereby avoiding ice and blockage of the crankcase ventilation system's pipes.

[0008] To this end, the present invention provides an engine crankcase ventilation system and method for preventing icing.

[0009] Preferably, the present invention may also have the following technical features:

[0010] A crankcase ventilation system for preventing icing, wherein the crankcase ventilation system is installed on the engine and includes an oil-gas separator, a blowby gas passage, an air inlet pipe and an air outlet pipe. The engine includes a cylinder block, a cylinder head, an exhaust pipe and a supercharger. The cylinder head is installed above the cylinder block, and the exhaust pipe is installed on the cylinder head, and the supercharger is also installed in the middle of the cylinder head; at least one longitudinally arranged blowby gas passage is also provided on the exhaust side of the crankcase of the cylinder block; the upper end of the blowby gas passage is sealed, and an air intake is provided on the side of its upper part; the oil-gas separator is installed on the exhaust side of the cylinder block, and one end of the intake pipe is connected to the blowby gas passage to introduce the oil and gas in the crankcase into the oil-gas separator, and the outlet pipe is connected to the intake end of the supercharger.

[0011] Furthermore, the highest point of the air intake port is located below the sealing portion of the upper end of the blowby gas channel.

[0012] Furthermore, the cross-sectional area of ​​the air intake port is smaller than the horizontal cross-sectional area of ​​the blowby gas channel.

[0013] Furthermore, the supercharger is a mid-mounted supercharger.

[0014] Furthermore, the oil-gas separator outlet pipe is a bent pipe structure, and the outlet pipe includes a horizontal pipe and a vertical pipe. One end of the horizontal pipe is connected to the oil-gas separator outlet, and the other end is connected to the lower end of the vertical pipe. The upper end of the vertical pipe is connected to the air inlet end of the supercharger.

[0015] Furthermore, the horizontal pipe is located directly below the supercharger and extends along the length direction of the supercharger.

[0016] Furthermore, it also includes an oil and gas connecting pipe, and the blowby gas channel is set on the exhaust side of the cylinder body; the middle part of the oil and gas connecting pipe is connected to the oil and gas separator inlet pipe, and the two ends are respectively connected to the air intakes of the two blowby gas channels.

[0017] Furthermore, the oil and gas connecting pipe is an N-shaped pipe, which includes a straight pipe and connecting air pipes connected to both ends of the straight pipe, and the straight pipe and the connecting air pipes at both ends have a smooth transition.

[0018] Furthermore, the connecting air pipe and the blowby gas channel form an angle of 20-60 degrees.

[0019] A method for preventing icing of an engine crankcase ventilation system includes the above-mentioned crankcase ventilation system and further includes the following steps: installing the crankcase ventilation system on the exhaust side of the cylinder block and below the exhaust pipe and the supercharger; radiating the high temperature generated by the exhaust pipe and the supercharger during operation to the inlet pipe and the outlet pipe of the oil-gas separator.

[0020] The beneficial effects of the present invention compared with the prior art include: installing the crankcase ventilation system on the exhaust side of the cylinder block, specifically installing the blowby gas channel, oil-gas separator, oil-gas connecting pipe, oil-gas separator inlet pipe and oil-gas separator outlet pipe below the exhaust pipe and the supercharger, and radiating the high temperature generated by the exhaust pipe and the supercharger when they are working to the parts and pipes of the crankcase ventilation system, so that in a high-cold environment, the operating temperature of the oil-gas separator outlet pipe is between 30-70°C, avoiding the risk of freezing and blockage of the crankcase ventilation system pipes. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is a schematic diagram of the application of the present invention on an engine.

[0022] Figure 2 It is a schematic diagram of the main structure of the present invention.

[0023] Figure 3 It is a partial cross-sectional view of the present invention.

[0024] Figure 4 This is a first-perspective view of the oil and gas connecting pipe of the present invention.

[0025] Figure 5 This is a second viewing angle diagram of the oil and gas connecting pipe of the present invention. DETAILED DESCRIPTION

[0026] The present invention will be further described in detail below in conjunction with specific embodiments and with reference to the accompanying drawings. It should be emphasized that the following description is merely illustrative and is not intended to limit the scope of the present invention and its application.

[0027] Non-limiting and non-exclusive embodiments will be described with reference to the following figures, wherein like reference numerals refer to like parts unless otherwise specified.

[0028] like Figures 1 to 5 The engine crankcase ventilation system shown in the figure prevents icing. The crankcase ventilation system is installed on the engine and includes an oil-gas separator 1, a blowby gas passage 41, an intake pipe 11, and an outlet pipe 13. The engine comprises a cylinder block 4, a cylinder head, an exhaust pipe 2, and a supercharger 3. The cylinder block 4 is mounted above the cylinder block 4, and the exhaust pipe 2 is mounted on the cylinder head. The supercharger 3 is also mounted in the center; the supercharger 3 is a centrally mounted supercharger. The crankcase exhaust side of the cylinder block 4 is also provided with at least one longitudinally arranged blowby gas passage 41. The upper end of the blowby gas passage 41 is sealed, and an air intake 42 is provided on the side of the upper portion. The cross-sectional area of ​​the air intake 42 is smaller than the horizontal cross-sectional area of ​​the blowby gas passage 41. The oil-gas separator 1 is installed on the exhaust side of the cylinder block 4. One end of the intake pipe 11 is connected to the blowby gas passage 41, directing oil and gas from the crankcase into the oil-gas separator 1. The outlet pipe 13 is connected to the intake end of the supercharger 3. Preferably, the highest point of the air intake port 42 is located below the sealing portion of the upper end of the blowby gas channel 41 .

[0029] In a preferred embodiment, the outlet pipe 13 of the oil-gas separator 1 is a bent pipe structure. Preferably, the outlet pipe 13 includes a horizontal pipe 131 and a vertical pipe 132. One end of the horizontal pipe 131 is connected to the outlet of the oil-gas separator 1, and the other end is connected to the lower end of the vertical pipe 132. The upper end of the vertical pipe 132 is connected to the air inlet end of the supercharger 3. During operation, the oil and gas enter the air inlet end of the supercharger 3 through the outlet pipe 13 and participate in the engine combustion. Preferably, the horizontal pipe 131 is located directly below the supercharger 3 and extends along the length direction of the supercharger 3. When the supercharger 3 is working, a high-temperature heat source is generated to radiate the outlet pipe 13 of the oil-gas separator 1. The outlet pipe 13 is always radiated by the high-temperature heat source during operation, so that the oil and gas in the outlet pipe 13 are at a higher temperature, thereby preventing the oil and gas from freezing due to low temperature.

[0030] In the above, two blowby gas channels 41 are provided on the exhaust side of the cylinder block 4, including a first blowby gas channel and a second blowby gas channel. An air intake 42 is provided at the upper portion of each of the two blowby gas channels. The middle portion of the oil-gas connecting pipe 12 is connected to the oil-gas separator inlet pipe 11, and the two ends are connected to the air intakes 42 of the first blowby gas channel and the second blowby gas channel, respectively. The crankcase ventilation system is installed on the exhaust side of the cylinder block. Specifically, the blowby gas channel 41, the oil-gas separator 1, the oil-gas connecting pipe 12, the oil-gas separator inlet pipe 11, and the oil-gas separator outlet pipe 13 are installed below the exhaust pipe 2 and the supercharger 3. The high temperature generated by the exhaust pipe 2 and the supercharger 3 during operation radiates the crankcase ventilation system components and pipes, so that in a cold environment, the operating temperature of the oil-gas separator 1 outlet pipe 13 is between 30-70°C, thereby avoiding the risk of freezing and clogging of the crankcase ventilation system pipes.

[0031] Specifically, the inlet of the oil-gas separator 1 faces upward and is connected to the air intake pipe 11. The upper end of the air intake pipe 11 is connected to the middle of the oil-gas connecting pipe 12. A connecting port 123 is provided in the lower middle part of the oil-gas connecting pipe 12 to connect to the air intake pipe 11. The oil-gas connecting pipe 12 is an n-shaped pipe, which includes a straight pipe 122 and connecting air pipes (121, 123) connected to both ends of the straight pipe. The straight pipe 122 and the connecting air pipes (121, 123) at both ends have a smooth transition, and the connecting air pipes (121, 123) at both ends are arranged obliquely downward, so that the oil-gas connecting pipe 12 has an outwardly open structure. And the connecting air pipe and the blowby gas channel are made to form an angle of 20-60 degrees, preferably 30-50 degrees, to improve the permeability of oil and gas. More specifically, the air intake pipe 11 of the oil-gas separator 1 is connected to the lower middle part of the straight pipe 122.

[0032] The air intake pipe 31 is also included, one end of which is connected to the supercharger 3 to deliver the air pressurized by the supercharger 3 to the engine. The outlet pipe 13 of the oil-gas separator 1 is connected to the air intake pipe 31 and follows the pressurized air into the engine for combustion.

[0033] In the present application, an air intake scheme different from that of the prior art is adopted. First, the upper end of the blowby gas channel 41 is sealed to cut off the channel for the blowby gas to flow to the cylinder head cover; secondly, the air intake port 42 is arranged on the side of the upper part of the blowby gas channel 41, rather than the upper end face of the blowby gas channel 41, so that when the oil and gas blow upward along the blowby gas channel 41, part of the engine oil in the oil and gas will fall back, and then the blowby gas channel 41 is used in conjunction with the air intake port 42 to achieve the effect of oil and gas pre-separation; thirdly, the flow rate of the oil and gas entering the oil-gas separator 1 is reduced by controlling the cross-sectional area of ​​the blowby gas channel 41 and the air intake port 42. For example, the air intake port 42 is opened on the two blowby gas channels 41 to increase the flow area of ​​the air intake port 42, the flow rate of the oil and gas is reduced, and the amount of oil carried up the blowby gas channel 41 in the oil and gas can be reduced, which can also enhance the effect of pre-separation. Controlling the oil / gas flow rate entering the intake pipe 11 of the oil / gas separator 1 to less than 1 m / s can significantly reduce the oil content in the oil / gas entering the blowby gas passage. The pre-separation effect of the blowby gas passage 41 further reduces the oil content in the oil / gas entering the intake pipe 11 of the oil / gas separator 1. Existing crankcase ventilation systems do not disclose techniques for reducing the oil content in the oil / gas by controlling the oil / gas flow rate.

[0034] In existing oil-gas separation technology, two oil-gas separators 1 are generally used for oil-gas separation, and some models require various labyrinth designs in the cylinder head cover to achieve the purpose of oil-gas separation, resulting in a very complex structure. However, the present application, on the one hand, prevents the crankcase ventilation system from freezing during operation by installing the crankcase ventilation system on the exhaust side of the cylinder block and using the exhaust pipe 2 and supercharger 3 to radiate the crankcase ventilation system pipes. On the other hand, the oil-gas flow rate is regulated by the blowby gas channel 41 and the air intake 42, significantly reducing the oil content in the oil and gas. Thirdly, the structure of the crankcase ventilation system is simplified, the pre-separation oil-gas separator is omitted, and there is no need to optimize the structure of large components such as the cylinder head. The application cost of the present invention is low. Fourthly, the oil-gas separator 1, the oil-gas separator inlet pipe 11, the oil-gas separator outlet pipe 13, and the blowby gas channel 41 are arranged on the exhaust side, reducing the length of the inlet pipe 11 and the outlet pipe 13, further saving layout costs.

[0035] A method for preventing icing of an engine crankcase ventilation system comprises: installing the crankcase ventilation system on the exhaust side of a cylinder block 4 and below an exhaust pipe 2 and a supercharger 3; and radiating high temperature generated by the exhaust pipe 2 and the supercharger 3 during operation to components and piping of the crankcase ventilation system.

[0036] Those skilled in the art will recognize that numerous variations to the foregoing description are possible, and that the examples and figures are intended only to describe one or more specific implementations.

[0037] Although what is considered to be exemplary embodiments of the present invention has been described and illustrated, it will be understood by those skilled in the art that various changes and substitutions may be made thereto without departing from the spirit of the present invention. In addition, many modifications may be made to adapt a particular situation to the teachings of the present invention without departing from the central concept of the invention described herein. Therefore, the present invention is not limited to the specific embodiments disclosed herein, but rather encompasses all embodiments and their equivalents falling within the scope of the present invention.

Claims

1. An engine crankcase ventilation system for preventing icing, the crankcase ventilation system being mounted on an engine and comprising an oil-gas separator, a blowby gas passage, an intake pipe, and an exhaust pipe. The engine comprises a cylinder block, a cylinder head, an exhaust pipe, and a supercharger. The cylinder block is mounted above the cylinder head, the exhaust pipe is mounted on the cylinder head, and the supercharger is also mounted in the center of the cylinder head. The system is characterized in that: The crankcase exhaust side of the cylinder block is also provided with at least one longitudinally arranged blowby gas channel; the upper end of the blowby gas channel is sealed, and an air intake port is opened on the side of its upper part; the oil-gas separator is installed on the exhaust side of the cylinder block, one end of its intake pipe is connected to the blowby gas channel, and the oil and gas in the crankcase are introduced into the oil-gas separator, and the outlet pipe is connected to the intake end of the supercharger.

2. The engine crankcase ventilation system for preventing icing according to claim 1, wherein: The highest point of the air intake port is located below the sealing point of the upper end of the blowby gas channel.

3. The engine crankcase ventilation system for preventing icing according to claim 1, wherein: The cross-sectional area of ​​the air intake port is smaller than the cross-sectional area of ​​the blowby gas channel in the horizontal direction.

4. The engine crankcase ventilation system for preventing icing according to claim 1, wherein: The supercharger is a mid-mounted supercharger.

5. The engine crankcase ventilation system for preventing icing according to claim 1, wherein: The oil-gas separator outlet pipe is a bent pipe structure, and the outlet pipe includes a horizontal pipe and a vertical pipe. One end of the horizontal pipe is connected to the oil-gas separator outlet, and the other end is connected to the lower end of the vertical pipe. The upper end of the vertical pipe is connected to the air inlet end of the supercharger.

6. The engine crankcase ventilation system for preventing icing according to claim 5, wherein: The horizontal pipe is located directly below the supercharger and extends along the length direction of the supercharger.

7. The engine crankcase ventilation system for preventing icing according to claim 1, wherein: It also includes an oil and gas connecting pipe, and a blowby gas channel is set on the exhaust side of the cylinder body; the middle part of the oil and gas connecting pipe is connected to the oil and gas separator intake pipe, and the two ends are respectively connected to the air intakes of the two blowby gas channels.

8. The engine crankcase ventilation system for preventing icing according to claim 7, wherein: The oil and gas connecting pipe is an N-shaped pipe, which includes a straight pipe and connecting air pipes connected to both ends of the straight pipe. The straight pipe and the connecting air pipes at both ends have a smooth transition.

9. The engine crankcase ventilation system for preventing icing according to claim 8, wherein: Connect the air pipe and the blowby gas channel at an angle of 20-60°.

10. A method for preventing icing of an engine crankcase ventilation system, comprising the crankcase ventilation system of claim 1, characterized in that: The method also includes the following steps: installing the crankcase ventilation system on the exhaust side of the cylinder block and below the exhaust pipe and the supercharger; and radiating the high temperature generated by the exhaust pipe and the supercharger during operation through the intake pipe and the outlet pipe of the oil-gas separator.

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