Gas taking structure and method of engine crankcase ventilation system

Abstract

The invention discloses a gas taking structure of an engine crankcase ventilation system, which comprises a longitudinally arranged blow-by channel arranged on the exhaust side of a cylinder body, the upper port of the blow-by channel is sealed, and the side surface of the upper part of the blow-by channel is provided with a gas taking port communicated with the blow-by channel; the gas taking opening is connected with an inlet of the oil-gas separator through a pipeline; the sectional area of the gas taking opening is smaller than the cross sectional area of the blow-by channel in the horizontal direction. The oil-gas separator has the advantages of being novel in structure, capable of reducing the using number of oil-gas separators, reducing cost and the like.

Description

Technical Field

[0001] The present invention relates to the technical field of crankcase ventilation systems, and in particular to an air intake structure and method of an engine crankcase ventilation system. 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. For example, the existing patent CN213807792U discloses a non-road diesel engine crankcase ventilation system, which uses a pre-oil-gas separator and an external oil-gas separator to separate oil and gas. This requires installing an additional oil-gas separator, which is costly.

[0004] Existing patent document CN107524494A discloses an engine crankcase ventilation system, which adopts a method of providing mutually connected blowby gas channels between the crankcase and the cylinder head.

[0005] 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

[0006] The (main) purpose of the present invention is to propose an air intake structure and method for an engine crankcase ventilation system that regulates the oil and gas flow rate in the blowby gas channel through the blowby gas channel and the air intake port, reduces the oil content in the oil and gas, and reduces the use of a pre-separation oil and gas separator.

[0007] To this end, the present invention provides an air intake structure and method for an engine crankcase ventilation system.

[0008] Preferably, the present invention may also have the following technical features:

[0009] An air intake structure for an engine crankcase ventilation system includes a longitudinally arranged blowby gas channel opened on the exhaust side of a cylinder block, the upper end of the blowby gas channel being sealed, and an air intake port communicating with the blowby gas channel being opened on the upper side surface; the air intake port being connected to an oil-gas separator inlet via a pipeline; and the cross-sectional area of ​​the air intake port being smaller than the horizontal cross-sectional area of ​​the blowby gas channel.

[0010] Furthermore, it also includes an oil and gas connecting pipe, and two blowby gas channels are arranged on the exhaust side, including a first blowby gas channel and a second blowby gas channel. The upper parts of the two blowby gas channels are respectively provided with air intakes connected to the two ends of the oil and gas connecting pipe; the middle part of the oil and gas connecting pipe is connected to the oil and gas separator inlet pipe.

[0011] Furthermore, the oil-gas connecting pipe and the oil-gas separator air inlet pipe are both located below the engine exhaust pipe and the supercharger.

[0012] Furthermore, the oil and gas connecting pipe is an N-shaped pipe, which includes a straight pipe and connecting air pipes integrated at both ends of the straight pipe, and the straight pipe and the connecting air pipes at both ends have a smooth transition.

[0013] Furthermore, the connecting air pipe and the blowby gas channel form an angle of 20-60 degrees.

[0014] Furthermore, the angle is 30 to 50 degrees.

[0015] Furthermore, the oil and gas flow rate entering the air inlet pipe of the oil and gas separator is within 1 m / s.

[0016] Furthermore, the crankcase ventilation system is provided with only one oil-gas separator.

[0017] A method for taking in air from an air intake structure of an engine crankcase ventilation system as described above, wherein a plurality of blowby gas passages are designed according to the displacement of the engine, and the oil and gas flow rate of the crankcase oil and gas entering the blowby gas passages is adjusted by controlling the total flow area of ​​the air intake ports and the cross-sectional area of ​​the blowby gas passages, so that the oil and gas flow rate is less than 1 m / s; and the air intake port is then directly or indirectly connected to the air intake port by an air intake pipe of the oil-gas separator.

[0018] Furthermore, the blowby gas passage and the oil-gas separator are both arranged on the exhaust side of the cylinder block.

[0019] The beneficial effects of the present invention compared with the prior art include: on the one hand, the present invention regulates the oil and gas flow rate through the blowby gas channel and the air intake, thereby significantly reducing the oil content in the oil and gas; on the other hand, it simplifies the structure of the crankcase ventilation system, omits the pre-separation oil and gas separator, and does not require optimization of the structure of large parts such as the cylinder head. The application cost of the present invention is low. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is a schematic diagram of the application of the present invention on an engine.

[0021] Figure 2 It is a schematic diagram of the main structure of the present invention.

[0022] Figure 3 It is a partial cross-sectional view of the present invention.

[0023] Figure 4 This is a first-perspective view of the oil and gas connecting pipe of the present invention.

[0024] Figure 5 This is a second viewing angle diagram of the oil and gas connecting pipe of the present invention. DETAILED DESCRIPTION

[0025] 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.

[0026] 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 specifically specified.

[0027] like Figures 1 to 3 The illustrated air intake structure of an engine crankcase ventilation system includes a longitudinally arranged blowby gas channel 41 opened on the exhaust side of the cylinder block 4. The upper end of the blowby gas channel 41 is sealed, and an air intake port 42 connected to the blowby gas channel 41 is opened on the upper side. The air intake port 42 is connected to the inlet of the oil-gas separator 1 via a pipeline. The cross-sectional area of ​​the air intake port 42 is smaller than the horizontal cross-sectional area of ​​the blowby gas channel 41. The flow rate of the oil and gas entering the blowby gas channel 41 is regulated by the cross-sectional areas of the air intake port 42 and the blowby gas channel 41, thereby reducing the oil content of the oil and gas entering the oil-gas separator 1. Preferably, the highest point of the air intake port 42 is located below the seal of the upper end of the blowby gas channel 41.

[0028] Furthermore, it also includes an oil-gas connecting pipe 12. Two blowby gas passages 41 are provided on the exhaust side of the cylinder block 4, including a first blowby gas passage 41 and a second blowby gas passage. The upper portions of the two blowby gas passages are each provided with an air intake 42 for connection to the oil-gas connecting pipe 12. The middle portion of the oil-gas connecting pipe 12 is connected to the oil-gas separator inlet pipe 11, and the ends are respectively connected to the air intakes 42 of the first and second blowby gas passages. In this way, oil and gas from the crankcase enter the oil-gas connecting pipe 12 from the air intake 42 via the two blowby gas passages, and then flow through the oil-gas separator inlet pipe 11 to the oil-gas separator 1. Moreover, the oil-gas connecting pipe 12 and the oil-gas separator inlet pipe 11 are both located below the exhaust pipe 2 and the supercharger 3. Due to the limited usable space of the cylinder block 4, it is difficult to establish a larger air intake to reduce the oil and gas flow rate. Therefore, two blowby gas channels 41 are designed on the exhaust side of the cylinder block 4, and each blowby gas channel is designed with an air intake port, thereby increasing the cross-sectional area of ​​the air intake port to reduce the oil and gas flow rate and improve the oil and gas separation effect.

[0029] Combine Figure 4-5 The oil-gas separator 1 is installed on the exhaust side of the cylinder block 4 and below the oil-gas connecting pipe 12. The inlet of the oil-gas separator 1 is upward and connected to the intake pipe 11. The upper end of the intake pipe 11 is connected to the middle of the oil-gas connecting pipe 12. A connecting port 124 is provided in the middle of the lower side of the oil-gas connecting pipe 12 to connect to the 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) integrated at both ends of the straight pipe 122. 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 12 and the blowby gas channel 41 form an angle of 20-60°. Preferably, the angle is 30-50°, for example 40°, to improve the permeability of oil and gas. More specifically, the air inlet pipe 11 of the oil-gas separator 1 is connected to the lower middle portion of the straight pipe 122 .

[0030] Refer again Figure 1 , further comprising an air intake pipe 31, one end of which is connected to the supercharger 3, and delivers 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 of the supercharger 3, and follows the pressurized air into the engine for combustion.

[0031] 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 channel 41 to flow toward the cylinder head cover; secondly, the air intake port 42 is arranged on the side surface of the upper part of the blowby gas channel 41, rather than the upper end surface of the blowby gas channel 41, so that the oil and gas are blocked when they move upward along the blowby gas channel 41, and part of the engine oil in the oil and gas will fall back into the crankcase, reducing the engine oil content in the oil and gas, thereby achieving the effect of oil and gas pre-separation; thirdly, the cross-sectional area of ​​the air intake port 42 is further controlled to reduce the flow rate of the oil and gas entering the oil-gas separator 1. For example, air intake ports 42 are opened on two blowby gas channels 41, which not only increases the flow area (cross-sectional area) of the blowby gas channel 41, but also increases the flow area of ​​the air intake port 42, so that the oil and gas flow rate entering the blowby gas channel 41 is reduced, the amount of engine oil in the oil and gas brought to the blowby gas channel 41 is reduced, and the effect of pre-separation is further enhanced. Controlling the oil / gas flow velocity entering the oil / gas separator intake pipe 11 to less than 1 m / s significantly reduces the oil content in the oil / gas entering the blowby gas passage 41. The pre-separation effect of the blowby gas passage 41 further reduces the oil content in the oil / gas entering the oil / gas separator intake pipe 11. Existing crankcase ventilation systems do not disclose techniques for reducing the oil content in the oil / gas by controlling the oil / gas flow velocity.

[0032] In existing oil-gas separation technology, two oil-gas separators are generally used for oil-gas separation, and some models require various labyrinth designs in the cylinder head to achieve the purpose of oil-gas separation, which is very complex. However, the present application, on the one hand, installs the crankcase ventilation system on the exhaust side of the cylinder block 4, and utilizes the exhaust pipe 2 and supercharger 3 to radiate heat to the crankcase ventilation system pipes, thereby preventing the crankcase ventilation system pipes from freezing during operation; 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 the optimization of the structure of large components such as the cylinder head is not required. The application cost of the present invention is low.

[0033] A method for extracting air from an engine crankcase ventilation system includes the aforementioned air extraction structure. A plurality of blowby gas passages 41 are designed according to the engine's displacement. The flow rate of crankcase oil and gas entering the blowby gas passages 41 is adjusted by controlling the cross-sectional areas of the air extraction port 42 and the cross-sectional areas of the blowby gas passages 41. An oil-gas separator 1 is mounted on the exhaust side of the cylinder block 4, and the air extraction port 42 is directly or indirectly connected to the oil-gas separator's intake pipe 11. Preferably, the oil-gas flow rate entering the blowby gas passages 41 is less than 1 m / s.

[0034] 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.

[0035] 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 air intake structure for an engine crankcase ventilation system, characterized by: It includes a longitudinally arranged blowby gas channel opened on the exhaust side of the cylinder body, the upper end of the blowby gas channel is sealed, and an air intake port connected to the blowby gas channel is opened on the side of the upper part; the air intake port is connected to the oil-gas separator inlet through a pipeline; the cross-sectional area of ​​the air intake port is smaller than the horizontal cross-sectional area of ​​the blowby gas channel.

2. The air intake structure of the engine crankcase ventilation system according to claim 1, characterized in that: It also includes an oil and gas connecting pipe, and two blowby gas channels are arranged on the exhaust side, including a first blowby gas channel and a second blowby gas channel. The upper parts of the two blowby gas channels are respectively provided with air intakes connected to the two ends of the oil and gas connecting pipe; the middle part of the oil and gas connecting pipe is connected to the oil and gas separator inlet pipe.

3. The air intake structure of the engine crankcase ventilation system according to claim 2, characterized in that: The oil-gas connecting pipe and the oil-gas separator air inlet pipe are both located below the engine exhaust pipe and the supercharger.

4. The air intake structure of the engine crankcase ventilation system according to claim 2, characterized in that: The oil and gas connecting pipe is an N-shaped pipe, which includes a straight pipe and connecting air pipes integrated at both ends of the straight pipe. The straight pipe and the connecting air pipes at both ends have a smooth transition.

5. The air intake structure of the engine crankcase ventilation system according to claim 4, characterized in that: The connecting air pipe and the blowby gas channel form an angle of 20-60 degrees.

6. The air intake structure of the engine crankcase ventilation system according to claim 5, characterized in that: The angle is 30 to 50 degrees.

7. The air intake structure of the engine crankcase ventilation system according to claim 2, characterized in that: The oil and gas flow rate entering the oil and gas separator inlet pipe is within 1m / s.

8. The air intake structure of the engine crankcase ventilation system according to claim 1, characterized in that: The crankcase ventilation system is provided with only one oil-gas separator.

9. An air intake method for an air intake structure of an engine crankcase ventilation system according to claim 1, characterized in that: A number of blowby gas channels are designed according to the displacement of the engine. The oil and gas flow rate of the crankcase oil and gas entering the blowby gas channel is adjusted by controlling the total flow area of ​​the air intake and the cross-sectional area of ​​the blowby gas channel, so that the oil and gas flow rate is less than 1m / s; and the air intake pipe of the oil-gas separator is directly or indirectly connected to the air intake.

10. The gas extraction method according to claim 9, wherein: The blowby gas passage and the oil-gas separator are both arranged on the exhaust side of the cylinder block.

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