An oil-gas separation structure with the function of continuously variable flow cross-section throughout the whole process

Abstract

An embodiment of the present application provides an oil-gas separation structure with a function of continuously variable flow cross-section. An impactor is installed in the oil-gas separation channel of the valve cover, and a pressure regulating valve is arranged in the impact cavity of the impactor; an adjusting cavity communicating with the intake end of the oil-gas separation channel and the impact cavity is formed in the valve seat of the pressure regulating valve, and the valve body is movably installed in the adjusting cavity; when the flow rate of the oil-gas mixture is large, a large pressure difference will be generated between the front and rear ends of the valve body. The valve body can move under the action of the pressure difference, so that the pressure loss of the separation structure is maintained within the designed range, and it will not generate too high pressure loss under too high flow conditions. It can also avoid oil leakage caused by the inability of the back-end oil return valve to open, and avoid the situation of "burning oil" in the engine.

Description

Technical Field

[0001] The present invention relates to the field of vehicle engines, and particularly to an oil-gas separation structure with a continuously variable flow cross-section function. Background Art

[0002] When the engine is operating, the high-pressure combustible mixture and the burned gas in the combustion chamber will more or less leak into the crankcase through the gap between the piston group and the cylinder, causing blow-by. The components of blow-by are unburned fuel gas, water vapor, exhaust gas, etc., which will dilute the engine oil, reduce the service performance of the engine oil, and accelerate the oxidation and deterioration of the engine oil. The engine oil mixed with other impurities is likely to block the oil passage; the acidic gas in the exhaust gas mixed into the lubrication system will cause corrosion and accelerated wear of the engine parts; blow-by will also cause the pressure in the crankcase to be too high and damage the seal of the crankcase, causing engine oil leakage. Therefore, in current automobile designs, a crankcase ventilation system design is adopted to solve the above problems. As a key part of the crankcase ventilation system, the oil-gas separator functions to separate the engine oil from the mixture in the crankcase emissions and return it to the oil pan, avoiding adverse consequences such as increased combustion chamber carbon deposition, unstable idling, and excessive exhaust emissions caused by "oil burning" in the vehicle.

[0003] Currently, most common crankcase ventilation systems adopt a structure with a passive oil-gas separator arranged in the valve cover. The disadvantage of this structure is that as the engine speed changes, the blow-by volume also changes: according to the principle of fluid mechanics, the higher the blow-by volume, the faster the flow rate, and the greater the pressure loss inside the valve cover, resulting in a greater pressure difference between the inlet and outlet ends of the valve cover; according to Pascal's "barrel bursting" experiment, the internal pressure of a liquid is related to the height. Therefore, if the pressure difference is too large, the required oil return height will be higher, and it is more likely to cause poor oil return. When the gas flows, it is easy to carry engine oil into the engine, affecting the separation efficiency. On the other hand, too large a pressure difference will also affect the internal pressure of the crankcase, and this situation is most likely to occur in large-displacement engines.

[0004] Therefore, it is necessary to develop an oil-gas separation structure with a continuously variable flow cross-section function to solve the above technical problems. Summary of the Invention

[0005] An embodiment of the present invention provides an oil-gas separation structure with a continuously variable flow cross-section function, which can keep the pressure difference between the inlet and outlet ends of the valve cover within a certain set range, thereby solving the technical problem that the oil-gas separation efficiency is affected due to too large a pressure difference between the inlet and outlet ends of the valve cover.

[0006] An oil-gas separation structure with a continuously variable flow cross-section function provided by an embodiment of the present invention includes:

[0007] Valve cover, an oil and gas separation channel is formed inside the valve cover, and an oil return groove is formed at the air outlet end of the oil and gas separation channel;

[0008] Impactor, the impactor is installed in the oil and gas separation channel, and an impact cavity that is in fluid communication with the oil and gas separation channel and the oil return groove is formed inside the impactor; and

[0009] Pressure regulating valve, the pressure regulating valve includes a valve seat and a valve body; the valve seat is installed in the impact cavity, and an adjustment cavity for accommodating the valve body is formed inside the valve seat; an air inlet and an air outlet are provided in the adjustment cavity, the air inlet is communicated with the air inlet end of the oil and gas separation channel, and the air outlet is communicated with the impact cavity;

[0010] The valve body is movably installed in the adjustment cavity and can move from a first position to a second position under the action of the pressure difference between the front and rear ends of the valve body; when the valve body is in the first position, the valve body closes the air inlet; when the valve body is in the second position, a flow channel for the oil and gas mixture to pass through is formed between the valve body and the air inlet, the flow channel is communicated with the impact cavity through the air outlet, and a filter element for oil and gas separation is provided at the air outlet.

[0011] Optionally, a valve rod is connected to the side of the valve body facing the air inlet, a guide sleeve adapted to the valve rod is formed at the air inlet, and the valve rod is movably installed in the guide sleeve; a spring is sleeved on the valve rod, and the spring is used to apply an elastic force to the valve body to move it from the second position to the first position.

[0012] Optionally, a magazine is installed at the end of the valve rod away from the valve body, and the two ends of the spring are respectively connected to the guide sleeve and the magazine.

[0013] Optionally, the impactor is provided with a cover plate, one side of the cover plate is fixedly connected to the impactor by clamping, and a plurality of positioning protrusions are provided on the other side of the cover plate, and the positioning protrusions are abutted against the valve cover.

[0014] Optionally, the impactor is provided with a bottom plate, and the bottom plate is fixedly connected to the valve cover.

[0015] Optionally, an air inlet hole communicated with the air inlet is opened on the bottom plate, a welding rib is arranged between the air inlet hole and the oil return groove, and the welding rib is fixedly connected to the valve cover.

[0016] Optionally, baffle edges are provided on both sides of the welding rib.

[0017] Optionally, the bottom plate extends above the oil return groove, and an oil return hole communicated with the oil return groove is opened on the bottom plate.

[0018] Optionally, an oil baffle is provided at one end of the bottom plate close to the gas outlet end of the oil-gas separation channel, and a rib plate is provided at the other end of the bottom plate; the rib plate is fixedly connected to the valve cover.

[0019] Optionally, a plurality of impact baffles are provided between the inlet end of the oil-gas separation channel and the impactor.

[0020] The embodiment of the present invention has the following beneficial effects:

[0021] An impactor is installed in the oil-gas separation channel of the valve cover, and a pressure regulating valve is provided in the impact cavity of the impactor; an adjustment cavity communicating with the inlet end of the oil-gas separation channel and the impact cavity is formed in the valve seat of the pressure regulating valve, and the valve body is movably installed in the adjustment cavity; when the flow rate of the oil-gas mixture is large, a large pressure difference will be generated between the front and rear ends of the valve body, and the valve body can move under the action of the pressure difference, so that the pressure loss of the separation structure is maintained within the design range, and it will not generate too high pressure loss under too high flow conditions. It can also avoid oil leakage caused by the inability to open the back-end oil return valve, and avoid the situation of "burning oil" in the engine. At the same time, reasonable flow channels are designed in the impactor and the pressure regulating valve, which can guide the flow direction of the separated gas and oil, and avoid the separated oil being carried by the gas again, resulting in a reduction in separation efficiency. Description of the Drawings

[0022] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following will briefly introduce the drawings required for the description of the embodiments. Obviously, the following drawings are only some embodiments of the present invention. For those skilled in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0023] Figure 1 Cross-section of the embodiment of the present invention Figure 1 (The valve body is in the first position);

[0024] Figure 2 Cross-section of the embodiment of the present invention Figure 2 (The valve body is in the second position);

[0025] Figure 3 Cross-sectional view of the valve body in the embodiment of the present invention;

[0026] Figure 4 Exploded structure diagram of the impactor in the embodiment of the present invention;

[0027] Figure 5 Internal structure diagram of the impactor in the embodiment of the present invention;

[0028] Figure 6This is a schematic structural view of the impactor bottom plate in the embodiments of the present invention;

[0029] The numbers in the figure represent:

[0030] 1. Valve cover; 2. Oil-gas separation channel; 21. Impact baffle; 3. Oil return groove; 4. Impactor; 41. Through hole; 42. Cover plate; 421. Positioning protrusion; 43. Bottom plate; 431. Air inlet hole; 432. Material blocking edge; 433. Welding rib; 434. Oil return hole; 435. Oil baffle; 436. Rib plate; 5. Pressure regulating valve; 51. Valve seat; 511. Air inlet; 512. Air outlet; 513. Filter element; 514. Installation bone position; 52. Valve body; 53. Flow channel; 54. Valve rod; 55. Guide sleeve; 56. Spring; 57. Magazine. Specific embodiments

[0031] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without making creative efforts belong to the scope of protection of the present invention. In addition, it should be understood that the specific embodiments described herein are only used to illustrate and explain the present invention, and are not used to limit the present invention. In the present invention, unless otherwise stated, the orientation words such as "left", "right", "top" and "bottom" usually refer to the orientation in the actual use or working state of the device, specifically the drawing direction in the drawings, and "inside" and "outside" refer to the outline of the device.

[0032] In addition, terms such as "first", "second", etc. are only used for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the quantity of the indicated technical features. Thus, features defined with "first", "second", etc. may explicitly or implicitly include one or more features. In the description of the present invention, the meaning of "a plurality" is two or more, unless otherwise specifically defined.

[0033] Please refer to Figure 1 , Figure 2As shown in the figure, an embodiment of the present invention provides an oil-gas separation structure with a function of continuously variable flow cross-section, including a valve cover 1. An oil-gas separation channel 2 is formed inside the valve cover 1. The intake end of the oil-gas separation channel 2 is connected to the engine crankcase (not shown in the figure), so that the oil-gas mixture discharged from the engine crankcase can enter the oil-gas separation channel 2 for separation. An oil return groove 3 is formed at the outlet end of the oil-gas separation channel 2 for collecting the separated engine oil to realize the recovery and reuse of the engine oil. An oil return valve that is unidirectionally connected to the oil return channel is installed in the oil return groove 3. The oil return valve needs a certain pressure difference to open for oil discharge, so it is necessary to avoid too high pressure loss in the separation structure.

[0034] An impactor 4 is installed between the intake end and the outlet end of the oil-gas separation channel 2. An impact chamber that is fluidly connected to the oil-gas separation channel 2 and the oil return groove 3 is formed inside the impactor 4. In other words, corresponding through holes 41 are designed on the side wall of the impactor 4 as the flow channels for gas and engine oil during oil-gas separation, so that the oil-gas mixture can enter the impactor 4 for separation. The separated pure gas can enter the oil-gas separation channel 2 and be discharged from the outlet end of the oil-gas separation channel 2, and the separated engine oil can flow into the oil return groove 3 for recovery and reuse.

[0035] To avoid excessive pressure difference between the inlet and outlet ends of the impact chamber, which may cause too high a height required for engine oil return and result in oil leakage, as Figures 3 - 5 shown, a pressure regulating valve 5 is provided in the impact chamber in this embodiment. The pressure regulating valve 5 includes a valve seat 51 and a valve body 52. The valve seat 51 is installed in the impact chamber, and an adjustment chamber for accommodating the valve body 52 is formed inside the valve seat 51. The adjustment chamber is provided with an air inlet 511 and an air outlet 512. The air inlet 511 is connected to the intake end of the oil-gas separation channel 2, and the air outlet 512 is connected to the impact chamber. The valve body 52 is movably installed in the adjustment chamber and can move from the first position to the second position under the action of the pressure difference between the front and rear ends of the valve body 52.

[0036] Specifically, when the valve body 52 is in the first position (as Figure 1 shown), the valve body 52 closes the air inlet 511, preventing the oil-gas mixture from passing through. When the valve body 52 is in the second position (as Figure 2As shown, a flow passage 53 for the oil-gas mixture to pass through is formed between the valve body 52 and the air inlet 511. The flow passage 53 is connected to the impact chamber through the air outlet 512, and a filter element 513 is provided at the air outlet 512. The oil-gas mixture can enter the impact chamber after oil-gas separation through the filter element 513. That is to say, when there is a certain pressure difference P0 - P1 between the front and rear ends of the valve body 52, the valve body 52 can move upward under the action of the pressure difference, so that the air inlet 511 is communicated with the air outlet 512, so that the oil-gas mixture can be oil-gas separated through the filter element 513. It can be understood that the size of the flow passage 53 (i.e., the moving distance of the valve body 52) can be adjusted with the change of the pressure difference P0 - P1 between the front and rear ends of the valve body 52, so as to appropriately increase the flow cross-section in the case of a high-flow mixture, thereby adjusting the pressure loss of the separation structure, so that the pressure difference P0 - P1 between the front and rear ends of the valve body 52 can be within a certain set range, ensuring that the gas has a certain kinetic energy to pass through the separation structure, while avoiding excessive pressure loss of the oil-gas separation structure and avoiding oil leakage caused by too high an oil return height, thereby improving the oil-gas separation efficiency. In addition, in order to increase the gas flow area and avoid the pressure loss caused by too small a flow area and an increase in the gas mixture volume, two air outlets 512 are provided in this embodiment. A plurality of mounting bosses 514 are provided on the periphery of the two air outlets 512 for positioning and clamping the filter element 513. For reference, in this embodiment, a felt is used as the filter element 513. The felt has a tight structure and small pores, and has excellent filtering and oil-containing effects.

[0037] Specifically, in this embodiment, a valve rod 54 is connected to the bottom of the valve body 52 (i.e., the side facing the air inlet 511), and a guide sleeve 55 adapted to the valve rod 54 is formed at the air inlet 511. The valve rod 54 is movably installed in the guide sleeve 55. A spring 56 is sleeved on the valve rod 54, and the spring 56 can apply an elastic force to the valve body 52 to move it from the second position to the first position. That is to say, the spring 56 is designed with a certain pre-compression amount. When the pressure difference P0 - P1 is greater than the elastic force of the spring 56, the valve body 52 can move under the action of the pressure difference, so as to realize the automatic opening of the pressure regulating valve 5. When the pressure difference P0 - P1 is less than the elastic force of the spring 56, the valve body 52 can move to the first position under the action of the spring 56, so as to realize the automatic adjustment of the pressure regulating valve 5. When designing, the range of the pressure difference P0 - P1 can be set by changing the elastic force of the spring 56.

[0038] Further, a magazine 57 is installed at the bottom end of the valve stem 54. Both ends of the spring 56 are respectively connected to the guide sleeve 55 and the magazine 57, so that the spring 56 has a certain pre-compression amount. The spring 56 should be made of a material with excellent performance, so that the spring 56 has good extreme temperature, anti-fatigue life, stiffness and permanent deformation performance. In addition, a reasonable clearance should be designed during the assembly of the spring 56 to improve the stability of the spring 56. The spring 56 has low movement noise and can be adjusted according to customer requirements, and has good applicability. As a reference, as Figure 3 shown, in this embodiment, a certain pouring angle is designed in the assembly of the valve stem 54 and the magazine 57, which improves the assembly between parts; during assembly, the hanging platform on the magazine 57 is engaged with the groove on the valve stem 54, and a certain interference amount and wall thickness are adopted in the design of the magazine 57 and the valve stem 54. Through CAE analysis and product tests, this assembly is convenient and reliable, and will not fall off under extreme working conditions. The magazine 57 is precision injection molded, and the surface of the part is smooth and free of burrs and other defects, which improves the product cleanliness.

[0039] In addition, in order to ensure the sealing performance when the valve body 52 contacts the air inlet 511, a rubber part is also provided at the bottom of the valve body 52 in this embodiment. The rubber part is made of a material with excellent performance in all aspects, meeting the requirements for the normal operation of parts under extreme environments. The valve body 52 is made of plastic material and integrally injection molded with the rubber part. Precision injection molding makes the surface of the part smooth and free of burrs and other defects, which improves the product cleanliness. The striker 4 and the valve seat 51 can also be integrally formed by precision injection molding, using high-performance plastic materials, so that it has flame retardant performance, oil resistance, heat aging resistance and low temperature performance, and also needs to have many material characteristics such as chemical corrosion resistance.

[0040] Further, please refer to Figures 4 - 6 shown, a cover plate 42 is provided at the top of the striker 4, and a bottom plate 43 is provided at the bottom. Among them, the bottom plate 43 is fixedly connected to the valve cover 1. Specifically, in this embodiment, the bottom side of the cover plate 42 is fixedly connected to the striker 4 through structures such as buckles, and the top side of the cover plate 42 abuts against the valve cover 1 through four positioning protrusions 421 for support and positioning, so as to prevent the components from moving up and down due to engine vibration after the cover plate 42 is installed.

[0041] An intake hole 431 communicating with the intake port 511 is formed in the bottom plate 43 to allow the oil-gas mixture at the intake end of the oil-gas separation channel 2 to enter. A welding rib 433 is arranged between the intake hole 431 and the oil return groove 3. The welding rib 433 is fixedly connected to the valve cover 1 by welding or other means, which can not only realize the positioning and fixing of the impactor 4, but also prevent the unseparated oil-gas mixture from leaking into the oil return groove 3 or the overflow material in the oil return groove 3 from leaking into the structure. For reference, baffle edges 432 are arranged on both sides of the welding rib 433 in this embodiment, which can prevent the overflow material from flowing into the separation channel.

[0042] Furthermore, the bottom plate 43 extends above the oil return groove 3, and an oil return hole 434 communicating with the oil return groove 3 is formed in the bottom plate 43. The separated engine oil can flow to the bottom plate 43 under the action of gravity and flow into the oil return groove 3 through the oil return hole 434. In addition, in this embodiment, an oil baffle 435 is arranged at one end of the bottom plate 43 close to the outlet end of the oil-gas separation channel 2 to block the separated engine oil and prevent the engine oil from being carried by the gas again. A rib plate 436 is also arranged at the other end of the bottom plate 43. The rib plate 436 is fixedly connected to the valve cover 1, which can not only realize the positioning and fixing of the impactor 4, but also block the unseparated oil-gas mixture to prevent the unseparated oil-gas mixture from directly flowing into the outlet end of the oil-gas separation channel 2. For reference, in this embodiment, the rib plate 436 and the groove on the valve cover 1 are assembled and positioned by clearance press-fitting and then welded and fixed. This assembly method is simple to operate and can provide accurate positioning for subsequent welding.

[0043] In this embodiment, a plurality of impact baffles 21 are further arranged between the intake end of the oil-gas separation channel 2 and the impactor 4. Please refer to Figure 1 the direction of the arrow shown in. When the engine speed is low, the blow-by gas volume in the crankcase is small. The oil-gas mixture in the crankcase flows into the oil-gas separation channel 2 in the valve cover 1. After being roughly separated by the plurality of impact baffles 21, it flows to the bottom of the impactor 4. Since the blow-by gas volume is small at this time, the pressure difference P0 - P1 between the front and rear ends of the valve body 52 is less than the elastic force of the spring 56. Therefore, the valve body 52 is in a sealed contact state with the intake port 511, and the pressure regulating valve 5 is closed; as Figure 2 the direction of the arrow shown in. When the blow-by gas volume flow rate remains unchanged, the pressure difference P0 - P1 between the front and rear ends of the valve body 52 continuously increases due to the closing of the pressure regulating valve 5. When the pressure difference P0 - P1 is greater than the elastic force of the spring 56, the pressure regulating valve 5 opens for pressure relief, and the oil-gas mixture is finely separated through the filter element 513; then the pressure difference P0 - P1 between the front and rear ends of the valve body 52 decreases. When the pressure difference P0 - P1 decreases to less than the elastic force of the spring 56, the valve body 52 moves in the direction of the first position, causing the pressure regulating valve 5 to close, and so on.

[0044] Similarly, when the engine speed increases, the amount of blow-by gas in the crankcase increases, and the pressure difference P0 - P1 between the front and rear ends of the valve body 52 increases accordingly. When the pressure difference P0 - P1 is greater than the elastic force of the spring 56, the valve body 52 moves upward under the action of the pressure difference, and the pressure regulating valve 5 opens. A flow passage 53 for the oil-gas mixture to pass through is formed between the valve body 52 and the air inlet 511. The oil-gas mixture can pass through the filter element 513 at a certain flow rate for fine separation. The separated gas enters the oil-gas separation channel 2 after colliding in the impact chamber and is discharged from the outlet end of the oil-gas separation channel 2. The separated oil flows into the oil return tank 3 for recovery and reuse. Conversely, when the engine speed decreases or idles, the pressure difference P0 - P1 decreases, and the valve body 52 moves downward to balance the pressure difference P0 - P1 between the front and rear ends of the valve body 52 by reducing the effective flow area of the flow passage 53.

[0045] In this article, specific examples are used to elaborate on the principles and implementation manners of the present invention. The description of the above embodiments is only used to help understand the technical solution and its core idea of the present invention; those of ordinary skill in the art should understand that they can still modify the technical solutions recorded in the foregoing embodiments, or perform equivalent replacements on some of the technical features; and these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. An oil-gas separation structure with a function of continuously variable flow cross-section throughout the whole process, characterized in that, it includes: a valve cover, an oil-gas separation channel is formed inside the valve cover, and an oil return groove is formed at the air outlet end of the oil-gas separation channel; an impactor, the impactor is installed in the oil-gas separation channel, and an impact cavity is formed inside the impactor, which is in fluid communication with the oil-gas separation channel and the oil return groove; and a pressure regulating valve, the pressure regulating valve includes a valve seat and a valve body; the valve seat is installed in the impact cavity, and an adjustment cavity for accommodating the valve body is formed inside the valve seat; the adjustment cavity is provided with an air inlet and an air outlet, the air inlet is communicated with the air inlet end of the oil-gas separation channel, and the air outlet is communicated with the impact cavity; the valve body is movably installed in the adjustment cavity and can move from a first position to a second position under the action of the pressure difference between the front and rear ends of the valve body; when the valve body is in the first position, the valve body closes the air inlet; when the valve body is in the second position, a flow channel for the oil-gas mixture to pass through is formed between the valve body and the air inlet, the flow channel is communicated with the impact cavity through the air outlet, and a filter element for oil-gas separation is arranged at the air outlet; a valve rod is connected to the side of the valve body facing the air inlet, a guide sleeve adapted to the valve rod is formed at the air inlet, and the valve rod is movably installed in the guide sleeve; a spring is sleeved on the valve rod, and the spring is used to apply an elastic force to the valve body to move it from the second position to the first position; a magazine is installed at the end of the valve rod away from the valve body, and the two ends of the spring are respectively connected to the guide sleeve and the magazine; the impactor is provided with a bottom plate, the bottom plate is fixedly connected to the valve cover; an air inlet hole communicated with the air inlet is formed on the bottom plate, a welding rib is arranged between the air inlet hole and the oil return groove, and the welding rib is fixedly connected to the valve cover; baffle edges are arranged on both sides of the welding rib; the bottom plate extends above the oil return groove, and an oil return hole communicated with the oil return groove is formed on the bottom plate.

2. An oil-gas separation structure with a function of continuously variable flow cross-section throughout the whole process according to claim 1, characterized in that: the impactor is provided with a cover plate, one side of the cover plate is fixedly connected to the impactor by clamping, and a plurality of positioning protrusions are arranged on the other side of the cover plate, and the positioning protrusions are abutted against the valve cover.

3. An oil-gas separation structure with a function of continuously variable flow cross-section throughout the whole process according to claim 1, characterized in that: an oil baffle is arranged at one end of the bottom plate close to the air outlet end of the oil-gas separation channel, and a rib plate is arranged at the other end of the bottom plate; the rib plate is fixedly connected to the valve cover.

4. An oil-gas separation structure with a function of continuously variable flow cross-section throughout the whole process according to any one of claims 1-3, characterized in that: a plurality of impact baffles are arranged between the air inlet end of the oil-gas separation channel and the impactor.

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