PCV valve and internal combustion engine crankcase forced ventilation system comprising same

Abstract

The invention provides a PCV and an internal combustion engine crankcase forced ventilation system comprising the PCV.The PCV comprises a valve body, a first sleeve structure arranged on the valve body in a sleeving mode and a second sleeve structure arranged on the valve body in a sleeving mode, a first cavity and a second cavity are formed in the valve body, the first cavity is communicated with the second cavity through a first through hole, and the second cavity is communicated with the second cavity through a second through hole. A valve element structure and a first elastic structure arranged on the valve element structure in a sleeving mode are arranged in the first cavity, the first sleeve structure comprises a first shell arranged at the input end of the valve body in a sleeving mode, an input cavity formed in the first shell and a second through hole, and a high-speed fan assembly is arranged in the input cavity. The second sleeve structure comprises a second shell arranged at the output end of the valve body in a sleeving mode, an output cavity formed in the second shell and a base plate structure, a third through hole for communicating the output cavity with the interior of the second cavity is formed in the base plate structure, and a second elastic structure is arranged on the side, facing the second cavity, of the base plate structure.

Description

Technical Field

[0001] The present invention relates to the technical field of internal combustion engines, and particularly to a PCV valve and a positive crankcase ventilation system for an internal combustion engine containing the PCV valve. Background Art

[0002] The PCV valve (Positive Crankcase Ventilation Valve) is an important component used to control crankcase ventilation in modern internal combustion engines. Its main function is to reintroduce the exhaust gas in the crankcase into the engine intake system for combustion, so as to reduce the emission of harmful gases and improve the fuel economy of the engine. With the increasingly strict environmental protection regulations and the continuous progress of engine technology, the design and performance requirements of the PCV valve are also constantly improving.

[0003] In the prior art, the traditional PCV valve usually consists of a valve body, a valve core and an elastic element, and its working principle is to control the gas flow through the movement of the valve core; however, when the traditional PCV valve operates at high load or high speed, there are often problems such as unstable air flow, slow response speed of the valve core and insufficient durability; in addition, due to the complexity and variability of the engine operating conditions, the traditional PCV valve has poor adaptability when dealing with different operating conditions, which easily leads to unsatisfactory ventilation effect, thereby affecting the performance and emission of the engine; and the traditional PCV valve is easily interfered by the pressure of the fuel mixture gas, and it is difficult to guarantee the control accuracy, resulting in too high crankcase pressure, damaging the seals such as engine oil seals and gaskets, and causing oil leakage. Summary of the Invention

[0004] Based on this, the object of the present invention is to provide a PCV valve and a positive crankcase ventilation system for an internal combustion engine containing the PCV valve, which can effectively solve the above deficiencies in the prior art.

[0005] A PCV valve includes a valve body, a first sleeve structure sleeved on the input end of the valve body, and a second sleeve structure sleeved on the output end of the valve body. On one side of the valve body facing the first sleeve structure, a first cavity is provided. On one side of the valve body facing the second sleeve structure, a second cavity is provided. The first cavity is communicated with the second cavity through a first through hole. A valve core structure and a first elastic structure sleeved on the valve core structure are provided in the first cavity. The first sleeve structure includes a first housing sleeved on the input end of the valve body, an input cavity provided in the first housing, and a second through hole for communicating the input cavity with the inside of the first cavity. A high-speed fan assembly for increasing the flow rate of the exhaust gas is provided in the input cavity. The second sleeve structure includes a second housing sleeved on the output end of the valve body, an output cavity provided in the second housing, and a spacer structure provided between the output cavity and the second cavity. A third through hole for communicating the output cavity with the inside of the second cavity is provided in the spacer structure. A second elastic structure is provided on one side of the spacer structure facing the second cavity.

[0006] Compared with the prior art, the beneficial effects of the present invention are as follows: When the engine runs at high speed and high load, by providing a high-speed fan assembly in the input cavity, the flow rate of the air-fuel mixture can be effectively increased, ensuring that the gas in the crankcase can be quickly discharged, avoiding pressure accumulation. The high-speed fan assembly can significantly improve the ventilation efficiency of the PCV valve, thereby improving the performance and emission control effect of the engine, and forcing the exhaust gas in the crankcase to be discharged into the intake pipe and enter the cylinder for combustion, avoiding problems such as unstable air flow, slow response speed of the valve core, and insufficient durability when the engine runs at high load or high speed; the setting of the valve core structure and the first elastic structure enables the PCV valve to maintain stable opening and closing actions under different working conditions, avoiding wear or failure caused by long-term work. At the same time, the setting of the second elastic structure further enhances the sealing performance and stability of the valve body, ensuring the reliable operation of the PCV valve in various environments.

[0007] Further, the valve core structure includes a cone barrel body with a diameter gradually increasing from top to bottom and a seat body provided at the bottom of the cone barrel body. The diameter of the top of the cone barrel body is D, and the diameter of the seat body is F.

[0008] Further, both the first elastic structure and the second elastic structure are tower spring structures. The small heads of the first elastic structure and the second elastic structure are both arranged facing the seat body. The small head diameter of the first elastic structure is G, the large head diameter of the first elastic structure is H, the small head diameter of the second elastic structure is I, and the large head diameter of the second elastic structure is J.

[0009] Further, the diameter of the first through hole is A, the diameter of the second through hole is B, and the diameter of the third through hole is C, where B < F, D < I ≤ C < J ≤ A ≤ G < F < H.

[0010] Further, seals are provided between the first housing and the second housing and the valve body.

[0011] Further, the output cavity is in the shape of a Laval nozzle.

[0012] Further, the high-speed fan assembly includes a drive structure, a wing plate structure for fixing the drive structure on the input cavity, a PCB structure connected to the side of the drive structure away from the valve body, a rotating shaft structure connected to the side of the drive structure facing the valve body, a speed control switch connected to the side of the PCB structure away from the rotating shaft structure, a pad structure provided on the rotating shaft structure, and a fan blade structure provided on the side of the pad structure away from the drive structure.

[0013] On the other hand, the present invention also provides a positive crankcase ventilation system for an internal combustion engine, including an intake pipe, an air filter connected to the intake end of the intake pipe, an engine crankcase connected to the outlet end of the intake pipe, a first outlet pipe connected to the engine crankcase, a second outlet pipe connected to the engine crankcase, the above-mentioned PCV valve connected to the second outlet pipe, and an ECU electrically connected to the speed control switch for controlling the speed control switch.

[0014] Further, a supercharger, an intercooler, and a throttle are further provided on the intake pipe. The supercharger, the intercooler, and the throttle are sequentially arranged between the air filter and the engine crankcase. A combustion chamber is further provided in the engine crankcase. The outlet end of the intake pipe and the inlet end of the first outlet pipe are both connected to the combustion chamber, and the outlet end of the first outlet pipe is connected to the supercharger.

[0015] Further, an oil-gas separator is further provided on the second outlet pipe. The oil-gas separator is arranged between the engine crankcase and the PCV valve. The outlet end of the second outlet pipe is connected to the intake pipe and the outlet end of the second outlet pipe is arranged between the air filter and the supercharger. A pressure sensor is further provided in the engine crankcase. The pressure sensor is electrically connected to the ECU. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a schematic diagram of the overall structure of the PCV valve in Embodiment 1 of the present invention; Figure 2 It is a framework schematic diagram of the positive crankcase ventilation system for an internal combustion engine in Embodiment 2 of the present invention; Figure 3 This is a schematic diagram of the overall structure of the PCV valve in the low-speed and low-load state of the engine in Embodiment 2 of the present invention: Figure 4 This is a schematic diagram of the overall structure of the PCV valve in the high-speed and high-load state of the engine in Embodiment 2 of the present invention; Description of main component symbols:

[0017] The following specific embodiments will further illustrate the present invention in conjunction with the above-mentioned drawings. Specific Embodiments

[0018] For ease of understanding of the present invention, the present invention will be described more comprehensively below with reference to the relevant drawings. Several embodiments of the present invention are shown in the drawings. However, the present invention can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, these embodiments are provided so that the disclosure of the present invention is thorough and complete.

[0019] It should be noted that when an element is referred to as being "fixed to" another element, it can be directly on the other element or there can also be an intermediate element. When an element is considered to be "connected" to another element, it can be directly connected to the other element or there may be an intermediate element at the same time. The terms "vertical", "horizontal", "first", "second" and similar expressions used herein are for illustrative purposes only.

[0020] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those of ordinary skill in the technical field to which the present invention belongs. The terms used herein in the specification of the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention. The term "and / or" used herein includes any and all combinations of one or more of the related listed items.

[0021] Embodiment 1 Please refer to Figure 1, the PCV valve 11 in Embodiment 1 of the present invention includes a valve body 12, a first sleeve structure 20 sleeved on the input end of the valve body 12, and a second sleeve structure 32 sleeved on the output end of the valve body 12. On the side of the valve body 12 facing the first sleeve structure 20, a first cavity 13 is provided. On the side of the valve body 12 facing the second sleeve structure 32, a second cavity 14 is provided. The first cavity 13 is communicated with the second cavity 14 through a first through hole 15. A valve core structure 16 and a first elastic structure 19 sleeved on the valve core structure 16 are provided in the first cavity 13. The first sleeve structure 20 includes a first housing 21 sleeved on the input end of the valve body 12, an input cavity 22 provided in the first housing 21, and a second through hole 23 that communicates the input cavity 22 with the inside of the first cavity 13. A high-speed fan assembly 24 for increasing the exhaust gas flow rate is provided in the input cavity 22. The second sleeve structure 32 includes a second housing 33 sleeved on the output end of the valve body 12, an output cavity 34 provided in the second housing 33, and a spacer structure 35 provided between the output cavity 34 and the second cavity 14. A third through hole 36 that communicates the output cavity 34 with the inside of the second cavity 14 is provided in the spacer structure 35. A second elastic structure 37 is provided on the side of the spacer structure 35 facing the second cavity 14.

[0022] Further, the valve core structure 16 includes a conical barrel 17 whose diameter gradually increases from top to bottom and a seat body 18 provided at the bottom of the conical barrel 17. The diameter of the top of the conical barrel 17 is D, and the diameter of the seat body 18 is F.

[0023] Further, both the first elastic structure 19 and the second elastic structure 37 are conical spring structures. The small heads of the first elastic structure 19 and the second elastic structure 37 are both arranged facing the seat body 18. The small head diameter of the first elastic structure 19 is G, the large head diameter of the first elastic structure 19 is H, the small head diameter of the second elastic structure 37 is I, and the large head diameter of the second elastic structure 37 is J.

[0024] Further, the diameter of the first through hole 15 is A, the diameter of the second through hole 23 is B, the diameter of the third through hole 36 is C, B < F, D < I ≤ C < J ≤ A ≤ G < F < H.

[0025] Further, seal members 38 are provided between both the first housing 21 and the second housing 33 and the valve body 12.

[0026] Further, the output cavity 34 is in the shape of a Laval nozzle.

[0027] It can be understood that by arranging the output cavity 34 in the shape of a Laval nozzle, the exhaust gas flow velocity can be increased.

[0028] Further, the high-speed fan assembly includes a drive structure 25, a wing plate structure 26 for fixing the drive structure 25 on the input cavity 22, a PCB structure 27 connected to the side of the drive structure 25 away from the valve body 12, a rotating shaft structure 28 connected to the side of the drive structure 25 facing the valve body 12, a speed regulating switch 29 connected to the side of the PCB structure 27 away from the rotating shaft structure 28. A cushion block structure 30 is arranged on the rotating shaft structure 28 and a fan blade structure 31 is arranged on the side of the cushion block structure 30 away from the drive structure 25.

[0029] It can be understood that the setting of the valve core structure 16 and the first elastic structure 19 enables the PCV valve 11 to maintain stable opening and closing actions under different working conditions, avoiding wear or failure caused by long-term operation. At the same time, the setting of the second elastic structure 37 further enhances the sealing performance and stability of the valve body, ensuring the reliable operation of the PCV valve 11 in various environments.

[0030] Embodiment 2 On the other hand, the present invention also proposes an internal combustion engine crankcase forced ventilation system, which includes an intake pipe 1, an air filter 2 connected to the intake end of the intake pipe 1, an engine crankcase 6 connected to the outlet end of the intake pipe 1, a first outlet pipe 7 connected to the engine crankcase 6, a second outlet pipe 8 connected to the engine crankcase 6, the PCV valve 11 connected to the second outlet pipe 8, and an ECU 10 electrically connected to the speed regulating switch 29 for controlling the speed regulating switch 29.

[0031] Further, a supercharger 3, an intercooler 4, and a throttle valve 5 are further arranged on the intake pipe 1. The supercharger 3, the intercooler 4, and the throttle valve 5 are arranged in sequence between the air filter 2 and the engine crankcase 6. A combustion chamber 61 is further arranged in the engine crankcase 6. The outlet end of the intake pipe 1 and the intake end of the first outlet pipe 7 are both connected to the combustion chamber 61. The outlet end of the first outlet pipe 7 is connected to the supercharger 3.

[0032] Further, an oil-gas separator 9 is further arranged on the second outlet pipe 8. The oil-gas separator 9 is arranged between the engine crankcase 6 and the PCV valve 11. The outlet end of the second outlet pipe 8 is connected to the intake pipe 1 and the outlet end of the second outlet pipe 8 is arranged between the air filter 2 and the supercharger 3. A pressure sensor 62 is further arranged in the engine crankcase 6. The pressure sensor 62 is electrically connected to the ECU 10.

[0033] It is understandable that air entering the intake pipe 1 first passes through the air filter 2 to remove dust and impurities therein, ensuring that the air entering the engine crankcase 6 is clean; the air cleaned by the air filter 2 then enters the supercharger 3, where the air is compressed to increase its density and pressure to improve the efficiency and power output of the engine crankcase 6; the air compressed by the supercharger 3 is cooled by the intercooler 4, and the density of the cooled air further increases, which helps to improve the combustion efficiency; after the air is cooled by the intercooler 4, the throttle valve 5 controls the amount of air entering the engine crankcase 6 to adjust the air flow according to the driving demand; the air finally enters the combustion chamber 61, mixes with fuel and is ignited to generate power to drive the piston to move; part of the exhaust gas generated during the combustion process is processed by the oil-gas separator 9 and the PCV valve 11 and recycled to the supercharger 3 for repeated use to reduce emissions and recover part of the oil and gas.

[0034] Please refer to Figures 3 - 4 , the internal pressure of the engine crankcase 6 is monitored by the ECU 10. When the engine crankcase 6 is in a low-speed and low-load state, the internal pressure is less than -2 kPa, the vacuum degree of the intake pipe 1 is relatively large, far less than the pressure in the engine crankcase 6 at this time. The valve core structure 16 is sucked towards the second cavity 14 due to the pressure difference formed between the intake pipe 1 and the engine crankcase 6. The gap between the valve core structure 16 and the first through hole 15 is very small at this time, and the amount of cylinder leakage mixture passing through is very small. This is because in the idle or deceleration working conditions, the intake air volume and fuel volume required by the engine crankcase 6 are both small, and the amount of cylinder leakage gas generated by combustion is also relatively small. A smaller opening can meet the ventilation requirements of the engine crankcase 6, and at the same time ensure the normal operation and emission performance of the engine.

[0035] The internal pressure of the engine crankcase 6 is monitored by the ECU 10. When the engine crankcase 6 is in a medium-speed and medium-load state, the internal pressure is between -2 kPa and 0 kPa, and the vacuum degree of the intake pipe 1 is normal. At this time, the valve core structure 16 is closer to the second through hole 23 than in the low-speed and low-load state, and the gap between the valve core structure 16 and the first through hole 15 is wider than in the low-speed and low-load state, so that an appropriate amount of cylinder leakage mixture is sucked from the engine crankcase 6 into the intake pipe 1 and enters the combustion chamber 61 to participate in combustion. In this way, the unburned components in the cylinder leakage mixture can be effectively utilized to improve fuel economy, and at the same time, the pressure balance in the engine crankcase 6 can be maintained to prevent problems such as oil leakage caused by excessive pressure.

[0036] When the engine crankcase 6 is in a low-speed and low-load state or a medium-speed and medium-load state, the drive structure 25 can be driven, and the speed control switch 29 can be controlled by the ECU 10 to adjust the speed of the drive structure 25 to 15,000 r / min, so that the rotating shaft structure 28 drives the fan blade structure 31 to rotate counterclockwise, which can effectively increase the flow rate of the air-fuel mixture, and enable a small amount of cylinder leakage mixture to be sucked into the intake pipe 1 from the engine crankcase 6 faster and enter the combustion chamber 61 to participate in combustion.

[0037] The internal pressure of the engine crankcase 6 is monitored by the ECU 10. When the engine crankcase 6 is accelerating, the internal pressure is between 0 kPa and 2 kPa. The engine crankcase 6 requires a large amount of air and fuel to output greater power. The vacuum degree of the intake pipe 1 is relatively small. The valve core structure 16 is fully opened, and the vacuum channel of the valve core structure 16 is also fully opened, allowing more cylinder leakage mixture to enter the intake pipe 1. At the same time, a large amount of blow-by gas in the engine crankcase 6 is discharged to maintain the normal pressure in the engine crankcase 6. At this time, the drive structure 25 can be driven, and the speed control switch 29 can be controlled by the ECU 10 to adjust the speed of the drive structure 25 to 50,000 r / min, so that the rotating shaft structure 28 drives the fan blade structure 31 to rotate counterclockwise, which can effectively increase the flow rate of the air-fuel mixture, and enable more cylinder leakage mixture to be sucked into the intake pipe 1 from the engine crankcase 6 faster and enter the combustion chamber 61 to participate in combustion.

[0038] The internal pressure of the engine crankcase 6 is monitored by the ECU 10. When the engine crankcase 6 is operating at high speed and high load, the internal pressure is greater than 2 kPa. The valve core structure 16 is fully opened, and the vacuum channel of the valve core structure 16 is also fully opened, still not meeting the requirements. At this time, the drive structure 25 is driven, and the speed control switch 29 is controlled by the ECU 10 to adjust the speed of the drive structure 25 to 100,000 r / min, so that the rotating shaft structure 28 drives the fan blade structure 31 to rotate counterclockwise at high speed, which can effectively increase the flow rate of the air-fuel mixture, ensure that the gas in the engine crankcase 6 can be quickly discharged, avoid pressure accumulation, significantly improve the ventilation efficiency of the PCV valve 11, thereby improving the performance and emission control effect of the engine crankcase 6, and forcing the exhaust gas in the engine crankcase 6 to be discharged into the intake pipe 1 and enter the cylinder for combustion, avoiding problems such as unstable air flow, slow spool response speed, and insufficient durability when the engine crankcase 6 is operating at high load or high speed.

[0039] In summary, for the PCV valve and the positive crankcase ventilation system of an internal combustion engine containing the PCV valve in the above embodiments of the present invention, when the engine is running at high speed and high load, by arranging a high-speed fan assembly in the input cavity, the flow rate of the oil-gas mixture can be effectively increased, ensuring that the gas in the crankcase can be quickly discharged, avoiding pressure accumulation. The high-speed fan assembly can significantly improve the ventilation efficiency of the PCV valve, thereby improving the performance and emission control effect of the engine, and forcing the exhaust gas in the crankcase to be discharged into the intake pipe and enter the cylinder for combustion, avoiding problems such as unstable air flow, slow spool response speed, and insufficient durability when the engine is running at high load or high speed; the setting of the spool structure and the first elastic structure enables the PCV valve to maintain stable opening and closing actions under different working conditions, avoiding wear or failure caused by long-term operation. At the same time, the setting of the second elastic structure further enhances the sealing performance and stability of the valve body, ensuring the reliable operation of the PCV valve in various environments.

[0040] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples", etc. means that the specific features, structures, materials, or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described can be combined in a suitable manner in any one or more embodiments or examples.

[0041] The above-described embodiments merely represent several implementation manners of the present invention, and their descriptions are relatively specific and detailed, but should not be construed as limiting the scope of the invention patent of the present invention. It should be noted that for those of ordinary skill in the art, without departing from the concept of the present invention, several modifications and improvements can still be made, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the invention patent of the present invention shall be subject to the appended claims.

Claims

1. A PCV valve, characterized in that: The invention comprises a valve body, a first sleeve structure sleeved on the input end of the valve body, and a second sleeve structure sleeved on the output end of the valve body, a first cavity is arranged on the side of the valve body facing the first sleeve structure, a second cavity is arranged on the side of the valve body facing the second sleeve structure, the first cavity is communicated with the second cavity through a first through hole, a valve core structure and a first elastic structure sleeved on the valve core structure are arranged in the first cavity, the first sleeve structure comprises a first shell sleeved on the input end of the valve body, an input cavity arranged in the first shell, and a second through hole connecting the input cavity with the inside of the first cavity, a high-speed fan assembly for increasing the flow speed of exhaust gas is arranged in the input cavity, the second sleeve structure comprises a second shell sleeved on the output end of the valve body, an output cavity arranged in the second shell, and a pad structure arranged between the output cavity and the second cavity, a third through hole connecting the output cavity with the inside of the second cavity is opened on the pad structure, and a second elastic structure is arranged on the side of the pad structure facing the second cavity.

2. The PCV valve according to claim 1, characterized in that: The valve core structure includes a conical barrel body whose diameter gradually increases from top to bottom and a seat body arranged at the bottom of the conical barrel body. The diameter of the top of the conical barrel body is D, and the diameter of the seat body is F.

3. The PCV valve according to claim 2, characterized in that: The first elastic structure and the second elastic structure are both pagoda spring structures, and the small heads of the first elastic structure and the second elastic structure are both arranged toward the seat body. The diameter of the small head of the first elastic structure is G, the diameter of the large head of the first elastic structure is H, the diameter of the small head of the second elastic structure is I, and the diameter of the large head of the second elastic structure is J.

4. The PCV valve according to claim 3, characterized in that: The diameter of the first through hole is A, the diameter of the second through hole is B, and the diameter of the third through hole is C, B<F, D<I≤C<J≤A≤G<F<H.

5. The PCV valve according to claim 1, characterized in that: A sealing member is disposed between the first shell, the second shell and the valve body.

6. The PCV valve according to claim 1, characterized in that: The output cavity is in the shape of a Laval nozzle.

7. The PCV valve according to claim 1, characterized in that: The high-speed fan assembly includes a driving structure, a wing plate structure for fixing the driving structure on the input cavity, a PCB structure connected to the driving structure on a side away from the valve body, a rotating shaft structure connected to the driving structure on a side facing the valve body, and a speed regulating switch connected to the PCB structure on a side away from the rotating shaft structure; a pad structure is provided on the rotating shaft structure, and a fan blade structure is provided on the pad structure on a side away from the driving structure.

8. A crankcase forced ventilation system for an internal combustion engine, characterized in that: It includes an intake pipe, an air filter connected to the intake end of the intake pipe, an engine crankcase connected to the outlet end of the intake pipe, a first outlet pipe connected to the engine crankcase, a second outlet pipe connected to the engine crankcase, a PCV valve as described in any one of claims 1 to 7 connected to the second outlet pipe, and an ECU electrically connected to a speed control switch for controlling the speed control switch.

9. The internal combustion engine crankcase positive ventilation system according to claim 8, characterized in that: A supercharger, an intercooler and a throttle are also provided on the intake pipe. The supercharger, the intercooler and the throttle are sequentially provided between the air filter and the engine crankcase. A combustion chamber is also provided in the engine crankcase. The outlet end of the intake pipe and the inlet end of the first outlet pipe are both connected to the combustion chamber. The outlet end of the first outlet pipe is connected to the supercharger.

10. The internal combustion engine crankcase positive ventilation system according to claim 9, characterized in that: An oil-gas separator is also provided on the second air outlet pipe, and the oil-gas separator is arranged between the engine crankcase and the PCV valve. The outlet end of the second air outlet pipe is connected to the intake pipe and the outlet end of the second air outlet pipe is arranged between the air filter and the supercharger. A pressure sensor is also provided in the engine crankcase, and the pressure sensor is electrically connected to the ECU.

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