Extended-range engine EGR (exhaust gas recirculation) valve and motor shaft lever protection device thereof

Abstract

The invention discloses a range-extended engine EGR valve and a motor shaft rod protection device thereof, and relates to the field of configuration of electric EGR valves of new energy range-extended internal combustion engines. The first protective cover is arranged at the valve block end of a motor shaft rod in a sleeving mode, a guide face is constructed on the side, facing the valve block, of the first protective cover, and a containing cavity with the open top face is constructed on the side, facing the motor shaft rod, of the first protective cover; the positioning end of the motor shaft rod is sleeved with the second protective cover, the first end of the second protective cover is in interference fit with the valve body mounting base, and the second end of the second protective cover extends into the containing cavity and is in sliding contact with the outer wall of the motor shaft rod in an attached mode; the problem that an existing electric EGR valve is coked and blocked is solved.

Description

Technical Field

[0001] This invention relates to the field of electric EGR valve configuration for internal combustion engines in new energy range extenders, specifically, to an EGR valve for a range extender engine and its motor shaft protection device. Background Technology

[0002] With the continuous promotion of new energy, range-extended technology has become a mainstream technology. The technology of dedicated internal combustion engines for range-extended vehicles is updated and iterated rapidly. At the same time, with the continuous upgrading of national vehicle exhaust emission regulations, emission limits are becoming more and more stringent. The latest emission regulations, "Limits and Measurement Methods for Pollutant Emissions from Light-Duty Vehicles (China VI) (GB18352.6-2016)," require internal combustion engines to meet emission regulations by implementing new technologies, methods, and processes. The emission requirements for nitrogen oxides are gradually becoming stricter.

[0003] Modifying the engine itself and adding an Exhaust Gas Recirculation (EGR) system is a common and primary measure for reducing nitrogen oxides (NOx) in diesel engines. Diesel engine exhaust gases are inert gases; mixing them with the intake air increases the heat capacity of the mixture, allowing it to absorb more heat energy, lowering the combustion temperature, and inhibiting NOx formation. The addition of exhaust gases also dilutes the oxygen content of the mixture, reducing combustion speed and temperature, further lowering NOx levels. However, without a series of catalytic converters and particulate filters, HC (hydrocarbons) and PM (particulate matter) particles are unavoidable in the EGR gas. Therefore, while cooling the EGR gas, these substances deposit on the inner surfaces of the EGR system, making contaminant deposition difficult to prevent. These deposits degrade the performance of the EGR system over time. The electric EGR valve is a key component of the EGR system. The opening degree of the electric EGR valve controls the amount of circulating exhaust gas. By introducing a portion of the engine exhaust gas into the EGR cooler for cooling, the cooled exhaust gas enters the engine intake manifold through the electric EGR valve and mixes with fresh air to form a mixture. The mixture then enters the combustion chamber to participate in the combustion of the internal combustion engine.

[0004] Engine exhaust contains a complex array of pollutants, including HC compounds, particulate matter, sulfides, and nitrogen oxides. When exhaust gas passes through the electric EGR valve, these pollutants adhere to the motor shaft. As the amount of deposits increases, after the internal combustion engine stops and settles for a period of time, the deposits cool and form coke. The coke is hard and does not fall off on its own. This can cause the motor shaft of the electric EGR valve to become stuck or jammed, leading to inaccurate or malfunctioning control of the electronic EGR valve. Consequently, the EGR system malfunctions, resulting in excessive exhaust emissions from the internal combustion engine.

[0005] Solving the problem of sticking is a common issue with EGR valves, especially ordinary ones. Because of engine exhaust pollutants in the operating environment, the problem of coking and sticking cannot be completely resolved. Current measures involve cleaning the electric EGR valve. This involves disassembling the electric EGR valve after the engine has run for a period of time and cleaning the valve body and motor shaft with special materials. For severe coking, grinding and removal of the valve may be necessary. Cleaning is generally performed during engine maintenance. Summary of the Invention

[0006] The purpose of this invention is to provide an EGR valve for a range-extender engine and a motor shaft protection device thereon, which solves the problem of coking and jamming in existing electric EGR valves.

[0007] To solve the above problems, the present invention employs the following technical means: A protective device for the EGR valve motor shaft of a range-extender engine, comprising: The first protective cover is fitted onto the valve plate end of the motor shaft, with a guide surface on the side facing the valve plate and a receiving cavity with an open top surface on the side facing the motor shaft. The second protective cover is fitted onto the positioning end of the motor shaft. The first end is interference-fitted with the valve body mounting seat, and the second end extends into the receiving cavity and slides in contact with the outer wall of the motor shaft.

[0008] Preferably, the first protective cover includes a first conical cover that is positioned and connected to the motor shaft. The top end of the first conical cover is coaxially connected to a first barrel cover, and the top end of the first barrel cover is coaxially connected to a second conical cover. The movement range of the second end of the second protective cover does not exceed the top end of the second conical cover.

[0009] Furthermore, the first cone cover includes a mounting portion connected to the motor shaft and a first conical portion disposed at the top of the mounting portion, wherein the inner and outer diameters of the first conical portion are increased synchronously from bottom to top.

[0010] Furthermore, the second conical cover includes a second conical portion connected to the first barrel cover and a horizontal ring plate coaxially disposed at the top of the second conical portion. The horizontal ring plate is connected to the second conical portion by a rounded chamfer, and the inner and outer diameters of the second conical portion are increased synchronously from bottom to top.

[0011] Furthermore, the inner and outer sides of the first cone cover, the first barrel cover, and the second cone cover respectively serve as the receiving cavity and the guiding surface.

[0012] Furthermore, the second protective cover includes a second barrel cover serving as the first end, and a third conical cover serving as the second end is coaxially provided at the lower end of the second barrel cover. The inner and outer diameters of the second conical cover gradually decrease from top to bottom, and the lower end of the second conical cover is slidably fitted against the outer wall of the motor shaft. The inner diameter of the second barrel cover is larger than the outer diameter of the motor shaft.

[0013] In addition, an EGR valve for a range extender engine includes a body with a motor shaft, the motor shaft passing through a valve body mounting seat, the side of the valve body mounting seat having a valve body exhaust gas outlet, the bottom surface of the valve body mounting seat having a valve body exhaust gas inlet, and the valve plate end of the motor shaft passing through the valve body exhaust gas inlet and used to control the opening and closing of the valve body exhaust gas inlet. The motor shaft is equipped with a range-extended engine EGR valve motor shaft protection device as described in any one of claims 1 to 6; The guide surface is positioned toward the exhaust gas outlet of the valve body.

[0014] Furthermore, a shaft positioning sleeve is provided inside the valve body mounting seat, and the motor shaft slides coaxially through the shaft positioning sleeve; The positioning sleeve of the shaft is interference-fitted with the positioning tube of the valve body mounting seat. The lower end of the positioning tube is coaxially connected to a sleeve with a reduced outer diameter. The first end of the second protective cover is sleeved on the outer wall of the sleeve. A buffer cavity with the same thickness as the sleeve is constructed between the second protective cover and the motor shaft.

[0015] The present invention has the following beneficial effects during use: Firstly, the protective device prevents exhaust gas from directly impacting the motor shaft, effectively avoiding the coking of HC and particulate matter at the motor shaft and preventing shaft jamming. It also prevents corrosion of the motor shaft by acidic substances in the exhaust gas, thus reducing its strength and causing breakage. Simultaneously, the first protective cover prevents the high-temperature exhaust gas from repeatedly impacting the motor shaft, reducing its fatigue durability and causing breakage. Furthermore, the guide surface of the first protective cover effectively guides airflow, preventing the airflow entering the EGR valve from directly impacting the valve body and reducing intake pressure loss. This protective structure guides the airflow smoothly out of the EGR valve. Moreover, the second protective cover, besides preventing direct contact between the motor valve stem and exhaust gas, also allows for continuous cleaning of the outer wall of the motor valve stem by its second end, eliminating the need for after-sales service to disassemble and clean the electronically controlled EGR valve, thus reducing engine after-sales service costs. Attached Figure Description

[0016] Figure 1This is a schematic diagram of the structure of the motor shaft protection device of the present invention.

[0017] Figure 2 This is a schematic diagram of the EGR valve structure of the range extender engine of the present invention.

[0018] Figure 3 This is a schematic diagram of the airflow direction structure of the EGR valve in the range-extended engine of the present invention.

[0019] Among them, 1-first protective cover, 2-motor shaft, 3-valve plate, 4-accommodating cavity, 5-second protective cover, 6-first cone cover, 7-first barrel cover, 8-second cone cover, 9-second barrel cover, 10-third cone cover, 11-valve body mounting seat, 12-valve body exhaust gas outlet, 13-valve body exhaust gas inlet, 14-shaft positioning sleeve, 15-positioning tube, 16-sleeve connecting pipe, 17-buffer cavity. Detailed Implementation

[0020] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. The components of the embodiments of the present invention described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0021] Therefore, the following detailed description of the embodiments of the invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the invention without inventive effort are within the scope of protection of the invention.

[0022] It should be noted that, unless otherwise specified, the embodiments and features described in this invention can be combined with each other.

[0023] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0024] In the description of this invention, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship commonly used when the product of this invention is in use, or the orientation or positional relationship commonly understood by those skilled in the art. They are only used for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this invention. In addition, the terms "first," "second," etc., are only used to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0025] In the description of this invention, it should also be noted that, unless otherwise explicitly specified and limited, the terms "set," "install," "connect," and "link" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0026] Please refer to Figures 1 to 3 As shown, a protective device for the EGR valve motor shaft of a range-extender engine includes: The first protective cover 1 is sleeved on the valve plate 3 end of the motor shaft 2, and has a guide surface on the side facing the valve plate 3, and a receiving cavity 4 with an open top surface on the side facing the motor shaft 2. The second protective cover 5 is fitted onto the positioning end of the motor shaft 2. The first end is interference-fitted with the valve body mounting seat, and the second end extends into the receiving cavity 4 and slides in contact with the outer wall of the motor shaft 2.

[0027] The first protective cover 1 includes a first conical cover 6 that is positioned and connected to the motor shaft 2. The top end of the first conical cover 6 is coaxially connected to a first barrel cover 7. The top end of the first barrel cover 7 is coaxially connected to a second conical cover 8. The movement range of the second end of the second protective cover 5 does not exceed the top end of the second conical cover 8.

[0028] Furthermore, by ensuring that the movement range of the second end of the second protective cover 5 does not exceed the top end of the second conical cover 8, when the motor shaft 2 is scraped and cleaned by the second protective cover 5 during movement, the debris generated by the scraping is ensured to fall into and be collected in the receiving cavity 4. The first protective cover 1 is used to block the airflow, preventing the flow of waste airflow from causing debris generated during the cleaning and scraping of the motor shaft 2 to flow with the airflow and affect subsequent processes. Moreover, during the scraping process of the second protective cover 5, carbonized impurities, grease, etc. accumulated on the motor shaft 2 can be cleaned, preventing coking and jamming at the contact point between the motor shaft 2 and the valve body mounting seat.

[0029] When the EGR valve opens valve plate 3, the exhaust gas flows through the EGR valve and directly impacts the first protective cover 1. After being reflected by the first protective cover 1, the exhaust gas flows out of the EGR valve. Impurities such as HC, PM particles, sulfides, and acidic substances carried by the exhaust gas cannot directly impact the motor shaft 2, thus avoiding the problem of coking and jamming on the motor shaft 2. This reduces the problem of coking and jamming in the EGR valve, slows down the aging rate of the EGR valve motor shaft 2, extends the service life of the EGR valve, and reduces the need for after-sales disassembly and cleaning of the electric EGR valve.

[0030] Specifically, to ensure that the guiding surface on the outer side of the first protective cover 1 can effectively guide the exhaust gas and minimize direct contact between the exhaust gas and the motor shaft 2, the first conical cover 6 includes a mounting part connected to the motor shaft 2 and a first conical part located at the top of the mounting part. The inner and outer diameters of the first conical part increase synchronously from bottom to top. Furthermore, the second conical cover 8 includes a second conical part connected to the first barrel cover 7 and a horizontal ring plate coaxially located at the top of the second conical part. The horizontal ring plate is connected to the second conical part via a chamfered arc. The inner and outer diameters of the second conical part increase synchronously from bottom to top.

[0031] The inner and outer sides of the first cone cover 6, the first barrel cover 7, and the second cone cover 8 respectively serve as the receiving cavity 4 and the guide surface.

[0032] The guide surface formed in this way can guide the direction of the exhaust gas flow through the EGR valve, preventing the exhaust gas from directly impacting the motor shaft 2, while reducing exhaust gas flow resistance and reducing pressure drop loss.

[0033] In addition, the second protective cover 5 includes a second barrel cover 9 as the first end, and a third cone cover 10 as the second end is coaxially provided at the lower end of the second barrel cover 9. The inner and outer diameters of the second cone cover 8 gradually decrease from top to bottom, and the lower end of the second cone cover 8 is slidably fitted to the outer wall of the motor shaft 2. The inner diameter of the second barrel cover 9 is larger than the outer diameter of the motor shaft 2.

[0034] In this way, by making the inner diameter of the second barrel cover 9 larger than the outer diameter of the motor shaft, only the lower end of the second conical cover 8 contacts the outer wall of the motor shaft 2. This avoids excessive wear between the second barrel cover 9 and the motor shaft 2.

[0035] In addition, in this embodiment, a range extender engine EGR valve includes a body with a motor shaft 2. The motor shaft 2 passes through a valve body mounting seat 11. The side of the valve body mounting seat 11 is provided with a valve body exhaust gas outlet 12. The bottom surface of the valve body mounting seat 11 is provided with a valve body exhaust gas inlet 13. The valve plate 3 end of the motor shaft 2 passes through the valve body exhaust gas inlet 13 and is used to control the opening and closing of the valve body exhaust gas inlet 13. The aforementioned protective device for the range-extender engine EGR valve motor shaft 2 is installed on the motor shaft 2; The guide surface is positioned toward the exhaust gas outlet 12 of the valve body.

[0036] Specifically, a shaft positioning sleeve 14 is provided inside the valve body mounting seat 11, and the motor shaft 2 is coaxially slidably passed through the shaft positioning sleeve 14; The shaft positioning sleeve 14 is fitted with a positioning tube 15 that is interference-connected to the valve body mounting seat 11. The lower end of the positioning tube 15 is coaxially connected to a sleeve tube 16 with a reduced outer diameter. The first end of the second protective cover 5 is sleeved on the outer wall of the sleeve tube 16. A buffer cavity 17 with the same thickness as the sleeve tube 16 is constructed between the second protective cover 5 and the motor shaft 2.

[0037] In this way, after the protective device is installed, the exhaust gas can be prevented from directly impacting the motor shaft 2, effectively avoiding the coking of exhaust gas pollutants HC and particulate matter at the motor shaft 2, which could cause the shaft to jam. In addition, it can also prevent the motor shaft 2 from being corroded by acidic substances in the exhaust gas, which could weaken the strength of the motor shaft 2 and cause it to break. At the same time, the first protective cover 1 can prevent the high-temperature exhaust gas from impacting the motor shaft 2 back and forth, which could reduce the fatigue durability of the shaft and cause it to break. Furthermore, combined with the guide surface of the first protective cover 1, the airflow direction can be effectively guided, preventing the airflow entering the EGR valve from directly hitting the valve body and reducing the intake pressure loss. This protective structure can guide the airflow to flow smoothly out of the EGR valve. Moreover, the second protective cover 5 can not only prevent the motor valve rod from directly contacting the exhaust gas, but also use the second end of the second protective cover 5 to continuously hang on the outer wall of the motor valve rod, cleaning the outer wall of the motor valve rod. This can save the work of disassembling and cleaning the electronically controlled EGR valve by after-sales service, reducing the after-sales service cost of the engine.

[0038] Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A protective device for the motor shaft of an EGR valve in a range-extended engine, characterized in that, include: The first protective cover (1) is sleeved on the valve plate (3) end of the motor shaft (2), with a guide surface on the side facing the valve plate (3) and a receiving cavity (4) with an open top surface on the side facing the motor shaft (2). The second protective cover (5) is fitted onto the positioning end of the motor shaft (2). The first end is interference-fitted with the valve body mounting seat, and the second end extends into the receiving cavity (4) and slides in contact with the outer wall of the motor shaft (2).

2. The protective device for the motor shaft (2) of the range extender engine EGR valve according to claim 1, characterized in that, The first protective cover (1) includes a first cone cover (6) that is positioned and connected to the motor shaft (2). The top end of the first cone cover (6) is coaxially connected to a first barrel cover (7). The top end of the first barrel cover (7) is coaxially connected to a second cone cover (8). The movement range of the second end of the second protective cover (5) does not exceed the top end of the second cone cover (8).

3. The protective device for the EGR valve motor shaft (2) of a range-extended engine according to claim 2, characterized in that, The first cone cover (6) includes a mounting part connected to the motor shaft (2) and a first cone-shaped part located at the top of the mounting part. The inner and outer diameters of the first cone-shaped part are increased synchronously from bottom to top.

4. The protective device for the EGR valve motor shaft (2) of a range-extended engine according to claim 2, characterized in that, The second cone cover (8) includes a second cone-shaped part connected to the first barrel cover (7) and a horizontal ring plate coaxially disposed at the top of the second cone-shaped part. The horizontal ring plate is connected to the second cone-shaped part by a rounded chamfer. The inner and outer diameters of the second cone-shaped part are increased synchronously from bottom to top.

5. A protective device for the EGR valve motor shaft (2) of a range-extended engine according to claim 2, characterized in that, The inner and outer sides of the first cone cover (6), the first barrel cover (7), and the second cone cover (8) serve as the receiving cavity (4) and the guide surface, respectively.

6. The protective device for the motor shaft (2) of the range extender engine EGR valve according to claim 1, characterized in that, The second protective cover (5) includes a second barrel cover (9) as the first end. The lower end of the second barrel cover (9) is coaxially provided with a third cone cover (10) as the second end. The inner and outer diameters of the second cone cover (8) gradually decrease from top to bottom. The lower end of the second cone cover (8) is slidably fitted to the outer wall of the motor shaft (2). The inner diameter of the second barrel cover (9) is larger than the outer diameter of the motor shaft (2).

7. An EGR valve for a range-extended engine, comprising a body having a motor shaft (2), characterized in that, The motor shaft (2) passes through the valve body mounting seat (11). The side of the valve body mounting seat (11) is provided with a valve body waste gas outlet (12), and the bottom surface of the valve body mounting seat (11) is provided with a valve body waste gas inlet (13). The valve plate (3) end of the motor shaft (2) passes through the valve body waste gas inlet (13) and is used to control the opening and closing of the valve body waste gas inlet (13). The motor shaft (2) is equipped with a protective device for the motor shaft (2) of the range-extended engine EGR valve as described in any one of claims 1 to 6; The guide surface is positioned toward the exhaust gas outlet (12) of the valve body.

8. The EGR valve for a range-extender engine according to claim 7, characterized in that, A shaft positioning sleeve (14) is provided inside the valve body mounting seat (11), and the motor shaft (2) slides coaxially through the shaft positioning sleeve (14); The shaft positioning sleeve (14) is fitted with a positioning tube (15) that is interference-connected to the valve body mounting seat (11). The lower end of the positioning tube (15) is coaxially connected to a sleeve tube (16) with a reduced outer diameter. The first end of the second protective cover (5) is fitted onto the outer wall of the sleeve tube (16). A buffer cavity (17) with the same thickness as the sleeve tube (16) is constructed between the second protective cover (5) and the motor shaft (2).

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