Valve element assembly and EGR valve

Abstract

The valve element assembly comprises a valve shaft and a shaft sleeve shell arranged outside the valve shaft in a sleeving mode, one end of the valve shaft extends out of a first port of the shaft sleeve shell and is used for being in transmission connection with a swing arm at a motor end, and the other end of the valve shaft extends out of a second port of the shaft sleeve shell and is provided with a valve plate; the valve element assembly further comprises a carbon scraping ring which is located in the shaft sleeve shell and arranged outside the valve shaft in a sleeving mode. The inner side face of the carbon scraping ring is of a non-planar structure, and the carbon scraping ring can make contact with the surface of the valve shaft and scrape carbon on the valve shaft in the moving process of the valve shaft. According to the valve element assembly and the EGR valve, due to the fact that the carbon scraping ring is arranged between the shaft sleeve shell and the valve shaft, carbon deposition on the surface of the valve shaft can be scraped through the carbon scraping ring, and normal operation of the EGR valve is guaranteed.

Description

Technical Field

[0001] The present application relates to the technical field of engine exhaust gas recirculation, and in particular to a valve core assembly and an EGR valve provided with the valve core assembly. Background Art

[0002] With the continuous improvement of the country's environmental protection requirements and the implementation of the National VI emission regulations for engines, the requirements for nitrogen oxides (NOx) in the exhaust gas emitted by the engine have become more stringent. The implementation of the EGR (abbreviation of Exhaust Gas Re-circulation) route can effectively reduce the emission of nitrogen oxides (NOx) in the engine exhaust gas, improve fuel economy, reduce knock, and extend the service life of the engine.

[0003] EGR routing involves recirculating some of the engine's exhaust gas back into the intake manifold. This exhaust gas contains corrosive gases and significant amounts of water vapor. This is particularly true for natural gas and methanol-fueled engines. Methanol, formic acid, and sulfides can corrode components, placing even higher demands on the EGR valve. Failure of the EGR valve can directly lead to substandard emissions, poor fuel economy, increased risk of knock, and reduced engine life.

[0004] Currently, cold-end EGR valves primarily utilize a poppet valve structure, with a clearance fit between the bushing and the valve shaft. During the exhaust gas recirculation process, soot particles (i.e., carbon deposits from engine combustion) in the exhaust gas can deposit on the valve shaft surface, causing valve shaft sticking and even leading to EGR valve failure and engine malfunction.

[0005] Therefore, how to reduce or even avoid the carbon deposition problem on the valve shaft surface to avoid EGR valve sticking and increase the service life of the EGR valve is a technical problem that needs to be solved urgently by those skilled in the art. Utility Model Content

[0006] In view of this, the purpose of the present application is to provide a valve core assembly suitable for an EGR valve and an EGR valve, which can solve the problem of carbon deposits on the valve shaft surface and avoid sticking, thereby increasing the service life of the EGR valve.

[0007] To achieve the above objectives, this application provides the following technical solutions:

[0008] A valve core assembly suitable for use in an EGR valve, the valve core assembly comprising a valve shaft and a shaft sleeve housing sleeved outside the valve shaft, one end of the valve shaft extending out of a first port of the shaft sleeve housing for transmission connection with a swing arm at a motor end, and the other end extending out of a second port of the shaft sleeve housing and provided with a valve plate;

[0009] The valve core assembly also includes a carbon scraper ring: the carbon scraper ring is located in the shaft sleeve shell and is sleeved outside the valve shaft; the inner side surface of the carbon scraper ring is a non-planar structure, which can contact the surface of the valve shaft and scrape carbon on it during the movement of the valve shaft.

[0010] Optionally, in the above valve core assembly, at least a partial annular area of the inner side surface of the carbon scraper ring includes a surface made of wire mesh.

[0011] Optionally, in the above valve core assembly, the carbon scraper ring includes a sleeve structure woven or wound by a wire mesh.

[0012] Optionally, in the above-mentioned valve core assembly, the wire mesh is made of stainless steel.

[0013] Optionally, in the above-mentioned valve core assembly, a limiting protrusion is provided in the second port of the shaft sleeve housing, for limiting the carbon scraper ring in the shaft sleeve housing.

[0014] Optionally, the valve core assembly further includes a getter ring:

[0015] The getter ring is sleeved outside the valve shaft and located inside the shaft sleeve housing, and a first through hole is provided on the side wall of the getter ring;

[0016] The side wall of the shaft sleeve housing is provided with a second through hole, and the second through hole is communicated with the first through hole.

[0017] Optionally, in the above-mentioned valve core assembly, an annular groove is provided on the side wall of the getter ring along the circumferential direction, and the first through hole is located in the annular groove.

[0018] Optionally, in the above valve core assembly, sealing devices are respectively provided on both sides of the getter ring.

[0019] Optionally, in the above valve core assembly, any one or more combinations of a sealing device, a bushing, and a positioning ring are further provided between the shaft sleeve shell and the valve shaft.

[0020] Optionally, in the above-mentioned valve core assembly, the shaft sleeve housing, the sealing device, the bushing, the positioning ring and the carbon scraping ring are all made of anti-corrosion materials.

[0021] An EGR valve comprises a motor, a motor base, a swing arm, and the valve core assembly described above, wherein: the valve shaft in the valve core assembly is transmission-connected to the drive shaft in the motor via the swing arm; and the shaft sleeve housing in the valve core assembly is fixedly connected to the motor base.

[0022] It can be seen from the above technical solution that in the EGR valve and its valve core assembly provided by the present application, a carbon scraper ring is provided between the shaft sleeve shell and the valve shaft, so that the carbon deposits on the surface of the valve shaft can be scraped off by the carbon scraper ring to ensure the normal operation of the EGR valve. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0024] Figure 1 A cross-sectional view of an EGR valve provided in an embodiment of the present application.

[0025] Figure 2 A schematic diagram of the airflow path of exhaust gas in an EGR valve provided in an embodiment of the present application.

[0026] Figure 3 A schematic diagram of the wire mesh winding structure in a carbon scraping ring provided in an embodiment of the present application.

[0027] Figure 4 A schematic structural diagram of a getter ring provided in an embodiment of the present application.

[0028] Figure 5 for Figure 4 Half-section of the getter ring.

[0029] Figure 6 A half-section view of a sealing ring provided in an embodiment of the present application.

[0030] in:

[0031] 1-motor, 2-motor seat, 3-hexagonal flange nut, 4-valve cover, 5-swing arm,

[0032] 6-Hexagonal nut, 7-Roller, 8-Pin, 9-Valve shaft, 10-Second locating ring,

[0033] 11-second bushing, 12-first sealing device, 13-first positioning ring, 14-shaft sleeve shell,

[0034] 15-second sealing ring, 16-first sealing ring, 17-second sealing device, 18-getter ring, 19-first bushing, 20-carbon scraper ring, 21-second valve disc, 22-valve body, 23-first valve disc. DETAILED DESCRIPTION

[0035] The present application provides a valve core assembly suitable for an EGR valve and an EGR valve, which can scrape and clean carbon deposits on the surface of the valve shaft through a carbon scraper ring, thereby solving the carbon deposit problem on the valve shaft surface, avoiding EGR valve sticking, and improving the service life of the EGR valve.

[0036] The following will be combined with the drawings in the embodiments of this application to clearly and completely describe the technical solutions in the embodiments of this application. Obviously, the embodiments described are only part of the embodiments of this application, not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of this application.

[0037] See Figure 1 The embodiment of the present application provides a valve core assembly suitable for an EGR valve. The valve core assembly includes a valve shaft 9, a shaft sleeve 14, and a carbon scraper ring 20. The shaft sleeve 14 is sleeved on the outside of the valve shaft 9, and one end of the valve shaft 9 extends out of the first port (i.e., Figure 1 and Figure 2 The left end of the shaft sleeve 14 is open) and is used for transmission connection with the swing arm 5 at the motor end. The other end of the valve shaft 9 extends out of the second port (i.e. Figure 1 and Figure 2 The right end of the middle shaft sleeve 14 is open) and a valve plate is provided outside; the carbon scraper ring 20 is located between the shaft sleeve 14 and the valve shaft 9, that is, the carbon scraper ring 20 is located inside the shaft sleeve 14 and is sleeved outside the valve shaft 9; moreover, the inner side surface of the carbon scraper ring 20 is a non-planar structure, which contacts the surface of the valve shaft 9, and can scrape and clean the carbon deposits on the surface of the valve shaft 9 during the movement of the valve shaft 9 relative to the carbon scraper ring 20, thereby ensuring the normal operation of the EGR valve.

[0038] In some embodiments, the carbon scraping ring 20 is a sleeve structure made of a wire mesh through weaving or winding or other similar methods. In order to prevent the exhaust gas from corroding the carbon scraping ring 20, the wire mesh is made of stainless steel. The winding structure can be seen in FIG. Figure 3 (For illustration only). However, it is not limited to this. In other embodiments, the carbon scraper ring 20 can also be designed as other structural forms. For example, a wire mesh structure is nested in the sleeve, so that at least part of the annular area on the inner side of the carbon scraper ring 20 includes a surface made of wire mesh, and the carbon deposits on the surface of the valve shaft 9 can be scraped and cleaned through the wire mesh structure. Specifically, the diameter of the stainless steel wire in the wire mesh can be any value in the range of 0.3mm to 1mm, such as 0.5mm. During the EGR valve process, since the wire mesh structure has the characteristics of multiple gaps and a certain degree of elasticity, the contact between it and the valve shaft 9 is similar to the contact between a point and a surface. Therefore, when the valve shaft 9 moves axially relative to the carbon scraper ring 20, the carbon scraper ring 20 with the wire mesh structure can scrape and clean the carbon deposits on the surface of the valve shaft 9.

[0039] In some embodiments, a limiting protrusion 141 is provided within the second port of the shaft sleeve housing 14 to retain the carbon scraper ring 20 within the shaft sleeve housing 14. Alternatively, in other embodiments, a limiting retaining ring (not shown) may be provided outside the second port of the shaft sleeve housing 14, connected to the shaft sleeve housing 14, and having an inner diameter smaller than the outer diameter of the carbon scraper ring 20, thereby retaining the carbon scraper ring 20 within the shaft sleeve housing 14. Furthermore, after the EGR valve has operated for a period of time, the limiting retaining ring can be removed from the shaft sleeve housing 14 to facilitate inspection and maintenance of the actual working condition of the carbon scraper ring 20.

[0040] like Figure 2 As shown, during the operation of the EGR valve, water vapor and corrosive gases in the exhaust gas can easily pass through the gap between the shaft sleeve 14 and the valve shaft 9 and enter the interior of the valve body and the area where the valve shaft 9 is connected to the motor 1, causing corrosion, sticking and motor failure inside the valve body and / or the above-mentioned connection area, affecting the working stability and service life of the EGR valve.

[0041] In view of this, a getter ring 18 is also provided in the valve core assembly. Figure 1 As shown, a getter ring 18 is sleeved over the valve shaft 9 and located within the shaft sleeve housing 14. It is provided with a first through hole 180, with both ends of the first through hole 180 opening on the inner and outer sides of the getter ring 18, respectively. Correspondingly, a second through hole 140 is provided on the sidewall of the shaft sleeve housing 14. One end of the second through hole 140 opens into communication with the first through hole 180, while the other end opens into communication with the atmosphere outside the shaft sleeve housing 14, located on the outer side of the shaft sleeve housing 14. Thus, exhaust gas that has entered the valve body can be discharged through the getter ring 18, preventing the exhaust gas from adversely affecting the interior of the valve body.

[0042] See Figure 4 and Figure 5 In a specific implementation, an annular groove 181 can be provided along the circumferential direction on the side wall of the getter ring 18, and the first through hole 180 is located in the annular groove 181. The annular groove 181 facilitates the communication between the first through hole 180 and the second through hole 140 on the shaft sleeve housing 14, which is beneficial for exhaust gas discharge.

[0043] In a specific implementation, only one first through hole 180 can be provided on the side wall of the getter ring 18, or two or more first through holes 180 can be provided along the circumferential direction of the side wall of the getter ring 18. Correspondingly, the second through hole 140 provided on the side wall of the shaft sleeve housing 14 can be one or more. In addition, the specific shapes of the first through hole 180 and the second through hole 140 can be circular, elliptical, or any other arbitrary shape. The present application does not impose any specific restrictions on the specific shape and number of the first through hole 180 and the second through hole 140, as long as the second through hole 140 can be connected to the first through hole 180 to discharge the exhaust gas.

[0044] Furthermore, in some embodiments, any one or more combinations of a sealing device, a bushing, and a positioning ring are further provided between the shaft sleeve housing 14 and the valve shaft 9. The bushing, positioning ring, and carbon scraper ring 20 may all be made of metal, preferably a corrosion-resistant material (e.g., stainless steel), and the sealing device may be made of fluororubber.

[0045] For specific implementation, please refer to Figure 1 The end of the valve shaft 9 away from the motor 1 can be provided with a first valve disc 23 and a second valve disc 21 side by side, or in other embodiments, only one valve disc can be provided according to actual needs. Moreover, the shaft sleeve housing 14 can be provided with multiple sealing devices, multiple bushings, and multiple positioning rings, or in other embodiments, only one sealing device, one bushing, and one positioning ring can be provided according to actual needs. For example, see Figure 1 The getter ring 18, located near the valve disc, has a first sealing device 12, a first bushing 19, a first positioning ring 13, a carbon scraper ring 20, and a stopper protrusion 141 arranged in this order. The getter ring 18, located near the motor 1 and the swing arm 5, has a second bushing 11, a second sealing device 17, and a second positioning ring 10 arranged in this order. The first sealing device 12 and the second sealing device 17 form a double-layer sealing structure, which prevents exhaust gas and moisture from entering the EGR valve cavity and causing failure.

[0046] In some embodiments, the first sealing device 12 and the second sealing device 17 are both made of a Y-shaped sealing ring made of an anti-corrosion material (such as fluororubber). The specific structure thereof can be found in Figure 6. The Y-type sealing ring has a self-sealing effect, which specifically means that the Y-type sealing ring relies on its open lip to stick to the coupling surface of the sealing pair. When there is no internal pressure, only a very small contact pressure is generated due to the deformation of the lip tip. In the case of sealing, there is a normal pressure equal to the medium pressure at each point in contact with the sealing medium, so the bottom of the lip ring will be compressed axially, and the lip will be compressed circumferentially, and the contact with the sealing surface will become wider, and the contact stress will increase. When the internal pressure rises again, the distribution form and size of the contact pressure will change further, and the lip will fit more closely with the sealing surface, so the sealing performance will be better. When installing the Y-type sealing ring, its Y-shaped opening direction is facing the airflow direction to make the sealing performance better through the airflow pressure.

[0047] In some embodiments, the above-mentioned bushing, positioning ring and carbon scraper ring 20 are all made of corrosion-resistant materials (such as 304 stainless steel). Therefore, even if the various parts in the above-mentioned valve core assembly are exposed to exhaust gas for a long time, the valve core assembly and the driving mechanism in the motor transmission connection area will not fail.

[0048] It can be seen that in the valve core assembly provided in the present application, the sealing device can prevent corrosive gases and water vapor from entering the interior of the EGR valve, reduce or even avoid corrosion problems inside the valve body and in the area where the valve shaft 9 is connected to the motor 1, thereby avoiding failure of the EGR valve, improving the stability of the EGR valve, and increasing the service life of the engine.

[0049] The present application also provides an EGR valve, such as Figure 1 As shown, the EGR valve includes a motor 1, a motor seat 2, a swing arm 5, and also includes a valve core assembly as described above, wherein the valve shaft 9 in the valve core assembly is connected to the drive shaft in the motor 1 through the swing arm 5, and the shaft sleeve shell 14 in the valve core assembly is fixedly connected to the motor seat 2.

[0050] In addition, if Figure 1As shown in the figure, the motor 1 is connected to the motor base 2 through the hexagonal flange nut 3, the swing arm 5 is fixed to the motor 1 shaft through the hexagonal nut 6, the swing arm 5 is connected to the roller 7 through the crescent groove, the roller 7 is connected to the valve shaft 9 through the pin 8, the valve body 22 is pressed into the motor base 2 through an interference fit, the shaft sleeve shell 14 is connected to the valve body 22 through an interference fit, the scraper ring 20 is installed in the shaft sleeve shell 14 through the valve shaft 9, the left end of the scraper ring 20 is pressed into the first locating ring 13, and the left end of the first locating ring 13 is connected to the first bushing 19 The left end of the first bushing 19 is the first sealing device 12, the left end of the first sealing device 12 is the getter ring 18, the left end of the getter ring 18 is the second bushing 11, the left end of the second bushing 11 is the second sealing device 17, and the left end of the second sealing device 17 is the second positioning ring 10. The above carbon scraping ring 20, first positioning ring 13, first bushing 19, first sealing device 12, getter ring 18, second bushing 11, second sealing device 17, and second positioning ring 10 are all sleeved on the valve shaft 9. The right end of the valve shaft 9 is connected to the first valve disc 23 and the second valve disc 21, and the valve body 22 is provided with a first sealing ring 16 and a second sealing ring 15.

[0051] The working process of the EGR valve includes:

[0052] The motor 1 is a torque motor. When it is powered on, it can drive the swing arm 5 to rotate through the motor shaft. At this time, the roller 7 controls the valve shaft 9 to move left and right through the crescent groove line on the swing arm 5 (in the actual product, the valve shaft 9 can move up and down. The left and right mentioned in this manual are both Figure 1 and Figure 2 (the direction in the middle is taken as the reference);

[0053] When the valve shaft 9 moves to the right, the first valve plate 23 and the second valve plate 21 connected to the valve shaft 9 move to the right, the EGR valve opens, and the exhaust gas flows into the engine through the gap between the valve plate and the valve body;

[0054] Because the first valve disc 23, the second valve disc 21 and the valve body 22 are all metal parts, they cannot be completely sealed. Moreover, when the EGR valve is opened, exhaust gas and water vapor will enter the shaft sleeve housing 14 through the gap between the second valve disc 21 and the valve body 22. At this time, because the first sealing device 12 and the second sealing device 17 form a double sealing structure, and all parts in the shaft sleeve housing 14 are made of corrosion-resistant materials, the risk of internal water ingress and internal corrosion can be avoided. Especially for gas engines and methanol engines with high moisture and corrosive gases, exhaust gas corrosion can be prevented from causing EGR valve failure and subsequent engine abnormalities.

[0055] When the engine combustion is incomplete, carbon deposits will exist, which will cause carbon deposits to accumulate on the valve shaft 9. At this time, the carbon scraper ring 20 can effectively remove the carbon deposits on the valve shaft 9 to ensure the stability of the EGR valve.

[0056] Finally, it should be noted that, in this document, relational terms such as first and second, etc., are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the terms "comprises," "comprising," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that includes a list of elements includes not only those elements but also other elements not explicitly listed.

[0057] The various embodiments in this specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the various embodiments can be referenced to each other.

[0058] The above description of the disclosed embodiments is intended to enable one skilled in the art to implement or use the present application. Various modifications to these embodiments will be readily apparent to one skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present application. Therefore, the present application is not limited to the embodiments shown herein, but is intended to conform to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A valve core assembly suitable for an EGR valve, the valve core assembly comprising a valve shaft (9) and a shaft sleeve (14) sleeved outside the valve shaft (9), one end of the valve shaft (9) extending out of a first port of the shaft sleeve (14) for transmission connection with a swing arm (5) at a motor end, and the other end extending out of a second port of the shaft sleeve (14) and provided with a valve plate; It is characterized in that Also includes a carbon scraping ring (20): The carbon scraping ring (20) is located in the shaft sleeve housing (14) and is sleeved outside the valve shaft (9); The inner side surface of the carbon scraping ring (20) is a non-planar structure, capable of contacting the surface of the valve shaft (9) and scraping carbon from the valve shaft (9) during its movement.

2. The valve core assembly according to claim 1, characterized in that: In the carbon scraping ring (20), at least a partial annular area of the inner side surface comprises a surface made of a wire mesh.

3. The valve core assembly according to claim 2, characterized in that: The carbon scraping ring (20) comprises a sleeve structure woven or wound from a wire mesh.

4. The valve core assembly according to any one of claims 2 or 3, characterized in that: The wire mesh is made of stainless steel.

5. The valve core assembly according to claim 1, characterized in that: A limiting protrusion (141) is provided in the second port of the shaft sleeve (14) for limiting the carbon scraping ring (20) in the shaft sleeve (14).

6. The valve core assembly according to claim 1, characterized in that Also included is a getter ring (18): The getter ring (18) is sleeved outside the valve shaft (9) and located inside the shaft sleeve housing (14), and a first through hole (180) is provided on a side wall of the getter ring (18); A second through hole (140) is provided on the side wall of the shaft sleeve housing (14), and the second through hole (140) is communicated with the first through hole (180).

7. The valve core assembly according to claim 6, characterized in that: An annular groove (181) is provided on the side wall of the getter ring (18) along the circumferential direction, and the first through hole (180) is located in the annular groove (181); And / or, sealing devices are respectively provided on both sides of the getter ring (18).

8. The valve core assembly according to claim 1, characterized in that Any one or more combinations of a sealing device, a bushing, and a positioning ring are also provided between the shaft sleeve shell (14) and the valve shaft (9).

9. The valve core assembly according to claim 8, characterized in that: The shaft sleeve housing (14), the sealing device, the bushing, the positioning ring and the carbon scraping ring (20) are all made of anti-corrosion materials.

10. An EGR valve, comprising a motor (1), a motor base (2), and a swing arm (5), characterized in that: Also includes a valve core assembly according to any one of claims 1 to 9, wherein: The valve shaft (9) in the valve core assembly is in transmission connection with the drive shaft in the motor (1) via the swing arm (5); The shaft sleeve housing (14) in the valve core assembly is fixedly connected to the motor seat (2).

Images