A sealing structure for the inlet cap of a urea injection assembly

Abstract

This utility model relates to the field of urea injectors, specifically disclosing a liquid inlet cap sealing structure for a urea injection assembly, including: a water jacket assembly, a valve body, a liquid inlet cap, and a sealing part. The valve body is composed of a wiring part, a coil part, and a liquid inlet pipe. The sealing part can be either a sealant with an integral filling structure or a component consisting of a first sealing ring and a second sealing ring for sealing. After sealing, it can prevent cooling water or external immersion water from seeping into the gaps between the wiring part and the liquid inlet pipe, as well as the gaps between the wiring part and the coil part, thus preventing water from entering and damaging the coil part and wiring part, thereby extending the service life of the valve body and reducing the failure rate.

Description

Technical Field

[0001] This utility model belongs to the field of urea injectors, and specifically relates to a liquid inlet cap sealing structure for a urea injection assembly. Background Technology

[0002] Urea injection assemblies are a common device in diesel engine exhaust aftertreatment systems. They mainly consist of a water jacket and an injection valve body. The injection valve body mainly consists of a wiring section with a plug, a coil section, an inlet pipe, and an injection pipe. In traditional urea injection assemblies, the water jacket usually only surrounds the lower part of the injection pipe and the coil section. However, in order to meet higher emission standards, the injection valve body needs to have better heat dissipation performance. Existing urea injection assemblies are designed with an extended overall length of the water jacket, so that its upper end is not lower than the upper end of the coil section, and it is assembled with the injection valve body through an inlet cap. This water jacket structure can effectively prevent the performance and life of the injection valve body from being affected by overheating of the coil (such as the urea metering valve assembly disclosed in patent document with application number "CN2022115013066").

[0003] However, the improved urea injection assembly, due to the excessively high position of the water jacket, is prone to condensation inside the inlet cap under high-temperature operating conditions. Furthermore, due to rain or external water intrusion during use, water can seep into the inlet cap through the clearance hole corresponding to the connector of the inlet cap and wiring section. This water can then seep into both ends of the wiring section. Since the wiring section's outer shell is typically made of plastic, while the coil and inlet pipe are made of metal, their expansion rates differ when heated. This increases the gap between the wiring section and the coil and inlet pipe, allowing condensation from the inlet cap or external water to seep into the coil or wiring section. This can lead to serious malfunctions and accidents such as short circuits in the coil and wiring section, thus affecting the service life of the injection valve body.

[0004] The above background information is provided only to assist in understanding the utility model concept and technical solution of this utility model, and it does not necessarily belong to the prior art of this patent application. In the absence of clear evidence that the above information was disclosed on the filing date of this patent application, the above background information should not be used to evaluate the novelty and inventiveness of this application. Utility Model Content

[0005] The purpose of this utility model is to provide a sealing structure for the inlet cap of a urea injection assembly, thereby overcoming the defect that water in the inlet cap of the existing water jacket extended urea injection assembly can easily seep into the coil and wiring parts from the gaps at both ends of the wiring part, which can easily cause short circuits and affect the life of the injection valve body.

[0006] To achieve the above objectives, this utility model provides a liquid inlet cap sealing structure for a urea injection assembly, comprising: a water jacket assembly, a valve body, and a liquid inlet cap. The valve body includes a wiring portion, which has a first end and a second end. The first end and the second end are respectively sleeved with a liquid inlet pipe and a coil portion. The water jacket assembly is sleeved on the outer periphery of the valve body and can surround the coil portion. The liquid inlet cap is covered on the outer periphery of the wiring portion and has a clearance hole. A sealing portion is provided on the outer periphery of the wiring portion, which can prevent water from seeping from the clearance hole to both ends of the wiring portion.

[0007] Preferably, in the above technical solution, the contour of the sealing part matches the area between the wiring part and the inner sidewall of the liquid inlet cap and fills that area.

[0008] Preferably, in the above technical solution, the sealing part includes a first sealing ring and a second sealing ring, the first sealing ring is closer to the first end, and the second sealing ring is closer to the second end.

[0009] Preferably, in the above technical solution, a first sealing groove is provided on the outer side of the first end, and the first sealing ring is stuck in the first sealing groove.

[0010] Preferably, in the above technical solution, the first sealing groove is provided with a first conical surface at one end near the second end, and the inner side of the liquid inlet cap is provided with a second conical surface. The second conical surface corresponds to the position of the first conical surface, and the first sealing ring is located between the first conical surface and the second conical surface. When the liquid inlet cap moves toward the water jacket assembly, the first conical surface and the second conical surface can squeeze the first sealing ring to generate deformation.

[0011] Preferably, in the above technical solution, the top of the water jacket assembly is provided with a top surface, and the inner side of the water jacket assembly and the coil part that are assembled together are provided with an inwardly recessed second sealing groove, the top of the second sealing groove being connected to the top surface.

[0012] Preferably, in the above technical solution, the outer side of the second sealing ring is provided with an outwardly protruding first sealing ring and a second sealing ring, the diameter of the first sealing ring is larger than the diameter of the second sealing ring, the first sealing ring abuts against the junction of the top surface and the second sealing groove, and the outer periphery of the second sealing ring abuts against the side of the second sealing groove; the top of the second sealing ring is provided with a clearance groove, the width of the clearance groove is consistent with the width of the clearance hole.

[0013] Preferably, in the above technical solution, the inner side of the liquid inlet cap is provided with a third conical surface, and the top of the second sealing ring is provided with a fourth conical surface. The third conical surface and the fourth conical surface abut against each other and cause the second sealing ring to deform.

[0014] Preferably, in the above technical solution, the outer periphery of the wiring part is provided with a first shoulder shaft, the diameter of the first shoulder shaft is consistent with the diameter of the second sealing groove and can be inserted into the second sealing groove, and the second sealing ring is located between the first shoulder shaft and the bottom of the second sealing groove.

[0015] Preferably, in the above technical solution, the outer periphery of the wiring part is provided with a second shoulder shaft, the diameter of the second shoulder shaft is larger than the diameter of the second sealing groove, the outer periphery of the second shoulder shaft extends outward from the side of the wiring part, the inner side of the liquid inlet cap is provided with a push surface, the push surface abuts against the top of the second shoulder shaft, and the second sealing ring is located between the bottom of the second shoulder shaft and the top surface.

[0016] Compared with existing technologies, this utility model has the following beneficial effects:

[0017] 1. The urea injection assembly of this utility model has a sealing structure for the inlet cap, which has a sealing part between the inlet cap and the coil part. The sealing part can be either a sealant for an integral filling structure or a component consisting of a first sealing ring and a second sealing ring. After sealing, it can prevent cooling water or external immersion water from seeping into the gaps between the wiring part and the inlet pipe, as well as the gaps between the wiring part and the coil part, thus preventing water from entering and damaging the coil part and the wiring part, thereby extending the service life of the valve body and reducing the failure rate.

[0018] 2. In this utility model, the first sealing groove near the second end can adopt a first conical surface design, and a second conical surface is provided on the inner side of the liquid inlet cap. When the liquid inlet cap is installed, the first and second conical surfaces can squeeze the first sealing ring due to the relative displacement, so that it can deform and seal in both longitudinal and transverse directions, thus improving the sealing effect.

[0019] 3. The second sealing ring in this utility model can adopt an irregular structure, with a first sealing ring and a second sealing ring protruding outward on its side. The diameter of the first sealing ring is larger than that of the second sealing ring. A fourth conical surface and a clearance groove are provided on the top of the second sealing ring. The clearance groove can make way for the wiring plug of the wiring part. A third conical surface is provided on the inside of the liquid inlet cap. When the liquid inlet cap is installed, the third conical surface can push the fourth conical surface to press down the second sealing ring. The first sealing ring and the second sealing ring can simultaneously seal the top surface and the second sealing groove, that is, simultaneously achieve longitudinal and transverse sealing, thereby improving the sealing effect.

[0020] 4. The wiring part of this utility model is provided with a first shoulder shaft or a second shoulder shaft on its outer periphery. The first shoulder shaft can press the second sealing ring into the bottom of the second sealing groove for sealing. When the liquid inlet cap is installed, the push surface inside the liquid inlet cap can push the top of the second shoulder shaft downward, thereby pressing the second sealing ring between the top surfaces to form an end face seal. Both the first and second shoulder shafts can provide longitudinal pressure to achieve longitudinal sealing. This method has a good sealing effect, high stability, and a simpler and more practical structure. Attached Figure Description

[0021] Figure 1 This is a structural diagram of existing technology.

[0022] Figure 2 This is a cross-sectional view of the liquid inlet cap sealing structure of the urea injection assembly in Example 1.

[0023] Figure 3 This is a structural diagram of the second sealing ring in Example 1.

[0024] Figure 4 This is a cross-sectional view of the liquid inlet cap sealing structure of the urea injection assembly in Example 2.

[0025] Figure 5 This is a cross-sectional view of the liquid inlet cap sealing structure of the urea injection assembly in Example 3.

[0026] Explanation of key figure labels:

[0027] 100 - Water jacket assembly, 110 - Top surface, 120 - Second sealing groove;

[0028] 200-Valve body, 210-Connecting part, 211-First shoulder shaft, 212-Second shoulder shaft, 220-First end, 230-Second end, 240-Inlet pipe, 250-Coil part, 260-First sealing groove, 261-First conical surface;

[0029] 300 - Liquid inlet cap, 310 - Displacement hole, 320 - Second conical surface, 330 - Third conical surface, 340 - Push surface;

[0030] 400 - Sealing part, 410 - First sealing ring, 420 - Second sealing ring, 421 - First sealing ring, 422 - Second sealing ring, 423 - Relief groove, 424 - Fourth conical surface. Detailed Implementation

[0031] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0032] In the description of this utility model, it should be noted that the terms "center", "longitudinal", "lateral", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "top surface", "bottom surface", "inner", "outer", "inner side", "outer side", etc., indicating the orientation or positional relationship are based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this utility model and simplifying the description, and are not intended to 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 utility model.

[0033] In the description of this invention, "several" means one or more, "multiple" means two or more, "greater than," "less than," and "exceeding" are understood to exclude the stated number, while "above," "below," and "within" are understood to include the stated number. Where the terms "first," "second," and "third" are used for descriptive purposes and to distinguish technical features, they should not be construed as indicating or implying relative importance, or implicitly indicating the number of indicated technical features, or implicitly indicating the sequential relationship of the indicated technical features.

[0034] In the description of this utility model, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "setting" 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 utility model based on the specific circumstances. The embodiments of this utility model will now be described based on its overall structure. Example 1

[0035] like Figure 2 and Figure 3As shown, the urea injection assembly in this embodiment includes the following sealing structure for the inlet cap: a water jacket assembly 100, a top surface 110, a second sealing groove 120, a valve body 200, a wiring part 210, a first end 220, a second end 230, an inlet pipe 240, a coil part 250, a first sealing groove 260, a first conical surface 261, an inlet cap 300, a clearance hole 310, a second conical surface 320, a third conical surface 330, a sealing part 400, a first sealing ring 410, a second sealing ring 420, a first sealing ring 421, a second sealing ring 422, a clearance groove 423, and a fourth conical surface 424.

[0036] The valve body 200 includes a wiring portion 210. A wiring plug extending outward is provided on one side of the wiring portion 210. The wiring portion 210 has a first end 220 and a second end 230 opposite to each other. The first end 220 and the second end 230 are respectively sleeved on the outside of the liquid inlet pipe 240 and the coil portion 250. The water jacket assembly 100 is sleeved on the outer periphery of the valve body 200 and the top of the water jacket assembly 100 can surround the coil portion 250. The liquid inlet cap 300 covers the outer periphery of the wiring portion 210. A clearance hole 310 is provided in the circumference of the liquid inlet cap 300. The bottom of the liquid inlet cap 300 is fixedly connected to the top of the water jacket assembly 100. The wiring plug can extend outward of the liquid inlet cap 300 through the clearance hole 310.

[0037] The sealing part 400 can also be composed of a split first sealing ring 410 and a second sealing ring 420. The first sealing ring 410 and the second sealing ring 420 are fitted around the outer periphery of the wiring part 210, with the first sealing ring 410 approaching the first end 220 and the second sealing ring 420 approaching the second end 230.

[0038] More specifically, a first sealing groove 260 is provided on the outer side of the first end 220, and a first sealing ring 410 is fitted into the first sealing groove 260; a top surface 110 is provided on the top of the water jacket assembly 100, and an inwardly recessed second sealing groove 120 is provided on the inner side of the water jacket assembly 100 and the coil part 250 where they are assembled; the top of the second sealing groove 120 is connected to the top surface 110 and forms a rounded corner structure at the junction; a first sealing ring 421 and a second sealing ring 422 protrude outwardly on the outer side of the second sealing ring 420, the diameter of the first sealing ring 421 is larger than the diameter of the second sealing ring 422, the first sealing ring 421 abuts against the rounded corner structure at the junction of the top surface 110 and the second sealing groove 120, and the outer periphery of the second sealing ring 422 abuts against the side of the second sealing groove 120; a clearance groove 423 is provided on the top of the second sealing ring 420, and the width of the clearance groove 423 is consistent with the width of the clearance hole 310.

[0039] Additionally, the first sealing groove 260 has a first conical surface 261 near the second end 230, and the inner side of the liquid inlet cap 300 has a second conical surface 320, which corresponds to the position of the first conical surface 261. The first sealing ring 410 is located between the first conical surface 261 and the second conical surface 320. A third conical surface 330 is also provided on the inner side of the liquid inlet cap 300, and the edges of the third conical surface 330 and the second conical surface 320 are connected to each other. The top of the second sealing ring 420 has a first conical surface 261. When the liquid inlet cap 300 moves toward the water jacket assembly 100 and assembles with it, the first cone surface 261 and the second cone surface 320 can squeeze the first sealing ring 410 to deform. The third cone surface 330 and the fourth cone surface 424 abut against each other and deform the second sealing ring 420. This causes the first sealing ring 421 to be squeezed toward the rounded corner structure at the junction of the top surface 110 and the second sealing groove 120, and the second sealing ring 422 to be squeezed toward the side of the second sealing groove 120. Example 2

[0040] like Figure 4 As shown, compared with Embodiment 1, the liquid inlet cap sealing structure of the urea injection assembly in this embodiment has a rectangular cross-section of the first sealing groove 260 and no first conical surface 261. Correspondingly, there is no second conical surface 320 inside the liquid inlet cap 300. The first sealing ring 410 is installed inside the first sealing ring 421 and abuts against the inner sidewall of the liquid inlet cap 300 and is squeezed and deformed.

[0041] In addition, in this embodiment, a first shoulder shaft 211 is provided on the outer periphery of the wiring part 210. The diameter of the first shoulder shaft 211 is consistent with the diameter of the second sealing groove 120 and can be inserted into the second sealing groove 120. The cross-section of the second sealing ring 420 is circular, and the second sealing ring 420 is located between the bottom of the first shoulder shaft 211 and the bottom of the second sealing groove 120. When the valve body 200 and the water jacket assembly 100 are installed together, the second sealing ring 420 can be deformed by the bottom surface of the first shoulder shaft 211 and the bottom of the second sealing groove 120, thereby achieving radial sealing between the valve body 200 and the water jacket assembly 100. Example 3

[0042] like Figure 5As shown, the difference between the urea injection assembly's inlet cap sealing structure in this embodiment and that in embodiment 2 is that a second shoulder shaft 212 is provided on the outer periphery of the wiring portion 210. The diameter of the second shoulder shaft 212 is larger than the diameter of the second sealing groove 120, and the outer periphery of the second shoulder shaft 212 extends outward from the side of the wiring portion 210. A third sealing groove is provided at the bottom of the second shoulder shaft 212, and a second sealing ring 420 is installed in the third sealing groove and located between the bottom and top surface 110 of the second shoulder shaft 212. A horizontal push surface 340 is provided on the inner side of the inlet cap 300. When the inlet cap 300 and the water jacket assembly 100 are installed together, the push surface 340 can abut against the top of the second shoulder shaft 212 and push it downward, causing the second sealing ring 420 to deform and thus seal the bottom and top surface 110 of the second shoulder shaft 212. Example 4

[0043] In addition to the above embodiments, the sealing part 400 can also fill the gap between the liquid inlet cap 300 and the wiring part 210 by injecting sealant into the liquid inlet cap 300 through the relief hole 310, so that the sealing part 400 forms an integral structure. The sealing part 400 can prevent water from seeping from the relief hole to both ends of the wiring part 210. However, the structure of the sealing part 400 in this embodiment has more comprehensive sealing performance than the split structure design in embodiments 1 to 3. However, there are problems such as the difficulty in avoiding the generation of air bubbles during the glue injection process, the difficulty of subsequent maintenance, the inability to completely remove the sealing part 400, and the difficulty of replacement.

[0044] In summary, the urea injection assembly in the above embodiments has a sealing part 400 between the inlet cap 300 and the coil part 250. The sealing part 400 can be a sealant of an integral filling structure or a component consisting of a first sealing ring 410 and a second sealing ring 420. After sealing, it can prevent cooling water or external immersion water from seeping into the gaps between the wiring part 210 and the inlet pipe 240 and between the wiring part 210 and the coil part 250, thus preventing water from entering and damaging the coil part 250 and the wiring part 210, thereby extending the service life of the valve body 200 and reducing the failure rate.

[0045] The foregoing description of specific exemplary embodiments of the present invention is for illustrative and explanatory purposes. These descriptions are not intended to limit the present invention to the precise forms disclosed, and it is obvious that many changes and variations can be made based on the above teachings. Although embodiments of the present invention have been shown and described, these specific embodiments are merely explanations of the present invention and are not intended to limit the invention. The specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. The purpose of selecting and describing exemplary embodiments is to explain the specific principles of the present invention and its practical application, so that those skilled in the art, after reading this specification, can make modifications, substitutions, variations, and various choices and changes to the embodiments as needed without departing from the principles and spirit of the present invention, provided that such modifications, substitutions, variations, and choices and changes are within the scope of the claims of the present invention and are protected by patent law.

Claims

1. A liquid inlet cap seal structure for a urea injection assembly, comprising: A water jacket assembly, a valve body, and an inlet cap are provided. The valve body includes a wiring portion with a first end and a second end, which are respectively connected to an inlet pipe and a coil portion. The water jacket assembly is fitted around the outer periphery of the valve body and can enclose the coil portion. The inlet cap is provided around the outer periphery of the wiring portion and has a clearance hole. The wiring portion is characterized in that a sealing portion is provided around its outer periphery, which can prevent water from seeping from the clearance hole to both ends of the wiring portion.

2. The liquid inlet cap seal structure of a urea injection assembly according to claim 1, wherein, The contour of the sealing portion matches and fills the area between the wiring portion and the inner wall of the liquid inlet cap.

3. The liquid inlet cap seal structure of a urea injection assembly according to claim 1, wherein, The sealing part includes a first sealing ring and a second sealing ring, with the first sealing ring moving towards the first end and the second sealing ring moving towards the second end.

4. The inlet cap sealing structure of the urea injection assembly according to claim 3, characterized in that, A first sealing groove is provided on the outer side of the first end, and the first sealing ring is stuck in the first sealing groove.

5. The liquid inlet cap seal structure of a urea injection assembly according to claim 4, wherein, The first sealing groove has a first conical surface at one end near the second end, and the inner side of the liquid inlet cap has a second conical surface. The second conical surface is positioned opposite to the first conical surface. The first sealing ring is located between the first conical surface and the second conical surface. When the liquid inlet cap moves toward the water jacket assembly, the first conical surface and the second conical surface can squeeze the first sealing ring to produce deformation.

6. The liquid inlet cap seal structure of a urea injection assembly according to claim 3, wherein, The top of the water jacket assembly is provided with a top surface, and the inner side of the water jacket assembly and the coil part that are assembled together is provided with an inwardly recessed second sealing groove, the top of the second sealing groove being connected to the top surface.

7. The liquid inlet cap seal structure of a urea injection assembly according to claim 6, wherein The outer side of the second sealing ring is provided with an outwardly protruding first sealing ring and a second sealing ring. The diameter of the first sealing ring is larger than the diameter of the second sealing ring. The first sealing ring abuts against the junction of the top surface and the second sealing groove. The outer periphery of the second sealing ring abuts against the side of the second sealing groove. The top of the second sealing ring is provided with a clearance groove. The width of the clearance groove is consistent with the width of the clearance hole.

8. The liquid inlet cap seal structure of a urea injection assembly according to claim 7, wherein, The inner side of the liquid inlet cap is provided with a third conical surface, and the top of the second sealing ring is provided with a fourth conical surface. The third conical surface and the fourth conical surface abut against each other and cause the second sealing ring to deform.

9. The liquid inlet cap seal structure of a urea injection assembly according to claim 6, wherein, The outer periphery of the wiring part is provided with a first shoulder shaft, the diameter of the first shoulder shaft is consistent with the diameter of the second sealing groove and can be inserted into the second sealing groove, and the second sealing ring is located between the first shoulder shaft and the bottom of the second sealing groove.

10. The liquid inlet cap seal structure of a urea injection assembly according to claim 6, wherein, The outer periphery of the wiring part is provided with a second shoulder shaft, the diameter of the second shoulder shaft is larger than the diameter of the second sealing groove, the outer periphery of the second shoulder shaft extends outward from the side of the wiring part, the inner side of the liquid inlet cap is provided with a push surface, the push surface abuts against the top of the second shoulder shaft, and the second sealing ring is located between the bottom of the second shoulder shaft and the top surface.

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