Urea sensor pipeline connecting structure

Abstract

The urea sensor pipeline connecting structure comprises a sensor end, a urea suction pipe and a urea suction connector, a first mounting hole penetrating through the bottom wall of the sensor end is formed in the sensor end, the top end of the urea suction pipe is inserted into the first mounting hole, one side of the first mounting hole is communicated with a second mounting hole, and the other side of the first mounting hole is communicated with the urea suction connector. And the urea suction joint is embedded into the second mounting hole. Through the structural design of the urea sensor pipeline, the urea suction pipeline is integrally combined by stainless steel pipes, a sealing gap is formed between the urea suction pipe and the inner wall of the first mounting hole, an expansion space is reserved for elastic deformation of the pipeline caused by urea crystallization expansion in the pipeline, no residual urea exists in the sealing gap, and the service life of the urea sensor is prolonged. The compression set and damage of the sealing ring caused by the crystallization expansibility of urea are avoided, the use performance of the sensor in an extremely cold environment is ensured, the damage and leakage of parts caused by the crystallization expansibility of the urea suction pipeline of the sensor in a low-temperature environment are effectively avoided, and the normal use of a vehicle is ensured.

Description

Technical Field

[0001] The utility model relates to the technical field of urea sensors, in particular to a urea sensor pipeline connection structure. Background Art

[0002] In the SCR aftertreatment system, the urea sensor is an integral part of the urea supply system, ensuring proper urea absorption and recirculation. Because urea crystallizes and expands (7% expansion rate) in low-temperature environments (below -11°C), the urea sensor and urea piping must meet low-temperature requirements.

[0003] Conventional solutions utilize a split-pipe structure assembled to the sensor's plastic head. This design presents a significant risk of leakage in low-temperature environments, often leading to cracking of the sensor's plastic head and displacement of the urea line. For example, the urea pump used in one Cummins product lacks a function to blow back residual urea solution in the line during shutdown, resulting in the urea intake line filling with urea solution after a shutdown. In cold climates, after a vehicle is shut down, urea in the UQS sensor's urea line will begin to crystallize due to the low temperature. Due to urea's properties, it expands by 7%, resulting in internal pressure from crystallization. Furthermore, the urea intake line in this UQS sensor solution is a split-piece structure, with stainless steel at each end and nylon in the middle. Due to differences in thermal conductivity between the materials, crystallization begins at the ends and progresses toward the middle of the line. This leaves no space for pressure relief for the urea crystals in the middle section, ultimately causing the nylon pipe to rupture due to the crystallization expansion force. The UQS sensor's urea absorption pipeline has a split structure. There is a stepped assembly surface on the pipeline. When urea crystals expand, the assembly structure inside the pipeline is subjected to axial force, which causes displacement of parts and permanent deformation and damage of seals due to compression.

[0004] Therefore, it is necessary to develop a urea sensor pipeline connection structure to solve the above problems. Utility Model Content

[0005] The technical problem to be solved by the present invention is to address the deficiencies of the above-mentioned existing technologies and provide a urea sensor pipeline connection structure. Through the new sensor pipeline structure design, the internal pressure of the pipeline caused by the low-temperature crystallization expansion of urea is effectively absorbed, thereby solving the risk of leakage of the sensor when used in a low-temperature environment.

[0006] In order to solve the above technical problems, the technical solution adopted by the present invention is:

[0007] A urea sensor pipe connection structure includes a sensor end, a urea absorbing pipe, and a urea absorbing connector. The sensor end is provided with a first mounting hole extending through a bottom wall thereof, and the top end of the urea absorbing pipe is inserted into the first mounting hole. One side of the first mounting hole is connected to a second mounting hole, and the urea absorbing connector is embedded in the second mounting hole. The urea absorbing pipe is connected to the urea absorbing connector by a sleeve connection, and the end of the urea absorbing connector away from the urea absorbing pipe is connected to an output pipe by a sleeve connection.

[0008] A restraining piece is detachably mounted on the bottom of the sensor end head for fixing the urea absorbing tube. Flared portions are provided at both ends of the first mounting hole, and two sealing rings are sleeved between the urea absorbing tube and the inner wall of the first mounting hole. The two sealing rings are respectively arranged on the inner ends of the two flared portions. An annular sleeve is installed between the sealing ring at the top and the bottom wall of the urea absorbing joint, and a conical sleeve is installed between the sealing ring at the bottom and the top wall of the restraining piece.

[0009] Preferably, an upper cover is provided on the sensor end head, and the upper cover and the top wall of the sensor end head are detachably connected by self-tapping screws, the upper cover and the top wall of the sensor end head are both provided with arc-shaped grooves, and the two arc-shaped grooves are correspondingly combined to form a second mounting hole, the outer wall of the urea absorption joint is provided with a limiting groove, and limiting blocks are integrally provided inside the two arc-shaped grooves, and the limiting blocks are correspondingly engaged with the limiting grooves.

[0010] Preferably, a gap is reserved between the urea absorbing pipe and the inner wall of the first mounting hole, and the gap is located between the two sealing rings.

[0011] Preferably, the restraint includes a toothed ring composed of a support plate and a circular plate, and the circular plate is integrally arranged at the outer top end of the support plate, and the bottom of the sensor end is provided with an undercut protrusion corresponding to the circular plate. The toothed ring is pressed onto the sensor end through the cooperation of the circular plate and the undercut protrusion, and when the support plate is installed, its top wall is tightly fitted with the bottom wall of the sensor end, and a through hole matching the outer diameter of the urea absorption tube is provided on the support plate.

[0012] Preferably, the number of the circular plates and the undercut protrusions is set to eight, and the eight circular plates and the undercut protrusions are distributed in a ring array.

[0013] Preferably, the sensor head is made of nylon plastic.

[0014] Preferably, the urea absorbing pipe and the urea absorbing joint are both made of stainless steel pipes, and the urea absorbing joint is combined with the urea absorbing pipe and then welded by argon arc.

[0015] Preferably, the urea absorbing pipeline composed of the urea absorbing pipe and the urea absorbing connector is provided as an integrally formed steel pipe structure.

[0016] The utility model has the following beneficial effects:

[0017] 1. Through the design of the urea sensor pipeline structure, the urea absorption pipeline adopts an integrated stainless steel tube, forming a sealed gap between the urea absorption pipe and the inner wall of the first mounting hole, which reserves expansion space for the elastic deformation of the pipeline caused by the expansion of urea crystals in the pipeline. There is no residual urea in the sealed gap, which avoids the permanent compression deformation and damage of the sealing ring caused by the expansion force of urea crystals, ensuring the performance of the sensor in extremely cold environments, and effectively avoiding the damage and leakage of components caused by the expansion force of urea crystals in the sensor absorption pipeline in low temperature environments, ensuring the normal use of the vehicle;

[0018] 2. A detachable restraint is installed at the bottom of the sensor end to fix the urea absorbing tube. The support plate is sleeved on the outside of the urea absorbing tube through the through hole, and then the circular plate and the undercut protrusion are used to press and bite. The top wall of the support plate fits tightly with the bottom wall of the sensor end to stably support the urea absorbing tube. The annular sleeve and the conical sleeve position and support the urea absorbing tube, which improves the sealing effect between the structures and can extend the service life of the device. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 A three-dimensional diagram of the urea sensor pipeline connection structure (assembled state) provided by the utility model;

[0020] Figure 2 A partial cutaway diagram showing the connection structure of the urea sensor pipeline provided by the present invention;

[0021] Figure 3 For this utility model Figure 2 a front view of the structure shown;

[0022] Figure 4 This is an exploded view from the first perspective of the urea sensor pipeline connection structure provided by the utility model;

[0023] Figure 5 This is an exploded view from the second perspective of the urea sensor pipeline connection structure provided by the utility model.

[0024] Among them are:

[0025] Sensor end-1; urea absorption tube-2; urea absorption connector-3; first mounting hole-4; second mounting hole-5; output tube-6; restraining member-7; sealing ring-8; annular sleeve-9; tapered sleeve-10; upper cover-11; self-tapping screw-12; limit groove-13; limit block-14;

[0026] Support plate 71; circular plate 72; undercut protrusion 73; through hole 74. DETAILED DESCRIPTION

[0027] The present invention will be further described in detail below with reference to the accompanying drawings and specific preferred embodiments.

[0028] In the description of the present invention, it should be understood that the terms "left side," "right side," "upper," "lower," etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings and are intended solely to facilitate the description of the present invention and simplify the description. They do not indicate or imply that the devices or components referred to must have a specific orientation, be constructed, or operate in a specific orientation. Terms such as "first" and "second" do not indicate the importance of a component and therefore should not be construed as limiting the present invention. The specific dimensions used in this embodiment are merely for illustrative purposes and do not limit the scope of protection of the present invention.

[0029] like Figure 1-5 As shown, a urea sensor pipeline connection structure includes a sensor end 1, a urea absorbing pipe 2 and a urea absorbing connector 3. The sensor end 1 is provided with a first mounting hole 4 running through its bottom wall, and the top end of the urea absorbing pipe 2 is inserted into the first mounting hole 4. A second mounting hole 5 is connected to one side of the first mounting hole 4, and the urea absorbing connector 3 is embedded in the second mounting hole 5. The urea absorbing pipe 2 and the urea absorbing connector 3 are sleeved and communicated. The urea absorbing pipe 2 and the urea absorbing connector 3 are both made of stainless steel pipes, and the urea absorbing connector 3 is argon arc welded with the urea absorbing pipe 2 after being combined. The inner wall of the pipe formed by the urea absorbing connector 3 and the urea absorbing pipe 2 is smooth and has no step structure. The inner wall of the pipe is made of stainless steel, which enhances the pressure-bearing capacity of the inner wall of the pipe. In addition, the crystallization time of the inner wall of the pipe is basically consistent, avoiding the difference in freezing order caused by the difference in heat conduction of different materials, so that the expansion volume of urea crystals inside the pipe can be released to the external hose, effectively absorbing the expansion force of the urea crystals.

[0030] The end of the urea absorption connector 3 away from the urea absorption pipe 2 is connected to the output pipe 6, which is a replaceable structure to facilitate the discharge of materials;

[0031] A restraining piece 7 is detachably mounted on the bottom of the sensor end 1 for fixing the urea absorbing pipe 2. Flared portions are provided at both ends of the first mounting hole 4, and two sealing rings 8 are sleeved between the urea absorbing pipe 2 and the inner wall of the first mounting hole 4. The two sealing rings 8 are respectively arranged at the inner ends of the two flared portions. An annular sleeve 9 is installed between the sealing ring 8 at the top and the bottom wall of the urea absorbing connector 3. A conical sleeve 10 is installed between the sealing ring 8 at the bottom and the top wall of the restraining piece 7 to improve the stability of the installation of the sealing ring 8. The sealing ring 8 adopts an external structure. A gap is reserved between the urea absorbing pipe 2 and the inner wall of the first mounting hole 4 to reserve expansion space for the elastic deformation of the pipe caused by the expansion of urea crystals in the pipe. The gap is located between the two sealing rings 8. There is no residual urea in the formed sealing gap, which avoids permanent compression deformation and damage of the sealing ring caused by the expansion force of the urea crystals.

[0032] Specifically, an upper cover 11 is provided on the sensor end 1, and the upper cover 11 is detachably connected to the top wall of the sensor end 1 by self-tapping screws 12. The upper cover 11 and the top wall of the sensor end 1 are both provided with arc-shaped grooves, and the two arc-shaped grooves are correspondingly combined to form a second mounting hole 5. A limiting groove 13 is provided on the outer wall of the urea absorbing joint 3, and a limiting block 14 is integrally provided inside the two arc-shaped grooves. The limiting block 14 is correspondingly engaged with the limiting groove 13, which facilitates the installation and disassembly of the urea absorbing joint 3 and has good stability after installation.

[0033] As a preferred embodiment of the restraining member 7 in the present invention:

[0034] The restraining member 7 includes a toothed ring composed of a support plate 71 and a circular plate 72, and the circular plate 72 is integrally arranged at the outer top end of the support plate 71. The bottom of the sensor terminal 1 is provided with an undercut protrusion 73 corresponding to the circular plate 72. The toothed ring is pressed on the sensor terminal 1 through the circular plate 72 and the undercut protrusion 73. This structure is convenient for installation and disassembly, thereby facilitating the assembly of the sensor terminal 1 and the urea absorbing pipe 2. When the support plate 71 is installed, its top wall is tightly fitted with the bottom wall of the sensor terminal 1, and a through hole 74 matching the outer diameter of the urea absorbing pipe 2 is provided on the support plate 71.

[0035] Specifically, the number of the circular plates 72 and the undercut protrusions 73 is set to eight, and the eight circular plates 72 and the undercut protrusions 73 are distributed in a ring array.

[0036] Specifically, the sensor head 1 is made of nylon plastic.

[0037] The urea absorption pipe 2 and the urea absorption joint 3 are respectively assembled in the first mounting hole 4 and the second mounting hole 5, and the ends of the urea absorption pipe 2 and the urea absorption joint 3 are butted together and then argon arc welding is performed. In the first mounting hole 4, two sealing rings 8 are sleeved on the outside of the urea absorption pipe 2, and an annular sleeve 9 and a tapered sleeve 10 are respectively installed on the inner ends of the two flared parts to form a sealing gap between the urea absorption pipe 2 and the inner wall of the first mounting hole 4. The annular sleeve 9 and the tapered sleeve 10 position and support the urea absorption pipe 2, thereby improving the sealing effect between the structures and reserving expansion space for the elastic deformation of the pipeline caused by the expansion of urea crystals in the pipeline. There is no residual urea in the sealing gap, thereby avoiding permanent compression deformation and damage of the sealing ring caused by the expansion force of the urea crystals.

[0038] A restraining member 7 is detachably installed at the bottom of the sensor end 1 to fix the urea absorbing tube 2. The supporting plate 71 is sleeved on the outside of the urea absorbing tube 2 through the through hole 74. Then, the circular plate 72 and the undercut protrusion 73 are used to buckle and engage. The top wall of the supporting plate 71 fits tightly with the bottom wall of the sensor end 1 to stably support the urea absorbing tube 2.

[0039] The embodiments of the present invention are described in detail above with reference to the accompanying drawings, but the present invention is not limited to the described embodiments. It is apparent to those skilled in the art that various changes, modifications, substitutions, and variations to these embodiments may be made without departing from the principles and spirit of the present invention, and these changes and modifications still fall within the scope of protection of the present invention.

Claims

1. A urea sensor pipeline connection structure, comprising a sensor end (1), a urea absorbing pipe (2) and a urea absorbing connector (3), characterized in that: A first mounting hole (4) is provided inside the sensor end (1) and passes through the bottom wall thereof, and the top end of the urea absorption tube (2) is inserted into the first mounting hole (4); one side of the first mounting hole (4) is connected to a second mounting hole (5), and the urea absorption connector (3) is embedded in the second mounting hole (5); the urea absorption tube (2) and the urea absorption connector (3) are sleeved and connected, and the end of the urea absorption connector (3) away from the urea absorption tube (2) is sleeved and connected to an output tube (6); A restraining member (7) is detachably mounted on the bottom of the sensor end (1) for fixing the urea absorbing tube (2). Both ends of the first mounting hole (4) are provided with flared portions, and two sealing rings (8) are sleeved between the urea absorbing tube (2) and the inner wall of the first mounting hole (4). The two sealing rings (8) are respectively arranged at the inner ends of the two flared portions. An annular shaft sleeve (9) is mounted between the sealing ring (8) at the top and the bottom wall of the urea absorbing connector (3), and a conical shaft sleeve (10) is mounted between the sealing ring (8) at the bottom and the top wall of the restraining member (7).

2. The urea sensor pipeline connection structure according to claim 1, characterized in that: The sensor end (1) is provided with an upper cover (11), and the upper cover (11) and the top wall of the sensor end (1) are detachably connected via self-tapping screws (12); the upper cover (11) and the top wall of the sensor end (1) are both provided with arcuate grooves, and the two arcuate grooves are correspondingly combined to form a second mounting hole (5); the outer wall of the urea absorbing joint (3) is provided with a limiting groove (13), and limiting blocks (14) are integrally provided inside the two arcuate grooves, and the limiting blocks (14) are correspondingly engaged with the limiting grooves (13).

3. The urea sensor pipeline connection structure according to claim 1, characterized in that: A gap is reserved between the urea absorbing pipe (2) and the inner wall of the first mounting hole (4), and the gap is located between the two sealing rings (8).

4. The urea sensor pipeline connection structure according to claim 1, characterized in that: The restraining member (7) includes a toothed ring composed of a support plate (71) and a circular plate (72), and the circular plate (72) is integrally arranged on the outer top end of the support plate (71). The bottom of the sensor end (1) is provided with an undercut protrusion (73) corresponding to the circular plate (72). The toothed ring is pressed onto the sensor end (1) through the circular plate (72) and the undercut protrusion (73). When the support plate (71) is installed, its top wall is tightly fitted with the bottom wall of the sensor end (1), and a through hole (74) matching the outer diameter of the urea absorption tube (2) is opened on the support plate (71).

5. The urea sensor pipeline connection structure according to claim 4, characterized in that: The number of the circular plates (72) and the undercut protrusions (73) is set to eight, and the eight circular plates (72) and the undercut protrusions (73) are distributed in a ring array.

6. The urea sensor pipeline connection structure according to claim 1, characterized in that: The sensor end (1) is made of nylon plastic.

7. The urea sensor pipeline connection structure according to claim 1, characterized in that: The urea absorbing pipe (2) and the urea absorbing joint (3) are both made of stainless steel pipes, and the urea absorbing joint (3) and the urea absorbing pipe (2) are combined and then welded by argon arc welding.

8. The urea sensor pipeline connection structure according to claim 1, characterized in that: The urea absorbing pipeline composed of the urea absorbing pipe (2) and the urea absorbing connector (3) is provided as an integrally formed steel pipe structure.

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