Ultrasonic floating injection assembly and urea injector

Abstract

The utility model relates to the field of urea injectors, and particularly discloses an ultrasonic wave floating injection assembly and a urea injector, the ultrasonic wave floating injection assembly comprises a shell, an injection pipe, a first installation shaft and a second installation shaft, an inner cavity, a liquid inlet cavity and a guide hole are arranged in the shell, and the injection pipe is installed in the inner cavity through a first elastic ring and a second elastic ring. The elastic ring not only can provide elastic floating connection for the spray pipe in the axial direction, but also can seal the liquid inlet cavity and the opening part of the guide hole through deformation, so that the spray assembly can be suitable for the use condition of high-pressure liquid so as to be compatible with an existing high-pressure urea injection pump, the structure is simple, and the design integration degree is high; and the urea liquid can dissipate heat generated during vibration friction of the first mounting shaft and the second mounting shaft through the liquid inlet cavity and the cooling channel, so that the urea injector can be used in the high-temperature environment of the SCR catalyst, and the service life and the stability of the urea injector are guaranteed.

Description

Technical Field

[0001] This utility model belongs to the field of urea injectors, and specifically relates to an ultrasonic floating injection component and a urea injector. Background Technology

[0002] As the national emission standards for motor vehicles continue to rise, stricter requirements have been put forward for limiting NOx emissions from exhaust gases. These requirements can no longer be met by simply relying on engine manufacturing processes and system calibration management. A urea atomization injection system with a larger urea supply, better atomization performance, and higher conversion efficiency is needed to match these requirements.

[0003] Traditional urea nozzles typically produce atomized particles of 0.05-0.15 mm, and the inlet pressure has a significant impact on the particle size. The allowable range of inlet pressure is narrow, making it difficult to improve atomization performance. Ultrasonic nozzles, on the other hand, utilize a transducer to vibrate the nozzle and generate ultrasonic waves. When the liquid-gas interface at the nozzle is subjected to ultrasonic waves, tension waves are formed. When the tension waves are sufficiently large, they produce very small spray particles at their peaks, achieving a particle size of approximately 0.01 mm. Furthermore, they are less affected by inlet pressure and flow rate, and have a wider allowable pressure range, making them a good upgrade solution for traditional urea nozzles under the new emission standards.

[0004] However, existing ultrasonic atomizing nozzles are typically used in low liquid pressure environments and usually require high-pressure gas for atomization. They have complex structures, low integration, and large space requirements. They are not suitable for use in high-pressure liquid injection environments and are incompatible with the urea injection pump in existing SCR systems. Furthermore, in the high-temperature environment of the SCR catalyst, there is no corresponding cooling structure to cool the high-frequency vibrating nozzle, which affects the stability and lifespan of the nozzle.

[0005] Patent document CN201920123373.6 discloses an ultrasonic nozzle capable of uniform jetting under low-velocity gas conditions. The nozzle includes an ultrasonic nozzle platform and an air cap. The air cap is mounted on the front end of the ultrasonic nozzle platform with a locking nut and sealed with an O-ring. The rear end face of the air cap has two annular grooves, and a swirling cavity is located at the center of the air cap. Annular groove one is connected to the swirling cavity via a guide groove, forming an annular gap between the swirling cavity and the ultrasonic nozzle platform. An air gap is located at the front end of the air cap, and annular groove two is connected to the air gap via a flow channel. A liquid inlet is located in the center of the ultrasonic nozzle platform, and a guide hole two communicating with the central gas inlet and annular groove one is located in the lower part of the ultrasonic nozzle platform. A guide hole one communicating with the edge gas inlet and annular groove two is also located in the lower part of the ultrasonic nozzle platform. The ultrasonic nozzle in this prior art document still suffers from structural complexity, low design integration, inapplicability to existing SCR systems, and the inability to achieve cooling.

[0006] 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

[0007] The purpose of this invention is to provide an ultrasonic floating injection component and a urea injector, thereby overcoming the shortcomings of existing ultrasonic nozzles, such as complex structure, low design integration, lack of cooling structure, and incompatibility with existing urea high-pressure injection pumps.

[0008] To achieve the above objectives, this utility model provides an ultrasonic floating jet assembly, comprising: a housing, a nozzle, and a transducer assembly. The housing has an inner cavity, the nozzle is installed in the inner cavity with its lower end extending outward from the bottom of the housing, and the transducer assembly is sleeved on the outer periphery of the nozzle and located in the inner cavity. The top and bottom of the inner cavity are respectively provided with a liquid inlet chamber and a guide hole. The top of the nozzle is provided with a first mounting shaft, and the middle of the nozzle is provided with a second mounting shaft. The first mounting shaft and the second mounting shaft are slidably inserted into the liquid inlet chamber and the guide hole, respectively. A first elastic ring and a second elastic ring are respectively sleeved on the first mounting shaft and the second mounting shaft. The nozzle is also provided with a first limiting part and a second limiting part. The first elastic ring is squeezed between the top of the inner cavity and the first limiting part, and the second elastic ring is squeezed between the bottom of the inner cavity and the second limiting part. The first elastic ring and the second elastic ring can seal the opening of the liquid inlet chamber and the opening of the guide hole.

[0009] Preferably, in the above technical solution, the housing includes a bottom shell and a top cover, the inner cavity is formed in the bottom shell and the opening of the inner cavity is located at the top of the bottom shell, the liquid inlet is formed on the lower end face of the top cover, and the lower end of the top cover can be inserted into the opening of the inner cavity and assembled with the bottom shell by locking bolts, thereby elastically compressing the first elastic ring and the second elastic ring.

[0010] Preferably, in the above technical solution, an inwardly recessed limiting groove is provided on the lower end face of the upper cover, the liquid inlet cavity is provided at the bottom of the limiting groove, the diameter of the liquid inlet cavity is smaller than the diameter of the limiting groove, the first elastic ring is installed in the limiting groove, and the outer periphery of the first elastic ring is in contact with the wall of the limiting groove.

[0011] Preferably, in the above technical solution, the diameter of the second limiting part is larger than the diameter of the second mounting shaft, and the outer periphery of the second elastic ring fits against the wall of the inner cavity.

[0012] Preferably, in the above technical solution, the liquid inlet chamber is a cylindrical cavity structure and its axis coincides with the axis of the guide hole and the axis of the nozzle.

[0013] Preferably, in the above technical solution, the transducer assembly includes a piezoelectric ceramic ring, an electrode sheet, and a pressure plate. The piezoelectric ceramic ring and the electrode sheet are located between the pressure plate and the second limiting part and are alternately stacked. The first limiting part is detachably fitted onto the nozzle and its bottom abuts against the top of the pressure plate, so as to limit the displacement of the pressure plate on the nozzle.

[0014] Preferably, in the above technical solution, the upper end face of the nozzle is provided with an inwardly recessed liquid receiving groove, and the bottom of the liquid receiving groove extends all the way to the installation position of the first elastic ring.

[0015] Preferably, in the above technical solution, an arc transition surface is provided between the bottom of the liquid tank and the side wall, and a guide surface is provided between the top of the liquid inlet cavity and the side wall.

[0016] On the other hand, to achieve the above objectives, this utility model also provides a urea injector, including the ultrasonic floating injection assembly as described above, and further including a cooling channel, a liquid inlet channel, a coolant input channel, and a coolant output channel; the cooling channel is disposed inside the housing and surrounds the periphery of the guide hole, one end of the coolant input channel and one end of the coolant output channel are respectively connected to both ends of the cooling channel, the other end of the coolant input channel and the other end of the coolant output channel extend to the top of the housing and are equipped with a first pipe connector and a second pipe connector, one end of the liquid inlet channel is connected to the top of the liquid inlet chamber, and the other end of the liquid inlet channel is equipped with a third pipe connector.

[0017] Preferably, in the above technical solution, the top of the housing is provided with a signal connector, which is electrically connected to the transducer assembly.

[0018] Compared with existing technologies, this utility model has the following beneficial effects:

[0019] 1. In this utility model, the nozzle is installed in the inner cavity of the housing via a first elastic ring and a second elastic ring. The elastic rings not only provide the nozzle with an axially elastic floating connection, but also seal the inlet cavity and guide hole through deformation, making the injection assembly suitable for high-pressure liquid use conditions and compatible with existing high-pressure urea injection pumps. Furthermore, the structure is simple and the design is highly integrated. The urea liquid flows through the liquid cavity and cooling channel, which can dissipate the heat generated by the vibration and friction of the first and second mounting shafts, thereby enabling the urea injector to be used in the high-temperature environment of the SCR catalyst, ensuring its lifespan and stability.

[0020] 2. The upper end face of the nozzle in this utility model is provided with a liquid receiving groove, which not only makes the wall thickness of the first mounting shaft thinner, thus making heat dissipation more effective and improving heat dissipation efficiency, but also helps to increase the volume of the liquid inlet chamber, thereby achieving a pressure stabilization effect; the top edge of the liquid inlet chamber is provided with a guide surface, and the bottom edge of the liquid receiving groove is provided with an arc transition surface, which not only reduces the concentrated impact of water hammer effect caused by nozzle vibration on the joint material, but also prevents urea from adhering and crystallizing on the wall.

[0021] 3. The first limiting part in this utility model can not only squeeze and contact the first elastic ring to restrict the axial movement of the nozzle, but also lock the pressure plate, further improving the design integration. Attached Figure Description

[0022] Figure 1 This is a partial cross-sectional view of the ultrasonic floating jet assembly in this utility model.

[0023] Figure 2 This is a structural diagram of a urea injector.

[0024] Figure 3 This is a partial cross-sectional view of a urea injector.

[0025] Explanation of key figure labels:

[0026] 100-Housing shell, 101-Bottom shell, 102-Top cover, 103-Locking bolt, 110-Inner cavity, 120-Liquid inlet cavity, 121-Guide surface, 130-Guide hole, 140-Limiting groove;

[0027] 200-nozzle, 210-first mounting shaft, 220-second mounting shaft, 230-first limiting part, 240-second limiting part, 250-liquid tank, 251-arc transition surface;

[0028] 300 - Transducer assembly, 310 - Piezoelectric ceramic ring, 320 - Electrode sheet, 330 - Pressure plate;

[0029] 400 - First elastic band;

[0030] 500 - Second elastic ring;

[0031] 600-Cooling channel, 610-Inlet channel, 620-Coolant input channel, 630-Coolant output channel, 640-First pipe connector, 650-Second pipe connector, 660-Third pipe connector;

[0032] 700-signal connector;

[0033] 800-Flange. Detailed Implementation

[0034] 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.

[0035] 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.

[0036] 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.

[0037] 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.

[0038] like Figures 1 to 2 As shown, the ultrasonic floating jet assembly in this embodiment includes a housing 100, a bottom shell 101, a top cover 102, a locking bolt 103, an inner cavity 110, a liquid inlet cavity 120, a guide surface 121, a guide hole 130, a limiting groove 140, a nozzle 200, a first mounting shaft 210, a second mounting shaft 220, a first limiting part 230, a second limiting part 240, a liquid reservoir 250, an arc transition surface 251, a transducer 300, a piezoelectric ceramic ring 310, an electrode sheet 320, a pressure plate 330, a first elastic ring 400, and a second elastic ring 500.

[0039] The housing 100 includes a bottom shell 101 and a top cover 102. An inner cavity 110 is formed in the bottom shell 101, with the opening of the inner cavity 110 located at the top of the bottom shell 101. A guide hole 130 is formed at the bottom of the inner cavity 110. A liquid inlet chamber 120 is formed on the lower end face of the top cover 102. Both the top cover 102 and the bottom shell 101 have corresponding ear plates on their outer peripheries. The lower end of the top cover 102 can be inserted into the opening of the inner cavity 110 and pass through... The upper cover 102 and the bottom shell 101 are assembled by tightening the locking bolt 103 onto the ear plate. The liquid inlet cavity 120 is a cylindrical cavity structure. After the upper cover 102 and the bottom shell 101 are assembled, its axis coincides with the axis of the guide hole 130. A recessed limiting groove 140 is provided on the lower end face of the upper cover 102. The liquid inlet cavity 120 is opened at the bottom of the limiting groove 140. The diameter of the liquid inlet cavity 120 is smaller than the diameter of the limiting groove 140.

[0040] A first mounting shaft 210 is provided at the top of the nozzle 200, and a second mounting shaft 220 is provided in the middle of the nozzle 200. The axes of the first mounting shaft 210 and the second mounting shaft 220 are collinear with the axis of the nozzle 200. The first mounting shaft 210 and the second mounting shaft 220 are slidably inserted into the liquid inlet chamber 120 and the guide hole 130, respectively. The diameter of the second mounting shaft 220 is larger than the diameter of the nozzle 200. A first elastic ring 400 and a second elastic ring 500 of rubber material are respectively fitted on the first mounting shaft 210 and the second mounting shaft 220. A first limiting part 230 and a second limiting part 240 are also provided on the nozzle 200. The first limiting part 230 and the second limiting part 240 are connected to the nozzle 200. The nozzle 200 is threaded to the pipe wall. The second limiting part 240 is integrally fixed to the nozzle 200 and located above the second mounting shaft 220. The diameter of the second limiting part 240 is larger than the diameter of the second mounting shaft 220. The first elastic ring 400 is squeezed between the top of the inner cavity 110 and the first limiting part 230, and its outer periphery is in contact with the wall of the limiting groove 140. The second elastic ring 500 is squeezed between the bottom of the inner cavity 110 and the second limiting part 240, and its outer periphery is in contact with the wall of the inner cavity 110. When the first elastic ring 400 and the second elastic ring 500 deform, they can seal the opening of the liquid inlet chamber 120 and the opening of the guide hole 130.

[0041] The transducer assembly 300 is fitted onto the nozzle 200 and located in the inner cavity 110. It includes an electric ceramic ring, an electrode plate 320, and a pressure plate 330. The electric ceramic ring 310 and the electrode plate 320 are located between the pressure plate 330 and the second limiting part 240 and are alternately stacked. The bottom of the first limiting part 230 abuts against the top of the pressure plate 330 to limit the displacement of the pressure plate 330 on the nozzle 200.

[0042] In addition, the upper end face of the nozzle 200 is provided with an inwardly recessed liquid reservoir 250, the bottom of the liquid reservoir 250 extends all the way to the installation position of the first elastic ring 400, an arc transition surface 251 is provided between the bottom of the liquid reservoir 250 and the side wall, and a guide surface 121 is provided between the top of the liquid inlet chamber 120 and the side wall.

[0043] Furthermore, this embodiment also discloses a urea injector, including the aforementioned ultrasonic floating injection assembly. Additionally, a cooling channel 600, a liquid inlet channel 610, a coolant input channel 620, and a coolant output channel 630 are provided within the housing 100. The cooling channel is disposed within the bottom shell 101 and surrounds the guide hole 130. The axes of the coolant input channel 620 and the coolant output channel 630 are parallel to the axis of the inner cavity 110. One end of the coolant input channel 620 and one end of the coolant output channel 630 are respectively connected to both ends of the cooling channel 600. The other ends of the coolant input channel 620 and the coolant output channel 630 extend to the upper cover. The upper cover 102 extends outward from the top of the upper cover 102. A first pipe connector 640 and a second pipe connector 650 are installed on the top of the upper cover 102. The first pipe connector 640 and the second pipe connector 650 are respectively connected to the other end of the coolant inlet channel 620 and the other end of the coolant outlet channel 630. A liquid inlet channel 610 is opened inside the upper cover 102, one end of which is connected to the top of the liquid inlet chamber 120. A third pipe connector 660 is installed at the other end of the liquid inlet channel 610. A signal connector 700 is also installed on the upper cover 102. The signal connector 700 is electrically connected to the transducer assembly 300. A flange 800 for mutual installation with the SCR catalyst is provided at the bottom of the bottom shell 101.

[0044] Next, the working principle of the ultrasonic floating jet assembly and urea injector in this embodiment will be described in detail to enable those skilled in the art to better understand this utility model:

[0045] After the bottom shell 101 and the top cover 102 are installed together, the first elastic ring 400 and the second elastic ring 500 can be subjected to the pressure of the first limiting part 230 and the second limiting part 240 in the axial direction of the nozzle 200, thereby causing the first elastic ring 400 and the second elastic ring 500 to deform in this direction, which can not only fix the nozzle 200 but also make it float in the axial direction; in addition, the first elastic ring 400 and the second elastic ring 500 can also deform in the radial direction. The side of the first elastic ring 400 is pressed against the wall of the limiting groove 140 to seal the liquid inlet chamber 120 to prevent urea liquid from entering the inner cavity 110, and the side of the second elastic ring 500 is pressed against the cavity wall of the inner cavity 110 to seal the guide hole 130 to prevent urea mist in the SCR catalyst from entering the inner cavity 110.

[0046] In use, the first pipe connector 640 and the third pipe connector 660 are connected to the high-pressure interface of the urea high-pressure injection pump, and the second pipe connector 650 is connected to the urea tank. Urea can enter the inlet chamber 120 and the cooling channel 600 through the liquid inlet channel 610 and the coolant inlet channel 620, respectively. The liquid inlet chamber can not only help increase the actual volume of the liquid inlet chamber 120 to improve the pressure stabilization effect, but also make the wall thickness at the first mounting shaft 210 thinner, thereby improving the frictional heat dissipation effect between the first mounting shaft 210 and the liquid inlet chamber 120. The flowing urea liquid in the cooling channel 600 can dissipate heat from the friction between the second mounting shaft 220 and the guide hole 130, and then flow back to the urea tank from the coolant outlet channel 630 to form a water-cooled circuit.

[0047] In summary, in this embodiment, the nozzle 200 of the ultrasonic floating injection assembly and urea injector is installed in the inner cavity 110 of the housing 100 via the first elastic ring 400 and the second elastic ring 500. The elastic rings not only provide the nozzle 200 with an axially elastic floating connection, but also seal the openings of the liquid inlet chamber 120 and the guide hole 130 through deformation, making the injection assembly suitable for high-pressure liquid use conditions and compatible with existing high-pressure urea injection pumps. Furthermore, the structure is simple and the design is highly integrated. The urea liquid can dissipate the heat generated by the vibration and friction of the first mounting shaft 210 and the second mounting shaft 220 through the liquid inlet chamber 120 and the cooling channel 600, thereby enabling the urea injector to be used in the high-temperature environment of the SCR catalyst, ensuring its lifespan and stability.

[0048] 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. An ultrasonic floating jet assembly, comprising: A housing, a nozzle, and a transducer assembly, wherein the housing has an inner cavity, the nozzle is installed in the inner cavity and its lower end extends outward from the bottom of the housing, and the transducer assembly is fitted around the outer periphery of the nozzle and located in the inner cavity, characterized in that: The inner cavity has an inlet chamber and a guide hole at its top and bottom, respectively. The nozzle has a first mounting shaft at its top and a second mounting shaft at its middle. The first and second mounting shafts are slidably inserted into the inlet chamber and the guide hole, respectively. A first elastic ring and a second elastic ring are respectively fitted on the first and second mounting shafts. The nozzle also has a first limiting part and a second limiting part. The first elastic ring is pressed between the top of the inner cavity and the first limiting part, and the second elastic ring is pressed between the bottom of the inner cavity and the second limiting part. The first and second elastic rings can seal the opening of the inlet chamber and the opening of the guide hole.

2. The ultrasonic floating jet assembly according to claim 1, characterized in that, The housing includes a bottom shell and a top cover. The inner cavity is formed in the bottom shell and the opening of the inner cavity is located at the top of the bottom shell. The liquid inlet is formed on the lower end face of the top cover. The lower end of the top cover can be inserted into the opening of the inner cavity and assembled with the bottom shell by locking bolts, thereby elastically compressing the first elastic ring and the second elastic ring.

3. The ultrasonic floating jet assembly according to claim 2, characterized in that, A recessed limiting groove is provided on the lower end face of the upper cover. The liquid inlet chamber is located at the bottom of the limiting groove. The diameter of the liquid inlet chamber is smaller than the diameter of the limiting groove. The first elastic ring is installed in the limiting groove, and the outer periphery of the first elastic ring is in contact with the wall of the limiting groove.

4. The ultrasonic floating jet assembly according to claim 3, characterized in that, The diameter of the second limiting part is larger than the diameter of the second mounting shaft, and the outer periphery of the second elastic ring fits against the wall of the inner cavity.

5. The ultrasonic floating jet assembly according to claim 1, characterized in that, The inlet chamber has a cylindrical cavity structure and its axis coincides with the axis of the guide hole and the axis of the nozzle.

6. The ultrasonic floating jet assembly according to claim 1, characterized in that, The transducer assembly includes a piezoelectric ceramic ring, an electrode sheet, and a pressure plate. The piezoelectric ceramic ring and the electrode sheet are located between the pressure plate and the second limiting part and are alternately stacked. The first limiting part is detachably fitted onto the nozzle and its bottom abuts against the top of the pressure plate to limit the displacement of the pressure plate on the nozzle.

7. The ultrasonic floating jet assembly according to claim 1, characterized in that, The upper end face of the nozzle is provided with an inwardly recessed liquid-containing groove, the bottom of which extends all the way to the installation position of the first elastic ring.

8. The ultrasonic floating jet assembly according to claim 7, characterized in that, The liquid tank has an arc transition surface between its bottom and sidewall, and the liquid inlet cavity has a guide surface between its top and sidewall.

9. A urea injector, comprising the ultrasonic floating injection assembly as described in any one of claims 1 to 8, characterized in that: It also includes a cooling channel, a liquid inlet channel, a coolant input channel, and a coolant output channel; the cooling channel is disposed inside the housing and surrounds the periphery of the guide hole, one end of the coolant input channel and one end of the coolant output channel are respectively connected to the two ends of the cooling channel, the other end of the coolant input channel and the other end of the coolant output channel extend to the top of the housing and are equipped with a first pipe connector and a second pipe connector, one end of the liquid inlet channel is connected to the top of the liquid inlet chamber, and the other end of the liquid inlet channel is equipped with a third pipe connector.

10. The urea injector according to claim 9, characterized in that, The top of the housing is provided with a signal connector, which is electrically connected to the transducer assembly.

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