Vehicle-mounted urea concentration detection device and engine tail gas treatment urea system

Abstract

The utility model provides a vehicle-mounted urea concentration detection device and an engine tail gas treatment urea system, and relates to the technical field of engines. The detection part comprises a detection body and a tension detector; the detection body is connected with the tension detector; the detection body is arranged in a urea solution of the vehicle-mounted urea box; the tension detector is used for detecting upward tension of the detection body when the detection body is placed in a urea solution of the vehicle-mounted urea box; the protective cover covers the detection part; the fixing part is used for fixing the detection part in the vehicle-mounted urea box; the processing part is connected with the detection part and used for receiving the pulling force detected by the detection part and determining the urea concentration in the vehicle-mounted urea box based on the pulling force detected by the detection part. According to the embodiment of the utility model, the urea concentration is determined through the detection part, the structure is simpler, and meanwhile, the problem that the accuracy of the detected concentration is lower due to the use of a sensor is avoided.

Description

Technical Field

[0001] The utility model relates to the technical field of engines, in particular to a vehicle-mounted urea concentration detection device and an engine exhaust gas treatment urea system. Background Art

[0002] With the implementation of the National VI and Non-road IV emission regulations for heavy-duty engine commercial vehicles, the SCR (Selective Catalytic Reduction) route has become the mainstream, and the SCR route requires monitoring of urea concentration. At present, the on-board urea concentration measurement uses a pressure detection unit to detect the pressure applied by the urea solution inside the urea tank to the bottom wall of the urea tank, and a liquid level detection unit to obtain the actual liquid level of the urea solution at the location of the pressure detection unit in the urea tank; then the density of the urea solution is calculated based on the actual liquid level of the urea solution at the location of the pressure detection unit and the pressure applied by the urea solution inside the urea tank to the bottom wall of the urea tank; then the concentration of the urea solution is calculated based on the density of the urea solution and the density of water.

[0003] The liquid level detection unit includes a liquid level sensor, an inclination sensor, and an acceleration sensor. Only when multiple sensors work together can the concentration of the solution be measured. When there are bubbles or impurities attached to the sensor probe, the urea concentration based on ultrasonic measurement will be inaccurate and misjudged as an abnormal urea concentration, which will have a great impact on the normal operation and market maintenance of the vehicle. Utility Model Content

[0004] The utility model provides a vehicle-mounted urea concentration detection device and an engine exhaust gas treatment urea system, which can determine the urea concentration by immersing a detection component in a urea solution in a urea tank. Compared with the prior art, the utility model has a simpler structure and avoids the problem of low accuracy of the detected concentration due to the use of a sensor.

[0005] In a first aspect, an embodiment of the utility model provides a vehicle-mounted urea concentration detection device, comprising:

[0006] A detection component, the detection component is arranged in the vehicle-mounted urea tank; the detection component comprises a detection body and a tension detection meter; the detection body is connected to the tension detection meter; the detection body is placed in the urea solution of the vehicle-mounted urea tank; the tension detection meter is used to detect the upward pulling force when the detection body is placed in the urea solution of the vehicle-mounted urea tank;

[0007] The protective cover covers the outside of the detection component; the protective cover is provided with a connecting component, so that the urea solution in the protective cover is connected with the urea solution outside the protective cover through the connecting component;

[0008] A fixing component, wherein the fixing component is used to fix the detection component in the protective cover so that the detection component is always vertical to the ground during the shaking of the urea solution in the vehicle-mounted urea tank;

[0009] A processing component is connected to the detection component and is used to receive the pulling force detected by the detection component, and determine the urea concentration in the vehicle-mounted urea tank based on the pulling force detected by the detection component.

[0010] In the above-mentioned device, the detection body included in the detection component is placed in the urea solution of the vehicle-mounted urea tank. The tension detector included in the detection component detects the upward pulling force of the buoyancy member in the urea solution, and the urea concentration is determined by the detected tension. In this way, the urea concentration is determined by the relationship between the buoyancy. Compared with the prior art, the structure is simpler and the problem of low accuracy of the detected concentration due to the use of the sensor is avoided.

[0011] In a possible implementation, the detection body is a water drop-shaped buoyancy ball.

[0012] In a possible implementation, the fixing component includes a first fixing component and a second fixing component;

[0013] One end of the first fixing component is fixedly connected to the tension detector;

[0014] The other end of the first fixing component and one end of the second fixing component are movably connected, so that the other end of the first fixing component rotates in one end of the second fixing component, so that the detection component is always vertical to the ground during the shaking of the urea solution in the vehicle-mounted urea tank;

[0015] The other end of the second fixing component is fixedly connected inside the protective cover.

[0016] In one possible implementation, wherein:

[0017] The other end of the first fixing member is spherical in shape;

[0018] One end of the second fixing member is in the shape of a groove;

[0019] The other end of the first fixing component is embedded in one end of the second fixing component.

[0020] In a possible implementation, the communication component includes a plurality of holes;

[0021] A plurality of holes are respectively arranged on the top of the protective cover and the side of the protective cover; the holes arranged on the side of the protective cover are close to the bottom of the protective cover.

[0022] In one possible implementation, wherein:

[0023] The protective cover is fixed on the bottom of the urea tank.

[0024] In a second aspect, an embodiment of the utility model provides a urea system for treating engine exhaust, comprising: a urea tank, and a vehicle-mounted urea concentration detection device according to any one of the embodiments of the first aspect;

[0025] The urea tank is used to hold urea solution;

[0026] The vehicle-mounted urea concentration detection device is used to detect the concentration of the urea solution in the urea tank.

[0027] In addition, the technical effects brought about by the implementation method of the second aspect can refer to the technical effects brought about by different implementation methods in the first aspect, and will not be repeated here.

[0028] It should be understood that the above general description and the following detailed description are exemplary and explanatory only and are not restrictive of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 A structural diagram of a vehicle-mounted urea concentration detection device provided in an embodiment of the utility model;

[0030] Figure 2 A structural diagram of a detection body subjected to force in a urea solution provided by an embodiment of the utility model;

[0031] Figure 3 This is a structural diagram of a vehicle-mounted urea concentration detection device when the vehicle is tilted, provided in an embodiment of the utility model. DETAILED DESCRIPTION

[0032] In order to make the purpose, technical solution and advantages of the utility model clearer, the utility model will be further described in detail below in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments of the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0033] Combination Figure 1 As shown, the embodiment of the utility model provides a vehicle-mounted urea concentration detection device, including: a detection component 110, a fixing component 120, and a processing component 130;

[0034] The detection component 110 is arranged in the vehicle-mounted urea tank 100; the detection component 110 includes a detection body 1 and a tension detection meter 2; the detection body 1 is connected to the tension detection meter 2; the detection body 1 is placed in the urea solution of the vehicle-mounted urea tank; the tension detection meter 2 is used to detect the upward pulling force when the detection body 1 is placed in the urea solution of the vehicle-mounted urea tank;

[0035] A protective cover 5 is provided on the outside of the detection component; a connecting component is provided on the protective cover 5 so that the urea solution in the protective cover 5 is connected with the urea solution outside the protective cover through the connecting component;

[0036] The fixing component 120 is used to fix the detection component 110 in the protective cover 5, so that the detection component 110 is always vertical to the ground during the shaking of the urea solution in the vehicle-mounted urea tank;

[0037] The processing component 130 is connected to the detection component 110 , and is used to receive the pulling force detected by the detection component 110 , and determine the urea concentration in the vehicle-mounted urea tank based on the pulling force detected by the detection component 110 .

[0038] The height of the detection body should be determined according to the shaking of the urea solution in the urea tank. When the detection body is at the maximum inclination angle φ of the vehicle in the front, rear and left and right directions, the detection body should be adjusted according to the shaking of the urea solution in the urea tank. Figure 3 As shown, the detection bodies are all below the liquid surface of the solution, ensuring the effectiveness of the solution concentration measurement.

[0039] The tension tester 2 must be urea-corrosion-resistant and have corresponding solution seals.

[0040] In the processing unit 130, based on the Archimedean buoyancy principle, the buoyancy of the test object in the urea solution of the vehicle-mounted urea tank is equal to the weight of the urea solution displaced by the test object, that is, F 浮力 =ρ 溶液 *g*V 检测体 . According to the balance of forces, combined Figure 2 As shown, the test body 1 receives vertical downward gravity, upward buoyancy and upward pulling force; that is, F 浮力 =G 重力 -F 拉力 , thus the test formula of solution density is obtained: ρ 溶液 =(G 重力 -F 拉力 )÷(g*V 检测体 ).

[0041] For urea solution, since the volume of urea dissolved in water is basically equal to the volume of water, C concentration = (M solution - M water) ÷ M solution = (ρ solution - ρ water) ÷ ρ solution. Urea concentration is:

[0042]

[0043] The detection component 110 detects the upward F 拉力 The data is sent to the processing component 130, and the processing component 130 can determine the concentration of urea based on the above relationship.

[0044] To ensure that the above device will not be inaccurate due to the large shaking of the urea solution in the urea tank during the driving of the vehicle, the concentration test is only allowed when the vehicle is powered on with the key in the ON position or the vehicle is started in the original operation stage (that is, the vehicle cannot be driven on the road). To avoid the influence of slight shaking on the measurement, the concentration calculated by the tension tester is processed by mean filtering to obtain a more stable concentration value.

[0045] That is, the tension values ​​of the tension detector are obtained multiple times, the concentration is calculated according to the tension values, and the average value is calculated based on the multiple concentrations, and the average value is used as the final urea concentration.

[0046] This method relies on a simple buoyancy principle and can convert the concentration of urea solution through a tension measurement. Compared with the ultrasonic principle and the liquid pressure principle, it reduces the dependence on complex sensors, has a simple system and obvious cost advantages.

[0047] At the same time, compared with the existing system based on liquid pressure, there is no need to rely on the solution level height, vehicle inclination angle, and vehicle acceleration, which can significantly improve the reliability of the measurement system.

[0048] The detection body 1 is a water drop-shaped buoyancy ball. This shape of the detection body can reduce bubbles on the surface, ensure the accuracy of the buoyancy of the detection body 1, and avoid inaccurate calculation due to a large number of bubbles on the surface.

[0049] Wherein, the fixing component 120 includes a first fixing component 3 and a second fixing component 4;

[0050] One end of the first fixing component 3 is fixedly connected to the tension detector 2. Such a fixed connection ensures that when the tension detector 2 shakes with the shaking of the urea solution in the urea tank, the connection between the one end of the first fixing component 3 and the tension detector 2 will not move.

[0051] The other end of the first fixing component 3 and one end of the second fixing component 4 are movably connected, so that the other end of the first fixing component 3 rotates in one end of the second fixing component 4, so that the detection component is always vertical to the ground during the shaking of the urea solution in the vehicle-mounted urea tank;

[0052] The other end of the second fixing component 4 is fixedly connected in the vehicle-mounted urea tank.

[0053] in:

[0054] The other end of the first fixing member 3 is spherical in shape;

[0055] One end of the second fixing member 4 is in the shape of a groove;

[0056] The other end of the first fixing component 3 is embedded in one end of the second fixing component 4 .

[0057] like Figure 1 As shown, the groove of the second fixing component 4 is a circular groove, and the circular groove of the second fixing component 4 fits with the spherical shape of the first fixing component 3. In this way, when the urea solution in the vehicle-mounted urea tank shakes and induces the tension detector to shake, since the other end of the second fixing component 4 is fixed in the urea tank, the other end of the first fixing component 3 will also rotate in one end of the second fixing component 4, which will not affect the concentration detection.

[0058] The fixing component arranges the detection component near the bottom of the vehicle-mounted urea tank.

[0059] The other end of the first fixing component 3 may also be configured as a universal joint structure with direction adjustment.

[0060] wherein the communication component comprises a plurality of holes;

[0061] A plurality of holes are respectively arranged on the top and the side of the protective cover; the holes arranged on the side of the protective cover are close to the bottom of the protective cover. Figure 3 As shown, there are 6 holes, holes 6 and 7 are arranged on the top of the protective cover 5, holes 8 and 9 are arranged on the left side of the protective cover 5, and holes 10 and 11 are arranged on the right side of the protective cover 5.

[0062] Wherein: the protective cover 5 is fixed on the bottom of the urea tank.

[0063] The size of the internal space of the protective cover 5 needs to be such that when the detection component is tilted, the detection object does not touch the wall of the protective cover 5. The function of the protective cover 5 is to reduce the fluctuation amplitude of the solution in the detection area of ​​the protective cover 5 when the solution is shaking.

[0064] In the above device, for the vehicle-mounted urea tank storing urea solution, new urea is generally added when the vehicle is parked. When no urea is added, the urea concentration is a fixed value. Therefore, the urea concentration can be detected only when the vehicle is parked or in situ.

[0065] The concentration of the urea solution under parking conditions can be obtained by calculating the density of the urea solution, which can be obtained by the buoyancy of a buoyancy ball of a fixed volume in the solution, that is, Fbuoyancy=ρsolution*g*Vbuoyancyball.

[0066] In order to ensure that the concentration can be measured by the buoyancy principle at different vehicle inclination angles (uphill and downhill, left and right inclined roads), the entire measurement system must have the structural characteristics of vertical maintenance.

[0067] In order to ensure the original engine running condition and to measure the concentration under the slight vibration of the vehicle, the system sets up a detection device shield structure with the ability to resist solution shaking. At the same time, the small fluctuation signal value is filtered through the mean filtering method.

[0068] The detection body adopts a water drop design with a curved surface tension structure, which can reduce the number of bubbles attached and reduce the impact on buoyancy measurement.

[0069] The utility model discloses an engine exhaust gas treatment urea system, comprising: a urea tank, and the above-mentioned vehicle-mounted urea concentration detection device;

[0070] The urea tank is used to hold urea solution;

[0071] The vehicle-mounted urea concentration detection device is used to detect the concentration of the urea solution in the urea tank.

[0072] Although the preferred embodiments of the present invention have been described, those skilled in the art may make other changes and modifications to these embodiments once they have learned the basic creative concept. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications falling within the scope of the present invention.

[0073] Obviously, those skilled in the art can make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include these modifications and variations.

Claims

1. A vehicle-mounted urea concentration detection device, characterized in that: include: A detection component, wherein the detection component is arranged in the vehicle-mounted urea tank; The detection component includes a detection body and a tension detection meter; The detection body is connected to the tension detector; the detection body is placed in the urea solution of the vehicle-mounted urea tank; the tension detector is used to detect the upward pulling force when the detection body is placed in the urea solution of the vehicle-mounted urea tank; A protective cover, covering the outside of the detection component; a connecting component is provided on the protective cover, so that the urea solution in the protective cover is connected with the urea solution outside the protective cover through the connecting component; A fixing component, wherein the fixing component is used to fix the detection component in the protective cover so that the detection component is always vertical to the ground during the shaking of the urea solution in the vehicle-mounted urea tank; A processing component is connected to the detection component and is used to receive the pulling force detected by the detection component, and determine the urea concentration in the vehicle-mounted urea tank based on the pulling force detected by the detection component.

2. The vehicle-mounted urea concentration detection device according to claim 1, characterized in that: The detection body is a water drop-shaped buoyancy ball.

3. The vehicle-mounted urea concentration detection device according to claim 1, characterized in that: The fixing component includes a first fixing component and a second fixing component; One end of the first fixing component is fixedly connected to the tension detector; The other end of the first fixing component and one end of the second fixing component are movably connected, so that the other end of the first fixing component rotates in one end of the second fixing component, so that the detection component is always vertical to the ground during the shaking of the urea solution in the vehicle-mounted urea tank; The other end of the second fixing component is fixedly connected inside the protective cover.

4. The vehicle-mounted urea concentration detection device according to claim 3, characterized in that: in: The other end of the first fixing member is spherical in shape; One end of the second fixing member is in the shape of a groove; The other end of the first fixing component is embedded in one end of the second fixing component.

5. The vehicle-mounted urea concentration detection device according to claim 1, characterized in that: in, The fixing component arranges the detection component near the bottom of the vehicle-mounted urea tank.

6. The vehicle-mounted urea concentration detection device according to claim 1, characterized in that: The communication component includes a plurality of holes; A plurality of holes are respectively arranged on the top of the protective cover and the side of the protective cover; the holes arranged on the side of the protective cover are close to the bottom of the protective cover.

7. The vehicle-mounted urea concentration detection device according to claim 1, characterized in that: in: The protective cover is fixed on the bottom of the urea tank.

8. An engine exhaust treatment urea system, characterized in that: include: Urea tank, a vehicle-mounted urea concentration detection device according to any one of claims 1 to 7; The urea tank is used to hold urea solution; The vehicle-mounted urea concentration detection device is used to detect the concentration of the urea solution in the urea tank.

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