Engine aftertreatment device

Abstract

The present invention discloses an engine aftertreatment device, and relates to the technical field of engine exhaust treatment. The engine aftertreatment device comprises an evaporation chamber, a urea tank and an exhaust pipe. The urea tank comprises a pressure chamber, a piston is movably arranged in the pressure chamber, the piston separates the pressure chamber into a pressure cavity and a urea cavity, the pressure cavity is connected with the evaporation chamber, the urea cavity is connected with the exhaust pipe, the urea cavity is filled with urea solution, the evaporation chamber is arranged in contact with the exhaust pipe, a phase change medium is arranged in the evaporation chamber, the evaporation chamber can absorb the heat on the exhaust pipe when the engine is started, so that the phase change medium is gasified and expanded, thereby pressing the urea solution in the urea cavity into the exhaust pipe through the piston. Compared with the prior art, the engine aftertreatment device provided by the present invention can reduce the use of assembly parts, has a simple and compact structure, occupies a small space, has a low production cost, is safe and reliable, and has strong practicality.

Description

Technical Field

[0001] The present invention relates to the technical field of engine exhaust treatment, and in particular to an engine after-treatment device. Background Art

[0002] At present, the national emission standards require that the emissions of construction machinery must meet the National IV requirements. The method of treating exhaust gas by National IV engines mostly adopts selective catalytic reduction technology. Compared with National III engines, urea tanks, urea pumps and other working devices need to be installed. This not only takes up a large space, but also increases the cost of the whole vehicle and the possibility of machine failure. In addition, the urea pump integrates parts such as motor pump, air filter, reverse valve and electrical components, with a complex structure and high production cost.

[0003] In view of this, it is particularly important to design and manufacture an engine after-treatment device with a simple structure, especially in industrial production. Summary of the invention

[0004] The object of the present invention is to provide an engine aftertreatment device with a simple and compact structure, small space occupation, capable of reducing the use of assembly parts, low production cost, safety, reliability and strong practicality.

[0005] The present invention is achieved by adopting the following technical solutions.

[0006] An engine aftertreatment device comprises an evaporation chamber, a urea tank and an exhaust pipe. The urea tank comprises a pressure chamber. A piston is movably arranged in the pressure chamber. The piston separates the pressure chamber into a pressure cavity and a urea cavity. The pressure cavity is communicated with the evaporation chamber. The urea cavity is communicated with the exhaust pipe. The urea cavity is filled with urea solution. The evaporation chamber is arranged in contact with the exhaust pipe. A phase change medium is arranged in the evaporation chamber. The evaporation chamber can absorb heat from the exhaust pipe when the engine is started, so that the phase change medium is gasified and expanded, thereby pressing the urea solution in the urea cavity into the exhaust pipe through the piston.

[0007] Furthermore, the urea tank also includes a storage chamber, which is fixedly connected to the pressure chamber and communicated with the urea cavity, and the storage chamber is used to store the urea solution.

[0008] Furthermore, the urea tank also includes a suction pipe and a first one-way valve. The suction pipe is fixedly connected to the storage chamber and communicated with the urea cavity. The first one-way valve is installed on the suction pipe. The first one-way valve is used to prevent the urea solution in the urea cavity from flowing into the storage chamber.

[0009] Furthermore, the storage chamber is provided with an injection port, and the injection port is used to replenish urea solution into the storage chamber.

[0010] Furthermore, the storage chamber is provided with a breathing valve, which is used to communicate with the outside atmosphere when the air pressure in the storage chamber exceeds or falls below a preset air pressure range, so as to prevent the storage chamber from being damaged.

[0011] Furthermore, the engine aftertreatment device also includes an injection pipe and a second one-way valve, one end of the injection pipe is connected to the urea cavity, and the other end is connected to the exhaust pipe. The second one-way valve is installed on the injection pipe, and the second one-way valve is used to prevent the urea solution in the exhaust pipe from flowing into the urea cavity.

[0012] Furthermore, the engine aftertreatment device also includes a urea filter element, which is installed on the injection pipe and is used to filter the urea solution.

[0013] Furthermore, the engine after-treatment device also includes a temperature sensor, a pressure sensor, a regulating valve and a controller. The temperature sensor is installed in the exhaust pipe, and the pressure sensor and the regulating valve are both installed in the injection pipe. The temperature sensor, the pressure sensor and the regulating valve are all connected to the controller. The temperature sensor is used to send a first control signal to the controller when it detects that the temperature in the exhaust pipe reaches a preset temperature. The pressure sensor is used to send a second control signal to the controller when it detects that the pressure in the injection pipe reaches a preset pressure. The controller is used to control the regulating valve to open when the first control signal and the second control signal are received at the same time.

[0014] Furthermore, a reaction chamber is arranged in the exhaust pipe, the exhaust pipe has an air outlet, and the reaction chamber is arranged between the injection pipe and the air outlet.

[0015] Furthermore, the evaporation chamber is in a hollow column shape, and the evaporation chamber is sleeved outside the exhaust pipe.

[0016] The engine aftertreatment device provided by the present invention has the following beneficial effects:

[0017] The engine aftertreatment device provided by the present invention comprises a urea tank including a pressure chamber, a piston is movably arranged in the pressure chamber, the piston separates the pressure chamber into a pressure cavity and a urea cavity, the pressure cavity is connected with an evaporation chamber, the urea cavity is connected with an exhaust pipe, a urea solution is contained in the urea cavity, the evaporation chamber is arranged in contact with the exhaust pipe, a phase change medium is arranged in the evaporation chamber, the evaporation chamber can absorb the heat on the exhaust pipe when the engine is started, so that the phase change medium is gasified and expanded, thereby pressing the urea solution in the urea cavity into the exhaust pipe through the piston. Compared with the prior art, the engine aftertreatment device provided by the present invention can reduce the use of assembly parts due to the use of the phase change medium arranged in the evaporation chamber and the piston movably arranged in the pressure chamber, and has a simple and compact structure, small space occupation, low production cost, safety and reliability, and strong practicality. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for use in the embodiments are briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present invention and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without creative work.

[0019] Figure 1 A schematic diagram of the structure of the engine after-treatment device provided by an embodiment of the present invention connected to the engine;

[0020] Figure 2 A schematic diagram of the structure of an engine post-processing device provided by an embodiment of the present invention;

[0021] Figure 3 A schematic diagram of the structure of a urea tank in an engine post-treatment device provided by an embodiment of the present invention;

[0022] Figure 4 A schematic structural diagram of an engine after-treatment device provided in an embodiment of the present invention in which an exhaust pipe is respectively connected to an evaporation chamber and an injection pipe.

[0023] Icons: 100-engine aftertreatment device; 110-evaporation chamber; 120-urea tank; 121-pressure chamber; 122-piston; 123-storage chamber; 124-liquid suction tube; 125-first one-way valve; 126-injection port; 127-breathing valve; 130-exhaust pipe; 131-reaction chamber; 132-air outlet; 140-injection pipe; 150-second one-way valve; 160-urea filter element; 170-temperature sensor; 180-pressure sensor; 190-regulating valve; 200-controller; 210-pressure cavity; 220-urea cavity; 300-engine. DETAILED DESCRIPTION

[0024] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Generally, the components of the embodiments of the present invention described and shown in the drawings here can be arranged and designed in various different configurations.

[0025] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the invention claimed for protection, but merely represents selected embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0026] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, further definition and explanation thereof is not required in subsequent drawings.

[0027] In the description of the present invention, it should be noted that the terms "inside", "outside", "upper", "lower", "horizontal", etc. indicate the orientation or position relationship based on the orientation or position relationship shown in the drawings, or the orientation or position relationship in which the product of the invention is usually placed when in use, which is only for the convenience of describing the present invention and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", "third", etc. are only used to distinguish the description, and cannot be understood as indicating or implying relative importance.

[0028] In the description of the present invention, it is also necessary to explain that, unless otherwise clearly specified and limited, the terms "set", "connect", "install", and "connect" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0029] Some embodiments of the present invention are described in detail below in conjunction with the accompanying drawings. In the absence of conflict, the features of the following embodiments can be combined with each other.

[0030] Example

[0031] Please refer to Figure 1 The embodiment of the present invention provides an engine post-processing device 100 for processing the exhaust gas generated by the engine 300. The structure is simple and compact, occupies a small space, can reduce the use of assembly parts, has low production cost, is safe and reliable, and has strong practicality.

[0032] In this embodiment, the engine post-processing device 100 is applied to engineering machinery such as excavators, and the engine post-processing device 100 can purify the exhaust gas generated by the engine 300 in the engineering machinery when it is operating, so that a catalytic reduction reaction occurs, and then the exhaust gas that meets the National IV standard is discharged after the reaction. However, it is not limited to this. In other embodiments, the engine post-processing device 100 can also be applied to automobiles to purify the exhaust gas generated by the engine 300 of the automobile, and the application scenario of the engine post-processing device 100 is not specifically limited.

[0033] Please refer to Figure 2 and Figure 3The engine aftertreatment device 100 includes an evaporation chamber 110, a urea tank 120, an exhaust pipe 130, an injection pipe 140, a second one-way valve 150, a urea filter element 160, a temperature sensor 170, a pressure sensor 180, a regulating valve 190 and a controller 200. The urea tank 120 includes a pressure chamber 121, in which a piston 122 is movably arranged, and the piston 122 separates the pressure chamber 121 into a pressure cavity 210 and a urea cavity 220. In this embodiment, the piston 122 can slide in the pressure chamber 121 to increase the volume of the pressure cavity 210 and reduce the volume of the urea cavity 220 or reduce the volume of the pressure cavity 210 and increase the volume of the urea cavity 220. The pressure cavity 210 is connected to the evaporation chamber 110, and a phase change medium (not shown in the figure) is arranged in the evaporation chamber 110, and the phase change medium can enter the pressure cavity 210 from the evaporation chamber 110. The urea cavity 220 is in communication with the exhaust pipe 130. The urea cavity 220 contains a urea solution (not shown in the figure). The urea solution can enter the exhaust pipe 130 from the urea cavity 220. The evaporation chamber 110 is arranged in close contact with the exhaust pipe 130. The heat of the high-temperature exhaust gas generated after the engine 300 is started can be transferred to the evaporation chamber 110 through the exhaust pipe 130. The evaporation chamber 110 can absorb the heat on the exhaust pipe 130 when the engine 300 is started, so that the phase change medium is vaporized and expanded. After the phase change medium is vaporized, it enters the pressure cavity 210, so that the pressure in the pressure cavity 210 increases, so that the urea solution in the urea cavity 220 is pressed into the exhaust pipe 130 through the piston 122, so that the urea solution and the exhaust gas undergo a catalytic reduction reaction, thereby achieving post-treatment of the exhaust gas.

[0034] It should be noted that the injection pipe 140 is disposed between the urea cavity 220 and the exhaust pipe 130, one end of the injection pipe 140 is in communication with the urea cavity 220, and the other end is in communication with the exhaust pipe 130, and the urea solution in the urea cavity 220 can be injected into the exhaust pipe 130 through the injection pipe 140 to increase the contact area between the urea solution and the exhaust gas, improve the efficiency of the catalytic reduction reaction, and thus improve the purification effect. The second one-way valve 150 is installed on the injection pipe 140, and the second one-way valve 150 only allows the urea solution in the injection pipe 140 to flow from the urea cavity 220 to the exhaust pipe 130, and does not allow the urea solution in the injection pipe 140 to flow from the exhaust pipe 130 to the urea cavity 220, and the second one-way valve 150 is used to prevent the urea solution in the exhaust pipe 130 from flowing back into the urea cavity 220. The urea filter element 160 is installed on the injection pipe 140 and is used to filter and remove impurities from the urea solution so that the urea solution sprayed from the injection pipe 140 is pure and free of impurities, thereby preventing system failure caused by impurities.

[0035] It is worth noting that the temperature sensor 170 is installed in the exhaust pipe 130, and the temperature sensor 170 is used to detect the temperature in the exhaust pipe 130. The pressure sensor 180 and the regulating valve 190 are both installed in the injection pipe 140, and the pressure sensor 180 is used to detect the pressure in the injection pipe 140, and the regulating valve 190 is used to open or close the injection pipe 140. The temperature sensor 170, the pressure sensor 180 and the regulating valve 190 are all connected to the controller 200, and the temperature sensor 170 is used to send a first control signal to the controller 200 when it is detected that the temperature in the exhaust pipe 130 reaches a preset temperature, and the pressure sensor 180 is used to send a second control signal to the controller 200 when it is detected that the pressure in the injection pipe 140 reaches a preset pressure, and the controller 200 is used to control the regulating valve 190 to open when the first control signal and the second control signal are received at the same time, so that the injection pipe 140 sprays urea solution into the exhaust pipe 130.

[0036] Specifically, when the engine 300 is started, high-temperature exhaust gas is output into the exhaust pipe 130. The high-temperature exhaust gas transfers heat to the phase change medium through the evaporation chamber 110. The phase change medium absorbs heat and vaporizes to push the piston 122 to slide, so that the pressure in the urea cavity 220 and the injection pipe 140 increases until the preset pressure is reached, so that the pressure sensor 180 sends a first control signal to the controller 200; and the temperature of the high-temperature exhaust gas is originally greater than the preset temperature. When the high-temperature exhaust gas is discharged to the detection position of the temperature sensor 170, the temperature sensor 170 sends a second control signal to the controller 200.

[0037] In this embodiment, the regulating valve 190 is a solenoid valve. Under the control of the controller 200, the regulating valve 190 can adjust the injection amount according to the working conditions, that is, adjust the flow rate of the urea solution sprayed out, so that the volume of the sprayed urea solution matches the amount of exhaust gas discharged by the engine 300, thereby preventing the waste or shortage of urea solution.

[0038] It should be noted that the urea tank 120 further includes a storage chamber 123, a liquid suction pipe 124 and a first one-way valve 125. The storage chamber 123 is fixedly connected to the pressure chamber 121, and the storage chamber 123 is arranged below the pressure chamber 121. In this embodiment, the storage chamber 123 and the pressure chamber 121 are integrally formed to improve the connection strength. The storage chamber 123 is connected to the urea cavity 220, and the storage chamber 123 is used to store the urea solution and replenish the urea solution into the urea cavity 220. Specifically, the evaporation chamber 110 can cool down and release heat when the engine 300 is shut down, so that the phase change medium liquefies and shrinks, and the volume of the phase change medium decreases after liquefaction, so that the air pressure in the pressure cavity 210 decreases. In this way, under the action of the pressure difference, the urea solution in the storage chamber 123 is sucked into the urea cavity 220 through the piston 122, thereby realizing the replenishment of the urea solution.

[0039] In this embodiment, the liquid suction pipe 124 is fixedly connected to the storage chamber 123 and communicated with the urea cavity 220, and the urea solution in the storage chamber 123 can enter the urea cavity 220 through the liquid suction pipe 124. The first one-way valve 125 is installed on the liquid suction pipe 124, and the first one-way valve 125 only allows the urea solution in the liquid suction pipe 124 to flow from the storage chamber 123 to the urea cavity 220, and does not allow the urea solution in the liquid suction pipe 124 to flow from the urea cavity 220 to the storage chamber 123. The first one-way valve 125 is used to prevent the urea solution in the urea cavity 220 from flowing back into the storage chamber 123.

[0040] It should be noted that the storage chamber 123 is provided with an injection port 126, which is used to add urea solution to the storage chamber 123. The staff can inject urea solution from the outside into the storage chamber 123 through the injection port 126. The storage chamber 123 is provided with a breathing valve 127, which is used to communicate with the outside atmosphere when the air pressure in the storage chamber 123 exceeds or is lower than the preset air pressure range to prevent the storage chamber 123 from being damaged. Specifically, the breathing valve 127 can be opened to communicate with the outside atmosphere when the air pressure in the storage chamber 123 exceeds the maximum air pressure in the preset air pressure range to discharge part of the air in the storage chamber 123. The breathing valve 127 can also be opened to communicate with the outside atmosphere when the air pressure in the storage chamber 123 is lower than the minimum air pressure in the preset air pressure range to inhale part of the outside air.

[0041] Please refer to Figure 4 It is worth noting that a reaction chamber 131 is provided in the exhaust pipe 130, and the exhaust pipe 130 has an outlet 132, and the reaction chamber 131 is provided between the injection pipe 140 and the outlet 132. After the urea solution sprayed from the injection pipe 140 is mixed with the exhaust gas in the exhaust pipe 130, it enters the reaction chamber 131 under the action of the wind force of the exhaust gas, and performs a catalytic reduction reaction in the reaction chamber 131, thereby realizing the post-treatment operation.

[0042] In this embodiment, the evaporation chamber 110 is in a hollow column shape, and the evaporation chamber 110 is sleeved outside the exhaust pipe 130 to increase the contact area between the evaporation chamber 110 and the exhaust pipe 130, thereby improving the heat transfer efficiency, so that the heat of the high-temperature exhaust gas in the exhaust pipe 130 can be quickly transferred to the evaporation chamber 110 through the exhaust pipe 130, and the gasification efficiency of the phase change medium is improved. Specifically, the evaporation chamber 110 is arranged close to the engine 300, and the high-temperature exhaust gas generated by the engine 300 passes through the evaporation chamber 110 at the first time after the engine 300 is started, so that the phase change medium can be gasified at the first time when the engine 300 is started, so that the urea solution in the urea cavity 220 can be sprayed out of the injection pipe 140 at the first time when the engine 300 is started, and the high-temperature exhaust gas is post-processed.

[0043] In this embodiment, the phase change medium is water, and the temperature of the high-temperature exhaust gas ejected by the engine 300 is generally about 200 degrees Celsius. The phase change medium can be gasified and expanded through the evaporation chamber 110 at the first time of ejection, so that the phase change medium pushes the piston 122 to move, thereby pressing the urea solution in the urea cavity 220 out of the injection pipe 140. However, it is not limited to this. In other embodiments, the phase change medium can also be alcohol or acetone. The material of the phase change medium is not specifically limited. Any phase change medium with a boiling point higher than the ambient temperature and lower than the temperature of the high-temperature exhaust gas is within the protection scope of the present invention.

[0044] In this embodiment, the engine post-treatment device 100 is applied to an area with a relatively high ambient temperature, and the urea solution will not crystallize due to the low temperature. In addition, when the volume of the urea cavity 220 reaches the maximum, the volume of the urea solution stored therein can meet the urea solution demand of the engine 300 for the longest continuous working time, which can be 1 day or 2 days, and the longest continuous working time of the engine 300 is not specifically limited.

[0045] It should be noted that when the engine 300 is started, the engine 300 outputs high-temperature exhaust gas into the exhaust pipe 130. The high-temperature exhaust gas transfers heat to the evaporation chamber 110 through the exhaust pipe 130, so that the phase change medium in the evaporation chamber 110 is vaporized and expanded, and the air pressure in the pressure cavity 210 increases, pushing the piston 122 to slide downward to press the urea solution in the urea cavity 220 into the injection pipe 140, so that the pressure in the injection pipe 140 increases to a preset pressure. At this time, the pressure sensor 180 sends a first control signal to the controller 200, and when the high-temperature exhaust gas passes through the temperature sensor 170, the temperature sensor 170 sends a second control signal to the controller 200. When the controller 200 receives the first control signal and the second control signal, it controls the regulating valve 190 to open, so that the urea solution in the injection pipe 140 passes through the second one-way valve 150, the urea filter element 160 and the regulating valve 190, and is injected into the exhaust pipe 130, thereby performing a catalytic reduction reaction with the high-temperature exhaust gas in the exhaust pipe 130 to achieve post-processing operations.

[0046] When the engine 300 is shut down, the engine 300 no longer outputs high-temperature exhaust gas to the exhaust pipe 130, and the heat of the evaporation chamber 110 is gradually dissipated into the outside air. The phase change medium in the evaporation chamber 110 liquefies and shrinks, the air pressure in the pressure cavity 210 decreases, and the adsorption piston 122 slides upward. In this process, due to the decrease in temperature in the exhaust pipe 130, the temperature sensor 170 no longer sends the second control signal to the controller 200. The controller 200 controls the regulating valve 190 to close, and the volume of the urea cavity 220 gradually increases. Under the action of the pressure difference, the urea solution in the storage chamber 123 is sucked into the urea cavity 220 through the suction pipe 124 and the first one-way valve 125 installed on the suction pipe 124, thereby realizing the replenishment operation of the urea solution.

[0047] The engine aftertreatment device 100 provided by the embodiment of the present invention comprises a urea tank 120 including a pressure chamber 121, a piston 122 movably disposed in the pressure chamber 121, the piston 122 separating the pressure chamber 121 into a pressure cavity 210 and a urea cavity 220, the pressure cavity 210 being communicated with the evaporation chamber 110, the urea cavity 220 being communicated with the exhaust pipe 130, the urea cavity 220 containing a urea solution, the evaporation chamber 110 being arranged in contact with the exhaust pipe 130, a phase change medium being arranged in the evaporation chamber 110, the evaporation chamber 110 being capable of absorbing heat from the exhaust pipe 130 when the engine 300 is started, so as to gasify and expand the phase change medium, thereby pressing the urea solution in the urea cavity 220 into the exhaust pipe 130 through the piston 122. Compared with the prior art, the engine aftertreatment device 100 provided by the present invention can reduce the use of assembly parts because it adopts a phase change medium arranged in the evaporation chamber 110 and a piston 122 movably arranged in the pressure chamber 121, and has a simple and compact structure, small space occupation, low production cost, safety and reliability, and strong practicality.

[0048] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. An engine aftertreatment device, characterized in that: The invention comprises an evaporation chamber (110), a urea tank (120) and an exhaust pipe (130), wherein the urea tank (120) comprises a pressure chamber (121), a piston (122) is movably arranged in the pressure chamber (121), the piston (122) separates the pressure chamber (121) into a pressure cavity (210) and a urea cavity (220), the pressure cavity (210) is communicated with the evaporation chamber (110), and the urea cavity (220) is communicated with the exhaust pipe (130). The urea cavity (220) is connected to the exhaust pipe (130), the urea solution is contained in the urea cavity (220), the evaporation chamber (110) is arranged in contact with the exhaust pipe (130), a phase change medium is arranged in the evaporation chamber (110), and the evaporation chamber (110) can absorb heat from the exhaust pipe (130) when the engine (300) is started, so that the phase change medium is gasified and expanded, thereby pressing the urea solution in the urea cavity (220) into the exhaust pipe (130) through the piston (122).

2. The engine aftertreatment device according to claim 1, characterized in that: The urea tank (120) further comprises a storage chamber (123), wherein the storage chamber (123) is fixedly connected to the pressure chamber (121) and communicates with the urea cavity (220), and the storage chamber (123) is used to store urea solution.

3. The engine aftertreatment device according to claim 2, characterized in that: The urea tank (120) further comprises a liquid suction pipe (124) and a first one-way valve (125); the liquid suction pipe (124) is fixedly connected to the storage chamber (123) and communicates with the urea cavity (220); the first one-way valve (125) is installed on the liquid suction pipe (124); the first one-way valve (125) is used to prevent the urea solution in the urea cavity (220) from flowing into the storage chamber (123).

4. The engine aftertreatment device according to claim 2, characterized in that: The storage chamber (123) is provided with an injection port (126), and the injection port (126) is used to replenish urea solution into the storage chamber (123).

5. The engine aftertreatment device according to claim 2, characterized in that: The storage chamber (123) is provided with a breathing valve (127), and the breathing valve (127) is used to communicate with the outside atmosphere when the air pressure in the storage chamber (123) exceeds or falls below a preset air pressure range, so as to prevent the storage chamber (123) from being damaged.

6. The engine aftertreatment device according to any one of claims 1 to 5, characterized in that: The engine aftertreatment device further comprises an injection pipe (140) and a second one-way valve (150); one end of the injection pipe (140) is communicated with the urea cavity (220), and the other end is communicated with the exhaust pipe (130); the second one-way valve (150) is installed on the injection pipe (140); the second one-way valve (150) is used to prevent the urea solution in the exhaust pipe (130) from flowing into the urea cavity (220).

7. The engine aftertreatment device according to claim 6, characterized in that: The engine aftertreatment device further comprises a urea filter element (160), wherein the urea filter element (160) is mounted on the injection pipe (140), and the urea filter element (160) is used to filter a urea solution.

8. The engine aftertreatment device according to claim 6, characterized in that: The engine aftertreatment device further comprises a temperature sensor (170), a pressure sensor (180), a regulating valve (190) and a controller (200). The temperature sensor (170) is installed in the exhaust pipe (130), the pressure sensor (180) and the regulating valve (190) are both installed in the injection pipe (140), the temperature sensor (170), the pressure sensor (180) and the regulating valve (190) are all connected to the controller (200), the temperature sensor (170) is used to send a first control signal to the controller (200) when it is detected that the temperature in the exhaust pipe (130) reaches a preset temperature, the pressure sensor (180) is used to send a second control signal to the controller (200) when it is detected that the pressure in the injection pipe (140) reaches a preset pressure, and the controller (200) is used to control the regulating valve (190) to open when the first control signal and the second control signal are received at the same time.

9. The engine aftertreatment device according to claim 6, characterized in that: A reaction chamber (131) is arranged in the exhaust pipe (130), the exhaust pipe (130) has a gas outlet (132), and the reaction chamber (131) is arranged between the injection pipe (140) and the gas outlet (132).

10. The engine aftertreatment device according to claim 1, characterized in that: The evaporation chamber (110) is in the shape of a hollow column, and the evaporation chamber (110) is sleeved outside the exhaust pipe (130).

Images