Automobile exhaust system ammonia mixing test equipment and test method

Abstract

The invention relates to the field of vehicle testing, in particular to ammonia mixing testing equipment and a testing method for an automobile exhaust system. The ammonia mixing test equipment is used for carrying out ammonia mixing test on the catalyst, the catalyst is provided with a gas inlet and a gas outlet, and the ammonia mixing test equipment comprises a gas taking device, a gas conveying device, a gas detection mechanism and a base; the gas taking device comprises a mounting frame, a mounting assembly arranged on the mounting frame, a plurality of gas taking pipes evenly distributed around the mounting assembly and an adjusting assembly arranged on the mounting frame and used for adjusting the distance between the gas taking pipes, and gas inlet heads are arranged at the front ends of the gas taking pipes. The gas conveying device comprises a ventilation disc with a plurality of gas guiding channels in the periphery, a communicating disc with a gas channel, a first motor used for driving the communicating disc to rotate, a communicating pipe communicating with the gas guiding channels in a sliding and sealing mode in the radial direction, and a gas guiding pipe communicating with a gas channel outlet in a rotating and sealing mode. A supporting seat and a transverse moving mechanism are arranged on the base. According to the invention, multi-point ammonia mixing detection can be carried out on the inner side of the catalyst so as to obtain more detailed ammonia mixing distribution data.

Description

Technical Field

[0001] The invention relates to the field of vehicle testing, and in particular to an ammonia mixing testing device and a testing method for an automobile exhaust system. Background Art

[0002] For SCR (Selective Catalytic Reduction) catalysts, the vehicle's urea injection system injects urea aqueous solution into the exhaust pipe. The urea aqueous solution is pyrolyzed and hydrolyzed in the exhaust to form ammonia, which reacts with NOx (nitrogen oxides) in the exhaust gas to generate harmless nitrogen and water, thereby reducing NOx in the exhaust gas. There is an important evaluation parameter in the SCR catalyst - ammonia distribution (ammonia mixing). Uneven ammonia mixing will seriously affect the performance of the product.

[0003] Chinese patent announcement number CN114235435B discloses an ammonia mixing test device for automobile exhaust system, including: a flexible base, an air extraction pipe, a synchronous connecting rod, a motor base, a servo motor, a guide optical axis and a gas detection mechanism. The same group of air extraction pipes for the air inlet and the air outlet of the catalyst to be tested can realize simultaneous air extraction under one exhaust operation, and the catalyst to be tested has no structural damage except for the installation of the air extraction part, and has good measurement effect, high measurement accuracy, and greatly improved measurement efficiency.

[0004] However, the above scheme has the following shortcomings: air sampling detection can only be performed at the air inlet and outlet of the catalyst, and air sampling detection cannot be performed at different points inside the catalyst, which makes it difficult to obtain more detailed ammonia mixing distribution test data. Summary of the invention

[0005] The purpose of the present invention is to address the problems existing in the background technology and to propose an automobile exhaust system ammonia mixing test device and a test method that can perform multi-point ammonia mixing detection on the inner side of the catalyst to obtain more detailed ammonia mixing distribution data.

[0006] On the one hand, the present invention provides an ammonia mixing test device for an automobile exhaust system, which is used to perform an ammonia mixing test on a catalyst. The catalyst has an air inlet and an exhaust port. The ammonia mixing test device includes an air intake device, a gas delivery device, a gas detection mechanism and a base. The air intake device includes a mounting frame, a mounting assembly arranged on the mounting frame, a plurality of air intake pipes evenly distributed around the mounting assembly, and an adjustment assembly arranged on the mounting frame and adjusting the spacing between the plurality of air intake pipes. The front end of the air intake pipe has an air intake head. The gas delivery device includes a vent plate with a plurality of air inlet channels evenly distributed around a central axis and arranged radially on the outer periphery, a rotary seal arranged on the vent plate and A connecting plate with an airway, a first motor for driving the connecting plate to rotate, a connecting pipe connected to the air inlet channel along a radial sliding seal, and an air inlet pipe connected to the airway outlet by a rotating seal, the air plate and the first motor are both arranged on a mounting frame, the airway outlet is located in the middle of the connecting plate, the airway inlet is located on the circumferential surface of the connecting plate, the connecting pipe is connected to the air intake pipe, and when the connecting plate rotates, the airway connects the air intake pipe to one of the multiple connecting pipes; a gas detection mechanism is connected to the air intake pipe; a support seat for supporting the catalyst is provided on the base, and a transverse movement mechanism for driving the mounting frame to move horizontally to adjust the distance by which the air intake pipe extends into the interior of the catalyst.

[0007] Preferably, the mounting assembly includes a connecting frame arranged on the mounting frame, a plurality of slide rails evenly distributed in a ring shape on the connecting frame, a mounting platform arranged on the slide rails, and a slider slidably arranged on the slide rails, and the air extraction pipe is arranged on the slider.

[0008] Preferably, a cross bar is provided at the front of the mounting platform, a guide platform is provided at the front end of the cross bar, the guide platform is located between multiple air intake pipes, the guide platform has a conical guide surface, the top of the conical guide surface is located on the side away from the cross bar, and the conical guide surface is concave inward.

[0009] Preferably, the adjustment component includes a second motor arranged on a mounting frame, a first screw rod rotatably arranged on the mounting frame and connected to the output end of the second motor, a movable seat threadedly connected to the first screw rod, and a plurality of connecting components evenly distributed around the movable seat, the connecting component includes a rotating sleeve arranged on the air extraction pipe and a connecting rod whose two ends are respectively rotatably connected to the rotating sleeve and the movable seat.

[0010] Preferably, the air intake pipe includes a first straight pipe portion, an inclined pipe portion and a second straight pipe portion that are integrally connected, the first straight pipe portion and the second straight pipe portion are parallel, and the air inlet head is located at the outer end of the first straight pipe portion; the connecting pipe includes a right-angle pipe portion, a third straight pipe portion, a fourth straight pipe portion and a fifth straight pipe portion that are integrally connected, the second straight pipe portion is connected to the right-angle pipe portion in a rotating seal, and the fifth straight pipe portion is connected to the air inlet channel of the ventilation disk in a sliding seal.

[0011] Preferably, the second straight tube portion of the air extraction pipe is rotatably arranged on the slider and the rotating sleeve, the second straight tube portion is provided with a first gear, the mounting assembly is provided with a limiting assembly for limiting and releasing the limiting of the first gear, a third motor is arranged on the mounting platform, and the third motor drives and is connected to the second gear. When the multiple air extraction pipes are retracted to the extreme position, the first gear is meshed with the second gear, and the limiting assembly releases the limiting of the first gear.

[0012] Preferably, the limiting assembly includes a stopper arranged on the mounting platform, a fixed plate arranged on the sliding block, a sliding column slidably arranged on the fixed plate, a movable frame and a connecting platform respectively connected to both ends of the sliding column, a rack arranged on the movable frame and facing the first gear, and a spring sleeved on the sliding column and connected to the fixed plate and the connecting platform at both ends respectively, and the connecting platform faces the stopper.

[0013] Preferably, the transverse movement mechanism includes a second screw rod horizontally rotatably arranged on the base, a guide rod parallel to the second screw rod and arranged on the base, a fourth motor arranged on the base and drivingly connected to the second screw rod, a support frame arranged at the bottom of the mounting frame, and a movable platform arranged at the bottom of the support frame, the movable platform being slidably arranged on the guide rod and threadedly connected to the second screw rod.

[0014] Preferably, the air duct is connected to an exhaust pipe, a control valve is provided on the exhaust pipe, the exhaust pipe is connected to an exhaust pump, a plurality of ventilation pipes are evenly connected to the periphery of the ventilation plate, the plurality of ventilation pipes are spaced apart from the plurality of air ducts, and a filter is provided at the ventilation pipe.

[0015] On the other hand, the present invention provides a method for testing ammonia mixing in an automobile exhaust system, which is implemented by the above-mentioned automobile exhaust system ammonia mixing testing device, and the testing method comprises the following steps: S1. Place the catalyst to be tested on the support; S2, start the second motor, the second motor drives the first screw to rotate, and the multiple sets of connecting components drive the multiple air intake pipes to close to the position where the first gear and the second gear are meshed. At this time, the rack is disengaged from the first gear; S3, starting the third motor, the third motor drives the second gear to rotate, the second gear drives the air intake pipe to rotate through the first gear, and the first straight pipe parts of the multiple air intake pipes are rotated inward to reduce the distance between the multiple air intake heads; S4, driving the mounting frame to move horizontally through the lateral movement mechanism, extending the plurality of air intake heads from the exhaust port of the catalyst into the interior of the catalyst until the air intake heads move to one side of the air intake port; S5. The gas to be tested is continuously introduced into the air inlet of the catalyst, and the catalyst is activated synchronously; S6. The connecting disk is driven to rotate by the first motor, and the air passage connects the air duct to one of the multiple connecting tubes. Each time one of the multiple connecting tubes is connected, the air inlet head on the air intake pipe corresponding to the connecting tube introduces the gas into the air intake pipe. The air intake pipe transports the gas to the gas detection mechanism through the connecting tube, the ventilation disk, the connecting disk and the air duct. The gas detection mechanism sequentially performs ammonia mixing detection on the gas introduced by the multiple air inlet heads. S7, start the second motor, the second motor intermittently drives the first screw to rotate in the opposite direction, the first gear disengages from the second gear, the rack is clamped on the first gear to limit the position, the gas pipe intermittently moves outward, and step S6 is performed in each intermittent time period when the outward movement stops, and the gas detection mechanism performs ammonia mixing detection on the gas introduced by multiple gas inlet heads in turn; S8, re-engage the first gear with the second gear, start the third motor, adjust the distribution position of the gas inlet head at the front end of the gas intake pipe, and then re-perform steps S6-S7, and the gas detection mechanism performs ammonia mixing detection on the gas introduced by the multiple gas inlet heads in turn; S9, intermittently drive the mounting frame to move away from the exhaust port of the catalyst through the transverse movement mechanism, and perform step S8 in each intermittent time period when the transverse movement is stopped, thereby achieving the purpose of multi-point ammonia mixing detection on the inner side of the catalyst.

[0016] Compared with the prior art, the present invention has the following beneficial technical effects: The present invention can perform ammonia mixing detection at multiple points inside the catalyst, thereby obtaining more detailed ammonia mixing distribution data. The distribution position of the intake head can be adjusted, and the gas detection mechanism only performs ammonia mixing detection on the gas introduced by one intake head at a time. In general, the gas detection mechanism is used to detect the gas introduced at more points to obtain more detailed ammonia mixing distribution data. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a structural schematic diagram of an embodiment of the present invention; Figure 2 A partial structural cross-sectional view of an embodiment of the present invention; Figure 3 A cross-sectional view of the principle structure for adjusting the position of the air intake pipe; Figure 4 for Figure 3 A magnified view of the structure at center A; Figure 5 A schematic diagram of a structure for adjusting a plurality of air intake pipes to another distribution state; Figure 6 A schematic diagram of a structure for clamping a catalyst.

[0018] Reference numerals: 100, catalyst; 1, base; 2, support seat; 3, mounting frame; 4, connecting frame; 5, slide rail; 6, mounting platform; 7, slider; 8, air intake pipe; 81, air intake head; 9, connecting pipe; 10, ventilation plate; 11, connecting plate; 111, air duct; 12, air duct; 13, ventilation pipe; 14, first motor; 15, first gear; 16, fixing plate; 17, sliding column; 171, spring; 18, moving frame; 19. Rack; 20. Connecting platform; 21. Stop platform; 22. Rotating sleeve; 23. Connecting rod; 24. Moving seat; 25. Second motor; 26. First screw rod; 27. Second gear; 28. Third motor; 29. ​​Cross bar; 30. Guide platform; 31. Support frame; 32. Moving platform; 33. Fourth motor; 34. Second screw rod; 35. Guide rod; 36. Fixed seat; 37. Threaded knob; 38. Sliding rod; 39. Clamp. DETAILED DESCRIPTION

[0019] Embodiment 1, as Figure 1-Figure 6 As shown, the present embodiment provides an ammonia mixing test device for automobile exhaust system, which is used to perform an ammonia mixing test on a catalyst 100. The catalyst 100 has an air inlet and an exhaust port. The ammonia mixing test device includes an air intake device, a gas delivery device, a gas detection mechanism and a base 1. The air intake device extends into the inner side of the catalyst 100, and delivers the gas to the gas detection mechanism through the gas delivery device for ammonia mixing detection.

[0020] like Figure 2-Figure 5 As shown, the gas extraction device includes a mounting frame 3, a mounting assembly arranged on the mounting frame 3, a plurality of gas extraction pipes 8 evenly distributed around the mounting assembly, and an adjusting assembly arranged on the mounting frame 3 and adjusting the spacing between the plurality of gas extraction pipes 8. The front end of the gas extraction pipe 8 has an air inlet head 81. The air inlet head 81 faces the direction of the incoming gas, and the gas can be directly blown into the air inlet head 81, and then flow along the gas extraction pipe 8, and finally flow into the gas detection mechanism. By adjusting the spacing between the plurality of gas extraction pipes 8 through the adjusting assembly, the radial position of the plurality of gas extraction pipes 8 distributed circumferentially can be adjusted, so that the air inlet head 81 can extract gas at multiple points, thereby expanding the gas extraction range.

[0021] like Figure 3As shown, the air delivery device includes a vent disc 10 having a plurality of air bleed channels evenly distributed around a central axis and arranged radially, a connecting disc 11 having an air channel 111 and being rotatably sealed and arranged on the vent disc 10, a first motor 14 for driving the connecting disc 11 to rotate, a connecting pipe 9 connected to the air bleed channel in a radially sliding seal, and an air bleed pipe 12 connected to the outlet of the air channel 111 by a rotatable seal. When the first motor 14 drives the connecting disc 11 to rotate, the air channel 111 can be connected to air bleed channels in different directions, and the air channel 111 maintains communication with the air bleed pipe 12. The vent disc 10 and the first motor 14 are both arranged on the mounting frame 3, and the outlet of the air channel 111 is located in the middle of the connecting disc 11, and the connection with the air bleed pipe 12 is not affected when the connecting disc 11 rotates. The inlet of the air channel 111 is located on the circumferential surface of the connecting disc 11, and when the inlet of the air channel 111 faces an air bleed channel, it is connected to the air bleed channel. The connecting tube 9 is connected with the air intake tube 8. When the air intake tube 8 moves, the connecting tube 9 slides at the air inlet passage, but remains connected and does not interfere with the movement of the air intake tube 8. When the connecting disk 11 rotates, the air passage 111 connects the air inlet tube 12 with one of the multiple connecting tubes 9, that is, the air passage 111 can only be connected with one air inlet passage on the ventilation disk 10 at a time, and connects the connecting tube 9 with the air inlet tube 12 through the air inlet passage and the air passage 111, so as to realize the air supply to the gas detection mechanism.

[0022] The gas detection mechanism is connected to the air bleed pipe 12 to detect ammonia mixing in the gas delivered from the air intake head 81 , the air intake pipe 8 , the connecting pipe 9 , the air bleed channel of the ventilation disk 10 , the air passage 111 of the connecting disk 11 and the air bleed pipe 12 .

[0023] like Figure 1 and Figure 5 As shown, the base 1 is provided with a support base 2 for supporting the catalyst 100 and a transverse movement mechanism for driving the mounting frame 3 to move horizontally to adjust the distance of the gas intake pipe 8 extending into the interior of the catalyst 100. The transverse movement mechanism adjusts the insertion depth of the gas intake pipe 8 by adjusting the horizontal position of the mounting frame 3, so as to introduce the gas to be detected at different positions using the gas intake head 81.

[0024] like Figure 1 As shown, the transverse movement mechanism includes a second screw rod 34 horizontally rotatably arranged on the base 1, a guide rod 35 parallel to the second screw rod 34 and arranged on the base 1, a fourth motor 33 arranged on the base 1 and drivingly connected to the second screw rod 34, a support frame 31 arranged at the bottom of the mounting frame 3, and a moving platform 32 arranged at the bottom of the support frame 31, and the moving platform 32 is slidably arranged on the guide rod 35 and threadedly connected to the second screw rod 34. The fourth motor 33 can drive the second screw rod 34 to rotate forward and reversely, and the second screw rod 34 drives the moving platform 32 to move, and the guide rod 35 guides the moving platform 32 to move horizontally, and the moving platform 32 drives the mounting frame 3 to move horizontally through the support frame 31, and the moving process is smooth.

[0025] Furthermore, a structure is added to improve the position stability of the catalyst 100, such as Figure 1 and Figure 6 As shown, the top of the support base 2 has a supporting groove that matches the contour of the lower part of the catalyst 100. Two sets of clamping components are symmetrically arranged on the support base 2, which can be clamped from both sides of the catalyst 100 to ensure stability during the ammonia mixing test. Figure 6 As shown, the clamping assembly includes a fixed seat 36 arranged at the outer end of the support seat 2, a threaded knob 37 that is horizontally distributed and threadedly connected to the fixed seat 36, a slide bar 38 that is parallel to the threaded knob 37 and slidably arranged on the fixed seat 36, and a clamping plate 39 connected to the end of the slide bar 38, and the clamping plate 39 is rotatably connected to the end of the threaded knob 37. By rotating the threaded knob 37, the threaded knob 37 can be moved on the fixed seat 36, and the clamping plate 39 is driven to move. The slide bar 38 slides on the fixed seat 36 to guide the movement of the clamping plate 39. The threaded connection between the threaded knob 37 and the fixed seat 36 is self-locking, which ensures the stability of the clamping plates 39 on both sides when clamping.

[0026] like Figure 2 and Figure 5 As shown, the mounting assembly includes a connecting frame 4 arranged on the mounting frame 3, a plurality of slide rails 5 evenly distributed in a ring shape on the connecting frame 4, a mounting platform 6 arranged on the slide rail 5, and a slider 7 slidably arranged on the slide rail 5, and an air extraction pipe 8 is arranged on the slider 7. The slider 7 can slide on the slide rail 5, and the plurality of sliders 7 can synchronously move toward the mounting platform 6 in the middle or synchronously move away from each other, so as to drive the plurality of air extraction pipes 8 to synchronously gather or spread, so as to achieve the purpose of adjusting the spacing between the plurality of air extraction pipes 8.

[0027] A cross bar 29 is provided at the front of the mounting platform 6, and a guide platform 30 is provided at the front end of the cross bar 29. The guide platform 30 is located between the multiple air intake pipes 8 and is shielded in front of other structures at the rear side. The guide platform 30 has a conical guide surface, the top of which is located on the side away from the cross bar 29, and the conical guide surface is concave inward. When the gas is discharged from the exhaust port of the catalyst 100, it is guided by the conical guide surface of the guide platform 30 and directed to the periphery to prevent affecting other structures at the rear side.

[0028] like Figure 3 and Figure 4As shown, the adjustment assembly includes a second motor 25 arranged on the mounting frame 3, a first screw rod 26 rotatably arranged on the mounting frame 3 and connected to the output end of the second motor 25, a moving seat 24 threadedly connected to the first screw rod 26, and multiple groups of connection assemblies evenly distributed around the moving seat 24. The second motor 25 can drive the first screw rod 26 to rotate forward and reversely to drive the moving seat 24 to reciprocate. The connection assembly includes a rotating sleeve 22 arranged on the air extraction pipe 8 and a connecting rod 23 rotatably connected to the rotating sleeve 22 and the moving seat 24 at both ends. The moving seat 24 can drive the rotating sleeve 22 to move through the connecting rod 23, and the rotating sleeve 22 drives the air extraction pipe 8 to move. Multiple groups of connection assemblies are evenly distributed, so that multiple air extraction pipes 8 can be driven to move inward or outward synchronously.

[0029] This embodiment can perform multi-point ammonia mixing detection on the inside of the catalyst 100, so as to obtain more detailed ammonia mixing distribution data. The gas to be tested is continuously introduced into the air inlet of the catalyst 100, and the radial position of the multiple air intake pipes 8 is adjusted by the adjustment component, so that the air intake head 81 can take air at multiple points and expand the air intake range; and the lateral position of the mounting frame 3 is intermittently adjusted in the direction from the air inlet of the catalyst 100 to the exhaust port, so that more points of air can be taken through the air intake head 81 at different distances where the air intake pipe 8 extends into the catalyst 100. The gas detection mechanism is used to detect the gas introduced at more points to obtain more detailed ammonia mixing distribution data.

[0030] Embodiment 2, as Figure 1-Figure 6 As shown, this embodiment proposes an ammonia mixing test equipment for automobile exhaust system. Compared with the first embodiment, in this embodiment, the air intake pipe 8 includes a first straight pipe part, an oblique pipe part and a second straight pipe part that are connected in one piece. The first straight pipe part and the second straight pipe part are parallel. The air intake head 81 is located at the outer end of the first straight pipe part, which can effectively introduce gas. The connecting pipe 9 includes a right-angle pipe part, a third straight pipe part, a fourth straight pipe part and a fifth straight pipe part that are connected in one piece. The second straight pipe part is connected to the right-angle pipe part in a rotating seal, and the fifth straight pipe part is connected to the air inlet channel of the vent plate 10 in a sliding seal. When the air intake pipe 8 moves, it can drive the connecting pipe 9 to move, and the connecting pipe 9 maintains communication with the air inlet channel.

[0031] The second straight tube portion of the air extraction pipe 8 is rotatably arranged on the slider 7 and the rotating sleeve 22. When adjusting the spacing between the multiple air extraction pipes 8, the rotating sleeve 22 can still drive the air extraction pipe 8 to move. A first gear 15 is arranged on the second straight tube portion. A limiting assembly for limiting and releasing the limiting of the first gear 15 is arranged on the mounting assembly, and each first gear 15 corresponds to a set of limiting assemblies. A third motor 28 is arranged on the mounting platform 6. The third motor 28 is driven and connected to the second gear 27. When the multiple air extraction pipes 8 are retracted to the extreme position, the first gear 15 is meshed with the second gear 27, and the limiting assembly releases the limiting of the first gear 15, so that the third motor 28 can drive the first gear 15 to rotate by driving the second gear 27, and the first gear 15 drives the second straight tube portion of the air extraction pipe 8 to rotate. The first straight tube portion and the second straight tube portion are staggered, and the first straight tube portion rotates around the second straight tube portion, thereby driving the intake head 81 to rotate, adjusting the distribution orientation of the intake head 81, and then guiding gas at different orientations in the catalyst 100, thereby expanding the point distribution range of the gas guiding, and expanding the point range of the gas detection mechanism for detecting ammonia mixing.

[0032] The limiting assembly includes a stopper 21 disposed on the mounting platform 6, a fixed plate 16 disposed on the slider 7, a sliding column 17 slidably disposed on the fixed plate 16, a moving frame 18 and a connecting platform 20 respectively connected to both ends of the sliding column 17, a rack 19 disposed on the moving frame 18 and facing the first gear 15, and a spring 171 sleeved on the sliding column 17 and connected to the fixed plate 16 and the connecting platform 20 at both ends, and the connecting platform 20 faces the stopper 21. When the first gear 15 is not meshed with the second gear 27, the spring 171 pushes the connecting platform 20 to the limit position, the moving frame 18 abuts against the fixed plate 16, and the rack 19 is clamped on the first gear 15 for limiting, thereby preventing the air intake pipe 8 from rotating. When the orientation of the air intake head 81 needs to be adjusted, the multiple air intake pipes 8 are adjusted inwardly through the adjustment assembly, the air intake pipe 8 drives the first gear 15 to move, and drives the fixed plate 16 to move inwardly through the slider 7, and the connecting platform 20 moves toward the stopper 21. When the connecting platform 20 moves to abut against the stopper 21, it continues to move, the fixed plate 16 slides on the slide column 17, and the spring 171 is further compressed between the fixed plate 16 and the connecting platform 20. The first gear 15 is disengaged from the rack 19 and meshes with the second gear 27. At this time, the second gear 27 can be driven to rotate by the third motor 28 to drive the first gear 15 to rotate, thereby adjusting the orientation of the air intake head 81 at the front end of the air intake pipe 8. The catalyst 100 is narrow at both ends and wide in the middle. When the first straight pipe part of the air intake pipe 8 rotates outward relative to the second straight pipe part, the air intake head 81 can rotate to a wider position inside the catalyst 100 for air guide.

[0033] After the azimuth adjustment is completed, the multiple air intake pipes 8 are adjusted outward through the adjustment assembly, the first gear 15 is separated from the second gear 27, and the first gear 15 is again limited by the rack 19. When the air intake pipe 8 is subjected to the pressure of the air flow, the air intake pipe 8 has a tendency to drive the first gear 15 to rotate, but it is not enough to overcome the friction between the sliding column 17 and the fixing plate 16. Therefore, when the rack 19 is clamped on the first gear 15, the first gear 15 will not push the rack 19 outward, and the first gear 15 can be effectively limited.

[0034] The test method of the above-mentioned automobile exhaust system ammonia mixing test equipment comprises the following steps: S1, placing the catalyst 100 to be tested on the support 2; S2, start the second motor 25, the second motor 25 drives the first screw rod 26 to rotate, and the multiple sets of connecting components drive the multiple air intake pipes 8 to close to the position where the first gear 15 and the second gear 27 are meshed. At this time, the rack 19 is separated from the first gear 15, and the second motor 25 can drive the first screw rod 26 to rotate forward and reverse; S3, start the third motor 28, the third motor 28 drives the second gear 27 to rotate, the second gear 27 drives the air intake pipe 8 to rotate through the first gear 15, and the first straight pipe parts of the plurality of air intake pipes 8 are rotated inward, so as to reduce the distance between the plurality of air intake heads 81, and bring the plurality of air intake heads 81 together, so as to facilitate the plurality of air intake pipes 8 to extend from the narrow exhaust port of the catalyst 100; S4, driving the mounting frame 3 to move horizontally through the lateral movement mechanism, and extending the plurality of air intake heads 81 from the exhaust port of the catalyst 100 into the interior of the catalyst 100 until the air intake heads 81 move to one side of the air intake port; S5, continuously introducing the gas to be tested from the air inlet of the catalyst 100, and the catalyst 100 is activated synchronously, and waits for a preset period of time for the gas to be evenly introduced and the catalyst 100 to stabilize; S6. The connecting disk 11 is driven to rotate by the first motor 14, and the air passage 111 connects the air duct 12 with one of the multiple connecting tubes 9. Each time one of the connecting tubes 9 is connected, the air inlet head 81 on the air intake pipe 8 corresponding to the connecting tube 9 introduces the gas into the air intake pipe 8, and the air intake pipe 8 transports the gas to the gas detection mechanism through the connecting tube 9, the ventilation disk 10, the connecting disk 11 and the air intake pipe 12; when one connecting tube 9 is connected with the air passage 111 and the air intake pipe 12, the other connecting tubes 9 are not connected with the air passage 111 or the air intake pipe 12, and gas can only be introduced from one air inlet head 81 at a time; the air passage 111 rotates through the rotation of the connecting disk 11, and switches to connect with the multiple connecting tubes 9 in turn, and the gas detection mechanism performs ammonia mixing detection on the gas introduced by the multiple air inlet heads 81 in turn; S7, start the second motor 25, the second motor 25 intermittently drives the first screw 26 to rotate in the opposite direction, the first gear 15 disengages from the second gear 27, the rack 19 is clamped on the first gear 15 for limiting, the gas pipe 8 intermittently moves outward, the outward movement distance is preset, and step S6 is performed in each intermittent time period when the outward movement stops, the gas detection mechanism sequentially performs ammonia mixing detection on the gas introduced by the multiple gas inlet heads 81, and the number of detection points is further expanded on the basis of the detection points in step S6; S8, re-engage the first gear 15 with the second gear 27, start the third motor 28, adjust the distribution position of the gas inlet head 81 at the front end of the gas intake pipe 8, that is, adjust the distribution orientation of the gas inlet head 81 relative to the second straight pipe portion, and then re-perform steps S6-S7, the gas detection mechanism sequentially performs ammonia mixing detection on the gas introduced by the multiple gas inlet heads 81, and performs gas detection at more points; S9, intermittently drive the mounting frame 3 to move away from the exhaust port of the catalyst 100 through the transverse movement mechanism, and perform step S8 in each intermittent time period when the transverse movement is stopped, so that gas can be introduced at different distances when the air intake head 81 extends into the interior of the catalyst 100, and the ammonia mixing data is detected by the gas detection mechanism, thereby achieving the purpose of multi-point ammonia mixing detection inside the catalyst 100. When the air intake head 81 needs to be removed from the catalyst 100, the multiple air intake pipes 8 are gathered in advance to reduce the distance between the multiple air intake heads 81, so that the air intake pipes 8 and the air intake head 81 can be removed from the exhaust port of the catalyst 100 to avoid interference.

[0035] In the present embodiment, the air intake head 81 can rotate around the second straight pipe portion of the air intake pipe 8, and the air intake head 81 can also move in a straight line toward the inner wall of the catalyst 100, and move in the direction from the air inlet to the exhaust port of the catalyst 100, which greatly increases the number of detection points. The points are densely distributed, and the use of a gas detection mechanism to detect ammonia mixing data can reflect the ammonia mixing distribution in more detail.

[0036] Embodiment three, as Figure 1-Figure 6As shown, the present embodiment proposes an ammonia mixing test equipment for automobile exhaust system. Compared with the first embodiment, in the present embodiment, the air duct 12 is connected with an exhaust pipe, and the exhaust pipe can be specifically connected to the middle of the air duct 12. A control valve is arranged on the exhaust pipe, and the exhaust pipe is connected with an exhaust pump. The outer periphery of the ventilation plate 10 is evenly connected with a plurality of ventilation pipes 13, and the plurality of ventilation pipes 13 are spaced apart from the plurality of air duct channels on the ventilation plate 10, and a filter is arranged at the ventilation pipe 13. When the gas detection mechanism detects the gas transported by the air duct 12, the control valve on the exhaust pipe is closed. When the connecting plate 11 rotates to the point where the air passage 111 is connected to the air duct 13, the rotation is stopped, the control valve is opened, and the exhaust pump is started. After being filtered by the filter, the outside air can enter the air duct 12 through the ventilation pipe 13 and the air passage 111, and the residual gas in the air duct 12 can be discharged from the exhaust pump through the exhaust pipe. Then close the control valve, and rotate the connecting disk 11 to the position where the airway 111 is connected to the connecting pipe 9. The air inlet head 81 introduces the gas at the corresponding point, and the gas is transported to the gas detection mechanism for detection through the airway 111 and the air duct 12. Before each gas detection, the residual gas from the last gas detection is discharged to ensure the accuracy of the detection result.

[0037] The embodiments of the present invention are described in detail above with reference to the accompanying drawings, but the present invention is not limited thereto, and various changes can be made within the knowledge scope of technicians in the relevant technical field without departing from the purpose of the present invention.

Claims

1. An ammonia mixing test device for an automobile exhaust system, used for performing an ammonia mixing test on a catalyst (100), the catalyst (100) having an air inlet and an exhaust port, characterized in that: include: An air extraction device, comprising a mounting frame (3), a mounting assembly arranged on the mounting frame (3), a plurality of air extraction pipes (8) evenly distributed around the mounting assembly, and an adjustment assembly arranged on the mounting frame (3) and adjusting the spacing between the plurality of air extraction pipes (8), wherein the front end of the air extraction pipe (8) has an air inlet head (81); A gas transmission device, comprising a venting disk (10) having a plurality of air inlet passages evenly distributed around a central axis and arranged radially, a connecting disk (11) rotatably sealed and arranged on the venting disk (10) and having an air passage (111), a first motor (14) for driving the connecting disk (11) to rotate, a connecting pipe (9) connected to the air inlet passage in a radially sliding seal, and an air inlet pipe (12) connected to the outlet of the air passage (111) by a rotatable seal, the venting disk (10) and the first motor (14) being both arranged on a mounting frame (3), the outlet of the air passage (111) being located in the middle of the connecting disk (11), the inlet of the air passage (111) being located on the circumferential surface of the connecting disk (11), the connecting pipe (9) being connected to an air intake pipe (8), and when the connecting disk (11) rotates, the air passage (111) connects the air inlet pipe (12) to one of the plurality of connecting pipes (9); A gas detection mechanism, which is in communication with the air bleed pipe (12); A base (1) is provided with a support base (2) for supporting a catalyst (100), and a transverse movement mechanism for driving a mounting frame (3) to move horizontally to adjust the distance that an air intake pipe (8) extends into the interior of the catalyst (100).

2. The automobile exhaust system ammonia mixing test equipment according to claim 1, characterized in that: The mounting assembly comprises a connecting frame (4) arranged on the mounting frame (3), a plurality of slide rails (5) evenly distributed in a ring shape on the connecting frame (4), a mounting platform (6) arranged on the slide rails (5), and a slide block (7) slidably arranged on the slide rails (5), wherein the air intake pipe (8) is arranged on the slide block (7).

3. The automobile exhaust system ammonia mixing test equipment according to claim 2, characterized in that: A cross bar (29) is arranged at the front of the mounting platform (6), and a flow guide platform (30) is arranged at the front end of the cross bar (29). The flow guide platform (30) is located between the plurality of air intake pipes (8), and the flow guide platform (30) has a conical flow guide surface, the top of the conical flow guide surface is located on a side away from the cross bar (29), and the conical flow guide surface is concave inwardly.

4. The automobile exhaust system ammonia mixing test equipment according to claim 2, characterized in that: The adjustment component comprises a second motor (25) arranged on a mounting frame (3), a first screw rod (26) rotatably arranged on the mounting frame (3) and connected to an output end of the second motor (25), a movable seat (24) threadedly connected to the first screw rod (26), and a plurality of connection components evenly distributed around the movable seat (24), wherein the connection components comprise a rotating sleeve (22) arranged on the air intake pipe (8) and a connecting rod (23) having two ends rotatably connected to the rotating sleeve (22) and the movable seat (24), respectively.

5. The automobile exhaust system ammonia mixing test equipment according to claim 4, characterized in that: The air intake pipe (8) comprises a first straight pipe portion, an oblique pipe portion and a second straight pipe portion which are connected in an integral manner, the first straight pipe portion and the second straight pipe portion are parallel, and an air intake head (81) is located at the outer end of the first straight pipe portion; the connecting pipe (9) comprises a right-angle pipe portion, a third straight pipe portion, a fourth straight pipe portion and a fifth straight pipe portion which are connected in an integral manner, the second straight pipe portion is connected in a rotationally sealed manner to the right-angle pipe portion, and the fifth straight pipe portion is connected in a slidingly sealed manner to the air inlet channel of the vent plate (10).

6. The automobile exhaust system ammonia mixing test equipment according to claim 5, characterized in that: The second straight tube portion of the air intake pipe (8) is rotatably arranged on the slider (7) and the rotating sleeve (22), the second straight tube portion is provided with a first gear (15), the mounting assembly is provided with a limiting assembly for limiting and releasing the limiting of the first gear (15), the mounting platform (6) is provided with a third motor (28), the third motor (28) is driven and connected to the second gear (27), when the plurality of air intake pipes (8) are retracted to the limit position, the first gear (15) is meshed with the second gear (27), and the limiting assembly releases the limiting of the first gear (15).

7. The automobile exhaust system ammonia mixing test equipment according to claim 6, characterized in that: The limiting assembly comprises a stopper (21) arranged on the mounting platform (6), a fixed plate (16) arranged on the slide block (7), a sliding column (17) slidably arranged on the fixed plate (16), a moving frame (18) and a connecting platform (20) respectively connected to both ends of the sliding column (17), a rack (19) arranged on the moving frame (18) and facing the first gear (15), and a spring (171) sleeved on the sliding column (17) and connected to the fixed plate (16) and the connecting platform (20) at both ends, and the connecting platform (20) faces the stopper (21).

8. The automobile exhaust system ammonia mixing test equipment according to claim 1, characterized in that: The transverse movement mechanism comprises a second screw rod (34) which is horizontally rotatably arranged on the base (1), a guide rod (35) which is parallel to the second screw rod (34) and arranged on the base (1), a fourth motor (33) which is arranged on the base (1) and is drivingly connected to the second screw rod (34), a support frame (31) which is arranged at the bottom of the mounting frame (3), and a moving platform (32) which is arranged at the bottom of the support frame (31), wherein the moving platform (32) is slidably arranged on the guide rod (35) and is threadedly connected to the second screw rod (34).

9. The automobile exhaust system ammonia mixing test equipment according to claim 1, characterized in that: The air duct (12) is connected to an air extraction duct, a control valve is provided on the air extraction duct, and the air extraction duct is connected to an air extraction pump. The outer periphery of the ventilation plate (10) is evenly connected to a plurality of ventilation ducts (13), the plurality of ventilation ducts (13) are spaced apart from the plurality of air duct channels, and a filter is provided at the ventilation duct (13).

10. A method for testing ammonia mixing in an automobile exhaust system, implemented by the automobile exhaust system ammonia mixing testing device according to claim 7, characterized in that: The test method includes the following steps: S1, placing the catalyst to be tested (100) on the support base (2); S2, starting the second motor (25), the second motor (25) drives the first screw rod (26) to rotate, and the plurality of connecting components drive the plurality of air intake pipes (8) to close to a position where the first gear (15) and the second gear (27) are meshed, and at this time, the rack (19) is disengaged from the first gear (15); S3, starting the third motor (28), the third motor (28) drives the second gear (27) to rotate, the second gear (27) drives the air intake pipe (8) to rotate through the first gear (15), and the first straight pipe portions of the plurality of air intake pipes (8) are rotated inwardly, thereby reducing the distance between the plurality of air intake heads (81); S4, driving the mounting frame (3) to move horizontally by means of a transverse movement mechanism, and extending the plurality of air intake heads (81) from the exhaust port of the catalyst (100) into the interior of the catalyst (100) until the air intake heads (81) move to one side of the air intake port; S5, continuously introducing the gas to be tested from the air inlet of the catalyst (100), and the catalyst (100) is simultaneously activated; S6, driving the connecting disk (11) to rotate by means of the first motor (14), the air passage (111) connects the air duct (12) to one of the plurality of connecting tubes (9), each time one of the connecting tubes (9) is connected, the air inlet head (81) on the air intake tube (8) correspondingly connected to the connecting tube (9) introduces gas into the air intake tube (8), the air intake tube (8) conveys the gas to the gas detection mechanism through the connecting tube (9), the ventilation disk (10), the connecting disk (11) and the air duct (12), and the gas detection mechanism sequentially performs ammonia mixing detection on the gas introduced by the plurality of air inlet heads (81); S7, starting the second motor (25), the second motor (25) intermittently drives the first screw (26) to rotate in the opposite direction, the first gear (15) disengages from the second gear (27), the rack (19) is clamped on the first gear (15) to limit the position, the gas pipe (8) intermittently moves outward, and step S6 is performed in each intermittent time period when the outward movement stops, and the gas detection mechanism sequentially performs ammonia mixing detection on the gas introduced by the multiple gas inlet heads (81); S8, re-engaging the first gear (15) with the second gear (27), starting the third motor (28), adjusting the distribution position of the gas inlet head (81) at the front end of the gas intake pipe (8), and then re-performing steps S6-S7, wherein the gas detection mechanism sequentially performs ammonia mixing detection on the gas introduced by the multiple gas inlet heads (81); S9, intermittently driving the mounting frame (3) to move away from the exhaust port of the catalyst (100) through the transverse movement mechanism, and performing step S8 in each intermittent time period when the transverse movement is stopped, thereby achieving the purpose of performing multi-point ammonia mixing detection on the inner side of the catalyst (100).

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