Inlet air volume monitoring device and method

Abstract

The invention relates to the technical field of air volume monitoring, in particular to an inlet air volume monitoring device and a method thereof.The inlet air volume monitoring device comprises a monitoring assembly, the monitoring assembly comprises a supporting ring and a Y-shaped support, ports are correspondingly formed in the center and any supporting arm of the Y-shaped support, and thermal sensors and pitot tubes are correspondingly arranged in the ports; a Venturi tube structure; the ash removal assembly comprises a mounting ring, a first sleeve, a second sleeve, an ash removal unit and an ash collection unit. According to the device, the monitoring sensor can be regularly and automatically subjected to rotary dust removal, the possibility that coal ash dust covers an inlet of the coal mill is reduced, and meanwhile the removed coal ash dust is collected in a gathering mode; the straight pipe section of the coal mill can be partially replaced with the Venturi pipe structure, the defects of the straight pipe section are overcome, the situation that measurement fluctuation exceeds the measurement range is avoided, the multiple measurement points are arranged on the section of the straight pipe section to cover the center and edge areas, and the problem that single-point measurement is interfered by airflow turbulence and dust is solved.

Description

Technical Field

[0001] The present invention relates to the technical field of air volume monitoring, and in particular to a device and method for monitoring inlet air volume. Background Art

[0002] A coal mill is a machine that breaks up coal blocks and grinds them into coal powder. It is an important auxiliary equipment for pulverized coal furnaces. There are vertical grinding mills, high-pressure suspension roller mills, medium-speed micro-powder mills, super-pressure trapezoidal mills, Raymond mills and other models. The coal grinding process is the process of coal being broken up and its surface area continuously increasing. To increase the new surface area, the binding force between solid molecules must be overcome, which requires energy consumption. Coal is ground into coal powder in the coal mill, mainly through three methods: crushing, crushing and grinding.

[0003] Currently, coal mill operations typically install sensors at the mill inlet to monitor airflow. However, the coal ash dust that accumulates at the mill inlet easily adheres to the sensor surface, preventing accurate measurement and affecting the accuracy of the entire airflow monitoring system. Traditional cleaning methods often require the mill to be shut down for cleaning, increasing maintenance costs and equipment downtime.

[0004] The above content is only used to assist in understanding the technical solution of the present invention and does not mean that the above content is the closest prior art. Summary of the Invention

[0005] The purpose of the present invention is to solve the above-mentioned deficiencies and provide a monitoring device and method for inlet air volume.

[0006] In order to solve the above technical problems, the present invention adopts the following technical solutions: an inlet air volume monitoring device includes a monitoring assembly for monitoring the inlet air volume of a coal mill, the monitoring assembly includes a support ring correspondingly arranged on the straight pipe section of the coal mill and a Y-shaped bracket coaxially arranged within the support ring, the center of the Y-shaped bracket and any one of its arms are respectively provided with openings, and the openings are respectively provided with a thermal sensor and a pitot tube;

[0007] The Venturi tube structure is extended and detachably installed on the straight pipe section of the coal mill. It is used to convert the wind speed into a pressure difference signal according to the principles of fluid mechanics, and then calculate the air volume through a calibration formula;

[0008] The ash cleaning assembly includes mounting rings spaced apart in the straight pipe section of the coal mill, a first sleeve arranged in a circular array on the mounting ring and moving radially along the mounting ring, and a second sleeve centrally arranged on the mounting ring. A ash cleaning unit for rotationally cleaning the thermal sensors and the Pitot tubes distributed at corresponding positions is provided in each of the first sleeves and the second sleeve. An ash collecting unit for synchronously collecting the removed coal ash dust during the rotational cleaning process is provided on the end of each of the first sleeves away from the support ring.

[0009] Furthermore, the venturi tube structure includes an inlet section, a contraction section, a throat section and an expansion section arranged in sequence along the airflow direction, and one side of the throat section is provided with a plurality of adjacent pressure holes distributed along the circumferential direction and along the airflow direction;

[0010] The pressure taking hole is used for equalizing the pressure inside the Venturi tube structure.

[0011] Furthermore, the dust cleaning unit includes a cleaning brush eccentrically arranged on one side of each of the first sleeve and the second sleeve, and a first inner gear ring correspondingly arranged at the end of each of the first sleeve and the second sleeve, and the cleaning brush is provided with a first gear meshing with the first inner gear ring;

[0012] The transmission force drives the first sleeve and the second sleeve to rotate synchronously, so that the cleaning brush follows the first sleeve and the second sleeve to revolve and clean dust, and at the same time, the meshing of the first inner ring gear and the first gear drives the cleaning brush to rotate and clean dust.

[0013] Furthermore, the ash collecting unit includes a shell correspondingly arranged on one side of the mounting ring and two blade-shaped rotors arranged in the shell and moving relative to each other through synchronous gear transmission, the outside of the shell is connected to a conduit opposite to the rotation direction of the two blade-shaped rotors, an extension tube is provided on the end of the conduit away from the shell, the outer end of the extension tube is arranged toward the pressure taking hole, a movable ring 1 is provided on a section of the extension tube, the circumference of the movable ring 1 is provided with a hose with the same number as the first sleeve, a negative pressure interface is provided on the end of the hose away from the movable ring 1, and a movable ring 2 rotatably connected to the end of the first sleeve is provided on the negative pressure interface, a discharge pipe is provided on the other end of the shell relative to the conduit, and the outer end of the discharge pipe is connected to the closed dust collecting chamber;

[0014] During the rotation of the two relatively moving blade-shaped rotors distributed inside the shell, the gas at the outer end pipe mouth of the extension pipe and the corresponding hose pipe mouth installed on the extension pipe is sucked in through the conduit until the cleared coal ash dust is sucked into the dust collecting chamber through the exhaust pipe.

[0015] Furthermore, the movable ring 1 is further provided with a hose connected to the second sleeve;

[0016] The hose is used to transport the coal ash dust inside the second sleeve under negative pressure.

[0017] Furthermore, a transmission mechanism is provided on the circumference of the second sleeve for synchronously driving each of the first sleeves to move radially along the mounting ring;

[0018] The transmission mechanism includes a screw rod 1 and a guide rod correspondingly arranged between the mounting ring and the first sleeve, the screw rod 1 and the guide rod being adapted to be provided with an outer ring rotatably connected to the outer end of the movable ring 2, the second sleeve being provided with an internally threaded side plate corresponding to the position of the screw rod 1 and the guide rod, the end surface thread of the internally threaded side plate being adapted to be provided with a screw rod 2 parallel to the second sleeve, a worm being provided on one end of the screw rod 2 corresponding to the outer ring, a worm gear being meshed with a worm gear on the side of the worm gear, and the worm gear being fixedly connected to the screw rod 1 through the screw rod;

[0019] The three screw rods 2 are rotated synchronously to drive the second sleeve to move linearly along the axial direction of the mounting ring toward one side of the Pitot tube. At the same time, the engagement of the worm and the worm wheel drives the screw rod 1 passing through the end face of the worm wheel to rotate, so that the outer ring adapted on the screw rod 1 and the first sleeve installed on the outer ring move along the radial direction of the mounting ring toward one side of the thermal sensor under the guidance of the corresponding guide rod and are outwrapped on the outside of the thermal sensor.

[0020] Furthermore, a sprocket is provided on one end of each of the screw rods 2 away from the worm, and a transmission chain is engaged on the outside of the three sprockets. A fixing plate is provided on the outside of the transmission chain, and the fixing plate is used for the installation of each of the screw rods 2. One of the screw rods 2 is provided with a motor fixed on the outer end of the fixing plate.

[0021] Furthermore, a first outer gear ring is coaxially arranged on the outer side of the first inner gear ring arranged on each of the first sleeves, and a second inner gear ring is rotatably arranged on the mounting ring and meshed with each of the first outer gear rings.

[0022] Furthermore, a central shaft is passed through the end surface of the bladed rotor, a second gear is sleeved on the central shaft, a second outer gear ring is coaxially provided on the outer side of the second inner gear ring, and the second outer gear ring is meshed with the second gear;

[0023] The second gear is rotated to drive the two bladed rotors of the synchronous gear drive to rotate through the central shaft, and the second inner gear ring is driven to rotate through the engagement of the second gear and the second outer gear ring, so that the first inner gear ring set on each first sleeve rotates under the meshing transmission of the second inner gear ring and the first outer gear ring.

[0024] The monitoring method of the inlet air volume adopts a multimodal data fusion algorithm based on the combination of Venturi reference value and sensor array correction in the straight pipe section of the coal mill.

[0025] Compared with the prior art, the present invention has the following beneficial effects: the present invention provides a cleaning component, which can automatically and regularly clean the monitoring sensor in a rotating manner, thereby reducing the possibility of coal ash dust covering the coal mill inlet, and at the same time, collect the removed coal ash dust in a concentrated manner, thereby realizing online cleaning and collection, without the need for long-term shutdown, and improving maintenance efficiency; the present invention also provides a monitoring component and a Venturi tube structure, and adopts a multimodal data fusion algorithm based on the combination of Venturi reference value and sensor array correction, which can partially replace the straight pipe section of the coal mill with a Venturi tube structure, thereby making up for the shortcomings of the straight pipe section and avoiding measurement fluctuations exceeding the measurement range, and arranging multiple measuring points on the cross section of the straight pipe section to cover the center and edge areas, thereby solving the problem of single-point measurement being interfered by airflow turbulence and dust, and reducing data errors. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] The accompanying drawings, which constitute part of this application, are intended to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are intended to explain the present invention and do not constitute an undue limitation of the present invention. In the accompanying drawings:

[0027] Figure 1 A three-dimensional structural diagram of an embodiment of the present invention from one perspective;

[0028] Figure 2 A three-dimensional structural diagram showing a combination of a monitoring component and a dust cleaning component according to an embodiment of the present invention;

[0029] Figure 3 A three-dimensional structural diagram of a monitoring assembly according to an embodiment of the present invention from one perspective;

[0030] Figure 4 A planar structural diagram of a monitoring assembly according to an embodiment of the present invention from one perspective;

[0031] Figure 5 A three-dimensional structural diagram of a dust cleaning assembly according to an embodiment of the present invention from one perspective;

[0032] Figure 6 for Figure 5 A in the middle is an enlarged structural diagram;

[0033] Figure 7 A three-dimensional structural diagram of a dust cleaning assembly according to an embodiment of the present invention from another perspective;

[0034] Figure 8 for Figure 7 The enlarged structural diagram at B in the middle;

[0035] Figure 9 for Figure 7 The enlarged structural diagram at C in the middle;

[0036] Figure 10This is a schematic diagram of the transmission connection structure of the internal power structure of the ash collection unit according to one embodiment of the present invention;

[0037] Figure 11 FIG1 is a schematic planar structural diagram of a cross section of a Venturi tube structure according to an embodiment of the present invention.

[0038] In the figure: 100, monitoring assembly; 101, support ring; 102, Y-shaped bracket; 103, thermal sensor; 104, Pitot tube; 200, Venturi tube structure; 201, inlet section; 202, contraction section; 203, throat; 204, expansion section; 205, pressure tapping hole; 300, dust cleaning assembly; 301, mounting ring; 302, first sleeve; 303, second sleeve; 1, dust cleaning unit; 11, cleaning brush; 12, first inner gear ring; 13, first gear; 14, first outer gear ring; 2, Ash collection unit; 21. Shell; 22. Blade-shaped rotor; 23. Conduit; 231. Extension tube; 24. Movable ring 1; 25. Hose; 26. Negative pressure interface; 27. Movable ring 2; 28. Drain pipe; 3. Transmission mechanism; 31. Screw 1; 32. Guide rod; 33. Outer ring; 34. Internally threaded side plate; 35. Screw 2; 351. Worm; 36. Worm gear; 37. Sprocket; 38. Drive chain; 39. Fixed plate; 391. Motor; 4. Second inner gear ring; 5. Second gear; 6. Second outer gear ring. DETAILED DESCRIPTION

[0039] The technical solutions in the embodiments of the present invention will be described clearly and completely below. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. In the absence of conflict, the embodiments in this application and the features in the embodiments can be combined with each other. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0040] like Figure 1-11 As shown, the inlet air volume monitoring device of the present invention is applied to a coal mill and includes a monitoring assembly 100 for monitoring the inlet air volume of the coal mill. The monitoring assembly 100 includes a support ring 101 correspondingly arranged on the straight pipe section of the coal mill and a Y-shaped bracket 102 coaxially arranged within the support ring 101. The center and any one arm of the Y-shaped bracket 102 are respectively provided with openings, and the openings are respectively provided with a thermal sensor 103 and a pitot tube 104;

[0041] The venturi tube structure 200 is extended and detachably mounted on the straight pipe section of the coal mill, and is used to convert the wind speed into a pressure difference signal according to the principles of fluid mechanics, and then calculate the air volume through a calibration formula;

[0042] The cleaning assembly 300 includes mounting rings 301 spaced apart in the straight pipe section of the coal mill, a first sleeve 302 arranged in a circular array on the mounting ring 301 and moving radially along the mounting ring 301, and a second sleeve 303 centrally arranged on the mounting ring 301. A cleaning unit 1 for performing rotational cleaning on the thermal sensor 103 and the Pitot tube 104 distributed at corresponding positions is provided in each of the first sleeves 302 and the second sleeve 303. An ash collecting unit 2 for synchronously collecting the removed coal ash dust during the rotational cleaning process is provided on the end of each of the first sleeves 302 away from the support ring 101.

[0043] In a specific implementation, a monitoring assembly 100 with a flange that can be quickly and detachably installed is used at the inlet of the straight pipe section of the coal mill, and a Venturi tube structure 200 is extended from the straight pipe section of the coal mill so that the monitoring assembly 100 is placed in the middle position. The monitoring assembly 100 includes a support ring 101 with a flange installed on the straight pipe section, a Y-shaped bracket 102 that is rotatably installed through a groove in its inner wall, and a thermal sensor 103 and a Pitot tube 104 installed in the support arm and the center turning through opening of the Y-shaped bracket 102. This can effectively ensure the accuracy of monitoring by measuring the position of the measuring point when the cross-section of the straight pipe section changes.

[0044] The mounting ring 301 that is also installed and extended into the straight pipe section, the first sleeve 302 that moves radially on the mounting ring 301, and the second sleeve 303 installed in the center of the mounting ring 301 can be outsourced to the corresponding thermal sensor 103 and the Pitot tube 104 in turn. During the cleaning process, the cleaning unit 1 can be used to rotationally clean the coal ash dust attached to the outside of the thermal sensor 103 and the Pitot tube 104, while the ash collecting unit 2 can be used to collect the coal ash dust in a concentrated manner, thereby realizing online cleaning and collection without the need for long-term shutdown, improving maintenance efficiency, and ensuring monitoring accuracy.

[0045] It should be noted that, in the cross section of the straight pipe section, a total of four measuring points are arranged at the center and edge according to the structural form of the Y-shaped bracket 102 to cover the center and edge areas. Since the center of the Y-shaped bracket 102 is in the high-speed area of the inlet air volume, and the Pitot tube 104 is resistant to erosion, and the edge of the Y-shaped bracket 102 is in the low-speed area of the inlet air volume, the thermal sensor 103 has high sensitivity.

[0046] In one embodiment, the venturi tube structure 200 includes an inlet section 201, a contraction section 202, a throat section 203, and an expansion section 204, which are sequentially arranged along the airflow direction. A surface of the throat section 203 is provided with a plurality of adjacent pressure holes 205 distributed along the circumferential direction and along the airflow direction.

[0047] The pressure-taking hole 205 is used to equalize the pressure inside the venturi tube structure 200. This design utilizes an integrated molding process at the inlet of the straight tube section along the airflow direction to combine the inlet section 201, the contraction section 202, the throat 203, and the expansion section 204. The key parameters of the venturi tube structure 200 are defined as follows:

[0048] The inlet section 201 (D1) has the same diameter as the straight pipe section of the coal mill and a length ≥ 1.5D1 to ensure stable airflow;

[0049] The contraction section 202 has a cone angle of 15° to 20°, which allows for smooth acceleration of the airflow;

[0050] At the throat 203 (D2), the smallest cross-section, the diameter ratio β = D2 / D1 = 0.5 to 0.7 (usually 0.6);

[0051] The expansion section 204 has a cone angle of 5° to 7°, which gradually restores the pressure and reduces energy loss.

[0052] Differential pressure-air volume conversion formula

[0053] The air volume Q is derived from the Bernoulli equation:

[0054]

[0055] C: Flow coefficient (needs to be calibrated, usually 0.95 to 0.99);

[0056] ΔP: pressure difference between inlet and throat (Pa);

[0057] ρ: gas density (kg / m 3 );

[0058] β: throat diameter ratio, 0.6, when β is less than 0.5, the pressure loss increases dramatically.

[0059] It should be noted that the four pressure holes 205 circumferentially turned on the throat 203 are inclined at 45° along the airflow direction to reduce the deposition of fly ash and dust.

[0060] In one embodiment, the dust cleaning unit 1 includes a cleaning brush 11 eccentrically disposed on one side of each of the first sleeve 302 and the second sleeve 303, and a first inner gear ring 12 correspondingly disposed at the end of each of the first sleeve 302 and the second sleeve 303. The cleaning brush 11 is provided with a first gear 13 meshing with the first inner gear ring 12.

[0061] The transmission force drives the synchronous rotation of each of the first sleeves 302 and the second sleeves 303, so that the cleaning brush 11 follows the first sleeves 302 and the second sleeves 303 in orbital cleaning. At the same time, the meshing of the first inner ring gear 12 and the first gear 13 drives the cleaning brush 11 to rotate and clean the dust. In this design, due to the cleaning brush 11 installed eccentrically in the first sleeve 302 and the second sleeve 303, the first gear 13 welded to the end of the cleaning brush 11, and the first inner ring gear 12 welded to the end of the first sleeve 302 and the second sleeve 303, once the first sleeve 302 and the second sleeve 303 are rotated by an external force, they will drive the corresponding first sleeve 302 and the second sleeve 303 to rotate, causing the cleaning brush 11 to orbit. At the same time, the meshing of the first inner ring gear 12 and the first gear 13 drives the cleaning brush 11 to rotate. These two rotation modes ensure that the soot dust attached to the corresponding sensor surface is removed by the cleaning brush 11, ensuring comprehensive removal.

[0062] In one embodiment, the ash collecting unit 2 includes a shell 21 correspondingly arranged on one side of the mounting ring 301 and two vane rotors 22 arranged in the shell 21 and moving relative to each other through synchronous gear transmission. The outside of the shell 21 is connected to a conduit 23 with a rotation direction opposite to that of the two vane rotors 22. An extension pipe 231 is provided on the end of the conduit 23 away from the shell 21. The outer end of the extension pipe 231 is arranged toward the pressure taking hole 205. A movable ring 1 24 is rotatably provided on a section of the extension pipe 231. The circumference of the movable ring 1 24 is provided with a number of hoses 25 equal to the first sleeve 302. A negative pressure interface 26 is provided on the end of the hose 25 away from the movable ring 1 24. A movable ring 2 27 rotatably connected to the end of the first sleeve 302 is provided on the negative pressure interface 26. A discharge pipe 28 is provided on the other end of the shell 21 opposite to the conduit 23. The outer end of the discharge pipe 28 is connected to the closed dust collecting chamber.

[0063] During the rotation of the two relatively moving blade rotors 22 distributed inside the shell 21, the gas at the outer end of the extension pipe 231 and the corresponding pipe opening of the hose 25 installed on the extension pipe 231 is sucked in through the conduit 23 until the cleared coal ash dust is sucked into the dust collecting chamber through the exhaust pipe 28. With this design, the shell 21 installed on one side of the mounting ring 301 and the two relatively distributed blade rotors 22 installed inside the shell 21 drive the two relatively distributed blade rotors 22 to rotate under the synchronous gear transmission, so that the conduit 23 on the shell 21, which is opposite to the rotation and fixed by welding, and the extension tube 231 welded to the outer end of the conduit 23, can negatively suck the coal ash dust blocked at the pressure taking hole 205, and the movable ring 1 24 rotatably installed on a slotted section of the extension tube 231 and the hoses 25 distributed on the movable ring 1 24 and connected to the first sleeve 302, can suck the removed coal ash dust through the hoses 25 during the rotation of the two blade rotors 22, until it enters the dust collecting chamber through the discharge pipe 28 welded to the other end of the shell 21 opposite to the conduit 23 for collective collection.

[0064] It should be noted that the negative pressure interface 26 installed on the hose 25 near the port of the first sleeve 302 and the movable ring 27 welded on the negative pressure interface 26, wherein the movable ring 27 is rotatably installed at the corresponding end of the first sleeve 302, that is, when the first sleeve 302 rotates, since the hose 25 is movably installed on the first sleeve 302 through the negative pressure interface 26, the hose 25 will not be entangled, thereby ensuring the practicality of inhaling coal ash dust.

[0065] It should be noted that a one-way valve is installed on the extension tube 231 to guide gas in one direction.

[0066] In one embodiment, the movable ring 1 24 is further provided with a hose 25 communicating with the second sleeve 303;

[0067] The hose 25 is used to negatively pressure transport the coal ash dust within the second sleeve 303. This design allows the hose 25, installed on the second sleeve 303 and connected to the movable ring 1 24, to establish a transport channel through the hose 25 and the extension tube 231 during the rotation of the two oppositely mounted vane rotors 22, thereby sucking in the coal ash dust.

[0068] In one embodiment, a transmission mechanism 3 is provided on the circumference of the second sleeve 303 for synchronously driving each of the first sleeves 302 to move radially along the mounting ring 301;

[0069] The transmission mechanism 3 includes a screw rod 31 and a guide rod 32 respectively arranged between the mounting ring 301 and the first sleeve 302. The screw rod 31 and the guide rod 32 are adapted to be provided with an outer ring 33 rotatably connected to the outer end of the movable ring 27. The second sleeve 303 is provided with an internally threaded side plate 34 at the position corresponding to the screw rod 31 and the guide rod 32. The end surface thread of the internally threaded side plate 34 is adapted to be provided with a screw rod 2 35 parallel to the second sleeve 303. The screw rod 2 35 is provided with a worm 351 at one end corresponding to the outer ring 33. The side of the worm 351 is meshed with a worm wheel 36. The worm wheel 36 is fixedly connected to the screw rod 1 31 through the screw rod 1.

[0070] The three screw rods 2 35 are rotated synchronously to drive the second sleeve 303 to move linearly along the axial direction of the mounting ring 301 toward the side of the Pitot tube 104. At the same time, the engagement of the worm 351 and the worm wheel 36 drives the screw rod 1 31 passing through the end face of the worm wheel 36 to rotate, so that the outer ring 33 adapted on the screw rod 1 31 and the first sleeve 302 installed on the outer ring 33 move along the radial direction of the mounting ring 301 toward the side of the thermal sensor 103 under the guidance of the corresponding guide rod 32 and are outwardly wrapped around the outside of the thermal sensor 103. In this design, through the three internal threaded side plates 34 welded in a circular array on the circumference of the second sleeve 303 and the screw rod 2 35 with a slotted thread on the end face of the internal threaded side plate 34, when the three screw rods 2 35 rotate synchronously, the internal threaded side plates 34 installed on the outside of the corresponding screw rods 2 35 will drive the second sleeve 303 to move linearly along its axial direction toward one side of the pitot tube 104, so that the second sleeve 303 is outwardly wrapped around the outside of the pitot tube 104. At the same time, the worm 351 welded at the end of the screw rod 2 35 and the worm wheel 36 meshing with its side, when the worm 351 rotates along with the screw rod 2 35 When it moves, it will engage and drive the screw rod 31 fixed on the end face of the worm wheel 36 to rotate, so that the outer ring 33, which is threadedly adapted on the screw rod 31 and rotatably connected to the outside of the movable ring 27, moves linearly along the radial direction of the installed ring 301 toward the thermal sensor 103 under the guidance of the guide rod 32 with a slotted sliding connection on the other side, thereby making the movable ring 2 27 and the first sleeve 302 rotating in sequence on the outer ring 33 and outwardly wrapped around the outside of the thermal sensor 103, and synchronously forming a closed area for cleaning outside each thermal sensor 103 and the Pitot tube 104.

[0071] It should be noted that the through-holes opened in the axial direction on the circumferential surface of each first sleeve 302 by turning are capable of switching the thermal sensor 103 between a sealed state and an unsealed state.

[0072] In one embodiment, a sprocket 37 is sleeved on one end of each screw rod 35 away from the worm 351. A transmission chain 38 is meshed with the outside of the three sprockets 37. A fixed plate 39 is provided on the outside of the transmission chain 38 for each screw rod 35 to be passed through and installed. One of the screw rods 35 is provided with a motor 391 fixed to the outer end of the fixed plate 39. In this design, by having the sprockets 37 fixed on the ends of the three screw rods 35 and the transmission chain 38 meshed with the outside of the sprockets 37, once the motor 391 connected to the end of one of the screw rods 35 via a coupling is started, it will drive the corresponding screw rod 35 to rotate. At the same time, through the meshing of the teeth of the sprocket 37 and the rollers of the transmission chain 38, the transmission chain 38 serves as the transmission medium, thereby achieving synchronous rotation of the three screw rods 35 distributed in a circular array, providing an external force for the movement of the second sleeve 303.

[0073] It should be noted that the fixing plate 39 installed on the outside of the transmission chain 38 provides a working surface for the installation of the motor 391.

[0074] In one embodiment, a first outer gear ring 14 is coaxially mounted on the outside of the first inner gear ring 12 mounted on each first sleeve 302, and a second inner gear ring 4 is rotatably mounted on the mounting ring 301 and meshes with each first outer gear ring 14. With this design, by virtue of the first outer gear ring 14 coaxially welded to the outside of the first inner gear ring 12 and the second inner gear ring 4 being slotted and rotatably mounted on the mounting ring 301, when the second inner gear ring 4 receives an external force, the meshing of the second inner gear ring 4 and the first outer gear ring 14 drives the first sleeve 302 to rotate, while the meshing of the first inner gear ring 12 and the first gear 13 drives the cleaning brush 11 to rotate.

[0075] It should be noted that the first inner gear ring 12 is welded to the end of the first sleeve 302 .

[0076] In one embodiment, a central shaft is provided through the end surface of the vane-shaped rotor 22, and a second gear 5 is sleeved on the central shaft. A second outer gear ring 6 is coaxially provided on the outer side of the second inner gear ring 4, and the second outer gear ring 6 is meshed with the second gear 5.

[0077] Rotating the second gear 5 drives the two synchronously geared vane rotors 22 to rotate via the central shaft. Simultaneously, the meshing of the second gear 5 and the second outer gear ring 6 drives the second inner gear ring 4 to rotate, causing the first inner gear ring 12 provided on each first sleeve 302 to rotate under the meshing drive of the second inner gear ring 4 and the first outer gear ring 14. This design utilizes the second gear 5, which is sleeved on the central shaft portion extending through the end face of a vane rotor 22 and extending outside the housing 21, and the meshing of the second gear 5 with the second outer gear ring 6. As the two vane rotors 22 rotate, negative pressure suction is generated, while simultaneously transmitting force to drive the second inner gear ring 4 coaxially welded to and positioned inside the second outer gear ring 6. This force is then transmitted through the meshing of the second inner gear ring 4 and the first outer gear ring 14 to drive the first inner gear ring 12 and the first gear 13 meshed inside the first inner gear ring 12. This achieves force transmission in this embodiment, ensuring effective implementation.

[0078] It should be noted that the end of the central shaft passing through the end surface of the single-blade rotor 22 will be equipped with a matching motor structure through a coupling for electric drive.

[0079] The monitoring method of the inlet air volume adopts a multimodal data fusion algorithm based on the combination of Venturi reference value and sensor array correction in the straight pipe section of the coal mill.

[0080] Specific methods:

[0081] Venturi reference value: Calculate the initial air volume Q through ΔP Venturi ;

[0082] Sensor array calibration: Take the weighted average Q of the air volume at the four points of the Y-shaped bracket 102 Array (edge weight 0.2, center 0.6);

[0083] Dynamic compensation output: Q final =0.7Q Venturi +0.3Q Array +ΔQ density ;

[0084] ΔQ density :Real-time compensation of temperature, pressure and humidity. An integrated temperature, pressure and humidity sensor (such as Bosch BME680) can be installed to synchronously collect gas density parameters.

[0085] If the deviation between the Venturi reference value and the sensor array calibration data continues to be greater than 5%, the sensor is judged to be faulty, the mode is switched to pure Venturi mode, and an alarm is issued.

[0086] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

[0087] It should be noted that if the embodiments of the present invention involve directional indications (such as up, down, left, right, front, back, etc.), the directional indications are only used to explain the relative position relationship, movement status, etc. between the components under a certain specific posture. If the specific posture changes, the directional indications will also change accordingly.

[0088] In addition, if there are descriptions involving "first", "second", etc. in the embodiments of the present invention, the descriptions of "first", "second", etc. are only for descriptive purposes and cannot be understood as indicating or suggesting their relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of such features. In addition, the meaning of "and / or" appearing throughout the text includes three parallel schemes. Taking "A and / or B" as an example, it includes scheme A, or scheme B, or schemes in which A and B are satisfied at the same time. In addition, "several" refers to more than two. In addition, the technical solutions between the various embodiments can be combined with each other, but it must be based on the ability of ordinary technicians in this field to implement. When the combination of technical solutions is mutually contradictory or cannot be implemented, it should be deemed that such a combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

Claims

1. A device for monitoring inlet air volume, comprising a monitoring component (100) for monitoring the inlet air volume of a coal mill, characterized in that: The monitoring assembly (100) comprises a support ring (101) correspondingly arranged on the straight pipe section of the coal mill and a Y-shaped bracket (102) coaxially arranged in the support ring (101); a through opening is correspondingly arranged on the center and any one arm of the Y-shaped bracket (102); a thermal sensor (103) and a pitot tube (104) are correspondingly arranged in the through opening; The venturi tube structure (200) is extended and detachably arranged on the straight pipe section of the coal mill, and is used to convert the wind speed into a pressure difference signal according to the principle of fluid mechanics, and then calculate the air volume through a calibration formula; A ash cleaning assembly (300) comprises mounting rings (301) arranged at intervals in a straight pipe section of a coal mill, first sleeves (302) arranged in a circular array on the mounting rings (301) and radially moving along the mounting rings (301), and a second sleeve (303) arranged centrally on the mounting rings (301), wherein each of the first sleeves (302) and the second sleeves (303) is provided with an ash cleaning unit (1) for performing rotary ash cleaning on the thermal sensors (103) and the pitot tubes (104) distributed at corresponding positions, and an ash collecting unit (2) for synchronously collecting the removed coal ash dust during the rotary ash cleaning process is provided on one end of each of the first sleeves (302) away from the support ring (101).

2. The inlet air volume monitoring device according to claim 1, characterized in that: The venturi tube structure (200) comprises an inlet section (201), a contraction section (202), a throat section (203) and an expansion section (204) arranged in sequence along the direction of the airflow; a surface of the throat section (203) is provided with a plurality of adjacent pressure-taking holes (205) distributed along the circumferential direction and along the direction of the airflow; The pressure-taking hole (205) is used to equalize the pressure inside the Venturi tube structure (200).

3. The inlet air volume monitoring device according to claim 2, characterized in that: The dust cleaning unit (1) comprises a cleaning brush (11) eccentrically arranged on one side of each of the first sleeve (302) and the second sleeve (303), and a first inner gear ring (12) correspondingly arranged at the end of each of the first sleeve (302) and the second sleeve (303), wherein the cleaning brush (11) is provided with a first gear (13) meshing with the first inner gear ring (12); The transmitting force drives the first sleeve (302) and the second sleeve (303) to rotate synchronously, so that the cleaning brush (11) follows the first sleeve (302) and the second sleeve (303) to perform orbital cleaning and the meshing of the first inner gear ring (12) and the first gear (13) drives the cleaning brush (11) to rotate and clean.

4. The inlet air volume monitoring device according to claim 3, characterized in that: The ash collecting unit (2) comprises a shell (21) correspondingly arranged on one side of the mounting ring (301) and two bladed rotors (22) arranged in the shell (21) and moving relative to each other through synchronous gear transmission, a conduit (23) in a rotation direction opposite to that of the two bladed rotors (22) is provided on the outside of the shell (21), an extension tube (231) is provided on the end of the conduit (23) away from the shell (21), the outer end of the extension tube (231) is arranged toward the pressure taking hole (205), and the extension tube (231) is provided to the pressure taking hole (205). 1) The upper section is provided with a rotatable movable ring (24), the circumference of the movable ring (24) is provided with a number of hoses (25) equal to the number of the first sleeve (302), the end of the hose (25) away from the movable ring (24) is provided with a negative pressure interface (26), the negative pressure interface (26) is provided with a movable ring (27) rotatably connected to the end of the first sleeve (302), the other end of the housing (21) opposite to the guide tube (23) is provided with a drain pipe (28), the outer end of the drain pipe (28) is connected to the closed dust collecting chamber; During the rotation of the two relatively moving vane-shaped rotors (22) distributed inside the housing (21), the gas at the outer end of the extension pipe (231) and the corresponding pipe opening of the hose (25) installed on the extension pipe (231) is sucked in through the conduit (23) until the cleaned coal ash dust is sucked into the dust collecting chamber through the discharge pipe (28).

5. The inlet air volume monitoring device according to claim 4, characterized in that: The movable ring (24) is further provided with a hose (25) communicating with the second sleeve (303); The hose (25) is used to transport the coal ash dust inside the second sleeve (303) under negative pressure.

6. The inlet air volume monitoring device according to claim 4, characterized in that: The circumferential surface of the second sleeve (303) is provided with a transmission mechanism (3) for synchronously driving each of the first sleeves (302) to move radially along the mounting ring (301); The transmission mechanism (3) includes a screw rod (31) and a guide rod (32) respectively arranged between the mounting ring (301) and the first sleeve (302); the screw rod (31) and the guide rod (32) are adapted to be provided with an outer ring (33) rotatably connected to the outer end of the movable ring (27); an internal threaded side plate (34) is provided on the second sleeve (303) at positions corresponding to the screw rod (31) and the guide rod (32); the end surface thread of the internal threaded side plate (34) is adapted to be provided with a screw rod (35) parallel to the second sleeve (303); a worm (351) is provided on one end of the screw rod (35) corresponding to the outer ring (33); a worm wheel (36) is meshed with the side of the worm wheel (351); the worm wheel (36) is fixedly connected to the screw rod (31) through the screw rod; The three screw rods 2 (35) are rotated synchronously to drive the second sleeve (303) to move linearly along the axial direction of the mounting ring (301) toward the side of the Pitot tube (104), and at the same time, the screw rod 1 (31) passed through the end face of the worm wheel (36) is driven to rotate through the engagement of the worm (351) and the worm wheel (36), so that the outer ring (33) adapted on the screw rod 1 (31) and the first sleeve (302) installed on the outer ring (33) move along the radial direction of the mounting ring (301) toward the side of the thermal sensor (103) under the guidance of the corresponding guide rod (32) and are outwardly wrapped around the outside of the thermal sensor (103).

7. The inlet air volume monitoring device according to claim 6, characterized in that: A sprocket (37) is sleeved on one end of each of the second screw rods (35) away from the worm (351), and a transmission chain (38) is meshed with the outside of the three sprockets (37). A fixing plate (39) is provided on the outside of the transmission chain (38). The fixing plate (39) is used for the installation of each of the second screw rods (35), and one of the second screw rods (35) is provided with a motor (391) fixed to the outer end of the fixing plate (39).

8. The inlet air volume monitoring device according to claim 3, characterized in that: A first outer gear ring (14) is coaxially arranged on the outer side of the first inner gear ring (12) arranged on each first sleeve (302), and a second inner gear ring (4) is rotatably arranged on the mounting ring (301) and is meshed with each first outer gear ring (14).

9. The inlet air volume monitoring device according to claim 8, characterized in that: A central shaft is provided through the end surface of the bladed rotor (22), a second gear (5) is sleeved on the central shaft, a second outer gear ring (6) is coaxially provided on the outer side of the second inner gear ring (4), and the second outer gear ring (6) is meshedly connected with the second gear (5); The second gear (5) is rotated to drive the two bladed rotors (22) of the synchronous gear transmission to rotate through the central shaft, and the second inner gear ring (4) is driven to rotate through the meshing of the second gear (5) and the second outer gear ring (6), so that the first inner gear ring (12) provided on each first sleeve (302) rotates under the meshing transmission of the second inner gear ring (4) and the first outer gear ring (14).

10. A method for monitoring inlet air volume, used in the inlet air volume monitoring device according to any one of claims 1 to 9, characterized in that: A multimodal data fusion algorithm based on Venturi reference value and sensor array correction is used in the straight pipe section of the coal mill.

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