Thermal power online unit capacity prediction method based on deep neural network

Abstract

The invention discloses a thermal power online unit capacity prediction method based on a deep neural network, and relates to the technical field of auxiliary equipment for thermal power units. According to the thermal power on-line unit capacity prediction method based on the deep neural network, the thermal power on-line unit capacity prediction method based on the deep neural network is fixed in a combustion cavity through a limiting mechanism; the limiting mechanism can drive a second multi-stage electric telescopic rod provided with high-temperature-resistant temperature probes to move in the position fixing process, so that the high-temperature-resistant temperature probes are evenly distributed in the combustion cavity, and the high-temperature-resistant temperature probes are inserted into a coal pile through the second multi-stage electric telescopic rod. The coal bulking mechanism is arranged on the belt conveyor, combustion states of coal at different depths are detected, the coal falling from the belt conveyor is guided through the guide plate, the coal on the guide plate is stirred through the coal anti-blocking mechanism, the coal is prevented from blocking the guide plate, and the coal anti-blocking mechanism can drive the coal bulking mechanism to work while working.

Description

Technical Field

[0001] The present invention relates to the technical field of auxiliary equipment for thermal power units, and in particular to a method for predicting the capacity of thermal power online units based on a deep neural network. Background Art

[0002] When thermal power generating units are working, they generate steam by burning coal, and the generated steam drives the turbine to rotate, thereby generating electricity. However, since thermal power generating units require a large amount of coal, the coal is transported from all over the country. During the transportation process, the coal will be affected by the outside world and have different humidity conditions. Due to the different humidity of the coal, the combustion degree of the coal will also change. During the combustion process, only the combustion temperature in the combustion chamber can be detected, and the combustion degree of the coal at different depths in the combustion chamber cannot be accurately grasped, which will lead to waste of coal resources and incomplete combustion of the coal and failure to generate a large amount of steam. At the same time, the coal in the combustion chamber is loaded by belt conveyors, but the coal will accumulate at the falling position during the loading process and cannot be evenly distributed in the combustion chamber, which can easily cause the coal to be discharged from the combustion chamber due to incomplete combustion. Summary of the invention

[0003] In order to overcome the shortcomings in the background technology, the present invention discloses a method for predicting the capacity of an online thermal power unit based on a deep neural network. The present invention fixes the method for predicting the capacity of an online thermal power unit based on a deep neural network in a combustion chamber through a limiting mechanism. The limiting mechanism drives a second multi-stage electric telescopic rod equipped with a high-temperature resistant temperature detection needle to move during the fixing process, so that the high-temperature resistant temperature detection needle is evenly distributed in the combustion chamber, and the high-temperature resistant temperature detection needle is inserted into the coal pile through the second multi-stage electric telescopic rod to detect the combustion state of coal at different depths, and the coal dropped from the belt conveyor is guided by a guide plate, and the coal on the guide plate is moved by a coal anti-blocking mechanism to prevent the guide plate from being blocked by coal. The coal anti-blocking mechanism drives the coal scattering mechanism to work while working, and the coal dropped from the guide plate is evenly scattered in the combustion chamber through the coal scattering mechanism to ensure that the coal can be fully burned.

[0004] In order to achieve the above-mentioned object of the invention, the present invention adopts the following technical scheme: A method for predicting the capacity of an online thermal power unit based on a deep neural network includes a limiting mechanism, which is characterized in that: a second multi-stage electric telescopic rod arranged equidistantly is fixedly connected to the regulating end of the limiting mechanism, and the telescopic end of the second multi-stage electric telescopic rod is connected to a high-temperature resistant temperature detection needle through a high-temperature resistant connecting rod, the insertion depth of each high-temperature resistant temperature detection needle is controlled by the equidistantly arranged second multi-stage electric telescopic rod, and the coal combustion state at different depths is detected by each high-temperature resistant temperature detection, a guide plate is fixedly connected to the feeding end of the limiting mechanism, and a coal anti-blocking mechanism and a coal bulking mechanism are installed in the limiting mechanism, the toggle end of the coal anti-blocking mechanism is in contact with the inner wall of the guide plate, and the rotating end of the coal anti-blocking mechanism is in contact with the driving end of the coal bulking mechanism.

[0005] The limiting mechanism includes a positioning frame, a first multi-stage electric telescopic rod and a contact plate. The outer wall of the positioning frame is fixedly connected to the first multi-stage electric telescopic rods arranged equidistantly, and the telescopic ends of the first multi-stage electric telescopic rods are fixedly connected to the contact plate. The positioning frame is installed with a coal anti-blocking mechanism and a coal bulking mechanism.

[0006] A second multi-stage electric telescopic rod is fixedly connected to each telescopic rod of the first multi-stage electric telescopic rod. When the first multi-stage electric telescopic rod is extended, it drives each second multi-stage electric telescopic rod to move, so that the second multi-stage electric telescopic rods are evenly distributed in the combustion chamber.

[0007] The coal anti-blocking mechanism includes a fixed block, a transmission plate, a toggle plate, a servo motor, a bearing, a gear ring, a motor gear and a transmission rod. The fixed blocks are equidistantly arranged and fixedly connected to the inner wall of the positioning frame, and the bearings are fixedly connected between the fixed blocks. The rotating end of the bearing is fixedly connected to a transmission plate, and the transmission plate is fixedly connected to transmission rods arranged equidistantly. The transmission rod is fixedly connected to a toggle plate, and one side of the toggle plate is in contact with the inner wall of the guide plate. A servo motor is fixedly connected to one of the fixed blocks, and the servo motor is connected to the motor gear through a motor shaft. The gear ring is located on the outer wall of the transmission plate and is fixedly connected, and the position of the gear ring corresponds to that of the motor gear and they are meshed.

[0008] The coal bulk material mechanism includes a pushing rod, a fixed rod, a first rotating joint, and a limit block. The fixed rod is equidistantly arranged and fixedly connected to the bottom end of the positioning frame, and the bottom end of the fixed rod is connected to the flip plate through the first rotating joint. The limit blocks are equidistantly arranged and fixedly connected to the inner wall of the positioning frame, and the pushing rod is slidably connected to the limit block, and the upper and lower ends of the pushing rod are respectively connected to the flip plate through a transmission assembly.

[0009] The transmission assembly includes a first annular transmission plate, a second annular transmission plate, a first semicircular protrusion and a second semicircular protrusion, the second annular transmission plate is located on the outer wall of the transmission plate and is fixedly connected, and the lower surface of the second annular transmission plate is fixedly connected with the second semicircular protrusions arranged equidistantly, the first annular transmission plate is located at the top end of the push rod and is fixedly connected, and the upper surface of the first annular transmission plate is fixedly connected with the first semicircular protrusions arranged equidistantly, and the position of the first semicircular protrusion corresponds to the position of the second semicircular protrusion and is contacted and connected.

[0010] The bottom end of the push rod is connected to the flip plate through a second rotating joint.

[0011] The flap plate includes a connecting plate and a high temperature resistant fabric. The connecting plates are respectively located on the rotating ends of the first rotating joints arranged equidistantly and are fixedly connected, and the high temperature resistant fabric is fixedly connected between the connecting plates. A sliding groove is provided on the connecting plate, and the rotating end of the second rotating joint is slidably connected in the sliding groove.

[0012] A spring is fixedly connected to the limit block, and one end of the spring is fixedly connected to the lower surface of the first annular transmission plate. The position of the spring corresponds to and is sleeved with the position of the push rod.

[0013] When in use, the staff puts the positioning frame into the combustion chamber through the coal inlet of the combustion chamber, and starts the first multi-stage electric telescopic rod on the positioning frame through the external control device, so that the first multi-stage electric telescopic rod is extended, and the contact plate on the first multi-stage electric telescopic rod is in contact with the inner wall of the combustion chamber, and the position of the positioning frame is fixed. Each section of the first multi-stage electric telescopic rod will drive each second multi-stage electric telescopic rod to move during the extension process. Since the length of each section of the first multi-stage electric telescopic rod is equal, the second multi-stage electric telescopic rods will be evenly distributed in the combustion chamber. The high-temperature resistant temperature detection needle is inserted into different depths of the coal pile through each second multi-stage electric telescopic rod. The combustion state of coal at different depths is detected through the high-temperature resistant temperature detection, and the detection data is transmitted to the external control device for the staff to analyze and predict. The servo motor is started through the external control device, and the servo motor drives the transmission plate fixed with the gear ring to rotate through the motor gear. The transmission plate drives the toggle plate to move through the transmission rod during the rotation process, and the coal on the guide plate is toggled through the toggle plate to prevent the coal from blocking the discharge port of the guide plate.

[0014] Due to the adoption of the above technical solution, the present invention has the following beneficial effects: The method for predicting the capacity of an online thermal power unit based on a deep neural network described in the present invention fixes the method for predicting the capacity of an online thermal power unit based on a deep neural network in a combustion chamber through a limiting mechanism. The limiting mechanism drives a second multi-stage electric telescopic rod equipped with a high-temperature resistant temperature detection needle to move during the fixing process, so that the high-temperature resistant temperature detection needle is evenly distributed in the combustion chamber, and the high-temperature resistant temperature detection needle is inserted into the coal pile through the second multi-stage electric telescopic rod to detect the combustion state of coal at different depths, and the coal dropped from the belt conveyor is guided by the guide plate, and the coal on the guide plate is moved by the coal anti-blocking mechanism to prevent the guide plate from being blocked by the coal. The coal anti-blocking mechanism drives the coal scattering mechanism to work while working, and the coal dropped from the guide plate is evenly scattered in the combustion chamber through the coal scattering mechanism to ensure that the coal can be fully burned. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 It is a schematic diagram of the three-dimensional structure of the present invention; Figure 2 is a first cross-sectional view of the present invention; Figure 3 for Figure 2 A schematic diagram of the enlarged structure of the present invention; Figure 4 is a second cross-sectional view of the present invention; Figure 5 for Figure 4 A schematic diagram of the enlarged structure of position B of the present invention; 1. Limiting mechanism; 101. Positioning frame; 102. First multi-stage electric telescopic rod; 103. Contact plate; 2. Coal anti-blocking mechanism; 201. Fixed block; 202. Transmission plate; 203. Toggle plate; 204. Servo motor; 205. Bearing; 206. Gear ring; 207. Motor gear; 208. Transmission rod; 3. Guide plate; 4. Second multi-stage electric telescopic rod; 5. Coal bulking mechanism; 501. Push rod; 502. Fixed rod; 503. Connecting plate; 504. High temperature resistant cloth; 505. First rotating joint; 506. Spring; 507. Second rotating joint; 508. First annular transmission plate; 509. Second annular transmission plate; 510. First semicircular protrusion; 511. Second semicircular protrusion; 512. Limiting block; 6. High temperature resistant temperature detection needle; 7. High temperature resistant connecting rod. DETAILED DESCRIPTION

[0016] The present invention can be explained in detail by the following examples, and the purpose of disclosing the present invention is to protect all technical improvements within the scope of the present invention.

[0017] Combined with Figures 1 - 5The method for predicting the capacity of an online thermal power unit based on a deep neural network comprises a limiting mechanism 1, the regulating end of the limiting mechanism 1 is fixedly connected with a second multi-stage electric telescopic rod 4 arranged equidistantly, and the telescopic end of the second multi-stage electric telescopic rod 4 is connected to a high-temperature resistant temperature detection needle 6 through a high-temperature resistant connecting rod 7, the insertion depth of each high-temperature resistant temperature detection needle 6 is controlled by the second multi-stage electric telescopic rod 4 arranged equidistantly, and the coal combustion state at different depths is detected by each high-temperature resistant temperature detection needle 6, all the electrical equipment used in the method for predicting the capacity of an online thermal power unit based on a deep neural network are connected to an external control device, and the high-temperature resistant temperature detection needle 6 will transmit the detected data to the external control device during the temperature measurement process for the staff to analyze and predict, the feed end of the limiting mechanism 1 is fixedly connected with a guide plate 3, and a coal anti-blocking mechanism 2 and a coal bulking mechanism 5 are installed in the limiting mechanism 1, the toggle end of the coal anti-blocking mechanism 2 is in contact with the inner wall of the guide plate 3, and the rotating end of the coal anti-blocking mechanism 2 is in contact with the driving end of the coal bulking mechanism 5.

[0018] The limiting mechanism 1 includes a positioning frame 101, a first multi-stage electric telescopic rod 102 and a contact plate 103. The outer wall of the positioning frame 101 is fixedly connected with the first multi-stage electric telescopic rods 102 arranged equidistantly, and the telescopic end of the first multi-stage electric telescopic rod 102 is fixedly connected with the contact plate 103. The positioning frame 101 is installed with a coal anti-blocking mechanism 2 and a coal bulking mechanism 5. The diameter of the first multi-stage electric telescopic rod 102 in the contracted state is smaller than the diameter of the guide plate 3, so as to prevent the first multi-stage electric telescopic rod 102 from being too long and hindering the limiting mechanism 1 from entering the combustion chamber.

[0019] A second multi-stage electric telescopic rod 4 is fixedly connected to each telescopic rod of the first multi-stage electric telescopic rod 102. When the first multi-stage electric telescopic rod 102 is extended, it drives each second multi-stage electric telescopic rod 4 to move, so that the second multi-stage electric telescopic rods 4 are evenly distributed in the combustion chamber.

[0020] The coal anti-blocking mechanism 2 includes a fixed block 201, a transmission plate 202, a toggle plate 203, a servo motor 204, a bearing 205, a gear ring 206, a motor gear 207, and a transmission rod 208. The fixed blocks 201 are arranged equidistantly on the inner wall of the positioning frame 101 and are fixedly connected. Bearings 205 are fixedly connected between the fixed blocks 201. A transmission plate 202 is fixedly connected to the rotating end of the bearing 205. Transmission rods 208 arranged equidistantly are fixedly connected to the transmission plate 202. A toggle plate 203 is fixedly connected to the transmission rod 208. One side of the toggle plate 203 is in contact with the inner wall of the diversion plate 3. A servo motor 204 is fixedly connected to one of the fixed blocks 201. The servo motor 204 is connected to the motor gear 207 through a motor shaft. The gear ring 206 is located on the outer wall of the transmission plate 202 and is fixedly connected. The gear ring 206 corresponds to the position of the motor gear 207 and is meshed and connected.

[0021] The coal bulk material mechanism 5 includes a push rod 501, a fixed rod 502, a first rotating joint 505, and a limit block 512. The fixed rods 502 are arranged equidistantly at the bottom end of the positioning frame 101 and are fixedly connected. The bottom end of the fixed rod 502 is connected to the turning plate through a first rotating joint 505. The limit blocks 512 are arranged equidistantly on the inner wall of the positioning frame 101 and are fixedly connected. A push rod 501 is slidably connected to the limit block 512. The upper and lower ends of the push rod 501 are respectively connected to the turning plate through a transmission component.

[0022] The transmission component includes a first annular transmission plate 508, a second annular transmission plate 509, a first semi-circular protrusion 510, and a second semi-circular protrusion 511. The second annular transmission plate 509 is located on the outer wall of the transmission plate 202 and is fixedly connected. Second semi-circular protrusions 511 arranged equidistantly are fixedly connected to the lower surface of the second annular transmission plate 509. The first annular transmission plate 508 is located at the top end of the push rod 501 and is fixedly connected. First semi-circular protrusions 510 arranged equidistantly are fixedly connected to the upper surface of the first annular transmission plate 508. The position of the first semi-circular protrusion 510 corresponds to the position of the second semi-circular protrusion 511 and is in contact connection.

[0023] The bottom end of the push rod 501 is connected to the turning plate through a second rotating joint 507.

[0024] The turning plate includes a connecting plate 503 and a high-temperature resistant fabric 504. The connecting plates 503 are respectively located on the rotating ends of the first rotating joints 505 arranged equidistantly and are fixedly connected. The high-temperature resistant fabric 504 is fixedly connected between the connecting plates 503. A sliding groove is provided on the connecting plate 503. The rotating end of the second rotating joint 507 is slidably connected in the sliding groove. The high-temperature resistant fabric 504 has a certain stretchability.

[0025] A spring 506 is fixedly connected to the limiting block 512, and one end of the spring 506 is fixedly connected to the lower surface of the first annular transmission plate 508. The position of the spring 506 corresponds to and sleeves the position of the push rod 501, and the first annular transmission plate 508 is driven by the spring 506 to reset.

[0026] When the online unit capacity prediction method for thermal power based on a deep neural network is in use, the staff puts the positioning frame 101 into the combustion chamber through the coal inlet of the combustion chamber, and starts the first multi-stage electric telescopic rod 102 on the positioning frame 101 through an external control device, so that the first multi-stage electric telescopic rod 102 extends, and the contact plate 103 on the first multi-stage electric telescopic rod 102 contacts the inner cavity wall of the combustion chamber to fix the position of the positioning frame 101. Each section of the first multi-stage electric telescopic rod 102 drives the respective second multi-stage electric telescopic rods 4 to move during the extension process. Since the length of each section of the first multi-stage electric telescopic rod 102 is equal, the second multi-stage electric telescopic rods 4 are evenly distributed in the combustion chamber. The high-temperature resistant temperature detection needles 6 are inserted into different depths of the coal pile through the respective second multi-stage electric telescopic rods 4. The combustion states of the coal at different depths are detected by the high-temperature resistant temperature detection needles 6, and the detection data is transmitted to the external control device for the staff to analyze and predict. The servo motor 204 is started through the external control device. The servo motor 204 drives the transmission plate 202 fixed with the gear ring 206 to rotate through the motor gear 207. During the rotation of the transmission plate 202, the dial plate 203 is driven to move through the transmission rod 208. The coal on the guide plate 3 is dialed by the dial plate 203 to prevent the coal from blocking the discharge port of the guide plate 3. During the rotation of the transmission plate 202, the second annular transmission plate 509 fixed with the second semi-circular protrusion 511 is driven to rotate. The first annular transmission plate 508 fixed with the first semi-circular protrusion 510 is pushed down by the second annular transmission plate 509. When the second semi-circular protrusion 511 disengages from the first semi-circular protrusion 510, the first annular transmission plate 508 is pushed to reset by the spring 506, so that the push rod 501 moves up and down reciprocally. One end of the connecting plate 503 is pushed to tilt up and down during the up and down reciprocating movement of the push rod 501. The coal is discharged from the outer edge and the middle hole respectively during the tilting up and down process of the connecting plate 503. Various angles will appear during the movement, and the coal can be evenly scattered into the combustion chamber to prevent the coal from piling up and affecting the combustion state of the coal.

[0027] The parts not detailed in the present invention are prior arts. Although the present invention has been specifically shown and described in conjunction with the preferred embodiments, there are many methods and ways to specifically implement this technical solution. The above is only the preferred embodiment of the present invention. However, those skilled in the art should understand that various changes can be made to the present invention in terms of form and details without departing from the spirit and scope of the present invention defined by the appended claims, and all such changes are within the protection scope of the present invention.

Claims

1. A method for predicting the online unit capacity of thermal power based on a deep neural network, including a limiting mechanism, the limiting mechanism is composed of a positioning frame, a first multi-stage electric telescopic rod and a contact plate, and is characterized in that: The outer wall of the positioning frame is fixedly connected to the first multi-stage electric telescopic rods arranged equidistantly, and the telescopic ends of the first multi-stage electric telescopic rods are fixedly connected to the contact plates. The positioning frame is equipped with a coal anti-blocking mechanism and a coal dispersing mechanism. The steps of the prediction method are as follows: S1. The staff puts the positioning frame into the combustion chamber through the coal inlet of the combustion chamber; S2, controlling the first multi-stage electric telescopic rod on the positioning frame to extend into the combustion chamber through an external control device, so that the contact plate on the first multi-stage electric telescopic rod contacts the inner wall of the combustion chamber; S3, each section of the first multi-stage electric telescopic rod will drive each second multi-stage electric telescopic rod to move during the extension process, and the second multi-stage electric telescopic rods will be evenly distributed in the combustion chamber; S4. The high-temperature resistant temperature detection needle is inserted into different depths of the coal pile through each second multi-stage electric telescopic rod. The high-temperature resistant temperature detection detects the combustion state of the coal at different depths, and transmits the detection data to the external control device for analysis and prediction by the staff.

2. The method for online unit capacity prediction of thermal power based on a deep neural network according to claim 1, characterized in that: A second multi-stage electric telescopic rod arranged equidistantly is fixedly connected to the adjusting end of the limit mechanism, and the telescopic end of the second multi-stage electric telescopic rod is connected to a high-temperature resistant temperature detection needle through a high-temperature resistant connecting rod, and the insertion depth of each high-temperature resistant temperature detection needle is controlled by the second multi-stage electric telescopic rod arranged equidistantly, and the coal combustion state at different depths is detected by each high-temperature resistant temperature detection. A guide plate is fixedly connected to the feeding end of the limit mechanism, and a coal anti-blocking mechanism and a coal bulking mechanism are installed in the limit mechanism, the toggle end of the coal anti-blocking mechanism is in contact with the inner wall of the guide plate, and the rotating end of the coal anti-blocking mechanism is in contact with the driving end of the coal bulking mechanism.

3. The method for online unit capacity prediction of thermal power based on a deep neural network according to claim 2, wherein: A second multi-stage electric telescopic rod is fixedly connected to each telescopic rod of the first multi-stage electric telescopic rod. When the first multi-stage electric telescopic rod is extended, it drives each second multi-stage electric telescopic rod to move, so that the second multi-stage electric telescopic rods are evenly distributed in the combustion chamber.

4. The method for online unit capacity prediction of thermal power based on a deep neural network according to claim 1, wherein: The coal anti-blocking mechanism includes a fixed block, a transmission plate, a toggle plate, a servo motor, a bearing, a gear ring, a motor gear and a transmission rod. The fixed blocks are equidistantly arranged and fixedly connected to the inner wall of the positioning frame, and the bearings are fixedly connected between the fixed blocks. The rotating end of the bearing is fixedly connected to a transmission plate, and the transmission plate is fixedly connected to transmission rods arranged equidistantly. The transmission rod is fixedly connected to a toggle plate, and one side of the toggle plate is in contact with the inner wall of the guide plate. A servo motor is fixedly connected to one of the fixed blocks, and the servo motor is connected to the motor gear through a motor shaft. The gear ring is located on the outer wall of the transmission plate and is fixedly connected, and the position of the gear ring corresponds to that of the motor gear and they are meshed.

5. The online unit capacity prediction method for thermal power generation based on a deep neural network according to claim 1, characterized in that: The coal bulk material mechanism includes a push rod, a fixed rod, a first rotating joint, and a limit block. The fixed rods are arranged equidistantly at the bottom end of the positioning frame and fixedly connected, and the bottom end of the fixed rod is connected to the turning plate through the first rotating joint. The limit blocks are arranged equidistantly on the inner wall of the positioning frame and fixedly connected, and the push rod is slidably connected to the limit blocks. The upper and lower ends of the push rod are respectively connected to the turning plate through a transmission component.

6. The online unit capacity prediction method for thermal power based on a deep neural network according to claim 5, characterized in that: The transmission component includes a first annular transmission plate, a second annular transmission plate, a first semi-circular protrusion, and a second semi-circular protrusion. The second annular transmission plate is located on the outer wall of the transmission plate and fixedly connected, and the lower surface of the second annular transmission plate is fixedly connected with equidistantly arranged second semi-circular protrusions. The first annular transmission plate is located at the top end of the push rod and fixedly connected, and the upper surface of the first annular transmission plate is fixedly connected with equidistantly arranged first semi-circular protrusions. The positions of the first semi-circular protrusions correspond to and are in contact connection with the positions of the second semi-circular protrusions.

7. The method for online unit capacity prediction of thermal power based on a deep neural network according to claim 5, characterized in that: The bottom end of the push rod is connected to the turning plate through a second rotating joint.

8. The method for online unit capacity prediction of thermal power based on a deep neural network according to claim 5, characterized in that: The turning plate includes a connecting plate and a high-temperature resistant fabric. The connecting plates are respectively located at the rotating ends of the equidistantly arranged first rotating joints and fixedly connected, and a high-temperature resistant fabric is fixedly connected between the connecting plates. The connecting plate is provided with a sliding groove, and the rotating end of the second rotating joint is slidably connected in the sliding groove.

9. The method for online unit capacity prediction of thermal power based on a deep neural network according to claim 5, characterized in that: A spring is fixedly connected to the limit block, and one end of the spring is fixedly connected to the lower surface of the first annular transmission plate. The position of the spring corresponds to and sleeves the push rod.

10. The method for online unit capacity prediction of thermal power based on a deep neural network according to claim 9, wherein: A gear ring is fixedly provided on the transmission plate. The transmission plate is driven by the gear of the servo motor to drive the gear ring to rotate the transmission plate. During the rotation of the transmission plate, the transmission rod drives the dialing plate to move, and the coal on the guide plate is dialed by the dialing plate to prevent the coal from blocking the discharge port of the guide plate.

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