Stop valve

Abstract

The invention relates to the field of stop valves, in particular to a stop valve which comprises a valve body, a partition plate, a valve rod and a valve clack, the valve body is provided with a flow channel, the partition plate is fixedly connected to the inner wall of the flow channel and divides the flow channel into a liquid inlet cavity and a liquid outlet cavity, the partition plate is provided with a communication port, the communication port is communicated with the liquid inlet cavity and the liquid outlet cavity, and the outer wall of the valve body is provided with a control port. The control port communicates with the liquid outlet cavity, the control port and the communicating port are coaxially arranged, the valve rod is slidably connected to the inner wall of the control port, the valve clack is coaxially and fixedly connected to the end, facing the partition plate, of the valve rod, a sealing face is coaxially arranged on the outer wall of the valve clack, the diameter of the sealing face is decreased along with the distance from the valve rod, and the sealing face is used for abutting against the inner wall of the communicating port; the valve further comprises a sealing air bag and an elastic rubber ring, a sealing groove is coaxially formed in the outer wall of the valve clack, the sealing air bag is embedded in the sealing groove, and the elastic rubber ring is arranged on the periphery of the sealing air bag in a sleeving mode. The elastic rubber ring abuts against the inner wall of the communicating opening, and the sealing air bag enables the elastic rubber ring to abut against the inner wall of the communicating opening in a self-adaptive mode.

Description

Technical Field

[0001] This application relates to the field of globe valves, and particularly to a globe valve. Background Art

[0002] There are a wide variety of globe valves widely used in the current market, mainly including straight-through type, angle type, three-way type and other forms. These valves are very common in industrial production and are mainly used to control the flow direction and flow rate of the medium in the pipeline.

[0003] However, the existing globe valves generally have problems such as poor sealing performance and short service life, resulting in frequent maintenance or even replacement, increasing the operating costs of enterprises. In particular, when impurities in the medium adhere to the surface of the valve flap, the valve flap and the valve body cannot fit tightly, and the fluid is likely to leak from the gap, affecting the sealing performance of the globe valve. Summary of the Invention

[0004] In order to improve the sealing performance of the globe valve, this application provides a globe valve.

[0005] The globe valve provided by this application adopts the following technical solutions: A globe valve includes a valve body, a partition plate, a valve stem and a valve flap. The valve body is provided with a flow channel. The partition plate is fixedly connected to the inner wall of the flow channel. The partition plate divides the flow channel into a liquid inlet chamber and a liquid outlet chamber. The partition plate is provided with a communication port that communicates the liquid inlet chamber and the liquid outlet chamber. The outer wall of the valve body is provided with a control port that communicates with the liquid outlet chamber. The control port and the communication port are coaxially arranged. The valve stem is slidably connected to the inner wall of the control port. The valve flap is coaxially and fixedly connected to one end of the valve stem facing the partition plate. The outer wall of the valve flap is coaxially provided with a sealing surface, and the diameter of the sealing surface decreases as it is farther away from the valve stem. It further includes a sealing airbag (71) and an elastic rubber ring (78). The outer wall of the valve flap (6) is coaxially provided with a sealing groove (62). The sealing airbag (71) is embedded in the sealing groove (62). The elastic rubber ring (78) is sleeved on the outer periphery of the sealing airbag (71). The outer wall of the sealing airbag (71) abuts against the inner wall of the elastic rubber ring (78). The outer wall of the elastic rubber ring (78) is used to abut against the inner wall of the communication port (21).

[0006] By adopting the above technical solutions, the sealing surface facilitates the sealing between the valve flap and the partition plate, improving the sealing performance of the globe valve. The valve stem slides to drive the valve flap to control the opening and closing of the communication port. The liquid flows from the liquid inlet chamber through the communication port and then is discharged from the liquid outlet chamber. The elastic rubber ring abuts against the inner wall of the communication port, and the sealing airbag enables the elastic rubber ring to adaptively abut tightly against the inner wall of the communication port, further improving the sealing performance between the valve flap and the partition plate, so that when the globe valve is closed, the liquid is not easily passed through the communication port.

[0007] Preferably, it further includes a squeezing airbag. An installation groove is provided on the outer wall of the valve flap. The valve flap is provided with an air passage. One end of the air passage communicates with the bottom of the installation groove, and the other end of the air passage communicates with the bottom of the sealing groove. The squeezing airbag is embedded in the installation groove. The squeezing airbag is provided with a squeezing nozzle, and the sealing airbag is provided with a sealing nozzle. Both the squeezing nozzle and the sealing nozzle are coaxially and fixedly connected to the inner wall of the air passage.

[0008] By adopting the above technical solution, when the squeezing airbag is squeezed and shrunk, the sealing airbag will be inflated at the same time, improving the sealing performance between the sealing airbag and the inner wall of the communication port, reducing the passage of liquid through the communication building when the valve flap is closed, and improving the sealing performance of the stop valve.

[0009] Preferably, it further includes a squeezing block, a rubber pad and a butting column. The installation groove is arranged on one side of the sealing groove close to the valve stem. The squeezing block is arranged on the side of the squeezing airbag away from the air passage. The squeezing block is slidably connected to the groove wall of the installation groove. One end of the squeezing block away from the squeezing airbag is provided with a guiding surface, and the distance from the guiding surface to the sealing surface decreases as it approaches the valve stem. The rubber pad is slidably attached to the sealing surface. One end of the rubber pad away from the valve stem is used to butt against the partition plate. One end of the butting column is fixedly connected to the rubber pad, and the other end of the butting column butts against the guiding surface.

[0010] By adopting the above technical solution, when the valve flap approaches the partition plate, the rubber pad butts against the partition plate. The sliding of the rubber pad causes the butting column to slide synchronously, pushing the squeezing block to slide and squeeze the squeezing airbag, further improving the sealing performance between the sealing airbag and the inner wall of the communication port. At the same time, during the sliding process of the rubber pad, impurities on the surface of the sealing surface are cleaned, reducing the influence of adhered impurities on the sealing surface on the sealing performance of the stop valve.

[0011] Preferably, it further includes an elastic band. There are multiple installation grooves, and the multiple installation grooves are evenly spaced around the axis of the valve flap. There are multiple rubber pads, and the rubber pads are arranged in one-to-one correspondence with the installation grooves. The rubber pads cover the openings of the installation grooves. There are multiple elastic bands, and the elastic bands are arranged between adjacent rubber pads. Both ends of the elastic band are respectively fixedly connected to the two rubber pads, and the elastic band is slidably connected to the sealing surface.

[0012] By adopting the above technical solution, the multiple rubber pads and the multiple elastic bands jointly tighten the valve flap, enabling the rubber pads to closely adhere to the sealing surface and move, improving the cleaning quality of the sealing surface.

[0013] Preferably, it further includes a rotating column, a scraping plate and a scraping blade. One end of the valve flap facing the communication port is coaxially provided with a rotating port. The rotating column is coaxially and rotatably connected to the inner wall of the rotating port. One end of the scraping plate is fixedly connected to the outer wall of the rotating column. The other end of the scraping plate is connected to the scraping blade. The end of the scraping blade away from the scraping plate is used to abut against the rubber pad. The scraping plate abuts against the end face of the valve flap facing the communication port, and the scraping blade abuts against the sealing surface.

[0014] By adopting the above technical solution, the rotation of the rotating column drives the movement of the ancient plate, so that the scraping plate and the scraping blade clean the valve flap, reducing the probability of impurities adhering to the valve flap and improving the sealing performance of the globe valve.

[0015] Preferably, it further includes a gear, a sliding column and a rack. A sliding groove is provided at the bottom of the installation groove. The valve flap is provided with an installation cavity. The sliding groove communicates with the installation cavity. The gear is arranged in the installation cavity. The gear is coaxially and fixedly connected to the rotating column. The sliding column is slidably connected to the wall of the sliding groove. One end of the sliding column is fixedly connected to the extrusion block. The other end of the sliding column is fixedly connected to the rack. The rack meshes with the gear.

[0016] By adopting the above technical solution, while the extrusion block moves, it drives the sliding column to move. The rotation of the rotating column is driven by the gear and the rack, so that the scraping plate and the scraping blade clean the valve flap, improving the sealing performance of the globe valve.

[0017] Preferably, there are multiple scraping plates, and the multiple scraping plates are evenly spaced around the rotation axis of the rotating column. There are multiple scraping blades, and the scraping blades are arranged in one-to-one correspondence with the scraping plates.

[0018] By adopting the above technical solution, the rotating column can clean the entire valve flap by rotating a small angle, improving the cleaning efficiency.

[0019] In summary, the present application includes at least one of the following beneficial technical effects: The sealing surface facilitates the sealing between the valve flap and the partition plate, improving the sealing performance of the globe valve. The valve stem slides to drive the valve flap to control the on-off of the communication port. The liquid flows from the liquid inlet cavity through the communication port and then is discharged from the liquid outlet cavity. The elastic rubber ring abuts against the inner wall of the communication port. The sealing airbag enables the elastic rubber ring to adaptively abut against the inner wall of the communication port, further improving the sealing performance between the valve flap and the partition plate, so that when the globe valve is closed, the liquid is not easily passed through the communication port; When the valve flap approaches the partition plate, the rubber pad abuts against the partition plate. The sliding of the rubber pad causes the abutting column to slide synchronously, pushing the extrusion block to slide and squeeze the extrusion airbag, further improving the sealing performance between the sealing airbag and the inner wall of the communication port. At the same time, during the sliding process of the rubber pad, the impurities on the surface of the sealing surface are cleaned, reducing the influence of the adhesion of impurities on the sealing surface on the sealing performance of the globe valve; While the extrusion block moves, it drives the sliding column to move. Through the gear and rack, it drives the rotating column to rotate, so that the scraper and the scraping blade clean the valve flap, improving the sealing performance of the globe valve. Brief Description of the Drawings

[0020] Figure 1 It is a schematic diagram of the overall structure of the globe valve.

[0021] Figure 2 is Figure 1 The enlarged view of part A in

[0022] Figure 3 is Figure 1 The enlarged view of part B in

[0023] Figure 4 is Figure 1 The enlarged view of part C in

[0024] Description of the Reference Numerals: 1. Valve body; 11. Flow channel; 12. Liquid inlet chamber; 13. Liquid outlet chamber; 14. Control port; 141. Placing groove; 2. Partition plate; 21. Communication port; 3. Valve stem; 4. Stuffing box; 5. Sealing ring; 6. Valve flap; 61. Sealing surface; 62. Sealing groove; 63. Mounting groove; 631. Sliding groove; 64. Air passage; 65. Rotating port; 66. Mounting cavity; 7. Sealing assembly; 71. Sealing airbag; 711. Sealing bag nozzle; 72. Extrusion airbag; 721. Extrusion bag nozzle; 73. Extrusion block; 731. Guide surface; 74. Rubber pad; 75. Abutted column; 76. Elastic cord; 77. Scraper; 78. Elastic rubber ring; 8. Cleaning assembly; 81. Rotating column; 82. Scraper; 83. Scraping blade; 84. Gear; 85. Sliding column; 86. Rack. Detailed Description of the Preferred Embodiment

[0025] The following further elaborates on this application in conjunction with the attached Figures 1-4 drawings for a more detailed explanation.

[0026] The embodiment of this application discloses a globe valve. Referring to Figure 1 , the globe valve includes a valve body 1, a partition plate 2, a valve stem 3, a stuffing box 4, a sealing ring 5, a valve flap 6, a sealing assembly 7, and a cleaning assembly 8.

[0027] The valve body 1 is provided with a flow channel 11. The material of the valve body 1 is made of high-strength alloy steel, and the inner wall of the flow channel 11 is smooth and burr-free to ensure the smooth passage of the medium. The partition plate 2 is fixedly connected to the inner wall of the flow channel 11. The partition plate 2 divides the flow channel 11 into a liquid inlet chamber 12 and a liquid outlet chamber 13. The partition plate 2 is provided with a communication port 21, and the communication port 21 communicates with the liquid inlet chamber 12 and the liquid outlet chamber 13. The outer wall of the valve body 1 is provided with a control port 14, and the control port 14 communicates with the liquid outlet chamber 13. The control port 14 and the communication port 21 are coaxially arranged.

[0028] Referring toFigure 1 , the valve stem 3 is slidably connected to the inner wall of the control port 14. The material of the valve stem 3 is made of stainless steel, and the surface of the valve stem 3 is precisely polished to reduce the frictional resistance. A placement groove 141 is coaxially provided on the inner wall of the control port 14, and the stuffing box 4 is embedded in the placement groove 141. The stuffing box 4 includes flexible graphite packing, which effectively prevents external impurities from entering the valve body 1. A sealing ring 5 is provided on the side of the stuffing box 4 close to the flow channel 11. The sealing ring 5 is coaxially fixedly connected to the outer wall of the valve stem 3. The outer wall of the sealing ring 5 abuts against the inner wall of the control port 14. The material of the sealing ring 5 is made of a high-performance rubber material, which can maintain good elasticity under high temperature and high pressure.

[0029] The valve flap 6 is coaxially fixedly connected to one end of the valve stem 3 facing the partition plate 2. A sealing surface 61 is coaxially provided on the outer wall of the valve flap 6. The diameter of the sealing surface 61 decreases as it is farther away from the BP valve stem 3. The sealing surface 61 is used to abut against the inner wall of the communication port 21.

[0030] Refer to Figure 2 and Figure 3 , the sealing assembly 7 includes a sealing airbag 71, an extrusion airbag 72, an extrusion block 73, a rubber pad 74, a butting column 75, an elastic band 76, a scraper 77 and an elastic rubber ring 78.

[0031] Refer to Figure 1 and Figure 2 , a sealing groove 62 is coaxially provided on the outer wall of the valve flap 6. The sealing airbag 71 is embedded in the sealing groove 62. The elastic rubber ring 78 is sleeved on the outer periphery of the sealing airbag 71. The outer wall of the sealing airbag 71 abuts against the inner wall of the elastic rubber ring 78. The outer wall of the elastic rubber ring 78 is used to abut against the inner wall of the communication port 21. An installation groove 63 is provided on the outer wall of the valve flap 6. The installation groove 63 is provided on the side of the sealing groove 62 close to the valve stem 3. The valve flap 6 is provided with an air passage 64. One end of the air passage 64 communicates with the bottom of the installation groove 63, and the other end of the air passage 64 communicates with the bottom of the sealing groove 62. There are multiple installation grooves 63, and the multiple installation grooves 63 are evenly spaced around the axis of the valve flap 6. There are multiple air passages 64, and the air passages 64 are arranged in one-to-one correspondence with the installation grooves 63. The extrusion airbag 72 is embedded in the installation groove 63. The extrusion airbag 72 is provided with an extrusion nozzle 721, and the sealing airbag 71 is provided with a sealing nozzle 711. The extrusion nozzle 721 and the sealing nozzle 711 are both coaxially fixedly connected to the inner wall of the air passage 64.

[0032] The extrusion block 73 is arranged on the side of the extrusion airbag 72 away from the air passage 64. The extrusion block 73 is slidably connected to the groove wall of the installation groove 63. One end of the extrusion block 73 facing away from the extrusion airbag 72 is provided with a guiding surface 731. The guiding surface 731 is set as an inclined surface. The slope of the guiding surface 731 is greater than that of the sealing surface 61. The distance from the guiding surface 731 to the sealing surface 61 decreases as it approaches the valve stem 3. The rubber pad 74 is slidably attached to the sealing surface 61. One end of the rubber pad 74 facing away from the valve stem 3 is used to abut against the partition plate 2. One end of the abutting column 75 is fixedly connected to the rubber pad 74, and the other end of the abutting column 75 abuts against the guiding surface 731. There are multiple rubber pads 74, and the rubber pads 74 are arranged in one-to-one correspondence with the installation grooves 63. The rubber pads 74 cover the notch of the installation groove 63. When the valve flap 6 is away from the communication port 21, the rubber pads 74 cover the sealing groove 62.

[0033] Refer to Figure 2 and Figure 3 There are multiple elastic bands 76. The number of elastic bands 76 is one less than the number of rubber pads 74. The elastic bands 76 are arranged between adjacent rubber pads 74. Both ends of the elastic bands 76 are fixedly connected to two rubber pads 74 respectively. The elastic bands 76 are slidably connected to the sealing surface 61. The scraper 77 is fixedly connected to one end of the elastic band 76 facing the sealing surface 61.

[0034] Refer to Figure 1 and Figure 3 The scraper 77 is arranged at one end of the elastic band 76 close to the communication port 21. There are multiple scrapers 77. The multiple scrapers 77 are evenly spaced along the extending direction of the elastic band 76. Both the scraper 77 and the rubber pad 74 are used to clean the sealing surface 61.

[0035] Refer to Figure 2 and Figure 4 The cleaning assembly 8 includes a rotating column 81, a scraping plate 82, a scraping blade 83, a gear 84, a sliding column 85 and a rack 86.

[0036] Refer to Figure 1 and Figure 4 One end of the valve flap 6 facing the communication port 21 is coaxially provided with a rotating port 65. The rotating column 81 is coaxially and rotatably connected to the inner wall of the rotating port 65.

[0037] Refer to Figure 2 and Figure 4 One end of the scraping plate 82 is fixedly connected to the outer wall of the rotating column 81. The other end of the scraping plate 82 is fixedly connected to the scraping blade 83. One end of the scraping blade 83 away from the scraping plate 82 is used to abut against the rubber pad 74. The scraping plate 82 abuts against the end face of the valve flap 6. The scraping blade 83 abuts against the sealing surface 61. There are multiple scraping plates 82. The multiple scraping plates 82 are evenly spaced around the rotation axis of the rotating column 81. There are multiple scraping blades 83. The scraping blades 83 are arranged in one-to-one correspondence with the scraping plates 82.

[0038] A sliding groove 631 is provided at the bottom of one of the mounting grooves 63. The valve flap 6 is provided with a mounting cavity 66. The sliding groove 631 and the rotating port 65 communicate with the mounting cavity 66. The gear 84 is arranged in the mounting cavity 66. The gear 84 is coaxially and fixedly connected to the rotating column 81. The sliding column 85 is slidably connected to the wall of the sliding groove 631. One end of the sliding column 85 is fixedly connected to the extrusion block 73. The other end of the sliding column 85 is fixedly connected to the rack 86. The rack 86 meshes with the gear 84.

[0039] The implementation principle of a globe valve in an embodiment of the present application is as follows: The liquid passes from the liquid inlet cavity 12 through the communication port 21 and is discharged from the liquid outlet cavity 13. The valve stem 3 slides to drive the valve flap 6 to move, controlling the on-off of the communication port 21. When the valve flap 6 approaches the communication port 21, the partition plate 2 abuts against the rubber pad 74, causing the rubber pad 74 to move towards the valve stem 3. The abutting column 75 abuts against the guiding surface 731, causing the extrusion block 73 to move. The extrusion block 73 causes the extrusion airbag 72 to contract and the sealing airbag 71 to expand. The elastic rubber ring 78 abuts against the inner wall of the communication port 21 to improve the sealing performance. The extrusion block 73 causes the sliding column 85 to slide and the rotating column 81 to rotate. The scraping plate 82 and the scraping blade 83 jointly clean the valve flap 6. When the valve flap 6 moves away from the communication port 21, the elastic band 76 causes the rubber pad 74 to move away from the valve stem 3. The scraping knife 77 and the rubber pad 74 jointly clean the outer wall of the valve flap 6, pushing the impurities to the side of the sealing groove 62 away from the mounting groove 63. The rotating column 81 rotates, causing the scraping plate 82 and the scraping blade 83 to rotate in the reverse direction to clean the valve flap 6. Finally, the scraping blade 83 can abut against the rubber pad 74 to complete the overall cleaning of the valve flap 6.

[0040] The above are all the preferred embodiments of the present application. The protection scope of the present application is not limited thereby. Therefore, all equivalent changes made according to the structure, shape, and principle of the present application should be covered within the protection scope of the present application.

Claims

1. A stop valve, characterized in that: The invention comprises a valve body (1), a partition plate (2), a valve stem (3) and a valve flap (6); the valve body (1) is provided with a flow channel (11); the partition plate (2) is fixedly connected to the inner wall of the flow channel (11); the partition plate (2) divides the flow channel (11) into a liquid inlet chamber (12) and a liquid outlet chamber (13); the partition plate (2) is provided with a communication port (21); the communication port (21) is connected to the liquid inlet chamber (12) and the liquid outlet chamber (13); the outer wall of the valve body (1) is provided with a control port (14); the control port (14) is connected to the liquid outlet chamber (13); the control port (14) and the communication port (21) are coaxially arranged; the valve stem (3) is slidably connected to the control port (14); The valve flap (6) is coaxially fixedly connected to an end of the valve stem (3) facing the partition plate (2), and the outer wall of the valve flap (6) is coaxially provided with a sealing surface (61), and the diameter of the sealing surface (61) decreases as it moves away from the valve stem (3); it also includes a sealing airbag (71) and an elastic rubber ring (78), the outer wall of the valve flap (6) is coaxially provided with a sealing groove (62), the sealing airbag (71) is embedded in the sealing groove (62), the elastic rubber ring (78) is sleeved on the outer periphery of the sealing airbag (71), the outer wall of the sealing airbag (71) abuts against the inner wall of the elastic rubber ring (78), and the outer wall of the elastic rubber ring (78) is used to abut against the inner wall of the connecting port (21).

2. The stop valve according to claim 1, characterized in that: It also comprises an extrusion airbag (72), the outer wall of the valve flap (6) is provided with a mounting groove (63), the valve flap (6) is provided with an air channel (64), one end of the air channel (64) is connected to the groove bottom of the mounting groove (63), and the other end of the air channel (64) is connected to the groove bottom of the sealing groove (62), the extrusion airbag (72) is embedded in the mounting groove (63), the extrusion airbag (72) is provided with an extrusion bag mouth (721), and the sealing airbag (71) is provided with a sealing bag mouth (711), and the extrusion bag mouth (721) and the sealing bag mouth (711) are both coaxially fixedly connected to the inner wall of the airchannel (64).

3. The stop valve according to claim 2, characterized in that: The device further comprises an extrusion block (73), a rubber pad (74) and an abutment column (75); the mounting groove (63) is arranged on a side of the sealing groove (62) close to the valve stem (3); the extrusion block (73) is arranged on a side of the extrusion airbag (72) away from the air passage (64); the extrusion block (73) is slidably connected to the groove wall of the mounting groove (63); an end of the extrusion block (73) facing away from the extrusion airbag (72) is provided with a guide surface (731); the distance between the guide surface (731) and the sealing surface (61) decreases as it approaches the valve stem (3); the rubber pad (74) is slidably fitted to the sealing surface (61); an end of the rubber pad (74) facing away from the valve stem (3) is used to abut the partition plate (2); one end of the abutment column (75) is fixedly connected to the rubber pad (74); and the other end of the abutment column (75) abuts the guide surface (731).

4. The stop valve according to claim 3, characterized in that: It also includes an elastic band (76), a plurality of the mounting grooves (63) are provided, and the plurality of the mounting grooves (63) are evenly spaced around the axis of the valve disc (6), a plurality of the rubber pads (74) are provided, and the rubber pads (74) are arranged in a one-to-one correspondence with the mounting grooves (63), and the rubber pads (74) cover the notches of the mounting grooves (63), and a plurality of the elastic bands (76) are provided, and the elastic bands (76) are arranged between two adjacent rubber pads (74), and the two ends of the elastic band (76) are respectively fixedly connected to the two rubber pads (74), and the elastic band (76) is slidably connected to the sealing surface (61).

5. The stop valve according to claim 3, characterized in that: It also comprises a rotating column (81), a scraper (82) and a scraper blade (83); one end of the valve flap (6) facing the connecting port (21) is coaxially provided with a rotating port (65); the rotating column (81) is coaxially rotatably connected to the inner wall of the rotating port (65); one end of the scraper blade (82) is fixedly connected to the outer wall of the rotating column (81); the other end of the scraper blade (82) is connected to the scraper blade (83); the end of the scraper blade (83) away from the scraper blade (82) is used to abut against the rubber pad (74); the scraper blade (82) abuts against the end surface of the valve flap (6) facing the connecting port (21); and the scraper blade (83) abuts against the sealing surface (61).

6. The stop valve according to claim 5, characterized in that: It also includes a gear (84), a sliding column (85) and a rack (86); the bottom of the mounting groove (63) is provided with a sliding groove (631); the valve flap (6) is provided with a mounting cavity (66); the sliding groove (631) is communicated with the mounting cavity (66); the gear (84) is arranged in the mounting cavity (66); the gear (84) is coaxially fixedly connected to the rotating column (81); the sliding column (85) is slidably connected to the groove wall of the sliding groove (631); one end of the sliding column (85) is fixedly connected to the extrusion block (73); the other end of the sliding column (85) is fixedly connected to the rack (86); and the rack (86) is meshed with the gear (84).

7. The stop valve according to claim 6, characterized in that: A plurality of the scrapers (82) are provided, and the plurality of the scrapers (82) are evenly spaced around the rotation axis of the rotating column (81); a plurality of the scrapers (83) are provided, and the scrapers (83) are arranged in one-to-one correspondence with the scrapers (82).

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