Plastic particle vertical conveying pipe control structure capable of automatically controlling opening and closing of bifurcated runner

Abstract

A plastic particle vertical conveying pipe control structure capable of automatically controlling opening and closing of forked flow channels comprises a vertical conveying pipe located above a material barrel, the lower section of the vertical conveying pipe is forked into the two forked flow channels, and the two forked flow channels are a material suction channel and a material returning channel respectively; the material returning channel is provided with a one-way valve plate; a hollow valve block is rotatably mounted in the vertical conveying pipe, the extension direction of a rotating shaft of the hollow valve block is longitudinal, and the central axis of the rotating shaft of the hollow valve block is located on the top edge of the partition wall; the hollow valve block comprises three valve plates which are connected together to form a prism shape, the three valve plates are respectively a first valve plate, a second valve plate and a third valve plate, and a third ridge line is close to and parallel to a rotating shaft of the hollow valve block; the third ridge is located at the lowest point of the whole hollow valve block, and the first ridge is closer to the left than the second ridge; ventilation nets are arranged in the middle of the second valve plate and the middle of the third valve plate respectively. According to the invention, the on-off state of the bifurcated flow channel can be automatically controlled in the material sucking and returning process of the vertical material conveying pipe.

Description

Technical Field

[0001] The present invention belongs to the technical field of plastic production and processing equipment, and particularly relates to a control structure for a vertical plastic granule conveying pipe that automatically controls the on-off of a bifurcated flow channel. Background Art

[0002] The raw material for plastic products is plastic granules. The container for storing plastic granules is generally called a hopper, which is located in the factory storage area. During the production of plastic products, an extruder located in the factory production area melts and extrudes the plastic granules. A hopper is provided above the extruder, and the plastic granules enter the extruder through the discharge port. Before the plastic granules in the hopper above the extruder are exhausted, the hopper needs to be refilled, that is, the plastic granules in the hopper in the storage area are sucked into the hopper of the extruder in the production area by using vacuum negative pressure. This process is called suction feeding or also known as feeding. Usually, the storage area and the production area are far apart, and the horizontal distance between the hopper and the hopper is generally dozens of meters or even longer.

[0003] In addition, during the production process, it is often necessary to change the material (that is, change the variety of plastic granules). At this time, there may still be a large amount of plastic granules of the original variety remaining in the hopper. Therefore, it is necessary to discharge the plastic granules of the original variety from the hopper above the extruder. This process is called discharging or also known as returning the material. To achieve discharging, the traditional method requires a discharging port to be opened at the lower part of the hopper. The discharging port is equipped with a valve. Usually, the valve of the discharging port is in a closed state. During discharging, the valve of the discharging port is opened, and then the accumulated plastic granules in the hopper automatically flow down through the discharging port. The worker uses a bag to catch the plastic granules at the discharging port, and then transfers the bagged plastic granules to the side of the hopper dozens of meters away, and finally pours them into the hopper. This is obviously more laborious.

[0004] To solve this problem, the applicant developed a plastic granule feeding mechanism with a discharging function and applied for an invention patent. The authorized publication number is CN118769512B. The technical solution is characterized in that only one total horizontal conveying pipe dozens of meters long can realize both the feeding and discharging functions, without the need to set up a suction pipe dozens of meters long to transmit power, which not only reduces the number of pipes but also reduces the number of turns of the conveying pipe, facilitating the smoothness of the conveying pipe and making it not easy to be blocked. Figure 1 、 Figure 2As shown. Since the structure of CN118769512B has only one main conveying pipe, when feeding, the suction port of the material pipe needs to be inserted into the plastic granule accumulation in the material bucket 2, and when discharging, the discharge port of the material pipe needs to leave the plastic granule accumulation and be located above the plastic granule accumulation. Therefore, the vertical conveying pipe 8 above the material bucket 2 forms a Y-shaped bifurcation structure, that is, it bifurcates into a discharge channel 72 and a suction channel 41. The lower end pipe orifice of the suction channel 41 is located at the lower part of the material bucket 2, and the lower end pipe orifice 720 of the discharge channel 72 is located above the material bucket 2, and a valve is also provided at the lower end pipe orifice 720 of the discharge channel. In this way, when sucking materials, the valve at the lower end pipe orifice 720 of the discharge channel is closed, the two-way fan 30 starts the air extraction mode to make the hopper 1 form a negative pressure, and the negative pressure is conducted from the downstream section 42 of the suction channel, the horizontal conveying pipe 9, the vertical conveying pipe 8, and the suction channel 41 to the material bucket 2, thereby realizing material suction. The material suction path and direction are as shown in Figure 1 the arrow; when discharging materials, the valve at the lower end pipe orifice 720 of the discharge channel is opened, the two-way fan 30 blows the plastic granules in the hopper 1 towards the upstream section 71 of the discharge channel, then the plastic granules flow horizontally along the horizontal conveying pipe 9, and then the plastic granules flow downward along the vertical conveying pipe 8. When starting to discharge materials, the plastic granules falling from above are divided into two parts. The first part directly falls into the plastic granule accumulation through the discharge channel 72, and the second part falls into the lumen of the suction channel 41 and gradually accumulates in the lumen of the suction channel 41. Until the suction channel 41 is filled with plastic granules, the plastic granules flowing down from the vertical conveying pipe 8 all fall into the plastic granule accumulation through the discharge channel 72. The material discharge path and direction are as shown in Figure 2 the arrow.

[0005] Through practice, the applicant found that the above structure still has the following two aspects to be improved: First, during the material discharge process, the suction channel 41 is filled with plastic granules and also needs to continuously bear the downward impact of the subsequent plastic granule fluid falling from above, making the plastic granules in the suction channel 41 more and more dense, which may cause the plastic granules to block the suction channel 41. After blocking, manual cleaning is required; Second, since the valve at the lower end pipe orifice 720 of the discharge channel is dozens of meters away from the hopper 1, and the operation area for sucking or discharging materials is mainly next to the hopper 1, so before each material suction or discharge, the worker needs to walk dozens of meters from next to the hopper 1 to next to the material bucket 2 to open or close the valve at the lower end pipe orifice 720 of the discharge channel, and then walk back next to the hopper 1 for operation, which is rather troublesome. Summary of the Invention

[0006] The purpose of the present invention is to overcome the above-mentioned drawbacks and provide a control structure for the vertical plastic granule conveying pipe that automatically controls the on-off state of the bifurcated flow channel, which can automatically control the on-off state of the bifurcated flow channel during the material suction and discharge processes of the vertical conveying pipe.

[0007] Its purpose can be achieved according to the following solution: A control structure for a vertical plastic pellet conveying pipe that automatically controls the on-off of a bifurcated flow channel, including a vertical conveying pipe located above a material bucket. The lower section of the vertical conveying pipe bifurcates into two bifurcated flow channels, namely a material suction channel and a material discharge channel. The outlet at the bottom of the material suction channel is located in the lower part of the inner cavity of the material bucket, and the outlet at the bottom of the material discharge channel is located above the material bucket. It is characterized in that the cross-section of the vertical conveying pipe is rectangular. The vertical conveying pipe is provided with a front side wall, a rear side wall, a left side wall, and a right side wall. A partition wall is provided in the center of the inner cavity of the vertical conveying pipe. The partition wall is parallel to the left side wall and the right side wall. The bottom edges of the left half of the front side wall, the left half of the rear side wall, and the left side wall are higher than the bottom edge of the partition wall. The bottom edges of the right half of the front side wall, the right half of the rear side wall, and the right side wall are flush with the bottom edge of the partition wall. The space enclosed by the right half of the front side wall, the right half of the rear side wall, the right side wall, and the partition wall forms the material suction channel, and the space enclosed by the left half of the front side wall, the left half of the rear side wall, the left side wall, and the partition wall forms the material discharge channel. A one-way valve plate is provided in the material discharge channel, and the opening direction of the one-way valve plate is to rotate downward. A hollow valve block is rotatably installed in the vertical conveying pipe. The extending direction of the rotating shaft of the hollow valve block is longitudinal, and the central axis of the rotating shaft of the hollow valve block is located at the top edge of the partition wall. The longitudinal length of the hollow valve block is equivalent to the longitudinal dimension of the pipe cavity of the vertical conveying pipe. The hollow valve block includes three valve plates that are connected together to form a triangular prism shape. The three valve plates are respectively called the first valve plate, the second valve plate, and the third valve plate. The intersection line between the first valve plate and the second valve plate is called the first edge line, the intersection line between the first valve plate and the third valve plate is called the second edge line, and the intersection line between the second valve plate and the third valve plate is called the third edge line. The third edge line is close to and parallel to the rotating shaft of the hollow valve block. The third edge line is located at the lowest point of the entire hollow valve block, and the first edge line is more to the left than the second edge line. Ventilation nets are respectively provided at the middle parts of the second valve plate and the third valve plate. When the first edge line rotates to contact the left side wall, the first valve plate and the left side wall above the first edge line form an acute angle less than 60°, and the center of gravity of the entire hollow valve block is located on the left side of the plane where the partition wall is located and close to the plane where the partition wall is located. When the second edge line rotates to contact the right side wall, the center of gravity of the entire hollow valve block is located on the right side of the plane where the partition wall is located. The first valve plate and the right side wall above the second edge line form an obtuse angle, and the third valve plate and the right side wall below the second edge line form an acute angle.

[0008] A counterweight is provided at the upper right corner of the hollow valve block.

[0009] When the first edge line rotates to contact the left side wall, the horizontal distance between the second edge line and the right side wall is equal to 0.8 - 1.0 times the horizontal width of the material suction channel.

[0010] When the second ridge rotates to contact the right side wall, the lateral distance between the first ridge and the left side wall is equal to 0.8 to 1.0 times the lateral width of the material discharging channel.

[0011] The present invention has the following advantages and effects: First, the present invention can automatically control the on / off state of the bifurcated flow channel during the process of sucking / discharging materials in the vertical material conveying pipe. Specifically, during the material sucking process, the one-way valve piece is sucked upward by negative pressure and remains in the closed position. The first ridge of the hollow valve block automatically keeps in contact with the left side wall of the material conveying pipe, and the material discharging channel is automatically disconnected, preventing external air from entering the material conveying pipe through the bottom port of the material discharging channel to maintain the vacuum degree of the material conveying pipe. A rising channel for the plastic particles to flow upward is formed between the third valve plate of the hollow valve block and the right side wall, and this rising channel faces the material sucking channel to keep the material sucking channel unobstructed, so continuous material sucking can be achieved; during the material discharging process, the second ridge of the hollow valve block automatically keeps in contact with the right side wall of the material conveying pipe, and the hollow valve block disconnects the material sucking channel, preventing the plastic particles from continuously falling into the material sucking channel and continuously impacting the plastic particles inside the material sucking channel, thereby avoiding blockage of the material sucking channel. A descending channel for the plastic particles to flow downward is formed between the second valve plate of the hollow valve block and the left side wall, and this descending channel faces the material discharging channel to keep the material discharging channel unobstructed, so continuous material discharging can be achieved. Second, during the above process, the on / off state of the bifurcated flow channel does not require any manual intervention or any electric mechanism intervention. The whole mechanism is simple and ingenious, avoiding the trouble of workers walking back and forth and eliminating the need to construct a remotely controlled electric control system. Description of the Drawings

[0012] Figure 1 is a schematic diagram of the material sucking path and direction in the structure disclosed in CN118769512B.

[0013] Figure 2 is a schematic diagram of the material discharging path and direction in the structure disclosed in CN118769512B.

[0014] Figure 3 is a schematic diagram of the overall structure of a specific embodiment of the present invention.

[0015] Figure 4 is Figure 3 an enlarged structural schematic diagram of the hollow valve block in

[0016] Figure 5 is Figure 4 a three-dimensional structural schematic diagram of the hollow valve block in

[0017] Figure 6 is Figure 3 a schematic diagram of the D-D cross-section in

[0018] Figure 7 isFigure 3 Schematic diagram of the changed state after the hollow valve block in

[0019] Figure 8 is the overall structural schematic diagram of an automatic feeding and discharging system for plastic pellets applying a specific embodiment of the present invention.

[0020] Figure 9 is the schematic diagram of the first starting state in the material suction process of a specific embodiment of the present invention.

[0021] Figure 10 is Figure 9 the schematic diagram of the changed state after further evolution of the state shown.

[0022] Figure 11 in Figure 10 the schematic diagram of the changed state after further evolution of the state shown, and is also the schematic diagram of the continuous material suction process of a specific embodiment of the present invention.

[0023] Figure 12 is the schematic diagram of the second starting state in the material suction process of a specific embodiment of the present invention.

[0024] Figure 13 is Figure 12 the schematic diagram of the changed state after further evolution of the state shown.

[0025] Figure 14 in Figure 13 the schematic diagram of the changed state after further evolution of the state shown.

[0026] Figure 15 in Figure 14 the schematic diagram of the changed state after further evolution of the state shown, and is also the schematic diagram of the continuous material suction process of a specific embodiment of the present invention.

[0027] Figure 16 is the schematic diagram of the first starting state in the material discharging process of a specific embodiment of the present invention.

[0028] Figure 17 is Figure 16 the schematic diagram of the changed state after further evolution of the state shown, and is also the schematic diagram of the continuous material discharging process of a specific embodiment of the present invention.

[0029] Figure 18 is the schematic diagram of the second starting state in the material discharging process of a specific embodiment of the present invention.

[0030] Figure 19 is Figure 18 the schematic diagram of the changed state after further evolution of the state shown.

[0031] Figure 20 is Figure 19Schematic diagram of the changed state after further evolution of the shown state, and also a schematic diagram of the specific embodiment of the present invention in the continuous material discharging process. Detailed implementation mode

[0032] Figure 3 、 Figure 7 、 Figure 6 A plastic pellet vertical conveying pipe control structure for automatically controlling the on-off of a bifurcated flow channel as shown includes a vertical conveying pipe 8 located above a material bucket 2. The lower section of the vertical conveying pipe 8 bifurcates into two bifurcated flow channels, namely a material suction channel 41 and a material discharging channel 72. The cross-section of the vertical conveying pipe 8 is rectangular. The vertical conveying pipe 8 is provided with a front side wall 81, a rear side wall 82, a left side wall 83, and a right side wall 84. A partition wall 85 is provided in the center of the inner cavity of the vertical conveying pipe 8. The partition wall 85 is parallel to the left side wall 83 and the right side wall 84. The front side wall 81 is divided into a left half part 811 and a right half part 812 of the front side wall. The rear side wall 82 is divided into a left half part 821 and a right half part 822 of the rear side wall. The bottom edges of the left half part 811 of the front side wall, the left half part 821 of the rear side wall, and the left side wall 83 are higher than the bottom edge of the partition wall 85. The bottom edges of the right half part 812 of the front side wall, the right half part 822 of the rear side wall, and the right side wall 84 are flush with the bottom edge of the partition wall 85. The space enclosed by the right half part 812 of the front side wall, the right half part 822 of the rear side wall, the right side wall 84, and the partition wall 85 forms the material suction channel 41. The space enclosed by the left half part 811 of the front side wall, the left half part 821 of the rear side wall, the left side wall 83, and the partition wall 85 forms the material discharging channel 72. The outlet at the bottom end of the material suction channel 41 is located in the lower part of the inner cavity of the material bucket 2. The outlet at the bottom end of the material discharging channel 72 is located above the material bucket 2. The material discharging channel 72 is provided with a check valve plate 5. The check valve plate 5 is provided with a valve plate rotating shaft 50. The extending direction of the valve plate rotating shaft 50 is horizontally longitudinal. The opening direction of the check valve plate 5 is to rotate downward counterclockwise, and the closing direction of the check valve plate 5 is to rotate upward clockwise.

[0033] Figure 3 、 Figure 4 、 Figure 5As shown in the figure, a hollow valve block 6 is rotatably installed inside the vertical feed pipe 8. The extending direction of the rotating shaft 60 of the hollow valve block is longitudinal, and the central axis of the rotating shaft 60 of the hollow valve block is located at the top edge of the partition wall 85; the longitudinal length of the hollow valve block 6 is equivalent to the longitudinal dimension of the cavity of the vertical feed pipe 8; the hollow valve block 6 includes three valve plates, which are respectively called the first valve plate 61, the second valve plate 62, and the third valve plate 63. The three valve plates are connected together to form a triangular prism shape. The intersection line of the first valve plate 61 and the second valve plate 62 is called the first edge line 64, the intersection line of the first valve plate 61 and the third valve plate 63 is called the second edge line 65, and the intersection line of the second valve plate 62 and the third valve plate 63 is called the third edge line 66. A counterweight 69 is provided at the upper right corner of the hollow valve block 6; the third edge line 66 is close to and parallel to the rotating shaft 60 of the hollow valve block; the third edge line 66 is located at the lowest point of the entire hollow valve block 6, and the first edge line 64 is more to the left than the second edge line 65; a first air-permeable net 67 is provided in the middle of the second valve plate 62, and a second air-permeable net 68 is provided in the middle of the third valve plate 63; the mesh holes of the first air-permeable net 67 and the second air-permeable net 68 can allow air to pass through and conduct negative pressure, but cannot allow plastic particles to pass through; When the hollow valve block 6 rotates around its rotating shaft 60 and drives the first edge line 64 to rotate to contact the left side wall 83 of the vertical feed pipe 8, the included angle formed by the first valve plate 61 and the left side wall 83 above the first edge line 64 (such as Figure 7 shown as ∠A in the figure) is an acute angle of 45°. The center of gravity point of the entire hollow valve block 6 (such as Figure 7 shown as point G in the figure) is located on the left side of the plane where the partition wall 85 is located and close to the plane where the partition wall 85 is located. The horizontal distance between the second edge line 65 and the right side wall 84 is equal to 0.9 times the horizontal width of the material suction channel, as shown in Figure 7 , Figure 5 shown; When the hollow valve block 6 rotates around its rotating shaft 60 and drives the second edge line 65 to rotate to contact the right side wall 84 of the vertical feed pipe 8, the center of gravity point of the entire hollow valve block 6 (such as Figure 3 shown as point G in the figure) is located on the right side of the plane where the partition wall 85 is located. The included angle formed by the first valve plate 61 and the right side wall 84 above the second edge line 65 (such as Figure 3 shown as ∠B in the figure) is an obtuse angle, and the included angle formed by the third valve plate 63 and the right side wall 84 below the second edge line 65 (such as Figure 3 shown as ∠C in the figure) is an acute angle. The horizontal distance between the first edge line 64 and the left side wall 83 is equal to 0.9 times the horizontal width of the material discharge channel 72.

[0034] The above embodiments are applied in an automatic feeding and discharging system for plastic particles, as shown in Figure 8As shown in the figure, the system is provided with a hopper 1, a two-way fan 30, and a horizontal conveying pipe 9. The material suction port of the hopper 1 is connected to the first end (the end located in the production area) of the horizontal conveying pipe 9 through the downstream section 42 of the material suction channel and a three-way valve 91. The material discharging port of the hopper 1 is connected to the first end of the horizontal conveying pipe 9 through the upstream section 71 of the material discharging channel and the three-way valve 91. The second end (the end located in the storage area) of the horizontal conveying pipe 9 is connected to the upper end of the vertical conveying pipe 8. The air duct of the two-way fan 30 extends into the hopper 1. The relevant flow channel structure between the two-way fan 30 and the upper end of the vertical conveying pipe 8 is the same as the structure disclosed in CN118769512B.

[0035] The above embodiments can automatically control the on-off state of the bifurcated flow channel during the material suction and discharging processes of the vertical conveying pipe, that is, automatically keep the material suction channel unblocked and the material discharging channel disconnected during material suction, and automatically keep the material discharging channel unblocked and the material suction channel disconnected during material discharging. Specifically as follows: I. Material suction process: 1. If at the starting state, the first edge line 64 of the hollow valve block 6 abuts against the left side wall 83 of the vertical conveying pipe 8 (as Figure 9 shown), then after the negative pressure generated by the two-way fan 30 is transmitted to the vertical conveying pipe 8, the one-way valve plate 5 is sucked up and rotates clockwise upward around its rotating shaft, and the material discharging channel 72 remains in the disconnected state (as Figure 10 shown). The material suction channel 41 remains unblocked. An upward channel for the plastic pellets to flow upward is formed between the third valve plate 63 of the hollow valve block and the right side wall 84. Therefore, the negative pressure can continuously suck up the plastic pellets through the material suction channel 41 and the upward channel between the third valve plate 63 and the right side wall 84, as Figure 11 shown. Then the plastic pellets are continuously sucked into the hopper 1 through the horizontal conveying pipe 9 and the downstream section 42 of the material suction channel; 2. If at the starting state, the second edge line 65 of the hollow valve block 6 abuts against the right side wall 84 of the vertical conveying pipe 8 (as Figure 12 shown), then after the negative pressure generated by the two-way fan 30 is transmitted to the vertical conveying pipe 8, the one-way valve plate 5 is first sucked up and rotates clockwise upward around its rotating shaft, and the material discharging channel 72 remains closed (as Figure 13 shown). Then the negative pressure is transmitted to the material suction channel 41 through the first air-permeable net 67 in the middle part of the second valve plate 62 and the second air-permeable net 68 in the middle part of the third valve plate 63. The plastic pellets in the material bucket 2 are sucked up and hit the third valve plate 63 of the hollow valve block, as Figure 14As shown, under the action of this impact force and the counterclockwise moment generated by the air pressure difference on the solid part of the third valve plate 63, the hollow valve block 6 rotates counterclockwise to the left around its rotating shaft 60 until the first ridge line 64 abuts against the left side wall 83 of the vertical feeding pipe 8. After that, the material suction channel 41 remains unblocked, and the material discharging channel 72 remains disconnected. The negative pressure can continuously suck up the plastic pellets through the material suction channel 41 and the rising channel between the third valve plate 63 and the right side wall 84 for continuous material suction, as Figure 15 shown.

[0036] II. Material discharging process: 1. If at the starting state, the second ridge line 65 of the hollow valve block 6 abuts against the right side wall 84 of the vertical feeding pipe 8 (as Figure 16 shown), then after the plastic pellet fluid blown by the hopper 1 reaches the upper end of the vertical feeding pipe 8, the plastic pellets flow downward and hit the first valve plate 61 of the hollow valve block. This impact force generates a weak horizontal component force to the right, and the hollow valve block 6 remains stationary. The material suction channel 41 remains disconnected, as Figure 16 shown, while the material discharging channel 72 remains unblocked. Thus, the plastic pellets can continuously fall into the lower bucket through the material discharging channel 72, as Figure 17 shown; 2. If at the starting state, the first ridge line 64 of the hollow valve block 6 abuts against the left side wall 83 of the vertical feeding pipe 8 (as Figure 18 shown), then after the plastic pellet fluid blown by the hopper 1 reaches the upper end of the vertical feeding pipe 8, the plastic pellets flow downward and hit the first valve plate 61 of the hollow valve block. The impact force of the falling plastic pellets and the gravity of the plastic pellets can generate a relatively large horizontal component force to the right on the first valve plate 61. Since the center of gravity point G of the hollow valve block 6 is originally close to the plane of the partition wall 85 and is close to the critical state of left - right balance, the hollow valve block 6 quickly rotates clockwise to the right, as Figure 19 shown. Then, under the continuous action of the gravity moment of the hollow valve block 6 itself and the impact force of the plastic pellets, the hollow valve block 6 quickly rotates to the extreme position to the right, making the second ridge line 65 abut against the right side wall 84 of the vertical feeding pipe 8, as Figure 20 shown. After that, the material suction channel 41 remains disconnected, and the material discharging channel 72 remains unblocked. Thus, the plastic pellets can continuously fall into the lower bucket through the material discharging channel 72.

[0037] As can be seen from the above, in the above process, the change of the on - off state of the bifurcated flow channels (i.e., the material suction channel 41 and the material discharging channel 72) does not require any manual intervention or the intervention of any electric mechanism.

[0038] In the above - mentioned embodiment, when the first ridge line 64 rotates to contact the left side wall, the acute angle formed by the first valve plate 61 and the left side wall 83 above the first ridge line 64 (as Figure 7The angle shown as ∠A can be changed to 40° or 58°. The horizontal distance between the second ridge line 65 and the right side wall 84 can be changed to be equal to 0.8 times or 1.0 times the horizontal width of the material suction channel 41.

[0039] In the above embodiments, when the second ridge line 65 rotates to contact the right side wall 84, the horizontal distance between the first ridge line 64 and the left side wall 83 can be changed to be equal to 0.8 times or 1.0 times the horizontal width of the material discharging channel 72.

Claims

1. A control structure for an automatic control of the on-off of a bifurcated flow channel in a vertical plastic pellet conveying pipe, comprising a vertical conveying pipe located above a material bucket. The lower section of the vertical conveying pipe bifurcates into two bifurcated flow channels, namely a material suction channel and a material discharging channel. The outlet at the bottom of the material suction channel is located in the lower part of the inner cavity of the material bucket, and the outlet at the bottom of the material discharging channel is located above the material bucket. It is characterized in that: The cross-section of the vertical material conveying pipe is rectangular. The vertical material conveying pipe is provided with a front side wall, a rear side wall, a left side wall, and a right side wall. A partition wall is provided in the center of the inner cavity of the vertical material conveying pipe. The partition wall is parallel to the left side wall and the right side wall. The bottom edges of the left half of the front side wall, the left half of the rear side wall, and the left side wall are higher than the bottom edge of the partition wall. The bottom edges of the right half of the front side wall, the right half of the rear side wall, and the right side wall are flush with the bottom edge of the partition wall. The space enclosed by the right half of the front side wall, the right half of the rear side wall, the right side wall, and the partition wall forms the material suction channel. The space enclosed by the left half of the front side wall, the left half of the rear side wall, the left side wall, and the partition wall forms the material discharging channel; a one-way valve plate is provided in the material discharging channel, and the opening direction of the one-way valve plate is to rotate downward; a hollow valve block is rotatably installed in the vertical material conveying pipe, the extending direction of the rotating shaft of the hollow valve block is longitudinal, and the central axis of the rotating shaft of the hollow valve block is located at the top edge of the partition wall; the longitudinal length of the hollow valve block is equivalent to the longitudinal dimension of the pipe cavity of the vertical material conveying pipe; the hollow valve block includes three valve plates that are connected together to form a triangular prism shape. The three valve plates are respectively called the first valve plate, the second valve plate, and the third valve plate. The intersection line of the first valve plate and the second valve plate is called the first edge line, the intersection line of the first valve plate and the third valve plate is called the second edge line, and the intersection line of the second valve plate and the third valve plate is called the third edge line. The third edge line is close to and parallel to the rotating shaft of the hollow valve block; the third edge line is located at the lowest point of the entire hollow valve block, and the first edge line is more to the left than the second edge line; ventilation nets are respectively provided at the middle parts of the second valve plate and the third valve plate; When the first edge line rotates to contact the left side wall, the first valve plate and the left side wall above the first edge line form an acute angle less than 60°, and the center of gravity of the entire hollow valve block is located on the left side of the plane where the partition wall is located and close to the plane where the partition wall is located; When the second edge line rotates to contact the right side wall, the center of gravity of the entire hollow valve block is located on the right side of the plane where the partition wall is located. The first valve plate and the right side wall above the second edge line form an obtuse angle, and the third valve plate and the right side wall below the second edge line form an acute angle.

2. The plastic pellet vertical feeding pipe control structure for automatically controlling the on / off of the bifurcated flow channel according to claim 1, characterized in that: A counterweight is provided at the upper right corner of the hollow valve block.

3. The plastic pellet vertical feeding pipe control structure for automatically controlling the on / off of the bifurcated flow path according to claim 1, wherein: When the first edge line rotates to contact the left side wall, the horizontal distance between the second edge line and the right side wall is equal to 0.8 - 1.0 times the horizontal width of the material suction channel.

4. The plastic pellet vertical feeding pipe control structure for automatically controlling the on-off of the bifurcated flow channel according to claim 1, wherein: When the second edge line rotates to contact the right side wall, the horizontal distance between the first edge line and the left side wall is equal to 0.8 - 1.0 times the horizontal width of the material discharging channel.

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