Continuous single-screw extruder based on liquid metering and batching system

Abstract

The invention relates to the technical field of extruders, in particular to a continuous single-screw extruder based on a liquid metering batching system.The continuous single-screw extruder comprises a plurality of material collecting bins, a material mixing bin and a liquid metering device, the material collecting bins are used for storing materials, and a stirring mechanism used for mixing the materials is arranged in the material mixing bin; the material collecting bins and the material mixing bin are arranged from top to bottom and sequentially communicated, a first discharging valve is correspondingly arranged at the communication position of the lower end of each material collecting bin and the upper end of the material mixing bin, a weighing hopper is arranged in the material mixing bin, the output end of each first discharging valve is communicated with the weighing hopper, a spraying head is arranged in the material mixing bin, and the spraying head is connected with the spraying head. When the mixing device is used, the output end of the liquid metering device is communicated with the inside of the mixing bin, liquid and materials are directly mixed, granulation is not needed to form master batches, production procedures are reduced, materials can be continuously mixed, production efficiency is improved, and production cost is reduced.

Description

Technical Field

[0001] The invention relates to the technical field of extruders, in particular to a continuous single-screw extruder based on a liquid metering and batching system. Background Art

[0002] Single screw extruder is a commonly used plastic processing machinery, which mainly includes batching system, extrusion system and transmission system, wherein a relatively closed structure is formed between the batching system and the extrusion system. The closed structure helps to ensure a certain pressure and temperature during the material melting and extrusion process, and improves the stability of extrusion and the quality of the discharge. In addition, the closed structure also helps to reduce the oxidation and degradation of the material during the extrusion process, and improves the discharge performance. Therefore, the closed single screw extruder has a wide range of application prospects in the plastic processing industry. Its high efficiency, stability, wide applicability and easy maintenance make it the preferred equipment for many plastic processing companies. If there is a liquid ingredient in the extruded product, a twin screw extruder is usually used, because the twin screw extruder is open and easy to add liquid, but the extrusion effect of the twin screw extruder is not as good as that of the single screw extruder.

[0003] If there are liquid ingredients in the extruded product, in order to use it with a single-screw extruder, it is generally necessary to first mix the material and the liquid, granulate them through a twin-screw extruder to form a masterbatch, and then extrude it through a single-screw extruder. The increase in processes leads to a longer production cycle and a greatly increased manufacturing cost. At the same time, for sensitive additives, they are heated twice during the processing process, which has a great impact on the performance. Summary of the invention

[0004] The technical problem to be solved by the present invention is: in order to solve the problem that extruded products containing liquid ingredients in the prior art cannot be directly extruded continuously by a single screw through the existing ingredient system, a continuous single screw extruder based on a liquid metering ingredient system is provided.

[0005] The technical solution adopted by the present invention to solve its technical problems is: a continuous single-screw extruder based on a liquid metering and dosing system, comprising a plurality of collecting bins, mixing bins and a liquid metering device, wherein the collecting bins are used to store materials, and a stirring mechanism for mixing materials is arranged in the mixing bins, the collecting bins and the mixing bins are arranged from top to bottom and connected in sequence, and a first discharge valve is correspondingly arranged at the connection point between the lower end of each collecting bin and the upper end of the mixing bin, a weighing hopper is arranged in the mixing bin, and the output end of each first discharge valve is connected to the weighing hopper, a spray head is arranged in the mixing bin, and the spray head is connected to the output end of the liquid metering device, and the spray heads are all located above the stirring mechanism, and the mixing bin is connected to the single-screw extruder. Compared with the prior art, this solution connects the output end of the liquid metering device with the spray head, and the spray head is located in the mixing bin. The spray head is located on the stirring mechanism, so that the liquid and the material are directly mixed without the need for granulation to form masterbatch, thereby reducing the production process and allowing continuous and uninterrupted mixing, thereby improving production efficiency and reducing production costs.

[0006] In order to facilitate continuous and uninterrupted production, some preferred embodiments further include a storage bin for storing the mixed materials, the storage bin is arranged below the mixing bin and is interconnected, and the discharge port of the storage bin is connected to the feed port of the single screw extruder. By storing the mixed materials in the storage bin, the single screw extruder does not need to wait for the materials in the mixing bin to be mixed before extruding, thereby improving work efficiency.

[0007] In order to better proportion the materials, in some preferred embodiments, the output end of the weighing hopper is provided with a second discharge valve, and the weighing hopper is provided with a cylinder for controlling the second discharge valve to control the discharge or cut-off of the output end of the weighing hopper. The second discharge valve is controlled by the cylinder, and the materials in the collection bin are added to the weighing hopper in turn according to the weight proportion, and then concentrated into the mixing bin, so as to better proportion the required materials.

[0008] In order to realize the stirring mechanism, some preferred embodiments include a spiral stirring shaft, the spiral stirring shaft is arranged in the mixing bin, and a driving mechanism for driving the spiral stirring shaft to rotate is arranged on the mixing bin. The spiral stirring shaft is driven by the driving mechanism to stir the material.

[0009] In order to ensure stable and reliable mixing, some preferred embodiments are: a material through hole is provided between the lower end of the mixing bin and the upper end of the storage bin; the second discharge valve is inclined gradually from top to bottom toward the input end of the spiral stirring shaft during discharge; the output end of the liquid metering device is located at the input end of the spiral stirring shaft; and the material through hole is located at the output end of the spiral stirring shaft.

[0010] In order to facilitate the control of mixing time and ensure that the materials are fully mixed, in some preferred embodiments, the storage bin is provided with a third discharge valve at the material passage hole.

[0011] In order to achieve continuous and uninterrupted mixing, in some preferred embodiments, a material level sensor for detecting the material position is provided in the mixing bin. By providing a material level sensor on the mixing bin, the material situation in the mixing bin is monitored in real time, and when the material in the mixing bin decreases, the material is replenished in time for mixing, thereby achieving continuous and uninterrupted mixing.

[0012] In some preferred embodiments, the spray head is located between the stirring mechanism and the weighing hopper.

[0013] In order to facilitate the loading of the aggregate bin, some embodiments preferably further include a vacuum loader for loading the aggregate bin, and the vacuum loader is arranged one by one with the aggregate bin. By arranging a vacuum loader on each aggregate bin, the vacuum loader can replenish the material in the aggregate bin in time, so as to achieve continuous and uninterrupted loading.

[0014] In order to facilitate observation of the material conditions in the aggregate bin, preferably in some embodiments, each of the aggregate bins is provided with an observation window for observing the interior thereof. By providing the observation window on the aggregate bin, it is convenient to observe the material conditions in the aggregate bin.

[0015] The beneficial effects of the present invention are as follows: when the continuous single-screw extruder based on the liquid metering and batching system of the present invention is in use, the output end of the liquid metering device is connected to the spray head, the spray head is located in the mixing bin, and the spray head is located on the stirring mechanism, so that the liquid and the material are directly mixed, and there is no need to granulate to form master batches, thereby reducing the production process, and can continuously and uninterruptedly mix materials, thereby improving production efficiency and reducing production costs. The closed single-screw extruder ensures the material extrusion effect and avoids the problem that when there is liquid ingredient in the extruded product, it is generally necessary to mix the material and the liquid first, granulate through a twin-screw to form a master batch, and then extrude through a single-screw extruder in order to cooperate with the single-screw extruder. The number of processes increases, resulting in a longer production cycle, and the manufacturing cost will also be greatly increased. At the same time, for sensitive additive materials, they are heated twice during the processing process, which has a great impact on the performance. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The present invention is further described below in conjunction with the accompanying drawings and embodiments.

[0017] Figure 1 It is a schematic diagram of the structure of the present invention;

[0018] Figure 2 It is a schematic diagram of the installation structure of the material collection bin and the vacuum feeder in the present invention;

[0019] Figure 3 yes Figure 2 Middle AA section view;

[0020] Figure 4 It is a schematic diagram of the structure between the mixing bin, the stirring mechanism and the storage bin in the present invention;

[0021] Figure 5 It is a spectrum diagram of quantum dots of the plate made in the present invention.

[0022] In the figure: 1. collecting bin, 2. mixing bin, 3. liquid metering device, 4. stirring mechanism, 5. first discharge valve, 6. single screw extruder, 7. storage bin, 8. weighing hopper, 9. second discharge valve, 10. spiral stirring shaft, 11. driving mechanism, 12. material hole, 13. third discharge valve, 14. material level sensor, 15. spray head, 16. vacuum feeder, 17. observation window, 18. cylinder. DETAILED DESCRIPTION

[0023] The present invention is further described in detail below in conjunction with embodiments:

[0024] The present invention is not limited to the following specific embodiments. A person skilled in the art can implement the present invention in various other specific embodiments according to the contents disclosed in the present invention, or any simple changes or modifications made to the design structure and ideas of the present invention fall within the protection scope of the present invention. It should be noted that the embodiments and features in the embodiments of the present invention can be combined with each other without conflict.

[0025] Example 1

[0026] like Figure 1-5As shown, a continuous single-screw extruder based on a liquid metering and batching system includes four collecting bins 1, a mixing bin 2, a storage bin 7, two liquid metering devices 3 and four vacuum feeders 16. The four collecting bins 1 are used to store materials that need to be mixed. The mixing bin 2 is provided with a stirring mechanism 4. The storage bin 7 is used to store the mixed materials. The liquid metering device 3 is used to transport the liquid to the mixing bin 2 according to the required metering. The vacuum feeder 16 is used to feed the collecting bin 1. The collecting bin 1, the mixing bin 2 and the storage bin 7 are arranged from top to bottom and are connected in sequence. A first discharge valve 5 is correspondingly provided at the connection between the lower end of each collecting bin 1 and the upper end of the mixing bin 2. The discharge port of the storage bin 7 is connected to the single The feed port of the screw extruder 6 is connected, a weighing hopper 8 is arranged in the mixing bin 2, the output end of each first discharge valve 5 is connected with the weighing hopper 8, a spray head 15 is arranged in the mixing bin 2, the spray head 15 is connected with the output ends of the two liquid metering devices 3, the spray heads 15 are all located above the stirring mechanism 4, the output end of the vacuum feeder 16 is connected with the collecting bin 1 one by one, and each collecting bin 1 is provided with an observation window 17 for observing the interior thereof, and at the same time, a closed structure is formed between the four collecting bins 1, the mixing bin 2, the storage bin 7, the liquid metering device 3 and the single screw extruder 6, which helps to reduce the oxidation and degradation of the material during the extrusion process and improves the discharge performance.

[0027] The output end of the weighing hopper 8 is provided with a second discharge valve 9, and the weighing hopper 8 is provided with a cylinder 18 for controlling the second discharge valve 9 to control the discharge or cut-off of the output end of the weighing hopper 8. The stirring mechanism 4 includes a spiral stirring shaft 10, and the spiral stirring shaft 10 is arranged in the mixing bin 2 through a bearing for horizontal rotation. The mixing bin 2 is provided with a driving mechanism 11, and the driving mechanism 11 is used to drive the spiral stirring shaft 10 to rotate. In this embodiment, the driving mechanism 11 is a motor, and the motor is connected to the spiral stirring shaft 10 through a coupling. A mutually connected coupling is provided between the lower end of the mixing bin 2 and the upper end of the storage bin 7. The material through hole 12 is used to realize the connection between the mixing bin 2 and the storage bin 7. The second discharge valve 9 is inclined from top to bottom gradually toward the input end of the spiral stirring shaft 10 during discharge. The output end of the liquid metering device 3 is located at the input end of the spiral stirring shaft 10, and the material through hole 12 is located at the output end of the spiral stirring shaft 10. A material level sensor 14 for detecting the material position is provided in the mixing bin 2. The material level sensor 14 is located between the spiral stirring shaft 10 and the spray head 15. In this embodiment, the second discharge valve 9 is staggered with the material through hole 12. Therefore, the third discharge valve 13 may not be provided at the material through hole 12.

[0028] When the above-mentioned continuous single-screw extruder based on the liquid metering and batching system is in use, the mixed material is first fed through the corresponding vacuum feeder 16, and the material enters the corresponding collecting bin 1, and then the first discharge valve 5 of the corresponding collecting bin 1 is controlled to discharge the materials of each required weight into the weighing hopper 8 in turn, and then the second discharge valve 9 is controlled by the cylinder 18 to transport the material to the mixing bin 2. When the cylinder 18 controls the second discharge valve 9 to open the valve to discharge the material, the two liquid metering devices 3 both spray the liquid onto the material through the spray head 15, and then the stirring mechanism 4 mixes the material. Of course, the liquid metering device 3 can also be used to transport the liquid during each material proportioning process, and the stirring mechanism 4 is started to mix and stir the material. After the stirring is completed, the material is transported to the storage bin 7 below, and the material can directly enter the single-screw extruder 6 for extrusion;

[0029] This embodiment is mainly used for materials that need to add liquid processing aids, specifically the addition of red and green quantum dot liquids, liquid flame retardants, antistatic agents, chain extenders, reactive coupling agents, color oils, etc. The products produced are such as quantum dot plates, sheets, flame retardant sheets, antistatic sheets and films, and some functional single-screw extrusion products, etc., wherein the quantum dots are quantum dot particles, n-hexane, ethanol, etc., and the liquid flame retardants are silicone flame retardants, siloxane copolymers, etc. The liquid addition ratio is 0.05% to 3%, and the addition ratio is related to the content of the active ingredients in the liquid raw materials. For example, the preparation process of the quantum dot diffusion plate:

[0030] The first step is to place the green quantum dot solution (350 mg / ml) and the red quantum dot solution (250 mg / ml) in the containers of the two liquid metering devices 3 respectively, and mix them at the spray head 15 in the proportion of 100 ml of green quantum dot solution and 10 ml of red quantum dot solution during the filling process;

[0031] Step 2: Liquid is automatically added to the ingredients through the spray head 15 according to the set weight and mixed. The plates are mixed according to the formula in Table 1 below, using a liquid batching system;

[0032] Table 1

[0033]

[0034] Step 3: Extruding the sheet through a single screw extruder, the sheet achieves the quantum dot test results shown in Table 2;

[0035] Table 2

[0036] Light transmittance Haze 65.39％ 94.20

[0037] The fourth step is to satisfy the quantum dot spectrum, where the horizontal axis is the wavelength in nm and the vertical axis is the relative spectral intensity.

[0038] Example 2

[0039] The difference between Example 2 and Example 1 is that the storage bin 7 is provided with a third discharge valve 13 at the material through hole 12. The third discharge valve 13 is for the purpose of controlling the mixing time of the materials, better mixing the materials, and also for the purpose of providing the mixing bin 2 with continuous and uninterrupted supply. In this embodiment, the material through hole 12 and the second discharge valve 9 can be staggered, or the material through hole 12 and the second discharge valve 9 can be arranged without staggering.

[0040] The above-mentioned ideal embodiments of the present invention are for inspiration. Through the above-mentioned description, relevant staff can make various changes and modifications without departing from the technical idea of ​​the present invention. The technical scope of the present invention is not limited to the contents of the specification, and its technical scope must be determined according to the scope of the claims.

Claims

1. A continuous single screw extruder based on a liquid metering and batching system, characterized in that: The invention comprises a plurality of material collecting bins (1), a mixing bin (2) and a liquid metering device (3), wherein the material collecting bin (1) is used to store materials, and the mixing bin (2) is provided with a stirring mechanism (4) for mixing materials. The material collecting bin (1) and the mixing bin (2) are arranged from top to bottom and are connected in sequence. A first discharge valve (5) is correspondingly provided at the connection point between the lower end of each material collecting bin (1) and the upper end of the mixing bin (2). A weighing hopper (8) is provided in the mixing bin (2), and the output end of each first discharge valve (5) is connected to the weighing hopper (8). A spray head (15) is provided in the mixing bin (2), and the spray head (15) is connected to the output end of the liquid metering device (3). The spray head (15) is located above the stirring mechanism (4), and the mixing bin (2) is connected to a single-screw extruder (6).

2. A continuous single screw extruder based on a liquid metering and batching system according to claim 1, characterized in that: It also includes a storage bin (7) for storing mixed materials. The storage bin (7) is arranged below the mixing bin (2) and is interconnected. The discharge port of the storage bin (7) is connected to the feed port of the single-screw extruder (6).

3. A continuous single screw extruder based on a liquid metering and batching system according to claim 2, characterized in that: The output end of the weighing hopper (8) is provided with a second discharge valve (9), and the weighing hopper (8) is provided with a cylinder (18) for controlling the second discharge valve (9) to control the discharge or cut-off of the output end of the weighing hopper (8).

4. A continuous single screw extruder based on a liquid metering and batching system according to claim 3, characterized in that: The stirring mechanism (4) comprises a spiral stirring shaft (10), wherein the spiral stirring shaft (10) is arranged in a mixing bin (2), and a driving mechanism (11) for driving the spiral stirring shaft (10) to rotate is arranged on the mixing bin (2).

5. A continuous single screw extruder based on a liquid metering and batching system according to claim 4, characterized in that: A material passage hole (12) is provided between the lower end of the mixing bin (2) and the upper end of the storage bin (7); the second discharge valve (9) is arranged to be inclined gradually from top to bottom toward the input end of the spiral stirring shaft (10) during material discharge; the output end of the liquid metering device (3) is located at the input end of the spiral stirring shaft (10); and the material passage hole (12) is located at the output end of the spiral stirring shaft (10).

6. A continuous single screw extruder based on a liquid metering and batching system according to claim 4 or 5, characterized in that: The storage bin (7) is provided with a third discharge valve (13) at the material passage hole (12).

7. A continuous single screw extruder based on a liquid metering and batching system according to claim 1, characterized in that: A material level sensor (14) for detecting the position of materials is arranged in the mixing bin (2).

8. The continuous single screw extruder based on a liquid metering and batching system according to claim 1, characterized in that: The spray head (15) is located between the stirring mechanism (4) and the weighing hopper (8).

9. A continuous single screw extruder based on a liquid metering and batching system according to claim 1, characterized in that: It also comprises a vacuum loader (16) for loading materials into the material collection bin (1), wherein the vacuum loader (16) is arranged in a one-to-one correspondence with the material collection bin (1).

10. The continuous single screw extruder based on a liquid metering and batching system according to claim 1, characterized in that: Each of the aggregate bins (1) is provided with an observation window (17) for observing the interior thereof.

Images