Auxiliary agent injection device of screw extruder

Abstract

The auxiliary agent injection device comprises a shell, a lifting rod and a driving assembly, the shell is used for being connected with the screw extruder, the shell is provided with an inner channel communicated with an auxiliary agent source, and an opening is formed in the lower end of the shell; the lifting rod is movably arranged in the shell, the shell and the lifting rod are both vertically arranged, and a blocking part is arranged at the lower end of the lifting rod; the driving assembly is used for driving the lifting rod to move in the height direction of the shell. The lifting rod has a first position and a second position, when in the first position, the blocking part extends out of the opening in the lower end of the shell, and the inner channel can be communicated with the screw extruder; at the second position, the blocking part is positioned in the shell, so that the lower end opening of the shell is closed. The auxiliary agent injection device of the screw extruder provided by the utility model can be used for adjusting the flowing-out flow of an auxiliary agent and solving the problem of nozzle blockage caused by intermittent injection; the device is simple in structure and convenient to mount; energy consumption and extra maintenance cost are avoided; the use effect is good and cleaning is convenient.

Description

Technical Field

[0001] This utility model relates to an additive injection device for a screw extruder. Background Technology

[0002] Existing continuous production lines for recycled bottle flake fibers utilize twin-screw extruders. These extruders use recycled plastic from waste cola bottles as raw material, melting the recycled plastic flakes and extrude them to produce recycled fibers. A screw extruder is a thermoplastic molding machine, a primary piece of equipment for extruding plastic products, and is widely used in various industries such as recycled plastic fibers, plastic pipes, cables, building structural products, household appliances, stationery, packaging, and automotive parts. The screw extruder utilizes the helical pushing motion of the screws to guide various materials from the feed zone into the heating zone for melting. Through the changes in the pitch and direction of the twin screws, the plastic and thermoplastic materials are mixed, shaped, and extruded within the extruder, resulting in the molding of plastic products.

[0003] To improve the quality and meet product demands, it is common practice to inject necessary additives into the plastic melting section of the extruder. Currently, an opening is created in the plastic melting section of the extruder, into which a needle-type injection nozzle (with a hollow channel) is inserted. The required amount of additive is injected when needed, and delivery is stopped once the required amount has been injected. The problem is that the needle-type injection nozzle remains constantly connected to the plastic melting section of the extruder. Because the required additive dosage is small and the nozzle's outlet diameter is small, when no additive delivery is needed, molten plastic material from the plastic melting section enters the needle-type injection nozzle, frequently causing blockage. When additive delivery is needed again, it becomes impossible to inject it into the plastic melting section through the nozzle. Increasing the injection volume affects the product, and since the nozzle outlet diameter is uniform, the amount of additive injected cannot be adjusted. Utility Model Content

[0004] The purpose of this invention is to provide an additive injection device for a screw extruder, which solves the problem of nozzle clogging caused by intermittent additive injection.

[0005] To achieve the above objectives, the technical solution adopted by this utility model is as follows:

[0006] An additive injection device for a screw extruder includes a housing, a lifting rod, and a drive assembly. The housing is used to connect to the screw extruder and has an internal channel communicating with an additive source. An opening is provided at the lower end of the housing. The lifting rod is movably disposed within the housing. Both the housing and the lifting rod are vertically arranged, and a blocking part is provided at the lower end of the lifting rod. The drive assembly is used to drive the lifting rod to move along the height direction of the housing.

[0007] The lifting rod has a first position and a second position. When it is in the first position, the blocking part extends out of the opening at the lower end of the housing, and the inner channel can communicate with the screw extruder. When it is in the second position, the blocking part is located inside the housing, so that the opening at the lower end of the housing is closed.

[0008] According to some embodiments of this utility model, the drive assembly includes an adjusting bolt, a nut, an elastic element, and a first washer. The adjusting bolt is threadedly connected to the upper end of the housing. The adjusting bolt can move along the height direction of the housing until it abuts against the lifting rod to push the lifting rod downward. The nut, the elastic element, and the first washer are all sleeved on the lifting rod. The nut is located above the first washer. The first washer is fixedly disposed inside the housing. One end of the elastic element abuts against the nut, and the other end of the elastic element abuts against the first washer.

[0009] According to some embodiments of the present invention, the device further includes a second washer, which is sleeved outside the lifting rod and located under the nut, with one end of the elastic member abutting against the second washer.

[0010] According to some embodiments of this utility model, the diameter of the blocking part gradually increases from top to bottom, or the diameter of the blocking part gradually decreases from top to bottom.

[0011] According to some embodiments of the present invention, the lower end of the shell includes a first section, a second section and a third section connected in sequence, the diameter of the second section is smaller than the diameter of the first section, the diameter of the third section is smaller than the diameter of the second section, and a third gasket is provided between the screw extruder and the outer periphery of the second section.

[0012] According to some embodiments of the present invention, the housing includes an upper housing and a lower housing, which are detachably connected.

[0013] According to some embodiments of this utility model, the diameter of the upper shell is larger than the diameter of the lower shell.

[0014] According to some embodiments of this utility model, one of the lower end of the upper shell and the upper end of the lower shell is provided with an insertion part, and the other is provided with a recessed part for insertion of the insertion part.

[0015] According to some embodiments of the present invention, the housing is provided with an auxiliary agent injection port that communicates with the inner channel, and the auxiliary agent injection port is located on the side of the housing.

[0016] According to some embodiments of this utility model, the outer surface of the housing is provided with an external thread that is threadedly connected to the screw extruder.

[0017] Due to the application of the above technical solution, this utility model has the following advantages compared with the prior art:

[0018] The screw extruder additive injection device provided by this utility model can adjust the flow rate of the additive by adjusting the distance the lifting rod moves along the height direction through the drive assembly. When the lifting rod is in the second position, the blocking part is located inside the housing, closing the lower opening of the inner channel and preventing material from entering the housing and clogging it, thus solving the nozzle clogging problem caused by intermittent injection. The device has a simple structure and is easy to install; it consumes no energy and requires no additional maintenance costs; it has good performance, is easy to clean, and simple to maintain. Attached Figure Description

[0019] Appendix Figure 1 A structural diagram of the screw extruder additive injection device provided by this utility model in the liquid injection state;

[0020] Appendix Figure 2 For the appendix Figure 1 Enlarged view of the driving component;

[0021] Appendix Figure 3 A structural diagram of the screw extruder additive injection device provided by this utility model in a non-liquid injection state;

[0022] Appendix Figure 4 Exploded view of the adjusting bolt, upper housing, and lower housing of the screw extruder auxiliary injection device provided by this utility model;

[0023] Appendix Figure 5 Exploded view of the adjusting bolt and lifting rod of the screw extruder auxiliary injection device provided by this utility model;

[0024] Appendix Figure 6 A top view of the second gasket of the screw extruder additive injection device provided by this utility model;

[0025] Appendix Figure 7 A side view of the housing of the screw extruder additive injection device provided by this utility model;

[0026] Appendix Figure 8 For the appendix Figure 7 Structural diagram of direction A in the middle;

[0027] Appendix Figure 9 A structural diagram showing the connection between the screw extruder additive injection device provided by this utility model and the screw extruder;

[0028] Appendix Figure 10 For the appendix Figure 9 Enlarged view of the additive injection device for a medium screw extruder.

[0029] In the attached diagrams above:

[0030] 1-Shell, 11-Upper shell, 111-Auxiliary injection port, 112-Insertion part, 113-Groogging, 12-Lower shell, 121-First section, 1211-External thread, 122-Second section, 123-Third section, 124-Recessed part; 2-Adjusting bolt; 3-Nut; 4-Elastic element; 5-First gasket; 6-Second gasket; 7-Lifting rod; 8-Blocking part; 9-Screw extruder. Detailed Implementation

[0031] The technical solution of this utility model will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this utility model. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this utility model.

[0032] In the description of this utility model, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the accompanying drawings and are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0033] See Figures 1 to 10 The screw extruder additive injection device shown includes a housing 1, a lifting rod 7, and a drive assembly. The housing 1 is used to communicate with the screw extruder 9 and has an internal channel communicating with the additive source. An opening is provided at the lower end of the housing 1. The lifting rod 7 is movably disposed inside the housing 1. Both the housing 1 and the lifting rod 7 are vertically arranged (along the Z-axis). A blocking part 8 is provided at the lower end of the lifting rod 7. The drive assembly is used to drive the lifting rod 7 to move along the height direction of the housing 1.

[0034] The lifting rod 7 has a first position and a second position. When in the first position, the blocking part 8 extends out of the opening at the lower end of the housing 1, and the inner channel can communicate with the screw extruder 9, allowing liquid injection; that is, the device is in the liquid injection state. When in the second position, the blocking part 8 is located inside the housing 1, closing the lower opening of the inner channel; that is, liquid injection is not performed; that is, the device is in the non-liquid injection state. By driving the lifting rod 7 to move a certain distance in the height direction through the drive assembly, the gap (opening) between the blocking part 8 and the inner channel of the housing 1 can be adjusted, which in turn adjusts the flow rate of the excipient.

[0035] In some embodiments, the drive assembly includes an adjusting bolt 2, a nut 3, an elastic element 4, and a first washer 5. The adjusting bolt 2 is threadedly connected to the upper opening of the housing 1 (the upper opening of the housing 1 has an internal thread that mates with the adjusting bolt 2). The adjusting bolt 2 can move along the height direction of the housing until it abuts against the lifting rod 7 to push the lifting rod 7 downward. The nut 3, the elastic element 4, and the first washer 5 are all sleeved on the outside of the lifting rod 7. The nut 3 is located above the first washer 5, and the first washer 5 is fixedly installed inside the housing, i.e., the position of the first washer 5 is fixed. The elastic element 4 is a spring, with one end abutting against the nut 3 and the other end abutting against the first washer 5. When the lifting rod 7 moves along the height direction of the housing 1, the nut 3 moves accordingly.

[0036] The specific implementation method for the lifting rod 7 to move along the height direction of the housing 1 is as follows: The adjusting bolt 2 enters from the upper opening of the housing 1 and moves downward along the height direction of the housing 1 until it abuts against the lifting rod 7 to push the lifting rod 7 downward. During the downward movement of the lifting rod 7, the elastic element 4 is compressed, and the blocking part 8 extends out of the lower opening of the housing 1. Then, after the auxiliary agent is injected, the auxiliary agent is injected. After a certain amount of auxiliary agent is injected, the adjusting bolt 2 is rotated in the opposite direction to move the adjusting bolt 2 upward. Under the action of the elastic force of the elastic element 4, the lifting rod 7 moves upward, and the blocking part 8 is retracted into the housing 1. The lower end face of the blocking part 8 is flush with the lower end face of the housing 1, so that the lower opening of the channel inside the housing 1 is closed, the auxiliary agent cannot flow out, and the material in the screw extruder 9 will not flow into the channel inside the housing.

[0037] In this example, the adjusting bolt 2 has a fine thread structure, which facilitates fine adjustment of the moving distance of the lifting rod 7 and the extension degree of the blocking part 8, thereby improving control accuracy.

[0038] In some embodiments, the device further includes a second washer 6, which is sleeved on the outside of the lifting rod 7 and located below the nut 3. One end of the elastic member 4 abuts against the second washer 6. The second washer 6 is preferably a metal washer, and the abutment between the elastic member 4 and the second washer 6 facilitates the stable setting of the elastic member 4.

[0039] In this example, a limiting part is provided at the upper end of the housing 1. The limiting part can be a slot 113. The upper part of the slot 113 is open, and the open side is located at the upper end of the housing 1, that is, an opening is provided at the upper end of the housing 1. The slot 113 has a bottom wall. When the device is in the liquid injection state, the second gasket 6 abuts against the bottom of the slot 113. The limiting part is provided to restrict the lifting rod 7 from moving a distance along the height direction of the housing 1.

[0040] In some embodiments, both the blocking part 8 and the lifting rod 7 are solid structures. The lower end face of the blocking part 8 is a horizontal plane, and the lower end face of the housing 1 is a horizontal plane. When the device is in a non-liquid injection state, the lower end face of the blocking part 8 is flush with the lower end face of the housing 1, so that the lower end opening of the inner channel is closed, and the auxiliary liquid cannot enter the screw extruder 9 from the lower end opening of the inner channel.

[0041] Preferably, the blocking part 8 is conical, such as the diameter of the blocking part 8 gradually increasing from top to bottom, or the diameter of the blocking part 8 gradually decreasing from top to bottom. Correspondingly, the lower opening of the housing 1 is conical to match the blocking part 8. The advantage of this arrangement is that the blocking part 8 has a larger sealing cross section and a better sealing effect, which can prevent material blockage.

[0042] In some embodiments, the lower end of the housing 1 includes a first segment 121, a second segment 122, and a third segment 123 connected in sequence. The diameter of the second segment 122 is smaller than the diameter of the first segment 121, and the diameter of the third segment 123 is smaller than the diameter of the second segment 122. A third gasket is provided between the screw extruder 9 and the outer periphery of the second segment 122. The third gasket is preferably a metal gasket. After the third gasket is installed, the leakage of material from the cavity of the screw extruder 9 is blocked, and the sealing effect between the housing 1 and the screw extruder 9 is better.

[0043] In some embodiments, the housing 1 includes an upper housing 11 and a lower housing 12, which are detachably connected for easy installation and storage.

[0044] See Figure 3 An insertion part 112 is provided on one of the lower ends of the upper housing 11 and the upper ends of the lower housing 12, and a recessed part 124 is provided on the other for the insertion part 112 to be inserted. Preferably, the insertion part 112 and the recessed part 124 are threadedly connected to facilitate the connection or disassembly of the upper housing 11 and the lower housing 12.

[0045] In some embodiments, the upper housing 11 needs to be slotted to accommodate the adjusting bolt 2, and the diameter of the upper housing 11 is larger than the diameter of the lower housing 12.

[0046] In some embodiments, the housing is provided with an excipient injection port 111 that communicates with the inner channel. The excipient injection port 111 is located on the side of the housing. One end of the excipient medium pipeline extends into the excipient injection port 111 and communicates with the inner channel, while the other end of the excipient medium pipeline is communicated with the excipient source.

[0047] In this example, the housing 1 is threadedly connected to the screw extruder 9. Specifically, the outer periphery of the first section 121 at the lower end of the housing 1 is provided with an external thread 1211 that is helically engaged with the screw extruder 9.

[0048] The specific implementation method for using the auxiliary agent injection device of the screw extruder 9 in this example to deliver auxiliary agent to the plastic melting section of the screw extruder 9 is as follows: The housing 1 is installed in the plastic melting section of the screw extruder 9. The external auxiliary agent injection medium line is installed in the internal thread of the auxiliary injection port through a threaded connection. The adjusting bolt 2 is slowly rotated to lower the lifting rod 7. The elastic element 4 is pressed down by force, so that the blocking part 8 extends out of the lower end opening of the housing. Then, the auxiliary agent is injected into the auxiliary agent medium line. The auxiliary agent is sprayed into the plastic melting section cavity of the screw extruder 9 through the lower end opening of the housing 1 along the inner pipe of the housing 1, thus completing the auxiliary agent injection. After the auxiliary agent injection is completed, the adjusting bolt 2 is rotated counterclockwise. Under the elastic force of the elastic element 4, the lifting rod 7 is pushed up, and the blocking part 8 is retracted to the initial state (reset) inside the housing 1. The lower end face of the blocking part 8 is flush with the lower end face of the housing, so that the lower end opening of the inner channel of the housing 1 is closed, preventing the backflow of material in the cavity of the screw extruder 9 from blocking the housing 1.

[0049] The advantage of the additive injection device for the screw extruder 9 in this example is that the distance by which the lifting rod 7 moves along the height direction can be adjusted by driving the lifting rod 7 through the drive assembly, thereby adjusting the gap (opening) between the blocking part 8 and the inner channel of the housing 1 to regulate the flow rate of the additive. When the lifting rod 7 is in the second position, the blocking part 8 is located inside the housing, so that the lower end opening of the inner channel is closed, and the material inside the screw extruder 9 will not enter the housing and will not block the housing.

[0050] The above embodiments are only for illustrating the technical concept and features of this utility model, and are intended to enable those skilled in the art to understand the content of this utility model and implement it accordingly. They should not be construed as limiting the scope of protection of this utility model. All equivalent changes or modifications made in accordance with the spirit and essence of this utility model should be included within the scope of protection of this utility model.

Claims

1. An additive injection device for a screw extruder, characterized in that, The device includes a housing, a lifting rod, and a drive assembly. The housing is used to connect to a screw extruder and has an internal channel communicating with an excipient source. An opening is provided at the lower end of the housing. The lifting rod is movably disposed within the housing. Both the housing and the lifting rod are vertically arranged, and a blocking part is provided at the lower end of the lifting rod. The drive assembly is used to drive the lifting rod to move along the height direction of the housing. The lifting rod has a first position and a second position. When it is in the first position, the blocking part extends out of the opening at the lower end of the housing, and the inner channel can communicate with the screw extruder. When it is in the second position, the blocking part is located inside the housing, so that the opening at the lower end of the housing is closed.

2. The screw extruder additive injection device according to claim 1, characterized in that, The drive assembly includes an adjusting bolt, a nut, an elastic element, and a first washer. The adjusting bolt is threaded to the upper end of the housing and can move along the height direction of the housing until it abuts against the lifting rod to push the lifting rod downward. The nut, elastic element, and first washer are all sleeved on the lifting rod. The nut is located above the first washer, and the first washer is fixedly installed inside the housing. One end of the elastic element abuts against the nut, and the other end of the elastic element abuts against the first washer.

3. The screw extruder additive injection device according to claim 2, characterized in that, The device further includes a second washer, which is sleeved on the outside of the lifting rod and located under the nut. One end of the elastic element abuts against the second washer.

4. The screw extruder additive injection device according to claim 1, characterized in that, The diameter of the blocking part gradually increases from top to bottom, or the diameter of the blocking part gradually decreases from top to bottom.

5. The screw extruder additive injection device according to claim 1, characterized in that, The lower end of the shell includes a first section, a second section, and a third section connected in sequence. The diameter of the second section is smaller than the diameter of the first section, and the diameter of the third section is smaller than the diameter of the second section. A third gasket is provided between the screw extruder and the outer periphery of the second section.

6. The screw extruder additive injection device according to claim 1, characterized in that, The housing includes an upper housing and a lower housing, which are detachably connected.

7. The screw extruder additive injection device according to claim 6, characterized in that, The diameter of the upper shell is larger than the diameter of the lower shell.

8. The screw extruder additive injection device according to claim 6, characterized in that, An insertion part is provided on one of the lower end of the upper shell and the upper end of the lower shell, and a recessed part is provided on the other for the insertion part to be inserted.

9. The screw extruder additive injection device according to claim 1, characterized in that, The housing has an auxiliary agent injection port that communicates with the inner channel, and the auxiliary agent injection port is located on the side of the housing.

10. The screw extruder additive injection device according to claim 1, characterized in that, The outer shell is provided with an external thread that connects to the screw extruder.

Images