Multilayer coextrusion blown film die

Abstract

The utility model discloses a multilayer co -extrusion blown film machine die head relates to plastic processing technical field, including a plurality of stacked disc piece, the inside of disc piece is provided with the inner core, and the outside of disc piece is provided with fastening structure, and fastening structure includes first fastening disc and second fastening disc, and first fastening disc and second fastening disc can hold and fix stacked disc piece, and the side of first fastening disc and second fastening disc adjacent is fixedly connected with first connecting block and second connecting block respectively, and the downside of first connecting block is rotatably connected with a plurality of inserting piece, and the second connecting block is opened and has inserted groove, and inserting piece and inserted groove are matched components, through first fastening disc and second fastening disc to disc piece stack whole clamping, and the compacting force evenly acts on the whole disc piece end face, and the disc piece bolt hole cracking problem caused by traditional bolt " single point stress " is thoroughly avoided, and the reliability and service life of die head are greatly improved.

Description

Technical Field

[0001] This utility model relates to the field of plastic processing technology, specifically a multi-layer co-extrusion blown film die head. Background Technology

[0002] In multi-layer co-extrusion blown film technology, the die head is the core component, which forms independent material flow channels by stacking multiple discs. Traditional die head disc stacking methods often use long bolts running through all the discs for locking and fixing. For example, the technical solution disclosed in the existing Chinese patent for a co-extrusion plastic blown film machine die head (CN221392250U) provides clamping force through circumferentially distributed bolts.

[0003] However, this bolted connection method has obvious defects: the clamping force generated by the bolts is concentrated around the bolt holes in a local area of ​​the disc, forming "single-point stress". Under long-term thermal cycling and mechanical stress, these stress concentration points are very prone to fatigue cracks, leading to disc damage, material leakage, and seriously affecting the die life and production safety.

[0004] Therefore, a multi-layer co-extrusion blown film die head is provided to solve the problems mentioned in the background art. Summary of the Invention

[0005] The purpose of this invention is to provide a multi-layer co-extrusion blown film die head to solve the problems mentioned in the background art.

[0006] To achieve the above objectives, this utility model provides the following technical solution:

[0007] A multi-layer co-extrusion blown film die head includes multiple stacked discs, each disc having an inner core and a fastening structure on its outer side. The fastening structure includes a first fastening disc and a second fastening disc, which can clamp and fix the stacked discs.

[0008] As a further embodiment of this utility model: wherein, a first connecting block and a second connecting block are fixedly connected to adjacent sides of the first fastening plate and the second fastening plate, respectively; a plurality of plug-in blocks are rotatably connected to the lower side of the first connecting block; and a plug-in groove is provided on the second connecting block, wherein the plug-in block and the plug-in groove are mating components.

[0009] As a further embodiment of this utility model: fastening plates are provided on the sides of both the first connecting block and the second connecting block, and multiple fastening frames are fixedly connected to the lower side of the fastening plates, the fastening frames clamping the first connecting block and the second connecting block.

[0010] As a further embodiment of this utility model: the fastening frame is provided with a slot, the slot and the plug-in block are mating components, and threaded holes are provided on both sides of the slot.

[0011] As a further embodiment of this utility model: wherein, a protrusion and a groove are respectively provided on the adjacent sides of the stacked disks, and the protrusion and groove are mating components.

[0012] As a further embodiment of this utility model: the inner core is provided with multiple heating elements, and a temperature controller is connected to the outside of the heating elements, the temperature controller adjusting the temperature of the multiple heating elements.

[0013] Compared with the prior art, the beneficial effects of this utility model are:

[0014] The first and second fastening discs clamp the stack of discs as a whole, and the clamping force is evenly applied to the entire end face of the discs. This completely avoids the problem of cracking of the disc bolt holes caused by the "single-point stress" of traditional bolts, and greatly improves the reliability and service life of the die head. Attached Figure Description

[0015] Figure 1 This is a schematic diagram of the overall structure of this utility model;

[0016] Figure 2 This is a schematic diagram of the first fastening disc structure in this utility model;

[0017] Figure 3 This is a schematic diagram of the fastening plate structure in this utility model;

[0018] Figure 4 This is a cross-sectional view of the inner core structure in this utility model;

[0019] The correspondence between the labels and component names in the attached figures is as follows:

[0020] 1. Disc; 101. Protrusion; 102. Groove; 2. Fastening structure; 201. First fastening disc; 202. Second fastening disc; 203. Fastening plate; 204. Fastening frame; 205. Threaded hole; 206. Slot; 207. Insertion slot; 208. Insertion block; 209. First connecting block; 210. Second connecting block; 3. Inner core; 4. Heating element. Detailed Implementation

[0021] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0022] Please see Figures 1-4 A multi-layer co-extrusion blown film die head includes multiple stacked discs 1. Each disc 1 has an inner core 3 inside and a fastening structure 2 on its outer side. The fastening structure 2 includes a first fastening disc 201 and a second fastening disc 202, which clamp and fix the stacked discs 1. In this embodiment, the first and second fastening discs 201 and 202 clamp the stacked discs 1 from both ends (top and bottom). The opposing pressure of the two fastening discs tightly fixes all the discs 1, and the resulting pressure acts on the entire end face of the disc 1 rather than a single point like the bolt hole. This arrangement fundamentally changes the stress distribution, transforming the "single-point stress" of the bolt into "uniform planar stress," directly solving the problem of stress concentration around the bolt hole in existing designs. It also provides a basic framework for subsequent graded fixing, ensuring the overall structural stability of the die head.

[0023] like Figure 2 and 3 As shown, a first connecting block 209 and a second connecting block 210 are fixedly connected to adjacent sides of the first fastening plate 201 and the second fastening plate 202, respectively. A plurality of plug-in blocks 208 are rotatably connected to the lower side of the first connecting block 209. The second connecting block 210 is provided with a plug-in groove 207. The plug-in block 208 and the plug-in groove 207 are mating components. In this embodiment, by rotating the plug-in block 208 on the first connecting block 209, the plug-in block 208 is aligned with the plug-in groove 207, and then inserted into the plug-in groove 207 of the second connecting block 210. After insertion, the plug-in block 208 is rotated again so that the plug-in block 208 is located on the bottom side of the plug-in groove 207 and is arranged in a "+" shape. This process does not require bolt tightening. The initial positioning of the two fastening plates is achieved only through mechanical fitting, avoiding additional stress caused by rigid compression.

[0024] Furthermore, fastening plates 203 are provided on the sides of both the first connecting block 209 and the second connecting block 210. Multiple fastening frames 204 are fixedly connected to the lower side of the fastening plates 203. The fastening frames 204 clamp the first connecting block 209 and the second connecting block 210. The fastening frames 204 have slots 206, which are mating components with the insertion block 208. Threaded holes 205 are provided on both sides of the slots 206. In this embodiment, after the insertion and positioning are completed, the fastening plates 203 with fastening frames 204 are placed on the outside of the two connecting blocks. The clamping force of the fastening frames 204 further restricts the displacement of the connecting blocks. The clamping force acts on the entire connecting block, rather than the single-point force of the bolt, and does not directly contact the disc 1 body. This setting enhances the connection strength on the basis of insertion and positioning, and at the same time disperses the stress to the contact surface between the fastening frames 204 and the connecting blocks, avoiding stress transmission to the disc 1. Compared with the bolts of the prior art that act directly on the disc 1, this further reduces the risk of cracking of the disc 1.

[0025] Specifically, after the slot 206 of the fastening frame 204 is aligned and engaged with the inserted plug block 208, the displacement of the fastening frame 204 is first restricted by mechanical engagement; then, the bolt is tightened through the threaded hole 205. At this time, the bolt stress only acts on the fastening frame 204 and the connecting block, and does not directly act on the disc 1. When disassembling, only the bolt needs to be unscrewed, without touching the disc 1. This setting not only ensures the stability of the fastening structure 2, but also isolates the bolt stress outside the disc 1, completely solving the problem of bolts directly damaging the disc 1 in the prior art.

[0026] Furthermore, each of the adjacent sides of the stacked disks 1 is provided with a protrusion 101 and a groove 102, which are mating components. In this embodiment, when stacking disks 1, the protrusions 101 and grooves 102 of adjacent disks 1 are precisely engaged to ensure that the central axis and material flow channel of each disk 1 are fully aligned, avoiding the disk 1 offset caused by non-positioning stacking in the prior art, and thus eliminating the need to forcibly correct misalignment with bolts to generate additional stress.

[0027] Specifically, a sealing groove is provided at the top of the protrusion 101 or the bottom of the groove 102, and a high-temperature resistant metal sealing ring (such as a spiral washer) is installed in the groove; under the clamping force of the fastening structure 2, the metal sealing rings between each disc 1 are pressed together to form a reliable end face seal and prevent material leakage.

[0028] like Figure 4As shown, the inner core 3 has multiple heating elements 4 inside, and a temperature controller is connected to the outside of the heating elements 4. The temperature controller regulates the temperature of the multiple heating elements 4. The inner core 3 has multiple heating elements 4 inside, and the temperature of each area is independently regulated by the temperature controller to ensure uniform temperature inside the die head. This avoids the difference in thermal expansion and contraction of the disc 1 caused by uneven temperature in the prior art, reduces the temperature stress caused by local overheating or overcooling, and complements the stress dispersion of the mechanical structure. In addition, the multiple heating elements 4 are arranged in zones along the material flow direction inside the inner core 3 (such as feeding zone, compression zone, and shaping zone), and each zone is independently and precisely controlled by the temperature controller.

[0029] Working principle: First, each disc 1 is precisely stacked using the protrusions 101 and grooves 102 on it, and a sealing ring is embedded. Then, the first fastening disc 201 and the second fastening disc 202 are placed at both ends of the stack. The insertion block 208 on the first connecting block 209 is rotated to align with and insert into the insertion slot 207 on the second connecting block 210. Then, the insertion block 208 is rotated in the opposite direction to achieve mechanical interlocking and complete the initial rapid positioning. After that, the fastening plate 203 and the fastening frame 204, which are divided into two halves, are closed so that the slot 206 is engaged with the insertion block 208. Finally, the threaded hole 205 is tightened with a bolt to complete the final locking. During operation, the partitioned heating plate 4 in the inner core 3 is precisely temperature-controlled by a temperature controller to ensure material flowability and film quality. The entire system is subjected to uniform force and has reliable connection, which greatly improves the performance and service life of the equipment.

[0030] The above description is only a preferred embodiment of the present utility model, but the protection scope of the present utility model is not limited thereto. Any equivalent substitutions or changes made by those skilled in the art within the technical scope disclosed in the present utility model, based on the technical solution and the inventive concept of the present utility model, should be included within the protection scope of the present utility model.

Claims

1. A multi-layer co-extrusion blown film die head, comprising multiple stacked discs (1), wherein an inner core (3) is disposed inside the discs (1), characterized in that, The outer side of the disk (1) is provided with a fastening structure (2), which includes a first fastening plate (201) and a second fastening plate (202). The first fastening plate (201) and the second fastening plate (202) can clamp and fix the stacked disks (1).

2. The multi-layer co-extrusion blown film die head according to claim 1, characterized in that, The first fastening plate (201) and the second fastening plate (202) are respectively fixedly connected to a first connecting block (209) and a second connecting block (210) on their adjacent sides. The lower side of the first connecting block (209) is rotatably connected to a plurality of plug-in blocks (208). The second connecting block (210) is provided with a plug-in groove (207). The plug-in block (208) and the plug-in groove (207) are mating components.

3. The multi-layer co-extrusion blown film die head according to claim 2, characterized in that, The first connecting block (209) and the second connecting block (210) are provided with fastening plates (203) on their sides. Multiple fastening frames (204) are fixedly connected to the lower side of the fastening plates (203), and the fastening frames (204) clamp the first connecting block (209) and the second connecting block (210).

4. The multi-layer co-extrusion blown film die head according to claim 3, characterized in that, The fastening frame (204) has a slot (206) and the plug block (208) are mating components. Threaded holes (205) are provided on both sides of the slot (206).

5. The multi-layer co-extrusion blown film die head according to claim 1, characterized in that, The stacked disks (1) are provided with a protrusion (101) and a groove (102) on the adjacent side respectively, and the protrusion (101) and the groove (102) are mating components.

6. The multi-layer co-extrusion blown film die head according to claim 1, characterized in that, The inner core (3) is provided with multiple heating elements (4), and a temperature controller is connected to the outside of the heating elements (4). The temperature controller adjusts the temperature of the multiple heating elements (4).

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