New EPE sheet forming mold and EPE hollow sheet preparation method

Abstract

The present invention relates to the field of mold technology, and in particular to a new type of EPE sheet forming mold and a preparation method of an EPE hollow plate, comprising a concave mold and a convex mold, wherein the discharge end of the concave mold cooperates with the extrusion end of the convex mold so that the molten material is extruded through the gap between the two; the extrusion end has a plurality of circumferentially arranged concave-convex structures in the radial direction, and the depth of the concave-convex structure deepens radially outward, so that the cross section of the extruded EPE sheet is spindle-shaped. The present invention arranges a concave-convex structure at the extrusion end of the convex mold so that the molten material forms a new type of EPE sheet with a spindle-shaped cross section after being deformed by the concave-convex structure; the spindle-shaped sheet is composited to form an EPE sheet, and there is a gap inside the sheet, so that the butane remaining inside the sheet can be released faster, and the basic needs of existing logistics packaging are met, and the mechanical properties of the material are further improved, which is conducive to saving materials and reducing costs.

Description

Technical Field

[0001] The invention relates to the technical field of molds, and in particular to a sheet forming mold and a preparation method of a novel EPE sheet and a hollow plate. Background Art

[0002] EPE (expanded polyethylene) is a new type of environmentally friendly packaging material, also known as pearl cotton. It is light and has good cushioning properties. It can achieve higher mechanical properties at a lower density. Therefore, it is widely used around the world, especially in logistics packaging. In the prior art, a round-mouthed straight mold is usually used to mass-produce low-density, low-thickness flat coils. After a period of curing and shaping, some coils are directly cut into gaskets or cover plates for packaging, and some coils are cut into sheets and then compound thickened to prepare plates of different thicknesses. The plates are then customized for cushioning packaging by slitting, die-cutting, bonding, etc., which are widely used in the internal protection of logistics packaging for many categories of products such as electronic appliances, auto parts, and fresh agricultural products.

[0003] For example, patent number CN104690875A, whose name is "A production mold for flat pearl cotton" and whose publication date is June 10, 2015, discloses a production mold for flat pearl cotton. The two ends of the male mold are respectively an installation end and a working end, the middle part of the working end protrudes outward to form a protrusion, and an inclined surface is arranged between the protrusion and the outer periphery of the working end; the two ends of the female mold are respectively a feeding end and a discharging end, the feeding end is provided with a feeding port, the discharging end is provided with a discharging port, the discharging port is connected with the feeding port, an outer chamfer is arranged on the outer side of the discharging end, and an inner chamfer is arranged on the inner side of the discharging port; when the working end of the male mold is matched with the discharging end of the female mold and installed, the protrusion of the male mold extends into the discharging port of the female mold, a first angle α is formed between the inner chamfer of the female mold and the inclined surface of the male mold, and a second angle β is formed between the outer chamfer of the female mold and the inclined surface of the male mold.

[0004] The above patent can improve the flatness of the material, but when the coiled material made by the above mold is placed in a warehouse for curing and shaping, due to the flat structure of the thin sheets, there is no gap between them, and the butane added during the preparation process cannot be released quickly. Therefore, a longer curing cycle is required, which also leads to a longer production cycle and reduced production efficiency. Summary of the invention

[0005] In order to solve the problem of blocked butane release space during curing of existing EPE coils mentioned in the above-mentioned prior art, the present invention provides a new type of EPE sheet forming mold, including a concave mold and a convex mold, the discharge end of the concave mold is in an inner chamfered shape, and the extrusion end of the convex mold is in an outer chamfered shape, the discharge end cooperates with the extrusion end so that the molten material is extruded through the gap between the two; the extrusion end is provided with a plurality of circumferentially arranged concave-convex structures in the radial direction, and the depth of the concave-convex structure deepens radially outward, so that the cross-section of the extruded EPE sheet is spindle-shaped.

[0006] Furthermore, it also includes a fixed disc, which is used to fix the concave mold on the frame.

[0007] Furthermore, the inner cavity of the concave mold is funnel-shaped.

[0008] Furthermore, it also includes a core shaft, which is sequentially sleeved on the concave mold and the convex mold.

[0009] Furthermore, it also includes an adjusting nut, which is used to adjust the distance between the concave mold and the convex mold.

[0010] The present invention also provides a method for preparing a novel EPE hollow sheet, comprising the following steps:

[0011] S100, mixing the prepared raw materials in a certain proportion, conveying them to the high temperature section of the foaming main machine through a feeder for melting, adding an anti-shrinkage agent and a foaming agent to mix with the raw materials, cooling them through a low temperature section cooling system, and then extruding them through the EPE sheet forming die as described above to form a new EPE sheet with a spindle-shaped cross section and winding the new EPE sheet;

[0012] S200, health and shaping of the rolled new EPE sheet;

[0013] S300, using EPE sheet compounding equipment to compound the new EPE sheet after curing and shaping, and compounding the new EPE sheet to a required thickness to obtain a new EPE hollow sheet.

[0014] Furthermore, the step of rolling up the novel EPE sheet comprises the following steps:

[0015] S110, after the extruded annular new EPE sheet is passed through a shaping drum to set the width, it is cut by a cutting mechanism;

[0016] S120, pulling the cut new EPE sheet onto the heat dissipation component to unfold and dissipate heat, and then rolling it up.

[0017] A novel EPE sheet forming die provided by the present invention has the following advantages compared with the prior art: by arranging a plurality of circumferentially arranged concave-convex structures at the extrusion end of a convex die, the molten material is deformed by the concave-convex structures to form a novel EPE sheet with a spindle-shaped cross section; after the spindle-shaped EPE sheet is compounded to form an EPE plate, there are many gaps inside the plate, which, on the one hand, provides space for the release of foaming polymer butane, thereby accelerating the production cycle; on the other hand, it can not only meet the basic needs of existing logistics packaging, but also further provide mechanical properties such as material compression and elastic recovery rate, which is conducive to saving materials and reducing costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following drawings required for use in the embodiments or the prior art description are described. Do A brief introduction, it is obvious that the drawings described below are some embodiments of the present invention, for ordinary technicians in this field, without paying creative labor, other drawings can be obtained based on these drawings.

[0019] Figure 1 A front view of a novel EPE sheet forming mold provided by the present invention;

[0020] Figure 2 for Figure 1 Sectional view of AA in the middle;

[0021] Figure 3 It is a schematic diagram of the structure of the convex mold;

[0022] Figure 4 for Figure 3 A partial enlarged view of middle A;

[0023] Figure 5 Schematic diagram of the cross section of the generated new EPE sheet;

[0024] Figure 6 A schematic diagram of a mold structure of another embodiment provided by the present invention;

[0025] Figure 7 An exploded view of a mold structure of another embodiment provided by the present invention;

[0026] Figure 8 It is a structural schematic diagram of a foaming machine using the mold provided by the present invention;

[0027] Fig. 9 It is a schematic diagram of the cross section of the composite new EPE hollow sheet;

[0028] Fig.10It is a schematic cross-sectional view of other embodiments of the novel composite EPE hollow sheet.

[0029] Reference numerals:

[0030] 110 concave mold 120 convex mold 111 discharge end

[0031] 121 extrusion end 122 concave-convex structure 130 fixed disc

[0032] 140 spindle 150 adjustment nut 210 foaming host

[0033] 220 shaping and cutting assembly 230 heat dissipation assembly 240 traction and winding assembly

[0034] 221 shaping drum 222 cutting mechanism DETAILED DESCRIPTION

[0035] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0036] In the description of the present invention, it should be noted that the terms "center", "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first" and "second" are used for descriptive purposes only and cannot be understood as indicating or implying relative importance.

[0037] The present invention provides a novel EPE sheet molding mold, comprising a concave mold 110 and a convex mold 120, wherein a discharge end 111 of the concave mold 110 is in an inner chamfered shape, and an extrusion end 121 of the convex mold 120 is in an outer chamfered shape, and the discharge end 111 cooperates with the extrusion end 121 so that a molten material is extruded through a gap between the two; the extrusion end 121 is provided with a plurality of circumferentially arranged concave-convex structures 122 in a radial direction, and the depth of the concave-convex structures 122 increases radially outward, so that the cross section of the extruded EPE sheet is spindle-shaped.

[0038] When implementing it, Figures 1 to 5As shown, the mold for forming the novel EPE sheet includes a concave mold 110 with an inner chamfer 111 at the discharge end and a convex mold 120 with an outer chamfer 121 at the extrusion end; preferably, as Figure 3 As shown, the radial angle α between the outer chamfered inclined surface of the convex mold 120 and the convex mold 120 is in the range of 15° to 25°. Studies have found that the die head pressure of the mold with an angle range between these is more stable during EPE sheet molding. Figures 3-4 As shown, the convex mold 120 is provided with a plurality of circumferentially arranged concave-convex structures 122 in the radial direction, and the depth of the concave-convex structures 122 increases radially outward. It should be understood that the shape of the concave-convex structures 122 is not limited to the following. Figure 4 The rectangular concave-convex structure shown, according to the concept of the present invention, those skilled in the art can also replace the shape of the concave-convex structure 122 of the present invention with other structures that can make the cross section of the extruded EPE sheet spindle-shaped, such as arc-shaped concave-convex structure, triangular concave-convex concave-convex, trapezoidal concave-convex structure, etc. Preferably, the arrangement angle formed by each adjacent concave-convex structure 122 is between 3° and 45°. The EPE sheet formed by the mold whose adjacent concave-convex structure 122 is arranged at an angle less than 3° is not effective in releasing butane when it is compounded into an EPE sheet, and the EPE sheet formed by the mold whose adjacent concave-convex structure 122 is arranged at an angle greater than 45° is relatively insufficient in strength and performance when it is compounded into an EPE sheet; therefore, for conventional molds on the market, the EPE sheet formed by the arrangement angle between this range is easier to form with regular corrugations in the shape of a spindle, and the performance of the corrugations is better, and the butane release effect is better.

[0039] Its working principle is that the molten material is squeezed out from the closing gap of the mold under the combined action of the driving force and the pulling force, and the molten material is deformed by the concave-convex structure 122, and foams and expands due to the pressure difference change, and finally forms a new EPE sheet with a spindle-shaped cross section. The convex parts of the upper and lower surfaces of the spindle-shaped new EPE sheet are symmetrical arc-shaped, so that the sheet can absorb higher energy during the compression deformation process. Compared with ordinary flat EPE sheets or EPE sheets with irregular upper and lower surfaces, it has a higher elastic recovery rate and the bonding strength will not be reduced.

[0040] The novel EPE sheet forming die provided by the present invention provides a plurality of circumferentially arranged concave-convex structures at the extrusion end of the convex die, so that the molten material is deformed by the concave-convex structures to form a novel EPE sheet with a spindle-shaped cross section; after the spindle-shaped EPE sheet is compounded to form an EPE plate, there are many gaps inside the plate, on the one hand, providing space for the release of residual butane in the foaming polymer, thereby accelerating the production cycle; on the other hand, it can not only meet the basic needs of existing logistics packaging, but also further improve the mechanical properties of the material such as compression and elastic recovery rate, which is conducive to reducing the use of materials and reducing costs.

[0041] Preferably, a fixed disc 130 is further included, and the fixed disc 130 is used to fix the concave mold 110 on the frame.

[0042] When implementing it, Figures 6-7 As shown, the fixing disc 130 is provided with a plurality of through holes, and the concave mold 110 can be fixed on the frame by threaded connection, or by other detachable methods such as clamping, pin connection, etc.

[0043] Preferably, the inner cavity of the concave mold 110 is funnel-shaped.

[0044] When implementing it, Figure 2 As shown, the inner cavity of the concave mold 110 is funnel-shaped, that is, the inner cavity of the concave mold 110 narrows along the discharge end 111, which not only facilitates the conveying of materials, but also achieves the purpose of pressurizing at the discharge port, which is beneficial to the extrusion molding of materials.

[0045] Preferably, it also includes a core shaft 140, and the core shaft 140 is sequentially sleeved on the concave mold 110 and the convex mold 120.

[0046] Preferably, an adjusting nut 150 is further included, and the adjusting nut 150 is used to adjust the distance between the concave mold 110 and the convex mold 120.

[0047] When implementing it, Figures 6-7 As shown, according to work requirements, the adjusting nut 150 is used to adjust the distance between the concave mold 110 and the convex mold 120 to adjust the closing gap when the concave mold 110 and the convex mold 120 cooperate, so as to obtain EPE sheets of different thicknesses without changing the mold, which increases practicality and improves production efficiency. As a preferred solution, the end of the mandrel 140 is provided with a thread, and the adjusting nut 150 is threadedly connected to the mandrel 140 to adjust the distance.

[0048] By applying the mold for forming the new EPE sheet as described above to the foaming machine equipment, a new EPE sheet with a spindle-shaped cross-section can be processed, so that the new EPE sheet material consumption is small and the residual butane is completely released during the curing process. After being compounded to form an EPE board, it has a regular and stable structure, so that the material has good buffering and seismic isolation properties.

[0049] When implementing it, Figure 8 As shown, the foaming main unit 210 is provided with an anti-shrinkage agent injection port, a foaming agent injection port and a cooling system. After the prepared raw materials are melted at high temperature in the foaming main unit 210, the anti-shrinkage agent and the foaming agent are injected into the foaming main unit 210 through the injection port to mix with the raw materials, and are cooled by the cooling system in the low-temperature section of the main unit. The discharge port of the low-temperature section is connected to the mold, and a new EPE sheet with a spindle-shaped cross-section is formed by extrusion through the mold, and then the width is fixed and cut through the shaping and cutting component 220, and finally the heat dissipation and winding are carried out through the heat dissipation component 230 and the traction and winding component 240, so as to obtain a new EPE coil.

[0050] Preferably, the shaping and cutting assembly 220 includes a shaping drum 221 for shaping the width of the EPE sheet and a cutting mechanism 222 for cutting the annular EPE sheet.

[0051] When implementing it, Figure 8 As shown, the shaping and cutting assembly 220 includes a shaping drum 221 for fixing the width of the EPE sheet and a cutting mechanism 222 for cutting the annular EPE sheet. The shaping drum 221 is provided with an air cooling and water cooling device for shaping by air cooling and water cooling. The cutting mechanism 222 is arranged at the tail of the shaping drum 221, including an air knife, a driving device and a connecting part, which can split the shaped annular EPE sheet.

[0052] The present invention also provides a method for preparing a novel EPE hollow sheet, comprising the following steps:

[0053] S100, mixing the prepared raw materials in a certain proportion, conveying them to the high temperature section of the foaming main machine through a feeder for melting, adding an anti-shrinkage agent and a foaming agent to mix with the raw materials, cooling them through a low temperature section cooling system, and then extruding them through the EPE sheet forming die as described above to form a new EPE sheet with a spindle-shaped cross section and winding the new EPE sheet;

[0054] S200, health and shaping of the rolled new EPE sheet;

[0055] S300, using EPE sheet compounding equipment to compound the new EPE sheet after curing and shaping, and compounding the new EPE sheet to a required thickness to obtain a new EPE hollow sheet.

[0056] In specific implementation, the preparation method of the EPE hollow sheet is completed through the above steps. Preferably, the temperature of the molten mixture at the die extrusion port is set between 90°C and 120°C. The molten mixture in this temperature range has better fluidity, so that the extruded EPE sheet has better molding effect. As another embodiment, when the α angle of the convex mold is 15° to 25° and the temperature of the molten mixture at the die extrusion port is set to 90°C to 120°C, the fluidity of the molten mixture at the die extrusion port is optimal, and the extruded EPE sheet has the best molding effect, so that the mechanical properties of the final composite EPE hollow sheet are optimal. Fig. 9 The figure shows a schematic cross-sectional view of a new type of EPE hollow plate. By compounding the new type of EPE sheets to form a plate, the internal buffer space between the plates is made larger, which greatly saves materials. In the preparation process, it can ensure that there is enough space for the residual butane to be released, thereby improving production efficiency, and at the same time, there are regularly arranged gaps so that the difficulty of compounding the two and the bonding strength will not increase. As a preferred embodiment, multiple layers of the new type of EPE sheets can be cross-stacked and compounded with multiple layers of ordinary flat EPE sheets, as shown in Figure 10 for the various compounding forms listed. It should be noted that, on the one hand, its cross-compounding method is not limited to the following. Fig.10 As shown, it can be freely matched according to actual working conditions; on the other hand, Fig.10 The composite forms listed here only represent the cross-over method, not the final structure of the composite board, that is, according to the requirements of different board heights in actual work, they can be repeatedly cross-stacked until the ideal height. Compared with ordinary EPE and its products, the EPE board and its products with the same thickness and density improved by the present invention have a shorter production cycle, lighter weight, less material consumption, and better buffering properties such as compression resistance, impact resistance, and shock resistance.

[0057] Preferably, the step of winding the novel EPE sheet comprises the following steps:

[0058] S110, after the extruded annular new EPE sheet is passed through a shaping drum to set the width, it is cut by a cutting mechanism;

[0059] S120, pulling the cut new EPE sheet onto the heat dissipation component to unfold and dissipate heat, and then rolling it up.

[0060] Although the terms such as concave mold, convex mold, discharge end, extrusion end, concave-convex structure, fixed disc, mandrel, adjusting nut, foaming main machine, shaping and cutting assembly, heat dissipation assembly, traction and winding assembly, shaping drum, cutting mechanism, etc. are used more frequently in this article, the possibility of using other terms is not excluded. The use of these terms is only for more convenient description and explanation of the essence of the present invention; interpreting them as any additional limitation is contrary to the spirit of the present invention.

[0061] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein by equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A novel EPE sheet forming mold, comprising a concave mold (110) and a convex mold (120), characterized in that: The discharge end (111) of the concave die (110) is in an inner chamfered shape, and the extrusion end (121) of the convex die (120) is in an outer chamfered shape. The discharge end (111) cooperates with the extrusion end (121) so that the molten material is extruded through a gap between the two ends. The extrusion end (121) is provided with a plurality of circumferentially arranged concave-convex structures (122) in a radial direction, and the depth of the concave-convex structures (122) increases radially outward, so that the cross section of the extruded EPE sheet is spindle-shaped. The arrangement angle formed by each adjacent concave-convex structure (122) is between 3° and 45°.

2. The novel EPE sheet forming mold according to claim 1 further comprises a fixed disc (130), characterized in that: The fixed disc (130) is used to fix the concave mold (110) on a frame.

3. A new type of EPE sheet forming mold according to claim 1, characterized in that: The inner cavity of the concave mold (110) is funnel-shaped.

4. A new type of EPE sheet forming mold according to any one of claims 1 to 3, further comprising a mandrel (140), characterized in that: The core shaft (140) is sequentially sleeved on the concave mold (110) and the convex mold (120).

5. The novel EPE sheet forming mold according to claim 4 further comprises an adjusting nut (150), characterized in that: The adjusting nut (150) is used to adjust the distance between the concave mold (110) and the convex mold (120).

6. A method for preparing a novel EPE hollow sheet, characterized in that: The following steps are involved: S100, mixing the prepared raw materials in a certain proportion, conveying them to the high temperature section of the foaming main machine through a feeder for melting, adding an anti-shrinkage agent and a foaming agent to mix with the raw materials, cooling them through a low temperature section cooling system, and then extruding them through a die formed by the EPE sheet according to any one of claims 1 to 5 to form a new EPE sheet with a spindle-shaped cross section and winding the new EPE sheet; S200, health and shaping of the rolled new EPE sheet; S300, using EPE sheet compounding equipment to compound the new EPE sheet after curing and shaping, and compounding the new EPE sheet to a required thickness to obtain a new EPE hollow sheet.

7. The method for preparing a novel EPE hollow sheet according to claim 6, characterized in that: The step of winding up the novel EPE sheet comprises the following steps: S110, after the extruded annular new EPE sheet is passed through a shaping drum to set the width, it is cut by a cutting mechanism; S120, pulling the cut new EPE sheet onto the heat dissipation component to unfold and dissipate heat, and then rolling it up.

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