Mould for hot bending forming of IML (in-mold labeling) diaphragm and hot bending forming equipment

Abstract

The invention provides a mold for hot bending forming of an IML diaphragm and hot bending forming equipment, an upper mold of the mold comprises an upper mold core, the bottom surface of the upper mold core is provided with two bending parts which protrude downwards and are distributed at intervals, and thus a U-shaped first cavity is formed between the two bending parts. The lower die comprises a base, a lower die core, a placing platform and a lifting mechanism, the lower die core is provided with a second cavity with an upward opening, a lifting channel is arranged between the bottom wall of the second cavity and the bottom surface of the lower die core, and the placing platform is used for placing a diaphragm and is located in the lifting channel. The lifting mechanism drives the placing platform to ascend or descend. The diaphragm is subjected to hot bending forming through the mold, the problem that patterns or characters on the edges of the two sides of the diaphragm are subjected to tensile deformation is effectively solved, the middle area of the diaphragm can be protected, scratches, deformation, pocking marks and other poor processes are reduced, energy is saved, and the material cost of product makeup is reduced.

Description

Technical Field

[0001] The present application belongs to the field of IML process technology, and more specifically, relates to a mold and a hot bending forming device for IML diaphragm hot bending forming. Background Art

[0002] PC+PMMA composite sheet is a composite material made of polycarbonate (PC) and polymethyl methacrylate (PMMA) through co-extrusion process. This composite sheet has the advantages of high hardness and high wear resistance of PMMA material and the advantages of strong toughness and good formability of PC material. It also has excellent light transmittance and transparent glass-like effect. It is widely used in electronic product housings, automotive interiors, wearable devices, smart furniture and other equipment. PC+PMMA composite sheet is usually combined with the plastic surface by IML (In Molding Label) process to become a surface decorative protective film with wear resistance and scratch resistance.

[0003] The specific steps of the IML process are as follows: first, the PC+PMMA composite sheet is cut into films of predetermined shapes and sizes; then, a layer with patterns or texts is formed on the film by printing, electroplating, etc. according to the appearance of the product; then, the film is formed into a 3D shape according to the shape of the product; after forming, the excess material at the edge of the film is cut off; finally, the film is placed in an injection mold for injection molding, so that the molten plastic raw material fills the mold and is tightly combined with the film to form the final product.

[0004] For diaphragms made of PC+PMMA composite materials, high-pressure vacuum molding is usually used for 3D molding. However, this molding method has requirements for the position of the pattern or text on the diaphragm. The pattern or text cannot be too close to the edge of the diaphragm, otherwise it will be pulled and deformed, thus affecting the molding quality and reducing the production yield. Summary of the invention

[0005] The purpose of the embodiments of the present application is to provide a mold and a hot bending forming device for IML diaphragm hot bending forming, so as to solve the technical problem in the prior art that when a diaphragm made of PC+PMMA composite material is 3D formed by high-pressure vacuum suction forming, the pattern or text at the edge position will be stretched and deformed.

[0006] To achieve the above-mentioned purpose, the technical solution adopted in the present application is: to provide a mold for hot bending of IML diaphragms, the mold comprising an upper mold and a lower mold. The upper mold comprises an upper mold core, and the bottom surface of the upper mold core is provided with two bending parts protruding downward and spaced apart, so as to form a U-shaped first cavity between the two bending parts. The lower mold comprises a base, a lower mold core, a placement platform and a lifting mechanism, the lower mold core and the lifting mechanism are both installed on the base, the lower mold core has a second cavity opening upward, and there is a lifting channel between the bottom wall of the second cavity and the bottom surface of the lower mold core, and the placement platform is used to place the diaphragm and is located in the lifting channel. The lifting mechanism drives the placement platform to rise so that the top surface of the placement platform is higher than the bottom wall of the second cavity, and a third cavity is formed between the placement platform and the inner walls on both sides of the cavity, the placement platform matches the shape of the first cavity, and the bending part matches the shape of the third cavity; or, the lifting mechanism drives the placement platform to descend so that the top surface of the placement platform and the bottom wall of the cavity are located in the same plane.

[0007] In one embodiment, the lower mold core is made of graphene material, and the thermal conductivity of the lower mold core is greater than the thermal conductivity of the placement platform.

[0008] In one embodiment, the upper mold core includes a middle block and two heating blocks, the two heating blocks are respectively fixed on both sides of the middle block, and the two bending parts are respectively located at the bottom of the two heating blocks; the two heating blocks are made of graphene material, and the thermal conductivity of the heating blocks is greater than the thermal conductivity of the middle block.

[0009] In one embodiment, a top surface of the placement platform and a bottom surface of the middle block are respectively provided with a silicone layer.

[0010] In one embodiment, the placement platform is provided with a plurality of negative pressure channels distributed at intervals, so that the membrane can be adsorbed on the surface of the placement platform.

[0011] In one embodiment, the lower mold core has two bosses, which are integrally extended upward from two side edges of the second cavity; the upper mold core correspondingly has two grooves, which cooperate with the bosses.

[0012] In one embodiment, the mold includes a heating device, and the upper mold core and the lower mold core are respectively connected to the heating device.

[0013] In one embodiment, the heating device includes an upper heating plate and a lower heating plate, wherein the upper heating plate is fixedly mounted on the top surface of the upper mold core, and the lower heating plate is fixedly mounted on the bottom surface of the lower mold core.

[0014] In one embodiment, the heating device is a plurality of heating rods, and the upper mold core and the lower mold core are both provided with a plurality of heating channels distributed at intervals, and the heating rods are installed in each heating channel in a one-to-one correspondence.

[0015] According to another aspect of the present application, the present application further provides a hot bending forming device, which includes the mold, machine body and mold clamping robot of any one of the above items, the machine body is provided with a heating zone and a cooling zone, the mold and the mold clamping robot are installed on the machine body, and the mold clamping robot is used to move the mold between the heating zone and the cooling zone.

[0016] The beneficial effects of the mold for hot bending forming of IML diaphragms provided in the present application are: compared with the prior art, the mold provided in the present application bends and forms the two side areas of the diaphragm, and will not cause pulling deformation to the pattern or text at the edge of the diaphragm, effectively solving the problem of stretching and deformation of the pattern or text at the edge of the diaphragm when high-pressure vacuum suction forming is used in the prior art, thereby improving the product yield and reducing the diaphragm scrap rate and production cost; secondly, the mold provided in the present application sets a lifting channel in the lower mold core, so that the placement platform can be lifted and moved along the lifting channel under the drive of the lifting mechanism, so that when the placement platform is lowered to a predetermined position, the diaphragm can be placed on the plane formed by the placement platform and the bottom wall of the second cavity for heating. In this way, when the lower mold core is heated, due to the gap between the placement platform and the lower mold core, the temperature of the placement platform surface will be lower than the bottom wall temperature of the second cavity, so that the heating rate and temperature of the middle area of ​​the diaphragm are lower than the areas on both sides of the diaphragm, so that the areas on both sides of the diaphragm that need to be bent can be bent after reaching the softening temperature, while the middle area of ​​the diaphragm that does not need to be bent will not reach the softening temperature, which is beneficial to protect the middle area of ​​the diaphragm, reduce the occurrence of scratches, deformations, pitting and other process defects, and reasonably use heat, save energy, and facilitate faster cooling of the diaphragm after forming. Third, the use of the mold and hot bending forming equipment can further effectively utilize the product plate, greatly save the material cost of the product plate, and is conducive to mass production. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0018] Figure 1 A schematic diagram of the three-dimensional structure of a mold provided in an embodiment of the present application; Figure 2 A schematic diagram of the three-dimensional structure of the upper mold core of the mold provided in an embodiment of the present application in an inverted state; Figure 3 A cross-sectional view of a mold provided by an embodiment of the present application, wherein the top surface of the placement platform and the bottom wall of the cavity are located in the same plane; Figure 4 A cross-sectional view of a mold provided in an embodiment of the present application, wherein the top surface of the placement platform is higher than the bottom wall of the cavity.

[0019] Among them, the reference numerals in the figure are: 10-upper mold; 11-upper mold core; 1101-first cavity; 1102-groove portion; 111-bending portion; 112-middle block; 113-heating block; 20-lower mold; 21-base; 22-lower mold core; 2201-second cavity; 2202-lifting channel; 2203-third cavity; 221-boss portion; 23-placing platform; 24-lifting mechanism; 30-heating device; 31-upper heating plate; 32-lower heating plate; 300-diaphragm. DETAILED DESCRIPTION

[0020] In order to make the technical problems, technical solutions and beneficial effects to be solved by the present application more clearly understood, the present application is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

[0021] It should be noted that when an element is referred to as being "fixed to" or "disposed on" another element, it can be directly on the other element or indirectly on the other element. When an element is referred to as being "connected to" another element, it can be directly connected to the other element or indirectly connected to the other element.

[0022] It should be understood that the terms "length", "width", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating the orientation or position relationship, are based on the orientation or position relationship shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present application.

[0023] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of this application, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0024] Please also read Figures 1 to 4, the mold for hot bending forming of IML diaphragms provided in the embodiment of the present application is now described. The mold includes an upper mold 10 and a lower mold 20. The upper mold 10 includes an upper mold core 11, which is roughly a rectangular block, wherein the bottom surface of the upper mold core 11 is provided with two bending portions 111 protruding downward and spaced apart, and the two bending portions 111 are long convex ribs extending downward from the bottom surface of the upper mold core 11, respectively, so as to form a U-shaped first cavity 1101 between the two bending portions 111, and the first cavity 1101 opens downward.

[0025] The lower mold 20 includes a base 21, a lower mold core 22, a placement platform 23 and a lifting mechanism 24. The base 21 is used to support the lower mold core 22, the placement platform 23 and the lifting mechanism 24. In actual production, the entire lower mold 20 is fixedly mounted on the machine platform through the base 21. The lower mold core 22 is mounted on the base 21, and the lower mold core 22 has a second cavity 2201 with an opening facing upward. There is a lifting channel 2202 between the bottom wall of the second cavity 2201 and the bottom surface of the lower mold core 22. The placement platform 23 is used to place the diaphragm and is located in the lifting channel 2202. One end of the lifting mechanism 24 is fixedly mounted on the base 21, and the other end of the lifting mechanism 24 is connected to the bottom surface of the placement platform 23 and can operably drive the lifting mechanism 24 to rise or fall along the lifting channel 2202.

[0026] Specifically, the placement platform 23 has two states. In the first state, the lifting mechanism 24 drives the placement platform 23 to descend, so that the top surface of the placement platform 23 and the bottom wall of the second cavity 2201 are located in the same plane. Figure 3 As shown, at this time, the membrane to be formed can be placed on the plane formed by the placement platform 23 and the bottom wall of the second cavity 2201 for heating.

[0027] In the second state, the lifting mechanism 24 drives the placement platform to rise, so that the top surface of the placement platform 23 is higher than the bottom wall of the second cavity 2201. Figure 1 and Figure 4 As shown, at this time, the third cavity 2203 is formed between the placement platform 23 and the inner walls on both sides of the second cavity 2201. It can be understood that the two third cavities 2203 are respectively located on both sides of the placement platform 23, and the third cavity 2203 is equivalent to a part of the second cavity 2201. The shape of the placement platform 23 matches the shape of the first cavity 1101, and the bending portion 111 matches the shape of the third cavity 2203, so that the upper mold core 11 and the lower mold core 22 can be molded together, so that the placement platform 23 enters the first cavity 1101, and the two bending portions 111 enter the third cavity 2203 respectively, and the gap between the placement platform 23 and the inner wall of the first cavity 1101 forms a cavity for molding the diaphragm.

[0028] The working process of the mold is as follows: first, open the upper and lower molds of the mold, install the upper mold 10 and the lower mold 20 on the machine respectively, and align the upper mold core 11 and the lower mold core 22. Drive the placement platform 23 down through the lifting mechanism 24, so that the top surface of the placement platform 23 and the bottom wall of the second cavity 2201 are located in the same plane. Then place the diaphragm 300 to be formed on the plane formed by the top surface of the placement platform 23 and the bottom wall of the second cavity 2201. At this time, most of the middle area of ​​the diaphragm 300 is located on the placement platform 23, and the two side areas of the diaphragm 300 are respectively located on the bottom wall of the second cavity 2201. Then the machine will heat the upper mold core 11 and the lower mold core 22, and the heat will be transferred to the diaphragm 300. After the diaphragm 300 begins to soften, the lifting mechanism 24 drives the placement platform 23 to rise to a predetermined position, so that the top surface of the placement platform 23 is higher than the bottom wall of the second cavity 2201. At this time, the two side areas of the diaphragm 300 are suspended on the two side edges of the placement platform 23. Then, as the upper mold core 11 is gradually pressed down and closed with the lower mold core 22, the two bending parts 111 of the upper mold core 11 contact the two side areas of the diaphragm 300 and press down and bend the diaphragm 300 until the upper mold core 11 and the lower mold core 22 are completely closed. The diaphragm 300 is bent into shape. At this time, the diaphragm 300 is located in the gap between the inner wall of the first cavity 1101 and the top surface of the placement platform 23, as shown in FIG. Figure 4 Finally, the mold is cooled by the cooling system of the machine, so that the diaphragm 300 is cooled and shaped, and then the mold is opened to take out the diaphragm 300.

[0029] Compared with the prior art, the mold for IML diaphragm hot bending molding provided in the present application is formed by bending the two side areas of the diaphragm 300, so that during the 3D molding process of the diaphragm, the pattern or text at the edge of the diaphragm 300 will not be pulled and deformed, which effectively solves the problem of the pattern or text at the edge of the diaphragm being stretched and deformed when high-pressure vacuum suction molding is used in the prior art, thereby improving the product yield and reducing the diaphragm scrap rate and production cost; In addition, it is understandable that if the placement platform 23 and the lower mold core 22 are an integrated structure that cannot move relative to each other, then the temperature of the two after the machine is heated and heated is the same. In order for the diaphragm 300 to be bent and formed, the height of the placement platform 23 needs to be higher than the bottom wall of the second cavity 2201. In this way, when the diaphragm 300 is placed on the placement platform 23 for heating and softening, the two side areas of the diaphragm 300 that need to be heated, softened and bent will be suspended on the two side edges of the placement platform 23, and the heating speed is slow; while the middle area of ​​the diaphragm 300 that does not need to be heated, softened and bent is directly in contact with the placement platform 23 and can be heated quickly. This leads to unreasonable heat utilization on the one hand, and on the other hand, the middle area of ​​the diaphragm 300 that does not need to be bent is also more prone to scratches, deformation, pitting and other process defects in the subsequent bending and demolding processes after heating and softening. In view of this problem, the present application sets a lifting channel 2202 in the lower mold core 22, so that the placement platform 23 can be lifted and moved along the lifting channel 2202 under the drive of the lifting mechanism 24, so that when the placement platform 23 descends to a predetermined position, the diaphragm can be placed on the plane formed by the placement platform 23 and the bottom wall of the second cavity 2201 for heating. Since the machine heats the lower mold core 22 instead of directly heating the placement platform 23, and there is also a gap between the placement platform 23 and the lower mold core 22, the temperature of the surface of the placement platform 23 will be lower than the bottom wall temperature of the second cavity 2201, so that the heating rate and temperature of the middle area of ​​the diaphragm 300 are lower than those of the areas on both sides of the diaphragm 300, so that the areas on both sides of the diaphragm 300 that need to be bent can be bent after reaching the softening temperature, while the middle area of ​​the diaphragm 300 that does not need to be bent will not reach the softening temperature. This is beneficial for protecting the middle area of ​​the diaphragm 300 and reducing the occurrence of process defects such as scratches, deformations, pitting, etc., and it also rationally utilizes heat, saves energy, and is beneficial for faster cooling of the diaphragm 300 after forming.

[0030] In another embodiment of the present application, the lower mold core 22 is made of graphene material, and the thermal conductivity of the lower mold core 22 is greater than the thermal conductivity of the placement platform 23 .

[0031] Graphene is a high-quality thermal conductive material with a very high thermal conductivity, and is very suitable for preparing thermoforming molds. The lower mold core 22 is made of graphene material, which allows the lower mold core 22 to quickly heat up after being heated by the machine and transfer heat to the two side areas of the diaphragm 300, so that the two side areas of the diaphragm 300 soften. The thermal conductivity of the lower mold core 22 is greater than the thermal conductivity of the placement platform 23, so that the placement platform 23 heats up relatively slowly and at a lower temperature. The middle area of ​​the diaphragm 300 is not easy to heat up and soften, thereby protecting the middle area of ​​the diaphragm 300 and making rational use of heat. Optionally, the placement platform 23 can be made of ordinary steel.

[0032] In another embodiment of the present application, please refer to Figure 2 The upper mold core 11 includes an intermediate block 112 and two heating blocks 113, and the two heating blocks 113 are respectively fixed on both sides of the intermediate block 112. For example, the two heating blocks 113 can be respectively bonded to both sides of the intermediate block 112. The intermediate block 112 and the two heating blocks 113 are fixedly connected as a whole. The two bending portions 111 are respectively and correspondingly located at the bottom of the two heating blocks 113, that is, the bending portions 111 are integrally extended downward from the bottom of the heating blocks 113, and the surfaces of the two bending portions 111 and the bottom surface of the intermediate block 112 form a U-shaped first cavity 1101. The two heating blocks 113 are made of graphene material, which can make the heating blocks 113 quickly heat up after being heated by the machine, and press down and hot-bend the two side areas of the diaphragm 300 during the clamping process of the upper mold core 11 and the lower mold core 22. The thermal conductivity of the heating block 113 is greater than that of the middle block 112, so that the middle block 112 located in the middle of the upper mold core 11 heats up relatively slowly and at a lower temperature, and the middle area of ​​the diaphragm 300 is not easy to heat up and soften, thereby protecting the middle area of ​​the diaphragm 300 and making reasonable use of heat. Optionally, the middle block 112 is made of ordinary steel.

[0033] In another embodiment of the present application, a silicone layer is provided on the top surface of the placement platform 23 and the bottom surface of the middle block 112, respectively, so that during the hot bending process of the upper mold core 11 and the lower mold core 22, the silicone layer can protect the upper and lower surfaces of the middle area of ​​the diaphragm 300 and reduce scratches on the diaphragm 300. In addition, when foreign matter or dust is attached to the surface of the diaphragm 300, pitting may be pressed on the surface of the diaphragm 300 after the upper mold core 11 and the lower mold core 22 are completely closed, and the silicone layer can play a buffering role on the diaphragm 300, and try to prevent foreign matter or dust from pressing pitting on the surface of the diaphragm.

[0034] In another embodiment of the present application, the placement platform 23 is provided with a plurality of negative pressure channels distributed at intervals so that the diaphragm 300 can be adsorbed on the surface of the placement platform 23. Specifically, the negative pressure channel can be a vertical tubular channel that runs through the top and bottom surfaces of the placement platform 23, and the plurality of negative pressure channels are spaced and evenly distributed inside the placement platform 23. When a silicone layer is provided on the surface of the placement platform 23, each negative pressure channel also runs through the silicone layer. The negative pressure channel is connected to an external negative pressure device, so that when the diaphragm 300 is located on the top surface of the placement platform 23, a negative pressure can be formed in the negative pressure channel, thereby adsorbing the diaphragm 300 on the placement platform 23, thereby fixing and positioning the diaphragm 300.

[0035] In another embodiment of the present application, Figure 1 and Figure 2As shown, the lower mold core 22 has two bosses 221, and the two bosses 221 are integrally extended upward from the two side edges of the second cavity 2201. The upper mold core 11 has two grooves 1102 correspondingly, and the grooves 1102 cooperate with the bosses 221. After the upper mold core 11 and the lower mold core 22 are molded, the two bosses 221 enter the two grooves 1102 one by one, so that the upper mold core 11 and the lower mold core 22 are engaged with each other, thereby achieving precise alignment of the upper mold core 11 and the lower mold core 22. In addition, during the process of pressing the upper mold core 11, when the bosses 221 press against the grooves 1102, so that the upper mold core 11 cannot continue to press down, it means that the upper mold core 11 has been pressed down to the predetermined position, thereby playing a role in limiting movement.

[0036] In another embodiment of the present application, the mold includes a heating device 30, and the upper mold core 11 and the lower mold core 22 are respectively connected to the heating device 30, so as to achieve the heating and temperature raising function of the upper mold core 11 and the lower mold core 22. For example, the heating device 30 can be a heating plate, a heating rod or a heating coil.

[0037] In another embodiment of the present application, the heating device 30 includes an upper heating plate 31 and a lower heating plate 32, wherein the upper heating plate 31 is fixedly mounted on the top surface of the upper mold core 11, and the lower heating plate 32 is fixedly mounted on the bottom surface of the lower mold core 22. The upper mold core 11 and the lower mold core 22 are heated and heated by the upper heating plate 31 and the lower heating plate 32 being in contact and heat conduction with the upper mold core 11 and the lower mold core 22 respectively.

[0038] In another embodiment of the present application, the heating device 30 is a plurality of heating rods, and the upper mold core 11 and the lower mold core 22 are each provided with a plurality of heating channels distributed at intervals, and the heating rods are installed in each heating channel one by one. Specifically, the upper mold core 11 and the lower mold core 22 are each provided with a plurality of tubular channels in the horizontal direction, and the tubular channels are distributed as evenly as possible inside the upper mold core 11 and the lower mold core 22, and the heating rods are inserted and installed in each tubular channel of the upper mold core 11 and the lower mold core 22 one by one. In this way, when the heating rods are working, the heat can be transferred to each area of ​​the upper mold core 11 and the lower mold core 22 respectively, thereby achieving heating and temperature rise of the upper and lower mold cores. Compared with respectively setting heating plates on the side surfaces of the upper and lower mold cores, by inserting and installing heating rods in the tubular channels of the upper and lower mold cores, each heating rod can be evenly distributed inside the upper and lower mold cores, thereby heating the upper and lower mold cores in different zones, so that the temperature distribution of the upper mold core 11 and the lower mold core 22 is more uniform.

[0039] In other embodiments, the heating device 30 is a heating coil, and the heating coils can be laid on the top surface of the upper mold core 11 and the bottom surface of the lower mold core 22, respectively. When the heating coils are energized, the upper mold core 11 and the lower mold core 22 can be heated. In addition, the heating coils can also be laid inside the upper mold core 11 and the lower mold core 22. For example, the upper mold core 11 and the lower mold core 22 are provided with a channel for accommodating the heating coil wiring. The heating coils are passed through the wiring channels inside the upper mold core 11 and the lower mold core 22. The heating coils can be coiled or wound around the upper mold core 11 and the lower mold core 22 in a winding manner to be distributed as evenly as possible, thereby making the temperature distribution of the upper mold core 11 and the lower mold core 22 more uniform.

[0040] According to another aspect of the present application, the present application also provides a hot bending forming device, the hot bending forming device comprises the above-mentioned mold, a machine body and a mold clamping manipulator, the machine body is provided with a heating zone and a cooling zone, the mold and the mold clamping manipulator are installed on the machine body. The mold clamping manipulator is used to move the mold between the heating zone and the cooling zone.

[0041] During the operation of the hot bending forming equipment, the upper mold 10 and the lower mold 20 of the mold need to be opened first, and the machine body controls the lifting mechanism 24 to lower the placement platform 23 to a predetermined position, and then the diaphragm 300 to be formed is placed on the placement platform 23 of the mold. The heating system of the machine body is started to heat the heating device 30, and the heating device 30 conducts heat to the upper mold core 11 and the lower mold core 22, thereby heating and softening the diaphragm 300. Then the machine body controls the lifting mechanism 24 to raise the placement platform 23 to a predetermined position, and then the machine body controls the upper mold core 11 to gradually press down and close the mold with the lower mold core 22, so as to perform hot bending forming on the diaphragm 300. After forming, the clamping manipulator moves the mold from the heating area to the cooling area, and starts the cooling system of the machine body to cool the mold, and the diaphragm 300 in the mold is cooled and formed. When the temperature of the mold drops to a predetermined value, the mold is opened and the film is taken out, and the mold clamping robot moves the mold back to the heating zone for the next hot bending forming.

[0042] It is worth mentioning that in the prior art, after the diaphragm is 3D-formed by high-pressure vacuum suction molding, it is necessary to process the diaphragm through a CNC machine tool to cut off the excess scraps at the edge of the diaphragm, and finally cut the material. The CNC machining process has requirements for the spacing of the product layout on the PC+PMMA composite sheet, and the spacing between adjacent products needs to be designed to be larger, otherwise interference will occur during the machining operation. If the hot bending molding equipment provided by the present application is used to perform 3D molding on the diaphragm 300, the diaphragm 300 is first CNC-processed to cut off the scraps before the diaphragm 300 is hot-bent; in this way, during the CNC machining process of the diaphragm, the spacing of the product layout on the PC+PMMA composite sheet only needs to be able to accommodate the width of the CNC tool, so the use of the hot bending molding equipment of the present application saves more material costs for product layout.

[0043] The mold for hot bending and forming of IML diaphragms and the hot bending and forming equipment including the mold provided in the present application perform 3D forming of IML diaphragms by hot bending and forming. During the bending and forming process, the pattern or text at the edge of the diaphragm will not be pulled and deformed, which solves the process pain point of pulling and deforming the edge of the diaphragm in the prior art and greatly improves the product yield. Second, in the process of heating and softening the diaphragm 300, the heating rate and temperature of the middle area of ​​the diaphragm 300 are lower than those of the two side areas of the diaphragm, so that the areas on both sides of the diaphragm 300 that need to be bent can be bent after reaching the softening temperature, while the middle area of ​​the diaphragm 300 that does not need to be bent will not reach the softening temperature, which is beneficial to protecting the middle area of ​​the diaphragm 300, reducing the occurrence of process defects such as scratches, deformation, pitting, etc., and reasonably utilizing heat, saving energy, and facilitating faster cooling and cooling of the diaphragm 300 after forming. Third, the use of the mold and hot bending and forming equipment can further effectively utilize the product imposition, greatly saving material costs and facilitating mass production.

[0044] The above description is only a preferred embodiment of the present application and is not intended to limit the present application. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present application should be included in the protection scope of the present application.

Claims

1. A mold for hot bending of IML membrane, characterized in that: The mold comprises: An upper mold, the upper mold comprising an upper mold core, the bottom surface of the upper mold core is provided with two bending portions protruding downward and spaced apart, so as to form a U-shaped first cavity between the two bending portions; A lower mold, the lower mold comprising a base, a lower mold core, a placement platform and a lifting mechanism, the lower mold core and the lifting mechanism are both installed on the base, the lower mold core has a second cavity opening upward, a lifting channel is provided between the bottom wall of the second cavity and the bottom surface of the lower mold core, the placement platform is used to place the diaphragm and is located in the lifting channel; The lifting mechanism drives the placement platform to rise so that the top surface of the placement platform is higher than the bottom wall of the second cavity, and a third cavity is formed between the placement platform and the inner walls on both sides of the cavity, the placement platform matches the shape of the first cavity, and the bending portion matches the shape of the third cavity; or, the lifting mechanism drives the placement platform to descend so that the top surface of the placement platform and the bottom wall of the cavity are located in the same plane.

2. The mold according to claim 1, characterized in that The lower mold core is made of graphene material, and the thermal conductivity of the lower mold core is greater than the thermal conductivity of the placement platform.

3. The mold according to claim 2, characterized in that The upper mold core includes a middle block and two heating blocks, the two heating blocks are respectively fixed on both sides of the middle block, and the two bending parts are respectively located at the bottom of the two heating blocks; the two heating blocks are made of graphene material, and the thermal conductivity of the heating blocks is greater than the thermal conductivity of the middle block.

4. The mold according to claim 3, characterized in that The top surface of the placement platform and the bottom surface of the middle block are respectively provided with a silica gel layer.

5. The mold according to claim 3, characterized in that: The placement platform is provided with a plurality of negative pressure channels distributed at intervals, so that the diaphragm can be adsorbed on the surface of the placement platform.

6. The mold according to any one of claims 1 to 5, characterized in that: The lower die core has two bosses, which are integrally extended upward from the two side edges of the second cavity; the upper die core has two grooves correspondingly, which cooperate with the bosses.

7. The mold according to any one of claims 1 to 5, characterized in that: The mold comprises a heating device, and the upper mold core and the lower mold core are respectively connected to the heating device.

8. The mold according to claim 7, characterized in that The heating device comprises an upper heating plate and a lower heating plate, wherein the upper heating plate is fixedly mounted on the top surface of the upper mold core, and the lower heating plate is fixedly mounted on the bottom surface of the lower mold core.

9. The mold according to claim 7, characterized in that: The heating device is a plurality of heating rods. The upper mold core and the lower mold core are both provided with a plurality of heating channels distributed at intervals. The heating rods are installed in each of the heating channels in a one-to-one correspondence.

10. A hot bending forming device, characterized in that: The hot bending forming equipment includes a mold, a machine body and a mold clamping robot as described in any one of claims 1 to 9, the machine body is provided with a heating zone and a cooling zone, the mold and the mold clamping robot are installed on the machine body, and the mold clamping robot is used to move the mold between the heating zone and the cooling zone.

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