Forming and connecting device for plastic imitating metal mobile phone backplane, forming and connecting structure and manufacturing method thereof

Abstract

The present disclosure provides a forming and connecting device for a plastic imitating a metal mobile phone backplane, a forming and connecting structure thereof, and a manufacturing method therefor. The forming and connecting device for the plastic imitating a metal mobile phone backplane includes a plurality of inserts, an upper mold core, and a lower mold core. The plurality of inserts are sequentially spliced along the circumferential direction of the lower mold core and form a cavity with the lower mold core and the upper mold core. A snap forming groove and a housing groove communicating with each other are formed in the cavity. The lower mold core is provided with a compensation glue groove communicating with the snap forming groove for reducing the shrinkage deformation of the plastic. The upper mold core is provided with a first annular inclined groove for forming a bright parting inclined surface, and the lower mold core is provided with a second annular inclined groove for forming a bright parting inclined surface. A compensation glue layer is formed in the compensation glue groove to reduce the height difference generated on the surface between the aluminum sheet and the plastic housing of the mobile phone backplane. A bright parting inclined surface with a brightness difference from the adjacent parting surface is formed in the first annular inclined groove and the second annular inclined groove, so that the bright edge effect of the bright parting inclined surface is better.

Description

Technical Field

[0001] The present disclosure relates to the technical field of mobile phone backplane manufacturing, and particularly to a forming and connecting device, a forming and connecting structure and a manufacturing method thereof for a plastic imitating metal mobile phone backplane. Background Art

[0002] The design of modern smart phones is developing towards a delicate and high-end metal appearance. However, the manufacturing process of metal shells is complex and their cost is relatively high. In order to reduce costs and obtain the texture of a metal shell, a plastic shell is made by injection molding. After spraying and electroplating a metal paint on the plastic shell, an aluminum sheet is then compounded and connected to the plastic shell to obtain a lightweight imitating metal mobile phone backplane.

[0003] The plastic shell is formed with a snap connection part for connecting with the aluminum sheet. The thickness of the snap connection part is relatively thick. During the cooling and forming process of the injection-molded plastic shell, the thicker part has a larger shrinkage amount during the cooling process, making the plastic shell prone to deformation. The surface of the plastic shell and the surface of the installed aluminum sheet are uneven, resulting in a height difference between the surface of the aluminum sheet and the plastic shell. When the injection-molded plastic shell is processed by EDM to cut a parting surface with edges, due to the natural R angle generated by ablation cutting, the bright edge of the plastic shell cut cannot achieve the effect of a metal bright edge, thus affecting the imitating metal effect of the plastic of the mobile phone backplane.

[0004] For example, a new type of metal mobile phone back cover disclosed in the comparative document CN201620086845.1 includes a body, which has a backplane, an upper back frame and a lower back frame. The backplane is an aluminum backplane; both the upper back frame and the lower back frame are plastic frames. An upper fitting plate that fits with the inner surface of the upper part of the backplane is integrally formed on the upper back frame, and a lower fitting plate that fits with the inner surface of the lower part of the backplane is integrally formed on the lower back frame. The upper fitting plate and the backplane are bonded and pressed together with glue, and the lower fitting plate and the backplane are bonded and pressed together with glue. However, this solution cannot solve the problem of the height difference generated after injection molding shrinkage between the surface of the aluminum sheet and the plastic shell, and its upper back frame and lower back frame do not have the imitating metal effect and the bright edge effect.

[0005] Another example is a mobile phone backplane color effect disclosed in the comparative document CN202111512321.6, which includes the following steps: selecting a composite board; spraying color ink to form a spray coating; placing it in an electrolyte solution for electroplating to form an electroplated layer on the spray coating; printing a layer of transparent ink layer on the electroplated layer; and coating a strengthening layer on the other side of the composite board. This solution can keep the spray coating with a metallic luster and obtain a better aurora color effect by electroplating after the spray coating, but this solution fails to solve the problem of the height difference generated between the surface of the aluminum sheet and the plastic shell during injection molding after the aluminum sheet and the plastic shell are compounded and connected, and at the same time, the mobile phone backplane cannot achieve the effect of a metal bright edge. Summary of the Invention

[0006] The purpose of the present invention is to overcome the shortcomings of the prior art and to provide a molding connection device, a molding connection structure and a manufacturing method thereof for connecting aluminum sheets and plastics, reducing the height difference between the surfaces of the aluminum sheets and the plastic shells and achieving a better imitation metal highlight edge effect for imitating metal mobile phone back panel plastics.

[0007] The purpose of this disclosure is achieved through the following technical solutions:

[0008] A molding and connecting device for plastic of a metal-like mobile phone back panel, comprising an insert, an upper mold core and a lower mold core, wherein the lower mold core is provided with a plurality of mounting grooves in the circumference thereof, the number of the inserts is multiple, each of the inserts is installed in the corresponding mounting groove, the multiple inserts are sequentially spliced ​​along the circumference of the lower mold core, the multiple inserts and the lower mold core jointly form a cavity, the upper mold core is covered in the cavity, an injection molding flow channel is provided in the upper mold core, a connected buckle molding groove and a shell groove are formed in the cavity, the shell groove is used to mold the main body of the plastic shell of the mobile phone back panel, the buckle molding groove is used to mold a buckle connection part connected to an aluminum sheet, the injection molding flow channel is connected to the shell groove, the lower mold core is provided with a compensating rubber groove connected to the buckle molding groove, and the compensating rubber groove is used to reduce the deformation caused by plastic shrinkage;

[0009] The upper mold core is provided with a first annular bevel groove connected to the mold cavity along the circumference of the mold cavity, and the lower mold core is provided with a second annular bevel groove connected to the mold cavity along the circumference of the mold cavity. The first annular bevel groove and the second annular bevel groove are used to form two highlighted parting slopes on the upper and lower edges of the plastic shell of the back panel of the mobile phone.

[0010] In one embodiment, the insert includes an integrally formed raised portion and a movable portion, the raised portion of each insert abuts in sequence along the circumference of the cavity, the raised portion of each insert is adjacent to the cavity, each movable portion is installed in the installation groove, and the movable portion is also provided with a protruding limit block, and a plurality of limit grooves are opened in the circumference of the lower mold core, and each limit block is embedded in the corresponding limit groove.

[0011] In one of the embodiments, an assembly groove for demoulding is formed at one end of the movable portion away from the protruding portion.

[0012] In one embodiment, a first guide slope is provided on a side of the protruding portion adjacent to the upper die core, and a first abutting portion is convexly provided on the upper die core, and the first abutting portion is attached to the first guide slope; and / or,

[0013] A second guide slope is arranged on one side of the protruding portion adjacent to the lower die core, and a second abutting portion is convexly arranged on the lower die core, and the second abutting portion is attached to the second guide slope.

[0014] In one embodiment, the thickness difference between the snap forming groove and the housing groove is 0.2 mm - 0.7 mm, and the groove depth of the compensation glue groove is 0.001 mm - 0.005 mm.

[0015] In one embodiment, a first heating channel is provided in the upper mold core, a second heating channel is provided in the insert, and a third heating channel is provided in the lower mold core. The first heating channel, the second heating channel, and the third heating channel are respectively used to communicate with corresponding heating devices, so that the temperature range of the insert is 100°C - 120°C, the temperature range of the upper mold core is 70°C - 85°C, and the temperature range of the lower mold core is 70°C - 85°C.

[0016] In one embodiment, the forming and connecting device for the plastic of the metal-like mobile phone back plate further includes a plurality of lifters. The upper mold core is provided with ejection channels, the ejection channels are arranged at intervals along the circumference of the cavity, and each lifter is installed in the corresponding ejection channel. The ejection channels are inclined towards the center of the cavity.

[0017] In one embodiment, the compensation glue groove has an arc transition curved surface structure.

[0018] A forming and connecting structure for the plastic of the metal-like mobile phone back plate includes a mobile phone back plate plastic housing and an aluminum sheet obtained by injecting the forming and connecting device for the plastic of the metal-like mobile phone back plate in any of the above embodiments. The upper and lower edges of the mobile phone back plate plastic housing are respectively formed with parting inclined surfaces. A receiving groove is provided in the mobile phone back plate plastic housing. The aluminum sheet is installed in the receiving groove. The aluminum sheet is convexly provided with snap protrusions. A snap connection part is provided on one side of the mobile phone back plate plastic housing. A snap groove is provided in the snap connection part. The snap protrusions are installed in the snap groove. A compensation glue layer is provided on the surface of the snap connection part, and the surface of the compensation glue layer is flush with the surface of the aluminum sheet.

[0019] A manufacturing method of a forming and connecting structure for the plastic of the metal-like mobile phone back plate is manufactured by using the forming and connecting device for the plastic of the metal-like mobile phone back plate in any of the above embodiments.

[0020] Install a plurality of the inserts on the lower mold core in sequence, and cover the upper mold core on the cavity to close the mold;

[0021] Heat up the insert, the upper mold core, and the lower mold core through a heating device, so that the temperature range of the insert is 100°C - 120°C, the temperature range of the upper mold core is 70°C - 85°C, and the temperature range of the lower mold core is 70°C - 85°C;

[0022] Inject the injection plastic into the injection runner for injection molding;

[0023] Cool the cavity, and after mold opening, obtain a plastic mobile phone backplate housing with two highlighted parting inclined planes formed at the upper and lower edges.

[0024] Paint and electroplate each parting surface on the surface of the plastic mobile phone backplate housing so that the upper and lower edges of the plastic mobile phone backplate housing form highlighted parting inclined planes with a highlighted edge effect, and obtain a plastic mobile phone backplate housing with a metallic texture.

[0025] Connect the aluminum sheet to the plastic mobile phone backplate housing to obtain a formed connection structure for the plastic mobile phone backplate imitating metal.

[0026] Compared with the prior art, the present disclosure has at least the following advantages:

[0027] For the above-mentioned formed connection device for the plastic mobile phone backplate imitating metal, multiple inserts are spliced and then form a cavity with the upper mold core and the lower mold core. The upper mold core, the lower mold core and multiple inserts are separately and precisely processed, so that the plastic mobile phone backplate housing obtains the effect of more parting surfaces; the thickness of the snap connection part of the plastic mobile phone backplate housing is relatively thick. After cooling, the snap connection part generates internal shrinkage and a thickness difference is generated on the surface of the aluminum sheet. The formed compensation glue layer in the compensation glue groove is kept flat with the surface of the aluminum sheet after molding, reducing the height difference generated on the surface between the aluminum sheet and the plastic mobile phone backplate housing; two inclined parting inclined planes are formed in the first annular groove and the second annular groove of the plastic mobile phone backplate housing, so that the surface of the inclined parting inclined plane is flat, and the boundary between the parting inclined plane and the adjacent parting surface is obvious; the formed parting inclined plane of the plastic mobile phone backplate housing is more likely to generate parallax relative to the plane, making the incident light easier to reflect, thereby covering up the tiny defects generated during the injection molding process of the parting inclined plane, and further making it easier to generate a brightness difference between the inclined parting inclined plane and the plane of the adjacent parting surface, and the highlighted edge effect formed by the parting inclined plane of the plastic mobile phone backplate housing is better.

[0028] A manufacturing method for a formed connection structure of a plastic mobile phone backplate imitating metal. Through the coordination of multiple processes, successively and precisely injection mold the plastic mobile phone backplate housing, paint and electroplate each parting surface of the plastic mobile phone backplate housing, so that the upper and lower edges of the plastic mobile phone backplate housing form highlighted parting inclined planes, and then compound and connect the plastic mobile phone backplate housing with the aluminum sheet, so that the obtained formed connection structure of the plastic mobile phone backplate imitating metal has the effects of lightweight structure, high strength and highlighted edge metallic texture. Description of the Drawings

[0029] To more clearly illustrate the technical solutions of the embodiments of the present disclosure, the following will briefly introduce the accompanying drawings required for the embodiments. It should be understood that the following drawings only show some embodiments of the present disclosure, and thus should not be regarded as limiting the scope. For those of ordinary skill in the art, without creative efforts, other related drawings can also be obtained based on these drawings.

[0030] Figure 1 Structural schematic diagram of a plastic forming and connecting device for a metal-like mobile phone back panel in an embodiment;

[0031] Figure 2 For Figure 1 Exploded view of the plastic forming and connecting device for the metal-like mobile phone back panel shown;

[0032] Figure 3 For Figure 1 Partial structural schematic diagram of the plastic forming and connecting device for the metal-like mobile phone back panel shown;

[0033] Figure 4 For Figure 1 Cross-sectional view of the plastic forming and connecting device for the metal-like mobile phone back panel shown;

[0034] Figure 5 For Figure 4 Partial enlarged view at A of the plastic forming and connecting device for the metal-like mobile phone back panel shown;

[0035] Figure 6 For Figure 1 Structural schematic diagram of the upper mold core shown;

[0036] Figure 7 For Figure 1 Structural schematic diagram of the lower mold core shown;

[0037] Figure 8 Structural schematic diagram of a plastic forming and connecting structure for a metal-like mobile phone back panel in an embodiment;

[0038] Figure 9 For Figure 8 Another structural schematic diagram of the plastic forming and connecting structure for the metal-like mobile phone back panel shown;

[0039] Figure 10 For Figure 8 Another structural schematic diagram of the plastic forming and connecting structure for the metal-like mobile phone back panel shown;

[0040] Figure 11 Flowchart of the steps of a manufacturing method of a plastic forming and connecting structure for a metal-like mobile phone back panel in an embodiment. Detailed implementation manners

[0041] To facilitate the understanding of the present disclosure, the present disclosure will be described more comprehensively below with reference to the relevant drawings. Preferred embodiments of the present disclosure are shown in the drawings. However, the present disclosure can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, these embodiments are provided to make the disclosure of the present disclosure more thorough and comprehensive.

[0042] It should be noted that when an element is referred to as being "fixed to" another element, it can be directly on the other element or there can also be an intermediate element. When an element is considered to be "connected" to another element, it can be directly connected to the other element or there may be an intermediate element at the same time. The terms "vertical", "horizontal", "left", "right" and similar expressions used herein are for illustrative purposes only and do not represent the only embodiments.

[0043] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those of ordinary skill in the technical field to which the present disclosure belongs. The terms used herein in the specification of the present disclosure are only for the purpose of describing specific embodiments and are not intended to limit the present disclosure. The term "and / or" used herein includes any and all combinations of one or more of the related listed items.

[0044] To better understand the technical solutions and beneficial effects of the present disclosure, the present disclosure will be further described in detail below with specific embodiments:

[0045] Please refer to Figures 1 to 5 , which is a molding connection device 10 for a plastic imitation metal mobile phone back panel according to an embodiment of the present invention, including an insert 100, an upper mold core 200 and a lower mold core 300. A plurality of mounting grooves 301 are formed in the circumferential direction of the lower mold core 300. The number of the inserts 100 is multiple, and each insert 100 is installed in a corresponding mounting groove 301. The plurality of inserts 100 are sequentially spliced along the circumferential direction of the lower mold core 300. The plurality of inserts 100 and the lower mold core 300 together form a cavity 101. The upper mold core 200 covers the cavity 101. An injection runner 201 is formed in the upper mold core 200, and the injection runner 201 communicates with the cavity 101. A snap forming groove 102 and a housing groove 103 that are connected to each other are formed in the cavity 101. The housing groove 103 is used to form the main body of the plastic housing 20 of the mobile phone back panel. The snap forming groove 102 is used to form a snap connection portion 20a connected to the aluminum sheet 30. The injection runner 201 communicates with the housing groove 103. The lower mold core 300 is provided with a compensation glue groove 302 that communicates with the snap forming groove 102. The compensation glue groove 302 is used to reduce the deformation caused by plastic shrinkage;

[0046] The upper mold core 200 is provided with a first annular inclined groove 202 along the circumferential edge of the cavity 101, and the lower mold core 300 is provided with a second annular inclined groove 303 along the circumferential edge of the cavity 101. The first annular inclined groove 202 communicates with the cavity 101. The first annular inclined groove 202 and the second annular inclined groove 303 are used to form two bright parting inclined surfaces 211a at the upper and lower edges of the plastic shell 20 of the mobile phone backplane.

[0047] In this embodiment, after a plurality of inserts 100 are spliced, they form a cavity 101 with the upper mold core 200 and the lower mold core 300. The plastic shell 20 of the mobile phone backplane is injection-molded in the cavity 101. The plastic shell 20 of the mobile phone backplane is used to form a molded connection structure of a metal-like plastic for the mobile phone backplane in connection with the aluminum sheet 30. When demolding during the injection molding process of the plastic shell 20 of the mobile phone backplane, the lower mold core 300, the plurality of inserts 100, and the lower mold core 300 are sequentially separated to demold the plastic shell 20 of the mobile phone backplane. When the plastic shell 20 of the mobile phone backplane is demolded, the lower mold core 300, the plurality of inserts 100, and the lower mold core 300 can be sequentially separated for peeling, reducing the peeling strength between the plastic shell 20 of the mobile phone backplane and the mold, thereby reducing the deformation of the plastic shell 20 of the mobile phone backplane. It can be understood that the part of the buckle connection part 20a of the plastic shell 20 of the mobile phone backplane is thicker, and internal shrinkage occurs after the buckle connection part 20a cools, resulting in a thickness difference between the surface of the buckle connection part 20a and the aluminum sheet 30. After the molded compensation glue layer in the compensation glue groove 302 shrinks, the surfaces of the plastic shell 20 of the mobile phone backplane and the aluminum sheet 30 are kept flat. The plastic forms an inclined bright parting inclined surface 211a in the first annular inclined groove 202, preventing the natural R angle generated by direct ablation, making the surface of the inclined bright parting inclined surface 211a flatter. The incident angle of the incident light on the inclined bright parting inclined surface 211a is different from that on the plane, making it easier to meet the conditions for specular reflection. The inclined bright parting inclined surface 211a is prone to parallax relative to the plane, making the incident light easier to reflect, thereby covering up the tiny flaws generated during the injection molding process on the inclined bright parting inclined surface 211a, and making it easier to generate a brightness difference between the inclined bright parting inclined surface 211a and the side plane.

[0048] The above-mentioned plastic forming and connecting device 10 for the metal-like mobile phone back panel. After multiple inserts 100 are spliced, a cavity 101 is formed with the upper mold core 200 and the lower mold core 300. The upper mold core 200, the lower mold core 300 and multiple inserts 100 are separately precision machined, so that the plastic shell 20 of the mobile phone back panel obtains the effect of more parting surfaces; the thickness of the snap connection part 20a of the plastic shell 20 of the mobile phone back panel is relatively thick. After the snap connection part 20a cools, internal shrinkage occurs, resulting in a thickness difference with the surface of the aluminum sheet 30. The formed compensation glue layer in the compensation glue groove 302 remains flat with the surface of the aluminum sheet 30 after molding, reducing the height difference generated on the surface between the aluminum sheet 30 and the plastic shell 20 of the mobile phone back panel; two inclined bright parting surfaces 211a are formed in the first annular inclined groove 202 and the second annular inclined groove 303 of the plastic shell 20 of the mobile phone back panel, so that the surface of the inclined bright parting surface 211a is flat, and the boundary between the bright parting surface 211a and the adjacent parting surface is obvious; the bright parting surface 211a formed on the plastic shell 20 of the mobile phone back panel is prone to parallax relative to the plane, making the incident light easier to reflect, thereby covering up the tiny defects generated during the injection molding process of the bright parting surface 211a. Furthermore, it is easier to generate a brightness difference between the inclined bright parting surface 211a and the plane of the adjacent parting surface, and the bright edge effect formed by the bright parting surface 211a of the plastic shell 20 of the mobile phone back panel is better.

[0049] It can be understood that the thickness of the plastic shell 20 of the mobile phone back panel is relatively thin, and the precision and fit requirements of the plastic forming and connecting device 10 for the metal-like mobile phone back panel are relatively high. It is necessary to precisely machine the plastic forming and connecting device 10 for the metal-like mobile phone back panel. Through the splicing and cooperation of multiple inserts 100, the upper mold core 200 and the lower mold core 300, the fit between the various components in the plastic forming and connecting device 10 for the metal-like mobile phone back panel is tight and accurate, so that the plastic shell 20 of the mobile phone back panel obtains the effect of more parting surfaces; the first annular inclined groove 202 and the second annular inclined groove 303 need to form a bright parting surface 211a with a bright edge, and it is necessary to perform high-polishing treatment on the first annular inclined groove 202 and the second annular inclined groove 303 to make the surface of the bright parting surface 211a formed on the plastic shell 20 of the mobile phone back panel flat.

[0050] Such as Figure 2As shown, in one of the embodiments, the insert 100 includes an integrally formed raised portion 110 and a movable portion 120. The raised portions 110 of each insert 100 are sequentially abutted along the circumferential direction of the cavity 101. Each raised portion 110 of the insert 100 is adjacent to the cavity 101. Each movable portion 120 is installed in the installation groove 301. The movable portion 120 further protrudes with a limiting block 121. A plurality of limiting grooves 304 are formed in the circumferential direction of the lower die core 300. Each limiting block 121 is embedded in the corresponding limiting groove 304. In this embodiment, the raised portions 110 of each insert 100 are sequentially abutted along the circumferential direction of the cavity 101, so that the inserts 100 can be closely fitted to form a continuous structure surrounding the cavity 101. The movable portion 120 is installed in the installation groove 301, and the limiting block 121 limits the position where the movable portion 120 is installed on the lower die core 300, so that the position where the insert 100 is installed on the lower die core 300 is accurate, which facilitates the disassembly and replacement of the insert 100, and makes the cooperation between the insert 100, the upper die core 200 and the lower die core 300 closer.

[0051] As Figure 2 shown, in one of the embodiments, an assembly groove 1201 for draft drawing is formed at one end of the movable portion 120 away from the raised portion 110. In this embodiment, when the mobile phone backplane plastic shell 20 in the cavity 101 is cooled and solidified, due to the adhesion force between the plastic and the surface of the raised portion 110, the raised portion 110 adheres to the mobile phone backplane plastic shell 20 in the cavity 101. By pulling the assembly groove 1201, the raised portion 110 can be separated from the upper die core 200.

[0052] As Figure 4As shown, in one of the embodiments, a first guiding inclined surface 1101 is provided on one side of the protruding portion 110 adjacent to the upper mold core 200. The upper mold core 200 is convexly provided with a first abutting portion 210, and the first abutting portion 210 is attached to the first guiding inclined surface 1101. A second guiding inclined surface 1102 is provided on one side of the protruding portion 110 adjacent to the lower mold core 300. The lower mold core 300 is convexly provided with a second abutting portion 310, and the second abutting portion 310 is attached to the second guiding inclined surface 1102. In this embodiment, the cooperation between the first guiding inclined surface 1101 and the first abutting portion 210, and the cooperation between the second guiding inclined surface 1102 and the second abutting portion 310 enable the precise alignment and positioning among the upper mold core 200, the lower mold core 300 and the insert 100 during the injection molding process, reducing the deviation and deformation of the mobile phone backplane plastic housing 20 in the injection molding cavity 101. After the mobile phone backplane plastic housing 20 in the cavity 101 is cooled and solidified, it can slide along the respective first guiding inclined surface 1101 and the second guiding inclined surface 1102 through the first abutting portion 210 and the second abutting portion 310, enabling the smooth separation of the protruding portion 110 from the mobile phone backplane plastic housing 20 in the cavity 101. The first guiding inclined surface 1101 and the second guiding inclined surface 1102 also reduce the wear between the insert 100 and the upper mold core 200 and the lower mold core 300, thereby extending the service life of the forming and connecting device 10 for the imitation metal mobile phone backplane plastic.

[0053] As Figure 4 , Figure 7 and Figure 8As shown, in one embodiment, a first heating channel 203 is provided in the upper mold core 200, a second heating channel 104 is provided in the insert 100, and a third heating channel 305 is provided in the lower mold core 300. The first heating channel, the second heating channel, and the third heating channel are respectively used to communicate with corresponding heating devices, so that the temperature range of the insert is 100°C - 120°C, the temperature range of the upper mold core is 70°C - 85°C, and the temperature range of the lower mold core is 70°C - 85°C. In this embodiment, the upper mold core 200, the lower mold core 300, and the insert 100 can be separately heated through the second heating channel 104, the third heating channel 305, and the first heating channel 203, so that the temperature control of different positions in the cavity 101 is more accurate, and the heating temperature can be flexibly adjusted according to the requirements of different parts. Thus, different temperature settings are allowed in the cavity 101 to cope with the thickness differences of different parts of the housing and optimize the cooling rate. The temperature of the molten injection molding material is relatively high. The first annular inclined groove 202 of the upper mold core 200 and the second annular inclined groove 303 of the lower mold core 300 are in contact with the molten injection molding material. The temperature difference between the molten injection molding material and the insert 100 is relatively small, while the temperature difference between the molten injection molding material and the upper mold core 200 and the lower mold core 300 is relatively large. This enables the injection molding material to rapidly cool below the glass transition temperature Tg of PC polycarbonate within 0.2 s - 0.5 s, freezing the surface molecular chains of the inclined bright parting slope 211a formed by the injection molding material, reducing the movement and rearrangement of the molecular chains during the cooling process, and thus making the bright parting slope 211a formed by the injection molding material have a higher gloss. By passing cooling gas or cooling liquid through the second heating channel 104, the third heating channel 305, and the first heating channel 203, the plastic housing 20 of the mobile phone backplane in the cavity 101 can be rapidly cured and formed, accelerating the injection molding production process.

[0054] As Figures 5 to 7As shown, further, the upper mold core 200 includes an upper mold core 220 and an upper mold frame 230. The upper mold frame 230 is penetrated with a first installation channel 2301. The upper mold core 220 is installed in the first installation channel 2301. The first heating channel 203 is arranged circumferentially along the first installation channel 2301 in the upper mold frame 230. The upper mold core 220 is used to contact the inner wall of the upper part of the mobile phone back plastic shell 20. A first annular inclined groove 202 is formed between the upper mold core 220 and the upper mold frame 230. The upper mold frame 230 is used to contact the outer wall of the high-brightness parting inclined surface 211a of the upper part of the mobile phone back plastic shell 20; and / or, the lower mold core 300 includes a lower mold core 320 and a lower mold frame 330. The lower mold frame 330 is penetrated with a second installation channel 3301. The lower mold core 320 is installed in the second installation channel 3301. The third heating channel 305 is arranged circumferentially along the second installation channel 3301 in the lower mold frame 330. The lower mold core 320 is used to contact the inner wall of the lower part of the mobile phone back plastic shell 20. A second annular inclined groove 303 is formed between the lower mold core 320 and the lower mold frame 330. The lower mold frame 330 is used to contact the outer wall of the high-brightness parting inclined surface 211a of the lower part of the mobile phone back plastic shell 20. In this embodiment, the upper mold core 220 and the lower mold core 320 are made of high thermal conductivity materials such as beryllium copper alloy or tungsten copper alloy to ensure rapid heat transfer. The upper mold frame 230 surrounds the upper mold core 220, and the lower mold frame 330 surrounds the lower mold core 320, so that the temperature of the upper mold core 220 and the lower mold core 320 is heated more evenly and stably. The contact surfaces of the upper mold core 220 and the lower mold core 320 with the mobile phone back plastic shell 20 in the cavity 101 are larger, so that the shrinkage of the mobile phone back plastic shell 20 is smaller.

[0055] It can be understood that a first annular inclined groove 202 is formed between the upper mold core 220 and the upper mold frame 230. The upper mold frame 230 is used to contact the outer wall of the high-brightness parting inclined surface 211a of the upper part of the mobile phone back plastic shell 20, so as to form the high-brightness parting inclined surface 211a of the mobile phone back plastic shell 20 in the first annular inclined groove 202. By controlling the temperature difference between the upper mold frame 230 and the injection plastic through the first heating channel 203, a smoother high-brightness parting inclined surface 211a of the mobile phone back plastic shell 20 is formed after the injection plastic contacts the upper mold frame 230; a second annular inclined groove 303 is formed between the lower mold core 320 and the lower mold frame 330. The lower mold frame 330 is used to contact the outer wall of the high-brightness parting inclined surface 211a of the lower part of the mobile phone back plastic shell 20, so as to form the high-brightness parting inclined surface 211a of the mobile phone back plastic shell 20 in the second annular inclined groove 303. By controlling the temperature difference between the lower mold frame 330 and the injection plastic through the third heating channel 305, a smoother high-brightness parting inclined surface 211a of the mobile phone back plastic shell 20 is formed after the injection plastic contacts the lower mold frame 330.

[0056] In one embodiment, the thickness difference between the snap forming groove 102 and the housing groove 103 is 0.2 mm - 0.7 mm, and the groove depth of the compensation glue groove 302 is 0.001 mm - 0.005 mm. In this embodiment, after the plastic material is injection molded and taken out of the cavity 101 and cooled to room temperature, the snap forming groove 102 in the cavity 101 is the thicker part of the housing, and the snap connection part 20a formed by the snap forming groove 102 shrinks during the injection molding process; specifically, when the injection molding material is PC polycarbonate, the thickness of the snap forming groove 102 is 1 mm - 1.3 mm, the thickness of the housing groove 103 is 0.6 mm - 0.8 mm, and the shrinkage rate of PC polycarbonate after molding is about 0.5% - 0.7%, so that the snap connection part 20a shrinks by 0.001 mm - 0.005 mm. The compensation glue groove 302 compensates for the height difference between the snap connection part 20a and the aluminum sheet 30, so that the surface of the plastic housing 20 of the mobile phone back plate and the combined aluminum sheet 30 maintain a smooth transition effect.

[0057] As Figure 1 and Figure 4 shown, in one embodiment, the forming and connecting device 10 of the imitation metal mobile phone back plate plastic further includes a plurality of lifters 400. The upper mold core 200 is provided with ejection channels 204. The ejection channels 204 are arranged at intervals along the circumference of the cavity 101. Each lifter 400 is installed in the corresponding ejection channel 204, and the ejection channel 204 is inclined towards the center of the cavity 101. In this embodiment, the lifter 400 slides in the ejection channel 204, thereby driving the separation of the plastic housing 20 of the mobile phone back plate from the upper mold core 200. The ejection channel 204 is inclined towards the center of the cavity 101, so that during the ejection process, the ejection force can be more evenly distributed on the plastic housing 20 of the mobile phone back plate, reducing the risk of excessive local stress causing deformation or damage, and avoiding the situation of jamming during the production process of the forming and connecting device 10 of the imitation metal mobile phone back plate plastic, thereby improving the production efficiency.

[0058] As Figure 3 shown, in one embodiment, the compensation glue groove 302 has an arc transition curved surface structure. In this embodiment, the transition surface between the compensation glue layer and the surface of the plastic housing 20 of the mobile phone back plate is smooth, making the surface of the plastic housing 20 of the mobile phone back plate transition smoothly; the inside of the compensation glue groove 302 is a smooth curved surface, reducing the stress concentration of the lower mold core 300, improving the fatigue resistance of the lower mold core 300, and at the same time reducing the stress concentration caused by the flow and cooling shrinkage of the injection molding material, improving the fatigue resistance of the compensation glue layer.

[0059] In one embodiment, the upper mold core 200 is convexly provided with positioning protrusions, and the lower mold core 300 is provided with positioning grooves, and the positioning protrusions are embedded in the positioning grooves. In this embodiment, when the upper mold core 200 and the lower mold core 300 are closed, the positioning protrusions of the upper mold core 200 will accurately embed into the positioning grooves of the lower mold core 300, so as to ensure the accurate relative position between the upper mold core 200 and the lower mold core 300. Through the cooperation of the positioning protrusions and the positioning grooves, the closing operation of the upper mold core 200 and the lower mold core 300 is facilitated, and the precision of the plastic forming and connecting device 10 for the imitation metal mobile phone backplane when it is closed is improved.

[0060] As Figures 8 to 10 shown, the present application also provides a plastic forming and connecting structure for an imitation metal mobile phone backplane. The plastic forming and connecting structure for the imitation metal mobile phone backplane includes a mobile phone backplane plastic housing 20 and an aluminum sheet 30 obtained by injecting plastic into the plastic forming and connecting device 10 for the imitation metal mobile phone backplane described in any of the above embodiments. Highlight parting inclined surfaces 211a are respectively formed at the upper and lower edges of the mobile phone backplane plastic housing 20. A receiving groove 201a is provided in the mobile phone backplane plastic housing 20. The aluminum sheet 30 is installed in the receiving groove 201a. The aluminum sheet 30 is convexly provided with a buckle protrusion 30a. A buckle connecting portion 20a is provided on one side of the mobile phone backplane plastic housing 20. A buckling groove 201a is provided in the buckle connecting portion 20a. The buckle protrusion 30a is installed in the buckling groove 201a. A compensation glue layer 212a is provided on the surface of the buckle connecting portion 20a, and the compensation glue layer 212a is flush with the surface of the aluminum sheet 30.

[0061] As Figure 11 shown, the present application also provides a manufacturing method for a plastic forming and connecting structure for an imitation metal mobile phone backplane. The manufacturing method for the plastic forming and connecting structure for the imitation metal mobile phone backplane is manufactured by the plastic forming and connecting device 10 for the imitation metal mobile phone backplane described in any of the above embodiments.

[0062] S101 Install a plurality of the inserts 100 on the lower mold core 300 in sequence, cover the upper mold core 200 on the cavity 101 and close the mold;

[0063] S103 Preheat and raise the temperature of the inserts 100, the upper mold core 200 and the lower mold core 300, so that the temperature range of the inserts is 100°C - 120°C, the temperature range of the upper mold core is 70°C - 85°C, and the temperature range of the lower mold core is 70°C - 85°C;

[0064] S105 Inject the injection plastic into the injection runner 201 for injection molding;

[0065] S107 cools the cavity 101, and after mold opening, a plastic shell 20 of a mobile phone backplane with two high-brightness parting inclined surfaces 211a formed at the upper and lower edges is obtained;

[0066] S109 sprays paint and electroplates each parting surface on the surface of the plastic shell 20 of the mobile phone backplane, so that two high-brightness parting inclined surfaces 211a with a high-brightness edge effect are formed at the upper and lower edges of the plastic shell 20 of the mobile phone backplane, and a plastic shell 20 of the mobile phone backplane with a metallic texture is obtained;

[0067] S111 composites and connects the aluminum sheet 30 with the plastic shell 20 of the mobile phone backplane with a metallic texture to obtain a plastic formed connection structure.

[0068] In this embodiment, a plurality of plastic shells 20 of the mobile phone backplane with each parting surface are obtained by injection molding. At the same time, two high-brightness parting inclined surfaces 211a are formed at the upper and lower edges of the plastic shell 20 of the mobile phone backplane. The surface of the high-brightness parting inclined surface 211a is flat and clearly demarcated from the adjacent parting surface, so that after spraying paint and electroplating, the brightness difference between the high-brightness parting inclined surface 211a and the adjacent parting surface is obvious, and the metallic texture of the plastic shell 20 of the mobile phone backplane is obvious; when the aluminum sheet 30 is compositely connected with the plastic shell 20 of the mobile phone backplane with a metallic texture, the aluminum sheet and the plastic shell 20 of the mobile phone backplane are clamped through the buckle protrusion 30a, and the aluminum sheet and the plastic shell 20 of the mobile phone backplane are adhesively connected or heat-melted connected, so as to obtain a lightweight plastic formed connection structure; it can be understood that the temperature of the molten injection plastic is relatively high, the first annular inclined groove 202 of the upper mold core 200 and the second annular inclined groove 303 of the lower mold core 300 are in contact with the molten injection plastic, and the temperature difference between the molten injection plastic and the insert 100 is relatively small, while the temperature difference between the molten injection plastic and the upper mold core 200 and the lower mold core 300 is relatively large, so that the injection plastic rapidly cools to below the glass transition temperature Tg of PC polycarbonate within 0.2 s - 0.5 s, and the surface molecular chains of the inclined high-brightness parting inclined surface 211a formed by the injection plastic are frozen, reducing the movement and rearrangement of the molecular chains during the cooling process, so that the high-brightness parting inclined surface 211a formed by the injection plastic has a higher gloss; it can be understood that the temperature difference between the lower mold core 300 and the injection plastic of the molten injection plastic is relatively large, which is beneficial to the gloss of the high-brightness parting inclined surface 211a formed in the second annular inclined groove 303. However, when the temperature difference between the lower mold core 300 and the injection plastic of the molten injection plastic is relatively large, the shrinkage rate of the buckle connecting part 20a formed in the buckle forming groove 102 of the cavity 101 is relatively large, and the compensation glue layer 212a formed in the compensation glue groove 302 supplements the shrinkage space of the buckle connecting part 20a, so that the surface of the plastic shell 20 of the mobile phone backplane remains flat.

[0069] The manufacturing method of the formed connection structure of the imitation metal mobile phone backplane plastic, through the coordination of multiple processes, sequentially performs precision injection molding of the mobile phone backplane plastic housing 20, paints and electroplates each parting surface of the mobile phone backplane plastic housing 20, so that a high-brightness parting inclined surface 211a with a high-brightness edge is formed at the upper and lower edges of the mobile phone backplane plastic housing 20, and then the mobile phone backplane plastic housing 20 is compound-connected with the aluminum sheet 30, so that the obtained formed connection structure of the imitation metal mobile phone backplane plastic has the effects of structural light weight, high strength, and high-brightness edge metallic texture.

[0070] Further, for the high-brightness parting inclined surface 211a of the mobile phone backplane plastic housing 20 to form a high-brightness edge effect, it is necessary to perform high polishing on the first annular groove 202 and the second annular groove 303. Before sequentially installing the plurality of inserts 100 on the lower mold core 300 and covering the upper mold core 200 on the cavity 101 for mold clamping, the following steps are further included:

[0071] Perform primary polishing on the first annular groove 202 and the second annular groove 303 through a mechanical mirror polishing machine;

[0072] Then perform secondary polishing through an ultrasonic polishing machine.

[0073] In this embodiment, when the mechanical mirror polishing machine performs primary polishing, most of the protrusions and depressions on the surfaces of the first annular groove 202 and the second annular groove 303 are removed, reducing the polishing difficulty of the subsequent ultrasonic polishing machine; when the ultrasonic polishing machine performs secondary polishing, the tiny defects and scratches remaining after the mechanical polishing of the first annular groove 202 and the second annular groove 303 are removed, further improving the smoothness and gloss of the surfaces of the first annular groove 202 and the second annular groove 303, so as to form a smooth high-brightness parting inclined surface 211a on the formed surfaces of the first annular groove 202 and the second annular groove 303.

[0074] Further, since the surface roughness of the first annular groove 202 and the second annular groove 303 is low and it is easy to wear, it is necessary to protect the surfaces of the first annular groove 202 and the second annular groove 303. After performing high polishing on the first annular groove 202 and the second annular groove 303, the following steps are further included:

[0075] Deposit diamond-like carbon (DLC) on the surfaces of the first annular inclined groove 202 and the second annular inclined groove 303 to form a DLC coating. In this embodiment, the DLC coatings on the surfaces of the first annular inclined groove 202 and the second annular inclined groove 303 have high hardness and good wear resistance, can resist wear and scratches during use, thereby extending the service life of the first annular inclined groove 202 and the second annular inclined groove 303. The DLC coating can also significantly reduce the adhesion force between the first annular inclined groove 202 and the second annular inclined groove 303 and the high-brightness parting inclined surface 211a, reduce the occurrence of mold sticking phenomenon, thereby improving production efficiency and product quality.

[0076] In one embodiment, when injecting the injection molding material into the injection molding runner 201 for injection molding, the injection molding pressure is 80 MPa - 120 MPa, the holding pressure after injection molding is 50 MPa - 90 MPa, and the holding time of injection molding is 5 s - 10 s. In this embodiment, the mobile phone backplane plastic housing 20 has a thin-wall structure, and the flow resistance of the molten injection molding material is large. When the injection molding pressure is less than 80 MPa, the effect of filling the cavity 101 with the molten injection molding material is poor, resulting in missing glue or shrinkage marks in the molding; when the injection molding pressure is greater than 120 MPa, it may cause flash and increased internal stress in the formed mobile phone backplane plastic housing 20. The injection molding pressure that needs to be controlled for the mobile phone backplane plastic housing 20 is 80 MPa - 120 MPa to enable the molten injection molding material to fill the cavity 101 while avoiding the negative impacts brought by excessive pressure; when the cavity 101 is filled with the injection molding material, a holding pressure of 50 MPa - 90 MPa is applied to the injection molding material to maintain the density of the injection molding material and reduce defects such as shrinkage; when the holding time is less than 5 s, the holding process cannot fully compensate for the shrinkage of the injection molding material; when the holding time is greater than 10 s, during the holding time process, it may cause unnecessary internal stress in the injection molding material; the holding time of injection molding being 5 s - 10 s enables the mobile phone backplane plastic housing 20 to be fully compensated for shrinkage and shaped during the cooling process, avoiding the negative impacts brought by too long holding time.

[0077] Further, in one embodiment, the injection molding material is PC (polycarbonate), and the temperature range of the injection molding material is 280°C - 320°C. In this embodiment, PC polycarbonate has relatively high tensile, compressive, and flexural strengths, and PC polycarbonate maintains stable performance within a relatively wide temperature range and is not prone to thermal deformation. Preheat and raise the temperature of the insert 100, the upper mold core 200, and the lower mold core 300, so that the heat loss of PC polycarbonate during the injection molding process is reduced, thereby improving the flowability of the injection molding material and reducing the risk of deformation and cracking of the formed mobile phone backplane plastic housing 20.

[0078] Furthermore, the temperature difference between the insert 100 and the upper mold core 200 and the lower mold core 300 is less than 20°C-30°C. In the present embodiment, when the temperature difference between the insert 100 and the upper mold core 200 and the lower mold core 300 is too large, the molten injection plastic will stagnate due to the inconsistent cooling speed when flowing through the area with a large temperature difference. The stagnation of the molten injection plastic will further cause flow marks, thereby affecting the appearance quality. Too large a temperature difference may also cause internal stress to be generated inside the product, thereby causing deformation or cracking during subsequent use. Too large a temperature difference may also cause the molten injection plastic to flow poorly when filling the cavity 101, thereby causing insufficient filling and other defects. By controlling the temperature difference between the insert 100 and the upper mold core 200 and the lower mold core 300, the stagnation of the molten injection plastic to generate flow marks is avoided, thereby improving the quality and production efficiency of the molded mobile phone back panel plastic shell 20.

[0079] In one embodiment, the mold cavity 101 is cooled, and the cooling time is 15s-25s. In this embodiment, when the cooling time of the mobile phone back panel plastic shell 20 is less than 15s, the heat inside the mobile phone back panel plastic shell 20 cannot be fully dissipated, and the mobile phone back panel plastic shell 20 continues to shrink due to the release of internal stress after demoulding, resulting in the instability and deviation of the size of the mobile phone back panel plastic shell 20; when the cooling time is too long, the injection molding process of the mobile phone back panel plastic shell 20 is long, thereby affecting the production efficiency; controlling the cooling time to 15s-25s ensures the quality and production efficiency of the mobile phone back panel plastic shell 20, and reduces energy consumption and production costs.

[0080] In one embodiment, each parting surface on the surface of the mobile phone back plate plastic shell 20 is sprayed with paint and electroplated so that the upper and lower edges of the mobile phone back plate plastic shell 20 form a highlight parting slope 211a with a highlight edge, and a mobile phone back plate plastic shell 20 with a metallic texture is obtained, comprising the following steps:

[0081] Spraying primer on each parting surface of the mobile phone back panel plastic shell 20;

[0082] Vacuum electroplating metal paint on the mobile phone back plate plastic shell 20 sprayed with the primer, so that each parting surface of the mobile phone back plate plastic shell 20 obtains a metal paint layer;

[0083] Spraying colorless transparent middle-layer paint on the two highlight parting slopes 211a of the upper and lower edges of the mobile phone back plate plastic shell 20 to form a highlight parting slope 211a with a metallic texture, and spraying colored transparent middle-layer paint on the other parting surfaces of the mobile phone back plate plastic shell 20 to form a parting surface with a metallic texture;

[0084] Spraying bright surface protective paint on the mobile phone back panel plastic shell 20;

[0085] Laser engraving will be performed on the plastic housing 20 of the mobile phone back panel. In this embodiment, the base coat can enhance the adhesion between the metal paint and the plastic housing, fill the tiny defects on the surface of the plastic housing, provide a uniform and smooth base for the metal paint layer, and make the metallic texture more uniform and delicate; the colored transparent middle coat has a transparent base, and specific pigments or dyes are added to the colored transparent middle coat to give it a certain color effect. When the colored transparent middle coat is sprayed on the metal paint layer, the plastic housing 20 of the mobile phone back panel obtains a metallic texture effect of other colors; the colorless transparent middle coat is transparent. When the colorless transparent middle coat is sprayed on the metal paint layer of the high-brightness parting slope 211a, the high-brightness parting slope 211a shows a high-brightness edge effect with metallic luster; the high-gloss protective paint can also improve the weather resistance of the plastic housing 20 of the mobile phone back panel and provide protection against scratches, abrasions and other physical damages in daily use, thereby extending the service life of the plastic housing 20 of the mobile phone back panel. The high-gloss protective paint can increase the gloss of the plastic housing 20 of the mobile phone back panel and further improve the metallic texture of the plastic housing 20 of the mobile phone back panel; laser engraving is performed on the plastic housing 20 of the mobile phone back panel, so that a matte surface is formed on the engraved part of the plastic housing 20 of the mobile phone back panel, thereby making the appearance texture and style of the plastic housing 20 of the mobile phone back panel more variable.

[0086] Furthermore, the aluminum sheet can be electroplated to make the appearance of the aluminum sheet similar to that of the plastic housing 20 of the mobile phone back panel. Before connecting the aluminum sheet to the plastic housing 20 of the mobile phone back panel with a metallic texture after painting and electroplating each parting surface on the surface of the plastic housing 20 of the mobile phone back panel to obtain a plastic forming connection structure, the following steps are further included:

[0087] The aluminum material is cut by CNC to obtain an aluminum substrate sheet;

[0088] The aluminum substrate sheet is polished;

[0089] The polished aluminum substrate sheet is electroplated with a metal layer and subjected to coloring treatment to obtain an aluminum sheet. In this embodiment, through the CNC numerical control machine cutting technology, the required shape and size of the aluminum substrate sheet are accurately cut from the aluminum material, ensuring the accuracy and consistency of the aluminum sheet; electroplating a metal layer on the polished aluminum substrate sheet increases the metallic texture of the aluminum sheet, enhances the corrosion resistance, hardness and wear resistance of the aluminum sheet, and the coloring treatment enables the aluminum sheet to more accurately match the color and design of the plastic housing 20 of the mobile phone back panel, thereby ensuring the consistency of the appearance style between the aluminum sheet and the plastic housing 20 of the mobile phone back panel.

[0090] In one embodiment, the present application further provides a manufacturing method for a forming connection structure of a plastic for a metal-like mobile phone backplane. The method is carried out by using the forming connection device for the plastic of the metal-like mobile phone backplane. A plurality of the inserts are sequentially installed on the lower die core, and the upper die core is covered on the cavity for mold clamping. The inserts, the upper die core and the lower die core are heated and temperature is raised by a heating device, so that the temperature range of the inserts is 100°C - 120°C, the temperature range of the upper die core is 70°C - 85°C, and the temperature range of the lower die core is 70°C - 85°C. Injection plastic is introduced into the injection runner for injection molding. The cavity is cooled, and after mold opening, a mobile phone backplane plastic shell with two high-brightness parting inclined surfaces formed at the upper and lower edges is obtained. The respective parting surfaces on the surface of the mobile phone backplane plastic shell are painted and electroplated, so that the upper and lower edges of the mobile phone backplane plastic shell form high-brightness parting inclined surfaces with a high-brightness edge effect, and a mobile phone backplane plastic shell with a metallic texture is obtained. An aluminum sheet is connected to the mobile phone backplane plastic shell to obtain a forming connection structure of a plastic for a metal-like mobile phone backplane.

[0091] The forming connection device for the plastic of the metal-like mobile phone backplane includes inserts, an upper die core and a lower die core. A plurality of installation grooves are formed in the circumferential direction of the lower die core. The number of the inserts is plural, and each insert is installed in a corresponding installation groove. The plurality of inserts are sequentially spliced along the circumferential direction of the lower die core. The plurality of inserts and the lower die core together form a cavity. The upper die core is covered on the cavity. An injection runner is formed in the upper die core. A snap forming groove and a shell groove which are communicated with each other are formed in the cavity. The shell groove is used for forming the main body of the mobile phone backplane plastic shell, and the snap forming groove is used for forming a snap connection part connected to the aluminum sheet. The injection runner is communicated with the shell groove. The lower die core is provided with a compensation glue groove communicated with the snap forming groove, and the compensation glue groove is used for reducing the deformation caused by plastic shrinkage.

[0092] A first annular inclined groove communicated with the cavity is formed in the circumferential direction of the upper die core along the cavity, and a second annular inclined groove communicated with the cavity is formed in the circumferential direction of the lower die core along the cavity. The first annular inclined groove and the second annular inclined groove are used for forming two high-brightness parting inclined surfaces at the upper and lower edges of the mobile phone backplane plastic shell.

[0093] The insert includes an integrally formed raised portion and a movable portion. The raised portion of each of the inserts is abutted in sequence along the circumference of the cavity. The raised portion of each of the inserts is adjacent to the cavity. Each of the movable portions is installed in the installation groove. The movable portion is also provided with a stop block. The lower die core is provided with a plurality of stop grooves in the circumference. Each of the stop blocks is embedded in the corresponding stop groove. An assembly groove for demoulding is provided at one end of the movable portion away from the raised portion. A first guide bevel is provided on the side of the raised portion adjacent to the upper die core. The upper die core is provided with a first abutting portion, and the first abutting portion is attached to the first guide bevel; and / or a second guide bevel is provided on the side of the raised portion adjacent to the lower die core. The lower die core is provided with a second abutting portion, and the second abutting portion is attached to the second guide bevel. The thickness difference between the buckle molding groove and the housing groove is 0.2mm-0.7mm, and the groove depth of the compensation rubber groove is 0.001mm-0.005mm. The upper mold core is provided with a first heating channel, the insert is provided with a second heating channel, and the lower mold core is provided with a third heating channel. The first heating channel, the second heating channel and the third heating channel are respectively used to connect to the corresponding heating equipment, so that the temperature range of the insert is 100℃-120℃, the temperature range of the upper mold core is 70℃-85℃, and the temperature range of the lower mold core is 70℃-85℃. The molding connection equipment of the imitation metal mobile phone back panel plastic also includes a plurality of inclined ejectors, the upper mold core is provided with an ejection channel, and the ejection channels are arranged at intervals along the circumference of the cavity, each of the inclined ejectors is installed on the corresponding ejection channel, and the ejection channel is inclined toward the center of the cavity. The compensating rubber groove is a circular arc transition surface structure.

[0094] The molding connection structure of the imitation metal mobile phone back panel plastic comprises a mobile phone back panel plastic shell and an aluminum sheet obtained by injection molding using the molding connection equipment for the imitation metal mobile phone back panel plastic, wherein the upper and lower edges of the mobile phone back panel plastic shell are respectively formed with parting slopes, a receiving groove is provided in the mobile phone back panel plastic shell, the aluminum sheet is installed in the receiving groove, a snap protrusion is convexly provided on the aluminum sheet, a snap connection part is provided on one side of the mobile phone back panel plastic shell, a snap connection part is provided in the snap connection part, the snap protrusion is installed in the snap connection groove, a compensation adhesive layer is provided on the surface of the snap connection part, and the compensation adhesive layer is flush with the surface of the aluminum sheet.

[0095] Compared with the prior art, the present invention has at least the following advantages:

[0096] The above-mentioned forming and connecting device 10 for plastic of the metal-like mobile phone back panel. After multiple inserts 100 are spliced, a cavity 101 is formed with the upper die core 200 and the lower die core 300. The upper die core 200, the lower die core 300 and multiple inserts 100 are separately and precisely processed, so that the plastic shell 20 of the mobile phone back panel obtains the effect of more parting surfaces; the thickness of the snap connection part 20a of the plastic shell 20 of the mobile phone back panel is relatively thick. After the snap connection part 20a is cooled, internal shrinkage occurs, resulting in a thickness difference with the surface of the aluminum sheet 30. The formed compensation glue layer in the compensation glue groove 302 is flush with the surface of the aluminum sheet 30 after molding, reducing the height difference generated on the surface between the aluminum sheet 30 and the plastic shell 20 of the mobile phone back panel; two inclined high-brightness parting inclined surfaces 211a are formed in the first annular inclined groove 202 and the second annular inclined groove 303 of the plastic shell 20 of the mobile phone back panel, so that the surface of the inclined high-brightness parting inclined surface 211a is flat, and the boundary between the high-brightness parting inclined surface 211a and the adjacent parting surface is obvious; the inclined high-brightness parting inclined surface 211a formed on the plastic shell 20 of the mobile phone back panel is prone to parallax relative to the plane, making the incident light easier to reflect, thereby covering up the tiny defects generated during the injection molding process on the high-brightness parting inclined surface 211a. Furthermore, it is easier to generate a brightness difference between the inclined high-brightness parting inclined surface 211a and the plane of the adjacent parting surface, and the high-brightness edge effect formed by the high-brightness parting inclined surface 211a of the plastic shell 20 of the mobile phone back panel is better.

[0097] A manufacturing method for the forming and connecting structure of the plastic of the metal-like mobile phone back panel. Through the coordination of multiple processes, the plastic shell 20 of the mobile phone back panel is successively and precisely injection molded, and the parting surfaces of the plastic shell 20 of the mobile phone back panel are painted and electroplated, so that high-brightness parting inclined surfaces 211a with high-brightness edges are formed at the upper and lower edges of the plastic shell 20 of the mobile phone back panel. Then, the plastic shell 20 of the mobile phone back panel is compound-connected with the aluminum sheet 30, so that the obtained forming and connecting structure of the plastic of the metal-like mobile phone back panel has the effects of lightweight structure, high strength, and high-brightness edge metallic texture.

[0098] The above-described embodiments merely represent several implementation manners of the present disclosure. The description is relatively specific and detailed, but it should not be construed as a limitation on the scope of the disclosed patent. It should be noted that for those of ordinary skill in the art, without departing from the concept of the present disclosure, several deformations and improvements can still be made, and these all belong to the protection scope of the present disclosure. Therefore, the protection scope of the present disclosure patent shall be subject to the appended claims.

Claims

1. A molding and connecting device for imitating metal mobile phone back panel plastic, characterized in that: It comprises an insert, an upper mold core and a lower mold core, wherein the lower mold core is provided with a plurality of mounting grooves in the circumference thereof, the number of the inserts is plural, each of the inserts is installed in the corresponding mounting groove, the plurality of inserts are sequentially spliced ​​along the circumference of the lower mold core, the plurality of inserts and the lower mold core jointly form a cavity, the upper mold core is covered in the cavity, an injection molding flow channel is provided in the upper mold core, a connected buckle molding groove and a shell groove are formed in the cavity, the shell groove is used to mold the main body of the plastic shell of the back plate of the mobile phone, the buckle molding groove is used to mold the buckle connection part connected with the aluminum sheet, the injection molding flow channel is connected to the shell groove, the lower mold core is provided with a compensating rubber groove connected to the buckle molding groove, and the compensating rubber groove is used to reduce the deformation caused by the shrinkage of the plastic; The upper mold core is provided with a first annular bevel groove connected to the mold cavity along the circumference of the mold cavity, and the lower mold core is provided with a second annular bevel groove connected to the mold cavity along the circumference of the mold cavity. The first annular bevel groove and the second annular bevel groove are used to form two highlighted parting slopes on the upper and lower edges of the plastic shell of the back panel of the mobile phone.

2. The molding and connecting device of the imitation metal mobile phone back panel plastic according to claim 1, characterized in that: The insert includes an integrally formed protrusion and a movable portion, the protrusion of each insert abuts in sequence along the circumference of the cavity, the protrusion of each insert is adjacent to the cavity, each movable portion is installed in the installation groove, and the movable portion is also protruding with a limit block, and a plurality of limit grooves are opened in the circumference of the lower mold core, and each limit block is embedded in the corresponding limit groove.

3. The molding and connecting device of the imitation metal mobile phone back panel plastic according to claim 2, characterized in that: An assembly groove for demoulding is formed at one end of the movable part away from the protruding part.

4. The molding and connecting device for imitating metal mobile phone back panel plastic according to claim 2, characterized in that: A first guide slope is disposed on one side of the protruding portion adjacent to the upper die core, and a first abutting portion is convexly disposed on the upper die core, and the first abutting portion is attached to the first guide slope; and / or, A second guide slope is arranged on one side of the protruding portion adjacent to the lower die core, and a second abutting portion is convexly arranged on the lower die core, and the second abutting portion is attached to the second guide slope.

5. The molding and connecting device of the imitation metal mobile phone back panel plastic according to claim 1, characterized in that: The thickness difference between the buckle forming groove and the shell groove is 0.2mm-0.7mm, and the groove depth of the compensation glue groove is 0.001mm-0.005mm.

6. The molding and connecting device for imitating metal mobile phone back panel plastic according to claim 1, characterized in that: A first heating channel is provided in the upper mold core, a second heating channel is provided in the insert, and a third heating channel is provided in the lower mold core. The first heating channel, the second heating channel and the third heating channel are respectively used to be connected to corresponding heating devices so that the temperature range of the insert is 100°C-120°C, the temperature range of the upper mold core is 70°C-85°C, and the temperature range of the lower mold core is 70°C-85°C.

7. The molding and connecting device for imitating metal mobile phone back panel plastic according to claim 6, characterized in that: The molding and connection equipment for the imitation metal mobile phone back panel plastic also includes a plurality of inclined ejectors, the upper mold core is provided with an ejection channel, the ejection channels are arranged at intervals along the circumference of the cavity, each of the inclined ejectors is installed on the corresponding ejection channel, and the ejection channel is arranged inclined toward the center of the cavity.

8. The molding and connecting device for imitating metal mobile phone back panel plastic according to claim 1, characterized in that: The compensating rubber groove is an arc transition curved surface structure.

9. A molding connection structure of a plastic imitation metal mobile phone back panel, characterized in that: A mobile phone back panel plastic shell and an aluminum sheet obtained by injection molding using a molding and connecting device for imitation metal mobile phone back panel plastic according to any one of claims 1 to 8, wherein the upper and lower edges of the mobile phone back panel plastic shell are respectively formed with highlighted parting slopes, a receiving groove is provided in the mobile phone back panel plastic shell, the aluminum sheet is installed in the receiving groove, the aluminum sheet is convexly provided with a snap protrusion, a snap connection part is provided on one side of the mobile phone back panel plastic shell, the snap connection part is provided with a snap groove, the snap protrusion is installed in the snap groove, and a compensation adhesive layer is provided on the surface of the snap connection part, and the compensation adhesive layer is flush with the surface of the aluminum sheet.

10. A method for manufacturing a molded connection structure of a plastic imitation metal mobile phone back panel, which is manufactured by the molded connection device of the plastic imitation metal mobile phone back panel according to any one of claims 1 to 8, characterized in that: The plurality of inserts are sequentially mounted on the lower mold core, and the upper mold core is covered on the mold cavity for mold closing; The insert, the upper mold core and the lower mold core are heated by a heating device so that the temperature range of the insert is 100° C.-120° C., the temperature range of the upper mold core is 70° C.-85° C., and the temperature range of the lower mold core is 70° C.-85° C.; Passing the injection material into the injection molding runner for injection molding; The cavity is cooled, and after the mold is opened, a mobile phone back panel plastic shell with two highlighted parting slopes formed on the upper and lower edges is obtained; The parting surfaces on the surface of the mobile phone back plate plastic shell are sprayed with paint and electroplated, so that the upper and lower edges of the mobile phone back plate plastic shell form high-brightness parting slopes with high-brightness edge effects, thereby obtaining a mobile phone back plate plastic shell with a metallic texture; The aluminum sheet is connected to the plastic shell of the mobile phone back panel to obtain a molded connection structure of the imitation metal mobile phone back panel plastic.

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