A manufacturing process for mobile phone mid-frame

Abstract

This invention discloses a manufacturing process for a mobile phone mid-frame, belonging to the technical field of manufacturing processes for mid-frame structures in portable smart devices. The process involves first preparing a die-cast mid-plate, then preparing several frame components, and finally connecting the die-cast mid-plate to at least two frame components using laser welding. After laser welding, the mid-plate-frame components are machined to create injection molding grooves at predetermined positions on both the die-cast mid-plate and the frame components. Next, the machined mid-plate-frame components are subjected to in-mold injection molding. Finally, the molded workpiece is precision machined and surface-treated to obtain the finished product. This invention's manufacturing process for a mobile phone mid-frame solves the technical problems of low-end products, limited processes, high processing costs, and unstable quality found in existing technologies.

Description

Technical Field

[0001] This invention relates to the technical field of manufacturing processes for the mid-frame structure of portable smart devices, and in particular to a manufacturing process for a mobile phone mid-frame. Background Technology

[0002] Portable smart devices refer to small electronic devices that can be carried and used, possessing independent power sources, computing power, and various intelligent functions. Examples include smartphones, tablets, portable game consoles, mini projectors, portable air purifiers, smart bracelets / watches, and so on. These devices have become deeply integrated into people's daily lives and are constantly evolving and innovating.

[0003] In the development trend of portable smart devices such as smartphones, as users demand larger image sizes and lighter weights, in order to enhance their structural strength, there is an increasing trend to replace plastic materials with metal materials for the internal support frame structure. Moreover, replacing plastic parts with metal parts for the mid-frame structure of portable smart devices also has advantages such as better heat dissipation.

[0004] Generally speaking, when manufacturing a structural frame for a portable smart device with external parts and an internal metal bracket, it is necessary to use metal processing equipment to perform integrated machining of the external frame and the internal structure, or to manufacture the external metal frame and the internal metal bracket separately and then assemble them; or to use a method of casting the external frame and the internal metal bracket as a single piece.

[0005] Based on this, Chinese patent CN108605061B discloses a mobile phone and its frame. The mobile phone frame includes an outer frame, a middle plate, and a first plastic component. The outer frame is obtained by bending titanium alloy strips to a predetermined size. The middle plate is disposed inside the outer frame. The first plastic component fixes the outer edge of the middle plate to the inner sidewall of the outer frame by injection molding. Because the mobile phone frame uses a titanium alloy outer frame and an aluminum middle plate, and is fixed by injection molding, the frame structure is simple, easy to manufacture, has reliable strength, and an attractive appearance. The process involves fixing the frame by injection molding followed by CNC machining and then a second injection molding, ensuring consistency and accuracy in the manufacturing process.

[0006] However, the aforementioned mobile phones and their frames still suffer from limitations in manufacturing processes, high processing costs, and unstable quality. Specifically, considering existing technologies, if metal materials are used for molding and processing, and the external frame and internal structure are machined as a single unit, there are technical problems such as excessively high appearance standards, high manufacturing costs, and low productivity. If a process of manufacturing the metal external frame and internal metal support separately and then assembling them occurs, problems such as difficulty in controlling assembly tolerances, low joint strength, and high assembly costs arise. Furthermore, while the process of casting the external frame and internal support as a single unit has the advantage of ease of manufacturing, it also presents technical problems such as low finished product quality, low-end products, and poor controllability. Moreover, existing mobile phones and portable smart devices have high appearance requirements, and some products require aesthetic treatments such as anodizing; existing mobile phone mid-frame technology cannot achieve this. Summary of the Invention

[0007] Therefore, it is necessary to provide a manufacturing process for mobile phone mid-frames to address the technical problems of existing technologies, such as low-end products, limited processes, high processing costs, and unstable quality.

[0008] A manufacturing process for a mobile phone mid-frame includes the following steps:

[0009] S1: Preparation of the middle plate die casting: First, the main structure of the middle plate is prepared by metal die casting process. Then, the periphery of the main structure of the middle plate is machined to remove the die casting draft angle and control the dimensional accuracy of the main structure of the middle plate so that it is suitable for subsequent welding processes.

[0010] S2: Prepare several frame parts respectively: Use rollers to roll the aluminum material roll to control the cross-section of the aluminum material to meet the preset size requirements, and then level and cut it to the preset length;

[0011] Next, the cut strips are placed into the die and stamped to form the shape of the pre-set frame pieces, so that the short side of each frame piece is perpendicular to its long side.

[0012] Then, the formed frame parts are placed into the fixture of the machining center and machined to the required size using CNC; the shape and size of the inner welding groove of each frame part are machined to the preset accuracy using CNC processes;

[0013] After the stamping and CNC processes, the perimeter of a medium-sized die-cast part shall be connected by at least two frame members.

[0014] S3: Connect the die-cast middle plate to at least two side frame parts using laser welding process: simultaneously load the die-cast middle plate and all side frame parts into the welding fixture, ensuring accurate positioning of both; start the laser welding machine, align the laser beam with the part to be welded, and stably connect the die-cast middle plate to its surrounding side frame parts.

[0015] S4: After laser welding is completed, the middle plate-frame component is machined to prepare the injection molding grooves at the preset positions of the middle plate die casting and the frame component.

[0016] S5: In-mold injection molding of the completed middle plate-frame component: First, a pre-treatment process of degreasing and cleaning is used to thoroughly clean the parts; then, a T-process is used to generate micropores to facilitate the completion of the nano-injection molding process; finally, nano-injection molding is used to fill the predetermined positions of the middle plate-frame component with plastic.

[0017] S6: Mechanical finishing after in-mold injection molding: The in-mold injection molded part is placed on the fixture for precise positioning and machined in one go using a multi-axis machining center; then, the outer surface of the middle frame is sandblasted and anodized to produce the mobile phone middle plate product.

[0018] Furthermore, a mobile phone mid-frame structure that is easy to form using the aforementioned manufacturing process includes: a mid-plate forming part, a frame forming part, and auxiliary forming parts; at least two frame forming parts are arranged around the periphery of the mid-plate forming part, and the inner side of each frame forming part is connected to the edge surface of the mid-plate forming part; a plurality of auxiliary forming parts are distributed in the mid-plate forming part, on the inner side of the frame forming part, and between the mid-plate forming part and the frame forming part.

[0019] Furthermore, the middle plate forming part has a main structure and a side standing edge structure.

[0020] Furthermore, the side support structure is arranged around the perimeter of the main structure.

[0021] Furthermore, the frame forming part has at least two surrounding frames, an appearance shaping part, an inlay groove, and a welding part.

[0022] Furthermore, all the surrounding frames are connected end to end in sequence to form a ring.

[0023] Furthermore, each of the surrounding frames is provided with an appearance shaping part on its outer side, and each of the surrounding frames is provided with an inlay groove and a welding part on its inner side, with the inlay groove and the welding part being arranged adjacent to each other.

[0024] Furthermore, the side-standing structure is matched and connected to the inlay groove.

[0025] Furthermore, the frame described herein includes a frame body, an injection groove, and an insertion port.

[0026] Furthermore, a plurality of injection grooves are evenly distributed within the surrounding frame body, and each of the insertion ports is correspondingly disposed through the surrounding frame body.

[0027] In summary, the manufacturing process for a mobile phone frame of the present invention involves first preparing a die-cast mid-plate, then preparing several frame parts, and then connecting the die-cast mid-plate to at least two frame parts using laser welding. After laser welding, the mid-plate-frame parts are machined to create injection molding grooves at predetermined positions on the die-cast mid-plate and frame parts. Next, the machined mid-plate-frame parts are subjected to in-mold injection molding. Finally, the workpiece is in-mold molded and then precision machined and surface treated to obtain the finished product. Using the process disclosed in this invention reduces costs by changing from all machining to partial machining, reducing machining volume by 70% and overall cost by 40%. Furthermore, it offers the advantage of stable quality because the welding method between the frame and mid-plate successfully solves the problem of anodizing and coloring die-cast aluminum, allowing for precise completion of each process with minimal machining. Additionally, this invention improves production efficiency, reducing the total processing time from 58 minutes to 37 minutes, increasing efficiency by 36%. Therefore, the manufacturing process of the mobile phone mid-frame of the present invention solves the technical problems of low-end products, limited process, high processing cost and unstable quality in the prior art. Attached Figure Description

[0028] Figure 1 This is a schematic diagram of the manufacturing process of a mobile phone mid-frame according to the present invention;

[0029] Figure 2 This is a schematic diagram of a mid-frame structure that is easy to mold according to the present invention;

[0030] Figure 3 This is a schematic diagram of a middle frame structure that is easy to form according to the present invention;

[0031] Figure 4 This is an exploded structural diagram of a middle frame structure that is easy to form according to the present invention.

[0032] Figure 5 This is an exploded structural diagram of a middle frame structure that is easy to form according to the present invention.

[0033] Figure 6 This is a schematic diagram of the manufacturing process of a mobile phone mid-frame according to the present invention;

[0034] Figure 7This is a schematic diagram of another processing flow for the manufacturing process of a mobile phone mid-frame according to the present invention. Detailed Implementation

[0035] To make the above-mentioned objects, features, and advantages of the present invention more apparent and understandable, specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings. Many specific details are set forth in the following description to provide a thorough understanding of the present invention. However, the present invention can be practiced in many other ways different from those described herein, and those skilled in the art can make similar modifications without departing from the spirit of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0036] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0037] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this invention, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0038] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise explicitly limited. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0039] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "over," and "on top" of the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0040] It should be noted that when an element is referred to as being "fixed to" or "set on" another element, it can be directly on the other element or there may be an intervening 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 intervening element. The terms "vertical," "horizontal," "upper," "lower," "left," "right," and similar expressions used herein are for illustrative purposes only and do not represent the only possible implementation.

[0041] Please see Figure 1 The present invention discloses a manufacturing process for a mobile phone mid-frame, which includes the following steps:

[0042] S1: Preparation of the middle plate die casting: First, the main structure of the middle plate is prepared by metal die casting process. Then, the periphery of the main structure of the middle plate is machined to remove the die casting draft angle and control the dimensional accuracy of the main structure of the middle plate so that it is suitable for subsequent welding processes.

[0043] S2: Prepare several frame parts respectively: Use rollers to roll the aluminum material roll to control the cross-section of the aluminum material to meet the preset size requirements, and then level and cut it to the preset length;

[0044] Next, the cut strips are placed into the die and stamped to form the shape of the pre-set frame pieces, so that the short side of each frame piece is perpendicular to its long side.

[0045] Then, the formed frame parts are placed into the fixture of the machining center and machined to the required size using CNC; the shape and size of the inner welding groove of each frame part are machined to the preset accuracy using CNC processes;

[0046] After the stamping and CNC processes, the perimeter of a medium-sized die-cast part shall be connected by at least two frame members.

[0047] S3: Connect the die-cast middle plate to at least two side frame parts using laser welding process: simultaneously load the die-cast middle plate and all side frame parts into the welding fixture, ensuring accurate positioning of both; start the laser welding machine, align the laser beam with the part to be welded, and stably connect the die-cast middle plate to its surrounding side frame parts.

[0048] S4: After laser welding is completed, the middle plate-frame component is machined to prepare the injection molding grooves at the preset positions of the middle plate die casting and the frame component.

[0049] S5: In-mold injection molding of the completed middle plate-frame component: First, a pre-treatment process of degreasing and cleaning is used to thoroughly clean the parts; then, a T-process is used to generate micropores to facilitate the completion of the nano-injection molding process; finally, nano-injection molding is used to fill the predetermined positions of the middle plate-frame component with plastic.

[0050] S6: Mechanical finishing after in-mold injection molding: The in-mold injection molded part is placed on the fixture for precise positioning and machined in one go using a multi-axis machining center; then, the outer surface of the middle frame is sandblasted and anodized to produce the mobile phone middle plate product.

[0051] Specifically, in the manufacturing process of a mobile phone mid-frame according to the present invention, the machining allowance can be reduced. For example, for the structure of the mid-plate die-casting part, the structure that originally required machining can now be die-cast in one step using the metal die-casting process, which can reduce the overall cost of the original machining solution by more than 40%.

[0052] Furthermore, the mobile phone mid-frame product manufactured using the manufacturing process of this invention can have its appearance optimized through anodizing. For example, in the original integral die-casting process, the high silicon content of the die-cast aluminum makes it impossible to achieve an anodized appearance. However, by using the process of this invention, the frame perimeter can be manufactured using AL6063 profile, which is easily anodized; thus, the problem of difficulty in achieving anodizing in the original process is solved.

[0053] Furthermore, the present invention also has the advantage of stable quality because the medium plate product is precision machined after laser welding; therefore, the overall dimensions of the medium plate product are stable, reducing the appearance and dimensional defects in the processing process; and the yield rate of good products can be increased to over 92%.

[0054] Furthermore, by adopting the technical solution of the present invention, the overall structure of the mobile phone mid-plate product can be changed to a split structure. When a certain component malfunctions, there is no need to scrap the whole product; only the individual split component needs to be scrapped, thereby reducing the cost of material scrapping.

[0055] Furthermore, products that use laser welding to connect the middle plate and the frame components can have the advantages of good structural strength and no deformation.

[0056] For further information, please refer to [link / reference]. Figures 2 to 5 A mid-frame structure that is easy to form using the aforementioned manufacturing process for mobile phone mid-frames includes: a mid-plate forming part 1, a frame forming part 2, and auxiliary forming parts 3; at least two frame forming parts 2 are arranged around the periphery of the mid-plate forming part 1, and the inner side of each frame forming part 2 is connected to the edge surface of the mid-plate forming part 1; a plurality of auxiliary forming parts 3 are distributed in the mid-plate forming part 1, on the inner side of the frame forming part 2, and between the mid-plate forming part 1 and the frame forming part 2.

[0057] Furthermore, the middle plate forming part 1 has a main body structure 101 and a side standing edge structure 102; the side standing edge structure 102 is arranged around the periphery of the main body structure 101.

[0058] Furthermore, the frame forming part 2 has at least two surrounding frames 201, an appearance shaping part 202, an inlay groove 203, and a welding part 204; all the surrounding frames 201 are connected end to end in sequence to form a ring, the appearance shaping part 202 is provided on the outer side of each surrounding frame 201, and the inlay groove 203 and the welding part 204 are provided on the inner side of each surrounding frame 201, the inlay groove 203 and the welding part 204 are arranged adjacent to each other; the side standing edge structure 102 is matched and connected to the inlay groove 203.

[0059] Specifically, after all the surrounding frames 201 sequentially form a closed ring, each of the inlay slots 203 provided on its inner side can be connected end to end to communicate with each other, thereby allowing the side standing edge structures 102 provided on the periphery of the main structure 101 to be inlaid therein. Subsequently, a laser welding process can be used to add solder to the welding portion 204 to securely inlay the side standing edge structure 102 into the inlay slot 203. More specifically, the user can use processes such as anodizing to treat the cancerous shaped portion 202 to achieve the desired aesthetic appearance.

[0060] Furthermore, a portion of the surrounding frame 201 is provided with a surrounding frame body 201a, an injection groove 201b, and an insertion portion 201c; a plurality of injection grooves 201a are evenly distributed in the surrounding frame body 201a, and each insertion portion 201c is correspondingly disposed through the surrounding frame body 201a.

[0061] Furthermore, the main molding material of the auxiliary molding part 3 is PC+GF20. The main functions of the auxiliary molding part 3 include: firstly, some parts of the mobile phone frame need to be insulated; therefore, it is necessary to remove the metal and fill it with plastic; secondly, it plays an auxiliary connecting role to achieve a stable connection of the middle plate components.

[0062] Specifically, the injection groove 201b is used for the connection and attachment of the injection molded part during in-mold injection molding, and the insertion part 201c is used to match the connectors and other components of mobile phones and portable terminals.

[0063] Specifically, such as Figure 2 As shown, in a specific embodiment, the middle plate forming part 1 is made of aluminum alloy material by die casting process. Its forming material can be ADC12, and its forming conditions are: mold temperature 220°C, material temperature 570-590°C; clamping force 350T, forming cycle 58 seconds.

[0064] After the main structure 101 is die-cast using a metal forming process, its sides can be further machined to obtain the side edge structure 102. Machining the sides serves two purposes: firstly, it removes the draft angle generated during die casting; secondly, it allows for precise external dimensions so that the structure can be inlaid into the inlay groove 203. Furthermore, it prepares the surface for subsequent laser welding.

[0065] For further information, please refer to [link / reference]. Figures 6 to 7 In one specific embodiment, a multi-station continuous rolling mill can be used to prepare several frame parts. The main processes include: rolling, annealing, leveling, and cutting. The rolling raw material is a large circular coil provided by an aluminum plant. After the operator loads the coil into the pre-set feeding tray of the multi-station rolling mill, it is rolled by multiple rollers and softened by intermediate annealing to form a rectangle with a cross-section of the required size, for example, a cross-sectional size of 12*4.0mm. After that, it is leveled and cut to the required length before being transferred to the next process for stamping.

[0066] Forming - Machining: Place the cut strip into the die to form the required shape, with the short side perpendicular to the long side; then place the formed product into the fixture of the machining center and process it to the required size, especially the inner welding groove, which must be precisely machined to facilitate the laser welding process with the middle plate in the next process.

[0067] Specifically, during rolling, the aluminum material used is AL6063, which is annealed and softened to HV50 after rolling, and then cut to the preset length. During bending, the forming conditions are: 80T press, forming time 6 seconds.

[0068] In summary, the manufacturing process for a mobile phone frame of the present invention involves first preparing a die-cast mid-plate, then preparing several frame parts, and then connecting the die-cast mid-plate to at least two frame parts using laser welding. After laser welding, the mid-plate-frame parts are machined to create injection molding grooves at predetermined positions on the die-cast mid-plate and frame parts. Next, the machined mid-plate-frame parts are subjected to in-mold injection molding. Finally, the workpiece is in-mold molded and then precision machined and surface treated to obtain the finished product. Using the process disclosed in this invention reduces costs by changing from all machining to partial machining, reducing machining volume by 70% and overall cost by 40%. Furthermore, it offers the advantage of stable quality because the welding method between the frame and mid-plate successfully solves the problem of anodizing and coloring die-cast aluminum, allowing for precise completion of each process with minimal machining. Additionally, this invention improves production efficiency, reducing the total processing time from 58 minutes to 37 minutes, increasing efficiency by 36%. Therefore, the manufacturing process of the mobile phone mid-frame of the present invention solves the technical problems of low-end products, limited process, high processing cost and unstable quality in the prior art.

[0069] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0070] The embodiments described above are merely illustrative of several implementations of the present invention, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the invention patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these all fall within the protection scope of the present invention. Therefore, the protection scope of this invention patent should be determined by the appended claims.

Claims

1. A manufacturing process of a mobile phone middle frame, characterized in that, It comprises the following steps: S1: preparing a middle plate die casting: first, using a metal die casting process to prepare a middle plate main structure, then machining the periphery of the middle plate main structure to remove the die casting draft angle and control the dimensional accuracy of the middle plate main structure to make it suitable for the subsequent welding process; S2: preparing a plurality of frame pieces respectively: using a rolling mill to roll the aluminum material roll to control the cross section of the aluminum material to meet the preset size requirement, then leveling and cutting to the preset length; Then, the cut strip-shaped piece is placed into a punch, and a stamping process is used to form a preset frame piece shape, so that the short side of each frame piece is perpendicular to the long side thereof; Then, the formed frame piece is placed into a fixture of a machining center, and CNC is used to process it to the required size; the shape and size of the inner side welding groove of each frame piece are processed to the preset accuracy by using the CNC process; After the stamping and CNC processes, at least two frame pieces are used to surround and connect the periphery of a middle plate die casting; S3: using a laser welding process to connect the middle plate die casting and at least two frame pieces: the middle plate die casting and all the frame pieces are simultaneously loaded into a welding fixture, and the positioning of the two is accurate; the laser welding machine is started, the laser beam is aligned with the position to be welded, and the middle plate die casting and the frame pieces around the periphery thereof are stably connected; S4: after the laser welding is completed, the middle plate-frame piece is machined to make the preset positions of the middle plate die casting and the frame piece into injection molding groove positions; S5: in-mold injection is performed on the machined middle plate-frame piece: first, a pretreatment process of degreasing and degreasing is used to thoroughly clean the part; then, T processing is used to generate micropores to facilitate the completion of the nano injection process; Nano injection is used to fill plastic at the preset positions of the middle plate-frame piece S6: mechanical finishing after in-mold injection molding: the in-mold injection part is placed into a fixture, accurately positioned, and a multi-axis machining center is used to process it in place at one time; Then, the outer surface of the middle frame is sandblasted and anodized for coloring to prepare a mobile phone middle plate product; The middle frame structure prepared by steps S1-S6 comprises a middle plate forming part, a frame forming part, and an auxiliary forming part; the periphery of the middle plate forming part is surrounded by at least two frame forming parts, and the inner side surface of each frame forming part is connected with the edge surface of the middle plate forming part; a plurality of auxiliary forming parts are distributed in the middle plate forming part, the inner side of the frame forming part, and between the middle plate forming part and the frame forming part; The middle plate forming part has a main structure and a side standing edge structure, and the periphery of the main structure is surrounded by the side standing edge structure; the frame forming part has at least two surrounding frames, an appearance modeling part, an inlay groove, and a welding part; the side standing edge structure is matched and connected with the inlay groove.

2. A middle frame structure facilitating molding using a manufacturing process of a middle frame of a mobile phone according to claim 1, characterized in that: All the surrounding frames are connected in sequence to form a ring. 3.The middle frame structure convenient for molding according to claim 2, characterized in that: The outer side of each surrounding frame is provided with the appearance modeling part, and the inner side of each surrounding frame is provided with the inlay groove and the welding part, and the inlay groove and the welding part are adjacent.

4. The middle frame structure convenient for molding according to claim 3, characterized in that: A surrounding frame is provided with a surrounding frame main body, an injection molding groove, and a socket part.

5. The middle frame structure convenient for molding according to claim 4, characterized in that: The plurality of injection grooves are evenly arranged in the surrounding frame body, and each of the plurality of socket portions is arranged through the surrounding frame body.

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