Injection mold, plastic frame and display device

Abstract

The application relates to an injection mold for forming a plastic frame for the side of a display module, comprising a first mold and a second mold, the first mold comprising a first mold core and a first mold frame covering the outside of the first mold core, and the second mold comprising a second mold core and a second mold frame covering the outside of the second mold core, the first mold core, the second mold core and the display module forming an injection cavity for forming the plastic frame; the first mold is provided with an inlet channel and an outlet channel, along the thickness direction of the first mold, the inlet channel comprises a first channel and a second channel connected in communication, and the end of the first channel away from the second channel is in communication with the injection cavity; the outlet channel comprises a third channel and a fourth channel connected in communication, and the end of the third channel away from the fourth channel is in communication with the injection cavity; the diameter of the first channel is larger than that of the third channel. The application also relates to a plastic frame and a display device.

Description

Technical Field

[0001] This invention relates to the field of display product manufacturing technology, and more particularly to an injection mold, a plastic frame, and a display device. Background Technology

[0002] Currently, AMOLED smartphones and wearables are all trending towards narrow bezels. Resin molding (injection molding) can significantly reduce bezels to achieve extremely narrow bezels. Resin molding involves low-pressure, room-temperature injection molding of the bezel onto the side of the display module, and then bonding the molded bezel to the main body of the device to achieve a narrow bezel. Because resin molding is low-pressure, room-temperature injection molding, and the molded bezel needs to provide structural support, air bubbles generated during the injection molding process can affect the overall strength of the assembled device. In actual manufacturing, the low-pressure, room-temperature injection molding method is prone to air bubble problems, which can impact the overall strength of the device. Summary of the Invention

[0003] To address the aforementioned technical problems, this invention provides an injection mold, a plastic frame, and a display device, which solve the problem of air bubbles generated during the injection molding process.

[0004] To achieve the above objectives, the technical solution adopted in this embodiment of the invention is: an injection mold for forming a plastic frame on the side of a display module, comprising a first mold and a second mold, the first mold comprising a first mold core and a first mold frame covering the outside of the first mold core, the second mold comprising a second mold core and a second mold frame covering the outside of the second mold core, the first mold core, the second mold core and the display module together forming an injection cavity for forming the plastic frame;

[0005] The first mold is provided with a glue inlet channel and a glue outlet channel. Along the thickness direction of the first mold, the glue inlet channel includes a first channel and a second channel that are connected. The end of the first channel away from the second channel is connected to the injection cavity.

[0006] The dispensing channel includes a third channel and a fourth channel that are connected to each other, and the end of the third channel away from the fourth channel is connected to the injection cavity;

[0007] The diameter of the first channel is larger than the diameter of the third channel.

[0008] Optionally, the diameter a of the first channel and the diameter b of the third channel satisfy the following formula: b≤1 / 2a.

[0009] Optionally, in the thickness direction of the first mold, the length of the first channel is 1 to 2 mm;

[0010] In the thickness direction of the first mold, the length of the third channel is 1 to 2 mm.

[0011] Optionally, the second channel is funnel-shaped, and the cross-sectional area of ​​the second channel at the end closest to the first channel is smaller than the cross-sectional area of ​​the second channel at the end furthest from the first channel.

[0012] The fourth channel is funnel-shaped, and the cross-sectional area of ​​the end of the fourth channel closer to the third channel is smaller than the cross-sectional area of ​​the end of the fourth channel farther from the third channel.

[0013] Optionally, the second channel is a columnar structure, the first surface of the second channel near the first channel is a planar structure, and the first surface is arranged perpendicular to the thickness direction of the first mold frame, and the first channel passes through the first surface and communicates with the second channel.

[0014] Optionally, the first mold frame has a first surface disposed away from the second mold frame, and the end of the second channel away from the first channel penetrates through the first surface and forms a first opening on the first surface, the diameter of the first opening being 4 to 8 mm.

[0015] Optionally, the plastic frame includes an annular main body area and two protrusions protruding from the inner side of the main body area, the two protrusions being spaced apart along the extending direction of the annular main body area;

[0016] The injection cavity includes a first cavity, and a second cavity and a third cavity communicating with the first cavity. The first cavity is configured to form the annular main body area, the second cavity is configured to form one lug, and the third cavity is configured to form another lug.

[0017] The first channel is connected to the second cavity, and the third channel is connected to the third cavity.

[0018] Optionally, in the thickness direction of the first mold, the depth of the second cavity is less than the depth of the first cavity, and the depth of the third cavity is less than the depth of the first cavity.

[0019] Optionally, the connection between the sidewall of the second cavity and the sidewall of the first cavity is rounded, and the radius of the rounded corner is 1 to 5 mm.

[0020] The connection between the sidewall of the third cavity and the sidewall of the first cavity is rounded, and the radius of the rounded corner is 1 to 5 mm.

[0021] Optionally, in the direction away from the first cavity, the length of the second cavity is greater than or equal to 2 mm;

[0022] In the direction away from the first cavity, the length of the third cavity is greater than or equal to 2 mm.

[0023] Optionally, the first cavity has a first sidewall disposed away from the second cavity and a second sidewall disposed away from the second mold frame, the first sidewall and the second sidewall being disposed adjacent to each other, and the included angle between the first sidewall and the second sidewall being an obtuse angle.

[0024] This invention also provides a plastic frame located on the side of the display module, formed by the aforementioned injection mold.

[0025] This invention also provides a display device, including a display module and the aforementioned plastic frame, wherein the plastic frame is located on the side of the display module.

[0026] The beneficial effects of the present invention are as follows: In the injection mold of the present invention, the first mold is provided with a glue inlet channel and a glue outlet channel. The glue inlet channel includes a first channel communicating with the injection cavity, and the glue outlet channel includes a third channel communicating with the injection cavity. The diameter of the first channel is larger than the diameter of the third channel. Reducing the diameter of the third channel allows the injection glue to accumulate locally at the third channel, thereby forming a larger pressure. The increased pressure at the third channel can compress the size of the air bubbles, playing a role in high-pressure bubble removal. At the same time, because the direction of injection glue flow is from the first channel into the injection cavity and then to the third channel, under this high-pressure condition, the air bubbles can be quickly expelled to the outside. Attached Figure Description

[0027] Figure 1 This diagram illustrates the structure of the injection mold in an embodiment of the present invention. Figure 1 ;

[0028] Figure 2 This diagram illustrates the structure of the injection mold in an embodiment of the present invention. Figure 2 ;

[0029] Figure 3 This diagram illustrates the structure of the injection mold in an embodiment of the present invention. Figure 3 ;

[0030] Figure 4 A schematic diagram showing that a plastic frame is formed around the display module in an embodiment of the present invention;

[0031] Figure 5 express Figure 4 Enlarged view of a part Figure 1 ;

[0032] Figure 6 express Figure 4 Enlarged view of a part Figure 2 ;

[0033] Figure 7 A partial schematic diagram of the plastic frame.

[0034] 11 First mold base; 12 First mold core; 21 Second mold base; 22 Second mold core; 1322 First opening; 13 Inlet channel; 131 First channel; 132 Second channel; 32 Second cavity; 31 First cavity; 32 Second cavity; 33 Third cavity; 14 Outlet channel; 141 Third channel; 142 Fourth channel; 1421 Second opening; 301 First side wall; 302 Second side wall; 5 Inlet head; 1321 First surface; 101 Plastic frame; 100 Display module; 102 First lug; 103 Second lug; 1022 First rounded corner; 1032 Second rounded corner; 1001 First side surface; 1002 Second side surface; 104 Annular main body area. Detailed Implementation

[0035] To make the objectives, technical solutions, and advantages of the embodiments of this disclosure clearer, the technical solutions of the embodiments of this disclosure will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this disclosure. All other embodiments obtained by those skilled in the art based on the described embodiments of this disclosure without creative effort are within the scope of protection of this disclosure.

[0036] Unless otherwise defined, the technical or scientific terms used in this disclosure shall have the ordinary meaning understood by one of ordinary skill in the art to which this disclosure pertains. The terms “first,” “second,” and similar terms used in this disclosure do not indicate any order, quantity, or importance, but are merely used to distinguish different components. Similarly, the terms “an,” “a,” or “the,” and similar terms do not indicate a quantity limitation, but rather indicate the presence of at least one. The terms “including,” “comprising,” or “containing,” and similar terms mean that the element or object preceding the word encompasses the elements or objects listed following the word and their equivalents, without excluding other elements or objects. The terms “connected,” “linked,” or similar terms are not limited to physical or mechanical connections, but can include electrical connections, whether direct or indirect. The terms “upper,” “lower,” “left,” and “right,” etc., are used only to indicate relative positional relationships, and these relative positional relationships may change accordingly when the absolute position of the described objects changes.

[0037] In related technologies, the Resin Molding process involves placing the display module in a specially designed fixture at room temperature and low pressure. This fixture includes inlet and outlet ports and a parting line. The adhesive is injected through the inlet port, then splits into two parts that move towards the outlet port, finally merging at the outlet port (e.g., ...). Figure 1As shown, maintaining low pressure within the injection cavity minimizes air accumulation during glue dispensing, but some residual air remains in the runner, easily forming bubbles when the glue merges. Conventional injection molding methods to improve bubble removal include: ① adding vents to the outside of the nozzle and its location; ② using high temperature and pressure to compress and remove gas from the runner area. However, because the Resin Molding process does not allow for venting structures in this location, and high temperatures can damage OLED (Organic Light Emitting Diode) MDL (Display Module), alternative solutions are needed to address the nozzle bubble problem.

[0038] refer to Figures 1-6 To address the aforementioned issues, this embodiment provides an injection mold for forming a plastic frame 101 on the side of a display module 100. The mold includes a first mold and a second mold. The first mold includes a first mold core 12 and a first mold frame 11 covering the outside of the first mold core 12. The second mold includes a second mold core 22 and a second mold frame 21 covering the outside of the second mold core 22. The first mold core 12, the second mold core 22, and the display module 100 together form an injection cavity for forming the plastic frame 101.

[0039] The first mold is provided with a glue inlet channel 13 and a glue outlet channel 14, along the thickness direction of the first mold (reference). Figure 1 (in the X direction), the glue inlet channel 13 includes a first channel 131 and a second channel 132 that are connected to each other, and the end of the first channel 131 away from the second channel 132 is connected to the injection cavity;

[0040] The dispensing channel 14 includes a third channel 141 and a fourth channel 142 that are connected to each other. The end of the third channel 141 that is away from the fourth channel 142 is connected to the injection cavity.

[0041] The diameter a of the first channel 131 is greater than the diameter b of the third channel 141.

[0042] In related technologies, the injection cavity is annular, and the diameter 'a' of the first channel 131 and the diameter 'b' of the third channel 141 are the same. The injection molding compound undergoes vacuum degassing pretreatment and is then filled using a vacuum dispensing machine. The injection molding compound passes through the first channel 131 and then enters the injection cavity from both sides. At this point, the injection molding compound experiences minimal changes within the cavity, maintaining a relatively stable and consistent velocity. The injection molding compound is in a laminar flow state, with its particles moving smoothly in a straight line along a direction parallel to the tube axis (i.e., the extension direction of the injection cavity). The flow velocity of the injection molding compound is highest at the center of the cavity and lowest near the wall. In this laminar flow state, the injection molding compound is less prone to bubble formation within the cavity and simultaneously pushes any remaining bubbles forward to the third channel 141. When the injection molding compound from both sides converges in the third channel 141, the air in the cavity cannot be expelled in time, leading to the formation of bubbles nearby.

[0043] In this embodiment, the diameter a of the first channel 131 is larger than the diameter b of the third channel 141. This allows the injection molding compound to accumulate locally in the third channel 141, thereby creating greater pressure. The increased pressure in the third channel 141 can compress the size of the bubbles, achieving the effect of high-pressure bubble removal. At the same time, since the injection molding compound flows from the first channel 131 to the third channel 141, under this high-pressure condition, the bubbles can be quickly expelled to the outside.

[0044] In an exemplary embodiment, the diameter a of the first channel 131 and the diameter b of the third channel 141 satisfy the following formula: 1 / 5a≤b≤1 / 2a.

[0045] By comparison and verification, the smaller the diameter b of the third channel 141, the better the bubble removal ability, as shown in Table 1 below (where b is the diameter of the third channel 141 and a is the diameter a of the first channel 131). However, if the diameter b of the third channel 141 is too small, it will cause blockage of the injection molding compound and affect the injection molding quality. Therefore, in some embodiments, the value of b is selected as follows: 1 / 5a ≤ b ≤ 1 / 2a. For example, b can be 1 / 5a, 1 / 4a, 1 / 3a, or 1 / 2a.

[0046] In some specific embodiments, the diameter b of the third channel 141 is 1 / 2a. At this point, the bubble defect rate meets the preset requirements and will not cause the injection molding compound to clog, but this is not a limitation.

[0047] Table 1

[0048] b = a b = 7 / 10a b = 1 / 2a B = 3 / 10a Sample quantity 400 400 400 330 Samples with poor bubble quality 184 80 2 1 Bubble defect rate 46％ 20％ 0.5％ 0.3％

[0049] It should be noted that the injection molding compound used to form the plastic frame 101 is generally a low-temperature epoxy resin with a viscosity of 10,000–40,000 cps. The width of the main body area of ​​the injection cavity is generally 1 mm. If the diameter 'a' of the first channel 131 is too large, it will cause a large sudden pressure change when the colloid enters the injection cavity, resulting in initial air bubbles. If the diameter 'a' of the first channel 131 is too small, it will affect the flow rate of the injection molding compound and reduce the injection molding efficiency. Therefore, in some specific embodiments, the diameter 'a' of the first channel 131 is 0.8–2 mm, for example, 'a' can be 0.8 mm, 1 mm, 1.3 mm, 1.7 mm, or 2 mm.

[0050] In order to allow air bubbles in the injection cavity to be expelled quickly, the diameter b of the third channel 141 is smaller than the diameter a of the first channel 131. Therefore, corresponding to the selection of the value of a, the diameter b of the third channel 141 is 0.4 to 1 mm. For example, b can be 0.4 mm, 0.6 mm, 0.8 mm, or 1 mm, but is not limited to this.

[0051] In some embodiments, the first channel 131 and the third channel 141 are both cylindrical structures, which allows the injection molding compound to smoothly enter the injection cavity, but this is not a limitation.

[0052] In an exemplary embodiment, in the thickness direction of the first mold (refer to...) Figure 1 (in the X direction), the length of the first channel 131 is 1 to 2 mm, for example, the length of the first channel 131 can be 1 mm, 1.5 mm, 1.8 mm, or 2 mm;

[0053] In the thickness direction of the first mold, the length of the third channel 141 is 1 to 2 mm. For example, the length of the third channel 141 can be 1 mm, 1.5 mm, 1.8 mm, or 2 mm.

[0054] In an exemplary embodiment, the second channel 132 is in the thickness direction of the first mold (refer to...). Figure 1 The cross-sectional shape in the X direction is trapezoidal, and the cross-sectional area of ​​the second channel 132 at the end closer to the first channel 131 is smaller than the cross-sectional area of ​​the second channel 132 at the end farther from the first channel 131. For example, the second channel 132 is funnel-shaped to facilitate the injection of injection molding compound.

[0055] The fourth channel 142 is parallel to the thickness direction of the first mold (reference). Figure 1The cross-sectional shape in the X direction is trapezoidal, and the cross-sectional area of ​​the end of the fourth channel 142 near the third channel 141 is smaller than the cross-sectional area of ​​the end of the fourth channel 142 away from the third channel 141. For example, the fourth channel 142 is funnel-shaped as a whole.

[0056] The second channel 132 is funnel-shaped, which facilitates the injection of injection molding compound and allows the first channel 131 to have a suitable cross-sectional area, that is, the first channel 131 to have a suitable diameter.

[0057] The fourth channel 142 is funnel-shaped, which buffers the speed of the outflowing injection molding compound and prevents it from splashing everywhere.

[0058] In the embodiment where the second channel 132 is funnel-shaped, the injection head is funnel-shaped and conforms to the shape of the second channel 132. The injection head and the first mold form a seal by contacting each other at the injection starting point through an inclined surface. Due to the inclined surface design, in order to ensure a complete seal between the injection head and the second channel 132, the contact pressure between the injection head and the second channel 132 needs to be large enough. However, if the pressure is too high, there will be a problem of deformation of the injection head and the second channel 132, which will affect the life of the injection mold.

[0059] refer to Figure 3 To address the aforementioned issues, in other embodiments of this example, the second channel 132 is configured as a columnar structure, and the first surface 1321 of the second channel 132 near the first channel 131 is a planar structure, with the first surface 1321 perpendicular to the thickness direction of the first mold frame 11 (see reference). Figure 1 The first channel 131 is positioned in the X direction, penetrating the first surface 1321 and communicating with the second channel 132. The inlet head 5 is a columnar structure that matches the shape of the second channel 132. The inlet head 5 and the injection mold form a seal at the injection starting point through planar contact. The pressure between the planar inlet head 5 and the second channel 132 does not need to be too high, while the contact area of ​​the planar surface is larger, thus increasing the contact area between the inlet head 5 and the second channel 132. This effectively improves the lifespan of the injection mold and the sealing capability of the second channel 132.

[0060] For example, the injection head 5 has an injection port that can be inserted into the first channel 131, which facilitates the injection of injection molding compound and the sealing between the injection head 5 and the injection mold.

[0061] In an exemplary embodiment, the first mold base 11 has a first surface disposed away from the second mold base 21. One end of the second channel 132, away from the first channel 131, penetrates the first surface and forms a first opening 1322 on the first surface. The diameter e of the first opening 1322 is 4–8 mm. For example, the diameter e of the first opening 1322 can be 4 mm, 5 mm, 6 mm, 7 mm, or 8 mm. (Refer to...) Figure 1 .

[0062] The first mold frame 11 has a first surface located away from the second mold frame 21. The fourth channel 142 extends through the first surface at one end away from the third channel 141 and forms a second opening 1421 on the first surface. The diameter of the second opening 1421 is 4 to 8 mm. For example, the diameter of the second opening 1421 can be 4 mm, 5 mm, 6 mm, 7 mm, or 8 mm.

[0063] The diameter of the first opening 1322 is 4-8 mm, and the diameter of the second opening 1421 is 4-8 mm. This facilitates cooperation with the injection nozzle that provides injection molding compound, so as to smoothly inject the injection molding compound into the injection cavity.

[0064] refer to Figure 4 In an exemplary embodiment, the plastic frame 101 includes an annular main body area and two protrusions (a first protrusion 102 and a second protrusion 103) protruding from the inner side of the main body area, the two protrusions being spaced apart along the extending direction of the annular main body area;

[0065] The injection cavity includes a first cavity 31, and a second cavity 32 and a third cavity 33 communicating with the first cavity 31. The first cavity 31 is configured to form the annular main body area, the second cavity 32 is configured to form one lug, and the third cavity 33 is configured to form another lug.

[0066] The first channel 131 is connected to the second cavity 32, and the third channel 141 is connected to the third cavity 33.

[0067] In this embodiment, the injection-molded plastic frame 101 wraps around the display module 100, and its edge is flush with the edge of the cover plate of the display module 100. The first cavity 31 is annular, and the second cavity 32 and the third cavity 33 are both located inside the first cavity 31. Therefore, the lug after injection molding is formed inside the annular main body area, ensuring that there are no injection molding joint marks on the outside of the molded main body (i.e., the whole of the plastic frame), which facilitates the assembly of the whole machine.

[0068] The first cavity 31 extends into an annular shape, and the injection channel 13 and the outlet channel 14 are arranged radially opposite to each other along the first cavity 31. This ensures that there is sufficient distance between the injection channel 13 and the outlet channel 14, which facilitates the filling of the first cavity 31, the second cavity 32, and the third cavity 33 with injection molding glue, thereby improving the injection molding yield and simplifying operation.

[0069] In an exemplary embodiment, in the thickness direction of the first mold (refer to...) Figure 1 In the X direction), the depth of the second cavity 32 is less than the depth of the first cavity 31, and the depth of the third cavity 33 is less than the depth of the first cavity 31.

[0070] By adopting the above solution, the thickness of the lug after injection molding is less than the thickness of the annular main body area, thus avoiding affecting the assembly of the whole machine.

[0071] In an exemplary embodiment, the depth of the second cavity 32 is greater than or equal to 0.2 mm. For example, the depth of the second cavity 32 can be 0.2 mm, 0.25 mm, 0.3 mm, 0.35 mm, or 0.4 mm. The depth of the third cavity 33 is greater than or equal to 0.2 mm. For example, the depth of the third cavity 33 can be 0.2 mm, 0.25 mm, 0.3 mm, 0.35 mm, or 0.4 mm. This ensures that there is sufficient space for the injection molding material to buffer during the injection molding process, so that the liquid flowing into the first cavity 31 is at a uniform speed without sudden changes in speed, thereby reducing the generation of air bubbles in the first cavity 31.

[0072] In an exemplary embodiment, the connection between the sidewall of the second cavity 32 and the sidewall of the first cavity 31 is rounded, and the radius of the rounded corner is 1 to 5 mm. For example, the radius of the rounded corner can be 1 mm, 2 mm, 3 mm, 4 mm, or 5 mm.

[0073] The connection between the sidewall of the third cavity 33 and the sidewall of the first cavity 31 is rounded, and the radius of the rounded corner is 1 to 5 mm. For example, the radius of the rounded corner can be 1 mm, 2 mm, 3 mm, 4 mm, or 5 mm.

[0074] Figure 5 The image shows the first rounded corner 1022 formed between the first lug 102 and the annular main body area. Figure 6 The second rounded corner 1032 formed between the second lug 103 and the annular main body area is shown. Referring to Table 2 below, the larger the rounded corner half-angle R value (i.e. the radius value of the rounded corner between the lug of the injection-molded plastic frame and the annular main body area), the better the bubble defect rate. After the R value is changed from 0.2mm to 1mm, the bubble defect at the glue outlet channel is improved by about 3% to 5%.

[0075] Table 2

[0076] Corner radius R (mm) 0.2 1 2 Sample quantity 1000 1000 100 Samples with poor bubble quality 88 54 3 Bubble defect rate 8.80％ 5.40％ 3.00％

[0077] The R-value can be as large as possible, ranging from 1 to 5 mm, provided the structural requirements are met. Simultaneously, a larger R-value results in larger chamfers in the injection mold (i.e., the fillet between the sidewall of the second cavity and the sidewall of the first cavity, and the fillet between the sidewall of the third cavity and the sidewall of the first cavity). This makes demolding easier after the injection molding compound has cured, effectively extending the mold's lifespan.

[0078] In an exemplary embodiment, in the direction away from the first cavity 31 (refer to...) Figure 1 In the Y direction of the first cavity 31, the length of the second cavity 32 is greater than or equal to 2 mm. For example, the length of the second cavity can be 1 mm, 2 mm, 3 mm, 4 mm, or 5 mm. In the direction away from the first cavity 31, the length of the third cavity 33 is greater than or equal to 2 mm. For example, the length of the third cavity 33 can be 1 mm, 2 mm, 3 mm, 4 mm, or 5 mm. Figure 6 The length h of the second lug 103 is shown, where h is the length of the lug and the minimum value of h is 2mm.

[0079] It should be noted that when the h value is larger, the third cavity 33 can accommodate more air bubbles. The air bubbles in the first cavity 31 will all flow into the third cavity 33, and the air bubbles in the third cavity 33 will be effectively discharged through the adhesive outlet channel 14. Since the second lug 103 formed by the third cavity 33 is too large and will interfere with the display module MFPC (main flexible circuit board), the reasonable range for the diameter of the lug (i.e., the third cavity 33) is 2-5 mm. For example, the diameter of the lug can be 2 mm, 3 mm, 4 mm, or 5 mm.

[0080] For example, the length of the second cavity 32 is the same as the length of the third cavity 33, but this is not a limitation.

[0081] For example, the second cavity 32 and the third cavity 33 have the same structure. The shape of the second cavity 32 can be various, such as rectangular or trapezoidal, in order to maximize the volume of the second cavity 32 or the third cavity 33 as much as possible.

[0082] In an exemplary implementation, reference is made to Figure 1 and Figure 2The first cavity 31 has a first sidewall 301 disposed away from the second cavity 32 and a second sidewall 302 disposed away from the second mold frame 21. The first sidewall 301 and the second sidewall 302 are disposed adjacent to each other, and the included angle θ between the first sidewall 301 and the second sidewall 302 is an obtuse angle.

[0083] For example, the included angle θ between the first sidewall 301 and the second sidewall 302 is 100-120 degrees, for example, it can be 100 degrees, 105 degrees, 110 degrees, 115 degrees, or 120 degrees, but is not limited thereto.

[0084] In related technologies, the included angle between the first sidewall 301 and the second sidewall 302 is 90 degrees. During injection molding, due to the high viscosity of the adhesive and the roughness of the surface of the first mold core, it is difficult for the adhesive to completely fill the right-angled area between the first sidewall 301 and the second sidewall 302. After the injection molding compound cures, white edges caused by air bubbles or through-holes will appear on the side of the annular main body area. To address this problem, in this embodiment, the included angle between the first sidewall 301 and the second sidewall 302 is set to an obtuse angle, so that the injection molding compound can completely fill the corner area between the first sidewall 301 and the second sidewall 302, thus solving the problem of white edges forming on the sidewalls of the annular main body area of ​​the plastic frame.

[0085] refer to Figures 4-6 The present invention also provides a plastic frame 101 located on the side of the display module 100, which is formed by the above-mentioned injection mold.

[0086] The plastic frame 101 includes an annular main body area and two lugs located inside the annular main body area. The two lugs include a first lug 102 and a second lug 103. The annular main body area is formed by a first cavity in the injection mold, the first lug 102 is formed by a second cavity, and the second lug is formed by a third cavity.

[0087] The first lug 102 and the second lug 103 are arranged opposite each other in the radial direction of the annular main body region.

[0088] refer to Figure 7 The thickness of the first lug 102 is less than the thickness of the annular main body region 104, and the thickness of the second lug 103 is less than the thickness of the annular main body region 104, thereby avoiding assembly interference.

[0089] In the radial direction of the annular main body area 104, the annular main body area 104 includes a first side surface 1001 away from the lug and a second side surface 1002 adjacent to the first side surface 1001. The second side surface 1002 is located on the side away from the display module. The first side surface 1001 is inclined such that the included angle α between the first side surface 1001 and the second side surface 1002 is an obtuse angle.

[0090] For example, the included angle α between the first side 1001 and the second side 1002 is 100-120 degrees, for example, it can be 100 degrees, 105 degrees, 110 degrees, 115 degrees, or 120 degrees, but is not limited thereto.

[0091] In an exemplary embodiment, in the direction perpendicular to the thickness of the display module (refer to...) Figure 7 In the X direction of the injection mold, the length f of the first lug 102 is greater than or equal to 2a, where a is the diameter of the first channel of the injection mold's injection channel. Figure 1 .

[0092] In the direction perpendicular to the thickness of the display module, the length f of the second lug 103 is ≥ 2a. The longer the length of the first lug 102, the more space the injection molding material has to be buffered, allowing the injection molding material entering the second cavity to advance at a uniform speed and avoiding the formation of air bubbles. The longer the length of the second lug 103, the more effectively all air bubbles in the injection cavity are directed into the third cavity and formed within the second lug 103, ensuring that there are no air bubbles in the annular main body area and improving product yield. However, if the length of the first lug 102 or the second lug 103 is too large, it will interfere with the main flexible circuit board of the display module. Therefore, f ≤ 4a. In some embodiments, the length f of the first lug 102 is 2 to 5 mm, for example, the value of f can be 2 mm, 3 mm, 4 mm, or 5 mm (the length of the second lug 103 is the same as the length of the first lug 102).

[0093] This invention also provides a display device, including a display module and the aforementioned plastic frame, wherein the plastic frame is located on the side of the display module.

[0094] The display device can be any product or component with display function, such as a digital photo frame, mobile phone, or tablet computer. The display device also includes a flexible circuit board, a printed circuit board, and a backplate.

[0095] It is understood that the above embodiments are merely exemplary implementations used to illustrate the principles of the present invention, and the present invention is not limited thereto. For those skilled in the art, various modifications and improvements can be made without departing from the spirit and essence of the present invention, and these modifications and improvements are also considered to be within the scope of protection of the present invention.

Claims

1. An injection mold for forming a plastic frame for the side of a display module, comprising a first mold and a second mold, the first mold comprising a first mold core and a first mold frame covering the outside of the first mold core, the second mold comprising a second mold core and a second mold frame covering the outside of the second mold core, the first mold core, the second mold core, and the display module forming an injection cavity for forming the plastic frame; characterized in that, The first mold is provided with a glue inlet channel and a glue outlet channel. Along the thickness direction of the first mold, the glue inlet channel includes a first channel and a second channel that are connected. The end of the first channel away from the second channel is connected to the injection cavity. The dispensing channel includes a third channel and a fourth channel that are connected to each other, and the end of the third channel away from the fourth channel is connected to the injection cavity; The diameter of the first channel is larger than the diameter of the third channel; The diameter 'a' of the first channel and the diameter 'b' of the third channel satisfy the following formula: b ≤ 1 / 2a; The plastic frame includes an annular main body area and two protruding lugs protruding from the inner side of the annular main body area, the two protruding lugs being spaced apart along the extending direction of the annular main body area; The injection cavity includes a first cavity, and a second cavity and a third cavity communicating with the first cavity. The first cavity is configured to form the annular main body area, the second cavity is configured to form one lug, and the third cavity is configured to form another lug. The first channel is connected to the second cavity, and the third channel is connected to the third cavity; The connection between the sidewall of the second cavity and the sidewall of the first cavity is rounded, and the radius of the rounded corner is 1~5mm; The connection between the sidewall of the third cavity and the sidewall of the first cavity is rounded, and the radius of the rounded corner is 1~5mm.

2. The injection mold according to claim 1, characterized in that, In the thickness direction of the first mold, the length of the first channel is 1~2mm; In the thickness direction of the first mold, the length of the third channel is 1~2mm.

3. The injection mold according to claim 1, characterized in that, The second channel is funnel-shaped, and the cross-sectional area of ​​the second channel at the end closest to the first channel is smaller than the cross-sectional area of ​​the second channel at the end furthest from the first channel; The fourth channel is funnel-shaped, and the cross-sectional area of ​​the end of the fourth channel closer to the third channel is smaller than the cross-sectional area of ​​the end of the fourth channel farther from the third channel.

4. The injection mold according to claim 1, characterized in that, The second channel has a columnar structure, and the first surface of the second channel near the first channel has a planar structure. The first surface is perpendicular to the thickness direction of the first mold frame, and the first channel passes through the first surface and communicates with the second channel.

5. The injection mold according to claim 1, characterized in that, The first mold frame has a first surface located away from the second mold frame. The end of the second channel away from the first channel passes through the first surface and forms a first opening on the first surface. The diameter of the first opening is 4~8mm.

6. The injection mold according to claim 1, characterized in that, In the thickness direction of the first mold, the depth of the second cavity is less than the depth of the first cavity, and the depth of the third cavity is less than the depth of the first cavity.

7. The injection mold according to claim 1, characterized in that, In the direction away from the first cavity, the length of the second cavity is greater than or equal to 2 mm; In the direction away from the first cavity, the length of the third cavity is greater than or equal to 2 mm.

8. The injection mold according to claim 1, characterized in that, The first cavity has a first sidewall disposed away from the second cavity and a second sidewall disposed away from the second mold frame. The first sidewall and the second sidewall are disposed adjacent to each other, and the included angle between the first sidewall and the second sidewall is an obtuse angle.

9. A plastic frame located on the side of a display module, characterized in that, Formed using an injection mold as described in any one of claims 1-8.

10. A display device, characterized in that, It includes a display module and a plastic frame as described in claim 9, the plastic frame being located on the side of the display module.

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