Composite deep frame shell nanoinjection molding manufacturing process and composite deep frame shell

Abstract

The application relates to the technical field of injection molding, in particular to a composite deep-frame shell nano-injection manufacturing process and a composite deep-frame shell. The composite deep-frame shell nano-injection manufacturing process comprises the following steps: S1, stamping, stamping a metal plate to obtain an outer shell; S2, chemical treatment, treating the inner surface of the outer shell by using treatment liquid to form nano-level holes; S3, preheating, placing the outer shell into a mold and preheating the outer shell through the mold; S4, injection molding, injection molding on the inner surface of the outer shell to obtain an inner shell; S5, demolding, taking the outer shell out of the mold; S6, polishing, polishing and wire drawing of the outer shell; and S7, cleaning, ultrasonic cleaning of the outer shell. The outer shell is obtained through stamping, and the obtained outer shell has high strength. The post-processing procedures of surface polishing and wire drawing and ultrasonic cleaning can not only guarantee the appearance of the outer shell, but also can save the long-time high-temperature baking procedure in the traditional nano-injection process, so that the production efficiency is greatly improved.

Description

Technical Field

[0001] This invention relates to the field of mining shell technology, and in particular to a nano-injection molding manufacturing process for composite deep frame shells and the composite deep frame shell itself. Background Technology

[0002] Mining electronic equipment operates in harsh environments, and the complex underground coal mine environment poses challenges to the IP protection, strength, and electromagnetic shielding performance of the electronic equipment enclosure. In addition, GB / T 3836-2021 also imposes stringent testing requirements on the enclosures of equipment in explosive environments, including impact resistance, drop resistance, flame retardancy, heat resistance, cold resistance, and high and low temperature impact.

[0003] Mining metal casings are generally made of stainless steel using welding or stretching processes. However, the internal waterproof sealing structure and the installation studs exhibit poor consistency in manufacturing processes, making it difficult to guarantee protective performance. Furthermore, to meet strength requirements, metal casings need to maintain a certain wall thickness, resulting in significant weight. Mining plastic casings suffer from drawbacks such as low structural strength, poor electromagnetic shielding performance, and the need for flame-retardant modification. With increasingly stringent requirements for the stability of mining equipment in coal mine safety production, there is an urgent need for a composite waterproof casing suitable for mining electronic equipment that combines advantages such as strength, protection, lightweight, good consistency, stability, reliability, and strong environmental adaptability.

[0004] Nano-injection molding is a new technology that achieves a strong bond between plastic and metal. Injection molding requires the use of a T-process to form nanoscale pores on the metal surface, and then plastic is injected into the nanopores, using the anchoring effect to achieve the plastic-metal bond.

[0005] Nano-injection molding requires nanoscale plastics to possess high fluidity and low shrinkage. Injection conditions involve high mold temperature and high pressure. Metal parts must be preheated before injection to ensure the molded material can quickly fill the nanopores before cooling. Furthermore, pre-processed stretching structures must be provided on the metal parts to enhance the bond between the plastic and metal. After injection molding, the product requires prolonged annealing and baking to eliminate internal stresses between the metal and plastic. In summary, nano-injection molding is complex, involves numerous steps, and is costly, hindering its widespread adoption.

[0006] Currently, nano-injection molding technology is mainly used in planar thin-walled structures such as lithium battery covers and mobile phone casings. These products require small injection volumes, and injection shrinkage is limited to a two-dimensional direction. The bonding between metal and plastic is enhanced through a stretching structure, making the molding process relatively simple. However, the structure of large, deep-frame waterproof casings is more complex. In addition to the simple molding of mounting studs, complex sealing and protective structures are required, resulting in a more complex overall process and lower efficiency. Summary of the Invention

[0007] To address the technical problems in the prior art, this invention provides a nano-injection molding manufacturing process for composite deep frame shells and a composite deep frame shell.

[0008] The technical solution adopted by this invention to solve its technical problem is: a nano-injection molding manufacturing process for composite deep frame shells, wherein the deep frame shell includes an outer shell and an inner shell injection molded within the outer shell. The nano-injection molding manufacturing process for composite deep frame shells includes the following steps:

[0009] S1. Stamping: Stamping a metal sheet to obtain the outer shell;

[0010] S2. Chemical treatment: The inner surface of the outer shell is treated with a chemical solution to form nanoscale pores.

[0011] S3. Preheating: Place the outer shell into the mold and preheat it through the mold;

[0012] S4. Injection molding: Injection molding is performed on the inner surface of the outer shell to obtain the inner shell.

[0013] S5. Demolding: Remove the outer shell from the mold.

[0014] S6. Polishing: Polishing and brushing the outer casing;

[0015] S7. Cleaning: Perform ultrasonic cleaning on the outer casing.

[0016] The above technical solution allows for direct stamping of the outer shell, resulting in high production efficiency and high strength. Chemical treatment creates nanoscale pores on the inner surface of the outer shell, facilitating better bonding between the plastic and the shell during injection molding. After the inner shell cools and is formed, it undergoes surface brushing and polishing, followed by ultrasonic cleaning in warm water. During the brushing and polishing process, localized instantaneous high temperatures on the outer surface of the outer shell are conducted to the nanoscale pores on the inner wall without affecting the plastic body of the inner shell. These localized instantaneous high temperatures help eliminate surface stress between the metal substrate and the plastic. After brushing and polishing, ultrasonic cleaning in warm water is performed. The ultrasonic vibrations during ultrasonic cleaning increase the crystallinity of the nanoscale crystalline plastic (PBT or PPS), improving its dimensional stability. These post-processing steps of surface polishing, brushing, and ultrasonic cleaning ensure the appearance of the outer shell and eliminate the need for prolonged high-temperature baking in traditional nano-injection molding processes, significantly improving production efficiency.

[0017] Furthermore, the inner shell is provided with rounded corners. During injection molding, the injection port is located at the rounded corners, and each rounded corner corresponds to one injection port. After the inner shell is formed, the injection port is cut off.

[0018] By employing the aforementioned technical solution, the injection gate is positioned near the rounded corners, enhancing the bonding strength between the rounded corners and the outer shell, and helping to resist the shrinkage stress transmitted from the inner shell sidewalls. Nano-injection molding requires high plastic flowability to ensure the injection-molded material rapidly fills the nano-voids before cooling. Because the plastic at the injection gate has just entered the outer shell and has not yet been cooled by the mold temperature, its flowability is stronger, resulting in better bonding strength at the gate. Furthermore, the multiple rounded corners and multiple injection gates reduce filling and plastic cooling time, improving plastic flowability and bonding strength.

[0019] Furthermore, during injection molding, the mold is provided with a limiting rod, which is arranged along the circumference of the outer shell on the end face of the outer shell, and the limiting rod is suitable for limiting the outer shell.

[0020] With the above technical solution, during nano-injection molding, the outer shell needs to be placed in the mold before injection molding; positional deviations can lead to injection separation problems. The limiting rods, arranged circumferentially on the end face of the outer shell, can ensure the positioning accuracy between the outer shell and the inner shell as much as possible. The limiting rods also help with venting, preventing air trapping within the nanopores and enhancing the bonding strength.

[0021] Furthermore, during injection molding, the mold is provided with an ejector rod, which is arranged circumferentially on the end face of the outer shell and is adapted to eject the outer shell from the mold.

[0022] Through the above technical solution, the ejector rod can assist in supporting the outer shell, further improving the positioning accuracy between the outer shell and the inner shell. At the same time, it facilitates the ejection of the injection-molded outer shell from the mold. In addition, the ejector rod can also help vent air, avoid air entrapment in the nanopores, and enhance the bonding strength.

[0023] Furthermore, after the outer shell is demolded, both the outer and inner shells are subjected to uniform temperature shaping.

[0024] Furthermore, after the outer shell is demolded, it is subjected to uniform temperature shaping by a uniform temperature cooling and shaping fixture. The uniform temperature cooling and shaping fixture includes a uniform temperature inner core and a uniform temperature cover. The uniform temperature inner core is inserted into the inner shell and fits snugly against the inner shell. The uniform temperature cover is in hard contact with the bottom surface of the main shell and is connected to the uniform temperature inner core by bolts.

[0025] Through the above technical solution, after the outer shell and inner shell are demolded, the overall temperature is relatively high. During the cooling process, the outer shell, being metal, has good thermal conductivity and a large contact area with air, thus cooling quickly. The inner shell, being plastic, has poor thermal conductivity and a small contact area with air, thus cooling slowly. Simultaneously, the inner shell sidewalls with a smaller plastic volume cool quickly, while the rounded corners with a larger plastic volume cool slowly. This difference in cooling rate leads to a difference in shrinkage, causing overall concave deformation of the shell and exacerbating the shrinkage force at the rounded corners. Therefore, after the inner shell is fitted with the temperature-regulating inner core, bolts are used to fix the temperature-regulating inner core, outer shell, and temperature-regulating cover together. The temperature-regulating inner core accelerates the cooling of the inner shell, thereby ensuring that the cooling rates of the outer and inner shells are consistent and reducing shrinkage stress. Furthermore, the temperature-regulating shaping fixture also ensures the overall dimensional stability of the outer and inner shells and provides support.

[0026] Secondly, the present invention discloses a composite deep frame shell.

[0027] A composite deep-frame housing includes an outer shell; an inner shell, which is injection-molded into the outer shell and has rounded corners; an arc-shaped support portion, which is recessed and corresponds to the rounded corners of the inner shell; a reinforcing bottom plate, which is connected to both the bottom surface of the arc-shaped support portion and the bottom surface of the outer shell, but not to the inner shell; an inner support plate, which is located between the arc-shaped support portion and the inner shell, at the bottom of the arc-shaped support portion, and is connected to the inner shell, the arc-shaped support portion, and the outer shell; and a capping stud is connected to the inner support plate, the capping stud having a... The first embedded nut is adapted to be connected to the cover plate; the cover stud and the arc support are connected by reinforcing ribs; the reinforcing ribs are arranged in pairs; the side of the reinforcing base plate is provided with an ejector portion, which is connected to the bottom surface of the outer shell; the end face of the inner shell is provided with a waterproof rib, which is arranged around the circumference of the inner shell and is in a closed state, and the waterproof rib is adapted to cooperate with the cover plate; the reinforcing base plate is provided with an injection-molded nut portion, and the injection-molded nut portion is provided with a second embedded nut, which is in hard contact with the inner bottom surface of the outer shell, and the second embedded nut is adapted to be connected to the circuit board.

[0028] Through the above technical solution, the arc-shaped support portion can support the inner shell, helping the rounded corners resist the contraction force transmitted from the sidewalls of the inner shell. The bonding force between the reinforcing base and the bottom surface of the outer shell works in conjunction with the arc-shaped support portion, distributing the force along the height direction to the rounded corners, further resisting the contraction force transmitted from the sidewalls of the inner shell. Simultaneously, the reinforcing base is not connected to the inner shell, preventing the transfer of its own contraction stress to the inner shell and avoiding exacerbating the contraction force on the arc-shaped support portion. The arc-shaped support portion can utilize the full bonding force of the reinforcing base's plastic to resist the contraction force it bears. Furthermore, the inner support piece strengthens the arc-shaped support portion, increasing the bonding force between the arc-shaped support portion and the outer shell, and also supports both the arc-shaped support portion and the rounded corners, helping the rounded corners resist the contraction force of the sidewalls of the inner shell and reducing the possibility of cracking or separation from the outer shell.

[0029] The reinforcing ribs can support the arc support part and enhance the structural strength of the cap stud. Since the reinforcing ribs are not connected to the rounded corner part, they will not increase the shrinkage force borne by the rounded corner part.

[0030] The ejector section can increase the bonding force between the reinforcing plate and the bottom surface of the outer shell, and also facilitates the ejector pin to rest against. Compared with the ejector pin directly resting against the bottom surface of the outer shell, the load-bearing capacity is stronger after the ejector section is combined with the bottom surface of the outer shell, and the outer shell is less prone to deformation.

[0031] The waterproof reinforcement makes it easy to fit with the cover plate, improving the stability and sealing of the connection between the outer shell and the cover plate.

[0032] The injection-molded nut facilitates the fixation of the second embedded nut to the outer casing via injection molding. The hard contact between the second embedded nut and the inner bottom surface of the outer casing facilitates electrical conductivity between the outer casing and the second embedded nut. Since the second embedded nut is later used to install the circuit board, it further facilitates electrical conductivity between the outer casing and the circuit board. This allows the circuit board to be grounded through the metal outer casing, which can improve the electromagnetic compatibility of the internal electronic components.

[0033] The beneficial effects of this invention are:

[0034] 1. The outer shell is directly obtained through stamping, resulting in high production efficiency and high strength. Chemical treatment creates nanoscale pores on the inner surface of the outer shell, facilitating better bonding between the plastic and the shell during injection molding. After the inner shell is formed and cooled, it undergoes surface brushing and polishing, followed by ultrasonic cleaning in warm water. During surface brushing and polishing, localized instantaneous high temperatures on the outer surface of the outer shell are conducted to the nanoscale pores on the inner wall without affecting the plastic body of the inner shell. These localized instantaneous high temperatures help eliminate surface stress between the metal substrate and the plastic. After brushing and polishing, ultrasonic cleaning is performed in warm water. The ultrasonic vibrations during ultrasonic cleaning increase the crystallinity of the nanoscale crystalline plastic (PBT or PPS), improving its dimensional stability. The post-processing steps of surface polishing, brushing, and ultrasonic cleaning ensure the appearance of the outer shell and eliminate the need for prolonged high-temperature baking in traditional nano-injection molding processes, significantly improving production efficiency.

[0035] 2. The composite double-layer shell based on nano-injection molding has the advantages of high strength, light weight, good protection performance, good production consistency, excellent electromagnetic shielding performance and simple production process, making it very suitable for use in electronic equipment in coal mines.

[0036] 3. By utilizing a combination of in-mold preheating, cooling and uniform temperature shaping, wire drawing and polishing, and ultrasonic cleaning, the process of nano-injection molding is simplified while ensuring bonding strength. This includes processes such as preheating of external metal parts and high-temperature baking, which shortens the processing cycle and reduces processing difficulty. Attached Figure Description

[0037] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0038] Figure 1 This is a schematic diagram illustrating the overall structure of the composite deep frame shell in this invention.

[0039] Figure 2 This is an exploded structural diagram illustrating the perspective observation window in this invention.

[0040] Figure 3 This is a schematic diagram illustrating the structure of the hot-pressed cylinder after it has been hot-pressed in this invention.

[0041] Figure 4 This is a cross-sectional structural diagram illustrating the first wrapping layer in this invention.

[0042] Figure 5 This is a flowchart of the nano-injection molding manufacturing process for the composite deep frame shell in this invention.

[0043] Figure 6 This is a schematic diagram illustrating the structure of the ejector sleeve and ejector pin in this invention.

[0044] Figure 7This is a schematic diagram illustrating the structure of the limiting rod in this invention.

[0045] Figure 8 This is a schematic diagram illustrating the structure of the ejector rod in this invention.

[0046] Figure 9 This is a schematic diagram illustrating the structure of the first parting line in this invention.

[0047] Figure 10 This is a schematic diagram illustrating the structure of the sleeve in this invention.

[0048] Figure 11 This is a schematic diagram illustrating the structure of the uniform temperature cooling and shaping fixture in this invention.

[0049] In the diagram: 1. Outer shell; 11. Transparent window; 12. Hot-pressed hole; 13. Transparent observation window; 131. Sealing groove; 132. Observation window sealing ring; 133. Hot-pressed cylinder; 2. Inner shell; 31. Rounded corner; 311. Shrinkage groove; 32. Arc support; 33. Reinforcing base plate; 331. Ejector; 332. Injection nut; 333. Second inlaid nut; 34. Inner support plate; 341. Cover stud; 342. First inlaid nut; 343. Reinforcing rib; 35. First wrapping layer; 36. Waterproof rib; 37. Transparent window support plate; 38. Transparent window fitting ring; 4. Cover plate; 41. Side; 411. Screw hole; 42. Plastic 421. Skeleton; 422. Second Encasing Layer; 422. Screw Connection; 4221. Connecting Hole; 4222. Countersunk Hole; 423. Reinforcing Block; 424. Sealing Groove; 425. Sealing Ring; 4251. Clearance Hole; 5. Limiting Rod; 51. First Step; 52. Second Step; 53. Third Step; 6. Ejector Rod; 61. Fourth Step; 62. Fifth Step; 63. Sixth Step; 7. Ejector Pin; 71. Ejector Sleeve; 72. First Parting Line; 73. Irradiated Inner Core; 74. Irradiated Cover; 75. Second Parting Line; 761. Push Plate; 762. Ejector Block; 763. Ejector Pin; 771. First Ejector Rod; 772. Second Ejector Rod; 78. Gate. Detailed Implementation

[0050] The present invention will now be described in further detail with reference to the accompanying drawings. These drawings are simplified schematic diagrams, illustrating only the basic structure of the invention, and therefore only show the components relevant to the invention.

[0051] In a first aspect, the present invention discloses a composite deep frame shell.

[0052] Reference Figures 1 to 4A composite deep-frame shell includes an outer shell 1 and an inner shell 2. The inner shell 2 is injection-molded inside the outer shell 1. The inner shell 2 has rounded corner portions 31 and arc-shaped support portions 32. The arc-shaped support portions 32 are recessed and opposite to the rounded corner portions 31. There are four sets of rounded corner portions 31 and arc-shaped support portions 32. A reinforcing bottom plate 33 is integrally formed at the bottom of the arc-shaped support portion 32. The reinforcing bottom plate 33 is injection-molded to the inner bottom surface of the outer shell 1, but is not connected to the side wall of the inner shell 2. An inner support plate 34 is integrally formed between the arc-shaped support portion 32 and the inner shell 2. The inner support plate 34 is located at the bottom of the arc-shaped support portion 32 and is injection-molded to the inner bottom surface of the outer shell 1. The outer shell 1 can be made of 304 stainless steel with a wall thickness of 1-1.5 mm.

[0053] The arc-shaped support portion 32 supports the inner shell 2, helping the rounded corner portion 31 resist the contraction force transmitted from the side wall of the inner shell 2. The bonding force between the reinforcing base plate 33 and the bottom surface of the outer shell 1 works in conjunction with the arc-shaped support portion 32, distributing it along the height direction to the rounded corner portion 31, further resisting the contraction force transmitted from the side wall of the inner shell 2. Simultaneously, the reinforcing base plate 33 is not connected to the inner shell 2, preventing the transmission of its own contraction stress to the inner shell 2, thus avoiding exacerbating the contraction force on the arc-shaped support portion 32. The arc-shaped support portion 32 can utilize the entire bonding force between the reinforcing base plate 33 and the outer shell 1 to resist the contraction force it bears. Furthermore, the inner support plate 34 strengthens the arc-shaped support portion 32, increasing the bonding force between the arc-shaped support portion 32 and the outer shell 1, and also supports both the arc-shaped support portion 32 and the rounded corner portion 31, helping the rounded corner portion 31 resist the contraction force of the side wall of the inner shell 2, reducing the possibility of cracking or separation of the rounded corner portion 31 from the outer shell 1.

[0054] An integrally formed capping stud 341 is formed on the inner support plate 34. A first embedded nut 342 is provided inside the capping stud 341, which is adapted to connect with the cover plate. During injection molding, the positions of the outer shell 1 and the first embedded nut 342 are first determined by the mold, and then the capping stud 341 is formed by injection molding. At this time, the first embedded nut 342 is also covered and fixed by the capping stud 341. The capping stud 341 is connected to the arc-shaped support portion 32 by reinforcing ribs 343, and the reinforcing ribs 343 are arranged in pairs. The reinforcing ribs 343 can support the arc-shaped support portion 32 and enhance the structural strength of the capping stud 341. Since the reinforcing ribs 343 are not connected to the rounded corner portion 31, they do not increase the contraction force borne by the rounded corner portion 31. In this embodiment, there are four sets of capping studs 341 and first embedded nuts 342, located at the four corner points of the inner shell 2.

[0055] The inner shell 2 has an integrally formed first covering layer 35. The first covering layer 35 is injection molded to the end face of the outer shell 1. The first covering layer 35 increases the bonding area between the metal and the plastic, and provides tensile stress to the rounded corners 31 around the perimeter to resist shrinkage. In addition, the first covering layer 35 can serve as a mounting surface for connection with the cover plate. The flatness of the plastic-molded first covering layer 35 as a mounting surface is higher than that of the end face of the outer shell 1, which can reduce the requirements for the flatness of the end face of the outer shell 1 and reduce the processing difficulty of the outer shell 1.

[0056] A shrinkage groove 311 is provided on the inner side of the rounded corner portion 31, and the shrinkage groove 311 is provided along the height direction. The wall thickness of the rounded corner portion 31 is locally reduced by the shrinkage groove 311. Since the bonding force is only effective at the joint surface between the outer shell 1 and the inner shell 2, the local reduction of the wall thickness will not affect the bonding force at that point, but it can reduce the inherent shrinkage force generated by injection molding at this point.

[0057] An ejector portion 331 is integrally formed on the side of the reinforcing base plate 33, and the ejector portion 331 is connected to the bottom surface of the outer shell 1. The ejector portion 331 increases the bonding force between the reinforcing base plate 33 and the inner bottom surface of the outer shell 1, and facilitates the abutment of the ejector pins 7. Compared with the ejector pins 7 directly abutting against the inner bottom surface of the outer shell 1, the load-bearing capacity after the ejector portion 331 is combined with the inner bottom surface of the outer shell 1 is stronger, and the outer shell 1 is less prone to deformation. There are multiple ejector portions 331, so that multiple ejector pins 7 are ejected simultaneously, improving the stability of the movement when the outer shell 1 and the inner shell 2 are ejected.

[0058] A waterproof rib 36 is integrally formed on the end face of the inner shell 2. The waterproof rib 36 is arranged around the circumference of the inner shell 2 and is in a closed state. The waterproof rib 36 is suitable for cooperating with the cover plate, thereby improving the stability and sealing of the connection between the outer shell 1 and the cover plate.

[0059] The reinforcing base plate 33 has an integrally formed injection-molded nut portion 332, within which a second embedded nut 333 is provided. The second embedded nut 333 makes hard contact with the bottom surface of the outer casing 1. The injection-molded nut portion 332 facilitates the relative fixation of the second embedded nut 333 to the outer casing 1 through injection molding. The hard contact between the second embedded nut 333 and the inner bottom surface of the outer casing 1 facilitates electrical conductivity between the outer casing 1 and the second embedded nut 333. Since the second embedded nut 333 is later used to install a circuit board, it further facilitates electrical conductivity between the outer casing 1 and the circuit board, allowing the circuit board to be grounded through the metal outer casing 1, thereby improving the electromagnetic compatibility of internal electronic components. In this embodiment, there are four reinforcing base plates 33, four injection-molded nut portions 332, and four sets of second embedded nuts 333. Each reinforcing base plate 33 has one set of injection-molded nut portions 332 and one set of second embedded nuts 333.

[0060] Reference Figures 1 to 3The outer casing 1 has a viewing window 11, and a viewing window 13 is attached to the bottom surface of the outer casing 1, covering the viewing window 11. The viewing window 13 has a sealing groove 131, and a viewing window sealing ring 132 is installed in the sealing groove 131. A hot-pressed cylinder 133 is integrally formed on the viewing window 13, and several hot-pressed cylinders 133 are arranged in a circumferential array along the viewing window 11. Hot-pressed holes 12 are opened on the bottom surface of the outer casing 1 for the hot-pressed cylinders 133 to pass through. Several hot-pressed holes 12 are arranged in a circumferential array along the viewing window 11, and each corresponds to a hot-pressed cylinder 133. During installation, the viewing window 13 is attached to the bottom surface of the outer shell 1. At this time, the front end of the hot-pressed cylinder 133 passes through the hot-pressed hole 12. Then, the part of the hot-pressed cylinder 133 that passes through the hot-pressed hole 12 is deformed by hot pressing and anchored to the inner surface of the outer shell 1, thereby fixing the viewing window 13 to the outer shell 1.

[0061] In another embodiment, the first insert nut 342 can be welded to the inner bottom surface of the outer casing 1. Welding the first insert nut 342 to the inner surface of the outer casing 1 allows the first insert nut 342 to support the cap stud 341, thereby supporting the arc support portion 32 and the rounded corner portion 31, and assisting in bearing the contraction force on the rounded corner portion 31. The contraction force on the rounded corner portion 31 is not greater than the bonding force between the rounded corner portion 31 and the outer casing 1.

[0062] Secondly, this invention discloses a nano-injection molding manufacturing process for composite deep frame shells.

[0063] A nano-injection molding manufacturing process for composite deep frame shells, based on the aforementioned composite deep frame shells, with reference to... Figure 5 It includes the following steps:

[0064] S1. Stamping: Stamping the metal sheet to obtain the outer shell 1.

[0065] S2. Chemical treatment: The outer shell 1 is subjected to alkaline washing and acid washing, and then the inner surface of the outer shell 1 is treated with a treatment solution to form nanoscale pores. The treatment solution includes sodium acetate, sodium phosphate, disodium hydrogen phosphate, ethylenediaminetetraacetic acid (EDTA), and water. The content of sodium acetate is 20-40 g / L, the content of sodium phosphate is 5-30 g / L, the content of disodium hydrogen phosphate is 10-30 g / L, the content of EDTA is 1-20 g / L, and the remainder is water.

[0066] S3. Preheating: Place the outer shell 1 into the mold and preheat it through the mold.

[0067] Reference Figure 6The injection gates are located at the rounded corners 31. Since there are four rounded corners 31, there are also four injection gates. Positioning the injection gates near the rounded corners 31 enhances the bonding strength between the rounded corners 31 and the outer shell 1, helping to resist the shrinkage stress transmitted from the sidewalls of the inner shell 2. Nano-injection molding requires high plastic flowability to ensure that the injection-molded plastic quickly fills the nano-voids before cooling. Because the plastic at the injection gates has just entered the outer shell 1 and has not yet been cooled by the mold temperature, its flowability is stronger, resulting in better bonding strength at the gate. Simultaneously, the multiple injection gate design reduces filling and plastic cooling time, improving plastic flowability and bonding strength. After the inner shell 2 is injection molded, the gates 78 formed by the injection gates can be removed using CNC machining.

[0068] Specifically, refer to Figure 1 , Figures 6 to 8 The mold is equipped with a limiting rod 5, which is arranged circumferentially around the end face of the outer shell 1. The limiting rod 5 has a first step 51, a second step 52, and a third step 53. The first step 51 abuts against the end face of the outer shell 1, the second step 52 is adapted to be inserted into the inner shell 2, and the third step 53 is adapted to abut against the end face of the waterproof rib 36. After the inner shell 2 is formed, when the second step 52 is pulled out from the inner shell 2, an empty groove is formed on the inner shell 2. The mold is equipped with an ejector rod 6, which is arranged circumferentially around the end face of the outer shell 1. The ejector rod 6 has a fourth step 61, a fifth step 62, and a sixth step 63. The fourth step 61 abuts against the end face of the outer shell 1, the fifth step 62 is adapted to abut against the first wrapping layer 35, and the sixth step 63 is adapted to abut against the end face of the waterproof rib 36. During nano-injection molding, the outer shell 1 needs to be placed in the mold before injection molding. Positional deviation will cause injection separation problems. The limiting rod 5 is arranged circumferentially on the end face of the outer shell 1, which can ensure the positioning accuracy between the outer shell 1 and the inner shell 2 as much as possible. The ejector rod 6 can assist in supporting the outer shell 1, further improving the positioning accuracy between the outer shell 1 and the inner shell 2.

[0069] The mold is also equipped with ejector pins 7, which are adapted to abut against the ejector part 331, so that the outer shell 1 and the inner shell 2 can be ejected from the mold together when the mold is demolded.

[0070] Reference Figure 9 The first parting line 72 of the mold is set along the side wall, rounded corner 31 and arc support 32 of the inner shell 2, which can provide as much discharge area as possible for residual gas inside the cavity of the outer shell 1. The residual gas inside the cavity of the outer shell 1 can be discharged smoothly along the flow direction of plastic injection, avoiding the problem of trapped air, ensuring that the injection-molded colloid and nanopores are tightly bonded, and enhancing the bonding strength.

[0071] Reference Figure 6 and Figure 10The mold is equipped with a sleeve 71 that matches the second inlaid nut 333. When the mold is closed, the sleeve 71 presses against the second inlaid nut 333, so that the second inlaid nut 333 presses against the outer shell 1, thereby pressing the outer shell 1 against the mold core in the mold. This allows the mold core, which has a high heat capacity, to quickly heat the outer shell 1, thus achieving preheating of the outer shell 1 through the mold. This eliminates the need for separate preheating of metal parts outside the mold in traditional nano-injection molding processes, greatly improving production efficiency.

[0072] During injection molding, the mold positions and limits the outer shell 1 using the limiting rod 5 and the ejector rod 6. Then, the ejector sleeve 71 limits the first insert nut 342 and the second insert nut 333. Each first insert nut 342 and second insert nut 333 corresponds to one ejector sleeve 71, and the ejector sleeve 71 can be a stepped ejector sleeve 71. Then, the mold is closed. When the mold is closed, the ejector sleeve 71 presses against the second insert nut 333, so that the second insert nut 333 presses against the outer shell 1, thereby pressing the outer shell 1 against the mold core in the mold. This allows the mold core, which has a high heat capacity, to quickly heat the outer shell 1, thus achieving preheating of the outer shell 1 through the mold.

[0073] S4. Injection molding: After preheating, injection molding is performed through the sprue to fill the cavity between the outer shell 1 and the mold core. Then, injection molding is stopped, and the inner shell 2 is allowed to solidify.

[0074] The nano-injection molding material used in injection molding can be modified nano-sized PBT or PPS.

[0075] S5. Demolding: After the inner shell 2 solidifies, the mold separates, and the outer shell 1 is ejected from the mold core by the ejector pin 7. Then, the outer shell 1 and the inner shell 2, which are now integrated, are removed.

[0076] S6. Machining: Remove the gate left on the inner shell 2 due to the glue inlet by machining.

[0077] S7. Uniform temperature cooling and shaping: After the outer shell 1 is demolded, the uniform temperature cooling and shaping fixture is used to uniformly shape the outer shell 1.

[0078] Specifically, refer to Figure 11The homogenizing cooling and shaping fixture includes a homogenizing inner core 73 and a homogenizing cover 74. The homogenizing inner core 73 is inserted into the inner shell 2 and fits snugly against it. The homogenizing cover 74 makes hard contact with the bottom surface of the main shell and is connected to the homogenizing inner core 73 by bolts through the viewing window 11, thus reliably fitting the homogenizing inner core 73 to the inner shell 2. To ensure uniform cooling of all parts of the inner shell 2, the sidewalls of the homogenizing core are adapted to the inner shell 2, ensuring that the rounded corners 31 and injection-molded nut portions 332 on the inner shell 2 can fit snugly against the homogenizing core, ensuring uniform cooling and reducing stress generation. In addition, the homogenizing shaping fixture can also provide support to ensure the overall dimensional stability of the outer shell 1 and the inner shell 2.

[0079] S8. Polishing: Polish and brush the outer shell 1. During the surface brushing and polishing process, the localized instantaneous high temperature on the outer surface of the outer shell 1 can be conducted from the outside to the nanopores of the inner wall, but will not affect the plastic body of the inner shell 2. The localized instantaneous high temperature can help eliminate the surface stress between the metal substrate and the plastic.

[0080] S9. Cleaning: Ultrasonic cleaning is performed on the outer casing 1. After brushing and polishing, ultrasonic cleaning is carried out in warm water. The ultrasonic vibration during the ultrasonic cleaning process can increase the crystallinity of the nano-crystalline plastic (PBT or PPS) and improve its dimensional stability. By using the post-processing steps of surface polishing and brushing and ultrasonic cleaning, the appearance of the outer casing 1 can be guaranteed, and the long-term high-temperature baking process in the traditional nano-injection molding process can be eliminated, which greatly improves production efficiency.

[0081] S10, Perspective Observation Window 13 Hot Melt Assembly, Reference Figure 1 and Figure 2 Place the observation window sealing ring 132 into the sealing groove 131, pass the hot-pressed cylinder 133 through the pre-reserved hot-pressing hole 12 on the outer shell 1, and make the transparent observation window 13 fit with the outer shell 1. Then, press the part of the hot-pressed cylinder 133 that passes through the hot-pressing hole 12 by the hot-pressing plate, so that the diameter of the part of the hot-pressed cylinder 133 that passes through the hot-pressing hole 12 increases and makes hard contact with the inner bottom surface of the outer shell 1, so as to fix the transparent observation window 13 on the outer shell 1.

[0082] Based on the above-described preferred embodiments of the present invention, and through the foregoing description, those skilled in the art can make various changes and modifications without departing from the inventive concept. The technical scope of this invention is not limited to the contents of the specification, but must be determined according to the scope of the claims.

Claims

1. A nano-injection molding manufacturing process for composite deep-frame shells, characterized in that, The deep frame shell includes an outer shell and an inner shell injection-molded into the outer shell. The nano-injection molding manufacturing process of the composite deep frame shell includes the following steps: S1, Stamping, stamping the metal sheet to obtain the outer shell (1); S2, chemical treatment, by treating the inner surface of the outer shell (1) with a treatment solution to form nanoscale pores; S3. Preheating: Place the outer shell (1) into the mold and preheat it through the mold; S4. Injection molding: Injection molding is performed on the inner surface of the outer shell (1) to obtain the inner shell (2); S5. Demolding: Remove the outer shell (1) from the mold. S6. Temperature equalization cooling and shaping: After the outer shell (1) is demolded, the outer shell (1) and the inner shell (2) are uniformly shaped using a temperature equalization cooling and shaping fixture. The temperature equalization cooling and shaping fixture includes a temperature equalization inner core (73) and a temperature equalization cover (74). The temperature equalization inner core (73) is inserted into the inner shell (2) and fits snugly against the inner shell (2). The temperature equalization cover (74) is in hard contact with the bottom surface of the main shell and is connected to the temperature equalization inner core (73) by bolts. S7. Polishing: The surface of the outer shell (1) is brushed and polished so that the local instantaneous high temperature formed on the surface of the outer shell (1) helps to eliminate the surface stress between the outer shell (1) and the inner shell (2); S8. Cleaning: Ultrasonic cleaning is performed on the outer shell (1) so that the ultrasonic vibration during the cleaning process increases the crystallinity of the inner shell (2).

2. The composite deep frame shell nano-injection molding manufacturing process as described in claim 1, characterized in that, The inner shell (2) is provided with rounded corners (31). During injection molding, the injection port is located at the rounded corners (31). Each rounded corner (31) corresponds to one injection port. After the inner shell (2) is formed, the injection port is cut off by machining.

3. The composite deep frame shell nano-injection molding manufacturing process as described in claim 1, characterized in that, During injection molding, the mold is provided with a limiting rod (5), which is arranged along the circumference of the outer shell (1) on the end face of the outer shell (1). The limiting rod (5) is suitable for limiting the outer shell (1).

4. The composite deep frame shell nano-injection molding manufacturing process as described in claim 1, characterized in that, During injection molding, the mold is provided with an ejector rod (6), which is arranged along the circumference of the outer shell (1) on the end face of the outer shell (1). The ejector rod (6) is adapted to eject the outer shell (1) from the mold.

5. A composite deep-frame shell, characterized in that, The composite deep frame shell nano-injection molding manufacturing process as described in any one of claims 1-4 is applied.

6. The composite deep frame shell as described in claim 5, characterized in that, include Outer shell (1); Inner shell (2), which is injection molded inside outer shell (1), and the inner shell (2) is provided with rounded corners (31); The arc support part (32) is recessed and corresponds to the rounded corner part (31) of the inner shell (2); A reinforcing base plate (33) is connected to both the arc support portion (32) and the bottom surface of the outer shell (1); The inner support plate (34) is located between the arc support part (32) and the inner shell (2) and is located at the bottom of the arc support part (32). The inner support plate (34) is connected to the inner shell (2), the arc support part (32) and the outer shell (1). The inner support plate (34) is connected to a cover stud (341), and the cover stud (341) is provided with a first inlaid nut (342), which is suitable for connection with the cover plate; The cap stud (341) and the arc support part (32) are connected by a reinforcing rib (343); The reinforcing ribs (343) are arranged in pairs; The reinforcing base plate (33) has an ejector part (331) on its side, and the ejector part (331) is connected to the bottom surface of the outer shell (1); The inner shell (2) is provided with a waterproof rib (36) on its end face. The waterproof rib (36) is arranged around the circumference of the inner shell (2) and is in a closed state. The waterproof rib (36) is suitable for cooperating with the cover plate. The reinforcing base plate (33) is provided with an injection-molded nut part (332), and a second embedded nut (333) is provided inside the injection-molded nut part (332). The second embedded nut (333) is in hard contact with the bottom surface of the outer shell (1).

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