A double-shot overmolded product with an ultra-thick plastic cavity structure assembled in mold and its manufacturing process

Abstract

The application discloses a kind of double-shot encapsulation products of super-thick plastic part cavity structure in-mold assembly and production process thereof, by first barrel of double-shot injection molding machine, molten plastic material is injected into first injection mold cavity to form integrated first injection part and second injection part, then six-axis robot is controlled to drive pick-up installation tooling movement to grab insert and fix it on second injection part, at this time, second injection part and insert form an assembled part with closed cavity structure, finally, through second barrel of double-shot injection molding machine, molten plastic material is injected into the outer surface of second injection mold assembly to form third injection part;This technology can greatly reduce the overall weight of solid structure product, reduce material use, reduce material cost, and through the design of cavity structure, reduce product cooling time, improve production efficiency, completely eliminate surface shrinkage marks, internal irregular cavities and other product defects caused by excessive shrinkage of plastic material during cooling and solidification.

Description

Technical Field

[0001] This invention relates to the field of injection molding technology, and in particular to a double-injection overmolding product with an ultra-thick plastic part cavity structure assembled in the mold and its manufacturing process. Background Technology

[0002] Injection molding is a method of shaping industrial products. Products are usually made using rubber injection molding and plastic injection molding. Injection molding is the process of making various shapes of plastic products from thermoplastic or thermosetting materials using plastic molding dies. Injection molding is fast, efficient, and can be automated. It offers a wide variety of colors and shapes, from simple to complex, and sizes from large to small. Moreover, the product dimensions are precise, products are easy to update and replace, and it can produce complex-shaped parts. Injection molding is suitable for mass production and molding processing fields such as complex-shaped products.

[0003] In injection molding, such as Figure 5 The hook products shown are generally produced in three ways: direct overmolding, gas-assisted injection molding, and assembly of multiple components by injection molding. The thickness of the arc-shaped hook part is greater than 20mm, and injection molded products with a thickness exceeding 20mm are called ultra-thick-walled injection molded products.

[0004] When ultra-thick-walled injection molded products are directly overmolded, the following problems are likely to occur: (1) Shrinkage problem: After the overmolded injection material is overmolded, due to the long cooling time of the thick-walled part, the material will shrink excessively during the curing process, resulting in a smaller hook opening. In addition, the difference in shrinkage rate between the overmolded material and the injection material may also aggravate the shrinkage problem, causing the product to have defects such as deformation and cracking; (2) Efficiency problem: Ultra-thick-walled injection molded products are large in volume and heavy in weight, requiring a large injection pressure and injection volume during the injection process, which will increase the load on the injection molding machine and reduce the injection efficiency. In addition, due to the long cooling time of the thick-walled part, the molding cycle will also be extended accordingly, affecting production efficiency; (3) Appearance quality problem: During the overmolding process of ultra-thick-walled injection molded products, appearance quality problems such as surface bubbles, flow marks, missing glue, and flash may occur.

[0005] If gas-assisted injection molding is used, the following problems will occur: (1) Gas penetration: If gas penetrates the plastic melt during the injection process and reaches the product surface, gas penetration defects will be formed. This may cause bubbles, pores or gas marks on the product surface, affecting the appearance quality of the product; (2) Surface quality problems: In addition to surface problems caused by gas penetration and overflow, gas-assisted injection molding of ultra-thick wall injection molded products may also cause surface quality problems such as insufficient surface roughness, uneven gloss, and obvious weld lines. These problems may affect the appearance and market competitiveness of the product; (3) Instable weight: The weight of the product may fluctuate. This may be due to uneven flow of plastic melt, uneven gas distribution or unstable process parameters during the injection process.

[0006] If two hollow semi-circular hook parts are injection molded for assembly, the following problems will arise: (1) Appearance quality problem: Two hollow semi-circular hook parts need to be produced and then fused together by ultrasonic waves. However, when using ultrasonic fusion, there will be overflow of glue, which will affect the appearance of the product; (2) Performance problem: When two hollow semi-circular hook components are fixed by a snap-fit ​​structure, the overall strength is poor and the load-bearing capacity is insufficient. For some products with strength, sealing and other performance requirements, disassembling and reassembling may affect their performance; (3) Cost problem: Disassembling and injection molding increases the number of molds and assembly processes, which leads to increased costs. In addition, since quality control and inspection of two or more parts are required, the cost and workload of quality control will also increase; (4) Design limitations: Disassembling ultra-thick wall injection molded products into two or more injection molded parts for assembly may be subject to product design limitations. The structure of some products may not be suitable for disassembly, or disassembly may affect their function and performance. Summary of the Invention

[0007] To overcome the shortcomings of existing technologies, this invention provides a double-shot overmolded product with an in-mold assembly of an ultra-thick plastic part with a cavity structure and its manufacturing process, in order to solve the problems of product deformation, shrinkage, appearance quality, performance, production cost and production efficiency when directly overmolding, gas-assisted injection molding or assembling ultra-thick wall injection molded products.

[0008] To solve the above-mentioned technical problems, the present invention provides the following technical solution: a double-shot overmolding product with an ultra-thick plastic part cavity structure assembled in-mold, comprising:

[0009] First injection molded part;

[0010] At least one second injection molded part, wherein the second injection molded part is integrally injection molded with the first injection molded part;

[0011] An insert, wherein the insert is assembled and fixed in the mold of the second injection molded part to form an assembly with a closed cavity structure;

[0012] The third injection molded part is injection molded onto the outer surface of the assembly;

[0013] The second injection molded part has a slot and a first groove in sequence from the outside to the inside on the side facing the insert. A first rib is formed between the slot and the first groove. The insert has a second groove and a second rib adapted to the slot on the side facing the second injection molded part. A plurality of support ribs are provided at equal intervals in the second groove. There are side grooves on both sides of the support ribs and the second ribs that are adapted to the thickness of the first ribs. When the insert is fastened to the second injection molded part, the second rib is engaged in the slot, the support ribs are located in the first groove, and the first ribs are located in the second groove and the side grooves.

[0014] Preferably, the second injection molded part, the insert, and the third injection molded part are hook-shaped.

[0015] Preferably, the outer surface of the insert has a planar portion.

[0016] A manufacturing process for a double-shot overmolded product with an ultra-thick plastic part cavity structure assembled in-mold, used to produce the double-shot overmolded product with the ultra-thick plastic part cavity structure assembled in-mold, the manufacturing process includes the following steps:

[0017] Step 1: Insert fabrication:

[0018] The inserts required are injection molded using an injection molding machine;

[0019] Step Two: Machine-side Positioning

[0020] The insert is placed on the positioning fixture next to the twin-shot injection molding machine to facilitate accurate material handling of the insert in the future.

[0021] Step 3: Product molding in one shot:

[0022] Molten plastic material is injected into the first injection mold cavity through the first barrel of a double-shot injection molding machine to form a first injection molded part and a second injection molded part in one piece, thus forming a single-shot product. The double-shot injection molding machine includes a turntable, a first fixed mold, a second fixed mold, and a first moving mold and a second moving mold fixed on the turntable. The first moving mold and the second moving mold are exactly the same in shape and size.

[0023] Step 4: Rotate the turntable:

[0024] After the product is injection molded and cooled, the mold opening and turntable rotation of the double injection molding machine are controlled to exchange the positions of the first moving mold and the second moving mold.

[0025] Step 5: Remove and install the insert:

[0026] The six-axis robot is controlled to move the tooling to pick up the insert on the positioning fixture and fix it to the second injection molded part to form a semi-finished product. At this time, a closed assembly with a cavity structure is formed between the second injection molded part and the insert.

[0027] Step Six: Simultaneous Injection Molding (First and Second Injections):

[0028] When the double-shot injection molding machine closes the mold, the first barrel of the double-shot injection molding machine injects molten plastic material into the cavity of the first injection mold to form a first injection product. At the same time, the second barrel of the double-shot injection molding machine injects molten plastic material into the outer surface of the assembly of the second injection mold to form a third injection part, thus forming a double-shot overmolded product.

[0029] Step 7: Rotate the turntable:

[0030] After both the single-shot product and the double-shot overmolded product are injection molded, the double-shot injection molding machine opens the mold and rotates the turntable to exchange the positions of the first moving mold and the second moving mold.

[0031] Step 8: Take the double-shot coated product and install the insert:

[0032] The double-shot injection molding machine opens the mold. By controlling the five-axis robot installed on the double-shot injection molding machine to move to the first injection position, the double-shot overmolded product is taken out. At the same time, the six-axis robot is controlled to drive the part picking and installation tooling to grab the insert on the positioning fixture and fix it to the second injection part to form a semi-finished product.

[0033] Then repeat steps six, seven, and eight.

[0034] Preferably, the part removal and installation fixture includes a fixed plate, and a driving component, a support plate, and a part removal jig for adsorbing and fixing the insert are provided on one side of the fixed plate. The driving component is used to drive the part removal jig to move closer to or away from the support plate.

[0035] Preferably, in step six, the molding of the third injection molded part is performed in three stages: the first stage has an injection rate of 6 cm³ / s-7 cm³ / s and an injection pressure of 8 MPa; the second stage has an injection rate of 12 cm³ / s-13 cm³ / s and an injection pressure of 25 MPa; and the third stage has an injection rate of 8 cm³ / s-9 cm³ / s and an injection pressure of 10 MPa.

[0036] Compared with the prior art, the beneficial effects that this invention can achieve are:

[0037] This invention uses the first barrel of a dual-injection molding machine to inject molten plastic material into the cavity of a first injection mold to form a first and second injection molded part, which are integrally formed. Then, a six-axis robot is controlled to move a part-grabbing and installation fixture to grab an insert and fix it onto the second injection molded part. At this time, a closed assembly with a cavity structure is formed between the second injection molded part and the insert. Finally, the second barrel of the dual-injection molding machine injects molten plastic material into the outer surface of the assembly in the second injection mold to form a third injection molded part. This technology can greatly reduce the overall weight of solid structure products, reduce material usage, and lower material costs. Moreover, the cavity structure design reduces product cooling time, improves production efficiency, and completely eliminates product defects such as surface shrinkage marks and irregular internal voids caused by excessive shrinkage of plastic material during the cooling and solidification process. Attached Figure Description

[0038] Figure 1 This is a schematic diagram of the structure of a product according to the present invention;

[0039] Figure 2 This is a schematic diagram of the insert structure of the present invention;

[0040] Figure 3This is a schematic diagram of the first injection molded part, the second injection molded part, the insert, and the planar surface structure of the present invention;

[0041] Figure 4 This is a schematic diagram of the third injection molded part of the present invention;

[0042] Figure 5 This is a schematic diagram of the structure of the double-shot overmolded product of the present invention;

[0043] Figure 6 This is a schematic diagram of the CC cross-section (including cavity) structure of the double-shot overmolded product of the present invention;

[0044] Figure 7 This is a schematic diagram of the cross-sectional structure of the first rib, the support rib, and the second rib after the second injection molded part and the insert of the present invention are fixed.

[0045] Figure 8 This is a schematic diagram of the structure of the first barrel, the second barrel, the part-removing and installation fixture, the turntable, the six-axis robot, the five-axis manipulator and the positioning fixture of the present invention;

[0046] Figure 9 This is a schematic diagram of the structure of the first moving mold, the first fixed mold, the second moving mold, and the second fixed mold of the present invention;

[0047] Figure 10 This is a schematic diagram of the component removal and installation tooling structure of the present invention;

[0048] Figure 11 This is a schematic diagram of the structure of the first moving mold and the second moving mold after the single-shot product and the double-shot overmolded product are formed in step six of the present invention.

[0049] Figure 12 This is a schematic diagram of the structure of the first and second moving molds after the turntable rotates 180 degrees in step seven of the present invention, showing the single-shot product and the double-shot coated product on the first and second moving molds.

[0050] Figure 13 For the present invention Figure 12 A schematic diagram of the structure of a product shot at point A on the first moving mold;

[0051] Figure 14 This is a schematic diagram of the structure after the double-injection overmolded product is removed from the second moving mold and the insert is fixed on the second injection molded part on the first moving mold in step eight of the present invention.

[0052] Figure 15 For the present invention Figure 14 A schematic diagram of the semi-finished structure formed after the second injection molded part and the insert are fixed at point B;

[0053] The components are as follows: 1. First injection molded part; 2. Second injection molded part; 21. Slot; 22. First groove; 23. First rib; 3. Insert; 31. Support rib; 32. Second rib; 33. Second groove; 34. Side groove; 35. Flat part; 4. Third injection molded part; 51. First moving mold; 52. First fixed mold; 61. Second moving mold; 62. Second fixed mold; 7. Part removal and installation fixture; 71. Fixing plate; 72. Support plate; 73. Part removal jig; 74. Drive component; 8. Turntable; 91. First barrel; 92. Second barrel; 10. Six-axis robot; 11. Five-axis manipulator; 12. Positioning jig. Detailed Implementation

[0054] To make the technical means, creative features, objectives and effects of this invention easier to understand, the invention is further described below in conjunction with specific embodiments. However, the following embodiments are merely preferred embodiments of this invention and not all of them. Other embodiments obtained by those skilled in the art based on the embodiments in the implementation methods without creative effort are all within the protection scope of this invention.

[0055] like Figures 1-15 As shown, this invention provides a double-shot overmolded product with an ultra-thick plastic part cavity structure assembled in-mold and its manufacturing process, such as... Figures 1-7 As shown, the double-injection overmolded product includes a first injection molded part 1, at least one second injection molded part 2, an insert 3, and a third injection molded part 4;

[0056] The second injection molded part 2 is integrally injection molded with the first injection molded part 1;

[0057] Insert 3 and second injection molded part 2 are assembled and fixed in the mold to form a closed assembly with a cavity structure. The thickness of insert 3 after being fastened and fixed to second injection molded part 2 is 25mm. The outer contour size of insert 3 and second injection molded part 2 is the same.

[0058] The third injection molded part 4 is injection molded onto the outer surface of the assembly;

[0059] like Figures 8-15 As shown, a manufacturing process for a double-shot overmolded product with an ultra-thick plastic cavity structure assembled in-mold is described (the mold opening, mold closing, and rotation of the turntable 8 of the double-shot injection molding machine mentioned below are existing technologies, and their specific principles are not elaborated). This process is used to produce double-shot overmolded products with an ultra-thick plastic cavity structure assembled in-mold. The manufacturing process includes the following steps:

[0060] Step 1: Preparation of insert 3:

[0061] Insert 3 is required to be injection molded using an injection molding machine;

[0062] Step Two: Machine-side Positioning

[0063] like Figure 8 and Figure 10 As shown, the insert 3 is placed on the positioning fixture 12 next to the double injection molding machine, which facilitates the subsequent control of the six-axis robot 10 to drive the part picking and installation fixture 7 to accurately pick up the insert 3.

[0064] Step 3: Product molding in one shot:

[0065] like Figure 8 and Figure 9 As shown, molten plastic material (such as PP, ABS, and PC) is injected into the cavity of the first injection mold (which includes the first fixed mold 52 and its opposite first moving mold 51 or second moving mold 61) through the first barrel 91 of the dual-injection molding machine to form an integral first injection molded part 1 and second injection molded part 2, thus forming a single injection product. The dual-injection molding machine includes a turntable 8, a first fixed mold 52, a second fixed mold 62, and a first moving mold 51 and a second moving mold 61 that are exactly the same in shape and size and are fixed on the turntable 8.

[0066] Step 4: Rotate turntable 8:

[0067] After the product is injection molded, the double injection molding machine opens the mold and the turntable 8 rotates 180 degrees, so that the positions of the first moving mold 51 and the second moving mold 61 are interchanged.

[0068] Step 5: Install insert 3:

[0069] like Figure 8 and Figure 10 As shown, the six-axis robot 10 drives the part-grabbing and installation fixture 7 to grasp the insert 3 on the positioning jig 12 and fix it onto the second injection molded part 2, forming a semi-finished product (i.e., Figure 12 The first moving mold 51 on the first injection product state is converted to Figure 14 (In the semi-finished state on the first moving mold 51), at this time a closed assembly with a cavity structure is formed between the second injection molded part 2 and the insert 3;

[0070] Step Six: Simultaneous Injection Molding (First and Second Injections):

[0071] like Figure 8 As shown, after insert 3 is installed, the double-shot injection molding machine closes the mold. Simultaneously, the first barrel 91 of the double-shot injection molding machine injects molten plastic material into the cavity of the first injection mold to form a first-shot product. At the same time, the second barrel 92 of the double-shot injection molding machine injects molten plastic material into the outer surface of the assembly of the second injection mold (which includes the second fixed mold 62 and its opposite first moving mold 51 or second moving mold 61) to form the third injection molded part 4, thus forming a double-shot overmolded product (such as...). Figure 11 (as shown)

[0072] Step 7: Rotate turntable 8:

[0073] like Figure 11 and Figure 12 As shown, after both the single-shot product and the double-shot overmolded product are injection molded, the double-shot injection molding machine opens the mold and the turntable 8 rotates 180 degrees, so that the positions of the first moving mold 51 and the second moving mold 61 are interchanged.

[0074] Step 8: Take the double-shot coated product and install insert 3:

[0075] like Figure 8 As shown, the double-shot injection molding machine opens the mold. The five-axis robot 11, mounted on the machine, moves to the first injection position (at this time, the first fixed mold 52 is directly opposite the second moving mold 61), removing the double-shot overmolded product. Simultaneously, the six-axis robot 10 moves the part-grabbing and installation fixture 7 to grasp the insert 3 on the positioning jig 12 and fix it onto the second injection molded part 2, forming a semi-finished product. At this point, the product status on the first moving mold 51 and the second moving mold 61 changes from... Figure 12 Convert to Figure 14 As shown;

[0076] Then, repeat steps six, seven, and eight to complete the continuous processing and production of the double-shot coated product;

[0077] By setting the insert 3 and the second injection molded part 2 to form an assembly with a cavity, the overall weight of the double-shot overmolded product can be reduced, and the amount of injection molding material used can be reduced, thereby saving production costs. Moreover, the hollow design reduces the product's injection molding cooling time, improves production efficiency, and greatly reduces the excessive shrinkage of the material during the curing process, which can lead to product defects such as surface shrinkage marks and internal voids. It also reduces the injection pressure and injection volume, thereby reducing the load on the double-shot injection molding machine and improving injection efficiency. In addition, compared with the method of injection molding multiple components and then assembling them, it avoids the problems of the assembly process affecting the product's quality and performance, high production costs, and low production efficiency, thus improving the overall production quality and efficiency.

[0078] like Figure 1 , Figure 3 , Figure 5 and Figure 6 As shown, the first injection molded part 1 is in the shape of an animal head, making the double-shot overmolded product look like an art piece. The product shape is more novel and more appealing to people, especially children.

[0079] like Figures 1-5 As shown, the second injection molded part 2, the insert 3, and the third injection molded part 4 are hook-shaped;

[0080] Taking a double-shot coated product as an example of a hook with a hollow hook, an adhesive part needs to be installed on the first injection molded part 1 in the subsequent process. The double-shot coated product can be hung on the wall, so that items can be hung on the hook-shaped third injection molded part 4.

[0081] like Figure 1 and Figure 2 As shown, the second injection molded part 2 has a slot 21 and a first groove 22 in sequence from the outside to the inside on the side facing the insert 3. A first rib 23 is formed between the slot 21 and the first groove 22. The insert 3 has a second groove 33 and a second rib 32 that matches the slot 21 on the side facing the second injection molded part 2. Several support ribs 31 are provided at equal intervals in the second groove 33. There are side grooves 34 on both sides of the support ribs 31 and the second rib 32 that match the thickness of the first rib 23. When the insert 3 is fastened to the second injection molded part 2, the second rib 32 is engaged in the slot 21, the support ribs 31 are located in the first groove 22, and the first rib 23 is located in the second groove 33 and the side groove 34.

[0082] When the third injection part 4 is being injection molded, the pressure at the injection port is high and the pressure on the side away from the injection port is low. At this time, after the second fixed mold 62 and the first moving mold 51 are closed, the high temperature in the mold cavity will heat the insert 3 and the second injection part 2, making them soft, which will result in poor rigidity and affect the injection molding. However, by setting the support rib 31, it is not only convenient to fasten and fix the insert 3 and the second injection part 2, but the support rib 31 also abuts against the inner wall of the first groove 22 to form a rigid body, which enhances the rigidity of the semi-finished product.

[0083] In addition, the slot 21 cooperates with the second protruding rib 32 to achieve a good sealing and clamping effect, increasing the sealing of the insert 3 and the second injection molded part 2, and preventing the rubber material from seeping into the cavity structure during the injection of the third injection molded part 4.

[0084] like Figure 3 As shown, the outer surface of the insert 3 is provided with a flat portion 35. This arrangement facilitates the suction cup of the subsequent part removal fixture 73 to better adhere and fix the insert 3.

[0085] like Figure 8 and Figure 10 As shown, the part-removing installation fixture 7 includes a fixed plate 71. On one side of the fixed plate 71, there is a driving component 74 (the driving component 74 here can be a cylinder), a support plate 72, and a part-removing fixture 73 for adsorbing and fixing the insert 3 (a suction cup can be used, which is the prior art and will not be described in detail here). The driving component 74 is used to drive the part-removing fixture 73 to move closer to or away from the support plate 72.

[0086] By setting up a support plate 72, a drive component 74, and a part removal fixture 73, when it is necessary to fasten the insert 3 onto the second injection molded part 2, in order to ensure that the first injection molded part 1 and the second injection molded part 2 do not move on the first moving mold 51 or the second moving mold 61 during the assembly of the insert 3, the subsequent injection molding of the third injection molded part 4 can proceed smoothly.

[0087] Specifically, when the insert 3 needs to be installed (specifically, the insert 3 is removed from the positioning fixture 12 by being attracted and fixed by the part-removing fixture 73 through the flat part 35 on the outer surface of the insert 3), the six-axis robot 10 moves the fixing plate 71 so that the side of the support plate 72 facing the part-removing fixture 73 is in contact with the second injection molded part 2. Then, the drive component 74 is adjusted to move the part-removing fixture 73 closer to the second injection molded part 2 until the insert 3 is fastened and fixed to the second injection molded part 2. This ensures that when the insert 3 is assembled in the mold, the first injection molded part 1 and the second injection molded part 2 will not move on the first moving mold 51 or the second moving mold 61, and at the same time, it ensures that there is no gap after the insert 3 and the second injection molded part 2 are fastened.

[0088] In step six, the molding of the third injection part 4 is carried out in three stages: the injection rate of the first stage is 6cm³ / s-7cm³ / s and the injection pressure is 8MPa; the injection rate of the second stage is 12cm³ / s-13cm³ / s and the injection pressure is 25MPa; and the injection rate of the third stage is 8cm³ / s-9cm³ / s and the injection pressure is 10MPa.

[0089] Before the third injection part 4 is injected into the mold of the double-shot injection molding machine, there is a gap between the assembled part after the insert 3 and the second injection part 2 are engaged and the inner wall of the mold cavity of the second fixed mold 62 that is adapted to the size of the third injection part 4. The product gate is filled in a ring by low-speed and low-pressure injection through a single-side gate. This prevents the assembly from bending and contacting the mold cavity due to excessive injection rate and injection pressure, which would cause incomplete molding. Low speed and low pressure can prevent flow marks or air marks caused by melt spraying and ensure that the melt contacts the mold wall smoothly to form a smooth surface. The injection rate and injection pressure are increased in the middle to quickly fill the gap. Finally, low speed and low pressure injection is used to facilitate timely venting.

[0090] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A two-shot overmolding product for in-mold assembly of a super-thick plastic part cavity structure, characterized in that, Comprise: First injection molding part (1); At least one second injection molding part (2), the second injection molding part (2) is integrally injection molded with the first injection molding part (1); Insert (3), the insert (3) is fixedly combined with the second injection molding part (2) in the mold and forms an assembled part with a closed cavity structure; The third injection molding part (4) is injection molded on the outer surface of the assembled part; The second injection molding part (2) has a clamping groove (21) and a first groove (22) from outside to inside on the side facing the insert (3), a first convex rib (23) is formed between the clamping groove (21) and the first groove (22), the insert (3) has a second groove (33) and a second convex rib (32) matched with the clamping groove (21) on the side facing the second injection molding part (2), a plurality of support ribs (31) are equidistantly arranged in the second groove (33), the support ribs (31) have a side groove (34) with a thickness matched with the first convex rib (23) between the two sides and the second convex rib (32), when the insert (3) is combined with the second injection molding part (2), the second convex rib (32) is clamped in the clamping groove (21), the support rib (31) is located in the first groove (22), and the first convex rib (23) is located in the second groove (33) and the side groove (34).

2. The over-thickness plastic part cavity structure in-mold assembled two-shot encapsulated product of claim 1, wherein: The second injection molding part (2), the insert (3) and the third injection molding part (4) are hook-shaped.

3. The over-thickness plastic part cavity structure in-mold assembled two-shot encapsulated product of claim 2, wherein: The outer surface of the insert (3) is provided with a flat part (35).

4. A process for the production of a two-shot encapsulated product for in-mould assembly of a super-thick plastic part cavity structure, characterised in that, The production process of the double-shot encapsulated product for producing the in-mold assembly of the super-thick plastic part cavity structure of any one of claims 1-3 comprises the following steps: Step one: preparation of the insert (3): Injection molding of the required insert (3) by using an injection molding machine; Step two: machine edge positioning: Place the insert (3) on the positioning jig (12) beside the double-shot injection molding machine to facilitate subsequent accurate taking of the insert (3); Step three: one-shot product forming: Melted plastic material is injected into the first injection mold cavity by the first barrel (91) of the double-shot injection molding machine to form an integrated first injection molding part (1) and a second injection molding part (2), forming a one-shot product, wherein the double-shot injection molding machine comprises a turntable (8), a first fixed mold (52), a second fixed mold (62), and a first movable mold (51) and a second movable mold (61) fixed on the turntable (8), wherein the first movable mold (51) and the second movable mold (61) are completely the same in shape and size; Step four: rotating the turntable (8): After one-shot product injection molding and cooling, control the double-shot injection molding machine to open the mold, rotate the turntable (8) by 180 degrees, and exchange the positions of the first movable mold (51) and the second movable mold (61); Step five: taking the insert (3) and installing: Control the six-axis robot (10) to drive the taking and installing tooling (7) to move to grab the insert (3) on the positioning jig (12) and fix it on the second injection molding part (2) to form a semi-finished product, at this time, the second injection molding part (2) and the insert (3) form an assembled part with a closed cavity structure; Step six: one-shot and two-shot injection molding simultaneously: The mold of the double-shot injection molding machine is closed, and the first barrel (91) of the double-shot injection molding machine injects molten plastic material into the first injection mold cavity to form a first injection product, while the second barrel (92) of the double-shot injection molding machine injects molten plastic material into the outer surface of the assembly of the second injection mold to form a third injection part (4), thereby forming a double-shot encapsulated product. Step seven: rotate the turntable (8): After the first injection product and the double-shot encapsulated product are injection molded, the double-shot injection molding machine is opened, and the turntable (8) is rotated by 180 degrees to exchange the positions of the first movable mold (51) and the second movable mold (61); Step eight: take the double-shot encapsulated product and install the insert (3): The double-shot injection molding machine is opened, and the five-axis robot (11) installed on the double-shot injection molding machine is controlled to move to the first injection position to take out the double-shot encapsulated product. At the same time, the six-axis robot (10) is controlled to drive the taking and installing tooling (7) to move to grab the insert (3) on the positioning jig (12) and fix it on the second injection part (2), thereby forming a semi-finished product. Then repeat steps six, seven, and eight.

5. The process for producing a dual shot overmolded product of an ultra thick plastic part cavity structure mold-in place assembly of claim 4, wherein: The taking and installing tooling (7) includes a fixed plate (71), one side of the fixed plate (71) is provided with a driving member (74), a support plate (72), and a taking jig (73) for adsorbing and fixing the insert (3), and the driving member (74) is used to drive the taking jig (73) to move close to or away from the support plate (72).

6. A process for the production of a dual shot overmolded product of an ultra thick plastic part cavity structure mold-in place assembly as claimed in claim 4, wherein: In step six, the molding of the third injection part (4) is divided into three stages, the first stage injection rate is 6cm³ / s-7cm³ / s, the injection pressure is 8Mpa, the second stage injection rate is 12cm³ / s-13cm³ / s, the injection pressure is 25Mpa, and the third stage injection rate is 8cm³ / s-9cm³ / s, the injection pressure is 10Mpa.

Images