Nested partitioned vacuum insert for film-coated injection molds

Abstract

This invention provides a nested, zoned, controlled vacuum insert for film-coated injection molds. A first cavity is provided on the core-side main insert, and an external vacuum insert is disposed within the first cavity. A first vacuum gap, communicating with the cavity, is formed between the outer wall of the external vacuum insert and the inner wall of the first cavity. A first air passage is provided on the external vacuum insert, communicating with the first vacuum gap to form an outer air passage. A second cavity is provided on the external vacuum insert, and an internal vacuum insert is disposed within the second cavity. A second vacuum gap, communicating with the cavity, is formed between the outer wall of the internal vacuum insert and the inner wall of the second cavity. A second air passage is provided on the internal vacuum insert, communicating with the second vacuum gap to form an inner air passage. A main air passage, communicating with an external vacuum device, is provided on the insert body. The first and second air passages are connected to the main air passage. The overall design of this invention is simple, with a reasonable distribution of adsorption force, and also incorporates the characteristics of flexible production.

Description

Technical Field

[0001] This invention relates to the field of injection mold technology, and more specifically, to a nested partitioned vacuum control insert for film-coated injection molds. Background Technology

[0002] In in-mold decoration injection molding, a film needs to be adhered to a designated area within the mold cavity in a specific way. For relatively large films, vacuum suction is a good option. However, ensuring the film adheres smoothly and evenly to the cavity presents a significant challenge. Stronger vacuum suction force is not necessarily better; proper distribution of suction force is key. Existing molds of this type often fail to achieve a smooth and even adhesion of the film to the cavity wall, resulting in localized gaps between the film and the cavity. These gaps lead to defects such as film displacement and localized wrinkles in the final injection molded product, failing to meet the production requirements of high-quality film-coated injection molded products. Summary of the Invention

[0003] To address the shortcomings of existing technologies, the purpose of this invention is to provide a nested, zoned, vacuum-controlled insert for film-coated injection molds.

[0004] According to the present invention, a nested partitioned vacuum control insert for a film-coated injection mold includes: an insert body; a cavity is formed between the mold core side mold and the mold cavity side mold; the insert body is disposed on the mold core side mold and corresponding to the cavity; the insert body includes: a core side main insert, an outer vacuum insert, and an inner vacuum insert;

[0005] The core-side main insert is provided with a first cavity, and the external air extraction insert is disposed in the first cavity. A first air extraction gap communicating with the cavity is formed between the outer side wall of the external air extraction insert and the inner side wall of the first cavity. The external air extraction insert is provided with a first air passage, and the first air passage communicates with the first air extraction gap to form an outer air passage.

[0006] The outer air extraction insert is provided with a second cavity, and the inner air extraction insert is disposed in the second cavity. A second air extraction gap communicating with the cavity is formed between the outer side wall of the inner air extraction insert and the inner side wall of the second cavity. The inner air extraction insert is provided with a second air passage, and the second air passage communicates with the second air extraction gap to form an inner air passage.

[0007] The first and second air extraction gaps can fix the product film portion located in the cavity by air extraction; the insert body is provided with a main air channel that communicates with an external air extraction device, and the first and second air channels are connected to the main air channel.

[0008] Preferably, the first airway is connected to the main airway via the second airway.

[0009] Preferably, a first sealing port is provided on the first airway;

[0010] The first sealing port can be sealed by the first sealing element, so that the first air extraction gap is not connected to the main air passage.

[0011] Preferably, a second sealing port is provided on the second airway;

[0012] The second sealing port can be sealed by the second sealing element, so that the first air extraction gap and / or the second air extraction gap are not connected to the main air passage.

[0013] Preferably, the positions of the air inlets of the first and second air extraction gaps correspond to different positions within the cavity.

[0014] Preferably, the first air extraction gap and the second air extraction gap are distributed from the outside to the inside on the insert body.

[0015] Preferably, a plurality of first air extraction gaps are formed between the outer sidewall of the external air extraction insert and the inner sidewall of the first cavity.

[0016] Multiple first air extraction gaps are distributed at intervals along the circumference of the external air extraction insert;

[0017] The external air extraction insert is provided with a plurality of first air channels, and the first air channels are connected to the first air extraction gap one by one to form a plurality of external air channels.

[0018] The first sealing ports on the multiple first air passages can be sealed or opened independently.

[0019] Preferably, a plurality of second air extraction gaps are formed between the outer side wall of the inner air extraction insert and the inner side wall of the second cavity;

[0020] Multiple second air extraction gaps are distributed at intervals along the circumference of the inner air extraction insert;

[0021] The inner air extraction insert is provided with a plurality of second air passages, and the second air passages are connected to the second air extraction gaps one by one to form a plurality of inner air passages.

[0022] The second sealing ports on the multiple second air passages can be sealed or opened independently.

[0023] Preferably, the insert body is provided in multiple forms;

[0024] The first and second air extraction gaps on the multiple insert bodies correspond to different positions within the cavity.

[0025] Preferably, the plurality of insert bodies are arranged in a distributed manner along the length or width direction of the mold core side mold.

[0026] Compared with the prior art, the present invention has the following beneficial effects:

[0027] 1. This invention provides an air intake insert and air passage design that can generate effective adsorption force. Through a simple and ingenious structural design, a relatively stronger negative pressure is generated near the center of the diaphragm than at the periphery, so that the diaphragm fits fully with the cavity from the inside out, effectively preventing the generation of local gaps between the diaphragm and the cavity.

[0028] 2. The vacuum gas path of the present invention has considerable flexibility, allowing the inserts to be redesigned when the size and dimensions of the diaphragm change. Simply closing the gas path outside the coverage area of ​​the diaphragm ensures that sufficient adsorption force can be generated even when facing irregularly shaped diaphragms. The entire design structure is simple, the adsorption force is reasonably distributed, and it also has the characteristics of flexible production.

[0029] 3. This invention uses a nested insert design, with an inner air extraction insert nested within an outer air extraction insert. The main air channel is positioned at the center of the air extraction insert, and the air channels are arranged in a way that diffuses outwards. This design naturally balances the air channels, ensuring uniform suction distribution while maintaining a slightly stronger suction force on the inner air channels than on the outer air channels. This is because the inner air channels are closer to the main air channel and have lower flow resistance. This suction distribution effectively prevents the diaphragm from arching or wrinkling in the cavity, ensuring that the diaphragm fits the cavity perfectly. Attached Figure Description

[0030] Other features, objects, and advantages of the present invention will become more apparent from the following detailed description of non-limiting embodiments with reference to the accompanying drawings:

[0031] Figure 1 An exploded view of the product composition;

[0032] Figure 2 A schematic diagram of the structure for placing the diaphragm into the mold;

[0033] Figure 3 This is the normal view of the mold parting surface;

[0034] Figure 4 for Figure 3 A cross-sectional view along line AA;

[0035] Figure 5 for Figure 4 A magnified view of a portion of the central X-section;

[0036] Figure 6 for Figure 3A cross-sectional view along line BB;

[0037] Figure 7 To highlight the structural diagrams of the main airway, medial airway, and lateral airway;

[0038] Figure 8 This is a schematic diagram of the airflow distribution and direction of a single set of suction inserts when the air passage is fully open;

[0039] Figure 9 Detailed drawings of the model parting surface top view and the corner seal design of the insert;

[0040] Figure 10 The top view of the model parting surface is used to highlight the air extraction gap;

[0041] Figure 11 A schematic diagram of the cross-section of a single suction insert when the outer airway on one side is closed;

[0042] Figure 12 A schematic diagram of the cross-section of a single set of suction inserts when the outer airways on both sides are closed;

[0043] Figure 13 A schematic diagram of the cross-section of a single set of air extraction inserts when the inner and outer air passages on one side are closed;

[0044] Figure 14 This is a top view of the mold parting surface when it is not coated.

[0045] Figure 15 A top view of the mold parting surface when the entire covering membrane is adsorbed;

[0046] Figure 16 Top view of the mold parting surface when the first partial covering film is adsorbed;

[0047] Figure 17 A top view of the mold parting surface when the second partial covering film is adsorbed;

[0048] Figure 18 A top view of the mold parting surface when the third local covering film is adsorbed;

[0049] Figure 19 This is a top view of the mold parting surface when the fourth local covering film is adsorbed.

[0050] The diagram shows:

[0051] Product diaphragm section 1; Product injection molding section 2; Mold cavity side mold 3; Mold core side mold 4; Core side main insert 5; Cavity 6; External air extraction insert 7; Internal air extraction insert 8; Sealing gasket 9; First seal 11; Second seal 12; Inner insert locking screw hole 13; Outer insert locking screw hole 14; Main air passage 15; Inner air passage 16; Second air extraction gap 161; Second air passage 162; Second sealing port 163; Outer air passage 17; First air extraction gap 171; First air passage 172; First sealing port 173; Overall covering diaphragm 18; First partial covering diaphragm 19; Second partial covering diaphragm 20; Third partial covering diaphragm 21; Fourth partial covering diaphragm 22. Detailed Implementation

[0052] The present invention will now be described in detail with reference to specific embodiments. These embodiments will help those skilled in the art to further understand the present invention, but do not limit the invention in any way. It should be noted that those skilled in the art can make several changes and improvements without departing from the concept of the present invention. These all fall within the protection scope of the present invention.

[0053] Example 1

[0054] like Figures 1 to 19 As shown, this embodiment provides a nested partitioned vacuum control insert for a film-coated injection mold, comprising: an insert body; a cavity 6 formed between the mold core-side mold 4 and the mold cavity-side mold 3; the insert body is disposed on the mold core-side mold 4 and corresponding to the cavity 6; the insert body includes: a core-side main insert 5, an external vacuum insert 7, and an internal vacuum insert 8; a first cavity is provided on the core-side main insert 5, the external vacuum insert 7 is disposed in the first cavity, and a first vacuum gap 171 communicating with the cavity 6 is formed between the outer side wall of the external vacuum insert 7 and the inner side wall of the first cavity; a first air passage 172 is provided on the external vacuum insert 7, and the first air passage 172 communicates with the first vacuum gap 6. The gap 171 connects to form an outer air passage 17; the outer air extraction insert 7 is provided with a second cavity, the inner air extraction insert 8 is provided in the second cavity, and a second air extraction gap 161 communicating with the cavity 6 is formed between the outer side wall of the inner air extraction insert 8 and the inner side wall of the second cavity; the inner air extraction insert 8 is provided with a second air passage 162, and the second air passage 162 communicates with the second air extraction gap 161 to form an inner air passage 16; the first air extraction gap 171 and the second air extraction gap 161 can fix the product film portion 1 located in the cavity 6 by air extraction; the insert body is provided with a main air passage 15 communicating with the external air extraction device, and the first air passage 172 and the second air passage 162 communicate with the main air passage 15.

[0055] The positions of the air extraction ports of the first air extraction gap 171 and the second air extraction gap 161 correspond to different positions within the cavity 6. The first air extraction gap 171 and the second air extraction gap 161 are distributed from the outside to the inside on the insert body. Multiple first air extraction gaps 171 are formed between the outer sidewall of the outer air extraction insert 7 and the inner sidewall of the first cavity; the multiple first air extraction gaps 171 are distributed at intervals along the circumference of the outer air extraction insert 7; multiple first air passages 172 are provided on the outer air extraction insert 7, and the first air passages 172 are connected to the first air extraction gaps 171 one by one to form multiple outer air passages 17; the first sealing ports 173 on the multiple first air passages 172 can be sealed or opened independently. Multiple second suction gaps 161 are formed between the outer side wall of the inner suction insert 8 and the inner side wall of the second cavity; the multiple second suction gaps 161 are distributed at intervals along the circumference of the inner suction insert 8; multiple second air passages 162 are provided on the inner suction insert 8, and the second air passages 162 are connected to the second suction gaps 161 in a one-to-one correspondence to form multiple inner air passages 16; the second sealing ports 163 on the multiple second air passages 162 can be sealed or opened independently.

[0056] The first air passage 172 is connected to the main air passage 15 via the second air passage 162. The first air passage 172 is provided with a first sealing port 173; the first sealing port 173 can be sealed by a first sealing element 11, preventing the first suction gap 171 from communicating with the main air passage 15. The second air passage 162 is provided with a second sealing port 163; the second sealing port 163 can be sealed by a second sealing element 12, preventing the first suction gap 171 and / or the second suction gap 161 from communicating with the main air passage 15.

[0057] Multiple insert bodies are provided; the first evacuation gap 171 and the second evacuation gap 161 on the multiple insert bodies correspond to different positions within the cavity 6. The multiple insert bodies are distributed and arranged along the length or width direction of the mold core side mold 4.

[0058] The mold is divided into a cavity-side mold 3 and a core-side mold 4. The diaphragm is adsorbed onto the core-side mold 4. The suction insert is set within the enclosure of the core-side main insert 5, and the resin is injected into the cavity 6 during injection molding.

[0059] Unlike designs that directly open holes in the mold cavity, the evacuation system in this embodiment has an evacuation gap of only h = 0.02mm to 0.2mm. During injection molding of part 2 of the product, the high-temperature and high-pressure molten resin will squeeze the diaphragm, creating a clamping line on one side of the diaphragm part 1, but this does not affect the integrity and shape accuracy of the diaphragm part 1. In areas not covered by the diaphragm, this width of gap can effectively prevent resin from flowing into the air passage, making the evacuation system easy to maintain.

[0060] like Figure 9As shown, by introducing two sections of length a and b without any suction gaps at the four corners of the suction insert, four independent suction gaps are created around the insert. Typical widths are a = 5mm–10mm and b = 5mm–10mm. Combined with the ingenious internal design of the insert, simply screwing in the first seal 11 and / or the second seal 12 at the corresponding airway positions—the first seal 11 being an outer sealing screw and the second seal 12 an inner sealing screw—can close the external airway on a specific side or simultaneously close both the internal and external airways on one side. By closing the airways in the uncoated areas, various irregularly shaped diaphragms can be easily accommodated without redesigning the suction system. This makes the entire suction system flexible without sacrificing suction efficiency. In situations where independent zone control is not required, a = 0 and b = 0.

[0061] Because vacuum systems require extremely high airtightness, even a single leak can affect the overall vacuum efficiency. Unlike designs that extend the main air duct to the bottom of the insert and then machine air ducts into the bottom and sides of the insert, this design cleverly uses perforations to introduce the main air duct into the side of the insert closest to the cavity. Then, horizontal perforations diffuse the air duct outwards to every side of the insert. Sealing gaskets 9 are placed around the air duct at the bottom of each insert layer to minimize the possibility of gas entering the vacuum duct through the gaps in the locking screw holes 13 of the inner insert and / or 14 of the outer insert. This ensures that gas can only enter the air duct from the cavity surface. This guarantees both suction force and the efficiency of the vacuum system.

[0062] Unlike methods that only utilize the outer side of the suction insert to create an air passage, this embodiment uses nested inserts. The outer suction insert 7 contains the inner suction insert 8, with the main air passage 15 positioned at the center of the suction insert, and the air passages arranged in a diffusing manner. This air passage design naturally balances the flow, ensuring uniform suction distribution while maintaining a slightly stronger suction in the inner air passage 16 compared to the outer air passage 17. This is because the inner air passage is closer to the main air passage, resulting in lower flow resistance. This suction distribution effectively prevents the diaphragm from arching or wrinkling in the cavity, ensuring a perfect fit between the diaphragm and the cavity.

[0063] Because of its modular air extraction unit design, it can be easily matrixed and replicated in various corners of the cavity. It is suitable for cavity designs of different shapes.

[0064] Before molding begins, the mold is opened, and the product film portion 1 is placed into one side of the mold mechanically or manually. In this embodiment, the product film portion 1 is placed into the core-side mold 4. Due to the presence of the vacuum system, the product film portion 1 can be firmly adhered to the core-side mold 4. Next is mold closing. Driven by the mold closing action of the molding machine, the cavity-side mold 3 and the core-side mold 4 will fit tightly together. The cross-section after fitting is as follows. Figure 4 and Figure 6 As shown. Next comes injection molding, where molten plastic is poured into cavity 6 through the gate. After cooling, the mold opens, and the product is ejected, resulting in a product where the film and the plastic product are fused together. In this embodiment, the location of the gate is not specifically indicated because it could be a side gate or a direct gate; there are many possibilities.

[0065] In this embodiment, to design the main air channel as short and direct as possible, the air channel is vertically perforated at the center of the insert, and then connected to the side of the insert through lateral perforation. A nested design is also used to form two suction gaps, an inner ring and an outer ring. By cleverly utilizing the difference in distance between the inner ring suction gap and the main air channel compared to the outer ring, a suction layout with stronger inner ring suction than outer ring suction is created, effectively preventing the diaphragm from arching in the middle. This improves the fit between the diaphragm and the cavity and prevents defects such as diaphragm deformation during injection molding.

[0066] This embodiment uses fewer inserts, making its design and installation relatively simple. It also incorporates appropriate design considerations for the rationality and controllability of suction distribution. In scenarios involving adsorption and membrane fixation, it not only effectively expels gas but also achieves a reasonable distribution of suction strength. In membrane adsorption scenarios, it's impractical to arrange the suction gaps densely, as this would lead to poor heat dissipation, creating localized hotspots and affecting the forming cycle. The suction insert design used in this embodiment features a simple airflow channel with the main airflow channel concentrated inside the insert. There are fewer gaps between inserts, and the contact area between inner and outer inserts is large. This facilitates efficient heat dissipation and avoids the formation of localized hotspots.

[0067] The overall design of this invention is simple, with a reasonable distribution of adsorption force and the characteristics of flexible production.

[0068] In the description of this application, it should be understood that the terms "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application.

[0069] Specific embodiments of the present invention have been described above. It should be understood that the present invention is not limited to the specific embodiments described above, and those skilled in the art can make various changes or modifications within the scope of the claims, which do not affect the essence of the present invention. Unless otherwise specified, the embodiments and features described in this application can be arbitrarily combined with each other.

Claims

1. A nested, zoned, controlled vacuum insert for film-coated injection molds, characterized in that, include: The insert body; a cavity (6) is formed between the mold core side mold (4) and the mold cavity side mold (3); the insert body is disposed on the mold core side mold (4) and is disposed corresponding to the cavity (6); the insert body includes: core side main insert (5), external air extraction insert (7) and internal air extraction insert (8). The core-side main insert (5) is provided with a first cavity, and the external air extraction insert (7) is provided in the first cavity. A first air extraction gap (171) communicating with the cavity (6) is formed between the outer side wall of the external air extraction insert (7) and the inner side wall of the first cavity. The external air extraction insert (7) is provided with a first air passage (172), and the first air passage (172) communicates with the first air extraction gap (171) to form an outer air passage (17). The outer suction insert (7) is provided with a second cavity, and the inner suction insert (8) is provided in the second cavity. A second suction gap (161) communicating with the cavity (6) is formed between the outer side wall of the inner suction insert (8) and the inner side wall of the second cavity. The inner suction insert (8) is provided with a second air passage (162), and the second air passage (162) communicates with the second suction gap (161) to form an inner air passage (16). The first air extraction gap (171) and the second air extraction gap (161) can fix the product film portion (1) located in the cavity (6) by air extraction; the insert body is provided with a main air channel (15) that communicates with the external air extraction device, and the first air channel (172) and the second air channel (162) are connected to the main air channel (15); The first airway (172) is provided with a first sealing port (173); The first sealing port (173) can be sealed by the first sealing element (11) so that the first air extraction gap (171) is not connected to the main air passage (15); The second air passage (162) is provided with a second sealing port (163); The second sealing port (163) can be sealed by the second sealing element (12) so that the first air extraction gap (171) and / or the second air extraction gap (161) are not connected to the main air passage (15); Multiple first air extraction gaps (171) are formed between the outer sidewall of the external air extraction insert (7) and the inner sidewall of the first cavity. Multiple first air extraction gaps (171) are distributed at intervals along the circumference of the external air extraction insert (7); The external air extraction insert (7) is provided with a plurality of first air passages (172), and the first air passages (172) are connected to the first air extraction gap (171) in a one-to-one correspondence to form a plurality of external air passages (17). The first sealing ports (173) on the multiple first air passages (172) can be sealed or opened independently; A plurality of second air extraction gaps (161) are formed between the outer side wall of the inner air extraction insert (8) and the inner side wall of the second cavity. Multiple second air extraction gaps (161) are arranged at circumferential intervals along the inner air extraction insert (8); The inner air extraction insert (8) is provided with a plurality of second air passages (162), and the second air passages (162) are connected to the second air extraction gap (161) in a one-to-one correspondence to form a plurality of inner air passages (16). The second sealing ports (163) on the multiple second air passages (162) can be sealed or opened independently.

2. The nested partitioned vacuum insert for film-coated injection molds according to claim 1, characterized in that, The first airway (172) is connected to the main airway (15) through the second airway (162).

3. The nested partitioned vacuum insert for film-coated injection molds according to claim 1, characterized in that, The positions of the air inlets of the first air extraction gap (171) and the second air extraction gap (161) correspond to different positions within the cavity (6).

4. The nested partitioned vacuum control insert for film-coated injection molds according to claim 1, characterized in that, The first air extraction gap (171) and the second air extraction gap (161) are distributed from the outside to the inside on the insert body.

5. The nested partitioned vacuum control insert for film-coated injection molds according to claim 1, characterized in that, The insert body is configured as multiple; The first air extraction gap (171) and the second air extraction gap (161) on the multiple insert bodies correspond to different positions within the cavity (6).

6. The nested partitioned vacuum insert for film-coated injection molds according to claim 5, characterized in that, Multiple insert bodies are arranged along the length or width of the mold core side mold (4).

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