A multi-cavity multi-color forming injection molding process, a forming mold and a product thereof

Abstract

The application provides a multi-cavity multi-color forming injection molding process, a forming mold and a product thereof, and relates to the field of injection molding. A "one-piece runner" is used as a unified carrier and framework for multiple single-color injection molding steps, and is matched with multiple independent molds to successfully break away from the dependence on expensive multi-color injection molding machines or special positioning carriers. The method realizes high simplification of the production link, improves the production efficiency by more than 50%, reduces the cost by more than 50%, and improves the yield rate to more than 99%. A mold for implementing the one-piece forming multi-cavity multi-color injection molding process, the design of the mold system is the basis for the realization of the foregoing process flow; each set of mold is independently responsible for one color, which reduces the complexity and manufacturing cost of a single set of mold; and a one-piece forming multi-cavity multi-color injection molded product produced by the process, the injection molded product has the characteristics of "multi-color integration, no bonding mark and material fusion".

Description

Technical Field

[0001] This application relates to the field of injection molding, and more specifically, to a multi-cavity, multi-color injection molding process, molding die, and related products. Background Technology

[0002] In traditional injection-molded products without paint spraying, achieving multiple color effects is mostly accomplished by disassembling individual parts and gluing them together (or using a snap-fit ​​structure). This assembly process requires a large workforce and is costly.

[0003] In addition, existing multi-color injection molding technologies all rely on dual-injection molding machines or multi-color injection molding machines, or require the use of a positioning carrier (limited by shape conditions) to achieve multi-color multi-cavity molding, which is more complicated to operate and more expensive.

[0004] This invention is an integrated multi-cavity, multi-color molding process with no shape restrictions. It is extremely easy to operate and can obtain the desired multi-color injection molded products at very low cost and high efficiency. Summary of the Invention

[0005] The purpose of this application is to provide a multi-cavity, multi-color injection molding process, molding die, and related products, which can solve the above-mentioned technical problems.

[0006] This application provides a multi-cavity, multi-color injection molding process, including the following steps: S1. First-color injection molded parts and integrated runner molding: Prepare a first mold, the mold cavity design of which matches the shape of the first-color part of the required injection molded product, and includes a runner system for molding the integrated runner; using an injection molding machine, inject the first-color plastic material into the first mold, and mold multiple first-color injection molded parts and an integrated runner connecting all the first-color injection molded parts in one injection molding; after the mold is opened, the main runner of the injection molding machine automatically separates from the integrated runner, and the multiple first-color injection molded parts connected to the integrated runner are automatically ejected as a whole assembly by the ejection mechanism; S2. Molding of the second-color injection molded part: The integral component obtained in step S1 is placed into the second mold by a robot or manually. The cavity of the second mold is designed to form the second-color part in a specific area of ​​the first-color injection molded part. Using an injection molding machine, the second-color plastic material is injected, so that the second-color material is formed on the first-color injection molded part, thereby forming a composite injection molded part containing the first and second colors. The second-color material simultaneously covers or connects to the integral runner, allowing the integral runner to continue. After the mold is opened, the main runner automatically separates from the integral runner again, and the updated integral component is automatically ejected. S3. Subsequent multi-color sequential injection molding: Repeat step S2, sequentially placing the overall component obtained in the previous step into the corresponding third, fourth, and Nth sets of molds, and injecting the third, fourth, and Nth colors of plastic material respectively, sequentially molding the third, fourth, and Nth color parts, where N is an integer greater than or equal to 3, representing the total number of colors required; in each injection molding step, the newly injected plastic material is combined with the continuous integrated runner, so that the integrated runner serves as the skeleton structure connecting and supporting all multi-cavity multi-color injection molded parts throughout; S4. Runner Separation and Finished Product Acquisition: After the injection molding steps of all colors are completed, a complete multi-color injection molded part assembly connected to the final integrated runner is obtained; finally, the positioning connection points connecting each injection molded part to the integrated runner are cut off by ultrasonic cutting, mechanical shearing or hot burning, thereby separating individual, complete multi-color injection molded products, while the integrated runner is completely recycled as runner material.

[0007] Preferably, the integrated runner adopts a ring array, rectangular array, or mesh structure design adapted to the mold cavity layout, and its cross-sectional shape is circular, elliptical, or rectangular; the number of positioning connection points is 2 to 4 per injection part; the main runner of the first mold is designed as 2 to 12 groups of "V" shaped or radially arranged gates, and this gate structure enables the main runner and the integrated runner to automatically detach and separate when the mold is opened.

[0008] Preferably, each of the first, second, and Nth sets of molds independently corresponds to a color injection molding, and its mold cavity is precisely processed according to the color area to be formed in the current step; the first, second, and Nth sets of molds include a positioning system, which includes positioning holes, positioning pins, or cavity positioning achieved by relying on the shape of the integral flow channel itself around the mold cavity.

[0009] Preferably, after each injection molding opening in steps S1 to S3, the separation of the main runner and the integrated runner, as well as the ejection of the overall component, are all accomplished by an ejection mechanism, eliminating the need for manual removal. After ejection, the overall component is automatically picked up by a robotic arm and transferred to the mold of the next process or a temporary storage rack.

[0010] A mold for implementing the aforementioned one-piece molding multi-cavity multi-color injection molding process includes: Multiple independent molds, the quantity of which is the same as the required number of injection molding colors N, each mold set includes: The mold base is made of steel or aluminum. The mold core, whose cavity is machined according to the shape of the product part of the corresponding color; An integrated runner forming cavity, designed within the mold core, is used to form an integrated runner that serves as the carrier skeleton. This runner forming cavity matches each other in all sets of molds, ensuring that the runners can be sequentially stacked and formed. The automatic separation main runner system is designed with a "V" shaped or conical material pulling structure, which can automatically disconnect the main runner from the integrated runner when the mold is opened; Ejection mechanism, used to eject multi-cavity products with an integrated flow channel as a whole; A high-precision positioning system ensures that preceding injection molded components can be accurately placed into subsequent molds.

[0011] An integrally molded multi-cavity multi-color injection molded product produced by the process described above is a single solid component formed by sequentially stacking at least two different colored plastic materials in one or more injection cycles, relying on a continuously formed integral runner as a carrier skeleton; the different colored areas on the product are material fusion interfaces with no adhesive marks.

[0012] The beneficial effects of this invention are: This invention provides a multi-cavity, multi-color injection molding process that uses an "integrated runner" as a unified carrier and framework throughout multiple single-color injection molding steps, combined with multiple independent molds, successfully eliminating reliance on expensive multi-color injection molding machines or specific positioning carriers. This method achieves a high degree of simplification in the production process, increasing production efficiency by more than 50%, reducing costs by more than 50%, and raising the yield rate to over 99%. Most importantly, its "integrated runner" design allows the runner material to be 100% recycled and reused as a single, pure material, greatly improving raw material utilization and solving the core pain points of traditional multi-color molding or assembly processes, such as high waste, difficult recycling, high costs, and low efficiency.

[0013] A mold system for implementing the aforementioned integrated multi-cavity, multi-color injection molding process is provided, and its design forms the basis for realizing this process. Each mold independently handles one color, reducing the complexity and manufacturing cost of individual molds. The integrated runner molding cavities matched between molds and the unified high-precision positioning system provide the physical guarantee for continuous molding of the "carrier runner" and precise product positioning. The automatically separating main runner design is a key component for achieving automated production. The entire system works collaboratively, ensuring stable and efficient process operation.

[0014] A one-piece, multi-cavity, multi-color injection molded product produced by the aforementioned process is characterized by "multi-color integration, no adhesive marks, and material fusion," distinguishing it from traditional assembled or painted parts in terms of physical properties and appearance. Furthermore, it indicates its application potential in high-value-added fields such as toys, consumer electronics, automobiles, and home furnishings, highlighting the unique advantages of products produced by this invention in meeting the comprehensive requirements of modern industry for aesthetics, environmental protection, durability, and low cost, thus providing clear protection for its commercialization and market promotion. Attached Figure Description

[0015] To more clearly illustrate the technical solutions of the embodiments of this application, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this application and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0016] Figure 1 This is a schematic diagram of the first mold structure of the present invention; Figure 2 This is a schematic diagram of the second mold structure of the present invention; Figure 3 This is a schematic diagram of the Nth mold structure of the present invention; Figure 4 This is a schematic diagram of the N+1th mold structure of the present invention; Figure 5 This is a schematic diagram of the N+2th mold structure of the present invention; Figure 6 This is a schematic diagram of the overall component formed by the first injection molding of the present invention; Figure 7 This is a schematic diagram of the overall component formed by the second injection molding of the present invention; Figure 8 This is a schematic diagram of the overall component formed by the Nth injection molding of the present invention; Figure 9 This is a schematic diagram of the overall component formed by the N+1th injection molding of the present invention; Figure 10 This is a schematic diagram of the overall component formed by the (N+2)th injection molding of the present invention; Figure 11 This is a schematic diagram of the first injection molding runner structure of the present invention; Figure 12 This is a schematic diagram of the second injection molding flow channel structure of the present invention; Figure 13 This is a schematic diagram of the Nth injection molding flow channel structure of the present invention; Figure 14 This is a schematic diagram of the N+1th injection molding flow channel structure of the present invention; Figure 15 This is a schematic diagram of the N+2th injection molding flow channel structure of the present invention. Detailed Implementation

[0017] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. The components of the embodiments of this application described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0018] Therefore, the following detailed description of the embodiments of this application provided in the accompanying drawings is not intended to limit the scope of the claimed application, but merely to illustrate selected embodiments of the application. All other embodiments obtained by those skilled in the art based on the embodiments of this application without inventive effort are within the scope of protection of this application.

[0019] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0020] In the description of this application, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship commonly used when the product of this application is in use. 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, and therefore should not be construed as a limitation on this application. In addition, the terms "first," "second," and "third," etc., are only used to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0021] Furthermore, terms such as "horizontal," "vertical," and "sag" do not imply that components must be absolutely horizontal or suspended, but rather that they can be slightly tilted. For example, "horizontal" simply means that its direction is more horizontal relative to "vertical," and does not mean that the structure must be completely horizontal, but can be slightly tilted.

[0022] In the description of this application, it should also be noted that, unless otherwise expressly specified and limited, the terms "set up," "install," "connect," and "link" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances. Example

[0023] like Figure 1-15 As shown, a multi-cavity, multi-color injection molding process includes the following steps: S1. First-color injection molded parts and integrated runner molding: Prepare a first mold, the mold cavity design of which matches the shape of the first-color part of the required injection molded product, and includes a runner system for molding the integrated runner; using an injection molding machine, inject the first-color plastic material into the first mold, and mold multiple first-color injection molded parts and an integrated runner connecting all the first-color injection molded parts in one injection molding; after the mold is opened, the main runner of the injection molding machine automatically separates from the integrated runner, and the multiple first-color injection molded parts connected to the integrated runner are automatically ejected as a whole assembly by the ejection mechanism; S2. Molding of the second-color injection molded part: The integral component obtained in step S1 is placed into the second mold by a robot or manually. The cavity of the second mold is designed to form the second-color part in a specific area of ​​the first-color injection molded part. Using an injection molding machine, the second-color plastic material is injected, so that the second-color material is formed on the first-color injection molded part, thereby forming a composite injection molded part containing the first and second colors. The second-color material simultaneously covers or connects to the integral runner, allowing the integral runner to continue. After the mold is opened, the main runner automatically separates from the integral runner again, and the updated integral component is automatically ejected. S3. Subsequent multi-color sequential injection molding: Repeat step S2, sequentially placing the overall component obtained in the previous step into the corresponding third, fourth, and Nth sets of molds, and injecting the third, fourth, and Nth colors of plastic material respectively, sequentially molding the third, fourth, and Nth color parts, where N is an integer greater than or equal to 3, representing the total number of colors required; in each injection molding step, the newly injected plastic material is combined with the continuous integrated runner, so that the integrated runner serves as the skeleton structure connecting and supporting all multi-cavity multi-color injection molded parts throughout; S4. Runner Separation and Finished Product Acquisition: After the injection molding steps of all colors are completed, a complete multi-color injection molded part assembly connected to the final integrated runner is obtained; finally, the positioning connection points connecting each injection molded part to the integrated runner are cut off by ultrasonic cutting, mechanical shearing or hot burning, thereby separating individual, complete multi-color injection molded products, while the integrated runner is completely recycled as runner material.

[0024] This invention employs an "integrated runner" as a unified carrier and framework throughout multiple single-color injection molding steps, combined with multiple independent molds, successfully eliminating reliance on expensive multi-color injection molding machines or specific positioning fixtures. This method achieves a high degree of simplification in the production process, increasing production efficiency by over 50%, reducing costs by over 50%, and raising the yield rate to over 99%. Most importantly, its "integrated runner" design allows the runner material to be 100% recycled and reused as a single, pure material, greatly improving raw material utilization and solving the core pain points of traditional multi-color molding or assembly processes: high waste, difficult recycling, high costs, and low efficiency. In this embodiment, the integrated runner adopts a ring array, rectangular array, or mesh structure design adapted to the mold cavity layout, with a cross-sectional shape of circle, ellipse, or rectangle. The number of positioning connection points is 2 to 4 per injection molded part. The main runner of the first mold is designed as 2 to 12 sets of "V"-shaped or radially arranged gates. This gate structure enables the main runner and integrated runner to automatically detach and separate during mold opening. The mesh structure design ensures the overall structural stability and rigidity of multi-cavity products during multiple transfers and injection processes, preventing deformation or misalignment due to insufficient runner strength. The specific connection point design ensures a firm connection while creating conditions for efficient and clean separation (such as ultrasonic separation). The "V"-shaped or radially arranged main runner and the automatic detachment structure achieve automatic and reliable separation of the runner system during each mold opening. This is a key technical guarantee for achieving fully automated production and eliminating manual intervention in part removal, improving the continuity and stability of production. In this embodiment, each of the first, second, and Nth sets of molds independently corresponds to one color injection molding, and its mold cavity is precisely machined according to the color area to be formed in the current step. The first, second, and Nth sets of molds include a positioning system, which includes positioning holes, positioning pins, or cavity positioning achieved by the shape of the integrated flow channel itself around the mold cavity. This invention ensures high precision and high repeatability of the entire multi-color molding process. By designing an independent mold with a precisely corresponding cavity for each color and ensuring that the positioning systems (such as positioning holes and pins) of all molds are strictly consistent, the components formed in the previous step can be accurately and quickly positioned into the subsequent molds. This effectively avoids defects such as product misalignment, flash, and color difference overflow caused by positioning deviation, which is the key foundation for achieving a high yield rate (above 99%) and also makes it possible to quickly adapt the process to different product designs.

[0025] In this embodiment, after each injection molding opening in steps S1 to S3, the separation of the main runner and the integrated runner, as well as the ejection of the overall component, are all accomplished by an ejection mechanism, eliminating the need for manual part removal. After ejection, the overall component is automatically picked up by a robotic arm and transferred to the mold of the next process or a temporary storage rack. This invention minimizes manual intervention and achieves standardization and efficiency in the production process. Through the continuous design of "automatic separation - automatic ejection - automatic transfer by robotic arm," the efficiency bottlenecks, quality fluctuations, and labor costs caused by the heavy reliance on manual part removal, placement, and alignment in traditional multi-color or assembly processes are eliminated. This is not only a direct means of increasing production efficiency by more than 50%, but also makes it possible to establish a 24-hour continuously operating intelligent production line, significantly reducing production management difficulty and labor costs.

[0026] The number of mold cavities is set according to product size and production rate requirements, and can be 1 out of 2 cavities, 1 out of 4 cavities, 1 out of 8 cavities, 1 out of 16 cavities, 1 out of 32 cavities or more; all mold cavities are interconnected through the integrated flow channel, which not only serves to transport the rubber material, but also acts as a unified carrier and positioning skeleton for all injection molded parts in multiple injection molding processes, ensuring the integrity and positional accuracy of multi-cavity products in multiple molding processes. Example

[0027] like Figure 1-5 As shown, a mold for implementing the one-piece molding multi-cavity multi-color injection molding process includes: Multiple independent molds, the quantity of which is the same as the required number of injection molding colors N, each mold set includes: The mold base is made of steel or aluminum. The mold core, whose cavity is machined according to the shape of the product part of the corresponding color; An integrated runner forming cavity, designed within the mold core, is used to form an integrated runner that serves as the carrier skeleton. This runner forming cavity matches each other in all sets of molds, ensuring that the runners can be sequentially stacked and formed. The automatic separation main runner system is designed with a "V" shaped or conical material pulling structure, which can automatically disconnect the main runner from the integrated runner when the mold is opened; Ejection mechanism, used to eject multi-cavity products with an integrated flow channel as a whole; A high-precision positioning system ensures that preceding injection molded components can be accurately placed into subsequent molds.

[0028] A mold system for implementing the aforementioned integrated multi-cavity, multi-color injection molding process is provided, and its design forms the basis for realizing this process. Each mold independently handles one color, reducing the complexity and manufacturing cost of individual molds. The integrated runner molding cavities matched between molds and the unified high-precision positioning system provide the physical guarantee for continuous molding of the "carrier runner" and precise product positioning. The automatically separating main runner design is a key component for achieving automated production. The entire system works collaboratively, ensuring stable and efficient process operation. Example

[0029] like Figure 6-10 As shown, a one-piece molded multi-cavity multi-color injection molded product produced by the process is a single solid component formed by sequentially stacking at least two different colored plastic materials in one or more injection cycles, relying on a continuously formed integral flow channel as a carrier skeleton; the different colored areas on the product are material fusion interfaces, with no adhesive marks.

[0030] A one-piece, multi-cavity, multi-color injection molded product produced by the aforementioned process is characterized by "multi-color integration, no adhesive marks, and material fusion," distinguishing it from traditional assembled or painted parts in terms of physical properties and appearance. Furthermore, it indicates its application potential in high-value-added fields such as toys, consumer electronics, automobiles, and home furnishings, highlighting the unique advantages of products produced by this invention in meeting the comprehensive requirements of modern industry for aesthetics, environmental protection, durability, and low cost, thus providing clear protection for its commercialization and market promotion.

[0031] The resulting multi-color injection molded products have seamless interfaces between different color parts with clear color boundaries, eliminating the need for subsequent spraying, dyeing, or adhesive assembly. Compared with traditional component bonding processes, the products have higher structural strength, no risk of glue aging or detachment, and better overall appearance.

[0032] The above are merely preferred embodiments of this application and are not intended to limit this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A multi-cavity, multi-color injection molding process, characterized in that, Includes the following steps: S1. First-color injection molded parts and integrated runner molding: Prepare a first mold, the mold cavity design of which matches the shape of the first-color part of the required injection molded product, and includes a runner system for molding the integrated runner; using an injection molding machine, inject the first-color plastic material into the first mold, and mold multiple first-color injection molded parts and an integrated runner connecting all the first-color injection molded parts in one injection molding; after the mold is opened, the main runner of the injection molding machine automatically separates from the integrated runner, and the multiple first-color injection molded parts connected to the integrated runner are automatically ejected as a whole assembly by the ejection mechanism; S2, Second color injection molding: The integral component obtained in step S1 is placed into the second set of molds by means of a robot or manual means. The mold cavity of the second set of molds is designed to form the second color part in a specific area of ​​the first color injection mold. Using an injection molding machine, a second color plastic material is injected, causing the second color material to be molded on the first color injection molded part, thereby forming a composite injection molded part containing the first and second colors. The second color material also covers or connects to the integrated runner, allowing the integrated runner to continue. After the mold is opened, the main runner automatically separates from the integrated runner again, and the updated overall component is automatically ejected. S3. Subsequent multi-color sequential injection molding: Repeat step S2, sequentially placing the overall component obtained in the previous step into the corresponding third, fourth, and Nth sets of molds, and injecting the third, fourth, and Nth colors of plastic material respectively, sequentially molding the third, fourth, and Nth color parts, where N is an integer greater than or equal to 3, representing the total number of colors required; in each injection molding step, the newly injected plastic material is combined with the continuous integrated runner, so that the integrated runner serves as the skeleton structure connecting and supporting all multi-cavity multi-color injection molded parts throughout; S4. Runner Separation and Finished Product Acquisition: After the injection molding steps of all colors are completed, a complete multi-color injection molded part assembly connected to the final integrated runner is obtained; finally, the positioning connection points connecting each injection molded part to the integrated runner are cut off by ultrasonic cutting, mechanical shearing or hot burning, thereby separating individual, complete multi-color injection molded products, while the integrated runner is completely recycled as runner material.

2. The multi-cavity, multi-color injection molding process according to claim 1, characterized in that, The integrated runner adopts a ring array, rectangular array, or mesh structure design adapted to the mold cavity layout, and its cross-sectional shape is circular, elliptical, or rectangular; the number of positioning connection points is 2 to 4 per injection part; the main runner of the first mold is designed as 2 to 12 groups of "V" shaped or radially arranged gates, and this gate structure enables the main runner and the integrated runner to automatically detach and separate when the mold is opened.

3. The multi-cavity, multi-color injection molding process according to claim 1, characterized in that, The first set, the second set, and so on up to the Nth set of molds, each set of molds independently corresponds to a color injection, and its mold cavity is precisely processed according to the color area to be formed in the current step; the first set, the second set, and so on up to the Nth set of molds include a positioning system, the positioning system includes positioning holes, positioning pins, or cavity positioning achieved by relying on the shape of the integrated flow channel itself around the mold cavity.

4. The multi-cavity, multi-color injection molding process according to claim 1, characterized in that, After each injection molding opening in steps S1 to S3, the separation of the main runner and the integrated runner, as well as the ejection of the overall component, are all accomplished by the ejection mechanism, eliminating the need for manual removal. After ejection, the overall component is automatically picked up by a robot and transferred to the mold of the next process or a temporary storage rack.

5. A mold for implementing the one-piece molding multi-cavity multi-color injection molding process according to any one of claims 1 to 4, characterized in that, include: Multiple independent molds, the quantity of which is the same as the required number of injection molding colors N, each mold set includes: The mold base is made of steel or aluminum. The mold core, whose cavity is machined according to the shape of the product part of the corresponding color; An integrated runner forming cavity, designed within the mold core, is used to form an integrated runner that serves as the carrier skeleton. This runner forming cavity matches each other in all sets of molds, ensuring that the runners can be sequentially stacked and formed. The automatic separation main runner system is designed with a "V" shaped or conical material pulling structure, which can automatically disconnect the main runner from the integrated runner when the mold is opened; Ejection mechanism, used to eject multi-cavity products with an integrated flow channel as a whole; A high-precision positioning system ensures that preceding injection molded components can be accurately placed into subsequent molds.

6. A one-piece molded multi-cavity, multi-color injection molded product manufactured according to any one of claims 1 to 4, characterized in that: This product is a single solid component formed by sequentially stacking at least two different colored plastic materials in one or more injection molding cycles, relying on a continuously formed integral runner as the carrier skeleton; the different colored areas on the product are material fusion interfaces, with no adhesive marks.

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