A method for injection molding inner wall coating of a barrel-shaped structure

Abstract

This solution discloses a method for injection molding a membrane coating on the inner wall of a barrel-shaped structure. The manufacturing steps include: S1, membrane pretreatment and positioning, where the bottom membrane is tightly fitted to the front end of the stamping head and its position corresponds to the subsequent side membrane bonding position; the corresponding side membrane sheet is unfolded and laid flat in the positioning groove of the worktable; S2, membrane forming based on an inner wall coating injection molding die, where the side membrane is first stamped to initially shape the contour, and then extruded by the mold clamping assembly to form an integral membrane; S3, in-mold injection molding coating based on IML process; S4, finished product removal. This solution, based on the combination of membrane forming process and IML in-mold injection molding technology, achieves precise docking and sealed connection between the bottom and side membranes. The integrated membrane structure has high compatibility with the inner wall of the barrel-shaped structure, effectively avoiding problems such as membrane misalignment and wrinkles in traditional post-processing coating.

Description

Technical Field

[0001] This solution relates to the field of injection molding technology, and in particular to a method for coating the inner wall of a barrel-shaped structure using injection molding. Background Technology

[0002] In recent years, barrel-shaped structures have been widely used in many fields such as chemical, food, medicine, and electronic communications. In order to improve the corrosion resistance, wear resistance, sealing performance, or to achieve specific functions (such as anti-adhesion and antibacterial properties, especially in the field of electronic communications, where it is necessary to integrate the antenna diaphragm or printed diaphragm with the barrel-shaped plastic structure to ensure the accuracy of antenna reflection), it is usually necessary to coat the inner wall of the barrel-shaped structure.

[0003] In existing technologies, the common process of coating the inner wall of barrel-shaped structures often involves first injection molding the barrel body, and then attaching the membrane structure to the inner wall of the barrel through a secondary lamination process. However, this processing method has obvious drawbacks: adding the membrane structure can easily lead to poor overall air permeability and unsatisfactory performance; the secondary lamination process is cumbersome and inefficient, and problems such as membrane structure misalignment and wrinkles can easily occur during the lamination process, affecting the coating accuracy. If applied to antenna diaphragms or printed diaphragms, it can lead to loose bonding and positioning deviation between the diaphragm and the plastic structural components, thus affecting the accuracy of antenna reflection; the bonding strength between the membrane structure and the barrel's plastic structure is insufficient, and the membrane layer is prone to peeling off during long-term use; in traditional coating processes, the positioning and calibration steps of the diaphragm are complex, requiring multiple adjustments to the positioning, which leads to a longer processing cycle and increased production costs.

[0004] In-mold molding (IMM) coating technology, as an integrated coating technique, enables the simultaneous molding and bonding of membrane and plastic structures, effectively improving bonding strength. When applied to antenna diaphragms or printed films, it avoids positioning deviations caused by secondary lamination, ensuring precise bonding between the diaphragm and the plastic structural component, thereby improving antenna reflection accuracy. However, when applying IML technology to the inner walls of barrel-shaped structures, the unique shape of the inner wall makes it difficult to guarantee the pre-forming, precise positioning, and compatibility with the injection mold. This is especially true for membrane materials like antenna diaphragms or printed films, which require higher positioning accuracy and bonding strength. Existing processes cannot meet these requirements, limiting their widespread application in the coating of inner walls of barrel-shaped structures and in related products in the electronic communication field.

[0005] Therefore, there is a need for an injection molding method for coating the inner wall of a barrel-shaped structure, which can achieve efficient, precise, and high-strength coating, and is suitable for antenna diaphragm or printed diaphragm processing, thereby improving the accuracy of antenna reflection and meeting the high-quality requirements of various fields for barrel-shaped structure coating. Summary of the Invention

[0006] To address the aforementioned issues, this solution provides a method for injection molding a membrane coating on the inner wall of a barrel-shaped structure.

[0007] To achieve the above objectives, the technical solution adopted in this paper is: a method for injection molding a membrane coating on the inner wall of a barrel-shaped structure, the manufacturing steps of which include: S1. Diaphragm pretreatment and positioning, wherein the bottom film is tightly attached to the front end of the punching head and its position corresponds to the subsequent side film bonding position. The sheet corresponding to the side film is unfolded and laid flat in the positioning groove of the worktable. S2. The diaphragm is formed based on the inner wall film-coated injection molding die. The side film is first stamped to initially shape the contour, and then the diaphragm is formed by extrusion through the mold assembly. S3. Complete in-mold injection molding coating based on IML process; S4. Remove the finished product.

[0008] Furthermore, S2. After the stamping head contacts the side film sheet in the positioning groove, it continues to press down, and the sheet is initially shaped along the outline of the stamping groove to complete the pre-forming.

[0009] Furthermore, S2 The extrusion block of the mold clamping assembly is controlled to move towards the stamping groove. After the extrusion block is in place, the preformed side film is finally formed under the joint extrusion action of the inner wall of the stamping groove, the extrusion surface of the extrusion block and the outer peripheral surface of the stamping head.

[0010] Furthermore, In S2, The width of the overlapping connection area formed at the junction of the bottom membrane and the side membrane is 2-3 mm. The width of the overlapping positioning area formed by the overlapping positioning holes on both sides of the side membrane is 5-6mm.

[0011] Furthermore, In S2, The extrusion block of the mold clamping assembly is reset by an elastic element.

[0012] Furthermore, S3. Transfer the integrated membrane structure to the corresponding position in the IML injection mold cavity, and position it by matching the positioning pin in the cavity with its own positioning hole. After the injection mold is closed, molten plastic material is injected. The plastic material is tightly bonded to the outer wall of the integrated membrane structure. After cooling and solidification, a barrel-shaped plastic matrix is ​​formed, and the two are integrated.

[0013] In summary, this solution has the following advantages: This solution combines diaphragm forming technology with IML in-mold injection molding technology, achieving precise docking and sealed connection between the bottom and side membranes. The integrated membrane structure has a high degree of compatibility with the inner wall of the barrel-shaped structure, effectively avoiding problems such as membrane shift and wrinkles in traditional post-processing lamination.

[0014] In this solution, the side film is initially positioned by matching the positioning holes with the positioning protrusions. During the stamping process, the guide pillars and guide sleeves work together to ensure stamping accuracy. The integrated film structure is positioned in the mold by matching the positioning holes with the mold positioning pins. Multi-stage positioning ensures the film coating position and significantly improves the processing accuracy of the product. Attached Figure Description

[0015] Figure 1 This is a flowchart of the present invention; Detailed Implementation

[0016] The present solution will be further described below with reference to the accompanying drawings and embodiments: Example 1:

[0017] This embodiment provides an application of a barrel-shaped structure inner wall coating injection molding method in the fabrication of barrel-shaped antenna structures in the field of electronic communications, such as... Figure 1 As shown, the specific production steps are as follows: S1, Membrane Pretreatment The diaphragm is an antenna diaphragm, consisting of a base diaphragm and side diaphragms. Each side diaphragm has six 3mm diameter positioning holes on both sides. The sheet corresponding to the side diaphragm is unfolded and placed flat in the positioning groove of the worktable. The initial precise positioning of the sheet is achieved by matching the positioning holes on both sides of the side diaphragm with the positioning protrusions in the positioning groove. Simultaneously, the base diaphragm is pre-attached to the front end of the stamping head via adhesive bonding, ensuring a tight fit between the base diaphragm and the front end of the stamping head, and that the position of the base diaphragm corresponds to its subsequent bonding position with the side diaphragm after forming.

[0018] S2, The diaphragm is formed using an injection mold with an inner wall coating. Start the stamping equipment. The stamping equipment drives the mounting seat of the displacement part and the stamping head to move towards the fixed part. During this process, the guide post on the mounting seat slides along the guide sleeve on the worktable of the fixed part to achieve smooth and precise movement of the displacement part. When the stamping head moves to contact the side film sheet in the positioning groove, it continues to press down the sheet. Under the stamping action of the stamping head, the sheet is initially shaped along the contour of the stamping groove to complete the pre-forming of the film.

[0019] The extrusion block of the mold clamping assembly is moved toward the stamping groove. The displacement power of the extrusion block is provided by an external power device, which can control the closing by an external power source such as a linear motor or cylinder. In this embodiment, the output end of the cylinder is facing the extrusion block, controlling the extrusion block to move toward the stamping groove.

[0020] When the extrusion block is displaced to its maximum stroke, the pre-formed side film sheet is finally formed under the combined extrusion action of the inner wall of the stamping groove, the extrusion surface of the extrusion block and the outer peripheral surface of the stamping head, forming a side film shape that fits the inner wall of the barrel structure. During this process, the bottom film and the side film attached to the front end of the stamping head form an overlapping area of ​​2-3mm, realizing the integrated connection of the bottom film and the side film. At the same time, the positioning holes on both sides of the side film overlap to form an overlapping area of ​​5-6mm. After forming, an integrated membrane structure that fits the inner wall of the barrel-shaped structure is obtained.

[0021] In this embodiment, the junction of the bottom film and the side film attached to the front end of the stamping head forms an overlapping area with a width of 3mm, and the positioning holes on both sides of the side film overlap to form an overlapping area with a width of 5mm.

[0022] S3. In-mold injection molding coating based on IML process. The extrusion block is provided with reset power through an elastic element. In this embodiment, one end of the spring is connected to the back of the extrusion block, and the other end is fixed to the edge of the worktable. When the thrust disappears, the spring retracts and drives the extrusion block to reset.

[0023] A vacuum adsorption device is used to adsorb the edge of the integrated membrane structure and remove it smoothly from the stamping head, avoiding damage to the surface of the membrane structure. The removed integrated membrane structure is then transferred to the corresponding position in the cavity of the IML injection mold, so that the positioning holes of the integrated membrane structure itself are matched with the positioning pins in the cavity, achieving precise positioning of the integrated membrane structure and the injection mold.

[0024] Subsequently, the injection mold is closed, and molten plastic raw material is injected into the mold cavity. The melt temperature and mold temperature must match the heat resistance temperature of the film (PET / PC) and the molding temperature of the substrate. The plastic raw material fills and forms in the mold cavity, while being tightly bonded to the outer wall of the integrated film structure. After the plastic raw material cools and solidifies, a barrel-shaped plastic substrate is formed. The integrated film structure and the barrel-shaped plastic substrate are integrated, completing the film injection molding of the inner wall of the barrel-shaped structure.

[0025] S4. Finished product removal After injection molding is completed, the IML injection mold is opened, and the finished barrel-shaped antenna structure is removed, completing the entire film-coating injection molding process.

[0026] In summary, this application, based on the combination of diaphragm forming technology and IML in-mold injection molding technology, achieves precise docking and sealed connection between the bottom membrane and the side membrane. The integrated membrane structure has a high degree of compatibility with the inner wall of the barrel structure, effectively avoiding problems such as membrane shift and wrinkles in traditional post-processing lamination.

[0027] The side film of this application achieves initial positioning by matching the positioning hole with the positioning protrusion. During the stamping process, the guide post and guide sleeve cooperate to ensure the stamping accuracy. The integrated film structure achieves in-mold positioning by matching the positioning hole with the mold positioning pin. Multi-stage positioning ensures the film coating position, which significantly improves the processing accuracy of the product.

[0028] The above embodiments are only for illustrating the technical concept and features of this solution, and are intended to enable those skilled in the art to understand the content of this solution and implement it accordingly. They should not be used to limit the scope of protection of this solution. All equivalent transformations or modifications made in accordance with the spirit and essence of this solution should be included within the scope of protection of this solution.

[0029] In the description of this solution, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation", "connection" and "connection" should be interpreted broadly. For example, they can be fixed connections, detachable connections, or integral connections; they can be mechanical connections or electrical connections; they can be direct connections or indirect connections through an intermediate medium; and they can be internal connections between two components.

[0030] Those skilled in the art can understand the specific meaning of the above terms in this solution based on the specific circumstances.

[0031] It should be understood that the above-described embodiments are merely exemplary and not restrictive. Any obvious or equivalent modifications or substitutions made by those skilled in the art regarding the above details without departing from the basic principles of this solution will be included within the scope of protection of this solution.

Claims

1. A method for injection molding a membrane coating on the inner wall of a barrel-shaped structure, characterized in that, The production steps include: S1. Diaphragm pretreatment and positioning, wherein the bottom film is tightly attached to the front end of the punching head and its position corresponds to the subsequent side film bonding position. The sheet corresponding to the side film is unfolded and laid flat in the positioning groove of the worktable. S2. The diaphragm is formed based on the inner wall film-coated injection molding die. The side film is first stamped to initially shape the contour, and then the diaphragm is formed by extrusion through the mold assembly. S3. Complete in-mold injection molding coating based on IML process; S4. Remove the finished product.

2. The injection molding method for coating the inner wall of a barrel-shaped structure according to claim 1, characterized in that, S2. After the stamping head contacts the side film sheet in the positioning groove, it continues to press down, and the sheet is initially shaped along the outline of the stamping groove to complete the pre-forming.

3. The injection molding method for coating the inner wall of a barrel-shaped structure according to claim 2, characterized in that, S2 The extrusion block of the mold clamping assembly is controlled to move towards the stamping groove. After the extrusion block is in place, the preformed side film is finally formed under the joint extrusion action of the inner wall of the stamping groove, the extrusion surface of the extrusion block and the outer peripheral surface of the stamping head.

4. The injection molding method for coating the inner wall of a barrel-shaped structure according to claim 3, characterized in that, In S2, The width of the overlapping connection area formed at the junction of the bottom membrane and the side membrane is 2-3 mm. The width of the overlapping positioning area formed by the overlapping positioning holes on both sides of the side membrane is 5-6mm.

5. The injection molding method for coating the inner wall of a barrel-shaped structure according to claim 4, characterized in that, In S2, The extrusion block of the mold clamping assembly is reset by an elastic element.

6. The injection molding method for coating the inner wall of a barrel-shaped structure according to claim 1, characterized in that, S3. Transfer the integrated membrane structure to the corresponding position in the IML injection mold cavity, and position it by matching the positioning pin in the cavity with its own positioning hole. After the injection mold is closed, molten plastic material is injected. The plastic material is tightly bonded to the outer wall of the integrated membrane structure. After cooling and solidification, a barrel-shaped plastic matrix is ​​formed, and the two are integrated.

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