Gel earmuff sponge assembling and manufacturing process

Abstract

The invention discloses a gel earmuff sponge assembling and manufacturing process, and relates to the technical field of earmuff production, and the gel earmuff sponge assembling and manufacturing process comprises the steps of material preparation, surface skin treatment, surface and bottom skin assembling, sponge and TPU assembling, subsequent assembling and forming, detection and packaging. During material preparation, raw materials are strictly detected, and bottom leather is formed; the wrapper is precisely processed through multiple steps of rubberizing, dispensing and gelling, baking and cooling and the like; the surface leather and the bottom leather are connected through high-cycle welding; specific process parameters and quality standards are set for assembly of all the assemblies and subsequent procedures, and finally the product quality is ensured through visual inspection and QC detection. Compared with the prior art, the production process has the advantages that the whole process flow is optimized, key process quality control and automatic operation are strengthened, the problems of poor assembly adaptability, unstable product performance and the like are effectively solved, the production efficiency is improved, the product consistency is enhanced, and the production requirement of the market for high-quality gel earmuffs is met.

Description

Technical Field

[0001] The present invention relates to the technical field of earmuff production, and in particular to a gel earmuff sponge assembly and manufacturing process. Background Art

[0002] In the field of earmuffs, gel earmuffs are increasingly used due to their advantages such as comfortable fit, shock absorption and sound insulation. However, the existing assembly and manufacturing process of gel earmuff sponges has many shortcomings, such as: There is a lack of precise coordination in the process connection, and the quality control of key links (such as welding of the surface and bottom skins, and component hanging holes) is extensive, which can easily lead to poor component adaptability and low yield rate; production efficiency is limited by equipment debugging and manual operation deviations, and it is difficult to meet the market demand for high-quality, large-scale mass production; at the same time, traditional processes do not make full use of material properties (such as gel curing and PU molding), which can easily cause problems such as colloid cracking and structural loosening, affecting the performance and service life of the earmuffs; therefore, there is an urgent need to optimize the manufacturing process, strengthen process quality control, and improve product consistency and production efficiency to adapt to industry development and market demand for high-quality earmuffs. Summary of the Invention

[0003] In order to solve the technical problems existing in the background technology, the present invention proposes a gel earmuff sponge assembly and manufacturing process.

[0004] The present invention provides a gel earmuff sponge assembly and manufacturing process, comprising: Material preparation: prepare top layer PU, double-sided tape, gel material, bottom layer PU, sponge, TPU, EVA coated with double-sided tape and PETG, and conduct testing; Bottom leather molding: Processing and shaping the bottom leather PU; Dough processing: Dough PU is sequentially pasted with double-sided tape, dispensed with gel, baked and cooled, assembled with jigs, and baked and cooled again to form; Surface and bottom skin assembly: connect or cut off the surface and bottom skin by high frequency welding; Sponge and TPU assembly: complete sponge assembly and TPU and bottom leather hanging holes; Subsequent assembly: high-pressure pressing of PETG, pasting of EVA, punching of outer frame, shaping and ironing; Inspection: including visual inspection and QC sampling inspection; Packaging: Packed with protective materials and marked with information.

[0005] Furthermore, in the material preparation process, the raw materials are visually inspected and measured with measuring tools to check the appearance integrity and specification compliance, and qualified materials are screened and stored in categories.

[0006] Furthermore, in the bottom skin forming process, a customized mold is used, and the bottom skin is shaped by controlling the pressure to 3-5MPa, the temperature to 60-80°C, and the time to 10-15s. After forming, the dimensional accuracy is tested with a two-dimensional measuring instrument.

[0007] Furthermore, in the glue dispensing step of the dough processing process, the evenly mixed gel material is accurately coated with a glue dispensing pressure of 0.3-0.5MPa and a speed of 10-15mm / s. The glue dispensing trajectory and amount are monitored by a visual system, and deviations exceeding the threshold are automatically corrected.

[0008] Furthermore, the high-frequency welding in the face and bottom skin assembly process is set at a frequency of 27.12MHz and a power of 1-3kW, and a high-frequency electric field is used to melt and combine the surface molecules of the face and bottom skin. After welding, the sampling is judged to have a tensile force of ≥50N as the strength qualification standard.

[0009] Furthermore, in the assembly process of the sponge and TPU, the sponge assembly is coordinated with the positioning structure to control the assembly position deviation to be ≤±0.3mm; the TPU and bottom skin hanging holes are processed by CNC equipment, with a hole position deviation of ≤0.2mm and a hole diameter tolerance of ±0.1mm. After the holes are processed, optical inspection is performed to screen out defective ones.

[0010] Furthermore, the parameters of the high-pressure pressing of PETG in the subsequent assembly process are set to pressure 2-4 MPa, temperature 50-70° C., and time 5-8 s. Through the synergistic effect of pressure and temperature, the PETG and the components are stably combined.

[0011] Furthermore, in the inspection process, visual inspection covers product appearance defects and component assembly status; QC inspection uses 5%-10% sampling to inspect key dimensions, bonding strength and sealing, and determines eligibility based on preset standards.

[0012] Furthermore, in the shaping and ironing process, temperature-controlled molds and ironing equipment are used to correct the deformation of the earmuffs and improve the smoothness of the appearance. After shaping, the dimensional consistency is verified by a three-coordinate measuring instrument.

[0013] Furthermore, the packaging process uses cushioning and protective materials, packages in fixed quantities, and labels information such as product name, batch, and production date to facilitate identification and traceability in warehousing and logistics.

[0014] The beneficial effects of this invention include systematic optimization of each step in the gel earmuff sponge assembly and manufacturing process, innovatively employing a multi-step collaborative control and precise quality control strategy. Strict process parameters and quality standards are set throughout the entire process, from raw material testing to finished product packaging. Automation and precision control are strengthened in key processes such as top and bottom skin welding and component hanging holes, effectively addressing the poor component compatibility and unstable product performance issues inherent in existing processes. Furthermore, the optimized process flow reduces material flow losses, improves production efficiency, and significantly enhances product consistency through standardized operations and a traceable quality control system, better meeting market demand for high-quality earmuff production. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 It is a process flow chart of the present invention. DETAILED DESCRIPTION

[0016] Reference Figure 1 The present invention proposes a gel earmuff sponge assembly and manufacturing process, which includes the following steps: A. Material preparation process A01-A08), Raw Material Procurement and Inspection: Purchase raw materials such as PU top sheet, double-sided tape, Wackersilgel 612A+B gel, PU bottom sheet, sponge, TPU, EVA double-sided tape, and PETG from qualified suppliers. Upon arrival, verify material specifications (such as the thickness tolerance of ±0.1mm for PU top sheet and the design value of TPU aperture) and appearance integrity through visual inspection (checking for damage and contamination) and measuring tools (such as calipers and micrometers) in accordance with company inspection standards. Qualified materials are classified and stored in the preparation area. Unqualified materials are marked and returned to the supplier. A04.1) Preparation for bottom skin molding: debug the bottom skin molding mold, set the molding pressure to 3-5MPa, temperature to 60-80℃, and time to 10-15s according to the characteristics of the bottom skin PU material; start the molding equipment, feed the bottom skin PU into the mold, and complete A04.1 bottom skin molding; after molding, use a two-dimensional measuring instrument to detect the key dimensions of the bottom skin (such as diameter and curvature), and control the dimensional deviation within ±0.2mm to ensure that the bottom skin is suitable for subsequent assembly.

[0017] B. Assembly process B01) Double-sided tape application for dough: An automated taping machine is used to place the dough PU at the taping station. The machine secures the dough using vacuum suction, while a robotic arm grabs the double-sided tape. A visual positioning system (camera + image processing algorithm) identifies the taping area for the dough, controlling the taping deviation to ≤±0.5mm. During the taping process, the visual system monitors in real time. If the deviation exceeds a threshold (e.g., 0.6mm), the machine automatically issues an alarm and adjusts the taping position to ensure uniform and precise taping. B02) Gel dispensing equipment: Mix Wackersilgel 612A and B components in a 1:1 ratio (adjustable based on actual curing results) in a low-speed blender, then pour into the dispensing machine's storage tank. Set dispensing parameters: pressure 0.3-0.5 MPa, speed 10-15 mm / s, dispensing volume 0.1-0.2 g / cm² (controlled by dispensing time and pressure). The dispensing machine dispenses glue onto the dough sheet with double-sided tape applied, following a pre-set path (e.g., ring or grid) to ensure even coverage of the gel. B03) Gel baking and cooling: After the gel is applied, the dough is transported to the baking equipment through the assembly line. The baking parameters are set as follows: temperature 60-80℃, time 15-20 minutes. After the baking is completed, the dough is transferred to the natural cooling area (ambient temperature 25±5℃, humidity 40%-60%) and left to cool to room temperature (about 20-30 minutes) to allow the gel to initially solidify and form a stable colloidal structure. B04) Dough assembly jig: Using a customized jig (including positioning pins and limit blocks), the cooled dough is placed into the jig manually or by a robotic arm. The jig positioning pins match the preset positioning holes in the dough to ensure a positioning accuracy of ±0.2mm, providing stable support for the subsequent B05 dough baking, cooling and shaping. B05) Dough baking and cooling: After the dough has been assembled with the jig, it is sent to the secondary baking equipment with the following parameters set: temperature 70-90°C, time 10-15 minutes. After baking, it is quickly cooled by the air cooling system (wind speed 2-3m / s) to strengthen the dough shape and the bonding strength of the gel, so that the dimensional tolerance of the dough is controlled within ±0.3mm to meet the assembly requirements of the bottom dough. B06) High-frequency welding / cutting of the top and bottom covers: Debug the high-frequency welding machine and set the parameters: frequency 27.12MHz, power 1-3kW, welding time 1-2s; place the components with the top cover processed and the bottom cover PU (after A04.1 molding) in the welding station and start the equipment; the high-frequency electric field causes the surface molecules of the top and bottom covers to melt rapidly, completing the bonding; simultaneously, the mold blade cuts off the excess edges, achieving an integrated "welding + cutting" process; after welding, sample one piece (1 out of every 20 pieces) and test the weld strength using a tensile testing machine; a tensile strength of 50N or higher is considered acceptable (simulating the actual force of the earmuffs in use to ensure they will not fall off or crack); B07) Sponge assembly / PU cover: A pneumatic robotic arm grasps the sponge and precisely assembles it onto the top and bottom covers using the positioning grooves on the fixture (matching the sponge's shape). The robotic arm pressure is controlled at 0.1-0.2MPa to ensure a tight fit between the sponge and the top and bottom covers, with an assembly position deviation of ≤±0.3mm. CCD visual inspection can be used to verify the assembly effect in real time, and if the deviation exceeds the limit, the equipment will be shut down for adjustment. B08) TPU hanging holes / sole leather hanging holes: Use a CNC punching machine and import the hole coordinate program (hole position deviation ≤ 0.2mm, hole diameter tolerance ±0.1mm). Fix the TPU and bottom leather to the punching station and start the machine to complete the hanging hole processing. After processing, use optical inspection equipment (such as industrial camera + size detection algorithm) to scan the hole position and hole diameter, and automatically screen out defective products with hole position deviation (such as 0.3mm) and hole diameter tolerance (such as +0.2mm) to ensure that the hanging holes are suitable for subsequent assembly. B09) High-pressure lamination of PETG: Debug the high-pressure lamination equipment and set the parameters: pressure 2-4MPa, temperature 50-70°C, time 5-8s; place the PETG and assembled components into the lamination mold and start the equipment; the synergistic effect of pressure and temperature ensures that the PETG is stably bonded to the top and bottom leather, sponge, etc., forming a preliminary structure; after lamination, visually inspect the PETG for bubbles and wrinkles, and mark and isolate defective products; B10) EVA lamination and die-cutting of EVA outer frame: First, use an automatic laminating machine to precisely laminate the EVA covered with double-sided tape in the designated position (lamination deviation ±0.3mm, assisted by a visual positioning system). Then, place the laminated component into a die-cutting die (installed on a punch press), set the die-cutting pressure to 3-5MPa, and die-cut the EVA outer frame. After die-cutting, use a caliper to check the outer frame size (tolerance ±0.2mm) to ensure it is consistent with the design. B11) Shaping / Pressing: Use a shaping mold (heating type, temperature 60-80°C) and ironing equipment (steam or infrared heating) to correct the overall shape and appearance of the earmuffs. During shaping, the mold slowly applies pressure (pressure 0.5-1MPa) to correct the earmuffs' deformation. Ironing uses thermal radiation to evenly heat the earmuffs' surface and eliminate wrinkles. After shaping, use a three-dimensional coordinate measuring machine to inspect key dimensions (such as earmuff height and curvature). The dimensional consistency deviation is ≤0.2mm. B12), visual inspection, QC testing and packaging: B12.1) Visual Inspection: Qualified inspectors shall conduct 100% visual inspection of the earmuffs. Inspection items include: surface scratches (length ≤ 1mm, depth ≤ 0.1mm acceptable), bubbles (diameter ≤ 0.5mm, quantity ≤ 2 / piece), loose components (e.g., sponge offset > 0.4mm), etc. Defective products shall be marked and classified (e.g., rework, scrapping). B12.2) QC inspection and packaging: For earmuffs that have passed QC, protective packaging materials (such as pearl cotton lining + paper box) are used; they are packaged according to the specified quantity (such as 10 pieces / box) and marked with product name, batch, production date, inspector number and other information through an automatic labeling machine; after packaging, they are placed in turnover boxes (lined with cushioning materials) and transported to the finished product warehouse to wait for shipment.

[0018] Explanation of the terms in this implementation: PU surface: Polyurethane, PU surface refers to the polyurethane material used for the surface of earmuffs. It is soft, wear-resistant, and easy to process. It is often used as the outer layer of earmuffs that come into contact with the skin, providing a comfortable touch and appearance support. Wackersilgel612A+B gel: A two-component silicone gel (component A and component B), which can be cured and molded after mixing in the correct proportion. It has the advantages of high elasticity, aging resistance, and good biocompatibility. It is often used in the cushioning and shock-absorbing layer of earmuffs to improve wearing comfort. Bottom PU: Made from the same polyurethane material as the top PU, it serves as the base support structure for the earmuffs. It is typically harder and thicker than the top PU, providing structural stability. It is bonded to the top PU through processes such as high-frequency welding. TPU: Thermoplastic polyurethane elastomer, with high elasticity, wear resistance, and strong weather resistance. It is often used in the structural parts of earmuffs (such as the hanging holes) to provide toughness and support. EVA coated with double-sided tape: EVA is ethylene-vinyl acetate copolymer. Double-sided tape refers to EVA sheets with double-sided tape attached on one or both sides. It is used as a cushioning or sealing component for earmuffs and has both flexibility and adhesion. PETG: Ethylene glycol-modified polyethylene terephthalate, a transparent, impact-resistant thermoplastic plastic, is often used as a protective layer or decorative component of earmuffs to enhance product strength and appearance.

[0019] The above description is only a preferred specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any technician familiar with the technical field, within the technical scope disclosed by the present invention, who makes equivalent replacements or changes based on the technical solution and inventive concept of the present invention, should be covered by the scope of protection of the present invention.

Claims

1. A gel earmuff sponge assembly manufacturing process, characterized in that: include: Material preparation: prepare top layer PU, double-sided tape, gel material, bottom layer PU, sponge, TPU, EVA coated with double-sided tape and PETG, and conduct testing; Bottom leather molding: Processing and shaping the bottom leather PU; Dough processing: Dough PU is sequentially pasted with double-sided tape, dispensed with gel, baked and cooled, assembled with jigs, and baked and cooled again to form; Surface and bottom skin assembly: connect or cut off the surface and bottom skin by high frequency welding; Sponge and TPU assembly: complete sponge assembly and TPU and bottom leather hanging holes; Subsequent assembly: high-pressure pressing of PETG, pasting of EVA, punching of outer frame, shaping and ironing; Inspection: including visual inspection and QC sampling inspection; Packaging: Packed with protective materials and marked with information.

2. The gel earmuff sponge assembly and manufacturing process according to claim 1, characterized in that: During the material preparation process, the raw materials are visually inspected and measured with measuring tools to check the appearance integrity and specification compliance, and qualified materials are screened and stored in categories.

3. The assembly and manufacturing process of the gel earmuff sponge according to claim 1, characterized in that: In the bottom skin forming process, a customized mold is used, and the bottom skin is shaped by controlling the pressure to 3-5MPa, the temperature to 60-80°C, and the time to 10-15s. After forming, the dimensional accuracy is tested with a two-dimensional measuring instrument.

4. The gel earmuff sponge assembly and manufacturing process according to claim 1, characterized in that: In the glue dispensing step of the dough processing process, the evenly mixed gel material is accurately applied with a glue dispensing pressure of 0.3-0.5MPa and a speed of 10-15mm / s. The glue dispensing trajectory and amount are monitored by a visual system, and deviations exceeding the threshold are automatically corrected.

5. The gel earmuff sponge assembly and manufacturing process according to claim 1, characterized in that: The high-frequency welding in the face and bottom skin assembly process is set at a frequency of 27.12MHz and a power of 1-3kW. A high-frequency electric field is used to melt and combine the surface molecules of the face and bottom skins. After welding, sampling is performed with a tensile force ≥50N as the strength qualification standard.

6. The gel earmuff sponge assembly and manufacturing process according to claim 1, characterized in that: In the assembly process of the sponge and TPU, the sponge assembly is coordinated with the positioning structure to control the assembly position deviation to be ≤±0.3mm; the TPU and bottom skin hanging holes are processed by CNC equipment, with the hole position deviation ≤0.2mm and the hole diameter tolerance ±0.1mm. After the holes are processed, optical inspection is performed to screen out defective ones.

7. The gel earmuff sponge assembly and manufacturing process according to claim 1, characterized in that: The parameters of the high-pressure pressing of PETG in the subsequent assembly process are set as pressure 2-4 MPa, temperature 50-70° C., and time 5-8 s. The synergistic effect of pressure and temperature achieves stable bonding between PETG and the component.

8. The gel earmuff sponge assembly and manufacturing process according to claim 1, characterized in that: During the inspection process, visual inspection covers product appearance defects and component assembly status; QC inspection uses 5%-10% sampling to test key dimensions, bonding strength and sealing, and determines eligibility based on preset standards.

9. The gel earmuff sponge assembly and manufacturing process according to claim 1, characterized in that: In the shaping and ironing process, temperature-controlled molds and ironing equipment are used to correct the deformation of the earmuffs and improve the smoothness of the appearance. After shaping, a three-coordinate measuring instrument is used to verify the dimensional consistency.

10. The gel earmuff sponge assembly and manufacturing process according to claim 1, characterized in that: The packaging process uses cushioning and protective materials, packages in fixed quantities, and labels information such as product name, batch, and production date to facilitate identification and traceability in warehousing and logistics.

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