A sewing process for detachable inner liner of down jacket

Abstract

This invention discloses a process for sewing a detachable lining for a down jacket. Step 1: Sewing the lining body, with an accommodating space between the first and second fabric layers, and a third fabric layer sewn in a staggered manner between these spaces to form a down-filling cavity; Step 2: Filling the lining with down, inserting down into the filling cavity, and then sewing the filling cavity closed; Step 3: Zipper sewing, symmetrically sewing one set of zipper straps on the front end of the lining body, symmetrically sewing another set of zipper straps on the inside of the down jacket shell, and sewing fixing loops at the cuffs of the lining body; Step 4: Windproofing, sewing windproof accessories at the collar and hem of the lining body; Step 5: Auxiliary fixing sewing, sewing and installing magnetic buckles at the shoulders, back, and hem of the lining body; This invention achieves rapid, secure, and invisible internal fixation between the lining and the outer shell by employing a multi-layer composite structure, a trapezoidal cross-section down-filling cavity, and differentiated down filling in different zones, through fixing loops and magnetic buckles.

Description

Technical Field

[0001] This invention relates to the field of down jacket technology, and more particularly to a sewing process for a detachable inner lining of a down jacket. Background Technology

[0002] The detachable inner lining of this down jacket is a highly practical design. Through a specific connection system, the down lining is integrated with the outer jacket, offering a flexible experience with multiple wearing options. The outer layer is a windproof and durable jacket-style coat, which can be worn alone for a cool and crisp look. The inner lining is filled with high-loft goose down, providing warmth and lightness when worn alone. Combined, they form a super-insulating combination, suitable for extremely cold environments. One garment meets multiple needs, saving space and budget. This three-in-one concept greatly improves the utilization rate of the garment. Wear only the inner lining when it's slightly cool in spring, wear the outer coat alone during transitional seasons, and wear both inner and outer layers together in cold weather—truly suitable for all seasons. This design not only saves on purchase costs but also reduces clothing clutter, making it especially suitable for families who want to simplify the dressing process. Its practicality far exceeds that of ordinary down jackets. Currently, most detachable down linings on the market use simple zippers or buttons for connection, which suffers from problems such as easy displacement of the lining, uneven warmth retention, and inconvenience in disassembly. Especially when the lining is not securely connected to the outer jacket, it is prone to rotation or slippage during wear, affecting comfort. Furthermore, traditional down linings often have a flat filling cavity design, resulting in uneven down distribution, which can create cold spots and reduce warmth retention. Therefore, this invention proposes a sewing process for detachable down linings to solve the problems existing in the prior art. Summary of the Invention

[0003] To address the aforementioned problems, the present invention aims to propose a sewing process for a detachable down jacket lining. This process effectively solves the problems of uneven down distribution, cold spots, and down leakage that exist in traditional detachable down jacket linings by employing a multi-layer composite structure, a trapezoidal cross-section down filling cavity, and zoned differentiated down filling. Furthermore, by using a fixing collar and magnetic buckle, a quick, secure, and invisible internal fixation between the lining and the outer shell is achieved, thus resolving the issue of easy displacement of the lining in traditional detachable down jacket linings.

[0004] To achieve the objectives of this invention, the invention is implemented through the following technical solution: a process for sewing a detachable inner lining for a down jacket, comprising the following steps: Step 1: Sewing the inner lining body. The inner lining body is sewn with a multi-layered fabric structure. There is an accommodating space between the first and second fabric layers. A third fabric layer is sewn in a staggered manner between the accommodating spaces to form a down filling cavity. Step 2: Fill the inner lining with down. Fill the filling cavities with down, and fill each filling cavity with a fixed amount of down. After filling, suture the filling cavities closed. Step 3: Zipper sewing. Sew one set of zipper straps symmetrically on the front of the inner lining body, and sew another set of zipper straps symmetrically on the inside of the down jacket shell. Sew fixing loops on the cuffs of the inner lining body. Step 4: Windproofing. Sew windproof accessories onto the neckline and hem of the inner liner body to seal the gap between the inner liner body and the outer shell. Step 5: Assist in securing the sewing by sewing magnetic snaps onto the shoulders, back, and hem of the inner liner body.

[0005] A further improvement is made in that: a sweat-absorbing layer is attached to the inner side of the first fabric layer in step one, a wear-resistant layer is attached to the outer side of the second fabric layer, and an anti-stick layer is attached to the inner side of the first and second fabric layers, wherein the anti-stick layer is a conductive PE film.

[0006] A further improvement is that the third fabric layer in step one forms a trapezoidal cross-section filling cavity, with adjacent filling cavities tightly fitted together.

[0007] A further improvement is that: in step one, the third fabric layer is connected to the first and second fabric layers by double stitching with a spacing of 0.5cm, and the inclination angle of the third fabric layer is 60°-80°.

[0008] Further improvements include: in step four, a windproof collar is sewn at the neckline of the inner lining body, a windproof strip is sewn at the hem of the inner lining body, and a warming bag is symmetrically sewn on the front end of the second fabric layer.

[0009] A further improvement is made in the following: during the filling of the inner lining in step two, the filling density of the central filling cavity is 120-150 g / m², and the filling density of the edge cavity is 80-100 g / m². After filling, the filling port is sealed.

[0010] A further improvement is that the magnetic force of the magnetic clasp in step five is 0.8-1.2T.

[0011] The beneficial effects of this invention are as follows: By adopting a multi-layer composite structure, a trapezoidal cross-section down filling cavity, and a zoned differentiated down filling method, this invention effectively solves the problems of uneven down distribution, cold spots, and down leakage that exist in traditional detachable down linings. By using a fixing collar and magnetic buckle, it achieves quick, firm, and invisible internal fixation between the lining and the outer shell, thus solving the problem of easy displacement of the detachable down lining. Attached Figure Description

[0012] Figure 1 This is a flowchart of the steps of the present invention; Figure 2 This is a schematic cross-sectional view of the down filling cavity of the present invention; Figure 3 This is a schematic diagram of the fixing collar snap-fit ​​connection of the present invention. Detailed Implementation

[0013] To enhance understanding of the present invention, the present invention will be further described in detail below with reference to embodiments. These embodiments are only used to explain the present invention and do not constitute a limitation on the scope of protection of the present invention.

[0014] The down jacket liner, a crucial yet often overlooked core layer in modern winter clothing, is valuable because it achieves a perfect balance between extreme lightness and high-efficiency warmth through sophisticated materials science and ergonomic design, completely revolutionizing how people dress in winter. It is usually not a standalone unit, but rather a lightweight insulating component inserted within the down jacket shell or flexibly layered under other outerwear. Its core mission is to lock in body heat while minimizing the bulkiness and restriction of movement caused by clothing.

[0015] In essence, the warmth of a down lining lies in its filling—primarily goose or duck down. Generally, goose down, with its larger clusters and finer fiber structure, offers superior warmth and is considered a higher-quality choice. Key indicators of its insulation performance are down content and loft. The new national standard requires down jackets to have a down content of no less than 50%, while high-quality down linings typically reach 90% or even higher. This ensures a very high proportion of down clusters that actually provide insulation, thus trapping more still air. Loft refers to the volume in cubic inches per ounce of down. Higher loft means a thicker insulating air layer and higher insulation efficiency. A high-quality down lining typically has a loft of at least 600, with high-end products reaching 700, 800, or even 1000. This allows it to provide warmth comparable to heavy clothing while remaining extremely lightweight, maintaining its core even in temperatures as low as 5°C or lower. Besides the filling, the fabric and manufacturing process also determine the performance ceiling of the lining. To prevent fine down fibers from escaping through the fabric gaps, high-end linings use high-density fabrics combined with advanced down-proof technologies, such as a four-layer down-locking structure and German down-proof needle technology, ensuring durability for long-term wear. At the same time, the fabric must also balance windproofness and breathability. Some products use military-grade windproof fabrics or densely woven structures to block cold air penetration, while designs such as underarm breathable mesh promote moisture wicking and keep the wearer feeling dry. Furthermore, water-repellent and anti-static finishing technologies are increasingly becoming standard features to enhance the wearing experience, easily handling static electricity issues in light rain, snow, or dry environments. The versatility of down jacket linings is another major appeal. It's a truly versatile layering item, with virtually unlimited styling possibilities. In the workplace, it can be discreetly worn under shirts and suits, becoming a "secret weapon" for business professionals to maintain a professional image without sacrificing warmth; in leisure time, it can be layered with hoodies and denim jackets to create a layered urban look; for fashion-conscious women, a waist-cinching down liner paired with a dress and boots perfectly blends warmth and elegance; and for outdoor activities, it serves as a professional mid-layer, combined with a windbreaker to create a reliable protective system against harsh weather. Its color options range from classic neutrals like black, white, and gray to beige, pink, and even more vibrant shades to suit different personal styles and styling intentions. Many liners also feature a compressible design, easily rolled up and stored in a bag for quick weather changes, making them highly portable.

[0016] The detachable lining of a down jacket is a sophisticated technology. Its core lies in using movable connecting parts to combine the lining and outer shell into a single unit, while also allowing for easy separation, enabling multiple uses and simplifying cleaning. The sewing process prioritizes the independent construction of the lining itself, typically using high-density down-proof fabric and employing compartmentalized down filling technology to evenly fill and secure the down in specific areas. Fine quilting further prevents down shifting. To enhance the tightness of the fit and prevent slippage, snaps or Velcro are often used for multi-point securing. Some designs also add anti-slip strips to the outer surface of the lining or the bottom of the sleeves to increase friction.

[0017] Based on this, according to Figure 1 , Figure 2 , Figure 3 As shown, this embodiment provides a process for sewing a detachable inner lining for a down jacket, including the following steps: Step 1: Sewing the Inner Liner. The inner lining is constructed using a multi-layered fabric structure. An accommodating space is created between the first and second fabric layers. A third fabric layer, staggered between these spaces, forms the down filling cavity. A sweat-absorbing layer is attached to the inner side of the first fabric layer, and an abrasion-resistant layer is attached to the outer side of the second fabric layer. An anti-stick layer, made of conductive PE film, is attached to the inner sides of both the first and second fabric layers. The third fabric layer forms a trapezoidal down filling cavity, with adjacent cavities tightly fitted together. Double stitching is used between the third fabric layer and the first and second fabric layers, with a spacing of 0.5cm. The third fabric layer has an 80° angle. During sewing, the absorbent layer, first fabric layer, anti-adhesive layer, second fabric layer, and abrasion-resistant layer are first bonded together in sequence to form a basic multi-layered fabric structure. Then, a third fabric layer is sewn in a staggered manner between the first and second fabric layers to form a trapezoidal down-filling cavity. This ensures a more even distribution of down after filling, reducing cold spots. Double seams and a tightly fitted structure greatly enhance the cavity's strength, effectively preventing down from escaping through the seams. The conductive PE film of the anti-adhesive layer prevents down from adhering to the fabric due to static electricity, ensuring smooth filling and a lightweight feel when worn.

[0018] Step Two: Filling the Inner Liner with Down. Down is filled into each filling cavity with a predetermined amount of down. After filling, the filling cavities are sewn shut. The filling density of the central filling cavity is 150g / ㎡, and the edge cavities are 90g / ㎡. After filling, the filling openings are sealed. During filling, down is quantitatively filled into each independent filling cavity according to the preset filling amount, with a higher filling density in the central cavity and a lower filling density in the edge cavities. This differentiated filling by zone ensures stronger warmth in the core insulation area, while maintaining flexibility in the frequently used edge areas, achieving an optimized balance between warmth and mobility. Quantitative filling ensures consistent and stable product quality, and the final tight sealing fundamentally prevents down from escaping during use.

[0019] Step 3: Zipper sewing. Sew one set of zipper straps symmetrically to the front of the inner lining body, and another set of zipper straps symmetrically to the inside of the down jacket outer shell. Sew retaining loops to the cuffs of the inner lining body. The split zipper design allows the inner lining to be easily separated from or attached to the outer shell, greatly facilitating washing, replacement, or flexible layering according to temperature. The retaining loops securely fasten the inner lining cuffs to the outer shell cuffs, preventing the inner lining cuffs from riding up during wear and ensuring overall comfort and warmth.

[0020] Step 4: Windproofing. Windproof accessories are sewn onto the collar and hem of the inner liner to seal the gap between the inner liner and the outer shell. A windproof collar is sewn onto the collar of the inner liner, and a windproof strip is sewn onto the hem of the inner liner. Warm pockets are symmetrically sewn onto the front edge of the second fabric layer. The windproof collar and windproof strips effectively seal the gap between the inner liner and the outer shell, effectively preventing cold air from entering through key areas such as the collar and hem, significantly improving the overall windproof and warmth-retaining performance of the garment. The warm pockets allow users to place hand warmers or other items for additional heating.

[0021] Step 5: Assist with securing the sewing. Sew magnetic snaps onto the shoulders, back, and hem of the inner lining. The magnetic strength of the snaps is 1.1T. Through magnetic attraction, the inner lining is quickly and accurately secured to the outer shell, effectively preventing displacement, twisting, or bunching during wear, ensuring the garment's smoothness, aesthetics, and freedom of movement. Compared to traditional buttons or snaps, magnetic snaps are simpler and faster to operate, provide a secure connection, and offer a superior user experience.

[0022] The detachable lining of this down jacket is constructed using a unique stitching process. First, a base structure is formed by combining a sweat-absorbing layer, an anti-sticking layer, a wear-resistant layer, and inner and outer fabric layers. Then, a series of trapezoidal-section filling cavities are created by stitching a third fabric layer at an angle, staggering the first and second layers. Double stitching reinforces the lining, ensuring even down distribution and preventing down leakage. High-density down is filled into the central cavity of the lining to enhance core warmth, while lower-density down is filled into the peripheral cavities to maintain freedom of movement. The filling opening is immediately sealed after filling to prevent leakage. Next, the lining is connected and secured by sewing a zipper strap on the front of the lining and another zipper strap on the inside of the outer shell, along with cuff securing loops, creating a removable lining structure that can be easily separated and reassembled. Windproof accessories are sewn at the collar and hem to prevent cold air from entering. Finally, strong magnetic snaps are sewn at key points such as the shoulders, back, and hem to achieve a quick, firm, and invisible internal fixation between the inner lining and the outer shell, thus completing the manufacture of a detachable down jacket product that combines excellent windproof and warmth retention, flexible wearing, ease of use, and long-lasting durability.

[0023] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of the invention. Various changes and modifications can be made to the invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of the present invention as claimed. The scope of protection of the present invention is defined by the appended claims and their equivalents.

Claims

1. A process for sewing a detachable inner lining for a down jacket, characterized in that, Includes the following steps: Step 1: Sewing the inner lining body. The inner lining body is sewn with a multi-layered fabric structure. There is an accommodating space between the first and second fabric layers. A third fabric layer is sewn in a staggered manner between the accommodating spaces to form a down filling cavity. Step 2: Fill the inner lining with down. Fill the filling cavities with down, and fill each filling cavity with a fixed amount of down. After filling, suture the filling cavities closed. Step 3: Zipper sewing. Sew one set of zipper straps symmetrically on the front of the inner lining body, and sew another set of zipper straps symmetrically on the inside of the down jacket shell. Sew fixing loops on the cuffs of the inner lining body. Step 4: Windproofing. Sew windproof accessories onto the neckline and hem of the inner liner body to seal the gap between the inner liner body and the outer shell. Step 5: Assist in securing the sewing by sewing magnetic snaps onto the shoulders, back, and hem of the inner liner body.

2. The process for sewing a detachable inner lining for a down jacket according to claim 1, characterized in that: In step one, a sweat-absorbing layer is attached to the inner side of the first fabric layer, a wear-resistant layer is attached to the outer side of the second fabric layer, and an anti-stick layer is attached to the inner side of the first and second fabric layers. The anti-stick layer is a conductive PE film.

3. The process for sewing a detachable inner lining for a down jacket according to claim 1, characterized in that: In step one, the third fabric layer forms a trapezoidal cross-section filling cavity, with adjacent filling cavities tightly fitted together.

4. The process for sewing a detachable inner lining for a down jacket according to claim 1, characterized in that: In step one, the third fabric layer is connected to the first and second fabric layers by double stitching with a spacing of 0.5cm, and the inclination angle of the third fabric is 60°-80°.

5. The process for sewing a detachable inner lining for a down jacket according to claim 1, characterized in that: In step four, a windproof collar is sewn at the neckline of the inner lining body, a windproof strip is sewn at the hem of the inner lining body, and a warm pocket is symmetrically sewn at the front end of the second fabric layer.

6. The process for sewing a detachable inner lining for a down jacket according to claim 1, characterized in that: In step two, when filling the inner lining with down, the filling density of the central down filling cavity is 120-150g / ㎡, and the filling density of the edge cavity is 80-100g / ㎡. After filling, the down filling port is sealed.

7. The process for sewing a detachable inner lining for a down jacket according to claim 1, characterized in that: The magnetic strength of the magnetic clasp in step five is 0.8-1.2T.

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