A process for integrally forming a low-temperature vacuum container sandwich special-purpose insulation by cutting and seaming

Abstract

The application relates to the field of thermal insulation material processing, and discloses a low-temperature vacuum container interlayer special thermal insulation blanket integrated laying, cutting and sewing forming process, which comprises the following steps: single-layer base material is flattened and laid by applying tension, a constraint force is applied layer by layer to position and fix, and a multi-layer material stack is formed in cycles; the material stack is cut under the condition of maintaining the position and fixation, and a thermal insulation blank is obtained; the thermal insulation blank is subjected to overall limiting constraint, and is translated and conveyed to a sewing station under the condition of maintaining the constraint, and the relative stacking position between layers is kept unchanged during the whole process; the thickness information of the thermal insulation blank is obtained, and sewing parameters are adaptively adjusted, and finally, a finished product is output after sewing and shaping. Through layer-by-layer tensioning, locking, cutting under pressure, constraint relay conveying and thickness adaptive sewing, the application solves the problems of wrinkling, slippage, layer dispersion, thick material film tearing and needle skipping of multi-layer flexible thermal insulation material during processing, and realizes lossless manufacturing with high dimensional precision and high yield.

Description

Technical Field

[0001] This invention relates to the field of thermal insulation material processing technology, and in particular to an integrated laying and cutting process for a special thermal insulation blanket for low-temperature vacuum container jacket. Background Technology

[0002] Cryogenic vacuum containers typically employ multilayer insulation technology to block thermal radiation and solid-state heat conduction at lower temperatures. This insulation is primarily composed of alternating layers and stitched together extremely thin, double-sided aluminized polyester films (cryogenic insulation reflectors) and low-area-density alkali-free glass microfiber paper or polyester knitted mesh (cryogenic insulation spacers). These flexible substrates are lightweight, easily curled, and have a low coefficient of dynamic friction between layers, making them prone to deformation and structural instability during industrial molding processes.

[0003] Traditional insulation blanket manufacturing processes often employ a loose, natural stacking method during the material laying stage. Due to residual curling stress from unwinding the film substrate and the tendency to trap fluid air cushions during large-area laying, spontaneous physical wrinkles form on the material surface. As the number of layers increases, the irregular micro-deformation of the bottom layer accumulates and amplifies along the Z-axis, severely compromising the initial overall flatness of the multi-layer stack. In subsequent cutting, facing this loosely packed, irregularly stressed multi-layer stack, the lateral cutting force generated by the cutting tool penetrating the material exceeds the weak static friction at the material interface, directly causing horizontal displacement between layers, resulting in stepped misalignment at the cut ends and film tearing and burrs. Simultaneously, during the translation of the cut insulation blank to the sewing station, the lack of seamless mechanical constraints between stations causes the disordered release of compressive potential energy generated by its own weight and localized compression within the stack. Under the acceleration, deceleration, and translational inertia of the conveying mechanism, the internal substrate is prone to asynchronous relative displacement, ultimately leading to severe delamination.

[0004] Furthermore, when ultra-thick insulation blanks with dozens of layers enter the sewing and shaping process, traditional equipment typically relies on preset fixed processing parameters for mechanical sewing. Faced with flexible stacks of material with a large thickness range, the fixed low-position dead-point presser foot will cause devastating static compression and tangential drag on the easily yielding surface aluminized film during fabric feeding, resulting in large-area tearing and damage to the film. The fixed sewing thread tension is completely unable to compensate for the frictional tension loss when the thread penetrates the multi-layer thick fiber network. When the needle returns, the surface thread relaxes and lags, failing to form a standard thread loop for the rotary hook, frequently causing skipped stitches and thread breakage. As a result, the final insulation blanket product fails to meet the expected standards in terms of dimensional accuracy, surface integrity, and overall mechanical stability. Summary of the Invention

[0005] The purpose of this invention is to provide an integrated laying, cutting, and seam forming process for insulation blankets specifically designed for low-temperature vacuum containers. This process solves the problems of wrinkling during laying, slippage and misalignment during cutting and conveying, and damage to the surface membrane and breakage during high-frequency needle skipping when sewing thick materials in traditional processes for manufacturing multi-layer flexible insulation blankets, which are caused by the low surface density of the material and the small interlayer friction.

[0006] To achieve the above objectives, the present invention provides the following technical solution:

[0007] This invention provides an integrated laying and cutting process for a special insulation blanket for low-temperature vacuum container jackets, employing the following technical solution:

[0008] Tension is applied to a single-layer substrate to flatten it and lay it out.

[0009] Each time a single layer of substrate is laid, a constraint force is applied to the laid substrate to position and fix it.

[0010] Repeat the above actions of flattening, laying, and fixing until the set total number of layers is reached, forming a multi-layer stack of materials.

[0011] While maintaining the multi-layer stack in a fixed position, the multi-layer stack is cut and the waste material is separated to obtain the cut insulated blank.

[0012] Apply an overall limiting constraint to the cut insulation blank, and while maintaining the overall limiting constraint, transfer the cut insulation blank to the sewing station, keeping the relative stacking position between the layers inside the cut insulation blank unchanged throughout the process.

[0013] Obtain the thickness information of the cut insulation blank, adaptively adjust the sewing parameters according to the thickness information, sew and shape it, and output the finished insulation quilt.

[0014] By adopting the above technical solution, this process achieves dimensional accuracy and non-destructive manufacturing of multilayer flexible thermal insulation materials from independent substrates to stitched and shaped finished products. The specific stress control mechanism is explained in the following process steps:

[0015] In the material flattening process, a two-dimensional tension stretching mechanism exists. Tension is applied inward to the surface of a single-layer substrate to bring it to a tensile state before the material yields, physically offsetting the residual curling stress inside the film material.

[0016] During the laying process, there is a Z-axis layer-by-layer locking and degassing mechanism. After each layer is laid, a normal constraint force is immediately applied to establish a physical rigid boundary in the Z-axis direction, compress the gap between adjacent layers, expel the trapped air fluid pad, forcibly solidify the geometric flatness of the current substrate, and block the upward transmission and accumulation path of the micro-deformation of the bottom layer.

[0017] In the cutting process, there exists a high-rigidity boundary shear resistance mechanism. Cutting is performed under closed and compressed conditions where the multi-layer stack of materials is maintained in a fixed position. The increase in normal pressure makes the anti-slip static friction between the material layers much greater than the lateral component force generated when the cutting tool penetrates the material. This forces the cutting edge to cut the interlayer film and fiber structure, which are in a compressed and locked state, in a single plane, eliminating longitudinal buckling and yielding of the material and misalignment of the cutting surface.

[0018] The conveying process involves stress sealing and seamless relay mechanisms. The overall limiting constraints of the pre-intervention transfer mechanism are released from its fixed position, allowing the two sets of physical constraints to overlap temporally at the junction. This operation continuously seals the elastic potential energy stored inside the material stack due to substrate compression, preventing rebound expansion in the Z-axis direction from causing attenuation of interlayer positive pressure. This ensures that the accelerating translational inertial force of the transfer system is always less than the interlayer static frictional resistance of the insulation material, achieving zero relative displacement transfer between layers.

[0019] In the sewing process, there exists a physical volume adaptive mechanical matching mechanism. The actual thickness of the cut insulating blank is used as a feedforward control variable to dynamically change the sewing parameters. By mechanically adjusting the presser foot height to match the material thickness, destructive rigid physical extrusion sources are eliminated.

[0020] The line tension is synchronized to adapt to the frictional resistance of thick material penetration, compensates for the internal tension loss of the line, and ensures that the line loop expands smoothly with the rotary hook by relying on the remaining tension when the needle rises, thus eliminating the mechanical preconditions for needle skipping and film tearing.

[0021] Preferably, the laying and positioning steps further include:

[0022] A mechanical gripper module is used to grasp a single-layer substrate, and a servo drive unit applies a uniformly distributed micro-tension to the surrounding area to flatten the single-layer substrate. The micro-tension is in the range of 0.5 to 2.0 N / m.

[0023] Move the flattened single-layer substrate directly above the spreading platform and lower it for alignment. The lateral movement speed of moving the single-layer substrate directly above the spreading platform is 0.5 to 1.5 m / s, and the slow descent speed of lowering the single-layer substrate for alignment is 0.1 to 0.3 m / s.

[0024] The edge area of ​​the laid substrate is pre-tightened in the Z-axis direction by a limiting clamping mechanism to lock the edge and fix it. The pre-tightening pressure is in the range of 0.02 to 0.08 MPa and the total number of layers is set to be 30 to 70 layers.

[0025] By adopting the above technical solution, the micro-tension of 0.5 to 2.0 N / m is precisely set above the in-plane buckling critical stress and below the tensile limit of the heat insulation reflective screen substrate, so that the material can be purely extended in two dimensions without plastic cracking.

[0026] The slow descent speed of 0.1 to 0.3 m / s offsets the fluid buoyancy formed by trapping air cushions when the substrate falls freely over a large area.

[0027] The pre-tightening pressure of 0.02 to 0.08 MPa provides sufficient Z-axis normal stress, expelling free air while avoiding excessive compression that could damage the microfiber mesh structure of the internal insulation spacers.

[0028] Preferably, the step of cutting the multi-layer stack further includes:

[0029] An external clamping mechanism is used to maintain the multi-layer stack in a fixed position. The conformal pressure applied by the external clamping mechanism in maintaining the fixed position is in the range of 0.10 to 0.15 MPa.

[0030] The CNC cutting system operates within the fixed position of the multi-layer material stack according to the preset two-dimensional contour trajectory. The cutter penetrates the multi-layer material stack in one go. The feed speed of the CNC cutting system is in the range of 1.5 to 4.0 m / min.

[0031] By adopting the above technical solution, a high-order conformal pressure of 0.10 to 0.15 MPa is applied to the outer periphery of the tool running trajectory to further compact the loose fiber spacer layer and establish a high-rigidity force boundary on the inner side of the cutting trajectory.

[0032] A feed rate of 1.5–4.0 m / min is matched with the static friction between the layers formed by the above constraints, enabling the cutting edge to achieve shearing and separation of the material layers, ensuring the macroscopic perpendicularity of the cutting surface and eliminating free burrs.

[0033] Preferably, the steps of applying overall limiting constraints and translational transport further include the following action sequence:

[0034] Before the fixed position is released, the conveying mechanism pre-clamps the cut insulated blank with a covering clamp on both the upper and lower sides, and the relative clamping pressure of the covering clamp is in the range of 0.01 to 0.05 MPa.

[0035] The conveying mechanism moves the cut insulated blanks to the sewing station at a speed of 0.2 to 0.6 m / s.

[0036] By adopting the above technical solution, the pre-clamping operation establishes a seamless relay timing sequence. A covering relative clamping pressure of 0.01–0.05 MPa maintains a constant elastic compressive potential energy within the material stack. A low translational speed of 0.2–0.6 m / s limits the inertial force during equipment acceleration and deceleration. The large-area uniformly distributed normal covering clamping torque is much greater than the tangential sliding torque generated by translation, allowing the insulated billet to function as a physical unit with overall structural rigidity.

[0037] Preferably, the adaptive adjustment and stitch shaping steps further include: sewing parameters including the presser foot distance from the needle plate of the sewing machine head and the tension of the sewing top thread and bottom thread;

[0038] After obtaining the thickness information of the cut insulation blank, adjust the height of the presser foot from the needle plate to 3.0-15.0 mm, and adjust the tension of the sewing thread and the bobbin thread to 1.0-4.0 N;

[0039] The stitching and shaping process includes continuous overlock stitching along the outer edge of the cut insulation blank. The speed of the continuous overlock stitching is 800-1200 rpm and the stitch length is 3.0-5.0 mm.

[0040] And perform array dot stitching on the middle surface of the cut insulation blank. The rotation speed of the array dot stitching is 500-800 rpm, the dot spacing is 150-300 mm, and the stitch distance is 6.0-10.0 mm.

[0041] By adopting the above technical solution, the adaptive presser foot stroke of 3.0 to 15.0 mm fully accommodates the physical thickness variation of 30 to 70 layers of material, so that the bottom surface of the presser foot only provides moderate normal follow-up pressure, avoiding tangential tensile tearing of the surface film by the dead presser foot under the feeding condition.

[0042] The 1.0–4.0N tension adjustment specifically replenishes the normal tension consumed when the suture passes through multiple layers of obstructed environment, maintaining the basic elastic limit required for the needle to form a loop. The two-dimensional combination of continuous overlock stitches around the perimeter and large-stitch dot matrix stitches inside locks in the parallel geometric relationship within multiple layers while reducing the thermal bridging effect caused by suture penetration.

[0043] Preferably, the single-layer substrate consists of alternating cryogenic insulation reflective screens and cryogenic insulation spacers; the cryogenic insulation reflective screen is a double-sided aluminized polyester film with a thickness in the range of 6.0 to 12.0 μm.

[0044] The cryogenic insulation spacer is made of alkali-free glass microfiber paper or polyester knitted mesh with a surface density in the range of 15 to 35 g / m².

[0045] By adopting the above technical solution, a system of alternating thin films and spacer layers with selected thicknesses and densities was constructed to create a core micro-medium that blocks low-temperature thermal radiation and solid-state heat conduction.

[0046] The mechanical intervention parameters for the entire manufacturing process, such as the micro-tension of the fabric, the clamping pressure for shape preservation, and the adaptive sewing matching, are all based on the low tensile yield strength and high porosity compression characteristics exhibited by the dual-substrate structure. Ultimately, this has enabled the industrial production of ultra-thick flexible thermal insulation blankets with low defect rates and high shape accuracy.

[0047] In summary, the present invention has at least one of the following beneficial technical effects:

[0048] 1. This invention applies in-plane tension to a single-layer flexible thermal insulation substrate during the laying process to stretch and flatten it, and immediately applies normal constraint force after each single layer is laid to close and lock it layer by layer. This allows the residual curling stress inside the substrate to be offset and the fluid air cushion trapped between layers to be forcibly discharged. This blocks the path of surface wrinkling and micro-deformation accumulation that is easily caused by traditional natural loose stacking, and improves the overall flatness and forming dimensional accuracy of the multi-layer thermal insulation stack.

[0049] 2. This invention performs the cutting action while maintaining the material stack under pressure and fixation, and applies overall limiting clamping constraints by the conveying mechanism before the fixed state is released for transfer. Therefore, at the cutting node, a rigid boundary is constructed to resist the lateral component of the cutting force by using high normal pressure to eliminate cross-sectional slippage burrs. At the same time, at the translational transfer node, the elastic compressive potential energy inside the material stack is continuously sealed to resist the inertial shear force brought about by the accelerated movement of the equipment. Thus, the non-destructive transfer of the insulated billet with zero relative displacement between layers is realized during the multi-station flow process.

[0050] 3. This invention obtains the actual thickness information of the thick insulation blank before the end stitching and shaping, and uses this as a feedforward variable to adaptively and dynamically adjust the presser foot height and sewing thread tension parameters of the sewing machine head. Therefore, the normal follow-up pressure of the mechanical mechanism can accurately adapt to the dynamic friction characteristics of materials with different layers, thereby eliminating the physical tearing defects of the surface aluminum-coated film caused by the traditional fixed small presser foot parameters forcibly pushing the material. At the same time, it overcomes the puncture resistance of the deep fiber network to solve the problems of high-frequency skipped stitches and thread breakage, and finally ensures the high density and mechanical stability of the multi-layer insulation quilt finished structure. Attached Figure Description

[0051] Figure 1 This is a process flow diagram of the present invention;

[0052] Figure 2 This is a timing diagram of the seamless relay action of the present invention. Detailed Implementation

[0053] To make the technical problems solved, technical solutions, and beneficial effects of this invention clearer, the invention will be further described in detail below with reference to embodiments, comparative examples, and test examples. It should be understood that the specific embodiments described herein are only for explaining the invention and are not intended to limit the invention.

[0054] Example 1:

[0055] See attached document Figure 1 This embodiment provides an integrated laying and cutting process for a special insulation blanket for low-temperature vacuum container sandwich, including the following steps:

[0056] Prepare a single-layer substrate, consisting of alternating layers of cryogenic thermal insulation reflective screens and cryogenic thermal insulation spacers. The cryogenic thermal insulation reflective screens are made of double-sided aluminized polyester film with a thickness of 6.0 μm, and the cryogenic thermal insulation spacers are made of material with an areal density of 15 g / m². 2 Alkali-free glass microfiber paper.

[0057] Laying and positioning steps: A mechanical gripper module is used to grasp a single layer of substrate, and a servo drive unit applies a uniformly distributed micro-tension to the surrounding area to flatten the single layer of substrate. The micro-tension is 0.5 N / m.

[0058] The flattened single-layer substrate is moved to the top of the spreading platform and lowered for alignment. The translation speed is 1.5m / s, and the slow descent speed for alignment is 0.3m / s.

[0059] After each single layer of substrate is laid, a pre-tightening pressure of 0.02 MPa is applied to the edge area of ​​the laid substrate in the Z-axis direction using a limiting and clamping mechanism to achieve positioning and fixation.

[0060] Repeat the above actions of flattening, laying, and positioning until the set total number of layers of 30 is reached, forming a multi-layer stack.

[0061] Steps for cutting multi-layer stacks: Use an external clamping mechanism to keep the multi-layer stack in a fixed position, and apply a conformal pre-compression of 0.10 MPa;

[0062] The CNC cutting system operates within the fixed position of the multi-layer material stack according to the preset two-dimensional contour trajectory. The cutter penetrates the multi-layer material stack in one go. The feed speed of the CNC cutting system is 4.0m / min. The multi-layer material stack is cut and the waste material is separated to obtain the cut insulation blank.

[0063] See attached document Figure 2 The overall limiting constraint and translational conveying steps are as follows: Before the positioning and fixing state is released, the conveying mechanism pre-applies a covering clamp on the upper and lower sides of the cut insulated blank to achieve overall limiting constraint. The relative clamping pressure of the covering clamp is 0.01MPa.

[0064] like Figure 2 The stress closure and seamless relay action sequence shown is divided into three states along the process time evolution axis:

[0065] In state one, the peripheral clamping mechanism continuously applies a normal positioning clamping force;

[0066] When entering state two, while maintaining the fixed external positioning, the conveying mechanism intervenes in advance and performs upper and lower covering clamping. At this time, the working states of the external clamping mechanism and the conveying clamping mechanism form a seamless overlap zone of constraint actions;

[0067] Then, in state three, the outer clamping mechanism is released from its fixed state and exits, while the conveying mechanism maintains the clamping state for horizontal conveying.

[0068] This temporal overlap mechanism continuously seals the elastic compressive potential energy inside the stack at the seamless junction of mechanical constraints, blocking the rebound expansion in the Z-axis direction caused by the constraint gap period, thereby ensuring the lossless transfer of the insulated billet with zero relative displacement between layers during the multi-station transfer process.

[0069] While maintaining overall limiting constraints, the conveying mechanism moves the cut insulation blank horizontally to the sewing station at a speed of 0.6 m / s, keeping the relative stacking position between layers inside the cut insulation blank unchanged throughout the process.

[0070] Adaptive adjustment and sewing shaping steps: Obtain the thickness information of the cut insulation blank, and adaptively adjust the sewing parameters according to the thickness information. Adjust the height of the presser foot of the sewing machine head from the needle plate to 3.0mm, and adjust the tension of the sewing top thread and bottom thread to 1.0N.

[0071] Continuous overlock stitching is performed along the outer edge of the cut insulation blank at a speed of 1200 rpm and a stitch length of 3.0 mm. Array dot stitching is performed on the middle surface of the cut insulation blank at a speed of 800 rpm, a dot spacing of 300 mm, and a stitch length of 10.0 mm.

[0072] After the stitching and shaping are completed, the finished insulation blanket is output.

[0073] Example 2:

[0074] This embodiment provides an integrated laying and cutting process for a special insulation blanket for low-temperature vacuum container sandwich, including the following steps:

[0075] Prepare a single-layer substrate, consisting of alternating layers of cryogenic thermal insulation reflective screens and cryogenic thermal insulation spacers. The cryogenic thermal insulation reflective screens are made of double-sided aluminized polyester film with a thickness of 9.0 μm, and the cryogenic thermal insulation spacers are made of material with an areal density of 25 g / m². 2 Polyester knitted mesh.

[0076] Laying and positioning steps: A mechanical gripper module is used to grasp a single layer of substrate, and a servo drive unit applies a uniformly distributed micro-tension to the surrounding area to flatten the single layer of substrate. The micro-tension is 1.2 N / m.

[0077] The flattened single-layer substrate is moved to the top of the spreading platform and lowered for alignment. The translation speed is 1.0 m / s, and the slow descent speed for alignment is 0.2 m / s.

[0078] After each single layer of substrate is laid, a pre-tightening pressure of 0.05 MPa is applied to the edge area of ​​the laid substrate in the Z-axis direction using a limiting and clamping mechanism to achieve positioning and fixation. The above flattening, laying and positioning and fixing actions are repeated until the set total number of layers of 50 is reached to form a multi-layer stack.

[0079] Steps for cutting multi-layer stacks: Use an external clamping mechanism to keep the multi-layer stack in a fixed position, and apply a conformal pre-compression of 0.12 MPa;

[0080] The CNC cutting system operates within the fixed position of the multi-layer material stack according to the preset two-dimensional contour trajectory. The cutter penetrates the multi-layer material stack in one go. The feed speed of the CNC cutting system is 2.5m / min. The multi-layer material stack is cut and the waste material is separated to obtain the cut insulation blank.

[0081] Applying overall limiting constraints and translational conveying steps: Before the positioning and fixing state is released, the conveying mechanism pre-applies a covering clamp on the upper and lower sides of the cut insulated blank to achieve overall limiting constraints. The relative clamping pressure of the covering clamp is 0.03MPa.

[0082] While maintaining overall limiting constraints, the conveying mechanism translates and transports the cut insulation blank to the sewing station at a speed of 0.4 m / s, keeping the relative stacking position between layers inside the cut insulation blank unchanged throughout the process.

[0083] Adaptive adjustment and sewing shaping steps: Obtain the thickness information of the cut insulation blank, and adaptively adjust the sewing parameters according to the thickness information. Adjust the height of the presser foot of the sewing machine head from the needle plate to 8.0mm, and adjust the tension of the sewing top thread and bottom thread to 2.5N.

[0084] Continuous overlock stitching is performed along the outer edge of the cut insulation blank at a speed of 1000 rpm and a stitch length of 4.0 mm. Array dot stitching is performed on the middle surface of the cut insulation blank at a speed of 650 rpm, a dot spacing of 200 mm, and a stitch length of 8.0 mm.

[0085] After the stitching and shaping are completed, the finished insulation blanket is output.

[0086] Example 3:

[0087] This embodiment provides an integrated laying and cutting process for a special insulation blanket for low-temperature vacuum container sandwich, including the following steps:

[0088] Prepare a single-layer substrate, consisting of alternating layers of cryogenic thermal insulation reflective screens and cryogenic thermal insulation spacers. The cryogenic thermal insulation reflective screens are made of double-sided aluminized polyester film with a thickness of 12.0 μm, and the cryogenic thermal insulation spacers are made of material with an areal density of 35 g / m². 2 Alkali-free glass microfiber paper.

[0089] Laying and positioning steps: A mechanical gripper module is used to grasp a single layer of substrate. A servo drive unit applies a uniformly distributed micro-tension to the surrounding area to flatten the single layer of substrate. The micro-tension is 2.0 N / m. The flattened single layer of substrate is moved to the top of the laying platform and lowered for alignment. The translation speed is 0.5 m / s, and the slow descent speed for alignment is 0.1 m / s. After each layer of substrate is laid, a limiting and clamping mechanism is used to apply pre-tightening pressure to the edge area of ​​the laid substrate in the Z-axis direction to achieve positioning and fixation. The pre-tightening pressure is 0.08 MPa.

[0090] Repeat the above actions of flattening, laying, and positioning until the set total number of layers of 70 is reached, forming a multi-layer stack.

[0091] Steps for cutting multi-layer stacks: Use an external clamping mechanism to keep the multi-layer stack in a fixed position, and apply a conformal pre-compression of 0.15 MPa;

[0092] The CNC cutting system operates within the fixed position of the multi-layer material stack according to the preset two-dimensional contour trajectory. The cutter penetrates the multi-layer material stack in one go. The feed speed of the CNC cutting system is 1.5m / min. The multi-layer material stack is cut and the waste material is separated to obtain the cut insulation blank.

[0093] Applying overall limiting constraints and translational conveying steps: Before the positioning and fixing state is released, the conveying mechanism pre-applies a covering clamp on the upper and lower sides of the cut insulation blank to achieve overall limiting constraints. The relative clamping pressure of the covering clamp is 0.05MPa. Under the condition of maintaining overall limiting constraints, the conveying mechanism translates and conveys the cut insulation blank to the sewing station at a speed of 0.2m / s, keeping the relative stacking position between the layers inside the cut insulation blank unchanged throughout the process.

[0094] Adaptive adjustment and sewing shaping steps: Obtain the thickness information of the cut insulation blank, and adaptively adjust the sewing parameters according to the thickness information. Adjust the height of the presser foot of the sewing machine head from the needle plate to 15.0mm, and adjust the tension of the sewing top thread and bottom thread to 4.0N.

[0095] Continuous overlock stitching is performed along the outer edge of the cut insulation blank at a speed of 800 rpm and a stitch length of 5.0 mm. Array dot stitching is performed on the middle surface of the cut insulation blank at a speed of 500 rpm, a dot spacing of 150 mm, and a stitch length of 6.0 mm.

[0096] After the stitching and shaping are completed, the finished insulation blanket is output.

[0097] Comparative Example 1:

[0098] Compared with Example 2, the difference is that: in the laying and positioning steps, no micro-tension is applied to the single-layer substrate to flatten it, and after each layer is laid, no pre-tightening pressure is applied to the edge of the substrate for positioning and fixing; only natural stacking is performed. The rest are the same.

[0099] Comparative Example 2:

[0100] Compared with Example 2, the difference is that in the step of cutting the multi-layer stack, the outer clamping mechanism is not used to keep the multi-layer stack in a fixed position. Instead, the stack is cut by a cutter in a naturally loose state without any conformal pressure constraint. All other aspects are the same.

[0101] Comparative Example 3:

[0102] Compared with Example 2, the difference is that in the steps of applying overall limiting constraints and translational conveying, the positioning and fixing state of the multi-layer material stack is completely released first, and then the conveying mechanism performs a covering clamping and translational conveying on the cut insulated blank. The action sequence of pre-clamping before the positioning and fixing state is released is not used, but all other steps are the same.

[0103] Comparative Example 4:

[0104] Compared with Example 3, the difference is that in the adaptive adjustment and sewing shaping steps, the sewing parameters are not adaptively adjusted according to the thickness information. Instead, the fixed sewing parameters set for thin materials in Example 1 (i.e., adjusting the height of the presser foot of the sewing machine head from the needle plate to 3.0 mm and adjusting the tension of the sewing top thread and bottom thread to 1.0 N) are used to sew and shape the 70-layer multi-layer material stack. All other aspects are the same.

[0105] Test Example 1:

[0106] The finished insulation blankets prepared in Examples 1 to 3 were laid flat and placed in a constant temperature and humidity environment of 20±2℃ and 50±5% for 24 hours to eliminate residual internal stress in the material during processing.

[0107] The length and width of the finished thermal insulation blanket were measured using an industrial vernier caliper with a measuring range of 2000 mm and a graduation of 0.1 mm. Measurements were taken at three equidistant points along the length of the product: left, center, and right, and the arithmetic mean was calculated.

[0108] Measurements were taken at three equidistant points along the width of the product: top, middle, and bottom, and the arithmetic mean was calculated. The difference between the average length and the average width was calculated and then divided by the nominal design dimension of the batch of products. The absolute values ​​were then divided by the nominal design dimension to obtain the length deviation rate and the width deviation rate.

[0109] The presser foot area is 20cm². 2 The thickness of the insulation blanket was measured using an industrial thickness gauge with a constant pressure of 2 kPa. Five independent test points were selected on the surface of each blanket, at the four corners and the geometric center, and the thickness values ​​at each point were recorded. The difference between the maximum and minimum thickness values ​​at these five test points was calculated and recorded as the thickness range.

[0110] For the production batches of Examples 1 to 3, five finished product samples were randomly selected and the measurement process of steps 2 and 3 above was repeated. The arithmetic mean of the five sets of deviation rates and thickness ranges was calculated and entered into a table as the final test data of this example.

[0111] Table 1. Dimensional accuracy and thickness range test data of the finished products from Examples 1 to 3

[0112] Experimental Groups Total number of insulation layers Length deviation rate (%) Width deviation rate (%) Thickness range (mm) Example 1 30 0.11 0.14 0.32 Example 2 50 0.17 0.15 0.49 Example 3 70 0.23 0.26 0.84

[0113] in conclusion:

[0114] According to the data in Table 1, the length and width deviation rates of the insulation blankets prepared in Examples 1 to 3 were both controlled within 0.30% as the total number of layers increased from 30 to 70, and the maximum thickness difference did not exceed 0.90 mm. This data distribution confirms the effectiveness of the molding process of this invention in the processing of multi-layered materials.

[0115] The thermal insulation reflective screen and spacers are physically thin and prone to electrostatic adsorption. Conventional laying and cutting methods can easily lead to dimensional shrinkage or edge misalignment due to interlayer slippage. This solution applies uniform micro-tension to all sides during the material laying stage using mechanical grippers, overcoming the intrinsic curling stress of the substrate and keeping it flat. Furthermore, a Z-axis pre-tightening pressure is applied after each layer is laid. This coordinated action of layer-by-layer flattening and edge locking solidifies the planar extension state of the membrane material.

[0116] In subsequent processes, the material stack is subjected to through-cutting by the cutting tool while maintaining a fixed position and pressure. Before the outer clamping is released, the station linkage mechanism pre-establishes an upper and lower covering clamp. This seamless stress transfer mechanism ensures that no tangential slippage occurs on the internal stacking layer during the entire process of cutting, shaping, and translating the material stack to the sewing station. The external two-dimensional contour of the finished product strictly adheres to the preset trajectory of the cutting tool, which is reflected in the test data as a low dimensional deviation rate.

[0117] Simultaneously, applying pre-tightening pressure layer by layer eliminates air trapped between layers. Combined with the adaptive adjustment of the presser foot distance from the needle plate and the thread tension at the sewing station based on the material stack thickness, this avoids the localized crowding and dragging deformation that occurs with traditional fixed presser feet on thick materials. The final product exhibits a highly consistent thickness at the five tested locations. The increase in thickness variation with the number of layers is entirely within the material's inherent physical tolerances, proving that this process can stably output multi-layer insulation products with high geometric precision.

[0118] Test Example 2:

[0119] In a standard laboratory environment with a temperature of 23±2℃ and a relative humidity of 50±5%, strip-shaped test samples with a width of 50mm and a length of 200mm were cut from the central area of ​​the insulation blankets prepared in Examples 1 to 3 using a mold. The cutting position must ensure that the middle of the sample contains an array of dotted stitches, and that there are sufficient unstitched areas at both ends for clamping.

[0120] Place the test sample in the upper and lower clamps of the universal testing machine. Adjust the distance between the upper and lower clamps and set the initial gauge length to 100mm to ensure that the clamping force is moderate, so that the sample is in a natural vertical state without obvious sagging. At the same time, reset the sensor reading to zero to avoid applying pre-tension stress to the sample.

[0121] Set the crosshead moving speed of the testing machine to 50 mm / min, and start the instrument to perform longitudinal unidirectional constant speed tensile testing on the test sample.

[0122] Observe the stress process of the sample and record the tensile force and displacement data simultaneously. When the outermost double-sided aluminized polyester film of the sample shows visible physical tears or cracks, record the real-time tensile force value displayed by the testing machine at this time as the initial breaking tension of the surface film material.

[0123] The testing machine continues to run until the sample breaks apart or the suture completely breaks and loses its load-bearing capacity. The maximum load peak during the test is recorded as the overall failure tensile force.

[0124] For Examples 1 to 3, five valid samples were tested respectively. After removing outliers, the arithmetic mean was calculated and recorded in the test table.

[0125] Table 2. Initial breaking tension and overall breaking tensile force test data of the surface film material of the finished products in Examples 1 to 3

[0126] Experimental Groups Total number of insulation layers Initial breaking tension of the surface film (N) Overall breaking tensile force (N) Example 1 30 42.6 185.3 Example 2 50 43.1 296.8 Example 3 70 41.8 412.5

[0127] in conclusion:

[0128] According to the data in Table 2, the insulation blanket samples prepared in Examples 1 to 3, even with a large range in the number of layers, maintained an initial breaking tension of the surface film within a narrow range of 41.8 N to 43.1 N, and the overall breaking tensile strength showed a reasonable positive increasing trend with the increase of the number of stack layers. This reflects that the molding process, while ensuring interlayer fixation, avoids mechanical fatigue or hidden damage to the single-layer substrate.

[0129] The double-sided aluminized polyester film used in the heat-insulating reflective screen is only 6.0μm to 12.0μm thick, and the material itself has a low threshold for puncture resistance and scratch resistance. In traditional manufacturing processes, uneven local stress or hard friction often leaves scratches and micro-lattice fractures on the film surface during material handling, cutting and pressing, causing the finished product to break prematurely due to stress concentration when subjected to external forces.

[0130] Test data from this scheme show that even in Example 3, which processes 70 layers, the tear tension of the outer film material did not deteriorate. This non-destructive processing mechanism stems from the end-to-end surface contact flexibility control, including strictly limiting micro-tension to 0.5–2.0 N / m during layup and using a low-pressure (0.01–0.05 MPa) for covering clamping and translation. The large-area uniformly distributed normal stress replaces localized tangential drag, protecting the structural integrity of the metal coating and the polyester substrate.

[0131] The overall breaking tensile strength data confirms the effectiveness of the linkage between cutting and sewing process parameters. The low-temperature insulation quilt is composed of alternating reflective screens and fiber / knitted mesh spacers, resulting in a low dynamic friction coefficient between the materials. Thick stacks of material are prone to interlayer slippage and misalignment under natural conditions.

[0132] If slippage occurs, the stress cannot be evenly distributed among the layers when the finished product is under tension, leading to a step-like, layer-by-layer fracture. The high overall tensile strength exhibited by the test sample indicates that the stack maintains a high degree of packing density and positional consistency.

[0133] This is attributed to the overall limiting constraint mechanism that intervenes before the positioning and fixing are released during the cutting action, cutting off the physical path of internal stress release causing delamination. At the same time, the sewing station adjusts the presser foot height and sewing tension in real time to address thickness variations caused by different numbers of layers.

[0134] Example 3 uses high tension and large stitch length for thick materials, while Example 1 uses low tension and high speed for thin materials. This ensures that the stitches can penetrate the material stack and form stable shaping and locking nodes, avoiding problems such as the presser foot pushing the material or the thread breaking and falling off the track caused by rigid equipment parameters. Ultimately, it achieves stable output of the mechanical properties of finished products at all levels.

[0135] Test Example 3:

[0136] After completing the alternating laying of 50 layers of substrate in Example 2 and Comparative Example 1, the process was interrupted, the subsequent cutting action was paused, and the material stack was kept in its current original stacking state on the laying platform.

[0137] A 1m×1m square test area was demarcated at the geometric center of the material stack surface as the test reference area.

[0138] A high-resolution industrial vision inspection camera, along with a structured light source, was installed directly above the test area to capture surface images. Surface features were extracted using image recognition software, and the total number of wrinkles, folds, and membrane overlap defects with a length greater than 5mm within the 1m×1m area was counted.

[0139] The test area was non-contactly scanned using a 3D laser profile scanner to obtain 3D point cloud data of the material stack surface. A reference zero-position plane of the test area was fitted in the point cloud processing software, and the maximum positive extreme value in the Z-axis direction relative to the reference plane was extracted and recorded as the local highest protrusion height.

[0140] Clear the current material stack and restart the equipment to execute the material laying procedure. For Example 2 and Comparative Example 1, three independent batches of test samples were produced respectively. The number of defects and the height of protrusions obtained in each batch were arithmetically averaged and recorded.

[0141] Table 3. Material flatness test data of Example 2 and Comparative Example 1

[0142] Experimental Groups Total number of insulation layers Number of wrinkling / folding defects (number / m²) Maximum height of local protrusion (mm) Example 2 50 1.3 0.85 Comparative Example 1 50 27.6 14.32

[0143] in conclusion:

[0144] According to the data in Table 3, the number of wrinkling and folding defects in Example 2 is 1.3 per m. 2 The highest local protrusion height was 0.85 mm, while the corresponding test result for Comparative Example 1 was 27.6 protrusions / m. 2 The two processes, with a thickness of 14.32mm, showed differences in flatness during the laying stage.

[0145] Comparative Example 1 employs a natural stacking pattern without applied micro-tension or edge pre-tightening. The alternating double-sided aluminized polyester film and polyester knitted mesh have low surface density and extremely weak bending stiffness. During the unwinding and release process from the roll to the laying table, residual winding stress within the substrate causes inward curling at the material edges.

[0146] Due to electrostatic adsorption in the physical environment and the air cushion resistance trapped during substrate descent, irregular localized retention and geometric folds occur on the film surface. Without in-plane tension and physical compression along the Z-axis, a single-layer substrate cannot achieve spontaneous flattening. As the number of layers increases to 50, the micro-folds generated in the bottom layer are continuously lifted and amplified through interlayer contact, accumulating stress in the vertical direction. This ultimately forms macroscopic bulges up to 14.32 mm in size and high-density overlapping defects on the surface of the stack, disrupting the parallel structure between layers.

[0147] In Example 2, a tension of 1.2 N / m is applied around the perimeter by mechanical grippers during the transfer of the single-layer substrate. This tension value overcomes the critical stress at which the film material buckles in the plane, counteracts the residual stress of material curling, and resists airflow disturbance, thus maintaining the substrate in a two-dimensional tensile state.

[0148] After the substrate is lowered and aligned, the limiting and clamping mechanism immediately applies a pre-tightening pressure of 0.05 MPa to the edge area to lock it in place. This control logic rigidly solidifies the flattened state of the material. The pre-tightening action compresses the microscopic gaps between adjacent layers, expelling trapped free air and forming a whole with a certain stacking density.

[0149] The laying error of each substrate layer is forcibly corrected and locked in the current layer, blocking the transmission path of stress release and wrinkle deformation to the upper layer. Therefore, after completing 50 layers in Example 2, the highest surface protrusion is pressed to within 1 mm, almost eliminating wrinkling defects and providing a stable and uniform processing foundation for subsequent cutting processes.

[0150] Test Example 4:

[0151] For Example 2 and Comparative Example 2, after the equipment completes the step of cutting the multi-layer stack of materials, the subsequent conveying action is paused, and the obtained cut insulated blank is directly transferred to the horizontal detection reference platform.

[0152] The vertical displacement difference of the cut edge is measured using a digital height ruler with a range of 500mm and a graduation of 0.02mm, in conjunction with a high-precision right-angle backing plate. The bottom edge of the right-angle backing plate is placed against the testing reference platform and pushed flat until it contacts the lowest edge of the bottom surface of the insulation blank. The measuring claws of the digital height ruler are then used to lightly touch the uppermost side edge of the insulation blank from above. The horizontal deviation distance between the uppermost edge and the lowest reference edge is read.

[0153] Along the cutting contour of the insulation blank, select a test point every 300mm in a clockwise direction for measurement, and record the maximum horizontal deviation among all test points as the maximum vertical misalignment between the upper and lower layers.

[0154] A contact surface profilometer was used to perform a linear scan along the normal direction of the cut end face of the insulation blank to detect the length of the torn membrane residue and free fiber bundles extending from the end face. The maximum distance exceeding the normal of the theoretical cut profile surface within the scanned section was recorded as the maximum burr length of the cut surface.

[0155] Five independent batches of adiabatic billet samples were produced for both Example 2 and Comparative Example 2. The measurement actions in steps 2 and 3 were repeated. After removing extreme values ​​caused by external environmental interference, the arithmetic mean was calculated.

[0156] Table 4. Cutting end face quality test data of Example 2 and Comparative Example 2

[0157] Experimental Groups Total number of insulation layers Maximum burr length on the cut surface (mm) Maximum vertical misalignment between upper and lower layers (mm) Example 2 50 0.62 0.41 Comparative Example 2 50 6.87 12.54

[0158] in conclusion:

[0159] According to the data in Table 4, the maximum burr length on the cut surface in Example 2 was controlled at 0.62 mm, and the maximum vertical misalignment between the upper and lower layers was 0.41 mm. In Comparative Example 2, the maximum burr length on the cut surface reached 6.87 mm, and the maximum vertical misalignment between the upper and lower layers surged to 12.54 mm.

[0160] Comparative Example 2 did not apply conformal pre-compression to the periphery during the cutting stage. In a naturally stacked state, multilayer insulation materials exhibit microscopic air layers between layers, demonstrating compressibility under pressure and slippage under shear. When a CNC cutter penetrates the multilayer stack, the lateral compressive stress and cutting friction generated by the cutter edge are greater than the static friction between the material layers.

[0161] Because there is no normal rigid constraint in the Z-axis direction, the material stack is pushed horizontally at the cutting point. The cutting force is released freely to the surroundings, causing the bottom layer of material to be cut while under tension, while the upper layer of material is dragged forward by the blade, resulting in a stepped, sloping misalignment of the cut end face.

[0162] When the membrane material is in a relaxed state without being compressed and taut, the cutting process evolves into local extrusion and physical tearing. The double-sided aluminized polyester film undergoes plastic stretching at the edge of the fracture point, releasing incompletely cut fiber bundles and metal film fragments, forming macroscopic long burrs.

[0163] In Example 2, a closed locking state with a fixed positioning is maintained on the inner side of the cutter's running trajectory using an external clamping mechanism, and a conformal pre-compression of 0.12 MPa is applied to the edge. The intervention of normal pressure eliminates free air between layers, compacts the loose fiber spacers, increases the normal pressure at the interfaces of each material layer, and raises the critical value of the anti-slip static friction force between the multi-layer materials to above the cutting resistance.

[0164] This mechanical constraint creates a high-rigidity mechanical boundary inside the cutting trajectory. The lateral cutting force generated when the cutter penetrates the material stack is completely offset by the rigid constraint wall formed by the outer clamping mechanism, forcing the cutting edge to cut the film and fiber layer, which are in a pressure-locked state, in a single plane.

[0165] The material cannot undergo longitudinal buckling or transverse interlaminar slip, and the cutting tool enables the material to undergo shear fracture by its own mechanism. The stack maintains a consistent physical morphology before and after cutting, and the cut surface remains vertical and neat on a macroscopic scale, with end face burrs limited to a low industrial tolerance range.

[0166] Test Example 5:

[0167] For Example 2 and Comparative Example 3, after the cutting of the multi-layer stack of materials is completed and the tool is reset, when the system is in a static waiting state, a laser marking instrument is used to vertically irradiate a linear laser reference line with a width of 0.1mm on the cutting end face of the insulating blank on one side. At this time, an industrial camera is used to capture the first frame image perpendicular to the end face as the initial reference zero position.

[0168] Start the conveying program of the equipment. Comparative Example 3 follows the sequence of releasing the outer clamping before clamping and conveying; Example 2 follows the sequence of pre-clamping before releasing the outer clamping. Both sets of insulating blanks are conveyed horizontally to the sewing station while being clamped.

[0169] When the insulating blank reaches the sewing station and stops moving, before the sewing machine head inserts the needle, maintain the current clamping state and use the same industrial camera to capture a second frame image at the same distance perpendicular to the end face.

[0170] Import the second frame image into the contour comparison software. Due to the relative slippage of the internal layers, the end faces of the substrate layers that were originally on the same vertical plane in the first frame will be misaligned and deformed. Establish a coordinate system with the end face position of the bottom substrate layer as the reference origin, measure the horizontal distance of the end face of each internal substrate layer from the vertical reference axis, and record the horizontal displacement that is farthest from the origin as the maximum relative slippage between the internal layers.

[0171] For the production batches of Example 2 and Comparative Example 3, the above test process was repeated to extract 5 sets of sample data. The maximum relative slip obtained in a single test was arithmetically averaged and recorded.

[0172] Table 5. Test data of maximum relative slippage between translational transport layers in Example 2 and Comparative Example 3.

[0173] Experimental Groups Total number of insulation layers Maximum relative slip between internal layers (mm) Example 2 50 0.29 Comparative Example 3 50 11.46

[0174] in conclusion:

[0175] According to the data in Table 5, the maximum relative slippage between the internal layers in Example 2 was 0.29 mm, while the maximum relative slippage between the internal layers in Comparative Example 3 reached 11.46 mm. The change in the timing of the actions directly caused variations in the stability of the interlayer structure during the translational transport process.

[0176] During the laying and cutting processes, the insulation substrate is continuously subjected to pre-tightening pressure in the Z-axis direction. The loose cryogenic insulation spacers inside are compressed, and a large amount of elastic compressive potential energy is stored inside the material stack. Comparative Example 3 adopts the conventional logic of first releasing the positioning fixation and then clamping and conveying. At the moment the outer clamping mechanism is released, the mechanical boundary disappears, the elastic compressive potential energy inside the material stack is released, and each layer of substrate rebounds and expands in the Z-axis direction.

[0177] Springback reduces the interlayer contact area and lowers the normal pressure, macroscopically manifesting as a looser material and a drop in interlayer static friction to a critical lower limit. When the conveying mechanism intervenes to clamp and perform translational conveying, the system undergoes a dynamic process of acceleration and deceleration, with the translational inertial force exceeding the interlayer static friction in the springback state. The intermediate layer, not directly controlled by the external clamping plate, undergoes physical displacement due to inertial lag or lead over the outer surface layer, ultimately resulting in a stepped, loosely layered misalignment at the cut end face.

[0178] Example 2 employs a constraint relay timing sequence. Before the fixed positioning is released, the conveying mechanism pre-applies a 0.03MPa covering clamp to the upper and lower surfaces of the cut insulated billet. At this junction, the system is in an overlapping state where two sets of physical constraints coexist. Since the new Z-axis limiting boundary has been established before the old boundary is removed, the compressive potential energy inside the stack is continuously confined, and there is no space for the material to rebound along the Z-axis. High positive pressure and stable static friction are maintained between layers.

[0179] The system then translates at a speed of 0.4 m / s while maintaining the covering clamp. The large-area covering clamp ensures the uniformity of normal stress transmission, and the frictional resistance between the internal layers is much greater than the inertial shear force generated by the system translation. This seamless switching of mechanical boundaries blocks the path of internal stress release, and the insulated billet is transferred between workstations as a physical unit with overall rigidity, achieving zero displacement maintenance of the hierarchical structure.

[0180] Test Example 6:

[0181] For Example 3 and Comparative Example 4, a production task was set up to continuously process 10 finished 70-layer thermal insulation quilts. Both sets of experiments used the same batch of sewing thread and bobbin thread, and the sewing machine head was cleaned and the mechanical transmission components were ensured to be in standard lubrication condition.

[0182] In Example 3, when the insulated blank is input into the sewing station, the system acquires thickness information and performs adaptive adjustment. The height of the presser foot from the needle plate is adjusted to 15.0 mm, and the tension of the top and bottom threads is adjusted to 4.0 N. In Comparative Example 4, the thickness information feedback loop is cut off, and preset thin material fixed parameters are forcibly adopted. The height of the presser foot from the needle plate is fixed at 3.0 mm, and the tension of the top and bottom threads is fixed at 1.0 N.

[0183] Start the equipment and, while maintaining overall limit constraints, control the sewing machine head to perform edge locking and reinforcement sewing along the outer perimeter of the insulation blank, and perform array dot stitching in the middle area.

[0184] During production, the equipment's built-in breakage sensor records the cumulative number of breaks in the top and bottom threads. After each breakage, the threads are manually re-threaded and operation is resumed, with the interruption event recorded.

[0185] After the production batch is completed, 10 finished products are laid flat on the inspection table. A high-precision stitch inspection vision system is used to scan and count the total number of stitches and the number of skipped stitches that do not form stitches within the full coverage area. The skipped stitch rate is calculated as the percentage of skipped stitches out of the total number of stitches.

[0186] Using a surface defect detection light source in conjunction with manual visual inspection, check the surface of the finished product for localized tears, holes, and physical deformation of the aluminized polyester film caused by pressure foot dragging or forced pushing. The total number of defects in 10 finished products is taken as the number of localized tear defects of the film material.

[0187] Table 6. Test data on sewing defects of extra-thick materials in Example 3 and Comparative Example 4

[0188] Experimental Groups Total number of insulation layers Total number of disconnections (times) Skipped stitch rate (%) Number of localized tear defects in the membrane material (individual) Example 3 70 2 0.14 1 Comparative Example 4 70 37 8.62 43

[0189] in conclusion:

[0190] According to the data in Table 6, in Comparative Example 4, when continuously processing 70 layers of thick material, the cumulative number of thread breaks reached 37, the skipped needle rate was 8.62%, and the number of local tear defects in the membrane material was as high as 43, making it impossible for the equipment to maintain normal industrial production. In Example 3, the number of thread breaks was only 2, the skipped needle rate was controlled at 0.14%, and the number of local tear defects in the membrane material was only 1, demonstrating significant process stability.

[0191] Comparative Example 4 uses a fixed presser foot height of 3.0mm to process a 70-layer stack of material. The actual physical thickness of the 70-layer substrate is far greater than 3.0mm. The presser foot is forcibly pressed down before the needle goes down, generating a large local static compressive force on the material. During the sewing machine's feed dog action, the bottom surface of the presser foot generates high-intensity sliding friction resistance with the surface of the material.

[0192] The low tensile strength of the surface reflector substrate leads to tangential yielding under strong pressure and pulling, causing irreversible physical tearing of the film material. A fixed wire tension of 1.0N fails to match the frictional characteristics of the thick material. When the needle penetrates 70 layers of material, it experiences enormous normal frictional force, stretching the wire. Due to the low base tension, the surface thread cannot overcome the internal friction of the material to successfully retract and form a full loop during needle return. The shuttle tip misses the loop, causing the surface thread to fail to interweave, resulting in high-frequency needle skipping. Simultaneously, the loose surface thread clogged between the needle hole and the material surface is easily broken by repeated punctures from the needle, leading to a surge in thread breakage.

[0193] Example 3 utilizes thickness information feedforward to increase the presser foot height to 15.0 mm. The increased presser foot stroke accommodates the volume of a 70-layer stack, and the presser foot bottom provides moderate normal conformal pressure without causing destructive rigid compression. Under this pressure, the fabric feeding mechanism achieves synchronous feeding of the top and bottom layers, avoiding interlayer displacement and eliminating shear tearing sources on the film surface. The tension of the top and bottom threads is simultaneously increased to 4.0 N.

[0194] The high-tension preload compensates for tension loss when the thread penetrates multiple layers of fibers and films. As the needle reaches bottom dead center and rises, a 4.0N tension forces the thread to overcome material resistance, tighten instantly, and expand outwards, forming a stable, precisely sized and positioned loop below the needle plate. The rotary hook accurately hooks the loop, achieving phase-locked weaving and eliminating the physical preconditions for skipped stitches. Adaptive parameter matching ensures a force balance between the mechanical sewing action and the material's physical properties, maintaining stitch formation rate and substrate integrity even under extreme thick-layer conditions.

Claims

1. A process for integrally laying and cutting seams of a special insulation blanket for the jacket of a low-temperature vacuum container, comprising the following steps: Tension is applied to a single-layer substrate to flatten it and lay it out. After each layer of the single-layer substrate is laid, a constraint force is applied to the laid substrate to position and fix it. Repeat the above actions of flattening, laying, and fixing until the set total number of layers is reached, forming a multi-layer stack of materials. While maintaining the multi-layer stack in the fixed position, the multi-layer stack is cut and the waste material is separated to obtain the cut insulated blank. An overall limiting constraint is applied to the cut insulation blank, and the cut insulation blank is translated and transported to the sewing station while maintaining the overall limiting constraint, keeping the relative stacking position between the layers inside the cut insulation blank unchanged throughout the process. The thickness information of the cut insulation blank is obtained, and the sewing parameters are adaptively adjusted according to the thickness information before sewing and shaping, and the finished insulation quilt is output.

2. The process according to claim 1, characterized in that, The laying and positioning steps further include: The single-layer substrate is gripped by a mechanical gripper module, and the single-layer substrate is flattened by applying uniform tension to all sides through a servo drive unit. Move the flattened single-layer substrate directly above the spreading platform and lower it for alignment; The positioning and fixing are completed by applying pressure to the edge area of ​​the laid substrate in the Z-axis direction using a limiting and clamping mechanism, and the total number of layers is set to be 30 to 70.

3. The process according to claim 1, characterized in that, The step of cutting a multi-layered stack of materials further includes: An external clamping mechanism is used to maintain the multi-layer stack in the fixed positioning state. A CNC cutting system operates within the fixed position of the multi-layer material stack according to a preset two-dimensional contour trajectory, and the cutter penetrates the multi-layer material stack in one go.

4. The process according to claim 1, characterized in that, The steps of applying overall limiting constraints and translational transport further include the following action sequence: Before the fixed position is released, the conveying mechanism performs a covering clamping on both the upper and lower sides of the cut insulated blank.

5. The process according to claim 1, characterized in that, The adaptive adjustment and suture shaping steps further include: The sewing parameters include the height of the presser foot from the needle plate and the tension of the sewing top thread and bottom thread; The suture shaping includes: Continuous overlock stitching is performed along the outer edge of the cut insulation blank; and array dot stitching is performed on the middle surface area of ​​the cut insulation blank.

6. The process according to claim 2, characterized in that, The tension is in the range of 0.5 to 2.0 N / m; The translational speed for moving the single-layer substrate to the top of the spreading platform is 0.5 to 1.5 m / s, and the descent speed for lowering and aligning the single-layer substrate is 0.1 to 0.3 m / s. The pressure is in the range of 0.02 to 0.08 MPa.

7. The process according to claim 3, characterized in that: The pressure applied by the peripheral clamping mechanism while maintaining the fixed positioning is in the range of 0.10 to 0.15 MPa. The feed rate of the CNC cutting system is in the range of 1.5 to 4.0 m / min.

8. The process according to claim 4, characterized in that: The relative clamping pressure of the covered clamp is in the range of 0.01 to 0.05 MPa; The conveying mechanism moves the cut insulating blank to the sewing station at a speed of 0.2 to 0.6 m / s.

9. The process according to claim 5, characterized in that: The height of the presser foot from the needle plate is 3.0 to 15.0 mm, and the tension between the sewing thread and the bobbin thread is 1.0 to 4.0 N; The continuous overlock reinforcement sewing has a rotation speed of 800-1200 rpm and a stitch length of 3.0-5.0 mm. The rotation speed of the array dot stitch is 500-800 rpm, the dot spacing is 150-300 mm, and the needle spacing is 6.0-10.0 mm.

10. The process according to claim 1, characterized in that: The single-layer substrate consists of alternating cryogenic thermal insulation reflective screens and cryogenic thermal insulation spacers; The cryogenic thermal insulation reflective screen is a double-sided aluminized polyester film with a thickness in the range of 6.0 to 12.0 μm; The cryogenic insulation spacer is made of alkali-free glass microfiber paper or polyester knitted mesh with a surface density in the range of 15 to 35 g / m².

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