One-way weaving method and equipment for composite S-shaped air inlet duct cylinder

Abstract

The invention discloses a one-way weaving method and equipment for a composite material S-shaped air inlet channel cylinder, and relates to the technical field of composite material weaving. A one-way weaving method for a composite S-shaped air inlet duct cylinder comprises the following steps that a weaving core mold is designed according to the geometric shape of the S-shaped air inlet duct cylinder, and a moving track generatrix of the weaving core mold is designed; according to the layer laying angle design requirement of the S-shaped air inlet channel cylinder, the robot motion control system drives the weaving core mold to do reciprocating motion along the moving track generatrix, the process parameters of the two-dimensional weaving machine and the single yarn winding machine are controlled, the surface of the weaving core mold is coated with a one-way weaving layer and a 90-degree yarn layer, and a weaving prefabricated body is obtained; and carrying out vacuum infusion, resin curing and demolding treatment on the woven prefabricated body to obtain the finished product S-shaped air inlet channel cylinder. The surface of the weaving core mold is coated with the one-way weaving layer and the 90-degree yarn layer, so that the in-plane mechanical property of the S-shaped air inlet channel cylinder can be improved, the annular pressure bearing capacity of the S-shaped air inlet channel cylinder is enhanced, and light weight is achieved.

Description

Technical Field

[0001] This application relates to the field of composite material weaving technology, and in particular to a unidirectional weaving method and equipment for a composite material S-shaped air intake cylinder. Background Technology

[0002] As a key component of aerospace engines, the S-shaped air intake duct must meet the requirements of high specific strength, lightweight, and complex aerodynamic shape. Existing manufacturing processes mainly involve manual prepreg lay-up and two-dimensional weaving. However, manual prepreg lay-up is not only inefficient but also results in fiber discontinuity due to cutting, leading to poor mechanical properties in the resulting air intake duct. While two-dimensional weaving can achieve near-net-shape forming using continuous fibers and improve production efficiency, the fibers undergo buckling deformation in the thickness direction at the interlacing points, negatively impacting the in-plane mechanical properties of the part. Furthermore, fiber buckling increases the areal density of the fabric, thus increasing the mass of the air intake duct. Traditional two-dimensional weaving structures are limited by the self-locking mechanism of the braided yarn, restricting the weaving angle to between 15° and 70°, preventing a 90° circumferential wrapping of the air intake duct mold. This results in weak circumferential pressure resistance, requiring an increase in the number of lay-up layers to improve pressure resistance, further increasing the weight of the air intake duct. Therefore, there is an urgent need for a manufacturing method for S-shaped air intake cylinders that combines high performance, lightweight design, and automated molding. Summary of the Invention

[0003] The main objective of this application is to provide a unidirectional weaving method and equipment for a composite material S-shaped air intake cylinder, which aims to solve the technical problem that the S-shaped air intake cylinder prepared by existing methods cannot simultaneously achieve mechanical performance and lightweight design.

[0004] To achieve the above objectives, this application proposes a unidirectional weaving method for a composite material S-shaped air intake cylinder, comprising the following steps: The braided core mold is designed based on the geometric shape of the S-shaped air intake cylinder, and the running trajectory generatrix of the braided core mold is designed. According to the layup angle design requirements of the S-shaped air intake cylinder, the robot motion control system drives the braided core mold to reciprocate along the running trajectory generatrix, and controls the process parameters of the two-dimensional braiding machine and the single yarn winding machine to cover the surface of the braided core mold with a unidirectional braided layer and a 90° yarn layer respectively, to obtain a braided preform. After vacuum injection, resin curing and demolding of the woven preform, the finished S-shaped air intake cylinder is obtained.

[0005] Optionally, in the step of designing the running trajectory generatrix of the braided core mold, the running trajectory generatrix of the braided core mold is extracted using CATIA software, and the braiding point and the single yarn winding point are located on the running trajectory generatrix. Wherein, the weaving point is the position on the surface of the weaving core mold after the yarns interweave to form a fabric in the two-dimensional weaving machine, and the single yarn winding point is the position on the surface of the weaving core mold where the yarns of the single yarn winding machine are deposited.

[0006] Optionally, the step of driving the braided core mold to reciprocate along the running trajectory generatrix via the robot motion control system includes: Extract the discrete point coordinates of the running trajectory generatrix and import them into the robot motion control system; The robot motion control system drives the braiding core mold to reciprocate along the running trajectory generatrix. When the braiding core mold runs along the running trajectory generatrix, the line connecting the center of the cross-section of the braiding core mold at the braiding point and the center of the track disk of the two-dimensional braiding machine is the normal line of the track disk plane of the two-dimensional braiding machine. When the braiding mandrel runs along the running trajectory generatrix, the center of the cross-section of the braiding mandrel at the single yarn winding point coincides with the center of the track disk of the single yarn winding machine.

[0007] Optionally, the step of controlling the process parameters of the two-dimensional braiding machine and the single yarn winding machine, respectively covering the surface of the braiding mandrel with a unidirectional braiding layer and a 90° yarn layer, includes: According to the design requirements of the braiding angle, the rotation speed of the two-dimensional braiding machine and the movement speed of the braiding mandrel are adjusted, and a unidirectional braiding layer is wrapped on the surface of the braiding mandrel by the two-dimensional braiding machine; Adjust the rotation speed of the single yarn winding machine to control the yarn of the single yarn winding machine to wind perpendicular to the axis of the braiding mandrel, forming a 90° yarn layer on the surface of the braiding mandrel.

[0008] Optionally, the unidirectional braided layer includes a first unidirectional braided layer and a second unidirectional braided layer; When the braiding core mold moves forward along the running trajectory generatrix, the first unidirectional braiding layer is covered on the surface of the braiding core mold. The load-bearing yarn of the first unidirectional braiding layer includes a 0° yarn parallel to the axis of the braiding core mold and a slanted yarn at an angle of +θ° to the axis of the braiding core mold. When the braiding core mold retracts along the running trajectory generatrix, the second unidirectional braiding layer is covered on the surface of the braiding core mold. The load-bearing yarns of the second unidirectional braiding layer include 0° yarns parallel to the axis of the braiding core mold and oblique yarns at an angle of -θ° to the axis of the braiding core mold. Wherein, the forward speed and backward speed of the braided core mold are the same, and θ is the braiding angle.

[0009] Optionally, the yarns of the unidirectional braided layer include reinforcing yarns, axial yarns, and auxiliary yarns; The cross-sectional area of ​​the auxiliary yarn is less than 1 / 30 of the cross-sectional area of ​​the reinforcing yarn; The ratio of the reinforcing yarn to the auxiliary yarn is (1-3):1; The ratio of the reinforcing yarn to the axial yarn is one of 1:1, 2:1, 4:1 or 8:1.

[0010] Optionally, the reinforcing yarn and the axial yarn are the same type of carbon fiber yarn, and the auxiliary yarn is nylon yarn.

[0011] Optionally, the step of obtaining the finished S-shaped air intake cylinder after vacuum injection, resin curing, and demolding of the woven preform includes: After cutting and cleaning both ends of the woven preform, a peelable fabric and a flow guide net are laid on the outer periphery. An injection port is set at the bottom of the woven preform, and an outlet port is set at the top of the woven preform. After wrapping it with a sealed bag, a vacuum is drawn. When the vacuum degree is not lower than -0.095MPa within 25min-30min, glue is injected through the injection port until resin flows out of the outlet and the flowing resin is free of bubbles for 10min-15min, then the glue injection is completed. After the woven preform is cured by injection and cooled to room temperature, it is demolded to obtain the finished S-shaped air intake cylinder.

[0012] This application also proposes a one-way weaving device for a composite material S-shaped air intake cylinder, used to implement the above-mentioned one-way weaving method for the composite material S-shaped air intake cylinder, the one-way weaving device comprising: A two-dimensional braiding machine, wherein a unidirectional braiding layer is coated on the surface of the braiding core mold; A single yarn winding machine is located in front of the two-dimensional braiding machine. The single yarn winding machine winds a 90° yarn layer perpendicular to the axis of the braiding mandrel on the surface of the braiding mandrel. A robot motion control system is connected to the two-dimensional knitting machine, the single yarn winding machine, and the knitting mandrel. The robot motion control system can adjust the process parameters of the two-dimensional knitting machine and the single yarn winding machine, and control the knitting mandrel to reciprocate along the running trajectory generatrix.

[0013] Optionally, the robot motion control system includes a KUKA 6-axis robot, the end of which is connected to the knitting mandrel to drive the knitting mandrel to reciprocate along the running trajectory generatrix.

[0014] The beneficial effects of this application include: This application prepares an S-shaped air intake cylinder based on a unidirectional braiding process. Since the two sets of reinforcing yarns in the traditional two-dimensional triaxial braiding process are usually made of high-performance fibers such as carbon fiber and aramid, this will cause the reinforcing yarns to buckle and deform in the thickness direction at the interlacing point. Therefore, based on the traditional two-dimensional triaxial braiding process, this application replaces the two sets of reinforcing yarns in the two-dimensional braiding machine with one set of reinforcing yarns and one set of auxiliary yarns with a smaller cross-sectional area. The auxiliary yarns can help position the reinforcing yarns at the locations where the cross-section of the braiding mandrel changes abruptly, and can also effectively reduce the degree of buckling and deformation of the reinforcing yarns in the thickness direction in the braided fabric, thereby improving the in-plane mechanical properties of the S-shaped air intake cylinder. This application involves wrapping a unidirectional braided layer around the surface of the braided core mold, and then using a single yarn winding machine to wrap another continuous 90° yarn layer around the surface of the braided core mold to achieve a 90° circumferential wrapping of the braided core mold. This overcomes the limitation of the traditional two-dimensional braided structure, which is restricted by the self-locking mechanism of the braided yarn and the braiding angle can only vary between 15° and 70°. The independent winding of the 90° yarn layer eliminates the weakness of the interlaced structure and enhances the circumferential pressure bearing capacity of the S-shaped air intake cylinder. This application reduces the areal density of the two-dimensional woven fabric by reducing the degree of yarn crimp, thereby reducing the mass of the S-shaped air intake cylinder. Furthermore, the winding of the 90° yarn layer enhances the circumferential pressure bearing capacity of the S-shaped air intake cylinder, eliminating the need to increase the number of lay-up layers to improve its pressure bearing capacity. This reduces redundant lay-up layers, resulting in a reduction in the total thickness of the lay-up layers and further achieving the lightweighting of the S-shaped air intake cylinder. This application utilizes a robot motion control system for automated weaving, enabling continuous fiber weaving without the need for fiber cutting and manual stacking, thus effectively reducing production costs and improving production efficiency. Attached Figure Description

[0015] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on the structures shown in these drawings without creative effort.

[0016] Figure 1 This is a schematic diagram of the weaving process of the unidirectional weaving device described in the embodiments of this application; Figure 2 This is a schematic diagram of the track plate of the single yarn winding machine described in the embodiments of this application; Figure 3 This is a schematic diagram of the layup structure of the first unidirectional braided layer described in an embodiment of this application; Figure 4This is a schematic diagram of the layup structure of the second unidirectional braided layer described in an embodiment of this application; Figure 5 This is a schematic diagram of the 90° yarn layer layup structure described in the embodiments of this application; Figure 6 This is a schematic diagram of the vacuum-assisted forming of the S-shaped air intake cylinder described in the embodiments of this application.

[0017] Figure label: 1-Woven core mold; 2-Two-dimensional braiding machine; 3-Single yarn winding machine; 4-Robot motion control system; 5-90° yarn; 6-Reinforcing yarn; 7-Auxiliary yarn; 8-Board yarn; 9-Woven preform; 10-Peelable fabric; 11-Flow guide net; 12-Glue inlet; 13-Glue outlet; 14-Sealed bag.

[0018] The realization of the purpose, functional features and advantages of this application will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0019] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of the embodiments. Based on the embodiments of this application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of this application.

[0020] To address the technical problems existing in the prior art, embodiments of this application provide a unidirectional weaving method for a composite material S-shaped air intake cylinder, comprising the following steps: S1. Design the braided core mold 1 according to the geometric shape of the S-shaped air intake cylinder, and design the running trajectory generatrix of the braided core mold 1.

[0021] In the specific implementation process, the running trajectory generatrix of the braiding core mold 1 is extracted by CATIA software, and the braiding point and the single yarn winding point are located on the running trajectory generatrix. Wherein, the weaving point is the position on the surface of the weaving core mold 1 after the yarns interweave to form a fabric in the two-dimensional weaving machine 2, and the single yarn winding point is the position on the surface of the weaving core mold 1 where the yarns of the single yarn winding machine 3 are deposited.

[0022] When designing the running trajectory busbar of braided mandrel 1 using CATIA software, it is necessary to ensure that: When the braiding core mold 1 runs along the running trajectory generatrix, the line connecting the center of the cross section of the braiding core mold 1 at the braiding point and the center of the track disk of the two-dimensional braiding machine 2 is the normal line of the track disk plane of the two-dimensional braiding machine 2. When the braiding core mold 1 runs along the running trajectory generatrix, since the yarns in the single yarn winding machine 3 do not interweave, the yarn deposition point is located in the plane of the track disk. At this time, it should be ensured that the center of the cross section of the braiding core mold 1 at the single yarn winding point coincides with the center of the track disk of the single yarn winding machine 3.

[0023] S2. According to the design requirements of the layup angle of the S-shaped air intake cylinder, the discrete point coordinates of the running trajectory generatrix are extracted and imported into the robot motion control system 4. The robot motion control system 4 drives the braided core mold 1 to reciprocate along the running trajectory generatrix, and controls the process parameters of the two-dimensional braiding machine 2 and the single yarn winding machine 3 to cover the surface of the braided core mold 1 with a unidirectional braided layer and a 90° yarn layer respectively, to obtain the braided preform 9.

[0024] In the specific implementation process, according to the design requirements of the braiding angle, the rotation speed of the two-dimensional braiding machine 2 and the movement speed of the braiding core mold 1 are adjusted, and a unidirectional braiding layer is wrapped on the surface of the braiding core mold 1 by the two-dimensional braiding machine 2.

[0025] Specifically, the unidirectional braided layer includes a first unidirectional braided layer and a second unidirectional braided layer; the yarns of the unidirectional braided layer include reinforcing yarn 6, axial yarn 8, and auxiliary yarn 7.

[0026] When the braiding core mold 1 moves along the running trajectory generatrix, the first unidirectional braiding layer is covered on the surface of the braiding core mold 1. Since the unidirectional braiding process used in this application only has the shaft yarn 8 and a set of reinforcing yarns 6, and the auxiliary yarn 7 only plays the role of helping the reinforcing yarn 6 to be positioned, the load-bearing yarns of the first unidirectional braiding layer include 0° yarns parallel to the axis of the braiding core mold 1 and oblique yarns at an angle of +θ° with the axis of the braiding core mold 1. When the braiding core mold 1 retracts along the running trajectory generatrix, the second unidirectional braiding layer is covered on the surface of the braiding core mold 1. The load-bearing yarns of the second unidirectional braiding layer include 0° yarns parallel to the axis of the braiding core mold 1 and oblique yarns at an angle of -θ° to the axis of the braiding core mold 1. Wherein, the forward speed and backward speed of the braided core mold 1 are the same, and θ is the braiding angle.

[0027] Specifically, in order to effectively reduce the buckling deformation of the reinforcing yarn 6, the cross-sectional area of ​​the auxiliary yarn 7 should be less than 1 / 30 of the cross-sectional area of ​​the reinforcing yarn 6. This auxiliary yarn 7 does not contribute to the mechanical properties of the material, but only plays a role in helping to position the reinforcing yarn 6; the ratio of the number of reinforcing yarn 6 to the number of auxiliary yarn 7 is (1-3):1; the ratio of the number of reinforcing yarn 6 to the number of axial yarn 8 is one of 1:1, 2:1, 4:1 or 8:1; the reinforcing yarn 6 and the axial yarn 8 are carbon fiber yarns of the same type, and the auxiliary yarn 7 is nylon yarn.

[0028] In the specific implementation process, after the unidirectional braided layer is covered on the surface of the braided core mold 1, the braided core mold 1 is run through the single yarn winding machine 3 according to the layup design requirements. The rotation speed of the single yarn winding machine 3 is adjusted to control the yarn of the single yarn winding machine 3 to be wound perpendicular to the axis of the braided core mold 1, thereby forming a 90° yarn layer on the surface of the braided core mold 1. The independent winding of the 90° yarn layer can eliminate the weakness of the interlaced structure and enhance the circumferential pressure bearing capacity of the S-shaped air intake cylinder, replacing the need for thicker layup, thus reducing the total layup thickness and achieving the lightweighting of the S-shaped air intake cylinder.

[0029] Specifically, the yarn used in the single yarn winding machine 3 is carbon fiber yarn.

[0030] S3. After vacuum injection, resin curing and demolding of the woven preform 9, the finished S-shaped air intake cylinder is obtained.

[0031] In the specific implementation process, after cutting and cleaning both ends of the woven prefabricated body 9, a peelable fabric 10 and a guide net 11 are laid on the outer periphery, and an injection port 12 is set below the woven prefabricated body 9, and an outlet port 13 is set above the woven prefabricated body 9. After wrapping with a sealing bag 14, a vacuum is drawn. When the vacuum degree is not lower than -0.095MPa within 25min-30min, glue is injected through the glue injection port 12 until resin flows out of the glue outlet 13, and the flowing resin is free of bubbles for 10min-15min, then the glue injection is completed. After the woven preform 9 is cured after being injected with glue, it is cooled to room temperature and then demolded to obtain the finished S-shaped air intake cylinder.

[0032] Embodiments of this application also provide a unidirectional weaving device for a composite material S-shaped air intake cylinder, such as... Figure 1 As shown, a unidirectional weaving method for implementing the above-mentioned composite material S-shaped air intake cylinder is provided, wherein the unidirectional weaving equipment includes: Two-dimensional braiding machine 2, wherein the two-dimensional braiding machine 2 covers the surface of the braiding core mold 1 with a unidirectional braiding layer; A single yarn winding machine 3 is located in front of the two-dimensional braiding machine 2. The single yarn winding machine 3 winds a 90° yarn layer perpendicular to the axis of the braiding mandrel 1 onto the surface of the mandrel 1. Figure 2 As shown; The robot motion control system 4 is connected to the two-dimensional braiding machine 2, the single yarn winding machine 3 and the braiding mandrel 1 respectively. The robot motion control system 4 can adjust the process parameters of the two-dimensional braiding machine 2 and the single yarn winding machine 3, and control the braiding mandrel 1 to reciprocate along the running trajectory generatrix.

[0033] The unidirectional weaving equipment of this application includes a two-dimensional weaving machine 2, a single yarn winding machine 3, and a robot motion control system 4. The robot motion control system 4 can adjust the rotation speed of the two-dimensional weaving machine 2 and the single yarn winding machine 3, and adjust the forward and backward speeds of the weaving mandrel 1. The robot motion control system 4 controls the weaving mandrel 1 to reciprocate along the generatrix of the running trajectory, and adjusts the movement speed of the weaving mandrel 1 and the rotation speed of the two-dimensional weaving machine 2 according to the set weaving angle to ensure that the weaving angle meets the set requirements. At the same time, it adjusts the rotation speed of the single yarn winding machine 3 so that the yarn of the single yarn winding machine 3 can be wound perpendicular to the surface of the weaving mandrel 1. Through this unidirectional weaving equipment, the automated weaving of the prefabricated body 9 can be realized. The unidirectional weaving equipment of this application not only improves the quality of the prepared S-shaped air intake cylinder product, but also reduces production costs and improves production efficiency.

[0034] As one possible implementation of this application, the robot motion control system 4 includes a KUKA 6-axis robot, the end of which is connected to the knitting core 1 to drive the knitting core 1 to reciprocate along the running trajectory generatrix.

[0035] The technical solutions described above in this application will be explained in detail below with reference to specific embodiments.

[0036] Example 1 A unidirectional weaving method for a composite material S-shaped air intake cylinder includes the following steps: Step 1: Design of Braided Core Mold 1 and Planning of Running Trajectory Busbar Design the woven core mold 1 based on the geometric shape of the S-shaped air intake cylinder; The running trajectory generatrix of the braiding mandrel 1 is extracted using CATIA software. The braiding point (the position where the yarn is deposited on the surface of the braiding mandrel 1 after interlacing to form a fabric in the 2D braiding machine 2) and the single yarn winding point (the position where the yarn of the single yarn winding machine 3 is deposited on the surface of the braiding mandrel 1) are located on the running trajectory generatrix. When planning the running trajectory generatrix, it is necessary to ensure that: when the braiding mandrel 1 runs along the running trajectory generatrix, the line connecting the center of the cross section of the braiding mandrel 1 at the braiding point and the center of the track disk of the 2D braiding machine 2 is perpendicular to the track disk plane of the 2D braiding machine 2; when the braiding mandrel 1 runs along the running trajectory generatrix, the center of the cross section of the braiding mandrel 1 at the single yarn winding point coincides with the center of the track disk of the single yarn winding machine 3.

[0037] Step 2: Execution of the layup process Extract the discrete point coordinates of the running trajectory generatrix and import them into the robot motion control system 4, setting the discrete point coordinate density to 80 points / meter; With the weaving angle set to θ = 45°, the robot motion control system 4 drives the weaving core mold 1 to reciprocate along the running trajectory generatrix, weaving in the following sequence: Step 1) The braiding mandrel 1 advances along the running trajectory generatrix, and a first unidirectional braiding layer is wrapped on the surface of the braiding mandrel 1 by the two-dimensional braiding machine 2. The angle of the load-bearing yarn in the first unidirectional braiding layer is 0° (parallel to the axis of the braiding mandrel 1) and +45° (forming an angle of +45° with the axis of the braiding mandrel 1), such as... Figure 3 As shown; Step 2) The braiding mandrel 1 retracts along the running trajectory generatrix, and a second unidirectional braiding layer is wrapped on the surface of the braiding mandrel 1 by the two-dimensional braiding machine 2. The angles of the load-bearing yarns in the second unidirectional braiding layer are 0° and -45°, as shown. Figure 4 As shown; Step 3) The braided core mold 1 is wound with 90° yarn 5 using a single yarn winding machine 3 to form a 90° yarn layer, such as... Figure 5 As shown; Step 4) Repeat the operation in Step 1); Step 5) Repeat step 2); Step 6) Repeat step 2); Step 7) Repeat step 1); Step 8) Repeat step 3); Step 9) Repeat step 2); Step 10) Repeat the operation in Step 1); The final ply angle is: The woven prefabricated body 9 is [0° / +45° / -45° / 0° / 90° / 0° / +45° / -45° / 0° / -45° / 0° / 0° / +45° / 90° / -45° / 0° / 0° / +45°], where " / " indicates the separation of different layups.

[0038] The yarn specifications used in this embodiment are shown in Table 1 below.

[0039] Table 1

[0040] Step 3, processing of the woven prefabricated body 9 like Figure 6 As shown, after cutting and cleaning both ends of the woven preform 9, a peelable fabric 10 and a flow guide net 11 are laid on the outer periphery. When laying the flow guide net 11, it should be noted that both ends of the flow guide net 11 should be 10cm shorter than both ends of the woven preform 9 so that the resin impregnation is more uniform. Then, glue injection ports 12 are set on both sides of the lower part of the woven preform 9, and glue outlet 13 is set in the middle of the upper part of the woven preform 9. After wrapping with a sealing bag 14, a vacuum is drawn. If the vacuum degree of the sealed bag 14 is not lower than -0.095MPa within 25min-30min, then the airtightness is qualified.

[0041] Step 4: Resin Injection and Curing like Figure 6 As shown, under an injection pressure of 0.095 MPa, the sealing bag 14 is injected with glue through the injection port 12. When the resin flows out of the outlet 13 and there are no bubbles in the flowing resin for 10-15 minutes, the injection is completed. After closing the glue injection port 12 and the glue outlet 13, the woven preform 9 after glue injection is cured, cooled to room temperature, and demolded to obtain the finished S-shaped air inlet cylinder.

[0042] In summary, this application fabricates an S-shaped air intake cylinder based on a unidirectional braiding process. Since traditional two-dimensional triaxial braiding processes typically use high-performance fibers such as carbon fiber and aramid for the two sets of reinforcing yarns, this can lead to buckling deformation in the thickness direction at the interlacing points. Therefore, this application, based on the traditional two-dimensional triaxial braiding process, replaces the two sets of reinforcing yarns in the two-dimensional braiding machine with one set of reinforcing yarn and one set of auxiliary yarn with a smaller cross-sectional area. The auxiliary yarn helps to position the reinforcing yarn at locations where the cross-section of the braiding mandrel changes abruptly, and also effectively reduces the degree of buckling deformation of the reinforcing yarn in the thickness direction of the woven fabric, thereby improving the in-plane mechanical properties of the S-shaped air intake cylinder. After wrapping the surface of the braiding mandrel with a unidirectional braided layer, this application uses a single-yarn winding machine to wind another continuous 90° yarn layer onto the surface of the braiding mandrel, thus achieving a 90° circumferential wrapping of the braiding mandrel, overcoming the limitations of traditional two-dimensional braiding structures caused by the braiding process. The limitation of the yarn self-locking mechanism, which restricts the weaving angle to only between 15° and 70°, is overcome by independently winding 90° yarn layers, eliminating the weakness of the interlaced structure and enhancing the circumferential pressure-bearing capacity of the S-shaped air intake cylinder. This application reduces the areal density of the woven fabric by decreasing the degree of yarn crimp, thus reducing the mass of the S-shaped air intake cylinder. Furthermore, the winding of 90° yarn layers enhances the circumferential pressure-bearing capacity of the S-shaped air intake cylinder, eliminating the need to increase the number of layers to improve its pressure-bearing capacity, thereby reducing redundant layers and lowering the total thickness of the layers, further achieving lightweighting of the S-shaped air intake cylinder. This application utilizes a robot motion control system for automated weaving, enabling continuous fiber weaving without the need for fiber cutting and manual layering, effectively reducing production costs and improving production efficiency. The resulting S-shaped air intake cylinder combines high performance with lightweight characteristics.

[0043] The above description is merely an optional embodiment of this application and does not limit the patent scope of this application. Any equivalent structural transformations made based on the inventive concept of this application and the contents of the specification and drawings of this application, or direct / indirect applications in other related technical fields, are included within the patent protection scope of this application.

Claims

1. A unidirectional weaving method for a composite material S-shaped air intake cylinder, characterized in that, The method comprises the following steps: a core module is designed according to the geometric shape of the S-shaped air inlet duct cylinder, and a running track generatrix of the core module is designed; a two-dimensional braiding machine and a single yarn winding machine are controlled according to the design requirements of the ply angle of the S-shaped air inlet duct cylinder, and the core module is driven to reciprocate along the running track generatrix by a robot motion control system, so that a unidirectional braided layer and a 90° yarn layer are respectively coated on the surface of the core module to obtain a braided preform; the braided preform is subjected to vacuum infusion, resin curing and demolding treatment to obtain a finished S-shaped air inlet duct cylinder.

2. The unidirectional braiding method of a composite S-duct cylinder according to claim 1, wherein, In the step of designing the running track generatrix of the core module, the running track generatrix of the core module is extracted by CATIA software, and a braiding point and a single yarn winding point are positioned on the running track generatrix; the braiding point is the position where the yarn is deposited on the surface of the core module after the yarn is interwoven to form a fabric in the two-dimensional braiding machine, and the single yarn winding point is the position where the yarn of the single yarn winding machine is deposited on the surface of the core module.

3. The method of uni-directional braiding of a composite S-duct cylinder of claim 2, wherein, The step of driving the core module to reciprocate along the running track generatrix by the robot motion control system comprises: discrete point coordinates of the running track generatrix are extracted and imported into the robot motion control system; the core module is driven to reciprocate along the running track generatrix by the robot motion control system; when the core module runs along the running track generatrix, the line connecting the cross-sectional center of the core module at the braiding point and the center of the track disc of the two-dimensional braiding machine is the normal line of the track disc plane of the two-dimensional braiding machine; when the core module runs along the running track generatrix, the cross-sectional center of the core module at the single yarn winding point coincides with the center of the track disc of the single yarn winding machine.

4. The method of claim 1, wherein the composite S-duct cylinder is formed by a single direction weaving process. The step of controlling the process parameters of the two-dimensional braiding machine and the single yarn winding machine to respectively coat the unidirectional braided layer and the 90° yarn layer on the surface of the core module comprises: the rotational speed of the two-dimensional braiding machine and the movement speed of the core module are adjusted according to the design requirements of the braiding angle, and the two-dimensional braiding machine coats the unidirectional braided layer on the surface of the core module; the rotational speed of the single yarn winding machine is adjusted to control the yarn of the single yarn winding machine to be wound vertically to the axial direction of the core module to form the 90° yarn layer on the surface of the core module.

5. The method of claim 4, wherein the composite S-duct cylinder is formed by a single direction weaving process. The unidirectional braided layer comprises a first unidirectional braided layer and a second unidirectional braided layer; when the core module advances along the running track generatrix, the first unidirectional braided layer is coated on the surface of the core module, and the load-bearing yarn of the first unidirectional braided layer comprises 0° yarn parallel to the axis of the core module and diagonal yarn at a +θ° angle with the axis of the core module; when the core module retreats along the running track generatrix, the second unidirectional braided layer is coated on the surface of the core module, and the load-bearing yarn of the second unidirectional braided layer comprises 0° yarn parallel to the axis of the core module and diagonal yarn at a -θ° angle with the axis of the core module; wherein the advancing speed of the core module is the same as the retreating speed, and θ is the braiding angle.

6. The method of uni-directional braiding of a composite S-duct cylinder of claim 1, wherein, The yarns of the unidirectional braided layer include reinforcing yarns, axial yarns and auxiliary yarns; The cross-sectional area of the auxiliary yarns is less than 1 / 30 of the cross-sectional area of the reinforcing yarns; The number ratio of the reinforcing yarns to the auxiliary yarns is (1-3):1; The number ratio of the reinforcing yarns to the axial yarns is one of 1:1, 2:1, 4:1 or 8:

1.

7. The method of uni-directional braiding of a composite S-duct cylinder of claim 6, wherein, The reinforcing yarns and the axial yarns are the same type of carbon fiber yarns, and the auxiliary yarns are nylon yarns.

8. The method of uni-directional braiding of a composite S-duct cylinder of claim 1, wherein, The step of obtaining the finished S-shaped air inlet duct cylinder after the braided preform is subjected to vacuum infusion, resin curing and demolding treatment, comprises: After the two ends of the braided preform are cut and cleaned, peelable cloth and flow guide net are laid on the outer periphery, a glue injection port is arranged below the braided preform, a glue outlet port is arranged above the braided preform, and a sealing bag is used for wrapping, and then vacuum is drawn; When the vacuum degree is not less than -0.095 MPa within 25-30 min, glue injection is performed through the glue injection port until resin flows out of the glue outlet port, and the flowing resin is bubble-free for 10-15 min, and the glue injection is completed; After the braided preform after glue injection is cured, it is cooled to room temperature, demolding is performed, and the finished S-shaped air inlet duct cylinder is obtained.

9. A unidirectional braiding apparatus for a composite S-duct cylinder, characterized by, A unidirectional braiding method for implementing the composite S-shaped air inlet duct cylinder of any one of claims 1-8, the unidirectional braiding device comprising: A two-dimensional braiding machine that coats the unidirectional braided layer on the surface of the braiding core mold; A single yarn winding machine located in front of the two-dimensional braiding machine, which winds a 90° yarn layer perpendicular to the axial direction of the braiding core mold on the surface of the braiding core mold; A robot motion control system connected with the two-dimensional braiding machine, the single yarn winding machine and the braiding core mold respectively, which can adjust the process parameters of the two-dimensional braiding machine and the single yarn winding machine, and control the braiding core mold to reciprocate along the running trajectory generatrix.

10. The unidirectional braiding apparatus for a composite S-duct cylinder of claim 9, wherein, The robot motion control system comprises a KUKA 6-axis robot, the end of which is connected with the braiding core mold to drive the braiding core mold to reciprocate along the running trajectory generatrix.

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