A test device and method for optimizing prepreg tow splicing process parameters

Abstract

This invention discloses an experimental apparatus and method for optimizing prepreg splicing process parameters. The experimental apparatus includes a first splicing module, a second splicing module, a lifting module, a testing module, and an electrical and control system. The lifting module moves the first splicing module vertically up and down. The second splicing module is located directly below the first splicing module, and the testing modules are located on both sides of the second splicing module. The electrical and control system is electrically connected to each module. When studying the process parameters, the optimization goal is to achieve the highest splicing efficiency while meeting splicing quality requirements. Test tensile force is selected as the characterization parameter, and splicing pressure, splicing temperature, splicing time, and splicing size are selected as factor variables for iterative optimization until suitable process parameters are obtained. The experimental apparatus provided by this invention has adjustable process parameters, and the tensile force value can be tested after splicing. A detailed optimization process for prepreg splicing process parameters is also provided.

Description

Technical Field

[0001] This invention relates to, but is not limited to, the field of automated fiber placement technology for composite prepregs, and particularly to an experimental apparatus and method for optimizing the splicing process parameters of prepreg bundles. Background Technology

[0002] Resin-based composite materials possess high specific strength, high specific stiffness, unique designability, and good processability, making them widely used in aerospace, defense, and civilian fields. Among these, resin-based composite prepreg tows are extensively used in composite winding and layup processes. This involves weaving reinforcing fibers into a fabric-like fiber reinforcement and immersing it in a resin matrix solvent. The resin matrix content in the reinforcing fibers is controlled through several processes, followed by drying and cutting to ultimately obtain the resin-based composite prepreg tow. In the winding process using an automatic fiber placement machine, producing a single part requires thousands of meters of prepreg tape. However, current winding equipment can only handle a maximum prepreg tape length of 300 meters. Therefore, the prepreg tow needs to be spliced ​​and continued during the winding process to complete the winding process.

[0003] With the advancement of aerospace vehicle design and manufacturing technology, there is a need to minimize the performance deviation of wound products. Manual sewing methods can no longer meet the requirements for the quality and efficiency of prepreg splicing.

[0004] Using equipment to complete the splicing of prepreg tows is currently the mainstream trend. During the splicing process, the main process parameters affecting the splicing quality of prepreg tows include splicing pressure, splicing temperature, splicing time, and splicing dimensions. Therefore, in order to improve the splicing quality and efficiency of prepreg tows, and to achieve the highest splicing efficiency while meeting the splicing quality requirements, an experimental device and method for studying the process parameters of prepreg tow splicing are designed. Summary of the Invention

[0005] The purpose of this invention is to solve the above-mentioned technical problems. This invention provides an experimental device and method for optimizing the splicing process parameters of prepreg tow, so as to solve the problem that the manual sewing method of prepreg tow is difficult to meet the splicing quality and production efficiency of prepreg tow.

[0006] The technical solution of the present invention: The present invention provides a test device for optimizing the process parameters of prepreg splicing, comprising: a first splicing module 1, a second splicing module 2, a lifting module 3, a testing module 4, an electrical and control system 5, and a moving cabinet 18;

[0007] The lowering block 10 of the second filament splicing module 2 is fixedly installed on the table of the mobile cabinet 18 through the mounting base plate 20, the lifting module 3 is fixedly installed on the mounting base plate 20, and the first filament splicing module 1 is installed on the lifting mechanism of the lifting module 3 through its connecting plate 9.

[0008] The upper pressure block 6, which is fixedly connected to the lower part of the connecting plate 9 in the first filament splicing module 1, is opposite to the lower pressure block 10, which is installed on the upper end face of the mounting base plate 20 in the second filament splicing module 2. The boss provided on the lower end face of the upper pressure block 6 matches the groove provided on the upper end face of the lower pressure block 10. It is used to place the prepreg filament 19 to be spliced ​​between the lower pressure block 10 and the upper pressure block 6. The upper pressure block 6 and the lower pressure block 10 are respectively provided with heating modules.

[0009] The upgrading mechanism of the lifting module 3, and the heating modules of the first filament splicing module 1 and the second filament splicing module 2 are respectively connected to the electrical and control system 5. The electrical and control system 5 is used to control the heating temperature and heating time of the heating module on the upper pressure block 6 and the lower pressure block 10, and to control the lifting module 3 to perform lifting motion, so as to drive the first filament splicing module 1 to move up and down in the vertical direction, and to control the lifting module 3 to move down until the first filament splicing module 1 is in close contact with the second filament splicing module 2 through the prepreg filament 19 and squeezes the prepreg filament 19 according to the set splicing pressure.

[0010] The mounting base plate 20 is provided with test modules 4 at both ends of the lower pressure block 10, which are used to clamp the two ends of the prepreg bundle 19 placed on the lower pressure block 10 through the clamping heads 15 at the inner ends of the two test modules 4; the two test modules 4 are respectively connected to the electrical and control system 5.

[0011] The electrical and control system 5 is also used to control the two test modules 4 that hold the two ends of the prepreg bundle 19 to move in opposite directions until the prepreg bundle 19 is broken, thereby testing the measured tensile force value of the spliced ​​prepreg bundle 19.

[0012] Optionally, in the experimental device for optimizing the splicing process parameters of prepreg bundles as described above, the lifting module 3 includes: a guide rail 11, a lead screw 12, a slider 13, a servo motor 14, and a U-shaped mounting bracket;

[0013] The mounting frame is mounted on the mounting base plate 20 of the first wire bundle splicing module 1 with its U-shaped bottom end plate. The top end plate of the U-shaped structure is fixed with a mounting servo motor 14. The guide rail 11 is vertically fixed on the back plate of the mounting frame. The lead screw 12 is vertically arranged between the top end plate and the bottom end plate of the mounting frame, and the top end of the lead screw 12 is connected to the servo motor 14. The slider 13 is connected to the lead screw 12 through its internal thread. The slider 13 is slidably mounted on the guide rail 11 through its inner end face, and the connecting plate 9 in the first wire bundle splicing module 1 is fixedly mounted through its outer end face.

[0014] The lifting module 3 is used to drive the lead screw 12 to rotate via the servo motor 14, converting the rotation of the lead screw 12 into the lifting motion of the slider 13, thereby driving the first filament splicing module 1 to move up and down in the vertical direction at a set speed, and applying a set splicing pressure to the prepreg filament 19 placed on the lower pressure block 10 in the second filament splicing module 2.

[0015] Optionally, in the test apparatus for optimizing the prepreg splicing process parameters as described above, the first splicing module 1 includes: an upper pressure block 6, an upper heating module 7a, a pressure sensor 8, and a connecting plate 9.

[0016] The connecting plate 9 is an L-shaped connecting plate. One side plate is fixedly installed on the slider 13 of the lifting module 3, and the lower end face of the other side plate is connected to the upper pressure block 6 by multiple screws. The pressure sensor 8 is located directly above the upper pressure block 6, and the upper and lower end faces of the pressure sensor 8 are connected to the connecting plate 9 and the upper pressure block 6, respectively. The bottom end face of the upper pressure block 6 is provided with a pressure block boss, and the interior of the upper pressure block 6 is set as a cavity structure. The upper heating module 7a is installed in the cavity structure inside the upper pressure block 6.

[0017] The upper heating module 7a and the pressure sensor 8 are respectively connected to the electrical and control system 5, and are used to control the upper heating module 7a to heat the upper pressure block 6 through the electrical and control system 5, and transmit the pressure information collected by the pressure sensor 8 to the electrical and control system 5 in real time.

[0018] Optionally, in the test apparatus for optimizing the splicing process parameters of prepreg bundles as described above, the second bundle splicing module 2 includes: a lower pressure block 10 and a lower heating module 7b;

[0019] The lower pressure block 10 is fixedly installed on the mounting base plate 20. The upper end face of the lower pressure block 10 is provided with a pressure block groove. The interior of the lower pressure block 10 is set as a cavity structure. The lower heating module 7b is installed in the cavity structure inside the lower pressure block 10.

[0020] The lower heating module 7b is connected to the electrical and control system 5 and is used to control the lower heating module 7b to heat the lower pressure block 10 through the electrical and control system 5.

[0021] Optionally, in the test apparatus for optimizing the splicing process parameters of prepreg tow as described above, each of the test modules 4 includes: a clamping head 15, a force sensor 16, and a moving mechanism 17.

[0022] Each of the test modules 4 is installed in the groove of the mounting base plate 20 via its moving mechanism 17, and the two test modules 4 are symmetrically arranged at both ends of the second filament splicing module 2;

[0023] In each of the test modules 4, a force sensor 16 is fixedly installed on the inner end face of the moving mechanism 17, and a clamping head 15 is connected through the force sensor 16. The clamping head 15 clamps one end of the spliced ​​prepreg bundle 19.

[0024] The two moving mechanisms 17 and force sensors 16 in the test modules 4 are respectively connected to the electrical and control system 5. The electrical and control system 5 controls the two moving mechanisms 17 to move in opposite directions, so as to drive the force sensor 16 and the clamping head 15 to move in opposite directions until the prepreg bundle 19 is broken. The force sensor 16 tests the measured tensile force value of the prepreg bundle 19 and feeds the measured tensile force value back to the electrical and control system 5.

[0025] Optionally, in the test apparatus for optimizing the splicing process parameters of prepreg tow as described above, the electrical and control system 5 is installed entirely inside the mobile cabinet 18;

[0026] The electrical and control system 5 is used to set test parameters for splicing and tensile tests, control the movement of each module to perform splicing of the prepreg bundle 19 according to the set test parameters, and obtain the measured tensile value of the prepreg bundle 19 after splicing, and collect test data during the test; wherein, the test parameters set by the electrical and control system 5 include splicing pressure, splicing temperature and splicing time.

[0027] Optionally, in the test apparatus for optimizing the splicing process parameters of prepreg bundles as described above, the test apparatus is equipped with multiple sets of upper pressure blocks 6 and lower pressure blocks 10 arranged in pairs;

[0028] The specifications of the multiple sets of upper pressure blocks 6 and lower pressure blocks 10 are set according to the size of the prepreg bundles to be spliced.

[0029] Secondly, embodiments of the present invention also provide a test method for optimizing the splicing process parameters of prepreg tow, wherein the test apparatus for optimizing the splicing process parameters of prepreg tow 19 is used as described in any of the above embodiments to perform the splicing process parameter optimization test method on the prepreg tow 19, the test method comprising:

[0030] Step 1: Select splicing pressure, splicing temperature, splicing time, and splicing size as factor variables, and select test tensile force as the characterization parameter of the test;

[0031] Step 2: Set the value range and initial value for each factor variable, and set the test tensile force F; where the value range and initial value for each factor variable are as follows: splicing pressure p: [p1, pn], pn; splicing temperature t: [t1, tn], tn; splicing time s: [s1, sn], s1; splicing size k: [k1, kn], k1; each factor variable is set with n experimental values ​​within its value range;

[0032] Step 3, the splicing test and tensile test of the prepreg tow, includes: selecting the test value of each factor variable for the splicing test, splicing two prepreg tows with their adhesive surfaces facing each other, connecting the outer ends of each prepreg tow to the clamping heads 15 at the inner ends of the corresponding test modules 4, and overlapping the inner ends of each prepreg tow with the other prepreg tow according to the initial value of the splicing size, and keeping the two sides of the two prepreg tows aligned after splicing. The electrical and control system 5 controls the upgrade module 3 to drive the first tow splicing module 1 to press down to complete the splicing and then rise. The electrical and control system 5 controls the two test modules 4 to automatically and synchronously move slowly to both sides until the two prepreg tows are broken to obtain the measured tensile force value Fi; wherein, in the first test, the initial value of each factor variable is selected as the test value for this test;

[0033] Step 4, iterative optimization of splicing test and tensile test, includes: by comparing the measured tensile value Fi obtained in this test with the set test tensile force F, adjusting at least one factor variable, and repeating the test process of step 3 to obtain the measured tensile value Fi that is closest to the test tensile force F.

[0034] Optionally, in the automated splicing method for prepreg towed composite materials as described above, step 4 includes:

[0035] If the test tensile force value Fi < F obtained in this test, the test in step 3 is repeated by sequentially increasing at least one factor variable among the splicing size and splicing time until the test tensile force value Fi > F. Then the process parameters of the current test are determined as the optimal splicing process parameters that meet the conditions.

[0036] If the test tensile force value Fi > F obtained in this test, the test in step 3 is repeated by successively decreasing at least one of the splicing pressure and splicing temperature variables until the test tensile force value Fi < F. Then, the process parameters of the previous test are determined as the optimal splicing process parameters that meet the conditions.

[0037] Optionally, in the automatic splicing method for prepreg bundles of composite materials as described above, when the two ends of the prepreg bundles to be spliced ​​do not overlap and are in the form of end face splicing;

[0038] The k value of the splicing size is set to 0, and the splicing size is always 0 during the iterative optimization process in step 4.

[0039] The beneficial effects of this invention: This invention provides a testing device and method for optimizing prepreg splicing process parameters. On one hand, by controlling the heating temperature and heating time of the upper pressure block 6 and lower pressure block 10 of the heating modules in the first and second prepreg splicing modules 1 and 2, precise control of splicing temperature and time is achieved. On the other hand, by controlling the lifting module 3 to perform lifting motion, the first prepreg splicing module 1 moves vertically up and down, and the lifting module 3 moves downward until the first prepreg splicing module 1 is in close contact with the second prepreg splicing module 2 through the prepreg and the prepreg is squeezed according to the set splicing pressure, precise control of splicing pressure is achieved. Furthermore, through the matching boss and groove structures in the upper pressure block 6 and lower pressure block 10, and the scale lines on the lower pressure block 10, precise control of the prepreg splicing dimensions is achieved during the test. Compared with existing prepreg sewing methods, the technical solution provided by this invention has the following beneficial effects:

[0040] (1) The test device and method for optimizing the process parameters of prepreg splicing provided in the embodiments of the present invention can be precisely set by the test device for each process parameter (including splicing pressure, splicing temperature, splicing time and splicing size) during the splicing process.

[0041] (2) The experimental method for optimizing the splicing process parameters of prepreg bundles provided in the embodiments of the present invention provides a detailed iterative optimization process for the splicing process parameters of prepreg bundles, which solves the balance between splicing efficiency and overlapping quality. The best splicing process parameters that meet the performance indicators and splicing efficiency can be found through iterative optimization.

[0042] (3) The test apparatus and method for optimizing the splicing process parameters of prepreg bundles provided by the present invention can be applied to optimize the splicing process parameters of prepreg bundles with different widths and specifications, and can also be applied to optimize the splicing process parameters when the splicing size is 0, with wide applicability. Attached Figure Description

[0043] The accompanying drawings are provided to further understand the technical solutions of the present invention and constitute a part of the specification. They are used together with the embodiments of this application to explain the technical solutions of the present invention and do not constitute a limitation on the technical solutions of the present invention.

[0044] Figure 1 A schematic diagram of the overall structure of an experimental device for optimizing prepreg splicing process parameters provided in an embodiment of the present invention;

[0045] Figure 2 for Figure 1 The illustrated embodiment provides a schematic diagram of the combined structure of some modules in the experimental apparatus for optimizing prepreg splicing process parameters;

[0046] Figure 3 for Figure 2 The diagram shows the structure of the upper overlapping module in the filament overlapping module provided in the embodiment shown.

[0047] Figure 4 for Figure 2 The diagram shows the structure of the lower overlap module in the filament overlap module provided in the embodiment shown.

[0048] Figure 5 A schematic diagram of the installation structure of another test device for optimizing prepreg splicing process parameters provided in an embodiment of the present invention;

[0049] Figure 6 This is a flowchart of an automatic splicing method for prepreg bundles of composite materials, provided as an embodiment of the present invention.

[0050] Explanation of reference numerals in the attached figures:

[0051] 1. First filament splicing module; 2. Second filament splicing module; 3. Lifting module; 4. Testing module; 5. Electrical and control system; 6. Upper pressure block; 7a. Upper heating module; 7b. Lower heating module; 8. Pressure sensor; 9. Connecting plate; 10. Lower pressure block; 11. Guide rail; 12. Lead screw; 13. Slider; 14. Servo motor; 15. Clamping head; 16. Force sensor; 17. Moving mechanism; 18. Moving cabinet; 19. Prepreg filament; 20. Mounting base plate. Detailed Implementation

[0052] To make the objectives, technical solutions, and advantages of the present invention clearer, the embodiments of the present invention will be described in detail below with reference to the accompanying drawings. It should be noted that, unless otherwise specified, the embodiments and features described in this application can be arbitrarily combined with each other.

[0053] The background section has already explained the advantages of composite materials and their widespread application, as well as the overlapping requirements and existing overlapping methods for prepreg tows in practical applications. Currently, prepreg tows are overlapped via manual sewing, resulting in low overlapping efficiency. Furthermore, the sewing thread at the prepreg tow joint becomes a contaminant during the winding process, and the pinholes created on the prepreg tow during sewing form stress concentration points. The presence of these contaminants and stress concentration points causes the actual performance of the composite material parts to deviate from the design performance, resulting in poor product consistency and increased manufacturing costs.

[0054] With the advancement of aerospace composite manufacturing technology, there is a need to reduce the performance deviation of composite parts. To address this need, this invention provides an experimental device and method for optimizing the splicing process parameters of prepreg bundles, so as to achieve high-quality and rapid splicing of prepreg bundles.

[0055] The present invention provides the following specific embodiments, which can be combined with each other. For the same or similar concepts or processes, they may not be described again in some embodiments.

[0056] Figure 1 This is a schematic diagram of the overall structure of an experimental device for optimizing prepreg splicing process parameters, provided in an embodiment of the present invention. Figure 2 for Figure 1 The illustrated embodiment provides a schematic diagram of the combined structure of some modules in the experimental apparatus for optimizing prepreg splicing process parameters. Figure 2 The diagram illustrates the first filament splicing module 1, the second filament splicing module 2, the lifting module 3, the testing module 4, and the mounting base plate 20 in the experimental setup. (Refer to...) Figure 1 and Figure 2 As shown, the overall structure of the test device for optimizing prepreg splicing process parameters provided in this embodiment of the invention includes: a first splicing module 1, a second splicing module 2, a lifting module 3, a testing module 4, an electrical and control system 5, and a moving cabinet 18.

[0057] like Figure 1 and Figure 2 In the overall structure of the experimental device shown, the second filament splicing module 2 is fixedly installed on the table of the mobile cabinet 18 via the mounting base plate 20, the lifting module 3 is fixedly installed on the mounting base plate 20, and the first filament splicing module 1 is installed on the lifting mechanism of the lifting module 3 via its connecting plate 9.

[0058] like Figure 1 and Figure 2As shown, the upper pressure block 6, which is fixedly connected below the connecting plate 9 in the first filament splicing module 1, is opposite to the lower pressure block 10, which is installed on the upper end face of the mounting base plate 20 in the second filament splicing module 2. The pressure block boss on the lower end face of the upper pressure block 6 matches the pressure block groove on the upper end face of the lower pressure block 10, and is used to place the prepreg filaments 19 to be spliced ​​between the lower pressure block 10 and the upper pressure block 6.

[0059] like Figure 1 and Figure 2 As shown, the upgrading mechanism of the lifting module 3, and the heating modules of the first filament splicing module 1 and the second filament splicing module 2 are respectively connected to the electrical and control system 5. In this embodiment of the invention, the electrical and control system 5 is used to control the heating temperature and heating time of the upper pressure block 6 and the lower pressure block 10 by the heating module, and to control the lifting module 3 to perform lifting movements, thereby driving the first filament splicing module 1 to move vertically up and down, and to control the lifting module 3 to move downwards until the first filament splicing module 1 is in close contact with the second filament splicing module 2 through the pre-impregnated filament 19 and presses the pre-impregnated filament 19 according to the set splicing pressure, thereby realizing the splicing operation of the pre-impregnated filament 19.

[0060] In this embodiment of the invention, the structure and size of the pressing boss of the upper pressing block 6 in the first filament splicing module 1 and the pressing groove of the lower pressing block 10 in the second filament splicing module 2 are matched, and both can be used with the heating module to realize the function of synchronously heating the upper and lower surfaces of the pre-impregnated filament bundle 19.

[0061] like Figure 1 and Figure 2 As shown, the mounting base plate 20 is provided with test modules 4 at both ends of the lower pressure block 10, which are used to clamp the two ends of the prepreg bundle 19 placed on the lower pressure block 10 through the clamping heads 15 at the inner ends of the two test modules 4 respectively; the two test modules 4 are respectively connected to the electrical and control system 5.

[0062] Accordingly, the electrical and control system 5 in this embodiment of the invention is also used to control the two test modules 4 that hold the two ends of the prepreg bundle 19 to move in opposite directions until the prepreg bundle 19 is broken, thereby testing the measured tensile force value of the spliced ​​prepreg bundle 19.

[0063] In one implementation of this invention, a possible structure for the lifting module is provided, such as... Figure 3 As shown, Figure 2 The illustrated embodiment provides a schematic diagram of the combined structure of the first filament splicing module and the lifting module in the experimental apparatus for optimizing prepreg splicing process parameters. The lifting module 3 in this implementation includes: a guide rail 11, a lead screw 12, a slider 13, a servo motor 14, and a mounting bracket.

[0064] like Figure 2 and Figure 3 As shown, the mounting frame is mounted on the mounting base plate 20 of the first wire bundle splicing module 1 with its U-shaped bottom end plate. The mounting servo motor 14 is fixed on the top end plate of the U-shaped structure. The guide rail 11 is vertically fixed on the back plate of the mounting frame. The lead screw 12 is vertically arranged between the top end plate and the bottom end plate of the mounting frame, and the top end of the lead screw 12 is connected to the servo motor 14. The slider 13 is connected to the lead screw 12 through its internal thread. The slider 13 is slidably mounted on the guide rail 11 through its inner end face, and the connecting plate 9 in the first wire bundle splicing module 1 is fixedly mounted through its outer end face.

[0065] In this implementation, the lifting module 3 functions as follows: the servo motor 14 drives the lead screw 12 to rotate, converting the rotation of the lead screw 12 into the lifting motion of the slider 13, thereby driving the first filament splicing module 1 to move up and down in the vertical direction at a set speed, and applying a set splicing pressure to the pre-impregnated filament placed on the lower pressure block 10 in the second filament splicing module 2.

[0066] In one implementation of this invention, a possible structure for the first filament splicing module is provided, such as... Figure 3 As shown, the first filament splicing module 1 in this implementation includes: an upper pressure block 6, an upper heating module 7a, a pressure sensor 8, and a connecting plate 9.

[0067] like Figure 3 As shown, the connecting plate 9 is an L-shaped connecting plate. One side plate is fixedly installed on the slider 13 of the lifting module 3, and the lower end face of the other side plate is connected to the upper pressure block 6 by multiple screws. The pressure sensor 8 is located directly above the upper pressure block 6, and the upper and lower end faces of the pressure sensor 8 are connected to the connecting plate 9 and the upper pressure block 6, respectively. The bottom end face of the upper pressure block 6 is provided with a pressure block boss, and the interior of the upper pressure block 6 is set as a cavity structure. The upper heating module 7a is installed in the cavity structure inside the upper pressure block 6. In specific implementation, the surface material of the pressure block boss is polytetrafluoroethylene, and the width of the pressure block boss is the same as the width of the filament bundle.

[0068] In this implementation, the upper heating module 7a and the pressure sensor 8 are respectively connected to the electrical and control system 5, which is used to control the upper heating module 7a to heat the upper pressure block 6 through the electrical and control system 5, and to transmit the pressure information collected by the pressure sensor 8 to the electrical and control system 5 in real time.

[0069] In one implementation of this invention, a possible structure for the second filament overlap module is provided, such as... Figure 4 As shown, Figure 2The illustrated embodiment provides a schematic diagram of the combined structure of the second filament overlap module and the testing module in the experimental apparatus for optimizing prepreg splicing process parameters. The second filament overlap module 2 in this implementation includes: a lower pressure block 10 and a lower heating module 7b.

[0070] like Figure 4 As shown, the lower pressure block 10 is fixedly installed on the mounting base plate 20. The upper end face of the lower pressure block 10 is provided with a pressure block groove, and the interior of the lower pressure block 10 is set as a cavity structure. The lower heating module 7b is installed in the cavity structure inside the lower pressure block 10. In a specific implementation, the inner surface material of the pressure block groove is polytetrafluoroethylene.

[0071] In this implementation, the lower heating module 7b is connected to the electrical and control system 5, and is used to control the lower heating module 7b to heat the lower pressure block 10 through the electrical and control system 5.

[0072] In one implementation of this invention, a possible implementation structure for the test module is provided, such as... Figure 4 As shown, each test module 4 includes: a clamping head 15, a force sensor 16, and a moving mechanism 17.

[0073] like Figure 4 As shown, each test module 4 is installed in the groove of the mounting base plate 20 via its moving mechanism 17, and two test modules 4 are symmetrically arranged at both ends of the second filament splicing module 2. In each test module 4, a force sensor 16 is fixedly installed on the inner end face of the moving mechanism 17, and a clamping head 15 is connected through the force sensor 16. The clamping head 15 clamps one end of the spliced ​​prepreg filament 19.

[0074] In this implementation, the moving mechanism 17 and force sensor 16 in the two test modules 4 are respectively connected to the electrical and control system 5. The electrical and control system 5 controls the two moving mechanisms 17 to move in opposite directions, which can drive the force sensor 16 and the clamping head 15 to move in opposite directions until the prepreg bundle 19 is broken. The force sensor 16 tests the measured tensile force value of the prepreg bundle 19 and feeds the measured tensile force value back to the electrical and control system 5.

[0075] In one implementation of this invention, a possible structure for the second filament overlap module is provided, such as... Figure 1 As shown, the electrical and control system 5 is installed inside the mobile cabinet 18, and it is electrically connected to the electrical components in the first wire bundle splicing module 1, the second wire bundle splicing module 2, the lifting module 3, and the testing module 4. The electrical components in each module that are specifically connected to the electrical and control system 5 have been described in the above embodiments.

[0076] In this implementation, the electrical and control system 5 is used to set the test parameters for splicing and tensile tests, control the movement of each module to perform splicing of the prepreg bundle 19 according to the set test parameters, and obtain the measured tensile value of the prepreg bundle 19 after splicing, and collect the test data in the test.

[0077] It should be noted that the test parameters set by the electrical and control system 5 include splicing pressure, splicing temperature, and splicing time; in addition, the test parameters also include the splicing dimensions of the two prepreg bundles 19 during manual splicing operations.

[0078] In addition, it should be noted that in the preferred implementation of the present invention, the test device is usually configured with multiple sets of upper pressure blocks 6 and lower pressure blocks 10 arranged in pairs;

[0079] The specifications of the multiple sets of upper pressure blocks 6 and lower pressure blocks 10 are set according to the size of the prepreg bundles to be spliced; in specific installation, the upper pressure block 6 is connected to the connecting plate 9 by screws, and the lower pressure block 10 is connected to the mounting base plate 20 by screws, which facilitates disassembly and replacement.

[0080] Based on the experimental apparatus for optimizing prepreg splicing process parameters provided in the above embodiments of the present invention, the present invention also provides an experimental method for optimizing prepreg splicing process parameters. The experimental apparatus for optimizing prepreg splicing process parameters provided in any of the above embodiments can be used to optimize the splicing process parameters of the prepreg tow, such as... Figure 5 The diagram shows a flowchart of an experimental method for optimizing prepreg splicing process parameters according to an embodiment of the present invention. This experimental method may include the following steps:

[0081] Step 1: With the goal of achieving the highest splicing efficiency while meeting splicing quality requirements, splicing pressure, splicing temperature, splicing time, and splicing size are selected as factor variables, and test tensile force is selected as the characterization parameter of the experiment. The test tensile force is a fixed value F in a set of experiments.

[0082] Step 2: Set the range and initial value for each factor variable, and set the test tension F.

[0083] In this step, the range and initial value of each factor variable are set as follows: splicing pressure p: [p1, pn], pn; splicing temperature t: [t1, tn], tn; splicing time s: [s1, sn], s1; splicing size k: [k1, kn], k1; each factor variable is set with n experimental values ​​within its range.

[0084] It should be noted that, considering average quality and splicing efficiency, the initial values ​​of splicing pressure and splicing temperature are set to the maximum values ​​within their respective ranges, while the initial values ​​of splicing time and splicing size are set to the minimum values ​​within their respective ranges. Furthermore, the intervals between adjacent test values ​​of the above-mentioned factor variables can be equal, for example, Δp, Δt, Δs, and Δk respectively; the intervals between different factor variables can also be set according to preset rules. Moreover, the test tensile force F is determined by multiplying the actual tension value of the pre-impregnated yarn bundle during the placement process (i.e., the tension value of the automatic yarn placer) by a safety factor.

[0085] Step 3, the splicing test and tensile test of the prepreg tow, includes: selecting the test value of each factor variable for the splicing test, splicing two prepreg tows with their adhesive surfaces facing each other, connecting the outer ends of each prepreg tow to the clamping heads 15 at the inner ends of the corresponding test modules 4, and overlapping the inner ends of each prepreg tow with the other prepreg tow according to the initial value of the splicing size, and keeping the two sides of the two prepreg tows aligned after splicing. The electrical and control system 5 controls the upgrade module 3 to drive the first tow splicing module 1 to press down to complete the splicing and then lift it up. The electrical and control system 5 controls the two test modules 4 to automatically and synchronously move slowly to both sides until the two prepreg tows are broken to obtain the measured tensile force value Fi.

[0086] It should be noted in this step that in the first experiment of a set of optimization experiments, the initial value of each factor variable is selected as the experimental value for this experiment.

[0087] Step 4, iterative optimization of splicing test and tensile test, includes: by comparing the measured tensile value Fi obtained in this test with the set test tensile force F, adjusting at least one factor variable, and repeating the test process of step 3 to obtain the measured tensile value Fi that is closest to the test tensile force F.

[0088] In a specific implementation of this invention, step 4, the iterative optimization process, specifically includes:

[0089] If the tensile force Fi obtained in this experiment is less than F, it means that the process parameters for this experiment do not meet the requirements. The experiment in step 3 is repeated by sequentially increasing at least one factor variable among the splicing size and splicing time until the tensile force Fi > F. Then, the process parameters of the current experiment are determined as the optimal splicing process parameters that meet the conditions. It should be noted that the preferred iterative optimization scheme is to change only one factor variable in each experiment, with the two factor variables increasing alternately.

[0090] If the test tensile force value Fi > F obtained in this test, it means that the process parameters of this test can meet the requirements, but are not the optimal parameters for work efficiency. By successively decreasing at least one factor variable among splicing pressure and splicing temperature, the test in step 3 is repeated until the test tensile force value Fi < F. Then, the process parameters of the previous test are determined as the optimal splicing process parameters that meet the conditions.

[0091] In one implementation of the present invention, when the two ends of the prepreg bundles to be spliced ​​do not overlap and are in the form of end-face splicing, for example, the cross-sections of the ends of the two prepreg bundles are spliced, or the splicing ends of the two prepreg bundles form a complementary inclined structure, in the above cases, the thickness of the splicing area of ​​the spliced ​​prepreg bundles is the same as the thickness of a single prepreg bundle.

[0092] In this implementation, the value of k for the splicing size is a constant and is not used as a factor variable. Alternatively, it can be understood as setting the value of k for the splicing size to 0, i.e., k1, kn, and Δk are all 0. During the iterative optimization process in step 4, the splicing size is always 0.

[0093] It should be noted that, in the embodiments of the present invention, the ranges of splicing pressure, splicing temperature, splicing time, and splicing size can be determined according to actual needs and by consulting relevant literature.

[0094] The experimental apparatus and method for optimizing prepreg splicing process parameters provided in this invention embodiment achieve precise control of splicing temperature and time by controlling the heating temperature and heating time of the upper pressure block 6 and lower pressure block 10 in the first and second filament splicing modules 1 and 2, respectively. Furthermore, precise control of splicing pressure is achieved by controlling the lifting module 3 to perform lifting motion, thereby moving the first filament splicing module 1 vertically up and down, and controlling the lifting module 3 to move downwards until the first filament splicing module 1 is in close contact with the second filament splicing module 2 through the prepreg filaments and compressing the prepreg filaments according to a set splicing pressure. Additionally, precise control of the prepreg filament splicing dimensions is achieved through the matching boss and groove structures in the upper pressure block 6 and lower pressure block 10, as well as the scale lines on the lower pressure block 10. Compared with existing prepreg filament splicing methods, the technical solution provided in this invention embodiment has the following beneficial effects:

[0095] (1) The test device and method for optimizing the process parameters of prepreg splicing provided in the embodiments of the present invention can be precisely set by the test device for each process parameter (including splicing pressure, splicing temperature, splicing time and splicing size) during the splicing process.

[0096] (2) The experimental method for optimizing the splicing process parameters of prepreg bundles provided in the embodiments of the present invention provides a detailed iterative optimization process for the splicing process parameters of prepreg bundles, which solves the balance between splicing efficiency and overlapping quality. The best splicing process parameters that meet the performance indicators and splicing efficiency can be found through iterative optimization.

[0097] (3) The test apparatus and method for optimizing the splicing process parameters of prepreg bundles provided by the present invention can be applied to optimize the splicing process parameters of prepreg bundles with different widths and specifications, and can also be applied to optimize the splicing process parameters when the splicing size is 0, with wide applicability.

[0098] While the embodiments disclosed in this invention are as described above, they are merely illustrative of the embodiments to facilitate understanding of the invention and are not intended to limit the invention. Any person skilled in the art may make any modifications and variations in the form and details of the implementation without departing from the spirit and scope disclosed herein; however, the scope of patent protection of this invention shall still be determined by the scope defined in the appended claims.

Claims

1. An experimental apparatus for optimizing prepreg splicing process parameters, characterized in that, include: The system comprises a first wire bundle splicing module (1), a second wire bundle splicing module (2), a lifting module (3), a testing module (4), an electrical and control system (5), and a mobile cabinet (18). Among them, the pressing block (10) of the second filament splicing module (2) is fixedly installed on the table of the mobile cabinet (18) through the mounting base plate (20), the lifting module (3) is fixedly installed on the mounting base plate (20), and the first filament splicing module (1) is installed on the lifting mechanism of the lifting module (3) through its connecting plate (9). The upper pressure block (6) fixedly connected below the connecting plate (9) in the first filament splicing module (1) is opposite to the lower pressure block (10) installed on the upper end face of the mounting base plate (20) in the second filament splicing module (2). The boss provided on the lower end face of the upper pressure block (6) matches the groove provided on the upper end face of the lower pressure block (10), which is used to place the prepreg filament (19) to be spliced ​​between the lower pressure block (10) and the upper pressure block (6). The upper pressure block (6) and the lower pressure block (10) are respectively provided with heating modules. The upgrading mechanism of the lifting module (3), and the heating modules of the first filament splicing module (1) and the second filament splicing module (2) are respectively connected to the electrical and control system (5); the electrical and control system (5) is used to control the heating temperature and heating time of the heating module on the upper pressure block (6) and the lower pressure block (10), and to control the lifting module (3) to perform lifting motion so as to drive the first filament splicing module (1) to move up and down in the vertical direction, and to control the lifting module (3) to move down until the first filament splicing module (1) is close to the second filament splicing module (2) through the prepreg filament (19) and squeezes the prepreg filament (19) according to the set splicing pressure; The mounting base plate (20) is provided with test modules (4) at both ends of the lower pressure block (10), which are used to clamp the two ends of the prepreg bundle (19) placed on the lower pressure block (10) through the clamping heads (15) at the inner ends of the two test modules (4); the two test modules (4) are respectively connected to the electrical and control system (5); The electrical and control system (5) is also used to control the two test modules (4) that hold the two ends of the prepreg bundle (19) to move in opposite directions until the prepreg bundle (19) is broken, so as to test the measured tensile value of the spliced ​​prepreg bundle (19).

2. The experimental apparatus for optimizing prepreg splicing process parameters according to claim 1, characterized in that, The lifting module (3) includes: a guide rail (11), a lead screw (12), a slider (13), a servo motor (14), and a U-shaped mounting bracket; The mounting frame is mounted on the mounting base plate (20) of the first wire bundle splicing module (1) with its U-shaped bottom end plate. The top end plate of the U-shaped structure is fixed with a mounting servo motor (14). The guide rail (11) is vertically fixed on the back plate of the mounting frame. The lead screw (12) is vertically set between the top end plate and the bottom end plate of the mounting frame. The top end of the lead screw (12) is connected to the servo motor (14). The slider (13) is connected to the lead screw (12) through its internal thread. The slider (13) is slidably mounted on the guide rail (11) through its inner end face and the connecting plate (9) in the first wire bundle splicing module (1) is fixedly mounted through its outer end face. The lifting module (3) is used to drive the lead screw (12) to rotate via the servo motor (14), converting the rotation of the lead screw (12) into the lifting motion of the slider (13), thereby driving the first filament splicing module (1) to move up and down in the vertical direction at a set speed, and applying a set splicing pressure to the prepreg filament (19) placed on the lower pressure block (10) in the second filament splicing module (2).

3. The experimental apparatus for optimizing prepreg splicing process parameters according to claim 2, characterized in that, The first filament splicing module (1) includes: an upper pressure block (6), an upper heating module (7a), a pressure sensor (8), and a connecting plate (9); The connecting plate (9) is configured as an L-shaped connecting plate. One side plate is fixedly installed on the slider (13) of the lifting module (3), and the lower end face of the other side plate is connected to the upper pressure block (6) by multiple screws. The pressure sensor (8) is located directly above the upper pressure block (6), and the upper and lower end faces of the pressure sensor (8) are connected to the connecting plate (9) and the upper pressure block (6) respectively. The bottom end face of the upper pressure block (6) is provided with a pressure block boss. The interior of the upper pressure block (6) is configured as a cavity structure, and the upper heating module (7a) is installed in the cavity structure inside the upper pressure block (6). The upper heating module (7a) and the pressure sensor (8) are respectively connected to the electrical and control system (5) for controlling the upper heating module (7a) to heat the upper pressure block (6) through the electrical and control system (5) and transmitting the pressure information collected by the pressure sensor (8) to the electrical and control system (5) in real time.

4. The experimental apparatus for optimizing prepreg splicing process parameters according to claim 3, characterized in that, The second filament splicing module (2) includes: a lower pressure block (10) and a lower heating module (7b); The lower pressure block (10) is fixedly installed on the mounting base plate (20). The upper end face of the lower pressure block (10) is provided with a pressure block groove. The interior of the lower pressure block (10) is set as a cavity structure. The lower heating module (7b) is installed in the cavity structure inside the lower pressure block (10). The lower heating module (7b) is connected to the electrical and control system (5) and is used to control the lower heating module (7b) to heat the lower pressure block (10) through the electrical and control system (5).

5. The experimental apparatus for optimizing prepreg splicing process parameters according to any one of claims 1 to 4, characterized in that, Each of the test modules (4) includes: a clamping head (15), a force sensor (16), and a moving mechanism (17); Each of the test modules (4) is installed in the groove of the mounting base plate (20) via its moving mechanism (17), and the two test modules (4) are symmetrically arranged at both ends of the second filament splicing module (2); In each of the test modules (4), a force sensor (16) is fixedly installed on the inner end face of the moving mechanism (17), and a clamping head (15) is connected through the force sensor (16) to clamp one end of the spliced ​​prepreg bundle (19). The moving mechanism (17) and force sensor (16) in the two test modules (4) are respectively connected to the electrical and control system (5) for controlling the two moving mechanisms (17) to move in opposite directions through the electrical and control system (5) to drive the force sensor (16) and the clamping head (15) to move in opposite directions until the prepreg bundle (19) is broken. The force sensor (16) tests the measured tensile force value of the prepreg bundle (19) and feeds back the measured tensile force value to the electrical and control system (5).

6. The experimental apparatus for optimizing prepreg splicing process parameters according to any one of claims 1 to 4, characterized in that, The electrical and control system (5) is installed inside the mobile cabinet (18); The electrical and control system (5) is used to set test parameters for splicing and tensile tests, control the movement of each module to perform splicing of the prepreg bundle (19) according to the set test parameters, and obtain the measured tensile value of the prepreg bundle (19) after splicing, and collect test data in the test; wherein, the test parameters set by the electrical and control system (5) include splicing pressure, splicing temperature and splicing time.

7. The experimental apparatus for optimizing prepreg splicing process parameters according to any one of claims 1 to 4, characterized in that, The test apparatus is equipped with multiple sets of upper pressure blocks (6) and lower pressure blocks (10) arranged in pairs; The specifications of the multiple sets of upper pressure blocks (6) and lower pressure blocks (10) are set according to the size of the prepreg bundles to be spliced.

8. A test method for optimizing prepreg tow splicing process parameters, characterized in that, The prepreg (19) is subjected to an optimization test of splicing process parameters using the test apparatus for optimizing prepreg splicing process parameters as described in any one of claims 1 to 7, the test method comprising: Step 1: Select splicing pressure, splicing temperature, splicing time, and splicing size as factor variables, and select test tensile force as the characterization parameter of the test; Step 2: Set the value range and initial value for each factor variable, and set the test tensile force F; where the value range and initial value for each factor variable are as follows: splicing pressure p: [p1, pn], pn; splicing temperature t: [t1, tn], tn; splicing time s: [s1, sn], s1; splicing size k: [k1, kn], k1; each factor variable is set with n experimental values ​​within its value range; Step 3, splicing test and tensile test of prepreg bundles, including: selecting the test value of each factor variable for splicing test, splicing two prepreg bundles with their adhesive surfaces facing each other, connecting the outer end of each prepreg bundle to the clamping head (15) of the inner end of the test module (4) at the corresponding position, and overlapping the inner end of each prepreg bundle with the other prepreg bundle according to the initial value of the splicing size, and keeping the two sides of the two prepreg bundles aligned after splicing, controlling the lifting module (3) through the electrical and control system (5) to drive the first bundle splicing module (1) to press down to complete the splicing and then lift up, controlling the two test modules (4) through the electrical and control system (5) to automatically and synchronously move slowly to both sides until the two prepreg bundles are broken to obtain the measured tensile value Fi; wherein, the initial value of each factor variable is selected as the test value of this test in the first test; Step 4, iterative optimization of splicing test and tensile test, includes: by comparing the measured tensile value Fi obtained in this test with the set test tensile force F, adjusting at least one factor variable, and repeating the test process of step 3 to obtain the measured tensile value Fi that is closest to the test tensile force F.

9. The experimental method for optimizing prepreg splicing process parameters according to claim 8, characterized in that, Step 4 includes: If the test tensile force value Fi < F obtained in this test, the test in step 3 is repeated by sequentially increasing at least one factor variable among the splicing size and splicing time until the test tensile force value Fi > F. Then the process parameters of the current test are determined as the optimal splicing process parameters that meet the conditions. If the test tensile force value Fi > F obtained in this test, the test in step 3 is repeated by successively decreasing at least one of the splicing pressure and splicing temperature variables until the test tensile force value Fi < F. Then, the process parameters of the previous test are determined as the optimal splicing process parameters that meet the conditions.

10. The experimental method for optimizing prepreg splicing process parameters according to claim 8, characterized in that, When the two ends of the prepreg bundles to be spliced ​​do not overlap, and it is an end-face splicing form; The k value of the splicing size is set to 0, and the splicing size is always 0 during the iterative optimization process in step 4.

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