An on-line thickness detection device for high performance composite material prepreg tape forming process

Abstract

The application belongs to the technical field of prepreg tape production, and particularly relates to an online thickness detection device in a high-performance composite material prepreg tape forming process, which comprises detection racks arranged side by side on both sides of a prepreg tape preparation machine; first and second scanning laser testers are respectively arranged between the two detection racks to measure the surface distance difference of the prepreg tape and calculate the thickness; U-shaped racks are connected to the two sides of the two detection racks below the prepreg tape, the inner wall of the U-shaped rack is connected with a pressure-resistant box, and a first flat plate is clamped in the port at the top of the pressure-resistant box; in the application, the repeatability and accuracy of the thickness data are significantly improved through the cooperation of the double laser testers, uniform negative pressure adsorption and dynamic stable voltage control, the "large-hole anti-blocking" and "small-hole anti-fluctuation" modes are automatically switched according to the state of the prepreg tape, the anti-blocking ability and the flutter suppression effect are taken into account, and continuous production and high-precision control are ensured.

Description

Technical Field

[0001] This invention belongs to the field of prepreg production technology, specifically an online thickness detection device for the molding process of high-performance composite prepreg tape. Background Technology

[0002] During laser triangulation thickness measurement, if the prepreg tape vibrates (commonly referred to in the industry as "chatter" or "jumping"), the reflected light from its surface will deviate from the ideal geometric path, thus directly causing measurement errors.

[0003] Existing technologies disclose several invention patents in the field of prepreg production technology. Among them, utility model patent with publication number CN222652153U discloses a prepreg thickness detection mechanism, including a lower detection component and an upper detection component. The upper detection component is bolted to one side of the top outer wall of the lower detection component. The lower detection component includes a base plate, a lower measuring module, a lead screw, a clamping block, a rubber pad, and a handle. A groove is formed on one side of the top outer wall of the base plate. The lower measuring module is bolted into the bottom outer wall of the base plate near the groove. The upper detection component includes a mounting frame, an upper measuring module, a mounting rod, a lower guide roller, a lead screw, a connecting rod, an upper guide roller, a handle, and a sliding frame. During detection, the lower and upper measuring modules, which are infrared laser ranging sensors, can detect the distance between the bottom and top surfaces of the prepreg and the base plate and the inner wall of the top of the mounting frame. The thickness of the prepreg can be obtained by subtracting the values. This process is not affected by vibration and can improve the accuracy of the detection results.

[0004] During the thickness detection of prepreg tape, the prepreg tape is sequentially sent to the laser thickness detection area of ​​the thickness detection equipment via a transmission device. The thickness of the prepreg tape is detected by a laser sensor. During the detection, the prepreg tape may slightly arch, causing the reflected light to deviate from the original path. This deviation in the reflection angle will cause the signal received by the laser sensor to change, which may lead to deviations in the measurement data.

[0005] Based on this, the present invention designs an online thickness detection device for the molding process of high-performance composite prepreg tape to solve the above problems. Summary of the Invention

[0006] To overcome the shortcomings of existing technologies, this invention proposes an online thickness detection device for the molding process of high-performance composite prepreg tape. This invention primarily addresses the problem that during prepreg tape thickness detection, the prepreg tape is sequentially fed to the laser thickness detection area of ​​the thickness detection device via a transmission device. The laser sensor then detects the thickness of the prepreg tape. During detection, the prepreg tape may slightly arch, causing the reflected light to deviate from its intended path. This deviation in reflection angle alters the signal received by the laser sensor, potentially leading to inaccurate measurement data.

[0007] The technical solution adopted by the present invention to solve its technical problem is: an online thickness detection device in the molding process of high-performance composite prepreg tape, including detection frames arranged side by side on both sides of the prepreg tape preparation machine; a first scanning laser tester and a second scanning laser tester are respectively installed between the two detection frames to measure the distance difference between the surfaces of the prepreg tape and calculate the thickness; Both sides of the two test frames are connected to U-shaped frames below the prepreg belt. The inner wall of the U-shaped frame is connected to a pressure-resistant box. A first flat plate is snapped into the port at the top of the pressure-resistant box. The first flat plate has multiple micro-holes. The bottom of the two pressure-resistant boxes is connected to a shunt pipe. The two shunt pipes are connected to each other through a three-phase connector. A vacuum pump is installed between the two test frames. The other end of the three-phase connector is connected to the output end of the vacuum pump through a gas supply pipe. A vacuum regulating valve is installed on the gas supply pipe. The testing frame has a base connected to the bottom of each of the two corresponding U-shaped frames. A third electric cylinder is installed on the base, and the telescopic end of the third electric cylinder is connected to the bottom of the corresponding U-shaped frame.

[0008] Preferably, the inner wall of the pressure-resistant box is slidably connected to a second flat plate, the first flat plate is also provided with a plurality of micro holes, the second flat plate is connected to a plurality of sealing shafts corresponding to the plurality of micro holes, the plurality of sealing shafts are respectively sealed and connected to the plurality of micro holes, and the second flat plate is provided with a plurality of first air holes.

[0009] Preferably, the inner wall of the pressure-resistant box is slidably connected to a third flat plate below the second flat plate. The top of the third flat plate is connected to multiple compensation tubes corresponding to multiple micro-holes. The combination of the inner circular surface of the multiple compensation tubes and the inner circular surface of the multiple micro-holes is the same as the inner circular surface of the multiple micro-holes. The second flat plate is also provided with multiple bridging holes. The multiple compensation tubes are slidably connected in the multiple bridging holes respectively. The top of the compensation tube is located between the first flat plate and the second flat plate. The third flat plate is also provided with multiple second air holes.

[0010] Preferably, a fourth flat plate is snapped onto the inner wall of the pressure-resistant box below the second flat plate, and a first electric cylinder is installed on the fourth flat plate, with the telescopic end of the first electric cylinder connected to the bottom of the third flat plate; The fourth planar plate has multiple flow equalization holes, and the outlet of the flow divider is located below the fourth planar plate.

[0011] Preferably, the bottom of the second flat plate is connected to a first toothed plate, a reverse gear is meshed on the tooth surface of the first toothed plate, a gear shaft is rotatably connected to the pressure box, the reverse gear is fixedly sleeved on the other end of the gear shaft, a second toothed plate is also meshed on the tooth surface of the reverse gear, and the bottom of the second toothed plate is connected to the top of the third flat plate.

[0012] Preferably, sealing strips are slidably connected to both sides of the top of the first flat plate, and straight modules are installed on the U-shaped frame corresponding to the two sealing strips. A sliding seat is provided on the straight module, and a bend shaft is connected to the top of the sliding seat. The other end of the bend shaft is connected to one end of the sealing strip.

[0013] Preferably, a fixed shaft is provided on both sides of the pressure-resistant box on the U-shaped frame, a fixed plate is fixedly sleeved on the other end of the fixed shaft, a spring is sleeved on the fixed shaft, and a movable plate is connected to the other end of the spring. The movable plate is rotatably connected to the fixed shaft. A take-up roller connected to a movable disc is rotatably connected to the fixed shaft. A sealing strip is wound around the take-up roller, and the other end of the sealing plug is connected to a corresponding sealing strip.

[0014] Preferably, each of the two sealing strips is rotatably connected to a pressure roller, which moves the sealing strip against the top of the first flat plate. Both ends of the pressure roller are rotatably connected to an L-shaped frame, and the bottom of the two L-shaped frames are connected to the top of the pressure-resistant box. The edges on both sides of the top of the pressure-resistant box are rounded.

[0015] Preferably, the bottom of the pressure-resistant box is connected to a pressure-stabilizing cylinder, a piston head is slidably connected inside the pressure-stabilizing cylinder, an annular groove is formed on the circumferential surface of the piston head, a sealing ring is fixedly sleeved on the piston head by an annular sleeve, and a second electric cylinder is installed in the inner bottom of the pressure-stabilizing cylinder, the telescopic end of the second electric cylinder is connected to the bottom of the piston head; A piezoresistive sensor is installed on the pressure-resistant box.

[0016] The beneficial effects of this invention are as follows: 1. In this invention, the repeatability and accuracy of thickness data are significantly improved by using dual laser testers in synergy, negative pressure uniform adsorption and dynamic pressure stabilization control. The system automatically switches between "large hole anti-clogging" and "small hole anti-fluctuation" modes according to the state of the prepreg tape, taking into account both anti-clogging capability and chatter suppression effect, ensuring continuous production and high-precision control.

[0017] 2. In this invention, the linear module drives the sealing strip to automatically adapt to prepreg tapes of different widths, reducing air leakage, enhancing adsorption, suppressing edge warping, and improving the stability of the detection area.

[0018] 3. In this invention, the movement of the sealing strip drives the sealing tape to be automatically released and retracted without the need for additional power, reducing air leakage loss, improving negative pressure utilization efficiency, and simplifying the system structure.

[0019] 4. In this invention, based on the closed-loop control of the piezoresistive sensor and the second electric cylinder, the negative pressure fluctuations are quickly suppressed, ensuring constant adsorption force, improving dynamic response capability, and reducing energy consumption and wear of the vacuum system.

[0020] 5. In this invention, the uniform and controllable adsorption force avoids indentation, resin seepage, sliding or stretching, thus protecting the original structure and surface quality of the prepreg tape. Attached Figure Description

[0021] The invention will now be further described with reference to the accompanying drawings.

[0022] Figure 1 This is a schematic diagram of the overall structure of the present invention; Figure 2 This is a top-view schematic diagram of the planar structure of the present invention; Figure 3 This is a three-dimensional structural diagram of the present invention viewed from below; Figure 4 This is a structural schematic diagram of the pressure-resistant box in this invention from another perspective; Figure 5 This is a cross-sectional structural schematic diagram of the pressure-resistant box in this invention; Figure 6 This is the present invention. Figure 4 A schematic diagram of the disassembled structure; Figure 7 This is a cross-sectional view of the pressure-resistant box in this invention from another perspective; Figure 8 This is the present invention. Figure 6 Enlarged structural diagram at point A in the middle.

[0023] In the diagram: 1. Testing frame; 2. First scanning laser tester; 3. Second scanning laser tester; 4. U-shaped frame; 5. Pressure-resistant box; 6. First flat plate; 7. Micro-hole; 8. Diverter pipe; 9. Gas supply pipe; 10. Vacuum regulating valve; 11. Vacuum pump; 12. Second flat plate; 13. Sealing shaft; 14. First air hole; 15. Third flat plate; 16. Compensation pipe; 17. Second air hole; 18. Fourth flat plate; 19. First electric cylinder; 20. First gear plate; 21. Reverse gear; 22. Gear 23. Shaft; 24. Second toothed face plate; 25. Sliding seat; 26. Bent shaft; 27. Sealing strip; 28. L-shaped frame; 29. ​​Pressure roller; 30. Fixed shaft; 31. Fixed disc; 32. Movable disc; 33. Spring; 34. Take-up roller; 35. Sealing strip; 36. Piezoresistive sensor; 37. Pressure stabilizing cylinder; 38. Piston head; 39. Sealing ring; 40. Second electric cylinder; 41. Third electric cylinder; 42. Base; 43. Flow equalization hole; 44. Linear module; 45. Micro-hole; 46. Three-phase connector; 47. Bridging hole. Detailed Implementation

[0024] To make the technical means, creative features, objectives and effects of this invention easier to understand, the invention will be further described below in conjunction with specific embodiments.

[0025] like Figures 1 to 8 As shown, an online thickness detection device for the molding process of high-performance composite prepreg tape includes detection frames 1 arranged side by side on both sides of the prepreg tape preparation machine; a first scanning laser tester 2 and a second scanning laser tester 3 are respectively installed between the two detection frames 1 to measure the distance difference between the surfaces of the prepreg tape and calculate the thickness. Two test frames 1 are connected to U-shaped frames 4 on both sides below the prepreg belt. Pressure-resistant boxes 5 are connected to the inner wall of the U-shaped frames 4. A first flat plate 6 is snapped into the port at the top of the pressure-resistant box 5. Multiple micro holes 7 are opened on the first flat plate 6. The bottom of the two pressure-resistant boxes 5 are connected to the shunt pipes 8. The two shunt pipes 8 are connected to each other through a three-phase connector 45. A vacuum pump 11 is set between the two test frames 1. The other end of the three-phase connector 45 is connected to the output end of the vacuum pump 11 through a gas supply pipe 9. A vacuum regulating valve 10 is installed on the gas supply pipe 9. The test frame 1 has a base 41 connected to the bottom of each of the two corresponding U-shaped frames 4. A third electric cylinder 40 is installed on the base 41, and the telescopic end of the third electric cylinder 40 is connected to the bottom of the corresponding U-shaped frame 4.

[0026] Specifically, in this embodiment, during the production of prepreg tape by the prepreg tape preparation machine, the thickness detection is performed collaboratively by the first scanning laser tester 2 and the second laser tester after precise light alignment. During thickness detection, the two sides of the prepreg tape's detection area are stably moved against the upper surfaces of the two first planar plates 6. The system starts the vacuum pump 11, which sequentially pumps air through the gas supply pipe 9, the three-phase connector 45, and the two shunt pipes 8 to evacuate the interiors of the two pressure-resistant boxes 5, bringing them to a near-vacuum state. Due to the arrangement of the shunt pipes 8... At the bottom of the pressure-resistant box 5, the negative pressure environment created inside the pressure-resistant box 5 causes the air near the bottom of the first flat plate 6 to flow sequentially through multiple first air holes 14, multiple second air holes 17, and multiple flow equalization holes 42, before converging into the distribution pipe 8 and being extracted. Thus, the negative pressure suction generated by the vacuum pump 11 acts uniformly on the lower surface of the prepreg tape through the aforementioned microporous structure 7. During this process, the system also precisely adjusts and stabilizes the negative pressure suction intensity acting on the lower surface of the prepreg tape by controlling the vacuum regulating valve 10, thereby ensuring that the prepreg tape maintains its pressure during the testing process. Maintaining a flat and stable posture, the negative pressure is uniformly applied to the lower surface of the prepreg tape through the micropore structure 7 on the first planar plate 6, effectively eliminating local warping or vibration of the material during transmission. This provides a stable and flat detection reference surface for the first scanning laser tester 2 and the second laser tester, thereby improving the repeatability and accuracy of thickness data. The vacuum regulating valve 10 actively adjusts and stabilizes the negative pressure suction intensity acting on the lower surface of the prepreg tape, avoiding frictional resistance caused by excessively tight adhesion due to negative pressure fluctuations, or insufficient adhesion to suppress vibration. To ensure a continuous and reliable production process, the design of bottom-mounted diverter 8 and pre-vacuuming of pressure-resistant box 5 guides the airflow along the low-resistance path of first air hole 14, second air hole 17, flow equalization hole 42, and diverter 8, reducing pressure loss. This allows the negative pressure generated by vacuum pump 11 to be more efficiently converted into uniform adsorption force on the prepreg tape. Uniform and controllable negative pressure adsorption avoids excessive local suction force causing indentations or resin seepage on the surface of the uncured prepreg tape. At the same time, it prevents the material from sliding or stretching during the testing process, protecting the original structure and surface integrity of the product.

[0027] Specifically, the inner wall of the pressure-resistant box 5 is slidably connected to a second flat plate 12, and a number of micro holes 44 are also provided on the first flat plate 6. A number of sealing shafts 13 are connected to the second flat plate 12 corresponding to the number of micro holes 44. The number of sealing shafts 13 are respectively sealed and connected to the number of micro holes 44. A number of first air holes 14 are provided on the second flat plate 12. The inner wall of the pressure-resistant box 5 is slidably connected to a third flat plate 15 below the second flat plate 12. The top of the third flat plate 15 is connected to multiple micro-holes 7 and multiple compensation tubes 16. The combination of the inner circular surface of the multiple compensation tubes 16 and the inner circular surface of the multiple micro-holes 44 is the same as the inner circular surface of the multiple micro-holes 7. Multiple bridging holes 46 are also provided on the second flat plate 12. Multiple compensation tubes 16 are slidably connected in the multiple bridging holes 46 respectively. The top of the compensation tubes 16 is between the first flat plate 6 and the second flat plate 12. Multiple second air holes 17 are also provided on the third flat plate 15. The inner wall of the pressure-resistant box 5 is fitted with a fourth flat plate 18 below the second flat plate 12. A first electric cylinder 19 is installed on the fourth flat plate 18. The telescopic end of the first electric cylinder 19 is connected to the bottom of the third flat plate 15. The fourth planar plate 18 has multiple flow equalization holes 42, and the opening of the flow divider pipe 8 is located below the fourth planar plate 18. The bottom of the second flat plate 12 is connected to the first toothed plate 20. A reverse gear 21 is meshed on the tooth surface of the first toothed plate 20. A gear shaft 22 is rotatably connected to the pressure box 5. The reverse gear 21 is fixedly sleeved on the other end of the gear shaft 22. A second toothed plate 23 is also meshed on the tooth surface of the reverse gear 21. The bottom of the second toothed plate 23 is connected to the top of the third flat plate 15.

[0028] Specifically, in this embodiment, the aperture of the micropore 7 is larger than that of the micropore 44. During normal operation, negative pressure suction acts on the lower surface of the prepreg tape through the micropore 7. The larger aperture gives it a certain anti-clogging ability. When the system detects local warping or vibration of the prepreg tape during transmission, the first electric cylinder 19 is controlled to respond quickly. The telescopic end of the first electric cylinder 19 pushes the third flat plate 15 upward. The third flat plate 15 drives the second toothed plate 23 to move along the tooth surface of the reverse gear 21. Then, the reverse gear 21 drives the first toothed plate 20 to move downward, causing the second flat plate 12 to slide downward in the pressure box 5. Finally, the third flat plate... 15 drives multiple compensation tubes 16 to be inserted into multiple micro-holes 7 respectively, while the second flat plate 12 drives multiple sealing shafts 13 to disengage from multiple micro-holes 44 respectively. At this time, the flow cross section formed by the inner circular surface of each compensation tube 16 and the inner circular surface of the corresponding micro-hole 44 is consistent with the inner circular surface of the original micro-hole 7, that is, the total porosity acting on the bottom of the prepreg tape remains unchanged. In this state, since the micro-holes 44 have a stronger airflow throttling effect than the micro-holes 7, even if there is a slight negative pressure fluctuation inside the pressure box 5, the change in adsorption force after passing through the micro-holes 44 will be more gradual, which is more conducive to suppressing the flutter of the prepreg tape. After the transmission status stabilizes, the system controls the first electric cylinder 19 to retract, causing the compensation tube 16 to exit the micro-hole 7 and the sealing shaft 13 to re-seal the micro-hole 44. This restores the normal operating mode where negative pressure is applied to the lower surface of the prepreg tape through the micro-hole 7, thus continuously leveraging the anti-clogging advantage of the micro-hole 7. The system automatically switches between "large-hole anti-clogging mode" and "small-hole anti-fluctuation mode" based on the real-time status of the prepreg tape. This ensures the continuity of daily production while providing rapid response and proactive intervention in the event of flutter, balancing the dual requirements of stable operation and high-precision control. In the flutter suppression state, the stronger throttling effect of the micro-hole 44 is utilized to smooth and withstand... The negative pressure pulsation inside the pressure box 5 makes the adsorption force acting on the lower surface of the prepreg tape more stable, effectively suppressing local warping or vibration, and providing a more stable detection benchmark for laser thickness measurement. Through the combined design of the compensation tube 16 and the micro-hole 44, it is ensured that the total porosity acting on the bottom of the prepreg tape remains unchanged before and after the switch, avoiding sudden changes or uneven distribution of adsorption force caused by structural switching, and ensuring a smooth transition of the prepreg tape posture. Combined with the mechanical linkage mechanism of real-time detection and electric cylinder drive, closed-loop suppression of transmission disturbances is achieved, which significantly improves the equipment's adaptability to complex working conditions and reduces the risk of detection errors or production interruptions caused by material fluctuations.

[0029] Specifically, sealing strips 26 are slidably connected to both sides of the top of the first flat plate 6. A straight module 43 is installed on each of the two sealing strips 26 on the U-shaped frame 4. A sliding seat 24 is provided on the straight module 43. A bend shaft 25 is connected to the top of the sliding seat 24. The other end of the bend shaft 25 is connected to one end of the sealing strip 26.

[0030] In this specific implementation, the system automatically adjusts the spacing between the two sealing strips 26 according to the actual width of the prepreg tape to be tested. Specifically, the system simultaneously controls the operation of two linear modules 43. The linear modules 43 move by driving the sliding seat 24, which in turn drives the bend shaft 25. The bend shaft 25 then drives the sealing strip 26 to slide on the first flat plate 6 until the inner edge of the sealing strip 26 is precisely fitted with the side edge of the prepreg tape. Through this adaptive adjustment, the lateral movement space of the prepreg tape in the testing area can be effectively constrained, thereby improving the stability of the prepreg tape during transmission to a certain extent. The precise fit between the sealing strip 26 and the edge of the prepreg tape physically restricts the lateral movement of the prepreg tape, ensuring that it always stays within the laser measurement range. Within the effective measurement range of the instrument, a stable lateral positioning reference is provided for thickness detection. After the sealing strip 26 is attached to the edge of the prepreg tape, it can reduce air leakage in the area not covered by the prepreg tape on the first flat plate 6, so that the negative pressure generated by the vacuum pump 11 can be more concentrated and efficient on the lower surface of the prepreg tape, thereby improving the adsorption effect. Through the linkage control of the linear module 43, the sliding seat 24 and the corner shaft 25, the system can automatically adapt to different widths of prepreg tape specifications without manual intervention or replacement of parts, which improves the flexibility and automation level of the production line. The slight constraint of the sealing strip 26 on the edge of the prepreg tape can suppress edge lifting or curling caused by airflow disturbance or uneven tension, further ensuring the flat posture of the prepreg tape throughout the detection process.

[0031] Specifically, the U-shaped frame 4 is provided with fixed shafts 29 on both sides of the pressure box 5. The other end of the fixed shaft 29 is fixedly sleeved with a fixed plate 30. A spring 32 is sleeved on the fixed shaft 29. The other end of the spring 32 is connected to a movable plate 31. The movable plate 31 is rotatably connected to the fixed shaft 29. A take-up roller 33 connected to the movable disc 31 is rotatably connected to the fixed shaft 29. A sealing strip 34 is wound around the take-up roller 33. The other end of the sealing plug is connected to the corresponding sealing strip 26. Pressure rollers 28 are rotatably connected to both sealing strips 34 to move the sealing strips 34 against the top of the first flat plate 6. L-shaped frames 27 are rotatably connected to both ends of the pressure rollers 28. The bottom of both L-shaped frames 27 is connected to the top of the pressure box 5. Rounded corners are provided on both sides of the top of the pressure box 5.

[0032] Specifically, in this embodiment: during the sliding process of the sealing strip 26 on the first flat plate 6 driven by the linear module 43, the sealing strip 26 simultaneously pulls the sealing tape 34 connected to it. The sealing tape 34 is gradually released from the take-up roller 33, causing the take-up roller 33 to rotate around the fixed shaft 29. During this process, the take-up roller 33 twists the spring 32 on the fixed shaft 29 through the movable disc 31, causing it to undergo elastic deformation and thus storing mechanical energy. When the sealing strip 26 moves in the reverse direction, the spring 32 releases the stored elastic potential energy, driving the take-up roller 33 to rotate in the reverse direction, and tightly rewrap the previously released sealing tape 34 around its surface. Using this sealing tape 34, the micropores 7 and micro-holes 44 in the area not covered by the prepreg tape on the first sealing plate can be effectively sealed. Through the mechanical linkage between the sealing strip 26 and the sealing tape 34, the release of the sealing tape 34 and the... The retraction mechanism fully follows the movement of the sealing strip 26, requiring no additional drive or control. Its simple structure and reliable operation, along with the sealing strip 34 sealing the micropores 7 and 44 in the area not covered by the prepreg tape on the first sealing plate, significantly reduces air leakage in this area. This allows the negative pressure generated by the vacuum pump 11 to act more concentrated on the lower surface of the prepreg tape, thereby enhancing the adsorption effect and reducing energy consumption. In the flutter suppression mode, the 44 micropores play a crucial throttling role. The sealing strip 34's sealing of the micropores 7 and 44 in the non-working area ensures that the negative pressure airflow strictly follows the designed path, preventing weakening of the throttling effect or uneven adsorption due to bypass leakage. The automatic retraction of the sealing strip 34 is achieved by storing energy using the spring 32, eliminating the need for additional active components such as motors or cylinders, reducing system complexity and potential failure points, and facilitating daily maintenance and replacement.

[0033] Specifically, the bottom of the pressure-resistant box 5 is connected to a pressure-stabilizing cylinder 36, and a piston head 37 is slidably connected inside the pressure-stabilizing cylinder 36. An annular groove is opened on the circumferential surface of the piston head 37, and a sealing ring 38 is fixedly sleeved on the piston head 37 through an annular sleeve. A second electric cylinder 39 is installed in the inner bottom of the pressure-stabilizing cylinder 36, and the telescopic end of the second electric cylinder 39 is connected to the bottom of the piston head 37. A piezoresistive sensor 35 is installed on the pressure box 5.

[0034] Specifically, this implementation involves the following: When the piezoresistive sensor 35 detects fluctuations in the negative pressure environment inside the pressure-resistant box 5, the system controls the second electric cylinder 39 to respond quickly. The extension end of the second electric cylinder 39 applies precise pulling or pushing force to the piston head 37, driving the piston head 37 to make corresponding sliding adjustments within the pressure-stabilizing cylinder 36. By changing the effective volume within the pressure-stabilizing cylinder 36, the system dynamically compensates for pressure changes within the pressure-resistant box 5, thereby maintaining the stability of its internal negative pressure environment. Real-time monitoring by the piezoresistive sensor 35 and the rapid movement of the piston head 37 driven by the second electric cylinder 39 form a closed-loop control system. This system can proactively compensate for negative pressure fluctuations rather than passively accepting them, significantly improving the system's dynamic response capability and ensuring stable pressure resistance. The negative pressure environment of the pressure box 5 directly determines the constant adsorption force acting on the lower surface of the prepreg tape. This optimization ensures that the prepreg tape is always subject to stable and uniform adsorption constraints under conditions such as changes in transmission speed, material width switching, or external airflow interference. The stability of the negative pressure eliminates the small vibrations or posture changes of the prepreg tape caused by fluctuations in adsorption force, providing a long-term stable detection reference surface for the first scanning laser tester 2 and the second laser tester, thereby improving the repeatability and reliability of thickness data. The small-amplitude, high-frequency negative pressure fluctuations are smoothed out by the rapid fine adjustment of the pressure stabilizing cylinder 36 and the piston head 37, avoiding the additional energy consumption and wear caused by frequent start-stop or throttling adjustment of the vacuum pump 11, and extending the overall life of the vacuum system.

[0035] During operation, in the prepreg production process of the prepreg tape preparation machine, thickness detection is completed collaboratively by a first scanning laser tester 2 and a second laser tester after precise light alignment. During detection, the two sides of the detection area of ​​the prepreg tape are stably moved against the upper surfaces of two first planar plates 6 respectively. The system starts the vacuum pump 11, which sequentially pumps through the gas supply pipe 9, the three-phase connector 45, and two shunt pipes 8 to evacuate the inside of the two pressure-resistant boxes 5, making the inside of the pressure-resistant boxes 5 approach a vacuum state. The shunt pipes 8 are located on the pressure-resistant boxes. At the bottom of the pressure box 5, the negative pressure environment inside the pressure box 5 causes the air near the bottom of the first flat plate 6 to flow sequentially through multiple first air holes 14, multiple second air holes 17, and multiple flow equalization holes 42 before converging into the distribution pipe 8 and being extracted. Thus, the negative pressure suction generated by the vacuum pump 11 acts uniformly on the lower surface of the prepreg tape through the aforementioned microporous structure 7. During this process, the system also precisely adjusts and stabilizes the intensity of the negative pressure suction acting on the lower surface of the prepreg tape by controlling the vacuum regulating valve 10, ensuring that the prepreg tape is tested... Throughout the process, the device maintains a flat and stable posture. The micropore structure 7 on the first flat plate 6 applies negative pressure evenly to the lower surface of the prepreg tape, effectively eliminating local warping or vibration during material transport. This provides a stable and flat detection reference surface for the two scanning laser testers, thereby improving the repeatability and accuracy of thickness data. The vacuum regulating valve 10 actively adjusts and stabilizes the negative pressure suction intensity, avoiding frictional resistance caused by excessively tight adsorption of the prepreg tape due to negative pressure fluctuations, or insufficient adsorption to suppress vibration, ensuring continuous and reliable production. The bottom placement of the diversion pipe 8 and the pre-vacuum design of the pressure-resistant box 5 guide the airflow along the low-resistance path of the first air hole 14, the second air hole 17, the equalizing hole 42, and the diversion pipe 8, reducing pressure loss and making the negative pressure generated by the vacuum pump 11 more efficiently converted into uniform adsorption force. The uniform and controllable negative pressure adsorption avoids excessive local suction force causing indentations or resin seepage on the surface of the uncured prepreg tape, while preventing the material from sliding or stretching during the testing process, protecting the original structure and surface integrity of the product. The aperture of micropore 7 is larger than that of micropore 44. During normal operation, negative pressure suction acts on the lower surface of the prepreg tape through micropore 7. The larger aperture gives it a certain anti-clogging ability. When the system detects local warping or vibration of the prepreg tape during transmission, the first electric cylinder 19 is controlled to respond quickly: the telescopic end of the first electric cylinder 19 pushes the third flat plate 15 upward. The third flat plate 15 drives the second toothed plate 23 to move along the tooth surface of the reverse gear 21. Then, the reverse gear 21 drives the first toothed plate 20 to move downward, causing the second flat plate 12 to slide downward in the pressure box 5. Finally, the third flat plate 15 drives multiple repair plates to move downward. The compensation tubes 16 are inserted into multiple micro-holes 7, while the second planar plate 12 drives multiple sealing shafts 13 to disengage from multiple micro-holes 44. At this time, the flow cross-section formed by the inner circular surface of each compensation tube 16 and the inner circular surface of the corresponding micro-hole 44 is consistent with the inner circular surface of the original micro-hole 7, that is, the total porosity acting on the bottom of the prepreg tape remains unchanged. In this state, since the micro-holes 44 have a stronger airflow throttling effect than the micro-holes 7, even if there is a slight negative pressure fluctuation inside the pressure-resistant box 5, the change in adsorption force after passing through the micro-holes 44 will be more gradual, which is more conducive to suppressing the flutter of the prepreg tape. After the condition stabilizes, the system controls the first electric cylinder 19 to retract, causing the compensation tube 16 to exit the micro-hole 7 and the sealing shaft 13 to re-seal the micro-hole 44. This restores the normal operating mode of applying negative pressure to the lower surface of the prepreg tape through the micro-hole 7, thus continuously leveraging the anti-clogging advantage of the micro-hole 7. Based on the real-time status of the prepreg tape, the system automatically switches between "large-hole anti-clogging mode" and "small-hole anti-fluctuation mode," ensuring both the continuity of daily production and rapid response and proactive intervention in the event of flutter. This balances the dual requirements of stable operation and high-precision control. In the flutter suppression state, the stronger throttling effect of the micro-hole 44 is utilized to smooth the pressure resistance. The negative pressure pulsation inside box 5 makes the adsorption force acting on the lower surface of the prepreg tape more stable, effectively suppressing local warping or vibration, and providing a more stable detection benchmark for laser thickness measurement. Through the combined design of compensation tube 16 and micro-hole 44, it is ensured that the total porosity acting on the bottom of the prepreg tape remains unchanged before and after switching, avoiding sudden changes or uneven distribution of adsorption force caused by structural switching, and ensuring a smooth transition of the prepreg tape posture. Combined with the mechanical linkage mechanism of real-time detection and electric cylinder drive, closed-loop suppression of transmission disturbances is achieved, significantly improving the equipment's adaptability to complex working conditions and reducing the risk of detection errors or production interruptions caused by material fluctuations. The system automatically adjusts the spacing between the two sealing strips 26 according to the actual width of the prepreg tape to be tested. Specifically, the system simultaneously controls the operation of two linear modules 43. The linear modules 43 move by driving the sliding seat 24, which in turn drives the bend shaft 25. The bend shaft 25 then drives the sealing strip 26 to slide on the first flat plate 6 until the inner edge of the sealing strip 26 is precisely fitted with the side edge of the prepreg tape. Through this adaptive adjustment, the lateral movement space of the prepreg tape in the testing area can be effectively constrained, improving the stability of the prepreg tape during transmission. The precise fit between the sealing strip 26 and the edge of the prepreg tape physically restricts the lateral movement of the prepreg tape, ensuring that it is always within the effective measurement range of the laser tester. Within the range, it provides a stable lateral positioning reference for thickness detection. After the sealing strip 26 is attached to the edge of the prepreg tape, it can reduce air leakage in the area not covered by the prepreg tape on the first flat plate 6, so that the negative pressure generated by the vacuum pump 11 can be more concentrated and efficient on the lower surface of the prepreg tape, improving the adsorption effect. Through the linkage control of the linear module 43, the sliding seat 24 and the corner shaft 25, the system can automatically adapt to different widths of prepreg tape specifications without manual intervention or replacement of parts, improving the flexibility and automation level of the production line. The slight constraint of the sealing strip 26 on the edge of the prepreg tape can suppress edge lifting or curling caused by airflow disturbance or uneven tension, further ensuring the flat posture of the prepreg tape throughout the detection process. As the linear module 43 drives the sealing strip 26 to slide on the first flat plate 6, the sealing strip 26 simultaneously pulls the sealing tape 34 connected to it. The sealing tape 34 gradually releases from the take-up roller 33 and drives the take-up roller 33 to rotate around the fixed shaft 29. During this process, the take-up roller 33 twists the spring 32 on the fixed shaft 29 through the movable disc 31, causing it to undergo elastic deformation and thus storing mechanical energy. When the sealing strip 26 moves in the opposite direction, the spring 32 releases the stored elastic potential energy, driving the take-up roller 33 to rotate in the opposite direction, tightly wrapping the previously released sealing tape 34 back onto its surface. Using this sealing tape 34, the micropores 7 and micro-holes 44 in the area not covered by the prepreg tape on the first sealing plate can be effectively sealed. Through the mechanical linkage between the sealing strip 26 and the sealing tape 34, the sealing tape 34... The release and retraction of 4 follow the movement of the sealing strip 26 without the need for additional drive and control. The structure is simple and the operation is reliable. The sealing strip 34 seals the micropores 7 and micro-holes 44 in the non-covered area, which can significantly reduce air leakage loss. The negative pressure generated by the vacuum pump 11 is more concentrated on the lower surface of the prepreg, thereby enhancing the adsorption effect and reducing energy consumption. In the flutter suppression mode, the micro-holes 44 play a key throttling role. The sealing strip 34 seals the micropores 7 and micro-holes 44 in the non-working area, ensuring that the negative pressure airflow flows strictly according to the design path, avoiding the weakening of the throttling effect or the cause of uneven adsorption due to bypass leakage. The automatic retraction of the sealing strip 34 is achieved by using the spring 32 to store energy. There is no need to add active components such as motors or cylinders, which reduces the complexity of the system and the failure points, and facilitates daily maintenance and replacement. When the piezoresistive sensor 35 detects fluctuations in the negative pressure environment inside the pressure-resistant box 5, the system controls the second electric cylinder 39 to respond quickly: the telescopic end of the second electric cylinder 39 applies precise pulling or pushing force to the piston head 37, driving the piston head 37 to slide and adjust accordingly within the pressure-stabilizing cylinder 36. By changing the effective volume within the pressure-stabilizing cylinder 36, the system dynamically compensates for pressure changes within the pressure-resistant box 5, thereby maintaining the stability of its internal negative pressure environment. Real-time monitoring by the piezoresistive sensor 35 and the rapid movement of the piston head 37 driven by the second electric cylinder 39 form a closed-loop control system. This system can proactively compensate for negative pressure fluctuations rather than passively accepting them, significantly improving the system's dynamic response capability and stability. The negative pressure environment of the pressure-resistant box 5 directly determines the constant adsorption force acting on the lower surface of the prepreg tape. This optimization ensures that the prepreg tape is always subject to stable and uniform adsorption constraints under conditions such as changes in transmission speed, material width switching, or external airflow interference. The stability of the negative pressure eliminates the small vibrations or posture changes of the prepreg tape caused by fluctuations in adsorption force, providing a long-term stable detection reference surface for the two scanning laser testers, thereby improving the repeatability and reliability of thickness data. The small-amplitude, high-frequency negative pressure fluctuations are smoothed out by the rapid fine adjustment of the pressure stabilizing cylinder 36 and the piston head 37, avoiding the additional energy consumption and wear caused by frequent start-stop or throttling adjustment of the vacuum pump 11, and extending the overall life of the vacuum system.

[0036] The embodiments of the present invention have been described above with reference to the accompanying drawings. However, the present invention is not limited to the specific embodiments described above. The specific embodiments described above are merely illustrative and not restrictive. Those skilled in the art can make many other forms under the guidance of the present invention without departing from the spirit and scope of the claims. All of these forms are within the protection scope of the present invention.

Claims

1. An online thickness detection device for the molding process of high-performance composite prepreg tape, comprising detection frames arranged side-by-side on both sides of a prepreg tape preparation machine; characterized in that: A first scanning laser tester and a second scanning laser tester are respectively installed between the two test frames to measure the distance difference between the surfaces of the prepreg tape and calculate the thickness. Both sides of the two test frames are connected to U-shaped frames below the prepreg belt. The inner wall of the U-shaped frame is connected to a pressure-resistant box. A first flat plate is snapped into the port at the top of the pressure-resistant box. The first flat plate has multiple micro-holes. The bottom of the two pressure-resistant boxes is connected to a shunt pipe. The two shunt pipes are connected to each other through a three-phase connector. A vacuum pump is installed between the two test frames. The other end of the three-phase connector is connected to the output end of the vacuum pump through a gas supply pipe. A vacuum regulating valve is installed on the gas supply pipe. The testing frame has a base connected to the bottom of each of the two corresponding U-shaped frames. A third electric cylinder is installed on the base, and the telescopic end of the third electric cylinder is connected to the bottom of the corresponding U-shaped frame.

2. The online thickness detection device for the molding process of high-performance composite prepreg tape according to claim 1, characterized in that: The inner wall of the pressure-resistant box is slidably connected to a second flat plate. The first flat plate is also provided with multiple micro holes. The second flat plate is connected to multiple sealing shafts corresponding to the multiple micro holes. The multiple sealing shafts are respectively sealed and connected to the multiple micro holes. The second flat plate is provided with multiple first air holes.

3. The online thickness detection device for the high-performance composite prepreg tape molding process according to claim 2, characterized in that: The inner wall of the pressure-resistant box is slidably connected to a third flat plate below the second flat plate. The top of the third flat plate is connected to multiple micro-holes and multiple compensation tubes. The combination of the inner circular surface of the multiple compensation tubes and the inner circular surface of the multiple micro-holes is the same as the inner circular surface of the multiple micro-holes. The second flat plate is also provided with multiple bridging holes. The multiple compensation tubes are slidably connected in the multiple bridging holes respectively. The top of the compensation tube is located between the first flat plate and the second flat plate. The third flat plate is also provided with multiple second air holes.

4. The online thickness detection device for the molding process of high-performance composite prepreg tape according to claim 3, characterized in that: The inner wall of the pressure-resistant box is fitted with a fourth flat plate below the second flat plate. A first electric cylinder is installed on the fourth flat plate, and the telescopic end of the first electric cylinder is connected to the bottom of the third flat plate. The fourth planar plate has multiple flow equalization holes, and the outlet of the flow divider is located below the fourth planar plate.

5. The online thickness detection device for the molding process of high-performance composite prepreg tape according to claim 4, characterized in that: The bottom of the second flat plate is connected to a first toothed plate, and a reverse gear is meshed on the tooth surface of the first toothed plate. A gear shaft is rotatably connected to the pressure box, and the reverse gear is fixedly sleeved on the other end of the gear shaft. A second toothed plate is also meshed on the tooth surface of the reverse gear, and the bottom of the second toothed plate is connected to the top of the third flat plate.

6. The online thickness detection device for the molding process of high-performance composite prepreg tape according to claim 5, characterized in that: Both sides of the top of the first flat plate are slidably connected to sealing strips. A straight module is installed on each of the two sealing strips on the U-shaped frame. A sliding seat is provided on the straight module. A bend shaft is connected to the top of the sliding seat. The other end of the bend shaft is connected to one end of the sealing strip.

7. The online thickness detection device for the molding process of high-performance composite prepreg tape according to claim 6, characterized in that: The U-shaped frame is provided with fixed shafts on both sides of the pressure-resistant box. A fixed plate is fixedly sleeved on the other end of the fixed shaft. A spring is sleeved on the fixed shaft. The other end of the spring is connected to a movable plate. The movable plate is rotatably connected to the fixed shaft. A take-up roller connected to a movable disc is rotatably connected to the fixed shaft. A sealing strip is wound around the take-up roller, and the other end of the sealing plug is connected to a corresponding sealing strip.

8. The online thickness detection device for the molding process of high-performance composite prepreg tape according to claim 7, characterized in that: Both sealing strips are rotatably connected to pressure rollers to move the sealing strips against the top of the first flat plate. Both ends of the pressure rollers are rotatably connected to L-shaped frames, and the bottoms of the two L-shaped frames are connected to the top of the pressure-resistant box. The edges on both sides of the top of the pressure-resistant box are rounded.

9. The online thickness detection device for the molding process of high-performance composite prepreg tape according to claim 8, characterized in that: The bottom of the pressure-resistant box is connected to a pressure-stabilizing cylinder, and a piston head is slidably connected inside the pressure-stabilizing cylinder. An annular groove is opened on the circumferential surface of the piston head, and a sealing ring is fixedly sleeved on the piston head by an annular sleeve. A second electric cylinder is installed in the inner bottom of the pressure-stabilizing cylinder, and the telescopic end of the second electric cylinder is connected to the bottom of the piston head. A piezoresistive sensor is installed on the pressure-resistant box.

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