A side-pressing type paper core shaftless unwinding device and control system

Abstract

The application discloses a side-pressing and clamping type paper core shaftless unwinding device and a control system, which comprises a base, a PLC control end, a guide rod, a support arm, a first transmission mechanism, a second transmission mechanism and a floating support mechanism; the floating support mechanism is provided with an inner rotating shaft, an expansion block, a pressure sensor and a displacement sensor; the expansion block can be radially expanded to tightly adhere to the inner wall of the paper core; a self-adaptive closed-loop control system is further arranged, which comprises a sensing and detecting unit, a micro-displacement executing unit and a data processing unit; the inner wall trace data and the single-point clamping pressure data of the paper core are collected, the inner wall trace reconstruction and the clamping pressure decoupling analysis are completed; the first transmission mechanism adjusts the distance between the support arms to realize the preliminary clamping of the paper core; the second transmission mechanism drives the paper core to unwind; the floating support mechanism provides elastic buffering; the control system cooperatively adjusts each executing component, realizes the self-adaptive closed-loop unwinding with uniform clamping force, no slipping and no deformation of the paper core, and solves the defects of the existing device, such as unstable clamping, easy extrusion deformation of the paper core and no self-adaptive adjustment.

Description

Technical Field

[0001] This invention relates to the field of side-pressure shaftless unwinding device technology, and in particular to a side-pressure top-tightening shaftless unwinding device and control system for paper cores. Background Technology

[0002] Shaftless unwinding devices do not require paper core shafts and have strong adaptability, and are widely used in the paper product processing field. The side-pressure tightening shaftless unwinding device has become the mainstream type due to its compact structure and convenient operation. This type of device uses the side support structure to tighten the paper core laterally to complete the shaftless unwinding operation.

[0003] Existing side-pressure clamping shaftless unwinding devices generally adopt a single rigid clamping structure with a conical clamping block. They rely solely on the radial contact between the clamping block and the inner wall of the paper core to achieve fixation. The contact stability between the paper core and the clamping components is insufficient. During the unwinding process, relative slippage can easily occur due to tension fluctuations and changes in the paper roll diameter, affecting the unwinding accuracy.

[0004] The device uses a rigid clamping method. As the paper roll diameter gradually decreases, the continuous rigid clamping force causes the ends of the paper core to be squeezed and deformed, which is more serious for thin-walled and fragile paper cores. At the same time, the device lacks an adaptive adjustment function, cannot match the inner wall shape of the paper core, and cannot balance the single-point clamping pressure. The clamping uniformity is poor, which limits the applicability of the device and the overall unwinding quality. Summary of the Invention

[0005] The purpose of this invention is to overcome the shortcomings of the prior art by proposing a side-pressure tightening type shaftless unwinding device and control system for paper cores.

[0006] To achieve the above objectives, the present invention adopts the following technical solution: a side-pressure clamping type shaftless unwinding device and control system for paper cores, comprising bases on both sides and a PLC control terminal installed on one side of the bases, characterized in that: two guide rods are installed between the bases on both sides, and two symmetrical support arms are installed on the guide rods; a first transmission mechanism for clamping the paper core is installed inside each of the bases on both sides; a second transmission mechanism for driving the paper core to rotate is installed on one support arm; and a floating support mechanism for floating support of the paper core is installed on the other support arm; the floating support mechanism is provided with a tensioning block for tightening the inner wall of the paper core. The present invention is also equipped with an adaptive closed-loop control system, including a sensing and detection unit disposed in each tensioning block, a micro-displacement execution unit disposed for each tensioning block, and a data processing unit integrated in the PLC control terminal; The adaptive closed-loop control system is used to collect paper core inner wall shape data and single-point clamping pressure data in real time, complete the reconstruction of the complete inner wall shape of the paper core and the decoupling analysis of clamping pressure, and coordinate the adjustment of the micro-displacement execution unit, floating support mechanism and second transmission mechanism based on the analysis results, so as to realize the adaptive closed-loop control of uniform clamping force, no slippage and no paper core deformation during the paper core unwinding process.

[0007] Preferably, the first transmission mechanism includes a first geared motor installed in the base and a first lead screw rotatably installed inside the guide rod. The output ends of the first lead screw and the first geared motor are each equipped with a first toothed synchronous pulley. The outer sides of the two first toothed synchronous pulleys are meshed with a first synchronous belt. A guide strip for guiding the sliding of the support arm is installed on the periphery of the guide rod, and the bottom end of the support arm is threadedly connected to the first lead screw. The guide strip is arranged along the axial direction of the guide rod, and the bottom end of the support arm is provided with a guide groove adapted to the guide strip. The support arm slides with the guide strip through the guide groove.

[0008] Preferably, the second transmission mechanism includes a first bracket fixed to one side of the support arm and a first clamping roller rotatably mounted on the support arm. A first clamping plate is mounted on one end of the first clamping roller. A second reduction motor is mounted on the first bracket. The output end of the second reduction motor is connected to the first clamping plate through a coupling. The end face of the first clamping plate is provided with anti-slip texture.

[0009] Preferably, the floating support mechanism includes a second bracket installed on one side of the support arm, a second clamping roller installed inside the support arm, an inner frame located inside the second clamping roller and slidably connected to the support arm, an outer rotating shaft rotatably installed inside the inner frame, and an inner rotating shaft located inside the outer rotating shaft. One end of the inner rotating shaft is fixedly connected to a conical outer head, and four tensioning blocks are sleeved around the outer head. The other end of the inner rotating shaft is threadedly connected to a second lead screw. One end of the outer rotating shaft is equipped with a second clamping plate. A pressure sensor is installed on the support arm, located between the support arm and the second clamping plate. A displacement sensor is installed on the inner frame. A third reduction motor is installed on the second bracket. A second toothed synchronous pulley is installed on the output end of the third reduction motor and one end of the second lead screw. A second synchronous belt meshes with the outer sides of the two second toothed synchronous pulleys. A spline is installed around one end of the inner rotating shaft. A spline groove is opened at the junction of the inner frame and the inner rotating shaft. The inner rotating shaft is slidably connected to the inner frame through the spline and rotates synchronously in the circumferential direction.

[0010] Preferably, a first limiting plate is fixedly connected to the circumference of the inner rotating shaft, and a first return spring is installed between the first limiting plate and the inner frame. Two third limiting plates are fixedly connected to the circumference of the outer rotating shaft. A limiting groove that matches the third limiting plate is opened on the inner frame, and a second limiting plate is fixedly connected to the circumference of the inner frame. A second return spring is installed between the second clamping plate and the support arm. Rubber belts are connected between the plurality of tensioning blocks, and the plurality of tensioning blocks are slidably connected to one end of the second clamping plate. A plurality of T-shaped blocks are equidistantly installed on one end of the second clamping plate, and a T-shaped sliding groove that matches the T-shaped block is opened on the plurality of tensioning blocks. The tensioning blocks slide radially along the T-shaped sliding groove.

[0011] Preferably, the sensing and detection unit includes a miniature piezoelectric sensing unit and a miniature line scan vision unit; the miniature piezoelectric sensing unit is used to collect real-time pressure signals at the contact position between the tension block and the inner wall of the paper core, and the miniature line scan vision unit is used to collect local visual data of the inner wall of the paper core, including local contour and deformation signals.

[0012] Preferably, the data processing unit includes a trace fitting module, a pressure decoupling module, and a collaborative linkage module; the trace fitting module is used to stitch together multiple sets of line scan visual data to generate a complete trace model of the inner wall of the paper core; the pressure decoupling module is used to decompose the single-point pressure of each tensioning block and determine the clamping state; the collaborative linkage module is used to output control commands based on the trace model and the clamping state, and synchronously adjust the micro-displacement execution unit, the floating support mechanism, and the second transmission mechanism to complete adaptive closed-loop unwinding control.

[0013] Preferably, the pattern fitting module generates a complete pattern model of the inner wall of the paper core, specifically through data acquisition, preprocessing, coordinate calibration, splicing and fusion, surface fitting, and error correction steps: The miniature line-scan vision unit, located on the working surface of each tensioning block, synchronously collects multiple sets of raw line-scan vision data at a fixed frame rate during the unwinding and rotation of the paper core. A Gaussian filtering algorithm is used to remove noise and extract the set of feature points for the inner wall shape. Pixel coordinates are converted into physical coordinates using a coordinate transformation matrix, thus completing data scale normalization. A global cylindrical coordinate system for paper cores is constructed, and the spatial pose matrix of each micro-line scan vision unit is calibrated to achieve alignment between local data and the global coordinate system. The preprocessed local data of each group is mapped to the global cylindrical coordinate system to complete the seamless circumferential splicing and axial extension fusion, generating a three-dimensional point cloud dataset of the inner wall. The least squares surface fitting algorithm is used to fit the three-dimensional point cloud to reconstruct the initial trace model of the inner wall of the paper core. Combined with the clamping pressure to correct the radial deformation error of the model, the complete trace model of the inner wall of the paper core is obtained.

[0014] Preferably, the pressure decoupling module decomposes the single-point pressure and determines the clamping state, which is specifically achieved through pressure acquisition, signal decoupling, threshold discrimination, and state output steps: The pressure signals of each expansion block are collected in real time by a miniature piezoelectric sensing unit, resulting in four independent pressure sampling values. A moving average filtering algorithm is used to eliminate high-frequency vibration noise, complete baseline offset calibration, and obtain the calibrated effective pressure. Calculate the global clamping force, average pressure, pressure dispersion, and pressure deviation rate of individual blocks; Set normal clamping threshold, uniformity threshold, and deviation rate threshold, and determine the clamping state as normal clamping, local overpressure, false clamping / insufficient clamping, or uneven clamping according to the rules.

[0015] Preferably, the process by which the collaborative linkage module implements adaptive closed-loop unwinding control is as follows: It receives feedback data in real time from the pattern fitting module, pressure decoupling module, displacement sensor, pressure sensor and second transmission mechanism; Construct a global collaborative control objective function with the optimization goals of accurate compensation of the inner wall shape of the paper core, uniform and stable clamping pressure, dynamic adaptation of floating support, and constant output of unwinding torque; The control quantities of the micro-displacement actuator, the floating support mechanism, and the second transmission mechanism are calculated to obtain the radial micro-displacement compensation amount of each tensioning block, the axial floating adjustment amount of the floating support mechanism, and the unwinding drive torque of the second transmission mechanism. Control commands are synchronously sent to the corresponding actuators, and adaptive closed-loop unwinding control is completed by combining full closed-loop feedback correction.

[0016] Compared with the prior art, the beneficial effects of the present invention are: 1. This invention improves the paper core clamping fit by radially tightening the tensioning block in conjunction with the end faces of the first and second clamping plates; a sensing and detection unit is set up to collect clamping pressure data, the data processing unit coordinates to adjust the clamping state, and the floating support mechanism provides elastic support to eliminate unwinding slippage, ensure the accuracy and stability of the unwinding process, solve the technical defects of unstable clamping contact in existing devices, and maintain the stability of parameters in the unwinding process.

[0017] 2. The present invention achieves elastic floating support by incorporating a second reset spring in the floating support mechanism. The pressure sensor detects the clamping pressure in real time, and the adaptive closed-loop control system adjusts the clamping force to avoid rigid squeezing force, protect the integrity of the paper core structure at both ends, reduce the paper core breakage rate, and expand the paper core compatibility range of the device.

[0018] 3. This invention detects the displacement data of the inner frame by setting a displacement sensor, collects the shape data of the inner wall of the paper core by the sensing and detection unit, and completes the shape reconstruction and pressure decoupling analysis by the data processing unit. It coordinates the micro-displacement execution unit, floating support mechanism and second transmission mechanism to adapt to the diameter change during the unwinding process of the paper roll, realizes full-process adaptive closed-loop control, and improves the unwinding quality and accuracy.

[0019] In summary, this solution addresses the technical problems of slippage during clamping, easy compression and deformation of the paper core, and inability to adapt to changes in paper roll diameter in existing devices through the synergistic effect of mechanical structure improvement and adaptive closed-loop control system. It achieves stable clamping of the paper core, no compression damage, and simultaneous improvement in unwinding accuracy and quality, while expanding the paper core adaptability range and application scenarios of the device. Attached Figure Description

[0020] The accompanying drawings, which are included to provide a further understanding of the invention and form part of this application, illustrate exemplary embodiments of the invention and, together with their description, serve to explain the invention and do not constitute an undue limitation thereof. In the drawings: Figure 1 This is a schematic diagram of the overall appearance structure of the device proposed in this invention; Figure 2 This is a schematic diagram of the internal structure of the device proposed in this invention; Figure 3 This is a schematic diagram of the floating support mechanism proposed in this invention; Figure 4 This is a schematic diagram of the expansion block structure proposed in this invention; Figure 5 This is a schematic diagram of the inner frame structure proposed in this invention; Figure 6 This is a schematic diagram of the external rotating shaft structure proposed in this invention; Figure 7 This is a schematic diagram of the inner rotating shaft structure proposed in this invention; Figure 8 This is a schematic diagram of the second transmission mechanism proposed in this invention; Figure 9 This is a schematic cross-sectional view of the floating support mechanism proposed in this invention. Figure 10 This is a block diagram of the adaptive closed-loop control system proposed in this invention.

[0021] The components in the diagram are numbered as follows: 1. Base; 2. PLC control terminal; 3. Guide rod; 4. Support arm; 5. First geared motor; 6. First toothed synchronous pulley; 7. First synchronous belt; 8. First lead screw; 9. Second geared motor; 10. First clamping roller; 11. First clamping plate; 12. Third geared motor; 13. Second clamping roller; 14. Second clamping plate; 15. Tensioning block; 16. Inner rotating shaft; 17. First limiting plate; 18. Inner frame; 19. Second limiting plate; 20. Outer rotating shaft; 21. Third limiting plate; 22. First return spring; 23. Second return spring; 24. Second lead screw; 25. Second toothed synchronous pulley; 26. Second synchronous belt; 27. Pressure sensor; 28. Displacement sensor. Detailed Implementation

[0022] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments.

[0023] Example 1, refer to Figures 1 to 9 This invention discloses a side-pressure clamping type shaftless unwinding device and control system for paper cores, comprising two bases 1 on both sides and a PLC control terminal 2 installed on one side of the bases 1. The bases 1 facilitate the fixed support of the entire device, ensuring the stability of the device during operation and providing an installation benchmark for each component. The PLC control terminal 2 facilitates the receipt of feedback signals from various sensors and simultaneously controls the start, stop, and speed of each reduction motor, realizing automated control of the device and improving unwinding accuracy and efficiency. Two guide rods 3 are installed between the two bases 1, which facilitate the guidance and limiting of the support arm 4, ensuring the straightness of the support arm 4 during sliding and preventing deviation from affecting the paper core clamping accuracy. Two symmetrical support arms 4 are installed on the guide rods 3, which facilitate the installation of a second transmission mechanism and a... A floating support mechanism clamps and supports both ends of the paper core, ensuring uniform force distribution. A first transmission mechanism for clamping the paper core is installed within each of the two bases 1. This first transmission mechanism facilitates the sliding of the support arm 4 along the guide rod 3, adjusting the distance between the two support arms 4 to accommodate paper cores of different lengths, while simultaneously achieving initial clamping and positioning of the paper core. A second transmission mechanism for driving the paper core to rotate is installed on one support arm 4, facilitating uniform rotation of the paper core and enabling shaftless unwinding, ensuring stable unwinding speed. A floating support mechanism for floatingly supporting the paper core is installed on the other support arm 4, allowing for elastic floating clamping of the paper core, adapting to diameter changes during unwinding, and buffering vibrations during unwinding to prevent damage or slippage.

[0024] Reference Figures 1 to 3As shown, the first transmission mechanism includes a first geared motor 5 installed in the base 1 and a first lead screw 8 rotatably installed inside the guide rod 3. The first geared motor 5 provides a stable driving force to drive the first toothed synchronous pulley 6 to rotate. At the same time, the deceleration effect ensures that the sliding speed of the support arm 4 is smooth, avoiding excessive speed that could cause the paper core to shift. The first lead screw 8 converts the rotational motion of the first geared motor 5 into the linear motion of the support arm 4, enabling precise adjustment of the spacing between the support arms 4 and improving the positioning accuracy of the paper core clamping. The output ends of both the first lead screw 8 and the first geared motor 5 are equipped with first toothed synchronous pulleys 6, which facilitate cooperation between the two first toothed synchronous pulleys 6. The first synchronous belt 7 transmits power, ensuring that the power of the first geared motor 5 is stably transmitted to the first lead screw 8, avoiding power loss or transmission deviation; the two first toothed synchronous pulleys 6 are meshed with the first synchronous belt 7 on their outer sides, which facilitates the synchronous rotation of the first geared motor 5 and the first lead screw 8, ensuring the smoothness and synchronicity of the transmission and avoiding jamming; the guide rod 3 is equipped with a guide strip on its periphery to guide the sliding of the support arm 4, which facilitates the limiting of the sliding direction of the support arm 4, preventing the support arm 4 from rotating or deviating when sliding, and ensuring that the support arm 4 slides smoothly along the axial direction of the guide rod 3; and the bottom end of the support arm 4 is threadedly connected to the first lead screw 8.

[0025] Reference Figure 3 As shown, the second transmission mechanism includes a first bracket fixed to one side of the support arm 4 and a first clamping roller 10 rotatably mounted on the support arm 4. The first clamping roller 10 facilitates clamping one end of the paper core in conjunction with the first clamping plate 11, while also assisting the paper core in rotation, reducing friction during rotation, and preventing paper core wear. The first clamping plate 11 is mounted on one end of the first clamping roller 10, which facilitates direct contact with the end face of the paper core, increasing the contact area and improving clamping stability. A second reduction motor 9 is mounted on the first bracket, which provides driving force to drive the first clamping plate 11 and the first clamping roller 10 to rotate, thereby driving the paper core to unwind at a uniform speed. At the same time, the reduction action ensures that the unwinding speed is stable and controllable. The output end of the second reduction motor 9 is connected to the first clamping plate 11 through a coupling.

[0026] Reference Figure 5 , Figure 7 , Figure 9As shown, the floating support mechanism includes a second bracket installed on one side of the support arm 4, a second clamping roller 13 installed inside the support arm 4, an inner frame 18 located inside the second clamping roller 13 and slidably connected to the support arm 4, an outer rotating shaft 20 rotatably installed inside the inner frame 18, and an inner rotating shaft 16 located inside the outer rotating shaft 20. The second clamping roller 13 facilitates the floating clamping of the other end of the paper core in conjunction with the second clamping plate 14, assisting the rotation of the paper core, reducing wear during paper core rotation, and adapting to the floating displacement of the paper core. The inner frame 18 facilitates the installation of the outer rotating shaft 20 and the inner rotating shaft 16, and can slide along the support arm 4 to achieve the floating support function and buffer the paper core. The vibration and displacement changes during core unwinding; the outer rotating shaft 20 facilitates the synchronous rotation of the second clamping plate 14 and the paper core, while providing installation space for the inner rotating shaft 16, ensuring the axial sliding and circumferential rotation of the inner rotating shaft 16; the inner rotating shaft 16 facilitates the movement of the conical outer mandrel, realizing the radial expansion and reset of the tensioning block 15, thereby achieving the expansion and clamping of the paper core; one end of the inner rotating shaft 16 is fixedly connected to the conical outer mandrel, which facilitates the compression of the tensioning block 15 during axial movement, causing the tensioning block 15 to expand radially, achieving expansion and clamping of the inner wall of the paper core, adapting to paper cores of different inner diameters; four tensioning blocks 15 are sleeved around the outer mandrel. Four tensioning blocks 15 ensure even contact with the inner wall of the paper core, achieving uniform tension and preventing damage due to excessive localized force, while also improving clamping stability. The other end of the inner rotating shaft 16 is threadedly connected to a second lead screw 24, which converts the rotational motion of the third reduction motor 12 into axial linear motion of the inner rotating shaft 16, enabling precise movement of the outer mandrel and thus controlling the tension of the tensioning blocks 15. A second clamping plate 14 is mounted on one end of the outer rotating shaft 20, which works in conjunction with the first clamping plate 11 to clamp both ends of the paper core and provides mounting support for the tensioning blocks 15, ensuring proper tension. The sliding stability of block 15; a pressure sensor 27 is installed on the support arm 4, which facilitates real-time detection of the pressure between the second clamping plate 14 and the support arm 4, and provides feedback on the clamping force of the paper core, so that the PLC control terminal 2 can adjust the clamping pressure to avoid excessive pressure damaging the paper core or insufficient pressure causing the paper core to slip; the pressure sensor 27 is located between the support arm 4 and the second clamping plate 14, and a displacement sensor 28 is installed on the inner frame 18, which facilitates real-time detection of the sliding displacement of the inner frame 18, and provides feedback on the position change of the paper core during the unwinding process, so that the PLC control terminal 2 can adjust in time to ensure unwinding accuracy.

[0027] Reference Figures 6 to 9As shown, a third geared motor 12 is mounted on the second bracket. The third geared motor 12 provides stable driving force, rotating the second toothed synchronous pulley 25, which in turn drives the second lead screw 24 to rotate, achieving axial movement of the inner shaft 16. Simultaneously, the reduction speed ensures smooth movement of the inner shaft 16 and precise control of the tensioning block 15. Second toothed synchronous pulleys 25 are mounted on the output end of the third geared motor 12 and one end of the second lead screw 24. These two toothed synchronous pulleys 25 work in conjunction with the second synchronous belt 26 to transmit power, ensuring stable power transmission from the third geared motor 12 to the second lead screw 24 and preventing power loss or transmission misalignment. The outer sides of the two toothed synchronous pulleys 25 are engaged with a second synchronous belt 26. The step belt 26 facilitates the synchronous rotation of the third reduction motor 12 and the second lead screw 24, ensuring smooth and synchronous transmission, preventing jamming, and ensuring precise movement of the inner rotating shaft 16. A spline is installed on the circumference of one end of the inner rotating shaft 16, allowing for synchronous circumferential rotation between the inner rotating shaft 16 and the inner frame 18, while also allowing the inner rotating shaft 16 to slide axially along the inner frame 18. This ensures that the inner rotating shaft 16 can both drive the outer top head to move and rotate synchronously with the inner frame 18. A spline groove is provided at the junction of the inner frame 18 and the inner rotating shaft 16, allowing the inner rotating shaft 16 to slide and rotate synchronously circumferentially with the inner frame 18 via the spline. A first limiting plate 17 is fixedly connected to the circumference of the inner rotating shaft 16, facilitating the movement of the third reduction motor 12 and the second lead screw 24. A return spring 22 is used for limiting and preventing the first return spring 22 from falling off. It also transmits the elastic force of the spring, driving the inner rotating shaft 16 to reset. A first return spring 22 is installed between the first limiting plate 17 and the inner frame 18. The first return spring 22 facilitates the reverse movement of the inner rotating shaft 16 when the force on it stops, causing the tensioning block 15 to retract and reset, facilitating the disassembly and replacement of the paper core. Two third limiting plates 21 are fixedly connected to the circumference of the outer rotating shaft 20. These three limiting plates 21 axially limit the outer rotating shaft 20, preventing axial movement within the inner frame 18 and ensuring the stability of its rotation. The inner frame 18 has limiting grooves that cooperate with the third limiting plates 21, allowing for axial movement. The groove facilitates the accommodation of the third limiting plate 21 and guides and limits the third limiting plate 21, ensuring that the outer rotating shaft 20 rotates smoothly within the inner frame 18 and avoids deviation; and the second limiting plate 19 is fixedly connected to the periphery of the inner frame 18, which facilitates the limiting of the second return spring 23, preventing the second return spring 23 from falling off, and at the same time transmits the elastic force of the spring to realize the floating return of the inner frame 18; the second return spring 23 is installed between the second clamping plate 14 and the support arm 4, and rubber belts are connected between the multiple tensioning blocks 15. The rubber belts facilitate the limitation of the expansion range of the tensioning blocks 15, and at the same time drive them to return synchronously when the tensioning blocks 15 contract, ensuring the synchronicity of the tensioning blocks 15 and avoiding jamming of a single tensioning block 15;Furthermore, multiple tensioning blocks 15 are slidably connected to one end of the second clamping plate 14. Multiple T-shaped blocks are equidistantly installed on one end of the second clamping plate 14. Each tensioning block 15 has a T-shaped groove adapted to the T-shaped block. The tensioning block 15 slides radially along the T-shaped groove. This sliding method facilitates the radial expansion of the tensioning block 15 under the pressure of the conical outer head, achieving tensioning and clamping of the paper core. Simultaneously, it contracts radially under the action of the return spring, facilitating paper core loading and unloading. The guide strip is axially arranged along the guide rod 3. The bottom end of the support arm 4 has a guide groove adapted to the guide strip. The support arm 4 slides with the guide strip through the guide groove. The end face of the first clamping plate 11 has anti-slip textures. These textures increase the friction between the first clamping plate 11 and the end face of the paper core, preventing relative slippage between the paper core and the first clamping plate 11 during unwinding, ensuring stable unwinding speed, and improving unwinding accuracy.

[0028] Example 2 is basically the same as the technical solution in Example 1, except that, referring to... Figure 10 As shown, the present invention is also equipped with an adaptive closed-loop control system, which includes a sensing and detection unit disposed in each tensioning block 15, a micro-displacement execution unit disposed in each tensioning block 15, and a data processing unit integrated in the PLC control terminal 2. The sensing and detection unit is used to collect local shape data and single-point clamping pressure data of the inner wall of the paper core in real time; the sensor detection unit includes a miniature piezoelectric sensing unit and a miniature line scan vision unit; the miniature piezoelectric sensing unit is used to collect real-time pressure signals at the contact position between the tension block 15 and the inner wall of the paper core, and the miniature line scan vision unit is used to collect local visual data of the inner wall of the paper core, including local contour and deformation signals; the local visual data collected by the miniature line scan vision unit on each tension block 15 is recorded as multiple sets of line scan visual data; The micro-displacement actuator is used to drive the corresponding tensioning block 15 to perform independent radial micro-displacement adjustment; The data processing unit includes a pattern fitting module, a pressure decoupling module, and a collaborative linkage module; The trace fitting module is used to stitch together multiple sets of line scan visual data to generate a complete trace model of the inner wall of the paper core. The pressure decoupling module is used to decompose the single-point pressure of each tensioning block 15 and determine the clamping state. The collaborative linkage module is used to output control commands based on the trace model and clamping state, and synchronously adjust the micro-displacement execution unit, floating support mechanism and second transmission mechanism to complete adaptive closed-loop unwinding control.

[0029] Specifically, the trace fitting module is used to stitch together multiple sets of line scan visual data to generate a complete trace model of the inner wall of the paper core. This is achieved through six steps: data acquisition, preprocessing, coordinate calibration, stitching and fusion, surface fitting, and error correction, as detailed below: Miniature line-scan vision units, each located on the clamping working surface of each tensioning block 15, synchronously acquire multiple sets of raw line-scan vision data at a fixed frame rate during the unwinding and rotation of the paper core. ,in The data represents pixel plane coordinates, and the four sets of data correspond to the acquisition areas of the four expansion blocks 15. A Gaussian filtering algorithm is used to remove dust, light, and sensor noise. The filtering formula is as follows: In the formula: The width of the filter kernel. These are pixel coordinates; After filtering, the inner wall edge points, radial extreme points, and circumferential curvature points are extracted to form a set of trace feature points. , The number of feature points in a single set of data; Then the pixel coordinates Through coordinate transformation matrix Convert to physical coordinates using the following formula: In the formula: To obtain the physical three-dimensional coordinates of the inner wall of the paper core, data scale normalization was completed; With the central axis of the paper core as Axial and radial directions are Axial and circumferential directions are Axis, constructing a global cylindrical coordinate system for the paper core ; Combined with the axial displacement of the inner frame fed back by displacement sensor 28 Radial extension of the expansion block The spatial pose matrix of each micro-line scan vision unit is calibrated. This achieves alignment between local data and the global coordinate system; The preprocessed local data from each group are processed through the pose matrix. Mapped to a global cylindrical coordinate system, a neighborhood feature matching algorithm is used to achieve seamless circumferential stitching. The objective function for the matching error is: In the formula: For matching feature points between two adjacent sets of data, minimize the error. Achieve precise alignment; then extend and fuse along the paper core axis to generate a 3D point cloud dataset of the inner wall covering the entire clamping range. ; The least squares surface fitting algorithm is used to process the 3D point cloud. By fitting and reconstructing the initial trace model of the inner wall of the paper core, the fitting equation is: In the formula: The radial distance of the inner wall. For circumferential angle, This refers to the axial position. These are the fitting coefficients; Single-point clamping pressure combining pressure sensor 27 and miniature piezoelectric sensing unit Correcting the radial deformation error of the model ,in The pressure-deformation coupling coefficient is used to obtain a complete trace model of the inner wall of the paper core, which characterizes the overall contour, ellipticity, local concavity and convexity, and radial deformation of the inner wall.

[0030] Specifically, the pressure decoupling module is used to decompose the single-point pressure of each tensioning block 15 and determine the clamping state. This is achieved through four steps: pressure acquisition, signal decoupling, threshold discrimination, and status output, as detailed below: Synchronous acquisition of single-point clamping pressure: Miniature piezoelectric sensing units embedded in the clamping working surfaces of each tensioning block 15 acquire single-point pressure signals at the contact positions between the corresponding tensioning block 15 and the inner wall of the paper core in real time, obtaining four independent pressure sampling values. subscript These correspond to the numbers of the expansion blocks 15; Signal preprocessing and baseline calibration: A moving average filtering algorithm is used to eliminate high-frequency vibration noise. The filtering formula is as follows: In the formula: For the first Pressure value after filtering of 15 expansion blocks The length of the sliding window. For the first 15th expansion block Secondary initial sampling pressure; Next, perform baseline offset calibration. The calibration formula is: In the formula: For the effective pressure after calibration, For the first Each expansion joint has a no-load reference pressure of 15. Multi-dimensional pressure decoupling calculation, including global clamping force calculation, pressure mean calculation, pressure dispersion calculation, and single-block pressure deviation rate; among which: Global clamping force calculation formula In the formula: Total clamping pressure of the four-way expansion blocks 15; formula for calculating the average pressure. In the formula: The average clamping pressure; formula for calculating pressure dispersion. In the formula: Pressure distribution dispersion, used to characterize clamping uniformity; formula for calculating single-block pressure deviation rate. In the formula: For the first The relative deviation rate of pressure for each expansion block is 15. Clamping state classification: Set normal clamping threshold Uniformity threshold Deviation rate threshold The following rules apply: like and and This was determined to be a normal clamping action; like or any This was determined to be a localized overpressure. like or any This is determined to be a false grip / insufficient grip; like but or any This is determined to be uneven clamping; Decoupling result output: The pressure decoupling module decouples the 15 independent effective pressures of each expansion block. Total pressure Mean pressure Dispersion The final clamping state is synchronously transmitted to the collaborative linkage module, serving as the basis for the coordinated adjustment of the micro-displacement execution unit, the floating support mechanism, and the second transmission mechanism.

[0031] Specifically, the collaborative linkage module outputs control commands based on the complete trace model of the inner wall of the paper core and the clamping state, and synchronously adjusts the micro-displacement execution unit, the floating support mechanism, and the second transmission mechanism to achieve adaptive closed-loop unwinding control, as detailed below: The collaborative linkage module receives in real time the complete trace model data of the inner wall of the paper core output by the trace fitting module, the single-point clamping pressure and clamping status data of each tensioning block 15 output by the pressure decoupling module, the axial displacement data of the inner frame output by the displacement sensor 28, the overall clamping pressure data output by the pressure sensor 27, and the real-time rotation speed data of the second transmission mechanism. With the optimization objectives of accurate compensation for the inner wall shape of the paper core, uniform and stable clamping pressure, dynamic adaptation of floating support, and constant output of unwinding torque, a global collaborative control objective function is constructed, the expression of which is: In the formula: The cost function for global collaborative control; Preset weighting coefficients; For the first Each expansion block 15 corresponds to the radial trace deviation of the inner wall of the paper core; For the first Each expansion joint provides 15 radial micro-displacement compensation. For the first The effective clamping pressure after calibration of each expansion block 15; The average clamping pressure of the four expansion blocks is 15. This refers to the axial floating adjustment amount of the floating support mechanism; The paper core eccentricity coupling coefficient; This refers to the axial position of the paper core. The second transmission mechanism outputs torque in real time. This is the system's rated unwinding torque; Next, the control quantities of the branch actuators are calculated, including the control quantities of the micro-displacement actuator, the floating support mechanism, and the second transmission mechanism. Specifically, the micro-displacement actuator control quantity calculation is based on the radial trace deviation of the inner wall of the paper core and the single-point clamping pressure deviation, calculating the independent radial micro-displacement compensation of each tensioning block 15. The calculation formula is as follows: In the formula: This is the pressure-displacement coupling coefficient; The control quantity of the floating support mechanism is specifically calculated based on the paper core rotational eccentricity and the overall clamping pressure deviation, to calculate the axial floating adjustment amount. The calculation formula is as follows: In the formula, The eccentric-floating coupling coefficient; This refers to the real-time eccentricity of the paper core rotation. The pressure-float coupling coefficient; The overall clamping pressure detected by pressure sensor 27; The system presets the clamping pressure; the control quantity of the second transmission mechanism is specifically calculated based on the clamping pressure dispersion and the maximum radial trace deviation, to calculate the unwinding drive torque. The calculation formula is as follows: In the formula, The pressure dispersion-torque coupling coefficient; The clamping pressure dispersion; The trace deviation-torque coupling coefficient; This represents the maximum radial trace deviation of the inner wall of the paper core. Synchronous control command output execution: The collaborative linkage module converts the calculated radial micro-displacement compensation amount, axial floating adjustment amount, and unwinding drive torque into standard control commands and synchronously sends them to the corresponding actuators; drives the micro-displacement actuator to complete the independent radial micro-displacement adjustment of each tensioning block 15, drives the third reduction motor of the floating support mechanism to adjust the axial floating amount of the inner frame, and drives the second reduction motor 9 of the second transmission mechanism to adjust the torque output. Full closed-loop feedback correction: The micro line scan vision unit, micro piezoelectric sensing unit, displacement sensor 28, and pressure sensor 27 collect the adjusted feedback data in real time and feed it back to the collaborative linkage module; the collaborative linkage module iteratively executes the data receiving, target calculation, and command output steps according to a fixed control cycle, continuously correcting the control parameters to form a full closed-loop adaptive control of trace-pressure-displacement-torque until the paper core clamping state is stable and there is no slippage or drift during unwinding, thus completing the adaptive closed-loop unwinding control.

[0032] Working principle: After the device is started, the first transmission mechanism in the base 1 on both sides runs, the first geared motor 5 drives the first toothed synchronous wheel 6 to rotate, and drives the first lead screw 8 to rotate via the first synchronous belt 7. The support arm 4 moves axially along the guide rod 3, and the two support arms 4 move towards each other to complete the initial clamping of the paper core; the second clamping plate 14 presses against the pressure sensor 27, and the pressure sensor 27 transmits the pressure signal to the PLC control terminal 2. The PLC control terminal 2 controls the first transmission mechanism to stop running.

[0033] The PLC control terminal 2 starts the floating support mechanism. The third reduction motor 12 drives the second toothed synchronous wheel 25 to rotate, which in turn drives the second lead screw 24 to rotate via the second synchronous belt 26. The inner rotating shaft 16 moves axially along the inner frame 18, and the conical outer top head squeezes the expansion block 15. The expansion block 15 expands radially along the T-shaped groove of the second clamping plate 14, and the expansion block 15 fits against the inner wall of the paper core to complete the fixation.

[0034] The PLC control terminal 2 starts the second transmission mechanism, and the second geared motor 9 drives the first clamping plate 11 to rotate. The first clamping plate 11 drives the paper core to rotate, and the first clamping roller 10 and the second clamping roller 13 rotate synchronously with the paper core. The pressure sensor 27 and the displacement sensor 28 collect pressure and displacement signals in real time and transmit them to the PLC control terminal 2. The PLC control terminal 2 adjusts the speed of each geared motor according to the signals.

[0035] During unwinding, the second reset spring 23 provides elastic support for the inner frame 18 and the second clamping plate 14, buffering the vibration and displacement of the paper core rotation; after unwinding is completed, the first reset spring 22 drives the inner rotating shaft 16 to reset, the tensioning block 15 contracts, and the paper core is disassembled.

[0036] When the adaptive closed-loop control system is running, the sensing and detection unit collects the paper core inner wall shape data and single-point clamping pressure data, and transmits them to the data processing unit integrated in the PLC control terminal 2; the data processing unit completes the paper core inner wall shape reconstruction and clamping pressure decoupling analysis, outputs control commands, and coordinates the micro-displacement execution unit, floating support mechanism and second transmission mechanism to realize the paper core shaftless unwinding adaptive closed-loop control.

[0037] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. A side-pressure clamping type shaftless unwinding device for paper cores, comprising bases (1) on both sides and a PLC control terminal (2) installed on one side of the bases (1), characterized in that: Two guide rods (3) are installed between the two bases (1). Two symmetrical support arms (4) are installed on the guide rods (3). A first transmission mechanism for clamping the paper core is installed in the bases (1) on both sides. A second transmission mechanism for driving the paper core to rotate is installed on one support arm (4). A floating support mechanism for floating support of the paper core is installed on the other support arm (4). An expansion block (15) for expanding the inner wall of the paper core is provided inside the floating support mechanism. It is also equipped with an adaptive closed-loop control system, including a sensing and detection unit located in each tension block (15), a micro-displacement execution unit set for each tension block (15), and a data processing unit integrated into the PLC control terminal (2); The adaptive closed-loop control system is used to collect paper core inner wall trace data and single-point clamping pressure data in real time, complete the reconstruction of the complete paper core inner wall trace and the decoupling analysis of clamping pressure, and coordinate the adjustment of micro-displacement execution unit, floating support mechanism and second transmission mechanism based on the analysis results to achieve adaptive closed-loop control with uniform clamping force, no slippage and no paper core deformation during the paper core unwinding process. The floating support mechanism includes a second bracket installed on one side of the support arm (4), a second clamping roller (13) installed inside the support arm (4), an inner frame (18) located inside the second clamping roller (13) and slidably connected to the support arm (4), an outer rotating shaft (20) rotatably installed inside the inner frame (18), and an inner rotating shaft (16) located inside the outer rotating shaft (20). One end of the inner rotating shaft (16) is fixedly connected to a conical outer top head, and four expansion blocks (15) are sleeved around the outer top head. The other end of the inner rotating shaft (16) is threadedly connected to a second lead screw (24). One end of the outer rotating shaft (20) is equipped with a second clamping plate (14). A pressure sensor (2) is installed on the support arm (4). 7), the pressure sensor (27) is located between the support arm (4) and the second clamp (14), and the displacement sensor (28) is installed on the inner frame (18); the third geared motor (12) is installed on the second bracket, and the output end of the third geared motor (12) and the second lead screw (24) are both equipped with second toothed synchronous pulleys (25), and the two second toothed synchronous pulleys (25) are meshed with a second synchronous belt (26) on their outer sides. A spline is installed on the periphery of one end of the inner rotating shaft (16), and a spline groove is opened at the junction of the inner frame (18) and the inner rotating shaft (16). The inner rotating shaft (16) is slidably connected to the inner frame (18) through the spline and rotates synchronously in the circumferential direction. The inner rotating shaft (16) is fixedly connected to a first limiting plate (17) on its periphery. A first return spring (22) is installed between the first limiting plate (17) and the inner frame (18). The outer rotating shaft (20) is fixedly connected to two third limiting plates (21) on its periphery. The inner frame (18) is provided with a limiting groove that matches the third limiting plate (21). The inner frame (18) is fixedly connected to a second limiting plate (19) on its periphery. A second return spring (23) is installed between the second clamping plate (14) and the support arm (4). Rubber belts are connected between the multiple tensioning blocks (15). The multiple tensioning blocks (15) are slidably connected to one end of the second clamping plate (14). Multiple T-shaped blocks are equidistantly installed at one end of the second clamping plate (14). T-shaped grooves that match the T-shaped blocks are provided on the multiple tensioning blocks (15). The tensioning blocks (15) slide radially along the T-shaped grooves.

2. The side-pressure clamping type shaftless unwinding device for paper cores according to claim 1, characterized in that: The first transmission mechanism includes a first geared motor (5) installed in the base (1) and a first lead screw (8) rotatably installed inside the guide rod (3). The output ends of the first lead screw (8) and the first geared motor (5) are both equipped with first toothed synchronous pulleys (6). The two first toothed synchronous pulleys (6) are meshed with a first synchronous belt (7) on their outer sides. The guide rod (3) is equipped with a guide bar for guiding the sliding of the support arm (4), and the bottom end of the support arm (4) is threadedly connected to the first lead screw (8). The guide bar is arranged along the axial direction of the guide rod (3), and the bottom end of the support arm (4) is provided with a guide groove that matches the guide bar. The support arm (4) slides with the guide bar through the guide groove.

3. The side-pressure tightening type shaftless unwinding device for paper cores according to claim 1, characterized in that: The second transmission mechanism includes a first bracket fixed to one side of the support arm (4) and a first clamping roller (10) rotatably mounted on the support arm (4). A first clamping plate (11) is mounted on one end of the first clamping roller (10). A second reduction motor (9) is mounted on the first bracket. The output end of the second reduction motor (9) is connected to the first clamping plate (11) through a coupling. The end face of the first clamping plate (11) is provided with anti-slip texture.

4. The side-pressure tightening type shaftless unwinding device for paper cores according to claim 1, characterized in that: The sensing and detection unit includes a miniature piezoelectric sensing unit and a miniature line scan vision unit; the miniature piezoelectric sensing unit is used to collect real-time pressure signals at the contact position between the tension block (15) and the inner wall of the paper core, and the miniature line scan vision unit is used to collect local visual data of the inner wall of the paper core, including local contour and deformation signals.

5. The side-pressure clamping type shaftless unwinding device for paper cores according to claim 1, characterized in that: The data processing unit includes a trace fitting module, a pressure decoupling module, and a collaborative linkage module. The trace fitting module is used to stitch together multiple sets of line scan visual data to generate a complete trace model of the inner wall of the paper core. The pressure decoupling module is used to decompose the single-point pressure of each tensioning block (15) and determine the clamping state. The collaborative linkage module is used to output control commands based on the trace model and the clamping state, and synchronously adjust the micro-displacement execution unit, the floating support mechanism, and the second transmission mechanism to complete the adaptive closed-loop unwinding control.

6. The side-pressure clamping type shaftless unwinding device for paper cores according to claim 5, characterized in that: The shape fitting module generates a complete shape model of the inner wall of the paper core, which is achieved through data acquisition, preprocessing, coordinate calibration, splicing and fusion, surface fitting, and error correction steps. The miniature line scanning vision unit, which is located on the working surface of each tensioning block (15), synchronously collects multiple sets of line scanning vision raw data at a fixed frame rate during the unwinding and rotation of the paper core. A Gaussian filtering algorithm is used to remove noise and extract the set of feature points for the inner wall shape. Pixel coordinates are converted into physical coordinates using a coordinate transformation matrix, thus completing data scale normalization. A global cylindrical coordinate system for paper cores is constructed, and the spatial pose matrix of each micro-line scan vision unit is calibrated to achieve alignment between local data and the global coordinate system. The preprocessed local data of each group is mapped to the global cylindrical coordinate system to complete the seamless circumferential splicing and axial extension fusion, generating a three-dimensional point cloud dataset of the inner wall. The least squares surface fitting algorithm is used to fit the three-dimensional point cloud to reconstruct the initial trace model of the inner wall of the paper core. Combined with the clamping pressure to correct the radial deformation error of the model, the complete trace model of the inner wall of the paper core is obtained.

7. A side-pressure clamping type shaftless unwinding device for paper cores according to claim 5, characterized in that: The pressure decoupling module decomposes single-point pressure and determines the clamping state, specifically through pressure acquisition, signal decoupling, threshold discrimination, and state output steps: The single-point pressure signal of each expansion block (15) is collected in real time by the micro piezoelectric sensing unit to obtain four independent pressure sampling values; A moving average filtering algorithm is used to eliminate high-frequency vibration noise, complete baseline offset calibration, and obtain the calibrated effective pressure. Calculate the global clamping force, average pressure, pressure dispersion, and pressure deviation rate of individual blocks; Set normal clamping threshold, uniformity threshold, and deviation rate threshold, and determine the clamping state as normal clamping, local overpressure, false clamping / insufficient clamping, or uneven clamping according to the rules.

8. The side-pressure clamping type shaftless unwinding device for paper cores according to claim 5, characterized in that: The process by which the collaborative linkage module achieves adaptive closed-loop unwinding control is as follows: Real-time reception of feedback data from the pattern fitting module, pressure decoupling module, displacement sensor (28), pressure sensor (27) and second transmission mechanism; Construct a global collaborative control objective function with the optimization goals of accurate compensation of the inner wall shape of the paper core, uniform and stable clamping pressure, dynamic adaptation of floating support, and constant output of unwinding torque; The control quantities of the micro-displacement actuator, the floating support mechanism and the second transmission mechanism are calculated to obtain the radial micro-displacement compensation of each tensioning block (15), the axial floating adjustment of the floating support mechanism and the unwinding drive torque of the second transmission mechanism. Control commands are synchronously sent to the corresponding actuators, and adaptive closed-loop unwinding control is completed by combining full closed-loop feedback correction.

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