Device and method for improving folding of output paper sheet of sizing machine

Abstract

The invention provides a device and method for improving folding of output paper sheets of a sizing machine, and relates to the technical field of paper processing equipment. The device comprises a mounting seat, a control box, a transverse position adjusting mechanism, an angle adjusting mechanism, an airflow injection mechanism and a control system. The transverse position adjusting mechanism drives a threaded connecting rod to rotate through a motor to adjust the transverse position of the nozzle; the angle adjusting mechanism pushes a movable block to move through an electric telescopic rod, so that an adjusting plate rotates to adjust the inclination angle of the nozzle; the airflow jetting mechanism comprises a connecting pipe and a plurality of nozzles, and jets airflow to the paper sheets to stretch the paper sheets; and the control system adjusts each parameter in real time and monitors the operation state. The method comprises the steps that the device is fixedly installed on a sizing machine, the transverse position of the nozzle is adjusted according to the transverse width of a paper sheet, the inclination angle of the nozzle is adjusted according to the fluctuation of the surface of the paper sheet, airflow is jetted to the paper sheet through the nozzle, and the running state of the device is monitored in real time. The paper sheet stretching device can adapt to different paper types, and the paper sheet stretching quality and efficiency are improved.

Description

Technical Field

[0001] The present invention relates to the technical field of paper processing equipment, and particularly relates to a device and method for improving the folding of paper sheets discharged from a sizing machine. Background Art

[0002] With the development of intelligent manufacturing and flexible processing technologies, the stability and consistency of paper sheet forming quality have become key indicators in the control system of paper product production lines, which have a direct impact on the surface cleanliness of paper, the finished product rate, and subsequent printing adaptability. Therefore, higher requirements are put forward for solving the problem of paper folding.

[0003] In the existing traditional technologies, the problem of paper folding is usually alleviated by fixed-angle air jet devices, mechanical pressure wheels, guide rollers, or swing-type tensioning devices. These devices rely on preset parameters and static structures to apply external forces to unfold the paper. However, due to their fixed structures, lagging responses, and low adjustment accuracy, it is difficult to adapt to the complex dynamic deformation characteristics exhibited by different types of paper during high-speed operation. Some solutions introduce manual observation and manual adjustment, but this method has problems such as cumbersome operation, lagging response, poor consistency, and high labor costs, especially showing obvious limitations under the conditions of large-format, high-speed, and multi-specification continuous production.

[0004] There are also many technical defects in the existing technologies during the process of paper folding treatment, such as single adjustment dimension, lack of real-time update mechanism for control parameters, poor stability of the shaping force field, low equipment versatility, and weak fault diagnosis and recovery capabilities. These problems make it difficult for the sizing machine to achieve adaptive and precise control when processing papers of different materials, thicknesses, and transverse widths, thus affecting the finished product rate and quality stability.

[0005] In addition, the existing fixed-structure air jet device cannot adjust the nozzle position and angle in real time according to the dynamic changes of the paper during high-speed operation, resulting in a mismatch between the air flow action area and the area of the paper sheet that actually needs to be unfolded, reducing the effectiveness of air flow unfolding. At the same time, the fixed setting of the air source pressure is also difficult to meet the different air flow intensity requirements of different papers, easily leading to problems such as excessive air flow damaging the paper surface or insufficient air flow having poor effects. Summary of the Invention

[0006] The purpose of the present invention is to provide a device and method for improving the folding of paper sheets discharged from a sizing machine, and a new paper sheet shaping system integrating structural optimization, intelligent parameter regulation, and state feedback diagnosis is constructed to improve the process efficiency and forming quality, so as to meet the requirements of modern paper product production for high quality, high efficiency, and high consistency.

[0007] To achieve the above purpose, the present invention is realized through the following technical solutions:

[0008] A device for improving the folding of paper sheets discharged from a sizing machine includes

[0009] Mounting base, for fixedly mounting on a sizing machine;

[0010] Control box, fixedly mounted on the top of the mounting base;

[0011] Horizontal position adjusting mechanism, arranged on the outer wall of the control box, for adjusting the horizontal position of the nozzle;

[0012] Angle adjusting mechanism, connected to the horizontal position adjusting mechanism, for adjusting the tilt angle of the nozzle;

[0013] Airflow jetting mechanism, including a connecting pipe connected to the horizontal position adjusting mechanism and the angle adjusting mechanism and a plurality of nozzles arranged on the outer wall of the connecting pipe, for jetting airflow onto the paper sheet;

[0014] Control system, arranged in the control box, for controlling the operation of the horizontal position adjusting mechanism, the angle adjusting mechanism and the airflow jetting mechanism.

[0015] Furthermore: The horizontal position adjusting mechanism includes:

[0016] Fixed frame, fixedly mounted on the outer wall of the control box;

[0017] Threaded connecting rod, movably mounted inside the fixed frame, driven to rotate by a motor;

[0018] Extension plate, movably mounted on the outer wall of the fixed frame;

[0019] Threaded connection ring, fixedly mounted on the outer wall of the extension plate, threadedly connected to the threaded connecting rod.

[0020] Furthermore: The angle adjusting mechanism includes:

[0021] Connecting plate, fixedly mounted on the bottom of the extension plate, with a chute opened at the top;

[0022] Electric telescopic rod, fixedly mounted inside the chute;

[0023] Moving block, movably mounted inside the chute, fixedly connected to the output shaft of the electric telescopic rod; Adjusting plate, movably mounted on the top of the moving block through a hinge;

[0024] Bottom block, fixedly mounted on the bottom of the connecting pipe, hinged to the adjusting plate through a hinge.

[0025] Furthermore: The connecting pipe of the airflow jetting mechanism is an arc-shaped hollow structure, movably connected to the extension plate through a hinge, and is connected to the control box through an elastic hose.

[0026] Further: The control system includes:

[0027] An air source module for outputting gas with adjustable pressure;

[0028] A drive control module for controlling the lateral position adjustment mechanism and the angle adjustment mechanism;

[0029] A parameter adaptation module for calculating the optimal nozzle position, angle and gas pressure according to the paper properties; a fault diagnosis module for monitoring the operating states of various components and performing fault diagnosis.

[0030] Further: An installation opening is formed in the outer wall of the control box, and a transparent window is fixedly installed inside the installation opening for observing the operating state inside the control box.

[0031] The present invention also provides a method for improving the paper folding of the paper output by a sizing machine using the above device, which is characterized by including the following steps:

[0032] S1: Fixingly install the device on the sizing machine;

[0033] S2: Adjust the lateral position of the nozzle according to the lateral width of the paper;

[0034] S3: Adjust the tilt angle of the nozzle according to the undulation of the paper surface;

[0035] S4: Jet an air flow with a pressure of 4-6 kg onto the paper through the nozzle, so that the paper is stretched from the middle to both sides under the action of the air flow to eliminate folding;

[0036] S5: Real-time monitor the operating state of the device, and perform maintenance operations when abnormalities are found

[0037] Further: In step S2, the threaded connecting rod is rotated by a motor, and the threaded connecting rod is in threaded cooperation with the threaded connection ring on the extension plate. As the threaded connecting rod rotates, the extension plate makes a horizontal displacement adjustment along the outer wall of the fixed frame, thereby changing the lateral position of the nozzle.

[0038] Further: In step S3, the electric telescopic rod is used to push the movable block to move in the chute on the top of the connecting plate. Since the adjusting plate is hinged to the movable block and the bottom block respectively through hinges, as the movable block moves, the adjusting plate rotates around the hinge point with the bottom block, thereby adjusting the tilt angle of the nozzle.

[0039] Further: In step S4, the gas pressure value is determined through a regression model according to the material, thickness and lateral stiffness of the paper.

[0040] Compared with the prior art, the present invention has the following beneficial effects:

[0041] 1. The present invention constructs a multi-dimensional adjustment mechanism based on dynamic feedback. Through the synergistic effect of the horizontal position adjustment mechanism and the angle adjustment mechanism, precise control of the position and angle of the nozzle is achieved. The horizontal position adjustment mechanism drives the threaded connecting rod to rotate through a motor, driving the extension plate to make a horizontal displacement, so that the nozzle is always in the optimal action area in the horizontal direction of the paper; the angle adjustment mechanism drives the movable block to move through an electric telescopic rod, driving the adjustment plate to rotate, so that the spraying angle of the nozzle is adaptively matched with the deformation state of the paper, thereby effectively expanding the operation window of the system and improving the stretching effect of the paper.

[0042] 2. The present invention proposes an adaptive matching scheme for air flow parameters and paper characteristics. The parameter adaptation module of the control system can determine the optimal gas pressure value through a regression model according to the material, thickness and horizontal stiffness of the paper, ensuring that the best air flow support is obtained for papers with different materials, thicknesses and horizontal stiffnesses, realizing precise control of the air flow action field, and thus significantly improving the uniformity and consistency of the paper flattening effect.

[0043] 3. The present invention integrates a flexible control strategy driven by multi-source data. Through the organic combination of the air source module, the drive control module, the parameter adaptation module and the fault diagnosis module, the adaptability of the device to all categories of papers is enhanced, the stable operation efficiency of the system under the conditions of continuous production of multi-batch and multi-specification paper products is improved, and the manual debugging cost and error risk are reduced.

[0044] 4. The present invention realizes real-time monitoring of the operation state of the device through the transparent window on the outer wall of the control box. Combined with the intelligent judgment of the operation state of each component by the fault diagnosis module, the device has strong self-diagnosis and fault tolerance capabilities, effectively reducing the impact of sudden failures on the stable operation of the production line.

[0045] 5. Through the systematic integration of the structural design, control strategy and adaptive adjustment mechanism, the present invention constructs a set of intelligent processing devices with high precision, high versatility and high reliability for paper folding problems, improving the automation level of the sizing process and the product quality control ability. BRIEF DESCRIPTION OF THE DRAWINGS

[0046] Figure 1 is a three-dimensional structural schematic diagram of the device of the present invention;

[0047] Figure 2 is a cross-sectional schematic diagram of the control box in the structure of the present invention;

[0048] Figure 3 is Figure 2 an enlarged schematic diagram at A in

[0049] Figure 4 is a method for improving the paper folding of the paper discharged from the sizing machine in an embodiment of the present invention.

[0050] In the figure:

[0051] 1. Mounting base; 2. Control box; 3. Fixing frame; 4. Threaded connecting rod; 5. Connecting pipe; 6. Sprayer head; 7. Fixing plate; 8. Positioning rod; 9. Transparent window; 10. Controller; 11. Extension plate; 12. Threaded connection ring; 13. Bottom block; 14. Connecting plate; 15. Telescopic rod; 16. Movable block; 17. Adjusting plate. Specific embodiments

[0052] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all of them. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0053] In the description of the present invention, it should be noted that the orientation or positional relationship indicated by the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus cannot be construed as a limitation of the present invention. In addition, the terms "first", "second", and "third" are only used for descriptive purposes and cannot be construed as indicating or implying relative importance.

[0054] The present invention provides a device and method for improving the paper page folding of a sizing machine, aiming to solve the problems that the paper page is prone to folding, curling, etc. when the sizing machine outputs paper in the prior art. The device can dynamically adjust the arrangement of the sprayer head 6, the spray angle direction and the air pressure output according to the characteristics of the paper material, thickness, transverse width, etc. through a multi-dimensional collaborative adjustment structure and an intelligent feedback control mechanism, so as to realize the adaptive shaping and correction of different paper types.

[0055] The device of the present invention includes a mounting base 1, which is composed of a frame-shaped plate and two rectangular plates. This structural design makes the mounting base 1 have sufficient rigidity and can maintain structural stability in a high-speed operation environment. A control box 2 is fixedly installed on the top of the mounting base 1. The control box 2 is a rectangular hollow structure. An installation opening is provided on the outer wall of the control box 2, and a transparent window 9 is fixedly installed inside the installation opening. The transparent window 9 is made of transparent glass and is used to observe the operation state inside the control box 2.

[0056] A fixing bracket 3 is fixedly installed on the outer wall of the control box 2. The fixing bracket 3 has a rectangular ring-shaped cross-section. A threaded connecting rod 4 with external threads is movably installed inside the fixing bracket 3. The threaded connecting rod 4 is cylindrical in structure and is driven by a motor. An extension plate 11 is movably installed on the outer wall of the fixing bracket 3. The extension plate 11 is rectangular in structure. A threaded connection ring 12 that is threadedly connected to the threaded connecting rod 4 is fixedly installed on the outer wall of the extension plate 11. The threaded connection ring 12 is circular in structure. The above structures constitute a lateral position adjustment mechanism for precisely adjusting the lateral position of the nozzle 6.

[0057] A connecting pipe 5 is movably installed on the outer wall of the extension plate 11. The connecting pipe 5 is an arc-shaped hollow structure and is movably installed on the outer wall of the extension plate 11 through a hinge. A connecting plate 14 is fixedly installed at the bottom of the extension plate 11. The cross-section of the connecting plate 14 is L-shaped. A sliding groove is formed at the top of the connecting plate 14. An electric telescopic rod 15 is fixedly installed inside the sliding groove. A movable block 16 is movably installed inside the sliding groove. The movable block 16 is T-shaped in structure. The outer wall of the movable block 16 is fixedly connected to the output shaft of the electric telescopic rod 15. The top of the movable block 16 is movably installed with an adjusting plate 17 through a hinge. The adjusting plate 17 is rectangular in structure. A bottom block 13 is fixedly installed at the bottom of the connecting pipe 5. The bottom block 13 is a block with a trapezoidal cross-section. The adjusting plate 17 is hinged to the bottom block 13 through a hinge. These components together constitute an angle adjustment mechanism for precisely controlling the tilt angle of the nozzle 6.

[0058] A plurality of nozzles 6 are arranged on the outer wall of the connecting pipe 5. A controller 10 cable is arranged on the top of the mounting base 1. The controller 10 cable and the connecting pipe 5 are connected to each other through an elastic hose to ensure that the connection of the air circuit and the circuit will not be affected when the connecting pipe 5 adjusts its position and angle. These components constitute an air flow jetting mechanism for jetting air flow onto the paper sheet.

[0059] To ensure the stable installation of the device, two fixing plates 7 are symmetrically and fixedly installed on the outer wall of the mounting base 1. The fixing plates 7 are rectangular in structure. A fixing hole with internal threads is formed at the top of the fixing plate 7. A positioning rod 8 is threadedly connected inside the fixing hole. The positioning rod 8 is composed of a threaded rod and two cylindrical blocks. This design ensures the stability of the device during use.

[0060] The control system of the device of the present invention is arranged inside the control box 2 and includes a gas source module, a drive control module, a parameter adaptation module, and a fault diagnosis module. The gas source module is used to output gas with adjustable pressure; the drive control module is used to control the lateral position adjustment mechanism and the angle adjustment mechanism; the parameter adaptation module is used to calculate the optimal positions, angles, and gas pressures of the nozzles 6 according to the characteristics of the paper sheet; the fault diagnosis module is used to monitor the operating states of each component and perform fault diagnosis.

[0061] In another embodiment, the present invention further provides a method for improving the paper folding of the paper output from a sizing machine by using the above device, which specifically includes the following steps:

[0062] S1: Fix and install the device on the sizing machine.

[0063] Specifically, the mounting base 1 is stably installed on the sizing machine through the cooperation of the fixing holes on the fixing plate 7 and the positioning rod 8. The positioning rod 8 is screwed into the fixing hole with internal threads at the top of the fixing plate 7, so that the mounting base 1 is fixed at the corresponding position of the sizing machine, completing the basic installation of the device on the sizing machine. To ensure the stability of the overall structure, the mounting base 1 is designed with a rigid structure composed of a frame-shaped plate and two rectangular plates, which can keep the minimum deformation under the action of multi-dimensional forces. The mounting base 1 is attached to the installation surface of the sizing machine body through the rectangular fixing plate 7, and its tightness directly affects the micro-displacement generated during the adjustment process of the device. It is necessary to control the torque when screwing in the positioning rod 8 to ensure that the connection rigidity reaches the maximum.

[0064] To ensure that the screwing-in depth meets the requirements of structural rigidity, an expression for the relationship between the screwing-in depth d and the maximum stable torque τ is introduced:

[0065]

[0066] Among them, μ is the friction coefficient between the thread of the positioning rod 8 and the internal thread of the fixing hole, F n is the axial pre-tightening force applied to the positioning rod 8, r is the radius of the thread pitch diameter, h is the part where the screwing-in depth does not meet the standard, and d is the recommended screwing-in depth. By adjusting the screwing-in depth d to make h close to 0, τ can reach the upper limit of the stable range, improving the anti-interference ability of the device when adjusting the spray head 6 and preventing the spray deviation caused by the micro-vibration caused by the high-frequency adjustment of the spray head 6.

[0067] To make the screwing-in depth meet the requirements of structural rigidity, a static friction torque model can be introduced to evaluate the screwing-in state, and its expression is:

[0068]

[0069] Among them, τ s is the actually formed friction torque, μ is the friction coefficient, F a is the axial pre-tightening force, r is the effective radius of the thread, d is the current screwing-in depth, and d0 is the minimum stable depth. When the screwing-in depth d approaches d0, the torque growth curve gradually becomes stable, indicating that the mounting base 1 reaches a stable locking state at this time, which can effectively suppress the vibration caused by inertia and reaction force during the working process.

[0070] S2: Adjust the lateral position of the spray head 6 according to the lateral width of the paper sheet.

[0071] Specifically, start the control system inside the control box 2. The control system triggers the motor to operate, and the motor drives the threaded connecting rod 4 with external threads to rotate. Since the threaded connecting rod 4 is in threaded fit with the threaded connecting ring 12 fixed on the extension plate 11, as the threaded connecting rod 4 rotates, the extension plate 11 makes a horizontal displacement adjustment along the outer wall of the fixed frame 3, thereby changing the lateral position of the connecting pipe 5 and the nozzle 6 to preliminarily align with the paper sheet.

[0072] During the lateral position adjustment of the nozzle 6, the motor drives the threaded connecting rod 4 to rotate. Combining with the threaded ring to push the extension plate 11 to displace horizontally, the displacement Δx should satisfy the following control precision evaluation relationship:

[0073]

[0074] Where P is the lead of the thread, N is the number of turns of the motor rotation, and M is the reduction ratio of the motor. By precisely controlling N and M, the movement of the extension plate 11 can be controlled within the sub-millimeter range, realizing the precise alignment of the nozzle 6 with the paper sheet. According to the real-time monitoring data of the lateral width of the paper sheet and the paper output position, a one-to-one mapping lateral displacement adjustment table can be constructed, so that the nozzle 6 is in the optimal lateral action position at the initial operation stage, thereby maximizing the air flow stretching effect.

[0075] By precisely controlling the number of turns N of the motor rotation, the displacement Δx of the extension plate 11 satisfies:

[0076] Δx = P·N·η

[0077] Where P is the lead of the thread, η is the transmission system efficiency coefficient, and N is the number of turns of the motor rotation. The system reads the value of N in real time through an encoder or the built-in pulse feedback of the stepping motor, and makes fine adjustments in combination with the lateral displacement target, so that the nozzle 6 is always in the optimal air flow action area within the lateral range of the paper sheet.

[0078] S3: Adjust the tilt angle of the nozzle 6 according to the undulation of the paper sheet surface.

[0079] Specifically, the electric telescopic rod 15 is started, and its output shaft pushes the movable block 16 to move in the chute at the top of the connecting plate 14. Since the adjusting plate 17 is hinged to the movable block 16 and the bottom block 13 respectively through hinges, as the movable block 16 moves, the adjusting plate 17 rotates around the hinge point with the bottom block 13, thereby adjusting the tilt angle of the connecting pipe 5 and the nozzle 6, so that the nozzle 6 can accurately align with a specific position of the paper sheet.

[0080] After the electric telescopic rod 15 is started, its output shaft pushes the movable block 16 to move linearly along the chute, and the adjusting plate 17 rotates around the hinge point at the bottom block 13 to form an inclination angle α. By adjusting the stroke s of the movable block 16, the dynamic adjustment of the inclination angle α of the nozzle 6 is realized, so that the action center of the air flow ejected by the nozzle 6 always aligns with the area where the paper surface forms a crease or curl. Combining the inclination angle adjustment with the correction model of the air flow propagation path, at different nozzle 6 angles α, the air flow impact position y satisfies:

[0081] y = L·tan(α)

[0082] where L is the vertical distance between the nozzle 6 and the paper. Combining with the height H fluctuation value of the paper during transmission, the initial angle α0 of the nozzle 6 is set to tan -1 (y0 / L), and during operation, the adjustment angle is iteratively optimized with Δα as the step size, so that y dynamically fits the change trend of H, ensuring uniform force on the paper.

[0083] According to the geometric transformation relationship, the relationship between the inclination angle α of the nozzle 6 and the elongation s of the telescopic rod 15 satisfies:

[0084]

[0085] where L is the fixed-length support arm, s is the current length of the telescopic rod 15, and d is the distance between the nozzle 6 and the movable block 16. During the adjustment process, the system obtains the current α value in real time through an angle sensor or a dihedral angle estimation model, and dynamically adjusts the telescopic length s according to the height and depression data of the paper surface, so that the spraying direction of the nozzle 6 continuously fits the normal direction of the paper surface, thereby improving the adhesion rate and impact efficiency of the air flow on the complex paper surface.

[0086] S4: Jet air flow with a pressure of 4 - 6 kg on the paper through the nozzle 6, so that the paper unfolds from the middle to both sides under the action of the air flow and the folding is eliminated.

[0087] Specifically, the air source in the control box 2 outputs pressure gas of 4 - 6 kg, and the gas is transported to the nozzle 6 through the connecting pipe 5. The nozzle 6 ejects a strong air flow, which acts on the paper output from the sizing machine.

[0088] The equipment detection before the control system is started needs to cover all drive and execution components. Among them, the control signals of the motor and the electric telescopic rod 15 need to be checked for voltage, current, and communication consistency to ensure stable response ability during program call. For the air source part, it is necessary to detect through a sensor whether the deviation between the actual output pressure P and the set value P0 satisfies:

[0089] |P - P0| ≤ δ P

[0090] where δ Pis the maximum pressure deviation allowed by the system, ensuring the stability of the output air flow and providing continuous kinetic energy support for the subsequent action of the nozzle 6.

[0091] The stable maintenance of the output value of the pressurized gas in the range of 4 to 6 kilograms is the prerequisite for achieving the consistency of the air flow action. A highly sensitive pressure feedback system is installed in the control box 2, which monitors the deviation between the pressure value p and the set value p0 in real time through a closed-loop regulation mechanism, and performs a dynamic pressure regulation process based on the PID algorithm. Its calculation model is:

[0092]

[0093] where u(t) is the output value of the adjustment signal, e(t) is the current error, and K p 、K i 、K d are the proportional, integral, and differential coefficients respectively. Through the comprehensive judgment of the current pressure deviation, historical cumulative error, and error change trend, this algorithm quickly adjusts the opening of the electronically controlled valve, stably outputs the air pressure, and ensures the consistency and timeliness of the air flow intensity of the rear-end nozzle 6.

[0094] During the air flow injection process, the gas pressure value is determined through a regression model according to the material, thickness, and transverse stiffness of the paper sheet, ensuring that papers with different materials, thicknesses, and transverse stiffnesses all obtain the best air flow support and achieving precise control of the air flow action field. During the air source output stage, the pressure regulation system needs to set the most suitable gas pressure P p 、thickness d p and transverse inertia coefficient I p for the paper sheet, and realizes dynamic pressure setting through the following adaptation model: * P

[0095] P * =k1·ρ p +k2·d p +k3·I p

[0096] where k1, k2, and k3 are regression coefficients obtained through training a large number of experimental samples, representing the weights of each parameter on the required pressure, is the transverse moment of inertia of the paper sheet per unit length, reflecting the ability of the paper sheet to resist bending. The target pressure P * output by this model is output in real time by the precision pressure regulation device in the control box 2 and closed-loop verified, ensuring that the air flow at the nozzle 6 remains stable and effective under different paper types, neither causing air flow failure due to insufficient pressure nor generating the risk of paper sheet tearing or drifting due to overpressure.

[0097] The number of nozzles 6 is multiple, and they are distributed according to the symmetric layout principle in the air source shunt structure. Each nozzle 6 has an independent air supply channel and an angle adjustment mechanism, so as to construct an approximately parallel uniform air flow field on the paper surface. During the spraying process, the strong air flow impacts the paper surface, enabling it to overcome gravity and the initial folding inertia, and gradually unfold to form a tensioned state. By establishing a corresponding relationship between the position (x i , y i ) of each nozzle 6 and the coordinates (x p , y p ) of the local crease area of the paper, the system introduces a two-dimensional air flow action function Φ(x, y), which is defined as:

[0098]

[0099] where Φ(x, y) is the air flow action intensity distribution function, n is the number of nozzles 6, A i is the instantaneous air flow intensity of the i-th nozzle 6, σ is the air flow diffusion coefficient, and (x i , y i ) is the projection center of the nozzle 6. By adjusting the angle and air pressure of each nozzle 6, the Φ value in the paper folding area is made to reach the action threshold Φ t , so as to achieve local flattening. The system conducts a hot zone analysis on the distribution of Φ(x, y). When it is found that the local Φ value is insufficient and the paper cannot be fully unfolded, the angle adjustment and pressure compensation mechanism is immediately triggered, and the air flow is concentrated on the key area to improve the paper unfolding rate and flatness.

[0100] S5: Monitor the running state of the device in real time and perform maintenance operations when abnormalities are found.

[0101] Specifically, the staff observes the running state inside the control box 2 through the transparent window 9 at the installation opening on the outer wall of the control box 2. If any abnormality is found, maintenance operations are carried out in a timely manner to ensure the continuous and stable operation of the device.

[0102] To improve the objectivity of fault judgment and the functional verification efficiency after system recovery, the control system embeds an operating state evaluation model and introduces a discrimination mechanism based on the state residual r(t), which is defined as:

[0103] r(t) = ||y obs (t) - y pred (t)||

[0104] where r(t) is the state residual at time t, y obs (t) is the system response value obtained in real time through the sensor, and y pred (t) is the reference output predicted according to the ideal system model and control instructions. This residual reflects the deviation degree between the current state of the device and the theoretical response. When r(t) exceeds the threshold rt Automatically record abnormal points in real time, and trigger the fault indication mechanism and the associated alarm process. Through the trend analysis of the residual curve, the staff can judge the development trend of the abnormality and the possible fault location, so as to carry out maintenance operations more pertinently.

[0105] After replacing or repairing the faulty components, the device needs to be restarted and repeat all the operation steps according to the complete commissioning process to verify whether the restored system stability and air flow control effect meet the standards. At this time, compare the paper tension index T output by the system with the historical optimal state T opt and calculate the recovery coefficient η of the tension effect after repair:

[0106]

[0107] The closer η is to 1, the closer the current paper unfolding state is to the best, and the more complete the system repair effect is. This coefficient is not only used for the quality verification after on-site maintenance, but also serves as an important basis for the analysis of the aging trend of equipment status during the long-term operation of the system, so as to construct a preventive maintenance plan based on operation data, improve the reliability of the device and the stability of paper shaping, and comprehensively ensure the long-term performance and fault controllability of the entire system under high-frequency operating conditions.

[0108] For the adaptability control of different types of paper, the diameter of the nozzle 6, the number of spray holes and the spraying angle need to be selected according to parameters such as the material of the paper (such as coated paper, kraft paper, and printing paper), the thickness d p and the transverse width w p etc. to ensure that the air flow coverage, action depth and penetration are in the optimal matching state. During the adjustment of the position and tilt angle of the nozzle 6, the system calculates the optimal tilt angle θ * and the central position x of the nozzle 6 * and realizes positioning through the motor-driven threaded connecting rod 4 and the electric telescopic rod 15. This position-angle combination satisfies the condition of the most balanced overall unfolding tension distribution of the paper, and the constraint expression is:

[0109]

[0110] where T(x,θ) represents the local tension distribution of the paper at the position x of the nozzle 6 and the spraying angle θ, is the tension gradient, and T min is the minimum tension strength required to ensure the unfolding effect. This optimization goal physically requires the most uniform tension distribution within the range of the air flow ejected by the nozzle 6, so as to avoid local wrinkles or creases. Specifically during implementation, the control system performs discrete gradient evaluation by gradually adjusting the position of the nozzle 6 and reading the tension feedback signal, and quickly converges to the optimal solution in combination with the local search algorithm.

[0111] In actual operation, the crease pattern of the paper sheet has complex randomness. Therefore, the system needs to continuously obtain the surface state data of the paper sheet, combine the high-frequency image signals provided by structured light or linear array sensors for crease recognition and spatial modeling, and quantify the current degree of unfolding as the paper sheet tension index T. This index participates in the PID control and air flow distribution adjustment process as a feedback signal to achieve dynamic adaptive closed-loop control, thereby improving the paper sheet shaping quality and the stable operation level of the equipment.

[0112] Through the system integration of the above device structure design, control strategy and adaptive adjustment mechanism, the present invention constructs a set of intelligent processing devices with high precision, high versatility and high reliability for the problem of paper sheet folding, improves the automation level of the sizing process and the product quality control ability, and has significant industrial application and promotion value.

[0113] The above embodiments are only for illustrating the technical concept and characteristics of the present invention, and the purpose is to enable those who are familiar with this technology to understand the content of the present invention and implement it accordingly, and cannot be used to limit the protection scope of the present invention. Any equivalent transformation or modification made according to the spirit and essence of the present invention should be covered within the protection scope of the present invention.

Claims

1. A device for improving the folding of the paper sheet output from a sizing machine, characterized in that, Comprising: A mounting base for fixedly installing on a sizing machine; A control box fixedly installed on the top of the mounting base; A lateral position adjustment mechanism arranged on the outer wall of the control box for adjusting the lateral position of the nozzle; An angle adjustment mechanism connected to the lateral position adjustment mechanism for adjusting the tilt angle of the nozzle; An air flow injection mechanism comprising a connecting pipe connected to the lateral position adjustment mechanism and the angle adjustment mechanism and a plurality of nozzles arranged on the outer wall of the connecting pipe for injecting air flow onto the paper; A control system arranged in the control box for controlling the operation of the lateral position adjustment mechanism, the angle adjustment mechanism and the air flow injection mechanism.

2. The device for improving the paper page folding of the sizing machine according to claim 1, wherein, The lateral position adjustment mechanism comprises: A fixing frame fixedly installed on the outer wall of the control box; A threaded connecting rod movably installed inside the fixing frame and driven to rotate by a motor; An extension plate movably installed on the outer wall of the fixing frame; A threaded connection ring fixedly installed on the outer wall of the extension plate and threadedly connected to the threaded connecting rod.

3. An apparatus for improving the paper page folding of the paper output from a sizing machine according to claim 2, characterized in that, The angle adjustment mechanism comprises: A connecting plate fixedly installed at the bottom of the extension plate and provided with a sliding groove at the top; An electric telescopic rod fixedly installed inside the sliding groove; A movable block movably installed inside the sliding groove and fixedly connected to the output shaft of the electric telescopic rod; An adjustment plate is movably installed on the top of the movable block through a hinge; A bottom block fixedly installed at the bottom of the connecting pipe and hinged to the adjustment plate through a hinge.

4. The device for improving the paper page folding of the sizing machine according to claim 3, wherein The connecting pipe of the air flow injection mechanism is an arc-shaped hollow structure and is movably connected to the extension plate through a hinge, and the connecting pipe is connected to the control box through an elastic hose.

5. An apparatus for improving the paper page folding of the paper output from a sizing machine according to claim 1, characterized in that, The control system comprises: An air source module for outputting gas with adjustable pressure; A drive control module for controlling the lateral position adjustment mechanism and the angle adjustment mechanism; A parameter adaptation module for calculating the optimal nozzle position, angle and gas pressure according to the paper properties; A fault diagnosis module for monitoring the operation status of each component and performing fault diagnosis.

6. The device for improving the paper page folding of the sizing machine according to claim 1, characterized in that, An installation opening is provided on the outer wall of the control box, and a transparent window is fixedly installed inside the installation opening for observing the operation status inside the control box.

7. A method for improving the paper folding of the paper output from a sizing machine by using the device according to any one of claims 1-6, characterized in that, Including the following steps: S1: Fix the device on the sizing machine; S2: Adjust the lateral position of the nozzle according to the lateral width of the paper; S3: Adjust the tilt angle of the nozzle according to the height and depression of the paper surface; S4: Inject air flow with a pressure of 4-6 kg onto the paper through the nozzle, so that the paper is stretched from the middle to both sides under the action of the air flow to eliminate wrinkles; S5: Monitor the operation status of the device in real time and perform maintenance operations when abnormalities are found.

8. The method according to claim 7, wherein In step S2, the threaded connecting rod is driven to rotate by a motor, and the threaded connecting rod is in threaded cooperation with the threaded connection ring on the extension plate. As the threaded connecting rod rotates, the extension plate makes a horizontal displacement adjustment along the outer wall of the fixing frame, thereby changing the lateral position of the nozzle.

9. The method according to claim 7, wherein In the step S3, the movable block is pushed by the electric telescopic rod to move in the chute on the top of the connecting plate. Since the adjusting plate is hinged to the movable block and the bottom block respectively through hinges, as the movable block moves, the adjusting plate rotates around the hinge point with the bottom block, thereby adjusting the tilting angle of the nozzle.

10. The method according to claim 7, characterized in that In the step S4, the gas pressure value is determined through a regression model according to the material, thickness and transverse stiffness of the paper sheet.

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