A high-speed precise slitting system and process for decorative paper based on double air plate deflection

Abstract

The present application relates to the technical field of decorative paper processing, and specifically relates to a high-speed precise slitting system and process for decorative paper based on double air plate deviation correction, which comprises an air floatation flow stabilization unit, a visual detection unit, a differential pressure air floatation deviation correction unit, a negative pressure dust removal unit and a zero-gap slitting unit. The present application overcomes the technical drawbacks of traditional mechanical deviation correction systems, such as large inertia, response lag and easy scratching of the paper surface. The present application uses the dynamic pressure difference of left and right air chambers to build a transverse fluid shear force to drive the paper band to reset, which improves the deviation correction response speed from hundreds of milliseconds to milliseconds, and the whole process is contactless and suspended, which effectively protects the delicate printing layer of the decorative paper. In combination with the sub-pixel visual filtering algorithm and the unique synergistic negative pressure dust removal mechanism, not only the vibration interference and static dust pollution under high-speed operation are eliminated, but also energy-saving dust removal is achieved by using the overflow air flow of the air plate. Finally, through the zero-gap knife edge cutting and slip difference shaft tension compensation, the secondary shaking in the free span is eliminated.

Description

Technical Field

[0001] This invention relates to the field of decorative paper processing technology, specifically to a high-speed and precise slitting system and process for decorative paper based on dual-air plate alignment. Background Technology

[0002] Decorative paper is a key surface material for products such as engineered wood flooring and furniture veneers. With the increasing production capacity of the modern furniture and building materials industries, extremely high demands are being placed on the production efficiency and finished product quality of the decorative paper slitting process. Currently, the operating speed of mainstream high-speed slitting machines has gradually exceeded 300m / min and is moving towards 500m / min.

[0003] In the high-speed slitting process of decorative paper, "deviation" and "flutter" are the two major challenges affecting slitting accuracy. Existing technical solutions have the following significant drawbacks: 1. Response Lag of Traditional Mechanical Tracking: Existing slitting machines typically employ EPC (Edge Position Control) or LPC (Line Position Control) systems, whose actuators are mostly motor-driven mechanical guide roller frames. When paper misalignment is detected, the motor needs to drive the heavy guide roller frame to move as a whole to correct it. However, decorative paper is a low basis weight (typically 70-80 g / m²) and low stiffness flexible material. Under the impact of high-speed airflow above 300 m / min, the paper strip will generate high-frequency aerodynamic flutter. Due to its large inertia, the response time of traditional mechanical tracking systems is usually on the order of hundreds of milliseconds, which cannot keep up with the high-frequency vibration of the paper strip. This results in a serious lag in the tracking action, causing the slitting edge to appear wavy, and making it difficult to stably control the accuracy within ±0.2 mm.

[0004] 2. Surface damage caused by contact-based web guiding: Most existing web guiding and flow stabilization devices rely on physical contact between guide rollers / pressure rollers and the paper surface to apply friction. Decorative paper often has intricate wood or stone grain patterns printed on it and requires resin impregnation. Mechanical friction at high speeds can easily create fine scratches on the paper surface or cause powdering of the printed layer. This is a fatal quality defect for high-grade decorative paper, directly leading to an increased scrap rate in subsequent laminating processes.

[0005] 3. Lack of an effective dust removal mechanism: During high-speed slitting, paper breakage and friction generate a large amount of fine paper dust. Since decorative paper is an insulator, high-speed friction generates static electricity of up to several thousand volts, causing the paper dust to adhere firmly to the paper surface. Existing equipment typically only has simple air nozzles or passive brushes, which cannot effectively remove the dust attracted by static electricity. Once this residual dust enters the subsequent impregnation process, it will form obvious "pits" or "white spots" on the board surface, severely affecting the product's appearance.

[0006] 4. Excessive free span leads to decreased cut quality: In traditional equipment layouts, to allow space for the mechanical correction frame, there is often a long distance between the correction device and the slitting blade assembly (i.e., "free span"). At high speeds, the unsupported paper tape is prone to secondary drift or micro-vibration the moment it enters the blade, resulting in burrs, serrations, or wavy edges on the cut surface, failing to meet the "zero-defect" end face requirements of high-end customers.

[0007] In summary, existing decorative paper slitting technologies are insufficient to simultaneously meet the triple requirements of "ultra-high-speed operation," "micron-level precision," and "non-destructive surface." Therefore, developing a precision slitting process that utilizes fluid dynamics principles to achieve non-contact, high-response speed, and dust removal capabilities has become a pressing technical challenge in this field. Summary of the Invention

[0008] To achieve the above objectives, the present invention provides the following technical solution: This invention provides a high-speed and precise slitting process for decorative paper based on dual-air-plate alignment, comprising the following steps: S1: The decorative paper to be slit is introduced into the first-stage stabilizing air plate area with a set tension. Constant-pressure airflow is injected through micro-holes distributed on the surface of the stabilizing air plate, forming a continuous supporting air film on the lower surface of the decorative paper. The fluid adhesion effect is used to adsorb the decorative paper and suppress its longitudinal flutter during high-speed transport; S2: A visual detection unit located downstream of the stabilizing air plate collects edge position signals or printed marking line signals of the decorative paper in real time, and transmits the collected signals to a controller. The controller calculates the current lateral offset and offset direction of the decorative paper based on a preset reference position; S3: The decorative paper enters the second-stage alignment air plate area along the transport path. The alignment air plate physically separates the decorative paper in the lateral width direction. The air is divided into a left air chamber and a right air chamber. The controller dynamically adjusts the air supply pressure ratio between the left and right air chambers through an electric proportional valve based on the lateral offset calculated in step S2. An asymmetric lateral pressure gradient is constructed on the bottom surface of the decorative paper. The lateral fluid shear force generated by this pressure gradient drives the decorative paper to perform contactless reset on the opposite side of the offset direction. S4: A negative pressure dust collection groove is set in the transition area between the stabilizing air plate and the correcting air plate. The high-speed airflow overflowing from the air plate in steps S1 and S3 blows the free dust on the surface of the decorative paper and removes the dust-laden airflow through the negative pressure dust collection groove. S5: After the decorative paper is corrected and reset in S3, it is directly fed into the slitting knife group while maintaining the rigid support of the air float. After longitudinal slitting, it is wound up by the rewinding unit.

[0009] Furthermore, in step S1, the surface configuration of the stabilizing air plate is a large-radius convex arc surface along the running direction of the decorative paper. The micropores are distributed in an alternating array on the convex arc surface, and the axis of each micropore is inclined towards the running direction of the decorative paper with an included angle of 30° to 60°. The inclined jet airflow generates a viscous traction component along the running direction on the lower surface of the decorative paper to tighten the paper strip.

[0010] Furthermore, the flow stabilizing plate is equipped with a double-layer flow equalization chamber. The external air source enters the second-layer chamber after being buffered by the first-layer chamber and rectified by the flow equalization plate, and is then ejected through the microholes to ensure that the static pressure fluctuation range of the formed air film is controlled within ±2%.

[0011] Furthermore, in step S2, the visual detection unit uses a high-speed linear CCD camera with a sampling frequency of not less than 10kHz in conjunction with a parallel backlight. When calculating the lateral offset, the controller first uses a sub-pixel edge detection algorithm to lock the edge coordinates of the decorative paper based on the pixel grayscale gradient. Then, it processes the continuously acquired edge coordinate signals through a moving average filtering algorithm or a Kalman filtering algorithm to remove random noise caused by high-frequency paper flutter and extract only the low-frequency component representing the deviation of the actual running trajectory as the final lateral offset output to step S3.

[0012] Further, in step S3, The controller employs a PID closed-loop control algorithm and pre-sets a basic buoyancy pressure value that can maintain the stable suspension of the decorative paper. When a lateral offset signal is received, the controller simultaneously controls the air pressure in the left and right air chambers in differential adjustment mode, raising the pressure in one air chamber to a certain level and lowering the pressure in the other air chamber to a certain level. ,in This is the corrected pressure value calculated based on the offset; the controller has a preset maximum differential pressure threshold to limit... Not exceeding the basic buoyancy pressure value of This is to prevent the decorative paper from arching or wrinkling on the surface of the correction air plate due to excessive lateral pressure gradient.

[0013] Furthermore, in step S4, the negative pressure dust collection trough spans the full width of the decorative paper, and the two sides of the trough opening are provided with smooth guide arc surfaces with a radius of curvature of 2mm to 5mm to prevent the decorative paper from scratching the trough opening under negative pressure. A high-voltage ion generator is integrated at the entrance of the negative pressure dust collection trough to emit positive and negative ion beams to the surface of the decorative paper to eliminate surface static charge, causing the adsorbed dust on the surface of the decorative paper to dissociate. Subsequently, the dust is drawn into the negative pressure dust collection trough by the converging airflow overflowing from the stabilizing air plate and the correcting air plate, forming a three-stage dust removal mechanism of static electricity removal, airflow stripping, and negative pressure capture.

[0014] Furthermore, in step S5, the slitting blade assembly adopts a shearing structure, including an actively driven lower blade shaft and a pneumatically clamped upper circular blade; the outlet end of the correction air plate extends to a position less than 50mm away from the biting point of the slitting blade assembly, minimizing the free span of the decorative paper after it leaves the air-bearing support. After being slit, multiple decorative paper strips are wound up by a staggered dual-station differential shaft. The friction ring assembly inside the differential shaft automatically compensates for tension differences based on the changes in the roll diameter of each paper strip, ensuring that the end face uniformity error of all slit sub-rolls is controlled within ±0.2mm.

[0015] A high-speed, precise slitting system for decorative paper based on dual-air-plate alignment includes the following units arranged sequentially along the paper's transport direction: an air-float stabilizing unit, comprising a first-stage stabilizing air plate with a micro-pore array distributed on its surface and connected to a constant-pressure air source, used to establish a stable supporting air film and eliminate longitudinal flutter before the decorative paper enters the slitting zone; a visual inspection unit, located downstream of the air-float stabilizing unit, including a high-frequency linear array camera and a matching light source, configured to acquire the edge position or marker line signal of the decorative paper in real time; and a differential-pressure air-float alignment correction unit, comprising a second-stage alignment correction air plate, an electro-proportional valve group, and a central controller; the alignment correction air plate is physically divided into a non-communicating left and right air chambers in the lateral width direction, and the electro-proportional valve group independently controls the left and right air chambers respectively. The air intake pressure of the chamber; a negative pressure dust removal unit, arranged at the physical gap between the air flotation stabilization unit and the differential pressure air flotation correction unit, including a dust suction groove spanning the width of the paper web and a negative pressure generating device, used to remove dust from the surface of the decorative paper; a zero gap slitting unit, arranged adjacent to the end of the differential pressure air flotation correction unit, including a slitting knife group and a winding mechanism; wherein, the central controller is electrically connected to the vision detection unit and the electro-proportional valve group respectively, and is configured to execute the following control logic: receive the lateral offset signal fed back by the vision detection unit, calculate the correction value through a PID algorithm, and drive the electro-proportional valve group to establish a pressure difference corresponding to the offset between the left air chamber and the right air chamber, thereby constructing a fluid pressure gradient on the surface of the correction air plate to drive the decorative paper to laterally reset.

[0016] Compared with the prior art, the beneficial effects of the present invention are: This invention overcomes the technical drawbacks of traditional mechanical web guiding systems, such as large inertia, slow response, and susceptibility to paper surface abrasion. It utilizes the dynamic pressure difference between the left and right air chambers to create lateral fluid shear force to drive the paper tape repositioning, improving the web guiding response speed from hundreds of milliseconds to milliseconds. Furthermore, the non-contact suspension throughout the process effectively protects the delicate printing layer of the decorative paper. Combined with a sub-pixel visual filtering algorithm and a unique collaborative negative pressure dust removal mechanism, it not only eliminates flutter interference and electrostatic dust pollution under high-speed operation but also achieves energy-saving dust removal through the overflow airflow from the air plate. Finally, through zero-gap blade entry and slip shaft tension compensation, it eliminates secondary vibration within the free span, achieving excellent performance indicators of ±0.1mm slitting accuracy and ±0.2mm end-face uniformity under high-speed conditions above 300m / min, significantly improving the production efficiency and yield of high-grade decorative paper. Attached Figure Description

[0017] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below.

[0018] Figure 1 This is a process flow diagram of the present invention; Figure 2 This is a cross-sectional view of the S3 dual-zone differential pressure correction principle of the present invention. Detailed Implementation

[0019] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of the present invention.

[0020] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this invention are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of the invention described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover a non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but includes other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0021] The present invention will now be described in further detail with reference to the accompanying drawings: Example: As shown in the figure S1: The decorative paper to be cut is introduced into the first-stage stabilizing air plate area with a set tension. Constant pressure airflow is injected through the micropores distributed on the surface of the stabilizing air plate to form a continuous supporting air film on the lower surface of the decorative paper. The fluid adhesion effect is used to adsorb the decorative paper and suppress its longitudinal flutter during high-speed transmission. The main purpose is to eliminate aerodynamic instabilities (such as high-frequency flutter and edge jitter) caused by high-speed operation before the decorative paper enters the high-precision detection and correction stage, and to convert the paper strip from a "flexible relaxed state" to an "air-floating tensioned state". The specific implementation process and device structure are as follows: S101: The decorative paper to be cut is introduced into the first-stage flow stabilizing plate area. To achieve optimal fluid adhesion, the flow stabilizing plate in this embodiment does not use a traditional flat plate structure, but is designed as a large-radius convex arc-shaped surface extending along the direction of the decorative paper's movement (MD direction). The radius of curvature of this arc-shaped surface... With a setting of 800mm-1500mm, this arc design allows the decorative paper to naturally form a wrapping corner when passing over the air plate, using geometric structure to help establish tension.

[0022] S102: The internal structure of the air stabilizing plate adopts a "double-layer flow equalization chamber" to solve the problem of uneven air pressure in traditional air plates causing localized paper drift. Primary buffer chamber (lower layer): The external high-pressure air source first enters the bottom buffer chamber, where the airflow speed decreases, the dynamic pressure is converted into static pressure, and the air source pulsation is eliminated.

[0023] Secondary pressure regulating chamber (upper layer): Gas passes through the rectifier plate (flow equalization plate) between the primary and secondary stages and enters the upper pressure regulating chamber. The rectifier plate has a high density of throttling orifices to ensure extremely uniform gas pressure distribution entering the secondary pressure regulating chamber, with pressure fluctuations controlled within a certain range. Within.

[0024] S103: On the top surface of the air stabilizing plate (i.e., the working surface opposite to the decorative paper), there are micropores arranged in a staggered array: The preferred micropore diameter The hole spacing is ; Inclination Angle: Unlike vertical spraying, in this embodiment, the axis of the micro-orifice is inclined towards the running direction of the decorative paper, forming an angle with the tangential plane of the air plate. The included angle.

[0025] When constant-pressure gas is ejected from an inclined micro-orifice, the reaction force generated by the airflow Decomposed into two components: vertical component Provides vertical buoyancy, allowing the decorative paper to suspend approximately above the air plate surface. The height creates a non-contact air film support, preventing scratches on the paper surface.

[0026] Horizontal component This generates a viscous traction force along the direction of travel. This force acts on the lower surface of the paper strip, effectively creating a "pneumatic ironing" effect, tightening the paper strip longitudinally and effectively eliminating tiny wrinkles in the middle of the paper.

[0027] In this embodiment, the Coanda effect is utilized to suppress flutter. Because the surface of the air plate is convex, the high-speed jet tends to adhere to the curved surface. This wall-attached jet creates a slightly negative pressure zone relative to atmospheric pressure within the air film layer (although the overall pressure is positive, there is a localized negative pressure tendency at the point of highest flow velocity). This force "draws" the decorative paper towards the air plate, but it is separated by the air film. This balanced state of "both supporting and drawing in" greatly enhances the fluid stiffness of the air film. Compared to a freely suspended paper strip, the paper strip treated in S1 exhibits motion characteristics similar to a rigid plate, with its Z-axis amplitude compressed to below 0.5mm, providing an extremely stable physical basis for the precise capture by the CCD camera in the subsequent S2 step.

[0028] S2: Using a vision detection unit located downstream of the stabilizing air plate, the edge position signal or printed mark line signal of the decorative paper is collected in real time, and the collected signal is transmitted to the controller. The controller calculates the current lateral offset and offset direction of the decorative paper in combination with the preset reference position.

[0029] The specific implementation process is as follows: S201: The visual inspection unit is rigidly mounted in the transition area between the stabilizing air plate (S1) and the subsequent correcting air plate (S3). Considering the high-speed running characteristics of the decorative paper, this embodiment abandons the traditional area scan camera and selects a high-frequency linear scan CCD camera. The line frequency setting of this camera is not lower than... This means scanning 10,000 times per second to ensure continuous, uninterrupted edge image data even at high speeds. The pixel resolution is preferably 4096 pixels or higher to meet high-precision detection requirements. A high-brightness parallel LED backlight is placed below the decorative paper, and the line scan camera is positioned vertically above the paper. This "transmissive" lighting method utilizes the opacity of the decorative paper to create a high-contrast "black and white silhouette" in the camera's field of view, greatly reducing the interference of printed pattern colors on edge extraction and ensuring a high signal-to-noise ratio for edge signals.

[0030] S202: After receiving the raw grayscale image data from the camera, the controller does not directly use the integer coordinates of the pixels, but instead executes a sub-pixel algorithm: The controller samples the pixel grayscale values ​​of the image edge regions. Specifically, the controller selects pixels centered on the edges. The pixel matrix is ​​used to perform regression analysis on the gray-level distribution within the matrix using a Gaussian curve fitting model. This process aims to construct a continuous gray-level gradient function and solve for the extreme points of the first derivative of this function (i.e., the locations with the largest gray-level change rates). Through this calculation, the system can overcome the discrete limitations of physical pixels and locate theoretically sub-pixel-level edge coordinates.

[0031] By identifying the location with the largest grayscale change rate, edge coordinates accurate to 0.1 pixels are calculated. This means that even if the physical pixel accuracy is 0.05mm, the theoretical detection accuracy of the system can reach 0.005mm after algorithm optimization, which meets the requirements for accurate segmentation.

[0032] S203: During high-speed slitting, even after flow stabilization via S1, decorative paper inevitably experiences slight high-frequency random fluctuations (usually caused by airflow disturbances or mechanical resonance). If the controller directly relies on the original coordinates... When correcting errors, the actuator will move frequently, causing system oscillations or even motor overheating. Therefore, this embodiment incorporates a Kalman filter or moving average filter module within the controller. Signal separation: The filtering algorithm decomposes the acquired position signal into two parts: High-frequency noise components: These represent random paper jitter and should be filtered out or ignored.

[0033] Low-frequency trend component: represents the actual deviation trajectory of the paper.

[0034] Output calculation: The controller extracts only the processed low-frequency components as the effective position values. And compare it with the system's preset reference zero position. The comparison is performed to calculate the final deviation control signal. .

[0035] S204: The controller will calculate the deviation. The deviation direction is packaged in real time and sent to the electro-proportional valve group in step S3 with a communication cycle of milliseconds as the input command for subsequent differential pressure regulation.

[0036] S3: The decorative paper enters the second-stage correction air plate area along the transport path. The correction air plate is physically divided into a left air chamber and a right air chamber in the lateral width direction. The controller dynamically adjusts the air supply pressure ratio between the left air chamber and the right air chamber through an electric proportional valve according to the lateral offset calculated in step S2. An asymmetric lateral pressure gradient is constructed on the bottom surface of the decorative paper. The lateral fluid shear force generated by this pressure gradient drives the decorative paper to perform contactless reset to the opposite side of the offset direction.

[0037] The specific implementation process is as follows: S301: Utilizes fluid dynamics principles to generate a corrective force by altering the pressure distribution of the air film on the lower surface of the decorative paper. Physical structure of the correction air plate: The second-stage correction air plate maintains a similar arc-shaped or planar structure to the first-stage flow stabilizing air plate in appearance, but there are fundamental differences in its internal structure: Physical partition: A physical partition is set in the internal air chamber of the correction air plate along the center line of the paper tape running direction, which completely seals and separates the air chamber into the left air chamber and the right air chamber.

[0038] Independent air supply: The left and right air chambers each have independent air inlets, each connected to the output of a precision electro-proportional valve. This structural design allows for independent and decoupled control of the air pressure under the left and right halves of the paper tape.

[0039] S302: During system startup or when the paper tape is in the centering state, the controller outputs the same control voltage to both the left and right air chambers, maintaining a constant basic float pressure in both air chambers. The decorative paper is supported by uniform air pressure across its entire width, and is stably suspended about 0.5mm above the air plate, in a state of equilibrium.

[0040] S303: When the visual detection unit in step S2 determines that the decorative paper has shifted laterally (e.g., shifted to the left), When the controller immediately activates the differential control mode: Pressure gradient construction: The controller instructs the left-side electro-proportional valve to increase its opening, causing the pressure in the left-side air chamber to rise to [a certain value]. Simultaneously, the right-side electro-proportional valve is instructed to reduce its opening, thereby lowering the pressure in the right-side air chamber to [a certain value]. .

[0041] Generation of fluid shear force: At this point, a lateral pressure gradient decreasing from left to right is formed in the air film layer beneath the decorative paper. According to the principles of fluid dynamics, airflow always tends to flow from high-pressure areas to low-pressure areas. Therefore, air molecules in the air film will generate a lateral flow component from left to right.

[0042] Correction action: This lateral airflow acts on the lower surface of the decorative paper through fluid viscosity, generating a uniformly distributed lateral fluid shear force. This force smoothly pushes the decorative paper to the right, thereby correcting the left deviation error.

[0043] S304: The controller employs optimized control logic to ensure that the paper does not vibrate or get damaged during high-speed web alignment. The controller is based on the offset. The magnitude, rate of change (velocity), and cumulative amount are used to calculate the required differential pressure correction value using proportional (P), integral (I), and differential (D) algorithms. (The faster the offset, the more rapid the differential pressure adjustment; the smaller the offset, the gentler the differential pressure adjustment.)

[0044] Considering that decorative paper is usually thin, excessive pressure difference between the left and right sides can easily cause the paper to collapse on the low-pressure side or arch at the junction. Therefore, the controller has a preset safety limit logic: correcting the pressure value. Strictly limited to basic pressure of Within.

[0045] In this embodiment, the pneumatic differential pressure correction method used has a response lag that mainly depends on the action time of the air valve and the transmission speed of the air wave. The overall system response time can be controlled within the range of 20ms-50ms. In contrast, traditional servo motor-driven mechanical frame movement typically requires 200ms-500ms. This order-of-magnitude speed improvement allows this system to easily handle high-frequency deviation problems in high-speed cutting at speeds above 300mm / min.

[0046] S4: A negative pressure dust collection groove is set in the transition area between the stabilizing air plate and the correcting air plate. The high-speed airflow overflowing from the air plate in steps S1 and S3 blows the free dust on the surface of the decorative paper, and the dust-laden airflow is sucked away through the negative pressure dust collection groove. The specific implementation process is as follows: Physical layout and transition zone design: This embodiment cleverly utilizes the physical gap between the first-stage stabilizing air plate (S1) and the second-stage correcting air plate (S3). Below this gap, a negative pressure dust collection channel spanning the entire width of the decorative paper is provided.

[0047] Gap size: The physical gap width between the two air plates is set to 20mm-40mm.

[0048] The high-speed movement of decorative paper (an insulator) and friction with the air can accumulate static electricity of up to several thousand volts, causing paper dust to adhere firmly to the paper surface, which is difficult to remove by wind alone. Therefore, a high-voltage ion generator is integrated and installed on the inlet edge of the negative pressure dust collection tank.

[0049] The ion generator produces a high-concentration cloud of positive and negative ions that covers the surface of the paper tape. The instant the paper tape passes through this area, the electrostatic charge on the surface is neutralized, causing the electrostatic adsorption between the paper dust and the paper base to fail, thus converting the "sticky dust" into "free dust".

[0050] Instead of requiring additional high-pressure air nozzles, dust removal is achieved directly using the "exhaust gas" overflowing from S1 and S3: the overflow airflow from the tail of the S1 stabilizing air plate and the overflow airflow from the head of the S3 correcting air plate collide and converge at the gap in between. This colliding airflow creates strong local micro-turbulence on the lower surface of the paper tape. The free dust particles, which have just been destaticated, easily detach from the paper surface and become suspended under the scouring of the turbulent airflow. The negative pressure dust collection tank below is connected to a high-pressure centrifugal fan, generating 1500pa-2500pa to quickly extract the aforementioned turbulent gas carrying dust and completely remove it from the system.

[0051] To prevent the strong negative pressure from sucking thin decorative paper into the suction slot, causing scratches or tears, the suction slot opening has a special aerodynamic design: Venturi effect avoidance: The notch is not a right angle edge, but has a radius of curvature. The surface features a smooth, curved guide surface. This curved surface utilizes the Coanda effect to guide airflow smoothly into the groove, rather than through vertical suction. This allows the paper tape to maintain a suspension height of approximately 0.3mm as it passes above the groove opening, achieving "zero-contact dust removal." Even with fluctuations in negative pressure, the curved edge avoids sharp contact, maximizing the protection of the decorative paper's delicate printing layers.

[0052] S5: The decorative paper after S3 correction and reset is directly fed into the slitting knife group while maintaining the air-float rigid support. After longitudinal slitting, it is wound up through the rewinding unit. The specific implementation process is as follows: In traditional slitting machines, the alignment device is often a considerable distance (e.g., over 300mm) from the blade assembly; this suspended paper strip is called the "free span." At high speeds, the paper strip within this free span is highly susceptible to secondary drift or vibration. This embodiment achieves "zero-gap" slitting through a compact physical structure design: Cantilever extension: The outlet end of the second-stage correction air plate is designed as a wedge-shaped cantilever structure, which extends directly to the front of the biting point of the slitting blade assembly.

[0053] Distance Limitation: The horizontal distance between the end edge of the air plate and the cutting edge of the slitting blade is strictly controlled within... .

[0054] The slitting blade assembly adopts a shearing structure of "active lower blade + pneumatic upper blade": Bottom blade shaft: This is the active drive shaft, and its surface linear speed is set to be slightly higher than the running speed of the decorative paper.

[0055] Upper blade (circular blade): Employs a pneumatic clamping method, precisely controlling the lateral bonding force between the upper and lower blades by adjusting the air pressure. Considering the brittle nature of decorative paper, the bonding force is controlled within... .

[0056] During the production of decorative paper base paper, slight differences in transverse thickness are inevitable (e.g., thicker in the middle and thinner at the edges). If ordinary expansion shafts are used for winding, the diameter of thicker sub-rolls increases rapidly, resulting in a tighter winding; while the diameter of thinner sub-rolls increases slowly, resulting in a looser winding or even misalignment. To solve this problem, this embodiment employs a staggered dual-station differential shaft in the winding stage: Structural principle: The rotational speed of the slip differential spindle is always set higher than the speed required for the fastest roll diameter. Multiple independent friction rings are fitted on the spindle, each bearing one take-up paper core.

[0057] Automatic tension compensation: The system controls the frictional torque between the mandrel and the friction ring by adjusting the air bladder pressure inside the slip shaft. Regardless of the diameter of each roll (i.e., regardless of paper thickness), the friction ring will generate a corresponding "slipping" motion.

[0058] Staggered winding: Adjacent slit rolls are guided to the upper and lower winding shafts respectively, avoiding problems such as paper roll end face biting or sticking caused by too small slitting gap.

[0059] Ultimately, this system achieved the following accuracy indicators at a production speed of 300mm / min-500m / min: Cutting width tolerance: ; Evenness of the winding end face: Finished product surface quality: no scratches, no wrinkles, and no static electricity attracting dust.

[0060] The above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions will not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A high-speed, precise slitting process for decorative paper based on dual-air plate alignment, characterized in that, Includes the following steps: S1: The decorative paper to be cut is introduced into the first-stage stabilizing air plate area with a set tension. Constant pressure airflow is injected through the micropores distributed on the surface of the stabilizing air plate to form a continuous supporting air film on the lower surface of the decorative paper. The fluid adhesion effect is used to adsorb the decorative paper and suppress its longitudinal flutter during high-speed transmission. S2: Using a vision detection unit located downstream of the stabilizing air plate, the edge position signal or printed mark line signal of the decorative paper is collected in real time, and the collected signal is transmitted to the controller. The controller calculates the current lateral offset and offset direction of the decorative paper in combination with the preset reference position. S3: The decorative paper enters the second-stage correction air plate area along the transport path. The correction air plate is physically divided into a left air chamber and a right air chamber in the lateral width direction. The controller dynamically adjusts the air supply pressure ratio between the left air chamber and the right air chamber through an electric proportional valve according to the lateral offset calculated in step S2. An asymmetric lateral pressure gradient is constructed on the bottom surface of the decorative paper. The lateral fluid shear force generated by this pressure gradient drives the decorative paper to perform contactless reset to the opposite side of the offset direction. S4: A negative pressure dust collection groove is set in the transition area between the stabilizing air plate and the correcting air plate. The high-speed airflow overflowing from the air plate in steps S1 and S3 blows the free dust on the surface of the decorative paper, and the dust-laden airflow is sucked away through the negative pressure dust collection groove. S5: The decorative paper, after being corrected and reset by S3, is directly fed into the slitting knife group while maintaining the air-float rigid support. After longitudinal slitting, it is wound up by the rewinding unit.

2. The high-speed and precise slitting process for decorative paper based on dual-air plate alignment according to claim 1, characterized in that, In step S1, the surface configuration of the stabilizing air plate is a large-radius convex arc surface along the running direction of the decorative paper. The micropores are distributed in an alternating array on the convex arc surface, and the axis of each micropore is inclined towards the running direction of the decorative paper with an angle of 30° to 60°. The inclined jet airflow generates a viscous traction force along the running direction on the lower surface of the decorative paper to tighten the paper strip.

3. The high-speed and precise slitting process for decorative paper based on dual-air plate alignment according to claim 2, characterized in that, The stabilizing air plate has a double-layer flow equalization chamber inside. The external air source enters the second chamber after being buffered by the first chamber and rectified by the flow equalization plate, and is then ejected through the microholes to ensure that the static pressure fluctuation range of the formed air film is controlled within ±2%.

4. The high-speed and precise slitting process for decorative paper based on dual-air plate alignment according to claim 3, characterized in that, In step S2, the visual detection unit uses a high-speed linear CCD camera with a sampling frequency of not less than 10kHz in conjunction with a parallel backlight. When calculating the lateral offset, the controller first uses a sub-pixel edge detection algorithm to lock the edge coordinates of the decorative paper based on the pixel grayscale gradient. Then, it processes the continuously acquired edge coordinate signals through a moving average filtering algorithm or a Kalman filtering algorithm to remove random noise caused by high-frequency paper flutter and extract only the low-frequency component that represents the deviation of the actual running trajectory as the final lateral offset output to step S3.

5. The high-speed and precise slitting process for decorative paper based on dual-air plate alignment according to claim 4, characterized in that, In step S3, The controller employs a PID closed-loop control algorithm and pre-sets a basic buoyancy pressure value that can maintain the stable suspension of the decorative paper. ; Upon receiving a lateral offset signal, the controller simultaneously controls the air pressure in both the left and right air chambers in differential adjustment mode, raising the pressure in one chamber to a certain level and lowering the pressure in the other chamber to a certain level. ,in This is the corrected pressure value calculated based on the offset. The controller has a preset maximum differential pressure threshold to limit Not exceeding the basic buoyancy pressure value of This is to prevent the decorative paper from arching or wrinkling on the surface of the correction air plate due to excessive lateral pressure gradient.

6. The high-speed and precise slitting process for decorative paper based on dual-air plate alignment according to claim 5, characterized in that, In step S4, the negative pressure suction groove spans the full width of the decorative paper, and the two sides of the groove opening are provided with smooth guide arc surfaces with a curvature radius of 2mm to 5mm to prevent the decorative paper from scratching the groove opening under negative pressure. A high-voltage ion generator is integrated at the entrance of the negative pressure dust collection tank. It emits positive and negative ion beams onto the surface of the decorative paper to eliminate surface static charge, causing the adsorbed dust on the surface of the decorative paper to dissociate. Subsequently, the dust is drawn into the negative pressure dust collection tank by the converging airflow overflowing from the stabilizing air plate and the correcting air plate, forming a three-stage dust removal mechanism of static electricity removal, airflow stripping, and negative pressure collection.

7. The high-speed and precise slitting process for decorative paper based on dual-air plate alignment according to claim 6, characterized in that, In step S5, The slitting blade assembly adopts a shearing structure, including an actively driven lower blade shaft and a pneumatically clamped upper circular blade; The outlet end of the correction air plate extends to a position less than 50mm away from the biting point of the slitting blade group, minimizing the free span of the decorative paper after it leaves the air support. After being slit, multiple decorative paper strips are wound up by a staggered dual-station differential shaft. The friction ring assembly inside the differential shaft automatically compensates for tension differences based on the changes in the roll diameter of each paper strip, ensuring that the end face uniformity error of all slit sub-rolls is controlled within ±0.2mm.

8. A high-speed, precise slitting system for decorative paper based on dual-air plate alignment, characterized in that, The following units are arranged sequentially along the direction of decorative paper transport: an air-float flow stabilizing unit, including a first-stage flow stabilizing air plate, the surface of which is distributed with a micro-pore array and connected to a constant pressure air source, used to establish a stable supporting air film and eliminate longitudinal flutter before the decorative paper enters the slitting zone; A visual inspection unit, located downstream of the air-float stabilizing unit, includes a high-frequency linear array camera and a matching light source, and is configured to acquire the edge position or marking line signal of the decorative paper in real time. The differential pressure air float correction unit includes a second-stage correction air plate, an electro-proportional valve group, and a central controller; the correction air plate is physically divided into a left air chamber and a right air chamber that are not connected to each other in the lateral width direction, and the electro-proportional valve group independently controls the intake pressure of the left air chamber and the right air chamber respectively. The negative pressure dust removal unit is arranged in the physical gap between the air flotation flow stabilization unit and the differential pressure air flotation correction unit. It includes a dust suction groove spanning the width of the paper web and a negative pressure generating device for suctioning dust from the surface of the decorative paper. The zero-gap slitting unit is arranged immediately at the end of the differential pressure air flotation correction unit, and includes a slitting blade assembly and a winding mechanism. The central controller is electrically connected to the vision detection unit and the electro-proportional valve group, and is configured to execute the following control logic: receive the lateral offset signal fed back by the vision detection unit, calculate the correction value through the PID algorithm, and drive the electro-proportional valve group to establish a pressure difference corresponding to the offset between the left and right air chambers, thereby constructing a fluid pressure gradient on the surface of the correction air plate to drive the decorative paper to lateral reset.

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