A UV coating apparatus

Abstract

This invention discloses a UV coating equipment, relating to the field of coating equipment technology. The equipment includes a frame, a belt conveyor mechanism, a lamp assembly, two distance sensors, a material feeding mechanism, and a controller. The lamp assembly includes a central lamp, a left short lamp, and a right short lamp, arranged sequentially along the width of the sheet material and capable of independent start / stop. The central lamp is longer than each of the short lamps. The two short lamps are arranged coaxially with the central lamp, radially offset and partially overlapping axially. The irradiation direction is obliquely towards one side of the central lamp, ensuring that the irradiation areas of each lamp segment on the sheet surface are connected end-to-end without overlap, eliminating hidden seams at the segment joints. The material feeding mechanism includes feeding units located on both sides of the feed end of the belt conveyor mechanism. Each feeding unit has a push cylinder, a push plate, and an arc-shaped guide. The controller controls the start / stop of each lamp according to the width of the sheet material and drives the feeding units to push the sheet material into the irradiation area of ​​the lit lamp according to the lateral position of the sheet material, achieving energy-saving curing of narrow sheets and preventing sheet material deviation and incomplete curing.

Description

Technical Field

[0001] This invention relates to the field of coating equipment technology, and more specifically to a UV coating equipment. Background Technology

[0002] As the furniture and building materials industry shifts towards smaller batches and more diverse specifications in its orders, the same UV coating equipment needs to frequently cure boards with significant width variations. Existing UV coating systems, which illuminate the entire length of the lamp regardless of board width, have the following drawbacks: First, when the board width is significantly smaller than the lamp length, the portion of the lamp extending beyond the board width continues to irradiate, unnecessarily wasting energy and shortening the lamp's lifespan. Furthermore, excess UV light directly irradiates exposed parts of the conveyor mechanism and frame, accelerating the photoaging of non-metallic components such as conveyor belts and seals, and shortening equipment maintenance cycles. Second, if the lamp is simply segmented and spliced ​​along the same axis, the ends of the lamps contain non-light-emitting sections such as electrode mounting areas or structural edge areas. This can lead to problems at the joints between adjacent lamp segments. This will create a dark strip extending along the conveying direction. When the board passes through the dark strip, the coating in this transverse strip area will have insufficient irradiation dose, resulting in poor local curing and affecting the consistency of the coating performance. Thirdly, the board is prone to transverse deviation during belt conveying due to factors such as conveyor belt deviation and feed skew. When the lamp group is illuminated according to the width of the board, some areas of the board that has deviated will move out of the illumination range of the lamp tube, causing the coating on the edge of the board to be under-cured. However, the existing equipment lacks an actuator to automatically correct the transverse position of the board, and can only rely on frequent manual adjustments by the operator.

[0003] Chinese patent document CN109955587A discloses a UV-LED drying device and method for intelligently identifying the width of printed materials. It divides the UV-LED lamps into at least two groups, each group of which can be turned on or off independently. A width sensor identifies the width of the printed material to be dried, and a PLC controller controls the opening and closing of each group of lamps based on the identification results, thereby reducing energy consumption. Chinese patent document CN102574149A discloses a multi-row scalable LED-UV module, which assembles light-emitting diodes onto segments of various lengths. These segments can be spliced ​​together to form a UV light module of the required length, facilitating the scaling of the light source length and the rapid replacement of damaged segments.

[0004] While the existing solutions described above achieve adjustment of the light source illumination range or total length according to the width of the workpiece, two problems remain unresolved: First, none of them address the connection of the light curtains at the joints of segmented light sources, so the dark band problem caused by the non-light-emitting sections at the ends persists when segments or light groups are spliced ​​along the same axis. Second, none of them are equipped with an actuator for lateral correction of the workpiece. When the light source illumination range narrows according to the width of the workpiece, if the workpiece deviates during transport, it will move out of the illumination area, causing incomplete curing, making it difficult to balance energy saving and curing quality. Therefore, providing a UV coating equipment that can both reduce energy consumption by illuminating the lamps in sections according to the width of the workpiece, eliminate the dark band at the joints, and ensure that the misaligned workpiece is always within the illumination area of ​​the lamps is a technical problem that urgently needs to be solved in this field. Summary of the Invention

[0005] The technical problem to be solved by the present invention is that: the full-length lamp tubes of existing UV coating equipment are constantly lit, resulting in high energy consumption and lamp life loss when curing narrow plates, and the excess UV light accelerates the aging of the conveying mechanism and frame; after the lamp tubes are segmented and coaxially spliced, dark bands are formed at the splicing points along the conveying direction, causing poor local curing of the coating on the board; after the lamp group is lit according to the width of the board, the lateral deviation of the board will cause some areas to move out of the irradiation range, resulting in edge uncuring, and the existing equipment lacks an execution mechanism for lateral deviation correction of the board.

[0006] To solve the above-mentioned technical problems, the present invention adopts the following technical solution: A UV coating equipment, comprising: frame; The conveying mechanism, mounted on the frame, is used to convey the sheet metal. The lamp assembly is located above the conveying mechanism and includes a left short lamp tube, a middle lamp tube, and a right short lamp tube arranged sequentially along the width of the plate and can be started and stopped independently. The middle lamp tube is longer than the left and right short lamp tubes. The left and right short lamp tubes are not coaxial with the middle lamp tube and are radially offset and axially overlapped. Their illumination direction is oblique to one side of the middle lamp tube. The first and second distance sensors are respectively located on both sides of the feed end of the conveying mechanism to detect the width and lateral position of the plate. The feeding mechanism includes a left feeding unit and a right feeding unit located on both sides of the feeding end of the conveying mechanism. Both the left feeding unit and the right feeding unit include a push cylinder and a push plate. The cylinder body of the push cylinder is fixed to the frame, and the push plate is fixed to the end of the piston rod of the push cylinder. The free end of the push plate is provided with an arc-shaped guide. The controller is electrically connected to the lamp group, the first distance sensor, the second distance sensor, and the feeding mechanism. It controls the start and stop of each lamp according to the width of the board and drives the left feeding unit or the right feeding unit according to the lateral position of the board so that the board is located in the illumination area of ​​the lit lamp.

[0007] The lamp assembly also includes a middle lamp cover, a left lamp cover, and a right lamp cover. The middle lamp cover is located outside the middle lamp tube and illuminates the light from the middle lamp tube vertically downwards. The left lamp cover is located outside the left short lamp tube and illuminates the light from the left short lamp tube obliquely towards the middle lamp tube. The right lamp cover is located outside the right short lamp tube and illuminates the light from the right short lamp tube obliquely towards the middle lamp tube. The inner walls of the middle lamp cover, the left lamp cover, and the right lamp cover are all provided with reflective surfaces.

[0008] The axial overlap length between the left short tube and the middle tube is equal to the sum of the lengths of the non-light-emitting areas at the ends of the middle tube and the left short tube. The axial overlap length between the right short tube and the middle tube is equal to the sum of the lengths of the non-light-emitting areas at the ends of the middle tube and the right short tube. The light-emitting area of ​​each short tube extends beyond the splicing seam with the middle tube and fills in the non-light-emitting area at the end of the middle tube. The irradiation areas of each tube on the surface of the board are connected along the width direction of the board.

[0009] The angle between the light emission direction of the left lampshade and the vertical direction is 10 to 30 degrees, and the angle between the light emission direction of the right lampshade and the vertical direction is 10 to 30 degrees.

[0010] The middle section lamp, the left short lamp, and the right short lamp are all LED ultraviolet light strips. The light-emitting length of the middle section lamp accounts for 60% of the total light-emitting length of the lamp group, while the light-emitting lengths of the left short lamp and the right short lamp each account for 20% of the total light-emitting length of the lamp group.

[0011] The controller is also configured to: illuminate only the middle section lamp when the width of the board is less than the illumination width of the middle section lamp; illuminate the middle section lamp and either the left or right short lamp when the width of the board is greater than the illumination width of the middle section lamp and less than the sum of the illumination width of the middle section lamp and the illumination width of a short lamp; and illuminate the middle section lamp, the left short lamp, and the right short lamp when the width of the board is greater than the sum of the illumination width of the middle section lamp and the illumination width of a short lamp.

[0012] The left short tube, the middle tube, and the right short tube are each detachably mounted on the lamp holder beam via their respective independent lamp holders. The lamp holder beam is mounted on the top of the frame along the width of the plate. The lamp assembly also includes an independent power drive circuit that corresponds to each of the three tubes. If any tube is damaged, it can be replaced individually without disassembling the other tubes and the lamp holder beam.

[0013] The controller is also configured to: calculate the lateral offset of the board relative to the conveying baseline based on the detection values ​​of the first and second distance sensors; when the lateral offset is greater than a preset threshold, drive the feeding unit on the side where the board offset is located to move, and push the board towards the conveying baseline by the push plate until the edge of the board is aligned with the edge of the illuminated area of ​​the lamp tube.

[0014] The conveying mechanism is a belt conveyor, which includes a conveyor belt and a conveyor motor. The conveyor belt is wound between the driving roller and the driven roller, and the conveyor motor drives the driving roller to rotate. The extension speed of the piston rod of the push cylinder is matched with the conveying linear speed of the conveying mechanism, so that the plate can be pushed laterally during the conveying process.

[0015] Both the first and second ranging sensors are laser displacement sensors or photoelectric beam sensors. The detection optical axes of the first and second ranging sensors are perpendicular to the conveying direction of the plate and are respectively set towards the two side edges of the plate.

[0016] Compared with the prior art, the beneficial effects of the present invention are as follows: Firstly, the lamp assembly is divided into a middle section lamp tube and two short lamp tubes on both sides that can be started and stopped independently along the width of the board. The controller only lights up the lamp section required to cover the width of the board based on the width of the board measured by the distance sensor. When the narrow board is cured, the unlit lamp section does not consume power or generate ultraviolet radiation, which significantly reduces operating energy consumption, extends the service life of the lamp tube, and avoids photoaging damage to the conveying mechanism and frame caused by excess ultraviolet light.

[0017] Secondly, the short lamps on both sides are arranged off-axis from the middle lamp, with radial deviation and partial axial overlap. The light-emitting area of ​​each short lamp crosses the splicing seam to fill the corresponding non-light-emitting area of ​​the board strip at the end of the middle lamp, eliminating the dark seam formed at the splicing point of the segmented light source due to the non-light-emitting area at the end. At the same time, the irradiation direction is oblique to one side of the middle lamp and shaped by the lampshade, so that the irradiation area of ​​each segment of lamp on the board surface is just connected and does not overlap. The irradiance on the board surface is continuous and uniform along the width direction, with no dark seam incomplete curing and no over-curing of the joint caused by irradiation superposition.

[0018] Thirdly, the conveying mechanism has a first distance sensor and a second distance sensor on both sides of the feeding end, which can simultaneously obtain the width and lateral position information of the board. The material feeding mechanism includes a left feeding unit and a right feeding unit, which are located on both sides of the conveying mechanism and have a push cylinder, a push plate and an arc-shaped guide. When the board deviates, the controller drives the corresponding feeding unit to feed the board back into the illumination area of ​​the lit lamp tube, so that the light curtain that narrows according to width always completely covers the board surface during operation, eliminating edge curing failure caused by deviation and improving product yield.

[0019] Fourth, the controller automatically starts and stops the lamps and aligns the boards according to the width and lateral position of the boards. The entire process requires no operator intervention, adapts to continuous production of mixed boards of various specifications, and allows for continuous production without stopping the machine or changing lamps when switching specifications. This makes production organization flexible and reduces the intensity of manual labor.

[0020] Fifth, the three lamp sections are separately installed along the width of the board and do not overlap. Each lamp is detachably installed on the lamp holder beam through an independent lamp holder and connected to an independent power drive circuit. If any lamp section is damaged, it can be replaced individually without disassembling the other lamps and the lamp holder beam, which greatly reduces spare parts costs and downtime. At the same time, each lamp is installed independently and does not overlap. After replacement, it is only necessary to install the lamp in place to maintain the connection relationship of the original illumination area. There is no need to readjust the installation position and illumination angle of the other lamps, nor is it necessary to recalibrate the light curtain coverage of the entire lamp. Attached Figure Description

[0021] To more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings used in the following description of the embodiments will be briefly introduced. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0022] Figure 1 This is a front view schematic diagram of the overall structure of a UV coating equipment according to the present invention; Figure 2 This is a top view of the lamp assembly arrangement in this invention; Figure 3 This is a schematic diagram of the lamp assembly illuminating the plate in this invention; Figure 4 This is a schematic diagram showing the arrangement of the feeding mechanism and the ranging sensor at the feeding end of the conveying mechanism in this invention.

[0023] The labels in the figures are explained as follows: 1 is the frame; 2 is the conveying mechanism; 3 is the lamp assembly; 31 is the middle section lamp tube; 311 is the middle section lamp cover; 32 is the left short lamp tube; 321 is the left lamp cover; 33 is the right short lamp tube; 331 is the right lamp cover; 34 is the lamp holder crossbeam; 41 is the first distance sensor; 42 is the second distance sensor; 5 is the feeding mechanism; 51 is the left feeding unit; 511 is the left push cylinder; 512 is the left push plate; 513 is the left arc-shaped guide; 52 is the right feeding unit; 521 is the right push cylinder; 522 is the right push plate; 523 is the right arc-shaped guide; 6 is the controller; 7 is the sheet material; 8 is the conveying direction. Detailed Implementation

[0024] To further illustrate the technical means and effects of the present invention in achieving its intended purpose, the following detailed description of the specific implementation methods, structures, features, and effects of the present invention, in conjunction with the accompanying drawings and preferred embodiments, is provided below.

[0025] Example 1

[0026] This embodiment describes the overall structure of a UV coating equipment. For example... Figure 1 As shown, the equipment includes a frame 1, a conveying mechanism 2, a light group 3, a first distance sensor 41, a second distance sensor 42, a feeding mechanism 5, and a controller 6.

[0027] The frame 1 is a frame structure welded from structural steel, used to support the various components of the equipment. The conveying mechanism 2 is mounted on the frame 1 and is a belt conveyor mechanism, including a conveyor belt, a drive roller, a driven roller, and a conveyor motor. The drive roller and the driven roller are rotatably supported at both ends of the frame 1 along the conveying direction 8, respectively. The conveyor belt is wound between the drive roller and the driven roller and is tensioned. The upper edge of the conveyor belt extends horizontally, forming a conveying plane for carrying and conveying the plate 7. The conveyor motor is fixedly mounted on the frame 1 and is connected to the drive roller via a reduction transmission mechanism to drive the conveyor belt to circulate, so that the plate 7 moves along the conveying direction 8.

[0028] The lamp assembly 3 is positioned above the conveying mechanism 2 and includes a middle lamp tube 31, a left short lamp tube 32, and a right short lamp tube 33 arranged sequentially along the width direction of the plate 7. All three lamp tubes are elongated and span across the top of the conveying mechanism 2, with their axial direction perpendicular to the conveying direction 8. The middle lamp tube 31 is located in the middle of the equipment's width direction, and its length is greater than both the length of the left short lamp tube 32 and the length of the right short lamp tube 33. The left short lamp tube 32 is located to the left of the middle lamp tube 31, and the right short lamp tube 33 is located to the right of the middle lamp tube 31.

[0029] The aforementioned lamps are detachably mounted on lamp holder beams 34 via their respective independent lamp holders. Lamp holder beams 34 are mounted on top of the frame 1 along the width of the plate 7. The mounting positions of each lamp on the lamp holder beams 34 are independent, allowing for the removal or installation of any lamp without disassembling the remaining lamps or lamp holder beams 34. Each segment of the lamp is equipped with an independent power drive circuit, allowing for individual lighting, extinguishing, or power adjustment. The left short lamp 32, the middle lamp 31, and the right short lamp 33 all utilize LED ultraviolet light strips. Several LED ultraviolet beads are arranged along the length of the light strip. The peak wavelength of the beads can be selected from 365 nm, 385 nm, 395 nm, or 405 nm, and the selection is based on the absorption peak of the photoinitiator in the UV coating. In this embodiment, the peak wavelength of the beads is 395 nm. The LED ultraviolet light strips can achieve instantaneous start and stop without preheating, making them suitable for frequent segmented switching conditions.

[0030] like Figure 4As shown, the first ranging sensor 41 and the second ranging sensor 42 are respectively located on both sides of the feed end of the conveying mechanism 2, and are fixedly installed on the frame 1 or the frame of the conveying mechanism 2. Their installation height is higher than the surface of the upper side belt of the conveyor belt. The detection optical axis is perpendicular to the conveying direction 8 of the plate 7 and is respectively directed towards the two side edges of the plate 7. It is used to detect the distance between the two side edges of the plate 7 and the sensor, and then calculate the width of the plate 7 and the lateral position of the plate 7 in the conveying plane. In this embodiment, both the first ranging sensor 41 and the second ranging sensor 42 are laser displacement sensors, which have fast response speed and strong resistance to ambient light interference.

[0031] The feeding mechanism 5 is located at the feeding end of the conveying mechanism 2, and includes a left feeding unit 51 and a right feeding unit 52, which are respectively located on both sides of the conveying mechanism 2. The left feeding unit 51 includes a left push cylinder 511, a left push plate 512, and a left arc-shaped guide part 513. The cylinder body of the left push cylinder 511 is fixedly connected to the left side of the frame 1. The piston rod of the left push cylinder 511 extends and retracts along the width direction of the plate 7. The left push plate 512 is fixedly connected to the end of the piston rod of the left push cylinder 511. The left push plate 512 is a vertical plate, and its plate surface is parallel to the conveying direction 8 of the plate 7. The front end of the left push plate 512 facing the material direction of the plate 7 bends and extends outward to form the left arc-shaped guide part 513. The inner side of the left arc-shaped guide part 513 is a smooth arc surface, which is used to guide the contact with the side edge arc surface of the plate 7. The right feeding unit 52 includes a right push cylinder 521, a right push plate 522, and a right arc-shaped guide part 523. Their composition and connection relationship are symmetrical with the left feeding unit 51 along the centerline of the equipment width direction. Both the left push cylinder 511 and the right push cylinder 521 can be pneumatic cylinders or servo electric cylinders. In this embodiment, pneumatic cylinders are used. The piston rod extends and retracts by controlling the air supply through a solenoid valve. The extension speed is adjusted by a throttle valve.

[0032] The controller 6, employing a programmable logic controller (PLC) and a touchscreen, forms a human-machine interface and is installed in the electrical control cabinet on one side of the rack 1. The controller 6 is electrically connected to the power drive circuits of each section of the lamps in the lamp group 3, the first distance sensor 41, the second distance sensor 42, the solenoid valves of the left push cylinder 511 and the right push cylinder 521, and the conveyor motor. Based on the detection signals from the first distance sensor 41 and the second distance sensor 42, the controller 6 calculates the width and lateral position of the board 7, and accordingly controls the start and stop of the middle section lamp 31, the left short lamp 32, and the right short lamp 33. When the board 7 deviates from its designated position, the controller 6 drives the left material-shifting unit 51 or the right material-shifting unit 52 to move the board 7 laterally into the irradiation area of ​​the lit lamp. Based on this structure, the UV coating equipment of this embodiment can automatically adapt to the curing of boards of different widths without replacing lamps or requiring manual intervention, achieving a linkage between energy-saving curing and anti-deviation curing.

[0033] Example 2

[0034] This embodiment further explains the lampshade structure of lamp group 3 based on embodiment 1. For example... Figure 2 and Figure 3 As shown, the lamp assembly 3 also includes a middle lampshade 311, a left lampshade 321, and a right lampshade 331, with the three lampshades respectively covering the outer side of the corresponding lamp tubes. The middle lampshade 311 covers the outer side of the middle lamp tube 31, and its cross-section is a downward-facing groove with the groove opening vertically downward. The ultraviolet light emitted by the middle lamp tube 31 is reflected by the inner wall of the middle lampshade 311 and shines vertically downward onto the surface of the board 7. The left lampshade 321 covers the outer side of the left short lamp tube 32, and its groove opening faces obliquely downward and is biased towards the middle lamp tube 31, so that the ultraviolet light emitted by the left short lamp tube 32 shines obliquely towards the middle lamp tube 31. The right lampshade 331 covers the outer side of the right short lamp tube 33, and its groove opening faces obliquely downward and is biased towards the middle lamp tube 31, so that the ultraviolet light emitted by the right short lamp tube 33 shines obliquely towards the middle lamp tube 31. The inner walls of the middle lampshade 311, the left lampshade 321, and the right lampshade 331 are all provided with reflective surfaces. These reflective surfaces can be made of mirrored aluminum plates or aluminized reflective plates, and are used to converge and reflect the ultraviolet light scattered by the lamp tubes to the surface of the plate 7, thereby improving the utilization efficiency of ultraviolet light. Specifically, heat dissipation gaps are provided between the middle lampshade 311 and the middle lamp tube 31, between the left lampshade 321 and the left short lamp tube 32, and between the right lampshade 331 and the right short lamp tube 33. Ventilation holes are provided at the ends of the lampshades to cooperate with the original exhaust system of the equipment for air cooling of the lamp tubes. Based on the above scheme, the middle section lamp tube 31 vertically illuminates and covers the middle strip area of ​​the board 7, while the short lamp tubes on both sides illuminate obliquely. The edge of their illumination area is exactly connected with the edge of the illumination area of ​​the middle section lamp tube 31. The illumination areas formed by the three lamp tubes on the surface of the board 7 are connected end to end and do not overlap with each other. There are no hidden seams or radiation overlap. At the same time, the reflective surface of the lamp cover recovers and utilizes the side-dissipated ultraviolet light, thus improving the uniformity of irradiation and the light energy utilization rate simultaneously.

[0035] Example 3

[0036] This embodiment, based on Embodiment 1, explains the selection of the axial overlap amount of adjacent lamp tubes. For example... Figure 2 As described above, the left short lamp tube 32 and the middle lamp tube 31 are arranged in an axially staggered manner. The axial overlap length of the left short lamp tube 32 and the middle lamp tube 31 is equal to the sum of the lengths of the non-light-emitting areas at the ends of the middle lamp tube 31 and the left short lamp tube 32. Similarly, the axial overlap length of the right short lamp tube 33 and the middle lamp tube 31 is equal to the sum of the lengths of the non-light-emitting areas at the ends of the middle lamp tube 31 and the right short lamp tube 33. Here, the non-light-emitting area at the ends refers to the edge section at both ends of the lamp strip where LED beads cannot be arranged due to the reserved space for installing end caps, wiring terminals, and electrode welding. Its length is determined by the structure of the lamp strip.

[0037] Specifically, the right edge of the luminous area of ​​the left short lamp tube 32 and the left edge of the luminous area of ​​the middle lamp tube 31 are precisely connected on the surface of the board 7. The two lamp tubes will not simultaneously irradiate the same transverse strip on the surface of the board 7, thus there is no irradiation superposition. Based on the above scheme, even if there is a non-luminous area at the end of a certain lamp tube, the luminous area of ​​the adjacent short lamp tube has already filled it across the splicing seam. The irradiation dose at any transverse position on the surface of the board 7 just meets the curing requirements and will not be excessive due to simultaneous irradiation by multiple lamps. There are no dark seams or over-irradiation at the splicing points of the segmented light sources, and the thickness and cross-linking degree of the cured film are highly consistent along the width direction.

[0038] Example 4

[0039] This embodiment, based on Embodiment 2, explains the selection of the lampshade tilt angle. For example... Figure 3 As shown, the angle between the light-emitting direction of the left lampshade 321 and the vertical direction, and the angle between the light-emitting direction of the right lampshade 331 and the vertical direction, are both within the range of 10 to 30 degrees. This angle is reflected by the tilt direction of the lampshade slot plane. In this embodiment, the angle between the light-emitting direction of the left lampshade 321 and the vertical direction of the right lampshade 331 is 20 degrees. The size of the tilt angle is determined based on the distance from the lower edge of the lampshade's light outlet to the surface of the plate 7 and the connection position of each irradiation area on the surface of the plate 7: if the tilt angle is too small, the oblique light of the short lamp tube will fall to one side, leaving a dark gap between the irradiation area of ​​the short lamp tube and the irradiation area of ​​the middle lamp tube 31; if the tilt angle is too large, the oblique light of the short lamp tube will cross the connection position and enter the irradiation area of ​​the middle lamp tube 31, causing irradiation superposition. Based on the above scheme, while the short lamps on both sides effectively cover their own width area, their irradiation area is connected end to end with the irradiation area of ​​the middle lamp 31. The illuminance loss caused by oblique radiation is within an acceptable range, and the curing dosage and the continuity of the light curtain are taken into account.

[0040] Example 5

[0041] This embodiment, based on Embodiment 1, explains the lamp tube length ratio and selection for lamp group 3. The luminous length of the middle section lamp tube 31 accounts for 60% of the total luminous length of lamp group 3, while the luminous lengths of the left short lamp tube 32 and the right short lamp tube 33 each account for 20% of the total luminous length of lamp group 3. That is, when the total luminous length of lamp group 3 is L, the luminous length of the middle section lamp tube 31 is 0.6L, and the luminous lengths of the left short lamp tube 32 and the right short lamp tube 33 are each 0.2L. All three lamp tubes are LED UV lamp strips, using water cooling or air cooling for heat dissipation. The power density of the lamp strips is configured at 60 watts per centimeter to 120 watts per centimeter. The specific power is determined based on the curing dosage requirements of the UV coating (usually 800 millijoules per square centimeter to 1200 millijoules per square centimeter) and the conveyor line speed. The illumination area of ​​the middle section lamp tube 31 covers approximately 60% of the board width. This range corresponds to the most common medium-width specifications in furniture and decorative board production. For narrow boards (width less than 0.6L), only the middle section lamp tube 31 needs to be lit during curing, at which point the lamp group 3 consumes only about 60% of the total power, resulting in significant energy savings. When the board width is greater than 0.6L but less than 0.8L, the middle section lamp tube 31 and the corresponding short lamp tube on one side are lit. When the board width is greater than 0.8L, all three sections of lamp tubes are lit, covering all board specifications within the rated processing width of the equipment. The total width of the illumination area of ​​the lamp group 3 is designed based on the maximum rated processing board width of the equipment. The width of the boards 7 entering the equipment is less than the total width of the illumination area of ​​the lamp group 3, and there is no situation where the width of the board 7 is greater than the total width of the illumination area of ​​the lamp group 3. Based on the above scheme, the 60% plus 20% plus 20% ratio enables the low-energy-consumption condition of "only lighting the middle section of the lamp" to cover most specifications in production, maximizing energy-saving benefits. At the same time, the start-stop combination of the three sections of the lamp can cover all commonly used specifications from narrow to wide panels.

[0042] Example 6

[0043] This embodiment describes the lamp start / stop control logic of controller 6. After power-on, controller 6 continuously collects the detection values ​​of the first ranging sensor 41 and the second ranging sensor 42. When the board 7 enters the feed end of the conveying mechanism 2 and passes the detection optical axis of the ranging sensor, the side edge of the board 7 blocks the light path, and the sensor reading changes. Controller 6 calculates the width of board 7 and the lateral position of board 7 in the conveying plane based on the time of change of the readings of the first ranging sensor 41 and the second ranging sensor 42 and the difference in readings. Before the front end of the board 7 reaches below the lamp group 3, the controller 6 makes a decision on the lamp start / stop combination: when the width of the board 7 is less than the illumination width of the middle lamp 31, only the middle lamp 31 is lit; when the width of the board 7 is greater than the illumination width of the middle lamp 31 but less than the sum of the illumination width of the middle lamp 31 and the illumination width of a short lamp, the middle lamp 31 and the short lamp are lit; when the width of the board 7 is greater than the sum of the illumination width of the middle lamp 31 and the illumination width of a short lamp, the middle lamp 31, the left short lamp 32, and the right short lamp 33 are lit. The width of the board 7 entering this equipment for processing is less than the total width of the illumination area of ​​the lamp group 3, which is a prerequisite for the normal operation of the equipment; if the ranging sensor detects that the width of the board 7 is greater than the total width of the illumination area of ​​the lamp group 3, the controller 6 determines that the board 7 exceeds the processing range of the equipment, controls the conveyor motor to stop and outputs an over-width alarm, and at this time, no lamp segment is lit to prevent the over-width board from being partially cured and becoming a waste product. After each section of the LED tube is lit, its power is adjusted by the controller 6 according to the preset curing formula. The curing formula is pre-stored in the controller 6 based on the width of the board 7, the conveyor speed, and the type of coating. Specifically, the start-stop decision of the LED tube is completed before the front end of the board 7 enters the lighting area. The LED tubes light up instantly without delay, and the board 7 is fully irradiated as soon as it enters the lighting area. Based on the above scheme, the equipment achieves automatic matching between the lighting range of the LED tubes and the width of the board. When narrow boards are being cured, the unlit sections do not consume power or receive irradiation, which reduces energy consumption and avoids damage to the conveyor mechanism from excess ultraviolet light. At the same time, when multiple specifications of boards are produced continuously on a mixed production line, there is no need to stop the machine to adjust the LED tubes, and the production efficiency is not affected.

[0044] Example 7

[0045] This embodiment explains the logic of how the controller 6 drives the feeding mechanism 5 to laterally align the sheet material. The controller 6 calculates the distance between the two edges of the sheet material 7 and their respective sensors based on the detection values ​​from the first distance sensor 41 and the second distance sensor 42, thereby obtaining the lateral offset of the sheet material 7 relative to the conveying reference line. The conveying reference line is a pre-set lateral position reference that the sheet material 7 should maintain in the conveying plane, corresponding to the center or edge position of the illuminated area along the width direction of the sheet material 7, and can be set by the operator via a touchscreen. When the lateral offset of the plate 7 is less than the preset threshold, it indicates that the plate 7 is still within the illumination area of ​​the lit lamp, and the controller 6 does not drive the feeding mechanism 5 to operate, and the plate 7 moves normally with the conveyor mechanism 2. When the lateral offset of the plate 7 is greater than the preset threshold, it indicates that the plate 7 has a tendency to move out of the illumination area of ​​the lit lamp, and the controller 6 drives the feeding unit on the side of the offset direction of the plate 7 to operate, that is, when the plate 7 offsets to the left, the left feeding unit 51 is driven, and when the plate 7 offsets to the right, the right feeding unit 52 is driven. The piston rod of the corresponding push cylinder extends, and the arc-shaped guide part at the front end of the push plate contacts the arc surface of the side edge of the plate 7, pushing the side edge of the plate 7 to move towards the conveyor baseline. The plate 7 is pushed laterally while moving forward with the conveyor belt until the edge of the plate 7 is aligned with the edge of the illumination area of ​​the lit lamp, and the controller 6 controls the piston rod of the push cylinder to retract back to its original position. The size of the preset threshold is determined according to the margin of the illumination area of ​​the lit lamp relative to the width direction of the plate 7. Based on the above scheme, the feeding mechanism 5 only operates when the board 7 shows a tendency to deviate. The operating stroke is small and the frequency is low, so it will not interfere with the normal conveying of the board 7. At the same time, it ensures that the board 7 is always completely within the illumination area of ​​the lit lamp tube under the narrowing light curtain condition, thus eliminating edge curing failure caused by deviation.

[0046] Example 8

[0047] This embodiment explains the matching relationship between the material feeding action and the conveying speed. The conveying motor in the conveying mechanism 2 is a variable frequency motor, and its speed is controlled by the controller 6 via the frequency converter, thereby adjusting the speed of the drive roller and the conveying linear speed of the conveyor belt. The piston rod extension speed of the left push cylinder 511 and the right push cylinder 521 is adjusted by the throttle valve to match the piston rod extension speed with the conveying linear speed of the conveying mechanism 2. That is, the time required for the plate 7 to be laterally pushed by the push plate to complete the correction amount is less than the time for the plate 7 to pass through the feeding zone, ensuring that the plate 7 smoothly completes the lateral pushing during the conveying process without slipping or deflecting on the conveyor belt.

[0048] Based on the above scheme, the feeding process and the conveying process are carried out in coordination. The sheet 7 can be corrected laterally without stopping. The equipment maintains a continuous production cycle. The arc-shaped guide part's arc-shaped contact structure reduces the risk of damage to the sheet edge during feeding. It is suitable for sheets that have been coated with UV primer or topcoat and will not damage the coating appearance.

[0049] Example 9

[0050] This embodiment describes the selection and installation of the first ranging sensor 41 and the second ranging sensor 42. Both the first ranging sensor 41 and the second ranging sensor 42 are laser displacement sensors, employing the triangular reflection laser ranging principle, with a range of 50 mm to 250 mm, a resolution of 0.1 mm, and a response frequency of not less than 1 kHz. The first ranging sensor 41 is installed on the left side of the frame 1, and the second ranging sensor 42 is installed on the right side of the frame 1. Both are located at the same transverse section at the feed end of the conveyor mechanism 2, with an installation height 20 mm to 50 mm higher than the upper edge of the conveyor belt. The detection optical axes of both the first ranging sensor 41 and the second ranging sensor 42 are perpendicular to the conveying direction 8 of the plate 7 and are respectively positioned towards the two side edges of the plate 7. When the plate 7 passes by, the side edge of the plate 7 enters the laser detection range, and the sensor outputs the distance value from the side edge of the plate 7 to the sensor reference point. If the laser displacement sensor is replaced with a photoelectric through-beam sensor, the sensor and the through-beam receiver are located on opposite sides of the conveyor channel. The plate 7 blocks the light path, generating an on / off signal. The width and position of the plate 7 are calculated by converting the blocking timing and belt speed. This method is less expensive but slightly less accurate, making it suitable for applications where high precision is not required. The controller 6 synchronously samples and filters the two detection values, deducting system errors caused by sensor installation deviations and conveyor belt surface runout during the initialization calibration phase. Based on the above scheme, the dual-sensor arrangement can simultaneously acquire the position information of both edges of the plate 7 on the same cross section. The width and lateral position of the plate 7 can be obtained by cross-calculating two sets of independent readings, resulting in high detection redundancy. Even if the reading of a single sensor is contaminated by paint splashes and drifts, the controller 6 can still identify the anomaly through consistency verification of the readings on both sides, improving the reliability and anti-contamination capability of the detection.

[0051] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any way. Although the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art can make some modifications or alterations to the above-disclosed technical content to create equivalent embodiments without departing from the scope of the present invention. Any simple modifications, equivalent changes and alterations made to the above embodiments based on the technical essence of the present invention without departing from the scope of the present invention shall still fall within the scope of the present invention.

Claims

1. A UV coating equipment, characterized in that, include: Rack (1); The conveying mechanism (2) is mounted on the frame (1) and is used to convey the sheet metal (7). The lamp assembly (3) is located above the conveying mechanism (2) and includes a left short lamp tube (32), a middle lamp tube (31) and a right short lamp tube (33) arranged sequentially along the width of the plate and can be started and stopped independently. The middle lamp tube (31) is longer than the left short lamp tube (32) and the right short lamp tube (33). The left short lamp tube (32) and the right short lamp tube (33) are not on the same axis as the middle lamp tube (31) and are radially offset and axially overlapped. Their illumination direction is oblique to the side of the middle lamp tube (31). The first distance sensor (41) and the second distance sensor (42) are respectively located on both sides of the feed end of the conveying mechanism (2) to detect the width and lateral position of the plate (7); The feeding mechanism (5) includes a left feeding unit (51) and a right feeding unit (52) located on both sides of the feeding end of the conveying mechanism (2). Both the left feeding unit (51) and the right feeding unit (52) include a push cylinder and a push plate. The cylinder body of the push cylinder is fixed to the frame (1), and the push plate is fixed to the end of the piston rod of the push cylinder. The free end of the push plate is provided with an arc-shaped guide. The controller (6) is electrically connected to the lamp group (3), the first distance sensor (41), the second distance sensor (42) and the feeding mechanism (5). It controls the start and stop of each lamp according to the width of the plate (7), and drives the left feeding unit (51) or the right feeding unit (52) according to the lateral position of the plate (7) so that the plate (7) is located in the illumination area of ​​the lit lamp.

2. The UV coating equipment according to claim 1, characterized in that, The lamp assembly (3) also includes a middle lamp cover (311), a left lamp cover (321) and a right lamp cover (331). The middle lamp cover (311) is placed on the outside of the middle lamp tube (31) and the light from the middle lamp tube (31) shines vertically downward. The left lamp cover (321) is placed on the outside of the left short lamp tube (32) and the light from the left short lamp tube (32) shines obliquely towards the middle lamp tube (31). The right lamp cover (331) is placed on the outside of the right short lamp tube (33) and the light from the right short lamp tube (33) shines obliquely towards the middle lamp tube (31). The inner walls of the middle lamp cover (311), the left lamp cover (321) and the right lamp cover (331) are all provided with reflective surfaces.

3. The UV coating equipment according to claim 1, characterized in that, The axial overlap length of the left short tube (32) and the middle tube (31) is equal to the sum of the lengths of the non-light-emitting areas at the ends of the middle tube (31) and the left short tube (32). The axial overlap length of the right short tube (33) and the middle tube (31) is equal to the sum of the lengths of the non-light-emitting areas at the ends of the middle tube (31) and the right short tube (33). The light-emitting area of ​​each short tube extends beyond the splicing seam with the middle tube (31) and fills in the non-light-emitting area at the end of the middle tube (31). The irradiation area of ​​each tube on the surface of the board (7) is connected along the width direction of the board (7).

4. The UV coating equipment according to claim 2, characterized in that, The angle between the light-emitting direction of the left lampshade (321) and the vertical direction is 10 to 30 degrees, and the angle between the light-emitting direction of the right lampshade (331) and the vertical direction is 10 to 30 degrees.

5. The UV coating equipment according to claim 1, characterized in that, The middle section lamp tube (31), the left short lamp tube (32) and the right short lamp tube (33) are all LED ultraviolet lamp strips. The light-emitting length of the middle section lamp tube (31) accounts for 60% of the total light-emitting length of the lamp group (3), and the light-emitting length of the left short lamp tube (32) and the light-emitting length of the right short lamp tube (33) each account for 20% of the total light-emitting length of the lamp group (3).

6. The UV coating equipment according to claim 1, characterized in that, The controller (6) is also configured to: when the width of the plate (7) is less than the illumination width of the middle section lamp tube (31), only the middle section lamp tube (31) is lit; when the width of the plate (7) is greater than the illumination width of the middle section lamp tube (31) and less than the sum of the illumination width of the middle section lamp tube (31) and the illumination width of a short lamp tube, the middle section lamp tube (31) and the left short lamp tube (32) or the right short lamp tube (33) are lit; when the width of the plate (7) is greater than the sum of the illumination width of the middle section lamp tube (31) and the illumination width of a short lamp tube, the middle section lamp tube (31), the left short lamp tube (32) and the right short lamp tube (33) are lit.

7. The UV coating equipment according to claim 1, characterized in that, The left short lamp tube (32), the middle lamp tube (31) and the right short lamp tube (33) are detachably installed on the lamp holder beam (34) through their respective independent lamp holders. The lamp holder beam (34) is mounted on the top of the frame (1) along the width direction of the plate (7). The lamp group (3) also includes an independent power drive circuit that is connected to the three lamp tubes one by one. If any lamp tube is damaged, the lamp tube can be disassembled and replaced separately without disassembling the other lamp tubes and the lamp holder beam (34).

8. A UV coating equipment according to claim 1, characterized in that, The controller (6) is also configured to: calculate the lateral offset of the plate (7) relative to the conveying baseline based on the detection values ​​of the first distance sensor (41) and the second distance sensor (42); when the lateral offset is greater than the preset threshold, drive the feeding unit on the side where the offset direction of the plate (7) is located to move, and push the plate (7) towards the conveying baseline by the push plate until the edge of the plate (7) is aligned with the edge of the illuminated area of ​​the lamp tube.

9. A UV coating equipment according to claim 1, characterized in that, The conveying mechanism (2) is a belt conveying mechanism, including a conveyor belt and a conveying motor. The conveyor belt is wound between the active roller and the driven roller, and the conveying motor drives the active roller to rotate. The extension speed of the piston rod of the push cylinder matches the conveying linear speed of the conveying mechanism (2), so that the plate (7) can be pushed laterally during the conveying process.

10. A UV coating equipment according to claim 1, characterized in that, The first ranging sensor (41) and the second ranging sensor (42) are both laser displacement sensors or photoelectric beam sensors. The detection optical axes of the first ranging sensor (41) and the second ranging sensor (42) are perpendicular to the conveying direction of the plate (7) and are respectively set towards the two sides of the plate (7).

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