Special equipment for overall coating of flat paper, coating method and application

Abstract

The invention discloses special equipment for overall coating of flat paper, a coating method and application, and relates to the technical field of printing. The equipment comprises a base and a workbench, and a paper feeding mechanism and a coating mechanism are arranged on the workbench; the paper feeding mechanism comprises a bottom frame (1), a stand column (2), a bearing plate (3), a paper blocking plate (4), a pneumatic paper supporting plate (5), an upper rotary conveying belt (6), a paper feeding platform (7) and the like. The coating mechanism comprises a coating table, a portal frame (8), a fishbone-shaped support (9), a negative pressure adsorption plate (10), a rotary flexible breathable conveying belt (11), a flexible coating pillow (12) and other components. Flat paper or a trademark is temporarily fixed and conveyed through the negative pressure adsorption mechanism, then the flexible coating pillow (12) and a matched mechanism thereof are used for coating and transferring paint, and when the equipment and the method are used for repairing unconventional trademarks with printing defects, the beneficial effects of being high in efficiency and low in labor intensity are achieved.

Description

Technical Field

[0001] The invention relates to the field of printing technology, and specifically designs special equipment and a coating method for whole-sheet coating of flat paper and applications thereof. Background Art

[0002] Overall coating of flat paper refers to coating the entire surface of flat paper to improve its surface quality and added value. This process can give the paper a smoother surface, better printability, higher opacity, better feel and stronger moisture resistance. Overall coating is mainly divided into two methods: in-machine coating and out-machine coating: In-machine coating refers to setting up a coating unit on the paper machine so that the coating operation and the paper forming process are carried out simultaneously. The advantage of this method is that the coating liquid can be directly applied to the surface of the newly formed paper, and the coating effect is good, which is suitable for high-speed paper machines. However, in-machine coating has high requirements for the coating liquid, which needs to have good rheology and stability to adapt to the high-speed operation and temperature changes of the paper machine; off-machine coating is to apply the coating liquid to the surface of the paper through a coating machine after the paper forming is completed on the paper machine. The advantage of this method is that the surface of the already formed paper can be treated, the coating effect is relatively good, and the requirements for the coating liquid are relatively low.

[0003] Commonly used coating methods include dip coating, roller coating, spray coating, slot coating and extrusion coating, etc. Although these methods can increase the surface strength of paper, reduce dust spots and improve the glossiness of paper, they will also increase the opacity of paper and reduce its stiffness. In addition, the existing coating process will often cause some problems, such as thick head and thin tail, thick edges on both sides, dark spots, rough surface, exposed foil and other defects. Summary of the invention

[0004] One of the purposes of the present invention is to provide a dedicated device for coating a flat sheet of paper as a whole, which can realize rapid full-page coating of the surface of a flat sheet of paper by cooperating with a high-speed transmission mechanism.

[0005] To achieve the above object, the present invention adopts the following technical solution: a dedicated device for overall coating of flat sheets of paper, which is applied to the overall coating operation of flat sheets of paper, comprises a base, a workbench is arranged on the base, the workbench is used to carry a mechanism for conveying paper, and a coating mechanism is installed, and the characteristics are: At the front end position above the workbench, a paper feeding mechanism is arranged, including a base frame 1, columns 2 are arranged on both sides of the base frame 1, an inclined receiving board 3 is arranged in the middle of the base frame 1, a rectangular opening is arranged at the front end of the receiving board 3, and an inclined paper baffle 4 in the box is arranged at the front end of the receiving board 3. The paper baffle 4 is connected and fixed to the column 2 on the side, and a gap is reserved between the bottom of the paper baffle 4 and the receiving board 3; at the front end of the base frame 1, facing the receiving board 3, a height-adjustable inclined pneumatic paper support 5 is arranged to hold the flat paper stack stacked on the receiving board 3 under The upper part of the supporting plate 3 is pushed forward to facilitate the sequential conveying of flat sheets of paper from bottom to top; in addition, rotary conveyor belts are respectively arranged above and below the rectangular opening at the front end of the supporting plate 3, wherein the lower rotary conveyor belt is arranged below the supporting plate 3 and extends backward from the front end to the rear end of the supporting plate 3; and the upper rotary conveyor belt 6 is arranged above the supporting plate 3, and its starting end is aligned with the tail end of the rotary conveyor belt below; a paper feeding platform 7 is arranged between the starting end and the tail end of the upper rotary conveyor belt 6, and an induction counting device is arranged in the paper feeding platform 7.

[0006] Behind the paper feeding mechanism, a coating mechanism is arranged on the workbench, including a coating table and a gantry 8 erected on both sides of the coating table, and a fishbone-shaped bracket 9 is fixed under the crossbeam of the gantry 8 along the direction of the flat paper movement; the coating table includes a negative pressure adsorption plate 10 arranged on the workbench, and a rotary flexible breathable conveyor belt 11 wrapped on the surface of the negative pressure adsorption plate 10, and the front end of the coating table is overlapped with the tail end of the upper rotary conveyor belt 6; in the middle position of the coating table, a long rectangular flexible coating pillow 12 is arranged with a length direction perpendicular to the paper feeding direction, and the flexible coating pillow 12 is connected to the paper feeding direction by a clamping plate 13 is fixed on both sides of the workbench, a plurality of penetration holes are provided on the clamping plate 13, and the two ends are connected to the column 2 by fastening bolts, and the fit between the flexible coating pillow 12 and the coating table can be adjusted; a rigid pressing strip 14 is provided in the middle position of the upper surface of the clamping plate 13 to keep the clamping plate 13 evenly low to apply pressure to the flexible coating pillow 12; at the front end of the fishbone-shaped bracket 9, a coating container 15 is provided, and its lower end is connected to a feeding pipe 16, and the feeding pipe 16 passes through the penetration holes on the clamping strip 14 and the clamping plate 13 and the flexible coating pillow 12, so as to soak the coating on the flexible coating pillow 12; Above the rear half of the coating station, a heating and drying mechanism 17 is fixed to the coating station via a herringbone-shaped bracket 9; Behind the coating station, a paper receiving mechanism is provided, and its structure is consistent with the relevant components in the paper feeding mechanism, including an upper rotary conveyor belt 6, a lower rotary conveyor belt and a paper feeding platform 7, and the paper receiving mechanism is symmetrically arranged with these components; Behind the paper delivery mechanism, an air blowing cooling system is arranged, including a fan 18, a pipeline and an air outlet, wherein the air outlet is perpendicular to the flat sheet of paper that has been coated and dried; The last section is provided with a flat paper collection slot.

[0007] Preferably, the top of the upper rotary conveyor belt 6 is connected to the telescopic rod 6-1, and the upper end of the telescopic rod 6-1 is fixed on a cross bar connected to the two side columns 2. The telescopic rod 6-1 moves to adjust the gap between the upper rotary conveyor belt 6 and the paper feeding platform 7.

[0008] Preferably, the feed pipe 16 is in the form of a main pipe + branch pipes, where one main pipe is connected to a plurality of branch pipes via a distributor; or a structure in which a plurality of branch pipes directly connect the paint container 15 and the flexible coating pillow 12 may be adopted.

[0009] Preferably, the flexible coated pillow 12 adopts a composite structure wrapped with inner and outer layers, wherein the top layer is an elastic material layer 12-1 with a permeable grid, the inner layer is a flexible water-absorbing material layer 12-2, and the bottom layer is a flexible wear-resistant material layer 12-3, wherein the edges of the top layer and the bottom layer are connected to wrap the inner layer as a whole in the middle.

[0010] A second object of the present invention is to provide a method for coating a flat sheet of paper as a whole, characterized in that it comprises the following steps: ① Preparation process for conveying flat sheets of paper to be coated: stack the flat sheets of paper to be coated with the coating side facing upward and feed them into the feed port; ② The flat sheet of paper is moved on the upper surface by the upper conveyor belt at a specific interval frequency, so that it is transported backward in single sheets and transported to the coating station; ③ After the flat sheet of paper is transported to the coating station, it is laid on the flexible breathable conveyor belt 11, and the flat sheet of paper is temporarily fixed on the flexible breathable conveyor belt 11 by the negative pressure adsorption plate 10 fixed below. The flexible breathable conveyor belt 11 circulates and rotates, driving the flat sheet of paper to move backward to the coating station; ④ The coating station uses two gantries 8 to span across the two sides of the coating table perpendicular to the traveling direction. A fully covered flexible coating pillow 12 is set between the two gantries 8. The flat paper is fixed on the flexible breathable conveyor belt 11 by the negative pressure adsorption plate 10 and moves through the flexible coating pillow 12; ⑤ The lower surface of the flexible coated pillow 12 is in close contact with the upper surface of the flat sheet of paper passing thereunder, and the contact order between the flat sheet of paper and the flexible coated pillow 12 is distributed from the paper feed end to the paper discharge end according to the order in which the flat sheet of paper passes through the flexible coated pillow 12; ⑥ The coating flows from the container at the top through the uniform distribution tube and finally infiltrates the flexible coating pillow 12. The upper surface of the flexible coating pillow 12 is subjected to constant pressure by a pressure plate, so that the pressure transmitted to the contact surface between the flat paper and the flexible coating pillow 12 is evenly distributed, and the coating infiltrated on the flexible coating pillow 12 is also evenly distributed; ⑦ The flexible coating pillow 12 coats the coating soaked in the entirety of the flexible coating pillow 12 on the surface of the flat sheet of paper passing through the lower surface thereof, and transports the coated flat sheet of paper backward under the combined action of the negative pressure adsorption plate 10 and the flexible air-permeable conveyor belt 11; ⑧ Drying fan 18 draws in outside air, filters and heats it, and then blows it from the bottom to the coated flat paper, so that the water or solvent in the coating evaporates, allowing the coating and the base paper to be stably and firmly combined together. At the same time, it draws air above the blowing part to collect gas; ⑨ The flat sheets of paper that have been coated and dried are also transported backwards via an overhead conveyor belt for stacking and collection.

[0011] Preferably, the frequency of the shifting and conveying interval of the single flat sheet of paper in step ② is adjusted according to the longitudinal dimension of the flat sheet of paper, and the adjustment range is 0.1-0.5S.

[0012] Preferably, the coating in step ⑥ flows from the container at the top through the uniform distribution pipe and soaks on the flexible coating pillow 12, adopting a "one-to-many" method, that is, the total coating container 15 is connected to a uniform distribution pipe main pipe, and is divided into several branch pipes after passing through the diverter. The branch pipes are connected to the areas equally divided according to the length of the flexible coating pillow 12, and the number of equally divided areas is consistent with the number of branch pipes. This method has a better coating effect when the overall coating thickness is thin and the coating viscosity is small; or a "one-to-one" method is adopted, that is, an independent coating container 15 is connected to a branch pipe, and the branch pipe is directly connected to the areas equally divided according to the length of the flexible coating pillow 12, and the number of equally divided areas is consistent with the number of branch pipes. This method has a better coating effect when the overall coating thickness is thick and the coating viscosity is large.

[0013] In the field of printing, a layer of varnish is usually applied to the outermost layer of a flat sheet of trademark paper for aesthetic purposes after printing. However, during the printing and post-printing stacking process, due to incomplete drying of the varnish on the surface of the printed product, or the use of a relatively soft, high-temperature-intolerant resin as a binder to produce varnish for printing, the heat generated by drying will accumulate inside the paper pile in the printing paper receiving section. Under a certain pressure, the varnish layer on the surface of the printed product will stick to the back and become blurred. During the post-printing stacking process, the printed products will stick to each other, causing uneven defects on the surface of the printed product. Therefore, the third purpose of the present invention is to provide a specific application of the above-mentioned flat sheet coating device and method, using the above-mentioned coating device and coating method to eliminate surface defects of flat sheet trademarks, that is, a method for eliminating surface defects of trademarks using a flat sheet coating device, characterized in that it includes the following steps: Step 1: stack the defective trademarks and place them on the supporting board 3, with the front side against the paper stopper 4, open the inclined pneumatic paper support 5, and push the lower part of the defective trademarks stacked on the supporting board 3 forward, so that the lower end faces forward and the upper end faces backward; Step 2: The defective trademark is driven and clamped by the lower rotary conveyor belt and the upper rotary conveyor belt 6 and transported to the coating station in a single sheet; Step 3: The defective trademark is located above the flexible air-permeable conveyor belt 11 of the coating station, and the negative pressure adsorption plate 10 below adsorbs and fixes the defective trademark on the flexible air-permeable conveyor belt 11 through the flexible air-permeable conveyor belt 11, and the flexible air-permeable conveyor belt 11 drives the flat paper to move backward; Step 4: The defective trademark passes under the flexible coated pillow 12, and the flexible wear-resistant material layer 12-3 at the bottom of the flexible coated pillow 12 is in close contact with the upper surface of the defective trademark passing under it; Step 5: The solvent is distributed on the flexible coating pillow 12 through the pipeline from the top container, and at the same time, the upper surface of the flexible coating pillow 12 is constantly pressurized by the pressure plate, so that the solvent is evenly infiltrated on the lower surface of the flexible coating pillow 12; Step 6: After the defective trademark passes through the flexible coating pillow 12, the solvent is evenly coated on its surface, and the coated defective trademark is transported backward under the joint action of the negative pressure adsorption plate 10 and the flexible breathable conveyor belt 11; after the solvent is coated on the surface of the defective trademark, the resin in the varnish layer of the defective part will be re-dissolved in the solvent, and re-leveled under the action of surface tension to eliminate the uneven defects; Step 7: Dry and cool the coated trademark to evaporate the excess solvent, and keep the original printing layer on the trademark flat again. The trademark is transported backwards via a conveyor belt and stacked for collection.

[0014] Preferably, the solvent is an industrial cleaning solvent, including white spirit or anhydrous alcohol.

[0015] Beneficial effects: The key technical point of the overall coating equipment, method and specific application of flat paper described in the present application is to temporarily fix and convey the flat paper or trademark through a negative pressure adsorption mechanism, and then use the flexible coating pillow 12 with a multi-layer composite structure and its supporting feeding and fixing mechanism to convey, adsorb and coat the coating or solvent. Compared with the dip coating, roller coating or spray coating methods used in the prior art, the paper conveying mechanism is simpler, the conveying process is more stable, and the coating amount of the coating or solvent is more accurately controlled, with less consumption.

[0016] In addition, when using the above-mentioned equipment and method to perform unconventional repair operations on trademarks with printing defects, it solves the problem that after the trademark is printed once, the paper thickness, ductility and friction coefficient change and cannot be directly processed using traditional printing or coating equipment. It can flexibly repair defective trademarks in large and small batches, improve efficiency, and reduce the labor intensity of operators. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1It is a schematic diagram of the structure of the dedicated equipment for overall coating of flat sheets of paper described in Example 1.

[0018] Figure 2 The upper rotary conveyor belt is a schematic structural diagram.

[0019] Figure 3 It is a schematic diagram of the installation structure of the flexible coated pillow.

[0020] Figure 4 It is a schematic diagram of the internal structure of the flexible coated pillow.

[0021] Figure 5 It is a schematic diagram of the structure of the dedicated equipment for overall coating of flat sheets of paper described in Example 2.

[0022] In the figure: base frame 1, column 2, supporting plate 3, paper baffle 4, pneumatic paper support 5, upper rotary conveyor belt 6, telescopic rod 6-1, paper feeding platform 7, gantry 8, herringbone bracket 9, negative pressure adsorption plate 10, flexible breathable conveyor belt 11, flexible coating pillow 12, elastic material layer 12-1, flexible water-absorbing material layer 12-2, flexible wear-resistant material layer 12-3, splint 13, compression strip 14, paint container 15, feeding pipe 16, heating and drying mechanism 17, fan 18. DETAILED DESCRIPTION

[0023] The present invention is further described below in conjunction with the accompanying drawings and embodiments. Example 1

[0024] like Figure 1-4As shown, the present embodiment of the invention is a special equipment for coating flat sheets of paper as a whole, comprising a base, a workbench is arranged on the base, the workbench is used for carrying a mechanism for conveying paper, and installing a coating mechanism, and a paper feeding mechanism is arranged at the front end position above the workbench, comprising a base frame 1, columns 2 are arranged on both sides of the base frame 1, an inclined receiving plate 3 is arranged in the middle of the base frame 1, a rectangular opening is arranged at the front end of the receiving plate 3, an inclined paper baffle 4 in the box is arranged at the front end of the receiving plate 3, the paper baffle 4 is connected and fixed to the side columns 2, and a gap is reserved between the bottom of the paper baffle 4 and the receiving plate 3; at the front end of the base frame 1, at a position directly opposite to the receiving plate 3, a height-adjustable inclined pneumatic paper support 5 is arranged, which pushes the lower part of the flat paper stack stacked on the receiving plate 3 forward for convenience in flattening Sheets of paper are conveyed sequentially from bottom to top; in addition, rotary conveyor belts are respectively arranged above and below the rectangular opening at the front end of the supporting plate 3, wherein the lower rotary conveyor belt is arranged below the supporting plate 3 and extends backward from the front end to the rear end of the supporting plate 3; and the upper rotary conveyor belt 6 is arranged above the supporting plate 3, and its starting end is aligned with the tail end of the rotary conveyor belt below; a paper feeding platform 7 is arranged between the starting end and the end end of the upper rotary conveyor belt 6, and an induction counting device is arranged in the paper feeding platform 7; the top of the upper rotary conveyor belt 6 is connected to the telescopic rod 6-1, and the upper end of the telescopic rod 6-1 is fixed on the cross bar connected to the two side columns 2, and the telescopic rod 6-1 is moved to adjust the gap between the upper rotary conveyor belt 6 and the paper feeding platform 7.

[0025] Behind the paper feeding mechanism, a coating mechanism is arranged on the workbench, including a coating table and a gantry 8 erected on both sides of the coating table, and a fishbone-shaped bracket 9 is fixed under the crossbeam of the gantry 8 along the direction of the flat paper movement; the coating table includes a negative pressure adsorption plate 10 arranged on the workbench, and a rotary flexible breathable conveyor belt 11 wrapped on the surface of the negative pressure adsorption plate 10, and the front end of the coating table is overlapped with the rear end of the upper rotary conveyor belt 6; in the middle position of the coating table, a long rectangular flexible conveyor belt 11 is arranged with a length direction perpendicular to the paper feeding direction. The flexible coating pillow 12 is fixed on both sides of the workbench by a clamping plate 13, a plurality of penetration holes are provided on the clamping plate 13, and both ends are connected to the column 2 by fastening bolts, and the fit between the flexible coating pillow 12 and the coating table can be adjusted; the flexible coating pillow 12 adopts a composite structure wrapped with inner and outer layers, wherein the uppermost layer is an elastic material layer 12-1 with a penetration grid, the inner layer is a flexible water-absorbing material layer 12-2, and the bottom layer is a flexible wear-resistant material layer 12-3, wherein the edges of the uppermost layer and the bottom layer are connected, and the inner layer is integrally wrapped. The body is wrapped in the middle; a rigid compression strip 14 is arranged in the middle position of the upper surface of the splint 13 to keep the splint 13 evenly low and apply pressure to the flexible coating pillow 12; a coating container 15 is arranged at the front end of the herringbone-shaped bracket 9, and its lower end is connected to a feeding pipe 16. The feeding pipe 16 adopts the form of a main pipe + branch pipe. A main pipe is connected to a plurality of branch pipes through a distributor. The feeding pipe 16 passes through the penetration holes on the compression strip 14 and the splint 13 and the flexible coating pillow 12 to soak the coating on the flexible coating pillow 12; Above the rear half of the coating station, a heating and drying mechanism 17 is fixed to the coating station through a herringbone bracket 9; behind the coating station, a paper collection mechanism is arranged, and its structure is consistent with the relevant components in the paper feeding mechanism, including an upper rotary conveyor belt 6, a lower rotary conveyor belt and a paper feeding platform 7, and the paper collection mechanism is symmetrically arranged with these components; behind the paper collection mechanism, an air blowing cooling system is arranged, including a fan 18, a pipe and an air outlet, wherein the air outlet is perpendicular to the flat sheet of paper that has been coated and dried; and a flat sheet of paper collecting trough is arranged in the last section.

[0026] In the overall coating method of flat paper, follow the steps below: ① Preparation process for conveying flat sheets of paper to be coated: stack the flat sheets of paper to be coated with the coating side facing upward and feed them into the feed port; ② The flat paper is conveyed backwards in single sheets to the coating station by moving its upper surface at an interval frequency of 0.1-0.5S via the upper conveyor belt; ③ After the flat sheet of paper is transported to the coating station, it is laid on the flexible breathable conveyor belt 11, and the flat sheet of paper is temporarily fixed on the flexible breathable conveyor belt 11 by the negative pressure adsorption plate 10 fixed below. The flexible breathable conveyor belt 11 circulates and rotates, driving the flat sheet of paper to move backward to the coating station; ④ The coating station uses two gantries 8 to span across the two sides of the coating table perpendicular to the traveling direction. A fully covered flexible coating pillow 12 is set between the two gantries 8. The flat paper is fixed on the flexible breathable conveyor belt 11 by the negative pressure adsorption plate 10 and moves through the flexible coating pillow 12; ⑤ The lower surface of the flexible coated pillow 12 is in close contact with the upper surface of the flat sheet of paper passing thereunder, and the contact order between the flat sheet of paper and the flexible coated pillow 12 is distributed from the paper feed end to the paper discharge end according to the order in which the flat sheet of paper passes through the flexible coated pillow 12; ⑥ The coating flows from the container at the top through the uniform distribution tube and finally infiltrates the flexible coating pillow 12. The upper surface of the flexible coating pillow 12 is subjected to constant pressure by a pressure plate, so that the pressure transmitted to the contact surface between the flat paper and the flexible coating pillow 12 is evenly distributed, and the coating infiltrated on the flexible coating pillow 12 is also evenly distributed; ⑦ The flexible coating pillow 12 coats the coating soaked in the entirety of the flexible coating pillow 12 on the surface of the flat sheet of paper passing through the lower surface thereof, and transports the coated flat sheet of paper backward under the combined action of the negative pressure adsorption plate 10 and the flexible air-permeable conveyor belt 11; ⑧ Drying fan 18 draws in outside air, filters and heats it, and blows it from below to the coated flat paper, so that the water or solvent in the coating evaporates, allowing the coating and the base paper to be stably and firmly combined together. At the same time, it draws air above the blowing part to collect gas; ⑨ The flat sheets of paper that have been coated and dried are also transported backwards via an overhead conveyor belt for stacking and collection. Example 2

[0027] like Figure 2-5 As shown, this embodiment provides a method for eliminating trademark surface defects using a flat paper coating device, comprising the following steps: Step 1: stack the defective trademarks and place them on the supporting board 3, with the front side against the paper stopper 4, open the inclined pneumatic paper support 5, and push the lower part of the defective trademarks stacked on the supporting board 3 forward, so that the lower end faces forward and the upper end faces backward; Step 2: The defective trademark is driven and clamped by the lower rotary conveyor belt and the upper rotary conveyor belt 6 and transported to the coating station in a single sheet; Step 3: The defective trademark is located above the flexible air-permeable conveyor belt 11 of the coating station, and the negative pressure adsorption plate 10 below adsorbs and fixes the defective trademark on the flexible air-permeable conveyor belt 11 through the flexible air-permeable conveyor belt 11, and the flexible air-permeable conveyor belt 11 drives the flat paper to move backward; Step 4: The defective trademark passes under the flexible coated pillow 12, and the flexible wear-resistant material layer 12-3 at the bottom of the flexible coated pillow 12 is in close contact with the upper surface of the defective trademark passing under it; Step 5: white spirit is distributed on the flexible coating pillow 12 from the container at the top through a pipe, and the pipe adopts a "one-to-one" method, that is, an independent coating container 15 is connected to a branch pipe, and the branch pipe is directly connected to the area divided equally according to the length of the flexible coating pillow 12, and the number of equally divided areas is consistent with the number of branch pipes. This method has a better coating effect when the overall coating thickness is thick and the coating viscosity is high; at the same time, the upper surface of the flexible coating pillow 12 is constantly pressurized by a pressure plate, so that the solvent is evenly infiltrated on the lower surface of the flexible coating pillow 12; Step 6: After the defective trademark passes through the flexible coating pillow 12, the solvent is evenly coated on its surface, and the coated defective trademark is transported backward under the joint action of the negative pressure adsorption plate 10 and the flexible breathable conveyor belt 11; after the solvent is coated on the surface of the defective trademark, the resin in the varnish layer of the defective part will be re-dissolved in the solvent, and re-leveled under the action of surface tension to eliminate the uneven defects; Step 7: Dry and cool the coated trademark to evaporate the excess solvent, and keep the original printing layer on the trademark flat again. The trademark is transported backwards via a conveyor belt and stacked for collection.

[0028] The above embodiments are merely illustrative of the principles and effects of the present invention, and are not intended to limit the present invention. Anyone familiar with the art may modify or alter the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or alterations made by a person of ordinary skill in the art without departing from the spirit and technical concept disclosed by the present invention shall still be covered by the claims of the present invention.

Claims

1. A dedicated device for coating a flat sheet of paper as a whole, which is used for coating a flat sheet of paper as a whole, comprises a base, a workbench is arranged on the base, the workbench is used to carry a mechanism for conveying paper, and a coating mechanism is installed, and is characterized in that: A paper feeding mechanism is arranged at the front end position above the workbench, comprising a base frame (1), columns (2) are arranged on both sides of the base frame (1), an inclined support plate (3) is arranged in the middle of the base frame (1), a rectangular opening is arranged at the front end of the support plate (3), an inclined paper baffle (4) in the box is arranged at the front end of the support plate (3), the paper baffle (4) is connected and fixed to the columns (2) on the side, and a gap is reserved between the bottom of the paper baffle (4) and the support plate (3); at the front end of the base frame (1), directly facing the support plate (3), a height-adjustable inclined pneumatic paper support (5) is arranged to hold the paper stacked on the support plate (3) ) is pushed forward at the bottom of the flat paper stack on the support plate (3), so as to facilitate the sequential transportation of the flat paper sheets from bottom to top; in addition, rotary conveyor belts are respectively arranged above and below the rectangular opening at the front end of the support plate (3), wherein the lower rotary conveyor belt is arranged below the support plate (3) and extends backward from the front end to the rear end of the support plate (3); and the upper rotary conveyor belt (6) is arranged above the support plate (3), and its starting end is aligned with the rear end of the rotary conveyor belt below; a paper feeding platform (7) is arranged between the starting end and the rear end of the upper rotary conveyor belt (6), and an induction counting device is arranged in the paper feeding platform (7); Behind the paper feeding mechanism, a coating mechanism is arranged on the workbench, including a coating platform and a gantry (8) erected on both sides of the coating platform, and a fishbone-shaped bracket (9) is fixed under the crossbeam of the gantry (8) along the direction of the flat paper sheet traveling; the coating platform includes a negative pressure adsorption plate (10) arranged on the workbench, and a rotary flexible breathable conveyor belt (11) wrapped on the surface of the negative pressure adsorption plate (10), and the front end of the coating platform is overlapped with the rear end of the upper rotary conveyor belt (6); at the middle position of the coating platform, a long rectangular flexible coating pillow (12) whose length direction is perpendicular to the paper feeding direction is arranged, and the flexible coating pillow (12) is fixed to the coating platform by a clamping plate (13). A plurality of penetration holes are provided on the clamping plate (13) on both sides of the workbench, and the two ends are connected to the column (2) by fastening bolts, and the fit between the flexible coating pillow (12) and the coating table can be adjusted; a rigid pressing strip (14) is provided at the middle position of the upper surface of the clamping plate (13) to keep the clamping plate (13) evenly low to apply pressure to the flexible coating pillow (12); a coating container (15) is provided at the front end of the herringbone-shaped bracket (9), and the lower end of the coating container is connected to the feeding pipe (16), and the feeding pipe (16) passes through the penetration holes on the clamping strip (14) and the clamping plate (13) and the flexible coating pillow (12), so as to soak the coating on the flexible coating pillow (12); Above the rear half of the coating table, a heating and drying mechanism (17) is fixed via a herringbone-shaped bracket (9) facing the coating table; A paper receiving mechanism is arranged behind the coating station, and its structure is consistent with the relevant components in the paper feeding mechanism, including an upper rotary conveyor belt (6), a lower rotary conveyor belt and a paper feeding platform (7), and the paper receiving mechanism is arranged symmetrically with these components; An air blowing cooling system is arranged behind the paper delivery mechanism, comprising a fan (18), a pipeline and an air outlet, wherein the air outlet is perpendicular to the flat sheet of paper that has been coated and dried; The last section is provided with a flat paper collection slot.

2. The dedicated equipment for overall coating of flat paper according to claim 1, characterized in that: The top of the upper rotary conveyor belt (6) is connected to a telescopic rod (6-1), and the upper end of the telescopic rod (6-1) is fixed to a crossbar connected to the two side columns (2). The telescopic rod (6-1) moves to adjust the gap between the upper rotary conveyor belt (6) and the paper feeding platform (7).

3. The dedicated equipment for overall coating of flat paper according to claim 1, characterized in that: The feeding pipe (16) is in the form of a main pipe + branch pipes, wherein one main pipe is connected to a plurality of branch pipes via a distributor.

4. The dedicated equipment for overall coating of flat paper according to claim 1, characterized in that: The feeding pipe (16) adopts a structure in which a plurality of branch pipes are directly connected to the coating container (15) and the flexible coating pillow (12).

5. The dedicated equipment for overall coating of flat paper according to claim 1, characterized in that: The flexible coated pillow (12) adopts a composite structure with inner and outer layers wrapped, wherein the top layer is an elastic material layer (12-1) having a permeable grid, the inner layer is a flexible water-absorbing material layer (12-2), and the bottom layer is a flexible wear-resistant material layer (12-3), wherein the edges of the top layer and the bottom layer are connected to wrap the inner layer as a whole in the middle.

6. A method for coating a flat sheet of paper as a whole, characterized in that: The following steps are involved: ① Preparation process for conveying flat sheets of paper to be coated: stack the flat sheets of paper to be coated in a standard manner with the coated surface facing upward and feed them into the feed port; ② The flat sheet of paper is moved on the upper surface by the upper conveyor belt at a specific interval frequency, so that it is transported backward in single sheets and transported to the coating station; ③ After the flat sheet of paper is transported to the coating station, it is laid on top of the flexible breathable conveyor belt (11), and the flat sheet of paper is temporarily fixed on the flexible breathable conveyor belt (11) by a negative pressure adsorption plate (10) fixed below. The flexible breathable conveyor belt (11) circulates and rotates, driving the flat sheet of paper to move backward to the coating station; ④ The coating station uses two gantries (8) spanning across the two sides of the coating table perpendicular to the traveling direction, and a fully covered flexible coating pillow (12) is arranged between the two gantries (8). The flat paper is fixed on the flexible breathable conveyor belt (11) by the negative pressure adsorption plate (10) and moves through the flexible coating pillow (12); ⑤ The lower surface of the flexible coating pillow (12) is in close contact with the upper surface of the flat sheet of paper passing thereunder, and the order in which the flat sheet of paper contacts the flexible coating pillow (12) is distributed from the paper feed end to the paper discharge end according to the order in which the flat sheet of paper passes through the flexible coating pillow (12); ⑥ The coating flows from the container at the top through the uniform distribution tube and finally soaks on the flexible coating pillow (12), and a pressure plate is used to apply constant pressure to the entire upper surface of the flexible coating pillow (12), so that the pressure transmitted to the contact surface between the flat paper and the flexible coating pillow (12) is evenly distributed, and at the same time, the coating soaked on the flexible coating pillow (12) is kept evenly distributed; ⑦ The flexible coating pillow (12) coats the coating impregnated in the entirety of the pillow onto the surface of the flat sheet of paper passing under the pillow, and transports the coated flat sheet of paper backward under the combined action of the negative pressure adsorption plate (10) and the flexible air-permeable conveyor belt (11); ⑧ The drying fan (18) draws in outside air, filters and heats it, and then blows it from the bottom to the coated flat paper, so that the water or solvent in the coating evaporates, allowing the coating and the base paper to be stably and firmly bonded together. At the same time, the air is drawn above the blowing area to collect the gas; ⑨ The flat sheets of paper that have been coated and dried are also transported backwards via an overhead conveyor belt for stacking and collection.

7. A method for coating a flat sheet of paper as claimed in claim 6, characterized in that: The frequency of the shifting and conveying interval of the single flat sheet of paper in step ② is adjusted according to the longitudinal dimension of the flat sheet of paper, and the adjustment range is 0.1-0.5S.

8. A method for coating a flat sheet of paper as claimed in claim 6, characterized in that: In step ⑥, the coating material flows from the top container through the uniform distribution pipe and soaks on the flexible coating pillow (12), using a "one-to-many" method, that is, the total coating container (15) is connected to a uniform distribution pipe main pipe, and after passing through the splitter, it is divided into a plurality of branch pipes, and the branch pipes are connected to the areas that are equally divided according to the length of the flexible coating pillow (12), and the number of equally divided areas is consistent with the number of branch pipes. This method has a better coating effect when the overall coating thickness is thin and the coating viscosity is low; or a "one-to-one" method is used, that is, an independent coating container (15) is connected to a branch pipe, and the branch pipe is directly connected to the areas that are equally divided according to the length of the flexible coating pillow (12), and the number of equally divided areas is consistent with the number of branch pipes.

9. A method for eliminating trademark surface defects using the dedicated equipment for overall coating of flat paper as claimed in claim 1, characterized in that: The following steps are involved: Step 1: stack the defective trademarks and place them on the supporting plate (3), with the front side against the paper stopper (4), open the inclined pneumatic paper support (5), and push the lower part of the defective trademarks stacked on the supporting plate (3) forward, so that the lower end faces forward and the upper end faces backward; Step 2: The defective trademark is driven and clamped by the lower rotary conveyor belt and the upper rotary conveyor belt (6) and transported to the coating station in a single sheet; Step 3: The defective trademark is located above the flexible air-permeable conveyor belt (11) of the coating station, and the negative pressure adsorption plate (10) below adsorbs and fixes the defective trademark on the flexible air-permeable conveyor belt (11) through the flexible air-permeable conveyor belt (11), and the flexible air-permeable conveyor belt (11) drives the flat sheet of paper to move backward; Step 4: the defective trademark passes under the flexible coated pillow (12), and the flexible wear-resistant material layer (12-3) at the bottom of the flexible coated pillow (12) is in close contact with the upper surface of the defective trademark passing under it; Step 5: The solvent is distributed from the container at the top onto the flexible coating pillow (12) through a pipe, and at the same time, a pressure plate is used to apply constant pressure to the entire upper surface of the flexible coating pillow (12), so that the solvent is evenly infiltrated onto the lower surface of the flexible coating pillow (12); Step 6: After the defective trademark passes through the flexible coating pillow (12), the solvent is evenly coated on its surface, and the coated defective trademark is transported backward under the joint action of the negative pressure adsorption plate (10) and the flexible breathable conveyor belt (11); after the solvent is coated on the surface of the defective trademark, the resin in the varnish layer of the defective part will be re-dissolved in the solvent, and re-leveled under the action of surface tension, thereby eliminating the uneven defects; Step 7: Dry and cool the coated trademark to evaporate the excess solvent, and keep the original printing layer on the trademark flat again. The trademark is transported backwards via a conveyor belt and stacked for collection.

10. The method for eliminating trademark surface defects according to claim 9, characterized in that: The solvent is an industrial cleaning solvent, including white spirit or anhydrous alcohol.

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