CN214975269U

CN214975269U - Coating roller white-remaining type transfer coating equipment

Info

Publication number: CN214975269U
Application number: CN202121047943.1U
Authority: CN
Inventors: 刘艳侠; 张治博; 马安博; 赵冲冲; 于天恒
Original assignee: Zhengzhou Institute of Emerging Industrial Technology
Current assignee: Zhengzhou Institute of Emerging Industrial Technology
Priority date: 2021-05-17
Filing date: 2021-05-17
Publication date: 2021-12-03
Anticipated expiration: 2031-05-17

Abstract

The utility model discloses a scribble roller and stay white formula transfer coating equipment, including unwinding device, drying cabinet and the coiling mechanism that rectifies, coating unit is equipped with the comma roller directly over the roller including scribbling roller and back of the body roller, scribbles the roller upper left side and is equipped with fixed hopper, scribbles the upper right side of roller and is equipped with and stays white the scraper, stays white to be equipped with on the scraper and accomodates the cavity, accomodates cavity and thick liquids recovery tube intercommunication, is equipped with the delivery pump on the thick liquids recovery tube, and the discharge end of thick liquids recovery tube communicates with the feed inlet of fixed hopper. When the coating area starts, no action that the back roll is close to the coating roll exists, no obvious bulge exists in the abnormal area of the coating head, and no special control is needed; the coating area does not have the action that the backing roll kept away from the coating roller when finishing, and the thick liquids that have coated to the coating substrate can not be dragged by the thick liquids on the coating roller, and coating tail abnormal region can not have obvious tailing and thickness anomaly, leaves in the white scraper directly scrapes the thick liquids in the coating area and pumps back to fixed hopper, saves thick liquids and alleviates operating personnel work burden.

Description

Coating roller white-remaining type transfer coating equipment

Technical Field

The utility model belongs to the technical field of lithium cell production facility, in particular to scribble roller and leave white formula transfer coating equipment.

Background

The production and the manufacture of the lithium battery need to be completed by a series of working procedures, the final performance quality of the lithium battery is not closely classified with the preparation process of the working procedures, and the method can be roughly divided into the main steps of slurry preparation, coating and sheet preparation, battery core assembly, liquid injection and aging, formation and secondary sealing and the like. The coating process of the battery pole piece in the initial stage is finished, the quality of the coating quality directly determines the quality of the battery pole piece, and the battery pole piece determines most performances of the battery, so that the coating process is very important in the whole battery manufacturing process.

Coating is a second procedure in the whole battery preparation process, and is used for uniformly and reliably coating the prepared liquid slurry on positive and negative base materials, removing the liquid flux in the positive and negative base materials through baking, and leaving a solid active material, wherein the thickness and the quality of the coated pole piece are required to be uniform and stable, so that the surface density of each pole piece is ensured to be within a controllable range; because the edge is easy to be pressed and dead when rolling, and the activity of the material can not be exerted in the chemical reaction, the edge thickness needs to be properly reduced when coating, the edge of the pole piece needs to be thinned, and the edge pressing and the material falling in the subsequent process are avoided; after drying, the materials and the base material are required to be firmly bonded, the humidity of the pole piece is moderate, the pole piece and the slurry should be kept clean in the coating process, the pole piece is ensured not to be polluted by dust, stains and other foreign matters, and the battery is ensured to have good consistency and safety. The current common coating technology generally has a better control means for the coating surface density and the drying effect, but has certain difficulty for controlling edge thinning.

The existing coating machine generally uses a three-roller transfer type structure. Wherein the three-roller transfer structure is shown in figure 1, the central core position of the coating structure is a rotatable coating roller 1, one side of the coating roller 1 is provided with a fixed hopper 4 for containing fluid slurry, the other side is provided with a back roller 3, the back roller is provided with a base material for attaching the fluid slurry, the back roller 3 and the coating roller 1 rotate clockwise during coating, the back roller 3 reciprocates in the horizontal direction simultaneously, is continuously attached to and away from the coating roller 1 and is coated during attachment, the slurry on the surface of the coating roller 1 is transferred onto the base material through friction to form a section of coating area, the coating is not carried out when the coating roller 1 is away from the coating roller 1, a section of white area is left on the base material, a comma roller 2 capable of moving up and down is arranged above the coating roller 1, the comma roller is provided with a linear knife edge 2-1 and a standby linear knife edge 2-2 processed according to certain requirements, the comma roller 2 controls the size of a slit between the linear knife edge and the coating roller 1 through the up and down movement, thereby controlling the amount of the slurry passing through the slit and finally achieving the purpose of controlling the density of the coated surface. During coating, the unreeling device 13 unreels the substrate at a constant speed to pass through the coating device, and after coating slurry, the substrate is sent into a drying oven to be dried and coiled into a polar coil by a coiling structure.

When coating, the prepared fluid slurry is added into a fixed hopper, a comma roller 2 is arranged to run downwards, a uniform slit is formed between the back roll and the coating roll 1, the back roll 3 is tightly attached to the coating roll 1 and simultaneously starts to rotate clockwise, the coating roll 1 drives the slurry in the fixed hopper 4 to be attached to the surface of the coating roll when rotating, the slurry is strickled by the linear knife edge 2-1 to form uniform thickness when passing through the slit, and is extruded when reaching the position where the back roll is contacted with the coating roll through the slit, under the action of the relative motion of the coating roller and the back roller, all the materials are uniformly transferred to the base material on the surface of the back roller 3, when the coating is applied to the white space area, the back roller is driven by the servo motor and the ball screw to be away from the coating roller rapidly, the slurry can not be taken away, a section of white space is generated on the base material, and the base material is sent into a drying box to be dried along with the rotation of the backing roll 3. The section of residual slurry 1-6 left on the coating roller in the white leaving area cannot be coated on a base material, the residual slurry is transferred to a residual material scraper 1-5 along with the rotation of the coating roller, the residual material scraper is uniformly attached to the coating roller, the residual slurry is scraped by the scraper and drips into a recovered material receiving disc 1-7 for collection, and the collected residual slurry is intensively discarded or reprocessed for utilization.

The prior art scheme changes the coating thickness by two measures: 1. the size of a slit between the coating roller and the comma roller is changed to directly adjust the thickness of the sizing agent on the coating roller; 2. the relative speed between the coating roller and the backing roller is adjusted so as to adjust the speed of transferring the slurry to the base material, thereby achieving the purpose of changing the coating thickness. When coating begins, the process that the backing roll is laminated to the coating roll needs to have a faster push speed, simultaneously in order that thick liquids can shift totally, need use great strength to make the backing roll compress tightly the coating roll, the backing roll can produce the striking to the coating roll this moment, and produce slight deformation, thick liquids that adhere to on the surface of coating roll receive the backing roll oppression can bulge in contact point both sides, thickness is thicker than other regions, and this thickness can be changed along with the change of thick liquids composition, attribute and coating control parameter, the variation is uncontrollable.

If the coating parameters are not adjusted, the thickness of the coating head is slightly thicker than that of a normal coating area, parameters such as a coating speed ratio, a pushing stroke, a kneading speed and the like need to be debugged, and the speed ratio of the coating roller and the back roller is adjusted to generate a large coating error due to the fact that the back roller and the coating roller are kneaded to cause the head to be thicker, so that the thickness of the coating head is difficult to control; at the end of the coating area and at the beginning of the gap area, the backing roll needs to be far away from the surface of the coating roll, the slurry coated on the surface of the base material and the slurry remained on the coating roll can be separated along with the coating roll, because the slurry belongs to non-Newtonian fluid and has certain viscosity, pits and needle-shaped tailing can be generated at the tail part of the coating area due to surface tension and viscosity during separation, the relative speed of the coating roll and the backing roll and the parameters such as the bouncing speed and the pushing stroke of the backing roll need to be adjusted in order to eliminate the pits and the tailing as far as possible, and therefore, the thickness of the tail part of the coating area is difficult to accurately control. Thus causing the head and tail regions to be susceptible to thickness anomalies. The thickness abnormality leads to the promotion of process loss on the one hand, has wasted manpower and materials, still leads to the unstability of surface density and thickness simultaneously, brings adverse effect for battery safety.

The thicknesses of the head part and the tail part of the coating area are too thin and too thick, so that the process parameters are required to be adjusted for finding the optimal control point for many times in the production process, time and labor are wasted, the thicknesses of the abnormal areas 1-12 of the coating head and the abnormal areas 1-11 of the coating tail are very difficult to control, the production efficiency is influenced while materials are wasted, the performance of a battery pole piece is adversely affected due to the abnormal thicknesses of the coating head and the coating tail, and lithium precipitation or abnormal battery thickness can be generated.

In order to ensure the stability of the density of a coating surface, the coating roller, the back roller and the comma roller need to have high precision in the working process, the coating roller is required to rotate around a shaft center, the roller surface does not jump, the comma roller is fixed, and a straight line knife edge between the coating roller and the comma roller is consistent in left and right and has constant size. However, the back roll continuously impacts the coating roll in the kneading and popping processes, and the coating roll generates slight vibration, so that the stability of the slurry passing through a straight edge is adversely affected, the coating consistency is reduced, and hidden troubles are brought to the reliability and safety of the battery.

SUMMERY OF THE UTILITY MODEL

To conventional three-roller transfer formula coating machine head and the tail skive when the coating and be difficult to control and the undulant problem of density production, the utility model discloses a scribble the roller and leave white formula and shift coating equipment, use when the coating and leave white scraper and directly scrape the regional thick liquids of leaving white on scribbling the roller to in the thick liquids recovery tube conveying returns fixed hopper, the back of the body roller directly pastes tight coating roller under servo motor and ball screw's drive when beginning the coating, the coating in-process need not to promote repeatedly and bounce off, avoided the striking repeatedly of back of the body roller to scribbling the roller, eliminated the vibrations that the striking arouses. Meanwhile, the slurry in the white area on the coating roller is scraped, so that the white area does not need to be flicked, the accumulation of the slurry on the surface of the coating roller when the traditional three-roller transfer coating is kneaded on a back roller and the adhesion and dragging between the slurries when the slurry is flicked are avoided, the slurry can be uniformly coated on a base material, and the thickness of the head and the tail of the coating area is easily controlled. The coating roller white-remaining type transfer coating equipment can effectively improve the stability of coating thickness, improve the quality of pole pieces, greatly reduce the times of parameter debugging during coating, improve the working efficiency, directly pump slurry in a white-remaining area in a pipeline and send the slurry back to a fixed hopper, avoid contact and settlement with air to the maximum extent and reduce the waste of materials.

The technical scheme of the utility model is realized like this: the utility model provides a scribble roller and stay white formula and shift coating equipment, includes unwinding device, drying cabinet and coiling mechanism, the coating device of rectifying, coating device is equipped with the comma roller including scribbling roller and back of the body roller directly over scribbling the roller, scribbles the roller upper left side and is equipped with fixed hopper, the upper right side of scribbling the roller is equipped with and stays white the scraper, stays to be equipped with on the white scraper and accomodates the cavity, accomodates cavity and thick liquids recovery tube intercommunication, is equipped with the delivery pump on the thick liquids recovery tube, and the discharge end of thick liquids recovery tube communicates with the feed inlet of fixed hopper.

As an improvement of the invention, the back roller is arranged at the lower right part of the coating roller, in particular to the contact position of the back roller and the coating roller is in the area below the opposite side of the coating roller and the fixed hopper.

As an improvement of the invention, a white scraper and a slurry recovery pipe which can scrape the slurry on the coating roller and can pump the slurry back into the fixed hopper are additionally arranged. Because the thick liquids in the margin region are returned to the fixed hopper by the margin scraper and the pump of thick liquids recovery tube, consequently do not have remaining thick liquids on the back roll back-coating roller, consequently need not to use clout scraper and reclaimed materials flange, avoided scraper to change and thick liquids extravagant.

Further, the blank scraper is connected with a driving device, the driving device comprises a servo motor and a ball screw, the knife edge of the blank scraper can be tightly attached to the coating roller under the action of the driving device, the slurry on the surface of the coating roller is scraped and collected in the accommodating cavity and is pumped back to the fixed hopper through the slurry recovery pipe, and a section of blank area is formed on the surface of the coating roller. The blade of the scraper contacted with the coating roller is made of a smooth sheet-shaped flexible scraper, the scraper can be tightly attached to the surface of the coating roller to scrape slurry without applying a large acting force on the coating roller, and the smooth flexible scraper cannot damage the surface of the coating roller.

Further, the coating roller, the comma roller and the back roller are respectively connected with a driving device, and the coating roller is fixed in position but can rotate. The automatic rotating device is used for driving the slurry in the fixed hopper and transferring the slurry to a base material, and the automatic rotating speed can be adjusted so as to change the thickness of the slurry coated on the base material; the comma roller can only move in the up-down direction. A linear knife edge and a standby linear knife edge are processed on the comma roller and used for controlling the size of a slit between the comma roller and the coating roller so as to change the coating surface density; the back roller can rotate and reciprocate towards the axis direction of the coating roller. The coating roller is used for driving the base material to move forwards at a constant speed, pressing the base material on the coating roller, and moving opposite to the coating roller during coating to transfer the slurry to the base material.

Furthermore, the substrate in the unwinding device is connected with the drying box and the deviation rectifying and winding device through the coding roller, the back roller and the discharging carrier roller.

Furthermore, an optical fiber sensor is arranged on the other side of the base material corresponding to the coding stick.

Because scribble roller department and increased the white scraper that leaves, in coating process, need begin to leave the position of white, leave the white scraper and paste the coating roller under servo motor and ball screw's drive, along with the rotation of coating roller, thick liquids are scraped by leaving the white scraper, and pump sending back to in the fixed hopper, end until leaving the white region, servo motor counter rotation, leave the white scraper and scribble the roller separation, this in-process back of the body roller is laminated on scribbling the roller always, the production of leaving white no longer need be kneaded by the back of the body roller with the action of flicking, coating area and leaving the white regional direct production on scribbling the roller, consequently, bring following three benefits:

1. the coating head does not have the action that the back roll is close to the coating roll when the coating area starts, so the thickness of the slurry on the coating roll is kept uniform, the abnormal area of the coating head does not have obvious bulge, and the speed of the coating roll does not need to be specially controlled;

2. when the coating area is finished, the coating tail has no action that the back roll is far away from the coating roll, the coating roll is directly provided with a white area, and no fluid slurry exists, so that the slurry coated on the coated substrate cannot be pulled by the slurry on the coating roll, and the abnormal area of the coating tail has no obvious trailing and thickness abnormality;

3. the residual white scraper directly scrapes the slurry in the coating residual white area and pumps the slurry back into the fixed hopper, so that residual slurry in the residual white area is not left on the coating roller after coating, a residual material scraper and a reclaimed material receiving tray are not needed, the slurry is saved, and the workload of operators is reduced.

Drawings

In order to illustrate the embodiments of the present invention more clearly, the drawings that are needed in the description of the embodiments will be briefly described below, and it is obvious that the drawings in the description below are only some embodiments of the present invention, and that other drawings can be obtained by those skilled in the art without inventive work.

FIG. 1 is a schematic structural view of a prior art transfer coating apparatus;

FIG. 2 is a schematic structural view of a transfer coating apparatus with a white coating roller according to the present invention;

description of reference numerals:

1. the coating machine comprises a coating roller, 2.comma rollers, 2-1 comma roller linear knife edges, 2-2 comma roller standby linear knife edges, 3.a back roller, 4.a fixed hopper, 1-5 residual material scrapers, 1-6 residual slurry, 1-7 recovered material receiving discs, 8.an optical fiber sensor, 7.a coding roller, 9.a discharge carrier roller, 1-11 coating tail abnormal areas, 1-12 coating head abnormal areas, 12 a drying box and deviation-correcting winding device, 13.an unwinding device, 2-5 white-left scrapers, 2-6 slurry recovery pipes, 2-10 coating head areas and 2-11 coating tail areas.

Detailed Description

The technical solutions in the embodiments of the present invention will be described clearly and completely with reference to the accompanying drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments in the present invention, all other embodiments obtained by a person skilled in the art without any creative effort belong to the protection scope of the present invention.

The structure and operation of the present invention will be described in further detail with reference to the accompanying drawings.

As shown in fig. 2, the roll-coating type transfer coating apparatus includes an unwinding device 13, an intermediate coating device, a drying oven, and a deviation-correcting winding device 12 in sequence according to the substrate driving direction.

The function of the unwinding device 13 is to smoothly transfer the substrate (usually copper foil as anode and aluminum foil as cathode in the production of lithium batteries) not coated with the slurry to the intermediate coating device. The stable speed, the stable tension and the fixed tape-moving direction are provided for the base material through unreeling deviation correction and unreeling tension control, and the base material is prevented from being suddenly fast or suddenly slow or from being directionally deflected in the slurry coating process to cause the slurry not to be coated in a specified area.

The drying oven and the deviation rectifying and winding device 12 have the functions of sending the pole piece coated with the slurry into an oven for heating and blast drying, removing the solvent in the slurry, and leaving the active substance adhered on the base material to form a dried pole piece. And after drying, coiling the coil on a coiling shaft in a fixed direction at a stable speed by coiling deviation rectification and coiling tension control, and waiting for the next process.

The coating device has the functions of uniformly and reliably coating the pre-processed slurry on the base material conveyed by the unwinding device and driving the base material coated with the slurry to enter a rear drying box and a deviation rectifying and winding device. There is a need to stably control important parameters such as thickness and face density of the coating material and head-to-tail thinning.

The coating device comprises a coating roller 1 and a back roller 3, a comma roller 2 is arranged right above the coating roller 1, a fixed hopper 4 is arranged on the left upper side of the coating roller 1, a blank scraper 2-5 is arranged on the right upper side of the coating roller 1, a storage cavity (not shown in the figure) is arranged on the blank scraper 2-5 and is communicated with a slurry recovery pipe 2-6, a delivery pump (not shown in the figure) is arranged on the slurry recovery pipe 2-6, and the discharge end of the slurry recovery pipe 2-6 is communicated with a feed inlet of the fixed hopper 4.

As an improvement of the invention, a white residue scraper 2-5 and a slurry recovery pipe 2-6 which can scrape the slurry on the coating roller and can pump the slurry back to the fixed hopper are additionally arranged. Because the thick liquids in the margin region are returned to the fixed hopper by the margin scraper and the pump of thick liquids recovery tube, consequently do not have remaining thick liquids on the back roll back-coating roller, consequently need not to use clout scraper and reclaimed materials flange, avoided scraper to change and thick liquids extravagant.

Further, the coating roller 1, the comma roller 2 and the back roller 3 are respectively connected with a driving device, the coating roller is fixed in position but can rotate, and is used for driving the slurry in the fixed hopper and transferring the slurry onto a base material, and the rotation speed can be adjusted so as to change the thickness of the slurry coated on the base material; the comma roller can only move in the up-down direction. A comma roller linear knife edge 2-1 and a comma roller standby linear knife edge 2-2 are processed on the comma roller 2 and used for controlling the size of a slit between the comma roller and a coating roller so as to change the coating surface density; the back roller can rotate and reciprocate towards the axis direction of the coating roller. The coating roller is used for driving the base material to move forwards at a constant speed, pressing the base material on the coating roller, and moving opposite to the coating roller during coating to transfer the slurry to the base material.

Further, the base material in the unreeling device 13 is connected with the drying box and the deviation rectifying and reeling device 12 through the coding roller 7, the back roller 3 and the discharging carrier roller 9; further, an optical fiber sensor 8 is provided on the other side of the base material corresponding to the encoder roller 7.

The specific operation steps are as follows:

firstly, mounting accessories and debugging a benchmark:

an acceptable substrate is prepared before coating begins. And (5) starting to install the fixed hopper 4 and then correcting the reference knife edge. And (3) moving the comma roller 2 downwards to be close to the coating roller 1 to form a slit knife edge, then calibrating the slit knife edge by using a feeler gauge with standard thickness, and enabling the knife edges on the left side and the right side to be consistent in height to finish the correction of the reference knife edge. And then, carrying out kneading degree calibration on the back roller 3, separating the back roller 3 from the coating roller 1, cutting two strip-shaped base materials, respectively placing the two strip-shaped base materials in roll gaps on two sides, then pushing the back roller to clamp the coating roller, slightly pulling the base materials, reducing the distance for pushing the back roller if the base materials cannot be pulled, increasing the distance for pushing the back roller if the base materials are not clamped until the base materials are just clamped and cannot be pulled, setting the position as the clamping position of the back roller at the moment, and finishing the kneading degree calibration of the back roller. Pushing the white remaining scraper 2-5 to be tightly attached to the coating roller 1, and checking whether the two sides of the knife edge are uniformly attached to the surface of the coating roller.

Second, mounting base material

The method comprises the steps of installing a substrate on an unreeling device before coating, enabling one surface of the substrate to be coated to face upwards, locating after determining the tape-moving direction, drawing the substrate to the coating device after locating, sequentially passing through a coding roller 7, a back roller 3 and a discharging carrier roller 9, then passing through a drying box to a deviation-rectifying reeling device and reeling on a reeling shaft of the reeling device, finally adjusting the substrate tension and the tape-moving direction to enable the substrate to be flat and wrinkle-free, and completing substrate installation.

Thirdly, debugging the areal density

And transferring the prepared slurry into a fixed hopper 4, and rotating the coating roller 1 to drive the slurry to be attached to the surface of the coating roller to pass through a slit blade. Parameters such as comma roller height, coating length, white residue and the like are set, coating is started by clicking, a drying oven is started for blast heating, a servo motor pushes a back roller 3 to be attached to a coating roller and starts to rotate, and at the moment, slurry attached to the surface of the coating roller is transferred to a base material due to friction.

Firstly, trial coating is carried out for a certain distance, then the pole piece is sent into a drying oven to be dried, and then a sample is taken from the dried pole piece and weighed. And measuring the weight of the pole piece in unit area, calculating the weight of the attached active substance, comparing the weight with the standard weight of the process requirement, and debugging other parameters such as coating length, head and tail thinning and the like if the weight meets the requirement. And if the weight does not meet the requirement, changing the height of the comma roller to adjust the size of the slit knife edge, sampling and weighing after trying to coat for a section again until the weight meets the process requirement, and starting to debug the coating length and head and tail thinning parameters.

Fourthly, debugging head and tail thinning parameters

The head and tail thinning parameters are adjusted by combining the pushing speed of the white leaving scraper and the speed ratio of the coating roller.

Taking samples of the head and the tail of the dried pole piece respectively, and measuring the difference between the thickness of the head and the tail and a normal area by using a micrometer, wherein the normal area is slightly smaller than the normal area (such as 2-10. coating the head area and 2-11. coating the tail area). If the thickness of the head is larger than the process requirement, the speed of the white-remaining scraper far away from the coating roller can be reduced or the head speed ratio of the coating roller and the back roller can be improved, otherwise, the speed of the white-remaining scraper far away from the coating roller can be improved or the head speed ratio of the coating roller and the back roller can be reduced; if the thickness of the tail part is larger than the process requirement, the speed of the white leaving scraper attaching to the coating roller can be reduced; if the thickness of the tail part is smaller than the process requirement, the speed of the white leaving scraper clinging to the coating roller can be improved.

Fifthly, adjusting the coating length and the blank length

The length adjustment is adjusted by changing the time for which the doctor blade is close to and away from the coating roller.

And measuring the coating length and the length of the white left after drying, and directly debugging the head and tail thinning parameters if the process requirements are met. If the coating length is less than the process requirement, the time for the white leaving scraper to cling to the coating roller is lagged, and if the coating length is greater than the process requirement, the time for the white leaving scraper to cling to the coating roller is advanced. And if the length of the blank is less than the process requirement, delaying the time of the blank scraper far away from the coating roller, otherwise, advancing the time of the blank scraper far away from the coating roller. After several attempts, the surface density, the head and tail thinning, the coating length and the white length all meet the process requirements.

The present invention is not exhaustive and is well known to those skilled in the art.

The above description is only a preferred embodiment of the present invention, and should not be taken as limiting the invention, and any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. The utility model provides a scribble roller and leave white formula and shift coating equipment, includes unwinding device (13), drying cabinet and coiling mechanism (12), the coating unit of rectifying, coating unit is equipped with comma roller (2) including scribbling roller (1) and backing roll (3) directly over scribbling roller (1), scribbles roller (1) upper left side and is equipped with fixed hopper (4), its characterized in that: the upper right side of the coating roller (1) is provided with a white scraper (2-5), the white scraper (2-5) is provided with a storage cavity, the storage cavity is communicated with a slurry recovery pipe (2-6), and the discharge end of the slurry recovery pipe (2-6) is communicated with the feed inlet of the fixed hopper (4).

2. The roll-on-white transfer coating apparatus of claim 1, characterized in that: the back roll (3) is arranged at the right lower part of the coating roll (1).

3. The roll-on-white transfer coating apparatus of claim 1, characterized in that: the white scraper (2-5) is connected with a driving device, and the driving device comprises a servo motor and a ball screw.

4. The roll-on-white transfer coating apparatus of claim 1, characterized in that: and a delivery pump is arranged on the slurry recovery pipe (2-6).

5. The roll-on-white transfer coating apparatus of claim 1, characterized in that: the comma roller (2) is provided with a linear knife edge (2-1) and a standby linear knife edge (2-2).

6. The roll-on-white transfer coating apparatus of claim 1, characterized in that: the coating roller (1), the comma roller (2) and the back roller (3) are respectively connected with a driving device.

7. The roll-on-white transfer coating apparatus of claim 1, characterized in that: the base material in the unreeling device (13) is connected with the drying box and the deviation rectifying and reeling device (12) through the coding roller (7), the back roller (3) and the discharging carrier roller (11).

8. The roll-on-white transfer coating apparatus of claim 7, wherein: and an optical fiber sensor (8) is arranged on the other side of the base material corresponding to the coding stick (7).