An automated intermittent precision coating system

Abstract

This invention discloses an automated intermittent precision coating system, comprising a coating die, a substrate conveying mechanism, a coating valve, and a residue removal mechanism. The substrate conveying mechanism drives the substrate to move intermittently, and during each pause, drives the substrate to perform a retraction motion. This retraction motion is opposite to the coating direction, used to eliminate transmission backlash. The retraction stroke length is 0.2mm to 10mm. This invention links the retraction motion with the residue removal operation, eliminating the need for a separate drive power source, simplifying the system structure and reducing equipment costs. Furthermore, it improves coating accuracy and system adaptability by automatically adjusting the coating valve closing sequence according to the slurry viscosity through a phase adjustment mechanism, balancing removal efficiency and quality through mechanical coupling transmission, and achieving adaptive design through a stroke adjustment mechanism.

Description

Technical Field

[0001] This invention relates to the field of coating equipment technology, and in particular to an automated intermittent precision coating system. Background Technology

[0002] In precision coating processes such as lithium battery electrodes and optical thin films, intermittent coating is carried out by a substrate conveying mechanism that drives the substrate to move intermittently. During each pause, the coating die applies slurry to the surface of the substrate. During each intermittent pause, the substrate conveying mechanism drives the substrate to perform a retraction action. The direction of the retraction action is opposite to the coating movement direction, which is used to eliminate transmission gaps.

[0003] However, in the prior art, the residual slurry at the edge of the coating die lip partially solidifies during the intermittent period, causing uneven thickness or scratching the substrate when coating again; and the existing elimination solutions usually set up independent scraper drive devices or vacuum suction devices, both of which require independent drive power sources and independent control timing, resulting in complex structure and increased cost. Meanwhile, the time difference between the closing time of the coating valve and the starting time of the substrate retraction action is fixed, which cannot adapt to slurries of different viscosities. High viscosity slurries are prone to dripping and leaving residues, while low viscosity slurries cannot utilize the retraction suction effect. In addition, the constant speed elimination motion is prone to spreading in the wetted area, and it cannot remove stubborn residues at high speeds. Efficiency and quality are difficult to balance, and manual adjustment is required when changing coating dies of different widths, which takes a long time to debug.

[0004] Therefore, there is an urgent need for an automated intermittent precision coating system that links the retraction action with the residue removal operation, requires no independent power source, adapts to different slurries, and balances efficiency and quality. Summary of the Invention

[0005] The purpose of this invention is to provide an automated intermittent precision coating system to solve the problems mentioned in the background section.

[0006] The present invention aims to provide an automated intermittent precision coating system to solve the technical problems in the prior art, such as decreased accuracy of coating start position, poor uniformity of coating thickness, and increased equipment failure rate caused by residual slurry at the edge of the coating die lip.

[0007] To achieve the above objectives, the present invention adopts the following technical solution: An automated intermittent precision coating system includes a coating die, a substrate conveying mechanism, a coating valve, and a residue removal mechanism.

[0008] The coating die is used to apply a slurry to the surface of a substrate.

[0009] The substrate conveying mechanism is used to drive the substrate to move intermittently, including a drive roller; wherein each time there is an intermittent pause, the substrate conveying mechanism drives the substrate to perform a retraction action, the direction of which is opposite to the coating travel direction, in order to eliminate transmission gaps; the stroke length of the retraction action is 0.2mm to 10mm.

[0010] The coating valve is used to control the slurry supply.

[0011] And a residue removal mechanism, wherein the residue removal mechanism is mechanically coupled to the drive roller of the substrate conveying mechanism through a one-way transmission assembly, the one-way transmission assembly including a one-way clutch fixed to the shaft end of the drive roller and a gear and rack mechanism connected to the output end of the one-way clutch; The residue removal mechanism includes a scraper or a suction port; When the substrate performs a retraction action, the drive roller rotates in the reverse direction, the one-way clutch engages and transmits torque to the residue removal mechanism via the gear and rack mechanism, driving the residue removal mechanism to perform a removal operation on the lip edge of the coating die head; when the drive roller rotates in the forward direction, the one-way clutch idles, and the residue removal mechanism is disconnected from the drive roller. The unidirectional transmission assembly has a total transmission ratio, and the ratio of the elimination stroke of the residue elimination mechanism to the retraction stroke of the substrate is determined by this total transmission ratio, which is 5 to 40.

[0012] In this embodiment, the total transmission ratio is achieved by connecting a stroke amplification mechanism and a gear and rack mechanism in series. The transmission ratio of the stroke amplification mechanism is 10, and the tooth ratio (number of teeth on the driven gear / number of teeth on the driving gear) of the gear and rack mechanism is 0.5 to 4.0. Multiplying the two together yields a total transmission ratio of 5 to 40. Those skilled in the art can also achieve the same total transmission ratio using other transmission layouts such as worm gears, belt drives, or planetary gear mechanisms, and are not limited to the series gear structure described in this embodiment.

[0013] By adopting the above technical solution, the retraction motion of the substrate conveying mechanism is mechanically coupled with the residue removal mechanism. This allows the residue removal operation to be driven by the retraction motion itself, eliminating the need for a separate drive power source for the residue removal mechanism, thus simplifying the system structure and reducing equipment costs. Furthermore, since the retraction motion is a necessary action in the intermittent coating process, mechanically coupling the residue removal mechanism with this retraction motion achieves automatic removal of residual slurry at the lip without increasing additional processing time, thereby improving coating efficiency.

[0014] Furthermore, the residue removal mechanism includes a scraper, and the removal operation includes: driving the scraper to move along the edge of the lip to scrape the residual slurry away from the edge of the lip.

[0015] The scraper employs an elastic scraper structure, which allows it to adapt to the microscopic unevenness of the lip surface when adhering to the lip edge, avoiding damage to the lip edge caused by rigid contact, while ensuring effective removal of semi-cured or cured residual paste.

[0016] Furthermore, the residue removal mechanism includes a suction port, and the removal operation includes: driving the suction port to move along the edge of the lip to suck the residual slurry into the recovery container.

[0017] The negative pressure suction method is used to remove the fluid residual slurry, thereby avoiding mechanical wear on the lip edge by the scraper. At the same time, the recovered slurry can be reused, reducing material loss.

[0018] Furthermore, the one-way transmission assembly includes a one-way clutch, which is mounted on the shaft end of the drive roller. The one-way clutch engages and outputs torque only when the drive roller performs a retraction action, and idles during forward rotation. The output torque is transmitted to the residue elimination mechanism through a transmission component.

[0019] A one-way clutch is used to achieve mechanical coupling, thereby automatically identifying the coating travel and retraction states by utilizing the difference in the forward and reverse rotation directions of the drive roller. The action triggering and release of the residue removal mechanism can be realized without additional sensors or control signals, which simplifies the control logic and improves the system reliability.

[0020] Furthermore, the direction of motion of the residue removal mechanism is perpendicular to the direction of substrate retraction; the unidirectional transmission assembly includes a gear and rack mechanism, which converts the rotational motion of the drive roller into the linear reciprocating motion of the scraper or the suction port, and the direction of the linear reciprocating motion is along the width direction of the lip edge.

[0021] By employing a gear and rack mechanism, the rotational motion is converted into a linear reciprocating motion along the width of the lip edge. This eliminates residue along the entire width of the lip without altering the original motion layout of the substrate conveying mechanism, thus expanding the functional reuse range of the retraction action.

[0022] Furthermore, the gear and rack mechanism includes a driving gear, a driven gear, and a rack. The driving gear is fixedly connected to the transmission shaft, which is connected to the output end of the one-way clutch via a stroke amplification mechanism. The driven gear meshes with the driving gear, and the rack meshes with the driven gear. The rack is fixedly connected to the bracket of the residue elimination mechanism, and the rack moves linearly along the width direction of the lip edge.

[0023] Furthermore, it also includes a stroke adjustment mechanism, which includes a replaceable driven gear. By replacing the driven gear with one that has a different number of teeth, the transmission ratio of the gear and rack mechanism can be changed, thereby changing the elimination stroke length so that the moving distance of the scraper or suction port matches the lip edge width.

[0024] The elimination stroke is adjusted by using a replaceable driven gear structure. The transmission ratio and elimination stroke can be changed by replacing the gear. The elimination stroke can be matched with the lip width without the need for a complicated adjustment mechanism. This avoids problems such as incomplete elimination or mechanism interference caused by changes in lip specifications, and greatly shortens the equipment changeover and debugging time.

[0025] Furthermore, it also includes a slurry recovery tank, which is located below the lip of the coating die head; the recovery tank is linked with the residue removal mechanism, and when the residue removal mechanism performs the removal operation, the recovery tank is driven by the same retraction action to swing directly below the lip to receive the scraped or sucked residual slurry.

[0026] The slurry recovery tank and the residue removal mechanism are driven together by a single retraction action. The transmission path of this retraction action is as follows: the drive roller rotates in the opposite direction until the one-way clutch engages, the drive shaft rotates, the driving gear rotates, the driven gear rotates, and the rack moves along the width of the lip. The rack's movement simultaneously triggers two actions: first, it drives the scraper or suction port to perform the removal operation; second, the fork at the end of the rack pushes the pin on the swing arm, causing the recovery tank to swing directly below the lip to collect residual slurry. Therefore, the slurry recovery tank's swing and the residue removal mechanism's removal operation share the same power source and the same timing trigger signal, eliminating the need for a separate drive device and control logic for the slurry recovery tank, further simplifying the system structure and reducing equipment costs.

[0027] Furthermore, the time difference between the closing time of the coating valve and the starting time of the substrate retraction action is configured to be adjustable; the time difference is defined as the closing time of the coating valve minus the starting time of the substrate retraction. When the time difference is less than zero, the coating valve closes first and then the substrate retracts; when the time difference is greater than zero, the substrate retracts first and then the coating valve closes. The system also includes a phase adjustment mechanism, which comprises a viscosity signal acquisition module, a timing calculation module, and a phase execution module connected in sequence. The viscosity signal acquisition module is used to detect the viscosity of the slurry in real time and output a viscosity signal. The timing calculation module receives the viscosity signal, calculates the time difference setting value according to a preset viscosity-time mapping relationship, and outputs a time difference command. The phase execution module receives the time difference command and adjusts the closing time of the coating valve. The time difference is automatically adjusted by the phase adjustment mechanism based on the slurry viscosity.

[0028] The system automatically adjusts the time difference between the closing time of the coating valve and the starting time of the retraction based on the viscosity of the slurry, thereby adaptively selecting the optimal timing combination for slurries of different viscosities. This avoids additional residue under high viscosity conditions and reduces residue by utilizing the retraction suction effect under low viscosity conditions, significantly improving the system's adaptability to different slurry systems.

[0029] Furthermore, it also includes a detection unit for detecting the thickness or distribution of residual slurry at the edge of the coating die lip; the detection unit is connected to an alarm unit, and when the detected residual slurry thickness exceeds a preset threshold, the alarm unit issues an alarm signal to prompt the operator to replace the replaceable driven gear or adjust the retraction stroke length.

[0030] A monitoring strategy combining detection and alarm units is adopted to promptly detect abnormalities such as incomplete residue removal, prompting operators to intervene manually and avoid coating quality degradation due to residue accumulation. At the same time, the removal effect can be monitored at a relatively low hardware cost.

[0031] Furthermore, the recycling tank is mounted below the coating die head via a swing arm, which is connected to a tension spring. The preload of the tension spring keeps the recycling tank in an abutment position. The rack of the residue removal mechanism has a fork at its end. The fork is an L-shaped plate with its horizontal arm extending toward the slurry recycling tank. The swing arm has an elongated groove, the length of which extends along the moving direction of the rack, and the length of the groove is not less than 80% of the rack's travel. When the rack moves toward the end, the horizontal arm of the fork enters the groove and pushes the sidewall of the groove, causing the recycling tank to swing to directly below the lip at the beginning of the removal operation and remain in the receiving position throughout the sliding process of the fork within the groove. When the rack returns to the starting end, the fork separates from the groove, and the recycling tank returns to the abutment position under the action of the tension spring.

[0032] The system employs a mechanical linkage structure that combines a fork, a slot, and a tension spring. This allows the rack to automatically trigger the swinging in and out of the recycling bin using its linear motion. No additional drive device or control logic is required, which enables automatic switching of the recycling bin's position, simplifies the system structure, and improves operational reliability. Attached Figure Description

[0033] Figure 1 This is a schematic diagram of the system framework structure of the present invention. Detailed Implementation

[0034] The technical solution of the present invention will be clearly and completely described below with reference to the embodiments. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0035] Please see Figure 1 This invention provides an automated intermittent precision coating system, comprising a coating die, a substrate conveying mechanism, a coating valve, a residue removal mechanism, and a control unit. The control unit is a programmable logic controller (PLC), which is connected to the driver of the servo motor via a pulse signal interface, to the control terminal of the solid-state relay via a digital output interface, and to the output terminal of the online viscometer via an analog input interface.

[0036] The coating die head is used to apply slurry to the surface of a substrate, and its inlet end is connected to the slurry supply pipeline. The coating die head is a slit-type coating die head, consisting of an upper lip plate and a lower lip plate. A slit-shaped slurry flow channel is formed between the upper and lower lip plates, and the outlet end of the slurry flow channel constitutes a lip. The edges of the lips of the upper and lower lip plates are precision ground, with a surface roughness Ra not exceeding 0.4 μm. The opening width of the lip is 0.05 mm to 0.5 mm, and this opening width can be finely adjusted using an adjusting bolt with an adjustment accuracy of 0.01 mm. A coating gap is formed between the lip of the coating die head and the substrate surface. The size of this coating gap directly affects the coating thickness and is typically set to 0.1 mm to 0.3 mm.

[0037] The use of a slit-type coating die and precision grinding of the lip edge ensures the uniformity and accuracy of the slurry coating, while reducing the micro-roughness of the lip edge and reducing the adhesion of residual slurry, thus providing favorable conditions for subsequent residue removal operations.

[0038] The substrate conveying mechanism, used to drive the substrate intermittently, includes a drive roller, a tension roller, a guide roller, and a servo motor. The drive roller and the servo motor are connected by a reducer with a reduction ratio of 10:1 to 50:1. The servo motor has a built-in encoder with a resolution of over 10,000 pulses per revolution, thereby ensuring that the angular position control accuracy of the drive roller reaches below 0.036 degrees.

[0039] The drive roller is covered with a rubber layer with a Shore A60 to A80 hardness and a thickness of 5 mm to 15 mm. Spiral grooves are formed on the surface of the rubber layer, with a groove depth of 0.5 mm to 2 mm and a groove spacing of 5 mm to 20 mm. The drive roller has a diameter of 100 mm to 200 mm. The tension roller and the drive roller are arranged sequentially along the substrate's travel direction to maintain constant substrate tension.

[0040] Tension sensors are installed at both ends of the tension roller, with a tension detection range of 0N to 500N and a detection accuracy of ±0.5% of full scale. A guide roller is arranged on the substrate inlet side of the drive roller to guide the substrate into the covering area of ​​the drive roller. The servo motor is electrically connected to the control unit and receives control signals output by the control unit to achieve intermittent travel control.

[0041] The system employs a servo motor with a built-in high-resolution encoder and a reducer to precisely control the angular position of the drive roller, ensuring positioning accuracy during intermittent travel. At the same time, the rubber coating and spiral groove design increase the friction with the substrate, preventing slippage during travel and ensuring the stroke accuracy of the retraction action.

[0042] During each intermittent pause, the servo motor receives a reverse control signal from the control unit, driving the drive roller to rotate in the opposite direction. This causes the substrate to perform a retraction motion, the direction of which is opposite to the coating travel direction, to eliminate transmission backlash. The retraction stroke length is 0.2mm to 10mm. The basis for setting this retraction stroke length is as follows: When the retraction stroke length is less than 0.2 mm, it is insufficient to eliminate transmission backlash, which includes the gear meshing clearance of the reducer, the elastic deformation clearance of the coupling, and the microscopic slippage clearance between the rubber layer and the substrate. When the retraction stroke length is greater than 10 mm, excessive retraction of the substrate can cause wrinkling or peeling of the coated slurry edges. In this embodiment, the preferred retraction stroke length is 2 mm, which is suitable for typical working conditions with substrate tension of 50 N to 150 N and rubber layer hardness of Shore A70. When the substrate tension is high, the retraction stroke length can be adjusted to 0.5 mm to 1 mm to ensure the elimination of transmission backlash while avoiding excessive relaxation of the substrate.

[0043] By employing a retraction stroke length range of 0.2mm to 10mm, a balance is achieved between eliminating transmission backlash and avoiding substrate damage. At the same time, the retraction stroke is precisely controlled by a servo motor to ensure the consistency and repeatability of each retraction action, thereby improving the accuracy of the coating start position.

[0044] The coating valve, electrically connected to the control unit, controls the slurry supply and is positioned between the slurry supply pipeline and the inlet end of the coating die. It controls the on / off state of the slurry supply based on the switching signal from the control unit. The coating valve is an electromagnetic shut-off valve with a response time not exceeding 50ms. The valve body is made of 316L stainless steel, and the sealing material is polytetrafluoroethylene (PTFE). The coil of the electromagnetic shut-off valve is connected to a solid-state relay. The control terminal of the solid-state relay receives the switching signal output from the control unit, opening the valve by controlling the energization of the coil and closing the valve by controlling the de-energization of the coil.

[0045] An electromagnetic shut-off valve with a response time of no more than 50ms is used in conjunction with a solid-state relay for control, thereby quickly responding to the switching signals of the control unit, accurately controlling the on and off time of slurry supply, reducing slurry dripping residue caused by valve response delay, and improving the clarity of coating edges.

[0046] The residue removal mechanism is mechanically coupled to the retraction action of the substrate conveying mechanism, and includes a scraper or a suction port. The residue removal mechanism is located on the outer side of the coating die lip edge. When the substrate retracts, the residue removal mechanism is driven by this retraction action to remove residual slurry from the coating die lip edge. The ratio of the removal stroke of the residue removal mechanism to the retraction stroke of the substrate is determined by the total transmission ratio of the unidirectional transmission assembly, which is 5–40. The retraction stroke is the linear displacement of the substrate during the retraction action, determined by the reverse rotation angle of the drive roller controlled by the servo motor; the removal stroke is the linear displacement of the scraper or suction port along the width direction of the lip edge, converted from the reverse rotation motion of the drive roller by the gear and rack mechanism.

[0047] It should be clarified that the total transmission ratio mentioned in this application refers to the transmission ratio of the entire mechanically coupled transmission chain from the end of the drive roller shaft to the end of the residue elimination mechanism, and is defined as the ratio of the elimination stroke to the retraction stroke. This total transmission ratio consists of two parts connected in series: one is the transmission ratio of the stroke amplification mechanism (fixed to 10 in this embodiment, that is, the rotational speed of the transmission shaft is 10 times the rotational speed of the drive roller shaft), and the other is the tooth ratio of the gear and rack mechanism (defined as the ratio of the number of teeth of the driven gear to the number of teeth of the driving gear).

[0048] Specifically, the gear-rack mechanism has a tooth ratio of 0.5 to 4.0. This tooth ratio range is set based on the following: when the tooth ratio is less than 0.5, the driven gear has too few teeth, and the rack displacement is insufficient to cover the full width of the lip; when the tooth ratio is greater than 4.0, the rack displacement is too large, and the scraper or suction port may exceed the edge of the lip or interfere with other components of the coating die.

[0049] In this embodiment, the transmission ratio of the stroke amplification mechanism is 10, the number of teeth of the driving gear is 20, the number of teeth of the driven gear is 40, and the tooth ratio of the gear and rack mechanism is 40 / 20 = 2.0. Multiplying these two values, we get the total mechanical coupling transmission ratio = 10 × 2.0 = 20. Correspondingly, when the tooth ratio of the gear and rack is varied from 0.5 to 4.0 by changing the driven gear (10 to 80 teeth), the total transmission ratio varies from 5 to 40. Therefore, when the retraction stroke is 2mm, the actual elimination stroke of the scraper or suction port at the end of the rack is 10mm to 80mm (i.e., 2mm retraction stroke × total transmission ratio 5 to 40), and this total transmission ratio range covers the elimination requirements of different lip widths.

[0050] By employing a total mechanical coupling transmission ratio ranging from 5 to 40, a balance is achieved between eliminating coverage and ensuring mechanical safety. Simultaneously, the power of the retraction action is reused for residue elimination through mechanical coupling, eliminating the need for an independent power source, simplifying the system structure, and reducing equipment costs.

[0051] The one-way transmission assembly includes a one-way clutch, a drive shaft, and a gear and rack mechanism, which transmits the reverse rotation torque of the drive roller to the residue elimination mechanism.

[0052] In this embodiment, the one-way clutch is a roller-type one-way clutch. Its inner ring is fixedly connected to the shaft of the drive roller via a flat key, and its outer ring is connected to the input end of a stroke amplification mechanism via a spline. The stroke amplification mechanism is a two-stage speed-increasing gear pair. The first-stage driving gear has 20 teeth and the first-stage driven gear has 40 teeth (speed ratio 2.0), the second-stage driving gear has 20 teeth and the second-stage driven gear has 25 teeth (speed ratio 1.25), with a total speed ratio of 2.5; or the second-stage driving gear has 16 teeth and the second-stage driven gear has 40 teeth (speed ratio 2.5), with a total speed ratio of 5.0; or a worm gear and gear combination is used to achieve a total speed ratio of 10. In this embodiment, by selecting the second-stage driving gear 16 and driven gear 40, the total speed ratio is 5.0, and with a gear-rack tooth ratio of 2.0, the total transmission ratio is 10. When the gear-rack tooth ratio varies within the range of 0.5 to 4.0, the total transmission ratio varies accordingly within the range of 2.5 to 20. Those skilled in the art can also increase the number of transmission stages or use a planetary gear mechanism to achieve a transmission ratio of 10 for the stroke amplification mechanism, thereby extending the total transmission ratio range to 5 to 40.

[0053] The driving gear is fixedly connected to the outer ring of the one-way clutch, and the driven gear is fixedly connected to one end of the drive shaft via a spline. The drive shaft has a diameter of 15mm to 25mm, is made of 40Cr tempered steel, and has a torsional strength of not less than 600MPa. The drive shaft is mounted in a bearing housing via two deep groove ball bearings, the bearing housing being fixed to the side wall of the coating die. The span between the two bearings is 100mm to 150mm, with the bearing closer to the one-way clutch being the fixed end and the other bearing being the floating end to compensate for axial displacement caused by thermal expansion. The axis of the drive shaft is parallel to the edge of the lip, and the distance between the axis of the drive shaft and the axis of the drive roller shaft is 80mm to 120mm.

[0054] The direction recognition is achieved by using a roller-type one-way clutch, thereby automatically distinguishing between the coating travel state and the retraction state through mechanical structure. No additional sensors or control signals are required, which simplifies the control logic, eliminates the risk of sensor failure, and the response speed depends only on the mechanical engagement angle and is not limited by the control cycle, thus improving the system reliability.

[0055] The gear and rack mechanism includes a driving gear, a driven gear, and a rack. The driving gear is fixedly connected to the transmission shaft, which is connected to the output end of the one-way clutch via a stroke amplification mechanism. The driven gear meshes with the driving gear, and the rack meshes with the driven gear. The rack is fixedly connected to the bracket of the residue removal mechanism and moves linearly along the width direction of the lip edge. The rack is linearly guided by a rack guide seat, which is fixed to the side wall of the coating die. A guide groove is formed in the rack guide seat, and the rack is embedded in the guide groove and can slide linearly along the guide groove. The length of the guide groove is not less than the stroke of the rack, and the guide groove and the rack are in clearance fit, with a clearance of 0.05mm to 0.2mm.

[0056] In this embodiment, the driving gear has 20 teeth, the driven gear has 40 teeth, and the gear-rack mechanism has a tooth ratio of 2.0 (40 teeth on the driven gear / 20 teeth on the driving gear). By replacing the driven gear with a different number of teeth, this tooth ratio can be adjusted within the range of 0.5 to 4.0, corresponding to a total transmission ratio of 5 to 40, to adapt to different lip widths.

[0057] The gear and rack mechanism converts the rotational motion of the drive shaft into the linear motion of the rack, thereby converting the retracting rotational motion of the drive roller into the elimination motion along the width of the lip. The transmission ratio is constant and precise, ensuring a stable ratio between the elimination stroke and the retracting stroke. At the same time, the gear transmission is highly efficient and has a fast response, making it suitable for high-frequency start-stop conditions in intermittent coating.

[0058] After the retraction action is completed, the drive roller stops rotating in the reverse direction, and the one-way clutch is unlocked. A return spring is provided between the bracket of the residue removal mechanism and the coating die head. After the one-way clutch is unlocked, the residue removal mechanism is driven to return from the termination end to the starting end. The return spring is a tension spring with an elastic coefficient of 0.5N / mm to 5N / mm, thereby ensuring that the residue removal mechanism can reliably reset and that the reset force does not cause deformation of the mechanism.

[0059] The automatic reset of the residue removal mechanism is achieved by using a tension spring, which quickly returns the scraper or suction port to the starting position after the one-way clutch is unlocked, preparing for the next removal operation. At the same time, the elastic force of the tension spring does not interfere with the normal transmission of the gear rack, ensuring the smooth movement of the mechanism.

[0060] In this embodiment, the movement direction of the residue removal mechanism is perpendicular to the substrate retraction direction. The unidirectional transmission assembly includes a gear and rack mechanism, which converts the rotational motion of the drive roller into linear reciprocating motion of the scraper or suction port, the direction of which is along the width direction of the lip edge.

[0061] The rotational motion is converted into linear reciprocating motion along the width of the lip edge by using a gear and rack mechanism. This eliminates the residue in the full width of the lip without changing the original motion layout of the substrate conveying mechanism, expands the functional reuse range of the retraction action, and eliminates the need to arrange an additional linear drive module in the width of the lip.

[0062] In this embodiment, the residue removal mechanism includes a scraper. The scraper is a long, elastic scraper made of silicone or fluororubber, with a Shore A40 to A70 hardness, a thickness of 1 mm to 5 mm, and a width of 3 mm to 10 mm. The scraper is mounted on one end of the rack via a scraper bracket and moves along the width direction of the lip edge together with the rack. The scraper bracket includes a fixed arm and a swing arm. The fixed arm is fixed to the rack, and the swing arm is connected to the fixed arm via a hinge shaft, the axis of which is parallel to the lip edge. A torsion spring is provided between the swing arm and the fixed arm. The preload of the torsion spring maintains a contact pressure between the scraper and the lip edge, which is 0.1 N / cm to 1 N / cm.

[0063] The scraper employs an elastic scraper structure, which allows it to adapt to the microscopic unevenness of the lip surface when adhering to the lip edge, avoiding damage to the lip edge caused by rigid contact. At the same time, it ensures effective removal of semi-cured or cured residual slurry, extending the service life of the coating die.

[0064] The removal operation includes: driving the scraper to move along the edge of the lip to scrape the residual slurry away from the edge of the lip. The moving speed of the scraper is the same as the moving speed of the rack, the moving speed of the rack is determined by the rotational speed of the driven gear, the rotational speed of the driven gear is determined by the rotational speed of the driving gear, the rotational speed of the driving gear is determined by the rotational speed of the drive shaft, and the rotational speed of the drive shaft is determined by the rotational speed of the drive roller.

[0065] In another embodiment, the residue elimination mechanism includes a suction port. The suction port is a flat nozzle with an opening width of 2mm to 5mm and an opening length of 10mm to 30mm, the opening length matching the lip width. The suction port is connected to a vacuum pump via a flexible suction tube. The vacuum pump has a vacuum level of -0.02MPa to -0.08MPa. The exhaust end of the vacuum pump is connected to a recovery container, which is either the slurry recovery tank or a sealed storage tank independent of the slurry recovery tank. The storage tank has a volume of 1L to 10L and is equipped with a liquid level observation window and a drain valve. Preferably, the vacuum level is -0.05MPa, and the pumping rate is 5L / min to 50L / min.

[0066] The suction port is mounted on one end of the rack via a suction port bracket, and moves along the width direction of the lip edge together with the rack. The suction port bracket includes a fixed arm and a swing arm, and the swing arm is connected to the fixed arm via a hinge shaft. The installation angle of the suction port is 30 degrees to 60 degrees, preferably 45 degrees.

[0067] The negative pressure suction method is used to remove the residual slurry with good fluidity, thereby avoiding mechanical wear of the lip edge by the scraper. At the same time, the recovered slurry can be reused, reducing material loss. Moreover, the negative pressure suction method fundamentally eliminates the problem of spreading when coating, which is specifically designed for the fluidity characteristics of low viscosity slurry.

[0068] The elimination operation includes: driving the suction port to move along the edge of the lip to suck the residual slurry into the recovery container.

[0069] In this embodiment, a stroke adjustment mechanism is also included. The stroke adjustment mechanism includes a replaceable driven gear. By replacing the driven gear with one that has a different number of teeth, the transmission ratio of the gear and rack mechanism is changed, thereby changing the elimination stroke length so that the moving distance of the scraper or suction port matches the lip edge width.

[0070] The replaceable driven gear is connected to the driven gear shaft via a spline. The driven gear shaft is mounted to the side wall of the coating die head via bearings. To replace the driven gear, simply pull out the old driven gear and push the new driven gear into place along the spline.

[0071] Different driven gears have different numbers of teeth, thus providing different rack and pinion ratios and elimination strokes. The rack and pinion ratio is defined as the ratio of the number of teeth on the driven gear to the number of teeth on the driving gear (i.e., the tooth ratio). The correspondence between driven gear specifications and lip width is shown in the table below. The elimination stroke in the table is calculated based on a 2mm return stroke, a stroke amplification mechanism ratio of 10, and the rack and pinion tooth ratio.

[0072] When changing to a coating die head of different widths, the operator selects the corresponding driven gear according to the lip width to make the moving distance of the scraper or suction port match the lip edge width.

[0073] The elimination stroke is adjusted by using a replaceable driven gear structure. The transmission ratio and elimination stroke can be changed by replacing the gear. The elimination stroke can be matched with the lip width without the need for a complicated adjustment mechanism. This avoids problems such as incomplete elimination or mechanism interference caused by changes in lip specifications, and greatly shortens the equipment changeover and debugging time.

[0074] In this embodiment, a slurry recovery tank is also included, which is disposed below the lip of the coating die head. The recovery tank is linked to the residue removal mechanism. When the residue removal mechanism performs the removal operation, the recovery tank is driven by the same retracting motion to swing directly below the lip to receive the scraped or sucked-up residual slurry.

[0075] The slurry recovery tank is a long, narrow tank with a length not less than the width of the lip, a width of 20mm to 50mm, a depth of 10mm to 30mm, and a volume of 50mL to 500mL. The inner surface of the slurry recovery tank is coated with a polytetrafluoroethylene coating.

[0076] The slurry recovery tank with a polytetrafluoroethylene coating on the inner surface reduces the adhesion between the slurry and the tank wall, making it easier to clean and reuse the recovered slurry. At the same time, the long strip tank design ensures full coverage of the lip, preventing slurry dripping and leakage.

[0077] The slurry recovery tank is mounted below the coating die head via a recovery tank bracket. The recovery tank bracket includes a fixed support and a swing arm. The fixed support is fixed to the bottom of the coating die head, and the swing arm is connected to the fixed support via a hinge shaft, the axis of which is parallel to the edge of the lip. A tension spring is provided between the swing arm and the fixed support. The preload of the tension spring keeps the slurry recovery tank in a clearance position below the lip when no external force is applied. At this time, the vertical distance between the slurry recovery tank and the edge of the lip is 30mm to 50mm.

[0078] The swing arm structure with pre-tensioned tension springs keeps the recovery tank in a clearance position when there is no elimination operation, avoiding interference with the coating operation. During the elimination operation, it automatically swings into the receiving position, realizing automatic switching of the action without the need for additional position detection and control logic.

[0079] The recycling tank is linked to the residue removal mechanism. A fork, which is an L-shaped plate, is provided on the lower surface of the rack end, with its horizontal arm extending towards the slurry recycling tank. A long groove is provided on the swing arm, with its length extending along the moving direction of the rack, and the length of the groove is not less than 80% of the rack's stroke. When the residue removal mechanism performs the removal operation, the rack moves towards its end, and the horizontal arm of the fork enters the groove at the beginning of its stroke and pushes the side wall of the groove, causing the swing arm to swing around the hinge axis against the preload of the tension spring. The slurry recycling tank then swings to directly below the lip at the beginning of the removal operation and remains in the receiving position throughout the entire process of the fork sliding within the groove. The swing angle of the recycling tank is 30 degrees to 90 degrees, preferably 60 degrees. When swinging to the receiving position, the vertical distance between the upper edge of the slurry recycling tank and the edge of the lip is 2 mm to 10 mm, thereby avoiding slurry splashing during the receiving process.

[0080] After the elimination operation is completed, the servo motor stops rotating in reverse, the one-way clutch unlocks, and the rack returns to the starting end under the action of the return spring. The shift fork returns with the rack, the horizontal arm of the shift fork separates from the shift groove, the swing arm returns to the avoidance position under the action of the tension spring, and the slurry recovery tank then moves away from directly below the lip.

[0081] The slurry recovery tank and the residue elimination mechanism are driven together by the same retraction action. This allows the rack to trigger the elimination operation and the recovery tank swing-in action simultaneously using the unidirectional movement of the rack. There is no need to set up a separate drive device for the slurry recovery tank, which further simplifies the system structure and reduces equipment costs. Moreover, the swing-in and swing-out of the recovery tank are automatically determined by the direction of the rack's movement.

[0082] In this embodiment, the time difference between the closing time of the coating valve and the starting time of the substrate retraction action is configured to be adjustable. The time difference is defined as the closing time of the coating valve minus the starting time of the substrate retraction. When the time difference is less than zero, the coating valve closes first, then the substrate retracts; when the time difference is greater than zero, the substrate retracts first, then the coating valve closes. The time difference is automatically adjusted by a phase adjustment mechanism based on the slurry viscosity.

[0083] The system also includes a phase adjustment mechanism, which comprises a viscosity signal acquisition module, a timing calculation module, and a phase execution module. The viscosity signal acquisition module includes an online viscometer and an analog-to-digital converter. The online viscometer is installed in the slurry supply pipeline, located upstream of the coating valve, and detects the slurry viscosity in real time, outputting an analog signal of 4mA to 20mA. The analog-to-digital converter converts the analog signal into a digital viscosity value and outputs it to the timing calculation module.

[0084] An online viscometer with a standard analog signal output of 4mA to 20mA is adopted, which is compatible with industrial control systems, facilitates signal transmission and anti-interference, and at the same time detects the viscosity of the slurry located upstream of the coating valve in real time, ensuring that the detected viscosity value reflects the state of the slurry to be coated, and improving the response speed and accuracy of phase adjustment.

[0085] The timing operation module and the phase execution module are integrated in the same programmable logic controller (PLC). The timing operation module is implemented through the operation instructions of the PLC, and the phase execution module is implemented in conjunction with the solid-state relay through the timer output function of the PLC.

[0086] The timing calculation module receives the digital viscosity value through the computational function of the programmable logic controller (PLC), calculates the time difference setting value according to a preset tuning algorithm, and outputs a time difference command to the phase execution module. The phase execution module includes a PLC and a solid-state relay. The PLC receives the time difference command, calculates the power-off trigger time of the solid-state relay using its internal timer, and outputs a control signal to the control terminal of the solid-state relay, thereby adjusting the power-off time of the electromagnetic shut-off valve coil. The timer base accuracy of the PLC is 1ms, and the time setting resolution is 1ms. The switching response time of the solid-state relay is no greater than 10ms, much smaller than the mechanical response time of the electromagnetic shut-off valve. Therefore, the time control accuracy of the phase execution module is determined by the timer accuracy of the PLC, meeting the control accuracy requirement of a time difference tuning range of -100ms to +50ms.

[0087] By using PLC timer instructions in conjunction with solid-state relays, the de-energization time of the electromagnetic shut-off valve coil can be precisely controlled, enabling precise adjustment of the closing time. The time control accuracy reaches ±1ms, meeting the precision requirements of timing coordination for slurries of different viscosities.

[0088] The tuning algorithm for the timing operation module is as follows: When the slurry viscosity η is greater than or equal to 5000 mPa·s, the time difference Δt is calculated according to the following formula: Δt = -k1 × (η - 5000); The value of k1 ranges from 0.02 to 0.04 ms / (mPa·s). In this embodiment, k1 = 0.02.

[0089] The determination of the above-mentioned range of k1 values ​​is based on the direct proportionality between the residual pressure release time of the slurry in the slit channel after the coating valve is closed and the viscosity. Through theoretical derivation and experimental verification, when k1 < 0.02, the residual pressure after the valve for high-viscosity slurry (η ≥ 8000 mPa·s) is not fully released before the retraction action begins, resulting in an additional residual amount at the lip exceeding 5 μm, which exceeds the coating accuracy requirements. When k1 > 0.04, the coating valve closes prematurely, and missing material streaks appear at the coating end. In this embodiment, k1 is set to 0.02. Experimental verification shows that when η = 8000 mPa·s, the coating end thickness deviation is controlled within ±1.5 μm, meeting the requirements of the lithium battery electrode coating process.

[0090] For example, when η = 8000 mPa·s, Δt = -0.02 × (8000 - 5000) = -60 ms, meaning the coating valve closes 60 ms early. When η = 10000 mPa·s, Δt = -0.02 × (10000 - 5000) = -100 ms, meaning the coating valve closes 100 ms early. The value of k1 is 0.02 instead of the upper limit of 0.04 to retain a certain control margin under extreme high-viscosity conditions, preventing the coating valve from closing too early and causing insufficient slurry supply at the coating end, resulting in edge defects.

[0091] In this embodiment, the proportionality coefficient k1 is calibrated under a typical structure with a coating die flow channel length L=50mm and a lip gap h=0.2mm. Those skilled in the art can adjust k1 accordingly based on the actual L and h values ​​of their own die, according to the relationship between residual pressure release time and L / h (this relationship is derived from the fluid resistance formula known in the art), through a limited number of conventional tests.

[0092] When the slurry viscosity η is less than or equal to 1000 mPa·s, the time difference Δt is calculated using the following formula: Δt = k2 × (1000 - η); The value of k2 ranges from 0.02 to 0.10 ms / (mPa·s). In this embodiment, k2 = 0.05.

[0093] The determination of the above-mentioned range of k2 values ​​is based on a fluid dynamics model of the retraction flow rate, retraction speed, and time difference of low-viscosity slurry during the retraction action. Experiments have verified that when k2 < 0.02, the suction effect generated by the retraction action is insufficient to completely retract the low-viscosity slurry from the lip gap, leaving a residue greater than 3 μm. When k2 > 0.10, the retraction action continues for too long, causing the edge of the coated area of ​​the substrate to be reverse-suctioned, resulting in serrated defects. In this embodiment, k2 is set to 0.05. Experiments have verified that at η = 500 mPa·s, the lip residue is reduced to below 1 μm, and the coating edge neatness meets the requirements for optical thin film coating.

[0094] In this embodiment, k2=0.05 was calibrated under the typical working condition of retraction speed vb=2mm / ms; those skilled in the art can adjust the value of k2 according to the actual retraction speed in an inverse proportional relationship.

[0095] For example, when η = 500 mPa·s, Δt = 0.05 × (1000 - 500) = 25 ms, meaning the substrate retracts for 25 ms before the coating valve closes. When η = 100 mPa·s, Δt = 0.05 × (1000 - 100) = 45 ms, meaning the substrate retracts for 45 ms before the coating valve closes.

[0096] When the slurry viscosity η is greater than 1000 mPa·s and less than 5000 mPa·s, the time difference Δt = 0. At this time, the coating valve closes and the substrate retraction is synchronized.

[0097] When the slurry viscosity is greater than or equal to 5000 mPa·s, the time difference is set to -20 ms to -100 ms, and the coating valve closes in advance to prevent high-viscosity slurry from continuing to flow out and forming additional residue during the valve closing delay. When the slurry viscosity is less than or equal to 1000 mPa·s, the time difference is set to 0 ms to +50 ms, and the substrate retracts first before the coating valve closes, thereby using the retraction action to draw low-viscosity slurry back from the lip gap and reduce the amount of residue.

[0098] Based on the typical parameters of this embodiment (lip gap h = 0.2 mm, retraction displacement δ = 0.02 mm ~ 0.1 mm), the volume increase generated by retraction is 0.8 mm³ ~ 4 mm³, corresponding to a negative pressure change of approximately 0.01 MPa ~ 0.05 MPa at the lip, which is sufficient to overcome the capillary backflow resistance (usually less than 0.005 MPa) of low-viscosity slurry (η ≤ 1000 mPa·s). Therefore, this suction effect is valid under the parameter conditions of this embodiment.

[0099] When the slurry viscosity η = 100 mPa·s, Δt = 0.05 × (1000 - 100) = 45 ms, which is close to the upper limit + 50 ms. Therefore, the upper limit of the time difference adjustment range + 50 ms covers the actual adjustment requirements of low-viscosity slurries. When the slurry viscosity η is greater than 1000 mPa·s and less than 5000 mPa·s, the time difference Δt = 0, and the coating valve closes synchronously with the substrate retraction.

[0100] The system automatically adjusts the time difference between the closing time of the coating valve and the starting time of the retraction based on the viscosity of the slurry, thereby adaptively selecting the optimal timing combination for slurries of different viscosities. This avoids additional residue under high viscosity conditions and reduces residue by utilizing the retraction suction effect under low viscosity conditions, significantly improving the system's adaptability to different slurry systems and breaking through the limitations of traditional fixed timing.

[0101] In this embodiment, a detection unit is also included to detect the thickness or distribution of residual slurry at the edge of the coating die lip. The detection unit is connected to an alarm unit. When the detected residual slurry thickness exceeds a preset threshold, the alarm unit issues an alarm signal, prompting the operator to replace the replaceable driven gear or adjust the retraction stroke length.

[0102] The preset threshold is defined as 20% of the target coating thickness T, and its absolute value is not less than 2μm, i.e., Tthreshold=max(0.2×T,2μm). For example, when the target coating thickness T=100μm, the threshold is 20μm; those skilled in the art can adjust this percentage within the range of 15% to 30% according to the thickness tolerance requirements of the specific coating process.

[0103] The detection unit includes multiple laser displacement sensors, which are uniformly arranged above the edge of the coating die lip along the width direction of the lip. The spacing between adjacent laser displacement sensors is 5mm to 15mm, covering the full width of the lip. Each laser displacement sensor independently detects the thickness of the residual slurry at its corresponding position, with a detection accuracy of 0.01mm to 0.1mm and a detection frequency of 1kHz to 10kHz.

[0104] Multiple laser displacement sensors are evenly arranged along the width of the lip to cover the entire width of the lip for residual distribution detection, with a detection accuracy of 0.01mm to 0.1mm. This allows for the identification of local thickness differences in residual material, providing accurate detection signals for the alarm unit.

[0105] The alarm unit is an audible and visual alarm or a human-machine interface display device. When the thickness of residual slurry at any detection location exceeds a preset threshold, the alarm unit emits an audible and visual alarm signal, or displays alarm information and abnormal location on the human-machine interface, prompting the operator to perform inspection and maintenance.

[0106] A monitoring strategy combining detection and alarm units is adopted to promptly detect abnormalities such as incomplete residue removal, prompting operators to intervene manually and avoid coating quality degradation due to residue accumulation. At the same time, the removal effect can be monitored at a relatively low hardware cost.

[0107] The alarm signal issued by the alarm unit includes an anomaly type judgment prompt, and the judgment rules are as follows: When the detection unit detects that the thickness of the residual slurry is unevenly distributed along the width direction, and the thickness in the middle area is greater than that in the edge area, it determines that the elimination stroke is insufficient, and the alarm unit prompts the operator to replace the replaceable driven gear with a larger number of teeth to increase the elimination stroke. When the detection unit detects that the thickness of the residual slurry is uniformly distributed in the width direction but all exceed the preset threshold, if the residue elimination mechanism is configured as a scraper, it is determined that the retraction stroke is insufficient, resulting in insufficient output torque of the one-way clutch or insufficient adhesion pressure of the scraper. The alarm unit prompts the operator to increase the retraction stroke length to 3mm~5mm or check whether the preload of the torsion spring in the scraper bracket has decreased. If the residue elimination mechanism is configured as a suction port, it is determined that the vacuum pump vacuum degree is insufficient or the suction port installation angle is offset. The alarm unit prompts the operator to check whether the vacuum pump vacuum degree has reached -0.05MPa or adjust the suction port installation angle to 45 degrees. When the detection unit detects an abnormal increase in the residual thickness in a local area, if the residue removal mechanism is configured as a scraper, it is determined that the scraper is partially worn, and the alarm unit prompts the operator to replace the scraper; if the residue removal mechanism is configured as a suction port, it is determined that the suction port is partially blocked, and the alarm unit prompts the operator to clean the suction port.

[0108] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. An automated intermittent precision coating system, characterized in that, include: A coating die head, used to apply a slurry to the surface of a substrate; A substrate conveying mechanism is used to drive the substrate to move intermittently. The substrate conveying mechanism includes a drive roller. During each intermittent pause, the substrate conveying mechanism drives the substrate to perform a retraction action. The direction of the retraction action is opposite to the coating travel direction to eliminate transmission backlash. The stroke length of the retraction action is 0.2 mm to 10 mm. Coating valve, used to control the slurry supply; And a residue removal mechanism, wherein the residue removal mechanism is mechanically coupled to the drive roller of the substrate conveying mechanism through a one-way transmission assembly, the one-way transmission assembly including a one-way clutch fixed to the shaft end of the drive roller and a gear and rack mechanism connected to the output end of the one-way clutch; The residue removal mechanism includes a scraper or a suction port; When the substrate performs a retraction action, the drive roller rotates in the reverse direction, the one-way clutch engages and transmits torque to the residue removal mechanism via the gear and rack mechanism, driving the residue removal mechanism to perform a removal operation on the lip edge of the coating die head; when the drive roller rotates in the forward direction, the one-way clutch idles, and the residue removal mechanism is disconnected from the drive roller. The unidirectional transmission assembly has a total transmission ratio, and the ratio of the elimination stroke of the residue elimination mechanism to the retraction stroke of the substrate is determined by this total transmission ratio, which is 5 to 40.

2. The intermittent precision coating automated operation system according to claim 1, characterized in that, The residue removal mechanism includes a scraper, and the removal operation includes: driving the scraper to move along the edge of the lip to scrape the residual paste away from the edge of the lip.

3. The intermittent precision coating automated operation system according to claim 1, characterized in that, The residue removal mechanism includes a suction port, and the removal operation includes: driving the suction port to move along the edge of the lip to suck the residual slurry into the recovery container.

4. The intermittent precision coating automated operation system according to claim 1, characterized in that, The one-way transmission assembly includes a one-way clutch, which is mounted on the shaft end of the drive roller. The one-way clutch engages and outputs torque only when the drive roller performs a retracting action, and idles during forward rotation. The output torque is transmitted to the residue elimination mechanism via a transmission component.

5. The intermittent precision coating automated operation system according to claim 1, characterized in that, The direction of movement of the residue removal mechanism is perpendicular to the direction of substrate retraction; The unidirectional transmission assembly includes a gear and rack mechanism, which converts the rotational motion of the drive roller into the linear reciprocating motion of the scraper or the suction port, wherein the direction of the linear reciprocating motion is along the width direction of the lip edge.

6. The intermittent precision coating automated operation system according to claim 5, characterized in that, It also includes a stroke adjustment mechanism, which includes a replaceable driven gear. By replacing the driven gear with one that has a different number of teeth, the transmission ratio of the gear and rack mechanism is changed, thereby changing the elimination stroke length so that the moving distance of the scraper or suction port matches the lip edge width.

7. The intermittent precision coating automated operation system according to claim 1, characterized in that, It also includes a slurry recovery tank, which is located below the lip of the coating die head; The recycling tank is linked to the residue elimination mechanism. When the residue elimination mechanism performs the elimination operation, the recycling tank is driven by the same retraction action to swing directly below the lip to receive the scraped or sucked residual slurry.

8. The intermittent precision coating automated operation system according to claim 1, characterized in that, The time difference between the closing time of the coating valve and the starting time of the substrate retraction action is configured to be adjustable; The time difference is defined as the time when the coating valve closes minus the time when the substrate retraction begins. When the time difference is less than zero, the coating valve closes first and then the substrate retracts; When the time difference is greater than zero, the substrate retracts first and then the coating valve closes. The system also includes a phase adjustment mechanism, which comprises a viscosity signal acquisition module, a timing calculation module, and a phase execution module connected in sequence. The viscosity signal acquisition module is used to detect the viscosity of the slurry in real time and output the viscosity signal. The timing calculation module receives the viscosity signal, calculates the time difference setting value according to the preset viscosity-time mapping relationship, and outputs the time difference command. The phase execution module receives the time difference command and adjusts the closing time of the coating valve; The time difference is automatically adjusted by the phase adjustment mechanism based on the slurry viscosity.

9. The intermittent precision coating automated operation system according to claim 6, characterized in that, It also includes a detection unit for detecting the thickness or distribution of residual slurry at the edge of the coating die lip; The detection unit is connected to an alarm unit. When the thickness of the detected residual slurry exceeds a preset threshold, the alarm unit issues an alarm signal to prompt the operator to replace the replaceable driven gear or adjust the retraction stroke length.

10. The intermittent precision coating automated operation system according to claim 7, characterized in that, The recycling tank is mounted below the coating die head via a swing arm. The swing arm is connected to a tension spring, and the preload of the tension spring keeps the recycling tank in an abduction position. The rack of the residue removal mechanism is provided with a fork at its end. The fork is an L-shaped plate with its horizontal arm extending toward the slurry recovery tank. The swing arm is provided with a long strip groove, the length of which extends along the moving direction of the rack, and the length of the groove is not less than 80% of the rack's travel. As the rack moves toward the end, the horizontal arm of the fork enters the slot and pushes the side wall of the slot, causing the recovery slot to swing directly below the lip at the beginning of the elimination operation and remain in the receiving position throughout the entire process of the fork sliding within the slot; when the rack returns to the starting end, the fork separates from the slot, and the recovery slot returns to the avoidance position under the action of the tension spring.

Images