A coating machine for eliminating coating bubbles and a method for using the coating machine

Abstract

The present application relates to the technical field of coating machine, particularly relates to a coating machine for eliminating coating bubbles and a use method of the coating machine, a turn roller for turning a base material is sequentially arranged above a material tray from top to bottom, a coating roller for coating paint on the surface of the base material, a metering roller for uniformly transferring the paint to the surface of the coating roller and a material taking roller for taking the paint from the material tray and transferring to the surface of the metering roller, the bottom of the material taking roller is soaked in the paint inside the material tray, a paint bucket is connected with the material tray through a reflux pipe, one end of a pneumatic diaphragm pump is connected with the paint bucket, the other end of the pneumatic diaphragm pump is connected with a liquid supplement pipe, the end of the liquid supplement pipe is inserted into the paint inside the material tray, a liquid level meter is arranged in the material tray, and a stirring device is arranged in the material tray. When the present application is used, air is avoided from entering the paint in the material tray, and the coating layer coated on the base material will not form shrinkage holes.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of coating machines, in particular to a coating machine for eliminating coating bubbles and a use method of the coating machine. BACKGROUND

[0002] Coating is one of the most critical links in the process of color coating, and its quality determines the performance and appearance effect reflected by the product. In the existing color coating industry, there are various coating methods, such as three-roll forward coating, three-roll reverse coating, four-roll forward coating, and four-roll reverse coating. Different feeding methods and roller performance requirements will also result in different coating effects. The rollers used in the coating process are generally chrome-plated iron rods or rubber rollers, or equipped with a scraper method. The selection of the process is also related to the selected coating. Currently, the coating used in the color coating industry is mainly based on lipids.

[0003] With the increasing demand for high-end products by existing customers, the requirements for coating construction are also very high. Household appliance pre-coated products have very high appearance requirements. There are still some problems in the pre-coated products of the household appliance series, especially small shrinkage holes, which not only affect the appearance, but also pose a potential risk to the performance of the product.

[0004] Shrinkage holes are caused by air bubbles in the coating process. The material in the tray is in a state of long-term stirring and material falling. During the process, air bubbles are generated due to contact with air. If the air bubbles successfully pass through the metering roller, they will be transferred to the coating roller. Air bubbles in the coating form small bubbles. Coating with small bubbles is applied to the substrate, forming shrinkage holes. These shrinkage holes are very small in appearance and can only be found under a magnifying glass. However, these shrinkage holes will cause the following problems: large particle size of shrinkage holes will directly affect the appearance of the product, which belongs to unqualified products; shrinkage holes are holes that penetrate the coating, which means that the coating does not have the function of protection; the substrate is directly in contact with the external environment, which poses a huge quality risk of rusting.

[0005] Therefore, it is necessary to design a coating mechanism that avoids shrinkage holes. SUMMARY

[0006] The present application aims to overcome the defects and shortcomings of the prior art and provide a coating machine for eliminating coating bubbles and a use method of the coating machine.

[0007] To achieve the above-mentioned purpose, the technical solution adopted by the present application is as follows:

[0008] The present invention discloses a coating machine for eliminating coating bubbles, comprising a material tray containing paint, a paint bucket, and a pneumatic diaphragm pump; above the material tray, from top to bottom, are arranged a steering roller for turning the substrate, a coating roller for applying paint to the surface of the substrate, a metering roller for uniformly transferring paint to the surface of the coating roller, and a pick-up roller for taking paint from the material tray and transferring it to the surface of the metering roller; the bottom of the pick-up roller is immersed in the paint inside the material tray; the rotation direction of the metering roller is opposite to the rotation direction of the pick-up roller; the rotation direction of the coating roller is opposite to the rotation direction of the metering roller; the rotation direction of the steering roller is opposite to the rotation direction of the coating roller; a feeding balance device is provided between the material tray and the paint bucket to ensure that the paint level inside the material tray remains constant; and a stirring device is provided inside the material tray.

[0009] Furthermore, the material-taking roller is a roller with a smooth surface.

[0010] Furthermore, the depth to which the material-taking roller is immersed in the material tray is the immersion depth; the immersion depth is three-tenths of the diameter of the material-taking roller.

[0011] Furthermore, the stirring device consists of a roller and stirring needles evenly distributed on the surface of the roller.

[0012] How to use the coating mechanism

[0013] a. Pre-adjust the gap between the coating roller and the metering roller so that the gap is equal to the thickness of the coating on the substrate surface;

[0014] b. Adjust the depth of the material taking roller immersed in the coating in the material tray so that the immersion depth is three-tenths of the diameter of the material taking roller;

[0015] c. Set the reference depth of the level gauge so that when the immersion depth is greater than three-tenths of the diameter of the feeding roller, the flow rate of the pneumatic diaphragm pump decreases, and when the immersion depth is less than three-tenths of the diameter of the feeding roller, the flow rate of the pneumatic diaphragm pump increases.

[0016] d. The rotation direction of the feeding roller is opposite to that of the metering roller, the rotation direction of the coating roller is opposite to that of the metering roller, the rotation direction of the steering roller is opposite to that of the coating roller, and the rotation direction of the feeding roller is the same as that of the roller in the mixing device.

[0017] e. The unwound substrate passes through the gap between the coating roller and the guide roller, and after passing around the guide roller, it is connected to the winding device; the linear speeds of the guide roller, coating roller, metering roller, roller of the stirring device, and take-up roller are all equal.

[0018] With the above structure, the beneficial effects of this invention are as follows: The coating machine for eliminating coating bubbles described in this invention uses a feeding balance device to ensure a constant coating liquid level inside the material tray; the take-up roller is immersed in the coating inside the material tray and stirred evenly by a stirring device; when the take-up roller rotates, a layer of coating is evenly coated on its surface, and then the coating is transferred to the metering roller at the intersection of the take-up roller and the metering roller; excess coating on the take-up roller smoothly returns to the material tray; the coating on the metering roller is transferred to the coating roller at the intersection with the coating roller, and finally coated onto the substrate surface on the guide roller via the coating roller; A pneumatic diaphragm pump with a replenishment pipe extends into the paint tray, preventing air from being introduced into the paint inside. A level gauge detects the liquid level inside the tray, ensuring the paint remains immersed at a constant height on the take-up roller. The metering roller rotates in the opposite direction to the take-up roller, the coating roller in the opposite direction, and the steering roller in the opposite direction. This reverse rotation creates a squeezing force on the contact surfaces of the two rollers, further eliminating air bubbles through physical force. The paint can smoothly flow back into the tray, preventing air from entering and thus preventing pinholes in the coating applied to the substrate. Attached Figure Description

[0019] Fig. 1 This is a schematic diagram of the structure of the present invention;

[0020] Fig. 2 This is a structural diagram of the coating material immersed in the material tray by the feeding roller;

[0021] Explanation of reference numerals in the attached figures:

[0022] 1. Directional roller; 2. Coating roller; 3. Metering roller; 4. Pick-up roller; 5. Material tray;

[0023] 6. Agitator; 601. Agitator needle; 7. Level gauge; 8. Paint bucket; 9. Pneumatic diaphragm pump;

[0024] 10. Liquid replenishment tube; 11. Return tube A. Substrate; B. Immersion depth. Detailed Implementation

[0025] The invention will now be further described with reference to the accompanying drawings.

[0026] like Figs. 1-2As shown, the coating machine for eliminating coating bubbles according to the present invention includes a material tray 5 containing paint, a paint bucket 8, and a pneumatic diaphragm pump 9. Above the material tray 5, from top to bottom, are arranged a steering roller 1 for turning the substrate A, a coating roller 2 for applying paint to the surface of the substrate A, a metering roller 3 for uniformly transferring paint to the surface of the coating roller 2, and a take-up roller 4 for taking paint from the material tray 5 and transferring it to the surface of the metering roller 3. The bottom of the take-up roller 4 is immersed in the paint inside the material tray 5. The rotation direction of the metering roller 3 is opposite to the rotation direction of the take-up roller 4. The rotation direction of the coating roller 2 is opposite to the rotation direction of the metering roller 3. The rotation direction of the steering roller 1 is opposite to the rotation direction of the coating roller 2. The opposite rotation direction causes the contact surface of the two rollers to form a squeezing force, which can further eliminate bubbles through physical force.

[0027] A feeding balance device is provided between the material tray 5 and the paint bucket 8 to ensure that the paint liquid level inside the material tray 5 remains constant; a stirring device 6 is provided inside the material tray 5; the feeding balance device consists of a level gauge 7, a return pipe 11, a pneumatic diaphragm pump 9, and a replenishment pipe 10; the paint bucket 8 is connected to the material tray 5 through the return pipe 11; one end of the pneumatic diaphragm pump 9 is connected to the paint bucket (8); the other end of the pneumatic diaphragm pump 9 is connected to the replenishment pipe 10. Phase 0 is connected; the end of the replenishing pipe 10 extends into the paint inside the material tray 5; a level gauge 7 is installed inside the material tray 5; the metering roller 3 is a single roller; the paint in the material tray 5 enters the paint tank 8 through the return pipe 11, and then the paint in the paint tank 8 is fed into the material tray 5 through the pneumatic diaphragm pump 9 and the replenishing pipe 10. The inlet speed of the replenishing pipe 10 is greater than the return speed of the return pipe 11, so that the liquid level in the material tray 5 remains unchanged after being removed by the picking roller 4.

[0028] The flow rate of the replenishment pipe 10 is equal to the sum of the feed flow rate of the metering roller 3 and the flow rate of the return pipe 11.

[0029] The pick-up roller 4 is immersed in the coating material inside the material tray 5 and stirred evenly by the stirring device 6. When the pick-up roller 4 rotates, a layer of coating material is evenly coated on its surface. Then, at the intersection of the pick-up roller 4 and the metering roller 3, the coating material is transferred to the metering roller 3. Excess coating material on the pick-up roller 4 is smoothly returned to the material tray 5. The coating material on the metering roller 3 is transferred to the coating roller 2 at the intersection with the coating roller 2. Finally, the coating material is coated onto the surface of the substrate A on the guide roller 1 by the coating roller 2. A pneumatic diaphragm pump 9 with a replenishment pipe 10 is used to penetrate into the coating material, preventing air from being carried in. The level gauge 7 is used to detect the level of the coating inside the tray 5. The coating in the tray 5 is immersed at a constant height of the take-up roller 4. The rotation direction of the metering roller is opposite to that of the take-up roller. The rotation direction of the coating roller is opposite to that of the metering roller. The rotation direction of the steering roller is opposite to that of the coating roller. The opposite direction causes the contact surface of the two rollers to form a squeezing force, which can further eliminate air bubbles through physical force. The coating can flow smoothly back to the tray, preventing air from entering the coating in the tray, so that the coating on the substrate will not form pinholes.

[0030] In a preferred embodiment of the present invention, the feeding roller 4 is a roller with a smooth surface; the surface of the feeding roller 4 achieves a relatively smooth effect to eliminate the unevenness of the surface of the feeding roller 4 and prevent air from being introduced into the coating of the metering roller 3 or the coating of the material tray 5 by the feeding roller 4, so that the coating of the substrate A will not form shrinkage cavities.

[0031] In a preferred embodiment of the present invention, the immersion depth of the feeding roller 4 in the material tray 5 is B; the immersion depth B is three-tenths of the diameter of the feeding roller 4; according to the data obtained by immersing the roller into the coating, when the roller is immersed to 30%, the amount of coating extracted is reasonable, and at the same time, the air bubbles entering the coating from the roller cutting surface are smaller, reducing the chance of air bubbles entering the coating during material extraction. When the roller is immersed in the coating to 30%, the dynamic impact on the coating can be minimized, and the material extraction requirements can also be met.

[0032] In a preferred embodiment of the present invention, the stirring device 6 comprises a roller and stirring needles 601 evenly distributed on the surface of the roller; a motor is connected to the roller to drive its rotation, and the stirring needles 601 stir the mixture when the motor is started. This comb-shaped roller structure allows for uniform mixing of the coating, and air contained in the coating is released onto the coating surface after being stirred by the stirring needles 601, thus minimizing the formation of air bubbles in the coating. The material-taking roller 4 is arranged parallel to the roller of the stirring device 6. The rotation direction of the rollers in the mixing device 6 is the same as that of the rollers in the mixing device 6; the linear velocity of the pick-up roller 4 is equal to that of the rollers in the mixing device 6; the pick-up roller 4 and the mixing device 6 create disturbances in the same direction for the coating in the tray 5, thus preventing the direction of the pick-up roller 4 pushing the coating in the tray 5 during pick-up from the direction of the mixing device 6 pushing the coating in the tray 5 during mixing. In addition, the pick-up roller 4 and the rollers in the mixing device 6 use the same linear velocity, so that the two liquid flows generated by them have the same velocity, thus preventing convection and allowing external gas to enter the coating in the tray 5.

[0033] How to use the coating machine

[0034] a. Pre-adjust the gap between the coating roller 2 and the metering roller 3 so that the gap is equal to the thickness of the coating on the surface of the substrate A;

[0035] b. Adjust the depth of the material taking roller 4 immersed in the coating material in the material tray 5 so that the immersion depth B is three-tenths of the diameter of the material taking roller 4.

[0036] c. Set the reference depth of the level gauge 7 so that when the immersion depth B is greater than three-tenths of the diameter of the feeding roller 4, the flow rate of the pneumatic diaphragm pump 9 decreases, and when the immersion depth B is less than three-tenths of the diameter of the feeding roller 4, the flow rate of the pneumatic diaphragm pump 9 increases.

[0037] d. The rotation direction of the take-up roller 4 is opposite to that of the metering roller 3, and the rotation direction of the coating roller 2 is opposite to that of the metering roller 3; the rotation direction of the guide roller 1 is opposite to that of the coating roller 2; the rotation direction of the take-up roller 4 is the same as that of the roller in the mixing device 6; e. The unwound substrate A passes through the gap between the coating roller 2 and the guide roller 1, and after passing around the guide roller 1, it is connected to the winding device; the linear velocities of the guide roller 1, coating roller 2, metering roller 3, the roller of the mixing device 6, and the take-up roller 4 are all equal.

[0038] The beneficial effects of using this invention are as follows:

[0039] 1. When the immersion depth B is 30% of the diameter of the feeding roller 4, the amount of paint extracted is reasonable. At the same time, the air bubbles entering the paint from the roller cutting surface are smaller, reducing the chance of air bubbles entering the paint during material extraction. 30% of the roller entering the paint can minimize the dynamic impact on the paint and also meet the material extraction requirements.

[0040] 2. The rotation direction of the metering roller is opposite to that of the feeding roller; the rotation direction of the coating roller is also opposite to that of the metering roller. This opposite direction causes the contact surface of the two rollers to form a squeezing force, which can further eliminate air bubbles through physical force and reduce the air bubbles generated during coating.

[0041] 3. The rotation direction of the feeding roller and the roller in the mixing device is the same; the linear velocity of the feeding roller is equal to the linear velocity of the roller in the mixing device; by the feeding roller and the mixing device creating disturbances in the same direction for the coating in the tray, convection is avoided between the direction in which the feeding roller pushes the coating in the tray during feeding and the direction in which the mixing device pushes the coating in the tray during mixing. In addition, the feeding roller and the roller in the mixing device use the same linear velocity, so that the two liquid flows generated by them have the same velocity, further reducing the convection generated during feeding and mixing, and reducing the chance of air entering the tray.

[0042] The above description is only a preferred embodiment of the present invention. Therefore, all equivalent changes or modifications made to the structure, features and principles described in the claims of this patent application are included in the scope of this patent application.

Claims

1. A coating machine for eliminating coating bubbles, characterized in that: It includes a tray (5) containing paint and a paint bucket (8); above the tray (5), from top to bottom, are arranged a steering roller (1) for turning the substrate (A), a coating roller (2) for applying paint to the surface of the substrate (A), a metering roller (3) for uniformly transferring paint to the surface of the coating roller (2), and a pick-up roller (4) for taking paint out of the tray (5) and transferring it to the surface of the metering roller (3); the bottom of the pick-up roller (4) is immersed in the paint inside the tray (5); the rotation direction of the metering roller (3) is opposite to the rotation direction of the pick-up roller (4); the rotation direction of the coating roller (2) is opposite to that of the metering roller (3); the rotation direction of the steering roller (1) is opposite to that of the coating roller (2); A feeding balance device is provided between the material tray (5) and the paint bucket (8) to ensure that the paint liquid level inside the material tray (5) remains constant; a stirring device (6) is provided inside the material tray (5). The stirring device (6) consists of a roller and stirring needles (601) evenly distributed on the surface of the roller; the material taking roller (4) is arranged parallel to the roller of the stirring device (6); the linear velocity of the material taking roller (4) is equal to the linear velocity of the roller in the stirring device (6).

2. The coating machine for eliminating coating bubbles according to claim 1, characterized in that: The depth to which the material taking roller (4) is immersed in the material tray (5) is called the immersion depth (B); the immersion depth (B) is three-tenths of the diameter of the material taking roller (4).

3. A method for using a coating machine to eliminate coating bubbles, characterized in that, Using the coating machine as described in any one of claims 1-2 includes the following steps: a. Pre-adjust the gap between the coating roller (2) and the metering roller (3) so that the gap is equal to the thickness of the coating on the surface of the substrate (A); b. Adjust the depth of the material taking roller (4) immersed in the coating in the material tray (5) so that the immersion depth (B) is three-tenths of the diameter of the material taking roller (4); c. Set the reference depth of the level gauge (7) so that when the immersion depth (B) is greater than three-tenths of the diameter of the feeding roller (4), the flow rate of the pneumatic diaphragm pump (9) decreases, and when the immersion depth (B) is less than three-tenths of the diameter of the feeding roller (4), the flow rate of the pneumatic diaphragm pump (9) increases. d. The rotation direction of the take-up roller (4) is opposite to that of the metering roller (3), and the rotation direction of the coating roller (2) is opposite to that of the metering roller (3); the rotation direction of the steering roller (1) is opposite to that of the coating roller (2); the rotation direction of the take-up roller (4) is the same as that of the roller in the stirring device (6); e. The unwound substrate (A) passes through the gap between the coating roller (2) and the steering roller (1), and is connected to the winding device after passing around the steering roller (1); the linear speeds of the steering roller (1), the coating roller (2), the metering roller (3), the roller in the stirring device (6), and the take-up roller (4) are all equal.

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