JPH09285758A - Method for coating cut face of precoated steel sheet and device therefor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To form a high-quality local coating film having a specified uniform thickness with high efficiency at a low cost by wiping the surface of a coating pad with gas to remove an excessive coating material and then pressing the pad on the cut face of a precoated steel sheet with a controlled force. SOLUTION: A coating pad 1 is dipped in a coating tank and/or a coating material is sent under pressure from the inside of the pad 1 to impregnate the sponge or unwoven fabric and/or woven fabric as the material of the pad 1. The coating material depositing on the pad 1 surface is then wiped off by a treating gas passed through the gas knife of a gas knife header 5. Subsequently, the pad 1 impregnated with the coating material is pressed with a specified force on the cut face of a precoated steel sheet 10 with a masking film 8 stuck on the precoated decorative face to coat the sheet with the coating material. At this time, the pressing is performed by a cylinder 15.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to electric appliances, furniture,
The present invention relates to an improvement in a coating method of a cut surface of a building material, an automobile part, and the like, which has a structure in which a precoated steel plate is used as an outer plate and is finally cut to a product size.

[0002]

2. Description of the Related Art For durable consumer goods such as electric appliances, furniture, building materials and automobile parts, the outer shell structure using steel sheets has been reviewed from the viewpoint of recyclability, elimination of harmful substances in waste treatment, and ecology. Has been. Further, among the steel sheets used, a pre-coated steel sheet in which a steel manufacturer coats the outer surface of the steel sheet as a final product and uses it as a raw material to omit painting by the final product manufacturer is useful. The problem of using the precoated steel sheet as an outer plate is that when the material precoated steel sheet is processed and formed and then finally cut to the product size, the cut surface is a bare iron surface which is not coated or plated. For this reason, products used in environments that require rust prevention (even products that are used in normal indoor environments often require rust prevention for the parts that appear on the outside of the product image) and pre-coated steel sheets. If the discoloration of the coating color and the metallic luster of the cut surface deteriorates the product image, abandon the use of precoated steel sheets (usually use steel sheets and apply after processing) or post-paint the cut surfaces. There was a need.

In the post-coating of the cut surface, it is necessary to prevent the paint from protruding onto the decorative surface in order to maintain the beauty of the decorative surface of the precoated steel sheet. However, the thickness of the steel sheet used here is a very thin steel sheet of about 1 mm or less, and it is not possible to apply the coating on the cut surface of this thickness without protruding to the decorative surface. It is very difficult to use various manual coating methods such as roller coating, let alone automatic coating.

Conventionally, a technique called masking has been adopted for these problems. This is because by applying a tape along the painted surface in advance to the part where you want to prevent the paint from squeezing out, you can apply post-painting in this state and peel off the tape after the paint is finished, so that the post-painting does not squeeze out on the surface you want to protect. It is a beautiful painting. As described above, various masking methods can be applied. Also,
As a conventional technique relating to the application of a drug to the end face of a plate material, the technical field is different, but Japanese Patent Application Laid-Open No. H5-263271 discloses an invention in which a photoresist is applied to the end face of a lead frame plate.

[0005]

However, in the protective coating of the cut surface of the precoated steel sheet, which is the subject of the present invention, it is most preferable to apply the coating only to the cut surface and its vicinity in terms of coating cost and appearance. Since it is preferable, the above-mentioned conventional spray coating is not suitable for the protective coating of the cut surface of the precoated steel sheet even on the premise of masking.
Also, with simple roller coating, the steel plate cutting surface near the knife edge (generally cutting burrs also remain) is painted,
There is a problem that the roller is easily damaged. In addition to this, since the actual contact area becomes small due to the point of contact between the coating roller and the steel plate cut surface, a large change in the contact force of the coated area per unit area is unavoidable. It is difficult to perform stable and uniform coating in a thick coating having a film thickness of several tens of μm so as to cover the burr.

Further, the prior art of applying a chemical to the end face of a plate material disclosed in Japanese Patent Laid-Open No. 5-263271 is an invention of applying a photoresist to the end face of a lead frame plate, which is different only in the technical field. However, it is difficult to apply the present invention to the case where the robot is provided with a coating device as in the present invention and the coating is performed by its movement, or when the object is the end face of the opening. Therefore, the present invention has been made in order to advantageously solve the above-mentioned problems, and in coating a cut surface (edge portion) of a precoated steel sheet, having a thickness of several tens of μm, low cost, high efficiency, and high quality. An object of the present invention is to provide a method for coating a cut surface of a precoated steel sheet and a device therefor capable of locally coating a uniform film thickness.

[0007]

In order to solve the above problems, as a result of various studies by the present inventors, in order to apply a coating on a knife-edge-shaped coating surface in a required amount and only in a required portion, The stamping method is used to press the paint pad against the cut surface of the precoated steel sheet, and finally the amount of paint retained on the paint pad surface is controlled by gas wiping.In addition, the paint pad is applied to the cut surface of the precoated steel sheet to be painted. By controlling the pressing force at the time of pressing, the method and device that adjusts the amount of paint squeezed out from the coating pad and the device to stabilize and uniformize the amount applied to the cut surface of the precoated steel sheet. It was found to be optimal. That is, the gist of the present invention is to attach a masking film to at least the outer surface of the product (hereinafter referred to as the decorative surface) of a steel plate (hereinafter referred to as the pre-coated steel plate) on which the final product is coated in a flat plate state, and then cut the cut surface. In the method for coating the cut surface of the precoated steel sheet, the coating pad made of sponge or non-woven fabric and / or woven fabric is impregnated with the coating material, and the surface of the coating pad is wiped with gas to remove excess coating material. Therefore, the coating pad is pressed against the cut surface of the precoated steel sheet while controlling the force.

When pressing the coating pad against the cut surface of the precoated steel sheet while controlling the force, the setting value of the pressing force is set in two or more steps, and in the final coating step (the pressing step immediately before the coating pad separates from the cut surface of the precoated steel sheet). It is characterized by pressing and holding for a predetermined time with a set value of the pressing force smaller than the maximum pressing force.

When the coating pad is pressed against the cut surface of the precoated steel sheet while controlling the force, the inclination d = 1/1 with reference to the direction perpendicular to the cut surface of the precoated steel sheet.
It is characterized in that the coating pad is pressed and moved from the direction in which it is inclined from 0 to 1/3.

After the application of the coating material to the cut surface by the coating pad and before the drying or curing of the coating material, the coating material applied to the cut surface is reflowed using warm air to be flattened. Characterize.

In a coating apparatus for coating a cut surface of a precoated steel sheet having a masking film attached to at least the decorative surface of the precoated steel sheet, a coating pad made of sponge or non-woven fabric and / or woven cloth, and impregnation of the coating material with the coating pad. A mechanism for dipping and / or pumping / bleeding to the inner surface, a mechanism for wiping off excess coating paint on the surface of the coating pad with a gas (gas knife), and a coating pad on the cut surface of the precoated steel sheet. And a mechanism for pressing while controlling the force.

Further, the inside of the coating pad is made of a non-woven fabric, and at least the surface of the outer skin which comes into contact with the cut surface of the pre-coated steel sheet is covered with a woven fabric, and the non-woven fabric and the pedestal having a rigidity. It is characterized by the structure attached to.

The pressing mechanism of the coating pad against the cut surface of the pre-coated steel sheet is a pressing mechanism by a fluid pressure cylinder, and the circuit of the fluid pressure cylinder can control the pressing pressure of the coating pad during pressing coating by a multistage pressure setting. A feature is that a circuit is provided.

The pressing mechanism of the coating pad on the cut surface of the precoated steel sheet is a pressing mechanism by a mechanical spring mechanism connected in multiple stages in parallel and / or in series, and the mechanical spring mechanism has a spring output that is different from that of the coating pad. Depending on the mutual movement stroke with the holding device, it has a mechanism that changes in multiple steps by releasing or re-restraining the restraint as a spring force in sequence, thereby pressing the coating pad during pressing coating. The feature is that the pressure is variable.

The pressing mechanism for pressing the coating pad against the cut surface of the precoated steel plate may be configured by combining the pressing mechanism with the fluid pressure cylinder according to claim 7 and the pressing mechanism with the mechanical spring mechanism according to claim 8. Is characterized by.

[0016]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a processing flow chart showing the basic processing of the present invention. Further, FIG. 4 is a diagram showing an example of a device configuration for performing basic processing and its operation. The present invention is premised on attaching a masking film to at least the decorative surface of the precoated steel sheet and coating the cut surface. Generally, the only cosmetic surface that can be used as a product is the one that is the front (front) surface of the product (there is a lot of rust-proof treatment on the back surface). As will be described, a masking film may be selectively attached to one side or both sides of the precoated steel sheet, if necessary, and the masking film may be replaced with a tape.

The present invention basically consists of a three-step process. That is, the first is a process of impregnating the coating pad 1 with the coating material, the second is a wiping process of controlling an appropriate amount of the coating material on the surface of the coating pad 1, and the third is the coating pad 1 prepared as described above. Is pressed against the cut surface of the pre-coated steel sheet 10 to be coated so that the required amount of coating material is attached.

First, in the first process, the coating pad 1 is dipped in a predetermined depth of the coating tank and / or the coating material is pressure-fed from the inside of the coating pad 1 to make the coating pad 1
The sponge or the non-woven fabric and / or the woven fabric, which is the raw material, is sufficiently impregnated with the paint.

Next, in the second process, the coating gas adhering to the surface of the coating pad 1 is appropriately cut (wiping) by the processing gas passed through the gas knife portion of the gas knife header 5. In this process, it is difficult to homogenize and eliminate the extra paint on the surface only by controlling the supply amount of the paint corresponding to the first process, and there is plenty of paint on the surface of the paint pad 1 in the pressed state of the next process. If too much, too much paint adheres to the pre-coated steel sheet 10 to form a raindrop-like coated surface with many irregularities, which is aesthetically undesirable, and is therefore an essential process. Adopting gas wiping as a liquid draining means of the coating pad 1 after applying a large amount of paint, liquid draining by contact between the coating pad 1 and solid such as liquid draining with a roller or plate blade This is because it is difficult to achieve uniform drainage as a surface, and a large amount of excess paint extruded remains on the side surfaces other than the surface contacting the draining tool, which is not preferable.

In other words, it is important that the coating pad 1 be impregnated and held with an appropriate amount of paint uniformly by gas wiping, that is, in a state where the paint does not rise on the surface. The degree of wiping is controlled by the strength of the jet flow (supply pressure) and the passage time. Of course, the slower the wiping over a longer time, the smaller the amount of paint retained on the coating pad 1, and the lighter the coating.

Next, in the third process, the masking film 8 is applied to the pre-coated decorative surface of the coating pad 1 impregnated with the appropriate amount of paint in the above process.
Is applied to the cut surface (surface to be coated) of the pre-coated steel sheet 10 to which is adhered with a predetermined pressing pressure to apply the impregnated paint. In this way, by coating the sponge or non-woven fabric and / or woven fabric as a base material with the coating material and pressing it against the cut surface of the pre-coated steel sheet that is the object, the coating material impregnated into the coating pad is squeezed out. The amount of paint squeezed out changes according to the pressing force of the coating pad, and the application amount can be controlled by controlling the maximum pressing force.

In the inventions of claim 2 and claim 7 to claim 9, when the coating pad 1 is pressed against the cut surface of the precoated steel sheet 10 while controlling the force, the set value of the pressing force is set in two or more steps. Depending on the viscosity and properties of the paint, if a large amount of paint partially adheres to the surface of the paint, and the unevenness of the raindrop-like paint is conspicuous on the painted surface, the coating pad 1 is a Before leaving the cut surface, keep contact with a small pressing pressure for a certain period of time, and suck the excess raindrop-like paint squeezed out at the maximum pressing force again to the coating pad 1 to achieve uniform paint adhesion. This is a preferable mode in which the irregularities on the surface can be reduced.

FIG. 5 shows an example of a pneumatic circuit for performing this multi-step pressing operation. In this example, the first-stage pressure setting valve 11 and the second-stage pressure setting valve 12 are provided, and these are switched to press the coating pad 1 by the cylinder 15 which is operated by air pressure. A typical example of the pressing force pattern generated by this is shown in FIG. After the coating pad 1 is pressed by the pressing force P1 generated by the first-stage pressure setting valve 11, the second-stage pressure setting valve 12 is turned on before the coating pad 1 separates from the cut surface of the precoated steel plate 10, and the pressing force P2
Then, the coating material is pressed and held for a certain time (about 1 second for a normal coating material), and the coating material extraly attached to the cut surface of the precoated steel sheet 10 is sucked up by the coating pad 1. As the fluid pressure, it is most preferable to use air pressure in terms of easiness of handling and cost, but even if fluid pressure such as hydraulic pressure is used, the effect of coating does not change.

FIG. 7 is a diagram for explaining a mechanical spring mechanism which is another means for performing the multi-step pressing operation. This mechanism is configured such that two different springs are combined to perform two-step pressing, and the first-step spring 21 and the second-step spring 22 are arranged in series so that the coating pad 1 and the robot hand 20 are relatively opposed to each other. The mechanism is such that these two springs are made effective / ineffective at the position to generate a two-step pressing force change. That is, if the pressing operation of the robot hand 20 is further advanced after the coating pad 1 comes into contact with the pre-coated steel plate 10, the distance between the coating pad 1 and the robot hand 20 is shortened, but at this time, the second step, which is a weak spring, is performed. The spring 22 contracts first. Going further, the second stage spring 2
When 2 comes into close contact (or hits the setting stopper),
The first-stage spring 21, which is a strong spring, starts to work, and the maximum pressing force is generated according to this compression amount.

After the predetermined maximum pressing force is reached, when the backward movement is started (when the robot hand 20 is started to be pulled), the pressing force gradually weakens and the extension of the first step spring 21 is set to the predetermined length by the guide. Restrained (first stage spring 21
Initial state). In addition, by advancing the backward movement, the second
Since the step spring 22 starts to work and the coating pad 1 is pressed by this elastic force, the extension of the second step spring 22 is restrained by a guide set to a predetermined length (until the initial state of the second step spring 22). Pre-coated steel plate 1 for coating pad 1 for a certain period of time
A slight pressure is applied to 0, and then the surface is separated from the painted surface. As described above, as the multi-step pressing mechanism, a fluid pressure mechanism, a mechanical spring mechanism, or both of them can be used together.

According to the third aspect of the present invention, the inclination d = 1 / 100-based on the direction perpendicular to the cut surface of the precoated steel sheet.
The coating pad 1 is pressed from the 1/3 inclined direction (for example, the direction in which the cutting burr 9 is exposed as shown in FIG. 2),
If the coating pad 1 is slightly ironed on the cutting burr side and a large amount of paint is intentionally applied (thick coating) on the cutting burr side, the coating burr 9 can be covered with an efficient coating method. It is possible and preferable. However, when the cut surface of the target precoated steel sheet 10 is not a straight line,
As shown in FIG. 2, it is important to set the cut surface of the precoated steel plate 10 and the paint surface of the coating pad 1 to be parallel to each other. Here, the lower limit value 1/100 of the slope d is
Since the amount of penetrating of the coating pad 1 is about 1 mm, in order to give the minimum amount of burr height (about 10 μm) for ironing, 1 /
It is determined because a slope of 100 or more is required.
Further, the upper limit value ⅓ of the slope d is sufficient if the maximum height of the cutting burr is expected to be 300 μm, and the pressing force of the coating pad 1 causes the pre-coated steel sheet 10 to be coated to The upper limit of 1/3 is set because it receives the force to turn out of the plane.

As described above, when the oblique pressing is performed, thick coating is applied to the corner of the surface of the precoated steel sheet on the inclined entry side, and
It is possible to apply a thin coating to the corner of the steel plate surface on the opposite side. As opposed to using the effect of thick coating (coating of cutting burr with paint) as described above, it is also possible to use thin coating. For example, in order to apply a paint having a high viscosity (several hundreds of poises or more) according to the present invention without unevenness, it is effective to use a thin coating. That is, this can be achieved by pressing and painting the side of the surface of the precoated steel sheet on which the paint is to be left (the side opposite to the masked surface) as the outgoing side surface of the oblique pressing.

According to the fourth aspect of the present invention, after the basic process of the above three steps, when the viscosity is high and the raindrop-like irregularities due to the paint on the coated surface remain, as shown in FIG. Before curing, the temperature of the adhered paint part is raised by spraying hot air etc. to temporarily reduce the viscosity, and the paint retained on the convex part is reflowed by surface tension and gravity,
It is preferable because the coated surface can be flattened. In particular, when an ultraviolet curable coating material is used, the coating material is not solidified by warm air, so that the effect of flattening the coated surface is great. Also,
If possible, it is more preferable to perform hot air reflow in a vertical posture in which the coating convex portion generated on the coating surface is positioned on the upper side so that the gravity effect is also taken into consideration and a higher effect is obtained.

The development of the above-described three basic steps of the present invention into actual steps includes a station for impregnating the paint on the coating pad 1, a station for cutting the surface of the coating pad 1 with a gas knife, and a precoating process. By providing a minimum of three stations for pressing the coating pad 1 against the cut surface of the steel plate, allowing the robot to hold the coating pad 1, and performing a predetermined process to move between these stations. It is possible to develop the simplest actual process. Of course, depending on the production amount, it is also possible to make a dedicated processing device and carry out these processes in a line work. When the paint applied last is dried and cured, it is completed as an outer panel component, so it is assembled with other component parts of the product to complete the product.

The coating pad 1 may have a structure in which a sponge, a non-woven fabric, or a woven fabric is simply attached to a rigid pedestal in order to impregnate the coating material and hold it. However, when it is necessary to perform thick coating, a sponge or a soft non-woven fabric is used as the inner surface base material in order to impregnate and apply many paints. It is desirable to construct the coating pad 1 by covering the sponge or the non-woven fabric with a woven fabric so that the distance is on the order of micrometers. FIG. 8 is a structural example of a coating pad in which the surface of the nonwoven fabric 1-2 as the inner surface base material is covered with the woven fabric 1-1. When the coating pad 1 which does not use the woven cloth of the outer skin is brought into contact with the surface to be coated, fluff is raised on the contact surface in the case of the non-woven fabric, and when the coating pad 1 is pressed and released, a small protrusion-shaped coating adheres, It is not preferable because bubbles may be mixed on the coated surface. Even in the case of a sponge coating pad that does not use a woven cloth for the outer skin, the contact surface does not have fluffing, but the spacing of the dense and dense paint on the surface is large, and the same problem is feared.

The sponge or non-woven fabric and / or woven fabric as the base material of the coating pad 1 is mainly composed of organic compounds, chemical fibers, etc., but is not limited to this, and a suitable material may be selected according to the paint used. You just have to choose. The thickness of the coating pad 1 may be appropriately selected depending on the properties of the coating material (viscosity and the like) and the target coating thickness, but generally 0.5 to 10 mm is preferable in view of the hardness and compressibility of the coating pad. The material of the pedestal 2 having rigidity is not particularly limited, and may be appropriately selected from wood, plastic, metal and the like. The paint can be freely selected according to the application and environment of the product, but if an ultraviolet-curing type (generally called UV paint) is used, an organic solvent is not required, so the coating system is the most favorable for the working environment. be able to.

[0032]

EXAMPLES The present invention will be described more specifically with reference to an example of the apparatus shown in FIG. In this example, the coating pad 1 is impregnated with the coating material by a dipping method. This is a coating pad 1 for a container that has an appropriate depth (the depth where the entire coating pad is almost immersed).
Achieve the purpose by bottoming out. The coating pad 1 can be impregnated with the coating material by pumping the coating material into the coating pad pedestal 2 to impregnate the coating pad 1 from the inside, as shown in FIG.

Next, when the coating pad 1 crosses the curtain-shaped gas jet flow of the gas knife header 5 having a slit nozzle, the surface of the coating pad 1 is wiped to remove excess paint on the surface. At this time, in order to improve the wiping efficiency, it is preferable to give a jet angle to the front. The wiping direction of the coating pad 1 is not particularly limited, but the length across the coating pad 1 in the thickness direction shown in FIG. 4 is short, so the processing time is short and the productivity is high.
However, in this case, the gas knife header 5 having a long slit is required.

Next, the coating pad 1 is pressed against the cut surface of the precoated steel sheet 10 having the masking film 8 attached to the decorative surface. At this time, the pressing operation is performed by the cylinder 15. An example of the pneumatic circuit at that time is shown in FIG. According to this circuit, the cylinder is switched in the pressing direction at the pressure set by the first-stage pressure setting valve 11 (for example, the maximum pressing force (linear pressure) 5 N / cm) with the pressure selection valve 13 being non-excited. , And the contact of the coating pad 1 with the precoated steel plate 10 reaches the maximum pressing force,
When the pressure selection valve 13 is excited, the pressure set by the second stage pressure setting valve 12 (for example, the minimum pressing force (linear pressure) 0.5)
(N / cm) for a predetermined time (about 1 second), the direction switching valve 14 is switched, the cylinder 15 is retracted, and the coating pad 1 is separated from the pre-coated steel sheet 10, thereby ending a series of pressing coating operations. .

In order to perform the movement between the stations for performing the series of processes, the movement for the gas wiping under the gas knife header 5, and the posture and the positioning operation of the pressing operation of the coating pad 1, the coating operation is performed. Attach the pad 1 to the paint pad base 2 and attach it to the robot's hand 2.
If it is attached to 0, it is possible to realize all the operations (including the oblique pressing with the inclination d) with the simplest device configuration. In order to absorb the deviation between the robot operation accuracy and the positioning accuracy of the pre-coated steel sheet to be coated, as shown in FIG. 4, the coating pad base 2 and the cylinder 15 are coupled by the rotation support pin 16 and cut. It is desirable to have a structure in which the coating pad 1 can rotate following the contact in the longitudinal direction of the surface.

When the length of the coating pad 1 is shorter than the length of the coating cut surface of the target precoated steel sheet, the pressing coating is repeated with a slight overlap,
All that is necessary is to paint the entire length. Further, when the cut surface to be coated is a curved surface, the coating pad should have the same bend. For example, on the cut surface having the curvature at the opening corner portion, as shown in FIG. 10, a series of pressing coating similar to the above is performed as the corner coating pad 3 having the same curvature. Of course, one robot can be equipped with multiple and various types of coating pads to switch between them, or multiple coating pads can be operated simultaneously with fluid pressure (reaction forces can be canceled by simultaneously operating in opposite directions on opposite sides). Or
Multiple robots may be used for cooperative work. In the present embodiment, the pressing force of the coating pad 1 is switched by pneumatic pressure, but the mechanical spring mechanism shown in FIG. 7 can be used to perform the same movement, or a composite mechanism of these. Also,
The force control pressing mechanism described above may be a method of moving the pre-coated steel plate 10 without moving the coating pad 1. Therefore, even if the support mechanism of the pre-coated steel plate 10 is provided with a multi-step pressing force setting mechanism and a moving mechanism, the same effect is obtained. is there.

[0037]

As described above, according to the present invention, when the cut surface (edge portion) of the precoated steel sheet is partially coated, automatic coating is easy, low cost, high efficiency and high quality of several tens of μm.
It is a coating method and device that enables local coating with a uniform thickness and a uniform thickness. This improves the rust prevention ability of products using pre-coated steel sheets, and is beautiful and low cost.
In addition, the use of precoated steel sheet products with excellent recyclability can be greatly expanded, and it is an industrially valuable invention.

[Brief description of drawings]

1 is a diagram showing the basic steps of the method of the present invention.

FIG. 2 is a diagram showing oblique pressing from the cutting burr side of the method of the present invention.

FIG. 3 is a perspective view showing reflow with warm air after coating and before drying / curing according to the method of the present invention.

FIG. 4 is a diagram illustrating an example of a basic constituent device for coating a cut surface and an operation example thereof in a perspective view according to the present invention.

FIG. 5 is a diagram showing an example of a pneumatic circuit in two-stage pressing according to the present invention.

FIG. 6 is a diagram showing an example of a pressure / time chart in the two-step pressing according to the present invention.

FIG. 7 is a diagram showing an example of a two-stage pressing mechanism using a spring according to the present invention.

FIG. 8 is a diagram showing an example of a coating pad of the present invention in which a non-woven fabric is wrapped with a woven outer cover.

FIG. 9 is a diagram showing an example of a seepage-type coating pad for supplying paint from the inside according to the present invention.

FIG. 10 is a diagram showing an example of the configuration of a coating pad for a corner portion of the present invention.

[Explanation of symbols]

 1 Paint Pad 1-1 Woven cloth paint pad 1-2 Non-woven cloth paint pad 2 Paint pad base 3 Corner paint pad 4 Paint 5 Gas knife header 7 Hot air generator 8 Masking film 9 Steel plate cutting burr 10 Pre-coated steel plate 11 1st 1st stage pressure setting valve 12 2nd stage pressure setting valve 13 Pressure selection valve 14 Direction switching valve 15 Cylinder 16 Rotation support pin 20 Robot hand 21 1st stage spring 22 2nd stage spring

Claims (9)

[Claims] 1. A masking film is attached to at least the outer surface of a product (hereinafter referred to as a decorative surface) of a steel plate (hereinafter referred to as a pre-coated steel plate) which has been coated with a final product in a flat plate state, and the cut surface is coated. In the method for coating a cut surface of a precoated steel sheet, after impregnating a coating pad made of a sponge or a non-woven fabric and / or a woven fabric with a coating material, the surface of the coating pad is wiped with gas to remove excess coating material, and A method for coating a cut surface of a precoated steel sheet, which comprises pressing a coating pad against the cut surface of the precoated steel sheet while controlling the force. 2. When the coating pad is pressed against the cut surface of the precoated steel sheet while controlling the force, two or more setting values of the pressing force are provided, and the final coating step (the pressing step immediately before the coating pad is separated from the cut surface of the precoated steel sheet). )so,
The method for coating a cut surface of a precoated steel sheet according to claim 1, wherein the pre-coated steel sheet is pressed and held for a predetermined time at a set value of a pressing force smaller than the maximum pressing force. 3. When the coating pad is pressed against the cut surface of the precoated steel sheet while controlling the force, the inclination d = 1/100 with reference to the direction perpendicular to the cut surface of the precoated steel sheet.
The method for coating a cut surface of a precoated steel sheet according to claim 1 or 2, wherein the coating pad is pressed and moved from a direction inclined by 1/3. 4. The coating material applied to the cut surface is flattened by reflowing with hot air after finishing the application of the coating material to the cut surface by the coating pad and before drying or curing the coating material. The method for coating a cut surface of a precoated steel sheet according to any one of claims 1 to 3, wherein 5. A coating device for coating a cut surface of a precoated steel sheet having a masking film attached to at least the decorative surface of the precoated steel sheet, wherein the coating pad is made of sponge or non-woven fabric and / or woven fabric, and the coating pad Immersion of paint impregnation and / or pumping to inner surface
It has a mechanism for exuding, a mechanism for wiping and removing excess paint on the surface of the coating pad with a gas (gas knife), and a mechanism for pressing the coating pad against the cut surface of the precoated steel plate while controlling the force. A cutting surface coating device for precoated steel sheets, which is characterized in that 6. The coating pad is made of a non-woven fabric inside, and at least a surface of an outer skin of the coating pad which comes into contact with a cut surface of a precoated steel sheet is covered with a woven fabric, and further, the non-woven fabric and the pedestal having rigidity. The apparatus for coating a cut surface of a precoated steel sheet according to claim 5, wherein the apparatus is attached to the. 7. A multi-stage press mechanism in which the pressing mechanism of the coating pad against the cut surface of the precoated steel sheet is a pressing mechanism using a fluid pressure cylinder, and the pressing pressure of the coating pad during pressing coating can be controlled in the circuit of the fluid pressure cylinder. The cut surface coating device for precoated steel sheet according to claim 5 or 6, wherein a pressure setting circuit is provided. 8. The pressing mechanism of the coating pad against the cut surface of the precoated steel plate is a pressing mechanism by a mechanical spring mechanism connected in multiple stages in parallel and / or in series, and the mechanical spring mechanism has a spring output of Depending on the mutual movement stroke between the pad and its holding device, it has a mechanism that changes in multiple stages by releasing or re-restraining the spring force in sequence, whereby the coating pad during pressing coating. 7. The apparatus for coating a cut surface of a precoated steel sheet according to claim 5 or 6, wherein the pressing pressure of is variable. 9. The pressing mechanism for pressing the coating pad against the cut surface of the pre-coated steel plate is configured by combining the pressing mechanism by the fluid pressure cylinder according to claim 7 and the pressing mechanism by the mechanical spring mechanism according to claim 8. The cut surface coating device for precoated steel sheet according to claim 5 or 6, characterized in that.