JP2001009332A - Coating apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a coating apparatus capable of suppressing disorder of a spraying pattern due to the drying of a coating material in the case of random coating. SOLUTION: A plurality of coating material droplets of a coating material able to be diluted with water are attached to the surface of a board. At that time, the control system 11 controls the ambient conditions in the periphery of the nozzle tip end as to keep the relative humidity about 70% by supplying water to the ambient atmosphere from a humidifying mechanism 13 on the basis of the sense data from a humidity sensor 14. Consequently, the coating material able to be diluted with water is prevented from deposition on the nozzle tip end in the dry atmosphere.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a coating apparatus for performing random coating on a building material board, and more particularly to a coating apparatus suitable for an exterior building material board made of a cement-based mixed material.

[0002]

2. Description of the Related Art In recent years, ceramic building material boards have been frequently used as exterior building materials having excellent design properties, and those having an uneven pattern or pattern imitating natural stone on the outer wall surface have been commercialized.
Further, in order to reduce costs, proposals have been made to improve design by devising a coating method.

[0003] This type of building material board is formed into a predetermined shape by, for example, pouring a slurry-type cement-based mixed material into a mold, or performing suction dehydration on a filter cloth and applying a patterning process. (Curing) and drying processes or, if necessary, grooving and the like, followed by painting.

[0004] In general, the design of a board is often a tile having a large number of rectangular projections and linear grooves. By randomly painting only the tile surface, which is the rectangular projection, the product has a natural texture. When an injection nozzle is used in such a coating method, random coating can be performed without contacting the board surface.

[0005]

However, in the random coating method using a spray nozzle, there is a problem that the paint dries in a dry atmosphere in winter and deposits on the tip of the nozzle. Specifically, as shown in FIG. 4, in a dry atmosphere in winter, the spray pattern is disturbed within 1 to 2 hours after the coating of the building material board 10 by the coating nozzle 25 is started, and the coating quality is deteriorated. FIG. 4 shows a case where the spray pattern is asymmetrical.

Accordingly, an object of the present invention is to improve such a problem and to provide a coating apparatus capable of suppressing disturbance of a spray pattern due to drying of a paint at the time of random painting.

[0007]

Means for Solving the Problems To achieve the above object, the present inventor of the present application has reported that the use of a water-dilutable paint causes the moisture in the paint to evaporate and disappear in a dry atmosphere. Assuming that various experiments were conducted, it was found that if the area around the tip of the nozzle was humidified, the spray pattern was not disturbed even after long-time coating, and the present invention was reached.

That is, the present invention relates to an apparatus for performing coating by applying a water-dilutable paint to a surface of a board having a large number of rectangular projections and linear grooves by a spray nozzle. Humidifying means for humidifying the atmosphere around the tip of the nozzle, humidity measuring means for measuring the relative humidity around the tip of the spray nozzle, and humidity measurement when spraying a water-dilutable paint on the board surface using the spray nozzle. Control means for controlling the driving of the humidifying means so that the relative humidity around the nozzle tip becomes a predetermined value based on the measurement value of the means.

Further, the present invention is characterized in that the relative humidity around the nozzle tip is controlled to be 70 ± 10%, or that the nozzle tip is formed in a tapered shape.

According to such a configuration, the water in the paint at the nozzle tip is prevented from evaporating and disappearing, and the spray pattern disturbed by the deposition of water-dilutable paint at the nozzle tip is suppressed. However, normal coating operation can be continued for a long time. Further, the water droplets generated by the humidification can be blown off at the same time as the paint is sprayed, and can be attached to the target portion of the object together with the paint.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described below with reference to the accompanying drawings. FIG. 1 is a diagram illustrating a random coating apparatus for building material boards according to an embodiment of the present invention.

First, the configuration of the apparatus will be described. The control system 11 performs a conveying operation of the building material board 10 to be coated, a coating operation of a water-dilutable paint described later by the coating nozzle 25,
The operation of the entire apparatus such as the humidifying operation by the humidifying mechanism 13 is controlled. Specifically, it is composed of a personal computer or a workstation including a CPU, a RAM, a ROM, and the like. The CPU executes a predetermined process based on various types of sensor information based on operation inputs and command signals in accordance with a control program stored in the ROM in advance. The ROM stores a control program for the entire apparatus, a program for performing random coating, and an atmosphere at the tip of the nozzle having a predetermined humidity (relative humidity 70%).
%) Is stored. The RAM stores necessary data and is used as a work area. Here, the reason why the relative humidity is set to about 70% is that when the relative humidity is 80% or more, it is not suitable as a use environment of a drive motor or the like, and the life of the device is shortened due to rust or the like.

The humidifying mechanism 13 includes a drive motor (not shown),
This is a steam fan type humidification mechanism including a thermistor, a temperature sensor, and the like, which humidifies the vicinity of the tip of the coating nozzle 25.

The exhaust mechanism 12 is disposed to face the humidifying mechanism 13 and exhausts paint particles floating around the tip of the coating nozzle 25 to the outside by rotating an exhaust fan by a drive motor (not shown). This is to prevent the floating paint particles from re-adhering to the surface of the apparatus, especially around the nozzle, from drying and hardening, and to maintain stable coating conditions.

The humidity sensor 14 is located near the tip of the coating nozzle 25 (specifically, 100 to 200 mm from the tip of the nozzle).
Distant position), constantly detects the relative humidity around the tip of the coating nozzle 25, and sends out a detection signal to the control system 11. For example, an impedance change type using a ceramic dry and wet material, Alternatively, it is constituted by an impedance change type or capacitance change type sensor using a polymer thin film dry and wet material.

The coating nozzle (spray nozzle) 25 sprays a water-dilutable paint on the board surface to apply the paint, and the width direction of the building material board 10 (the direction perpendicular to the transport direction).
Are fixedly arranged at predetermined intervals. As shown in FIG. 2, each of the coating nozzles 25 has a coating material supply section 25a for constantly filling the water-dilutable coating material under pressure, and a tip section 25b that opens and closes at a predetermined timing by turning on / off a solenoid (not shown). Is provided. The tip portion 25b has a tapered substantially conical shape. This is because water droplets generated by humidification are blown off from the nozzle tip at the same time as the paint is sprayed, and adhere to the target portion of the object together with the paint.

With this configuration, when spray coating is performed, humidification control is performed based on detection information from the humidity sensor 14 so that the relative humidity around the nozzle tip becomes 70%.

The belt conveyor 15 is a belt in which the inertia is small, and a toothed belt (timing belt) that does not cause slippage of a transmission portion with respect to a load change is wrapped around a driving roller 16. It is transported to the coating position at the timing.

The transport conveyor 27 is disposed adjacent to the downstream of the coating position and continuously transports the building material board 10 to a subsequent process.

The positioning / transporting mechanism including the belt conveyor 15 is a servo mechanism and is configured as shown in FIG. In FIG. 3, the urging means 18 rotatably urges one side in the conveying direction of the building material board 10 toward the belt conveyor 17 by the air pressure of the air cylinder, and balances the building material board 10 so as not to deviate from the conveying path. And hold it. The belt conveyor 17 is driven in synchronization with the belt conveyor 15. The reason for this configuration is to prevent the building material board 10 on the belt conveyor 15 from skewing or slipping due to unevenness on the surface thereof, thereby preventing the positioning in the XY direction from becoming poor. The board position sensor 19 is constituted by an optical reflection sensor, and detects that the building material board 10 has reached a predetermined position upstream of the painting position.

With such a configuration, the belt conveyor 1
After the board position sensor 19 detects the tip of the building material board 10 placed on the board 7, the driving motor (servo motor or the like) is further conveyed by a predetermined amount.
Reaches the painting position, and the painting process is performed by the painting nozzle 25.

In this embodiment, the humidifying mechanism 13 and the like constitute humidifying means, the humidity sensor 14 constitutes humidity measuring means, and the control system 11 constitutes control means.

Next, the steps before painting will be described. The building material board 10 is a ceramic exterior material used for the outer wall, and at the time of molding, the slurry-type cement-based mixed material is poured into a mold or supplied in a layer form on a filter cloth, and A known method (for example, JP-B-56-3)
After suction and dehydration by the method described in Japanese Patent Application Laid-Open No. 3129), the board is shaped into a predetermined board shape, cured (cured) and dried, or subjected to grooving if necessary, and then painted.

At the time of coating the building material board 10, first, for example, a single-color base is coated on at least one surface side of the board body 11 using a coating means such as a spray nozzle (a coating nozzle) (a flow coater or the like). After performing, forcible drying by heating for a predetermined time in a normal heating and drying means,
Or let it dry naturally.

Next, paint droplets of a predetermined water-dilutable paint are attached to the surface of the building material board 10 sent to the painting position by the above-described positioning / transporting mechanism, and a large number (a plurality of) of rectangles are formed on the board surface. To form a painted area. At this time, the control system 11 supplies water to the atmosphere from the humidifying mechanism 13 based on the detection information from the humidity sensor 14 to reduce the atmosphere near the nozzle tip to a relative humidity of 70 ± 10.
% To control the humidification mechanism 13.

The water-dilutable paint is a paint whose fluidity is enhanced by water dilution, such as a water-soluble paint, an emulsion paint, and a water-dispersible paint. The water-dilutable paint has a different color from the paint used for the base coat.

In the present embodiment, the atmosphere near the nozzle tip is humidified, but it may be configured to humidify a wider area. For example, it is good also as a structure which can be humidified so that the surface of the building material board 10 may be covered.

According to this embodiment, even in a dry atmosphere in winter, the vicinity of the nozzle tip is maintained at a predetermined relative humidity (more preferably, about 70% relative humidity).
Dispersion of the water-dilutable paint on 5b prevents the spray pattern from being disturbed, and it is possible to continue normal coating operation for a long time. Specifically, when the area around the nozzle tip was humidified to a relative humidity of 70 ± 10%, no disturbance of the spray pattern occurred even after continuous coating for 7 hours. In addition, the coating nozzle 25 is not limited to the continuous coating operation.
In the case of the coating operation in which the ON / OFF operation is intermittently performed, the disturbance of the spray pattern can be suppressed for a long time.

According to the present embodiment, as a servo mechanism for transporting the building material board 10 to the painting process, there are provided belt conveyors 15 and 17 for transporting the building material board 10 in contact with the bottom surface and one side surface thereof. Since the urging means 18 which slides the building material board 10 from one side to the other side is provided, the building material board 10 can be normally conveyed and accurately positioned at the painting position.

[0030]

According to the present invention, when a water-dilutable paint is sprayed onto the board surface by using a spray nozzle (painting nozzle) in the random coating, the relative humidity around the nozzle tip becomes a predetermined value (preferably). Is controlled to be 70 ± 10%), so that the water-dilutable paint is prevented from depositing at the nozzle tip in a dry atmosphere, and the spray pattern is not disturbed even if the paint is applied for a long time. .

Also, since the tip of the nozzle is preferably formed in a tapered shape, water droplets generated by humidification are blown off simultaneously with spraying paint from the tip of the nozzle, and adhere to a target portion of an object together with paint. Can be.

[Brief description of the drawings]

FIG. 1 is a diagram showing a configuration of a coating apparatus according to an embodiment of the present invention.

FIG. 2 is a diagram showing a tip shape of a coating nozzle according to an embodiment of the present invention.

FIG. 3 is a diagram showing a positioning / conveying mechanism according to the embodiment of the present invention.

FIG. 4 is a diagram showing disturbance of a spray pattern in a dry atmosphere.

[Explanation of symbols]

 Reference Signs List 10 building material board 11 control system 12 exhaust mechanism 13 humidifying mechanism 14 humidity sensor 15, 17 belt conveyor 16 drive roller 18 biasing means 19 board position sensor 25 painting nozzle 25a paint supply section 25b tip section 27 transport conveyor

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Hiroyuki Asai 25 Asahi Glass Co., Ltd., Kazu-gun, Kashima-gun, Ibaraki Prefecture (72) Inventor Kei Yamamoto 2-1-2 Marunouchi, Chiyoda-ku, Tokyo Asahi Glass (72) Inventor Noboru Sone 2-1-2 Marunouchi, Chiyoda-ku, Tokyo Asahi Glass Co., Ltd. F-term (reference) 4D075 AA01 AA57 AA65 AA86 AA90 DA06 EA06 4F035 AA03 BB13 CB13

Claims (3)

[Claims] 1. An apparatus for performing coating by applying a water-dilutable paint to a surface of a board having a large number of rectangular projections and linear grooves by a spray nozzle, the periphery of a tip of the spray nozzle. Humidification means for humidifying the atmosphere of the nozzle, Humidity measurement means for measuring the relative humidity around the tip of the injection nozzle, and the measured value of the humidity measurement means when spraying water-dilutable paint on the board surface using the injection nozzle Control means for controlling the driving of the humidifying means so that the relative humidity around the tip of the nozzle becomes a predetermined value based on the following. 2. The relative humidity around the tip of the nozzle is 70 ±
2. The method according to claim 1, wherein the control is performed so as to be 10%.
Coating equipment as described. 3. The coating apparatus according to claim 1, wherein said nozzle tip is formed in a tapered shape.