JP2003200084A - Method and apparatus for feeding coating material - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method and an apparatus for feeding a coating material by which, even if a high viscous coating material is used, the coating material is surely fed to a coating apparatus without causing solid liquid separation. <P>SOLUTION: The coating material feeding apparatus is provided with a coating material tank 2 for storing the high viscous coating material, a solvent tank 6 for storing a dilution solvent, a mixing apparatus 11 for mixing the high viscous coating material with the dilution solvent, a flow control pump 5 for feeding the high viscous coating material from the solvent tank 6 to the mixing apparatus 11 and a solvent pump 9 for feeding the dilution solvent from the solvent tank 6 to the mixing apparatus 11. The coating material tank 2 is a pressure tank for forcibly feeding the high viscous coating material by compressed air, and the flow control pump 5 is provided for quantifying the flow of the high viscous coating material forcibly fed from the coating material tank 2 and feeding to the mixing apparatus 11. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a coating material supply method and a coating material supply device, and more particularly, to a coating material supply method and a coating material supply method capable of diluting a high-viscosity coating material to a coating-appropriate viscosity and coating it on an object to be coated. Regarding the device.

[0002]

2. Description of the Related Art As a conventional paint supply device, for example, 2
There is known a configuration in which various kinds of liquids are supplied by a pump, merged, mixed by a mixer, and then supplied to a coating device such as a coating gun (Patent Document 1). This paint supply device has 2
When the viscosities of the liquids are different, the low-viscosity liquid having poor pumping efficiency is constituted by a pressure tank so that the low-viscosity liquid can be pressure-supplied, whereby the accuracy of the mixing ratio of the two liquids can be improved. I am trying to increase.

[0003]

[Patent Document 1] Japanese Patent Laid-Open No. 6-294379 (No. 2-
(Page 4, Figure 2)

[0004]

However, when the above-mentioned paint supply device is used, there arises a problem that the supply of the paint to the coating device becomes extremely difficult depending on the type of the paint.

For example, when a high solid content coating material having a coating material solid content of about 70 to 100% is used, it is difficult to flow the coating material in a pipe with a normal pump due to its high viscosity, and it is mixed with a diluting solvent. However, there is a problem in that it cannot be diluted to a desired viscosity.

For this reason, when the high-viscosity paint is diluted and supplied to the coating apparatus, conventionally, it has been conventionally diluted with a diluting solvent to a coating-appropriate viscosity in a tank filled with the paint.

However, if the paint is diluted in the tank in advance, solid-liquid separation due to sedimentation of the pigment or powder easily occurs in the tank or in the pipe to the coating device, and the desired viscosity cannot be adjusted. there were. Further, in order to avoid solid-liquid separation, if the paint in the tank is constantly stirred or the paint in the pipe is made to flow, not only the running cost increases, but also the deformation of the pigment and the change of the particle size distribution occur, There is a problem that the tint of the coating film changes with time.

The present invention has been made to solve such a problem. Even when a high-viscosity paint is used, the paint can be reliably applied to a coating device without causing the problem of solid-liquid separation. An object of the present invention is to provide a paint supply method and a paint supply device which can be supplied to

[0009]

The object of the present invention is to supply a high-viscosity paint from a paint tank to a mixing device, to supply a diluting solvent from a solvent tank to the mixing device, and in the mixing device. Mixing the high-viscosity paint and a diluting solvent, and supplying the coating device, the step of supplying the high-viscosity paint to the mixing device,
This is achieved by a paint supply method including a step of quantifying the flow rate of the high-viscosity paint pressurized and compressed by compressed air from the paint tank by a flow rate adjusting pump and supplying the quantified flow rate to the mixing device.

Further, the object of the present invention is to provide a paint tank for storing a high-viscosity paint, a solvent tank for storing a diluting solvent, a mixing device for mixing the high-viscosity paint and a diluting solvent, and the paint tank to A flow rate adjusting pump for supplying high-viscosity paint to the mixing device and a solvent pump for supplying diluting solvent from the solvent tank to the mixing device are provided, and the paint tank pressurizes and pumps the high-viscosity paint by compressed air. The flow rate adjusting pump is a pressure tank, and is achieved by a paint supply device that quantifies the flow rate of the high-viscosity paint pressure-fed from the paint tank and supplies the quantified flow amount to the mixing device.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION The actual mode of the present invention will be described below with reference to the accompanying drawings. FIG. 1 is a schematic configuration diagram of a paint supply device according to an embodiment of the present invention.

As shown in FIG. 1, the paint supply device has a pressure tank 2, a solvent tank 6 for storing a diluting solvent, and a mixing device 11 for mixing and dispersing the paint and the diluting solvent as main components. I have it.

The pressure tank 2 is not particularly limited as long as the paint can be pressure-fed by compressed air, but in the present embodiment, a cartridge type tank is used. That is, the pressure tank 2 is configured such that the cylindrical paint tube 1 can be attached and detached therein, has a discharge port 2a on one end side (right side in the drawing), and an injection port 2b on the other end side (left side in the drawing). By supplying compressed air into the pressure tank 2 through the inlet 2b, the paint tube 1 contracts, and the paint contained in the paint tube 1 is pushed out from the discharge port 2a. As described above, by using the paint tube extrusion type as the pressure tank 2, it is possible to eliminate the cleaning work inside the tank.

A cartridge type tank is shown in FIG.
It is also possible to adopt a piston push-out type in which a piston 2c is slidably provided in a cylindrical pressure tank 2 as shown in, and the pressure tank is pressed by pressing the piston 2c by the action of compressed air. The paint filled in 2 can be extruded.

For extruding the paint from the pressure tank 2, instead of supplying compressed air from the outside through the inlet 2b as in this embodiment, a valve is provided near the outlet 2a and the pressure tank 2 is used. It is also possible to preliminarily be configured so that compressed air can be enclosed therein and the valve is opened.
Further, the pressurizing tank 2 may be configured such that a plurality of paint tubes 1 can be simultaneously installed so that the paint to be supplied can be appropriately selected. The paint tube 1 may be a disposable type, or may be configured to be refillable by using a known paint filling device. Further, when considering color change of the paint, it is preferable to provide a cleaning device for cleaning the inside of the paint flow passage between the suction port 4 and the discharge port of the coating device 14. This cleaning device is configured to be able to supply cleaning thinner and flushing air from the vicinity of the suction port 4 toward the coating device 14, and by alternately discharging cleaning thinner or flushing air, Can be washed. As a result, the color can be changed without discarding the paint simply by replacing the paint tube 1 with another color.

A discharge port 2a of the pressure tank 2 is connected to a suction port 4 of a flow rate adjusting pump 5 via a quick joint 3. As in the present embodiment, it is preferable that the pressure tank 2 and the flow rate adjustment pump 5 be directly connected without interposing a pipe or the like.

The flow rate adjusting pump 5 is connected to the manifold 10, and when it is rotationally driven by the drive motor 12, it sends the supplied paint under pressure to the manifold 10. The drive motor 1 supplies paint to the manifold 10.
By controlling the number of revolutions of the flow rate adjusting pump 5 by the control of 2, it can be quantitatively performed.

Examples of the flow rate adjusting pump 5 include a snake pump, a screw pump, a piston pump, a gear pump and the like, which may be appropriately selected according to the type of paint. For example, when using a powder slurry paint, it is preferable to use a snake pump in consideration of the deformation of the pigment.

The solvent tank 6 is connected to the manifold 10 via a strainer 8 and a solvent pump 9. The diluted solvent in the solvent tank 6 is sucked up through the strainer 8 by the operation of the solvent pump 9, and the manifold 10
Is supplied to. Examples of the solvent pump 9 include a plunger pump, a diaphragm pump, and a gear pump, and it is preferable that the diluent solvent can be quantitatively supplied. The solvent tank 6 may be a cartridge type tank like the pressurizing tank 2, and may be configured to be capable of pressurizing and feeding with compressed air as needed. In addition, when an additive such as a curing agent is supplied, it is possible to provide a tank separately and connect it to the manifold 10.

The manifold 10 is connected to a mixing device 11, and the paint and the diluting solvent supplied into the manifold 10 are uniformly mixed and dispersed in the mixing device 11 and adjusted to have a viscosity suitable for coating. The adjusted paint is supplied to a painting device 14 such as a painting gun or a bell-type painting machine.

As the mixing device 11, a static mixer is used in this embodiment, but when atomization or low viscosity is required, as shown in FIG.
A power mixer 1 capable of stirring and mixing a coating material by a screw-shaped movable element 15a that is rotationally driven by
5 can be used as a mixing device. In particular, when using a two-pack type high solids coating material (solid content is about 70 to 100%) (more preferably, when using a two-pack type urethane resin high solids coating material), a power mixer Can be preferably used, and the frictional heat generated by stirring and mixing can reduce the viscosity of the mixed paint to such an extent that it can be applied. When a powder slurry paint is used, the power mixer can disperse the powder in the slurry up to the primary particles.

The flow path length from the mixing device 11 to the inlet of the coating device 14 is preferably 20 to 30 cm at the maximum so that the coating material does not settle when the spraying of the coating device 14 is stopped. In addition, when the flow path length is longer than this, it is preferable to form a circulation path.

Next, a method for supplying the coating material to the coating apparatus using the above-mentioned coating material supplying apparatus will be described. This paint supply device can be particularly preferably used when the high-viscosity paint is diluted to a coating-appropriate viscosity and supplied to the coating device.

The high viscosity paint is, for example, acrylic resin paint, polyester resin paint, urethane resin paint,
Epoxy resin paints, melamine resin paints, etc.
Preferably about 1.5-30 Pa · s, more preferably about 2-30 Pa · s, even more preferably about 3-25 Pa · s.
It is a paint having a viscosity of (measured by a cone-plate type E-type rotational viscometer). If the viscosity of the paint is too high, it becomes difficult to supply the paint even if the paint supply device of the present embodiment is used. On the other hand, if the viscosity of the paint is too low, the pigment tends to settle, which is not preferable.

The high-viscosity paint may be a one-pack type paint or a two-pack type paint used by mixing a curing agent at the time of use. Further, these paints may contain an extender pigment, a coloring pigment, a bright pigment, etc., in addition to the resin component.

The form of the high-viscosity paint is a solution form, a dispersion liquid form,
Examples thereof include emulsion, paste, and slurry. The slurry paint includes a mixture of powder paint and a medium. The concentration of the paint solid content contained in the high-viscosity paint varies depending on the form of the paint and the type of resin, but can be about 40 to 100%. As a more specific example, in the case of a powder slurry coating, the coating solid content is about 40 to 50%, and in the case of a solution or paste coating, the concentration of the coating solid content is 70 to 50%.
It is about 100%.

The diluting solvent depends on the paint used.
An organic solvent, water, or a mixture thereof can be used, and may contain an additive such as a dispersant, if necessary. Examples of the dispersant include a dispersing resin and a surfactant. When the high-viscosity paint is a two-component type, a curing agent is used together with the diluting solvent. In the present embodiment, first, the high-viscosity paint is filled in the pressure tank 2,
The solvent tank 6 is filled with the diluted solvent. When using a two-component type coating material, the curing agent may be stored in the solvent tank 6 together with the diluting solvent, or the curing agent may be stored in a tank provided separately from the solvent tank 6 and may be supplied in a separate stream from the diluting solvent. The curing agent may be supplied to the manifold 10 by the passage.

When supplying the coating material to the coating apparatus, first, the compressed air is applied to the pressure tank 2 and the flow rate adjusting pump 5 is operated. The paint pressed in the pressure tank 2 is extruded from the discharge port 2 a, then the flow rate is quantified by the flow rate adjusting pump 5, and the paint is supplied to the manifold 10.

The pressure of the compressed air supplied to the pressure tank 2 at the time of supplying the paint depends on the viscosity of the paint and the discharge performance of the flow rate adjusting pump 5, but from the viewpoint of improving the accuracy of the paint flow rate, for example, 1 to 2 MPa. It is preferably about the same. If the pressure of the compressed air is too high, the paint may leak from the flow rate adjusting pump 5 and the paint may be discharged excessively. On the other hand, if the pressure of the compressed air is too low, cavitation may occur in the flow rate adjusting pump 5. However, the flow rate of the paint may be insufficient.

By operating the solvent pump 9 at the same time as the coating material is supplied, the diluent solvent is supplied from the solvent tank 6 to the manifold 10 at a constant flow rate. The paint and the diluent solvent supplied to the manifold 10 are mixed by the mixing device 11
The mixed paint is supplied to the coating device 14 after being mixed in, and the mixed coating material is sprayed from the coating device 14 toward the object to be coated.
In order to promote atomization of the mixed paint to be sprayed, ultrasonic vibration can be applied to the supplied paint in the supply passage from the mixing device 11 to the coating device 14 or in the coating device 14.

As described above, according to the paint supply device of this embodiment, the high-viscosity paint can be pressurized and pressure-fed by compressed air, quantified by the flow rate adjusting pump, and the paint can be supplied to the mixing device. Therefore, even a high-viscosity paint can be reliably supplied to the coating device. For example, even if a paint such as a powder slurry paint is used, the solid content of which tends to settle when diluted to a coating-appropriate viscosity. It is possible to accurately adjust the viscosity to a desired viscosity without causing the problem of liquid separation.

[0032]

EXAMPLES In the paint supply device shown in FIG.
A powder slurry paint having a viscosity of 3 Pa · s at 5% was filled in the pressure tank 2 and a water solvent was filled in the solvent tank 6, and the mixed paint was supplied to the coating gun. As a result, the mixed paint having a solid content of 35% could be supplied to the coating gun without causing the problem of solid-liquid separation, and good coating could be performed on the object to be coated.

Further, a high solid content clear base material having a viscosity of 26 Pa · s was filled in the pressure tank 2 and a curing agent having a viscosity of 2.5 Pa · s was filled in the solvent tank 6, and the mixed paint was supplied to the bell type coating machine. . As a result, the mixed paint having a mixed viscosity of about 5 Pa · s could be supplied to the bell-type coating machine, and good coating could be performed on the object to be coated.

[0034]

As is apparent from the above description, according to the present invention, even when a high-viscosity paint is used, the paint can be reliably supplied to the coating device without the problem of solid-liquid separation. be able to.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram of a paint supply device according to an embodiment of the present invention.

FIG. 2 is a cross-sectional view showing a modified example of a pressure tank in the paint supply device shown in FIG.

3 is a cross-sectional view showing a modified example of the mixing device in the paint supply device shown in FIG.

[Explanation of symbols]

1 paint tube 2 Pressurized tank 3 quick joint 4 suction port 5 Flow rate adjustment pump 6 solvent tank 8 strainers 9 solvent pump 10 manifold 11 Mixing device 12 Drive motor 14 Coating equipment

Claims (4)

[Claims] 1. A step of supplying a high-viscosity paint from a paint tank to a mixing apparatus, a step of supplying a diluting solvent from a solvent tank to the mixing apparatus, and a step of mixing the high-viscosity paint and the diluting solvent in the mixing apparatus The step of supplying the high-viscosity paint to the mixing device comprises quantifying the flow rate of the high-viscosity paint pressure-fed by compressed air from the paint tank with a flow rate adjustment pump. A paint supply method including a step of supplying to the mixing device. 2. A paint tank for storing a high-viscosity paint, a solvent tank for storing a diluting solvent, a mixing device for mixing the high-viscosity paint and the diluting solvent, and a high-viscosity paint from the paint tank to the mixing device. A flow rate adjusting pump for supplying and a solvent pump for supplying a diluting solvent from the solvent tank to the mixing device are provided, and the paint tank is a pressurizing tank for pressurizing and feeding a high-viscosity paint by compressed air, The adjustment pump is a paint supply device that quantifies the flow rate of the high-viscosity paint pressure-fed from the paint tank and supplies it to the mixing device. 3. The paint supply device according to claim 2, wherein the paint tank is configured such that a paint tube can be attached and detached, and the paint tube can be contracted by the action of compressed air to discharge the paint. 4. The coating material supply device according to claim 2, further comprising a coating device connected to the mixing device.