JP3242990B2 - Method and apparatus for supplying paint to die coater - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and an apparatus for supplying a paint to a die coater, and more particularly to a method and an apparatus for supplying a paint applicable to a die coater for precision coating.

[0002]

2. Description of the Related Art Conventionally, the use of a die coater is limited to a thick film coating or a high-viscosity coating due to restrictions on manufacturing accuracy of a coating head (roll, bearing, die body, etc.) and gap control accuracy. I was The paint supplied to the die is usually accommodated in a container such as a drum and handled, and the container does not have a special paint outlet for convenience of recycling or the like. The structure is such that a suction pipe is inserted from above to take out the paint. Therefore, the supply of the paint to the die is performed by a supply pump such as a gear pump provided with the discharge port connected to the die, and one end located in the paint housed in the paint container and the other end being the supply pump described above. This has been done using a paint supply device mainly composed of pipes connected to the suction ports of the above, and a simple strainer or filter provided in a flow path formed therefrom.

[0003]

Recently, a die coater for precision coating has been developed with an improvement in the manufacturing accuracy of a coating head and an increase in coating speed. However, a die coater for precision coating is required to have high precision in the amount of coating, but cannot be coped with a conventional paint supply apparatus using a supply pump with low quantitativeness such as a gear pump. Also, conversely,
The metering pump requires a long time for priming work (work for priming) and the like, which is not efficient, and further hinders a pipe washing operation performed when the paint is changed. The present invention has been made in view of the above circumstances, and its purpose is to
It is an object of the present invention to provide a method and an apparatus for supplying a paint to a die coater which can efficiently perform a priming operation and the like and can exert sufficient quantitativeness.

[0004]

That is, the present invention relates to a method and an apparatus for supplying a paint to a die coater, and the gist of each invention is as follows. The gist of the first invention is that a self-priming supply pump composed of a diaphragm pump, a snake pump or a gear pump is used for sucking paint from an upper part of a paint container (1) by a metering pump (7) and supplying the paint to a die (11). (2) is arranged to form a circulation path between the paint container (1) and the self-priming supply pump (2), and the paint container (1) is formed.
A metering pump (7) is arranged at a position lower than the liquid level of the paint contained therein, the suction side thereof is connected to the circulation path, and a self-priming supply pump (2) is driven to drive the circulation. Metering pump by filling the road with paint (7)
To perform a priming operation of the paint, and then, after the self-priming supply pump (2) is stopped, drive the metering pump (7) to supply the paint to the die (11). Paint supply method. The gist of the second invention is that a paint container (1), a self-priming supply pump (2) composed of a diaphragm pump, a snake pump or a gear pump, and one end of which is located in the paint contained in the paint container (1). And a pipe (3) having the other end connected to the suction port of the self-priming supply pump (2), one end positioned in the paint contained in the paint container (1), and the other end including the self-priming supply pump. (2) a circulation path composed of a pipe (4) connected to the discharge port, and a paint passage contained in the paint container (1) downstream of the self-priming supply pump (2) in the circulation path. Branch pipe (5) provided at a position (a) below the liquid level
And a suction port connected to the branch pipe (5) and a discharge port connected to the die-side pipe (6), and provided at a position below the liquid level of the paint contained in the paint container (1). And a metering pump (7) for supplying paint to the die coater.

Hereinafter, the present invention will be described with reference to the accompanying drawings. 1 to 3 are explanatory diagrams showing an example of a paint supply device to a die coater according to the present invention. FIG. 1 is an explanatory diagram showing a state of priming paint to a metering pump, and FIG. Explanatory diagram showing the work state of filling paint into piping and the like,
FIG. 3 is an explanatory diagram showing a work state of a constant supply of the paint to the die.

[0006] In the coating method using a die coater, the coating material supplied into the die (11) of the die coater is distributed by a manifold, extruded from a slit into a thin film, and the surface of a running sheet (not shown) is coated. How to The method and apparatus for supplying paint to a die coater according to the present invention can be used as is in the conventional die coating method as described above. Accordingly, various known paints are used as the paint, and examples of the sheet include a metal thin plate, a resin sheet, and a composite plate of a metal thin plate and a resin sheet.

[0007] In the paint supply method of the present invention, a metering pump (7) and a self-priming supply pump (2) are used. As the metering pump (7), a Zenith pump is usually used, and such a pump generally has low self-priming property but high quantitative property. As the self-priming supply pump (2), a diaphragm pump, a snake pump or a gear pump is usually used, and such a pump generally has high self-priming but low quantitativeness.

[0008] The paint supply method of the present invention utilizes the above-described metering pump (7) and the self-priming supply pump (2) in a skillful combination. That is, a circulation path is formed between the paint container (1) and the self-priming supply pump (2), and the metering pump (7) is located below the liquid level of the paint contained in the paint container (1). And the suction side thereof is connected to the circulation path. Then, the self-priming supply pump (2) is driven to fill the circulation path with the paint to prime the metering pump (7) with the paint, and then the self-priming supply pump (2) is stopped. Thereafter, the metering pump (7) is driven to supply the paint to the die (11).

According to the paint supply method of the present invention, when the paint is sucked from the upper part of the paint container (1) by the metering pump (7) and supplied to the die (11), the self-priming supply pump (2) is used. The prime operation to the metering pump (7) can be efficiently performed by driving, and the paint can be supplied to the die with high accuracy by driving the metering pump (5) thereafter. Moreover, the metering pump (7) such as a Zenith pump needs to structurally avoid idling,
According to the paint supply method of the present invention, since the metering pump (7) is driven after the priming operation, the metering pump (7) is driven.
Is virtually avoided.

The paint supply method of the present invention can be carried out by the paint supply device of the present invention shown in FIGS.
A paint supply device according to the present invention includes a paint container (1), a self-priming supply pump (2), and a self-priming supply pump having one end positioned in the paint contained in the paint container (1) and the other end. (2)
(3), one end of which is connected to a paint container (1)
A circulation path, a branch pipe (5), and a metering pump (7), each of which is located in the paint housed therein and has the other end connected to the discharge port of the self-priming supply pump (2). Mainly composed of

The branch pipe (5) is located downstream of the self-priming supply pump (2) in the circulation path and below the liquid level (a) of the paint contained in the paint container (1). )
It is provided in. The metering pump (7) has a suction port connected to the branch pipe (5), a discharge port connected to the die-side pipe (6), and a liquid level of the paint contained in the paint container (1). Is provided at the position. Then, the metering pump (7) starts driving after the paint is filled in the circulation path.

In a preferred embodiment of the paint supply apparatus of the present invention, the paint container (1) is provided with a stirrer (not shown) to prevent the paint components from aggregating. 4) At each end in the paint container (1),
A wire mesh (not shown) having an appropriate opening is arranged to remove foreign matter, aggregates, and the like in the paint. Die side piping (6)
A wire mesh (not shown) having an appropriate opening is provided between the die (11) and the die-side pipe (6) immediately before the die (11).
Are arranged, and the foreign matter, agglomerates and the like in the paint are more reliably removed.

In a preferred embodiment of the paint supply device of the present invention, the self-priming supply pump (2) in the circulation path is provided.
A bypass pipe (8) branching from a position (b) upstream of the branch pipe (5) and upstream of the branch pipe (5) and connected to the die-side pipe (6), and a valve ( 9) is provided. The valve (9) is opened after the paint is filled in the circulation path, and is closed after the operation of the metering pump is started.

Further, in the paint supply device of the present invention,
As a preferred embodiment, a valve (10) is provided between the self-priming supply pump (2) and the position (a) or between the positions (a) and (b) in the circulation path.
If a bypass pipe (8) is provided, the valve (1
0) is provided between the position (a) and the position (b). The valve (10) is at least a metering pump (7)
Is closed after the start of the drive, but may be closed after the circulation path is filled with paint.

Each pipe of the paint supply device of the present invention is made of a material having corrosion resistance to paint and necessary strength. Generally, from the viewpoint of simplicity of cleaning, sanitary pipe,
Teflon-lined piping is recommended.

In the paint supply device of the present invention, various control mechanisms can be adopted to achieve automation. For example, a load cell scale (not shown) is controlled by a control system for the purpose of measuring the amount of paint remaining in the paint container (1) to start and stop a supply signal, and monitoring and recording the amount of paint used. Can be partly incorporated. In addition, a high-precision inverter motor or the like is used to drive the metering pump (5), and the amount of paint supply is calculated according to the conditions such as the coating speed and the coating film, thereby automatically driving the metering pump (5). It can also be controlled. Of course, depending on the required coating accuracy, a manual transmission can be used for drive control of the metering pump (5). In addition, the open / close switching of the self-priming supply pump (2) and the valves (9) and (10) can be automatically controlled by using a timer circuit or the like.

The flow of paint in the paint supply device of the present invention is as follows. <Priming operation of paint to metering pump (see FIG. 1)> By driving the self-priming supply pump (2), the paint container (1), the pipe (3), the self-priming supply pump (2), and the pipe (4). ) Is filled with paint. As a result, the branch pipe (5) is also filled with the paint, and the prime work of the paint to the metering pump (7) is efficiently performed. During this time, the metering pump (7) is stopped. The valve (9) provided with the bypass pipe (8) is closed, and the valve (10) is open.

<Work for Filling Paint into Die-Side Piping and the Like (See FIG. 2)> The above-described work for filling is performed as a preferred embodiment. By opening the valve (9), a part of the paint circulating in the circulation path is efficiently filled into the die (11) through the bypass pipe (8) and the die-side pipe (6). Is done.

<Quantitative Supply of Paint to Die (see FIG. 3)> The quantitative supply of paint to the die (11) is performed by a quantitative pump (7).
Is started with high precision through each flow path of the paint container (1), the pipe (4), the branch pipe (5) and the die-side pipe (6). And the valves (9) and (10)
After the metering pump (7) is driven, it is closed.

<Piping Cleaning Operation> The paint container (1) is changed to a solvent container, and the cleaning is performed according to the operations shown in FIGS. As the solvent, a known solvent such as a thinner can be used. Such a pipe cleaning operation can be efficiently performed by the self-priming supply pump (2) having a large self-priming property.

[0021]

EXAMPLES Hereinafter, the present invention will be described in more detail with reference to examples, but the present invention is not limited to the following examples unless it exceeds the gist of the present invention. Example 1 Using the paint supply apparatus shown in FIGS. 1 to 3, the paint was extruded in a thin film form from the slit of the die (11) to coat the surface of the continuously-run coated sheet. <Specifications of paint supply device> Paint container (1): Contains 120 liters of commercially available paint having a viscosity of 360 cp Self-priming supply pump (2): Diaphragm pump (capacity: 48 liters / min) Piping (3): 4 m long

Piping (4): Length 1 m, head 1 m (at minimum liquid level) Branch piping (5): Length 0.1 m Die-side piping (6): Length 6 m, head 1 m (at minimum liquid level) Metering pump (7): Zenith pump (capacity: 1 liter / min) Pipe (8): length 0.1 m Die (11): slit clearance 0.3 mm, coating width 1 m Is also 19 mm.

<Sheet to be Coated> The thickness between the aluminum sheets having a thickness of 0.19 mm is 3.
Composite board (1.1 m width) sandwiching a 62 mm polyethylene sheet.

First, the paint was primed to the metering pump by driving the self-priming supply pump (2). After the self-priming supply pump (2) is driven, the circulation path is filled with the paint in about 2 minutes and the branch pipe (5) is also filled with the paint to prime the paint to the metering pump (7). Work has been completed. Next, the valve (9) is opened, and the valve (10) is opened.
Was switched to a closed state, thereby filling the die-side pipe (6) with paint. About 1 minute after the valve was switched, the paint flowed out of the slit of the die (11). Next, the drive of the self-priming supply pump (2) is stopped, the valve (9) is switched to the closed state, and the metering pump (7) is driven, so that the metering supply of the paint to the die (11) is performed. Work started. As a result, a coating film having a uniform thickness and a good surface condition was formed.

Next, the driving of the metering pump (7) is stopped,
The paint container (1) was switched to a thinner container to perform a pipe cleaning operation. First, the circulation path was cleaned by keeping the valve (9) closed, switching the valve (10) to the open state, and driving the self-priming supply pump (2).
Next, by driving the metering pump (7), the inside of the metering pump (7) was washed. Next, the valve (9) was switched to the open state, the metering pump (7) was stopped, and the valve (10) was switched to the closed state to clean the die-side pipe (6). Next, the drive of the self-priming supply pump (2) was stopped, the valve (9) was switched to a closed state, and the inside of the fixed quantity pump (7) was cleaned by driving the fixed quantity pump (7). .

COMPARATIVE EXAMPLE 1 In Example 1, the valves (9) and (10) were closed and the metering pump (7) was driven without using the self-priming supply pump (2). We tried the quantitative supply of paint. Since the metering pump (7) only idled and could not suck the paint in the paint container (1), the driving of the metering pump (7) was immediately stopped.

[0027]

According to the present invention described above, there is provided a method and apparatus for supplying a paint to a die coater capable of efficiently performing a prime work and the like and exhibiting sufficient quantitativeness. The industrial value of the present invention is great.

[Brief description of the drawings]

FIG. 1 is an explanatory view showing an example of a paint supply device of the present invention, and is an explanatory view showing a work state in which paint is primed to a metering pump.

FIG. 2 is an explanatory view showing an example of the paint supply device of the present invention, and is an explanatory view showing a work state of filling paint into a die-side pipe and the like.

FIG. 3 is an explanatory view showing an example of a paint supply device of the present invention, and is an explanatory view showing a work state of a constant supply of paint to a die.

[Explanation of symbols]

 1: paint container 2: self-priming supply pump 3: pipe 4: pipe 5: branch pipe 6: die side pipe 7: metering pump 8: bypass pipe 9: valve 10: valve 11: die

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int. Cl. ⁷ , DB name) B05C 5/02 B05C 11/10 B05D 1/26 B05D 3/00

Claims (4)

(57) [Claims] 1. A paint container (1) by means of a metering pump (7).
When the paint is sucked from the upper part and supplied to the die (11), a self-priming supply pump (2) is arranged to provide a circulation path between the paint container (1) and the self-priming supply pump (2). A metering pump (7) is formed at a position below the level of the paint contained in the paint container (1), and the suction side thereof is connected to the circulation path. Prime the paint to the metering pump (7) by driving 2) to fill the circulation path with the paint, and then stop the self-priming supply pump (2), and then turn off the metering pump (7). A method for supplying paint to a die coater, wherein the paint is supplied to a die (11) by being driven. 2. A paint container (1), a self-priming supply pump (2), one end of which is located in the paint contained in the paint container (1), and the other end of which is a self-priming supply pump. A pipe (3) connected at one end to a paint housed in the paint container (1) and a pipe (4) connected at one end to a discharge port of a self-priming supply pump (2). ), And at a position (a) downstream of the self-priming supply pump (2) in the circuit and below the liquid level of the paint contained in the paint container (1). Branch pipe (5)
And a suction port connected to the branch pipe (5) and a discharge port connected to the die-side pipe (6), and provided at a position below the liquid level of the paint contained in the paint container (1). And a metering pump (7). 3. A self-priming supply pump in a circulation path.
A bypass pipe (8) branching from a position (b) upstream of the branch pipe (5) and upstream of the branch pipe (5) and connected to the die-side pipe (6); 3. The apparatus for supplying a paint to a die coater according to claim 2, wherein (9) is provided. 4. A valve (10) provided between the self-priming supply pump (2) and the position (a) or between the positions (a) and (b). 4. The paint supply apparatus for a die coater according to 3.