JP3207106B2 - Coating equipment for water-soluble paint - Google Patents

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 a water-soluble paint, and more particularly to a water-soluble coating apparatus for spraying a paint onto a work conveyed continuously in the coating booth without exhausting the coating booth. The present invention relates to a coating device for paint.

[0002]

2. Description of the Related Art Conventionally, a coating apparatus that continuously transports an object to be coated (work) by using a transport means such as an overhead conveyor, and paints the transported workpiece using a paint spraying device or the like. Is widely used.

As an example of such a coating apparatus, as shown in FIG. 4, for example, a work 42 suspended along a track 40 of an overhead conveyor is enclosed in a tunnel-shaped coating booth 44 in which a work is suspended. A coating apparatus 46 having a paint spray nozzle 46a when passing in a direction perpendicular to the paper surface;
Spray coating of the paint is performed. This type of coating apparatus can individually form a thin coating film on the work 42, and can coat the work 42 in a continuous process by combining with a continuous drying furnace or the like.

A coating apparatus using the coating booth 44 efficiently collects paint mist that has not adhered to the workpiece 42 and minimizes the discharge of paint mist outside the coating apparatus. Air supply fan 48 at 44
4 and a discharge port 50 having an exhaust fan 50a to form a flow of paint mist.
The painting booth 44 is divided into a painting area 44a and an exhaust area 44b by an isolation wall such as a curtain 52 as shown in FIG. The paint mist collides with the curtain 52 to collect the paint mist. Further, a shower device 54 using circulating water or the like is provided in the exhaust area 44b,
The paint mist is collected by circulating water to reduce paint discharge, and paint is collected and reused.

[0005]

However, with the above-described recovery method, the paint mist cannot be sufficiently recovered, and may be discharged to the outside of the coating apparatus or to the atmosphere. Therefore, it is necessary to separately provide an exhaust filter or the like, which causes a problem that the size of the apparatus is increased and the cost is increased. Therefore, there is a demand for a coating apparatus capable of collecting paint mist without exhausting.

If the paint booth 44 is not evacuated, the paint mist that has not adhered to the work 42 floats inside the paint booth 44 and re-adheres to the work 42 on which the coating has been formed. There is a problem that the thickness becomes unstable and quality is deteriorated, or the thickness of the film is attached to the track 40 or the coating device 46 of the overhead conveyor provided in the coating booth 44, and the function thereof is deteriorated. In addition, there is a problem that the paint mist flows out of the entrance and exit of the painting booth 44 due to the formation of an airflow accompanying the continuous spray of the paint mist.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned conventional problems, and an object of the present invention is to prevent floating and discharge of paint mist in the same manner as in the case of exhausting air without exhausting the paint booth. In addition, it is an object of the present invention to provide a water-based paint coating apparatus capable of reducing the size of the coating apparatus.

[0008]

According to a first aspect of the present invention, there is provided a coating apparatus for a water-soluble paint for spraying a water-soluble paint onto a continuously conveyed work. Transport means for transporting the workpiece, an airless injection nozzle for injecting a water-soluble paint to the workpiece, a tunnel-shaped booth through which the workpiece can pass, and a workpiece holding portion of the transport means on an inner wall surface; It is characterized by including a non-exhaust painting booth having a spray nozzle, and a spray control unit for intermittently spraying a water-soluble paint on the same work a plurality of times.

According to this configuration, since the water-soluble paint is intermittently sprayed into the same work in a plurality of times, the air flow accompanying the paint spray becomes intermittent, and when the air flow is stopped, the paint mist is caused by its own weight. Fall . As a result, the painting booth
The paint mist inside is prevented from floating, and the paint booth exhaust
It becomes unnecessary. Further, the paint mist can be efficiently collected at the lower surface of the paint booth without flowing out of the entrance of the paint booth.

In order to achieve the above object, a second invention provides a coating apparatus for a water-soluble paint according to the first invention.
The non-exhaust painting booth is characterized by having a liquid supply means for forming a liquid film on the inner wall surface.

Here, the liquid film is, for example, water or a liquid containing water as a main component. According to this configuration, the paint mist that is to adhere to the wall surface of the non-exhaust painting booth flows down with the liquid, and the paint can be reliably collected with the liquid. The recovered liquid is separated into a paint and a filtrate by a filtration device or the like, and the paint can be reused for coating and the filtrate can be reused for a liquid film. As a result, the paint mist does not adhere to the wall surface, so that the maintenance property of the non-exhaust painting booth is improved, and the paint and the liquid can be efficiently reused.

According to a third aspect of the present invention, there is provided a coating apparatus for a water-soluble paint according to the first and second aspects of the present invention, further comprising an openable / closable shielding means at an entrance side of the non-exhaust coating booth. It is characterized by.

Here, the shielding means is made of synthetic resin, rubber material, or the like, and is turned up by the conveying force of the work, exhibits a sheet-like curtain to be divided or a door shape which can be divided at the center or the like. It has a structure that closes immediately. According to this configuration, the influence of the air flow changes in the surrounding non-exhaust coating booth can be minimized, no discharge
It prevents the formation of airflow in the air painting booth and prevents the paint mist from floating.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a conceptual perspective view of a coating apparatus for a water-soluble paint of the present embodiment, and FIG. 2 is a schematic cross-sectional view cut in a direction orthogonal to a workpiece conveying direction. The workpiece 10 to be coated is suspended by a suspension arm 12a of an overhead conveyor 12 as a transport means, and transported along a track 12b in the direction of arrow A in FIG. Also, a tunnel-shaped non-exhaust painting booth 14 for performing a painting operation on the work 10 is shown in parallel with the track 12b. Workpiece 10 is not discharged in the water-soluble paint coating device.
A paint mist is sprayed on the work 10 at a predetermined position while passing through the air coating booth 14 to form a coating film of a predetermined thickness on the work 10.

As shown in FIGS. 1 and 2, the exhaust-free painting booth 14 has a drain tank 16 at an arbitrary position at the lower end, for example, at the center. Drainage of a water shower described later flows into the drain tank 16. Therefore,
The cross-sectional shape of the non-exhaust painting booth 14 perpendicular to the conveying direction of the work 10 is narrowed down. Further, it is desirable that the lowest part of the non-exhaust painting booth 14 is inclined so as to descend toward the drain hole 16a. With this configuration, the liquid of the water shower (for example, water) flows down the inner wall surface of the no-emission coating booth 14 and is well collected in the drain tank 16.

Also, the ceiling wall 14 of the non-exhaust painting booth 14
a is formed with an opening groove 14b through which the suspension arm 12a of the overhead conveyor 12 can pass. The width of the opening groove 14b is such that the paint mist that has not adhered to the work 10 does not flow out, and the suspension arm 12 is used to minimize the drop of dust and the like and the influence of the external environment.
It is preferable that the width is slightly wider than the thickness of a, and it is preferable to perform sealing with a flexible member such as a resin or a rubber material as necessary. Further, the shape and size of the inlet 14c and the outlet 14d of the work 10 are desirably such that they can pass through the work 10. Therefore, the opening amount may be adjusted according to the size of the work 10.

Also, the side wall surface 14 of the non-exhaust painting booth 14
The paint injection nozzle 20 of the airless coating device 18 is provided at e and 14f. In the present embodiment, four paint spray nozzles 20 are provided so that paint mist can be sprayed from both sides of the work 10. Airless coating equipment
Because paint is sprayed from a small nozzle hole by high pressure,
Since compressed air is not contained in the paint mist, the generation of airflow due to the paint mist injection can be minimized, and the paint mist is less scattered and the coating efficiency is good. Also,
A large amount of paint is sprayed. High viscosity paint can be sprayed. There are advantages such as good feeding into the concave shape.

A characteristic feature of the present embodiment is that a paint mist is sprayed a plurality of times by an airless coating device on a single work continuously passing through a no-emission coating booth to form a coating film on the work. .

The airless coating apparatus 18 can accurately and intermittently control the spray timing and the spray time of the paint mist under the control of the spray control unit 22 which is internally or externally connected. For example, when the transport speed of the work 10 is 2 m / min, the spraying and stopping of the paint mist are repeated at one second intervals. Therefore, in the case where the opening of the application pattern of the paint mist is about 300 mm in diameter (actually elliptical because the nozzles are arranged at an angle) and the work 10 is a cube having a side of 300 mm, 5 points for the same point of the work 10 Since the paint mist can be sprayed about once, a sufficient coating film thickness can be secured.

Since the paint mist is injected intermittently, the flow of the paint mist is intermittent. As a result of the intermittent air flow, the paint mist falls under its own weight when the injection stops. That is, even in the case of airless injection, when continuous injection is performed, an airflow is generated, and paint mist starts to float in the non-exhaust coating booth 14 and re-adheres to the work 10, and the inlet 14 c, the outlet 14 d of the work 10, the opening groove 14
However, the paint mist can be prevented from floating or flowing out by performing the intermittent injection.

By performing the intermittent injection in this way, the generation of airflow is prevented, and the paint mist is allowed to fall under its own weight, so that the paint mist floating time and floating distance can be reduced. As a result, the distance from the paint spraying position to the work inlet 14c and the outlet 14d can be reduced, and the size of the non-exhaust painting booth 14 can be reduced. The length of the spray time and the stop time of the coating film mist are arbitrary.However, by increasing the stop time with respect to the spray time, it is possible to prevent the paint mist from being wound up, and to further reduce the floating of the paint mist. it can.

In the present embodiment, the dropped paint is collected together with the liquid (eg, water) by the water shower as described above. The shower nozzle 24 of the water shower is formed by forming a large number of holes in the surface of the pipe, and is disposed at the upper end of the side wall surfaces 14e and 14f of the no-emission coating booth 14 in parallel with the work transfer direction. The shower nozzle 24 is connected to the drain tank 16 via a pump 26, a plurality of valves 28, and a filtering device 30. Therefore, the liquid accumulated in the drain tank 16 together with the paint mist is appropriately filtered by the filtration device 30 to be separated into the filtrate and the paint. The paint is returned to a paint tank (not shown) of the airless painting device 18 and reused for painting. On the other hand, the filtrate is pumped up by the pump 26 and supplied to the shower nozzle 24 to be used for collecting the paint. Therefore, the filtrate circulates in the system as a circulating liquid.

The shower nozzle 24 has side walls 14e,
14f, circulating fluid at a suitable pressure (low pressure)
To release. The circulating liquid flows down the entire side wall surfaces 14e and 14f along the wall surface and is supplied so as to form a water film on the wall surface. The side wall surface 14 is formed by the water film.
e, prevent paint mist from adhering to 14f, and at the same time, cause paint mist to flow down to the lower part of the no-emission paint booth.
Further, the circulating liquid flows into the drain tank 16 together with the paint mist from a drain hole 16a provided at the lower part of the non-exhaust painting booth and is reused.

By arranging the water shower in this manner, the paint can be smoothly collected and the paint mist can be prevented from being rolled up, and the paint mist can be applied to the wall surface of the non-exhaust paint booth 14. Adhesion can be prevented and maintainability can be improved.

FIGS. 3A and 3B show examples of a nozzle cover 32 disposed around the paint spray nozzle 20 when a water shower is used. This nozzle cover 32
Is not particularly necessary when the amount of protrusion from the wall surface of the paint spray nozzle 20 is sufficient, but as shown in FIG. 3A, when the amount of protrusion of the paint spray nozzle 20 is small, or as shown in FIG. When the paint spray nozzle 20 is moved up and down, left and right in order to perform wide-area painting with one nozzle as described above, the circulating liquid is arranged so as not to affect paint mist spray and paint mist quality. When the nozzle moves as shown in FIG. 3B, a seal 34 made of resin, rubber, or the like is provided to prevent only the paint mist from entering the movable portion, and is provided to project only the moving paint spray nozzle 20. It is desirable.

It is desirable to provide an opening / closing shielding means at the entrance 14c. For example, a sheet-like curtain 36 made of a resin or rubber material is provided as a shielding means for the entrance 14 c so that the curtain is turned up when the work 10 enters, or the curtain 36 separates at an arbitrary position and passes through the work 10. May be allowed. On the other hand, the outlet 14d is a work 1 in a wet state after the coating film is formed.
Since 0 passes through, it is not preferable to provide a shielding means that is opened and closed by the work 10 like the entrance 14c,
A door that opens and closes according to external control may be provided as necessary. By providing such a shielding means, no
It is possible to minimize the influence of the change in the airflow around the exhaust coating booth 14, prevent the formation of the airflow in the non-exhaust coating booth due to the external environment, prevent the paint mist from floating, and prevent the paint mist from flowing out. Prevention can be further improved.

By providing the above-described configuration in the non-exhaust painting booth, an airless type paint spray nozzle having a capacity of 200 cc / min for a cubic work having a conveying speed of 2 m / min and a side of 300 mm is provided. when forming a coating film of about 20μm intermittently driven at 1 second intervals, no
The size of the exhaust painting booth is length (work transfer direction) 3
m, width 2m, height 1.5m, for water-soluble paints without paint mist floating even without exhaust system A coating device can be obtained.

In this embodiment, an example has been described in which four paint spray nozzles are provided, two on each side, that is, a total of four paint spray nozzles.
It is desirable to appropriately change the number of arrangements, the arrangement positions, and the arrangement pattern according to the size and shape of the work and the thickness of the coating film to be formed. Further, the suspension arm of the overhead conveyor may be rotatable, and the work may be rotated to spray a paint mist from one side to form a coating film on the entire work.

In this embodiment, an example in which the paint and the liquid of the water shower are reused has been described. However, the present invention may be applied to a disposable type water-soluble paint coating apparatus.

[0030]

As described above, according to the present invention,
Since the water-soluble paint is intermittently sprayed into the same work in a plurality of times, the airflow accompanying the paint spray becomes intermittent, and the paint mist drops due to its own weight when the airflow stops.
As a result, even without a forced exhaust device using a filter, etc., the floating of paint mist inside the non-exhaust painting booth is reduced, and it is prevented from flowing out of the entrance and exit of the non-exhaust painting booth and re-adhering to the work. In addition, it is possible to efficiently collect the paint and downsize the water-soluble paint coating apparatus.

[Brief description of the drawings]

FIG. 1 is a conceptual perspective view of a water-soluble paint coating apparatus according to an embodiment of the present invention.

FIG. 2 is a schematic sectional view of a water-soluble paint coating apparatus according to an embodiment of the present invention.

FIG. 3 is a perspective view showing a nozzle shower of the water-soluble paint coating apparatus according to the embodiment of the present invention.

FIG. 4 is a conceptual diagram of a coating apparatus using a conventional coating booth.

[Explanation of symbols]

10 workpieces, 12 overhead conveyors, 14 nothing
Exhaust painting booth, 16 drain tank, 18 airless painting device, 20 paint spray nozzle, 22 spray controller, 2
4 Shower nozzle, 32 nozzle cover.

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int. Cl. ⁷ , DB name) B05B 9/00-9/08 B05B 12/00-13/06 B05B 15/00-15/12

Claims (3)

(57) [Claims] 1. A water-soluble paint coating apparatus for spraying and spraying a water-soluble paint on a continuously conveyed work, comprising: a conveying unit for conveying the work; and a water-soluble paint sprayed on the work. An airless injection nozzle, and a tunnel-like booth through which the work can pass,
A non-exhaust coating booth having a work holding part of the transfer means and the spray nozzle on an inner wall surface, and a spray control part for intermittently spraying a water-soluble paint on the same work a plurality of times. Coating equipment for conductive paint. 2. The coating apparatus for water-soluble paint according to claim 1, wherein said non-exhaust coating booth has a liquid supply means for forming a liquid film on an inner wall surface. 3. The coating apparatus for water-soluble paint according to claim 1, further comprising a shielding means which can be opened and closed at an entrance side of the non-emission coating booth.