JP2002045764A - Method for curtain coating, apparatus for curtain coating, and method for producing cooking utensil - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a process for curtain coating, which, when applied for forming a fluororesin coating film of a water-borne coating material on a metallic pressing to form a frying pan, is nonproblematic in the tendency of the coating material to form bubbles and in a low production efficiency due to the large number of steps otherwise necessary for spraying a water-borne coating material onto a metallic pressing formed before being coated therewith and baking the coating film. SOLUTION: An adoption is made of a coating process comprising allowing a water-borne coating film subjected to an antifoaming treatment to flow down as a curtain and admitting a work W into the curtain, so that the coating with the water-borne coating material can be performed beautifully and highly efficiently without causing the coating material to form bubbles. By this constitution, markedly high efficiency off frying pan production and reduction in its cost can be realized.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a curtain coat coating method, a curtain coat coating apparatus, and a method for manufacturing a cooking utensil which can be used when manufacturing cooking utensils such as frying pans.

[0002]

2. Description of the Related Art In cooking utensils such as frying pans, it is common practice to form a fluororesin-based coating film on the inner surface of the cooking utensil. Use an electric or electromagnetic heater when cooking,
If the release property (non-sticking property) is not so particular, a method of applying a solvent-based paint is used. However, when it is necessary to use heat such as gas at the time of cooking as well as to have good releasability as a main use situation of the cooking utensil, it is preferable to adopt a method of painting with a water-based paint.

In such water-based paints, a surfactant is added in order to form an aqueous dispersion (for dispersing fluorine in water), and as a result, bubbles can be easily generated even by slight stirring or vibration. There was a difficulty in handling that it would occur. Therefore, the procedure for manufacturing a cooking utensil when applying the water-based paint is as follows: a material plate such as aluminum is cut into a predetermined shape (a disc shape or the like), pressed, formed into a container shape, and then oiled. Cleaning and blasting, etc., and applying (spraying) water-based paint with an automatic painting gun, etc.
Thereafter, drying, intermediate coating, top coating and the like are performed, and firing for baking of the water-based paint is performed.

As described above, foaming is suppressed by adopting a method of applying (spraying) a water-based paint by an automatic painting gun or the like. That is, unless application (spraying) by an automatic coating gun or the like is employed, bubbles are generated in the water-based paint, and these bubbles adhere to the painted surface as they are, resulting in a defective coating film. It is.

[0005]

As described above, the procedure for manufacturing a cooking utensil in the case of applying a coating with a water-based paint involves a large number of steps, and there is naturally a limit in improving the manufacturing efficiency. This is largely due to the necessity of previously forming the material plate into a container before painting. That is, in the coating after forming the material plate into a container in this manner, the coating angle by the coating gun is slowly transferred to the container so as to prevent uneven coating and omission of coating for each one. This is because careful painting has to be performed by frequently changing or transporting the container material plate to the installation line of the coating gun group fixed at various angles.

In addition, the method of applying (spraying) a water-based paint with an automatic coating gun or the like sometimes has a coating efficiency of at most about 35% to 50%. Therefore, such a situation has led to an increase in cost as a cooking appliance. The present invention has been made in view of the above circumstances, and in the case of manufacturing cooking utensils, for example, a curtain that can be coated with a water-based paint at a high efficiency without causing foaming without causing foaming. It is an object of the present invention to provide a method of manufacturing a cookware, which provides a coat coating method and a curtain coat coating apparatus, and at the same time, drastically increases the manufacturing efficiency of the cookware to realize a low cost. .

[0007]

In order to achieve the above object, the present invention takes the following measures. That is, in the curtain coat coating method according to the present invention, after performing an antifoaming treatment on an aqueous paint composed of an aqueous dispersion containing a surfactant (such as a fluororesin), the aqueous paint is coated with a predetermined width from above. While flowing down as a curtain curtain with expanse,
The object to be coated is coated with a water-based paint while the object to be coated is passed through the curtain curtain.

The passage of the object through the curtain of water-based paint includes the case where the curtain is moved with the object to be stopped stopped. The above-described defoaming treatment may be performed by passing the aqueous paint through a defoaming filter immediately before flowing down. The curtain coat coating apparatus according to the present invention includes a paint supply unit that supplies the water-based paint to a position higher than the work, and a storage head that temporarily stores the water-based paint from the paint supply unit above the work. A slit-shaped falling nozzle that is provided on the lower surface of the storage head and allows the water-based paint to flow down as a curtain curtain having a predetermined width, and, for the storage head, It is assumed that a defoaming filter is provided in the inside thereof at a position to be a final passage to the downflow nozzle portion.

A paint receiving portion is provided below the flow-down nozzle portion to collect excess paint that has not adhered to the object to be coated, and a circulation path is formed between the paint receiving portion and the paint supply portion or the storage head. In this case, a defoaming filter can be provided also for the outflow portion of the paint receiving portion. Further, a bubble removing portion may be provided for the storage head. The bubble removing portion is for allowing the water-based paint stored inside the storage head to overflow with foam components from above the water surface.

[0010] A method for manufacturing a cooking utensil according to the present invention comprises a raw material forming step of forming a raw material plate of a cooking utensil (a shape and a size are not limited to those finally finished), and a raw material forming step. A pre-treatment step of applying a base treatment to the raw material plate, an inner surface coating step of applying a water-based paint to at least the inner side of the cooking utensil for the raw material plate that has passed through the pre-processing step, It has a firing step of firing the plate and a pressing step of forming the raw material plate having undergone the firing step into a predetermined cooking utensil shape. And
Among these, in the inner surface coating step, the above-described curtain coat coating method of the present invention is performed.

By doing so, it is possible to prevent coating defects due to foaming of the water-based paint. Further, in this method, since the inner surface coating and firing can be completed in advance for the material plate before press forming (that is, in a flat plate state), the production efficiency can be dramatically increased. it can.

[0012]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows an outline of a curtain coat coating apparatus 1 according to the present invention, and FIG. 2 shows an appearance as an example. The curtain coat coating apparatus 1 includes: a support table 2 for holding a material plate W as an object to be coated in a flat state;
And a mechanical unit 4 installed below (eg, without limitation) the side of the support table 2 and the like.

The support table 2 is configured such that an upstream conveyor device 7 and a downstream conveyor device 8 are connected to each other at a predetermined interval from a position below the bridge portion 3. Both conveyor devices 7 and 8 are illustrated as belt conveyors, and are driven synchronously. The speeds of these two conveyor devices 7 and 8 can be changed, whereby the conveying speed of the raw material plate W is adjusted, and as a part of the coating film thickness adjustment.

The bridging section 3 has a storage head 10 and a downflow nozzle 11 provided on the lower surface thereof, as shown in an enlarged view of the internal structure in FIG. The storage head 10 has two strips 12, 13 nestled in a parallel state, and a lateral recess 14 formed in one strip 13 allows both strips 1, 13 to be formed.
A recessed storage space is formed between 2 and 13. A water-based paint flows into the storage head 10 from a supply port 15 provided at one end in the longitudinal direction.

The upper ends of the two strips 12 and 13 are connected to each other by a hinge 16, and one of the strips 12 can be flipped up and turned. Thereby, the storage head 1
0 can be easily cleaned. The falling nozzle portion 11 is provided with each of the strips 12 in the storage head 10,
By attaching a pair of edge plates 17 and 18 to the lower surface portion of 13, a slit-shaped opening is formed between the edge plates 17 and 18. The edge plates 17 and 18 are fixed by mounting bolts 19, respectively, and by loosening them once, the nozzle gap can be adjusted.

That is, the adjustment of the nozzle gap is also a part of the coating thickness adjustment. In such a bridging portion 3, the inside of the storage head 10 is positioned as a final passage to the flow-down nozzle portion 11, that is, a shape (a V-shaped cross section) in which the lower concave portion is rolled up from below. Thus, a defoaming filter 22 is provided. The defoaming filter 22 is formed of a net material or the like, and its opening may be selected in a range of about 60 to 200 mesh depending on the composition of the paint. In the case of using a fluororesin-based aqueous dispersion, it is preferable that the mesh size be 100 to 140 mesh.

The material of the defoaming filter 22 is not particularly limited. For example, stainless steel, plastic,
Paper, cloth, etc. can be used. As shown in FIG. 4, in order to fix the defoaming filter 22 in the storage head 10, an inner fitting frame 25 may be used. The inner fitting frame 25 is a combination of a pair of tension shafts 26 and a spring member 27 for urging the tension shafts 26 in directions away from each other.
The tension shaft 26 includes a core shaft 30 having a threaded portion at least at one end thereof, and a sleeve 31 externally inserted into the core shaft 30.
And a push nut 32 and a lock nut 33 screwed into the threaded portion of the core shaft 30.

The sleeve 31 is formed of an elastic material such as rubber so as to have a diameter larger than that of the push nut 32 and the lock nut 33, and prevents the interference between the sleeve 31 and the defoaming filter 22. . It is preferable to use stainless steel cut bolts for the core shaft 30. That is, the inner fitting frame 25 is pressed against the opposing inner surface of the storage head 10 by the spring member 27 while being in contact with the opposing inner surface of the defoaming filter 22 by the two tension shafts 26 (sleeve 31). The state is fixed by adjusting the screwing degree (adjusting the length of the shaft length) of the protruding nuts 32 on the both protruding shafts 26, and is prevented from being loosened by the lock nuts 33.

The mechanical section 4 includes a paint tank 36 and a pump 3
7, paint supply unit 3 having filter chamber 38 and the like
9 with the paint receiving portion 40 provided between the upstream conveyor device 7 and the downstream conveyor device 8 of the support table 2 and the paint receiving portion 40 and the paint supply portion 39 (the paint tank 36). It is composed of a connecting gutter 41 and the like. That is, the water-based paint stored in the paint tank 36 is supplied to the filter chamber 3 by the operation of the pump 37.
The ink is sent to the storage head 10 through the storage head 8 and flows down from the storage head 10 via the flow-down nozzle 11 as a curtain curtain having a predetermined width.

Accordingly, the base material W conveyed by the support table 2 passes through the curtain curtain, so that the water-based paint is applied with a predetermined thickness. The surplus paint that has not adhered to the material plate W follows a circulation path in which the paint is collected by the paint receiving portion 40 and returned to the paint tank 36 again via the gutter portion 41. As shown in FIG. 1 and FIG.
Is provided with a defoaming filter 45 at an appropriate position of an outflow portion toward the paint tank 36 (for example, a connection portion between the paint receiving portion 40 and the gutter portion 41).

The defoaming filter 45 is formed of a net material or the like, and its opening may be selected in the range of about 60 to 200 mesh depending on the composition of the paint. In the case of using a fluororesin-based aqueous dispersion, it is preferable that the mesh size be 100 to 140 mesh. The material of the defoaming filter 45 is not particularly limited, and for example, stainless steel, plastic, paper, cloth, or the like can be used. As shown in FIG. 5, the defoaming filter 45 may be formed in a cage shape or attached to a cage frame and fixed to a predetermined position.

Further, in the curtain coat coating apparatus 1, as shown in FIG. 1, a bubble removing portion 46 can be provided for the storage head 10, and by providing the bubble removing portion 6, a further layer can be provided. A defoaming effect can be obtained. The bubble removing portion 46 is connected to a foam recovery container 51 from a ceiling portion of the storage head 10 via a communication tube 50 formed of a pipe or a hose. The communication tube 50 is provided with a valve 52. The foam collection container 51 is not necessarily required, and the end of the communication pipe 50 can be directed to a drainage channel (not shown), or can be connected to the paint tank 36 via an appropriate filter.

The communication pipe 50 for the storage head 10
Is not particularly limited as long as it is at or above the water level in the storage head 10. However, it is preferable that the diameter of the communication pipe 50 at least at the connection portion to the storage head 10 is larger. In addition, it is preferable that a transparent portion made of plastic or glass is provided on the whole or a part of the communication tube 50 because the state of bubbles can be visually observed (even if there is dirt, it can be confirmed by irradiation of a backlight).
It is preferable to adopt a type in which the opening and closing amount can be finely adjusted as the valve 52.

By providing such a bubble removing portion 46, when a foam component is generated from the aqueous paint stored in the storage head 10, only the foam component overflows (ie, is removed).
Can be done. Next, a method of manufacturing a cooking utensil (referred to as a frying pan) M using the curtain coat coating apparatus 1 having the above configuration (the curtain coating method and the manufacturing method of the cooking utensil according to the present invention) will be described. First, as a whole flow, this manufacturing method forms a material plate W made of, for example, an aluminum plate or the like in a shape (disc) according to the final shape of the cooking utensil M, as shown in FIG. As shown in FIG. 6 (B), a pre-processing step of subjecting the raw material plate W formed in the raw material forming step to a base treatment by a blast method or the like as shown in FIG. An inner coating step of applying a water-based paint to at least a surface inside the cooking utensil M with respect to the raw sheet W that has undergone the pre-processing step, and a raw sheet W that has passed through the inner coating step as shown in FIG. A firing step (the drawing is for facilitating understanding, and whether or not a burner is used in actual firing is not limited at all) and a firing step as shown in FIG. Material plate W
And a pressing step of forming the same into a predetermined cooking utensil shape.

In the above-mentioned inner surface coating step (see FIG. 2), first, an aqueous paint composed of an aqueous dispersion containing a surfactant (such as a fluororesin) is stored in a paint tank 36, and a pump 37 is operated. Let it. This allows
The water-based paint in the paint tank 36 is supplied to the storage head 10, and while being subjected to the defoaming treatment by the defoaming filter 22, the water-based paint flows down from the downflow nozzle 11 as a curtain curtain having a predetermined width. Then, the support table 2 (the upstream conveyor device 7 and the downstream conveyor device 8) is operated.

As a result, the raw material plate W passes through the curtain of the water-based paint formed by flowing down from the flow-down nozzle 11, whereby the raw material plate W is coated. In such a coating method, the defoaming filter 22
In addition to the removal of the foam by the bubble removal part 46, the removal of the foam component is also performed, so that the coating failure in the raw material plate W due to the foaming of the water-based paint is almost certainly prevented. The surplus paint that has not adhered to the material plate W is returned from the paint receiving section 40 to the paint tank 36 via the gutter section 41 again. As a result, bubbles in the paint are removed, and the suppression of coating defects is further ensured.

Further, with such a coating method, the coating efficiency can be actually increased to about 98%. In this way, as shown in FIG. 7, a cooking appliance M having an aqueous paint film T on the inner surface is obtained. By the way, the present invention is not limited to the above embodiments,
It can be changed appropriately according to the embodiment.

[0028]

As is clear from the above description, in the curtain coat coating method and the curtain coat coating apparatus according to the present invention, in the case of manufacturing cookware, etc., the coating using the water-based paint causes foaming. It is now possible to perform beautifully and efficiently without the need. In addition, in the method for manufacturing a cooking utensil according to the present invention, with the implementation of the curtain coat coating method and the curtain coat coating apparatus, the manufacturing efficiency of the cooking utensil has been dramatically improved, and the cost can be reduced. .

[Brief description of the drawings]

FIG. 1 is a side view showing an outline of a curtain coat coating apparatus according to the present invention.

FIG. 2 is a perspective view showing an appearance of a specific example device corresponding to FIG.

FIG. 3 is an enlarged sectional view taken along line AA of FIG. 2;

FIG. 4 is an enlarged sectional view taken along line BB of FIG. 3;

FIG. 5 is an enlarged perspective view showing a defoaming filter provided in a paint receiving section.

FIG. 6 is a process diagram showing a method for manufacturing a cooking appliance according to the present invention.

FIG. 7 is an immediate sectional view showing an example of a cooking utensil.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Curtain coat coating apparatus 10 Storage head 11 Downflow nozzle part 22 Defoaming filter 39 Paint supply part 40 Paint receiving part 45 Defoaming filter 46 Defoaming part W Material plate

Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat II (reference) B05D 7/24 301 B05D 7/24 301F // A47J 37/10 A47J 37/10 F term (reference) 4B055 AA50 BA28 CA02 FA02 FB36 FC20 4B059 AA03 AB02 CA02 CA14 4D075 AC14 AC84 BB04X BB05Z BB26Z DA06 DB01 DC38 EA06 EB16 EC35 4F041 AB01 BA07 BA32 CA04 4F042 AA20 CA07

Claims (6)

[Claims] An aqueous coating composition comprising an aqueous dispersion containing a surfactant is subjected to a defoaming treatment, and the aqueous coating composition is allowed to flow down from above as a curtain curtain having a predetermined width. A method for coating a curtain coat, wherein the object to be coated is coated with a water-based paint in a state where the object is passed through a curtain. 2. The method for coating a curtain coat according to claim 1, wherein the defoaming treatment is performed by passing the aqueous paint through a defoaming filter (22) immediately before flowing down. 3. A paint supply section (39) for supplying a water-based paint to a position higher than a workpiece, and a storage head for temporarily storing the water-based paint from the paint supply section (39) above the workpiece. (10) and a slit-shaped falling nozzle (11) provided on the lower surface of the storage head (10) to flow down the water-based paint as a curtain curtain having a predetermined width. (10) A curtain coat coating apparatus characterized in that a defoaming filter (22) is provided in the interior thereof as a final passage to the downflow nozzle (11). 4. A paint receiving section (40) below the flow-down nozzle section (11) for collecting surplus paint that is not adhered to an object to be coated.
A circulation path is formed between the paint receiving portion (40) and the paint supply portion (39) to the storage head (10), and a circulation path is formed between the paint receiving portion (40) and the outflow portion of the paint receiving portion (40). 4. The apparatus according to claim 3, further comprising a defoaming filter. 5. The storage head (10) is provided with a bubble removing portion (46) for overflowing a foam component from above the water surface of the water-based paint stored inside the storage head (10). Or the curtain coat coating device according to claim 4. 6. A material forming step for forming a material plate (W) of a cooking utensil, and a material plate (W) formed in the material forming step.
Pre-treatment step of applying a base treatment to the material, an inner surface coating step of applying a water-based paint to at least the inner side of the cooking utensil on the material plate (W) having undergone the pre-treatment step, and a material having passed through the inner surface coating step A baking step of baking the plate (W); and a pressing step of forming the material plate (W) having passed through the baking step into a predetermined cooking utensil shape. A method for manufacturing a cooking utensil, wherein the method for coating a curtain coat according to 2 is performed.