JP4422591B2 - Slide type coating device and coating method using the same - Google Patents

Description

  The present invention is a slide-type coating in which liquid is ejected from a plurality of slits provided on a slide to form a liquid film layer composed of a plurality of liquid films, and this liquid film layer is coated on a moving strip. The present invention relates to a method and a slide type coating apparatus.

  The slide type coating device discharges liquid from a plurality of slits provided on the slide to form a liquid film layer composed of a plurality of liquid films on the slide, and paints on the belt-like object that moves the liquid film layer It is a device to do. As a device that generates a liquid film by a slide type coating method and forms a coating film on a steel plate or a strip, a slide curtain coating device that forms a curtain of a liquid film falling from a slide and applies it on the strip There is a slide bead coating apparatus in which a slide and a strip are close to each other and a multilayer film is directly applied on the strip without forming a curtain.

  A slide type coating apparatus and a coating method using the same have been developed mainly as a photographic film manufacturing technique. Patent Document 1 describes a slide type coating apparatus in which the width of a liquid film layer composed of a plurality of liquid films is constant. Further, in Patent Document 2, a plurality of liquid film layers are constituted by a wide layer and a narrow layer, and are made larger than the width of a strip (called a web) that moves through the wide layer, There has been proposed a method and an apparatus in which the width of the other layer is made smaller than the width of the strip, and only the paint of the wide layer is collected and reused.

  It is considered that the slide-type coating equipment and the coating method can also be used for coating a metal plate, and Patent Document 3 discloses that a plurality of liquid film layers discharged from the slit onto the slide have the same width. It is shown to be painted on a board.

Japanese Patent Publication No.49-24133 Japanese Patent Publication No.62-47075 Japanese Patent Laid-Open No. 06-190335

  As described above, in the slide type coating apparatus conventionally used for the production of photographic films, the width of each layer in the multilayer film as shown in Patent Document 1 is constant, and the width as shown in Patent Document 2 is wide. Those having a layer (also referred to as a wide film) and a narrow layer (also referred to as a narrow film) have been disclosed. The material width of the photographic film is constant, i.e. the width of the coating does not change. Therefore, in the slide type coating apparatus used for photographic film production, it was assumed that the width of the liquid film did not change with time and was always constant.

  By the way, when a slide-type coating apparatus is used for surface coating of a metal plate represented by band steel, the width of the metal plate that is the object to be coated changes frequently. For example, the lot unit of the steel strip is 3 to 30 Ton (1000 to 10,000 m), and the width of the steel strip frequently changes every 10 to 100 minutes even when the line speed is set to 100 m / min.

  Moreover, the range of the steel plate width is 600 mm to 2100 mm, and the range of the width to be changed is extremely wide. In order to keep the liquid film width constant for all the steel plate widths, it is necessary to always maintain the liquid film width corresponding to the widest steel plate width of 2100 mm. For example, when the width of a steel plate changes from a wide width to a narrow width, if the width of the liquid film does not change, the portion of the width of the liquid film formed beyond the width of the steel plate is not painted on the steel plate and is recovered. Will be. However, the liquid film collected after flowing down the width of the steel sheet cannot be reused because the paint that forms the multilayer film is mixed. The amount of paint to be discarded increases. When trying to keep a small amount of paint to be discarded even when painting a narrow steel plate, reduce the width of the liquid film according to the width of the steel plate, and the width of the liquid film formed beyond the width of the steel plate To reduce the amount of paint to be discarded.

  On the other hand, if the width of the liquid film is fixed in accordance with the width of the narrow steel plate, when the width of the steel plate changes from a narrow width to a wide width, if the width of the liquid film does not change, The end of the steel sheet is not painted. This portion of the steel sheet must be recycled as scrap due to poor edge coating, which reduces the yield of the steel sheet. In this case, it is desired to increase the yield of the steel sheet as much as possible by increasing the width of the liquid film according to the width of the steel sheet and adjusting the liquid film to be sufficiently applied to the end of the steel sheet.

  When trying to change the width of the liquid film in a conventional slide type coating device, stop the steel plate running on the coating line, change and adjust the width of the liquid film of the slide type coating device, and then the steel plate again. It is possible to run. However, in the case of a steel plate coating line, a drying furnace for directly drying and reacting the paint is heated at the back of the slide type coating device, and if the travel speed of the steel plate changes, the drying and reaction will occur. The time required changes and the quality of the paint film changes. Therefore, it is necessary to change the width of the coating film without changing the traveling speed of the steel plate.

  The present invention is a slide-type coating apparatus that reduces the decrease in the yield of strips without damaging the soundness of the coating on the coating strip as much as possible when the width of the strips such as steel sheets changes in the coating line, and An object is to provide an apparatus for efficiently changing the width of a liquid film for the purpose of reducing the amount of waste paint as much as possible. The present invention also proposes a method for efficiently changing the width of the liquid film according to the width of the strip such as a steel plate when the width of the strip such as the steel plate is changed in the painting line using the apparatus. For the purpose.

  The present invention presents an apparatus and a method for efficiently changing the widths of a plurality of liquid films discharged from a slit of a slide type coating apparatus onto a slide. For this purpose, the inventors created the shape of a device (hereinafter referred to as “liquid film width adjusting device 4”) that can seal the end of the slit on the slide and move in the width direction. As the material, a material that has good wettability and does not react was selected, and a material that did not scratch the slit was selected. Further, by controlling the flow rate per unit width to be constant during the movement of the liquid film width adjusting device 4, and by stacking these techniques, the end film breakage occurs as the moving speed of the liquid film width adjusting device 4. It has been found that the width of the narrow-width paint can be changed within a few seconds to a few dozen seconds in consideration of the fact that it is within the film formation limit. In addition, the inventors have further devised a method for efficiently using the slide type coating apparatus in which this apparatus is installed in the painting line.

  When the coating is performed by the slide type coating apparatus using the liquid film width adjusting device of the present invention, the thickness of the coating film may be uneven in the width direction. In particular, there was a tendency that the thickness at the width end portion of the coating film was increased. In the present invention, a header end plug movable in the width direction is disposed at the end of the header portion for supplying the liquid to the slit, and the fitting portion in the slit of the liquid film width adjusting device has a depth corresponding to the slit depth. It was found that the thickness of the coating film can be made uniform by providing the thickness.

That is, the gist of the present invention is as follows.
(1) A slide is formed by discharging liquid from a plurality of slits 3 provided on a slide to form a liquid film layer 9 composed of a plurality of liquid films, and applying the liquid film layer 9 onto a moving strip 8 In the mold coating apparatus, an instrument for sealing the end of the slit 3 on the slide provided for the purpose of changing the width of one or more liquid films (hereinafter referred to as “liquid film width adjusting instrument 4”). And the liquid film width adjusting device 4 is movable in the width direction of the slit 3, and a part of the shape of the liquid film width adjusting device 4 is a wedge-shaped flat plate so as to fit into the slit 3. 11 and a mechanism for mechanically moving the liquid film width adjusting device 4 in the lateral direction, and a gap between the slit 3 on the slide and the wedge-shaped flat plate 11 provided on the liquid film width adjusting device fitted thereto. A slide type paint characterized by having a mechanism for adjusting Location.
(2) The slide coating apparatus according to (1) above, wherein the portion of the liquid film width adjusting device 4 facing the slit 3 is made of a metal containing iron.
(3) The slide type coating apparatus has a header portion 5 for supplying a liquid to the slit 3, a header end plug 25 at the end of the header portion, and the header end plug 25 extends in the width direction of the header portion. The slide type coating apparatus according to (1) or (2) above, wherein the slide coating apparatus is movable, and the fitting portion in the slit of the liquid film width adjusting device 4 has a depth corresponding to the slit depth.
(4) The slide type coating apparatus as described in (3) above, which has a mechanism for moving the header end plug 25 in a lateral direction mechanically or by adjusting air pressure.
(5) It has one or both of a mechanism for mechanically moving the liquid film width adjusting device 4 in the lateral direction and a mechanism for mechanically moving the header end plug in the lateral direction, and the moving speed is 5 mm / s or more. The slide type coating apparatus according to any one of the above (1) to (4), wherein the sliding type coating apparatus is 50 mm / s or less.
(6) A width position detection device 14 for detecting the width position of the strip is provided upstream of the moving strip, and the liquid film width adjusting device 4 is based on the width position of the strip 8 detected by the width position detection device 14. The slide type coating apparatus according to any one of the above (1) to (5), wherein the stop position is adjusted.
(7) The collection tank 15 having the partition plate 16 movable in the width direction of the slit 3 is provided at the lower part of the slide 2, and the position of the partition plate 16 can be adjusted based on the position of the liquid film width adjusting device 4. slide type coating apparatus according to any one of the above (1) to (5), characterized in that there.

( 8 ) A coating method using the slide type coating apparatus according to any one of (1) to (7), wherein the moving speed of the liquid film width adjusting device 4 and the discharge flow rate of the paint discharged from the slit A coating method using a slide-type coating apparatus, characterized by controlling the discharge flow rate per unit length to be constant while the liquid film width adjusting device 4 moves in conjunction with the speed.
( 9 ) A coating method using the slide type coating apparatus according to any one of the above (1) to (7), wherein the slide type coating apparatus is installed in a coating line, and is disposed upstream of the coating line. A slide type coating apparatus characterized by installing a width position detecting device 14 for detecting the width position of a steel plate and adjusting the stop position of the liquid film width adjusting device 4 in the slide type coating apparatus based on the detection signal. The painting method used.
( 10 ) A coating method using the slide type coating apparatus according to any one of (1) to (7) above, wherein a plurality of liquids are ejected from a plurality of slits provided on the slide. When forming the liquid film layer 9 made of a film, the width of one or a plurality of liquid films is made wider than the width of the other liquid film to form the liquid film layer 9, and the belt-like material moving the liquid film layer 9 A collection tank 15 having a partition plate 16 movable in the width direction is provided at the lower part of the slide type coating apparatus, and is applied to the bottom of the slide type coating apparatus, and is based on the position of the liquid film width adjusting device 4 in the slide type coating apparatus. A coating method using a slide type coating apparatus, wherein the position of the partition plate 16 is adjusted to separate and collect one or more wide liquid films .

  Even if the width of the belt-like object to be coated by the slide coating apparatus is changed, the coating on the coating belt is sound and the yield reduction of the belt-like object can be reduced. Furthermore, the amount of waste paint can be reduced as much as possible.

  As a device that generates a liquid film by a slide type coating method and forms a coating film on a steel plate or a strip, a slide curtain coating device that forms a curtain of a liquid film falling from a slide and applies it on the strip There is a slide bead coating apparatus in which a multi-layer film is directly applied on a strip without forming a curtain in close proximity to the slide and the strip. In the slide curtain coating apparatus, since the coating film forms a curtain and drops and the speed increases, the coating can be performed at a higher speed than when the slide bead coating apparatus is used.

  Here, a process of generating a liquid film by a slide type coating method and forming a coating film on a steel plate or a strip will be described using an example of a slide curtain coating apparatus shown in FIG. In the example shown in FIG. 8, a narrow liquid film (referred to as narrow film 21) formed by discharging from narrow slits (3b, 3c) and a wide film formed by discharging from wide slit width 3a. The structure of the slit 3 used when forming the multilayer film which consists of a liquid film (it is called the wide film | membrane 20) is shown. A liquid film is generated by supplying a liquid from the header 5 (also referred to as a paint reservoir) to the slit 3 and discharging the liquid from the slit 3 provided on the slide 2. The width of the liquid film to be discharged is determined by the width of the slit 3, and the discharged liquid film is guided on the slide by the edge guide 7 so that the width does not change.

  The liquid film slides down along the slide 2 and sequentially overlaps the liquid film discharged from the slit on the lower side, thereby forming a multilayer liquid film layer 9. The liquid film that freely falls away from the lower end of the slide 2 becomes a curtain. At this time, the wide film 20 is guided by the curtain guide 6 and applied onto the surface of the strip 8 moving under the curtain.

  In the slide type coating apparatus of the present invention, as shown in FIGS. 1 and 2, a movable sealing device is provided at the end of the slit 3 on the slide 2. This sealing device is called a liquid film width adjusting device 4. The liquid film width adjusting device 4 can be moved in the width direction of the slit 3, and the width of the liquid film can be adjusted by moving the device in the horizontal direction. It is possible to change the width of the liquid film of one layer or a plurality of layers by the liquid film width adjusting device 4.

  Regarding the shape of the liquid film width adjusting device 4, it is necessary to pay attention to the following points. First, when changing the width of the liquid film (hereinafter referred to as “when the liquid film width adjusting device 4 is moved”), the discharge flow rate is also changed. Therefore, it is considered that the coating amount is leaked, and it is necessary to prevent this. Secondly, after the adjustment of the width of the liquid film is completed (hereinafter referred to as “when the liquid film width adjusting device 4 is fixed”), the paint is prevented from leaking from the gap. Thirdly, when the liquid film width adjusting device 4 is moved, paint leakage is prevented and the liquid film width adjusting device 4 needs to move, so that a gap enough to slide is necessary. Fourth, since the liquid film width adjusting device 4 moves frequently for changing the width, the liquid film width adjusting device itself or the slit 3 provided on the slide 2 is not worn and the gap does not change. It is necessary to select a suitable shape and material. Fifth, it is necessary to prevent the liquid from being cured around the liquid film width adjusting device 4 so that the liquid film width adjusting device 4 does not move.

  As the liquid film width adjusting device 4 that satisfies the above functions, the liquid film width adjusting device 4 having the shape shown in FIGS. 1 and 2 can be employed.

  In the liquid film width adjusting device 4 of FIG. 1, a parallel plate 10 is provided so as to fit into the slit as shown in FIG. The interval between the parallel plate 10 and the slit 3 is set to about 100 μm or less. As shown in FIG. 1A, an air cylinder 12 is installed on a liquid film width adjusting device that seals the end of the slit 3 on the slide surface. Further, the liquid film width adjusting device 4 has a structure that can be independently moved by a screw motor 13 connected via an air cylinder 12.

  In the liquid film width adjusting device 4 shown in FIG. 1, when the liquid film width adjusting device 4 is moved, the liquid film width adjusting device 4 and the slide 2 are applied with a pressure that does not cause liquid leakage and is movable. Set between slits 3. For example, using the air cylinder 12 shown in FIG. 1, when the liquid film width adjusting device 4 is moved, the pressure is set so that the liquid does not leak in consideration of the weight of the liquid film width adjusting device 4. May be. Alternatively, a stepping cylinder may be used in place of the air cylinder 12 to adjust the gap so that the liquid does not leak when the liquid film width adjusting device is moved.

  At the time of fixing the liquid film width adjusting device 4, a pressure is set between the liquid film width adjusting device 4 and the slit 3 of the slide so that liquid leakage does not occur completely. For example, the air cylinder may be used to adjust the pressure so that the liquid does not leak completely, as shown in FIG. Alternatively, a stepping cylinder may be used in place of the air cylinder so as to adjust the gap so that liquid leakage does not occur completely.

  The liquid film width adjusting instrument 4 shown in FIG. 2 has a wedge-shaped flat plate 11 as shown in FIG. 2B instead of the parallel flat plate 10 of FIG. Thereby, the gap between the liquid film width adjusting device 4 and the slit 3 of the slide 2 can be freely changed. An air cylinder 12 is provided as shown in FIG. The air cylinder 12 serves as a mechanism for adjusting the distance between the slit 3 on the slide and the wedge-shaped flat plate 11 provided on the liquid film width adjusting device 4 fitted thereto. By changing the pressure of the air cylinder 12, the gap between the slit 3 and the wedge-shaped flat plate 11 can be accurately changed. Moreover, you may change the space | interval of a clearance gap using a stepping cylinder. As a result of adopting such a structure, when the liquid film width adjusting device 4 is moved, a gap that does not cause liquid leakage can be set. Further, the liquid film width adjusting device 4 has a structure that can be independently moved by a screw motor 13 connected via an air cylinder 12. The screw motor 13 is a mechanism for mechanically moving the liquid film width adjusting device 4 in the lateral direction.

  In order to prevent wear between the liquid film width adjusting device 4 and the slit 3, a so-called rubbing structure can be formed between them so that the surface pressure between the liquid film width adjusting device 4 and the slit 3 of the slide 21 can be lowered. You may do it. For example, as shown in FIG. 2 (c), the tip of the liquid film width adjusting device 4 is a wedge-shaped flat plate 11, and the exit of the slit 3 on the corresponding slide is also a tapered slit 19 inclined correspondingly. Alternatively, it may be shaped so that the gaps can be rubbed together.

  The hardening of the liquid occurs when the solvent of the paint accumulated in the gap between the liquid film width adjusting device and the slide slit comes into contact with the atmosphere and evaporates. Therefore, particularly when the liquid film width adjusting device is fixed, this can be prevented if the gap can be accurately reduced. For example, in the structure as shown in FIG. 2, if the wedge-shaped flat plate 11 of the liquid film width adjusting device 4 is moved downward by the air cylinder 12, the space between the slits is narrowed to prevent the paint from hardening. it can.

  Next, the material of the liquid film width adjusting device 4 will be described.

  The items required for the material of the portion facing the slit 3 of the liquid film width adjusting device 4 are good sliding between the liquid film width adjusting device 4 and the slit 3, and do not wear the slit 3 of the slide. In addition to being controllable, paints and materials with good wettability are required.

  For that purpose, when the iron film is used for the liquid film width adjusting device 4, the wettability with the paint is improved and the end film is not cut when the width is variable, and the width can be changed stably. Therefore, it is preferable. As the iron-based metal, stainless steel or carbon steel may be used. However, when a material harder than the slide provided with the slit is used in relation to the material of the slide provided with the slit, wear occurs in the slit portion of the slide coater. For example, when the material of the slide 2 provided with the slit 3 is SUS304 stainless steel, SUS304 stainless steel is suitable as the material of the portion facing the slit 3 of the liquid film width adjusting device 4. Although carbon steel can be used, since it is slightly hard, there is concern about some wear, but carbon steel may be used as it is for a short time. The reason why these metals have good wettability with the paint is thought to be due to the anchor effect due to the high pore density of the material surface and the difference in surface tension between the metal and the paint.

  When acrylic plastic is used as the material for the liquid film width adjusting device, the end portion of the film does not break, but it is not preferable because the plastic may be altered or dissolved by the solvent contained in the paint. In addition, when Teflon (registered trademark) advantageous for reactivity is used, the wettability with the paint is poor, and the liquid film does not adhere to the liquid film width adjusting device at the end of the slit, and the liquid film of this part is generated. Unstable “film breakage at the end” occurs, which is not preferable.

  The gap between the slit 3 and the liquid film width adjusting device 4 needs to be adjusted to 100 μm or less at most. The reason for this is that if the gap is large, the coating material enters between them, which may hinder the movement of the liquid film width adjusting device. This adjustment of the gap can also be solved by using a liquid film width adjusting device made of an iron-based metal that can maintain accuracy in processing and is very good in rubbing with a slide provided with a slit.

  Next, the slide type coating apparatus and the coating method of the present invention that can make the thickness of the coating film, particularly the thickness of the coating film at both ends of the width, more uniform will be described.

  When coating is performed by a slide type coating apparatus using the liquid film width adjusting device of the present invention shown in FIGS. 1 (b), 2 (b) and 2 (c), the thickness of the coating becomes uneven in the width direction. There was a thing. In particular, there was a tendency that the thickness at the width end portion of the coating film was increased.

In the slide type coating apparatus of the present invention in which the liquid film width adjusting device is movable in the width direction of the slit, the width of the slit 3 and the width W ₀ of the header portion 5 for supplying the liquid to the slit are as shown in FIG. As shown, it has a width corresponding to the widest width of the liquid film. Then, by moving the parallel flat plate 10 or the wedge-shaped flat plate 9 as the liquid film width adjusting device 4, the width W of the slit 3 opened on the slide is adjusted. Match the width of the coating sometimes required. At this time, the liquid supplied to the header portion 5 flows to the full width (W ₀ ) of the header portion 5 as shown in FIG. Since the upper portion of the slit 3 near the end of the width W ₀ is closed with a liquid film width adjusting device such as a parallel plate 10, the supplied liquid is concentrated near the end of the opening of the slit 3 having the width W. Will be supplied. This has been found to be the cause of the tendency for the thickness at the width end of the coating to increase.

  In the present invention, as shown in FIGS. 3 and 4A, the end of the header portion 5 has a header end plug 25, and the header end plug 25 is movable in the width direction of the header portion 5. There is a coating film having a uniform thickness in the width direction by using a slide type coating device having a depth corresponding to the slit depth of the fitting portion in the slit of the liquid film width adjusting device 4. It was possible to form.

  In this case, the header part 5 penetrates both side surfaces of the slide type coating apparatus, and the header end plugs 25 are inserted from the through holes on both side surfaces. Both end portions of the header portion 5 are closed by the header end plug 25. The header end plug 25 can be moved in the width direction of the header section 5 by the moving device 26.

  The liquid film width adjusting instrument 4 and the parallel plate 10 move in the width direction of the slit 3 to adjust the width of the slit opening to the width W. At this time, as shown in FIGS. 3 (b) and 4 (a), there is a moving device 26 as a mechanism for mechanically moving the header end plug 25 in the lateral direction. It moves to the width direction of the header part 5, and the opening width of the header part 5 is similarly adjusted to the width W. As a result, the width is unified to W from the header portion 5 through the slit 3 to the slit opening on the slide 2, so that the outflow amount of the liquid is made uniform in the width direction, resulting in the thickness of the coating film. It is possible to make the thickness uniform.

  The moving device 26 for moving the header end plug 25 in the horizontal direction may be moved in the horizontal direction by adjusting the air pressure instead of mechanically. Specifically, an air cylinder is connected to the header end plug 25, and the position of the header end plug 25 is adjusted by the pressure of the air supplied to the air cylinder.

  In the above-mentioned present invention, the fitting portion in the slit (such as the parallel plate 10) of the liquid film width adjusting device 4 has a depth corresponding to the slit depth, so the liquid film width adjusting device 4 and the header end plug 25 A good flow path for obtaining a uniform discharge amount can be formed.

  In the present invention, air may be inserted from both ends of the slit and the header portion and the liquid film width may be adjusted by adjusting the air pressure instead of the header end plug and the liquid film width adjusting device. As shown in FIG. 5A, air supply portions 27 are provided at both ends of the slit 3 and the header portion 5. As shown in FIG. 5B, when air is inserted into the slit 3 and the header part 5 from the air supply part 27, the liquid exists only inside the gas-liquid boundary part 28, whereby the header part 5 Since the width of the liquid is unified to W through the slit 3 to the slit opening on the slide 2, the outflow amount of the liquid is made uniform in the width direction, and as a result, the thickness of the coating film is made uniform It becomes possible to do.

  Next, control of the paint discharge amount and the width movement speed when the liquid film width adjusting device is moved in the slit direction to change the width of the liquid film will be described. When the width of the liquid film is widened while keeping the paint at a constant flow rate, the filling of the paint is delayed and the paint does not adhere to the liquid film width adjusting device.

  In the present invention, the movement speed of the liquid film width adjusting device 4 and the discharge flow rate of the paint discharged from the slit 3 are interlocked so that the discharge per unit length while the liquid film width adjusting device 4 moves. By controlling so that the flow rate is constant, good control can be realized.

  In this case, if the supply amount of the paint is accelerated and the static pressure in the chamber is changed, the paint tends to overflow from the slit, and the paint adheres to the liquid film width adjusting device sooner. Therefore, it is preferable to control the change in the supply amount of the paint in synchronization with the movement of the liquid film width adjusting device.

  In addition, when the above adjustment is performed, the flow rate per unit width of the liquid film can be kept constant. Since it is becoming clear that the width of the liquid film away from the edge guide changes depending on the discharge flow rate per unit width, this prevents the change in the width of the liquid film due to the flow rate change per unit width. Can do.

  In addition, the moving speed of the liquid film width adjusting device 4 was examined.

  The limit of the moving speed of the liquid film width adjusting device 4 with the variable high-speed width is the limit of film formation due to end film breakage. In order to increase the width at high speed, the end film breakage means that if the liquid film width adjusting device is moved at high speed, the liquid film width adjusting device will not adhere to the liquid film and the liquid film will not spread sufficiently. This is a phenomenon in which the film is cut.

In the present invention, as described above, the shape and material of the liquid film width adjusting device 4 are selected, and further, the discharge flow rate at the time of changing the width is controlled, so that the upper limit of the moving speed of the liquid film width adjusting device due to the film forming limit. Can be increased to 50 mm / s. The lower limit of the moving speed was 5 mm / s. If it is 5 mm / s or less, it takes too much time to change the width, resulting in a disadvantage for the waste part of the paint and the yield of the steel plate. Therefore, the range of the moving speed is 5 mm / s to 50 mm / s. Note that the phenomenon of the end film being cut still has to do with the viscosity and wettability of the paint, so the moving speed needs to be adjusted according to the properties of the liquid film paint.
In the slide type coating apparatus of the present invention having a mechanism for moving the header end plug and the header end plug mechanically in the lateral direction at the end of the header section, the header end plug is mechanically moved in the lateral direction. The moving speed of the mechanism to be moved is preferably 5 mm / s to 50 mm / s.

  As described above, the liquid film width adjusting device has a moving speed of 50 mm / s or less, and the means for moving the liquid film width adjusting device is a means that can move at this speed and that can be installed on a slide. I need it. As an example, the screw motor 13 capable of high-speed rotation is used in FIG. 1, but an air cylinder, a stepping cylinder, or the like may be used.

  The length of the slit in the depth direction shown in FIG. 8 is one of the conditions related to stabilization. In the present invention, the length in the depth direction of the slit is suitably 15 mm to 100 mm. The minimum length is the minimum length at which the flow in the slit develops and stabilizes sufficiently in laminar flow when the static pressure changes. When the maximum value exceeds this value, the delay time cannot be ignored when the discharge flow rate changes due to a change in static pressure.

  By the way, when changing the width | variety of the multilayer liquid film layer 9, the following two types can be considered. One is a case where the widths of all the multilayer liquid film layers are made constant and these widths are changed at the same time, and the other is the configuration of the wide film 20 and the narrow film 21 as shown in FIG. When the width of the wide film 20 is made wider than the band 8 to be coated, and the paint of the wide film 20 wider than the band 8 to be painted is reused after collection, and only the width of the narrow film 21 is changed. It is. Furthermore, it is also possible to adopt a method in which the wide film 20 and the narrow film 21 are configured as described above, and the widths of both the wide film 20 and the narrow film 21 are changed.

  Ancillary equipment necessary for incorporating the slide type coating apparatus of the present invention into an actual painting line was examined below. In this case, the steel sheet was considered as the strip 8 to be coated. Of course, it is conceivable that a strip-like material other than the steel plate exhibits the same effect.

  As a slide type coating apparatus, a device having a wide film 20 and a narrow film 21 as shown in FIG. 8 is considered. 1) The width is larger than the width of the band-shaped object 8 moving the wide film 20 and the narrow film is narrow. A form in which the width of the film 21 is made smaller than the width of the band-like object 8 and only the paint of the wide film 20 is collected and reused; 2) the width of the band-like object 8 moving through the wide film 20 is made larger; The width of the narrow film 21 is also made larger than the width of the strip 8, and the case where only the paint of the wide film 20 is collected and reused was examined.

  First, the equipment and method for adjusting the position of the narrow film 21 and the steel plate position will be described.

  Steel plates with variable width are connected to steel plates of different widths in the pretreatment process in the painting line. At this time, the center line of each steel plate may shift. As described above, when the position of the narrow film is adjusted while the center line is shifted, a portion where the narrow film cannot be coated may be formed at the end of the steel sheet. Therefore, it is necessary to detect the width position of the steel plate and adjust the position of the narrow film based on this signal. Therefore, as shown in FIG. 6, an EPC (ELECTRIC POSITION CONTROL) is installed in front of the slide type coating device as the width position detecting device 14 for detecting the width position of the steel plate, and the steel plate width position is detected by this signal. The position of the narrow film 21 is adjusted by adjusting the stop position of the liquid film width adjusting instrument 4 based on the above. The EPC in this case has a slit-like light source and a detection device in which phototubes are arranged in the horizontal direction. The accuracy is about ± 0.2 mm. Other methods for detecting the edge of the steel sheet include a laser method and a vortex method.

  Although this method is exemplified as adjusting only the width of the narrow film, the signal of the end position of the steel plate detected by this EPC is the width of all the liquid films in the slide type coating apparatus having the same width of all the slits. Based on the above, the width of the liquid film may be changed.

  Next, the collection of the mixed paint will be described. When the narrow film 21 is larger than the width of the steel plate, as shown in FIG. 7A, a partition plate 16 is provided at a position corresponding to the outside of the narrow film 21 to correspond to the width of the narrow film. The partition plate 16 is moved so that the paint mixed with the narrow film and the wide film can be collected separately from the paint with the wide film. On the other hand, when the narrow film can always be smaller than the steel plate width, such a partition plate is not necessary. However, if there is a possibility that the narrow film will be larger than the steel sheet width when changing the width of the steel sheet, it is necessary to provide a partition plate as described above and move this partition plate according to the width of the narrow film. Become.

  Although the slide type coating apparatus of the present invention and the coating method using the same were mainly described with respect to the curtain coating method applied to the strip after the liquid film layer dropped from the slide to form the curtain, as an example, Of course, the slide bead method in which the curtain is applied to the belt-like object without being detached from the slide without generating a curtain is also applicable.

  Next, examples of the present invention will be described. In the steel plate coating line, the present invention was applied when applying a plurality of coatings on the surface of a steel plate. The running speed of the steel plate is 80 m / min.

  The liquid film slide type coating apparatus used in Example 1 will be described. The configuration of the slide type coating apparatus and the shape of the liquid film width adjusting device 4 are shown in FIG. SUS304 stainless steel was used as the material of the liquid film width adjusting device 4. The width of the liquid film width adjusting device 4 is 100 mm, and the surface in contact with the slide is 50 mm so that it can move laterally in the slit on the slide having a width of 0.5 mm and the gap can be adjusted. It has a protruding flat plate 11 having a height and a wedge shape. The wedge-shaped flat plate 11 is fitted into the slit 3. The liquid film width adjusting device 4 can be moved by a screw 13 connected to a motor in the width direction. With this mechanism, the liquid film width adjusting device 4 can move in the lateral direction at a moving speed of 5 mm / s to 50 mm / s. In order to adjust the gap between the slide 3 and the liquid film width adjusting device 4, an air cylinder 12 for pressure adjustment is provided on the liquid film width adjusting device. The air pressure is adjusted when the slide-type coating device is actually filled with paint.

  The gap between the slit portion that appeared on the slide side surface of the slide type coating apparatus and the wedge-shaped flat plate 11 of the liquid film width adjusting device was also sealed with synthetic rubber. The paint that slightly leaks during the movement of the liquid film width adjusting device 4 was collected by providing a dish under the end of the slide.

(Example 1-1)
In this embodiment, when the coating is performed using the above-described apparatus, the width of the wide coating film 20 is wider than the width of the steel plate and the width of the narrow width film 21 is narrower than the width of the steel plate. As one form of the method, the case where the plate width is changed from 1000 mm to 900 mm is shown. No steel plate width position detection device is provided.

  When the steel plate width was 1000 mm, the width of the narrow film was 985 mm, and when the steel plate width was 900 mm, the width of the narrow film was 885 mm. The width of the wide film was constant at 1100 mm.

  From 10 m before the width of the steel plate changed, the liquid film width adjusting device 4 on both sides of the slit on the slide was narrowed at a moving speed of 10 mm / s. The shutter 18 shown in FIG. 7B is placed between the curtain and the collection tank 15 30 seconds before the liquid film width adjusting device is moved, and when the width is changed, the mixed paint of the narrow film and the wide film paint is discarded. did.

  When the width of the steel plate is changed and the movement of the liquid film width adjusting device 4 is completed, the width of the narrow film 21 is 885 mm. When changing the steel plate width, the width of the narrow film 21 can be corrected without stopping the running of the steel plate. In addition, the amount of paint mixed with the narrow film and wide film paint discarded when the steel plate width was changed was 15% of the total paint applied per unit time.

(Example 1-2)
In addition to Example 1-1, EPC was used as the steel sheet width position detection device 14. Since the width position detecting device 14 is used, the difference between the steel plate width and the width of the narrow film can be reduced to 10 mm. When the plate width is changed from 1000 mm to 900 mm, the end position of the steel plate is detected by EPC, and after changing the width, the liquid film width adjusting device is moved at a moving speed of 10 mm / s, and the width of the narrow film is reduced. It was corrected from 990 mm to 890 mm.

  As in Example 1-1, the width can be changed without stopping the travel of the steel sheet, and at the same time, the amount of paint mixed with the narrow film and wide film paint discarded when the steel sheet width is changed is determined in unit time. To 5% of the total coating applied. Further, as an effect of providing the steel plate width position detecting device 14, the difference between the steel plate width and the width of the narrow film during traveling of the steel sheet other than when changing the width can be reduced. It is possible to improve the control accuracy of the position of the partition plate 16 that prevents mixing, and by setting the partition plate 16 at a limit position that prevents mixing, the amount of paint mixture other than at the time of width change is The effect of being able to reduce to 1/3 was born.

(Example 1-3)
In this example, the same apparatus as that of Example 1-2 is used, and a case where the plate width is changed from 900 mm to 1000 mm is shown as one form of the operation method at the time of changing the width. The width of the narrow film is changed from 890 mm to 990 mm.

  Immediately after the width of the steel sheet changed, the liquid film width adjusting device 4 was widened at a moving speed of 10 mm / s. The shutter 18 shown in FIG. 7B was set at a position where the shutter 18 was under the steel plate 5 seconds before the liquid film width adjusting device 4 was moved and was not in contact with the steel plate even if there was a control trouble.

  During the width change, a region where the narrow film 21 is not applied to both ends of the 1000 mm wide steel plate is generated. In this region, the width trim of the steel plate is increased. Although steel plate yield loss due to the width trim occurred, the width could be changed without stopping the travel of the steel plate.

(Example 1-4)
In this embodiment, the width of the wide film is wider than the width of the steel sheet, and at the same time, as one form of the operation method when changing the width when the width of the narrow film is wider than the width of the steel sheet, the width of the steel sheet is changed from 900 mm to 1000 mm. Show the case.

  In addition to the equipment of Example 1-1, a partition plate 16 is provided in the collection tank 15. The position of the partition plate 16 is movable in the width direction of the slit 3. A stepping cylinder 17 is used for the movement. The width of the narrow film 21 was changed from 930 mm to 1030 mm, and the width of the narrow film 21 was changed as the width of the steel plate plus 30 mm.

  The liquid film width adjusting device 4 was spread at a moving speed of 20 mm / s from 5 seconds before the width of the steel plate changed. At the same time, the position of the partition plate 16 of the collection tank was moved in conjunction with the movement of the liquid film width adjusting device 4.

  When changing the steel plate width, the width of the narrow film can be corrected without stopping the running of the steel plate. Further, even when the width of the steel sheet was changed, the layer having only the wide film could be recovered independently and reused.

(Example 1-5)
In addition to Example 1-4, EPC was used as the steel sheet width position detection device 14. Since the width position detection device 14 was used, the difference between the steel plate width and the width of the narrow film could be reduced to 10 mm. As a result, it was possible to reduce the amount of paint collected and discarded by mixing the wide film and the narrow film.

  The liquid film slide type coating apparatus used in Example 2 will be described. The configuration of the slide type coating apparatus and the shapes of the liquid film width adjusting device 4 and the header end plug 25 are shown in FIG.

  The header portion 5 penetrates both side surfaces of the slide type coating apparatus, and the header end plugs 25 are inserted from both side surfaces. The header end plug 25 can be moved in the header width direction by the moving device 26. Liquid is supplied to the header portion 5 from the vicinity of the width center of the header portion 5.

  The slit 3 has an opening width of 0.5 mm, and the length of the slit 3 from the header 5 to the slide 2 is 60 mm. SUS304 stainless steel was used as the material of the liquid film width adjusting device 4. The width of the liquid film width adjusting device 4 is 100 mm, and the fitting portion in the slit of the liquid film width adjusting device 4 forms a parallel plate 10, and the length in the depth direction of the parallel plate 10 is the depth direction of the slit. Equal to length. The liquid film width adjusting device 4 can be moved by a screw 13 connected to a motor in the width direction. With this mechanism, the liquid film width adjusting device 4 can move in the lateral direction at a moving speed of 5 mm / s to 50 mm / s.

  The gaps between the slit portions appearing on both sides of the slide type coating apparatus and the parallel plate 10 of the liquid film width adjusting device, and the gap between the header part 5 and the header end plug 25 were sealed with synthetic rubber. The paint that slightly leaks during the movement of the liquid film width adjusting device 4 was collected by providing a dish under the end of the slide.

  As shown in FIG. 4A, when the width of the header portion surrounded by the header end plugs 25 arranged on both sides of the header portion is the same as the width W of the slit 3, the film thickness distribution in the width direction Was almost uniform, and the variation was 2% or less. On the other hand, when the width of the header portion is 200 mm (100 mm on one side) larger than the width W of the slit 3 as shown in FIG. 4B, the film thickness of this portion is 30 mm from the end of the slit 3 opening. The film thickness increased by 50% compared to the film thickness at the center in the direction. The film thickness here may be either the film thickness of the liquid curtain that has flowed out of the slide coater or the film thickness after drying.

  In this example, the liquid film width adjusting device and the header end plug were mechanically moved, but the liquid film width adjusting device and the header end plug were manually moved without using a machine for moving them. Even if it is moved to make the width of the slit 3 and the width of the header portion the same, the same effect of uniforming the film thickness in the width direction can be obtained.

  The same effect can be obtained by inserting air from the left and right instead of the liquid film width adjusting device and the header end plug and changing the liquid film width by adjusting the air pressure.

It is a figure which shows the slide type coating apparatus of this invention, (a) is the schematic of a slide, (b) is a fragmentary sectional view which shows the relationship between a liquid film width adjusting device and a slit. It is a figure which shows the slide type coating apparatus of this invention, (a) is the schematic of a slide, (b) (c) is a fragmentary sectional view which shows the relationship between a liquid film width adjusting device and a slit. It is a figure which shows the slide type coating device of this invention which has a header end plug, (a) is a schematic diagram of a slide, (b) is a BB arrow sectional drawing, (c) is an AA arrow sectional drawing. FIG. It is a figure which shows the flow condition of the liquid which flows in a header part and a slit, (a) is a BB arrow directional view of FIG. 3, (b) is DD arrow sectional drawing, (c) is CC. It is arrow sectional drawing. It is a figure which shows the slide type coating apparatus of this invention which has an air supply part, (a) is schematic of a slide, (b) is sectional drawing which shows the cross section of a slide. It is a figure which shows the slide type coating device of this invention which has a width position detection apparatus. It is a figure which shows the slide type coating apparatus of this invention which has a coating material collection | recovery apparatus. It is a figure which shows a slide type coating apparatus, (a) is a front view, (b) is AA arrow sectional drawing.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Slide type coating apparatus 2 Slide 3 Slit 4 Liquid film width adjustment instrument 5 Header part (paint reservoir)
6 Curtain guide 7 Edge guide 8 Strip 9 Liquid film layer 10 Parallel plate 11 Wedge plate 12 Air cylinder 13 Screw motor 14 Width position detection device 15 Collection tank 16 Partition plate 17 Stepping cylinder 18 Shutter 19 Taper slit 20 Wide layer 21 Narrow layer 22 Band-like object traveling direction 25 Header end plug 26 Moving device 27 Air supply unit 28 Gas-liquid boundary part

Claims (10)

  In a slide type coating apparatus for forming a liquid film layer composed of a plurality of liquid films by discharging liquid from a plurality of slits provided on a slide and applying the liquid film layer onto a moving belt-like object, one layer Or a device for sealing the end of a slit on a slide provided for the purpose of changing the width of a plurality of layers of liquid films (hereinafter referred to as “liquid film width adjusting device”), and this liquid film The width adjusting device can be moved in the width direction of the slit, and a part of the shape of the liquid film width adjusting device is a wedge-shaped flat plate that fits into the slit. And a mechanism for adjusting the distance between the slit on the slide and the wedge-shaped flat plate provided on the liquid film width adjusting device fitted thereto. .   2. The slide type coating apparatus according to claim 1, wherein the portion of the liquid film width adjusting device facing the slit is made of a metal containing iron.   The slide type coating apparatus has a header portion for supplying liquid to the slit, and has an end plug at the end of the header portion, and the end plug of the header is movable in the width direction of the header portion. The slide coating apparatus according to claim 1 or 2, wherein the in-slit fitting portion of the membrane width adjusting device has a depth corresponding to the slit depth.   4. The slide type coating apparatus according to claim 3, further comprising a mechanism for moving the header end plug in a lateral direction mechanically or by adjusting air pressure.   It has one or both of a mechanism that mechanically moves the liquid film width adjusting device and a mechanism that mechanically moves the header end plug in the horizontal direction, and the moving speed is 5 mm / s or more and 50 mm / s or less. The slide type coating apparatus according to any one of claims 1 to 4, wherein   A width position detecting device for detecting the width position of the band is provided upstream of the moving band, and the stop position of the liquid film width adjusting device is adjusted based on the width position of the band detected by the width position detecting device. The slide type coating apparatus according to any one of claims 1 to 5, wherein   2. A recovery tank having a partition plate movable in the width direction of the slit at a lower portion of the slide, and the position of the partition plate can be adjusted based on the position of the liquid film width adjusting device. The slide type coating apparatus according to any one of claims 5 to 5.   A coating method using the slide type coating apparatus according to any one of claims 1 to 7, wherein the moving speed of the liquid film width adjusting device and the discharge flow rate of the paint discharged from the slit are interlocked, A coating method using a slide type coating apparatus, characterized in that the discharge flow rate per unit length is controlled to be constant while the liquid film width adjusting device moves.   A coating method using the slide type coating apparatus according to any one of claims 1 to 7, wherein the slide type coating apparatus is installed in a coating line, and a width position of a steel plate is detected upstream of the coating line. A coating method using a slide type coating apparatus, characterized in that a stop position of a liquid film width adjusting device in the slide type coating apparatus is adjusted based on the detection signal.   A coating method using the slide type coating apparatus according to any one of claims 1 to 7, wherein a liquid film layer is formed of a plurality of liquid films by discharging liquid from a plurality of slits provided on the slide. When forming the film, the width of one or more liquid films is wider than the width of the other liquid film to form a liquid film layer, and this liquid film layer is applied onto the moving strip. A collection tank with a partition plate movable in the width direction is provided at the bottom of the slide type coating device, and the position of the partition plate is adjusted based on the position of the liquid film width adjusting device in the slide type coating device. Or the coating method using the slide type coating device characterized by separating and collecting a plurality of liquid films.

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