JP5824887B2 - COATING APPARATUS AND COATING METHOD - Google Patents

Description

  The present invention relates to a coating apparatus for a coating object and a coating method for the coating object.

  Various coating methods such as electrodeposition coating, electrostatic coating, spray coating, fluidized immersion coating, and the like are known as methods for coating an object to be coated.

  Patent Document 1 discloses that an object to be coated is buried in a paint medium layer formed by a medium (paint medium) filled in a paint filling tank and having a powder paint adhering to the surface, and the paint medium layer is stirred and buried. Disclosed is a fluidized dip coating method for coating a workpiece by maintaining the state for a predetermined time. The coating medium in the tank collides with the object to be coated by stirring. By repeatedly performing the collision, the powder coating material adhering to the coating medium is applied (transferred) to the object to be coated.

  Patent Document 2 creates a circulating flow of a coating medium to which a powder coating is adhered, and applies the powder coating adhered to the coating medium to the coating by contacting the coating with the generated circulating flow while rotating. Disclosed is a coating method.

  Similarly to Patent Document 2, Patent Document 3 creates a circulating flow of the coating medium to which the powder coating is adhered, and the powder coating adhered to the coating medium is brought into contact with the created circulating flow while rotating the object to be coated. Disclosed is a coating method for applying to an object. According to Patent Document 3, a color image of a paint medium is picked up by a CCD camera, and the circulating flow rate of the paint medium is controlled based on the picked up color image.

Japanese Patent No. 3482225 (FIGS. 8, 9, and 10) JP 2007-136331 A (FIGS. 12, 13, and 14) JP 2007-139561 A (FIG. 6)

(Problems to be solved by the invention)
The paint medium filled in the paint filling tank shown in Patent Document 1 is made of ceramics, for example, and has a large specific gravity of about 2.5 to 6. A load (input load) necessary for burying an object to be coated in a paint medium layer composed of a paint medium having a large specific gravity is large. In addition, a load (pull-up load) required when pulling up an object buried in the paint medium layer is large. When the input load or the lifting load is large, the apparatus configuration becomes large and the apparatus cost increases. In addition, there is a possibility that a workpiece or a jig for attaching the workpiece is deformed when the workpiece is charged or pulled up.

  In this case, the input load can be reduced by burying the article to be coated in the paint medium layer while vibrating the paint filling tank filled with the paint medium. However, the input load necessary for burying the whole object to be coated in the coating medium layer is still large. In addition, a large driving energy is required to vibrate the entire paint filling tank. Therefore, the manufacturing cost is increased.

  If the object to be coated is first put into the paint filling tank, and then the paint medium to which the powder paint is adhered is filled into the paint filling tank, the load of the object to be applied can be reduced. However, in this case, every time an object is coated, an operation of filling the coating material medium into the coating material filling tank occurs, so that the number of work steps increases and the productivity deteriorates.

  In addition, according to the coating methods described in Patent Documents 2 and 3, a circulating flow of the coating medium to which the powder coating is adhered is created by a belt conveyor or gravity drop, but the coating medium in the circulating flow is not sufficiently stirred. . For example, when the coating medium is circulated by an endless belt or the like, the coating medium is transported in a state where the coating medium is statically placed on the endless belt, and thus the coating medium is not stirred. Therefore, when the object to be coated is brought into contact with the circulating flow of the coating medium that is not sufficiently stirred, the coating film thickness becomes non-uniform, and the coating quality is adversely affected.

  SUMMARY OF THE INVENTION An object of the present invention is to provide a coating apparatus and a coating method for a coating that can realize coating without reducing the input load of the coating without deteriorating the productivity and without adversely affecting the coating quality. And

(Means for solving the problem)
In the present invention, a cylindrical space extending in the vertical direction is formed inside, a processing tank having an upper surface and a lower surface opened, and a cylindrical space extending in the horizontal direction is formed inside, and is disposed below the processing tank. And a first cylinder having an opening formed at a position facing an opening portion on the lower surface of the processing tank, a first screw coaxially disposed in the first cylinder, and the first screw connected to the first screw. A first transfer motor having a first drive motor for rotating the first screw; and a second cylinder having a cylindrical space extending in the vertical direction formed therein and connected to an end of the first cylinder; , A second transfer unit having a second screw coaxially arranged in the second cylinder, and a second drive motor connected to the second screw and rotating the second screw, and one end side of the second screw A transfer passage having an opening at a portion located above the end portion of the first cylinder connected to the end of the first cylinder and the other end opening to the treatment tank side, and an opening portion on the upper surface of the treatment tank. An actuator that drives the article to be moved in the vertical direction so that the paint descends and enters the treatment tank, and the powder paint adhered to the surface of the paint medium filled in the treatment tank A coating apparatus that causes the powder coating material to adhere to the object to be coated by contacting the object to be coated, wherein a downward flow in which the coating medium flows downward from above is formed in the processing tank. The actuator provides a coating apparatus for driving the object to be coated so that the object to be coated descends from the opening portion on the upper surface of the processing tank and the object to be coated is introduced into the descending flow . The

  The present invention is also a coating method for coating an object to be coated using the above-described coating apparatus of the present invention, wherein a coating medium having a powder coating adhered to the surface is supplied into the treatment tank and the first is used. By driving the drive motor and the second drive motor to rotate the first screw and the second screw, a downward flow in which the coating medium flows downward from above in the processing tank is continuously formed. As described above, the step of forming a circulating flow of the coating medium and the actuator are driven to lower the article to be coated from the opening on the upper surface of the treatment tank and enter the treatment tank. In the downward flow and maintaining the state in which the object is being injected in the downward flow for a predetermined time, the coating medium is brought into contact with the object to be coated. Powder coating on coating And a step of attaching, to provide a coating method of coating objects. In this case, it is preferable to further include a step of vibrating the treatment tank in the horizontal direction. Furthermore, it is a process performed after the process of attaching a powder coating material to a to-be-coated object, It is good to further include the process of driving the said actuator and pulling up to-be-coated object from the said downward flow.

  According to the present invention, the coating medium supplied into the processing tank flows from the upper side to the lower side of the processing tank by gravity, and is introduced into the first cylinder from the opening portion of the lower surface of the processing tank through the opening of the first cylinder. . The coating medium put into the first cylinder is stirred and moved by the rotation of the first screw and transferred from the end of the first cylinder to the second cylinder. The coating medium transferred to the second cylinder is stirred and moved upward by the rotation of the second screw, and further transferred from the second cylinder to the transfer passage. And it discharges from the other end opening of the transfer passage. The coating medium discharged from the other end opening of the transfer passage is supplied again to the treatment tank. And it flows from the upper part to the lower part in the treatment tank. In this way, a circulating flow of the coating medium is created so that a downward flow of the coating medium flowing from the upper side to the lower side in the processing tank is continuously formed.

  Further, when the actuator is driven, the object to be coated is lowered from the opening on the upper surface of the processing tank and enters the processing tank. Then, the object to be coated is thrown into the processing tank while the coating medium is descending. The coating medium comes into contact with the coating object by introducing the coating object during the downward flow of the coating medium. When the coating medium is repeatedly contacted with the object, the powder paint adheres to the object. As a result, the article to be coated is painted.

  Since the coating medium flows in the treatment tank so as to form a downward flow, the filling density in the downward flow is smaller than the filling density when the coating medium is accumulated in the treatment tank. In this way, the object to be coated is thrown into the downward flow of the coating medium having a small filling density, so that the loading load necessary for the charging is reduced. In addition, since the input direction of the object to be coated and the flow direction of the coating medium coincide with each other, the input load is further reduced. Further, if the treatment tank is vibrated in the horizontal direction by the vibration means to promote the flow of the coating medium in the treatment tank, the input load can be further reduced.

  Further, the coating medium is sufficiently stirred in the first cylinder and the second cylinder by the rotation of the first screw and the second screw. Therefore, when the uniformly stirred coating medium comes into contact with the object to be coated in the treatment tank, the powder paint can be uniformly adhered to the surface of the object to be coated. Therefore, the coating quality is improved.

  In the present invention, “the other end side of the transfer passage is open to the processing tank side” means that the other end side of the transfer passage is connected to the processing tank and opens directly to the processing tank (for example, on the side surface on the upper side of the processing tank). It is an expression including a mode in which the transfer path is separated from the processing tank and the other end side opens toward the processing tank (for example, the upper surface of the processing tank). That is, the opening state with respect to the processing tank on the other end side of the transfer passage is that the coating medium discharged from the opening on the other end side of the transfer passage is supplied to the processing tank, and the supplied coating medium forms a downward flow in the processing tank. Any mode may be used as long as it is possible. Moreover, the opening part of the 1st cylinder may be directly connected by the communication pipe etc. to the opening part of the lower surface of a processing tank, and may be arrange | positioned facing the opening part of the lower surface of a processing tank. In this case, a hopper may be attached around the opening of the first cylinder.

It is a front view showing schematic structure of the coating device concerning this embodiment. It is sectional drawing showing the internal structure of a processing tank, a 1st transfer part, and a 2nd transfer part. It is a figure which shows a circulating flow formation process. It is a figure which shows an injection | throwing-in process and a painting process. It is a figure which shows a raising process.

  Hereinafter, embodiments of the present invention will be described. FIG. 1 is a front view illustrating a schematic configuration of a coating apparatus according to the present embodiment. The coating apparatus 1 shown in FIG. 1 includes a treatment tank 10, a first transfer unit 20, a second transfer unit 30, a transfer passage 40, a vibration exciter 50, a gantry 60, and an air cylinder 70.

  The processing tank 10 has a substantially cylindrical shape. A first transfer unit 20 is disposed below the processing tank 10. In the drawing of the first transfer unit 20, the second transfer unit 30 is disposed on the right side.

  FIG. 2 is a cross-sectional view illustrating the internal structure of the processing tank 10, the first transfer unit 20, and the second transfer unit 30. As shown in FIG. 2, the processing tank 10 is configured in a substantially cylindrical shape, and a cylindrical space extending in the vertical direction is formed therein. The upper surface and the lower surface of the treatment tank 10 are opened. The upper part of the treatment tank 10 is expanded in diameter.

  The first transfer unit 20 includes a first cylinder 21, a first screw 22, and a first drive motor 23. The first cylinder 21 has a cylindrical shape and is disposed below the processing tank 10. A cylindrical space extending in the horizontal direction in the drawing is formed inside the first cylinder 21. The first screw 22 is coaxially arranged inside the first cylinder 21. The first screw 22 includes a shaft portion 221 and a plurality of wing portions 222. The shaft portion 221 is disposed over the longitudinal direction of the first cylinder 21. A plurality of wing portions 222 are provided at equal intervals along the longitudinal direction of the shaft portion 221.

  An opening 21a is formed in a portion of the side wall of the first cylinder 21 facing upward in FIG. The opening 21 a is formed at a position facing the opening portion on the lower surface of the processing tank 10. A hopper 21b is attached around the opening 21a. As shown in the drawing, the hopper 21b is formed in a funnel shape so that its diameter increases toward the upper side. The upper surface opening of the hopper 21b and the lower surface opening of the treatment tank 10 face each other, and as shown in FIG. 1, the bellows-shaped rubber tube 80 is formed between the treatment tank 10 and the hopper 21b so as to cover both openings from the outside. It is provided between. The upper end side of the rubber tube 80 is attached to the lower end portion of the processing tank 10, and the lower end side is attached to the upper end side of the hopper 211b. The rubber tube 80 absorbs vibration generated in the horizontal direction in the drawing of the processing tank 10 with respect to the hopper 21b.

  A first drive motor 23 is disposed at the left end of the first cylinder 21 in FIG. The output shaft of the first drive motor 23 is coaxially connected to the left end of the shaft portion 221. When the first drive motor 23 is driven, the first screw 22 rotates in the first cylinder 21. As the first screw 22 rotates, the coating beads supplied into the first cylinder 21 move in the first cylinder 21 as will be described later. In this case, the drive direction (rotation direction) of the first drive motor 23 is determined so that the paint beads move in the first cylinder 21 to the right in the drawing by the rotation of the first screw 22.

  As shown in FIG. 2, the second transfer unit 30 includes a second cylinder 31, a second screw 32, and a second drive motor 33. The second cylinder 31 has a cylindrical shape and is disposed in parallel with the processing tank 10. A cylindrical space extending in the vertical direction in the figure is formed inside the second cylinder 31. The second screw 32 is coaxially arranged inside the second cylinder 31. The second screw 32 includes a shaft portion 321 and a plurality of wing portions 322. The shaft portion 321 is disposed over the longitudinal direction of the second cylinder 31. A plurality of wing portions 322 are provided at equal intervals along the longitudinal direction of the shaft portion 321.

  As shown in FIG. 2, the second cylinder 31 is connected to the right end portion of the first cylinder 21 at a lower portion thereof. Therefore, the internal space of the second cylinder 31 communicates with the internal space of the first cylinder 21 at the lower portion thereof.

  A second drive motor 33 is disposed at the upper end of the second cylinder 31 in the figure. The output shaft of the second drive motor 33 is coaxially connected to the upper end of the shaft portion 321 in the figure. When the second drive motor 33 is driven, the second screw 32 rotates in the second cylinder 31. As the second screw 32 rotates, the coating beads transferred from the first cylinder 31 move in the second cylinder 31 as described later. In this case, the drive direction (rotation direction) of the second drive motor 33 is determined so that the paint beads move upward in the second cylinder 31 by the rotation of the second screw 32.

  The transfer passage 40 is a cylindrical member, and communicates with the second cylinder 31 at one end and opens to the outside at the other end. The transfer passage 40 is a portion located above the lower portion of the second cylinder 31 to which the end of the first cylinder 21 is connected, that is, a portion higher than the portion to which the end of the first cylinder 21 is connected. Connected to In addition, the transfer passage 40 is inclined so that the height on one end side communicating with the second cylinder 31 is higher than the height of the other end opening 41. Therefore, when paint beads (described later) are transferred from the second cylinder 31 to the transfer passage 40, the paint beads slide down the transfer passage 40 from one end side to the other end side by gravity, and from the other end opening 41. Discharged. As shown in FIG. 2, the other end opening 41 opens to the processing tank 10. That is, the other end side of the transfer passage 40 is open to the processing tank 10 side. In the present embodiment, the height position on the other end side of the transfer passage 40 is higher than the upper surface opening of the processing tank 10, and therefore the other end side of the transfer passage 40 opens to the upper surface opening of the processing tank 10. .

  As shown in FIG. 1, the vibration device 50 includes a motor mounting table 51, a vibration motor 52, a disk 53, a rod 54, a mounting plate 55, a vibration absorbing rubber 56, and an LM guide 57. Is provided. A disc 53 is coaxially connected to the output shaft of the vibration motor 52 mounted on the motor mounting table 51. A pin 53a is attached to the eccentric portion of the disc 53, and one end of a rod 54 is rotatably fixed to the pin 53a. The other end of the rod 54 is rotatably fixed to the mounting plate 55. The mounting plate 55 is fixed to the side periphery of the processing tank 10. At least a part of the lower surface of the mounting plate 55 is fitted into the LM guide 57. The LM guide 57 allows the mounting plate 55 to move in the horizontal direction (left-right direction in FIG. 1). The LM guide 57 is fixed on a gantry 60 fixed on the base plate BP. A vibration absorbing rubber 56 is attached to the side periphery of the processing tank 10. In addition, a through hole is formed in the gantry 60 to such an extent that the treatment tank 10 can pass and vibration of the treatment tank 10 in the horizontal direction can be allowed.

  The air cylinder 70 includes a cylinder body 71 and a cylinder rod 72, and is disposed facing the upper surface of the processing tank 10 so that the cylinder rod 72 enters the processing tank 10 from the upper surface when the cylinder rod 72 extends. . The tip shape of the cylinder rod 72 is devised so that the workpiece W can be fixed to the tip of the cylinder rod 72.

  A method for coating an object to be coated using the coating apparatus 1 having such a configuration will be described below for each process.

(Preparation process)
First, the workpiece W is attached to the cylinder rod 72 of the air cylinder 70. In the present embodiment, the workpiece W is a long object such as a vehicle seat rail. And the to-be-coated article W is fixed to the cylinder rod 72 so that the longitudinal direction is along the up-down direction above the processing tank 10. In addition, it is good to make an adhesive adhere to the surface of the to-be-coated object W fixed to the cylinder rod 72 beforehand.

(Circulating flow forming process)
By driving the first drive motor 23 and the second drive motor 33, the first screw 22 and the second screw 32 are rotated. In addition, a large amount of paint beads is supplied into the first cylinder 21 from the upper surface opening of the processing tank 10. The paint bead is a bead having a powder paint to be coated on the article W to be coated. This paint bead corresponds to the paint medium of the present invention. In this embodiment, the beads are spherical and have a diameter of about 0.5 mm. The material of the beads is ceramics.

  The coating beads supplied into the processing tank 10 flow from the upper side to the lower side in the processing tank 10 and are supplied from the lower surface opening of the processing tank 10 into the first cylinder 21 via the hopper 21b. The paint beads supplied into the first cylinder 21 are agitated by the rotation of the first screw 22. Further, the coating beads in the first cylinder 21 move to the right in FIG. 2 in the first cylinder 21 by the rotation of the first screw 22. Then, it is transferred from the right end of the first cylinder 21 to the lower part of the second cylinder 31.

  The paint beads transferred to the second cylinder 31 are agitated by the rotation of the second screw 32. Further, the coating beads in the second cylinder 31 move upward in the second cylinder 31 in FIG. 2 by the rotation of the second screw 32. The paint beads that have moved to above the second cylinder 31 are transferred into a transfer passage 40 that is open at the top of the second cylinder 31.

  The paint beads transferred from the second cylinder 31 into the transfer passage 40 slide down in the transfer passage 40 due to gravity and are discharged to the outside from the other end opening 41. Since the other end opening 41 faces the upper surface opening of the processing tank 10 as described above, the coating beads discharged from the other end opening 41 are supplied into the processing tank 10 from the upper surface opening.

  The coating beads supplied into the processing tank 10 flow from the upper side to the lower side in the processing tank 10 by weight. And it discharges | emits from the lower surface of the processing tank 10. FIG. The discharged paint beads are collected in the hopper 21b and supplied again into the first cylinder 21 from the hopper 21b. In this way, a circulating flow of paint beads that flows in order through the first cylinder 21 -the second cylinder 31 -the transfer passage 40 -the treatment tank 10 is formed. The state of this circulating flow is shown in FIG.

  As shown in FIG. 3, a circulation flow is formed so that a downward flow of coating beads flowing in the processing tank 10 from the upper side to the lower side is continuously formed. In addition, the coating beads introduced into the processing tank 10 from the transfer passage 40 are not dropped and discharged from the lower surface of the processing tank 10 as they are, but are temporarily filled in the processing tank 10 and filled. Are sequentially discharged from the lower surface of the processing tank 10, and the circulation speed of the paint beads is adjusted so that an amount of the paint beads equal to the discharged amount is supplemented from the transfer passage 40. That is, the circulation speed of the paint beads is adjusted so that a constant amount of paint beads is always filled in the treatment tank 10 and the paint beads continuously flow downward in the treatment tank 10. In the present embodiment, the velocity of the downward flow of the paint beads in the treatment tank 10 is 150 mm / sec. The rotational speeds of the first screw 22 and the second screw 32 (the first drive motor 23 and the first drive motor 23 and the second screw 32) are such that this speed is about 60 kg / min. The rotational speed of the second drive motor 33 is adjusted.

(Excitation process)
Further, the vibration motor 52 is driven. The disk 53 is rotated by the drive of the vibration motor 52, and the rod 54 attached to the eccentric position of the disk 53 swings. As the rod 54 swings, the mounting plate 55 and the processing tank 10 fixed to the mounting plate 55 vibrate in the left-right direction (horizontal direction) in FIG. In addition, since the lower part of the processing tank 10 and the hopper 21b are connected by the rubber tube 80 and the vibration of the processing tank 10 is absorbed by the rubber tube 80, even if the processing tank 10 vibrates in the horizontal direction, the paint beads Is recovered in the hopper 21b without spilling outside from the lower surface opening of the processing tank 10. By vibrating the processing tank 10, the paint beads temporarily filled in the processing tank 10 are vibrated. Thereby, the flow of the paint beads in the treatment tank 10 is promoted, and a downward flow of paint beads without any stagnation in the treatment tank 10 is continuously formed.

(Input process)
Next, the air cylinder 70 is driven to extend the cylinder rod 72. As a result, the workpiece W fixed to the cylinder rod 72 descends and enters the treatment tank 10 from the upper surface side of the treatment tank 10. As described above, in the treatment tank 10, a downward flow of the coating beads temporarily filled in the treatment tank 10 is formed. An object to be coated W is introduced during the downward flow of the paint beads. FIG. 4 shows a state in which the workpiece W is thrown into the downflow in the treatment tank 10.

(Painting process)
The state (the state shown in FIG. 4) in which the workpiece W is thrown into the processing tank 10 while the coating beads are descending is maintained for a predetermined time (for example, 5 seconds). At this time, when the coating beads flowing in the treatment tank 10 come into contact with the workpiece W, the powder coating adhered to the coating beads adheres to the coating W. In the present embodiment, since the paint beads moving in the first cylinder 21 and the second cylinder 31 are agitated by the rotation of the first screw 22 and the second screw 32, the paint beads in contact with the article W to be coated are stirred. The amount of powder paint adhering to the surface is equalized. For this reason, a powder coating material adheres uniformly on the surface of the article W to be coated.

(Pulling process)
After maintaining the state shown in FIG. 4 for a predetermined time, the air cylinder 70 is driven and the cylinder rod 72 is contracted. As a result, the workpiece W is pulled upward from the downward flow of the coating beads flowing in the treatment tank 10. The powder coating is uniformly attached to the surface of the object W that has been pulled up. FIG. 5 shows a state where the workpiece W is pulled up.

  Thereafter, the workpiece W fixed to the cylinder rod 72 of the air cylinder 70 is removed, and the powder paint adhered to the surface is baked. Thereby, the coating to the workpiece W is completed.

  As described above, the coating apparatus 1 according to the present embodiment includes a treatment tank 10 in which a cylindrical space extending in the vertical direction is formed inside, and an upper surface and a lower surface are opened, and a cylindrical space extending in the horizontal direction is provided inside. And a first cylinder 21 disposed below the processing tank 10 and having an opening 21a formed at a position facing the opening portion of the lower surface of the processing tank 10, and a first cylinder 21 disposed coaxially within the first cylinder 21. A first transfer part 20 having a first screw 22 and a first drive motor 23 connected to the first screw 22 and rotating the first screw 22, and a cylindrical space extending in the vertical direction are formed inside and first A second cylinder 31 connected to an end of one cylinder 21; a second screw 32 disposed coaxially in the second cylinder 31; and a second screw 32 connected to the second screw 32 to rotate. The second transfer part 30 having the two drive motors 33 and one end side of the second cylinder 31 open to a part located above the part to which the end part of the first cylinder 21 is connected and the other end opening 41 has The workpiece W is driven in the vertical direction so that the workpiece W descends from the transfer passage 40 opened toward the upper surface of the processing tank 10 and the opening portion of the upper surface of the processing tank 10 and enters the processing tank 10. An air cylinder 70 to be operated.

  Moreover, the coating method of this embodiment which coats the workpiece W using the coating apparatus 1 supplies the coating beads having the powder coating adhered to the surface thereof into the treatment tank 10 and the first drive motor 23 and the second driving motor 23. The drive motor 33 is driven to rotate the first screw 22 and the second screw 32 so that the processing tank 10 is always temporarily filled with a certain amount of coating beads and the filled coating beads are opened on the lower surface of the processing tank 10. A circulation flow forming step for forming a circulation flow of the paint beads so that a downward flow of the paint beads flowing from the upper side to the lower side in the processing tank 10 is continuously formed by discharging from the portion in order, and the air cylinder 70. And a charging step for dropping the coating object W into the processing tank 10 by lowering the coating object W from the opening on the upper surface of the processing tank 10 and entering the processing tank 10. By maintaining the state in which the object to be coated W is being poured into the downward flow of the paint beads for a predetermined time, the paint beads are brought into contact with the object to be coated W and the powder paint is attached to the object to be coated W. And a step of driving the air cylinder 70 after the coating step and pulling up the workpiece W from the downward flow of the paint beads (pickup step).

  According to this embodiment, the workpiece W is thrown into the coating beads flowing in the treatment tank 10, so that the loading load is reduced. Further, since the object to be coated is lowered and introduced during the downward flow of the paint beads formed in the processing tank 10, the direction in which the object W is charged coincides with the flow direction of the paint beads. For this reason, the input load is further reduced.

  Further, by vibrating the processing tank 10 in the horizontal direction by the vibration device 50, the flow of the coating beads temporarily filled in the processing tank 10 is promoted. For this reason, the downward flow of the paint beads is continuously formed in the treatment tank 10 without stagnation. The input load required for charging the coating material during the downward flow of the paint beads that do not stagnate is greater than the input load required when the coating material is input during the downward flow of the paint beads that are partially stagnant. Is also small. Therefore, by making the treatment tank 10 vibrate in the horizontal direction by the vibration device 50 and forming a downward flow that does not stagnate, the input load when the workpiece W is input during the downward flow of the paint beads is further reduced. .

  In addition, since the entire coating apparatus 1 is not vibrated by the vibration device 50, but only the treatment tank 10 is vibrated, the treatment tank 10 can be vibrated using a small vibration motor 52. For this reason, the coating apparatus 1 can be comprised compactly.

  In addition, since the elongated workpiece W is lowered along the longitudinal direction and is introduced into the downward flow of the coating beads, the charging area at the time of charging can be reduced. Therefore, the input load can be further reduced.

  When a long object to be coated was applied by the method shown in the present embodiment, the input load required to input the object to be coated during the downward flow of the paint beads was 5 to 6 kgf. On the other hand, in the case where the coating object is painted by filling the processing tank with the paint beads and burying the long coating object in the coating bead layer filled in the state where the processing tank is vibrated. The charging load required when charging the object to be coated into the paint bead layer was 20 kgf or more. This also shows that the input load is greatly reduced by the method shown in this embodiment.

  In addition, a conventional painting method (a method in which a coating object is buried in a coating bead layer filled in a processing tank) is applied to a lifting load required when the coating object W is pulled up from the downward flow of the coating beads. It was possible to make it smaller than the required lifting load.

  The paint beads are sufficiently stirred in the first cylinder 21 and the second cylinder 31 by the rotation of the first screw 22 and the second screw 32. For this reason, the paint beads flowing in the treatment tank 10 are also sufficiently stirred. Since the sufficiently stirred paint beads are brought into contact with the article to be coated W in the treatment tank 10, the powder paint can be uniformly attached to the article to be coated W.

DESCRIPTION OF SYMBOLS 1 ... Coating apparatus, 10 ... Processing tank, 20 ... 1st transfer part, 21 ... 1st cylinder, 21a ... Hopper, 22 ... 1st screw, 23 ... 1st drive motor, 30 ... 2nd transfer part, 31 ... 1st 2 cylinders, 32 ... second screw, 33 ... second drive motor, 40 ... transfer passage, 41 ... opening at the other end, 50 ... vibration device, 60 ... stand, 70 ... air cylinder (actuator), 71 ... cylinder body 72 ... Cylinder rod, W ... Workpiece

Claims (4)

A treatment tank in which a cylindrical space extending in the vertical direction is formed inside and an upper surface and a lower surface are opened;
A cylindrical space extending in the horizontal direction is formed inside, and is disposed below the processing tank, and has a first cylinder in which an opening is formed at a position facing an opening portion on the lower surface of the processing tank, A first transfer unit having a first screw disposed coaxially in one cylinder, and a first drive motor connected to the first screw and rotating the first screw;
A cylindrical space extending in the vertical direction is formed inside, a second cylinder connected to an end of the first cylinder, a second screw arranged coaxially in the second cylinder, and the second screw A second transfer motor having a second drive motor connected to the second drive motor for rotating the second screw;
One end side of the second cylinder opens to a portion located above the portion to which the end portion of the first cylinder is connected, and the other end side opens to the treatment tank side;
An actuator that drives the article to be moved in the vertical direction so that the article falls from the opening on the upper surface of the treatment tank and enters the treatment tank;
Equipped with a,
A coating apparatus for adhering the powder paint to the object to be coated by contacting the object with the powder paint adhering to the surface of the coating medium filled in the treatment tank,
In the treatment tank, a downward flow is formed in which the coating medium flows downward from above,
The said actuator drives the said to-be-coated object so that a to-be-coated object descend | falls from the opening part of the upper surface of the said processing tank, and a to-be-coated object is thrown in in the said downward flow . The coating apparatus according to claim 1,
The said actuator drives the said to-be-coated object so that the said to-be-coated object in the said downward flow may be pulled upwards. In the coating device according to claim 1 or 2,
A coating apparatus comprising a rubber tube connecting the opening on the lower surface of the treatment tank and the opening on the first cylinder. Using coating apparatus according to any one of claims 1 to 3 A coating method for coating the object to be coated,
By supplying a coating medium having a powder coating adhered to the surface thereof into the treatment tank and driving the first drive motor and the second drive motor to rotate the first screw and the second screw, Forming a circulating flow of the coating medium so that a downward flow in which the coating medium flows downward from above in the treatment tank is continuously formed;
Driving the actuator and lowering the object to be coated from the opening on the upper surface of the processing tank and entering the processing tank;
Maintaining the state in which the article is being thrown into the downflow for a predetermined time, bringing the paint medium into contact with the article and attaching the powder coating to the article; ,
A method for painting an object to be coated.

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