JP2008264736A - Coating method and coating apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a coating method, in which the productivity is improved by dispensing with the removal of a masking member after a coating step and excellent product finish is secured, and a coating apparatus used for carrying out the method. <P>SOLUTION: In the coating method, a coating film constituted of a fluorescent body or a protective film is applied on the side outer surface 1a of a hollow rod like tubing material 1 for an electrodeless discharge lamp by spray coating using a spray nozzle 11. The masking member 12 is arranged between a non-coating area 3 of the tubing body 1 and the spray nozzle 11 in a non-contact state. By moving the spray nozzle 11 for spraying the coating material in parallel to the axial direction of the tubing material1 while rotating the tubing material 1 around the axis, a coating material sprayed from the spray nozzle 11 and headed to the non-coating area 3 is intercepted by the masking member 12. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a coating method and a coating apparatus used for carrying out this method.

  Conventionally, in order to leave the non-painted area on the side outer surface of the rod-shaped material and apply the coating only to the painted area, cover the rod-shaped material by applying a masking member only to the non-painted area of the rod-shaped material, and cover the rod-shaped material around its axis. And a spray nozzle for injecting paint is moved along the axial direction of the rod-shaped material. According to this, the paint can be applied only to the paint area on the side outer surface of the rod-shaped material.

However, the masking member adhered to the non-painted area of the rod-shaped material must be peeled off after painting, which not only reduces the manufacturability by removing the masking member after the painting process, but also damages the rod-shaped material at the time of removal. There was also a risk of generating defective products.
JP 2002-66407 A

  The present invention has been made in view of the above points. The object of the present invention is to improve the productivity without requiring removal of the masking member after the coating process and to ensure a good product finish. It is an object of the present invention to provide a method and a coating apparatus used for the implementation.

  In order to solve the above-mentioned problem, in the coating method according to claim 1, a coating film made of a phosphor or a protective film is sprayed on the side outer surface 1a of the hollow rod-shaped tube material 1 for an electrodeless discharge lamp. This is a coating method in which spray coating from a nozzle 11 is applied, and a masking member 12 is arranged in a non-contact state between a non-coating area 3 of the tube material 1 and the spray nozzle 11, and the tube material 1 is rotated around an axis. The masking member 12 blocks the paint sprayed from the spray nozzle 11 toward the non-painting region 3 by moving the spray nozzle 11 for spraying the paint in parallel with the axial direction of the tube material 1 while moving. It is characterized by.

  According to this, since the paint sprayed from the spray nozzle 11 is blocked by the masking member 12 only in the paint directed to the non-painting area 3, the non-coated surface 1 a of the hollow rod-like tube material 1 for electrodeless discharge lamps The paint area does not reach the paint area 3 and the paint film does not adhere to it, and the paint film reaches only the paint area 2 and the paint film can be applied. Since it is arranged in a non-contact state between the non-coating area 3 and the spray nozzle 11, it is necessary to remove the masking member 12 from the tube material 1 as before after painting the hollow rod-like tube material 1 for an electrodeless discharge lamp. Therefore, the coating can be performed with good manufacturability. Furthermore, according to the fact that it is not necessary to remove the masking member 12 from the pipe material 1 as in the prior art, it is possible to avoid the pipe material 1 from being damaged during the removal process from the pipe material 1 of the masking member 12. Good manufacturing finish can be secured.

  Further, in the painting method according to claim 2, in claim 1, the air flow A is caused to flow toward the coating area 2 of the pipe material 1 in the gap S <b> 1 between the masking member 12 and the non-coating area 3 of the pipe material 1. It is characterized by.

  According to this, the paint which goes around the gap S1 between the masking member 12 and the pipe material 1 and goes toward the non-painting area 3 of the pipe material 1 is applied to the gap S1 between the masking member 12 and the non-painting area 3 of the pipe material 1. It can be placed on the airflow A that has flowed toward the painting area 2 of 1 and flow toward the painting area 2 of the pipe material 1, and the coating material 1 can be prevented from adhering to the non-coating area 3. The paint finish can be improved.

  Further, in the coating method according to claim 3, when the spray nozzle 11 that has moved reaches the boundary between the coating region 2 and the non-coating region 3, the coating material injection port 11a is connected to the tube material 1 according to claim 1. The spray nozzle 11 is rotated around the paint injection port 11a so as to face the coating area 2 side of the paint.

  According to this, when the moved spray nozzle 11 reaches the boundary between the painting area 2 and the non-coating area 3, the spray nozzle 11 is rotated so that the paint injection port 11a is directed to the painting area 2 side of the pipe 1. Thus, it is possible to prevent the paint sprayed from the spray nozzle 11 from being directed to the non-painting area 3, and to prevent the coating material 1 from being attached to the non-painting area 3. By rotating the spray nozzle 11 around the paint injection port 11a, the distance between the paint injection port 11a of the spray nozzle 11 and the side outer surface 1a of the tube material 1 can be kept substantially constant, thereby causing uneven coating. In other words, the finish of the tube material 1 can be improved.

  Further, in the painting method according to claim 4, in the first aspect, the gap S2 between the tip bottom surface 1b of the tube material 1 which is the non-painting region 3 and the rectifying plate 13 disposed opposite to the tip bottom surface 1b is provided. A rapid flow B having an increased flow velocity is formed by flowing an injection flow from the spray nozzle 11, and a paint sprayed from the spray nozzle 11 and directed toward the bottom surface 1b of the tube 1 is placed on the rapid flow B and flows downstream of the gap S2. It is characterized by doing so.

  According to this, the rectifying plate 13 is arranged on the tip bottom surface 1b of the pipe material 1 which is the non-painting region 3 with a simple structure such that the jet flow from the spray nozzle 11 is made to flow rapidly B, and is opposed to the gap S2. Since it is possible to prevent the paint sprayed from the spray nozzle 11 from reaching the bottom surface 1b of the tube material 1 which is the region 3, it is possible to secure a good paint finish of the tube material 1 with a simple structure.

  Further, in the coating apparatus according to claim 5, a fluorescent or protective coating film is applied by spray coating from the spray nozzle 11 to the side outer surface 1 a of the hollow rod-shaped tube 1 of the electrodeless discharge lamp. A coating apparatus 10 for installing a pipe 1 to be coated, a spray nozzle 11 for spraying paint while moving in the axial direction of the pipe 1 installed in the installation 14, and an installation 14 A rotating mechanism 15 that rotates the installed pipe 1 around its axis, and a masking member 12 that is arranged in a non-contact state between the non-painting area 3 of the pipe 1 installed in the installation section 14 and the spray nozzle 11. It is characterized by comprising.

  According to this, when coating is applied to the side outer surface 1a of the hollow rod-shaped tube material 1 for the electrodeless discharge lamp installed in the installation portion 14, only the paint directed to the non-coating area 3 out of the paint sprayed from the spray nozzle 11 is applied. It can be blocked by the masking member 12, that is, on the side outer surface 1a of the tube material 1, the paint is not applied to the non-coating area 3 and the coating film is not applied to the non-coating area 3; Further, at this time, the masking member 12 is disposed in a non-contact state between the non-painting area 3 of the tube material 1 and the spray nozzle 11, so that a hollow for an electrodeless discharge lamp is used. Since it is not necessary to remove the masking member 12 from the tube material 1 after the coating of the rod-shaped tube material 1, it is possible to perform the coating with good manufacturability. Furthermore, according to the fact that it is not necessary to remove the masking member 12 from the pipe material 1 as in the prior art, it is possible to avoid the pipe material 1 from being damaged during the removal process from the pipe material 1 of the masking member 12. Good manufacturing finish can be secured.

  Further, in the coating apparatus according to claim 6, in claim 5, the air nozzle 16 that causes the airflow A to flow toward the coating area 2 of the pipe material 1 in the gap S <b> 1 between the masking member 12 and the non-coating area 3 of the pipe material 1. When the moved spray nozzle 11 reaches the boundary between the coating area 2 and the non-painting area 3, the spray nozzle 11 is moved to the coating area 2 side of the tube material 1 so that the spray nozzle 11 is directed toward the coating area 2 side. The spray nozzle rotating means 17 that rotates about the center and the tip bottom surface 1b of the tube material 1 that is the non-coating region 3 are arranged to face each other with a gap S2, and an injection flow from the spray nozzle 11 flows through the gap S. A rectifying plate 13 for forming a rapid flow B with an increased flow velocity and placing the paint on the rapid flow B and sprayed from the spray nozzle 11 toward the bottom surface 1b of the pipe member 1 downstream of the gap S2. With features That.

  According to this, the paint that goes around the gap S1 between the masking member 12 and the pipe material 1 and goes to the non-painting area 3 of the pipe material 1 is placed in the gap S1 between the masking member 12 and the non-painting area 3 of the pipe material 1. It can be placed on the airflow A that flows from the air nozzle 16 toward the coating area 2 of 1 and flows toward the coating area 2 of the pipe 1, and the spray nozzle 11 that has moved moves between the painting area 2 and the non-coating area. The spray nozzle 11 is rotated around the paint spray port 11a by the spray nozzle rotating means 17 toward the coating area 2 side of the tube material 1 when the boundary with the nozzle 3 is reached. Thus, it is possible to prevent the paint sprayed from the spray nozzle 11 from being directed toward the non-painting area 3, and to maintain a substantially constant distance between the paint spraying port 11a of the spray nozzle 11 and the side outer surface 1a of the tube material 1. A simple structure in which the rectifying plate 13 is disposed opposite to the tip bottom surface 1b of the tube 1 that is the non-coating region 3 with a gap S2 flowing through the rapid flow B from the spray nozzle 11 is provided. Therefore, it is possible to prevent the paint sprayed from the spray nozzle 11 from reaching the bottom surface 1b of the pipe material 1 which is the non-painting region 3 by using the spray flow from the spray nozzle 11 which becomes the rapid flow B. A good paint finish of the tube 1 can be secured.

  In the present invention, when coating the outer side surface of the hollow rod-shaped tube of the electrodeless discharge lamp, the productivity is improved without the need to remove the masking member after the coating process, and a good product (painted ) It has the advantage that the finish can be secured.

  Hereinafter, the present invention will be described based on embodiments shown in the accompanying drawings.

  A coating apparatus 10 shown in FIGS. 1 to 7 applies a coating film of a phosphor or a protective film by spray coating from a spray nozzle 11 on the side outer surface 1a of a hollow rod-shaped tube 1 of an electrodeless discharge lamp. That is, it is an apparatus for applying paint. Here, the hollow rod-shaped tube material 1 of the electrodeless discharge lamp has a cylindrical cavity portion 4 having a bottomed end surface (hereinafter referred to as a tip bottom surface 1b) at the tip as shown in FIG. A narrow tubular exhaust pipe 6 is integrally formed along with the cavity portion 4, and a flare portion 5 having an enlarged diameter is formed at the proximal end of the cavity portion 4. The exhaust pipe 6 has a distal end that reaches the distal end bottom surface 1 b of the cavity portion 4, and a proximal end that protrudes away from the distal end relative to the proximal end of the cavity portion 4.

  As shown in FIG. 2, the coating apparatus 10 of the present example has an installation part 14 for installing a hollow rod-like tube 1 of an electrodeless discharge lamp to be painted, and a paint while moving in the axial direction of the pipe 1 installed in the installation part 14. Spray nozzle 11, rotating mechanism 15 for rotating tube material 1 installed in installation unit 14 around its axis, and control unit (not shown) for controlling driving of coating apparatus 10.

  Specifically, a rail portion 18 is provided substantially horizontally on the frame 10 a of the coating apparatus 10, and a movable unit 19 including the spray nozzle 11 is movably provided along the rail portion 18. The movable unit 19 is allowed to travel in a predetermined range in the length direction of the rail portion 18 under the control of the control unit. Here, the movable unit 19 is provided with a traveling portion 20 that travels along the rail portion 18 in the upper portion and a coating portion 21 that includes the spray nozzle 11 in the lower portion. A spray air supply line 22 and a coating liquid supply line 23 are connected to the spray nozzle 11 so that paint can be sprayed in a predetermined range in a spray form from a paint injection port 11a provided at the lower end of the spray nozzle 11 (note that , The paint sprayed on T in the figure).

  The coating portion 21 is provided with a spray nozzle rotating means 17 for rotating the spray nozzle 11 up and down on the axis of the tube material 1 around the paint injection port 11a. As shown in FIG. 3, the spray nozzle rotating means 17 includes a driving motor 24, a nozzle driving first pulley 25 connected to the driving motor 24, and a nozzle driving first pulley, which are installed on the frame 21 a of the coating unit 21. 1 pulley 25 and a nozzle driving second pulley 27 connected by a timing belt 26. The spray nozzle 11 is disposed via a nozzle bracket 28 on a nozzle driving first pulley 25 and a nozzle driving second pulley 27 that is rotationally driven via a timing belt 26 according to the rotational driving of the driving motor 24. In addition, a slit cam 29 is provided. The slit of the slit cam 29 that rotates along with the rotation of the second pulley 27 for driving the nozzle is detected by the photosensor 30 installed on the frame 21a of the coating unit 21, and the drive control of the drive motor 24 is performed by feedback control of the control unit. Thus, the rotation angle of the spray nozzle 11 that rotates with the rotation of the second pulley 27 for driving the nozzle can be controlled. Here, the spray nozzle 11 is configured to be rotatable about the paint spraying port 11a. In addition, the coating part 21 of this example is movable up and down by an air cylinder 31 provided in the traveling part 20.

  Further, the installation unit 14 is configured by a space below the coating unit 21 in the coating apparatus 10. In order to install the pipe material 1 to be coated on the installation portion 14, the base end of the exhaust pipe 6 of the pipe material 1 is attached to a chuck 15 a provided at the output end of the rotation mechanism 15 as shown in FIG. 2. The coating apparatus 10 of this example operates the rotating mechanism 15 to rotate the tube 1 around its axis, and moves the spray nozzle 11 that sprays the paint in parallel to the axial direction of the tube 1, so that the tube 1 The side outer surface 1a is painted, but in detail, only the portion of the side outer surface 1a excluding the vicinity of the flare portion 5 of the tube material 1 is coated. That is, the portion of the side outer surface 1a in the vicinity of the flare portion 5 of the tube material 1 (region of 5 to 10 mm from the base end to the tip end of the tube material 1) is the non-coating region 3, and the tube material 1 excluding the vicinity of the flare portion 5 is provided. A portion of the side outer surface 1a (cross-hatched portion in the figure) is a coating area 2. Of course, the tip bottom surface 1b of the tube material 1 which is not the side outer surface 1a of the tube material 1 is also the non-coating region 3. As will be described in detail below, the coating apparatus 10 of the present example has a device for ensuring a good coating finish of the tube material 1 by attaching the paint only to the coating area 2 without attaching the paint to the non-painting area 3. Is given.

  In order to prevent the paint from adhering to the non-painting area 3 in the vicinity of the flare part 5 of the pipe material 1 in the coating apparatus 10 of this example, the non-painting area 3 and the spray of the pipe material 1 installed in the installation part 14 as shown in FIG. A masking member 12 disposed in a non-contact state in the space between the nozzle 11 and an air flow A toward the coating region 2 of the pipe member 1 in a gap S1 between the masking member 12 and the non-coating region 3 of the tube member 1. And an air nozzle 16 for flowing air. Here, an air supply line 32 is connected to the air nozzle 16. In the figure, 32a is a blower.

  The masking member 12 of this example is a plate-like member, and is disposed so as to be inclined so that the upper surface of the masking member 12 becomes lower toward the coating region 2 side. According to this masking member 12, only the paint directed to the non-painting region 3 among the paints sprayed from the spray nozzle 11 can be blocked. Therefore, in the side outer surface 1 a of the hollow rod-like tube material 1 for an electrodeless discharge lamp, The non-painting area 3 does not reach the coating material and does not deposit the coating film, and the coating material reaches only the coating area 2 and can apply the coating film. Here, since the masking member 12 is disposed in a non-contact state between the non-coating region 3 of the tube material 1 and the spray nozzle 11, as in the conventional case after the coating of the hollow rod-shaped tube material 1 for an electrodeless discharge lamp. It is not necessary to remove the masking member 12 from the pipe material 1, and it is possible to perform coating while ensuring good manufacturability. By eliminating the need to remove the masking member 12 from the tube material 1 as in the prior art, it is possible to avoid creating a scratch on the tube material 1 during the removal process from the tube material 1 of the masking member 12, and a good manufacturing finish of the tube material 1 There is also an advantage that can be secured. Note that the masking member 12 is detachable from the coating apparatus 10 so as to allow replacement after aged use.

  Further, in this example, the gap S1 between the masking member 12 and the non-painting area 3 of the electrodeless discharge tube is formed narrower as it approaches the painting area 2, and the masking member 12 is formed in the gap S1 as shown in FIG. Air nozzles 16 are arranged so as to extend over substantially the entire width. The narrow width of the gap S1 is preferably 5 mm or less. According to the formation of the airflow A flowing toward the coating area 2 of the pipe material 1 in the gap S1 between the masking member 12 and the non-coating area 3 of the pipe material 1 by the air injection from the air nozzle 16, the masking member 12 and the pipe material 1 The coating material which goes around the gap S1 and travels toward the non-painting area 3 of the pipe material 1 can be placed on the air flow A and flow toward the painting area 2 of the pipe material 1, Since the adhesion to the coating area 3 can be prevented, the finish of the tube material 1 is improved. Note that the masking member 12 of this example is inclined so that the upper surface to which the sprayed paint adheres is directed downward toward the coating region 2 side of the tube material 1, so that the masking member 12 on the coating region 2 side of the tube material 1 in the masking member 12. Although the paint may be dripped from the end portion, the paint to be dripped can also be caused to flow through the coating area 2 of the pipe material 1 by the air flow A, so that the paint does not adhere to the non-coating area 3 of the pipe material 1 and the pipe material. It is possible to ensure a good paint finish of 1. Furthermore, the air injection from the air nozzle 16 may be operated by the control unit when the movable unit 19 reaches a position where the non-painting area 3 of the pipe material 1 is included in the paint injection area of the spray nozzle 11. In this case, air injection from the air nozzle 16 can be performed only when necessary, and labor saving of the coating apparatus 10 can be achieved.

  Moreover, in the coating apparatus 10 of this example, in order not to make the paint adhere to the non-painting area 3 of the tip bottom surface 1b of the tube material 1, it is arranged to face the tip bottom surface 1b of the tube material 1 which is the non-painting area 3 with a gap S2. A straightening plate 13 is provided. According to the current plate 13, as shown in FIG. 7, the rapid flow B having a flow velocity increased by flowing the spray flow from the spray nozzle 11 is formed in the gap S <b> 2 with the tip bottom surface 1 b of the tube material 1, and is placed on the rapid flow B. The paint sprayed from the spray nozzle 11 and directed toward the tip bottom surface 1b of the tube material 1 can be made to flow downstream of the gap S2, and thereby the paint can be prevented from adhering to the non-painting region 3 of the tip bottom surface 1b of the tube material 1. . In other words, the rectifying plate 13 is arranged on the bottom surface 1b of the pipe material 1 in the non-painting region 3 so as to face each other with a gap S2 flowing through the rapid flow B from the spray nozzle 11, and the non-painting region 3 Thus, the coating material sprayed from the spray nozzle 11 is prevented from reaching the bottom surface 1b of the tube material 1, and a good paint finish of the tube material 1 can be secured with a simple structure.

  Moreover, in the coating apparatus 10 of this example, the spray nozzle 11 which moved the spray nozzle rotating means 17 by the control unit reached the boundary between the coating area 2 and the non-coating area 3 as shown in FIG. Sometimes, the coating material injection port 11a is rotated so as to be directed toward the coating region 2 side of the tube material 1. In this way, when the moved spray nozzle 11 reaches the boundary between the coating area 2 and the non-painting area 3, the spray nozzle 11 is rotated so that the coating material injection port 11a faces the painting area 2 side of the tube 1. Thus, it is possible to prevent the paint sprayed from the spray nozzle 11 from being directed toward the non-painting area 3. Further, since the rotation of the spray nozzle 11 is performed around the paint injection port 11a, the distance between the paint injection port 11a of the spray nozzle 11 and the side outer surface 1a of the tube material 1 can be kept substantially constant. Unevenness can be eliminated. In other words, it is possible to secure a good paint finish of the tube material 1.

  Specifically, when the spray nozzle 11 that moves along the axial direction of the tube material 1 is located above the coating area 2 of the tube material 1, as shown in FIG. It is held such that the opening direction of the coating material injection port 11a is substantially orthogonal to the side outer surface 1a of the tube material 1. When the moved spray nozzle 11 reaches the boundary between the non-coating zone 3 and the coating zone 2 in the vicinity of the flare portion 5 of the tube material 1, first, as shown in FIG. 6, first, substantially orthogonal to the side outer surface 1 a of the tube material 1. The spray nozzle 11 is rotated toward the coating area 2 of the tube material 1 at the position where the masking member 12 faces the spraying range of the spray nozzle 11 (arrow a), and then rotated toward the coating area 2 of the tube material 1. The spray nozzle 11 in a moved state is slid to the base end side (flare portion 5 side) of the tube material 1 (arrow b) such that the base end side of the spray range of the spray nozzle 11 does not exceed the masking member 12. The operation is performed by the control unit. On the other hand, when the moved spray nozzle 11 reaches the boundary between the non-painting area 3 and the painting area 2 on the bottom face 1b of the pipe material 1, the base end side of the spray range of the spray nozzle 11 is the pipe material 1 as shown in FIG. The operation of rotating the spray nozzle 11 toward the coating region 2 of the tube material 1 at a position located at the distal end portion of the side end surface of the tube is performed by the control unit. The coating of the side outer surface 1a of the tube material 1 may be terminated by moving the spray nozzle 11 in one axial direction of the tube material 1, or by reciprocating the spray nozzle 11 in the axial direction of the tube material 1. It may be terminated. The former can shorten the coating time, and the latter allows thick coating.

It is a schematic side view of the principal part of the coating apparatus of the example of embodiment of this invention. It is a schematic side view of a coating apparatus same as the above. It is a coating part of a coating apparatus same as the above, (a) is a schematic side view, (b) is a schematic front view. It is a schematic perspective view of the principal part of a coating apparatus same as the above. (A) (b) (c) is explanatory drawing explaining the coating operation | movement in a coating apparatus same as the above in order. It is explanatory drawing explaining the painting operation | movement in the principal part same as the above. It is explanatory drawing explaining the painting operation | movement in the other principal part same as the above. It is a schematic side view of the hollow rod-shaped tube material of the electrodeless discharge lamp which coats with the same coating apparatus.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Tubing material 1a Side outer surface 1b Tip bottom face 2 Painting area 3 Non-coating area 10 Coating device 11 Spray nozzle 11a Paint injection port 12 Masking member 13 Current plate 14 Installation part 15 Rotating mechanism 16 Air nozzle 17 Spray nozzle rotating means

Claims (6)

  A coating method in which a coating film composed of a phosphor or a protective film is applied to the outer side surface of a hollow rod-shaped tube material for an electrodeless discharge lamp by spray coating from a spray nozzle, and includes a non-painted area of the tube material The masking member is placed in a non-contact state with the spray nozzle, and the spray nozzle is sprayed from the spray nozzle by moving the spray nozzle parallel to the axial direction of the pipe while rotating the pipe around the axis. The coating method is characterized in that the coating material that goes to the non-painting area is blocked by a masking member.   The coating method according to claim 1, wherein an air flow is caused to flow toward a coating area of the pipe material in a gap between the masking member and the non-coating area of the pipe material.   When the moved spray nozzle reaches the boundary between the paint area and the non-paint area, the spray nozzle is rotated around the paint injection port so that the paint injection port faces the painting area of the pipe. The coating method according to claim 1.   A rapid flow with an increased flow velocity is formed by flowing an injection flow from the spray nozzle through the gap between the bottom surface of the pipe material, which is a non-coating area, and the rectifying plate arranged opposite to the bottom surface of the pipe. 2. The coating method according to claim 1, wherein the coating material directed toward the bottom of the tip of the pipe material is put on the rapid flow and flows downstream of the gap.   A coating device for applying a phosphor or protective coating film to the outer surface of the hollow rod-shaped tube of an electrodeless discharge lamp by spray coating from a spray nozzle, where an installation pipe is installed. A spray nozzle that sprays paint while moving in the axial direction of the pipe installed in the installation section, a rotation mechanism that rotates the pipe installed in the installation section around its axis, and a non-painting area of the pipe installed in the installation section And a spraying nozzle, and a masking member disposed in a non-contact state.   An air nozzle that flows airflow toward the coating area of the pipe material in the gap between the masking member and the non-painting area of the pipe material, and the spray nozzle when the moved spray nozzle reaches the boundary between the painting area and the non-painting area The spray nozzle rotating means for rotating the spray nozzle around the paint injection port so as to face the coating area side of the coating, and the bottom surface of the pipe material in the non-coating area are opposed to each other with a gap, and the spray is applied to the gap. A rectifying plate for flowing a spray flow from the nozzle to form a rapid flow with an increased flow velocity and carrying the paint directed from the spray nozzle toward the bottom of the tip of the pipe material on the rapid flow to the downstream of the gap. The coating apparatus according to claim 5, wherein the coating apparatus is formed.

Images