JP2016182570A - Coating gun - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a coating gun which prevents a paint from adhering on a side surface.SOLUTION: A coating gun is provided with a paint jetting part which is arranged on a front end surface and jets a mist-like paint, and an air jetting port for expulsion 30 arranged on a tapered surface 28S on a tip end side of a side surface. The paint floating in the air is kept away from the tapered surface 28S by jetting air for paint expulsion from the air jetting port for expulsion 30 to suppress adhesion of the paint on the tapered surface 28S.SELECTED DRAWING: Figure 3

Description

  The present invention relates to a coating gun provided with a paint spraying portion for spraying a mist-like paint on a front end surface.

  This type of paint gun is attached to a robot in a paint line, for example, and used in various postures. In addition, if the paint adheres to the paint gun and hardens, it can become a paint bottle and fall off on the workpiece, so the painting line is provided with a cleaning pot to clean the front end face of the paint gun (For example, refer to Patent Document 1).

Japanese Patent Laying-Open No. 2003-1148 (FIG. 1, claim 1)

  By the way, in the coating gun described above, the paint usually adheres only to the front end surface having the paint jetting part, but the paint may adhere to the side surface of the paint gun depending on various conditions such as the posture and moving speed during painting. , It could take time and effort to clean.

  The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a coating gun in which a paint hardly adheres to a side surface.

  In order to achieve the above-mentioned object, the invention of claim 1 is a coating gun having a paint spraying portion for spraying paint in a mist form on the front end surface, in a paint spraying region from the paint spraying portion. On the other hand, the paint gun is provided with a discharge air jet port on the side surface for discharging the paint discharge air in a direction deviating from the side.

  A second aspect of the present invention is the coating gun according to the first aspect, wherein the discharge air outlet is unevenly distributed at one place in the circumferential direction of the side surface.

  According to a third aspect of the present invention, the side surface is provided with a tapered surface having a diameter reduced toward the front end surface and having the exhaust air jet port, and the central axis of the exhaust air jet port is the tapered surface. The coating gun according to claim 1, wherein the coating gun is tilted rearward from a position orthogonal to the position.

  According to a fourth aspect of the present invention, the paint spraying portion is disposed around a rotary atomizing head that is driven to rotate and discharges the paint diagonally forward by centrifugal force, and the rotary atomizing head. A plurality of spraying air jets for spraying spraying air toward the paint discharged from the inside, and on the inner side of the side surface, the air is supplied from the air feeding path to the spraying air jetting port. The air supply path is branched, and the end thereof forms the exhaust air outlet, and the opening diameter of the exhaust air outlet is smaller than the opening diameter of the spray air outlet. A paint gun according to any one of the claims.

[Invention of Claim 1]
According to the first aspect of the present invention, the paint discharge air is ejected from the discharge air outlet provided on the side surface, and the paint floating in the air is kept away from the side surface, thereby preventing the paint from adhering to the side surface. This eliminates the time and effort required to clean the paint gun.

[Invention of claim 2]
In the painting gun according to claim 2, when coating is performed while moving to the side, if the discharge air jet outlet is disposed at a position on the rear side in the moving direction, usually the rear side in the moving direction of the coating gun. The negative pressure generated in the paint gun is no longer generated by the paint waste air ejected from the waste air ejection port, thereby preventing the paint from adhering to the side surface of the paint gun.

[Invention of claim 3]
In the paint gun according to claim 3, since the position near the front end of the side surface is a tapered surface, the interference with the work is reduced, but the paint easily adheres, but the taper surface is provided with an air outlet for discharge. As a result, adhesion of paint can be suppressed.

[Invention of claim 4]
In the configuration of claim 4, since the auxiliary air supply path is branched from the air supply path for supplying air to the spray air jet outlet and the end thereof forms the discharge air jet outlet, A part of the supply path for the waste air is shared, and the structure is simplified.

Sectional drawing of the painting booth and painting line concerning one embodiment of the present invention Side view of the paint gun head Side cross-sectional view of the paint gun head Front view of paint gun head Conceptual diagram showing the airflow when the paint gun moves The front view of the head part of the painting gun which concerns on the modification of this invention The front view of the head part of the painting gun which concerns on the modification of this invention Side view of a paint gun according to a modification of the present invention

  Hereinafter, an embodiment of the present invention will be described with reference to FIGS. FIG. 1 shows a painting line 13 covered with a painting booth 10. The painting booth 10 is provided with a ceiling plate 11 and a floor plate 12 having a mesh structure, and compressed air is supplied to the attic room 11A above the ceiling plate 11, while air is sucked from the under floor room 12A below the floor plate 12. Has been. Thereby, air is always blown down into the painting booth 10. In addition, the flow velocity of the air blown down is, for example, about 300 [mm / s].

  The painting booth 10 extends in a direction perpendicular to the paper surface of FIG. 1 and moves in the center of the floor plate 12 in the width direction with the carriage 14 mounted with the workpiece W. The painting robots 15 and 15 are arranged on both sides of the moving path of the transport carriage 14 to form a painting line 13.

  A coating gun 20 according to the present invention is attached to the tip of the arm 15A of each coating robot 15. The coating gun 20 includes an extension arm portion 21 that extends on an extension line of the arm 15 </ b> A, and a head portion 22 that extends obliquely forward from the front end of the extension arm portion 21. As shown in FIG. 2, the front end face of the head portion 22 is provided with a rotary atomizing head 23 at the center, and a plurality of atomizing air jets 24 according to the present invention surrounding the rotary atomizing head 23. (Refer to FIG. 4) is provided, and the coating atomizing portion 25 according to the present invention is constituted by the rotary atomizing head 23 and the atomizing air outlet 24 group.

  As shown in FIG. 3, the rotary atomizing head 23 is attached to a rotor 26 </ b> R of a hollow motor 26 built in the head portion 22. Further, the tip of the rotary atomizing head 23 is provided with a bell cup portion 23 </ b> A that gradually increases in diameter toward the front, and the bell cup portion 23 </ b> A protrudes from the tip surface of the head portion 22. Then, in a state where the rotary atomizing head 23 is rotationally driven, the paint is supplied into the rotary atomizing head 23 from the paint supply path 26A at the center of the rotor 26R, and the paint is fed from the tip of the bell cup portion 23A by centrifugal force. It is discharged and atomized so as to expand in a tapered shape.

  As shown in FIG. 4, the atomizing air outlets 24 group are located outside the bell cup portion 23 </ b> A when viewed from the front of the head portion 22 and open toward the front. Then, as shown in FIG. 3, the atomizing air according to the present invention is ejected forward from the atomizing air outlet 24 group, and the above-mentioned atomized paint is sent forward. In this way, the paint is sprayed from the paint spraying part 25 on the front end face of the head part 22 and sprayed onto the workpiece W.

  In FIG. 3, the mist particles of the paint are schematically shown as particles having a symbol T, and the air ejected from the spray air outlet 24 and the discharge air outlet 30 described later is denoted by the symbol T. It is schematically shown by “points” smaller than the attached “grains”.

  In order to supply air to the atomizing air outlets 24 group, a plurality of air supply passages 29 are formed in a ring shape inside the head portion 22. Specifically, the front end portion of the head portion 22 includes, for example, a head intermediate base 27 fitted to the front end portion of the hollow motor 26 and a head front end base 28 attached to the front surface of the head intermediate base 27. Has been. The head tip base 28 has a truncated cone shape with a tapered diameter, and the side surface of the head tip base 28 is a tapered surface 28S according to the present invention. In addition, a through hole 28A is formed in the central portion of the head distal end base 28 in which the proximal end portion of the rotary atomizing head 23 is loosely fitted.

  The plurality of air supply paths 29 described above are substantially parallel to the tapered surface 28S of the head distal end base 28 and extend from a position near the outer edge of the base end surface of the head distal end base 28 to a position near the front end of the head distal end base 28. . A tip communication path 29A that communicates between the tip of each air supply path 29 and the front end surface of the head tip base 28 is formed in parallel with the central axis of the head tip base 28, and each of these tip connection paths. The end of 29A is an air outlet 24 for spraying.

  An annular air supply path 27A is formed in a portion of the head intermediate base 27 that overlaps with the base end surface of the head distal end base 28, and the base end portions of all the air supply paths 29 communicate with the annular air supply path 27A. doing. Then, compressed air is supplied to each air supply path 29 from an air supply source (not shown) via an air introduction path 27B extending rearward from the annular air supply path 27A. Further, an explosion-proof electromagnetic valve (not shown) is provided in the compressed air supply path to the air introduction path 27B, and the ejection of air from the spraying air outlet 24 is turned on and off by the electromagnetic valve.

  Now, in the coating gun 20 of the present embodiment, the exhaust air outlet 30 according to the present invention is formed in the head tip base 28. Specifically, a plurality of sub air feed paths 31 are branched from the air feed path 29 inside the head tip base 28, and the ends of the sub air feed paths 31 become a plurality of discharge air jets 30. In addition, for example, five such discharge air outlets 30 are provided as shown in FIG. Of these, three exhaust air outlets 30 are provided at the end of a group of sub air feed paths 31 communicating with a common air feed path 29, and are arranged in a line in the axial direction of the head tip base 28. The taper surface 28S is disposed at a position near the front end, an intermediate position, and a position near the rear end. The remaining two exhaust air outlets 30 and 30 are disposed on both sides of the exhaust air outlet 30 near the front end, and adjacent to the air supply path 29 where the three exhaust air outlets 30 communicate with each other. It communicates with the air supply paths 29 and 29.

  In addition, the central axis of each sub air supply path 31 faces in a direction perpendicular to the central axis of the head tip base 28. As a result, the air ejected from the discharge air ejection port 30 does not affect the paint ejection region R1 ejected from the paint ejection part 25 of the coating gun 20. Further, the opening diameter of each exhaust air outlet 30 is smaller than the opening diameter of the atomizing air outlet 24.

  This completes the description of the configuration of the coating gun 20 of the present embodiment. Next, the effect of the coating gun 20 will be described. When the transporting carriage 14 is placed at a predetermined position with respect to the painting robot 15 waiting at a preset origin position, the painting robot 15 is operated so that the tip surface of the painting gun 20 faces the workpiece W and sprays. The rotary atomizing head 23 is driven to rotate after the atomizing air is ejected from the air outlets 24 group. Thereby, the paint is atomized and sprayed onto the workpiece W. At that time, the paint that has not adhered to the workpiece W is sucked into the underfloor room 12A by the blown-down air in the painting booth 10 and removed. As a result, normally, the paint hardly adheres other than the front end face of the coating gun 20. Then, the cleaning liquid is applied to the front end surface of the coating gun 20 in a state where the front end portion of the coating gun 20 is received in a cleaning pot (not shown) provided in the coating line 13 to clean only the coating material spraying portion 25.

  By the way, depending on the kind or site | part of the workpiece | work W used as coating object, coating may be performed in the condition where the blow-down air in the coating booth 10 is hard to reach. Specifically, when the inside of the vehicle body as the work W is painted, or when the vehicle door as the work W is laid down horizontally, it is fixed to the transport carriage 14 and the inner plate of the vehicle door is viewed from below. In the case of painting or the like, it is difficult for the blown-down air to reach. For this reason, as shown in FIG. 5 (A), the mist-like paint floats in the vicinity of the movement path of the painting gun 20. Under such circumstances, for example, when coating is performed while moving the conventional coating gun 20Z that does not have the discharge air jet port 30 to the side (right direction in FIG. 5A), the rear side in the moving direction. As a result, the mist-like paint T is attracted to the side surface of the coating gun 20 by the negative pressure generated (see FIG. 5A), and as a result, the paint T1 adheres to the tapered surface 28S which is the side surface of the tip portion of the coating gun 20. Sometimes.

  In such a case, in the coating gun 20 of this embodiment, as shown in FIG. 5 (B), the waste air jets 30 group may be arranged on the rear side in the moving direction to perform coating. In this case, the negative pressure that normally occurs on the rear side in the moving direction of the coating gun 20 is not generated by the paint discharge air ejected from the discharge air outlet 30, and thereby the taper surface 28 </ b> S of the coating gun 20. The adhesion of paint is prevented. This eliminates the time and effort required to clean the coating gun 20.

  The coating gun 20 is coated while moving sideways at a speed of, for example, 600 [mm / s] under conditions where the blown-down air does not reach. A comparative experiment was conducted with and without. As a result, in the case where the group of exhaust air jets 30 is not provided, the paint adheres to the rear part of the moving direction in the side surface of the coating gun 20, and in the case where the group of exhaust air jets 30 is provided, the paint is applied. It was confirmed that no paint adhered to the side of the gun 20.

[Other Embodiments]
The present invention is not limited to the above-described embodiment. For example, the embodiments described below are also included in the technical scope of the present invention, and various other than the following can be made without departing from the scope of the invention. It can be changed and implemented.

(1) In the embodiment described above, the group of exhaust air jets 30 is unevenly distributed at one place in the circumferential direction of the coating gun 20, but the circumferential direction of the tapered surface 28S is similar to the coating gun 20V shown in FIG. The exhaust air outlets 30 group may be unevenly distributed at two locations, or the entire circumferential direction of the tapered surface 28S as in the coating guns 20W and 20X shown in FIGS. 7 (A) and 7 (B). You may arrange | position the air spout 30 for evacuation equally.

(2) The group of exhaust air jets 30 of the above-described embodiment ejects paint exhaust air in a direction orthogonal to the central axis of the head portion 22 of the coating gun 20. The direction in which the paint discharge air is ejected may be in any direction as long as it deviates from the paint ejection region R1 from the paint ejection section 25.

(3) In the above-described embodiment, the group of the discharge air jets 30 is formed on the tapered surface 28S of the side surface of the coating gun 20, but the central axis of the head portion 22 as in the coating gun 20Y shown in FIG. An air outlet 30 for evacuation may be formed on a side surface parallel to the surface.

20, 20V, 20W, 20X, 20Y Coating gun 23 Rotating atomizing head 24 Spraying air outlet 25 Paint spraying part 28S Tapered surface 29 Air supply path 30 Waste air outlet 31 Sub air supply path R1 ejection area

Claims (4)

A paint gun provided on the front end surface with a paint spraying part for spraying paint in the form of a mist,
A coating gun provided with a discharge air outlet on a side surface for discharging paint discharge air in a direction deviating from a spray region of the paint from the paint spraying portion.   The coating gun according to claim 1, wherein the exhaust air outlet is unevenly distributed at one place in a circumferential direction of the side surface.   The side surface is provided with a tapered surface having a diameter that decreases toward the front end surface and has the exhaust air outlet, and a central axis of the exhaust air outlet is a rear side from a position orthogonal to the tapered surface. The paint gun according to claim 1 or 2, wherein The paint spraying portion is rotationally driven and discharges the paint obliquely forward by centrifugal force, and is disposed around the rotary atomization head and directed toward the paint discharged from the rotary atomization head. A plurality of spraying air jets for spraying spraying air,
A sub-air supply path is branched from an air supply path for supplying air to the spraying air outlet on the inner side of the side surface, and the terminal of the auxiliary air supply path forms the exhaust air outlet, and the exhaust air outlet The coating gun according to any one of claims 1 to 3, wherein an opening diameter of the spraying air is smaller than an opening diameter of the spraying air outlet.

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