JP3880389B2 - Rotating bell type electrostatic coating equipment - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention provides a feed shaft that is housed in a feed tube outer cylinder in which a base end opening of a bell is attached to a distal end portion of the rotation shaft on a rotary shaft of an air motor formed in an annular shape so as to insert a feed tube outer cylinder. The rotating bell-type static is designed so that the paint discharged from the tube is atomized by the rotating bell and the rotating bell is cleaned by the cleaning liquid discharged from the gap between the feed tubes in the outer tube of the feed tube. The present invention relates to an electropainting device.
[0002]
[Prior art]
FIG. 5 shows a coating apparatus of this type. The cup-shaped bell 10 is driven to rotate while the rotation shaft tip 21a of the pipe-shaped rotation shaft 21 of the air motor 20 is attached to the proximal end opening 12 of the cup-shaped bell 10. A feed tube outer cylinder 30 accommodating a plurality of feed tubes 31 is inserted into the shaft 21 and protrudes from the proximal end opening 12. A cleaning liquid, for example, thinner, is supplied to the gap between the feed tubes 31 in the feed tube outer cylinder 30. The front plate 11 having one hole 11a at the center and a large number of holes 11b around the center is attached to the front of the bell 10, so that the paint discharged from the feed tube 31 is atomized by the rotation. The The air motor 20 is driven to rotate the rotary shaft 21 by being supplied with air from the air supply port 22, and by supplying air from the air shaper 28 to the back surface of the bell 10, the spray pattern can be adjusted by adjusting the wind pressure. Yes.
[0003]
As a result, the paint of the selected color is supplied from the supply port 24, discharged from the feed tube 31 toward the front plate 11, and charged and atomized by the rotation of the bell 10 to which a high voltage is applied. . Further, when cleaning the inside of the bell 10, for example, thinner supplied from the supply port 24 a in the rotating state is discharged from the gap between the feed tubes 31 toward the front plate 11.
[0004]
[Problems to be solved by the invention]
However, at the time of such cleaning, the thinner bounces off the front plate 11 because of its relatively low viscosity with respect to the paint, so that the periphery of the base end opening 12 of the bell 10 or the feed as shown in FIG. If the paint 1 adheres to the gap between the tube outer cylinder 30 and the rotary shaft 21 and is solidified, and therefore it is attempted to ensure the cleaning at the time of color change, the cleaning operation takes a long time, and the inner portion of the rotary shaft tip 21a is also increased. It was difficult to clean the gap.
[0005]
The present invention has been made in view of the above, and an object of the present invention is to provide a rotating bell type electrostatic coating apparatus that can easily and reliably clean the inside of the bell and the vicinity thereof with the cleaning liquid supplied from the feed tube side. And
[0006]
[Means for Solving the Problems]
In order to achieve this object, according to the present invention, a base end opening of a bell is provided at a distal end of a rotating shaft on a rotating shaft of an air motor formed in an annular shape so as to insert a feed tube outer cylinder. The paint discharged from the feed tube accommodated in the feed tube outer cylinder is atomized by a rotating bell, and is rotated by a cleaning liquid discharged from the gap between the feed tubes in the feed tube outer cylinder. In the rotating bell type electrostatic coating apparatus in which the bell is cleaned, the feed tube (31, 31a) is connected to the tip edge (30a, 30d ) of the tip portion (30b, 30c) of the feed tube outer cylinder (30) . from 30e) with projecting into the bell (10), tip edge (30a, 30d, 30e) is later than the leading end (12a) of the proximal end opening portion of the bell (10) (12) And characterized in that it.
[0007]
The cleaning liquid discharged from the retracted feed tube outer cylinder (30) is diffused by the rotation of the rotating shaft (21) in the process of moving toward the distal end (12a) of the base end opening (12) of the bell (10). The injection pressure is suppressed and the nozzle is injected at a wide angle into the bell. In order to diffuse the inside of the feed tube outer cylinder (30), the tip (30b, 30c) of the feed tube outer cylinder (30) is formed in a taper shape whose inner diameter gradually increases toward the front. Alternatively, according to the third aspect, both the inner diameter and the outer diameter of the distal end portion (30b) of the feed tube outer cylinder (30) are tapered so as to gradually increase toward the front.
[0008]
DETAILED DESCRIPTION OF THE INVENTION
A rotating bell electrostatic coating apparatus according to an example of the embodiment of the present invention will be described with reference to FIGS. FIG. 1 shows the main part of this rotary bell type electrostatic coating apparatus, and the overall basic configuration is the same as that already described in FIG. 5, and the same or equivalent parts will be described with the same reference numerals.
[0009]
The distal end portion 30b of the feed tube outer cylinder 30 inserted in the pipe-shaped rotating shaft 21 of the air motor that is driven to rotate by being supplied with air gradually has both an inner diameter and an outer diameter toward the front through a gap between the rotating shafts 21. The tip edge 30a of the bell 10 is set at a position retracted from the tip 12a of the base opening 12 of the bell 10, that is, the tip edge 21b of the rotary shaft tip 21a aligned therewith. Has been. As shown in FIG. 2, the feed tube outer cylinder 30 stores a feed tube 31 a that is color-changed at the center portion and a feed tube 31 of a dedicated color around it. For example, thinner is supplied. These seven feed tubes 31 and 31a protrude forward from the base end opening 12 as usual. The opening angle of the tapered tip portion 30b is set so that the extension line of the inner peripheral surface thereof reaches a position that is retreated from the tip edge 21b on the inner peripheral surface of the rotary shaft tip portion 21a.
[0010]
The paint discharged from the selected one of the feed tubes 31 and 31a to the front plate 11 of the rotating bell 10 is discharged as charged fine particles, and is coated according to the normal operating principle.
[0011]
When cleaning the bell 10, thinner is discharged from the gap 35 in the feed tube outer cylinder 30, diffused along the tapered tip 30 b, and further rotated in the process of reaching the tip edge 21 b of the rotating shaft 21. It is diffused by and sprayed at a wide angle. Therefore, the rebound is suppressed by the diffusion of the discharge range and the dispersion of the injection pressure, and the injection is performed not only toward the front plate 11 but also along the inner peripheral surface of the bell 10. As a result, the inner peripheral surface of the bell 10, the front plate 11, the feed tubes 31, 31a, and the inside of the rotary shaft distal end portion 21a are surely cleaned, and particularly to the periphery of the base end opening 12 and the inside of the rotary shaft distal end portion 21a. Adhesion and solidification of the paint is avoided.
[0012]
FIG. 3 shows another embodiment, and the distal end portion 30c of the feed tube outer cylinder 30 is formed in a tapered shape with an inner diameter gradually increasing toward the front, and a distal end edge 30d thereof. Is set so as to recede from the tip end edge 21b of the rotating shaft 21 and the taper-shaped inner peripheral surface extends from the tip edge 21b. As a result, the thinner discharged from the gap 35 is diffused along the tapered tip portion 30c, and further diffused by the rotation in the process of reaching the tip edge 21b of the rotating shaft 21, and injected at a wide angle. This embodiment is applicable also when the outer periphery of the rotating shaft 21 and the gap between the feed tube outer cylinders 30 are narrower than the illustrated state.
[0013]
FIG. 4 shows still another embodiment. In FIG. 4A, the gap between the rotary shaft 21 and the feed tube outer cylinder 30 is used instead of the tip portion of the feed tube outer cylinder 30 being tapered. The distal end edge 30e of the feed tube outer cylinder 30 is set at a position that is sufficiently larger than the distal end edge 21b of the rotating shaft 21 so that sufficient diffusion is performed by the presence of the rotation and the rotation of the rotating shaft 21. However, as shown in Fig. B, in the case of a structure including a rotary shaft portion 12c in which the inner diameter of the rotary shaft 21 changes greatly at the back, the paint 2 is applied to the corner portion as shown in FIG. In order to avoid sticking in the long-term use process, it is set in consideration of limiting the retreat position. Furthermore, it is necessary to consider the holding action of the feed tubes 31 and 31a by the feed tube outer cylinder 30.
[0014]
【The invention's effect】
According to the first aspect of the present invention, the cleaning liquid discharged from the outer tube of the feed tube is prevented from rebounding due to diffusion, and the inside of the bell is reliably cleaned, and the cleaning liquid is also discharged inside the rotating shaft or the base end opening of the bell. Since it becomes a flow path, it is reliably washed. In that case, according to claim 2, even if the gap between the feed tube outer cylinder and the rotary shaft is small, the diffusion angle can be set large, and according to claim 3, the diffusion angle can be further expanded.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view of a main part of a rotary bell electrostatic coating apparatus according to an embodiment of the present invention.
FIG. 2 is a front view of a feed tube of the rotating bell type electrostatic coating apparatus.
FIG. 3 is a cross-sectional view of a main part of a rotary bell type electrostatic coating apparatus according to another embodiment.
FIG. 4 is a cross-sectional view of a main part of a rotary bell type electrostatic coating apparatus according to still another embodiment.
FIG. 5 is a cross-sectional view of a conventional rotary bell type electrostatic coating apparatus.
6 is a view for explaining a cleaning operation of the rotary bell type electrostatic coating apparatus according to FIG. 5;
[Explanation of symbols]
10 Bell 12 Bell Base End Opening 21 Air Motor Rotating Shaft 21a Rotating Shaft Tip 21b Rotating Shaft Tip Edge 30 Feed Tube Outer Cylinders 30a, 30d, 30e Feed Tube Outer Cylinder Leading Edges 30b, 30c Tip,
31, 31a Feed tube 35 Clearance in feed tube outer cylinder

Claims (3)

The base end opening of the bell is attached to the tip of the rotating shaft on the rotating shaft of the air motor that is formed in an annular shape so that the outer tube of the feed tube is inserted. In the rotating bell type electrostatic coating device, the rotating bell is cleaned with the cleaning liquid discharged from the gap between the feed tubes in the outer tube of the feed tube while the paint is atomized by the rotating bell. ,
The feed tube protrudes from the distal end edge of the distal end portion of the feed tube outer tube into the bell, and the distal end edge recedes from the distal end of the base end opening of the bell. Electropainting equipment.   2. The rotating bell type electrostatic coating apparatus according to claim 1, wherein the inner diameter of the distal end portion of the feed tube outer cylinder is tapered so as to gradually increase toward the front.   2. The rotating bell type electrostatic coating apparatus according to claim 1, wherein a tip end portion of the feed tube outer cylinder is formed in a tapered shape in which both the inner diameter and the outer diameter gradually increase toward the front.

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