JP5421175B2 - Electrostatic coating equipment - Google Patents

Description

  The present invention relates to an electrostatic coating apparatus. Specifically, the present invention relates to an electrostatic coating apparatus that performs electrostatic coating by spraying paint from the tip of a rotary atomizing head.

  2. Description of the Related Art Conventionally, a rotary atomizing electrostatic coating apparatus is known as a coating apparatus for coating a car body or the like. This electrostatic coating apparatus is rotated while applying a high voltage to the rotary atomizing head, and in this state, a conductive liquid paint is supplied to the rotary atomizing head. As a result, the liquid paint is charged and atomized, and sprayed from the leading edge of the rotary atomizing head to perform electrostatic coating.

  In the above electrostatic coating apparatus, the diameter of the coating pattern of the paint sprayed from the rotary atomizing head hardly changes. For this reason, when the shape of the object to be coated is complicated, there are cases where the paint cannot be reliably applied to the object to be coated.

  Therefore, a method has been proposed in which a plurality of air holes and air slits formed in an arc shape are provided symmetrically with respect to the rotation axis of the rotary atomizing head, and air is ejected from these air holes or air slits (Patent Literature). 1). According to this method, it is supposed that the coating pattern shape of the paint sprayed from the rotary atomizing head can be deformed by the air ejected from the air hole or the air slit.

JP 60-54754 A

  However, in the method of Patent Document 1, the shape of each air hole or each air slit arranged symmetrically with respect to the rotation axis of the rotary atomizing head is the same, and each air hole or each air slit from the air supply source. Since the flow rate of the air supplied to the same was the same, the shape of the coating pattern could only be deformed in a symmetrical manner. For this reason, for example, when the end portion of the object to be coated is painted, overspray occurs, resulting in a decrease in painting efficiency.

  The objective of this invention is providing the electrostatic coating apparatus which can set a coating pattern to a desired shape and can improve coating efficiency.

  The present invention surrounds a rotary atomizing head (for example, a rotary atomizing head 22 described later) that rotates and rotates in a state where a high voltage is applied to atomize the paint, and the rotary atomizing head. An electrostatic spraying device (e.g., an electrostatic coating device 1 described below) comprising an air jetting port (e.g., a first air jetting port 411 and a second air jetting port 421 described later), The air outlet is disposed on the same circumference around the rotation axis (for example, rotation axis X described later) of the rotary atomizing head, and has an area (for example, a first area described later) in the circumferential direction. 410, the second area 420) is divided into a plurality of sections, and the opening area of the air outlet is different for each area.

In this invention, the air jet nozzle was provided on the same circumference centering on the rotating shaft of the rotary atomizing head. Moreover, this air jet nozzle was divided for every area in the circumferential direction, and the air jet nozzle was provided so that an opening area might differ for every such area.
Here, when the flow area of the air supplied to the air outlet is constant and the opening area of the air outlet is increased, the flow velocity of the jetted air is reduced and the paint atomized by the rotary atomizing head The regulation power that regulates the jet angle of is weakened. On the other hand, if the opening area of the air outlet is reduced, the flow rate of the jetted air is increased, and the regulation force is increased.
Therefore, according to the present invention, air can be ejected at different flow velocities for each zone, so that the spray angle of the paint can be regulated with different regulation force for each zone. That is, the paint can be ejected at different ejection angles for each area, and the shape of the coating pattern can be asymmetrically deformed. For this reason, for example, when coating the end of the object to be coated, by applying the area where the application pattern width is narrow toward the outside of the object to be coated, overspray can be suppressed and the coating efficiency can be improved.

  In this case, the air outlet is preferably connected to individual air supply means (for example, a first air supply unit 51 and a second air supply unit 52 described later) for each of the areas.

In the present invention, the air ejection port is connected to an individual air supply means for each circumferential area so that air is supplied for each area.
Here, if the flow rate of the air ejected from the air ejection port is increased, the regulating force for regulating the ejection angle of the paint atomized by the rotary atomizing head becomes stronger. On the other hand, when the flow rate of the air ejected from the air ejection port is reduced, the regulation force is weakened.
Therefore, according to the present invention, since air can be ejected at a different flow rate for each zone, the spray angle of the paint can be regulated with a different regulation force for each zone. That is, the paint can be ejected at different ejection angles for each area, and the shape of the coating pattern can be asymmetrically deformed. In particular, the shape of the coating pattern is further deformed asymmetrically by reducing the amount of air supplied to an air outlet having a large opening area and increasing the amount of air supplied to an air outlet having a small opening area. be able to. For this reason, for example, when painting the edge of an object to be coated, the overspray can be further suppressed by coating the area where the coating pattern width is narrow toward the outside of the object to be coated, further improving the painting efficiency. it can.
Also, when painting general parts other than the edges of the object to be coated, the amount of air supplied to the air outlet having a large opening area is increased and the air supply to the air outlet having a small opening area is supplied. By reducing the amount, the shape of the coating pattern can be deformed into a symmetrical circular shape, and coating can be performed efficiently.

  ADVANTAGE OF THE INVENTION According to this invention, an electrostatic coating apparatus which can set a coating pattern to a desired shape and can improve coating efficiency can be provided.

It is a perspective view which shows schematic structure of the electrostatic coating apparatus which concerns on one Embodiment of this invention. It is a side view of the electrostatic coating apparatus which concerns on the said embodiment. It is sectional drawing of the front-end | tip part of the electrostatic coating apparatus which concerns on the said embodiment, and a schematic block diagram of an air supply part. It is a top view when an air cap is seen from the front end side. It is a figure which shows the relationship between an application pattern width | variety and a coating-film thickness. It is a figure which shows the relationship between the opening area of an air jet nozzle, and a coating pattern width. It is a figure which shows the relationship between an application pattern width | variety and a coating-film thickness. It is a figure which shows the relationship between the opening area of an air jet nozzle, and a coating pattern width. It is a figure which shows the application pattern of an Example and a comparative example.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
FIG. 1 is a perspective view showing a schematic configuration of an electrostatic coating apparatus 1 according to an embodiment of the present invention. FIG. 2 is a side view of the electrostatic coating apparatus 1.
The electrostatic coating apparatus 1 electrostatically coats a body 2 of an automobile, and has a cylindrical body portion 10 attached to the tip of a robot arm 3, and a substantially U-shape with a bent tip portion. A head portion 20 detachably provided at the tip of the body portion 10.

FIG. 3 is a cross-sectional view of the tip portion of the head unit 20 and a schematic configuration diagram of the air supply unit 50.
The head unit 20 includes an air motor (not shown), a rotary atomizing head 22 that is rotationally driven by the air motor, a paint supply unit (not shown) that supplies paint to the rotary atomizing head 22, and air surrounding the rotary atomizing head 22. The cap 40 and the housing 25 which accommodates these are provided.

  The rotary atomizing head 22 has a substantially conical shape having an inner diameter that increases toward the distal end side, and is provided at the distal end of the head portion 20. The rotary atomizing head 22 is rotatably provided with the rotation axis X as a rotation axis.

  The air cap 40 has a substantially conical shape whose inner diameter increases toward the distal end side, and is attached to the housing 25. The air cap 40 is formed so as to surround the rotary atomizing head 22, and a front end surface 400 of the air cap 40 is behind the front end edge of the rotary atomizing head 22 with respect to the spray direction of the paint. It is located in the middle of the rotary atomizing head 22.

  The front end surface 400 of the air cap 40 is provided with a plurality of first air ejection holes 41 and a plurality of second air ejection holes 42 formed so as to surround the rotary atomizing head 22. The first air ejection hole 41 is formed with the first air ejection port 411 as an opening, and the second air ejection hole 42 is formed with the second air ejection port 421 as an opening. Air is ejected from the first air outlet 411 and the second air outlet 421 in the counter-rotating direction of the rotary atomizing head 22.

The first air outlet 411 and the second air outlet 421 will be described in detail with reference to FIG.
FIG. 4 is a plan view of the air cap 40 as viewed from the distal end side. As shown in FIG. 4, the front end surface 400 of the air cap 40 has an annular shape, and is arranged on the same circumferential center around the rotation axis X of the rotary atomizing head 22 on the annular front end surface 400. A plurality of first air outlets 411 and second air outlets 421 are provided.

The plurality of first air ejection ports 411 are arranged in a circumferential direction into one semi-annular portion (upper portion in FIG. 4) when the annular tip surface 400 is equally divided by a virtual line Y passing through the rotation axis X. It is arranged at equal intervals. The plurality of first air outlets 411 form a first area 410.
The plurality of second air outlets 421 are arranged at equal intervals in the circumferential direction in the other semi-annular part (the lower part in FIG. 4). The plurality of second air outlets 421 form a second area 420.

  The diameter of the first air outlet 411 in the first section 410 and the diameter of the second air outlet 421 in the second section 420 are set to different sizes. Specifically, the diameter of the second air outlet 421 is set to 1.50 C, which is 1.50 times the diameter C of the first air outlet 411. Therefore, the opening area of the second air outlet 421 in the second section 420 is set larger than that of the first air outlet 411 in the first section 410.

The first air ejection hole 41 and the second air ejection hole 42 are both in the circumferential direction, specifically, in the counter-rotation direction opposite to the rotation direction of the rotary atomizing head 22 (direction of arrow R in FIG. 4). Inclined. That is, the first air ejection hole 41 and the second air ejection hole 42 are provided so as to be inclined in the counter-rotating direction of the rotary atomizing head 22 from the proximal end side to the distal end side of the head portion 20.
Moreover, the inclination angle of the anti-rotation direction of the 1st air ejection hole 41 and the inclination angle of the anti-rotation direction of the 2nd air ejection hole 42 are set to the same magnitude | size. The inclination angle in the counter-rotation direction represents a twist angle of air ejected from the air ejection port with respect to the rotation axis X, and is appropriately set to a desired angle.

The first air ejection holes 41 and the second air ejection holes 42 are both inclined in the radial direction, specifically, inward in the radial direction. That is, the first air ejection hole 41 and the second air ejection hole 42 are provided so as to be inclined radially inward from the proximal end side to the distal end side of the head portion 20.
Further, the radial inclination angle of the first air ejection hole 41 and the radial inclination angle of the second air ejection hole 42 are set to the same size. This radial inclination angle is appropriately set so that air is ejected toward the vicinity of the tip edge of the rotary atomizing head 22 according to the position of the air outlet and the circumferential inclination angle of the air ejection hole. Is done.

Returning to FIG. 3, a plurality of first air passages 412 communicating with the first air ejection holes 41 and a plurality of second air passages 422 communicating with the second air ejection holes 42 are provided inside the air cap 40. It has been.
The first air passage 412 is connected to a first air supply unit 51 described later, and air is supplied from the first air supply unit 51.
The second air passage 422 is connected to a second air supply unit 52 described later, and air is supplied from the second air supply unit 52.

The air supply unit 50 includes a first air supply unit 51, a second air supply unit 52, and an air compressor 53 as an air supply source.
The first air supply unit 51 supplies air having a predetermined flow rate compressed by the air compressor 53 to the first air passage 412 communicating with the air ejection hole 41.
The second air supply unit 52 supplies air of a predetermined flow rate compressed by the air compressor 53 to the second air passage 422 communicating with the air ejection hole 42.

The first air supply unit 51 includes a first air valve 511, a first air flow meter 512, and a first air control unit (CU) 513.
The first air valve 511 is an air valve that is driven by air pressure, and is electrically connected to the first air control unit 513 via an electropneumatic converter (not shown).
The first air flow meter 512 is electrically connected to the first air control unit 513. The first air flow meter 512 detects the flow rate of air supplied to the first air passage 412 and outputs a detection signal to the first air control unit 513.
The first air control unit 513 controls the opening degree of the first air valve 511 based on the air flow rate detected by the first air flow meter 512.

  The first air control unit 513 outputs an electrical signal to an electropneumatic converter (not shown). This electric signal is converted into an air pressure signal by the electropneumatic converter and output to the first air valve 511. Thereby, the opening degree of the first air valve 511 is accurately controlled, and the flow rate of the air supplied to the first air passage 412 is accurately controlled.

The second air supply unit 52 includes a second air valve 521, a second air flow meter 522, and a second air control unit (CU) 523.
The second air valve 521 is an air valve driven by air pressure, and is electrically connected to the second air control unit 523 via an electropneumatic converter (not shown).
The second air flow meter 522 is electrically connected to the second air control unit 523. The second air flow meter 522 detects the flow rate of the air supplied to the second air passage 422 and outputs the detection signal to the second air control unit 523.
The second air control unit 523 controls the opening degree of the second air valve 521 based on the air flow rate detected by the second air flow meter 522.

  The second air control unit 523 outputs an electrical signal to an electropneumatic converter (not shown). This electric signal is converted into a pneumatic signal by an electropneumatic converter and output to the second air valve 521. Thereby, the opening degree of the second air valve 521 is accurately controlled, and the flow rate of the air supplied to the second air passage 422 is accurately controlled.

When air is supplied from the first air supply unit 51 to the first air passage 412, the supplied air passes from the first air outlet 411 to the vicinity of the leading edge of the rotary atomizing head 22 through the first air ejection hole 41. It is ejected toward the so-called shaping air. This shaping air deforms the flight pattern of paint sprayed from the tip edge of the rotary atomizing head 22, that is, the paint application pattern.
Similarly, when air is supplied from the second air supply unit 52 to the second air passage 422, the supplied air passes through the second air ejection holes 42 from the second air ejection port 421 to the tip of the rotary atomizing head 22. It is ejected toward the edge and becomes shaping air. This shaping air deforms the flight pattern of paint sprayed from the tip edge of the rotary atomizing head 22, that is, the paint application pattern.

Next, operation | movement of the electrostatic coating apparatus 1 which concerns on this embodiment is demonstrated.
First, air is supplied from the air compressor 53 to an air motor (not shown) to rotate the rotary atomizing head 22 at a high speed. Further, a current from a power source (not shown) is boosted, and a high voltage current is applied to the rotary atomizing head 22.

  Next, the paint is supplied to the rotary atomizing head 22 from a paint supply unit (not shown). Then, paint is discharged to the inner peripheral surface of the rotary atomizing head 22, and the discharged paint is charged by applying a high voltage, and is atomized by the centrifugal force of the rotary atomizing head 22. Is sprayed on the object to be coated.

  Simultaneously with the spraying of the paint, air is supplied from the first air supply part 51 to the first air ejection hole 41 via the first air passage 412, and from the second air supply part 52 via the second air passage 422. Air is supplied to the second air ejection holes 42. Then, shaping air is ejected from the first air ejection port 411 and the second air ejection port 421 toward the tip edge of the rotary atomizing head 22.

  At this time, the air ejected from the first air ejection port 411 and the air ejected from the second air ejection port 421 have the same twist angle with respect to the rotation axis X and the rotation direction of the rotary atomizing head 22. Are ejected in the opposite counter-rotation direction. The air ejected in the counter-rotating direction collides with the paint sprayed from the tip edge of the rotary atomizing head 22, thereby promoting the atomization of the paint.

  Further, the flow rate of air supplied to the first air jet port 411 and the flow rate of air supplied to the second air jet port 421 are individually controlled. When the flow rate of air supplied to the first air jet port 411 and the flow rate of air supplied to the second air jet port 421 are set to be the same, the air jetted from the first air jet port 411 having a small opening area is The air is ejected with a larger flow velocity than the air ejected from the second air ejection port 421 having a large opening area. Thereby, the flight pattern of the paint sprayed from the front end edge of the rotary atomizing head 22, that is, the coating pattern of the paint is deformed asymmetrically.

In particular, when the flow rate of air supplied to the first air jet 411 having a small opening area is increased and the flow rate of air supplied to the second air jet 421 having a large opening area is set small, the coating pattern is deformed more asymmetrically. Is done.
As described above, electrostatic coating is performed.

Next, the relationship between the opening area of the air outlet and the coating pattern width will be described with reference to FIGS. In addition, below, it demonstrates using the aperture diameter of an air ejection port instead of the opening area of an air ejection port.
FIG. 5 shows the relationship between the coating pattern width and the coating thickness when the diameter C of the air outlet is changed stepwise from 1.25 times 1.25 C and 1.50 times 1.50 C. FIG. The data in FIG. 5 is experimental data when the rotational speed of the rotary atomizing head is 30000 rpm and the flow rate of the air supplied to the air outlet is 700 NL / min. In FIG. 5, the area | region of application pattern width 0mm means the area | region on the extension line of the rotating shaft of a rotary atomization head.

As shown in FIG. 5, it can be seen that the coating thickness is thick in the region where the coating pattern width is narrow and thin in the region where the coating pattern width is wide. Moreover, in this experiment, since the aperture diameter of all the air jet nozzles was set to the same aperture diameter, the coating pattern is positively symmetric, and FIG. 5 is close to a normal distribution.
Here, a region from the maximum value of the coating film thickness to ½ of the maximum value is defined as a coating pattern, and the width dimension at this time is defined as a coating pattern width.

FIG. 6 is a diagram showing the relationship between the coating pattern width defined as described above and the diameter of the air jet outlet based on the data of FIG.
As shown in FIG. 6, it can be seen that the coating pattern width increases as the diameter of the air outlet increases. Therefore, it can be seen that the coating pattern width can be adjusted by adjusting the diameter and the opening area of the air ejection port based on this result. That is, it can be seen that the coating pattern width can be asymmetrically changed by making the opening area of the air jetting port different for each area in the circumferential direction.

  Moreover, FIG. 7 is a figure which shows the relationship between the coating pattern width | variety and coating-film thickness when the aperture diameter C of an air jet nozzle is set to 1.50C of 1.50 times. The data in FIG. 7 is experimental data when the rotational speed of the rotary atomizing head is 50000 rpm and the flow rate of the air supplied to the air outlet is 600 NL / min. Similarly to FIG. 5, the region with a coating pattern width of 0 mm in FIG. 7 means a region on an extension line of the rotation axis of the rotary atomizing head.

  As shown in FIG. 7, it can be seen that the coating thickness is thick in the region where the coating pattern width is narrow and thin in the region where the coating pattern width is wide. Moreover, in this experiment, since the diameter of all the air jet nozzles was set to the same diameter, the coating pattern is positively symmetric, and FIG. 7 is close to a normal distribution as in FIG.

FIG. 8 is a diagram showing the relationship between the coating pattern width defined as described above and the diameter of the air jet outlet based on the data of FIG.
As shown in FIG. 8, it can be seen that by setting the diameter of the air outlet to 1.50 times, the coating pattern width is widened, and this result is consistent with the result shown in FIG. Therefore, from these results, the coating pattern width is deformed asymmetrically by making the opening area of the air outlet different for each circumferential area regardless of the rotational speed of the rotary atomizing head and the air supply amount. I understand that I can do it.

According to the electrostatic coating apparatus 1 according to the present embodiment, the following effects are exhibited.
(1) In the present embodiment, the first air outlet 411 and the second air outlet 421 are provided on the same circumference around the rotation axis X of the rotary atomizing head 22. Further, these air outlets are divided into a first area 410 and a second area 420 in the circumferential direction, and an opening area of the first air outlet 411 that forms the first area 410 and a second area 420 are formed. The opening area of the second air ejection port 421 is different from that of the second air ejection port 421.
Here, when the flow area of the air supplied to the air outlet is constant, if the opening area of the air outlet is increased, the flow velocity of the jetted air is reduced and atomized by the rotary atomizing head 22. The regulation power that regulates the spray angle of paint is weakened. On the other hand, if the opening area of the air outlet is reduced, the flow rate of the jetted air is increased, and the regulation force is increased.
Therefore, according to the present embodiment, air can be ejected at different flow velocities for each zone, so that the spray angle of the paint can be regulated with different regulation force for each zone. That is, the paint can be ejected at different ejection angles for each area, and the shape of the coating pattern can be asymmetrically deformed. For this reason, for example, when coating the end of the object to be coated, by applying the area where the application pattern width is narrow toward the outside of the object to be coated, overspray can be suppressed and the coating efficiency can be improved.

(2) Further, in the present embodiment, the first air supply unit 51 is connected to the first air outlet 411 that forms the first section 410, and the second air outlet 421 that forms the second section 420 is connected to the second air outlet 421. The air supply unit 52 is connected so that the air supply amount can be controlled for each zone.
Here, when the flow rate of the air ejected from the air ejection port is increased, the regulating force for regulating the ejection angle of the paint atomized by the rotary atomizing head 22 becomes stronger. On the other hand, when the flow rate of the air ejected from the air ejection port is reduced, the regulation force is weakened.
Therefore, according to this embodiment, since air can be ejected at a different flow rate for each zone, the spray angle of the paint can be regulated with a different regulation force for each zone. That is, the paint can be ejected at different ejection angles for each area, and the shape of the coating pattern can be asymmetrically deformed. In particular, the shape of the coating pattern is reduced by reducing the amount of air supplied to the second air outlet 421 having a large opening area and increasing the amount of air supplied to the first air outlet 411 having a small opening area. Can be further asymmetrically deformed. For this reason, for example, when painting the edge of an object to be coated, the overspray can be further suppressed by coating the area where the coating pattern width is narrow toward the outside of the object to be coated, further improving the painting efficiency. it can.

  In addition, when painting a general portion other than the end portion of the object to be coated, the amount of air supplied to the second air jet port 421 having a large opening area is increased and the first air jet port 411 having a small opening area. On the other hand, by reducing the supply amount of air, the shape of the coating pattern can be changed into a symmetrical circular shape, and the coating can be performed efficiently.

  It should be noted that the present invention is not limited to the above-described embodiment, and modifications and improvements within the scope that can achieve the object of the present invention are included in the present invention.

  For example, in the above embodiment, the two areas of the first area 410 and the second area 420 are provided, but the present invention is not limited to this. Specifically, a third air outlet and a third air outlet having different opening areas from the first air outlet 411 and the second air outlet 421 are provided, and a third area formed from the third air outlet. A fourth area formed from the fourth air outlet may be provided.

  Moreover, in the said embodiment, although the 1st air ejection hole 41 and the 2nd air ejection hole 42 were inclined in the anti-rotation direction of the rotary atomization head 22, it is not limited to this. These air ejection holes may be inclined in the rotational direction of the rotary atomizing head 22.

  Moreover, in the said embodiment, although the 1st air ejection hole 41 and the 2nd air ejection hole 42 were inclined inward in radial direction, it is not limited to this. For example, these air ejection holes may be inclined radially outward.

  Next, the present invention will be described in more detail based on examples, but the present invention is not limited thereto. Note that the coating pattern width in this example was based on the above-described definition.

[Example 1 and Comparative Examples 1-2]
Using the electrostatic coating apparatus 1 according to the above embodiment, the amount of air supplied to the first air outlet 411 (caliber C) and the amount of air supplied to the second air outlet 421 (diameter 1.50C) Was set to 600 NL / min, and electrostatic coating was performed. The coating pattern width at this time was measured, and this was designated as Example 1.

  Electrostatic coating is performed using an electrostatic coating device having the same configuration as that of the electrostatic coating device 1 except that the air jet port is configured by only an air outlet having a diameter C, and the air supply amount is set to 600 NL / min. did. The coating pattern width at this time was measured, and this was designated as Comparative Example 1.

  An electrostatic coating apparatus having the same configuration as that of the electrostatic coating apparatus 1 is used except that the air outlet is configured by only an air outlet having a diameter of 1.50 C, and the electrostatic supply is set at 600 NL / min. Carried out. The coating pattern width at this time was measured, and this was designated as Comparative Example 2.

The application pattern of Example 1 is shown in FIG. 9A, and the application patterns of Comparative Example 1 and Comparative Example 2 are shown in FIGS. 9B and 9C.
Comparing Comparative Example 1 and Comparative Example 2, the coating pattern of Comparative Example 1 was a circle having a diameter of approximately 300 mm, whereas the coating pattern of Comparative Example 2 was a circle having a diameter of approximately 470 mm. From this result, it was found that, when the air supply amount is constant, the coating pattern width is increased as the diameter of the air ejection port is increased.

  Moreover, the coating pattern of Example 1 was an asymmetrical coating pattern formed by combining the coating pattern of Comparative Example 1 and the coating pattern of Comparative Example 2. From this result, it was confirmed that according to the electrostatic coating apparatus 1 configured so that the diameter of the air jet port is different for each area, an asymmetric coating pattern can be formed.

[Example 2 and Comparative Examples 3 to 4]
Using the electrostatic coating apparatus 1 according to the above embodiment, the amount of air supplied to the first air jet 411 (caliber C) is set to 700 NL / min, and the second air jet 421 (caliber 1.50 C) is set. The air supply amount was set to 200 NL / min, and electrostatic coating was performed. The coating pattern width at this time was measured, and this was designated as Example 2.

  Using the electrostatic coating apparatus used in Comparative Example 1, electrostatic coating was performed with the air supply rate set to 700 NL / min. The coating pattern width at this time was measured, and this was designated as Comparative Example 3.

  Using the electrostatic coating apparatus used in Comparative Example 1, electrostatic coating was performed with the air supply rate set to 400 NL / min. The coating pattern width at this time was measured, and this was designated as Comparative Example 4.

The application pattern of Example 2 is shown in FIG. 9 (d), and the application patterns of Comparative Example 3 and Comparative Example 4 are shown in FIGS. 9 (e) and 9 (f).
Comparing Comparative Example 3 and Comparative Example 4 with Comparative Example 1 above, the coating pattern width in Comparative Example 3 in which the air supply amount was larger than that in Comparative Example 1 was the same even though the same electrostatic coating apparatus was used. On the other hand, it was confirmed that the width of the coating pattern was widened in Comparative Example 4 in which the air supply amount was smaller than that in Comparative Example 1, although it was narrower.

Further, when Example 2 is compared with Example 1 described above, the amount of air supplied to the first air outlet 411 having a small diameter is increased in spite of using the same electrostatic coating apparatus. In Example 2, in which the amount of air supplied to the second air jet port 421 having a large size was reduced, it was confirmed that the shape of the coating pattern was further deformed asymmetrically compared to Example 1.
From these results, it was confirmed that the coating pattern shape can be further asymmetrically changed by changing the air supply amount for each zone.

DESCRIPTION OF SYMBOLS 1 ... Electrostatic coating apparatus 22 ... Rotary atomization head 41 ... 1st air ejection hole 42 ... 2nd air ejection hole 51 ... 1st air supply part (air supply means)
52 ... Second air supply section (air supply means)
410 ... 1st area (area)
420 ... 2nd area (area)
411: First air outlet (air outlet)
421 ... Second air outlet (air outlet)

Claims (2)

A rotating atomizing head that charges and atomizes the paint by rotating in a state where a high voltage is applied,
An electrostatic spraying device comprising an air outlet formed around the rotary atomizing head,
The air jets are arranged on the same circumference centered on the rotation axis of the rotary atomizing head, and a plurality of air jets are arranged for each zone in the circumferential direction.
The electrostatic coating apparatus, wherein an opening area of the air outlet is different for each of the areas. The electrostatic coating apparatus according to claim 1,
The electrostatic spraying apparatus, wherein the air ejection port is connected to an individual air supply means for each of the areas.

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