JP5887248B2 - Painting gun - Google Patents

Description

  The present invention relates to a coating gun capable of expanding a control range of an application pattern.

  If the control range of the coating pattern is wide, one coating gun can be used for many applications. Therefore, a coating gun capable of expanding the control range of the coating pattern has been proposed (see, for example, Patent Document 1 (FIG. 3)).

  As shown in FIG. 3 of Patent Document 1, the rotary atomizing electrostatic coating apparatus (10) (the numbers in parentheses indicate the symbols described in Patent Document 1. The same applies hereinafter) with respect to the rotation center axis. A first air outlet (23) for injecting the shaping air A in the twisting direction and a second air outlet (24) for injecting the shaping air B in a direction parallel to the rotation center axis are provided. And in paragraph number [0020] of Patent Document 1, there is a description that “... a fine coating pattern width can be selected by appropriately setting the pressures of the shaping air A and B.”. is there.

If the hole diameter of the air outlets (23, 24) is constant, the square root of the pressure is proportional to the velocity (form of flow continuity). The flow rate is proportional to the speed.
That is, when the pressure is controlled according to Patent Document 1, the flow rate of the shaping air changes.

  The present inventors conducted an experiment to measure a change in luminance by changing the flow rate of shaping air. That is, the brightness was measured by changing only the flow rate of the shaping air with the same paint gun without changing the type and flow rate of the paint. The results are shown in the following table.

  In contrast to Experiment 101, in Experiment 102, the brightness changed by 1.6% when the amount of shaping air was increased by 17%. This amount of change (change ratio) is not a small value in the paint color.

That is, as a result of studies by the present inventors, it has been found that when the flow rate of shaping air is changed, the luminance of the object to be coated changes. It is not preferable that the luminance changes during painting.
Therefore, there is a need for a coating technique that can change the coating pattern while suppressing changes in luminance.

Japanese Patent Laid-Open No. 7-24367

  This invention makes it a subject to provide the coating gun which can change an application | coating pattern, suppressing the change of a brightness | luminance.

The invention according to claim 1 is a coating gun comprising a rotary atomizing head and a shaping ring surrounding the rotary atomizing head, wherein the shaping air has a shaping air ejection hole so that the shaping air becomes a swirling flow. Is provided to be inclined with respect to the rotation center axis of the rotary atomizing head, and includes a first rotation means for rotating the rotary atomization head, and a second rotation for rotating the shaping ring around the rotation center axis In order to make the coating ring have a larger diameter compared to the non-rotating state independently of the rotary atomizing head, the shaping ring is provided in a direction opposite to the inclination direction of the shaping air ejection hole, Further, in order to make the coating pattern have a smaller diameter compared with the non-rotating state, the coating pattern can be rotated in the same direction as the inclination direction of the shaping air ejection hole .

In the invention according to claim 1, not only the rotary atomizing head but also the shaping ring is rotated.
Shaping air is blown out in the form of a swirling flow from a non-rotating shaping ring.

When the shaping ring is rotated in the direction opposite to the inclination direction of the shaping air ejection hole, the shaping air collides with the atmosphere and is inclined more greatly. As a result, the coating pattern has a larger diameter than when not rotating.
Further, when the shaping ring is rotated in the same direction as the inclination direction of the shaping air ejection hole, the shaping air collides with the atmosphere and the inclination angle becomes small. As a result, the coating pattern has a smaller diameter than when not rotating.

  In addition, since the shaping air is constant, there is almost no fear that the luminance will change. Therefore, according to this invention, the coating gun which can change an application | coating pattern is provided, suppressing the change of a brightness | luminance.

It is sectional drawing of the coating gun which concerns on this invention. FIG. 2 is an enlarged view of part 2 of FIG. 1. It is an action figure of a painting gun.

  Embodiments of the present invention will be described below with reference to the accompanying drawings. The drawings are viewed in the direction of the reference numerals.

  As shown in FIG. 1, a coating gun 10 includes a cylindrical gun body 11, a shaping ring 13 that is rotatably supported by a front portion of the gun body 11 via a bearing 12, a gun body 11, and a shaping ring. 13, a hollow rotary shaft 15 rotatably supported via bearings 14, 14, a rotary atomizing head 17 attached to the tip of the hollow rotary shaft 15 and surrounded by a shaping ring 13, A coating material supply path 18 extending through the inside to the back of the rotary atomizing head 17, a first rotating means 20 for rotating the rotary atomizing head 17 via the hollow rotary shaft 15, and a second rotating means for rotating the shaping ring 13 30.

  The first rotating means 20 is, for example, a first servo motor 21, a first drive gear 22 attached to the motor shaft of the first servo motor 21, meshed with the first drive gear 22, and fixed to the hollow rotary shaft 15. And a first driven gear 23.

  The second rotating means 30 is, for example, connected to a second servo motor 31 and a motor shaft of the second servo motor 31 via a coupling 32, and is rotatably supported by the gun body 11 via bearings 33 and 33. A transmission shaft 34, a second drive gear 35 attached to the tip of the transmission shaft 34, and a second driven gear 36 that meshes with the second drive gear 35 and is provided at or formed at the base of the shaping ring 13. Consists of.

A paint pipe 38 is connected to the paint supply path 18 to supply paint.
The gun body 11 has a hollow portion 39, and an air pipe 41 is connected to the hollow portion 39 and pressurized air is supplied thereto. However, since the gun body 11 is a non-rotating member and the shaping ring 13 supported by the gun body 11 is a rotating member, it is necessary to devise a structure between both members.

As shown in FIG. 2, an air outflow hole 43 is formed in the gun body 11 at a position of a radius R from the rotation center shaft 42. Similarly, an air receiving hole 44 is formed in the shaping ring 13 at a position of a radius R from the rotation center shaft 42.
A small-diameter seal ring 46 having a radius smaller than the radius R and a large-diameter seal ring 47 having a radius larger than the radius R are prepared in the gun body 11.

  The small diameter seal ring 46 is disposed inside the air outflow hole 43 and the large diameter seal ring 47 is disposed outside the air outflow hole 43 so that the small diameter seal ring 46 and the large diameter seal ring 47 are connected to the gun body 11. Fit into. Then, the small diameter seal ring 46 and the large diameter seal ring 47 are compressed by the shaping ring 13.

  The air outflow hole 43 is stationary, and the air receiving hole 44 moves in the direction of the front and back of the drawing. However, since air leakage is prevented by the small diameter seal ring 46 and the large diameter seal ring 47, the air discharged from the air outflow hole 43 All flow into the air receiving hole 44. The small-diameter seal ring 46 and the large-diameter seal ring 47 are preferably O-rings that are inexpensive and readily available, but may be oil seals or other seal materials.

The operation of the paint gun described above will be described next.
As shown in FIG. 3A, the shaping ring 13 is provided with a shaping air ejection hole 48 that is inclined with respect to the rotation center axis 42 of the rotary atomizing head so that the shaping air turns into a swirling flow. ing. The inclination angle at this time is θ1.

As shown in (b), the shaping ring 13 is rotated in the direction opposite to the inclination direction.
That is, when the shaping ring 13 is rotated in the direction opposite to the inclination direction of the shaping air ejection hole 48, the shaping air collides with the atmosphere and is inclined more greatly. The inclination angle θ2 is larger than θ1. As a result, the coating pattern has a large diameter compared to (a) (when not rotating).
The coating pattern can be changed continuously by controlling the rotation speed.

  In this example, the inclination angle θ1 in non-rotating FIG. 3A is 40 °. When rotated, the inclination angle θ2 in FIG. 3B was about 50 °.

Then, the brightness | luminance of the to-be-coated object in the case where an inclination angle is 40 degrees and 50 degrees was investigated.
○ Experiments 01 and 02:
The type of paint and the flow rate of the paint were the same, the flow rate of shaping air was the same, the inclination angles were 40 ° and 50 °, and the luminance was measured.
○ Experiments 03 and 04:
The type of paint and the flow rate of paint were the same, the flow rate of shaping air was increased by 17% relative to Experiments 01 and 02, and the inclination angle was set to 40 ° and 50 °, and the luminance was measured.
The measurement results are shown in the following table.

  The brightness in Experiment 01 and Experiment 02 was 0.24% different. Since the difference shown in Table 1 in the prior art was 1.6%, the luminance difference was greatly suppressed to 1/8 according to the present invention.

Further, there was a difference of 0.16% in the luminance between Experiment 03 and Experiment 04. Since the difference shown in Table 1 in the prior art is 1.6%, the luminance difference is further suppressed to 1/10 by the present invention.
Note that the amount of change in the size of the coating pattern in Experiments 101 and 102 shown in Table 1 is the same as the amount of change in the size of the coating pattern in Experiments 03 and 04.

  Therefore, it is recommended to change the inclination angle while keeping the flow rate of the shaping air constant. Furthermore, it is recommended to change the inclination angle according to the rotational speed of the shaping ring.

  The present invention is suitable for a coating gun that requires diversification of coating patterns.

  DESCRIPTION OF SYMBOLS 10 ... Paint gun, 11 ... Gun body, 13 ... Shaping ring, 17 ... Rotating atomizing head, 20 ... First rotating means, 30 ... Second rotating means, 42 ... Rotation center axis, 48 ... Shaping air ejection hole, [theta] 1 ... tilt angle.

Claims (1)

In a paint gun comprising a rotary atomizing head and a shaping ring surrounding the rotary atomizing head,
The shaping ring is provided with a shaping air ejection hole that is inclined with respect to the rotation center axis of the rotary atomizing head so that the shaping air becomes a swirling flow,
First rotating means for turning the rotary atomizing head is provided, and second rotating means for turning the shaping ring around the rotation center axis is provided,
In order to increase the diameter of the coating ring independently of the rotary atomizing head as compared with the non-rotating state, the shaping ring is in a direction opposite to the inclination direction of the shaping air ejection hole, and when not rotating. In order to make the coating pattern small in comparison, the coating gun is configured so that it can be rotated in the same direction as the inclination direction of the shaping air ejection hole .

Images