JPH0523251Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a coating device, and more specifically, the present invention relates to a coating device, and more specifically, a coating gun that constitutes an automatic coating device installed in an automatic coating line in a factory is provided in a swingable manner. The present invention relates to a coating device that makes it possible to coat a workpiece with a uniform paint film thickness by installing the painting gun with its center point near the tip of the painting gun or close to the workpiece side.

[Background of the invention] In recent years, in the automobile industry, there has been an increasing demand for improved productivity of automobiles, and more advanced automation of line production processes is progressing. In this line production process, in addition to assembly lines that assemble parts, automatic painting lines have been developed that paint automobile bodies without human intervention.

In a painting device that is installed in such an automatic painting line and sprays paint onto the body of a car that is transported via an automatic conveyance device, a paint gun is used to spray paint onto the body of a car that moves at a predetermined speed in a fixed direction relative to the painting device. It is customary to be displaceably attached so that the area to be coated can be coated in one step.

For example, the technical concept of making the paint gun rotatable or swingable is disclosed in Japanese Utility Model Application Publication No. 56-154866.
It is widely known as shown in Japanese Patent Application Laid-Open No. 58-110585.

FIG. 1 shows an example of a conventional painting gun that is swingably constructed. That is, the painting gun 2 is connected to an arm 4 connected to a painting device (not shown).
The other end of the gun support bar 6 is attached via a pin 5 to one end of a swingable gun support bar 6, and the other end of the gun support bar 6 is rotated in the direction of the arrow via a crank mechanism or the like under the driving action of a rotational drive source (not shown). It is connected via a reciprocating rod 8 and a pin 10. Therefore, as the rod 8 is linearly displaced, the coating gun 2 is configured to be swingable in the direction of arrow A. In this case, the pivot point is set at the rear of the body of the painting gun 2, but as shown in FIG. 2b, it is also known that the pivot point is set at the center of the body of the painting gun 2 ( (Refer to Utility Model Application Publication No. 56-154866).

Therefore, as shown in Figure 2 a and b, the workpiece 1
The painting gun 2 is placed at a predetermined distance from the painting gun 2.
is positioned, and the paint is sprayed while being oscillated at a constant oscillation angle to form a paint film on the surface of the work 12.

However, in this case, the rotation of the rotary drive source is converted into linear motion via a crank mechanism, etc., and is oscillated via the rod 8 etc. that is converted into linear motion, so that the painting gun is substantially When considering the motion of 2 projected onto the surface of the workpiece 12, the motion approximately approximates simple harmonic motion. Therefore, since the speed of the painting gun 2 at the turning position P is almost close to 0 compared to the speed at the intermediate point, the paint sprayed at the turning position P is slightly thicker along the edge of the sprayed part on the workpiece 12. A paint film will be formed.

Generally, when painting the body of an automobile, electrostatic painting is used. In this electrostatic coating, metal-based paint that is charged by applying a high voltage is sprayed onto the workpiece, so unevenness in the paint film affects its appearance and causes coating defects.
In order to avoid such local non-uniformity of the paint film, it is conceivable to move the paint gun some distance from the workpiece. However, since the distance at which the painting gun is separated from the workpiece is regulated within a predetermined range, if the distance is too far, the paint will be scattered around, making it impossible to achieve the desired painting effect. It is also possible to increase the swing angle of the painting gun, but as can be understood from Fig. 2, if the swing center is at the rear of the paint gun, selecting too large a swing angle will cause the same problem. paint is scattered all over the place. Therefore, a technical challenge in automatic painting is to form a paint film as uniform as possible.

[Purpose of the invention] The present invention was made in order to overcome the above-mentioned disadvantages, and the purpose of the present invention is to set the pivot point of the painting gun, which is swingably attached to the arm on which the painting gun is supported, to By setting the gun near the tip or on the workpiece side and selecting the swinging angle as large as possible, the thickness of the paint film formed on the workpiece during painting can be made uniform, resulting in high-quality painting. The purpose of the present invention is to provide a coating device that can perform coating on a workpiece.

[Means for Achieving the Object] In order to achieve the above-mentioned object, the present invention includes a coating gun that sprays paint onto an object to be coated, and a swinging mechanism that swings and displaces the coating gun. The swinging mechanism includes: a support arm fixed to the main body side; a slide arm supported by the main body and reciprocating under the driving action of a drive source; and a swinging mechanism between the support arm and the slide arm. and a pivotally supported coating gun support member, wherein the pivot portion on the support arm side of the coating gun support member is provided closer to the object to be painted than the nozzle tip of the coating gun. shall be.

[Embodiments] Next, preferred embodiments of the coating apparatus according to the present invention will be described in detail with reference to the accompanying drawings.

3, reference numeral 20 denotes an automatic coating apparatus according to the present invention. In this case, the automatic coating apparatus 20 includes a body 22 and a support arm 24 extending horizontally from the body 22. The support arm 24 has a plurality of coating guns 26 arranged at predetermined positions on the support arm 24, spaced apart by a predetermined distance and each of the coating guns 26 is pivotably mounted on the support arm 24.

In this case, the gun support bars 27a to 27d are spaced a predetermined distance from the support arm 24 and one end of each bar is attached to the support arm 24 by pins 28a to 28d so that it can swing freely, and the other end of each bar is connected to a slide arm 30 arranged approximately parallel to the support arm 24 by pins 32a to 32d.

The slide arm 30 is slidably fitted into the guide 34, and one end of the slide arm 30 is connected to a disk 36 which rotates under the driving action of a rotational drive source 35 disposed in the main body 22 via a connecting rod 38. The links are combined. Therefore, the disk 3
6 is converted into a reciprocating linear motion by a crank mechanism constituted by the disk 36 and the connecting rod 38, and the slide arm 30 connected to the connecting rod 38 is guided by the guide 34 as shown in FIG. The middle is reciprocated in the direction of the arrow, and as a result, the gun support bars 27a to 27
Each of the painting guns 26 attached to the support arm 2
4, the pins 28a to 28d are used as the center of the swing movement.

In this case, as seen in FIG. 4a, the painting gun 26 is attached to the holding members 40a to 40
The nozzle 42 attached to the tip of the painting gun 26 is attached to the gun support bars 27a to 27d via the pins 28a to 28d.
d, or as shown in FIG. 4b, a position that is a predetermined distance back from the pins 28a to 28d in the direction opposite to the paint injection direction, in other words, the pins 28a to 28d as the center of swing. 28d is set closer to the object to be coated than the nozzle 42.

Here, the paint gun 26 is a known one used for electrostatic painting, and the metal-based paint sprayed from the nozzle 42 is sprayed from the paint gun 26.
A high voltage is applied within the coating material 6, and the conductive particles in the paint are charged.

The coating apparatus according to this embodiment is basically constructed as described above, and its operation and effects will be explained next.

As shown in FIG. 5, the automatic painting device 20 is arranged so that its support arm 24 is positioned in a direction perpendicular to the direction of conveyance of a vehicle body 52 that is conveyed at a constant speed by a conveyance mechanism 50. . Therefore, the vehicle body 52 moving via the transport mechanism 50
The automatic painting device 20 is driven to perform a predetermined painting operation.

That is, as shown in FIG.
5 to rotate the disk 36, the connecting rod 38 connected to the disk 36 transmits the rotational drive of the disk 36 to the slide arm 30 as a reciprocating linear motion. As a result, the slide arm 30 is guided by the guide 34 and reciprocates in the direction of the arrow in the figure. One end of the slide arm 30 has pins 32a to 3.
The gun support bars 27a to 27d, which are connected to the support arm 24 at the other end via pins 28a to 28d, swing at a predetermined swing angle in a direction perpendicular to the moving direction of the vehicle body 52. Start. Thereafter, the gun support bars 27a to 27d
Paint is sprayed toward the vehicle body 52 from the nozzle 42 of the paint gun 26 attached to the vehicle body 52 to start painting.

In this case, FIG. 6 conceptually shows how the coating pattern of the paint sprayed from the coating gun 26 moves. That is, in the same figure, the pivot point of the painting gun 26 is located at the pins 28a to 28d.
is the center, and these pins 28a to 2
8d indicates the direction from the nozzle 42 of the painting gun 26 to the vehicle body 5.
On the other hand, since the distance between the painting gun 26 and the vehicle body 52 is determined by the painting conditions and is constant, the swinging angle during the swinging motion process during painting is The center point of the swing is larger than that in the case where the center point is located at the rear of the painting gun 26.

Therefore, one rotation of the disk 36 results in one coating pattern of the paint sprayed from the coating gun 26.
While reciprocating, the speed at which the painted surface of the vehicle body 52 is swept increases. Therefore, the speed near the switching position of the rocking motion becomes relatively large, and the thickness of the coating film at the end of the coating pattern at that time is prevented from becoming thicker than at other parts.

Moreover, since the elevation angle seen from the vehicle body 52 side when the painting gun 26 is located at the switching point becomes small, the oval painting pattern 54 at this point
As a result, the edges of the coating pattern 54 extend outward, in other words, the edges of the coating pattern 54 become thinner, and it will be appreciated that the thickness of the coating film in this vicinity is reliably prevented from increasing.
Therefore, in electrostatic painting, the paint film formed on the surface of the vehicle body 52 is uniform, and therefore, a uniform and aesthetically pleasing painting job is achieved without the occurrence of striped and relatively thick paint defects. It becomes possible to carry out the following.

[Effects of the invention] As described above, according to the invention, since the pivot point of the painting gun that can swing freely relative to the workpiece is placed close to the workpiece side from the tip of the painting gun, the painting This has the advantage that thickening of the paint film at the edges of the pattern can be prevented and uniform and even paint can be applied. In addition, for example, there is no need for a mechanism to turn on and off the paint sprayed from the paint gun at the point of switching the position of the paint gun in the painting process, and the mechanism of the painting equipment itself can be made more compact. It is something to play.

[Brief explanation of the drawing]

Fig. 1 is a partially omitted side view showing the swing mechanism of a coating gun according to the prior art, Fig. 2 is a conceptual diagram of the coating process according to the prior art, and Fig. 3 shows the configuration of an automatic coating device according to the present invention. A perspective view to explain, FIG. 4 is an enlarged explanatory view of the main part in FIG. 3, FIG. 5 is a diagram showing the arrangement of a painting line to which the automatic painting device is applied, and FIG. 6 is a painting diagram of the painting device according to the present invention. It is a figure explaining the effect|action in a process. 20... Automatic painting device, 24... Support arm,
26...Painting gun, 27a-27d...Gun support bar, 28a-28d...Pin, 30...Slide arm, 34...Guide, 35...Rotary drive source, 36...Disc, 38...Connecting Rod, 50...transport mechanism, 52...vehicle body.

Claims (1)

[Claims for Utility Model Registration] A coating gun that sprays paint onto an object to be coated, and a swinging mechanism that swings and displaces the coating gun, the swinging mechanism including: a support arm fixed to the main body side; a slide arm that is supported by the main body and reciprocates under the driving action of a drive source; and a coating gun support member that is swingably supported between the support arm and the slide arm; A coating apparatus characterized in that the support arm side shaft support portion of the coating gun support member is provided closer to the object to be coated than the nozzle tip of the coating gun.