JP2004033887A - Method and apparatus for spindle coating using coating robot - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To make continuous coating possible on spindles transferred on a conveyer in order to improve the productivity in the process of spindle coating by mounting a plurality of objects to be coated on rotation spindles and coating the objects while revolving. <P>SOLUTION: A rotation folder mounting a plurality of the objects to be coated is disposed on spindles connected to the continuously traveling conveyer. The rotation folder includes two areas with rotation in one direction and in the opposite direction. A spray gun opposing to the object in each of the rotation area is mounted on a coating robot, and coating is performed by the spray guns synchronously operated in the both rotation areas. The coating process on the object is completed while the object is passed through the both rotation areas. The distance between the spray guns disposed in two respective areas and mounted on the coating robot is made variable and can be relatively opposed in the rotation direction and in the opposite rotation direction. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of placing an object to be coated on a rotating spindle and painting by a painting robot, wherein a plurality of spray guns are applied to a spindle continuously attached to a conveyor. The present invention also relates to a method for simultaneously coating the coating portions of a plurality of objects to be coated simultaneously, and completing the coating of each object to be coated while passing through a coating area, thereby performing continuous coating.
[0002]
2. Description of the Related Art In the case of coating a large amount of objects to be coated, the objects to be coated which are sequentially fed by a conveyor are applied by passing through a spraying area of a spray gun which is continuously spraying. Used as the easiest method. However, in this case, the spraying is performed not only on the painted surface but also unnecessarily on the painted portion, so that the paint is wasteful, which is not preferable in terms of economy, resources and environment.
[0003] Particularly, in recent years, paintings that require high-grade appearance, such as mobile phones, audio equipment, and optical equipment, require high quality coatings as well as expensive coatings. Further, since these products are required to be manufactured at a low cost by mass production, it is necessary to realize highly efficient coating while maintaining high productivity.
[0004] In response to such demands, there is used an automatic spindle coating, in which a rotating folder on which a plurality of workpieces can be placed is provided on a rotating spindle as shown in FIG. Have been. According to this method, spray guns are arranged at several places according to the coating location on the workpiece to be coated while revolving one after another, and each spray gun paints the determined area, thereby applying the coating area. When it passes, the painting is completed, and the productivity can be improved by feeding the conveyor and disposing the spray gun.
However, even in this case, it is difficult to control the spraying individually, and unnecessary spraying is performed, so that the spraying paint is wasted as described above, so that a problem remains.
[0005] In order to eliminate such waste of the paint and to improve the finish quality of the paint, it is necessary to control the spray time more appropriately and to control the spray position and the spray direction and the spray distance. For this purpose, a painting robot or the like which operates while controlling the movement and spraying of the spray gun has been used, and a method in which the above-described spindle painting is combined with the painting robot has been employed.
However, even in this case, the painting robot installs a rotary spindle in a turntable type and performs the painting until the painting of the work placed on the rotating folder at the painting position is completed. Since the placed workpiece is sent to the painting position and enters the painting, productivity is reduced due to the difficulty of painting due to the moving time of the turntable and the difficulty of painting multiple rotating folders at the same time. was there.
[0007]
[Problems to be solved by the invention]
The present invention solves each of these problems, and aims to obtain a highly efficient coating method with high productivity, good finish of the coating, no waste of the coating, and a normal automatic spindle. The problem is to apply a coating method that combines high productivity of coating, high coating efficiency, and dedicated spindle coating by a coating robot that can obtain uniform coating film.
That is, the spraying position of the spray gun is set to the rotating folder for the object to be continuously transferred while being mounted on the rotating folder of the spindle, and a plurality of the objects to be coated are rotated by the operation without waste. If you paint by the method, productivity will increase. In order to keep the quality of the coated surface rotating at high speed high and to keep it constant, in the vertical application of the surface to be coated, the spray gun should be placed on the left side to the right of the center of the clockwise rotating spindle, and the right side Requires that the spray gun be located to the left of the center of the counterclockwise rotating spindle, and that the relative position between the spray gun and the rotating body be maintained.
[0009]
According to the present invention, in order to solve these problems, a rotating folder for placing a plurality of objects to be coated is provided on a spindle attached to a conveyor which is continuously fed and sequentially transferred. The coating robot is used to paint the coming objects to be painted.The rotating folder is rotated forward and backward in the first and second half of the painting area, and is mounted on the painting robot so as to face the rotating folders in both painting areas. Spray guns apply the same paint to the surfaces to be painted simultaneously on the left and right sides of the object to be painted, and spray them so that the painting process for each object is completed while passing through both rotating areas. To do. Thereby, a plurality of spindles can be coated simultaneously and continuously, and the productivity can be increased.
The spray guns for performing the synchronous operation are mounted on the arms of the painting robot and provided on both sides of the gun stay which moves in parallel with the conveyor, and are relatively movable with respect to the center of the gun stay. By spraying while setting or moving the spray gun to a position that is symmetrical with respect to the center of the spindle, the spraying position according to the direction of rotation can be adjusted to the object to be revolved, and paint can be effectively applied. Can be painted.
Further, productivity can be improved by providing a plurality of sets of spray guns on both sides of the gun stay and simultaneously spraying a plurality of rotating folders in both rotating areas.
According to a possible coating time while passing through one coating area, the same surface is continuously coated on a plurality of rotating folders in both coating areas, and then the next surface is coated in the same manner. A plurality of sets are grouped together and sprayed sequentially, so that the time required to pass through the coating area can be used as the coating time to the maximum and a process without wasted time can be set.
[0013]
FIG. 1 shows an example of an apparatus for carrying out a coating method according to the present invention. 1 is a coating robot that can spray while freely moving a spray gun attached to the tip of the arm 2 according to an operation signal from a control device separately provided. In this embodiment, a gun stay 3 is provided at a tip of the arm 2 substantially at right angles to the arm, and spray guns 4A and 4B are attached to both sides of the gun stay 3. These spray guns can be freely moved up and down, left and right, and up and down angles by the operation function of the coating robot 1 while being installed on the gun stay 3.
The gun stay 3 extends and contracts symmetrically at both ends with respect to a central portion attached to the coating robot 1, and the interval between the spray guns attached to both sides is variable. The extension mechanism may be selected within the range of the conventional elemental technology, for example, using a screw having a left-right reverse pitch or using a link mechanism. The operation is sent to a servomotor or the like similarly to the control signal of the painting robot, and is controlled at a necessary interval. In the case of the present embodiment, two spray guns are installed on both sides of the gun stay 3 as shown in the figure, and four spray guns are simultaneously operated on both sides to increase the coating efficiency.
The object to be coated is placed on a rotating folder 6 attached to a conveyor 5 disposed in front of the coating robot 1 and is carried to a coating position. Spindles 7 are provided on the conveyor 5 at predetermined intervals, and each of the spindles 7 is automatically rotated by rotation driving devices 15A and 15B provided in the coating area. As a means for rotating, a method or the like in which a rotational force is transmitted when a friction roller portion of a spindle comes into contact with a belt or the like rotated by a driving device is used. The directions of rotation of the rotary driving devices 15A and 15B are reversed as indicated by arrows, and the rotation of the spindle is configured to be reversely rotated in each region with the intermediate portion as a boundary.
As shown in FIG. 3, each of the spindles is provided with a rotating folder 6 around which four object folders 8 are provided. W revolves around the spindle 7. The number and shape of the object folder 8 may be changed depending on the size of the object to be coated and various coating conditions, and it is desirable that the rotating folder 6 can be easily replaced.
As described above, since the object to be coated is revolving, the spraying from the spray gun is performed while controlling the eccentric distance S from the center of rotation in accordance with the direction of rotation, and the efficiency of coating and the finish state Is improved. In addition, since the opposite surface is not sufficiently coated only from the same direction, it is necessary to perform coating by reverse rotation. In this case, the eccentric distance S is deviated from the center.
In the present invention, since the coating by both rotations is performed simultaneously and simultaneously performed by the spray guns provided on both sides of the gun folder provided in the coating robot, the positions of the spray guns placed in both the rotation areas are reversed. It is necessary to be eccentric, and as a means to cope with this, a gun stay in which the interval between the mounting positions of the spray gun is variable is adopted.
FIG. 2 shows the movement of the conveyor 5 and the spindle 7 and the positional relationship between the spray guns 4A and 4B installed on the gun stay 3 of the coating robot 1. For example, the spindle 7 attached to the conveyor 5 moving to the right side from the left side of the coating area is rotated left and right before and after the intermediate part, as described above, and each of the spray guns 4A and 4B is The installation and movement are performed so as to face the object to be coated (the rotating folder) in the range of the rotating area.
Normally, when painting is performed irrespective of the direction of rotation of the folder, a spray gun is arranged at the center of rotation. When the spray gun is pointed, the film thickness on the left and right side surfaces and the front surface of the object to be coated becomes uneven. Further, by arranging the spray gun at the position where the painted surface is approaching, the coating efficiency can be increased and the finish can be improved. Conversely, spraying in the direction away from the spray of the spray gun not only reduces the coating efficiency, but also increases the coating of coarse particles with a high spraying speed, resulting in a bad effect on the finish.
Therefore, as shown in FIG. 2, the left rotating folder 6A is set rightward from the center of rotation, and the right rotating folder 6B is set leftward from the center of rotation. In the case where the eccentric distance from the center of rotation differs depending on the object to be coated or the coating portion, the distance is adjusted by extending or shortening the interval X between the spray guns on both sides to be installed. Furthermore, if the effect of painting can be obtained by spray painting while moving the spray gun from the center of rotation to the outside, for example, the interval between the spray guns on both sides can be changed during operation. Will be needed. These movements can be taught as operation control signals of the painting robot to control the operation as described above.
A coating room 10 is provided around the conveyor 5, which is a coating area, for preventing dust from entering the room and exhausting paint mist.
The coating actually performed by these configurations will be described in detail below. As shown in FIG. 3, four objects to be coated are placed on the rotating folder 6 provided on the spindle 7 of the conveyor 5 and are sequentially sent to the coating area. The lower surface, the middle surface, and the upper surface are painted by the painting robot 1 programmed in advance while revolving rightward until reaching the center of the painting area. At this time, the objects placed on the two rotating folders (first two folders) are simultaneously sprayed by the two spray guns 4A on the left, and then another two rotating folders (second two folders). The painting robot moves to move the lower surface of the placed object to the next two rotating folders (third two folders) to sequentially paint the lower surface of the placed object.
For the next middle surface, the third two folders, the second two folders, and the first two folders are painted again in that order, and finally the top surface is the first two folders, the second two folders. Then, paint in order of the third two folders and finish painting in the left rotating area. Then, the conveyor speed and the spray time are adjusted so that the first to third folders are sent to the reverse rotation area on the right side.
The object to be fed sent to the right side of the next rotating area is rotated in the reverse direction and revolves around the spray gun 4B located on the left side of the rotary shaft with the coating surface on the opposite side from the previous one facing the spray gun 4B. .
That is, the painted surface on which the painting was not sufficiently performed in the left region is painted in the right region, and a uniform painted surface as a whole is formed. In this state, the same coating as that of the spray gun 4A is performed, and the coating is completed. Of course, while the spray gun 4B performs these coatings, the next set of objects to be coated is subjected to the same coating by the spray gun 4A, and the coating is sequentially performed.
In this example, six folders are set as one set so that each of the six folders is painted and completed. However, the conveyor speed and the number of paintings are set so that the movement of the painting robot between the rotating folders is minimized. The setting of the painting time is adjusted so that the position of the painting robot returns to the origin position when one set of painting is completed.
In the present invention, a necessary part is sprayed on the object to be coated by using the coating robot, and the spraying is interrupted when moving to the next object to be coated or the next coated surface. Efficient painting can be performed only by spraying.
[0029]
According to the spindle coating method using the coating robot as described above, the following effects can be obtained.
That is, according to the present invention, when a rotating spindle is connected to a continuous feed conveyor and the object to be revolved is painted, the rotating direction of the spindle is divided into forward and reverse rotating areas, and the two areas operate synchronously. The spray gun mounted on the coating robot is revolved by the spindle, and the spray position is adjusted to the direction of rotation. The coating is characterized in that it is possible to apply a large number of objects to be transferred at the same time, so that coating can be performed continuously without waste and productivity can be improved.
Also, the positions of the spray guns mounted on both areas are always properly set by expansion and contraction of the gun stays so that the object to be revolved can be symmetrically confronted by the spindle rotating forward and backward. Switching time required for spindle painting, changing the spraying position of the painting robot, and moving the table required for turntable type spindle painting can be saved, minimizing painting downtime. It can increase productivity by holding down. According to the embodiment of the present invention, a production amount that is two to three times per hour is obtained as compared with the case of the turntable type.
Further, since the spindle coating can be performed on the continuous conveyor using the coating robot, the amount of the coating material to be coated can be reduced to about 1/5 as compared with the conventional spindle coating using the fixed gun. And drastically reduced the amount of paint used. This means that automatic spindle coating is continuous spraying, whereas the method of the present invention is spraying only when necessary, and the appropriate spray distance, spraying position, and target angle are adjusted for the workpiece. This is because spraying can be performed while following, and the most efficient spraying position can be selected for the revolving work.
Although not specified, in order to enhance the effect of the present invention, a more stable coating is possible by incorporating a flow rate control device in the path of each spray gun. The coating effect can be further improved by using various auxiliary devices that incorporate control of a coating robot such as a combination of installation and control of a color changing device and automatic cleaning of a spray gun air cap.
As described above, according to the present invention, it is possible to perform coating with high productivity, excellent coating efficiency, and excellent finish. can get. In addition, the emission of paint can be reduced, waste can be reduced, resources can be effectively used, and the impact on the environment can be greatly improved.
[Brief description of the drawings]
FIG. 1 is an overall schematic view showing an example of a robot coating apparatus used for carrying out the present invention. FIG. 2 is an arrangement view of a spray gun facing a spindle. FIG. 3 is an arrangement view of an object to be coated placed on a spindle and revolving and a spray gun. [Explanation of symbols]
1, painting robot 2, painting robot arm 3, gun stay 4A, 4B, spray gun 5, conveyor 6, rotating folder 7, spindle 8, workpiece folder W, workpiece

Claims (4)

In a method of coating a workpiece to be transported sequentially and in a rotating state by providing a rotating folder for mounting a plurality of workpieces on a spindle continuously attached to a conveyor that is continuously fed, by a coating robot. The rotating folder is rotated forward and backward in the first half and the second half of the coating area, respectively, and faces the rotating folders in both rotating areas, respectively, and paints each coated surface with a spray gun mounted on a coating robot and operated synchronously. A coating method in which spraying is performed so that the coating process for each workpiece is completed while passing through the rotating area. Spray guns that perform synchronous operation are provided on both sides of a gun stay that is mounted on the arm of the painting robot and moves parallel to the conveyor, and can be moved relatively to the center of the gun stay. The coating method according to claim 1, wherein the spraying is performed while expanding and contracting the relative distance between the two spray guns so as to set the spray guns at symmetrical positions. 3. The coating method according to claim 1, wherein a plurality of sets of spray guns are provided on both sides of the gun stay, and spraying is performed simultaneously on a plurality of rotating folders in both rotating areas. In the coating method according to claim 1 or 2, after the same surface is continuously coated on a plurality of rotating folders in both rotating areas according to a possible coating time while passing through one rotating area, A painting method in which the surfaces are painted in the same way, a plurality of them are grouped together and sprayed sequentially

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