JPS6220863B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a coating method in which a pair of painting guns that discharge paint toward the object are used to paint an object that is advancing toward each of the painting guns. be.

Conventionally, as a painting device for painting objects with uneven surfaces, such as the upper surface of a vehicle, a gate-type reciprocator was installed at a high point in the painting booth and was able to move left and right. A pair of painting guns are provided, and the pair of painting guns are set downward (vertically) so as to be perpendicular to the object to be coated that is advancing toward them, and the object to be coated is placed on a conveyor and is advancing. In order to speed up the painting process, a type of paint gun that simultaneously discharges paint from a pair of paint guns is known.

However, such prior art coating apparatuses have a number of drawbacks. That is, when first starting painting, paint is discharged from a pair of paint guns at the same time, so the amount of paint discharged may be too large depending on the area to be painted which has an uneven shape, and the paint may be discharged in an excessive amount due to the unevenness of the cowl area, etc. The drawback was that paint accumulates in the shaped part, causing a ``sagging phenomenon'' in which the paint flows. Secondly, parts of a vehicle where the windshield, rear glass, doors, etc. are to be installed have a small surface area to be painted, so when painting with an electrostatic sprayer, the paint is concentrated on a small surface area. However, as mentioned above, there was a drawback that the "sagging phenomenon" occurred. In order to eliminate this phenomenon, paint was not discharged in areas corresponding to the glass frame, center pillar between doors, etc., and a separate correction coat was applied, but this increased the number of painting steps and resulted in poor workability. It was hot. Third
In addition, since the painting gun, which is directed downward perpendicularly to the object to be coated, is only fixedly attached to the reciprocator, there are sloped parts of the uneven shape that are not perpendicular to the painting gun, such as the convex shape on the front of the body. There is little paint adhering to the parts, cowls, etc., which not only requires a separate correction coat, but also causes the paint to scatter unnecessarily, reducing painting efficiency.

The present invention was made in view of the drawbacks of the conventional coating methods described above, and aims to provide a coating method that prevents wasteful consumption of paint, eliminates sagging phenomenon, and increases coating efficiency. .

In order to achieve this objective, the present invention utilizes a pair of paint guns that discharge paint toward the object to be coated.
In a coating method in which painting is performed on an object to be coated that is moving toward each of the painting guns, the pair of painting guns located parallel to the axis in the direction of movement of the object to be coated can be oriented in any direction with respect to the object to be coated. The head oscillation process causes the head to oscillate, and among the pair of painting guns, the one closer to the object to be coated starts discharging paint before the one farther away. Moreover, it is characterized by having a paint discharging stroke in which the discharging of paint is stopped first.

The present invention will be described in detail below with reference to FIGS. 1 to 4.

FIG. 1 shows an overall view of the coating apparatus used in the present invention. In the figure, 1 is a gate-shaped reciprocator installed in the coating booth, and the reciprocator 1 has columns 2, 2, 2 vertical movement (arrows X-X
It consists of a vertically movable frame 3 that moves vertically (direction), and a cable 4 such as a chain or wire that is provided on the vertically movable frame 3 so that it can move laterally (in the direction of arrow Y-Y). A coating machine 5 is provided on the cable 4, and the coating machine 5 has a configuration shown in FIGS. 2 and 3, which will be described later. Reference numeral 6 indicates a vehicle as an object to be coated, and the vehicle 6 is placed on conveyors 7, 7, and while the conveyor 7 is moving at a predetermined speed, a coating machine 5 is installed in the coating booth.
is configured to perform painting work by moving in the directions of arrows X-X and Y-Y and discharging paint.

Next, the specific configuration of the coating machine 5 will be described with reference to FIGS. 2 and 3. That is, the paint sprayer 5 has a bracket 11 fixed to the cable 4, a mounting plate 12 is fixed to the bracket 11 in a vertical direction, and a support arm 13 is provided at the bottom of the mounting plate 12. There is. Then, the mounting plate 12 and the support arm 13
A swinging mechanism 14 is provided between the two.

Here, the swinging mechanism 14 includes a rotating shaft 15 that is rotatably provided on the support arm 13, and an arm 16 for attaching a painting gun that is fixed to the rotating shaft 15, which are coaxial. It is composed of cylinder mechanisms 17, 18, etc. And each cylinder mechanism 17, 1
8, as shown in FIG. 4, pistons 17B and 18B are slidably provided in cylinders 17A and 18A, respectively.
Then, extend the cylinders 17A and 18A and attach the rod 1.
7C and 18C are provided, and the cylinders 17A,
18A has suction and exhaust ports 17D, 17E, and 18, respectively.
D, 18E are formed, and each cylinder 17A,
18A is coaxially fixed via an intermediate member 19. Therefore, the rod 17C is rotatably attached to the mounting plate 12, and the rod 18C is rotatably attached to the pin 20 implanted in the arm 16.

In addition, a rotation shaft 15 is attached to the arm 16 for attaching the painting gun.
A pair of painting guns 21 and 22 are provided at symmetrical positions. The painting guns 21 and 22 are arranged parallel to the axis in the traveling direction Z of the vehicle 6, which is the object to be painted, with the painting gun 21 being the gun closest to the vehicle 6, and the other painting gun 22 The cancer is on the far side.

Moreover, the coating guns 21 and 22 are in the downward position perpendicular to the conveyor 7 (see FIG. 1) in the state shown in FIG. In this state, compressed air is supplied to the supply/discharge ports 17D and 18D as shown in FIG. 4, and only the cylinder mechanism 18 is extended. Also, paint gun 2
1 and 22, the positions indicated by imaginary lines 21' and 22' in FIG. 2 are forward positions facing the traveling direction Z of the vehicle 6 (hereinafter, 21' and 22' are referred to as forward positions). In this state, compressed air is supplied to the supply/discharge ports 17D and 18E, and both the cylinder mechanisms 17 and 18 are contracted. Furthermore, the positions of the painting guns 21 and 22 indicated by imaginary lines 21'' and 22'' in FIG. ).
The painting guns 21 and 22 used in the present invention may be any type of painting gun, such as an air painting gun or an electrostatic painting gun.

Next, according to FIG. 4, the cylinder mechanisms 17, 18,
A control circuit for controlling the painting guns 21, 22, etc. will be explained. 31 is a pressure air source;
are electromagnetically actuated 4-port 2-position switching valves 32, 33 (hereinafter referred to as switching valves 32, 33) as shown in the figure.
The switching valves 32, 33 supply compressed air to the supply/discharge ports 17D, 18D when they are in the switching positions 32A, 33A, and supply compressed air to the supply/discharge ports 17D, 18D when they are in the switching positions 32B, 33B. It is configured to supply compressed air to 17E and 18E.

Further, 34 is a paint tank, and the paint tank 34
is connected to the painting guns 21 and 22 via a paint pipe 35 that branches into paint pipes 35A and 35B from the middle, and a pump 36 for pumping the paint is provided in the middle of the paint pipe 35.
A, 35B are provided with electromagnetically actuated two-port, two-position switching valves 37, 38 (hereinafter referred to as switching valves 37, 38) that constitute a paint control mechanism.

Further, 39 indicates each of the switching valves 32, 33, 3.
7 and 38, the control section 3
Reference numeral 9 receives a conveyor speed signal from a conveyor speed detection unit 40 provided on the conveyor 7, a vehicle position signal from a vehicle position detection unit 41 that detects the position of the vehicle 6 placed on the conveyor 7 and advancing, and A valve switching signal is output to each switching valve 32, 33, 37, 38. Here, the control unit 39 has a built-in switch group, a timer, etc. that rotates in proportion to the amount of movement of the conveyor 7 based on a signal from the conveyor speed detection unit 40, and the switch group includes a switch group that rotates in proportion to the amount of movement of the conveyor 7. The switching timing of the valves 32, 33, 37, and 38 is set, the rotation of the switch group is started by a signal from the vehicle position detection section 41, and a switching valve control signal is output from the switch group. As for the electrical system, a computer system is employed which receives signals from the conveyor speed detection section 40 and vehicle position detection section 41 and operates according to a predetermined program procedure.

The apparatus used in the coating method of the present invention is constructed as described above, and the coating process will be described with reference to the explanatory diagram shown in FIG. In FIG. 5, for ease of explanation, the vehicle 6 to be coated includes a body front convex portion 6A, a bonnet portion 6B, a cowl portion 6C, a windshield portion 6D, a roof tip convex portion 6E, a roof portion 6F, It will be described as being composed of a roof rear end convex portion 6G, a rear glass portion 6H, a trunk lid base concave portion 6J, a trunk portion 6K, a body rear convex portion 6L, etc.

First, the vehicle 6 is placed on the conveyor 7 and moves at a predetermined speed, and the vehicle detection unit 41 detects the position TO
When the vehicle detection signal reaches the controller 39,
starts operating.

When the vehicle 6 reaches the painting start position TA, the switching valves 32 and 33 are actuated by the output from the control section 39, and the swinging mechanism 14 is actuated. That is, supply/discharge port 1
Compressed air is supplied to 7D and 18E to reduce the cylinder mechanisms 17 and 18, and the painting guns 21 and 22 are moved from the downward position to the forward position 21', 21' and 22' around the rotation axis 15.
22', body front convex shape part 6A
The direction is perpendicular to . At the same time, only the switching valve 37 is switched at point A to start discharging paint from the paint gun 21 on the side closer to the vehicle 6, and
The body front convex portion 6A is painted. In this case, in order to prevent the paint from being wasted and to prevent the "sagging phenomenon" from occurring in this part, the paint is not discharged from the paint gun 22 and the paint is discharged from the bonnet part 6B.
At point A' approaching , the switching valve 38 is switched and paint discharge is started.

When the vehicle 6 moves forward and reaches the bonnet tip position TB, since the bonnet part 6B is flat, the switching valve 3 is activated by a signal from the control part 39 so that the painting guns 21, 22 and the bonnet part 6B are perpendicular to each other.
2 and 33 to the state shown in Fig. 4, and paint gun 2.
1 and 22 are in the downward position. In this state, the pair of painting guns 21 and 22 are operated simultaneously to sufficiently paint the bonnet portion 6B, which has a large coating area.

Next, when the vehicle 6 advances close to the cowl portion 6C and reaches the bonnet rear end position TC, the paint gun 21,
22 to the forward facing position 21', 22' again,
The concave portion of the cowl portion 6C is orthogonal to the windshield portion 6D. Thereafter, the paint discharge from the paint gun 21 is stopped at point B to prevent excessive paint from being applied to the cowl part 6C and the windshield part 6D, and the windshield part 6D is painted only by the paint gun 22, and the paint is painted at point B'. Discharge is stopped at . In addition, the discharge of the paint is stopped between the areas 'with a narrow coating area' to prevent the windshield portion 6D from being overfilled with paint.

Next, when approaching the roof tip convex portion 6E, paint discharge from the paint gun 21 is resumed at point C.
This portion is painted while being perpendicular to the roof tip convex portion 6E. Vehicle 6 advances and paint gun 2
2 is at the position corresponding to the roof part 6F, the point
At C', paint application from the paint gun 22 is resumed, and the pair of paint guns 2
Paint according to steps 1 and 22. And paint gun 2
When the coating guns 21 and 22 reach the roof tip position TD where they are completely located on the flat roof portion 6F, the coating guns 21 and 22 are swung downward to continue coating.

When the vehicle 6 advances and reaches the roof rear end position TE, the paint discharge from the paint gun 21 is stopped at point D, and the paint guns 21 and 22 are moved to the rear facing position 2.
1", 22" to swing the roof rear end convex portion 6G
The painting of this part is continued only by the paint gun 22 on the side far from the vehicle, and the paint discharge is stopped at point D'.

The paint guns 21 and 22 are maintained perpendicular to the rear glass portion 6H while the vehicle 6 is advanced;
Paint discharging is stopped between the areas where the painting area is narrow, and when approaching the concave portion 6J of the trunk lid base, paint discharge from the paint gun 21 is resumed at point E, and the paint is discharged from the rear glass portion 6H and the trunk lid base. The concave portion 6J is painted. When the paint gun 22 reaches the position corresponding to the trunk portion 6K, the paint discharge by the paint gun 22 is resumed at point E'.
The trunk part 6K, which has a large painting area, is painted by a pair of painting guns 21 and 22. At this time, since the trunk lid base concave portion 6J is painted only by the coating gun 21, paint does not accumulate in the concave portion of this portion.

Furthermore, the trunk tip position corresponding to the trunk portion 6K where both the painting guns 21 and 22 are flat is shown.
When reaching the TF, these are swung downward to be perpendicular to the trunk portion 6K. When the vehicle 6 advances and the paint gun 21 reaches a position corresponding to the body rear convex portion 6L, the paint discharge from the paint gun 21 is stopped at point F. When reaching the rear end position TG of the body, move the painting guns 21 and 22 to the backward position 21'',
22" and attach these to the body rear convex portion 6.
Orthogonal to L. In this position, the painting gun 22 on the side far from the vehicle 6 (in the rear end part, the paint gun 22 is actually
The paint is continued to be discharged only from the point (which is close to 1), and the body rear convex portion 6L and the rear surface portion are painted, and the paint discharge is ended at point F'.

The painting method of the present invention operates according to such steps, but a pair of painting guns 21 and 22 located parallel to the axis in the traveling direction Z of the vehicle 6, which is the object to be painted, is applied to the uneven shape of the vehicle. A swinging process of swinging these so that they are always perpendicular to each other, and a pair of painting guns 21,
22, the paint gun 21 on the side closer to the vehicle 6 starts discharging paint before the paint gun 22 on the far side, and also stops the paint discharge first. Even if the process is repeated multiple times (three times in the embodiment shown in FIG. 5), by performing the process under the same conditions, it is possible to prevent the "dripping phenomenon" caused by excessive paint, and also to prevent the windshield portion 6 from sagging.
D. Prevents excess paint from areas where painting is not required, such as the rear glass portion 6H, and prevents paint from accumulating in the cowl portion 6C, trunk lid base concave portion 6J, etc., and also prevents wasted paint consumption. prevent.

In the embodiments of the present invention, the case where the painting work is performed on the vehicle 6 as the object to be painted has been described, but the invention is not limited to this, and for example, office equipment such as desks and book cases, air compressors, boilers, etc. Of course, it can be applied to industrial machinery and the like. In addition, although the switching valves 32, 33, 37, 38, etc. as a paint control mechanism have been described as electromagnetically actuated switching valves, air-operated switching valves may also be used in consideration of explosion protection against cleaning liquid such as thinner. It is something.

Since the coating method of the present invention has been described in detail above, it achieves the following effects.

Since the pair of paint guns located parallel to the axis of the object to be painted are oscillated in a direction perpendicular to the painted surface of the object to be painted, it is possible to completely adhere the paint to the surface to be painted, and the paint can be painted easily. Efficiency can be increased and wasteful consumption of paint can be prevented.

Of a pair of painting guns, the one that is closer to the object to be coated starts discharging paint before the one that is farther away, and also stops discharging paint first. Because of this configuration, the coating gun that reaches the object to be coated first can start and finish coating first, and wasteful discharge of paint can be prevented.

As a result of the above-mentioned configuration, it is possible to control the amount of paint discharged according to the uneven coating area and ensure reliable coating, which prevents the occurrence of "sagging phenomenon" and also prevents uneven coating. It can reliably prevent paint from accumulating in the area.

Painting areas with large areas can be painted simultaneously using a pair of paint guns, which increases work efficiency by speeding up the progress of the object to be painted, and enables uniform painting. This eliminates the need for correction coating and reduces the number of painting steps.

[Brief explanation of the drawing]

Fig. 1 is an overall view of the coating device used in the present invention, Fig. 2 is an external view showing the coating gun and the swing mechanism, and Fig. 3
The figure is a right side view of FIG. 2, FIG. 4 is a circuit diagram for driving the coating gun and cylinder mechanism, and FIG. 5 is an explanatory diagram showing the coating process. DESCRIPTION OF SYMBOLS 1...Reciprocator, 2...Painting machine, 6...Object to be coated, 7...Conveyor, 14...Obcillating mechanism, 15...Rotating shaft, 16...Painting gun mounting arm, 17, 18...Cylinder mechanism, 21, 22 ...painting gun, 32, 33,
37, 38...Switching valve, 39...Control unit, 40...Conveyor speed detection unit, 41...Vehicle position detection unit, Z...Progressing direction of object to be coated, 21', 22'...Forward position, 2
1″, 22″…Rearward position.

Claims (1)

[Scope of Claims] 1. A coating method in which a pair of painting guns that discharge paint toward the object are used to paint an object that is advancing toward each of the guns, the object being coated is a swinging process in which the pair of painting guns, which are located parallel to the axis in the advancing direction, are swung in any direction relative to the object to be coated; This painting method comprises a paint discharging process in which a paint gun on a closer side starts discharging paint before a paint gun on a farther side and stops discharging the paint first. 2. The coating method according to claim 1, wherein the oscillating stroke includes oscillating the coating gun in a direction perpendicular to the shape of the object to be coated. 3. The paint discharging process is repeated multiple times, and in all repeated paint discharging processes, the paint gun closer to the object to be coated starts discharging paint before the paint gun farther away. The coating method according to claim 1, further comprising first stopping the discharge of the paint.