JP2001029848A - Supply device of powder coating material to coating gun - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve coating quality by preventing the flowing-out of a powder coating material left in a transporting pipe line from a coating gun at the time of completing the coating, in a supply device of the powder coating material to a coating gun, which is constituted so that the powder coating material discharged from a powder coating material vessel by a fixed quantity supply means is supplied to the coating gun through the transporting pipe line by compressed air passing an injector. SOLUTION: In this device, a 1st control valve 16 is provided in the transporting pipe line 14 between the injector 15 and the coating gun 4, and a 2nd control valve 19 is installed to be interposed in a powder recovering pipe line 18 branched from the transporting pipe line 14 between the 1st control valve 16 and the injector 15 and connected to a powder recovering tank 17. At the time of coating a work W to be coated, the fixed quantity supply means 7 is brought into a working state and simultaneously the 1st control valve 16 is opened and the 2nd control valve 19 is closed and, at the time of completing the coating of the work W to ba coated, the fixed quantity supply means 7 is brought into a stopping state and simultaneously the 1st control valve 16 is closed and the 2nd control valve 19 is opened.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for supplying a powder coating material to a coating gun, and more particularly to a powder coating material which is fed from a powder coating container by a constant supply means by a pressurized air flowing through an injector. The present invention relates to an apparatus for supplying a powder coating material to a coating gun through a path to the coating gun.

[0002]

2. Description of the Related Art Conventionally, such an apparatus is disclosed in, for example,
It is already known from -75790 and the like.

[0003]

However, in the above-mentioned conventional apparatus, a valve for controlling the flow of the powder coating material between the coating gun and the injector in the conveying pipe is not provided.
When the supply of the powder paint by the quantitative supply means is stopped in order to end the coating of the workpiece to be coated by the coating gun, the powder paint remains with the pressurized air in the transfer pipe between the coating gun and the injector, The powder paint flows out from the paint gun even after painting is completed. In particular, when the surface to be painted facing upward, such as the roof, hood and trunk lid of an automobile body, is painted by a painting gun disposed above the surface to be painted, the powder remaining in the conveying conduit is not sufficient. The body paint adheres to the surface to be coated, which may lower the coating quality.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and it is possible to prevent the powder paint remaining in a conveying pipe at the end of coating from flowing out of a coating gun and improve coating quality. It is an object of the present invention to provide an apparatus for supplying a powder coating material to a coating gun.

[0005]

In order to achieve the above object, according to the first aspect of the present invention, a powder paint container for storing powder paint and a powder paint can be sent out from the powder paint container. A fixed amount supply means provided at the bottom of the powder paint container, a transfer pipe having one end connected to a pressurized air source and the other end connected to a coating gun, and a transfer pipe provided at an intermediate portion of the transfer pipe. And a injector connected to the discharge port of the fixed-quantity supply means for supplying the powder coating material to the coating gun, wherein the first control valve is provided in the transport conduit between the injector and the coating gun; A powder recovery pipe branched from the transport pipe between the control valve and the injector and connected to the powder recovery tank; a second control valve interposed in the powder recovery pipe; Opening and closing of the second control valve Control means for controlling the operation of the quantitative supply means, wherein the control means opens the first control valve and closes the second control valve while activating the quantitative supply means at the time of painting the workpiece to be coated. When the coating of the workpiece is completed, the first control valve is closed and the second control valve is opened while the fixed amount supply unit is stopped.

According to the configuration of the first aspect of the present invention, when the coating of the workpiece to be coated is completed, the operation of the quantitative supply means is stopped, the first control valve is closed, and the second control valve is opened. Since the valve is opened, the powder paint remaining in the transfer pipe between the injector and the first control valve flows to the powder recovery tank through the second control valve. Therefore the first
By installing a control valve as close as possible to the coating gun in the transfer line, it is possible to prevent the powder paint remaining in the transfer line from flowing out of the coating gun at the end of coating as much as possible and to improve the coating quality. It is also possible to collect excess powder paint in the powder recovery tank and reuse it.

[0007] The invention according to claim 2 provides the above-described claim 1.
In addition to the configuration of the invention described in the above, the method further includes a work transfer unit that transfers the work to be coated so as to pass through a position corresponding to the coating gun, wherein the control unit controls the transfer after the work transfer unit is once stopped. Prior to the restart of the workpiece to be transported to the position corresponding to the coating gun by the workpiece transport means at the time of resumption, the first and second control valves are closed, and the transport pipe between the injector and the first control valve is closed. A valve closing state for controlling the operation of the work transfer means and the fixed quantity supply means so as to start the transfer of the work to be coated by the work transfer means after the fixed quantity supply means is operated so as to fill the road with the powder paint; After activating the fixed-quantity supply means so as to fill the transfer pipe between the first and second control valves and the injector, the work transfer means, To start conveyance of the paint work with, the first control valve, the second control valve, and controls the operation of the workpiece conveying means and the dispensing means.

According to the construction of the second aspect of the present invention, the inside of the conveying pipe is emptied with the completion of coating, but the next workpiece to be coated is moved to a position corresponding to the coating gun. Before being conveyed, the transfer pipe between the injector and the first control valve is filled with the powder paint, and as the work to be coated is conveyed to the position corresponding to the coating gun, the coating is performed. The coating by the gun can be started immediately, and the powder coating can be efficiently supplied to the coating gun in accordance with the transport of the workpiece to be coated.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the present invention will be described based on one embodiment of the present invention shown in the attached drawings.

FIGS. 1 and 2 show an embodiment of the present invention. FIG. 1 is a view showing a relative arrangement of a workpiece to be coated and a coating gun in a coating state, and FIG. FIG. 3 is a diagram showing a circuit configuration of FIG.

First, in FIG. 1, a work W to be coated, such as an automobile body, is transferred by a work transfer means 1 in a coating booth, and a range limited in the transfer direction of the work W to be coated by the work transfer means 1. The movable column 2 which can be moved by is arranged on the side of the work transfer means 1. An arm 3 disposed above the workpiece W on the work transporting means 1 is provided above the movable support 2.
, A plurality of coating guns 4, 4,...

In FIG. 2, a powder paint 5 is stored in a powder paint container 6, and a screw feeder 7 is provided at the bottom of the powder paint container 6 as a quantitative supply means. The screw feeder 7 has a supply pipe 10 having an intake port 8 at one upper end and a discharge port 9 at the lower end on the other end, and a screw shaft 11 accommodated in the supply pipe 10. And a motor 12 connected to one end of the screw shaft 11 and attached to one end of the supply pipe 10. By rotating the motor 12 at a constant speed, the powder paint is powdered. It can be sent out from the paint container 6 in a fixed amount per unit time.

The pressurized air source 13 is connected to one end of a transfer pipe 14 made of a rubber hose or the like, and the other end of the transfer pipe 14 is connected to the coating gun 4. An injector 15 is provided at an intermediate portion of the transport pipe 14, and the injector 15 is connected to the discharge port 9 of the screw feeder 7. When the screw feeder 7 is operated in a state where the pressurized air is supplied from the pressurized air source 13, the pressurized air flows through the injector 15 so that the powder paint flows from the discharge port 9 into the transport pipe 14. The powder paint is sucked and transported to the coating gun 4 in the transport pipe 14 together with the pressurized air.

A first control valve 16, which is a normally-closed solenoid valve, is provided at a position as close as possible to the coating gun 4 in the transport line 14 between the injector 15 and the coating gun 4.
Further, a powder recovery pipe 18 made of a rubber hose or the like is branched from a position as close as possible to the first control valve 16 in the transfer pipe 14 between the first control valve 16 and the injector 15. Pipe 18 is a powder recovery tank 17
Connected to. In addition, a second control valve 19, which is a normally-open solenoid valve, is provided at a position as close as possible to a branch point of the powder recovery line 18 from the transfer line 14.

Further, a third control valve 20, which is a normally-closed solenoid valve, is provided between the injector 15 and the pressurized air supply source 13 in the conveying line 14.

Transport / stop of the workpiece transport means 1;
Turn on / off the motor 12 in the screw feeder 7
Off operation, and first to third control valves 16, 19, 20
Is controlled by the control means 21.

The control means 21 opens the first and third control valves 16 and 20 and activates the second control valve while the motor 12 of the screw feeder 7 is in an operating state when the workpiece W is coated. 19, the first and third control valves 1 are stopped while the operation of the motor 12 of the screw feeder 7 is stopped when the coating of the workpiece W is completed.
The valves 6 and 20 are closed and the second control valve 19 is opened.

The control means 21 controls the work transfer means 1 when the transfer is resumed after the work transfer means 1 is once stopped.
Prior to the transfer of the workpiece W to the position corresponding to the coating guns 4, 4,... By the first and second control valves 16, 1,.
9 is closed, the motor 12 of the screw feeder 7 is operated so that the powdery paint 5 is filled in the conveying pipe 14 between the injector 15 and the first control valve 16, and the third control valve 20 is operated. After the valve is opened, the transfer of the work W to be coated by the work transfer means 1 is started.

Next, the operation of this embodiment will be described. When the painting of the workpiece W is completed, the operation of the screw feeder 7 is stopped, the first control valve 16 is closed, and the second control valve 19 is opened. The injector 15
The powder coating material 5 remaining in the transfer pipe 14 between the first control valve 16 and the first control valve 16 is transferred to the powder collection tank 17 via the second control valve 19.
Will be distributed to the side. Therefore, by providing the first control valve 16 in the transfer line 14 as close as possible to the coating gun 4, the powder paint 5 remaining in the transfer line 14 at the end of coating is prevented from flowing out of the coating gun 4 as much as possible. Even if the coating gun 4 is arranged above the work W to be coated, the powder paint 5 flowing out of the coating gun 4 is prevented from adhering to the work W to be coated as much as possible to improve the coating quality. Can be achieved. In addition, the excess powder coating 5 can be recovered in the powder recovery tank 17 and reused.

Although the inside of the conveying pipe 14 is emptied with the completion of the coating, the injector 15 and the first pipe 15 are moved before the next work W to be coated is conveyed to the position corresponding to the coating gun 4. The powder coating material 5 is filled in the transfer pipeline 14 between the one control valve 16. Accordingly, the coating by the coating gun 4 can be started immediately in response to the workpiece W being transported to the position corresponding to the coating gun 4, and the powder coating 5 can be transferred in accordance with the transport of the workpiece W. Thus, it can be efficiently supplied to the coating gun 4.

Although the embodiments of the present invention have been described in detail above, the present invention is not limited to the above embodiments, and various design changes can be made without departing from the present invention described in the appended claims. It is possible to do.

For example, in the above embodiment, the injector 1
A third control valve 20 is provided in the conveying line 14 between the first control valve 5 and the pressurized air supply source 13, and the operation of the third control valve 20 is controlled by the control means 21, but the third control valve 20 is omitted. In this case, the supply / stop of the powder coating material by the transport pipeline 14 can be switched only by the on / off control of the screw feeder 7.

The fixed amount supply means is a screw feeder 7.
However, the present invention is not limited to this.

[0024]

As described above, according to the first aspect of the present invention, it is possible to prevent the powder coating material remaining in the conveying pipe from flowing out of the coating gun at the end of coating as much as possible to improve the coating quality. In addition, the excess powder paint can be collected in the powder collection tank and reused.

According to the second aspect of the present invention, the powder coating material can be efficiently supplied to the coating gun in accordance with the transport of the work to be coated.

[Brief description of the drawings]

FIG. 1 is a view showing a relative arrangement of a work to be coated and a coating gun in a coating state.

FIG. 2 is a diagram showing a circuit configuration of a powder coating material supply device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Work conveyance means 4 ... Coating gun 5 ... Powder paint 6 ... Powder paint container 7 ... Screw feeder as fixed-quantity supply means 9 ... Discharge port 13 ... Addition Compressed air source 14 ··························· Injector 16 ··································································································· ..Control means W: Work to be coated

Claims (2)

[Claims] A powder paint container (6) for storing a powder paint (5), and a powder paint container (6) capable of sending the powder paint (5) out of the powder paint container (6). A fixed amount supply means (7) provided at the bottom of the container, and a pressurized air source (1) at one end.
3) The other end is connected to the coating gun (4), and the other end is connected to the coating gun (4). An apparatus for supplying a powder coating material to a coating gun, comprising an injector (15) connected to an outlet (9), provided in the transport conduit (14) between the injector (15) and the coating gun (4). A first control valve (16), and a powder recovery pipe branched from the transfer pipe (14) and connected to the powder recovery tank (17) between the first control valve (16) and the injector (15) Path (18), a second control valve (19) interposed in the powder recovery pipe line (18), opening and closing operations of the first and second control valves (16, 19), and a quantitative supply means (7). ) For controlling the operation of the control means (21). The first control valve (16) is opened and the second control valve (19) is closed while the fixed quantity supply means (7) is in the operating state when the work (W) is coated, and the work (W) is coated. The powder paint, wherein the first control valve (16) is closed and the second control valve (19) is opened while the fixed quantity supply means (7) is stopped at the end of the coating of (W). Supply device for paint gun. 2. A work transfer means (1) for transferring the work (W) to be coated so as to pass through a position corresponding to the coating gun (4), wherein the control means (21) controls the work transfer. When transporting is resumed after the means (1) is once stopped, prior to transporting the workpiece (W) to be coated to a position corresponding to the coating gun (4) by the workpiece transporting means (1),
The first and second control valves (16, 19) are closed and the transfer pipe (14) between the injector (15) and the first control valve (16) is filled with the powder coating material (5). After activating the quantitative supply means (7) as described above,
The first control valve (16), the second control valve (19), the work transfer means (1), and the fixed-rate supply means (7) so that the work transfer means (1) starts transferring the work (W) to be coated. 2. The apparatus according to claim 1, wherein the operation of the step (a) is controlled.