JPH0515814A - Automatic electrostatic coater for powder - Google Patents

Abstract

PURPOSE:To prevent the lowering of coating efficiency of powder coating when increasing the travel speed of a spray gun by a reciprocator. CONSTITUTION:In the case where the speed of vertical motion of a spray gun 5 is high, before a mist cloud 16 of powder coating jetted from the nozzle 6 of the spray gun 5 reaches a substance to be coated 3, the electrostatic field between the spray gun 5 and the substance to be coated 3 disappears from the flight space of the mist cloud 16. The mist cloud 16 flies in the electrostatic field 15 formed so as not to move vertically between the substance to be coated 3 and an electrode 11 fixed close to a transfer route of the spray gun 5, causing it to be surely attracted by the substance to be coated 3.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a static transfer between a coating object conveyed in one direction by a conveyor and a coating gun which is reciprocally driven by a reciprocator in a direction perpendicular to the conveying direction of the coating object. The present invention relates to an electrostatic powder automatic coating apparatus in which an electric field is formed and powder coating material charged by a coating gun is attracted to an object to be coated by electrostatic attraction.

[0002]

2. Description of the Related Art In the electrostatic powder automatic coating apparatus as described above, the moving stroke of the coating gun becomes long when the convey speed of the conveyor is high or the size of the object to be coated is large. In this case, in order to prevent uneven coating, a means for increasing the moving speed of the coating gun is taken.

At this time, the electrostatic field formed between the coating gun and the object to be coated also moves at a high speed.
On the other hand, the speed at which the powder coating material ejected from the coating gun and forming a spray cloud flies toward the object to be coated is relatively slow.

Therefore, conventionally, when the moving speed of the coating gun is remarkably increased, the electrostatic field disappears from the flight space of the spray cloud before the spray cloud reaches the object to be coated, and the electrostatic field is adsorbed to the object to be coated. However, there is a problem that the amount of the powder coating material to be used decreases and the coating efficiency decreases.

The present invention was devised in view of the above circumstances, and an automatic electrostatic powder coating apparatus capable of moving a coating gun at high speed without lowering the coating efficiency. It is intended to provide.

[0006]

Means for Solving the Problems As a means for solving the above problems, the present invention provides an object to be coated which is conveyed in one direction by a conveyor, and a reciprocator which is perpendicular to the direction in which the object is coated. Electrostatic powder automatic coating device that forms an electrostatic field between the coating gun that is reciprocatingly driven by the robot and causes the powder paint charged in the coating gun to be attracted to the object to be coated by electrostatic attraction. , A plurality of electrodes with the same polarity as that of the coating gun are fixed in parallel in the vicinity of the moving path of the coating gun along the moving path of the coating gun, and the electrodes and the object to be coated are fixed. The configuration was such that an electric field was formed.

[0007]

According to the present invention having the above-mentioned structure, the powder coating material charged in the coating gun is ejected into the electrostatic field formed between the coating gun and the object to be coated to form a spray cloud. Fly towards the object to be painted.

At this time, an electrostatic field that does not move in the same direction as the moving direction of the coating gun is sprayed between the plurality of electrodes fixed in the vicinity of the moving path of the coating gun and the object to be coated. It is formed across the entire space in which clouds fly.

Therefore, even if the electrostatic field between the coating gun and the object to be coated disappears from the flight space of the coating cloud when the coating gun moves at high speed, the coating cloud still remains between the electrode and the coating object. The object to be coated is reliably reached by flying in the electrostatic field formed between them.

As explained by the above operation, the electrostatic powder automatic coating apparatus of the present invention can surely apply the powder coating material to the object to be coated even if the moving speed of the coating gun is high. effective.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the accompanying drawings. In the figure, reference numeral 1 indicates a conveyor that conveys the article 3 to be coated in a horizontal direction in a state of being suspended by a hook 2. A reciprocator 4 installed in a coating booth in the middle of the transportation route supports a coating gun 5 with a nozzle 6 oriented horizontally toward the object 3 to be coated through a bracket 7. The reciprocator 4 is driven to reciprocate in the vertical direction.

A powder coating material is supplied to the coating gun 5 from a coating material supply source (not shown). In the nozzle 6 of the coating gun 5, contact or friction with an electrode connected to a high voltage generator is prevented. By the action, the powder coating material is charged with the static electricity of the negative electrode, and the charged powder coating material is ejected toward the object to be coated 3.

On the other hand, the article to be coated 3 is a hook 2 and a conveyor 1.
Is grounded to the ground via the via, and thereby a high-potential electrostatic field is formed between the nozzle 6 of the coating gun 5 on the negative electrode side and the object 3 to be coated on the positive electrode side. ..

In the vicinity of the reciprocator 4, a vertically elongated stand 10 is fixedly installed.
A plurality of electrodes 11 are attached to the stand 10 in the vicinity of the moving path of the coating gun 5 and in parallel with the moving path at a predetermined interval. Each electrode 11 is
It is connected to a high voltage generator 13 via a high voltage cable 12 so that a negative voltage having the same voltage value as that of the coating gun 5 is applied.
An electrostatic field 15 is formed between the electrode 11 and the portion of the object to be coated 3 that is substantially the same in height as the electrode 11.

The present embodiment has the above-mentioned structure, and when the object 3 to be coated is conveyed in front of the coating gun 5, the powder paint is sprayed from the nozzle 6 of the coating gun 5 which moves up and down by the drive of the reciprocator 4. Are sprayed in a charged state, and the sprayed powder coating is atomized by the repulsive force between the negative charges, and the spray cloud 1
6 and fly toward the object 3 to be coated on the positive electrode side in the electrostatic field at a relatively slow speed due to the electrostatic attraction force.

At this time, as the coating gun 5 moves, the electrostatic field formed between the coating gun 5 and the object to be coated 3 also moves vertically, but when the coating gun 5 moves slowly. First, the spray cloud 16 is attracted to a predetermined height portion of the object 3 to be coated by flying in the electrostatic field between the coating gun 5 and the object 3 to be coated.

On the other hand, when the moving speed of the coating gun 5 is high, the electrostatic field between the coating gun 5 and the object to be coated 3 also moves up and down at a high speed.
Before it reaches the object to be coated 3, the spray cloud 16 disappears from the space in which it flies. However, between the electrode 11 provided in the vicinity of the movement path of the coating gun 5 and the object 3 to be coated, there are a plurality of electrostatic fields 15 held in a space of a constant height regardless of the movement of the coating gun 5. Since the spray cloud 16 exists over the entire moving path of the coating gun 5, the spray cloud 16 flies in the electrostatic field 15 between the electrode 11 and the object 3 to be coated so that a predetermined amount of the object 3 to be coated can be obtained. Reach the part.

Therefore, even when the speed of the coating gun 5 is high, the powder coating material is surely adsorbed to the article 3 to be coated, and good powder electrostatic coating is performed.

[Brief description of drawings]

FIG. 1A is a side view.

FIG. 1 (B) is a plan view.

[Explanation of symbols]

1: Conveyor 3: Object to be coated 4: Reciprocator
5: Coating gun 11: Electrode 15: Electrostatic field (between electrode and object to be coated)

Claims (1)

Claim: What is claimed is: 1. An object to be coated which is conveyed in one direction by a conveyor, and a coating gun which is reciprocally driven by a reciprocator in a direction perpendicular to the direction in which the object is conveyed. In an electrostatic powder automatic coating device that forms an electrostatic field and causes the powder coating material charged in the coating gun to be attracted to the object to be coated by electrostatic attraction, In the vicinity, a plurality of electrodes having the same polarity as the coating gun are fixed in parallel along the moving path of the coating gun, and an electrostatic field is formed between the electrodes and the object to be coated. Characteristic electrostatic powder automatic coating device.