JPH0446821Y2 - - Google Patents

Description

[Detailed explanation of the idea]

[Industrial Application Field] The present invention is designed to control the thickness of the resin film to be applied by adjusting the thickness of the resin film to be coated on metal wires, particularly rectangular wires, by using the electrostatic flow dipping method. The present invention relates to an electrostatic powder coating apparatus that is provided with a coating film thickness adjustment mechanism that makes the thickness substantially uniform on each surface of the outer periphery and adjusts the coating thickness to a desired thickness. [Prior Art] An electrostatic flow dipping method is known as a method for continuously coating a metal wire with a resin film using a powder coating method. In this method, a grounded metal wire, which is the object to be coated, is run through a coating tank in which a cloud of particles of resin powder charged with static electricity is formed, and the resin powder is deposited on the wire. A coating film is formed by heating this and melting the resin powder. Therefore, when this method is applied to the coating of rectangular filaments such as rectangular insulated electric wires, the thickness of the coating film is different from the outer circumference of the filament as in the case of rectangular enameled electric wires painted using the conventional enamel coating method. It is not uniform on the surface, especially if the coating equipment is horizontal, and
There was a problem that there was a significant difference in the thickness of the bottom coating. Therefore, as a measure to improve this,
In the proposal for 8221, by installing a barrier board at a distance from the running position of the object streak in the coating tank, the amount of powder resin adhering to the streak at that location is adjusted. There is. Furthermore, in the proposal of JP-A-58-150218, the amount of powdered resin adhering to the streaks at that location is adjusted by bringing the board into direct contact with the streaks of the object being coated. ing. [Problem to be solved by the invention] However, if a barrier board is provided at a distance from the traveling position of the object to be painted, as in the proposal of the above-mentioned Japanese Patent Publication No. 55-8221, the thickness of the coating film It is difficult to adjust accurately, and if it is operated continuously for a long time, resin powder may accumulate on the top surface of the cutting board, form a lump, and fall off, resulting in a poor appearance of the coating film. There is. In addition, as in the proposal of JP-A No. 58-150218, when the board is brought into direct contact with the moving object filament, if the abutting point is on the lower surface of the filament, If the machine is operated for a long period of time, trace amounts of metal powder and foreign matter adhering to the surface of the striations will accumulate between the striations and the surface of the striations, causing damage to the surface of the striations or sticking to the striations. There is a problem in that it affects its operation. [Means for solving the problem] The present invention was devised to solve the above-mentioned problems in conventional electrostatic powder coating equipment. , also relates to an electrostatic powder coating device equipped with a coating film thickness adjustment mechanism that can always maintain a uniform coating thickness with high accuracy and adjust the coating thickness to a desired thickness. It is something. That is, the gist of the present invention is that a grounded metal wire is run through a coating tank in which a cloud of particles of resin powder charged with static electricity is formed, and the resin powder is deposited on the metal wire. In an electrostatic powder coating device for adhering resin powder to a metal wire body, the above-mentioned method is used as a means for uniformizing the thickness of the coating film of resin powder on the metal wire body and adjusting the coating film thickness to a desired thickness. A powder leveling brush is arranged around the metal wire running path in the coating tank so as to be in contact with the running metal wire, and a powder leveling brush is provided outside the coating tank and the powder leveling brush The electrostatic powder coating apparatus is characterized in that it includes a position moving arm that moves the coating tank to a position in the longitudinal direction. [Function] According to the electrostatic powder coating apparatus equipped with the coating film thickness adjustment mechanism of the present invention configured as described above, the coating thickness adjustment mechanism consisting of the powder leveling brush allows the coating material to be coated. Even in the case of rectangular metal wires, which are the most difficult to achieve a uniform coating thickness among metal wires, it is possible to properly remove the powder resin that adheres to the side where the coating thickness is thicker. Since it is leveled, the coating film on the outer peripheral surface can always be made uniform. Further, by providing an arm for moving the powder leveling brush in the longitudinal direction of the coating tank outside the coating tank, it is possible to adjust the thickness of the coating film. Further, by making the powder leveling brush cylindrical and rotating in the direction opposite to the running direction of the metal wire, the leveling action can be performed more effectively. [Embodiment of the invention] Next, an electrostatic powder coating apparatus of the invention will be described based on an embodiment shown in the drawings. Figure 1 is a cross-sectional view showing an example of a horizontal coating device used in the electrostatic flow dipping method, and Figures 2 and 3 are coating film thickness adjustment when leveling brushes of different shapes are installed. FIG. 3 is a perspective view of the main parts of the mechanism. Reference numeral 1 in the figure indicates a coating tank, and a porous plate 4 is provided inside the coating tank 1, and a powdered resin 9 is placed on the porous plate 4. Reference numeral 6 represents an electrode, to which a high DC voltage is applied by the high voltage electricity generator 5. Therefore, the dry air inlet 1 provided at the bottom of the coating tank 1
Dry air is sent from 0, and the powder resin 9 on the porous plate 4 is fluidized by this air, and at the same time, the powder particles are charged with the above DC high voltage, forming a particle cloud. Formed on a fluidized bed. 11 is an air outlet. Reference numeral 3 denotes a rectangular filament of the object to be coated, which is grounded and is configured to run through the particle cloud in the coating tank 1 in the direction shown by the arrow in the figure. Reference numeral 2 denotes a leveling brush for adjusting the thickness of the coating film, which is guided by a guide rail 7 as shown in the figure, and is placed around the running path of the rectangular filament 3. They are placed so that they are in contact with each other. Figure 2,
FIG. 3 shows another embodiment, in which the leveling brush 2 has a cylindrical shape. Reference numeral 8 denotes a position moving arm for the leveling brush 2, and the position of the leveling brush 2 can be changed from the outside of the coating tank 1. Next, the operation of the coating film thickness adjustment mechanism in the electrostatic powder coating apparatus of the present invention having the above configuration will be explained. To form an electrically insulating coating film by coating the powder resin 9 on the rectangular filament 3 of the object to be coated using the electrostatic flow dipping method, the rectangular filament 3 is grounded in the direction indicated by the arrow in the coating tank 1. is run, high-voltage electricity is sent from the high-voltage electricity generator 5 to the electrode 6, and at the same time dry air is sent from the dry air inlet 10. Then, this dry air causes the powdered resin 9 on the porous plate 4 to flow, giving charge to the powder particles and forming a particle cloud on the fluidized bed. Powder resin 9 adheres to the entire surface of the rectangular filament 3. Next, in a heating device for the next step (not shown), the powder resin 9 is heated to a temperature higher than its melting temperature to form a coating film. Next, this coating film is cooled and fixed onto the rectangular filament 3. In this case, the thickness of the coating film to be applied is determined by the amount of dry air sent into the fluidized bed and the voltage applied to the electrodes, but as it is, the powder resin 9 is thick on the bottom surface of the rectangular filament 3 and thin on the top surface. It is painted and the thickness of the flat and edge surfaces are also different. Therefore, in this proposal,
In order to make the thickness of the coating film uniform on all circumferential surfaces, flat surfaces, and edge surfaces, the powder resin 9 is coated with a leveling brush 2 placed in advance in direct contact with the areas where the coating film will be thick. The amount of adhesion can be adjusted. Further, by changing the position of the powder leveling brush 2 in the running direction of the metal wire 3 using the position moving arm 8, the coating film thickness can be adjusted. That is, if you want to thicken the coating film, use the powder leveling brush 2.
If you want to reduce the amount of powder resin 9 scraped off by the powder scraping brush 2 by moving the position of The amount of powder resin 9 scraped off by the powder leveling brush 2 may be increased by moving the position of the body leveling brush 2 to the exit side of the metal wire 3. In the case of the cylindrical brush 2 shown in FIG. 3, the effect becomes even more pronounced if it is rotated at a circumferential speed of about 1 to 5 m/min in the opposite direction to the running direction of the rectangular filaments 3. The material of the leveling brush 2 may be any material as long as it does not damage the lines of the object to be coated. The following Table 1 shows the results obtained using the electrostatic powder coating equipment shown in Figure 1, wire sizer: 2 x 8 mm copper rectangular wire, wire speed 9.
m/min, powder resin: epoxy (Sumitomo Duress,
EPC205), brush: Shows the results of an example in which painting was performed with nylon (fiber diameter 50μ x bristle length 10mm) and a proportional example in which the leveling brush 2 was not used.

[Effect of idea]

According to the electrostatic powder coating apparatus of the present invention, even if the metal filaments of the object to be coated are rectangular filaments, the coating film thickness is approximately uniform on each surface, and unlike the case of conventional apparatuses, the coating film thickness is approximately uniform on each surface. This prevents large differences in the coating thickness on the bottom surface or on both the left and right sides, and the coating thickness can be adjusted by adjusting the position of the metal wire of the powder leveling brush in the running direction. Thickness can be adjusted with high precision. Furthermore, since the leveling brush is in contact with the object to be painted, the object to be painted will not be scratched by scale or the like even during continuous operation for a long time.

[Brief explanation of the drawing]

Figures 1 to 3 show an embodiment of the present invention, with Figure 1 being a longitudinal cross-sectional view of a horizontal electrostatic powder coating apparatus equipped with the coating film thickness adjustment mechanism of the present invention, and Figures 2 and 3 showing an embodiment of the present invention. 3 are perspective views showing details of main parts of other embodiments of the coating film thickness adjustment mechanism. In the figure, numeral 1 is a coating tank, 2 is a leveling brush, 3
4 is a porous plate, 5 is a high-voltage electricity generator, 6 is an electrode, 7 is a guide rail, 8 is a rectangular wire to be coated.
9 is a position moving arm, 9 is a powder resin, 10 is a dry air inlet, and 11 is an air outlet.

Claims (1)

[Scope of Claim for Utility Model Registration] (1) A grounded metal wire is run through a coating tank in which a particle cloud of resin powder charged with static electricity is formed. In an electrostatic powder coating device that applies resin powder to a strip, in order to equalize the thickness of the resin powder coating on the metal strip and adjust the coating thickness to the desired thickness. As a means for this, a powder leveling brush is arranged around the metal wire running path in the coating tank so as to be in contact with the running metal wire, and a powder leveling brush is provided outside the coating tank to level the powder. An electrostatic powder coating apparatus comprising: a position moving arm for moving a leveling brush to a position in the longitudinal direction of the coating tank. (2) The electrostatic powder according to claim 1, wherein the powder leveling brush has a cylindrical shape and rotates in a direction opposite to the running direction of the filaments. Painting equipment.