JPS6160919B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a method and apparatus for manufacturing an electrically insulated conductor, and more particularly to a method and apparatus for manufacturing an electrically insulated conductor by electrodepositing a fringe material onto an electrical conductor using electrophoresis. be. The principle of this type of technology is as shown in Figure 1.
A water-based acrylic electrodeposition paint 2 is placed in an electrodeposition tank 1, a conductive object 3 is immersed in the electrodeposition paint 2, and a DC voltage is applied using the object 3 as an anode and the electrodeposition tank 1 as a cathode. E is applied to form an electrodeposited film on the surface of the object 3 to be coated. Here, as the object 3 to be coated, a hexagonal conductor is used as shown in the figure. In this method and apparatus for producing an electrically insulated conductor, when an electrodeposited insulating layer is formed using an electrodeposited paint consisting of mica powder and water-dispersed varnish, which the present inventors have already proposed, the mica powder settles, so the electrical It is necessary to constantly stir the applied paint to prevent the mica from settling and maintain a uniform state of mixing of the water-dispersed varnish and mica powder. On the other hand, stirring an electrodeposition paint made of mica powder and water-dispersed varnish is preferable because the flow of the electrodeposition paint is a gentle laminar flow with a uniform velocity regardless of the water depth, but in reality, the flow speed may differ depending on the water depth. Therefore, it is difficult to obtain a completely laminar flow, and in the end, a constant flow including turbulent flow for stirring is preferable. Fig. 2 shows the conventional stirring method of the electrodeposition paint in the electrodeposition tank using such an electrodeposition paint, in which a mainstream is formed at the bottom and one side of the electrodeposition tank 1 as indicated by the arrow A. A first partition plate 4 is provided, this partition plate 4 is provided with a nozzle 5, and the object to be coated 3 is positioned in front of the nozzle 5. Reference numeral 6 denotes a second partition plate, which is provided opposite to the partition plate 4 and is provided with an outlet 7. The pump 8 is a pump for circulating the electrodeposition paint 2 from the main flow through the nozzle 5 and the outlet 7. In this case, nozzle 5
If the flow rate is too low, the mica powder will settle, but if the flow rate is too high, the component ratio of the electrodeposited film will be different from that of electrodeposition paint 2, and good electrodeposition will not be obtained. Therefore, a flow in the direction shown by arrow B, which is opposite to the main flow, is applied near the bottom of the first partition plate to stir the mica powder and prevent the mica powder from settling. However, in such a conventional method, the flow indicated by arrow B flows in the same direction as the main flow, accelerating the flow velocity at the liquid surface. Also,
When the object to be coated 3 is a complex-shaped conductor, the electrodeposited film formed on the conductor surface may vary between the part facing the flow of the electrodeposited paint and the part in the shadow. There were some problems that occurred. This invention was made with attention to the above points, and the water-dispersed varnish and mica powder of the electrodeposition paint in the electrodeposition bath are uniformly dispersed, there is no sedimentation of the mica powder, and further, the formation of The object of the present invention is to realize a method for manufacturing an electrically insulated conductor in which the thickness and composition of the electrodeposited film are uniform and good. Another object of the present invention is to make the flow of the electrodeposition paint in the electrodeposition tank a constant laminar flow at the position of the object to be coated, to create a turbulent flow that prevents the mica powder from settling, and to make the electrodeposition film uniform. An object of the present invention is to provide an apparatus for producing an electrically insulated conductor. Hereinafter, the present invention will be explained with reference to embodiments of the drawings. In one embodiment of FIG. 3, in the electrodeposition bath 11,
A first partition plate 14 forming a main flow path indicated by an arrow P is provided along the bottom wall 11a and one side wall 11b.
Equipped with. Reference numeral 16 denotes a second partition plate, which is disposed so as to form a circulation path shown by an arrow R along the side wall 11c opposite to the side wall 11b.
a is located below the liquid level of the electrodeposition paint 12. 1
Reference numeral 9 denotes a turning plate which is fixed to the partition plate 14 and reverses the stirring flow path shown by the arrow Q flowing in the same direction as the main stream along the bottom 14a of the first partition plate 14 in the opposite direction. The first and second pumps 18a and 18b are
Water is taken from the reflux path R to create a main flow path P and a stirring flow path Q, respectively. The object to be coated 13 is suspended in front of the nozzle 15 parallel to the flow of the main flow path. When forming an electrodeposition film, the electrodeposition paint discharged from the nozzle 15 forms a certain laminar flow at the position of the object 13 to be coated, and then passes above the upper edge 16a of the second partition plate 16. Water intake 20 via return channel R
to pumps 18a and 18b. pump 18a
sends the electrodeposition paint to the nozzle 15 again, and pump 1
8b sends the electrocoating paint to the stirring channel Q parallel to the main channel P, but this stirring channel Q is reversed by the turning plate 19 and gradually moves upward after passing the position of the object 13 to be coated. It merges with the main flow of the water and reaches the reflux path R.
At this time, the flow reversed by the turning plate 19 does not accelerate the flow velocity in the main flow path P, but has the effect of promoting the flow in a region where the flow speed in the main flow path P is weak. A satisfactory stirring effect is thus achieved with a constant laminar flow at the location of the workpiece. In the above case, the mainstream flow velocity of the electrodeposition paint is 3 m/
A range of min to 10 m/min is preferred. In addition, when the object to be coated is a hexagonal conductor, the object to be coated 13 is set parallel to the main channel P of the electrodeposition paint, as shown in FIG. From the state where object 13 is shown as a solid line with respect to the vertical line
By rotating it 180 degrees and performing electrodeposition as shown by the broken line, there is less variation in the electrodeposited film between the part facing the flow of the main channel P and the shaded part.
An electrodeposited film of uniform thickness can be applied. Furthermore, the process of forming an electrodeposited film on these electrical conductors can be automated. Referring to the process schematic diagram in FIG. An arm 23 is adjacent to a gripping device 22 that lifts, lowers, and rotates the object 13 to be coated.
The object to be coated 13 transferred by the conveyor 21 is caught by the gripping device 22, and
1 is separated and hangs down and immersed in the electrodeposition paint 12 as shown by the chain line. After dipping, the electrodeposition tank 11 and the object to be coated 1
3, a DC voltage is applied by the power supply device 24 for the necessary time. At this time, in the middle of the progress of electrodeposition, the application of the DC voltage is temporarily stopped, and the object 13 to be coated, which is gripped by the gripping device 22, is rotated by 180 degrees with respect to the vertical line.
The voltage is applied again to perform electrodeposition, and after the electrodeposition is completed, the object 13 to be coated is again rotated 180 degrees to return to its original state, pulled up, and transferred to the conveyor 21. In this case, the automated equipment may be of any known automation technology. The table below provides data for various examples.

[Table] That is, in Example 1, 90 parts by weight of mica powder was mixed with 10 parts by weight of the resin content of the water-dispersed varnish, and 15% non-volatile content electrodeposition was added to the electrodeposition bath with ion-exchanged water. A coating material was prepared. This electrodeposition paint
When a DC voltage of 100V was applied for 12 seconds to a tortoiseshell-shaped object with a constant flow rate of 8m/min,
It was rotated 180° and voltage was applied again for 12 seconds in the same manner, indicating that an electrodeposited film with a thickness of 1.0 mm was formed. In Examples 1, 2, and 3, the electrodeposited films had a uniform composition and thickness, without being different from the liquid composition of the electrodeposition paint.

[Brief explanation of the drawing]

Fig. 1 is a diagram of the principle of electrodeposited film formation, Fig. 2 is a schematic diagram of the prior art, Fig. 3 is a schematic diagram of an embodiment of the present invention, and Fig. 4 also shows the rotation of the object to be coated. FIG. 5 is a schematic diagram of another embodiment. 11: Electrodeposition tank, 12: Electrodeposition paint, 13: Object to be coated, 14: First partition plate, 15: Nozzle, 16:
Second partition plate, 18a, 18b: first and second pumps, 19: turning plate, 21: conveyor, 22: gripping device, 23: arm, 24: power supply device.

Claims (1)

[Scope of Claims] 1 A conductor to be coated is immersed in an electrodeposition paint containing a water-dispersible varnish and mica powder dispersed in water, which is housed in an electrodeposition bath, and becomes one electrode and the other electrode. In the method for manufacturing an electrically insulated conductor, the electrodeposited film is formed on the object by applying a DC voltage between the electrodeposition tank and the electrodeposition tank. Form a flow path, and use the first flow path below as the main flow path at the position of the object to be coated at 3 m/min to 10 m/min.
A constant velocity laminar flow is applied, and the upper second flow path is used as a stirring flow path and reversed below the position of the object to be coated to merge with the main flow path that has passed through the position of the object to be coated, and to cause reflux. A method for manufacturing an electrically insulated conductor, characterized in that the electrodeposition film is formed by rotating the object to be coated at a certain angle with respect to a vertical line at an intermediate point in the progress of electrodeposition. 2. The method for producing an electrically insulated conductor according to claim 1, wherein the object to be coated is rotated at a rotation angle of approximately 180°. 3. A method for producing an electrically insulated conductor according to claim 1, wherein the steps up to the completion of forming the electrodeposited film are automatically performed. 4. A coated object made of an electrical conductor is immersed in an electrodeposition paint containing a water-dispersible varnish and mica powder dispersed in water, which is housed in an electrodeposition bath, to form one electrode, and the electrodeposition to become the other electrode. In an apparatus for manufacturing an electrically insulated conductor that forms an electrodeposited film on the object by applying a DC voltage between the electrodeposition tank and the electrodeposition tank, a main channel is formed between the electrodeposition tank and the bottom surface of the electrodeposition tank, and the electrodeposition film is formed on the side of the electrically insulated conductor. a first partition plate including a nozzle in the main flow path that provides a constant velocity laminar flow to the position of the coating material; and a second partition plate that forms a return flow path between the other side wall facing the side wall; a turning plate for reversing the stirring flow path along the bottom of the first partition plate so that it merges with the main flow path passing through the object to be coated; An apparatus for manufacturing an electrically insulated conductor, comprising means for rotating a coating material at a fixed angle with respect to a vertical line. 5. The electrically insulated conductor manufacturing apparatus according to claim 4, further comprising first and second pump means between the reflux path and the main flow path and between the reflux path and the stirring flow path, respectively.