Fluidized dip coating device and method for manufacturing wiring member having insulating coating

Abstract

To provide a fluid-soaking and coating apparatus which uses a powdered paint and can suppress deposition of the powdered paint more than necessary to a coating object body.SOLUTION: A fluid-soaking and coating apparatus 100 includes a fluid tank 10 and a conveyance unit 20. The fluid tank 10 fluidizes a powdered paint 13 in the fluid tank 10. The conveyance unit 20 includes a support housing 21, a lift driving unit 23 which is provided in the support housing 21, a shaking-off driving unit 24 and a conveyance jig holding unit 25. The lift driving unit 23 is held by the conveyance jig holding unit 25, lowers a conveyance jig 27 suspending the coating object body 30 to the fluid tank 10 to immerse the coating object body 30 in the powdered paint 13, and lifts it up to the upper part of the fluid tank 10. The shaking-off driving unit 24 vibrates the conveyance jig 27 in the vertical direction, applies the acceleration alternately in the upper direction and lower direction to the coating object body 30, and can shake off the powdered paint 13 deposited more than necessary to the coating object body 30.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present disclosure relates to a fluidized bed dip coating apparatus and a method for manufacturing a wiring member having an insulating coating using the same. [Background technology]

[0002] Conventionally, insulated bus bars, each having a plate-shaped conductor made of a conductive material and an insulating layer disposed on the conductor, have been used as wiring components for transmitting current within power conversion devices such as inverters and converters. A known method for manufacturing insulated bus bars involves fluidized bed coating, in which a powder coating material such as a thermosetting resin is fluidized by injecting compressed air through a porous partition wall at the bottom of a bath containing the powder coating material. The insulating layer is formed by immersing the conductor in the fluidized bed coating (see, for example, Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent Publication No. 2021-48001 Summary of the Invention [Problem to be solved by the invention]

[0004] Patent Document 1 describes a method for manufacturing an insulated busbar, in which a preheated conductor is immersed in a powder coating material flowing in a tank to coat the outer periphery of the conductor with the powder coating material, and then the coated powder coating material is hardened by heat treatment to form an insulating layer on the outer periphery of the conductor. It also describes that the amount of powder coating applied to the conductor can be made uniform by changing the immersion direction of the conductor in the tank every time the conductor is immersed.

[0005] However, when the conductor is pulled out of the powder paint tank, excessive powder paint accumulates on the top surface of the conductor and in the mounting holes of the conductor. If heat treatment is performed to harden the conductor in this state, there are issues such as the molten paint dripping and the hardened paint blocking the mounting holes.

[0006] The present disclosure has been made in light of the above-mentioned problems, and aims to provide a fluidized bed dip coating device that can prevent excessive accumulation of powder paint on the upper end of a workpiece or inside a mounting hole when applying powder paint to workpieces of various shapes using fluidized bed dip coating. [Means for solving the problem]

[0007] The fluidized bed coating apparatus according to the present disclosure includes a support housing having a conveying jig holding unit, a fluidization tank for fluidizing powder paint, a conveying jig held by the conveying jig holding unit and suspending an object to be coated above the fluidization tank, and a lifting drive unit provided on the support housing, which lowers the transport jig until the object to be coated is immersed in the fluidization tank and lifts the object to be coated out of the fluidization tank; and a lifting section of the lifting drive unit. Established in The lifting drive unit lifts and lowers the conveying jig and the object to be coated together, Vibrate the transport jig vertically It is the shake-off drive unit. The first driving section is provided.

[0008] A method for manufacturing an electrical conductor having an insulating coating according to the present disclosure includes: (a) heating the electrical conductor at a first temperature; and (b) after step (a), By the lift drive unit (c) a step of lowering the conductor from above the fluidized bed in which the powder paint is flowing, immersing it in the powder paint, and adhering the powder paint to the conductor; and (c) after the step (b), By the lift drive unit and lifting the conductor from the powder coating and applying acceleration to the conductor alternately in an upward and downward direction. The application of acceleration to the conductor in step (c) is performed by a shake-off drive unit that is provided in the lifting portion of the lifting drive unit, which lifts and lowers the object to be coated together with the transport jig that suspends the object to be coated, and vibrates the transport jig in the vertical direction. It has characteristics. [Effects of the Invention]

[0009] The fluidized bed dip coating device disclosed herein is capable of immersing an object to be coated in a fluidized bed of powder paint, then lifting it up, and then applying alternating upward and downward acceleration to the object to lift it up from the fluidized bed and lower it back down into the fluidized bed. This shakes off any excess powder paint that has accumulated, preventing drooling of molten paint during heat treatment for curing and preventing the cured paint from clogging the mounting holes. [Brief explanation of the drawings]

[0010] [Figure 1] 1 is a front view showing the appearance of a fluidized bed dip coating apparatus 100 according to the first or second embodiment. [Figure 2] 1 is a side view showing the appearance of a fluidized bed dip coating apparatus 100 according to the first or second embodiment. [Figure 3] 1 is a perspective view showing the appearance of a wiring member 32A having an insulating coating produced using a fluidized bed dip coating apparatus 100 according to the first or second embodiment. [Figure 4] 1 is a flowchart S100 showing a method for manufacturing a wiring member having an insulating coating according to the first embodiment. [Figure 5] 10 is a perspective view showing the manufacturing process of step S101 or S201 of the manufacturing method for a wiring member having an insulating coating according to the first or second embodiment. FIG. [Figure 6] 10 is a perspective view showing the manufacturing process of step S102 or S202 of the manufacturing method of the wiring member having an insulating coating according to the first or second embodiment. FIG. [Figure 7] 10 is a front view showing the manufacturing process of step S103 or S203 of the manufacturing method for a wiring member having an insulating coating according to the first or second embodiment. FIG. [Figure 8] 10 is a front view showing the manufacturing process of step S105 or S205 of the manufacturing method for a wiring member having an insulating coating according to the first or second embodiment. FIG. [Figure 9] 10 is a front view showing a manufacturing process of step S106 of the manufacturing method for a wiring member having an insulating coating according to the first embodiment. FIG. [Figure 10]10 is a front view showing the manufacturing process of step S107 or S207 of the manufacturing method for a wiring member having an insulating coating according to the first or second embodiment. FIG. [Figure 11] 7 is a cross-sectional view of the conductor 30A shown in FIG. 6 taken along line XX immediately before being placed in a heat treatment furnace in step S109 in the case where step S107 of the method for manufacturing a wiring member having an insulating coating according to the first embodiment is not performed. FIG. [Figure 12] 7 is a cross-sectional view of the conductor 30A shown in FIG. 6 taken along the line XX immediately before being placed in a heat treatment furnace in step S109 in the method for producing a wiring member having an insulating coating according to the first embodiment. FIG. [Figure 13] 10 is a flowchart S200 showing a method for manufacturing a wiring member having an insulating coating according to the second embodiment. [Figure 14] FIG. 11 is a front view showing a manufacturing process of step S206 in the manufacturing method of a wiring component having an insulating coating according to the second embodiment. [Figure 15] 7 is a cross-sectional view of the conductor 30A shown in FIG. 6 taken along the line XX immediately before being placed in a heat treatment furnace in step S209 in the method for producing a wiring member having an insulating coating according to the second embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0011] Embodiment 1 FIG. 1 is a front view showing the appearance of a fluidized bed dip coating apparatus 100 according to the first embodiment. FIG. 2 is a side view showing the appearance of the fluidized bed dip coating apparatus 100 according to the first embodiment. The fluidized bed dip coating apparatus 100 is composed of a fluidizing tank 10 and a conveying unit 20. The fluidizing tank 10 has a perforated plate 12 with a plurality of holes 11 formed in the lower part of the fluidizing tank 10. The fluidizing tank 10 can fluidize the powder coating material 13 contained in the fluidizing tank 10 by introducing compressed gas 14 from the underside of the perforated plate 12 toward the powder coating material 13 contained in the fluidizing tank 10. Here, the gas 14 is, for example, air or an inert gas.

[0012] Furthermore, the transport unit 20 has a support housing 21, a support column 22, an elevation drive unit 23, a shake-off drive unit 24, and a transport jig holder 25. The transport jig holder 25 is provided in the support housing 21, and holds a transport jig 27, which is suspended from the object 30 to be coated using a suspender 26, so that the transport jig 27 does not fall. Furthermore, the transport jig holder 25 can detachably hold the transport jig 27.

[0013] 1 and 2, the conveying section 20 is installed so that a conveying jig 27 held by a conveying jig holding section 25 can be positioned above the flow bath 10. In FIGS. 1 and 2, as an example, a single linear-shaped object to be coated 30 is hung from the conveying jig 27, but this is not limiting and multiple objects to be coated having the same shape or multiple objects to be coated having different shapes may also be used.

[0014] The lifting / lowering drive unit 23 is provided on the support housing 21. The lifting / lowering drive unit 23 can lower a transport jig 27 disposed above the fluidizing tank 10 toward the fluidizing tank 10 and then lift the lowered transport jig 27 above the fluidizing tank 10. The lifting / lowering drive unit 23 is, for example, a lifting actuator.

[0015] The shake-off drive unit 24 is provided in the support housing 21. In order to shake off excess powder paint 13 accumulated on the object 30, the shake-off drive unit 24 can vibrate the transport jig 27 up and down at short intervals while the lift drive unit 23 has lowered the transport jig 27 to a height where the object 30 does not come into contact with the powder paint 13 in the fluidized bed 10. Furthermore, by vibrating the transport jig 27 up and down, the object 30 can be vibrated up and down via the suspender 26.

[0016] In other words, by driving the shake-off drive unit 24, the transport jig 27 is vibrated in the vertical direction, and acceleration in the vertical direction can be applied to the object 30 to be coated alternately in the upward and downward directions via the suspender 26. The shake-off drive unit 24 is, for example, a shake-off actuator. Here, the shake-off drive unit 24 is not necessarily required, and the lift drive unit 23 may vibrate the transport jig 27 in the vertical direction at short intervals in addition to lowering and raising the transport jig 27 toward the fluidizing bath 10. Here, the vertical direction refers to the direction in which the transport jig 27 is raised upward from the fluidizing bath 10 and the direction in which it is lowered into the fluidizing bath 10.

[0017] The powder coating material 13 used in fluidized bed dip coating by the fluidized bed dip coating apparatus 100 can be a thermosetting coating material or a thermoplastic coating material. When the powder coating material 13 is a thermosetting coating material, for example, a coating material using epoxy, polyester, epoxy polyester, acrylic, or the like as a base resin is used. When the powder coating material 13 is a thermoplastic coating material, for example, a coating material using vinyl chloride, polyethylene, nylon, saturated polyester, or the like as a base resin is used.

[0018] 3 shows, as an example of an object 30 to be coated in the first embodiment, a wiring member 32A in which an insulating coating 31A is provided on a conductor 30A by fluidized bed dip coating using a fluidized bed dip coating apparatus 100. That is, the wiring member 32A has an insulating coating 31A formed on the surface of the conductor 30A by fluidized bed dip coating using the fluidized bed dip coating apparatus 100. The thickness of the insulating coating 31A needs to be changed depending on the voltage applied to the wiring member 32A, and the insulating coating 31A may have a thickness of, for example, 0.1 mm to 3 mm.

[0019] The wiring member 32A is used, for example, as a wiring member that conducts large amounts of current in a distribution board or a control panel. However, the use of the wiring member 32A is not limited to this. Furthermore, the terminal portion 33A of the wiring member 32A, which is the portion that connects to another terminal, is provided with a terminal portion mounting hole 34A. Furthermore, the insulating coating portion provided with the insulating coating 31A is provided with an insulating coating portion mounting hole 35A. For example, a bolt can be passed through the terminal portion mounting hole 34A, the insulating coating portion mounting hole 35A, or both the terminal portion mounting hole 34A and the insulating coating portion mounting hole 35A to secure the wiring member to the distribution board or the control panel.

[0020] In the first embodiment, a straight-line wiring member 32A is shown as an example of a wiring member, but since wiring member 32A is formed to fit the size and wiring path of a switchboard or control panel, it may have various shapes, such as multiple bent portions. In addition, the material used for conductor 30A is, for example, copper, aluminum, or an alloy or clad material mainly composed of copper or aluminum.

[0021] Fig. 4 shows a flowchart S100 illustrating a method for manufacturing a wiring member having an insulating coating in embodiment 1. Figs. 5 to 10 show the manufacturing process of wiring member 32A in the main steps of flowchart S100. Here, a method for manufacturing wiring member 32A when using a thermosetting paint or a thermoplastic paint as powder paint 13 will be described. The main difference between the manufacturing methods when using a thermosetting paint and when using a thermoplastic paint is the heat treatment step; when using a thermoplastic paint, the heat treatment step S109 for hardening is not required.

[0022] First, in step S101, a surface preparation is performed, such as removing oil and dirt adhering to the surface of the conductor 30A shown in Fig. 5. Next, in step S102, as shown in Fig. 6, a masking member 36 is provided on the conductor 30A after the surface preparation to prevent the powder coating material 13 from adhering to the terminal portions 33A provided at both ends of the conductor 30A. Here, the masking member 36 is, for example, a heat-resistant film or sheet.

[0023] In step S103, as shown in FIG. 7, the conductor 30A provided with the masking member 36 is suspended from a transport jig 27 using a suspender 26. The transport jig 27 is a heat-resistant member having sufficient rigidity to suspend a coating object 30 such as the conductor 30A. The transport jig 27 also has a connecting portion that connects the suspender 26. The conductor 30A is suspended from the transport jig 27 by the suspender 26, and can swing around the connecting portion of the transport jig 27 as a base point. The connecting portion is not shown in FIG. 7.

[0024] Next, in step S104, in order to preheat the conductor 30A suspended from the transport jig 27, the conductor 30A is placed in a heat treatment furnace and heated. Here, the conductor 30A is placed in the heat treatment furnace together with the transport jig 27 while suspended from the suspender 26, for example. A diagram showing the heat treatment process in step S104 is omitted.

[0025] The time for preheating the conductor 30A is, for example, the time until the conductor 30A reaches the same temperature as the temperature inside the heat treatment furnace. If the powder coating 13 is a thermosetting coating, the temperature inside the heat treatment furnace for preheating is approximately 100°C to 200°C, which is higher than the melting point of the powder coating 13. If the powder coating 13 is a thermoplastic coating, the temperature is approximately 200°C to 300°C. The temperature inside the heat treatment furnace to which the conductor 30A is heated for preheating is the first temperature recited in the claims.

[0026] Next, the conductor 30A that has been heated to a temperature equivalent to that inside the heat treatment furnace is removed from the heat treatment furnace, and the transport jig 27 is held by the transport jig holder 25 provided in the transport section 20 of the fluidized bed dip coating apparatus 100. Then, in step S105, the conductor 30A suspended from the transport jig 27 is transported above the fluidized bed tank 10, as shown in FIG. 8. In other words, the conductor 30A suspended from the transport jig 27 is placed above the fluidized bed tank 10.

[0027] Next, in step S106, as shown in Figure 9, the lifting drive unit 23 provided on the support housing 21 of the transfer unit 20 of the fluidized bed dip coating apparatus 100 is driven to lower the conductor 30A to a height where it is fully immersed in the fluidized bed powder paint 13 in the fluidized bed tank 10. The conductor 30A is then immersed in the powder paint 13 for a preset time, thereby adhering the powder paint 13 to the conductor 30A. Here, by setting the immersion time, which is the time for which the conductor 30A is immersed and remains in the powder paint 13, to 10 seconds or less, it is possible to shake off excess powder paint 13 in the next process, step 107.

[0028] After immersing the conductor 30A in the powder paint 13, in step S107, the lifting drive unit 23 is driven to lift the conductor 30A, as shown in Fig. 10. The height to which the conductor 30A is lifted is set so that the conductor 30A does not come into contact with the powder paint 13 within the fluidization tank 10. By keeping the conductor 30A within the fluidization tank 10 in this way, it is possible to prevent the powder paint 13 shaken off the conductor 30A from leaking out of the fluidization tank 10.

[0029] Furthermore, in step S107, the shake-off drive unit 24 provided on the support housing 21 of the transport unit 20 of the fluidized bed dip coating apparatus 100 is driven to move the transport jig 27, from which the conductor 30A is suspended, alternately upward and downward multiple times in a short cycle. That is, by vibrating the transport jig 27 vertically, the conductor 30A is vibrated vertically via the suspending device 26. In other words, by driving the shake-off drive unit 24, the transport jig 27 is vibrated vertically, and acceleration is applied alternately upward and downward to the conductor 30A via the suspending device 26. Here, the upward direction refers to the direction in which the transport jig 27 is pulled upward from the fluidized bed 10, and the downward direction refers to the direction in which the transport jig 27 is lowered into the fluidized bed 10.

[0030] Here, by applying an acceleration of, for example, 8 to 12 G to the conductor 30A in the upward and downward directions, the excess powder paint 13 accumulated on the conductor 30A can be lifted up and shaken off. The number of times that the conductor 30A is vibrated in the up and down directions is, for example, 8 to 12 times. Here, each upward and downward movement is counted as one vibration.

[0031] Furthermore, the more times the conductor 30A is vibrated up and down, the more excess powder paint 13 can be shaken off. However, if the number of times is too many, the temperature of the conductor 30A will drop, and when the conductor 30A is again immersed in the powder paint 13 in the fluidized bed 10, the powder paint 13 will not adhere to the conductor 30A. Therefore, it is advisable to set the number of times the conductor 30A is vibrated up and down taking into account the temperature drop of the conductor 30A.

[0032] Furthermore, it is preferable to use, for example, a heat-resistant rod-shaped member such as a metal rod or wire with a diameter of 1 mm to 9 mm, a strip-shaped member such as a metal ribbon, or a combination of a rod-shaped member and a strip-shaped member as the suspender 26. By using such a member as the suspender 26, the suspender 26 can be deflected by vertically vibrating the transport jig 27, thereby increasing the acceleration applied to the conductor 30A. This improves the effectiveness of shaking off excess powder paint 13 accumulated on the conductor 30A.

[0033] Up to this point, it has been explained that in step S107, the conductor 30A is vibrated in the vertical direction, thereby applying acceleration alternately in the upward and downward directions to the conductor 30A, thereby shaking off the excess powder paint 13. However, this is not limiting, and for example, even when the conductor 30A is vibrated in an oblique vertical direction that is an angle relative to the vertical direction, vertical acceleration can be applied by a component force, making it possible to shake off the excess powder paint 13.

[0034] Also, in step S107, the shake-off drive unit 24 in the transport unit 20 of the fluidized bed dip coating apparatus 100 is driven to apply acceleration to the conductor 30A in the vertical direction. However, this is not limiting, and for example, acceleration may be applied alternately in the upward and downward directions to the conductor 30A by vibrating the transport jig 27 in the vertical direction using the lift drive unit 23 that raises and lowers the transport jig 27.

[0035] Next, in step S108, it is confirmed whether a preset number of dipping times has been reached. The preset number of dipping times is set in advance as the number of dipping times at which the coating film 40 formed by adhering the powder coating material 13 to the surface of the conductor 30A has a required thickness. The number of dipping times is set using previously obtained data showing the relationship between the number of dipping times and the thickness of the coating film 40. The number of dipping times is counted each time step S106 is performed. Here, the thickness of the coating film 40 can be measured, for example, by cutting the conductor 30A after dipping and observing the cross section.

[0036] In step S108, if the number of immersions has not reached the preset number of immersions, the process returns to step S106 along the No arrow in flowchart S100, and the conductor 30A is again immersed in the powder paint 13 in the fluidization tank 10. On the other hand, if the number of immersions has reached the preset number of immersions, the process of attaching the powder paint 13 to the conductor 30A is terminated, and the process proceeds to the next process, step S109, along the Yes arrow in flowchart S100.

[0037] In step S109, the conductor 30A is placed in a heat treatment furnace and heated in order to melt and harden the coating film 40. Here, a diagram showing the heat treatment step in step S109 is omitted.

[0038] In step S109, the conductor 30A having the coating film 40 formed by adhering the powder coating material 13 suspended from the transport jig 27 is heated in a heat treatment furnace to harden the coating film 40, thereby forming the insulating coating 31A. Here, the conductor 30A is kept in the heat treatment furnace until the coating film 40 hardens, and is removed from the heat treatment furnace after the hardening time has elapsed.

[0039] In the case of a thermosetting paint, the temperature in the heat treatment furnace for hardening the coating film 40 is preferably 160°C to 190°C. Here, the temperature in the heat treatment furnace for hardening the coating film 40 is the second temperature described in the claims. Furthermore, when a thermoplastic paint is used, the temperature of the coating film 40 drops, it cools and hardens to form a coating film, and it functions as the insulating coating 31A, so no heat treatment for hardening is required.

[0040] After confirming that the coating film 40 formed on the conductor 30A has hardened, in step S110, the masking members 36 provided on the terminal portions 33A provided on both ends of the conductor 30A are removed. This makes it possible to manufacture the wiring member 32A shown in FIG. 3, which has the insulating coating 31A in areas other than the terminal portions 33A.

[0041] Next, the effects of the method for manufacturing a wiring member having an insulating coating according to embodiment 1 will be described with reference to Figures 11 and 12. Figure 11 shows a cross-sectional view of part XX shown in conductor 30A in Figure 6 immediately before being placed in a heat treatment furnace in step S109, in the case where step S107 in flow chart S100 is not performed.

[0042] 11, powder coating material 13 softened or melted by the preheated conductor 30A adheres to the surface of conductor 30A, forming coating film 40A. Furthermore, more powder coating material 13 than necessary for coating film 40A adheres in powder form to the inside of insulating coating mounting hole 35A and on top surface 37A of the conductor. If the process proceeds to step S109 in this state and the product is placed in a heat treatment furnace to harden coating film 40A, problems such as sagging of the coating due to the excess powder coating material 13 melting and becoming fluid, or the hardened coating clogging insulating coating mounting hole 35A, may occur.

[0043] 12 shows a cross-sectional view of the conductor 30A in FIG. 6 taken along line XX immediately before being placed in a heat treatment furnace in step S109 after step S107 in flow chart S100 has been performed. As shown in FIG. 12, the coating film 40B formed on the surface of the conductor 30A is able to shake off excess powder paint 13 adhering to the inside of the insulating coating mounting hole 35A and the top surface 37A of the conductor 30A by applying acceleration alternately upward and downward in step S107. This prevents problems such as sagging of the powder paint due to excess powder paint 13 melting and becoming fluid, or blocking of the insulating coating mounting hole 35A with hardened paint.

[0044] As shown in Figures 1 and 2, fluidized bed dip coating apparatus 100 in the first embodiment is composed of fluidization tank 10 and conveying unit 20. Conveying unit 20 also has support housing 21, support columns 22, lifting / lowering drive unit 23, shake-off drive unit 24, and conveying jig holder 25. Shaking-off drive unit 24 can vibrate conveying jig 27 up and down at short intervals in order to shake off excess powder paint 13 accumulated on workpiece 30.

[0045] That is, fluidized bed dip coating apparatus 100 has the characteristic of being able to apply acceleration alternately upward and downward to workpiece 30 via suspender 26 by vibrating transport jig 27 in the vertical direction. Here, shake-off drive unit 24 is not necessarily required, and lift drive unit 23 may have the function of vibrating transport jig 27 vertically at short intervals in addition to lowering and lifting transport jig holder 25 toward and from fluidized bed 10. This makes it possible, during fluidized bed dip coating, to shake off any powder paint 13 that has accumulated in excess of the workpiece 30 after the workpiece 30 is lifted from the powder paint 13 in fluidized bed 10.

[0046] Furthermore, the method for manufacturing an insulating coated wiring member in the first embodiment using the fluidized bed dip coating apparatus 100 includes step S107 in which, after lifting the conductor 30A out of the powder coating material 13 in the fluidized bed tank 10, the conductor 30A is vibrated in the vertical direction to shake off any excess powder coating material 13. This prevents the molten coating material from dripping and the cured coating material from blocking the insulating coating mounting hole 35A during the heat treatment for hardening in step S109.

[0047] In other words, after conductor 30A is lifted from powder paint 13 in fluidization tank 10, transport jig 27 is vibrated in the vertical direction, and acceleration is applied alternately upward and downward to conductor 30A via suspender 26. This shakes off any powder paint 13 that has accumulated more than necessary, thereby preventing molten paint from dripping during heat treatment for curing and preventing the cured paint from clogging insulating coating mounting hole 35A.

[0048] Embodiment 2 Next, a method for manufacturing a wiring member having an insulating coating according to the second embodiment will be described with reference to a flow chart S200 shown in Fig. 13. In the second embodiment, only the differences in the configuration from the first embodiment will be described.

[0049] The method for manufacturing a wiring member having an insulating coating in the second embodiment differs from that in the first embodiment only in that step S206 in flow chart S200 is used instead of step S106 in flow chart S100 in the first embodiment. Also in the second embodiment, the fluidized bed dip coating apparatus 100 is used as in the first embodiment.

[0050] In addition, in the first embodiment, it has been explained that the fluidized bed dip coating apparatus 100 can vibrate the transport jig 27 vertically at short intervals when the transport jig 27 is lowered to a height where the workpiece 30 does not come into contact with the powder paint 13. In the second embodiment, the fluidized bed dip coating apparatus 100 has a further feature that the transport jig 27 can vibrate vertically at short intervals even when the workpiece 30 is immersed in the fluidized bed 10.

[0051] 13 shows a flowchart S200 illustrating a method for manufacturing a wiring member having an insulating coating according to embodiment 2. Note that steps S201 to S205 and S207 to S210 in flowchart S200 are similar to steps S101 to S105 and S107 to S110 in flowchart S100 according to embodiment 1, and therefore detailed description thereof will be omitted.

[0052] Fig. 14 shows the manufacturing process of wiring member 32A in step S206 of flowchart S200. Other major manufacturing steps are shown in Figs. 5 to 8 and 10. In step S206, conductor 30A, which has been preheated in step S204, is lowered to a height where it is fully immersed in powder paint 13 flowing in fluidization tank 10.

[0053] Then, with the conductor 30A immersed in the fluidization tank 10, the shake-off drive unit 24 is driven to vibrate the conveying jig 27 in the vertical direction, and the conductor 30A is vibrated in the vertical direction within the powder paint 13 in the fluidization tank 10 via the hanging device 26.

[0054] In addition, in step S206, the shake-off drive unit 24 provided on the support housing 21 of the transport unit 20 of the fluidized bed dip coating apparatus 100 is driven to vibrate the conductor 30A in the up-and-down direction. However, this is not limiting, and for example, the conductor 30A may be vibrated in the up-and-down direction using the lift drive unit 23 that raises and lowers the transport jig 27. Here, the up-and-down direction refers to the upward direction, which is the direction in which the transport jig 27 is raised upward from the fluidized bed 10, and the downward direction, which is the direction in which the transport jig 27 is lowered into the fluidized bed 10.

[0055] After step S206, the process proceeds along steps S207 to S210, which are similar to steps S107 to S110 in the flowchart S100 of the first embodiment, to manufacture the wiring member 32A having the insulating coating 31A.

[0056] Next, the effects of the manufacturing method of a wiring member having an insulating coating in embodiment 2 will be described using Figure 15. Figure 15 shows a cross-sectional view of the conductor 30A shown in Figure 6 taken along the line XX immediately before being placed in a heat treatment furnace in step S209 of flow chart S200. As shown in Figure 15, powder coating material 13 softened or melted by the preheated conductor 30A adheres to the surface of the conductor 30A, forming a coating film 40C. In addition, the thickness of the coating film 40C adhering to the lower surface 38A of the conductor 30A is prevented from becoming thinner than the thickness of the coating film 40C on the upper surface 37A and side surface 39A of the conductor 30A.

[0057] The powder coating material 13 adhering to the lower surface 38A of the conductor 30A is more susceptible to the influence of gravity and is more likely to fall than the upper surface 37A and side surfaces 39A of the conductor 30A. Therefore, in step S206, by vibrating the conductor 30A vertically within the powder coating material 13, the powder coating material 13 is actively pressed against the lower surface 38A of the conductor 30A, increasing the amount of powder coating material 13 adhering to the lower surface 38A of the conductor 30A and making the thickness of the coating film 40C on the lower surface 38A thicker than in the first embodiment.

[0058] 14, the fluidized bed dip coating apparatus 100 in the second embodiment can vibrate the transport jig 27 vertically at short intervals while the workpiece 30 is immersed in the fluidized bed 10. This actively presses the underside of the workpiece 30 against the powder paint 13, thereby increasing the amount of powder paint 13 that adheres to the underside of the workpiece 30.

[0059] Furthermore, by using flowchart S200, which is the method for manufacturing a wiring member having an insulating coating according to the second embodiment, in addition to the effects of the method for manufacturing a wiring member having an insulating coating according to the first embodiment, it is possible to increase the amount of powder coating 13 that adheres to the lower surface 38A of the conductor 30A, and to prevent the thickness of the coating film 40C on the lower surface 38A from being thinner than the thickness of the upper surface 37A and side surface 39A of the conductor 30A, thereby reducing the variation in the thickness of the insulating coating 31A on the wiring member 32A. [Explanation of symbols]

[0060] 10 fluidization tank, 11 hole, 12 perforated plate, 13 powder paint, 14 gas, 20 conveying unit, 21 support housing, 22 support, 23 lifting drive unit, 24 shake-off drive unit, 25 conveying jig holding unit, 26 lifting tool, 27 conveying jig, 30 object to be coated, 30A conductor, 31A insulating coating, 32A wiring member, 33A terminal portion, 34A terminal portion mounting hole, 35A insulating coating portion mounting hole, 36 masking member, 37A upper surface, 38A lower surface, 39A side, 40, 40A, 40B, 40C coating film, 100 fluidization dip coating device, S100, S200 flowchart.

Claims

1. a support housing including a transport jig holder; a fluidization tank for fluidizing the powder coating material; a conveying jig that is held by the conveying jig holding section and that suspends the object to be coated above the fluidization tank; an elevation drive unit provided in the support housing, which lowers the transport jig until the object to be coated is immersed in the fluidization bath and then lifts the object to be coated out of the fluidization bath; A fluidized bed coating apparatus comprising: a first drive unit which is a shake-off drive unit provided in the lifting and lowering portion of the lifting and lowering drive unit, which is raised and lowered together with the conveying jig and the object to be coated by the lifting and lowering drive unit, and which vibrates the conveying jig in the vertical direction.

2. The fluidized bed dip coating apparatus according to claim 1 , wherein the object to be coated is suspended from the transport jig via a suspension tool.

3. The shake-off drive unit is disposed at a position closer to the flow tank than the lifting drive unit, The fluidized bed dip coating apparatus according to claim 1 or 2, wherein the transport jig holding unit is disposed closer to the fluidized bed than the shake-off drive unit.

4. (a) heating an electrical conductor at a first temperature; (b) after the step (a), a step of lowering the conductor from above the fluidization tank in which the powder paint is fluidized by a lifting drive unit to immerse the conductor in the powder paint, thereby adhering the powder paint to the conductor; (c) after the step (b), lifting the conductor from the powder paint by the lifting drive unit and applying acceleration to the conductor alternately in an upward and downward direction, The application of acceleration to the conductor in step (c) is performed by a shaking-off drive unit that is provided on the lifting and lowering part of the lifting drive unit, which raises and lowers the object to be coated together with the transport jig that suspends the object to be coated, and vibrates the transport jig in the vertical direction.

5. 5. The method for manufacturing a wiring member having an insulating coating according to claim 4, further comprising: (d) a step of heating the conductor to which the powder coating is applied at a second temperature after the step (c).

6. 6. A method for manufacturing a wiring member having an insulating coating as described in claim 4 or 5, wherein in step (c), acceleration is applied to the conductor alternately in the upward and downward directions at a height within the fluidization tank where the conductor does not come into contact with the powder paint flowing within the fluidization tank.

7. 7. A method for manufacturing a wiring member having an insulating coating according to claim 4, wherein in step (b), the conductor is vibrated in an up-and-down direction while immersed in the powder coating material.

8. The shake-off drive unit vibrates the conveying jig in the up-and-down direction at a position closer to the flow tank than the position of the lifting drive unit, The method for manufacturing a wiring member having an insulating coating according to any one of claims 4 to 7, wherein the transport jig holding unit holds the transport jig at a position closer to the flow tank than the shake-off drive unit.

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