JPH05227629A - Method for finishing end of insulated cable - Google Patents

Abstract

PURPOSE:To provide a method of finishing the end of an insulated cable, which has the insulating resin coating consisting of applied and burned resin, wherein the heat resistance life by the stipulation IEC Public 172 is 180 deg. ore more, by carbonic acid gas laser. CONSTITUTION:This is a method for finishing the end of an insulated cable, which executes the second process at least two times repeatedly, having a first process of applying carbonic acid gas laser beam to the terminal of an insulated cable, which has the above-mentioned insulating resin coating, so as to remove the insulator coating from the end part, and a second process of soaking the end part, where the insulator coating is removed, in flux, and next, performing soldering.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a method of terminating an electrically insulated wire having an electrically insulated conductor layer formed by coating and baking a resin having a heat-resistant life of 180 ° C. or higher according to IEC Public 172. For example, the present invention relates to a method of peeling the electric insulating layer from the terminal and performing a necessary treatment in order to connect the electric insulated wire having the electric insulating layer to the terminal.

[0002]

2. Description of the Related Art When connecting an electrically insulated wire to a terminal, it is necessary to remove the electrically insulating resin film on the terminal portion of the electrically insulated wire by some method. Generally, there are a chemical peeling method using a chemical such as acid and alkali, a peeling method by heating, and a mechanical peeling method. However, when the conventional method for peeling off an electrically insulating resin film as described above is applied to a recent electrically insulated electric wire that has been heat-resistant and has been reduced in diameter at the same time, the treatment is reliable because of the following reasons. It lacks sex. That is, there is a problem that the conductor itself is melted when the method of peeling the insulating resin film by heating is applied to the heat-resistant small-diameter electrically insulated wire, and the conductor is remarkably damaged by the application of the mechanical peeling method, resulting in disconnection or the like. The chemical peeling method using a chemical has a problem that the chemical diffuses and permeates into the peeled portion and the coating or conductor around the peeled portion, and chemically corrodes the conductor and the coating at the terminal portion.

[0003]

In view of the above circumstances, the inventors of the present invention have proposed a method for removing a terminal film of an electrically insulated electric wire using a laser and an electrically insulated electric wire suitable for the method. For example, the present inventors proposed in Japanese Patent Application No. 2-215472 an electrically insulated electric wire suitable for peeling a terminal film by using a carbon dioxide gas laser.
No. 5473 has proposed an electrically insulated wire suitable for exfoliating a terminal film using an excimer laser. More recently, it has been demanded that the method of peeling the terminal coating by irradiating a gas laser beam be widely applied to a more general heat-resistant small-diameter electrically insulated wire. But, for example, IEC
A carbon dioxide gas laser is applied to an electric insulated wire having an electric insulating resin film formed by coating and baking a resin having a heat resistance life of 180 ° C or more as defined by Public 172, for example, a polyimide electric wire, a polyamide-imide electric wire, a polyamide-imide overcoated polyester-imide electric wire, or the like. It has been extremely difficult to peel off the electrically insulating resin film by applying the method according to the above method because of the heat resistance of the film. For this reason, the object of the present invention is to end-process an electrically insulated wire having an electrically insulating resin film formed by coating and baking a resin having a heat resistant life of 180 ° C. or more according to the above-mentioned IEC Public 172 with a carbon dioxide laser. It is to provide a method.

[0004]

The above object can be achieved by a method of terminating an electrically insulated wire having the following features according to the present invention. That is, (1) a step of irradiating the terminal portion of the above-described electrically insulated wire with carbon dioxide laser light to peel off the electrical insulator coating from the terminal portion, and (2) fluxing the terminal portion from which the electrical insulator coating is peeled off. The method for terminal treatment of an electrically insulated electric wire is characterized in that the step (2) is repeated at least twice.

The carbon dioxide gas laser used in the present invention is preferably a pulse oscillation type carbon dioxide gas laser having an output of 4 to 6 J.
As the flux used in the present invention, JISZ328
Although any of A-class, B-class, AA-class, etc. defined in 3 can be used, according to experiments by the present inventors, the B-class flux has the greatest soldering effect. Flux immersion,
Next, the required number of repetitions of the solder dipping process depends on the type of electrically insulating resin film of the electrically insulated wire, the film thickness, the material of the conductor,
Although it depends on the wire diameter, a good soldering process can usually be performed by repeating at least twice. Suitable processing conditions are
The flux immersion time is in the range of 0.5 seconds to 1 second, the solder immersion temperature is in the range of 300 ° C to 400 ° C, and the solder immersion time is in the range of 1 second to 3 seconds. Flux dipping and solder dipping are carried out by conventional methods.

The principle of the method of terminating an electrically insulated wire according to the present invention is roughly interpreted as follows. That is, even after irradiation with carbon dioxide laser light, there is a very thin electrically insulating resin film on the conductor surface, the first flux immersion,
Then, in the step of dipping the solder, the solder only partially penetrates between the conductor and the electrically insulating resin film. Therefore, at this stage, the soldering process is performed only in a very small portion. However, when viewed microscopically, many cracks due to heat are generated on the surface of the remaining electrically insulating resin film, and during the second flux dipping process and then the solder dipping process, the solder cracks in the electrically insulating resin film. It can be construed that the soldering process is completed by entering from the direction toward the conductor. By the terminal treatment method of the electric insulated wire according to the present invention, the electric insulating resin film of the polyimide electric wire, the polyamideimide electric wire, the polyamideimide overcoat polyesterimide electric wire and the like, which were not possible by the conventional method, can be peeled very easily, Moreover, the soldering process can be performed. Hereinafter, the present invention will be described in more detail based on Examples and Comparative Examples.

[0007]

Example 1 A copper wire having a diameter of 0.1 mm was coated with a polyimide resin coating (trade name Pyr-ML manufactured by DuPont, USA) and baked to give a thickness of 1
A polyimide electric wire having a 0 μm polyimide resin film was prepared as a sample. Using a pulsed carbon dioxide laser (produced by Ushio Denki Co., Ltd., output: 6J), this electrical insulated wire was tested from two radial directions different from each other by 180 ° in the sample (indicated as front and back in Table 1). The sample was irradiated with a carbon dioxide laser beam at a rate of 3 pulses / sec for each 40 pulses. The sample of the electrically insulated electric wire after irradiation with the carbon dioxide gas laser light was dipped in a class B flux (Ishikawa Metal Co., Ltd., trade name 115B) for 1 second, and further dipped in a solder bath at a solder bath temperature of 350 ° C for 2 seconds. .. Subsequently, under the same conditions, similarly, the second flux dipping and then the solder dipping were performed to end-treat the sample of the electrically insulated electric wire to obtain Example product 1 of the terminal portion of the electrically insulated electric wire. Table 1 summarizes the conditions of the terminal treatment method such as the types of resin paints described above and the irradiation conditions of carbon dioxide laser light.
Described in. As a result of observing the example product 1, as described in the column of the soldering state of the terminal in Table 1, the soldering treatment was successfully completed. Here, the evaluation of good is that the terminal treatment is of course complete on the surface, and further, when the cross section of the terminal is observed, the interface between the conductor and the solder is completely joined, and the electrically insulating resin film is formed on the terminal. Means that there was no remaining.

[0008]

[Table 1]

Examples 2 to 5 Electrically insulated wire samples to which Examples Methods 2 to 5 were applied were prepared as follows. The polyamide-imide wire to which the methods 2 and 5 of Examples are applied was obtained by applying a product name H1406 manufactured by Hitachi Chemical Co., Ltd. as a polyamide-imide resin coating, and coating and baking it on a copper wire having a diameter of 0.1 mm. Film thickness 10
An electrically insulated wire of μ was used. For a polyamide-imide overcoated polyester electric wire to which the method 3 of the embodiment is applied, a copper wire having a diameter of 0.1 mm is coated with 8 μm of polyester-imide resin coating (product name: Isomid manufactured by Nippon Schenectady).
An electrically insulated electric wire was used which was applied and baked to a thickness, and a polyamideimide resin coating (H1406 manufactured by Hitachi Chemical Co., Ltd.) was applied and baked thereon to a thickness of 2 μm. The polyimide wire of Example Method 4 was the same as the electrically insulated wire sample to which Example Method 1 was applied. Then, in the same manner as in Example 1 under the conditions of the number of laser irradiations, the type of flux, the solder temperature, the immersion time in the solder bath, and the number of repeated cycles shown in Table 1, each terminal treatment method of the electrically insulated wire according to the present invention was performed. It carried out to the electric insulated wire sample, and obtained the example goods 2-5.
The obtained example products 2 to 5 were observed in the same manner as in the example product 1. The results were good as shown in Table 1.

Comparative Examples 1-5 Examples 1-5, except that as shown in Table 1, the steps of flux immersion and then solder immersion were performed only once.
Laser irradiation, flux dipping, and solder dipping were performed on the electrically insulated electric wire samples respectively manufactured in the same manner as in Examples 1 to 5 under the same conditions as those of Comparative Example Products 1 to 1 at the end of the electrically insulated electric wire sample. Got 5. The obtained comparative example products 1 to 5 were observed in the same manner as in the example product 1, and the results are shown in Table 1. In the case of the comparative example method in which the steps of flux dipping and then solder dipping were carried out only once, as shown in Table 1, the soldering state of the terminal was poor. Here, the evaluation of being defective means that, when the cross section of the terminal portion is observed, the joining of the interface between the conductor and the solder is incomplete, and the electrically insulating resin film partially remains on the terminal portion. ..

[0011]

INDUSTRIAL APPLICABILITY According to the present invention, it is said that it is difficult to apply the conventional method of peeling the electrically insulating resin film by the carbon dioxide laser by repeating the steps of flux immersion and then solder immersion at least twice after the carbon dioxide laser irradiation. IE was
It is also possible to remove the coating by carbon dioxide gas laser on an electrically insulated wire that has an electrically insulating resin coating layer formed by coating and baking a resin with a heat resistance life of 180 ° C or more as defined by C Public 172. This improves the reliability and work efficiency of the terminal treatment of the heat-resistant and small-diameter electrically insulated electric wire, and further has the effect of increasing the reliability of the electric equipment using the heat-resistant and small-diameter electrically insulated electric wire. ..

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Yoshitaka Tokimori 1-1, Showa-cho, Kariya city, Aichi Prefecture Nihon Denso Co., Ltd. (72) Inventor Yoshitaka Natsume 1-1-1-1, Showa town, Kariya city, Aichi prefecture Sozo Co., Ltd.

Claims (1)

[Claims] 1. A method of terminating an electrically insulated electric wire having an electrically insulating electric conductor layer, which is formed by coating and baking a resin having a heat resistance life of 180 ° C. or more according to IEC Public 172, (1) The electrically insulated electric wire A step of irradiating the terminal part of the carbon dioxide gas laser beam to peel off the electric insulator film from the terminal part, and (2) immersing the terminal part from which the electric insulator film is peeled in flux, and then soldering And a step of performing the step (2) repeatedly at least twice.