JPH065128A - Insulated stranded wire, lead wire, and method of manufacturing insulated stranded wire - Google Patents

Abstract

(57) [Summary] [Purpose] To obtain an insulated stranded wire for producing a lead wire without untwisting. [Structure] A twisted portion 7 in which a plurality of insulating element wires 2 each having an insulating film formed on the surface of a conductor are twisted and a non-twisted portion 9 in which the above-mentioned insulating element wires 2 are not twisted are alternately connected, and Both ends of each twisted portion 2 are fixed to each other with an adhesive to form the insulated stranded wire 1. [Effect] Because both ends of each twisted part are fixed,
By simply cutting the center of the non-twisted portion, it is possible to manufacture a lead wire without untwisting. It is also possible to automate the production of insulated stranded wire.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an extra fine insulated stranded wire used for a lead wire connecting a magnetic head and a circuit board used in a disk drive of a computer.

[0002]

2. Description of the Related Art An example of an extremely fine insulated stranded wire used for a lead wire of a conventional disk drive is shown in FIGS. In these figures, reference numeral 1 is an insulated stranded wire. As shown in FIG. 2, the insulated stranded wire 1 is formed by twisting a plurality of insulating wires 2. In general, an insulated stranded wire in which about 2 to 4 insulating strands are twisted together and cut into about 10 cm is often used as a lead wire of a disk drive. Here, an example is shown in which three insulated wires 2 ... Are twisted together.

As shown in FIG. 4, the above-mentioned insulated wires 2 are O
0.5 to 3 on the core conductor 3 made of FC, alloy copper, etc.
An insulating film 6 made of polyurethane or the like is formed on a conductor 5 formed with a gold plating layer 4 having a thickness of about μm.

When this type of insulated stranded wire 1 is used as a lead wire of a disk drive as described above, one end of the insulated stranded wire 1 is attached to the head side by ultrasonic bonding or the like.
The other end is connected to the circuit side by soldering or ultrasonic bonding. Prior to this connection, the insulating stranded wire 1 is processed so that the insulating film 6 at one end or both ends of the terminal is removed and the conductor 5 is exposed.

[0005]

However, the twisted portion 7 of the insulated stranded wire is untwisted during the above-mentioned processing such as the removal of the insulating film, and the straight portion 8 (the untwisted portion) of the terminal becomes long, There is a problem that the workability of bonding to the head is deteriorated. In particular, since the linear portion 8 connected to the small magnetic head is required to be several mm or less,
The incidence of defective products is high. Therefore, at present, the above-mentioned insulated stranded wire for use in the lead wire is manufactured one by one by repeatedly twisting and cutting a single wire by about 15 cm, which hinders automation of the twisting process.

The present invention has been made in view of the above circumstances, and provides an insulated twisted wire and a lead wire which do not untwist, and a method for manufacturing them.

[0007]

In the insulated stranded wire of the present invention, a twisted portion in which a plurality of insulating strands each having an insulating film formed on the surface of a conductor are twisted together, and the insulating strands are not twisted together. The means for solving the above-mentioned problems is that the twisted portions are alternately arranged and both ends of each twisted portion are fixed with an adhesive.

Further, in the method for producing an insulated stranded wire of the present invention, a plurality of insulating element wires each having an insulating film formed on the surface of a conductor are twisted together to form a twisted portion, and an end portion of the twisted portion is bonded with an adhesive. Fixing was used as a means for solving the above problems.

[0009]

The present invention will be described in detail below. 1 and 2 schematically show an embodiment of the insulated stranded wire of the present invention. In these figures, the same parts as those in the conventional example are designated by the same reference numerals to simplify the description.

In these figures, reference numeral 1 is an insulated stranded wire. In addition, each of the three curves indicated by reference numeral 2 represents one insulating wire. As described above, the insulated stranded wire 1 of this embodiment has the twisted portion 7 in which the insulating wires 2 are twisted together and the non-twisted portion 9 in a state in which they are not twisted, and these are alternately arranged. ing.

As the above-mentioned insulated wires 2, ... In the same manner as the insulated stranded wire of the conventional example, the gold plating layer 4 is formed on the core conductor 3 by a conventional method.
And an insulating film 6 is formed on the surface thereof by a conventional method, and the diameter is about 20 to 100 μm. The core conductor 3 has a diameter of 20 to 50 μm.
Some OFC, alloy copper, etc. are used. The thickness of the gold plating layer 4 is preferably about 0.5 to 3 μm. As the insulating film 6, polyurethane, polyester, polyester imide, polyamide imide, polyimide, polyhydantoin, polyvinyl butyral, phenoxy, epoxy or the like is used, and its thickness is preferably about 1 to 50 μm.

The length of the non-twisted portion 9 is twice the length allowed as the straight portion 8 of the end of the lead wire. The total length of the twisted portion 7 and the non-twisted portion 9 is set to match the desired length of the lead wire. The degree of twist of the twisted portion 7 is not particularly limited.

The boundary between the twisted portion 7 and the non-twisted portion 9 is
Fixing points 10 where the insulating wires 2 are fixed by an adhesive.
Are formed. As the adhesive used here,
It is preferable that the curing speed is extremely fast, and specifically, an instant adhesive such as a cyanoacrylate adhesive is used. The degree of fixing with the adhesive may be such that the twisted portion 7 does not untwist during ordinary film treatment and connection.

If such an insulated stranded wire 1 is cut at the center of the non-twisted portion 9 (indicated by an arrow in FIG. 1), a single lead wire is obtained. That is, this lead wire is composed of a twisted portion 7 formed by twisting a plurality of insulating element wires each having an insulating film formed on the surface of a conductor, and a straight portion where the insulating element wires at both ends of the twisted portion 7 are not twisted. And the both ends of the twisted portion are fixed with an adhesive. In such a lead wire, since both ends of the twisted portion are fixed, twisting back does not occur during the film removal processing of the terminal when connecting to the head or the circuit.

Next, an example of the method for producing the insulated stranded wire of the present invention will be described with reference to FIG. First, a long insulating element wire 2 ... Which is a material for the insulated stranded wire is prepared. The number of the insulating strands 2 is not particularly limited and any number can be used, but as described above, it is usually 2 to 4. In this embodiment, the number of insulating wires is three.

Then, these insulating element wires 2 are twisted by using an ordinary automatic twisting machine. This automatic twisting machine is equipped with a dispenser that discharges a fixed amount of adhesive such as instant adhesive.

Here, before the twisting step, the above-mentioned insulated wire 2
.. are aligned from the end, an appropriate point near the end is selected, the adhesive is dropped from the dispenser, and the adhesive is dried to obtain the fixing point A (FIG. 2 (a)).

Next, from the fixing point A, the insulating wire 2
The strands are twisted together, and when the twisted portion 7 reaches a predetermined length, an adhesive is dropped from the dispenser onto the end of the twisted portion 7, and the insulating wires 2 at the ends of the twisted portion 7 are mutually connected. And the twist is fixed to form a fixing point B. Fixing with this adhesive takes only a few seconds.

Next, while the twisting of the automatic twisting machine is stopped, each of the insulated wires 2 ... Is unwound by a predetermined length and the non-twisted portion 9 is formed. Then, when the twisting is started again, the adhesive is dropped from the dispenser to form the fixing point A ′ (FIG. 2 (b)).

Further, the fixed point A is replaced by the fixed point A ',
By performing the above-mentioned twisting step and fixing step and repeating the same operation thereafter, a long insulated stranded wire 1 in which twisted portions 7 and non-twisted portions 9 are alternately connected as shown in FIG. 1 is manufactured. Thus, according to the method for producing an insulated stranded wire of the present invention,
An insulated stranded wire can be automatically and efficiently manufactured by using a slightly modified normal automatic stranded wire machine.

[0021]

As described above, in the insulated stranded wire of the present invention, the twisted portion in which a plurality of insulating strands each having an insulating coating formed on the surface of the conductor are twisted together with the insulating strand are not twisted. The twisted portions are alternately arranged, and both ends of each twisted portion are fixed with an adhesive. Therefore, since both end portions of each twisted portion are fixed, a lead wire without untwisting can be manufactured only by cutting the center of the non-twisted portion.

The lead wire of the present invention is one in which both ends of a twisted portion formed by twisting a plurality of insulating element wires each having an insulating coating formed on the surface of a conductor are fixed with an adhesive. Therefore, since both end portions of the twisted portion are fixed, there is no twist back during the film removal treatment of the terminal before connecting to the head or circuit.

Further, according to the method for producing an insulated stranded wire of the present invention, a plurality of insulating element wires having an insulating film formed on the surface of a conductor are twisted together to form a stranded portion, and an end of the stranded portion is bonded with an adhesive. It sticks. Therefore, workability is improved and a long insulated stranded wire can be manufactured. It is also possible to automate the production of insulated stranded wire.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing an example of an insulated stranded wire of the present invention.

FIG. 2 is a schematic side view showing an embodiment of the method for producing an insulated stranded wire of the present invention.

FIG. 3 is a side view showing an example of an insulated stranded wire according to the present invention.

FIG. 4 is a cross-sectional view showing an example of a conventional insulated stranded wire.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Insulated stranded wire, 2 ... Insulating strand, 5 ... Conductor part, 6 ... Insulating film, 7 ... Twisted part 9 ... Untwisted part

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Toshio Niwa 1-5-1, Kiba, Koto-ku, Tokyo Within the Fujikura Electric Wire Co., Ltd. (72) Inventor Toshio Onuma 1440, Rosaki, Sakura City, Chiba Fujikura Electric Cable Co., Ltd. Sakura Inside the factory (72) Inventor Kazuo Tanihira 1440 Rokuzaki, Sakura-shi, Chiba Fujikura Electric Cable Co., Ltd.Sakura factory (72) Inventor Norio Mori 1440 Rokuzaki, Sakura-shi, Chiba Fujikura Electric Co., Ltd.Sakura factory

Claims (3)

[Claims] 1. A twisted portion formed by twisting a plurality of insulating wires formed with an insulating film on the surface of a conductor and a non-twisted portion in which the insulating wires are not twisted are alternately connected to each other, and An insulated stranded wire in which both ends of each twisted part are fixed with an adhesive. 2. A lead wire in which both ends of a twisted portion formed by twisting a plurality of insulating element wires each having an insulating film formed on the surface of a conductor are fixed with an adhesive. 3. A plurality of insulating wires each having an insulating coating formed on the surface of a conductor are twisted together to form a twisted portion, and
A method for manufacturing an insulated stranded wire, wherein an end of a twisted portion is fixed with an adhesive.