JP3037444B2 - Flat cable - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a flat cable such as a tape wire used for connecting a print head of a printer, and more particularly to a flat cable having excellent flexibility.

[0002]

2. Description of the Related Art FIG. 2 is a sectional view showing a tape wire as an example of a conventional flat cable.

A portion of a flat conductor 1 (rectangular conductor) except for both ends is covered with an insulator 2. Due to manufacturing constraints that it is difficult to stably make the conductor 1 extremely thin in its length direction, the conductor 1 usually has a thickness of about
Those having a thickness of 0.035 to 0.1 mm are used. A reinforcing plate 3 is provided on the exposed portion of the conductor 1 and on the insulator 2 in the vicinity thereof.
Is attached. The reinforcing plate 3 is provided to reinforce the strength at both ends of the conductor 1. Further, the conductor 1 and the reinforcing plate 3 located at both ends of the flat cable are fitted into a predetermined connector, whereby the terminals of the connector and the conductor 1 are electrically connected. The thickness t is set to, for example, about 0.3 mm in both cases.

The flat cable thus constructed has both ends connected to a print head of a printer or the like, and has a central portion which is flexibly bent as required. Further, since the reinforcing plates 3 are provided at both ends of the flat cable, the conductor 1 does not bend and break at both ends.

[0005]

However, in the above-mentioned conventional flat cable, the thickness of the conductor 1 is about 0.035.
Since it is formed at the same thickness over the entire length of 0.1 mm to 0.1 mm, there is a problem that its flexibility is extremely poor.

For example, when a flat cable is used to connect a print head of a printer, both ends of the flat cable are fixed to a device and a print head of the printer. The central portion of the cable repeatedly undergoes a U-shaped bend. However, the conventional flat cable has poor flexibility, so that fatigue disconnection is likely to occur due to repeated bending. Furthermore,
With the recent miniaturization of electronic devices, the bending diameter of the above-mentioned U-shaped bending has become smaller, and the use conditions of flat cables have become increasingly severe. Therefore, there is a demand for development of a long-life flat cable that can increase the speed of an electronic device and improve the reliability of connection.

It is difficult to use the above-mentioned flat cable under severe bending conditions. Therefore, an expensive flexible printed circuit (hereinafter referred to as FPC) having excellent flexibility is used instead of the flat cable. I have to do it.

On the other hand, in order to improve the flexibility of the flat cable by reducing the thickness of the conductor 1 as a whole, the thickness of the reinforcing plate 3 is reduced due to the connection with the connector connected to the flat cable. Since it is necessary to increase the thickness, the reinforcing plate 3 needs to be of a special type different from the conventional type. For this reason, there is a problem that the manufacturing cost of the flat cable is significantly increased.

When the thickness of the conductor 1 is reduced,
The mechanical strength of itself and the adhesive strength with the insulator 2 are significantly reduced, and the proof strength at the connection with the connector is reduced. Then, the flat cable has reduced durability against insertion and removal of the connection with the connector, and cannot be put to practical use.

The present invention has been made in view of the above problems, and has as its object to provide a flat cable having excellent flexibility and low manufacturing cost.

[0011]

The flat cable according to the present invention is used for applications which are repeatedly bent, and in a flat cable in which a flat conductor is covered with an insulator, the bent portion of the flat cable is flattened. And thinner than the connecting portions at both ends.

[0012]

According to the present invention, the conductor is formed so that the thickness of the bent portion is smaller than that of the connecting portions at both ends. For this reason, the flat cable according to the present invention has excellent flexibility at the bent portion. Further, the thickness of the connection portion of the conductor can be the same as the thickness of the conductor of the conventional flat cable. For this reason, the proof stress at the connection portion with the connector does not decrease. Further, when a reinforcing plate or the like is provided on the conductor, and the reinforcing plate and the conductor are fitted into a connector or the like of a predetermined size, the conductor and the terminal of the connector are connected to each other. Thicknesses similar to conventional ones can be used. Therefore, since it is not necessary to use a special reinforcing plate, the manufacturing cost of the flat cable does not increase. Thereby, a flat cable having excellent flexibility at the bent portion can be manufactured at low cost.

According to the present invention, an expensive FPC is used for connecting a print head or the like of a printer having a severe bending condition.
Instead, an inexpensive flat cable can be used.

In the present invention, if the thickness of the bent portion is less than 0.01 mm, the conductor may be broken at the bent portion, and the thickness of the bent portion is 0.05 mm.
If it exceeds, the flexibility becomes insufficient. Therefore, it is preferable that the thickness of the bent portion of the conductor be 0.01 to 0.05 mm.

Further, even if the bent portion is formed thin to obtain flexibility as described above, the conductivity as a flat cable is sufficiently ensured.

[0016]

Next, an embodiment of the present invention will be described with reference to the accompanying drawings.

FIG. 1 is a sectional view showing a tape electric wire according to an embodiment of the present invention.

The flat conductor 1 is flattened at a bent portion 4 (length: L) at the center in the longitudinal direction, and the thickness of the bent portion 4 is smaller than the thickness of both sides. Have been. This conductor 1 usually has a thickness of about
The thickness of the bent portion 4 is, for example, about 0.01 to 0.05 mm. In addition, the thickness and length L of the bent portion 4 are determined appropriately according to the application of the tape wire. The bent portion 4 can be formed by rolling only the central portion of a normal rectangular conductor. However, the method of forming the bent portion 4 is not limited to this, and various methods can be considered.

The plurality of conductors 1 are arranged in parallel on the same plane, and a portion except for both ends of the conductor 1 is an insulator 2.
Coated with A reinforcing plate 3 is attached on the exposed portion of the conductor 1 and on the insulator 2 in the vicinity thereof.

In the tape wire constructed as described above, the conductor 1 has excellent flexibility in the bent portion 4 which is formed relatively thin. In addition, since the thickness of the connection portion at both ends of the conductor 1 is the same as that of the related art, the strength at the connection portion with the connector does not decrease. Further, the reinforcing plate 3 having the same thickness as the conventional one can be used, and there is no need to manufacture a special one.

Therefore, according to the present embodiment, an inexpensive flat cable can be used for connecting a print head portion or the like of a printer whose bending conditions are severe.

[0022]

As described above, according to the present invention, the conductor of the flat cable is flattened at the bent portion so as to be thinner than the connection portion at both ends, so that the flexibility at the bent portion is excellent. I have. Further, the same reinforcing plate as that of the related art can be used as the reinforcing plate provided on the conductor. Therefore, the flat cable according to the present invention has excellent flexibility and low manufacturing cost.

As a result, there is an effect that an inexpensive flat cable can be used instead of an expensive FPC when connecting a print head portion or the like of a printer having severe bending conditions.

[Brief description of the drawings]

FIG. 1 is a sectional view showing a tape electric wire according to an embodiment of the present invention.

FIG. 2 is a sectional view showing a conventional tape electric wire.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1; Conductor 2; Insulator 3; Reinforcement plate 4;

Claims (1)

(57) [Claims] (1) It is used for an application which repeatedly receives bending.
In a flat cable in which a flat conductor is covered with an insulator, a bent portion of the conductor is flattened so as to be thinner than a connection portion at both ends.