JPH05151831A - Flat cable - Google Patents

Abstract

PURPOSE:To provide a flat cable which has good workability and also is easy to perform its terminal processing work. CONSTITUTION:A flat cable 1 used as an under-carpet cable has substantially a same shape as the prior art and has its shape made in a flat form by providing a sheath 3 of a cross-section shaped in substantially trapezoid form on the circumference of a cable core 2. To be concrete, the cable core 2 is disposed in the central part and ear parts 6, 6 each having a slope are provided on both sides thereof and V-shaped separation grooves 4, 4, ..., 4 extending in the direction of the length of the flat cable 1 are provided between the sheath on the circumference of the cable core 2 and the ear parts 6, 6. In addition, air gaps 5, 5 are formed as shown in the drawing on both contact parts in the horizontal direction with respect to the circumferential surface of the cable core 2 and the sheath 3.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement of a flat cable suitable for use as an undercarpet cable laid on a floor surface.

[0002]

2. Description of the Related Art Generally, a flat cable 10 used as an under carpet cable of this type has a flat outer shape by providing a sheath 30 having a substantially trapezoidal cross section on the outer periphery of a cable core 2 as shown in FIG. In particular,
The cable core 2 is arranged in the central portion, and the ear portions 6 and 6 having inclined surfaces are provided on both sides of the cable core 2. The flat cable 10 extends in the longitudinal direction between the outer peripheral sheath of the cable core 2 and the ear portions 6 and 6. , V-shaped separation grooves 4, 4, ..., 4 are provided.

When the flat cable 10 is actually wired on the floor surface, in order to connect the connector to its own terminal portion, as shown in FIG. 10, the separation grooves 4 and 4 are provided along the longitudinal direction. After making a cut with a cutter blade (not shown) for a predetermined length to separate the ears 6 and 6 from the outer sheath of the cable core 2 and cutting these separated ears 6 and 6, As shown, use the special stripper 15 to peel off the outer sheath of the cable core 2,
As shown in FIG. 12, it is necessary to expose the cable core 2 for a predetermined length.

[0004]

However, according to the above-mentioned conventional example, when the ends 6 and 6 are separated from the sheath on the outer periphery of the cable core 2 when the terminal processing is performed as described above,
If the cutter blade does not make a cut in the separation grooves 4 and 4 without meandering along the longitudinal direction, the outer diameters of the cable cores 2 separated from the ears 4 and 4 will have uneven sheath diameters. When the sheath on the outer periphery of the cable core 2 is peeled off by using the dedicated stripper 15, the sheath cannot be peeled off, or the blade of the stripper 15 is cut off.
Since there is a risk of damaging the signal line inside the machine, there is a significant inconvenience that the working process requires skill and the workability is poor, and a special tool such as the stripper 15 is required.

[0005]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a flat cable which improves the disadvantages of the above-mentioned conventional examples, has good workability, and can easily perform a terminal processing operation.

[0006]

Therefore, in the present invention, in a flat cable in which at least one core wire is covered with a sheath having a trapezoidal cross section, the sheath is vertically extended in the width direction of the flat cable. It is intended to achieve the above-mentioned object by adopting a configuration in which it is divided into two along the line.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT An embodiment according to the present invention will be described below with reference to FIGS.
It will be explained based on.

Here, the same components as those in the conventional example are designated by the same reference numerals.

The flat cable 1 used as the undercarpet cable shown in FIG. 1 has a shape similar to that of the conventional example described above, and a sheath 3 having a substantially trapezoidal cross section is provided on the outer periphery of the cable core 2 to form an outer shape. Is a flat shape. Specifically, the cable core 2 is arranged in the central portion, and ear portions 6 and 6 having inclined surfaces are provided on both sides of the cable core 2. The sheath and the ear portions 6 and 6 on the outer periphery of the cable core 2 are provided. , And V-shaped separating grooves 4, 4, ..., 4 extending in the longitudinal direction of the flat cable 1.
Is provided. Then, voids 5 and 5 are formed at both horizontal contact portions between the outer peripheral surface of the cable core 2 and the sheath 3, as shown in the drawing.

Specifically, the voids 5 and 5 are continuously provided along the longitudinal direction of the flat cable 1, whereby the sheath 3 is formed into the voids 5 and 5 as shown in FIG. The upper sheath 13 and the lower sheath 23 are configured with the section as a boundary.

In the terminal processing operation of this flat cable 1, the sheath 3 is torn up and down the voids 5 and 5 with fingertips or the like,
The unnecessary sheaths 13 and 23 that have been torn are cut off with the scissors 14 to expose the cable core 2 for a predetermined length.

As will be described later, the gaps 5 and 5 are formed in the sheath 3 in order to horizontally divide the sheath 3 into two parts in the step of extruding and covering the outer periphery of the cable core 2 with the sheath 3. The gaps 5 and 5 are not necessarily formed because they are formed in order to form a weakly fused portion. That is, it suffices if a portion where the fusion of the sheath is weak can be formed so that the sheath 3 can be divided into upper and lower parts with respect to the horizontal plane.

A method of manufacturing the flat cable 1 will be described with reference to FIGS. 4 to 8.

In FIG. 4, 22 is a die, and 24 is a die.
Indicates a nipple arranged inside the die. As shown in the drawing, the die 22 is provided with a hole 20 having a shape substantially the same as the cross-sectional shape of the flat cable 1. Further, a through hole 26 through which the cable core 2 penetrates is provided at the tip of the nipple 24.

Then, the nipple 24 is inserted inside the die 22 so that the tip of the nipple 24 is spaced apart from the inner surface of the die 22 by a predetermined distance D [mm]. in this case,
The distance D [mm] is set to be 1/2 or less of the thickness E [mm] of the flat cable 1 to be formed.

When the flat cable 1 is manufactured by using the die 22 and the nipple 24 arranged in this way, the sheath 3 is extruded and coated on the outside of the cable core 2 which moves from the through hole 26 of the nipple 24 to the die 24 side. If you do
Since the distance D between the hole 20 of the die 22 and the tip of the nipple 24 is short, the discharge pressure applied when the coating material resin flowing along the surface of the nipple 24 goes out from the hole 20 of the die 22 becomes weak. (See FIGS. 6 and 7). That is, FIG.
As shown in (a), if the normal distance D is sufficiently long, the covering material resin coming from the vertical direction of the nipple 24 is sufficiently filled at the tip of the nipple, so that the covering material resin near the outer peripheral surface of the cable core 2 is fused. Will be good. However,
Thickness E [mm] of the flat cable 1 where the distance D is formed
8 (b) nipple 2
Since the coating material resin coming from the vertical direction of 4 is extruded and coated on the outer periphery of the cable core 2 without being sufficiently filled at the tip of the nipple, the fusion of the coating material resin near the outer peripheral surface of the cable core 2 (fusion bonding) Is weak) is formed. That is, this portion becomes the voids 5 and 5.

[0017]

EFFECTS OF THE INVENTION Since the present invention is constructed as described above, it is possible to provide a flat cable which has good workability and can easily carry out terminal processing work.

[Brief description of drawings]

FIG. 1 is a perspective view of a flat cable according to an embodiment of the present invention.

FIG. 2 is an explanatory view showing a terminal processing step of the flat cable shown in FIG.

FIG. 3 is an explanatory view showing a terminal processing step of the flat cable shown in FIG.

FIG. 4 is an explanatory view showing a method for manufacturing the flat cable shown in FIG.

5 is an explanatory view showing a method for manufacturing the flat cable shown in FIG.

FIG. 6 is an explanatory view showing the flow of coating material resin on the surface of the nipple.

FIG. 7 is an explanatory diagram of an extrusion coating step.

FIG. 8 is an explanatory diagram of an extrusion coating step.

FIG. 9 is a perspective view of a flat cable according to a conventional example.

10 is an explanatory diagram showing a terminal processing step of the flat cable shown in FIG.

11 is an explanatory view showing a terminal processing step of the flat cable shown in FIG.

12 is an explanatory view showing a terminal processing step of the flat cable shown in FIG.

[Explanation of symbols]

 1 ... Flat cable 2 ... Cable core 3 ... Sheath 4 ... Groove 5 ... Void

Claims (1)

[Claims] 1. A flat cable in which at least one core wire is covered with a sheath having a trapezoidal cross section, and the sheath is divided into two parts vertically in the width direction of the flat cable along the longitudinal direction. A flat cable characterized by that.