JPH0239045B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention comprises forming a cable core by applying an insulator such as rubber or plastic on a conductor, and wrapping a semiconductive tape and a plurality of horizontally wound copper wires on the insulator. This invention relates to an electric cable provided with a shield and a method for manufacturing the same.

In recent years, with the increase in the capacity of electric cables, the cable size has also increased, and as for the flexible structure, instead of copper tape wrapping or copper wire braiding, a flexible structure consisting of a semiconductive layer and horizontally wound copper wire has become practical. has been made into

Its basic structure has a volume resistivity of 10 ³ to 14 ⁴ Ω−
A semi-conductive tape made by frictioning cm of rubber or plastic mixture into a woven or non-woven fabric made of natural or synthetic fibers is wrapped around the cable insulation, and multiple strips of copper wire are wound horizontally around the outside of the tape. The semiconductive tape is usually wound with a pitch that is 1/5 to 1/15 of the pitch of horizontally wound copper wire, but both sides of the semiconductive tape are smooth.

In addition, the process of horizontally winding copper wire onto a cable can be divided into two types: one in which the copper wire is rotated around the cable on the sending side of the cable, and the other in which the copper wire is not rotated but the cable itself is rotated around its axis. The present invention relates to a method of horizontally winding copper wire using a sheathing machine or a twisting machine that rotates the cable itself. When winding semiconducting tape, horizontally winding copper wire, or thinning a cable using a sheathing machine or a twisting machine that rotates the cable itself, conventionally, the insulated wire core is first placed on the rotating insulated wire core. It is manufactured by winding semiconductive tape with a pitch of 20 to 60 mm using a tape winding machine, and then adding copper wire vertically on top of it and wrapping it at the pitch of the insulated wire core as it rotates. In the process, the number of rotations of the tape winding machine that winds the semiconductive tape becomes a condition that determines the limit of the manufacturing speed, that is, a rate-determining condition.

In addition, the diameter of copper wire for shielding is usually about 0.8 to 1.4
It is a copper wire with a circular cross section of mm, and a long pitch (100 ~
500mm), and when multiple such copper wires (usually 5 to 100) are wound on semiconductive tape on an insulated core, the spacing between each copper wire is 1 to 10mm.
It is.

The above conventional manufacturing method requires a tape winding machine to wind the semiconductive tape during the manufacturing process, and the manufacturing speed is limited by the rotational speed capacity of this tape winding machine. When the insulated wire core passes through the inner guide roller or when it is wound onto the winding drum, it shifts in the circumferential direction, and due to the structure of the copper wire product, multiple This method has the disadvantage that the intervals between the strips of copper wire in the circumferential direction are uneven.

The present invention has been made in order to eliminate the above-mentioned conventional drawbacks, and it is an object of the present invention to provide a cable in which the distance between copper wires and copper wires is maintained evenly as a cable structure, and to provide a cable in which the distance between the copper wires is maintained evenly. It provides a means for manufacturing. That is, the present invention is the same as the conventional tape in that the semiconductive tape is made of a woven or nonwoven fabric made of natural or synthetic fibers and a semiconductive rubber or plastic mixture, but it is different from the conventional tape. One side of the semiconductive tape is provided with a row of protrusions arranged in a certain direction and formed intermittently, and is wound on the insulator of the cable with the surface on which the protrusion row is provided facing outward. The present invention provides a copper wire electric cable in which copper wires are arranged at approximately equal intervals one by one and wound horizontally, and at the same time, the above-mentioned semiconductive tape and copper wire are rolled together. The cable is attached vertically to the surface of the cable insulator and wound around the rotating pitch (100 to 500 mm) of the insulated wire core to produce a high-quality flexible cable. The present invention also provides a manufacturing method that improves manufacturing efficiency since it is no longer necessary.

Next, the present invention will be explained with reference to the drawings. 1st
The figure shows an example of the electric cable of the present invention.
An inner semiconductive layer 2, an insulator 3, a semiconductive tape wrap (outer semiconductive layer) 4, a shielding copper wire 5, and a plastic sheath 6 made of polyethylene, polyvinyl chloride, etc. are sequentially provided on the conductor 1. It is something that Second
The figure shows an example of the semiconductive tape used in the electric cable shown in Figure 1, which is made of woven or nonwoven natural or synthetic fibers made of friction rubber or plastic mixture mixed with conductive carbon black to make it conductive. The protrusions 7 are formed on one side intermittently in the length direction by processing with a roll or the like so that they are arranged in several rows at regular intervals (four rows in the figure).
Of course, the shape of this protrusion is not limited to that shown in the drawings and may be arbitrary. Note that the protrusion rows may be formed so that the copper wires are evenly arranged, the number of protrusion rows and copper wires may not be the same, and the intervals between the protrusion rows do not necessarily have to be constant.

To manufacture the electric cable of the present invention, as shown in FIG. During winding, the insulated conductor is first wrapped with a semiconductive tape 4 as shown in FIG. 2 while rotating the insulated conductor itself around its axis simultaneously in the same direction on the sending side and the winding side. While attaching the wire vertically to the surface as shown in FIG. By removing the wire, a cable having an external shield in which a semiconductive tape and a copper wire for shielding are wound horizontally around an insulated wire core is obtained.

After this, a plastic sheath, such as a polyethylene or vinyl chloride sheath, can be applied to obtain the cable of the invention.

The present invention has such a cable structure, and since one copper wire is arranged between the rows of protrusions in the length direction of the semiconductive tape, the copper wire easily collapses during the cable manufacturing process. In addition, the cable is wound around the rotating pitch (100 to 500 mm) of the insulated wire core of the cable, and can be manufactured without the need for a special tape winding machine. In addition,
The semiconductive tape used in the present invention can be used for cables of different sizes.

[Brief explanation of drawings]

Fig. 1 is a cross-sectional view showing an example of the electric cable of the present invention, Fig. 2 is a perspective view showing an example of the semiconductive tape used in the invention, and Fig. 3 is a manufacturing process of the electric cable of the present invention. FIG. DESCRIPTION OF SYMBOLS 1... Conductor, 2... Internal semiconductive layer, 3... Insulator, 4... Semiconductive tape winding, 5... Copper wire for insulation, 6... Plastic sheath, 7... Protrusion.

Claims (1)

[Claims] 1. A semi-conductive tape winding layer is provided on the cable insulator, and the semi-conductive tape has a plurality of rows of protrusions arranged intermittently in a certain direction on the outer surface. An electric cable characterized in that a flexible layer is provided between the rows of protrusions, each of which is made up of a plurality of metal wires arranged and wound individually at approximately equal intervals. 2. The semi-conductive tape is made by frictionally applying semi-conductive rubber or plastic to a woven or non-woven fabric made of natural fibers or synthetic fibers, and a row of protrusions formed intermittently in the longitudinal direction on one side are arranged in parallel. An electric cable according to claim 1. 3 An insulated wire core is advanced while rotating at a constant speed around its axis, and a half-shaped insulated wire core is provided with a row of projections formed intermittently in the length direction on one side of the advancing insulated wire core. An electric cable characterized in that a conductive tape is vertically attached with the smooth side facing inside, and a plurality of conductive wires are individually arranged and vertically attached at approximately equal intervals between the rows of protrusions of the semiconductive tape. Production method.