JPS638031Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to improvements in flat flexible cables. Flat flexible cables used as power supply cables for mobile electrical equipment, such as elevators, have multiple twisted insulated wire cores arranged horizontally in a row, with a flat rubber or plastic sheath on the outside. It has a coated structure.

By the way, in the above-mentioned flat flexible cable, it may be required to apply a shield layer to both side twisted insulated wire cores in the above-mentioned horizontally single-row twisted insulated wire core. However, the above-mentioned twisted insulated wire cores on both sides are located at the position where they receive the greatest torsional strain due to twisting of the flat cable, and the above-mentioned shield layer covering these twisted insulated wire cores is If a fine metal wire braided layer, which is a normal shielding layer, is used, the frictional shear slip between the braided layer and the cable sheath due to the large torsional strain described above will cause
If the above-mentioned cable twisting is repeated frequently, there is a risk that the braided layer will be worn out and damaged at an early stage.

The flat flexible cable according to the present invention has a structure that can eliminate the above-mentioned disadvantages, and is made by arranging a plurality of twisted insulated wire cores in a horizontal line and covering the outside with a flat sheath. In flat flexible cables,
Among the twisted insulated wire cores arranged horizontally in a single row, the ground wire cores are twisted into the twisted insulated wire cores located on both sides which are subjected to maximum torsional strain when the cable is used. It is characterized in that a twisted insulated wire core is covered with a shield layer made of semiconductive rubber/plastic material.

The present invention will be explained below with reference to the drawings.

In the figure, reference numerals 1, 1, . . . indicate twisted insulated wire cores, and the insulated wire 11 is made of twisted conductors of thin annealed copper wires coated with plastic, for example, vinyl chloride resin. The above-mentioned twisted insulated wire cores 1, 1... are arranged in a horizontal row, and a ground wire core (twisted conductor of thin annealed copper wire) 12 is twisted into the twisted insulated wire cores 10, 10 on both sides. .

Reference numeral 2 denotes a semiconductive rubber/plastic shield layer coated on the both-side twisted insulated wire core 10, and includes an extrusion coating of semiconductive rubber/plastic (for example, semiconductive vinyl chloride resin), a semiconductive rubber/plastic shield layer, etc.
It can be provided by wrapping plastic tape or the like.

3 is a flat extruded rubber/plastic sheath, such as a vinyl chloride resin sheath.

As mentioned above, in the flat flexible cable according to the present invention, among the twisted insulated wire cores arranged in a row horizontally, the ground wire is connected to the twisted insulated wire cores located on both sides which are subjected to the maximum torsional strain when the cable is used. Since the twisted insulated wire cores of these ground wire cores are covered with a shield layer made of semiconductive rubber or plastic material, the twisted insulated wire cores located on both sides are The existence of the above-mentioned shield layer can sufficiently prevent induction disturbances caused by current flow from other stranded insulated wire cores other than the stranded insulated wire cores located on both sides of the wire. In addition, as the shield layer is made of semiconductive rubber or plastic material as mentioned above, repeated slippage between the shield layer and sheath is a concern when the shield layer is a braided layer of fine metal wires. Early frictional failure of the shield layer due to damage can be effectively avoided. Moreover, since the grounding wire core (that is, the stranded conductor of thin annealed copper wire) for grounding the shield layer is twisted within the twisted insulated wire core as a component core of the twisted insulated wire core, the It is possible to impart extremely good flexibility to the grounding wire core, and in order to prevent induced disturbances in the cable, the grounding wire core can be placed in locations that are advantageous in terms of location, that is, locations that are subject to maximum torsional strain and frequent repeated torsional stress during use. Even if it is located on the side, a sufficiently long life can be achieved.

In addition, in the flat flexible cable of the present invention, if the shield layer and sheath are made of the same material (vinyl chloride resin) as described in the example, the frictional stress generated at the interface between the two can be completely ignored, so the cable installation is easy. This has the advantage that the allowable bending radius (for example, the allowable bending radius when suspending and laying an elevator power supply cable in a U-shape) can be reduced, which is advantageous in terms of installation space.

[Brief explanation of the drawing]

The drawing is an explanatory cross-sectional view of a flat flexible cable according to the present invention. In the figure, 1, 1... are twisted insulated wire cores, 1
0 and 10 are double-sided insulated wire cores, 2 and 2 are semiconductive rubber/plastic shield layers, and 3 is a flat sheath.

Claims (1)

[Scope of utility model registration request] In a flat flexible cable formed by arranging a plurality of stranded insulated wire cores in a horizontal row and covering the outside with a flat sheath, use of the cable among the stranded insulated wire cores arranged in a horizontal row Ground wire cores are twisted into the twisted insulated wire cores located on both sides, which are sometimes subject to maximum torsional strain, and these twisted insulated wire cores are made of semiconductive rubber or plastic material. A flat flexible cable characterized by being coated with a shield layer.