JPH0130737Y2 - - Google Patents

Description

[Detailed Description of the Invention] This invention relates to a coaxial multicore flat cable with good shape retention, in which a plurality of coaxial cables arranged in parallel are sandwiched between film-like jackets.

With the advancement of technology in recent years, coaxial flat cables, in which multiple shielded wires (or coaxial wires with specified characteristic impedance) are arranged side by side, are used for automatic control of equipment and other purposes. There is.

A metal tube or a braided conducting wire can be used as a shield body for this shielded wire, but if the insulated wire placed in the center is thin, a metal tube or a braided conducting wire cannot be used due to processing considerations. Therefore, in such a case, a horizontally wound shield conductor wire that is wound around the outer periphery of the insulated wire is used. In this case, a plurality of thin conductors are used as the shield conductor, and the smaller the diameter of the thin wire, the more advantageous it is in various aspects. However, because it is difficult to obtain the required thin wire due to processing problems, etc., a shielded conductor wire with a diameter larger than a certain value is used. Therefore, in the conventional coaxial flat cable of this type, a plurality of shielded wires wound in a single direction around the outer circumference of an insulated wire are arranged side by side and covered with an insulating film or the like to form an integrated coaxial flat cable. was. However, in this type of conventional coaxial flat cable, the shield conductor of each shield conductor is wound in only one direction, so the forces inherent in each shield conductor are overlapped by the winding of the shield conductor. As a result, the coaxial flat cable becomes wavy and has poor self-shape maintenance, especially when the outer sheath is a thin film.
Therefore, although such conventional coaxial flat cables do not pose a problem if at least both ends are held in a stationary part and conductively connected, it is not possible to keep both ends conductively connected, as is required in many cases. When using a coaxial flat cable in a freely movable state, there are drawbacks such as excessive tensile stress being generated on certain shielded wires due to cable waving or cable tilting in one direction, leading to disconnection accidents. Ta.

These drawbacks of conventional coaxial flat cables are especially serious when used between devices that are displaced, and as the devices are displaced, the internal force of the cable can cause the cable to twist or collapse. There was a risk that the wire would become wedged into the equipment or break.

Therefore, the object of this invention is to eliminate the above-mentioned drawbacks of the conventional cables, reduce or cancel out the inherent forces, and provide a film-like jacketed coaxial flat cable with good self-shape maintenance properties.

Therefore, according to this invention, a shield conductor is wound around the outer periphery of the insulated wire in one winding direction, and an insulating tape is wound around the outer periphery of the shield conductor layer in a direction opposite to the winding direction of the shield conductor layer. a first shielded wire, a shielded wire is wound around the outer periphery of the insulated wire in the other winding direction, and an insulating tape is wound around the outer periphery of the shielded wire layer in a direction opposite to the winding direction of the shielded wire layer. A coaxial flat cable is formed, comprising a second shielded wire, and a film-like jacket that juxtaposes the same number of the first shielded wire and the second shielded wire. Here, since the insulating tape of each shield wire is wound in the opposite direction to the winding direction of the shield conductor, the self-holding force of the insulating tape is increased, and the return force of the screw winding of the shield conductor increases. This is advantageous because the force (rotational moment) generated in each shielded wire is significantly reduced. Furthermore, if the first shielded wires and the second shielded wires are arranged alternately, the same number of wires are arranged symmetrically, or they are arranged in a mixed manner, in addition to the effect of reducing local stress by pressing and winding the insulating tape, , the inherent stress remaining in each shielded wire is effectively mutually reduced or canceled out in the extending direction of the cable between the first shielded wire and the second shielded wire whose winding directions of the shielded wire are different, and therefore, it is not possible to use the shielded wire. The result is a cable with excellent bending characteristics and torsion resistance, without the occurrence of twisting.

Next, this invention will be explained in more detail with reference to the drawings.

In FIG. 1, a first shielded wire 1 and a second
The coaxial flat cable 4 is arranged in parallel with the shielded wires 2, and is sandwiched and held with the outer periphery surrounded by a film-like jacket 3. As best shown in Figure 2, the first
The shielded wire 1 is an insulated wire 6 having a core wire 5.
A shield conductor layer 8 is formed by winding the shield conductor wire 7 in one direction around the outer circumference of the shield conductor layer 8, and an insulating tape 9 is further wound around the outer circumference of the shield conductor layer 8 in the opposite direction to the winding direction of the shield conductor wire 7. equipped. Second
The shielded wire 2 is formed by winding a shielded wire 7 around the outer periphery of an insulated wire 6 having a core wire 5 in the other direction, and wrapping an insulating tape 9 wound in the opposite direction around the outer periphery.

According to the coaxial flat cable of the present invention having such a structure, a shield conductor is wound in one winding direction, and an insulating tape is wrapped around the outer periphery of the shield conductor layer in a direction opposite to the winding direction of the shield conductor layer. A first shielded wire 1 is wrapped with a first shielded wire 1, and a shielded wire is wound in the other winding direction, and an insulating tape is wrapped around the outer periphery of the shielded wire layer in a direction opposite to the winding direction of the shielded wire layer. As a result of the juxtaposition of the second shielded wire 2, the local stress in each shielded wire caused by the shielded wire is significantly reduced by the insulating tape wound in the opposite direction to the winding direction of the shielded wire layer. In addition, the inherent stress remaining in each shielded wire is mutually reduced or canceled out, and deformation of the cable, such as waving, is no longer caused. At this time, since the insulating tape of each shield wire is wound in the opposite direction to the winding direction of the shield coax, the force generated in each shield wire due to the spiral winding of the shield wire is significantly reduced. In addition, if the first shielded wires and the second shielded wires are arranged alternately, the same number of wires are arranged symmetrically, or they are mixed, the local deformation energy in each shielded wire due to the pressing and wrapping of the insulating tape can be reduced. In addition to the reduction effect, the force remaining in each shielded wire is effectively mutually reduced in the cable extending direction between the first shielded wire and the second shielded wire whose winding directions are different. As a result, the cable does not twist or wave during use, has good self-shape maintenance, and has excellent bending characteristics and twist resistance.

Note that the degree of stress reduction can also be adjusted by appropriately combining the winding direction of the insulating tape in the forward direction with respect to the winding direction of the shield conductor and the winding in the reverse direction.

Furthermore, according to this invention, the insulating tape can be colored differently to facilitate wiring connections.

As described above, according to this invention, the force generated on each shielded wire by the wrapped shielded conductor is reduced by the insulating tape wrapped around the outer periphery of the shielded conductor layer, and furthermore, the shielded wires with different winding directions are arranged side by side. This eliminates the shape-displacement force of the coaxial flat cable by canceling out or attenuating the forces remaining on each shielded wire, so even when it is installed between displaceable devices, it maintains its own shape. This results in an extremely reliable coaxial flat cable that does not suffer from deformation such as twisting without loss. Therefore, the coaxial flat cable of this invention can function as a highly reliable and long-life energizing or signal transmission means even when installed between drive devices, and is of great industrial benefit. There is.

Note that this invention is not limited to the embodiments, and various changes can be made within the scope of the idea of this invention, such as juxtaposing the first shielded wire and the second shielded wire in any combination. Of course there is.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view of a coaxial flat cable according to this invention, and FIG. 2 is a partial plan view of a shielded wire showing an embodiment according to this invention. DESCRIPTION OF SYMBOLS 1...First shielded wire, 2...Second shielded wire, 3...Film-like jacket, 4...Coaxial flat cable, 6...Insulated wire, 7...Shielded conductor wire, 8...Shield Conductor layer, 9...insulating tape.

Claims (1)

[Scope of utility model registration request] A first shielded wire, in which a shielded wire is wound around the outer periphery of the insulated wire in one winding direction, and an insulating tape is wound around the outer periphery of the shielded wire layer in a winding direction different from that of the shielded wire layer; A second shielded wire having an outer periphery wrapped with a shielded wire in the other winding direction and an insulating tape wrapped in a different winding direction than the shielded wire layer, and the first shielded wire and the second shielded wire. A coaxial flat cable comprising a film-like jacket that holds the same number of cables in parallel.