JPH0145185B2 - - Google Patents

Description

[Detailed description of the invention] This invention relates to a wiring duct.

When wiring lighting equipment, etc. using duct wiring, in addition to the power supply line installed in the duct, signal lines for control, monitoring, and other purposes are installed, but conventionally, signal-only electric wires ( (in most cases, shielded wires) are arranged in parallel to the duct, or as the duct, as shown in Figure 1, a branch wall 2 is used to divide the inside of the housing 1 into a power line installation space A and a signal line installation space. Measures such as adopting a system that is divided into B and B have been used.

However, in order to secure a signal line, installing signal-only electric wires in parallel in addition to the duct as described above does not allow for flexibility in branching positions for power line installation.
The advantages of using ducts, which are easy to install and have excellent ability to hold load equipment, are not fully utilized, and not only are they uneconomical, but depending on how the signal lines are wired, the finished appearance of the equipment is impaired. A drawback arises.

In addition, in an example using a duct in which the inside of the housing 1 is partitioned by the branch wall 2, the inside of the housing 1, which has a U-shaped cross section and is made of a conductive material such as aluminum, is
Branch wall 2 protruding parallel to both sides from the bottom part
Since the structure is divided into two spaces A and B, the structure is similar to that of two normal wiring ducts installed side by side, and the cross-sectional area of the duct increases.

There are now multiple connection structures for devices such as jointers and feed-ins that are connected to ducts and used to connect ducts to each other or to connect ducts to external circuits.
Increase in size.

The structure of the branching plug and the holding structure for holding this branching plug in the duct also become complicated.

It has disadvantages such as poor workability, economical efficiency, poor finished appearance, etc.

Therefore, an object of the present invention is to provide a wiring duct which can house a signal line and a power line compactly in one housing without causing operational problems between them, and which is also excellent in construction and economy. The goal is to provide the following.

An embodiment of this invention is shown in FIG. That is, this wiring duct is made of a conductive material such as steel and has a U-shaped cross section, and has lip portions 3a, 3a formed at the opening edges and branch walls 3b, 3b protruding from the inward surfaces of both sides. A shield core material 3 in which inwardly opened concave grooves 4 having a U-shaped cross section are distributed in two stages from the bottom to the opening, and a housing 5 that covers the entire surface of the shield core material from the outer periphery to the inner periphery. an insulating sheath 6 made of resin or the like that forms a It consists of conductor lines 8a and 8b attached to the insulating sheaths 7 and extending in the longitudinal direction of the housing 5.

In this wiring duct, among the conductor lines 8a and 8b arranged in two stages from the bottom side of the housing 5 toward the opening side, for example, the conductor line 8b on the bottom side is used as a signal line, and the conductor line on the opening side 8a is used as a power supply line, and during installation, the shield core material 3 is grounded via a ground wire.

In this way, a plurality of stages (two stages in this example) of grooves 4, 4 partitioned by the lip portion 3a and the branch wall 3b are formed on the inner surface of both sides of the housing 5. A conductor line 8b for signal transmission and a conductor line 8a for power supply are provided by the protruding insulating sheath 7.
Since the conductor line 8a, with the shield core material 3 grounded,
The electrostatic coupling state between the conductor lines 8a and 8b can be represented schematically as shown in FIG.
It is possible to measure the effective electrostatic resistance between the two.

That is, in FIG. 3, the lines of electric force coming out from the electric charge Q of the conductor line 8a end at the ground plane E and the conductor line 8b, and the electrostatic capacitance C _ab between the conductor lines 8a and 8b and the conductor line 8a. The capacitance C _a between the ground plane E is charged, but the groove 4 having a U-shaped cross section formed by the shield core material 3
(the concave groove of the shield core material 3 is grounded), the conductor lines 8a, 8 are surrounded by
Most of the lines of electric force radiated between the conductor line 8a and the groove 4 end at the groove 4, which has a U-shaped cross section, and only a part of it reaches the conductor line 8b. Since the groove 4 is grounded, the capacitance C _as is parallel to the capacitance C _a between the conductor line 8a and the ground plane E (Similarly, the capacitance C bs between the conductor line 8b and the groove 4 _is is parallel to the capacitance C _b between the conductor line 8b and the ground plane E), and the coupling capacitance between the conductor lines 8a and 8b can be reduced.

Incidentally, if the groove 4 having a U-shaped cross section and which is formed by a part of the shield core material 3 does not exist, the coupling capacitance between the conductor lines 8a and 8b will be equal to each electrostatic capacitance surrounded by the imaginary line in FIG. It can be seen that the coupling capacitance is composed of capacitances C _ab , C _bs , and C _as , and that the interposition of the groove 4 reduces the coupling capacitance by the amount of C _as and C _bs .

By reducing the capacitance of capacitive coupling in this manner, it is possible to prevent the occurrence of inductive disturbances between the conductor lines 8a and 8b due to capacitive coupling (such as noise from the power supply line being picked up by the signal transmission conductor line). be able to.

Furthermore, since the current flowing through the conductor line 8a and the induced current flowing through the groove 4 of the shield core material 3 surrounding it are in opposite directions, the lines of magnetic force caused by this induced current and the lines of magnetic force generated from the conductor line 8a are different from each other. cancel each other out, and can also have an electromagnetic shielding effect on the conductor line 8a. That is, the lines of magnetic force due to the groove 4 are caused by a small current induced in proportion to the part of the magnetic force lines of the conductor line 8a that passes outside the groove 4, and are relatively small, but most of them are caused by the line of force generated by the groove 4. 4, it is possible to sufficiently cancel out some magnetic lines of force of the conductor line 8a passing outside the groove 4, thereby producing an electromagnetic shielding effect.

In addition, such a configuration provides the following effects.

Rather than partitioning the middle part of the bottom of the duct, the inward facing surfaces on both sides are partitioned into multiple stages.
The cross-sectional shape of the duct is simplified and can be configured compactly.

The connection structure of devices such as jointers and feed-ins that are connected to the ducts and are used to connect the ducts to each other or to connect the ducts to an external circuit can be simplified, and these devices can be made compact.

The branch plug can also be held in the duct with a simple connection structure.

Each of the above advantages improves workability and economy.

As described above, the wiring duct of the present invention includes a pair of separated and opposing branch walls formed by folding the flanges doubly on the inner surfaces of both flanges of a rip-groove conductor shield core material, and This is because it is equipped with a housing provided with an insulating coating on the entire surface of the material, an insulating sheath protruding from the inner surface of the flange of this housing located on both sides of the branch wall, and a conductor line attached to the insulating sheath. In addition, the signal line and the power line can be disposed compactly in one housing without causing operational problems between them, and it is also possible to improve workability and economic efficiency. In particular, since the pair of opposing branch walls are separated, they do not get in the way when connecting the plug to the conductor line on the back side. Therefore, even though the branch wall is provided, the plug can be freely connected anywhere in the longitudinal direction of the duct. Moreover, since the branch wall is formed by folding the shield core material twice,
It has the advantage of being easy to manufacture.

[Brief explanation of drawings]

FIG. 1 is a sectional view showing a conventional example, FIG. 2 is a sectional view showing an embodiment of the present invention, FIG. 3 is a schematic diagram showing the state of capacitive coupling between the two conductor lines, and FIG. FIG. 3 is a schematic diagram showing a state of electrostatic bonding when the shield core material does not have a groove. 3... Shield core material, 3a... Lip portion, 3b...
Branch wall, 4... Concave groove (shield concave groove), 5... Housing, 6... Insulating coating, 7... Insulating sheath, 8a, 8
b...Conductor line.

Claims (1)

[Claims] 1 A housing in which a pair of separated and opposing branch walls formed by folding the flanges doubly are provided on the inner surfaces of both flanges of a rip-groove conductor shield core material, and an insulating coating is provided on the entire surface of the shield core material. A wiring duct comprising: an insulating sheath protruding from the inner surface of the flange of the housing on both sides of the branch wall; and a conductor line attached to the insulating sheath.