JPH05258620A - Signal cable - Google Patents

Abstract

PURPOSE:To make the external shape of a signal cable compact by keeping the impedance of a core wire in which high speed synchronous signals are stored be a prescribed value and suppressing cross talk as much as possible wherein the signal cable is composed of a coaxial wire and a pair wire or pair wires composed of core wires with different wire diameters. CONSTITUTION:A signal cable is composed by covering two pairs of coaxial wires 1 and a plurality of first wires 2 composed of first core wires 3 having prescribed wire diameter with a shield layer 4.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a signal cable formed by a coaxial wire and a pair wire, or a pair wire composed of core wires having different wire diameters.

When constructing a workstation, a signal cable is laid at the interface between the main unit and the terminal unit, and a control signal is propagated by the signal cable. Such a signal cable is required to satisfy a predetermined condition in electrical characteristics for propagating a control signal, especially as the device speed increases.

[0003]

2. Description of the Related Art Conventionally, the structure is as shown in the conventional explanatory view of FIG. 4A is a sectional view, FIG. 4B is a sectional view of a pair line, and FIG. 4C is a housing diagram of control signals.

As shown in FIG. 4 (a), when forming so as to have 50 connecting lines, it is usually formed by covering 25 pair lines 10 with a shield layer 4. As shown in FIG. 4 (b), the pair wire 10 is a core wire 10A formed by covering the conductor 11 having the wire diameter d12 with the insulator 12 and having the outer diameter d2.
Are formed by pairing.

Therefore, when the interface is used as described above, for example, as shown in FIG. 4 (c), the signal described in the signal name is connected to the line No. of each pair line 10. Was formed.

In this case, the wire diameter d12 of the conductor 11 is 0.38 mm so that the impedance of the pair wire 10 is 100 ohms.
In addition, the outer diameter d2 of the insulator 12 was 0.8 mm. Even in the control signal, the accommodating positions of the -ACK and -REQ signals, which are high-speed synchronization signals, are usually affected by crosstalk. It is considered that by accommodating −REQ signal in No24, the distance as far as possible can be obtained so that they do not come close to each other.

[0007]

It is not possible to form the paired wire 10 by pairing the core wires 10A formed on the outer diameter d2 by covering the conductor 11 having the wire diameter d12 with the insulator 12 as described above. As shown in FIG. 4 (a), when the signal cable is formed by covering the 25 pair wires 10 with the shield layer 4, the outer diameter of the signal cable becomes D and the diameter becomes large.

Therefore, when laying a signal cable,
A large laying space for laying is required, and it is difficult to bend at the time of laying, so that man-hours are required for laying work.

Therefore, by simply reducing the wire diameter d12 so as to reduce the outer diameter D of the signal cable, the impedance in the pair wire 10 exceeds 100 ohms, and the propagation of the high-speed synchronizing signal is increased. However, there is a problem that the electrical characteristics of signal propagation are deteriorated, the above-mentioned distance between the accommodation positions cannot be obtained, and the influence of crosstalk becomes large.

Therefore, in the present invention, the impedance of the core wire in which the high-speed synchronizing signal is accommodated is maintained at a predetermined value,
Moreover, it is intended to reduce the outer shape of the signal cable by suppressing the crosstalk as much as possible.

[0011]

1A and 1B are explanatory views of the principle of the present invention. As shown in FIG. 1A, two sets of coaxial wires 1 and a predetermined wire are provided. A plurality of first paired wires 2 composed of a first core wire 3 having a diameter d1 are covered with a shield layer 4, and as shown in FIG. A plurality of first pair wires 2 consisting of one core wire 3,
The second pair of wires 5 consisting of the second core wire 6 having a wire diameter d2 larger than the wire diameter d1 is covered by the shield layer 4.

The above-mentioned problems can be solved by such a configuration.

[0013]

Operation: That is, it is formed by two sets of coaxial wires 1 and a plurality of first pair wires 2 composed of a first core wire 3 having a small wire diameter d1, or a first wire having a small wire diameter d1. A plurality of first paired wires 2 composed of core wires 3 and two second paired wires 5 composed of a second core wire 6 having a large wire diameter d2.

Therefore, the impedance of the high-speed synchronization signal is set to a predetermined value by accommodating the high-speed synchronization signal in the coaxial line 1 or the second pair line 5 and reducing the diameter of the other first pair line 2. It is possible to reduce the size of the outer shape of the signal cable by keeping the above and suppressing crosstalk as much as possible.

[0015]

The present invention will be described in detail below with reference to FIG.
FIG. 2 is an explanatory view of an embodiment according to the present invention, (a) is a sectional view, (b1) is a sectional view of a coaxial wire, (b2) is a sectional view of a pair wire, (c).
FIG. 3 is an accommodation diagram of control signals, FIG. 3 is an explanatory diagram of another embodiment of the present invention, (a) is a sectional view, and (b) is a sectional view of a pair line. Throughout the drawings, the same reference numerals denote the same objects.

As shown in FIG. 2 (a), two sets of coaxial wires 1
And a plurality of first pair wires 2 are covered with a shield layer 4. Also, the coaxial line 1 is shown in FIG.
As shown in (b1), the conductor 1A having the wire diameter d3 is coated with the insulator 1B, covered with the shield layer 1C, and further covered with the outer cover 1D. of
As shown in (b2), a conductor 3A having a wire diameter d11 is covered with an insulator 3B to form a pair of first core wires 3 having an outer diameter d1.

Therefore, when it is used for the interface as described above, for example, as shown in FIG.
Connect the signal described in the signal name to o. In this case, if the wire diameter d3 of the conductor 1A of the coaxial line 1 is formed to be 0.38 mm, the impedance can be naturally set to 100 ohms, and further, the coaxial line 1 may cause crosstalk between each other. Therefore, the −ACK signal and −REQ signal, which are high-speed synchronization signals, should be connected by coaxial line 1.In particular, for other signals that do not require impedance restriction, the wire diameter d11 should be 0.19. Connection is made by a first bare wire 2 made of a first core wire 3 having a wire diameter d1 of 0.4 mm formed by a conductor 3A reduced to mm.

With this configuration, the outer diameter of the signal cable is D1, which can be made smaller than the outer diameter D of the conventional signal cable. Further, in the case of FIG. 3, it is composed of a plurality of first pair wires 2 formed of a small diameter and having a wire diameter d1 of a first core wire 3 and a second core wire 6 having a wire diameter of d2 larger than the wire diameter d1. The two second pair wires 5 and 5 are formed so as to be covered by the shield layer 4.

In this case, the second pair of wires shown in FIG.
The wire diameter d2 of the second core wire 6 forming 5 is set to 0.8 mm, and the conductor 6A
Since the impedance of the second pair wire 5 can be set to 100 ohms by setting the wire diameter D12 of the wire to 0.38 mm, a high-speed synchronizing signal can be obtained by wires No1 and No-2.
The ACK signal and the -REQ signal are connected by the second pair line 5.

Therefore, the other signals have the wire diameter d11 of 0.
The connection is made by a first bare wire 2 consisting of a first core wire 3 having a diameter d1 of 0.4 mm and a diameter of 19 mm. In this case, it is necessary to make the distance between the accommodation positions of the two pairs of second pair wires 5 as large as possible so that crosstalk does not occur.

Therefore, even with this configuration, the outer diameter of the signal cable can be formed to D2 which is smaller than the outer diameter D of the conventional signal cable. In this way, by propagating the -ACK signal and the -REQ signal of the high-speed synchronization signal by the coaxial line 1 or the second pair line 5, the propagation of the high-speed synchronization signal is not hindered, Moreover, the outer diameter of the signal cable can be reduced.

[0022]

As described above, according to the present invention,
By providing two pairs of coaxial wires or pair wires with a large conductor diameter in a signal cable consisting of pair wires, accommodating high-speed synchronization signals in each, and reducing the core wire of the pair wires accommodating other signals. By making the outer diameter of the signal cable small, even if the outer diameter of the signal cable is small, it is possible to prevent the propagation of the high-speed synchronizing signal from being hindered.

Therefore, the installation space can be reduced and the man-hour for the installation work can be reduced, and the practical effect is great.

[Brief description of drawings]

FIG. 1 is an explanatory view of the principle of the present invention.

FIG. 2 is an explanatory diagram of an embodiment according to the present invention.

FIG. 3 is an explanatory diagram of another embodiment of the present invention.

FIG. 4 is a conventional explanatory diagram

[Explanation of symbols]

1 coaxial cable 2 1st pair wire 3 1st core wire 4 shield layer 5 2nd pair wire 6 2nd core wire

Claims (2)

[Claims] 1. A plurality of first pair wires (2) comprising two sets of coaxial wires (1) and a first core wire (3) having a predetermined wire diameter (d1).
A signal cable formed by covering and with a shield layer (4). 2. A first core wire (3) having a predetermined wire diameter (d1).
A plurality of first pair wires (2), and two pairs of second pair wires (5) having a second core wire (6) having a wire diameter (d2) larger than the wire diameter (d1); A signal cable, characterized in that the signal cable is formed by covering the wire with a shield layer (4).