JP2016127054A - Shield material for connector/cable - Google Patents

Abstract

PROBLEM TO BE SOLVED: To allow for shielding of a cable and a connector, regardless of the shape and size of a connector connected.SOLUTION: A shield material for connector/cable composed of a conductive cloth-like body, and shielding the connector and the connector connection part of a cable 600 for connection with the connector, has a connector cover 110 covering the connector, and a cable cover 120 covering the cable 600. The connector cover 110 and cable cover 120 are coupled, a warp thread 150 constituting the conductive cloth-like body is composed of a conductive material, and a weft thread 160 is composed of a heat shrinkable polyester yarn.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a cable having a connector connected to a terminal end and a shield material for a connector / cable that blocks noise from around the connector.

  As this type of shielding material, there is one in which metal yarns are knitted into a tube shape. A cable is inserted through this shield material to block noise from the cable.

A connector is connected to the end of the cable. Since this connector is larger than the cable, the shield material is generally connected to the connector in an expanded state.
For this reason, at the terminal end of the cable, that is, at the connection portion to the connector, the gap between the metal threads constituting the shield material becomes larger than the other portions, and there is a problem that noise leakage tends to occur from there.

  In order to solve such a problem, “a shield member that is formed as a braided wire in which strands are woven, covers and shields a plurality of electric wires, and has a flat cross section and a flat portion of the strands. A shield member in which a flat surface is formed to be flat along the surface of the braided wire is disclosed in Japanese Patent Laid-Open No. 2012-169497.

JP 2012-169497 A

However, in order to make the cross section of the wire flat and make the flat surface of the wire flat along the surface of the braided wire, this shield member can Step 1 and a second step of pressing the expanded portion of the strands so as to be flat along the surface of the braided wire.
That is, it is necessary to perform a diameter expansion process (first process) and a pressing process (second process) so as to correspond to the shape of the connector to be connected. In addition, a jig corresponding to the shape and size of the connector is required in each process.
That is, with the shield member described in Patent Document 1, two processing operations are required depending on the shape of the connector, and many jigs corresponding to the shape and size of the connector must be prepared. There is a problem.

  The present invention was devised in view of the above circumstances, and provides a connector and a shield material for a cable that can shield a connector regardless of the shape and size of the connector. The purpose is to do.

  The connector / cable shielding material according to the present invention is composed of a conductive cloth-like body, and is a connector / cable shielding material that shields a connector and a connector connecting portion of a cable connected to the connector. The connector cover portion covers the connector, and the cable cover portion covers the cable. The connector cover portion and the cable cover portion are connected to each other.

  In addition, at least one of the warp and the weft constituting the conductive cloth-like body is made of a conductive material.

  In addition, the material having conductivity is a synthetic resin yarn covered with a conductive metal foil.

  In addition, at least one of the warp and the weft constituting the conductive cloth-like body has heat shrinkability.

  Since the connector / cable shield material according to the present invention covers the connector by the connector cover part and the cable by the cable cover part, it is necessary to cover the connector with the connector cover part covering the connector expanded. Absent. For this reason, since the clearance gap between the metal threads which comprise a shielding material does not become larger than another part, a possibility that noise leakage will generate | occur | produce from there reduces.

It is a schematic plan view of the state which expanded the shield material for connectors and cables concerning an embodiment of the invention. It is a schematic perspective view of the state which covered the connector and the cable with the shield material for connectors and cables concerning an embodiment of the invention. It is a schematic partial enlarged plan view of the conductive cloth-like body constituting the connector / cable shield material according to the embodiment of the present invention. It is a schematic near field measurement result figure which shows the electromagnetic wave shielding effect of the shield material for connectors and cables concerning an embodiment of the invention. It is a schematic near field measurement result figure which shows the electromagnetic wave shielding effect of the shield material for connectors and cables concerning an embodiment of the invention. It is a schematic far-field measurement result figure which shows the electromagnetic wave shielding effect of the shield material for connectors and cables which concerns on embodiment of this invention.

  A connector / cable shield material 100 according to an embodiment of the present invention is composed of a conductive cloth-like body, and shields a connector and a connector connecting portion of a cable 600 connected to the connector. The shield member includes a connector cover portion 110 that covers the connector, and a cable cover portion 120 that covers the cable 600, and the connector cover portion 110 and the cable cover portion 120 are connected to each other. Yes. In FIG. 2, the connector and the connector connecting portion are not visible because they are covered with the connector / cable shield material 100.

As shown in FIG. 3, the conductive cloth-like body is configured by weaving warps 150 and wefts 160. Here, the longitudinal direction of the connector / cable shield material 100, that is, the yarn along the cable 600 is defined as the warp yarn 150, and the yarn orthogonal to the cable 600 (the yarn along the short direction of the connector / cable shield material 100) is used. The weft thread 160 is used.
The warp yarn 150 is made of a conductive material. The warp yarn 150 is composed of a synthetic resin yarn and a conductive metal foil having conductivity that covers the surface layer of the synthetic resin yarn. Polyester yarn is used as the synthetic resin yarn, and copper foil is used as the conductive metal foil covering the polyester yarn.

  On the other hand, the weft thread 160 does not have conductivity, and is made of a polyester thread having heat shrinkability. Since the weft yarns 160 are arranged in a direction perpendicular to the warp yarns 150, they are arranged along the short direction of the connector / cable shield material.

  In addition, the thickness of the warp 150 which comprises an electroconductive cloth-like body is 0.7 mm, the pitch of the warp 150 is 1.17 mm, the thickness of the weft 160 is 0.2 mm, and the pitch of the weft 160 is 1.02 mm8. . Moreover, the thickness dimension of this conductive cloth-like body is 0.8 mm. It should be noted that the thickness, pitch, and thickness dimensions of the weft 160 and warp 150 are merely examples, and the present invention is not limited thereto.

  As shown in FIG. 1, the connector cover part 110 is formed in a substantially rectangular shape corresponding to the size of the connector to be surrounded. Therefore, the connector cover portion 110 can completely wrap the connector.

Meanwhile, the cable cover part 120 is a rectangular body protruding from the connector cover part 110. Since the cable 600 connected to the connector is thinner than the connector, if the width of the cable 600 is the same as that of the connector cover portion 110, an extra portion will come out even if the cable 600 is wrapped, and even if the cable 600 is to be covered by that portion. , Gaps are created and complete shielding becomes impossible.
Further, the cable cover portion 120 is brought into conduction by being in contact with a conventional shield material (metal yarn knitted into a tube shape) that shields most of the cable 600.

  The cable cover 120 covers the cable 600 and the connector connecting portion which is also a portion connected to the connector. The cable cover portion 120 is formed in a shape that can cover the cable 600 without any excess. The cable cover 120 is tightened with a fastening member such as a binding band as necessary so that the cable cover 120 does not come off the cable 600 (in FIG. 2, a fastening member such as a binding band is not used). Note that a fastening member such as a binding band is used when there is a movable part or a vibrating part, or when the surface of the cable 600 is slippery.

In this manner, the connector and the connector connecting portion of the cable 600 connected to the connector can be covered with the connector / cable shield material 100 along these shapes. For this reason, when this connector / cable shield material 100 is used, noise leakage caused by the fact that the gap between the metal threads of the connector portion becomes larger than the other portions as in the prior art does not occur.
In particular, the weft thread 160 is made of a heat-shrinkable polyester-based thread, so that the connector and cable shield material 100 covers the connector and the cable 600 and then contracts when heat is applied. Since the cable 600 is in close contact with the shape of the cable 600, the shielding performance is improved. That is, since this connector / cable shield material 100 has self-winding properties, it can be grounded 360 degrees on the connector and cable 600 (wraps over the entire 360 degrees), so that high shielding performance can be obtained. Can do it.
Further, the connector / cable shield material 100 has an advantage that a separate mounting member such as a hook or a hook-and-loop fastener is not required.

Further, the connector covered with the connector cover part 110 and the connector connecting part of the cable 600 covered with the cable cover part 120 are covered with an insulator cover (not shown).
In this insulator cover, a large diameter portion capable of covering the connector together with the connector cover portion 110 and a small diameter portion capable of covering the connector connecting portion of the cable 600 together with the cable cover portion 120 are continuously formed. It is integrally molded with an insulator such as synthetic rubber.

In order to confirm the shielding effect of the connector / cable shielding material 100 thus configured, the following experiment was conducted.
Connect a connector to one end of the cable 600, and measure near-field magnetic field leakage from the cable 600 in the range of 235mm from this connector at 47 places in 5mm pitch and 5 places in 5mm pitch. did. The vertical direction refers to a direction along the cable 600, and the horizontal direction refers to a direction orthogonal to the cable 600. Measurement was performed at 1 MHz and 80 MHz.

  4A shows a case where there is no shield material, FIG. 4B shows a case where the same part (B) is covered with a conventional shield material, and FIG. 4C shows a connector / cable shield according to an embodiment of the present invention. In this case, the frequency is 1 MHz. A connector is connected to the left side of the drawing.

  According to FIG. 4A, when there is no shielding material, an electromagnetic wave of 18 to 24 dBμV is observed over the entire central portion. In particular, an electromagnetic wave of 22 to 26 dBμV is observed near the connector. Note that an electromagnetic wave of 10 to 12 dBμV is observed in the portion farthest in the horizontal direction.

  On the other hand, according to FIG. 4B, the electromagnetic wave of 0 to 4 dBμV is observed as a whole in the case covered with the conventional shielding material, but it is sporadically 6 to 8 dBμV and 8 to 10 dBμV particularly in the portion close to the connector. Is observed. It is estimated that this is because the gap between the metal threads constituting the shield material to cover the connector is larger than the other parts.

On the other hand, as shown in FIG. 4 (C), an electromagnetic wave of 0 to 4 dBμV is observed as a whole from the connector covered with the connector / cable shield material 100 according to the embodiment of the present invention. It can be seen that only 6-8 dBμV electromagnetic waves are observed sporadically at a distant position, and only 10 dBμV electromagnetic waves are not observed.
This is presumably because the cable cover portion 120 of the connector / cable shield material 100 according to the embodiment of the present invention reliably covers the cable 600.

The same experiment was performed at a frequency of 80 MHz.
5A shows a case where there is no shielding material, FIG. 5B shows a case where the same part (B) is covered with a conventional shielding material, and FIG. 5C shows a connector / cable shield according to the embodiment of the present invention. A connector is connected to the left side of the drawing, which is a case where the material 100 is covered.

  According to FIG. 5A, when there is no shielding material, an electromagnetic wave of 44-60 dBμV is observed over the entire central portion. In particular, an electromagnetic wave of 56 to 60 dBμV is observed at a portion close to the connector. Note that an electromagnetic wave of 44 to 48 dBμV is observed even at the most distant portion in the horizontal direction.

  On the other hand, according to FIG. 5 (B), an electromagnetic wave of 0 to 32 dBμV is observed as a whole in what is covered with a conventional shielding material, but an electromagnetic wave of 28 to 36 dBμV is sporadically observed particularly in a portion close to the connector. Is done. Further, an electromagnetic wave of 16 to 28 dBμV is observed along the center of the cable 600. It is estimated that this is because the gap between the metal threads constituting the shield material to cover the connector is larger than the other parts. It should be noted that only 0 to 4 dBμV portions where almost no electromagnetic waves are observed are observed in several points.

On the other hand, in the case covered with the connector / cable shield material 100 according to the embodiment of the present invention, as shown in FIG. It turns out that only an electromagnetic wave of 12 to 16 dBμV is observed in a very small part, and an electromagnetic wave of 16 dBμV or more is not observed.
This is presumably because the cable cover portion 120 of the connector / cable shield material 100 according to the embodiment of the present invention reliably covers the cable 600.

  As described above, in the near-field magnetic field measurement, when the connector / cable shield material 100 according to the embodiment of the present invention is used, the conventional shield material is used as well as the case where no shield material is used. It turns out that the shielding effect of electromagnetic waves is higher than when it is used. Moreover, in this connector / cable shield material 100, it was also confirmed that the higher the frequency, the higher the electromagnetic wave shielding effect.

FIG. 6 is a graph showing the far-field magnetic field measurement results.
According to this graph, it can be confirmed that the shield material 100 for connector and cable according to the embodiment of the present invention and the conventional shield material have substantially the same shielding effect at 1 MHz or less, but beyond that, It can be confirmed that the shield effect 100 of the connector / cable according to the embodiment of the present invention has a shield effect higher by 10 dB or more than the conventional shield material.
Of course, it can also be confirmed that the shielding effect is 30 dB or more higher than when no shielding material is used.
The reason why the graph is interrupted at 30 MHz is that the antenna for detecting electromagnetic waves has been changed at 30 MHz.

In the above-described embodiment, of the warp yarns 150 and the weft yarns 160 constituting the conductive cloth-like body, the warp yarns 150 are made of a conductive material, and the weft yarns 160 have a heat-shrinkability that is not conductive. However, the present invention is not limited to this.
Only the warp 150 may be heat-shrinkable, or only the weft 160 may be conductive. Needless to say, both the warp yarn 150 and the weft yarn 160 may be heat-shrinkable and conductive.

  In addition, the weft thread 160, which is the conductive material, is a synthetic resin thread covered with a conductive metal foil (copper foil). However, any material having conductivity may be used. Needless to say, it is good.

100 Connector / Cable Shield Material 110 Connector Cover Part 120 Cable Cover Part 150 Warp Thread 160 Weft

Claims (3)

  In a connector / cable shielding material that is composed of a conductive cloth-like body and shields a connector and a connector connecting portion of a cable connected to the connector, a connector cover portion that covers the connector and covers the cable A cable cover portion, the connector cover portion and the cable cover portion are connected to each other, and at least one of the warp yarn and the weft yarn constituting the conductive cloth-like body is made of a conductive material. Shielding material for connectors and cables, characterized by   2. The connector / cable shield material according to claim 1, wherein the conductive material is a synthetic resin yarn covered with a conductive metal foil.   3. The connector / cable shielding material according to claim 1, wherein at least one of the warp and the weft constituting the conductive cloth-like body has heat shrinkability.

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