JP3729571B2 - Cable with tube for digital electronic equipment - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a tube capable of suppressing radiation of unnecessary electromagnetic waves from a cable connected to a digital electronic device.
[0002]
[Prior art]
As is well known, a digital electronic device is constituted by a large number of electronic components such as a random access memory (RAM), a read only memory (ROM), and a microprocessor. Each of these electronic components is composed of a large number of logic elements, and these electronic components are mounted on a printed wiring board on which signal lines (wiring conductors) are stretched. In recent digital electronic devices, the operation speed of logic elements can be increased, and the devices are rapidly becoming lighter, thinner and smaller. Along with this, the mounting density of electronic components on a printed wiring board has been dramatically increased.
[0003]
However, since the signal flowing through the logic element is accompanied by a rapid change in voltage and current, the electronic component is a source of high-frequency noise. This high-frequency noise interacts synergistically with crosstalk noise and noise due to impedance mismatching, causing malfunctions to other electronic components in the printed wiring board and adversely affecting other systems. Furthermore, with the high density mounting of electronic components on a printed circuit board and the miniaturization of electronic components, electrostatic coupling between electronic components increases, and electromagnetic interference in digital electronic devices is likely to occur. .
[0004]
A digital electronic device that becomes such a noise generation source is connected to another digital electronic device, a power outlet, or the like via a cable.
[0005]
[Problems to be solved by the invention]
Therefore, there is a possibility that unnecessary electromagnetic waves are radiated from the cable. Since this unnecessary electromagnetic wave has an adverse effect on other electronic devices, it is necessary to suppress it. However, conventionally, no countermeasure is taken against unnecessary electromagnetic waves radiated from the cable.
[0006]
Accordingly, an object of the present invention is to provide a composite magnetic tube, a manufacturing method thereof, and an electromagnetic interference suppression tube that can be used for suppressing radiation of unnecessary electromagnetic waves from a cable connected to a digital electronic device. .
[0007]
When wiring a plurality of vinyl-coated wires (cables), it is common to bundle them with a bundle band or spiral tube. In this case, power supply lines and signal lines are often mixed. When mixed wiring is used, an electrical signal is deteriorated due to increase or induction of crosstalk, and the circuit may malfunction due to this.
[0008]
Another object of the present invention is to provide a composite magnetic tube, a manufacturing method thereof, and an electromagnetic interference suppression tube that can suppress mutual interference even when a plurality of vinyl-coated electric wires (cables) are bundled. There is to do.
[0009]
[Means for Solving the Problems]
In order to solve the above problems, according to the first aspect of the present invention, a composite magnetic material tube made of a material obtained by kneading and dispersing soft magnetic material powder in an organic binder is obtained.
[0010]
In the composite magnetic tube, the organic binder is preferably an elastomer. The soft magnetic powder is preferably a substantially flat powder. Furthermore, it is desirable that a slit be cut along the longitudinal direction of the composite magnetic tube. Such a composite magnetic tube can be produced by an extrusion method.
[0011]
According to the second aspect of the present invention, the composite magnetic tube is made of a material obtained by kneading and dispersing soft magnetic powder in an organic binder, and the conductive material is provided on the outer wall of the composite magnetic tube. An electromagnetic interference suppression tube having a shield tube is obtained.
[0012]
In the electromagnetic interference suppression tube, the organic binder is preferably an elastomer. The soft magnetic powder is preferably a substantially flat powder. Furthermore, the shield tube may be composed of a conductive thin wire. It is desirable that the slit is cut along the longitudinal direction of the electromagnetic interference suppression tube.
[0013]
[Action]
By covering the cable radiating unnecessary electromagnetic waves with the composite magnetic material tube or the electromagnetic interference suppressing tube according to the present invention, it is possible to suppress radiation of unnecessary electromagnetic waves from the cable. By cutting a slit along the longitudinal direction of the composite magnetic tube or electromagnetic interference suppression tube, the composite magnetic tube or electromagnetic interference suppression tube can be easily attached to the cable.
[0014]
DETAILED DESCRIPTION OF THE INVENTION
Next, the present invention will be described in detail with reference to the drawings.
[0015]
With reference to FIG. 1, the composite magnetic material tube 10 by the 1st Embodiment of this invention is comprised with the material which knead | mixed and disperse | distributed the soft-magnetic-material powder 12 in the organic binder 14. As shown in FIG. As the organic binder 14, it is preferable to use an elastomer having a good stretch property. The soft magnetic powder 12 is preferably a substantially flat powder.
[0016]
Examples of the organic binder 14 include thermoplastic resins such as polyester resins, polyvinyl chloride resins, polyvinyl butyral resins, polyurethane resins, cellulose resins, nitrile-butadiene rubbers, styrene-butadiene rubbers, and polymers thereof. Can be mentioned.
[0017]
Typical examples of the soft magnetic powder 12 include iron-aluminum-silicon alloy (which is called Sendust (trademark)) and iron-nickel alloy (permalloy) having a high high-frequency magnetic permeability. The soft magnetic powder 12 is finely powdered and used after oxidizing the surface portion. The aspect ratio of the soft magnetic powder 12 is desirably sufficiently large (for example, approximately 5: 1 or more).
[0018]
Such a composite magnetic tube 10 can be produced by an extrusion molding method. That is, by using an extruder (not shown), a composite magnetic body is obtained by extruding a material obtained by kneading and dispersing soft magnetic powder 12 in an organic binder 14 from a die (not shown). The tube 10 is formed.
[0019]
This composite magnetic material tube 10 is used by covering a cable (not shown) that radiates unnecessary electromagnetic waves. Thereby, the unnecessary electromagnetic wave radiated | emitted from the cable is absorbed by the soft-magnetic-material powder 12, and the radiation of the unnecessary electromagnetic wave from a cable can be suppressed. Further, by making the shape of the soft magnetic powder 12 substantially flat, unnecessary electromagnetic waves radiated from the cable can be absorbed and suppressed more efficiently. This is because, when the shape of the soft magnetic powder 12 is substantially flat, shape anisotropy appears and complex permeability based on magnetic resonance increases in a high frequency region.
[0020]
Referring to FIG. 2, the composite magnetic tube 10A according to the second embodiment of the present invention is shown in FIG. 1 except that the slit 16 is cut along the longitudinal direction of the composite magnetic tube 10A. The composite magnetic material tube 10 has the same configuration.
[0021]
The composite magnetic tube 10A having such a structure exhibits the same electromagnetic wave absorption effect as the composite magnetic tube 10 shown in FIG. Moreover, since the slit 16 is cut in the composite magnetic tube 10A, the composite magnetic tube 10A can be easily attached to the cable.
[0022]
Referring to FIG. 3, the electromagnetic interference suppression tube 20 according to the first embodiment of the present invention includes a composite magnetic tube 10 and a shield tube 30 made of a conductive material provided on the outer wall of the composite magnetic tube 10. Consists of Since the structure of the composite magnetic tube 10 is the same as that shown in FIG. 1, the description thereof is omitted.
[0023]
The shield tube 30 may be composed of conductive thin wires (mesh wires), or may be formed by metal plating.
[0024]
The electromagnetic interference suppression tube 20 having such a configuration not only exhibits an electromagnetic wave absorption effect similar to that of the composite magnetic material tube 10 illustrated in FIG. 1, but also exhibits an electromagnetic wave shielding effect based on the shield tube 30. In addition, electromagnetic waves can be shielded more efficiently by grounding the shield tube 30.
[0025]
Referring to FIG. 4, the electromagnetic interference suppression tube 20A according to the second embodiment of the present invention is shown in FIG. 3 except that the slit 16 is cut along the longitudinal direction of the electromagnetic interference suppression tube 20A. The electromagnetic interference suppression tube 20 has the same configuration. The electromagnetic interference suppression tube 20A includes a composite magnetic tube 10A and a shield tube 30A.
[0026]
The electromagnetic interference suppression tube 20A having such a structure exhibits an electromagnetic wave absorption effect and an electromagnetic wave shielding effect, similarly to the electromagnetic interference suppression tube 20 shown in FIG. Further, since the slit 16 is cut in the electromagnetic interference suppression tube 20A, the electromagnetic interference suppression tube 20A can be easily attached to the cable.
[0027]
FIG. 5 shows an application example of the tube 40 according to the present invention. The illustrated tube 40 may be the composite magnetic tube 10 shown in FIG. 1, the composite magnetic tube 10A shown in FIG. 2, the electromagnetic interference suppression tube 20 shown in FIG. 3, or the electromagnetic shown in FIG. The interference suppression tube 20A may be used.
[0028]
The illustrated application example shows an example in which a plurality of (in this example, five) vinyl-coated electric wires 51, 52, 53, 54, and 55 are bundled with a bundle band 60. In the illustrated example, the two vinyl-coated electric wires 51 and 52 are power lines, and the remaining three vinyl-coated electric wires 53 to 55 are signal lines. These five vinyl-coated electric wires 51 to 55 extend from the connector 70 and are bundled by the bundle band 60 in the middle. When power supply lines and signal lines are mixedly wired in this way, as described above, there is a possibility that an interaction occurs and the circuit malfunctions. In order to suppress such interaction between the vinyl-coated electric wires 51 to 55, the tubes 40 are attached to the respective vinyl-coated electric wires 51 to 55.
[0029]
Although the present invention has been described with reference to several embodiments, the present invention is not limited to the above-described embodiments, and various modifications can be made without departing from the scope of the present invention. Absent.
[0030]
【The invention's effect】
As described above, by covering the tube (composite magnetic material tube or electromagnetic interference suppression tube) according to the present invention with a cable that radiates unnecessary electromagnetic waves, it is possible to suppress the radiation of unnecessary electromagnetic waves from the cable. it can. Moreover, a tube can be easily attached to a cable by cutting a slit along the longitudinal direction of the tube. Furthermore, the influence of radiation noise from the outside can be shielded by using a combined structure of a composite magnetic tube and a shield tube.
[Brief description of the drawings]
FIG. 1 is a perspective view showing a composite magnetic material tube according to a first embodiment of the present invention.
FIG. 2 is a perspective view showing a composite magnetic material tube according to a second embodiment of the present invention.
FIG. 3 is a sectional view showing an electromagnetic interference suppressing tube according to the first embodiment of the present invention.
FIG. 4 is a cross-sectional view showing an electromagnetic interference suppression tube according to a second embodiment of the present invention.
FIG. 5 is a perspective view showing an application example when a plurality of vinyl-coated electric wires are bundled with a bundle band in a tube according to the present invention.
[Explanation of symbols]
10, 10A Composite magnetic tube 12 Soft magnetic powder 14 Organic binder 16 Slit 20, 20A Electromagnetic interference suppression tube 30, 30A Shield tube

Claims (2)

In cable digital electronic device connected to a digital electronic device, in an organic binder consisting of elastomers comprising a thermoplastic resin or a polymer thereof, a flat soft magnetic alloy powder obtained by oxidizing a surface portion was kneaded and dispersed Cable with a tube for digital electronic equipment, characterized by covering a composite magnetic tube made of different materials. In cable digital electronic device connected to a digital electronic device, in an organic binder consisting of elastomers comprising a thermoplastic resin or a polymer thereof, a flat soft magnetic alloy powder obtained by oxidizing a surface portion was kneaded and dispersed With a tube for digital electronic equipment, characterized by covering a composite magnetic tube made of the above material and an electromagnetic interference suppression tube constructed by laminating a shield tube made of a conductive material on the outer wall of the composite magnetic tube cable.

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