CN201233756Y - Signal transmission line unit - Google Patents

Abstract

The utility model relates to the technical field of signal transmission lines, and particularly refers to a signal transmission line unit, which comprises a pair of core wires, a ground wire and two layers of aluminum foil Mylar. The outer periphery of the core wire is covered with two layers of aluminum foil Mylar along the length direction of the core wire, one side of the aluminum foil Mylar is a conductive surface, and the other side of the aluminum foil Mylar is an insulating surface. The ground wire is passed between the two layers of aluminum foil Mylar, and the conductive surfaces of the two layers of aluminum foil Mylar are both oriented toward the ground wire. The conductive surfaces of the two layers of aluminum foil Mylar are respectively in electrical contact with the ground wire, which reduces the capacitance of the signal transmission line unit, increases the inductance of the signal transmission line unit, forms a high impedance, and further enables the signal transmission line unit to have good high-frequency performance.

Description

A signal transmission line unit

Technical field:

The utility model relates to the technical field of signal transmission lines, in particular to a signal transmission line unit.

Background technique:

HDMI is a new type of multimedia digital interface, which can provide a transmission rate of up to 10Gbps, and can transmit high-quality video and audio signals that are not compressed and do not need to be converted. The advantage of using HDMI is that only one HDMI signal cable is needed to transmit audio and video signals at the same time, which greatly simplifies the installation of the home theater system.

Usually HDMI signal lines include multiple pairs of signal transmission lines. As shown in Figure 1, a pair of signal transmission lines is composed of a pair of twisted core wires 1, a ground wire 2 and at least one layer of cladding 3. The core wires are composed of conductors 1a and The foamed insulating layer 1b is composed of a foamed insulating layer 1b. The foamed insulating layer 1b will be deformed when being squeezed, and the foamed insulating layer 1b will also be deformed when heated during the welding process, which affects the high-frequency performance of the HDMI signal line. At present, in the high-frequency test, HDMI signal lines with a length of more than 5 meters will have attenuation, poor delay, etc., and the main factors affecting such defects are the size of the core wire conductor, the core wire insulation, and the The way of wrapping and its arrangement. Since the size of the conductor 1a of the core wire 1 cannot be changed arbitrarily, it is only possible to reduce the capacitance of each pair of signal transmission lines and increase its inductance by changing the foamed insulating layer 1b, covering method and arrangement of the core wire 1 to form a high Impedance, so that the signal transmission line has good high frequency performance.

Utility model content:

The purpose of this utility model is to provide a signal transmission line unit for the deficiencies of the prior art, which reduces the capacitance of the signal transmission line unit, increases the inductance of the signal transmission line unit, forms a high impedance, and makes the signal transmission line unit have good high frequency performance.

In order to achieve the above object, the utility model is achieved through the following technical solutions:

A signal transmission line unit, which includes a pair of core wires, a ground wire and two layers of Mylar aluminum foil. The other side of the mylar is an insulating surface, and the ground wire is passed between two layers of aluminum foil mylar. The conductive surfaces of the two layers of aluminum foil mylar are both facing the ground wire, and the conductive surfaces of the two layers of aluminum foil mylar are respectively in electrical contact with the ground wire. .

The two core wires are arranged in parallel, and the periphery of the two core wires is longitudinally covered with a fixed belt made of foamed polypropylene, and the fixed belt is between the inner aluminum foil Mylar and the core wire.

The two layers of aluminum foil Mylar are respectively wound on the periphery of the fixing belt along the length direction of the core wire, and the winding directions of the two layers of aluminum foil Mylar are opposite.

The core wire is composed of a conductor and an insulating layer made of high-density polypropylene covering the periphery of the conductor.

The conductive surface of the aluminum foil mylar is made of aluminum material.

The outer periphery of the aluminum foil Mylar located on the outer layer is covered with a layer of hot-melt Mylar longitudinally.

The outer periphery of the hot-melt mylar is longitudinally covered with a layer of metal shielding layer, and the metal shielding layer is a wire winding or a wire braided net.

Beneficial effects of the utility model: the utility model includes a pair of core wires, a ground wire and two layers of aluminum foil Mylar, the periphery of the core wire is covered with two layers of aluminum foil Mylar along the length direction of the core wire, and one side of the aluminum foil Mylar is conductive The other side of the aluminum foil mylar is the insulating surface, and the ground wire is passed between two layers of aluminum foil mylar. Electrical contact, it reduces the capacitance of the signal transmission line unit, increases the inductance of the signal transmission line unit, forms a high impedance, and makes the signal transmission line unit have good high-frequency performance.

Description of drawings:

Accompanying drawing 1 is the structural representation of existing signal transmission line unit;

Accompanying drawing 2 is the structural representation of the utility model.

Detailed ways:

The signal transmission line unit is shown in Figure 2, which includes a pair of core wires 1, a ground wire 2 and two layers of aluminum foil Mylar 3. The insulating layer 1b is made of PP material. The high-density insulating layer 1b makes the core wire 1 not easy to deform and ensures that the core wire 1 has a stable impedance.

The two core wires 1 are arranged in parallel, and the periphery of the two core wires 1 is longitudinally covered with a fixed belt 4 made of polypropylene PP foamed. between 1. The fixing belt 4 fixes the two core wires 1 in parallel, which is convenient for the subsequent operation of the aluminum foil-clad Mylar 3 process.

The periphery of the core wire 1 is covered with two layers of aluminum foil Mylar 3 along the length direction of the core wire 1. One side of the aluminum foil Mylar 3 is a conductive surface, and the conductive surface of the aluminum foil Mylar 3 is a surface made of aluminum material; The other side of 3 is an insulating surface. The ground wire 2 is set between two layers of aluminum foil Mylar 3. The conductive surfaces of the two layers of aluminum foil Mylar 3 are all facing the ground wire 2. Wire 2 is in electrical contact. The structure of the two layers of aluminum foil Mylar 3 and the ground wire 2 sandwiched between the two layers of aluminum foil has the following functions: 1. Reduce the capacitance of the signal transmission line unit; 2. Increase the inductance of the signal transmission line unit to form a high impedance.

The two layers of aluminum foil Mylar 3 are respectively wound around the periphery of the fixing belt 4 along the length direction of the core wire 1 , and the winding directions of the two layers of aluminum foil Mylar 3 are opposite. For example, when the inner layer of aluminum foil Mylar 3 is wrapped in a clockwise direction, the outer layer of aluminum foil Mylar 3 is wrapped in a counterclockwise direction, and the wrapping directions of the two layers of aluminum foil Mylar 3 are opposite, so that the inner layer can be The gap left by the aluminum foil Mylar 3 is tightly wrapped, so that the ground wire 2 has a good contact with the guide surface of the aluminum foil Mylar 3, and the ground wire 2 is tightly wrapped, so that the signal transmission line unit has a good Electromagnetic shielding EMI effect.

The periphery of the aluminum foil Mylar 3 located on the outer layer is longitudinally covered with a layer of hot-melt Mylar 5, the hot-melt Mylar 5 is heat-fused on the outer layer of the aluminum foil Mylar 3, and the hot-melt Mylar 5 wraps the aluminum foil Mylar 3 The package is tight to prevent the aluminum foil Mylar 3 from being damaged or folded, which may cause a short circuit.

The outer periphery of the hot-melt mylar 5 is longitudinally covered with a layer of metal shielding layer 6, and the metal shielding layer 6 is a wire winding or a wire braided mesh. The function of the metal shielding layer 6 is to enhance the electromagnetic shielding EMI protection performance of the signal transmission line unit.

The above is only a preferred embodiment of the utility model, so all equivalent changes or modifications made according to the structure, features and principles described in the utility model patent application scope are all included in the utility model patent application scope .

Claims (7)

1. A signal transmission line unit, which includes a pair of core wires (1) and a ground wire (2), characterized in that: the signal transmission line unit also includes two layers of aluminum foil Mylar (3), the core wire (1) The periphery of the core wire (1) is covered with two layers of aluminum foil Mylar (3), one side of the aluminum foil Mylar (3) is a conductive surface, the other side of the aluminum foil Mylar (3) is an insulating surface, and the ground wire (2 ) between two layers of aluminum foil mylar (3), the conductive surfaces of the two layers of aluminum foil mylar (3) are all facing the ground wire (2), and the conductive surfaces of the two layers of aluminum foil mylar (3) are respectively connected to the ground wire ( 2) Electrical contact. 2. A signal transmission line unit according to claim 1, characterized in that: the two core wires (1) are arranged in parallel, and the periphery of the two core wires (1) is longitudinally covered with a layer of polypropylene hair. The fixing band (4) made by soaking, the fixing band (4) is between the aluminum foil mylar (3) and the core wire (1) of the inner layer. 3. A signal transmission line unit according to claim 2, characterized in that: the two layers of aluminum foil Mylar (3) are respectively wound around the periphery of the fixing belt (4) along the length direction of the core wire (1), And the winding directions of the two layers of aluminum foil Mylar (3) are opposite. 4. A signal transmission line unit according to any one of claims 1 to 3, characterized in that the core wire (1) is made of a conductor (1a) and a high-density wire wrapped around the conductor (1a) The insulation layer (1b) is made of polypropylene material. 5. A signal transmission line unit according to claim 4, characterized in that: the conductive surface of the aluminum foil Mylar (3) is made of aluminum material. 6. A signal transmission line unit according to claim 4, characterized in that: the periphery of the outer aluminum foil Mylar (3) is longitudinally covered with a layer of hot-melt Mylar (5). 7. A signal transmission line unit according to claim 6, characterized in that: the outer periphery of the hot-melt mylar (5) is longitudinally covered with a layer of metal shielding layer (6), and the metal shielding layer (6) is made of metal Wire wound or wire braided mesh.

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