KR20220111548A - Ethernet Cable For Vehicle - Google Patents

Abstract

The present invention relates to an Ethernet cable for a vehicle. More specifically, the Ethernet cable for a cable of the present invention enables high-capacity data communication and high-speed transmission required in network systems for a vehicle based on a low voltage differential signal (LVDS), minimizes the overall outer diameter and weight, and has excellent vibration resistance and electrical characteristics.

Description

Ethernet Cable For Vehicle

The present invention relates to an Ethernet cable for a vehicle. More specifically, the present invention enables large-capacity data communication and high-speed transmission required in a vehicle network system based on a low voltage differential signal (LVDS), minimizes the overall outer diameter and weight, and reduces vibration resistance and It relates to an Ethernet cable for vehicles with excellent electrical characteristics.

Recently, as information and communication technology (ICT) technology is converged into vehicles, the vehicle network system provides a connected car function, V2X communication, autonomous driving, remote control service, etc. as well as a communication function between in-vehicle devices. It is developing into an In-Vehicle infotainment (IVI) system.

Accordingly, the demand for large-capacity data processing and high-speed transmission in the vehicle network system is further increasing. In this regard, a low voltage differential signal capable of reducing power consumption and capable of high-speed transmission by using a low voltage; LVDS) system method may be applied.

LVDS refers to a general interface standard for high-speed data transmission. In particular, it has high transmission characteristics as a transmission medium for data transmission of various electronic equipment such as lidar sensors, semiconductors, displays, and camera modules in vehicles. , an Ethernet cable that supports a relatively wide bandwidth, has excellent flexibility and heat resistance, and has a relatively low manufacturing cost, is mainly used.

6 shows a cross-sectional view of an example of a conventionally introduced vehicle Ethernet cable. As shown in FIG. 6 , the conventional vehicle Ethernet cable 100 ′ includes a plurality of wires 21 and an insulator 23 surrounding the entire wire, and a pair of conductor wires 20 twisted with each other at a large pitch pitch. , and an outer jacket 40 surrounding the pair of conductor wires 20 as a whole.

Here, in the conventional vehicle Ethernet cable 100 ′, a plurality of Ethernet cables 100 ′ must be installed in proportion to the type of transmission signal, and the preparation for noise caused by the mutual influence between the cables was not sufficient. In addition, the conventional vehicle Ethernet cable 100 ′ lacks preparation for vibration and shock, so it was not possible to guarantee sufficient durability as a vehicle cable.

In addition, when Ethernet cables such as general UTP cables and STP cables are applied to a vehicle, these cables are not designed in consideration of electrical characteristics according to the LVDS standard, so there is a problem that may cause adverse effects such as malfunction or transmission loss.

In addition, when an Ethernet cable, such as a general UTP cable or STP cable, is applied to a vehicle, it has a structure including four pairs in which eight conductor wires are twisted at a parallel pitch by two, where among the eight conductor wires, Since the four conductor wires are usually used as a ground or a spare function, there is a problem in that unnecessary resources are wasted and the cost is increased.

In order to solve these problems, it enables large-capacity data communication and high-speed transmission required in a vehicle network system based on Low Voltage Differential Signal (LVDS), minimizes the overall weight, and reduces durability and attenuation of vibration or There is a great demand for an Ethernet cable for vehicles with excellent electrical characteristics such as near-end crosstalk.

The invention enables large-capacity data communication and high-speed transmission required in a vehicle network system based on Low Voltage Differential Signal (LVDS), minimizes the overall outer diameter and weight, and has excellent vibration resistance and electrical characteristics. Providing an Ethernet cable is a challenge to be solved.

In order to solve the above problems, the present invention is a filler member; four conductor wires disposed around the filler member and comprising a plurality of wires having a total cross-sectional area of 0.15 to 0.17 mm ² and an insulator surrounding the plurality of wires; a shielding layer surrounding the four conductor wires; and an outer jacket surrounding the shielding layer, wherein the four conductor wires are combined at a combined pitch of 26 to 34 millimeters (mm), and a pair of each of the four conductor wires consists of two each. Provided is an Ethernet cable for a vehicle characterized in that it is possible to transmit different low voltage differential signaling (LVDS) signals.

Here, the combined pitch of the four conductor wires may be preferably 29 to 31 millimeters (mm).

And, with respect to the 50 MHz test signal of the cable, the attenuation per unit length (m) may satisfy 0.25 dB or less.

In addition, with respect to the 50 MHz test signal of the cable, the near-end cross-talk in the 100-meter (m) transmission section may satisfy 50 dB or more.

Here, the average diameter (mm) of the plurality of wires constituting the four conductor wires may be 0.16 to 0.18 millimeters (mm).

In this case, each of the four conductor wires may be composed of seven wires, and the seven wires may be arranged such that one wire is in the center and six wires are circumscribed around the seven wires.

In addition, the four conductor wires may have a characteristic impedance of 90 to 110 ohms (Ω) with respect to a 50 MHz test signal because the thickness of the insulator is 0.3 to 0.6 millimeters (mm).

In addition, the filler member is made of at least one of polyethylene (PE), fluorinated ethylene propylene (FEP) and polyethylene terephthalate (PET), and has an outer diameter of 0.5 to 0.6 millimeters (mm). ) can be

In addition, the outer diameter of each of the four conductor wires may be 1.3 to 1.7 millimeters (mm).

Here, the cable outer diameter may be 4.5 to 6.0 millimeters (mm).

In addition, it further includes a shielding layer surrounding the four conductor wires, the shielding layer may include an aluminum mylar (Al-mylar) tape layer.

In this case, the shielding layer may include a braided layer including at least one of tin-plated copper and carbon fibers surrounding the aluminum mylar (Al-mylar) tape layer.

In addition, the aluminum mylar (Al-mylar) tape layer constituting the shielding layer may be transversely wound in a direction different from the union direction of the four conductor wires.

In this case, it may further include an outer jacket surrounding the shielding layer.

According to the vehicle Ethernet cable according to the present invention, by controlling the combined pitch of the four conductor wires to minimize the signal and power loss based on the low voltage differential signal (Low Voltage Differential Signal; LVDS) high-capacity data communication and high-speed required in the vehicle network system transmission becomes possible.

In addition, according to the Ethernet cable for a vehicle according to the present invention, it is possible to reduce the cable manufacturing cost by controlling the cross-sectional area (mm ² ) of a plurality of wires constituting each of the four conductor wires, thereby minimizing the amount of conductor used, and the total outer diameter and By minimizing the weight, it is possible to improve the energy efficiency and interior space efficiency of the vehicle.

In addition, according to the Ethernet cable for a vehicle according to the present invention, by arranging a pillar member in the center, resistance to vehicle vibration is improved and roundness is maintained, so that overall cable durability can be improved.

In addition, according to the Ethernet cable for a vehicle according to the present invention, by configuring the union direction of the four conductor wires and the transverse winding direction of the shielding layer differently from each other, the return loss among electrical characteristics is improved, so that the impedance matching of the Ethernet cable is smooth even in a high-speed transmission environment can be implemented.

1 shows a multi-stage stripped perspective view of an Ethernet cable for a vehicle according to the present invention.
2 shows a cross-sectional view of an Ethernet cable for a vehicle according to the present invention.
3 is a graph showing the measurement result of the attenuation amount and the near-end crosstalk for each wire diameter according to the combined pitch of four conductor wires constituting the Ethernet cable for a vehicle according to the present invention.
4 is a graph showing a measurement of the return loss when the aluminum mylar tape layer of the Ethernet cable for a vehicle according to the present invention is transversely wound in a direction different from the union direction of four conductor wires.
5 is a graph showing a measurement of the return loss when the aluminum mylar tape layer of the Ethernet cable for a vehicle according to the present invention is transversely wound in the same direction as the union direction of four conductor wires.
6 shows a cross-sectional view of a conventional vehicle Ethernet cable.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. However, the present invention is not limited to the embodiments described herein and may be embodied in other forms. Rather, the embodiments introduced herein are provided so that the disclosed subject matter may be thorough and complete, and the spirit of the invention may be sufficiently conveyed to those skilled in the art. Like reference numbers refer to like elements throughout.

Recently, according to the spread of In-Vehicle infotainment (IVI) in vehicle networks, from satellite navigation functions to recently connected car functions, V2X communication, autonomous driving, remote control services, etc. this is being provided.

In order to implement the infotainment function of the vehicle, sensors, radars or cameras installed inside the vehicle and communication cables for vehicles installed inside the vehicle to connect them with a central processing unit (ECU, etc.) are also increasing significantly. Such a vehicle cable requires the application of a cable capable of high-speed communication since the size of transmission data is larger than that of the prior art.

In an environment that requires high-speed data transmission in the vehicle, the Low Voltage Differential Signals (LVDS) method can be applied. do. In particular, since a relatively low voltage of DC 12V or DC 24V is used as the main power supply voltage for a vehicle, it has technical and economic advantages in constructing a vehicle network system when LVDS is applied.

On the other hand, low-voltage differential signal (LVDS) is an interface standard for high-speed data transmission. The Ethernet cable used as the transmission medium of LVDS must maintain sufficient voltage and waveform to transmit data, so the signal attenuation must be small, and other adjacent Ethernet cables Alternatively, it should be configured to minimize electromagnetic interference (EMI) between the inner conductor wires.

In addition, since the amount of Ethernet cables for vehicles connected to various electronic components inside the vehicle is increased, it is necessary to reduce the weight and secure sufficient durability as a vehicle cable to minimize the increase in the load on the vehicle. In addition, it is required to minimize mutual influence such as noise between adjacent cables.

Therefore, the present invention is configured to smoothly perform large-capacity data communication and high-speed transmission required in a vehicle network system based on Low Voltage Differential Signal (LVDS), and at the same time minimize the overall outer diameter and weight, and provide sufficient durability and excellent shielding performance. An object of the present invention is to provide an Ethernet cable for vehicles that secures the

Figure 1 shows a stripped perspective view of the vehicle Ethernet cable 100 according to the present invention, Figure 2 is a cross-sectional view of the vehicle Ethernet cable 100 according to the present invention shown in FIG.

1 and 2, the vehicle Ethernet cable 100 according to the present invention includes a pillar member 10; Four conductor wires disposed around the filler member 10 and comprising a plurality of wires 21 having a total cross-sectional area of 0.15 to 0.17 mm ² and an insulator 23 surrounding the plurality of wires 21 . (20); a shielding layer 30 surrounding the four conductor wires; and an outer jacket 40 surrounding the shielding layer, wherein the four conductor wires 20 are combined at a combined pitch of 26 to 34 millimeters (mm), and the four conductor wires 20 are 2 Each pair of pairs is characterized in that it is possible to transmit different low voltage differential signaling (LVDS) signals, respectively.

In the vehicle Ethernet cable 100 according to the present invention, one pillar member 10 is disposed at the center, and the pillar member 10 is an arrangement of four conductor wires 20 disposed around the pillar member 10 . to maintain the roundness of the cable, and serves to protect the four conductor wires 20 against mechanical vibration or other external force when the Ethernet cable 100 is installed or the vehicle.

The filler member 10 may include various polymer resins, for example, polyethylene (PE), fluorinated ethylene propylene (FEP), polyethylene terephthalate (PET), polyvinyl chloride (PVC). ), may be made of a resin such as polypropylene (PP), preferably polyethylene (PE), fluorinated ethylene propylene (FEP), and polyethylene terephthalate (polyethylene terephthalate; PET) at least one of can be done Here, when the filler member 10 is made of a polyethylene terephthalate (PET) material, it has a relatively high hardness, so that the elongation of the filler member 10 during cable manufacturing can be minimized or prevented. .

The outer diameter of the filler member 10 may be 0.5 to 0.6 millimeters (mm), and when the outer diameter of the filler member 10 is less than 0.5 millimeters (mm), the filler member 10 is stretched by an external force or On the other hand, when the outer diameter of the filler member 10 exceeds 0.6 millimeters (mm), the outer diameter of the filler member 10 becomes excessively large, so that the overall outer diameter and weight of the cable are unnecessarily increased. there is a problem.

The vehicle Ethernet cable 100 according to the present invention is configured to include four conductor wires 20 responsible for a signal transmission function in the vehicle, and the four conductor wires 20 are formed with the pillar member 10 as the center. The outer diameter of the cable can be minimized by disposing it to be circumscribed.

Here, each of the four conductor lines 20 may be in charge of transmission of a different low voltage differential signaling (LVDS) in a pair of two conductor lines, respectively. Specifically, the four conductor wires 20 are a pair of each of the two conductor wires 20a, 20b and 20c, 20d arranged opposite to the pillar member 10 disposed in the center. (pair) may be connected to each of the connector terminals connected to the vehicle electrical component to perform a communication function.

In this case, since the vehicle Ethernet cable 100 of the present invention can use all four conductor wires 20 for data transmission, like a general UTP cable, a conductor wire having a ground or a spare function is omitted. , it prevents unnecessary expansion of the outer diameter of the cable, and enables more large-capacity data transmission than when using a conventional vehicle Ethernet cable including a single conductor wire pair and reduces the number of cables installed inside the vehicle. It has the advantage of convenient maintenance such as cleaning.

The four conductor wires 20 may be formed of a stranded conductor including a plurality of wires 21 having a total cross-sectional area (mm ² ) of 0.15 to 0.17 mm ² . Here, the sum (mm ² ) of the cross-sectional area of the plurality of wires 21 is precisely adjusted to satisfy the attenuation amount per unit length (m) of 0.25 dB or less for the 50 MHz test signal of the Ethernet cable 100 became

Here, the attenuation (Attenuation) is a value that measures how much is lost and weakened when the magnitude of the signal flowing along the cable is transmitted over a certain distance. It can be understood that the ability to transmit is excellent.

And, as the sum total (mm ² ) of the cross-sectional area of the plurality of wires 21 constituting each of the four conductor wires 20 increases, the resistance of the signal and power flowing inside the conductor wire 20 is reduced, so that the attenuation characteristic is improved. improved characteristics.

When the total cross-sectional area (mm ² ) of the plurality of wires 21 is less than 0.15 mm ² , the attenuation characteristic of the cable is greatly reduced and the total cross-sectional area (mm ² ) of the plurality of wires 21 is greater than 0.17 mm ² , Although the attenuation characteristics of the cable can be improved, there are problems in that the content of the conductor in the cable is excessively increased, so that the manufacturing cost is high, and the weight and the outer diameter of the cable are increased.

Preferably, each of the four conductor wires 20 may be composed of seven wires 21, and the seven wires 21 are arranged such that one wire is in the center and six wires are circumscribed around them. can In this configuration, the average diameter (mm) of each of the seven wires 21 constituting each of the four conductor wires 20 is 0.16 to 0.18 millimeters (mm), so that the The sum of the cross-sectional areas may be configured to maintain a range of 0.15 to 0.17 mm ² .

Each of the four conductor wires 20 is a stranded conductor in which a plurality of strands 21 are combined at a constant pitch, and when the stranded wire is configured in this way, the bending characteristics are excellent, so that it is easy to install in a complex electric space in a vehicle and has excellent durability. have characteristics.

The plurality of wires 21 constituting each of the four conductor wires 20 may be made of a metal material such as copper, aluminum, silver, or the like, or an alloy thereof, having low resistance and good conductivity.

The insulator 23 may be formed by extrusion of an insulating composition including a polymer resin having electrical insulating properties as a base resin, and the polymer resin is not particularly limited as long as it can implement electrical insulating properties, but for example, , may be made of a material such as polypropylene (PP).

Meanwhile, in order to stably transmit a high-frequency band signal using the Ethernet cable 100 , it is necessary to adjust the characteristic impedance according to the input/output impedance of the device connected to the Ethernet cable. The adjustment of such characteristic impedance can be achieved, for example, by adjusting the thickness of the insulator 23, the dielectric constant of the material of the insulator 23, the dielectric constant of the material of the filler member 10, etc. In particular, the present inventors 23), it was possible to satisfy the condition range of 90 to 110 ohms (Ω) of the characteristic impedance required for the vehicle Ethernet cable 100 of the present invention.

Specifically, when the outer diameter of the conductor wire 20 increases as the thickness of the insulator 23 increases, the capacitance of the cable sequentially decreases, the attenuation decreases, and the characteristic impedance value tends to increase, whereas the As the thickness of the insulator 23 decreases, when the outer diameter of the conductor wire 20 decreases, the capacitance of the cable tends to increase, the attenuation increases, and the characteristic impedance value tends to decrease.

Accordingly, when the insulator 23 is formed to have a thickness of 0.3 to 0.6 millimeters (mm), and the outer diameter of the conductor wire 20 according to the thickness of the insulator 23 is 1.3 to 1.7 millimeters (mm), the vehicle Ethernet It was experimentally confirmed that the characteristic impedance for the 50 MHz test signal of the cable 100 can be configured to satisfy 90 to 110 ohms (Ω).

When the combined pitch of the four conductor wires 20 is less than 26 mm, the length of the entire conductor wire 20 is increased due to the short combined pitch, which is contrary to weight reduction, and the combined pitch of the four conductor wires 20 is 34 mm In the case of excess, it was confirmed that the combined pitch is difficult to be maintained due to the restoring force of the cable itself, and in particular, the crosstalk attenuation effect between the four conductor wires 20 may be reduced.

Accordingly, the vehicle Ethernet cable 100 according to the present invention is characterized in that the four conductor wires 20 are combined with a combined pitch of 26 to 34 millimeters (mm), preferably 29 to 31 millimeters (mm). do it with As such, when the four conductor wires 20 are combined in the above-described pitch range, the outer diameter of the four conductive wires 20 combined may be 3.4 to 3.8 millimeters (mm).

The shielding layer 30 is a component provided to cover the entirety of the four conductor wires 20 , and the shielding layer 30 includes electromagnetic waves emitted to the outside from the four conductor wires 20 and viewed from the outside. The Ethernet cable 100 according to the present invention reflects or absorbs electromagnetic waves that want to penetrate into the interior and blocks them.

The shielding layer 30 is, for example, an aluminum mylar tape layer 31 comprising one or more aluminum mylar tapes with an aluminum foil attached to a polyester film and/or tinned copper and carbon fibers ( It may include a braided layer 33 configured to include at least one or more of (including metal-plated carbon fibers). When the shielding layer 30 includes both the aluminum mylar tape layer 31 and the braided layer 33 , the aluminum mylar tape layer 31 surrounds the four conductor wires 20 . It may be horizontally wound, and the braided layer 33 may be disposed to surround the aluminum mylar tape layer 31 .

Here, the thickness of the aluminum mylar tape layer 31 constituting the shielding layer 30 may be about 0.017 to 0.033 millimeters (mm), and the thickness of the braided layer 33 is 0.08 to 0.12 millimeters ( mm) can be configured. When the thickness of the aluminum mylar tape layer 31 and/or the braided layer 33 constituting the shielding layer 30 is formed within the above range, it is possible to appropriately block crosstalk between adjacent Ethernet cables. At the same time, the increase in the outer diameter of the Ethernet cable can be minimized.

In addition, one or more aluminum mylar tapes constituting the aluminum mylar tape layer 31 are formed around the four conductor wires 20 in a direction in which the four conductor wires 20 are combined with each other. It is provided so as to cross in a different direction, and in this case, the electrical characteristics of the vehicle Ethernet cable 100 of the present invention may be satisfied, and a description thereof will be described later.

The outer jacket 40 is disposed to surround the shielding layer 30 and serves to protect the four conductor wires 20 from external pressure or impact.

The outer jacket 40 can be composed of various polymer resin materials such as polypropylene, polyvinyl chloride, polyethylene, etc., and preferably includes a polypropylene resin with excellent heat resistance as a base resin. It can be made up by extrusions of the composition.

The thickness of the outer jacket 40 may be selected within the range of 0.48 to 0.68 millimeters (mm), and when the thickness of the outer jacket 40 is less than 0.48 mm, the cable is disconnected or damaged by external friction or bending. On the other hand, if the thickness exceeds 0.68 mm, there is a problem in that the flexibility of the cable is lowered and the overall outer diameter of the cable is increased. And, the outer diameter of the Ethernet cable of the present invention by the thickness of the outer jacket 40 may be 4.5 to 6.0 millimeters (mm).

3 is a graph showing an attenuation amount and near-end crosstalk (NEXT) for each wire diameter according to the combined pitch of the four conductor wires 20 constituting the vehicle Ethernet cable 100 according to the present invention.

As described above, in the vehicle Ethernet cable 100 according to the present invention, for stable long-distance communication based on a low voltage differential signal (LVDS), the vehicle Ethernet cable 100 is a unit for a 50 MHz test signal. Attenuation per length (m) must satisfy 0.25dB or less.

In the present specification, the attenuation amount of the vehicle Ethernet cable according to the present invention was measured with reference to TIA-EIA-644-A and the Open Alliance, a vehicle Ethernet system standard defined by the American Electronics Industry Association, and the actual measurement of the attenuation amount according to the measurement method Although the value is measured with a negative sign, the attenuation value measured in the present invention is indicated with a positive sign as the standard indicates a positive sign for the same value.

Here, the attenuation amount of the cable may implement the attenuation characteristics required for the cable by adjusting the cross-sectional area or diameter of a plurality of wires inside the conductor wire 20 .

The vehicle Ethernet cable 100 of the present invention, respectively, as shown in Table 1 below, according to the average diameter of the seven wires 21 constituting each of the four conductor wires 20, Comparative Example 1, Example 1 and Comparative Example 1 It was manufactured as in Example 2, and the attenuation amount (Attenuation) per 100 m length of each cable according to the combined pitch of the four conductor wires 20 was measured and shown in FIG. 3 .

Comparative Example 1
Example 1

Comparative Example 2
number of wires

7
7
7
Average wire diameter (mm)

0.16
0.17
0.18
Total wire cross-sectional area (mm ² )

about 0.141
about 0.159
about 0.178

As shown in FIG. 3 , in Comparative Example 1, the average diameter of the seven wires 21 constituting each of the four conductor wires 20 is relatively small, 0.16 mm, so that the conductor resistance inside the conductor wire 20 is relatively small. As this increased, the range of pitched pitch to achieve attenuation of 25dB or less per 100m of cable was formed too large, making it impossible to manufacture a cable composed of normally bundled conductor wires. In Example 1 and Comparative Example 2, it was confirmed that the minimum combined pitch for achieving an attenuation of 25 dB or less per 100 m of cable was about 17.8 mm and about 26.4 mm.

Since the conductor resistance decreases as the cross-sectional area or diameter of the wire constituting the conductor wire 20 increases, it is preferable to increase the wire diameter in terms of attenuation characteristics of the cable, but the vehicle Ethernet cable 100 of the present invention is a problem to reduce the overall outer diameter and weight of the cable by configuring to minimize the amount of conductor used as well as the attenuation characteristics of the cable. The average diameter (mm) of the wires of It was confirmed that it is preferable to configure in millimeters (mm).

On the other hand, as the combined pitch of the four conductor wires 20 completed on the basis of Example 1 or the length of the conductor according to it increases, the communication characteristic deteriorates due to near-end cross-talk. . Here, the near-end crosstalk (NEXT) refers to a phenomenon in which electrostatic coupling or electromagnetic coupling occurs between adjacent conductors, and a signal current of one conductor is induced in another conductor, thereby generating noise or signal interference.

In particular, in the vehicle Ethernet cable 100 of the present invention for transmitting an LVDS signal, electromagnetic interference (EMI) due to crosstalk between adjacent pairs inside the cable should be minimized along with attenuation characteristics, and the present inventors have With reference to the defined LVDS system standard TIA EIA 644 A and the vehicle Ethernet system standard, Open Alliance, for the 50 MHz test signal of the vehicle Ethernet cable 100, near-end cross-talk in the 100-meter (m) transmission section The combined pitch of the four conductor wires 20 was adjusted so that is 50 dB or more. Similarly, the actual measured value of the attenuation according to the measurement method is measured with a negative sign, but in the standard, the same value is expressed with a positive sign, so the attenuation value measured in the present invention is indicated with a positive sign.

As shown in FIG. 3, as a result of measuring the near-end crosstalk (NEXT) according to the joint pitch of the Ethernet cable manufactured based on Example 1, the range of the joint pitch for satisfying the near-end crosstalk of the cable is 50 dB or more. It was confirmed to be about 34.2 mm or less. Accordingly, when the combined pitch of the four conductor wires 20 is about 26 to 34 millimeters (mm), preferably, the combined pitch of the four conductor wires 20 is 29 to 31 millimeters (mm). It was confirmed that both the attenuation amount and the near-end crosstalk condition of the vehicle Ethernet cable 100 of the present invention can be satisfied.

That is, in the vehicle Ethernet cable 100 according to the present invention, the total (mm ² ) of the cross-sectional area of the seven wires constituting each of the four conductor wires 20 satisfies the range of 0.15 to 0.17 mm ² , and the four conductors When the wire 20 is configured with a combined pitch of 26 to 34 millimeters (mm), the use of conductors is minimized to reduce the cable manufacturing cost, while the overall outer diameter and weight of the cable are minimized to improve the energy efficiency and internal space efficiency of the vehicle. can be improved

4 is a return loss (RL) when the aluminum mylar tape layer 31 of the vehicle Ethernet cable 100 according to the present invention is transversely wound in a direction different from the union direction of the four conductor wires 20. 5 is a case in which the aluminum mylar tape layer 31 of the vehicle Ethernet cable 100 according to the present invention is transversely wound in the same direction as the union direction of the four conductor wires 20. The graph showing the measurement of return loss is shown.

Specifically, in the state in which the vehicle Ethernet cable 100 of the present invention is combined with the four conductor wires 20 in the S direction, the aluminum mylar tape layer 31 is transversely wound in the S direction and the Z direction, respectively, to form a transmission line. The return loss for each frequency (MHz) of the Ethernet cable 100 installed on the ethernet cable 100 was measured.

Here, the return loss refers to the degree of impedance matching between the cable and the connector. The return loss is the sum of the structural return loss, which is a loss caused by minute vibrations caused by the length of the cable, and the return loss of the signal that the input signal is generated from the connection part of the cable (connector, patch cord, etc.). The smaller the return loss value, the smaller the reflection, which means better impedance matching.

As shown in FIG. 4 , when the four conductor wires 20 are combined in the S direction and the aluminum mylar tape layer 31 is transversely wound in the Z direction, the four conductor wires (20) The unwinding phenomenon of the aluminum mylar tape layer 31 provided on the upper part was minimized and the internal structure was maintained in a stable state, so that the return loss value was measured to be relatively small.

In addition, when the aluminum mylar tape layer 31 is traversed in a direction different from the union direction of the four conductor wires 20, the return loss value measured in all test frequency (MHz) ranges is the return loss limit value ( It can be confirmed that it can have a sufficient margin than the Return Loss Limit (RL Limit).

Here, the return loss limit value is a value experimentally derived for the return loss of the Ethernet cable 100 for the vehicle. If the measured return loss value is greater than the RL Limit, the Ethernet cable connection part is damaged or the data transmission speed is This may decrease the overall performance of the LVDS system.

On the other hand, as shown in FIG. 5 , when the four conductor wires 20 are combined in the S direction and an aluminum mylar tape is applied transversely to the S direction, the cable is bent or bent. Various mechanical stresses such as stress and tensile force applied to the four conductor wires 20 were concentrated in a specific region of the conductor wire 20 along the transverse winding direction of the aluminum mylar tape layer 31, and communication characteristics were deteriorated, Specifically, as a result of the return loss measurement, the margin for the return loss limit in the frequency range of about 80 to 100 MHz is small or exceeds the limit value in the high frequency region, resulting in data loss or signal failure due to impedance mismatch. it is presumed to be

Therefore, in the vehicle Ethernet cable 100 according to the present invention, the return loss characteristic among the cable electrical characteristics is improved by configuring the union direction of the four conductor wires 20 and the transverse winding direction of the aluminum mylar tape layer 31 differently from each other. It was confirmed that it can be improved.

Although the present specification has been described with reference to preferred embodiments of the present invention, those skilled in the art can variously modify and change the present invention without departing from the spirit and scope of the present invention as set forth in the claims described below. will be able to carry out Therefore, if the modified implementation basically includes the elements of the claims of the present invention, all of them should be considered to be included in the technical scope of the present invention.

100: car Ethernet cable
10: filler member
20: conductor wire
30: shielding layer
40: outer jacket

Claims (14)

filler member;
four conductor wires disposed around the filler member and comprising a plurality of wires having a total cross-sectional area of 0.15 to 0.17 mm ² and an insulator surrounding the plurality of wires;
The four conductor wires are formed by being coupled at a combined pitch of 26 to 34 millimeters (mm), and a pair of two of the four conductor wires is configured to have a different low voltage differential signaling (LVDS) signal, respectively. Ethernet cable for vehicle, characterized in that the transmission is possible. The method of claim 1,
The combined pitch of the four conductor wires is preferably 29 to 31 millimeters (mm). According to claim 1,
For the 50 MHz test signal of the cable, the attenuation per unit length (m) is 0.25 dB or less. According to claim 1,
For the 50 MHz test signal of the cable, near-end cross-talk in a 100-meter (m) transmission section is 50 dB or more. According to claim 1,
The average diameter (mm) of the plurality of wires constituting the four conductor wires is 0.16 to 0.18 millimeters (mm). According to claim 1,
The four conductor wires are each composed of seven wires, and the seven wires are arranged such that one wire is in the center and six wires are circumscribed around the seven wires. 7. The method of claim 6,
The four conductor wires have a thickness of 0.3 to 0.6 millimeters (mm) and a characteristic impedance of 90 to 110 ohms (Ω) for a 50 MHz test signal. The method of claim 1,
The filler member is made of at least one of polyethylene (PE), fluorinated ethylene propylene (FEP), and polyethylene terephthalate (PET), and has an outer diameter of 0.5 to 0.6 millimeters (mm). Automotive Ethernet cable, characterized in that. 8. The method of claim 7,
The vehicle Ethernet cable, characterized in that the outer diameter of each of the four conductor wires is 1.3 to 1.7 millimeters (mm). According to claim 1,
The cable outer diameter is 4.5 to 6.0 millimeters (mm), characterized in that the vehicle Ethernet cable. According to claim 1,
A vehicle Ethernet cable, characterized in that it further comprises a shielding layer surrounding the four conductor wires, wherein the shielding layer comprises an aluminum mylar (Al-mylar) tape layer. 12. The method of claim 11,
The shielding layer comprises a braided layer comprising at least one of tin-plated copper and carbon fiber surrounding the aluminum mylar (Al-mylar) tape layer. 12. The method of claim 11,
The vehicle Ethernet cable, characterized in that the aluminum mylar (Al-mylar) tape layer is transversely wound in a direction different from the union direction of the four conductor wires. 12. The method of claim 11,
Ethernet cable for vehicle, characterized in that it further comprises; an outer jacket surrounding the shielding layer.

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