Communication cable and communication cable assembly

Abstract

The invention provides a communication cable and a communication cable assembly which can use a reversible plug that can be inserted even when the front and back of the plug are inverted relative to a socket and can extend a communication distance relative to a cable diameter. A communication cable (1) has two first differential pairs (2A, 2B) for transmitting high-speed differential signals, a second differential pair (3) for transmitting low-speed differential signals, a power supply line (4), a ground line (5), and an arrangement channel line (6) for detecting the orientation of the front and back of a plug, and does not have the first differential pair except for the two first differential pairs (2A, 2B).

Description

Technical Field

[0001] The invention relates to a communication cable and a communication cable assembly. Background Art

[0002] In recent years, transmission cables that can achieve cost reduction and improved transmission characteristics have been proposed (see, for example, Patent Document 1).

[0003] The USB (Universal Serial Bus) standard, one of the interface standards, has been formulated in various ways so far, and the maximum transmission speed is increasing. For example, it is 12Mbps in USB1.0 and USB1.1, 480Mbps in USB2.0, 5Gbps in USB3.0, 10Gbps in USB3.1, and 20Gbps in USB3.2. On the other hand, Type-A and Type-B are specified for connectors, but after USB3.1, Type-C, a reversible connector, is specified.

[0004] In addition, since the USB cable can perform various communications using one cable, the structure of the core wire is complicated and the number of core wires increases. For example, 4 cores are recommended in USB 2.0, 8 cores are recommended in USB 3.0, and 15 cores are recommended in USB Type-C.

[0005] The transmission cable described in Patent Document 1 is a transmission cable in accordance with the USB Type-C standard, and is a 17-core cable including 8 coaxial cables (for 10 Gbps transmission), 4 signal lines (1st SBU line, 2nd SBU line, CC line and Vconn line), 1 power line, 2 ground lines, and 1 pair of twisted pair lines.

[0006] Patent Document 1: Japanese Patent Application Publication No. 2017-10747

[0007] The existing transmission cables in accordance with the USB Type-C standard are used as charging cables for smartphones in many countries. Moreover, not limited to smartphones, there have been moves to adopt the USB Type-C standard as power cables or communication cables for PCs or other communication devices and image devices. This is not to unify the characteristics of the cables, but to unify the plugs (fitting parts) of the connectors and the sockets of the connected devices to improve convenience. On the other hand, in the USB Type-C standard, specifications are separately specified for cables and connectors. Due to the constraints of the substrate size of the connector in accordance with the USB Type-C standard, there are also constraints on the outer diameter of the cable (cable diameter). Therefore, it is impossible to increase the conductor cross-sectional area of ​​each core wire, and if the cable length is long, there is a problem of deterioration in communication quality. Summary of the invention

[0008] An object of the present invention is to provide a communication cable and a communication cable assembly that can use a reversible plug that can be inserted into a socket even if the front and back are reversed, and can extend the communication distance relative to the cable diameter.

[0009] [1] A communication cable comprising two first differential pairs for transmitting high-speed differential signals, a second differential pair for transmitting low-speed differential signals, a power line, a ground line, and a configuration channel line for detecting the orientation of the front and back of a plug, and having no first differential pair other than the two first differential pairs.

[0010] [2] The communication cable described in [1] above further comprises a circuit power line in the plug.

[0011] [3] In the communication cable described in [1] above, the signal line constituting the first differential pair includes a central conductor and an insulating layer covering the conductor, and the ratio of the conductor diameter of the conductor to the cable diameter is not less than 0.06 and not more than 0.07.

[0012] [4] In the communication cable described in [3] above, a ratio of a communicable distance of the high-speed differential signal to a diameter of the cable is 800 or more.

[0013] [5] In the communication cable described in [1] above, the number of core wires is not less than 9 and not more than 14.

[0014] [6] A communication cable assembly comprising the communication cable described in any one of [1] to [5] above and a pair of plugs electrically connected to both ends of the communication cable.

[0015] According to the invention of claims 1 and 5 , a reversible plug that can be inserted into the socket even if the front and back are reversed can be used, and the communication distance can be extended relative to the cable diameter.

[0016] According to the invention of claim 2, by using an IC chip (eMarker) as a circuit in the plug, high-speed charging of the device can be performed.

[0017] According to the invention of claims 3 and 4, if the cable diameter is kept the same as before, the communicable distance can be extended. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 (a) and (b) are plan views showing an example of a communication cable assembly according to the first embodiment of the present invention.

[0019] Figure 1(c) is a side view of the fitting portion and pins of the plug of the communication cable assembly according to the first embodiment of the present invention.

[0020] Figure 2 Yes means Figure 1 A cross-sectional view of one example of a communications cable is shown.

[0021] Figure 3 The figure shows a connector substrate corresponding to a cable compliant with the USB Type-C standard. (a) is a top view of the connector substrate as viewed from the front side, and (b) is a top view of the connector substrate as viewed from the back side.

[0022] Figure 4 An example of the connector substrate according to the first embodiment is shown. (a) is a plan view of the connector substrate as viewed from the front side, and (b) is a plan view of the connector substrate as viewed from the back side.

[0023] Figure 5 Indicates the first differential pair and Figure 4 The figures show the connection of the connector substrate, (a) is a top view of the connector substrate as viewed from the front side, and (b) is a top view of the connector substrate as viewed from the back side.

[0024] Figure 6 This is a cross-sectional view showing an example of a communication cable according to a second embodiment of the present invention.

[0025] Figure 7 This is a cross-sectional view showing an example of a communication cable according to a third embodiment of the present invention.

[0026] Figure 8 This is a cross-sectional view showing an example of a communication cable according to a fourth embodiment of the present invention.

[0027] Fig. 9 Indicates the first differential pair and Figure 4 The figures show the connection of the connector substrate, (a) is a top view of the connector substrate as viewed from the front side, and (b) is a top view of the connector substrate as viewed from the back side.

[0028] Fig.10 This is a cross-sectional view showing an example of a communication cable according to a fifth embodiment of the present invention.

[0029] Fig.11A This is a graph showing the attenuation characteristics when the cable length is 3 m.

[0030] Fig. 11B This is a diagram showing attenuation characteristics based on cable lengths corresponding to respective communicable distances.

[0031] Fig. 12A(a) and (b) are diagrams schematically showing examples of arrangement of core wires.

[0032] Fig. 12B (c) to (e) are diagrams schematically showing examples of arrangement of core wires.

[0033] Fig. 12C (f) to (k) in FIG. 1 are diagrams schematically showing examples of arrangement of core wires.

[0034] Fig.12D (l) to (q) in FIG. 1 are diagrams schematically showing examples of arrangement of core wires.

[0035] Description of reference numerals:

[0036] 1…communication cable; 2A, 2B…first differential pair; 2a~2d…signal line; 3…second differential pair; 3a, 3b…signal line; 4…power line; 5…ground line; 6…CC line; 7…sheath; 8…Vconn line; 9a~9d…coaxial line; 10…drain line; 11…shield; 11a…inner shield; 11b…outer shield; 12…shield; 12a…inner shield; 12b…outer shield; 13…filling rope; 21…conductor; 22…insulating layer; 31…conductor; 32…insulating layer; 41…conductor; 42…insulating layer; 51…conductor; 52…insulating layer; 61…conductor; 62…insulating layer; 81…conductor; 82…insulating layer; 91…center conductor; 92…inner insulating layer; 93… Outer conductor; 94…outer insulating layer; 100…communication cable assembly; 110A…first connector; 110B…second connector; 111A, 111B…shell; 112A, 112B…plug; 200A, 200B…connector substrate; 201…substrate; 201a…surface; 201b…back; 211…plug side surface terminal group; 211a~211l, 221a, 221b…terminal; 212…plug side back terminal group; 212a~212j, 222a, 222b…terminal; 231…cable side surface terminal group; 231a~231e…terminal; 231f…shielding terminal; 232…cable side back terminal group; 232a~232e…terminal; 232f…shielding terminal. DETAILED DESCRIPTION

[0037] Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. In the drawings, components having substantially the same functions are denoted by the same reference numerals and their repeated descriptions are omitted.

[0038] [First embodiment]

[0039] Figure 1(a) and (b) are top views showing an example of a communication cable assembly according to the first embodiment of the present invention. The communication cable assembly 100 comprises a communication cable 1 of a predetermined length within a communication distance, a first plug (hereinafter abbreviated as "first connector") 110A connected to the end of one side of the communication cable 1, and a second plug (hereinafter abbreviated as "second connector") 110B connected to the end of the other side of the communication cable 1. Figure 1 (c) is a side view of the fitting portion 112a and the pin 112b of the plug 112A or 112B of the communication cable assembly according to the first embodiment of the present invention.

[0040] The communication cable 1 is a communication cable that reduces the number of cores of the core structure of the cable in accordance with the USB Type-C standard to become a 9-core cable. That is, the cable in accordance with the USB Type-C standard has 4 pairs of high-frequency signal lines (SSTX1 line, SSRX1 line, SSTX2 line, SSRX2 line), but the communication cable 1 is a communication cable that limits the high-frequency signal lines to 2 pairs (for example, (SSTX1 line, SSRX1 line)).

[0041] In addition, the cable according to the USB Type-C standard has a signal line (SBU1 line, SBU2 line) for the alternate mode (HDMI (registered trademark) DisplayPort, etc.), but the present communication cable 1 has a structure without the alternate mode, in other words, a structure without signal lines (SBU1 line, SBU2 line) or a structure dedicated to USB signals. In addition, signal lines (SBU1 line, SBU2 line) may be added as needed.

[0042] Through the above structure, the number of core wires can be reduced, and the conductor diameter of the SSTX1 line and the SSRX1 line can be increased while keeping the cable diameter the same as before, so that the communicative distance can be extended. That is, the communicative distance relative to the cable diameter can be extended. In addition, by retaining the CC line in accordance with the USB Type-C standard, a reversible plug can be used that can be inserted even if the front and back (upside down) of the connector, that is, the socket in accordance with the USB Type-C standard, is reversed. In addition, because the number of core wires can be reduced, the core wires can be thickened, and as described later, advantages in the selection of materials for the resin layer and advantages in manufacturing can be obtained. In addition, in order to enjoy the convenience brought by the unification of connectors in accordance with the USB Type-C standard, as long as at least the shape and structure of the fitting part of the connector matches the shape and structure of the fitting part of the USB Type-C standard of the device to be connected, the shape and structure of the connector substrate or cable other than the fitting part of the connector may not be in accordance with the USB Type-C standard. That is, multiple ends of the communication cable are electrically connected to the plug. The plug includes a mating portion and pins having a shape and structure in accordance with the USB Type-C standard, but the number of pins in the plug is less than the number of pins in accordance with the USB Type-C standard. That is, the number of the multiple ends of the communication cable 1 electrically connected to the pins 112b is less than the number of pins in accordance with the USB Type-C standard.

[0043] The first connector 110A is connected to a socket provided in a computer, for example, and includes a resin housing 111A, a plug 112A provided to be exposed from the housing 111A, and a connector substrate 200 disposed in the housing 111A. The connector substrate 200A of the first connector 110A electrically connects the plug 112A to one end of the communication cable 1.

[0044] The second connector 110B is connected to a socket provided in a peripheral device, for example. Figure 1 As shown in (a) of FIG. 1 , the same connector as the first connector 110A is used. That is, the second connector 110B includes a housing 111A made of resin, a plug 112A provided to be exposed from the housing 111A, and a connector substrate 200A disposed in the housing 111A. The connector substrate 200A of the second connector 110B electrically connects the plug 112A to the other end of the communication cable 1.

[0045] In addition, in this embodiment, if Figure 1 As shown in (a) of FIG. 1 , the first connector 110A and the second connector 110B use the same connector, but Figure 1As shown in (b) in the figure, different connectors may be used. For example, the second connector 110B includes: a resin housing 111B having screws for preventing the connector from falling off; a plug 112B which is arranged to be exposed from the housing 111B; and a connector substrate 200A which is arranged in the housing 111B. In addition, in the present embodiment, the connector substrate 200A of the first connector 110A and the connector substrate 200A of the second connector 110B use the same substrate, but different substrates may be used.

[0046] (Structure of communication cable)

[0047] Figure 2 Yes means Figure 1 A cross-sectional view of an example of a communication cable 1 shown. The communication cable 1 is a 9-core cable having two first differential pairs 2A and 2B for transmitting high-speed differential signals (e.g., 5 Gbps to 20 Gbps), a second differential pair 3 for transmitting low-speed differential signals (e.g., 480 Mbps), a power line 4 (Vbus line), a ground line 5, and a configuration channel line (hereinafter referred to as "CC line") 6 for detecting the orientation of the front and back of the plug in accordance with the USB Type-C standard, and having no first differential pair other than the two first differential pairs 2A and 2B. That is, in the communication cable, there is no first actuating pair other than the two first differential pairs 2A and 2B. In addition, the communication cable 1 is not limited to a 9-core cable, but may be a cable with more than 10 cores and less than 14 cores. By having less than 14 cores, differentiation from the recommended number of cores (15 cores) in USB Type-C can be achieved. In addition, the CC line 6 may not be in accordance with the USB Type-C standard.

[0048] Among the signal wires 2a to 2d constituting the first differential pair 2A and 2B, the first differential pair is formed by two adjacent signal wires 2a and 2b, and the second differential pair is formed by another two adjacent signal wires 2c and 2d. A pair of signal wires 2a and 2b are twisted together with the drain wire 10 and covered by the shielding layer 11. Thus, a first twinax cable is formed. The other pair of signal wires 2a and 2b are also twisted together with the drain wire 10 and covered by the shielding layer 11, thereby forming a second twinax cable. Hereinafter, the communication cable 1 using a twinax cable in the first differential pair 2A and 2B is also referred to as a Twinax type communication cable. In addition, as a twinax cable, it can also be a non-twisted type. The drain wire 10 is, for example, a twisted wire formed by twisting a plurality of metal single strands. The signal wires 2a to 2d are an example of signal wires constituting the first differential pair.

[0049] The signal lines 2a to 2d include a conductor 21 and an insulating layer 22 covering the conductor 21. The conductor 21 is, for example, a stranded wire formed by twisting a plurality of metal strands. The insulating layer 22 is formed of a resin material (eg, cross-linked polyethylene). The conductor 21 is an example of a central conductor.

[0050] The shielding layer 11 comprises: an inner shielding layer 11a arranged inside and formed by winding a conductive tape (e.g., a tape formed by laminating aluminum and polyester); and an outer shielding layer 11b arranged outside the inner shielding layer 11a and formed by winding a resin tape (e.g., a polyester tape).

[0051] The second differential pair 3 is formed by twisting two signal lines 3a and 3b. The signal lines 3a and 3b include a conductor 31 and an insulating layer 32 covering the conductor 31. The conductor 31 is, for example, a stranded wire formed by twisting a plurality of metal strands. The insulating layer 32 is formed of a resin material (for example, cross-linked polyethylene).

[0052] The power supply line 4 includes a conductor 41 and an insulating layer 42 covering the conductor 41. The conductor 41 is, for example, a stranded wire formed by twisting a plurality of metal strands. The insulating layer 42 is formed of a resin material (for example, cross-linked polyethylene).

[0053] The ground wire 5 includes a conductor 51 and an insulating layer 52 covering the conductor 51. The conductor 51 is, for example, a stranded wire formed by twisting a plurality of metal strands. The insulating layer 52 is formed of a resin material (for example, cross-linked polyethylene). Alternatively, the ground wire 5 may be a bare wire without an insulating layer on the outer periphery.

[0054] The CC wire 6 includes a conductor 61 and an insulating layer 52 covering the conductor 61. The conductor 61 is, for example, a stranded wire formed by twisting a plurality of metal strands. The insulating layer 62 is formed of a resin material (for example, polyvinyl chloride).

[0055] The first differential pair 2A, 2B, the second differential pair 3, the power line 4, the ground line 5, and the CC line 6 are covered by the shield layer 12 together with the filling cord 13, and the outer side thereof is covered by the sheath 7. The sheath 7 is formed of a resin material (such as polyvinyl chloride) with a thickness of about 0.6 to 0.9 mm. The filling cord 13 is formed of a fibrous material (such as cotton, silk, etc.). The filling cord 13 is an example of an intervening object.

[0056] The shielding layer 12 comprises: an inner shielding layer 12a, which is arranged on the inner side and is formed by winding a conductive tape (for example, a tape formed by laminating aluminum and polyester); and an outer shielding layer 12b, which is arranged on the outer side of the inner shielding layer 12a and is formed by metal braiding (for example, tinned soft copper wire braiding).

[0057] (Structure of the connector substrate)

[0058] Figure 3The connector substrate 200B corresponding to the cable conforming to the USB Type-C standard is shown. (a) is a top view of the connector substrate 200B as viewed from the front side, and (b) is a top view of the connector substrate 200B as viewed from the back side. Figure 4 An example of the connector substrate 200A according to the present embodiment is shown, (a) is a top view of the connector substrate 200A as viewed from the front side, and (b) is a top view of the connector substrate 200A as viewed from the back side. Figure 3 and Figure 4 In the figure, A indicates the plug side, B indicates the cable side, and C indicates the width direction of the connector substrate.

[0059] (Structure of a connector board corresponding to a cable compliant with the USB Type-C standard)

[0060] like Figure 3 As shown, the connector substrate 200B corresponding to the cable compliant with the USB Type-C standard has a structure that can correspond to an 18-core cable, that is, the number of terminals (also called pads) is 18, and has a base material 201 formed of an insulating material.

[0061] like Figure 3 As shown in (a), a plug side surface terminal group 211 composed of terminals 211a~211l arranged on the plug side A, terminals 221a, 221b arranged between the plug side A and the cable side B, and a cable side surface terminal group 231 composed of terminals 231a~231i arranged on the cable side B are formed on the surface 201a of the substrate 201.

[0062] like Figure 3 As shown in (b), a plug side back terminal group 212 consisting of terminals 212a~212j arranged on the plug side A, terminals 222a, 222b arranged between the plug side A and the cable side B, and a cable side back terminal group 232 consisting of terminals 232a~232i arranged on the cable side B are formed on the back side 201b of the substrate 201.

[0063] The terminals 231a to 231i of the cable-side surface terminal group 231 are formed at a pitch of 0.9 to 1.0 mm, and the terminals 232a to 232i of the cable-side rear terminal group 232 are formed at a pitch of 0.9 to 1.0 mm. That is, the minimum pitch of the terminals in the width direction C of the connector substrate 200B is 0.9 mm.

[0064] (Structure of Connector Substrate of This Embodiment)

[0065] Although the connector substrate 200A of this embodiment complies with the USB Type-C standard, Figure 4As shown, it has a structure that can correspond to 9-core and 10-core cables, that is, the number of terminals (also called pads) is 10, and it has a base material 201 formed of an insulating material.

[0066] like Figure 4 As shown in (a) in FIG. 1 , a plug-side surface terminal group 211 composed of terminals 211a to 2111 provided on the plug side A, terminals 221a and 221b for a metal cover (not shown) provided between the plug side A and the cable side B, and a cable-side surface terminal group 231 composed of terminals 231a to 231f provided on the cable side B are formed on the surface 201a of the substrate 201. The terminal 231f of the cable-side surface terminal group 231 is a shielding terminal having a rectangular shape with the long side direction being the width direction C of the connector substrate 200A. The terminals 231a and 231b of the cable-side surface terminal group 231 are an example of a pair of surface terminals. The shielding terminal 231f is an example of a surface shielding terminal.

[0067] like Figure 4 As shown in (b) in FIG. 2 , a plug-side back terminal group 212 composed of terminals 212a to 212j provided on the plug side A, terminals 222a and 222b for a metal cover (not shown) provided between the plug side A and the cable side B and a cable-side back terminal group 232 composed of terminals 232a to 232f provided on the cable side B are formed on the back side 201b of the base 201. The terminal 232f in the cable-side back terminal group 232 is a shield terminal having a rectangular shape with the long side direction being the width direction C of the connector substrate 200A. The front surface 201a and the back surface 201b are examples of one side. The terminals 232a and 232b of the cable-side back terminal group 232 are examples of a pair of back terminals. The shield terminal 232f is an example of a back shield terminal.

[0068] The terminals 231a to 231e other than the shielding terminal 231f in the cable side surface terminal group 231 are formed at a pitch of 1.0 to 1.57 mm, and the terminals 232a to 232e other than the shielding terminal 232f in the cable side back terminal group 232 are formed at a pitch of 1.2 to 2.0 mm. That is, the minimum pitch of the terminals in the width direction C of the connector substrate 200A is 1.2 mm.

[0069] According to the connector substrate 200A of the present embodiment, the minimum spacing of the terminals in the width direction C can be enlarged to more than 1.3 times the minimum spacing of the terminals in the width direction C of the connector substrate 200B in accordance with the USB Type-C standard. In addition, because the number of cores of the cable is reduced, the number of pads of the connector substrate 200A can also be reduced, and the pad width can be expanded from 0.5 mm to 0.8 mm, for example, relative to a connector substrate of the same size and area as the connector substrate 200B in accordance with the USB Type-C standard. With the above structure, the connection operation can be performed with the naked eye. In addition, even without using a clamp (line straightening component) that arranges and holds the ends of the communication cable 1 to be connected, the connection operation of the communication cable 1 to the connector substrate 200A can be performed.

[0070] (Manufacturing method of communication cable assembly)

[0071] Next, an example of a method for manufacturing the communication cable assembly 100 according to the present embodiment will be described.

[0072] First, two first differential pairs 2A and 2B, a second differential pair 3, a power line 4, a ground line 5, a CC line 6, and a filling cord 13 are prepared. For the first differential pair 2A and 2B, two signal lines 2a and 2b or signal lines 2c and 2d and a drain line 10 are twisted, and a conductive tape is wound around the outer periphery to form an inner shield layer 11a, and a resin tape is wound around the outer periphery of the inner shield layer 11a to form an outer shield layer 11b. The second differential pair 3 is formed by twisting two signal lines 3a and 3b.

[0073] Next, the prepared two first differential pairs 2A, 2B, the second differential pair 3, the power line 4, the ground line 5, the CC line 6, and the filling rope 13 are twisted together, and a conductive tape is wound around their peripheries to form an inner shield layer 12a, and a metal braid is wound around the periphery of the inner shield layer 12a to form an outer shield layer 12b. Next, the sheath 7 is formed on the periphery of the shield layer 12 by extrusion molding using an extruder.

[0074] The communication cable 1 is manufactured as described above. Then, by cutting the communication cable 1 into a desired length and connecting the ends to the connector substrate 100A of the first connector 110A and the connector substrate 100A of the second connector 110B, the communication cable assembly 100 having the first connector 110A and the second connector 110B at both ends of the communication cable 1 is manufactured. In addition, the connection operation of the first differential pair 2A, 2B to the connector substrate 100A will be described later.

[0075] (Connection operation of the first differential pair)

[0076] Figure 5The diagram is used to explain the connection between the signal lines 2a to 2d of the first differential pair 2A and 2B and Figure 4 The figures show the state of the connector substrate 100A being connected, (a) is a plan view of the connector substrate 100A as viewed from the front side, and (b) is a plan view of the connector substrate 100A as viewed from the back side.

[0077] When the conductors 21 of the signal lines 2a and 2b of the communication cable 1 of the first embodiment are connected to Figure 3 When connecting the terminals 231a and 231b of the cable side surface terminal group 231 of the connector substrate 200B corresponding to the cable compliant with the USB Type-C standard shown in (a), the shielding layer 11 must be stripped off, and the insulating layer 22 of the signal lines 2a and 2b must be stripped off, and the exposed conductors 21 must be connected to the terminals 231a and 231b with a narrow pitch. Figure 4 When the terminals 231a and 231b of the cable side surface terminal group 231 of the connector substrate 200A shown in (a) are connected, the signal lines 2a and 2b can be easily connected because the spacing between the terminals 231a and 231b is wide. Figure 4 The same also applies to the back surface 201b of the connector substrate 200A shown in (b) of FIG. 1. The drain wire 10 is drawn out from the shield layer 11 and connected to a metal cover (not shown) of the plug 112A.

[0078] (Effects of the First Embodiment)

[0079] According to the communication cable assembly 100 of the first embodiment, the following effects are achieved.

[0080] (a) For the core wire structure of the cable conforming to the USB Type-C standard, the number of core wires can be reduced, the manufacturing cost can be reduced, and the weight can be reduced.

[0081] (b) When the outer diameters of the cables are the same, the outer diameter of the core wire can be thickened, thereby improving various properties (communication performance, bending resistance (referring to the property of not easily breaking the wire when repeatedly bent. The same applies below), mechanical strength). In addition, by thickening the conductor, the risk of breaking caused by the injection pressure during molding is reduced, thereby widening the range of choices for the molding method. In addition, when the outer diameters of the cables are the same, the core wires of the signal lines 2a, 2b, etc. can be thickened, thereby widening the range of choices for the material of the insulation layer. For example, the constituent material can be selected from expensive nylon resins such as polyamide to inexpensive polyolefin resins such as polyethylene, and the molding machine can be changed from a dedicated molding machine for low-pressure molding to a general-purpose molding machine for injection molding, thereby shortening the molding time.

[0082] (c) Since the communication distance of the high-speed differential signal can be extended relative to the cable diameter, the communication cable can be made lighter without shortening the communication distance when the cable diameter is reduced (e.g., 3.7 mm). In addition, since the conductor 21 of the first differential pair 2A, 2B can be thickened when the cable diameter is made the same as before (e.g., 6.8 mm), the communication distance can be extended.

[0083] (d) Since the CC wire 6 is provided, a reversible plug can be used which can be inserted into the socket even if it is turned upside down.

[0084] (e) Since the pitch between the terminals 231a and 231b and the pitch between the terminals 232a and 232b of the connector substrate 200A are wide, the signal lines 2a to 2d constituting the first differential pair 2A and 2B can be easily connected to the connector substrate 200A.

[0085] [Second embodiment]

[0086] Figure 6 This is a cross-sectional view showing an example of a communication cable according to the second embodiment of the present invention. In the communication cable 1 according to the first embodiment, the CC wire 6 is arranged between the power wire 4 and the ground wire 5, but the communication cable 1 according to this embodiment is formed by arranging the CC wire 6 at a position in contact with the shielding layer 11 covering the first differential pair 2B and the ground wire 5 and reducing the conductor diameter of the conductor 21 of the signal wires 2a to 2d to reduce the cable diameter. Since the communication cable assembly 100 according to the second embodiment is manufactured in the same manner as the first embodiment, its description is omitted.

[0087] According to the second embodiment, by appropriately selecting the outer diameters of the power line 4 , the ground line 5 , and the CC line 6 , the outer diameter of the cable can be made smaller than that of the first embodiment without shortening the communicable distance of the high-speed differential signal.

[0088] [Third Embodiment]

[0089] Figure 7 This is a cross-sectional view showing an example of a communication cable according to the third embodiment of the present invention. In the communication cable 1 of the first embodiment, it is a 9-core cable, but the communication cable 1 of this embodiment is a 10-core cable by adding a power line for the circuit in the plug (hereinafter referred to as "Vconn line") in accordance with the USB Type-C standard to the communication cable 1 of the first embodiment. The following description will focus on the differences from the first embodiment.

[0090] The communication cable 1 of the third embodiment is a 10-core cable having two first differential pairs 2A and 2B, a second differential pair 3, a power line 4, a ground line 5, and a CC line 6 in accordance with the USB Type-C standard, and further having a Vconn line 8, similarly to the first embodiment. In addition, the communication cable 1 is not limited to a 10-core cable, but may be a cable with 11 or more cores. In addition, the Vconn line 8 may not be in accordance with the USB Type-C standard.

[0091] The Vconn line 8 includes a conductor 81 and an insulating layer 82 covering the conductor 81. The conductor 81 is, for example, a stranded wire formed by twisting a plurality of metal strands. The insulating layer 82 is formed of a resin material (for example, polyvinyl chloride).

[0092] In the first embodiment, the CC line 6 is arranged between the power line 4 and the ground line 5, but in this embodiment, the CC line 6 is arranged side by side with the power line 4 and the ground line 5, and the CC line 6 is arranged on one side of them and the Vconn line 8 is arranged on the other side. The CC line 6 and the Vconn line 8 are connected to the IC chip (eMarker) built into the plug. The communication cable assembly 100 of the third embodiment is manufactured in the same manner as the first embodiment, so its description is omitted.

[0093] According to the third embodiment, the same effects as those of the first embodiment are achieved, and the CC line 6 and the Vconn line 8 are provided, so that the charger and the device can be connected via the communication cable 1 and the device can be charged at a high speed using power corresponding to the USB PD (Power Delivery) standard.

[0094] [Fourth embodiment]

[0095] Figure 8 This is a cross-sectional view showing an example of a communication cable according to the fourth embodiment of the present invention. In the communication cable 1 according to the first embodiment, the first differential pair of signal lines 2a and 2b constituting the two first differential pairs 2A and 2B and the second differential pair of signal lines 2c and 2d are shielded together by the shielding layer 11, respectively. However, the communication cable 1 according to this embodiment uses coaxial cables 9a to 9d as communication cables (also referred to as coaxial type communication cables) as signal lines constituting the two first differential pairs 2A and 2B. The following description will focus on the differences from the first embodiment.

[0096] Regarding the communication cable 1 of the fourth embodiment, the first differential pair 2A is composed of a first differential pair of a pair of coaxial lines 9a and 9b, and the first differential pair 2B is composed of a second differential pair of a pair of coaxial lines 9c and 9d. These coaxial lines 9a to 9d are arranged on the outer periphery, and the CC line 6 and the filling rope 14 are arranged in the center. The first differential pair 2A, 2B, the second differential pair 3, the power line 4, and the ground line 5 are covered with the shielding layer 12 together with the filling rope 13, and the outer side is covered with the sheath 7. The filling rope 14 is formed of a resin material (for example, polyethylene). The coaxial lines 9a to 9d are an example of a signal line constituting the first differential pair. The filling rope 14 is an example of an intervening object.

[0097] The coaxial lines 9a to 9d include a center conductor 91, an inner insulating layer 92 covering the center conductor 91, an outer conductor 93 formed outside the inner insulating layer 92, and an outer insulating layer 94 covering the outer conductor 93. The center conductor 91 is, for example, a stranded wire formed by twisting a plurality of metal strands. The inner insulating layer 92 is formed of a resin material (e.g., cross-linked polyethylene). The outer conductor 93 is, for example, formed of a metal braid. The outer insulating layer 94 is formed of a resin material (e.g., polyvinyl chloride). The center conductor 91 is an example of a center conductor.

[0098] (Manufacturing method of communication cable assembly)

[0099] Next, an example of a method for manufacturing the communication cable assembly 100 according to the fourth embodiment will be described.

[0100] First, prepare two first differential pairs 2A, 2B, a second differential pair 3, a power line 4, a ground line 5, a CC line 6, and filler cords 13, 14. Prepare four coaxial lines 9a to 9d constituting the first differential pairs 2A, 2B. The second differential pair 3 is formed by twisting two signal lines 3a, 3b.

[0101] Next, the prepared two first differential pairs 2A, 2B, the second differential pair 3, the power line 4, the ground line 5, the CC line 6, and the filling cords 13, 14 are twisted and a conductive tape is wound around their peripheries to form an inner shield layer 12a, and a metal braid is wound around the periphery of the inner shield layer 12a to form an outer shield layer 12b. Next, a sheath 7 is formed on the periphery of the shield layer 12 by extrusion molding using an extruder.

[0102] The communication cable 1 is manufactured as described above. Then, by cutting the communication cable 1 into a desired length and connecting the ends to the connector substrate 100A of the first connector 110A and the connector substrate 100A of the second connector 110B, the communication cable assembly 100 having the first connector 100A and the second connector 100B at both ends of the communication cable 1 is manufactured. In addition, the connection operation of the coaxial lines 9a to 9d constituting the first differential pair 2A, 2B to the connector substrate 100A is described later.

[0103] (Connection operation of the first differential pair)

[0104] Fig. 9 Indicates the first differential pair and Figure 4 The figures show the connection of the connector substrate, (a) is a top view of the connector substrate as viewed from the front side, and (b) is a top view of the connector substrate as viewed from the back side.

[0105] When the central conductors 91 of the coaxial wires 9a and 9b of the communication cable 1 of the fourth embodiment are connected to Figure 3 When connecting the terminals 231a and 231b of the cable side surface terminal group 231 of the connector substrate 200B corresponding to the cable compliant with the USB Type-C standard shown in (a), the outer insulating layer 94 must be stripped off, and the inner insulating layer 92 of the coaxial lines 9a and 9b must be stripped off, and the exposed center conductor 91 must be connected to the terminals 231a and 231b with a narrow spacing. In addition, the outer conductor 93 needs to be pulled out like a single wire and connected to the shield terminal (the metal cover of the plug 112A not shown in the figure). On the other hand, when connecting the center conductor 91 of the coaxial lines 9a and 9b to the Figure 4 When the terminals 231a and 231b of the cable side surface terminal group 231 of the connector substrate 200A shown in (a) are connected, the spacing between the terminals 231a and 231b is wide, so the coaxial lines 9a and 9b can be easily connected. In addition, even if the exposed outer conductor 93 is not pulled out like a single wire, the outer peripheral surface can be connected to the shield terminal 231f. Figure 4 The same also applies to the back surface 201b of the connector substrate 200A shown in (b) in FIG.

[0106] (Effects of the Fourth Embodiment)

[0107] According to the communication cable 1 of the fourth embodiment, the same effect as the first embodiment is achieved, and coaxial lines 9a~9d are used as signal lines constituting the first differential pair 2A, 2B. Therefore, the outer insulating layer 94 of the coaxial lines 9a~9d can be stripped off and the outer peripheral surface of the exposed outer conductor 93 can be connected to the shielding terminals 231f, 232f, thereby facilitating the connection operation of the coaxial lines 9a~9d to the connector substrate 200A.

[0108] In addition, since coaxial cables 9a to 9d are used as the first differential pair 2A and 2B, the coaxial cables 9a to 9d are independent of each other, and thus the characteristics in the differential change very little, so the bending resistance can be improved compared with the Twinax type communication cable. This can be seen from the results of the following durability test. That is, the 8-core Coaxial type communication cable in which the CC line 6 is omitted from the present embodiment is installed on the cable bearer (registered trademark), and a durability test of repeated movement and bending under specified conditions (moving distance: 1m, bending speed: 30 times / minute, bending radius (inside): 75mm) is carried out. The result is that even if the movement and bending exceed 30 million times, although the damage to the sheath or the transmission characteristics are affected to some extent, the required characteristics can still be maintained. On the other hand, in the Twinax type communication cable with 8 cores having the same core structure, if the movement and bending exceed 100,000 times, the transmission characteristics in the first differential pair 2A and 2B change due to mechanical damage and cause communication degradation.

[0109] [Fifth embodiment]

[0110] Fig.10 It is a cross-sectional view showing an example of a communication cable according to the fifth embodiment of the present invention. The communication cable 1 of this embodiment is a communication cable having a Vconn line 8 added to the center of the communication cable 1 of the fourth embodiment and using two filling ropes 14a and 14b formed of a resin material (e.g., polyethylene). The filling ropes 14a and 14b are an example of an intervening object. In addition, since the communication cable assembly 100 of the fifth embodiment is manufactured in the same manner as the fourth embodiment, its description is omitted.

[0111] According to the communication cable 1 of the fifth embodiment, the same effect as the fourth embodiment is achieved, and the CC line 6 and the Vconn line 8 are provided, so that the charger and the device can be connected through the communication cable 1 and the device can be charged at a high speed using power corresponding to the USB PD (Power Delivery) standard. In addition, since the coaxial lines 9a to 9d are used as the first differential pair 2A, 2B, the bending resistance can be improved.

[0112] [Example]

[0113] As described below, the communication performance (communicable distance and attenuation characteristics) of Example 1 corresponding to the first embodiment, Example 2 corresponding to the second embodiment, and the comparative example were tested and evaluated.

[0114] (Test conditions for communication distance)

[0115] The communication cable of the test object was used to connect a PC as a computer and a camera as a peripheral device. The PC used a ProBook 430G5 manufactured by HP, and the camera used a USB3.1 Gen1 uEye SE series manufactured by IDS. The communication cables of the test object are the following Example 1, Example 2, and Comparative Example. Their structures are shown in Table 1. In addition, in Table 1, T represents tin-plated soft copper wire, and AG represents silver-plated soft copper wire. In addition, in the comparative example, only the wires that can be compared with Example 1 and Example 2 are shown in Table 1.

[0116]

Table 1

[0117] Table 1

[0118]

[0119] In Example 1, a 9-core cable with a diameter of 6.8 mm was used, and AWG size 27 (conductor diameter 0.42 mm) was used as the conductors 21 of the signal lines 2a to 2d constituting the first differential pair 2A, 2B. The ratio of the conductor diameter d to the cable diameter D (d / D) was 0.062.

[0120] In Example 2, a 9-core cable with a diameter of 3.7 mm was used, and AWG size 32 (conductor diameter 0.24 mm) was used as the conductors 21 of the signal lines 2a to 2d constituting the first differential pair 2A, 2B. The ratio of the conductor diameter d to the cable diameter D (d / D) was 0.065.

[0121] In the comparative example, a 17-core cable with a diameter of 5.2 mm was used, and as the conductor constituting the signal line of the first differential pair, an AWG size of 34 (conductor diameter of 0.3 mm) was used. The ratio (d / D) of the conductor diameter d to the cable diameter D was 0.058. If the ratio (d / D) exceeds 0.07, the weight of the communication cable increases. Therefore, according to Example 1, Example 2 and the comparative example, it can be said that the preferred ratio (d / D) is 0.06 or more and 0.07 or less.

[0122] (Evaluation method of communication distance)

[0123] The image captured by the camera was sent to the PC via the communication cable of the test object, and the communication performance (communicable distance) was evaluated based on whether there was image fixation, dropout, noise, image discoloration, etc. during the 10-minute shooting. The case where there was no problem in the 10-minute image was recorded as ○, and the case where no image was projected on the PC was recorded as ×. The evaluation results are shown in Table 2.

[0124] (Attenuation characteristics)

[0125] Fig.11A This is a graph showing the attenuation characteristics when the cable length is 3 m. Fig. 11B This is a graph showing attenuation characteristics based on cable lengths (used cable lengths) corresponding to various communicable distances. Since the data transmission rate of the camera used is 5 Gbps, the attenuation characteristics around 2.5 GHz were measured.

[0126] The attenuation when the length of the communication cable is 3m is caused by the AWG size of the communication cable, such as Fig.11A As shown, the smaller the AWG size (the larger the conductor diameter), the smaller the attenuation. That is, the attenuation near the frequency of 2.5 GHz is 6 dB in Example 1, 11 dB in Example 2, and 8 dB in the comparative example. These attenuation values ​​are shown in Table 2.

[0127] like Fig. 11B As shown in Table 2, in the case of Examples 1 and 2, the attenuation in the cable length corresponding to the communicable distance is 13 dB near the frequency of 2.5 GHz, which can be estimated as the communication limit. On the other hand, in the case of the comparative example, although it is as small as 8 dB near the frequency of 2.5 GHz, it is considered that the communicable distance becomes the shortest 3 m due to other reasons such as the power supply specification based on the power line 4 (Vbus line) and the potential difference with GND. The above attenuation values ​​are shown in Table 2.

[0128]

Table 2

[0129] Table 2

[0130]

[0131] (Summary of evaluation)

[0132] (1) Compared with the comparative example (cable diameter 5.2 mm), Example 1 (cable diameter 6.8 mm) can extend the communication distance from 3 m to 6 m, which is twice as long as the comparative example (cable diameter 5.2 mm). Compared with the comparative example (cable diameter 5.2 mm), Example 2 (cable diameter 3.7 mm) has the same communication performance and can achieve lightweight communication cables.

[0133] (2) When the cable diameter is set to D and the communicable distance is set to L, as the evaluation value of the communication performance, the ratio of the communicable distance L to the cable diameter D (L / D) is L / D=6000mm / 6.8mm=882 in Example 1, L / D=3500mm / 3.7mm=946 in Example 2, and L / D=3000mm / 5.2mm=577 in the comparative example. Therefore, it can be said that the ratio L / D of the communicable distance to the cable diameter is preferably 800 or more or 880 or more, and more preferably 900 or more or 940 or more.

[0134] (Example of arrangement of core wires)

[0135] (a) to (q) in FIG. 12 are diagrams schematically showing an example of the arrangement of the core wires constituting the communication cable 1. (a) to (e) in FIG. 12 are diagrams showing the layout of the core wires that do not require high bending resistance, and (f) to (q) in FIG. 12 are diagrams showing the layout of the core wires that require high bending resistance. Figure 2 ) corresponds to (c) in FIG. 12 and ( Figure 7 ) corresponds to (i) in FIG. 12 and ( Figure 8 ) corresponds to (l) in FIG. 12 and ( Fig.10 )correspond.

[0136] In a 9-core communication cable 1 that uses a double-strand cable for the first differential pair 2A, 2B, the power line (core line No. 7) and the ground line (core line No. 8) are arranged on both sides of the CC line (core line No. 9) as shown in (a) in Figure 12 in the first embodiment, but can also be arranged on both sides of the second differential pair 3 as shown in (b) in Figure 12.

[0137] In the 10-core communication cable 1 using a double-strand cable for the first differential pair 2A, 2B, the CC line (core No. 9) and the Vconn line (core No. 10) are arranged on both sides of the power line (core No. 7) and the ground line (core No. 8) as shown in (c) of FIG. 12 in the third embodiment, but can also be arranged on both sides of the second differential pair (core No. 5, 6) as shown in (d) of FIG. 12. In addition, the power line (core No. 7) and the ground line (core No. 8) can be arranged on both sides of the second differential pair (core No. 5, 6) as shown in (e) of FIG. 12, and the CC line (core No. 9) and the Vconn line (core No. 10) can be arranged on the opposite side of the second differential pair (core No. 5, 6).

[0138] In the 9-core communication cable 1 using coaxial cables 9a to 9d for the first differential pair 2A, 2B, in the fourth embodiment, the paired coaxial cables are adjacent to each other as shown in (i) in Figure 12, but a power line (core wire No. 7) or a ground line (core wire No. 8) may be arranged between them as shown in (h) and (k) in Figure 12.

[0139] In a 10-core communication cable 1 that uses coaxial cables 9a to 9d for the first differential pair 2A, 2B, in the fifth embodiment, the paired coaxial cables are adjacent to each other as shown in (l) in Figure 12, but a power line (core wire No. 7) or a ground line (core wire No. 8) may be arranged between them as shown in (n) and (q) in Figure 12.

[0140] As mentioned above, although embodiment of this invention was described, embodiment of this invention is not limited to the said embodiment, Various deformation|transformation and implementation are possible.

Claims

1. A communication cable, wherein: The communication cable has two first differential pairs for transmitting high-speed differential signals, a second differential pair for transmitting low-speed differential signals, a power line, a ground line, and a configuration channel line for detecting the orientation of the front and back of the plug. Except for the two first differential pairs, the first differential pair is not included.

2. The communication cable according to claim 1, wherein: The communication cable has an end portion electrically connected to the plug, The plug includes a mating portion and pins having a shape and structure in accordance with the USB Type-C standard. The number of the end portions connected to the pins is configured to be smaller than the number of pins of a plug compliant with the USB Type-C standard.

3. The communication cable according to claim 1, wherein: The communication cable also has a power line for the circuit within the plug.

4. The communication cable according to claim 1, wherein: The signal line constituting the first differential pair includes a central conductor and an insulating layer covering the conductor. The ratio of the conductor diameter of the conductor to the cable diameter is greater than 0.

06.

5. The communication cable according to claim 1, wherein: The signal line constituting the first differential pair includes a central conductor and an insulating layer covering the conductor. A ratio of a conductor diameter of the conductor to a cable diameter is not less than 0.06 and not more than 0.

07.

6. The communication cable according to claim 4, wherein: The ratio of the communicable distance of the high-speed differential signal to the cable diameter is greater than 800.

7. The communication cable according to claim 1, wherein: The number of core wires is 9 or more and 14 or less.

8. The communication cable according to claim 1, wherein: A filler is further provided which is arranged near the center of the cable.

9. A communication cable assembly, wherein: have: The communication cable according to any one of claims 1 to 8; and A pair of the plugs is electrically connected to both ends of the communication cable.

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