JP2010211937A - Transmission cable with connector - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a transmission cable with a connector, superior in stability and flexibility of impedance, and capable of preventing generation of skew between twin-ax cables. <P>SOLUTION: Two cores 8 each made by coating a signal wire 6 with an insulator 7 are arrayed in parallel, an outer conductor shield 10 consisting of a plurality of conductive wires 9 to be ground are formed around the cores 8, then, a shield foil 11 and a resin layer 12 are coated on its outer periphery in this order to form a twin-ax cable 2. A plurality of the twin-ax cables 2 are housed in a loose tube 14 in free movement to structure a transmission cable 3, and each signal line 6 of the transmission cable 3 is electrically connected with a pad 15 formed at a paddle card 4 of a connector 5. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a transmission cable with a connector for transmitting a signal.

  In general, a transmission cable with a connector as shown in FIG. 7 is used to connect electrical devices and transmit electrical signals.

  As shown in FIG. 7, a conventional transmission cable 70 with a connector forms a transmission cable 83 by bundling a plurality of (in the figure, two) twinax cables 71 into one, and paddles are attached to both ends of the transmission cable 83. A connector 85 having a card 84 is connected.

  As shown in FIG. 7A, the twinax cable 71 has two pairs of cores 74 in which signal lines 72 are covered with an insulator 73 arranged in parallel, and a drain wire (GND line) in the center of the cores 74. ) 75 are arranged and bundled into one, and the outer periphery thereof is covered with a shield foil 76 and a resin layer 77.

  The transmission cable 83 is formed by twisting a plurality of twinax cables 71 and bundling them together, covering the outer periphery thereof with a jacket 79 via a resin 78, and forming an outer conductor made of a conductor 80 on the outer periphery of the jacket 79. The conductor shield 81 is covered, and the outer conductor shield 81 is covered with a sheath 82 on the outer periphery.

  As shown in FIGS. 7B and 7C, the connection between the transmission cable 83 and the connector 85 is performed by processing the terminal of the transmission cable 83 to sequentially expose the twinax cable 71, the core 74, and the signal line 72. This is done by electrically connecting the exposed signal line 72 to a pad 86 formed on the surface of the paddle card 84.

  Further, in the conventional transmission cable 70 with a connector, since GND is taken through the drain wire 75 in order to prevent reflection and crosstalk, each drain wire 75 of the transmission cable 83 is also exposed from the end of the transmission cable 83. The paddle card 84 is electrically connected to a GND pad 86 formed on the back surface of the paddle card 84.

  In addition to the transmission cable 70 with a connector, as shown in FIG. 8A, a connector using a twinax cable 87 in which two cores 74 are arranged in parallel and a drain wire 75 is arranged on the side of one core 74. There is a transmission cable 88 attached.

  As shown in FIGS. 8B and 8C, this transmission cable with connector 88 is different from the transmission cable with connector 70 that connects the signal line 72 and the drain wire 75 to the front and back surfaces of the paddle card 84, respectively. Both line 72 and drain wire 75 are connected to the surface of paddle card 84.

JP 2006-172788 A Japanese Patent Laid-Open No. 7-14438

  In the transmission cable 70 with a connector in FIG. 7, the signal line 72 is connected to the front surface of the paddle card 84 and the drain wire 75 is connected to the back surface. When disturbed, the impedance deviates from the design value, and there is a problem that a phenomenon such as reflection and crosstalk that degrades signal quality occurs.

  On the other hand, in the transmission cable 88 with a connector in FIG. 8, the signal line 72 and the drain wire 75 can be arranged on the surface of the paddle card 84, but the drain wire 75 has a structure approaching the one signal line 72 side. There is a problem in that an unbalanced electric field distribution is generated between the paired signal lines 72 and signal loss increases.

  In addition, since the drain wire 75 and the thin shield foil 76 are applied, the twinax cables 71 and 87 are originally designed with a weak GND, and the characteristics change when external force and external noise are applied.

  Further, in the transmission cables 70 and 88 with connectors, the two twinax cables 71 and 87 are bundled into one by the jacket 79 and the bending force applied to the twinax cables 71 and 87 is released. The cables 71 and 87 have a structure twisted along the cable longitudinal direction.

  Due to the structure of “twisting”, it is difficult to ensure that the line lengths of the twinax cables 71 and 87 are equal to each other. Therefore, a line length difference (skew) is inevitably generated.

  Therefore, an object of the present invention is to provide a transmission cable with a connector that is excellent in impedance stability and can suppress the occurrence of skew between twinax cables.

  The present invention has been devised to achieve the above object, and the invention of claim 1 comprises a transmission cable by bundling a plurality of twinax cables into one, and at the end of the transmission cable, In a transmission cable with a connector for connecting a connector having a paddle card, two cores formed by covering signal lines with an insulator are arranged in parallel, and an outer conductor shield composed of a plurality of conductor wires serving as a ground around these cores. In addition, a shield foil and a resin layer are sequentially coated on the outer periphery to form the twinax cable, and a plurality of the twinax cables are movably accommodated in a loose tube, and the transmission cable is accommodated. And each signal line of the transmission cable is electrically connected to a pad formed on the paddle card of the connector. It is the data with a transmission cable.

  The invention according to claim 2 is the transmission cable with a connector according to claim 1, wherein the signal line is a stranded wire formed by twisting a plurality of fine wires.

  According to a third aspect of the present invention, a GND terminal is formed at an end of the paddle card on the transmission cable side, and the outer conductor shields of the plurality of twinax cables are electrically connected to the GND terminal, respectively. A transmission cable with a connector according to claim 1 or 2.

  According to a fourth aspect of the present invention, the connector includes a connector housing base material and a connector housing cover for protecting the paddle card connecting the end portion of the transmission cable from above and below together with the end portion of the transmission cable. It is a transmission cable with a connector in any one of Claims 1-3 which have a material.

  The invention according to claim 5 is the transmission cable with a connector according to any one of claims 1 to 4, wherein the loose tube is made of polyphenylene oxide (PPO) or polyphenylene ether (PPE).

  According to a sixth aspect of the present invention, a tensile fiber having a shorter length than the twinax cable is wired between the plurality of twinax cables, and an end of the tensile fiber is bonded to the paddle card of the connector. It is a transmission cable with a connector in any one of Claims 1-5 to fix.

  A seventh aspect of the present invention is the transmission cable with a connector according to the sixth aspect, wherein an adhesive made of an epoxy resin is used for bonding the tensile strength fiber to the paddle card.

  The invention according to claim 8 is the transmission cable with connector according to claim 6 or 7, wherein the tensile strength fiber is made of polyamide resin fiber.

  According to the present invention, it is possible to provide a transmission cable with a connector that is excellent in impedance stability and that can suppress the occurrence of skew between twinax cables.

FIG. 1A is a cross-sectional view of a transmission cable of a transmission cable with a connector according to the present invention, and FIG. 1B is an enlarged view showing a connection portion between a twinax cable of the transmission cable and a paddle card of a connector. It is a perspective view. It is a disassembled perspective view of the connector of the transmission cable with a connector of FIG. It is a longitudinal cross-sectional view of a transmission cable when the transmission cable with a connector of FIG. 1 is pulled. 4A is a cross-sectional view of a transmission cable of a transmission cable with a connector according to a modification of the present invention, and FIG. 4B is a connection between the twinax cable of the transmission cable and the paddle card of the connector. It is an expansion perspective view which shows a part. It is a disassembled perspective view of the connector of the transmission cable with a connector of FIG. It is a longitudinal cross-sectional view of a transmission cable when the transmission cable with a connector of FIG. 4 is pulled. FIG. 7A is a cross-sectional view of a transmission cable of a conventional transmission cable with a connector, and FIG. 7B is an enlarged perspective view showing a connection portion between the twinax cable of the transmission cable and the paddle card of the connector. FIG. 7C is a cross-sectional view taken along line AA of FIG. 7B. FIG. 8A is a cross-sectional view of a transmission cable of a conventional transmission cable with a connector, and FIG. 8B is an enlarged perspective view showing a connection portion between the twinax cable of the transmission cable and the paddle card of the connector. FIG. 8C is a cross-sectional view taken along line BB in FIG. 8B. It is a cross-sectional view of the transmission cable of the transmission cable with a connector which shows the modification of this invention. It is a cross-sectional view of the transmission cable of the transmission cable with a connector which shows the modification of this invention. It is a cross-sectional view of the transmission cable of the transmission cable with a connector which shows the modification of this invention. It is a cross-sectional view of the transmission cable of the transmission cable with a connector which shows the modification of this invention.

  Preferred embodiments of the present invention will be described below with reference to the accompanying drawings.

  FIG. 1A is a cross-sectional view of a transmission cable of a transmission cable with a connector according to the present invention, and FIG. 1B is an enlarged view showing a connection portion between a twinax cable of the transmission cable and a paddle card of a connector. It is a perspective view.

  As shown in FIG. 1, a transmission cable 1 with a connector according to the present invention comprises a transmission cable 3 formed by bundling a plurality of twinax cables 2, and a paddle card (substrate) is formed at both ends of the transmission cable 3. The connector 5 (refer FIG. 2) which has 4 is connected.

  In the twinax cable 2, as shown in FIG. 1A, two cores 8 in which signal wires 6 are covered with an insulator 7 are arranged in parallel, and a plurality of grounds (GND) are provided around the cores 8. The outer conductor shield 10 is formed by winding the conductor wire 9 or a braid composed of the conductor wire 9 and the shield foil 11 and the resin layer 12 are sequentially coated on the outer periphery thereof. From the viewpoint of flexibility, the twinax cable 2 is preferably as thin as possible.

  The signal line 6 is composed of a stranded wire formed by twisting a plurality of thin wires 13. The signal line 6 may be a single line, but a stranded wire is preferable from the viewpoint of flexibility. If a signal line capable of transmitting an electrical signal in the GHz band is used as the signal line 6, the transmission cable 1 with a connector in the GHz band can be deployed to various devices.

  The insulator 7 is, for example, polyethylene, polypropylene, PTFE (polytetrafluoroethylene), PFA (tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer), FEP (tetrafluoroethylene-hexafluoropropylene copolymer), ETFE. (Ethylene-tetrafluoroethylene copolymer), fluororubber, and the like.

  The shield foil 11 is made of a metal foil such as silver foil or copper foil, and the resin layer 12 is made of, for example, PET (polyester tape).

  The transmission cable 3 is formed by arranging a plurality of twinax cables 2 that have been cut in advance so that the lengths of the signal lines 6 are equal to each other in parallel, or twisted and bundled into a loose tube. 14 is configured to be accommodated in a loosened state and movable in the loose tube 14 (that is, stress-free).

  The loose tube 14 is made of an elastic material such as polyphenylene oxide (PPO) or polyphenylene ether (PPE).

  Both ends of the transmission cable 3 are terminal-processed so as to be connected to the connector 5, and the twinax cable 2, the outer conductor shield 10, and the signal line 6 are sequentially exposed from both ends of the loose tube 14.

  Each exposed signal line 6 is electrically connected to a plurality of pads 15 formed on the paddle card 4 by soldering or the like.

  A GND terminal 16 is formed at the end of the paddle card 4 on the side of the twinax cable 2, and the GND terminal 16 has an outer conductor shield of the plurality of twinax cables 2 exposed from the end of the transmission cable 3. 10 are electrically connected by soldering or the like.

  The paddle card 4 generally has a multilayer structure, and a wiring pattern (not shown) is formed in the layer. For example, the GND terminal 16 is connected to the wiring pattern. The paddle card 4 is provided with a mounting hole 17 (see FIG. 2).

  Furthermore, on the paddle card 4, a transmitter IC such as emphasis can be provided at one end of the twinax cable 2 and a receiver IC such as an equalizer or CDR (clock data recovery) can be mounted at the other end. It can also be deployed as an active cable that can perform signal correction.

  As shown in FIG. 2, the connector 5 includes a connector housing base member 18 and a connector housing for sandwiching and protecting the paddle card 4 connecting the end portion of the transmission cable 3 together with the end portion of the transmission cable 3. And a cover material 19.

  The connector housing base material 18 includes a board housing portion 20 for housing the paddle card 4 and a sandwiching portion 21 having a semicircular arc-shaped groove portion for sandwiching the end portion of the loose tube 14.

  A mounting hole 22 is formed in the substrate storage portion 20, and a mounting hole 23 is also formed in the clamping portion 21.

  The paddle card 4 is fixed to the mounting hole 22 of the substrate storage unit 20 through the mounting hole 17 by screwing or the like. At this time, the end 24 of the paddle card 4 on the side where the twinax cable 2 is not connected is exposed from the ends of the connector housing base member 18 and the connector housing cover member 19.

  The connector housing cover member 19 includes a cover portion 25 that engages with the board housing portion 20 of the connector housing base member 18, and a sandwiching portion 26 that has a semicircular arc-shaped groove portion for sandwiching the end of the loose tube 14. A mounting hole 27 is formed in the sandwiching portion 26.

  The connector housing base member 18 and the connector housing cover member 19 are fixed by screwing or the like through attachment holes 23 and 27 formed in the sandwiching portion 21 and the sandwiching portion 26, respectively.

  Here, the transmission cable 1 with a connector using a twinax cable 2 of 2 pairs (one for each direction (transmission / reception direction)) has been described, but a multi-core cable such as 8 pairs (for each of four directions) is used. The present invention can also be applied to cases.

  The operation of the present embodiment will be described.

  When wiring the transmission cable 1 with a connector, the end 24 of the paddle card 4 exposed from the connector 5 is inserted into a receiving connector provided on the device side or the like, and the device and the transmission cable 1 with a connector are electrically connected. Connect.

  In the transmission cable 1 with a connector, a plurality of the twinax cables 2 are movably accommodated in the loose tube 14, so that the twinax cable 2 has a stress-free structure in the loose tube 14. Therefore, an air layer 50 is formed between the loose tube 14 and the twinax cable 2.

  Therefore, as shown in FIG. 3, when the transmission cable 1 with a connector is pulled, the tensile force acts on the loose tube 14 made of an elastic material, and the tensile force does not act on the twinax cable 2. According to the transmission cable 1, the strength against pulling can be improved.

  Further, in the case of the loose tube structure, the length of the originally formed twinax cable 2 can be cut after being physically measured and accommodated in the loose tube 14. The lengths of the cables (between the cables 2) can be equalized, and there is no need to worry about the skew caused by the conventional “twist” structure.

  Moreover, in the transmission cable 1 with a connector, an outer conductor shield 10 including a plurality of conductor wires 9 serving as GND is formed around the cores 8 and 8, and the outer conductor shield 10 is used as GND.

  Since the outer conductor shield 10 is composed of a plurality of conductor wires 9, the outer conductor shield 10 is strong in bending and hardly affected by external force. For this reason, the shield characteristics are unlikely to change, and a stable GND can be secured as compared with the case where a drain wire is used as in the prior art.

  Therefore, in the transmission cable 1 with a connector, it is not necessary to further coat the outer conductor shield 81 on the outer periphery of the twinax cable in order to secure a stable GND as in the conventional case, and the number of layers of the transmission cable can be reduced. As a result, flexibility can be improved, and it can also be used for applications where a small bending radius is required, such as inside a device.

  Further, it becomes possible to arrange the GND terminal 16 of the paddle card 4 within the same plane as the pad 15 to which the signal line 6 is connected and without greatly losing the positional relationship between the two, and impedance mismatch at the cable terminal processing portion can be achieved. It is possible to reduce the size, and it is possible to suppress the occurrence of phenomena such as reflection and crosstalk that degrade signal quality.

  Next, a modified example of the present invention will be described.

  4A is a cross-sectional view of a transmission cable of a transmission cable with a connector according to a modification of the present invention, and FIG. 4B is a connection between the twinax cable of the transmission cable and the paddle card of the connector. It is an expansion perspective view which shows a part.

  Since the configuration is basically the same as that of the transmission cable with a connector 1 in FIG. 1, components having the same functions are denoted by the same reference numerals.

  As shown in FIGS. 4A and 4B, a transmission cable 40 with a connector according to a modification of the present invention is longer than the twinax cable 2 between a plurality of twinax cables 2 arranged in parallel. A short tensile strength fiber 41 is wired, and these are movably accommodated in the loose tube 14 to form a transmission cable 42, and an end portion of the transmission cable 42 is connected to the connector 5. Each end is bonded and fixed on the paddle card 4.

  The tensile strength fiber 41 is made of a polyamide-based resin fiber such as polyparaphenylene terephthalamide, for example.

  An adhesive 43 made of an epoxy resin is used for bonding the tensile strength fiber 41 to the paddle card 4. When the tensile strength fiber 41 is bonded onto the paddle card 4, the position of the tensile strength fiber 41 is not shifted with respect to the cable longitudinal direction (the length relationship between the twinax cable 2 and the tensile strength fiber 41 is not changed). Fix it.

  As shown in FIG. 5, the end portions of the paddle card 4 and the transmission cable 42 are sandwiched between the connector housing base material 18 and the connector housing cover material 19 in the same manner as the transmission cable 1 with a connector in FIG. 1. .

  The operation of the transmission cable with connector 40 will be described.

  When the transmission cable 1 with a connector shown in FIG. 1 is pulled, a tensile force acts on the loose tube 14 made of an elastic material, and the twinax cable 2 accommodated in the loose tube 14 has a tensile force. Although it does not act, when it is pulled greatly, there is a possibility that the loosened twinax cable 2 is fully extended and a tensile force acts on the twinax cable 2.

  On the other hand, in the transmission cable 40 with a connector, the tensile fiber 41 having a shorter length than that of the twinax cable 2 is wired and the end of the tensile fiber 41 is bonded and fixed to the paddle card 4. As shown, the external force (tensile force) when the transmission cable with connector 40 is pulled acts on the tensile strength fiber 41, and no tensile force acts on the twinax cable 2.

  Therefore, according to the transmission cable 40 with a connector, the strength against pulling can be further improved.

  Moreover, like the transmission cable 1 with a connector of FIG. 1, the stability and flexibility of impedance can be improved, and the occurrence of skew between the twinax cables 2 can be suppressed.

  Another embodiment is shown in FIG. This is a cross-sectional view of the transmission cable of the connector-attached transmission cable. The same twinax cable 2 as shown in FIG. 130, the shield 131, and the loose tube 14 are sequentially coated. Since the twinax cable 2 is accommodated and configured to be movable (stress free) in the inner tube 130, an air layer 110 is formed between the inner tube 130 and the twinax cable 2. Has been. The inner tube 130, the shield 131, and the loose tube 14 can be easily handled by forming them so as to be in close contact with each other.

  The inner tube 130 is preferably made of a fluorine resin such as FEP (tetrafluoroethylene-hexafluoropyrene copolymer). This is because the hardness of the inner tube 130 is not crushed even when the transmission cable is bent. Therefore, when the transmission cable is bent, an external force is applied to the twinax cable 2 inserted from the inner tube 130 into the hole. It does not work.

  In the transmission cable 100 with a connector, a shield 131 is formed by laterally winding or vertically attaching a wire (wire) on the outer peripheral side of the inner tube 130, and the shield 131 is further covered with the loose tube 14. It is manufactured by a method of inserting the twinax cable 2 into the inner tube 130.

  The modification of the transmission cable 100 with a connector which concerns on FIG. 9 is shown to FIGS.

  A transmission cable 101 with a connector shown in FIG. 10 is a metal tape with a resin film (for example, a PET (polyethylene terephthalate) film with aluminum, etc.) instead of the wire used for the shield 131 of the transmission cable with a connector 100 shown in FIG. The metal tape 133 is wound so that the resin film 132 side made of PET is in contact with the outer peripheral surface of the inner tube 130, and the shield 131 is formed. Then, the shield 131 is coated with the loose tube 14.

  A transmission cable 102 with a connector shown in FIG. 11 uses a conductive sheet (for example, conductive rubber) instead of the wire used for the shield 131 of the transmission cable 100 with a connector shown in FIG. After the adhesive 135 made of resin is applied to the outer peripheral surface of 130, the conductive sheet 134 is wound to form the shield 131 and then covered with the loose tube 14.

  A transmission cable 103 with a connector shown in FIG. 12 uses a conductive tube (for example, conductive rubber) instead of a wire used for the shield 131 of the transmission cable 100 with a connector shown in FIG. After the outer periphery of 130 is covered with a conductive tube 136 to form a shield 131, the outer periphery of 130 is further covered with a loose tube 14.

  Since the transmission cable with a connector shown in FIGS. 9 to 12 has a configuration in which a shield 131 is also provided on the outer peripheral side of the twinax cable 2, noises flying from the outside can be blocked, so that the internal signal line 6 The outer conductor shield 10 and the shield foil 11 can be prevented from being affected by external noise. Moreover, the transmission cable with a connector shown in FIGS. 9 to 12 can improve the stability of impedance and suppress the occurrence of skew between the twinax cables 2, similarly to the transmission cable 1 with a connector of FIG. 1.

  Further, the tensile strength fiber 41 used in the transmission cable with connector 40 shown in FIG. 4 is also used in the transmission cable with connector shown in FIGS.

1 Transmission cable with connector 2 Twinax cable 3 Transmission cable 4 Paddle card 5 Connector 6 Signal line 7 Insulator 8 Core 9 Conductor line 10 Outer conductor shield 11 Shield foil 12 Resin layer 14 Loose tube

Claims (8)

In a transmission cable with a connector in which a plurality of twinax cables are bundled into one to form a transmission cable, and a connector having a paddle card is connected to the end of the transmission cable.
Two cores formed by covering signal lines with an insulator are arranged in parallel, and an outer conductor shield composed of a plurality of conductor wires serving as a ground is formed around these cores, and a shield foil and a resin layer are formed on the outer periphery thereof. The twinax cable is formed by covering sequentially, and a plurality of the twinax cables are movably accommodated in a loose tube to form the transmission cable, and each signal line of the transmission cable is connected to the connector. A transmission cable with a connector, wherein the transmission cable is electrically connected to a pad formed on the paddle card.   The transmission cable with a connector according to claim 1, wherein the signal line includes a stranded wire formed by twisting a plurality of thin wires.   The GND terminal is formed in the edge part of the said paddle card | curd by the side of the said transmission cable, The external conductor shield of the said several twinax cable is electrically connected to the GND terminal, respectively. Transmission cable with connector.   2. The connector includes a connector housing base material and a connector housing cover material for sandwiching and protecting the paddle card connecting the end portions of the transmission cable from above and below together with the end portions of the transmission cable. The transmission cable with a connector in any one of -3.   The transmission cable with a connector according to claim 1, wherein the loose tube is formed of polyphenylene oxide (PPO) or polyphenylene ether (PPE).   6. A tensile strength fiber having a shorter length than the twinax cable is wired between the plurality of twinax cables, and an end portion of the tensile strength fiber is bonded and fixed on the paddle card of the connector. A transmission cable with a connector according to any one of the above.   The transmission cable with a connector according to claim 6, wherein an adhesive made of an epoxy resin is used for bonding the tensile strength fiber to the paddle card.   The transmission cable with a connector according to claim 6, wherein the tensile strength fiber is made of a polyamide-based resin fiber.

Images