JP2013239271A - Connection structure, connection method, and differential signal transmission cable - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a connection structure, a connection method, and a differential signal transmission cable, which are capable of facilitating electrical connection between a shield and a substrate, preventing an insulator from being deformed and melted during solder connection work, and preventing deterioration in transmission characteristics.SOLUTION: In a connection structure, a differential signal transmission cable 10 is connected to a substrate via a connection member 20 which includes a body part 21 mounted on a shield 13 exposed at an end part of the cable and one or more projection parts 22 projectingly formed in the body part 21. The connection member 20 is connected to the shield 13 via the body part 21, and also connected to the substrate via the projection parts 22.

Description

  The present invention relates to a connection structure between a differential signal transmission cable and a substrate, a connection method between the differential signal transmission cable and a substrate, and a differential signal transmission cable.

  Many high-speed transmission cables connecting electronic devices propagate differential signals. In this cable, two cores (inner conductor) and an insulator are twisted in the longitudinal direction or arranged in parallel, and a shield (outer conductor) for suppressing the influence of external noise is wound outside the insulator. The structure is The insulator is mainly made of foamed polyethylene, and the shield is made of metal foil tape.

  When conducting between the differential signal transmission cable and the electronic device, the core wire is soldered to a connector wired in the electronic device or a signal pad of the printed circuit board to be electrically connected. Further, when connecting to the substrate, it is necessary to connect the shield exposed at the end of the differential signal transmission cable to the ground electrode on the substrate in order to obtain ground.

  As a method of connecting the shield to the ground electrode on the substrate, there is a method of connecting the shield directly to the ground electrode on the substrate by solder when there is no drain line.

  In addition, when a drain line is provided, there is a method of connecting the drain line to a ground electrode on the substrate by soldering (see, for example, Patent Document 1 and Patent Document 2).

JP 2002-289047 A JP 2003-297155 A

  However, when there is no drain wire, that is, according to the method in which the shield is directly connected to the ground electrode on the substrate by solder, the insulation (foamed polyethylene) in the cable is caused by heating or pressurizing during solder connection work. Is deformed or melted, resulting in variations (fluctuations) in characteristic impedance and significant deterioration in skew characteristics, resulting in a problem of poor transmission characteristics.

  In addition, the method of connecting the drain line to the ground electrode on the substrate by soldering also deteriorates the transmission characteristic due to the deformation of the insulator by the drain line, and thus meets the recent demand for further improvement of the transmission characteristic. There is a problem that it is difficult. For example, as in Patent Document 1, if the insulator has a drain line at the right end or the left end, the drain line crushes one insulator in the jacket (sheath) coating process, so the differential mode balance is lost, Electrical characteristics deteriorate at high frequencies in the GHz band.

  Furthermore, as in Patent Document 2, when the drain line is provided at the center of the insulator, the balance of the differential mode is less distorted than when the drain line is provided at the right end or the left end, but the cable terminal is connected to the connector or the printed board. In this case, since the heights of the lead-out portions of the core line and the drain line are different, the lead-out length of the drain line becomes longer than when the drain line is provided at the right end or the left end. As a result, the electrical characteristics are deteriorated, and the difficulty of connecting the drain wires is increased.

  Therefore, an object of the present invention is to provide a connection structure, a connection method, and a differential that facilitate electrical connection between a shield and a substrate, prevent deformation and melting of an insulator during solder connection work, and prevent deterioration of transmission characteristics. It is to provide a signal transmission cable. In the present invention, the connection to the board includes not only direct connection but also connection through a connector or the like (that is, the direct connection destination is a connector or the like).

  In order to achieve the above object, the present invention provides a connection structure, a connection method, and a differential signal transmission cable described in [1] to [12] below.

[1] A differential signal transmission cable is connected to a substrate through a connecting member including a main body portion that is placed on a shield exposed at an end portion of the cable and one or more protrusion portions that are formed to protrude from the main body portion. A connected connection structure,
The connection structure is characterized in that the connection member is connected to the shield via the main body and is connected to the substrate via the protrusion.
[2] The connection structure according to [1], wherein the connection member is fixed to the shield with solder at a predetermined portion of the main body.
[3] The connection structure according to [1] or [2], wherein the connection member is fixed to the shield with solder at an opening or a notch provided in the main body.
[4] The connection structure according to any one of [1] to [3], wherein the connection member includes two or more protrusions.
[5] The connecting member includes the main body portion placed on a shield exposed at an end portion of one or more differential signal transmission cables and the number of the differential signal transmission cables plus one protrusion portion. The connection structure according to any one of [1] to [4], wherein the connection structure is provided.
[6] The connection member includes the main body portion and the two projecting portions placed on a shield exposed at an end portion of the one differential signal transmission cable. Thru | or the connection structure as described in any one of [5].
[7] The connection member includes the main body and the three protrusions that are placed on the shield exposed at the ends of the two differential signal transmission cables. Thru | or the connection structure as described in any one of [5].
[8] The above [1] to [7], wherein the protruding portion is protruded from the main body portion so that the interval between adjacent protruding portions is equal to the width of the cable. ] The connection structure as described in any one of.
[9] The above-mentioned [1], wherein the protruding portion is formed to protrude from the main body portion in a direction substantially parallel to the core wire exposed at the end of the differential signal transmission cable. Thru | or the connection structure as described in any one of [8].
[10] The above-mentioned [1], wherein the protrusion is formed to protrude from the main body so as to be the same height as the core wire exposed at the end of the differential signal transmission cable. ] To [9]. The connection structure according to any one of [9].
[11] A connection method for connecting the differential signal transmission cable to the substrate via the connection member used in the connection structure according to any one of [1] to [10],
After placing the main body portion of the connection member on the shield, the main body portion is fixed to the shield with solder supplied to a predetermined portion of the main body portion.
[12] A differential signal transmission cable used in the connection structure according to any one of [1] to [10], wherein the connection member is connected to the shield exposed at one or both ends. A differential signal transmission cable characterized by the above.

  According to the present invention, a connection structure, a connection method, and differential signal transmission that facilitate electrical connection between a shield and a substrate, prevent deformation and melting of an insulator during solder connection work, and prevent deterioration of transmission characteristics. Cables can be provided.

It is a perspective view which shows the end of the cable for differential signal transmission used for the connection structure which concerns on the 1st Embodiment of this invention. It is the II-II sectional view taken on the right side of FIG. It is a perspective view which shows the end of the cable for differential signal transmission used for the connection structure which concerns on the 2nd Embodiment of this invention. It is a perspective view which shows the end (before connection) of the cable for differential signal transmission used for the connection structure which concerns on the 3rd Embodiment of this invention. It is the schematic of the connection member used for the connection structure which concerns on the 4th Embodiment of this invention.

[First embodiment of the present invention]
(Configuration of differential signal transmission cable used for connection structure)
FIG. 1 is a perspective view showing one end of a differential signal transmission cable used in the connection structure according to the first embodiment of the present invention. 2 is a cross-sectional view taken along the line II-II in the right view of FIG.

  The differential signal transmission cable used in the connection structure according to the first embodiment includes a cable 10 and a connection member 20 connected to shields 13 exposed at both ends of the cable 10. The connection member 20 may be connected only to one end of the cable 10 (the same applies to the second to fourth embodiments described later).

  The cable 10 is not particularly limited. For example, as shown in FIG. 1, a pair of core wires 11 arranged in parallel, an insulator 12 that collectively covers the pair of core wires 11, and insulation A differential signal transmission cable including a shield 13 covering the body 12 and a jacket 14 covering the shield 13 can be used. The cable 10 is connected to a substrate (not shown) through the connection member 20. Since the ground can be taken via the connection member 20, the drain line can be dispensed with.

  The core wire 11 is, for example, a single wire of a good electric conductor such as copper, or a single wire obtained by plating the electric conductor.

  The insulator 12 is formed using a material having a small dielectric constant and dielectric loss tangent, for example. This material is, for example, a foamed insulating resin such as polytetrafluoroethylene (PTFE), polyethylene, perfluoroalkoxyalkane (PFA), foamed polyethylene or foamed Teflon (Teflon is a registered trademark).

  As shown in FIG. 1, when using an insulator 12 that collectively covers a pair of core wires 11, the cross-sectional shape of the insulator 12 is preferably an elliptical shape that is long in the direction in which the pair of core wires 11 are arranged. Moreover, it is also preferable to set it as the flat ellipse shape which has a flat part parallel with the arrangement direction of a pair of core wire 11. FIG.

  The shield 13 can be formed by, for example, winding a metal foil tape around the insulator 12 in a spiral shape. The metal foil tape is formed by bonding a plastic tape such as PET (polyethylene terephthalate) and a metal foil such as copper foil or aluminum foil.

  The jacket 14 is also referred to as a sheath, and is formed using, for example, polyvinyl chloride (PVC) resin, polyolefin resin, or fluororesin.

  The connection member 20 includes a main body 21 that is placed on the shield 13 exposed at the end of the cable 10 and two protrusions 22 that are formed to protrude from the main body 21.

  The connection member 20 is connected to the shield 13 via the main body 21 and is connected to the substrate via the protrusion 22.

  The main body portion 21 can take various shapes such as a curved plate shape, a flat plate shape, a rod shape, and a tape shape. However, as shown in FIG. 1, the main body portion 21 may be composed of a plate-like member that curves along the outer periphery of the shield 13. preferable. As a result, the contact area with the shield 13 is increased, and the shield 13 can be placed on the shield 13 in a stable state, so that the fixing work with solder is facilitated.

  The size of the main body 21 is not particularly limited, and can be appropriately adjusted according to the thickness of the cable.

  The connecting member 20 is fixed to the shield 13 with solder 30 at a predetermined location of the main body 21. Although the predetermined location is not particularly limited, in the present embodiment, it is the opening 21 </ b> A provided in the main body 21. As shown in FIG. 1, the opening 21A is preferably provided in the vicinity of the approximate center in the cable width direction on the side opposite to the side to which the substrate is connected (the upper side in FIG. 1). Although only one opening 21A is provided here, two or more openings may be provided. When providing two or more, it is preferable to provide in the position symmetrical with respect to the center line of a cable longitudinal direction in the cable width direction.

  The number of the protrusions 22 may be one, or three or more. However, the number of the differential signal transmission cables 10 on which the main body 21 is mounted (one in the present embodiment) +1 is set to two. As shown in FIG. 1, it is preferable that there are two cables, one on each side of the left end and the right end in the width direction of the cable 10. That is, the protruding portion 22 is formed to protrude from the main body portion 21 so that the interval between two adjacent protruding portions is equal to the width of the cable 10, so that transmission characteristics can be balanced. Is preferable.

  As shown in FIG. 1, the protrusions 22 are preferably formed so as to protrude one by one from the main body 21 in a direction substantially parallel to the core wire 11 exposed at the end of the cable 10. The shape of the protrusion 22 is not particularly limited, and various shapes such as a round bar shape and a square bar shape can be taken, but it is desirable to have a shape that does not easily break. The length of the protrusion 22 is not particularly limited, and can be adjusted as appropriate.

  As shown in FIG. 1, the protrusion 22 is preferably formed so as to protrude at the same height as the core wire 11 exposed at the end of the cable 10. By using the same height, it is preferable that the core wire 11 need not be bent downward and can be connected straight to the substrate.

  The material of the connection member 20 is not particularly limited, and any material having electrical conductivity may be used, and metal materials such as SUS, copper, silver, tin, and aluminum can be used. The main body 21 and the protrusion 22 are preferably made of the same material.

(Connection procedure for connection structure)
As a connection procedure of the connection structure according to the first embodiment of the present invention, after placing the main body portion 21 of the connection member 20 shown in FIG. The main body 21 is fixed to the shield 13 by the solder 30 supplied to the provided opening 21A (the right diagram in FIG. 1 and FIG. 2). As shown in FIG. 2, the amount of solder 30 to be supplied is preferably such that an appropriate amount of solder overflows from the opening 21 </ b> A to the surface of the main body 21. Thereafter, the connecting member 20 is fixed with the solder 30 and the connected cable 10 is connected to the substrate by soldering or the like with the tip portion of the protrusion 22 parallel to the substrate.

  Alternatively, after the main body 21 of the connecting member 20 is placed on the shield 13, the tip of the protrusion 22 is connected to the substrate, and then the main body 21 is attached by the solder 30 supplied to the opening 21 </ b> A provided in the main body 21. It may be fixed to the shield 13.

(Effects of the first embodiment of the present invention)
According to the present embodiment, the following effects can be obtained.
(1) A connection structure, a connection method, and a differential signal transmission cable that facilitate electrical connection between the shield and the substrate, prevent deformation and melting of the insulator during solder connection work, and prevent deterioration of transmission characteristics. Can be provided.
(2) Since the drain line can be dispensed with, it is possible to prevent electrical characteristic deterioration (such as variations in characteristic impedance at the connecting portion and deterioration in skew characteristics) accompanying the drain line drawing.
(3) Since the main body can be connected to the shield only by spotting a small amount of solder at the opening provided in the main body, the effect of preventing deformation and melting of the insulator during the solder connection operation is high.
(4) Since the projecting portion is provided on the connection member, the ease of connection between the shield and the substrate is equivalent to the case of having a drain line.
(5) A predetermined location where the solder is spotted can be determined arbitrarily, and soldering can be performed at a location where the influence on the degradation of the transmission characteristics is small, so that the effect of preventing the degradation of the transmission characteristics is high.

[Second Embodiment of the Present Invention]
(Configuration of differential signal transmission cable used for connection structure)
FIG. 3 is a perspective view showing one end of a differential signal transmission cable used in the connection structure according to the second embodiment of the present invention.

  The connection member 120 according to the second embodiment of the present invention includes a main body 121 placed on the shield 13 exposed at the end of the cable 10 and two protrusions 122 formed to protrude from the main body 121. The predetermined portion of the main body 121 fixed to the shield 13 by the solder 30 is a notch 121A provided in the main body 121, and the predetermined portion is the opening 21A provided in the main body 21. This is different from the first embodiment.

  As shown in FIG. 3, one notch 121 </ b> A is provided at a position symmetrical in the cable width direction with respect to the center line in the cable longitudinal direction on the side opposite to the side to which the board is connected (upper side in FIG. 3). Preferably, a total of two are provided. Here, two notches 121A are provided, but one or three or more may be provided. When one is provided, it is preferably provided at a position near the approximate center in the cable width direction.

  The width and length of the cutout 121A are not particularly limited as long as the connection member 120 can be fixed to the shield 13 by filling the cutout 121A with solder.

  Since other points are the same as those of the first embodiment, description thereof is omitted.

(Effect of the second embodiment of the present invention)
According to the present embodiment, the same effects as those of the first embodiment can be obtained. However, “opening” in the above (3) is read as “notch”.

[Third embodiment of the present invention]
(Configuration of differential signal transmission cable used for connection structure)
FIG. 4 is a perspective view showing one end (before connection) of a differential signal transmission cable used in the connection structure according to the third embodiment of the present invention.

  The differential signal transmission cable used for the connection structure according to the third embodiment includes four cables 10 arranged in parallel, and a connection member 220 connected to the shield 13 exposed at both ends or one end of each cable 10. Is provided.

  The connection member 220 includes a main body 221 placed on the shield 13 exposed at the ends of the four cables 10 and five protrusions 222 formed to protrude from the main body 221.

  The connection member 220 is connected to the shield 13 via the main body 221 and is connected to the substrate via the protrusion 222.

  The number of the protrusions 222 may be 1 to 4 or 6 or more, but the number of the differential signal transmission cables 10 on which the main body 221 is mounted (4 in this embodiment) +1 and 5 is as follows. As shown in FIG. 4, it is preferable that there are a total of five cables, one on each side of the leftmost and rightmost ends in the width direction of the cable 10 and one between each cable 10. . In other words, the protrusion 222 is formed to protrude from the main body 221 so that the distance between two adjacent protrusions is equal to the width of the cable 10, so that transmission characteristics can be balanced. Is preferable. In addition, signal interference can be prevented by providing one cable between each cable 10.

(Connection procedure for connection structure)
As a connection procedure of the connection structure according to the third embodiment of the present invention, the main body 221 of the connection member 220 shown in FIG. 4 is placed on the shield 13 of the four cables 10 and then provided on the main body 21. The main body 221 is fixed to the shield 13 using the heater tool 40 by the solder 30 supplied to the openings 221A (thread-like (rod-like) or plate-like solder that can be supplied collectively to the four openings 221A). After that, the connecting member 220 is fixed with the solder 30 and the four cables 10 that have been connected are connected to the substrate by soldering or the like with the tip portion of the protrusion 222 parallel to the substrate.

  Since other points are the same as those of the first embodiment, description thereof is omitted.

  In the present embodiment, four cables 10 are arranged in parallel, but may be two, three, or five or more. In this case, it is desirable to project the protrusions 222 from the main body 221 between the cables 10. That is, it is preferable that the connection member includes the number of the cables 10 plus one protrusion.

(Effect of the third embodiment of the present invention)
According to the present embodiment, the following effects can be obtained.
(1) The same effects as those of the first embodiment can be obtained.
(2) A large number of cables 10 can be connected at the same time, workability can be improved, and both straightening and collective connection are possible.

[Fourth embodiment of the present invention]
(Configuration of differential signal transmission cable used for connection structure)
FIG. 5 is a perspective view showing one end of a differential signal transmission cable used in the connection structure according to the fourth embodiment of the present invention.

  The connection member 320 according to the fourth embodiment of the present invention includes a main body portion 321 placed on the shield 13 exposed at the end of the cable 10 and two projecting portions 322 protruding from the main body portion 321. It is different from the first to third embodiments in that the predetermined portion of the main body 321 that is provided and fixed to the shield 13 by the solder 30 is not the opening 21A or the notch 121A.

  As shown in FIG. 5, the main body 321 according to the fourth embodiment of the present invention has a solder 30 near the center in the cable width direction on the side opposite to the side to which the board is connected (the upper side in FIG. 5). It is preferable to be fixed by. The main body portion 321 is formed such that the length in the cable longitudinal direction is shorter than the length in the cable longitudinal direction of the exposed portion of the shield 13 so that the solder 30 can be directly heat-melted to fix the main body portion 321 to the shield 13. Yes. As shown in FIG. 5, soldering is preferably performed on both sides in the cable longitudinal direction across the main body 321, but it may be performed only on one side. In this embodiment, only one place in the cable width direction is fixed, but two or more places may be fixed. When fixing two or more places, it is preferable to fix at a symmetrical position in the cable width direction with respect to the center line in the cable longitudinal direction.

  Since other points are the same as those of the first embodiment, description thereof is omitted.

(Effect of the fourth embodiment of the present invention)
According to the present embodiment, the same effects as those of the first embodiment (except for the above (3)) are obtained.

[Other Embodiments of the Present Invention]
As mentioned above, although embodiment of this invention was described, this invention is not limited to these embodiment, In the range which does not deviate from the main point of invention, various deformation | transformation implementation is possible.

10: Cable (differential signal transmission cable)
DESCRIPTION OF SYMBOLS 11: Core wire, 12: Insulator, 13: Shield, 14: Jacket 20, 120, 220, 320: Connection member 21, 121, 221, 321: Main part 21A, 221A: Opening 121A: Notch 22, 122, 222 322: Protrusion 30: Solder 40: Heater tool

Claims (12)

The differential signal transmission cable is connected to the substrate via a connection member including a main body portion placed on a shield exposed at an end of the cable and one or more protrusions formed to protrude from the main body portion. A connection structure,
The connection structure is characterized in that the connection member is connected to the shield via the main body and is connected to the substrate via the protrusion.   The connection structure according to claim 1, wherein the connection member is fixed to the shield with solder at a predetermined portion of the main body.   The connection structure according to claim 1, wherein the connection member is fixed to the shield with solder at an opening or a notch provided in the main body.   The connection structure according to any one of claims 1 to 3, wherein the connection member includes two or more protrusions.   The connection member includes the main body portion mounted on a shield exposed at an end portion of one or more differential signal transmission cables and the number of the differential signal transmission cables plus one protrusion portion. The connection structure according to any one of claims 1 to 4, characterized in that:   The said connection member is equipped with the said main-body part mounted on the shield exposed at the edge part of the said one cable for differential signal transmission, and the two said projection parts, The any one of Claim 1 thru | or 5 characterized by the above-mentioned. The connection structure according to claim 1.   The said connection member is provided with the said main-body part mounted on the shield exposed at the edge part of two said differential signal transmission cables, and three said projection parts, The any one of Claim 1 thru | or 5 characterized by the above-mentioned. The connection structure according to claim 1.   8. The projecting portion according to claim 1, wherein the projecting portion protrudes from the main body portion so that an interval between adjacent projecting portions is equal to a lateral width of the cable. 9. The connection structure described in 1.   9. The projection according to claim 1, wherein the protrusion is formed to protrude from the main body in a direction substantially parallel to a core wire exposed at an end of the differential signal transmission cable. The connection structure according to claim 1.   10. The protrusion according to claim 1, wherein the protrusion is formed to protrude from the main body so as to be the same height as the core wire exposed at the end of the differential signal transmission cable. The connection structure according to any one of the above. A connection method for connecting the differential signal transmission cable to the substrate via the connection member used in the connection structure according to any one of claims 1 to 10,
After placing the main body portion of the connection member on the shield, the main body portion is fixed to the shield with solder supplied to a predetermined portion of the main body portion.   The differential signal transmission cable used in the connection structure according to claim 1, wherein the connection member is connected to the shield exposed at one end or both ends. Cable for differential signal transmission.

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