Multi-core cable assemblies

Abstract

To provide a multicore cable assembly comprising a multicore cable which uses a plurality of insulation-coated electric wires as a core wire, in which bending tendency of insulation-coated electric wire is reduced, and workability of terminal treatment is improved.SOLUTION: A multicore cable assembly 100 comprises: a multicore cable which is used as a catheter cable 10 of medical equipment, and in which a plurality of insulation-coated electric wires 2 are stranded to constitute a wire bundle 20; and a terminal member 6 for which an electrode pad is provided, where the insulation-coated electric wire 2 has a metal conductor wire 21 having a conductor diameter of 0.010 mm or more and 0.085 mm or less and an insulation layer 22 coating the metal conductor wire 21, and is plastically extended at the elongation of 0.5% or more and 10.0% or less in a longitudinal direction, and the plastically extended insulation-coated electric wire 2 is electrically connected to the electrode pad 61.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to a multi-core cable assembly including a multi-core cable in which a plurality of insulated electric wires are twisted together. [Background technology]

[0002] Conventionally, a multi-core cable in which a plurality of insulating coated electric wires are twisted together has been used as a catheter cable for a medical device, for example. The present applicant has proposed such a multi-core cable as described in Patent Documents 1 and 2. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 9-219115 [Patent Document 2] Japanese Patent Application Publication No. 10-134649 Summary of the Invention [Problem to be solved by the invention]

[0004] In recent years, the number of core wires in catheter cables has been increasing due to the sophistication of medical devices, while there is a demand for thinner cable outer diameters in order to reduce the burden on subjects. For this reason, core wires with extremely thin conductor diameters of, for example, less than 0.1 mm have come to be used. However, when such extremely thin core wires are used, the core wires tend to bend easily, and each core wire may bend irregularly at the cable end, significantly reducing the workability of terminal processing.

[0005] The present invention has been made in consideration of the above-mentioned circumstances, and an object of the present invention is to provide a multi-core cable assembly having a multi-core cable that uses a plurality of insulating-coated electric wires as core wires, which can reduce the bending tendency of the insulating-coated electric wires, thereby improving the workability of terminal processing. [Means for solving the problem]

[0006] In order to solve the above-mentioned problems, the present invention provides a multi-core cable assembly, which is used as a catheter cable for medical devices and includes a multi-core cable in which a plurality of insulating coated electric wires are twisted together to form a wire bundle, and a terminal member on which an electrode pad is provided, wherein the insulating coated electric wire has a metal conductor wire with a conductor diameter of 0.010 mm or more and 0.085 mm or less and an insulating layer coating the metal conductor wire, and is plastically stretched in the longitudinal direction at an elongation rate of 0.5% or more and 10.0% or less, and the plastically stretched insulating coated electric wire is electrically connected to the electrode pad.

[0007] In addition, for the purpose of solving the above-mentioned problems, the present invention provides a multi-core cable assembly in which the above-mentioned multi-core cable is twisted such that a specific insulation-coated electric wire among the plurality of insulation-coated electric wires is not always present in the center or outer periphery of the bundle of electric wires. Effect of the Invention

[0008] According to the multi-core cable assembly of the present invention, bending tendency of a plurality of insulating covered electric wires is reduced, and the workability of terminal processing of the multi-core cable is improved. [Brief description of the drawings]

[0009] [Figure 1] 1A is an explanatory view showing a state in which a multi-electrode catheter in which a multi-core cable according to an embodiment of the present invention is used as a catheter cable, and FIG. 1B is a cross-sectional view of the catheter cable. [Diagram 2] 1A is an explanatory diagram showing an end of a catheter cable before a plurality of insulating coated electric wires are connected to a substrate, and FIG. 1B is an explanatory diagram showing a state in which a plurality of insulating coated electric wires of the catheter cable are connected to a substrate. [Diagram 3]FIG. 13 is an explanatory diagram showing, as a comparative example, an example of a plurality of insulation-coated electric wires at the end of a catheter cable in which the metal conductor wire is not plastically stretched in the longitudinal direction. [Figure 4] FIG. 4(a) is an explanatory diagram showing an enlarged view of part A in FIG. 3. FIG. 4(b) is a cross-sectional view of an insulation-coated electric wire in the BB line in FIG. [Diagram 5] FIG. 2 is an explanatory diagram showing a configuration example of a manufacturing apparatus for twisting together a plurality of insulating covered electric wires to manufacture an electric wire bundle. [Figure 6] 1 is a photograph showing a catheter cable according to an embodiment. [Figure 7] 1 is a photograph showing a plurality of insulation-coated electric wires that have not been plastically stretched, and a bind tape wound around the outer circumference of the plurality of insulation-coated electric wires. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] [Embodiment Mode] Fig. 1(a) is an explanatory diagram showing a state of use of a multi-electrode catheter 1 in which a multi-core cable according to an embodiment of the present invention is used as a catheter cable 10. This multi-electrode catheter 1 is an example of a medical device in which a multi-core cable according to the present embodiment is used. Fig. 1(b) is a cross-sectional view of the catheter cable 10.

[0011] The multi-electrode catheter 1 has a catheter cable 10 and a handle 11 that is operated by an operator such as a doctor. One longitudinal end of the catheter cable 10 is housed in the handle 11, and the other longitudinal end is inserted into the body of a subject P for examination or treatment. In Fig. 1(a), the portion of the catheter cable 10 that is inserted into the body of the subject P is shown by a dashed line.

[0012] As shown in FIG. 1(b), the catheter cable 10 includes a plurality of insulation-coated electric wires 2, a bind tape 3 wound around the outer circumference of the plurality of insulation-coated electric wires 2, a shield conductor 4 arranged around the outer circumference of the bind tape 3, and a tubular sheath 5 arranged around the outer circumference of the shield conductor 4. The plurality of insulation-coated electric wires 2 are twisted together to form an electric wire bundle 20. The insulation-coated electric wires 2 are signal wires that transmit electric signals. The sheath 5 is made of a fluororesin such as PFA (a copolymer of tetrafluoroethylene and perfluoroalkoxyethylene), and covers the plurality of insulation-coated electric wires 2 together with the bind tape 3 and the shield conductor 4.

[0013] In this embodiment, the catheter cable 10 has 25 insulation-coated electric wires 2, and these insulation-coated electric wires 2 are twisted together so that a specific insulation-coated electric wire 2 is not always present in the center or outer periphery of the wire bundle 20. However, the number of insulation-coated electric wires 2 in the catheter cable 10 is not limited to this, and may be, for example, eight or more.

[0014] The insulation-coated electric wire 2 has a metal conductor wire 21 made of a metal with good electrical conductivity, and an insulating layer 22 that coats the metal conductor wire 21. The metal conductor wire 21 is a solid wire having a circular cross section, and is made of, for example, copper or a copper alloy, or aluminum or an aluminum alloy. More specifically, oxygen-free copper or low-oxygen copper can be suitably used as the material for the metal conductor wire 21. The conductor diameter D21 of the metal conductor wire 21 is 0.010 mm or more and 0.085 mm or less.

[0015] The insulating layer 22 is made of a thermosetting resin such as polyurethane, polyester, polyesterimide, polyamideimide, or polyimide. In this embodiment, the insulation-coated electric wire 2 is an enameled wire, and the insulating layer 22 is formed by applying a liquid resin material before hardening to the outer periphery of the metal conductor wire 21 and then hardening the resin material by heating.

[0016] The multi-electrode catheter 1 is connected to a console (not shown) by a console cable 12 extending from the handle 11. The console is an information processing device equipped with a microprocessor, memory, etc., which amplifies signals sent from the subject P's body via the multiple insulated electric wires 2, and outputs image signals for displaying on a display the internal condition of the subject P obtained from the amplified signals. The handle 11 contains a board having multiple pads to which the multiple insulated electric wires 2 are connected. The signals sent from the subject P's body are relayed by this board and sent to the console by the console cable 12.

[0017] Fig. 2(a) is an explanatory diagram showing the cable end of the catheter cable 10 before the multiple insulation-coated electric wires 2 are connected to the substrate 6 in the handle 11. Fig. 2(b) is an explanatory diagram showing the multiple insulation-coated electric wires 2 connected to the substrate 6.

[0018] The substrate 6 is one aspect of a terminal member to which a plurality of insulating coated electric wires 2 are connected at the end of the catheter cable 10. The catheter cable 10 and the substrate 6 constitute a multi-core cable assembly 100. At the longitudinal end of the catheter cable 10, a predetermined length of the sheath 5 is removed, and a plurality of insulating coated electric wires 2 extend from the end of the sheath 5. The bind tape 3 and the shield conductor 4 are cut and removed near the end of the sheath 5.

[0019] The substrate 6 is an FPC (flexible printed circuit board), and a surface 60a of a flexible, plate-like base material 60 is provided with a plurality of electrode pads 61 and a plurality of wiring patterns 62 extending from each of the electrode pads 61. The insulating layer 22 of the insulating coated wire 2 is removed at the tip end connected to the electrode pad 61 to expose the metal conductor wire 21, which is electrically connected to the electrode pad 61. The electrode pad 61 has a rectangular shape when viewed from a direction perpendicular to the base material 60, and the metal conductor wire 21 extends on the electrode pad 61 along the long side direction.

[0020] The operation of connecting the metal conductor wire 21 to the electrode pad 61 is performed manually by an operator, for example, under a magnifying glass or a microscope. In Fig. 2(b), the metal conductor wire 21 is illustrated as being connected to the electrode pad 61 by solder 63, but this is not limiting, and the metal conductor wire 21 may be welded to the electrode pad 61 by a conductive adhesive. Also, the metal conductor wire 21 may be welded to the electrode pad 61 by, for example, ultrasonic waves.

[0021] When connecting the metal conductor wire 21 to the electrode pad 61, it is desirable from the viewpoint of workability that there is little undulation of the insulation-coated electric wire 2 extending from the sheath 5. Here, "undulation" refers to the irregular bending of the insulation-coated electric wire 2 that occurs when the sheath 5 at the cable end is removed and the insulation-coated electric wire 2 is released. If the insulation-coated electric wire 2 is largely undulated, it is difficult to arrange the metal conductor wire 21 along the long side direction of the electrode pad 61 during the connection work, and short circuits between adjacent electrode pads 61 are likely to occur.

[0022] In this embodiment, each of the multiple insulation covered electric wires 2 is plastically stretched in the longitudinal direction in order to reduce the bending tendency of the insulation covered electric wire 2 and suppress undulation of the insulation covered electric wire 2 at the portion extended from the sheath 5. The elongation percentage of the insulation covered electric wire 2 by this plastic stretching is 0.5% or more and 10.0% or less. If the elongation percentage is less than 0.5%, the effect of reducing the bending tendency of the insulation covered electric wire 2 is small, and if the elongation percentage exceeds 10.0%, breakage of the metal conductor wire 21 is likely to occur. The elongation percentage of the insulation covered electric wire 2 is calculated by the formula L2 / L1, where L1 is the unit length of the insulation covered electric wire 2 before plastic stretching and L2 is the length of the portion of this unit length L1 after plastic stretching.

[0023] The inventors of the present invention have found through experiments that the bending tendency of the insulation-coated electric wire 2 can be reduced by plastically stretching the insulation-coated electric wire 2. In other words, when the conductor diameter of the metal conductor wire 21 is small, for example, 0.1 mm or less, if elongation occurs in a part of the outer circumferential surface of the metal conductor wire 21 due to tensile stress that is inevitably generated during the manufacture of the catheter cable 10, the insulation-coated electric wire 2 will bend so that the part where the elongation occurs is on the outer circumferential side of the arc. However, by plastically stretching the entire insulation-coated electric wire 2 in the longitudinal direction, the degree of variation in elongation in each part of the outer circumferential surface of the metal conductor wire 21 is reduced, and the bending tendency of the insulation-coated electric wire 2 is reduced.

[0024] Fig. 3 is an explanatory diagram showing, as a comparative example, an example of the insulation-coated electric wire 2 in which the metal conductor wire 21 is not plastically stretched in the longitudinal direction. Fig. 4(a) is an explanatory diagram showing an enlarged view of part A in Fig. 3. Fig. 4(b) is a cross-sectional view of the insulation-coated electric wire 2 at line BB in Fig. 4(a). In Fig. 4(a), the insulating layer 22 is shown by a virtual line, and the metal conductor wire 21 is shown by a solid line. In Figs. 4(a) and (b), a portion 210 in which elongation due to tensile stress has occurred in a part of the metal conductor wire 21 is shown by cross-hatching.

[0025] 4(a) and 4(b), when elongation occurs in a portion of the metal conductor wire 21 in the circumferential direction about the central axis C1, the insulation-coated electric wire 2 is curved so that the elongated portion 210 is on the outer circumferential side of the arc. In contrast, when the metal conductor wire 21 is plastically stretched in the longitudinal direction along the central axis C1, the entire metal conductor wire 21 is elongated in the circumferential direction about the central axis C1, and the degree of variation in elongation is reduced, thereby reducing the bending tendency of the insulation-coated electric wire 2.

[0026] In this embodiment, since the insulation-coated electric wire 2 is plastically stretched in the longitudinal direction at an elongation rate of 0.5% or more and 10.0% or less, it is preferable to use a material for the metal conductor wire 21 having physical properties of a tensile strength of 200 MPa or more and a breaking elongation of 25% or more in accordance with JIS C 3002. By using a metal material with such physical properties for the metal conductor wire 21, it is possible to prevent the metal conductor wire 21 from breaking even when the insulation-coated electric wire 2 is plastically stretched in the longitudinal direction.

[0027] In this embodiment, the multiple insulation covered electric wires 2 are plastically stretched by a manufacturing method for the catheter cable 10 described later. The multiple insulation covered electric wires 2 preferably have a twisting ratio of 0.5% to 5.0%. The twisting ratio K is calculated by the following formula, where P is the twist pitch of the insulation covered electric wires 2 and D is the pitch diameter of the electric wire bundle 20. Here, the pitch diameter D is the diameter of a circle (circle C2 shown in FIG. 1(b)) passing through the center points of the multiple insulation covered electric wires 2 in the outermost layer of the electric wire bundle 20 in a cross section orthogonal to the longitudinal direction of the catheter cable 10.

number

[0028] Moreover, the space factor of the electric wire bundle 20 is desirably 70% or more, which is higher than the space factor of a general multi-core cable. By twisting together and plastically stretching a plurality of insulation-coated electric wires 2 so that the space factor of the electric wire bundle 20 is 70% or more, it is possible to cause appropriate plastic elongation in the insulation-coated electric wires 2. Here, the space factor is the ratio of the total cross-sectional area of ​​the plurality of insulation-coated electric wires 2 to the area of ​​a circumscribed circle that encompasses the electric wire bundle 20 in the cross section shown in FIG. 1(b).

[0029] The elongation percentage of the insulation covered electric wire 2 can be calculated from the difference in length of the insulation covered electric wire 2 before and after plastic stretching as described above, but can also be obtained from the difference in electrical resistance per length of the insulation covered electric wire 2 before and after plastic stretching. This is because the cross-sectional area of ​​the metal conductor wire 21 decreases as the insulation covered electric wire 2 is stretched, and the electrical resistance increases.

[0030] 5 is an explanatory diagram showing a configuration example of a manufacturing apparatus 7 for manufacturing an electric wire bundle 20 by twisting a plurality of insulation-coated electric wires 2 together. The manufacturing apparatus 7 includes a twisting machine 71 that twists a plurality of insulation-coated electric wires 2 together in a spiral shape, a plurality of supply reels 70 around which a plurality of insulation-coated electric wires 2 are wound and supplied to the twisting machine 71, a take-up device 72 that takes up the electric wire bundle 20 in which the plurality of insulation-coated electric wires 2 are twisted together from the twisting machine 71, a wire drawing car 73 that is arranged between the twisting machine 71 and the take-up device 72, and a winding machine 74 that winds up the electric wire bundle 20 in which the plurality of insulation-coated electric wires 2 are plastically stretched.

[0031] The multiple insulation-coated electric wires 2 are stretched in the longitudinal direction in the plastic region by the tension generated between the take-up device 72 and the wire-drawing car 73, and are wound up in the state of a twisted electric wire bundle 20 onto a winding drum 75 by a winding machine 74. Thereafter, a bind tape 3 is wound around the outer periphery of the electric wire bundle 20, a shield conductor 4 is disposed around the outer periphery of the bind tape 3, and a sheath 5 is further formed around the outer periphery of the shield conductor 4 by extrusion molding, thereby obtaining a catheter cable 10. The elongation rate of the insulation-coated electric wires 2 can be adjusted, for example, by increasing or decreasing the rotational resistance force of the wire-drawing car 73.

[0032] In addition, the drawing car 73 may be omitted if the insulation-coated electric wires 2 can be plastically stretched at a predetermined elongation rate without disposing the drawing car 73 between the wire stranding machine 71 and the take-up device 72. Also, instead of the drawing car 73, a plurality of drawing cars for applying tension to the insulation-coated electric wires 2 supplied to the wire stranding machine 71 to plastically stretch them may be disposed between the supply reel 70 and the wire stranding machine 71.

[0033] Table 1 is a specification table showing the specifications of the catheter cable 10 according to one embodiment. [Table 1] Here, the electrical resistance of one metal conductor wire 21 per length of the electric wire bundle 20 when multiple insulation covered electric wires 2 that have not been plastically stretched are twisted together is found by multiplying the electrical resistance of the metal conductor wire 21 before plastic stretching by a coefficient corresponding to the twisting rate (1 + twisting rate (%) ÷ 100). The elongation rate (%) of the insulation covered electric wire 2 is found by dividing the electrical resistance per length of one metal conductor wire 21 when multiple insulation covered electric wires 2 that have been plastically stretched are twisted together by the electrical resistance per length of one metal conductor wire 21 when multiple insulation covered electric wires 2 that have not been plastically stretched are twisted together, subtracting 1 from the quotient, and further multiplying the result by 100.

[0034] Fig. 6 is a photograph showing a catheter cable 10 according to an embodiment having the above specifications. Fig. 6 shows a state in which the sheath 5 at the end of the catheter cable 10 has been removed, the bind tape 3 and the shield conductor 4 exposed at the end of the sheath 5 have been removed from the electric wire bundle 20, and further the twisting of the multiple insulating coated electric wires 2 at the tip of the electric wire bundle 20 has been untwisted.

[0035] 7 is a photograph showing a plurality of insulation-coated electric wires 8 that have not been plastically stretched, and a bind tape 9 wound around the outer circumference of the plurality of insulation-coated electric wires 8. The plurality of insulation-coated electric wires 8 are twisted together inside the bind tape 9 to form an electric wire bundle 80. The number of insulation-coated electric wires 8 in the electric wire bundle 80 is different from that in the above-described embodiment.

[0036] As is clear from a comparison of Figures 6 and 7, in the catheter cable 10 according to the embodiment shown in Figure 6, undulations of the multiple insulation-coated electric wires 2 are sufficiently suppressed to the extent that they do not cause problems in terminal processing.

[0037] (Effects of the embodiment) According to the embodiment described above, the bending tendency of each of the insulation-coated electric wires 2 is reduced by plastically stretching each of the insulation-coated electric wires 2 in the longitudinal direction. This improves the workability of the terminal processing of the catheter cable 10.

[0038] (Summary of the embodiment) Next, the technical ideas grasped from the above-described embodiment will be described by using the reference numerals and the like in the embodiment. However, the reference numerals and the like in the following description do not limit the components in the claims to the members and the like specifically shown in the embodiment.

[0039] [1] A multi-core cable (catheter cable 10) comprising a plurality of insulation-coated electric wires (2) having a metal conductor wire (21) and an insulating layer (22) covering the metal conductor wire (21), the plurality of insulation-coated electric wires (2) being twisted together, wherein each of the plurality of insulation-coated electric wires (2) is plastically stretched in the longitudinal direction at an elongation rate of 0.5% or more and 10.0% or less.

[0040] [2] The multi-core cable (10) according to [1] above, wherein the plurality of insulating coated electric wires (2) are a single wire having a circular cross section, and the insulating layer (22) is made of a thermosetting resin.

[0041] [3] The multi-core cable (10) according to [2] above, wherein the conductor diameter of the metal conductor wire (21) of the plurality of insulating covered electric wires (2) is 0.010 mm or more and 0.085 mm or less.

[0042] [4] The multi-core cable (10) according to the above [1], wherein the space factor of the multiple insulated electric wires (2) is 70% or more.

[0043] [5] The multi-core cable (10) according to the above [1], wherein the plurality of insulating covered electric wires (2) have a twist ratio of 0.5% or more and 5.0% or less.

[0044] [6] The multi-core cable (10) according to the above [5], wherein the number of twisted insulated-coated electric wires (2) is eight or more.

[0045] [7] The multi-core cable (10) according to the above [1], wherein the physical properties of the metal conductor wire (21) are a tensile strength of 200 MPa or more and a breaking elongation of 25% or more.

[0046] [8] The multi-core cable (10) according to the above [1], wherein the plurality of insulated electric wires (2) are signal lines for transmitting electric signals.

[0047] [9] The multi-core cable (10) described in [1] above, having a sheath (5) that collectively covers the multiple insulated electric wires (2), and the multiple insulated electric wires (2) extend from the sheath (5) at an end of the cable.

[0048]

[10] A multi-core cable assembly (100) comprising: a multi-core cable (10) described in any one of [1] to [9] above; and a terminal member (substrate 6) to which the multiple insulated-coated electric wires (2) are connected at an end of the multi-core cable (10).

[0049] Although the embodiments of the present invention have been described above, the invention according to the claims is not limited to the embodiments described above. It should be noted that not all of the combinations of features described in the embodiments are essential to the means for solving the problems of the invention.

[0050] The present invention can be modified as appropriate. For example, in the above embodiment, the terminal member to which the multiple insulation-coated electric wires 2 are connected is the substrate 6, but a connector or an electronic component such as an IC may be used as the terminal member. The multi-core cable of the present invention can be used for various purposes, not limited to the medical catheter cable 10. [Explanation of symbols]

[0051] 10...Catheter cable (multi-core cable) 100...Multi-core cable assembly 2...insulated electric wire 21...metal conductor wire 22...insulating layer 5...sheath 6... Substrate (terminal component)

Claims

1. A multi-core cable used as a catheter cable for medical devices, in which a plurality of insulated coated electric wires are twisted together to form an electric wire bundle; A terminal member on which an electrode pad is provided; A multi-core cable assembly comprising: The insulating coated electric wire is The wire has a metal conductor wire with a conductor diameter of 0.010 mm or more and 0.085 mm or less and an insulating layer covering the metal conductor wire, and is plastically stretched in the longitudinal direction at an elongation rate of 0.5% or more and 10.0% or less, the plastically stretched insulating coated electric wire is electrically connected to the electrode pad; Multi-core cable assembly.

2. the metal conductor wire is a single wire having a circular cross section, The insulating layer is made of a thermosetting resin.

2. The multi-conductor cable assembly according to claim 1.

3. The space factor of the electric wire bundle is 70% or more.

2. The multi-conductor cable assembly according to claim 1.

4. The plurality of insulating coated electric wires have a twist ratio of 0.5% or more and 5.0% or less.

2. The multi-conductor cable assembly of claim 1.

5. The number of twisted insulating coated electric wires is 8 or more.

5. The multi-conductor cable assembly according to claim 4.

6. The physical properties of the metal conductor wire are a tensile strength of 200 MPa or more and a breaking elongation of 25% or more.

2. The multi-conductor cable assembly according to claim 1.

7. The insulating coated electric wire is a signal line that transmits an electric signal.

2. The multi-conductor cable assembly according to claim 1.

8. A sheath is provided to collectively cover the plurality of insulating coated electric wires, The plurality of insulated electric wires extend from an end of the sheath.

2. The multi-conductor cable assembly according to claim 1.

9. The multi-core cable is twisted such that a specific one of the plurality of insulation-coated electric wires is not always present in the center or the outer periphery of the bundle of electric wires. A multi-conductor cable assembly according to any one of claims 1 to 8.

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