Cable and damage detector

Abstract

To provide a cable capable of reducing an occurrence of an erroneous detection while preventing an increase of man-hour in manufacturing, and to provide a damage detector using the cable.SOLUTION: A cable 1 includes: a wire bundle 10 bundling first to third wires 2-4 together; a press roll member 5 wound spirally around an outer periphery of the wire bundle 10; and a sheath 8 coating the press roll member 5. The press roll member 5 includes: a substrate 51 composed of a belt-like insulator; and a planar electrical conductor 52 arranged on one side of the substrate 51 along a longer direction of the substrate 51. The substrate 51 is wound and laminated over the outer periphery of the wire bundle 10 so that edge portions in a width direction overlap each other. A damage detector detects an occurrence of a damage when the planar electrical conductor 52 is damaged.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a cable and a damage detection device for detecting damage to the cable.

Background Art

[0002] Conventionally, there has been a device that can detect a sign of an abnormality such as a disconnection of an electric wire before an abnormality such as a disconnection of an electric wire occurs in a cable including a plurality of electric wires (see, for example, Patent Document 1).

[0003] In the first embodiment of the invention described in Patent Document 1, a detection wire is disposed at the center of the cable, and a plurality of electric wires to be a target for detecting a sign of damage are disposed around the detection wire. The detection wire has lower bend resistance than the electric wires around it, and is likely to break due to metal fatigue when bent. Then, when an inspection signal including an AC component is input to the detection wire by an abnormality detection device, and it is detected that a change in the characteristic impedance of the detection wire is equal to or greater than a reference value and a break has occurred in the detection wire conductor, it is notified to the outside that there is a sign of a disconnection occurring in the electric wire.

[0004] Further, in the second and third embodiments of the invention described in Patent Document 1, in addition to the above-described detection wire, an outer detection layer is provided so as to be able to detect damage to an electric wire caused by trauma when a sudden impact is applied from the outside of the cable. In the second embodiment, the outer detection layer is a conductive tape formed of a conductive material, and the conductive tape is spirally wound around the outer periphery of a tape layer formed by winding an insulating tape body around the outer periphery of the electric wire group. In the third embodiment, the outer detection layer is a laminated tape in which conductive coating layers are formed on both surfaces of an insulating base material, and this laminated tape is spirally wound around the outer periphery of the electric wire group. The abnormality detection device also notifies the outside when a change in the characteristic impedance of the conductive tape or the laminated tape is equal to or greater than a reference value.

Prior Art Documents

Patent Documents

[0005] Patent Document 1 Japanese Patent No. 7151754 Summary of the Invention Problems to be Solved by the Invention

[0006] When a conductive tape is spirally wound around the outer periphery of a tape layer as in the second embodiment of the invention described in Patent Document 1, during the manufacture of the cable, after winding the tape body constituting the tape layer, it is further necessary to wind the conductive tape around the outer periphery thereof, resulting in an increase in man-hours. Further, when using a laminated tape in which conductive coating layers are formed on both sides of an insulating base material as in the third embodiment of the invention described in Patent Document 1, during the use of the cable, when the cable is repeatedly bent and the laminated tape is displaced in the longitudinal direction of the cable, and a portion where the conductive coating layer on one surface side of the base material and the conductive coating layer on the other surface side of the base material come into contact is generated in a part of the longitudinal direction of the cable, even if a break occurs in any of the coating layers in this portion, it cannot be detected, resulting in a detection omission.

[0007] Therefore, an object of the present invention is to provide a cable capable of reducing the occurrence of detection omission and false detection while suppressing an increase in man-hours during manufacture, and a damage detection device using the cable. Means for Solving the Problems

[0008] The present invention aims to solve the above problems, and includes a wire bundle formed by bundling a plurality of electric wires, a pressing winding member spirally wound around the outer periphery of the wire bundle, and a sheath covering the pressing winding member. The pressing winding member has a base material made of a strip-shaped insulator and a planar conductor provided on one surface of the base material along the longitudinal direction of the base material, and is wound around the outer periphery of the wire bundle so that the end portions in the width direction of the base material overlap each other.

[0009] Further, the present invention aims to solve the above problems, and is spirally wound around the outer periphery of a wire bundle formed by bundling a plurality of electric wires, and has a base material made of a strip-shaped insulator and a planar conductor provided on one surface of the base material along the longitudinal direction of the base material. It provides a damage detection device including a pressing member and a damage detection circuit that detects the occurrence of the damage when the planar conductor is damaged.

Effect of the Invention

[0010] According to the cable and the damage detection device according to the present invention, it is possible to reduce the occurrence of detection leakage and false detection while suppressing an increase in man-hours during manufacturing.

Brief Description of the Drawings

[0011]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Figure 10

Mode for Carrying Out the Invention

[0012] [First Embodiment] FIG. 1 is a cross-sectional view of a cable 1 according to a first embodiment of the present invention. The cable 1 includes a wire bundle 10 formed by bundling a plurality of electric wires 2 to 4, a pressing winding member 5 spirally wound around the outer periphery of the wire bundle 10, a linear conductor 6 and an inclusion 7 covered by the pressing winding member 5 together with the wire bundle 10, and a sheath 8 covering the pressing winding member 5.

[0013] In the present embodiment, among the plurality of electric wires 2 to 4, the first electric wire 2 and the second electric wire 3 are power supply lines for supplying an operating power source to a target device. The third electric wire 4 is a multi-core electric wire in which a pair of signal lines 41 and 42 are covered by an inner sheath 43. Also, in the present embodiment, one end of each of the first to third electric wires 2 to 4 of the cable 1 is connected to a spring lower member of the vehicle, and the other end of each of the first to third electric wires 2 to 4 is connected to a control device disposed on the vehicle body side, which is a spring upper member. The target device below the spring to which power is supplied by the first electric wire 2 and the second electric wire 3 is, for example, an electric parking brake device that locks the wheels when the vehicle stops. The pair of signal lines 41 and 42 of the third electric wire 4 are connected to, for example, a wheel speed sensor that detects the rotational speed of the wheel, and transmit the output signal of the wheel speed sensor. The cable 1 has a part in the longitudinal direction repeatedly bent as the suspension spring expands and contracts during the running of the vehicle.

[0014] The first electric wire 2 is an insulated coated electric wire in which a conductor 21 is coated with an insulator 22. The second electric wire 3 is an insulated coated electric wire in which a conductor 31 is coated with an insulator 32. The conductors 21 and 31 are stranded wires formed by stranding a plurality of strands 210 and 310 made of a highly conductive metal such as copper. The pair of signal wires 41 and 42 of the third electric wire 4 are each an insulated coated electric wire in which a conductor 411 and 421 are coated with insulators 412 and 422. The conductors 411 and 421 are stranded wires formed by stranding a plurality of strands 410 and 420 made of a highly conductive metal such as copper. The insulators 22 and 32 of the first and second electric wires 2 and 3, and the insulators 412 and 422 of the pair of signal wires 41 and 42 of the third electric wire 4 are made of, for example, a fluororesin.

[0015] The signal wires 41 and 42 of the third electric wire 4 have an outer diameter smaller than those of the first electric wire 2 and the second electric wire 3, and the outer diameter of each of the signal wires 41 and 42 is not more than half of the outer diameter of the first electric wire 2 and the second electric wire 3. The signal wires 41 and 42 of the third electric wire 4 are one aspect of the small-diameter electric wire of the present invention, and the first electric wire 2 and the second electric wire 3 are one aspect of the large-diameter electric wire of the present invention. In the present embodiment, the wire bundle 10 is configured to have one multi-core electric wire (the third electric wire 4), but the plurality of electric wires constituting the wire bundle may include a plurality of multi-core electric wires. Further, the plurality of electric wires constituting the wire bundle may not include a multi-core electric wire.

[0016] FIG. 2 is an explanatory view showing the configuration of the wire bundle 10 and the pressing member 5. In FIG. 2, the illustration of the inclusion 7 and the sheath 8 is omitted, and a state of viewing the wire bundle 10 and the pressing member 5 from the radial direction of the cable 1 is shown. Further, in FIG. 2, the contour of the inner sheath 43 of the third electric wire 4 is shown by a virtual line (a two-dot chain line) in a part of the longitudinal direction of the wire bundle 10, and the pair of signal wires 41 and 42 are shown by solid lines.

[0017] As shown in FIG. 2, the first to third electric wires 2 to 4 are twisted together, and the pair of signal wires 41 and 42 of the third electric wire 4 are further twisted inside the inner sheath 43 to form a pair-twisted wire. In FIG. 1, the twisting direction of the first to third electric wires 2 to 4 is indicated by an arrow A 10It is shown by [[ID=]], and the twisting direction of a pair of signal lines 41 and 42 in the multi-core electric wire 4 is indicated by an arrow A4. As shown in FIGS. 1 and 2, in the present embodiment, the twisting direction of the first to third electric wires 2 to 4 as viewed in the longitudinal direction of the cable 1 is the same as the twisting direction of the pair of signal lines 41 and 42.

[0018] Also, in FIG. 1, the twisting directions of a plurality of strands 210 in the conductor 21 of the first electric wire 2, the twisting directions of a plurality of strands 310 in the conductor 31 of the second electric wire 3, and the twisting directions of a plurality of strands 410 and 420 of a pair of signal lines 41 and 42 in the multi-core electric wire 4 are respectively indicated by arrows A 21 , A 31 , A 41 , A 42 . The twisting directions of these strands 210, 310, 410, and 420 are the same as the twisting directions of the first to third electric wires 2 to 4 and the twisting direction of the pair of signal lines 41 and 42. As a result, the twists of the first to third electric wires 2 to 4 are less likely to unwind.

[0019] The inclusion 7 is made of a fibrous body such as aramid fiber or Kevlar (registered trademark), and is disposed between the first to third electric wires 2 to 4 and the pressing member 5. Due to this inclusion 7, the shape of the pressing member 5 in a cross section perpendicular to the longitudinal direction of the cable 1 is close to a circular shape. That is, the shape of the pressing member 5 in a cross section perpendicular to the longitudinal direction of the electric wire bundle 10 is circularized by the inclusion 7. As a result, the cable 1 can be flexibly bent in all directions.

[0020] The outer diameter of the first electric wire 2 is the same as the outer diameter of the second electric wire 3. Also, the outer diameter of the third electric wire 4 is about the same as the outer diameter of the first electric wire 2 and the outer diameter of the second electric wire 3. Specifically, the outer diameter of the third electric wire 4 is 95% or more and 105% or less of the outer diameter of the first electric wire 2 and the second electric wire 3. This dimensional relationship contributes to circularizing the shape of the pressing member 5 in a cross section perpendicular to the longitudinal direction of the electric wire bundle 10.

[0021] In the example shown in FIG. 1, a part of the outer peripheral surfaces 2a, 3a, and 4a of the first to third electric wires 2 to 4 are in contact with each other, and a part of the outer peripheral surfaces 2a, 3a, and 4a of the first to third electric wires 2 to 4 are in contact with the pressing member 5. However, the outer peripheral surfaces 2a, 3a, and 4a of the first to third electric wires 2 to 4 do not necessarily have to be in contact with each other, and the outer peripheral surfaces 2a, 3a, and 4a of the first to third electric wires 2 to 4 do not necessarily have to be in contact with the pressing member 5.

[0022] FIG. 3 is a perspective view showing the pressing member 5 alone. FIG. 4 is a cross-sectional view showing the pressing member 5 in a spirally wound state. The pressing member 5 includes a base material 51 made of a flexible belt-like insulator, and a planar conductor 52 provided on one surface 51a of the base material 51 along the longitudinal direction of the base material 51. A conductor is not provided on the other surface 51b of the base material 51 corresponding to the back side of one surface 51a of the base material 51. That is, the planar conductor 52 is provided only on one surface 51a of the base material 51. Since the planar conductor 52 is integrated with the base material 51, the pitch in the longitudinal direction of the cable 1 of the base material 51 and the pitch in the longitudinal direction of the cable 1 of the planar conductor 52 are the same when the pressing member 5 is wound spirally around the cable 1.

[0023] In the present embodiment, the planar conductor 52 is formed by vapor deposition on one surface 51a of the base material 51. The base material 51 is a belt-like body made of, for example, a resin such as non-woven fabric, paper, or polyester. The main component of the planar conductor 52 is made of a highly conductive metal such as copper, silver, or aluminum. By providing the planar conductor 52 on one surface 51a of the base material 51, the strength of the planar conductor 52 is ensured, and it is prevented that the planar conductor 52 is likely to break excessively.

[0024] In the present embodiment, the thickness of the planar conductor 52 is thinner than that of the base material 51. However, the present invention is not limited to this, and the planar conductor 52 may be thicker than the base material 51. If the thickness of the planar conductor 52 is thinner than that of the base material 51, it is possible to sensitively detect the occurrence of trauma caused by flying stones or the like and the wear of the sheath 8. Further, if the planar conductor 52 is thicker than the base material 51, it becomes easier to prevent the planar conductor 52 from being disconnected due to friction with the sheath 8.

[0025] In FIG. 3, the width of the base material 51 in the short side direction of the pressing member 5 is indicated by W1, and the width of the planar conductor 52 is indicated by W2. W2 is narrower than W1, and the planar conductor 52 is formed in a range excluding both end portions in the width direction of the base material 51. The desirable range of W2 with respect to W1 depends on the thickness of the planar conductor 52 and the strength of the base material 51, but is, for example, 10% or more and 30% or less. However, the present invention is not limited to this, and the planar conductor 52 may be formed over the entire surface 51a of one side of the base material 51.

[0026] The pressing member 5 is wound around the outer periphery of the wire bundle 10 so that the end portions in the width direction of the base material 51 overlap in the radial direction of the cable 1. In the present embodiment, the end portions in the width direction of the base material 51 overlap and are in contact with each other. More specifically, one surface 51a of the end portion on one side in the width direction of the base material 51 and the other surface 51b of the end portion on the other side in the width direction of the base material 51 overlap and are in contact with each other in the thickness direction of the base material 51. In the longitudinal direction of the cable 1 (the left - right direction in FIG. 4), the ratio of the overlapping length L2 at the end portion in the width direction of the base material 51 to the length L1 of the base material 51 for one turn is, for example, 10% or more and 40% or less. In the overlapping portion of the pressing member 5, a part of the other surface 51b of the base material 51 may overlap with the planar conductor 52. In the present invention, in the longitudinal direction of the cable 1, there is no portion where the planar conductors 52 overlap while being in contact with each other. However, in the present invention, in the longitudinal direction of the cable 1, there may be a portion where the planar conductors 52 overlap without contacting each other due to the presence of the base material 51.

[0027] In FIG. 2, the planar conductor 52 of the holding winding member 5 is shown in gray. As shown in FIGS. 1 and 2, the holding winding member 5 is spirally wound around the outer periphery of the wire bundle 10 such that one surface 51a of the base material 51 provided with the planar conductor 52 faces outward, and the first to third wires 2 to 4 are pressed toward the center of the cable 1 by the other surface 51b of the base material 51. The planar conductor 52 is in contact with the sheath 8 outside the base material 51.

[0028] The sheath 8 is made of a urethane resin such as thermoplastic polyurethane, for example, and is extrusion-molded on the outer periphery of the holding winding member 5. The holding winding member 5 covers the entire circumference of the wire bundle 10 in a cross-sectional view. This prevents the liquid thermoplastic resin forming the sheath 8 from entering between the first to third wires 2 to 4 during the molding of the sheath 8.

[0029] The cable 1 configured as described above may be damaged, for example, by being hit by flying stones or the like during the running of a vehicle, or the sheath 8 may be severely worn due to friction with the outside. In the present embodiment, when the cable 1 is damaged due to such trauma or wear, the occurrence of the damage is detected by a damage detection device described below.

[0030] FIG. 5(a) is a circuit diagram showing a configuration example of a damage detection device 11 for detecting damage to the cable 1. FIG. 5(b) is a cross-sectional view showing a configuration example of the linear conductor 6. The damage detection device 11 includes the holding winding member 5 and the linear conductor 6 as components, and is configured to have a damage detection circuit 110 that electrically detects the occurrence of damage in the cable 1.

[0031] As shown in FIG. 5(b), the linear conductor 6 is an insulated wire having a conductor 61 and an insulator 62 covering the conductor 61. In the example shown in FIG. 5(b), the conductor 61 is a stranded wire formed by twisting a plurality of strands 610, but it is not limited thereto, and the conductor 61 may be a single wire. Further, the insulator 62 may be omitted, and the linear conductor 6 may be an uncoated wire (bare wire).

[0032] The linear conductor 6 is disposed inside the pressing member 5 together with the first to third electric wires 2 to 4, and the conductor 61 of the linear conductor 6 is electrically connected to the planar conductor 52 of the pressing member 5 at one terminal portion in the longitudinal direction of the cable 1. In the present embodiment, this terminal portion corresponds to the end portion below the spring of the vehicle. In the example shown in FIG. 5(a), the case where the planar conductor 52 and the linear conductor 6 are connected by the termination resistor Rt is shown, but the present invention is not limited thereto, and the conductor 61 of the linear conductor 6 may be directly connected to the planar conductor 52 of the pressing member 5 to short-circuit them.

[0033] The linear conductor 6 has lower bending durability than the first to third electric wires 2 to 4, and when the cable 1 is repeatedly bent, it breaks before any of the first to third electric wires 2 to 4 breaks. Further, the conductor cross-sectional area of the conductor 61 of the linear conductor 6 is smaller than the conductor cross-sectional area of the conductor 21 of the first electric wire 2, the conductor cross-sectional area of the conductor 31 of the second electric wire 3, and the conductor cross-sectional areas of the signal lines 41 and 42 of the third electric wire 4, i.e., the conductor 411 and 421.

[0034] In the present embodiment, as shown in FIG. 1, the linear conductor 6 is disposed between the first electric wire 2 and the second electric wire 3 and the pressing member 5. However, the arrangement position of the linear conductor 6 is not limited thereto, and for example, the linear conductor 6 may be disposed at the center of the cable 1 surrounded by the first to third electric wires 2 to 4. The linear conductor 6 may be separated from the wire bundle 10 as shown in FIG. 1, or may be in contact with the wire bundle 10.

[0035] The damage detection circuit 110 is provided on the side opposite to the side where the planar conductor 52 of the pressing member 5 and the conductor 61 of the linear conductor 6 are electrically connected in the longitudinal direction of the cable 1, and detects the occurrence of the damage when either the planar conductor 52 or the linear conductor 6 is damaged. Further, when the damage detection circuit 110 detects the occurrence of the damage, it outputs a damage detection signal for notifying the occurrence of the damage. When this damage detection signal is output, the occurrence of the damage to the cable 1 is notified to the driver, for example, by lighting a lamp on the instrument panel of the vehicle.

[0036] In the circuit configuration example of the damage detection circuit 110 shown in Fig. 5(a), a shunt resistor Rs, a planar conductor 52, a terminal resistor Rt, and a linear conductor 6 are connected in series between the + side and the - side of the DC power supply V. The damage detection circuit 110 also has first and second reference resistors Ra and Rb connected in series between the + side and the - side of the DC power supply V, and a comparator C. A reference voltage Vref, which is a voltage obtained by resistively dividing the voltage of the DC power supply V with the first and second reference resistors Ra and Rb, and a detection voltage Vd, which is the voltage on the planar conductor 52 side of the shunt resistor Rs, are input to the comparator C.

[0037] When no disconnection occurs in either the planar conductor 52 or the conductor 61 of the linear conductor 6 and a predetermined current flows through the series circuit composed of the shunt resistor Rs, the planar conductor 52, the terminal resistor Rt, and the linear conductor 6, a voltage drop corresponding to the magnitude of the current occurs in the shunt resistor Rs, and the detection voltage Vd becomes lower than the voltage of the DC power supply V. On the other hand, when either the planar conductor 52 or the conductor 61 of the linear conductor 6 is disconnected, no current flows through this series circuit, and the detection voltage Vd becomes equal to the voltage of the DC power supply V.

[0038] The reference voltage Vref is adjusted to be a value between the detection voltage Vd when no disconnection occurs in the planar conductor 52 and the conductor 61 of the linear conductor 6 and the detection voltage Vd when a disconnection occurs in either the planar conductor 52 or the conductor 61 of the linear conductor 6. When a disconnection occurs in either the planar conductor 52 or the conductor 61 of the linear conductor 6, the output voltage Vout of the comparator C changes. The output voltage Vout of the comparator C is output from the damage detection circuit 110 as a damage detection signal indicating that damage has occurred in the cable 1.

[0039] [Comparative Example] Fig. 6 is a cross-sectional view showing a cable 100 according to the comparative example. In Fig. 6, components common to the components of the cable 1 according to the first embodiment are denoted by the same reference numerals as those in Fig. 1 and the like, and redundant descriptions are omitted.

[0040] In cable 100, the shape of the holding member 5 in the cross-section of the cable 100 is a triangular shape with rounded corners. That is, at each corner of this triangular shape, the base material 51 of the holding member 5 curves along the outer peripheral surfaces 2a, 3a, and 4a of the first electric wire 2, the second electric wire 3, and the third electric wire 4 with the curvature of these outer peripheral surfaces 2a, 3a, 4a.

[0041] In this cable 100, compared with the cable 1 according to the first embodiment, the planar conductor 52 of the holding member 5 is subjected to stress due to being bent with a large curvature, and this stress makes the planar conductor 52 likely to break, and false detection of damage is likely to occur. On the other hand, in the cable 1 according to the first embodiment, the shape of the holding member 5 in the cross-section perpendicular to the longitudinal direction of the wire bundle 10 is circularized, and the curvature of the base material 51 is smaller than the curvature of the outer peripheral surfaces 2a, 3a, 4a of the first to third electric wires 2 to 4, so stress due to bending is less likely to occur in the planar conductor 52, and the occurrence of false detection can be suppressed.

[0042] (Effect of the First Embodiment) According to the first embodiment described above, the holding member 5 has the base material 51 and the planar conductor 52, and when the planar conductor 52 is disconnected, the occurrence of the disconnection is detected by the damage detection circuit 110. Therefore, for example, compared with the case where a holding tape and a conductive tape are separately wound around the outer periphery of the wire bundle 10, it is possible to reduce the occurrence of false detection while suppressing an increase in man-hours during manufacturing. Also, since the planar conductor 52 is provided only on one surface 51a of the base material 51, the planar conductors 52 of different turns of the spirally wound holding member 5 do not come into contact with each other, and the occurrence of detection omission can be suppressed. Further, during the molding of the sheath 8, it is possible to suppress the planar conductor 52 from deviating from the desired position with respect to the base material 51 by the liquid thermoplastic resin forming the sheath 8.

[0043] Also, according to the first embodiment, since the linear conductor 6 has lower bending durability than the first to third electric wires 2 to 4, even when the linear conductor 6 is disconnected, the occurrence of the disconnection is detected by the damage detection circuit 110. Therefore, in addition to sudden trauma caused by the impact of flying stones or the like and the wear of the sheath 8, it is possible to detect the sign of disconnection of the first to third electric wires 2 to 4 due to metal fatigue caused by repeated bending by the disconnection of the linear conductor 6.

[0044] Also, according to the first embodiment, since the planar conductor 52 is provided on one surface 51a which is the surface on the sheath 8 side of the base material 51, it is possible to prevent the disconnection of the planar conductor 52 due to wear caused by contact with the first to third electric wires 2 to 4.

[0045] [Modification of the First Embodiment] FIG. 7(a) is a perspective view showing the pressing and winding member 5A according to the modification of the first embodiment alone. FIG. 7(b) is a cross-sectional view of the pressing and winding member 5A in a cross-section perpendicular to the longitudinal direction of the pressing and winding member 5A. This pressing and winding member 5A is spirally wound around the outer periphery of the wire bundle 10 with one surface 51a of the base material 51 facing outward, similarly to the pressing and winding member 5 according to the first embodiment.

[0046] In the first embodiment, the case where the planar conductor 52 is formed by vapor deposition on one surface 51a of the base material 51 has been described. The pressing member 5A according to the modification has the same base material 51 as in the first embodiment and a planar conductor 53 provided by adhering to one surface 51a of the base material 51. The planar conductor 53 is a metal foil made of a highly conductive metal such as copper, silver, or aluminum, for example. An adhesive layer 54 made of an adhesive is interposed between the base material 51 and the planar conductor 53. That is, the planar conductor 53 is fixed to the base material 51 by an adhesive. Note that the planar conductor 53 may be thicker or thinner than the base material 51. The adhesive preferably has a melting point higher than the temperature of the liquid thermoplastic resin that forms the sheath 8 during the molding of the sheath 8. Thereby, it is possible to suppress the softening or melting of the adhesive during the molding of the sheath 8, and it is possible to further suppress the displacement of the planar conductor 52 from the desired position with respect to the base material 51.

[0047] Even when the pressing member 5A according to this modification is used, the same effects as in the first embodiment can be obtained.

[0048] [Second Embodiment] FIG. 8 is a cross-sectional view showing the cable 1B according to the second embodiment of the present invention. In the first embodiment, the case where the pressing member 5 is wound around the outer periphery of the wire bundle 10 so that one surface 5a of the base material 51 on which the planar conductor 52 is formed faces the outside (sheath 8 side) has been described. However, in the second embodiment, the pressing member 5 is wound around the outer periphery of the wire bundle 10 so that one surface 5a of the base material 51 on which the planar conductor 52 is formed faces the inside (wire bundle 10 side).

[0049] An inclusion 7 is disposed between the planar conductor 52 and the first to third electric wires 2 to 4, and even when the cable 1B is bent, rubbing between the planar conductor 52 and the first to third electric wires 2 to 4 is suppressed. Further, due to the inclusion 7, the shape of the pressing member 5 in a cross section perpendicular to the longitudinal direction of the wire bundle 10 is circularized. Further, the occurrence of damage in the cable 1B is detected by the damage detection circuit 110 described in the first embodiment. Depending on the strength of the planar conductor 52, a part of the inclusion 7 may be deleted and the planar conductor 52 may be brought into contact with the first to third electric wires 2 to 4. Thereby, the cable 1B can be made thinner.

[0050] Note that the planar conductor 52 is formed, for example, by vapor deposition on one surface 5a of the base material 51. However, using the pressing member 5A according to the modification described with reference to FIGS. 7(a) and 7(b), the pressing member 5A may be wound around the outer periphery of the wire bundle 10 such that one surface 5a of the base material 51 faces inward. By winding the pressing member 5A around the outer periphery of the wire bundle 10 such that one surface 5a of the base material 51 faces inward, it is possible to suppress the adhesion of the planar conductor 53 of the pressing member 5A from being peeled off by the pressure of the resin when the sheath 8 is extrusion-molded.

[0051] Also with the cable 1B according to this second embodiment, as in the first embodiment, it is possible to reduce the occurrence of detection omission and false detection while suppressing an increase in the number of man-hours during manufacturing.

[0052] [Third Embodiment] FIG. 9(a) is a cross-sectional view showing a cable 1C according to the third embodiment of the present invention. The cable 1C according to the third embodiment is obtained by adding a fragile wire 9, which has lower bending durability and is more likely to break than the first to third electric wires 2 to 4, to the cable 1 according to the first embodiment. The fragile wire 9 is disposed at the center of the cable 1C surrounded by the first to third electric wires 2 to 4 and extends in the longitudinal direction of the cable 1C.

[0053] FIG. 9(b) is a cross-sectional view of the weak wire 9. The weak wire 9 is an insulated wire having a conductor 91 and an insulator 92 covering the conductor 91. The conductor 91 is a stranded wire formed by twisting a plurality of strands 910, but is not limited thereto, and the conductor 91 may be a single wire. Further, the insulator 92 may be omitted and the weak wire 9 may be an uncoated wire (bare wire).

[0054] The weak wire 9 is used to detect a sign before any of the first to third wires 2 to 4 is disconnected due to the repeated bending of the cable 1C. That is, in the present embodiment, the occurrence of sudden trauma such as a flying stone or the occurrence of damage such as wear of the sheath 8 is detected by the disconnection of the planar conductor 52 of the pressing member 5, and the sign of disconnection due to metal fatigue of the conductors 21, 31, 411, 421 of the first to third wires 2 to 4 is detected by the disconnection of the weak wire 9. The thickness of the planar conductor 52 of the pressing member 5 is formed thinner than the conductor diameter of the conductor 91 of the weak wire 9. Thereby, the wear and occurrence of trauma of the sheath 8 can be detected sensitively.

[0055] In the cable 1C, instead of the pressing member 5, the pressing member 5A shown in FIGS. 7(a) and 7(b) in which the planar conductor 53 is adhered to one surface 51a of the base material 51 may be used. In this case, the thickness of the planar conductor 53 of the pressing member 5A is formed thinner than the conductor diameter of the conductor 91 of the weak wire 9.

[0056] FIG. 10 is a circuit diagram showing a configuration example of the damage detection device 12 according to the third embodiment. The damage detection device 12 includes the pressing member 5, the weak wire 9, and the linear conductor 6 of the cable 1C as components, and includes a damage detection circuit 120. The damage detection circuit 120 has a first circuit portion 121 for detecting the disconnection of the planar conductor 52 of the pressing member 5 and a second circuit portion 122 for detecting the disconnection of the conductor 91 of the weak wire 9.

[0057] The first circuit portion 121 of the damage detection circuit 120 includes reference resistors Ra1 and Rb1 that generate a reference voltage Vref1 by resistively dividing the voltage of the DC power supply V, a shunt resistor Rs1, and a comparator C1 that compares a detection voltage Vd1, which is the voltage on the planar conductor 52 side of the shunt resistor Rs1, with the reference voltage Vref1. When a disconnection occurs in the planar conductor 52, the output voltage Vout1 of the comparator C1 changes. The planar conductor 52 of the pressing member 5 and the linear conductor 6 are electrically connected by a first termination resistor Rt1 at the longitudinal terminal portion of the cable 1C, which is the end portion on the side opposite to the damage detection circuit 120.

[0058] The second circuit portion 121 of the damage detection circuit 120 includes reference resistors Ra2 and Rb2 that generate a reference voltage Vref2 by resistively dividing the voltage of the DC power supply V, a shunt resistor Rs2, and a comparator C2 that compares a detection voltage Vd2, which is the voltage on the vulnerable wire 9 side of the shunt resistor Rs2, with the reference voltage Vref2. When a disconnection occurs in the conductor 91 of the vulnerable wire 9, the output voltage Vout2 of the comparator C2 changes. The conductor 91 of the vulnerable wire 9 and the linear conductor 6 are electrically connected by a second termination resistor Rt2 at the longitudinal terminal portion of the cable 1C, which is the end portion on the side opposite to the damage detection circuit 120.

[0059] The output voltage Vout1 of the comparator C1 of the first circuit portion 121 is output from the damage detection circuit 120 as a damage detection signal indicating that damage has occurred in the cable 1C. The output voltage Vout2 of the comparator C2 of the second circuit portion 122 is output from the damage detection circuit 120 as a sign detection signal indicating that there is a sign of disconnection in the first to third electric wires 2 to 4 of the cable 1C. When the damage detection signal or the sign detection signal is output, the driver is notified, for example, by the lighting of a lamp on the instrument panel of the vehicle.

[0060] According to this third embodiment, it is possible to reduce the occurrence of detection leakage and false detection while suppressing an increase in man-hours during manufacturing, and it is possible to detect a sign of disconnection due to metal fatigue of the conductors 21, 31, 411, 421 of the first to third electric wires 2 to 4 by the weak line 9. In the first embodiment, the linear conductor 6 has lower bending durability than the first to third electric wires 2 to 4. However, in the third embodiment, since a sign of disconnection of the first to third electric wires 2 to 4 can be detected by the weak line 9, the bending durability of the linear conductor 6 does not necessarily have to be lower than that of the first to third electric wires 2 to 4. Further, the weak line 9 does not necessarily have to be disposed at the center of the cable 1C, and the weak line 9 may be disposed between the first to third electric wires 2 to 4 and the pressing member 5. In this case, the weak line 9 is twisted together with the first to third electric wires 2 to 4 and the linear conductor 6.

[0061] (Summary of Embodiments) Next, the technical idea grasped from each of the above-described embodiments and modified examples will be described by referring to the reference numerals and the like in the embodiments and modified examples. However, each reference numeral in the following description is not limited to the members and the like that specifically show the components in the claims in the embodiments.

[0062] [1] A cable (1, 1B, 1C) comprising a wire bundle (10) formed by bundling a plurality of electric wires (2 to 4), a pressing member (5, 5A) spirally wound around the outer periphery of the wire bundle (10), and a sheath (8) covering the pressing member (5, 5A), wherein the pressing member (5, 5A) has a base material (51) made of a strip-shaped insulator and a planar conductor (52, 53) provided on one surface (51a) of the base material (51) along the longitudinal direction of the base material (51), and the outer periphery of the wire bundle (10) is wound around so that the end portions in the width direction of the base material (51) overlap each other.

[0063] [2] The cable (1, 1C) according to [1] above, wherein the planar conductor (52, 53) is provided on the surface (one surface 51a) of the base material (51) on the sheath (8) side.

[0064] [3] The pressing and winding member (5, 5A) is the cable (1, 1B, 1C) according to [1] or [2] above, wherein the width (W2) of the planar conductor (52) in the width direction of the base material (51) is narrower than the width (W1) of the base material (51), and the end portions of the base material (51) in the width direction overlap and contact each other.

[0065] [4] The planar conductor (52) is the cable (1, 1B, 1C) according to any one of [1] to [3] above, which is formed by vapor deposition on the base material (51).

[0066] [5] The planar conductor (53) is the cable (1) according to any one of [1] to [3] above, which is adhered to the base material (51).

[0067] [6] The wire bundle (10) is formed by bundling at least three wires (2 to 4), and an intervening object (7) is disposed between the pressing and winding member (5, 5A) and the at least three wires (2 to 4). The shape of the pressing and winding member (5, 5A) in a cross section perpendicular to the longitudinal direction of the wire bundle (10) is circularized by the intervening object (7). The cable (1, 1B, 1C) according to [1] above.

[0068] [7] The wire bundle (10) includes, as the plurality of wires, a plurality of large-diameter wires (first and second wires 2, 3) and at least one multi-core wire (4) in which a plurality of small-diameter wires (signal lines 41, 42) having an outer diameter smaller than that of the plurality of large-diameter wires (2, 3) are collectively covered by a sheath (inner sheath 43). The outer diameter of each of the plurality of large-diameter wires (2, 3) is approximately the same as the outer diameter of the at least one multi-core wire (4). The cable (1, 1B, 1C) according to [6] above.

[0069] [8] The cable (1, 1B, 1C) according to [1] above, further comprising a linear conductor (6) electrically connected to the planar conductor (52, 53) at one end in the longitudinal direction of the cable (in the longitudinal direction of the cables 1, 1B, 1C), and the linear conductor (6) being arranged inside the pressing member (5, 5A) together with the plurality of electric wires (2 to 4).

[0070] [9] The cable (1, 1B) according to [8] above, wherein the linear conductor (6) has lower bending durability than the plurality of electric wires (2 to 4).

[0071]

[10] A pressing member (5, 5A) having a base material (51) made of a strip-shaped insulator wound spirally around the outer periphery of an electric wire bundle (10) formed by bundling a plurality of electric wires (2 to 4), and planar conductors (52, 53) provided on one surface (51a) of the base material (51) along the longitudinal direction of the base material (51), and a damage detection circuit (110, 120) for detecting the occurrence of damage when the planar conductors (52, 53) are damaged.

[0072] The embodiments and modifications of the present invention have been described above. However, the above embodiments and modifications do not limit the invention according to the claims. Also, it should be noted that not all combinations of the features described in the embodiments and modifications are essential means for solving the problems of the invention. Further, the present invention can be appropriately modified and implemented without departing from its gist, and for example, it can be modified and implemented as follows.

[0073] In the above embodiment, the case where the third electric wire 4, which is a multi-core electric wire, has a plurality of signal lines 41, 42 as small-diameter electric wires has been described. However, the plurality of small-diameter electric wires constituting the multi-core electric wire may be used as power supply lines for supplying operating power to the target device. Examples of the target device include an active suspension device with variable damping force and a pneumatic pressure detection device for detecting the pneumatic pressure of a tire.

[0074] In the above-described embodiment, the first and second electric wires 2 and 3 are used as power supply wires for supplying operating power to the electric parking brake device, and the signal lines 41 and 42 of the third electric wire 4 are used for transmitting the output signals of the wheel speed sensors. However, the uses of the first to third electric wires 2 to 4 are not limited to this. For example, the first electric wire 2 and the second electric wire 3 may be used as power supply wires for supplying operating power to an electric brake device that brakes the rotation of the wheels during vehicle travel, and the signal lines 41 and 42 of the third electric wire 4 may be used for transmitting control signals for controlling the electric brake device.

[0075] In the above-described embodiment, the case where three electric wires (the first to third electric wires 2 to 4) are bundled to form the wire harness 10 has been described. However, the present invention is not limited to this, and the number of electric wires may be two or four or more.

[0076] In the above-described embodiment, the case where a direct current is passed through the planar conductor 52 to detect a disconnection of the planar conductor 52 has been described. However, the present invention is not limited to this. For example, a pulsed signal may be input to the planar conductor 52, and whether this signal returns via the linear conductor 6 may be confirmed to detect a disconnection of the planar conductor 52. Alternatively, a signal including an alternating current component may be input to the planar conductor 52, and a response signal may be detected by the reflection method or the transmission method to detect a disconnection of the planar conductor 52.

[0077] In the above-described embodiment, the case where the cable 1 is mounted on a vehicle has been described. However, the present invention is not limited to this, and the cable 1 may be used in industrial machines such as robots and machine tools.

Explanation of Reference Numerals

[0078] 1, 1B, 1C... Cable 10... Wire harness 11, 12... Damage detection device 110, 120... Damage detection circuit 2, 3... First and second electric wires (large-diameter electric wires) 4... Third electric wire 41, 42... Signal lines (small-diameter electric wires) 43... Inner sheath 5, 5A... Pressing member 51... Base material 51a…One side 52, 53…Planar conductor 6…Linear conductor 7…Inclusion 8…Sheath 9…Weak line

Claims

1. A cable bundle formed by bundling a plurality of electric wires, a pressing winding member spirally wound around the outer periphery of the cable bundle, and a sheath covering the pressing winding member, wherein the pressing winding member has a base material made of a strip-shaped insulator and a planar conductor provided on one surface of the base material along the longitudinal direction of the base material, and is wound around the outer periphery of the cable bundle so that the end portions in the width direction of the base material overlap each other. Cable.

2. The cable according to claim 1, wherein the planar conductor is provided on the surface of the base material on the sheath side. The cable according to claim 1.

3. The cable according to claim 1 or 2, wherein the width of the planar conductor in the width direction of the base material is narrower than the width of the base material, and the end portions in the width direction of the base material overlap and contact each other. The cable according to claim 1 or 2.

4. The cable according to any one of claims 1 to 3, wherein the planar conductor is formed by vapor deposition on the base material. The cable according to any one of claims 1 to 3.

5. The cable according to any one of claims 1 to 3, wherein the planar conductor is adhered to the base material. The cable according to any one of claims 1 to 3.

6. The cable bundle is formed by bundling at least three electric wires, an intervening object is disposed between the pressing winding member and the at least three electric wires, and the shape of the pressing winding member in a cross section perpendicular to the longitudinal direction of the cable bundle is circularized by the intervening object. The cable according to claim 1.

7. The cable according to claim 6, wherein the cable bundle includes, as the plurality of electric wires, a plurality of large-diameter electric wires and at least one multi-core electric wire in which a plurality of small-diameter electric wires having an outer diameter smaller than that of the plurality of large-diameter electric wires are collectively covered by a sheath, and the outer diameter of each of the plurality of large-diameter electric wires is approximately the same as the outer diameter of the at least one multi-core electric wire. The cable according to claim 6.

8. The cable according to claim 1, further comprising a linear conductor electrically connected to the planar conductor at one terminal portion in the longitudinal direction of the cable, wherein the linear conductor is disposed inside the pressing winding member together with the plurality of electric wires. The cable according to claim 1.

9. The cable according to claim 8, wherein the linear conductor has lower bending durability than the plurality of electric wires. The cable according to claim 8.

10. A pressing winding member spirally wound around the outer periphery of a cable bundle formed by bundling a plurality of electric wires, the pressing winding member having a base material made of a strip-shaped insulator and a planar conductor provided on one surface of the base material along the longitudinal direction of the base material, and a damage detection circuit for detecting the occurrence of damage when the planar conductor is damaged. Damage detection device provided with.

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