Cables and harnesses

Abstract

To improve flexibility of a cable including an interposition.SOLUTION: A cable 1 comprises: a stranded wire aggregate 2 formed by stranding a power source wire 10, a signal wire 20 and interpositions 31, 32; a tape member 3 wound around the stranded wire aggregate 2; and a sheath 4 covering the periphery of the tape member 3. Each of the interpositions 31, 32 is constituted by stranding a plurality of element wires, and is brought into contact with the outer peripheral surface of the power source wire 10, the outer peripheral surface of the signal wire 20, and the inner peripheral surface of the tape member 3.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to cables and harnesses.

Background Art

[0002] A harness (sometimes called a "wire harness") in which a connector is provided at at least one end of a cable (composite cable) including a plurality of electric wires is known. One of the conventional cables constituting the harness includes a plurality of electric wires and an intervening member, a tape member, and a sheath. The plurality of electric wires and the intervening member are collectively twisted to form a twisted wire assembly. The tape member is wound around the twisted wire assembly, and the sheath covers the tape member (see, for example, Patent Document 1).

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] Generally, a cable including an intervening member is less flexible than a cable not including an intervening member. Therefore, it is required to suppress a decrease in the flexibility of the cable due to the inclusion of the intervening member.

[0005] An object of the present invention is to suppress a decrease in the flexibility of a cable including an intervening member.

Means for Solving the Problems

[0006] One embodiment of the cable comprises a stranded wire assembly formed by twisting together multiple electric wires and multiple intervening elements, a tape member wrapped around the stranded wire assembly, and a sheath covering the tape member. Each of the intervening elements is composed of multiple strands of twisted wires and is in contact with the outer surfaces of two or more of the electric wires and the inner surface of the tape member. [Effects of the Invention]

[0007] According to the present invention, a cable is realized in which the reduction in flexibility is suppressed even while including an intervening material. [Brief explanation of the drawing]

[0008] [Figure 1] This is a cross-section of the cable. [Figure 2] This is a schematic diagram of a harness using cables. [Figure 3] This is a schematic diagram of a vehicle equipped with a wiring harness. [Modes for carrying out the invention]

[0009] Hereinafter, an example of an embodiment of the present invention will be described in detail with reference to the drawings. In all drawings used to describe the embodiment, the same or substantially the same components and elements will be denoted by the same reference numerals. Furthermore, components and elements that have already been described will not be described again in principle.

[0010] (Cable overview) Figure 1 is a cross-sectional view of the cable 1 according to this embodiment. The cross-section of the cable 1 shown in Figure 1 is perpendicular to the longitudinal direction of the cable 1.

[0011] Cable 1 comprises a stranded wire bundle 2, a tape member 3, and a sheath 4. While the application of Cable 1 is not particularly limited, it is suitable for use as a cable in vehicle harnesses and robot arm harnesses. Harnesses using Cable 1 will be described in more detail later.

[0012] (Twisted wire assembly) The stranded wire assembly 2 is composed of multiple twisted wires and intervening materials. More specifically, the stranded wire assembly 2 is composed of two power supply wires 11 and 12, one signal wire 20, and two intervening materials 31 and 32.

[0013] The power wires 11 and 12, the signal wire 20, and the intervening elements 31 and 32 are all twisted together in the same direction. More specifically, the power wires 11 and 12, the signal wire 20, and the intervening elements 31 and 32 are twisted clockwise within the cross-section shown in Figure 1.

[0014] (power wire) In the following explanation, power supply wire 11 may be referred to as "power supply wire 11," and power supply wire 12 may be referred to as "power supply wire 12." Also, power supply wire 11 and power supply wire 12 may be collectively referred to as "power supply wire 10" or "power supply wire 10."

[0015] The power wire 10 is an insulated wire comprising a central conductor 13 and an insulator 14 covering the central conductor 13. The outer diameter of the power wire 10 can be changed as appropriate, but in this embodiment, the outer diameter of the power wire 10 is approximately 3 mm. In this embodiment, the power wire 11 and the power wire 12 are in contact.

[0016] The central conductor 13 is formed from a highly conductive wire such as copper. The insulator 14 is formed from an insulating resin. Furthermore, the central conductor 13 is a stranded wire formed by twisting together multiple wires. The insulator 14 is formed from, for example, cross-linked polyethylene (PE) or flame-retardant cross-linked polyethylene (PE).

[0017] (Signal wires) In the following description, the signal electric wire 20 may be referred to as "signal wire 20". The signal wire 20 is an insulated wire including a pair of core wires 21a, 21b and an internal sheath 22 covering the core wires 21a, 21b. Viewed differently, the signal wire 20 is a multi-core wire including a pair-twisted wire 21 formed by twisting a pair of core wires 21a, 21b together and an insulator covering the pair-twisted wire 21. Note that the pair of core wires 21a, 21b are twisted counterclockwise (left-handed) in the cross-section shown in FIG. 1. That is, the twisting direction of the pair-twisted wire 21 is opposite to the twisting direction of the twisted wire assembly 2.

[0018] The outer diameter of the signal wire 20 can be appropriately changed, but the outer diameter of the signal wire 20 in this embodiment is about 4.3 mm. That is, the outer diameter of the signal wire 20 is larger than the outer diameter of the power supply wire 10. In this embodiment, the signal wire 20 is in contact with the power supply wire 11 and the power supply wire 12.

[0019] The core wires 21a, 21b are insulated wires including a central conductor 24 and an insulator 25 covering the central conductor 24. Each central conductor 24 is a twisted wire formed by twisting a plurality of conducting wires together. Also, each insulator 25 is formed of, for example, cross-linked PE (polyethylene) or flame-retardant cross-linked PE (polyethylene).

[0020] The internal sheath 22 is formed of a soft resin excellent in flexibility and durability. The internal sheath 22 in this embodiment is formed of soft thermoplastic polyurethane.

[0021] Note that the cable 1 according to this embodiment does not include a shield conductor covering the power supply wire 10 or the signal wire 20. Viewed differently, no conductive member capable of shielding electromagnetic waves is interposed between the power supply wire 10 and the signal wire 20. This is a configuration according to the usage state of the cable 1 to be described later, and does not exclude a cable including a shield conductor covering the power supply wire 10 or the signal wire 20 from the technical scope of the present invention.

[0022] However, the cable 1 of this embodiment, in which the power lines 10 and signal lines 20 are not covered by a shielding conductor, is more flexible and bendable than the cables of other embodiments in which the power lines 10 and signal lines 20 are covered by a shielding conductor, and is also lighter and has lower manufacturing costs.

[0023] (intervention) In the following explanation, intervening elements 31 and 32 may be collectively referred to as “intervening element 30”. Intervening element 30 is positioned between adjacent power lines 10 and signal lines 20 in the circumferential direction. More specifically, intervening element 31 is positioned between power line 11 and signal line 20, and intervening element 32 is positioned between power line 12 and signal line 20.

[0024] Each interlayer 30 is composed of multiple strands 33 twisted together. In other words, the interlayer 30 is an assembly composed of multiple strands 33 twisted together. Each strand 33 constituting the interlayer 30 is made of an insulating resin. For example, the strands 33 are made of urethane, EPDM (ethylene propylene diene rubber), silicone rubber, PE (polyethylene), PET (polyethylene terephthalate), etc. Note that the strands 33 may also be composed of multiple thin strands twisted together.

[0025] The twisting direction of the multiple strands 33 constituting the intervening 30 is opposite to the twisting direction of the stranded wire assembly 2. As previously described, the stranded wire assembly 2 (power line 10, signal line 20, intervening 30) is twisted clockwise in the cross-section shown in Figure 1. In contrast, the multiple strands 33 constituting the intervening 30 are twisted counterclockwise in the cross-section shown in Figure 1.

[0026] The intervening 30, which is composed of multiple strands 33 twisted together, has higher flexibility than linear or rod-shaped intervening (solid intervening that is not composed of multiple strands). In other words, the cable 1 including the intervening 30 has a reduced reduction in cable flexibility due to the presence of the intervening compared to other cables including linear or rod-shaped intervening.

[0027] Furthermore, by setting the twisting direction of the individual wires 33 constituting the intervening 30 to be opposite to the twisting direction of the stranded wire assembly 2, the coiling and waviness of the cable 1 are reduced.

[0028] The intervening 30 is primarily positioned during the manufacturing of the cable 1 with the purpose of making the outer shape (cross-sectional shape) of the cable 1 (sheath 4) closer to a circular or nearly circular shape. More specifically, the intervening 30 is positioned during the process of forming the sheath 4 around the tape member 3 with the purpose of making the outer shape of the cable 1 (sheath 4) closer to a circular or nearly circular shape.

[0029] The intervening 30, positioned at the above location for the above purpose, is in contact with the outer surfaces of two or more electric wires and the inner surface of the tape member 3. More specifically, intervening 31 is in contact with the outer surface of the power wire 11 (outer surface 14a of the insulator 14), the outer surface of the signal wire 20 (outer surface 22a of the inner sheath 22), and the inner surface 3a of the tape member 3. Intervening 32 is in contact with the outer surface of the power wire 12 (outer surface 14a of the insulator 14), the outer surface of the signal wire 20 (outer surface 22a of the inner sheath 22), and the inner surface 3a of the tape member 3. From another perspective, intervening 30, which is an assembly of multiple strands 33, has an outer diameter that allows it to simultaneously contact the power wire 10, the signal wire 20, and the tape member 3.

[0030] (Tape material) The tape member 3 is spirally wrapped around the stranded wire assembly 2 to prevent the sheath 4 from getting between multiple electric wires (power wire 11, power wire 12, and signal wire 20). The tape member 3 is, for example, a strip of paper or nonwoven fabric. In this embodiment, the tape member 3 is in contact with power wire 11, power wire 12, and signal wire 20.

[0031] The winding direction of the tape member 3 is opposite to the twisting direction of the stranded wire assembly 2. By winding the tape member 3 in the opposite direction to the twisting direction of the stranded wire assembly 2, the coiling and waviness of the cable 1 are reduced.

[0032] (sheath) The sheath 4 is made of an insulating resin. The sheath 4 is provided around the tape member 3 so as to cover the tape member 3. The sheath 4 is made of a soft resin that has excellent flexibility and durability. In this embodiment, the sheath 4 is made of soft thermoplastic urethane.

[0033] (Harness) Figure 2 is a schematic diagram of a harness 40 using cable 1. The harness 40 comprises cable 1 and a connector attached to at least one end of cable 1. More specifically, the harness 40 comprises connector 41 attached to one end of cable 1 and connectors 42, 43 attached to the other end of cable 1.

[0034] The ends of the power line 10 and signal line 20 of cable 1 extend from both ends of the sheath 4, respectively. Alternatively, both ends of the sheath 4 are removed, exposing the ends of the power line 10 and signal line 20.

[0035] Furthermore, when both ends of the sheath 4 are removed, not only the ends of the power lines 10 and signal lines 20, but also the ends of the intervening 30 are exposed. The exposed portion of the intervening 30 can be cut off at any time. At this time, since the intervening 30 is an assembly made up of multiple strands 33 twisted together, the exposed portion can be easily and reliably cut off. In other words, the cable 1 of this embodiment has excellent workability for terminal processing.

[0036] In the following explanation, the ends of the power lines 10 and signal lines 20 located on the left side in Figure 2 may be referred to as the "left end," and the ends of the power lines 10 and signal lines 20 located on the right side in Figure 2 may be referred to as the "right end." However, this distinction is merely for the convenience of explanation.

[0037] Connector 41 is attached to the left end of the exposed power wire 10, and connector 42 is attached to the right end of the exposed power wire 10. Connector 43 is attached to the right end of the exposed signal wire 20.

[0038] A wheel speed sensor 44 is attached to the left end of the exposed signal wire 20. The wheel speed sensor 44 is a magnetic sensor that detects changes in the surrounding magnetic field and outputs a signal according to the detection result.

[0039] (Example of harness usage) Figure 3 is a schematic diagram of a vehicle 50 equipped with a harness 40. The vehicle 50 is equipped with an electric parking brake (EPB). More specifically, an electric motor 60 for the EPB is mounted on a wheel 51. In addition, an EPB control unit 61 is provided in an ECU (electronic control unit) 62 mounted on the vehicle body 52.

[0040] The electric motor 60 for the EPB drives a piston to which brake pads are attached. When the piston is driven in the first direction by the electric motor 60 for the EPB, the brake pads are pressed against the disc rotor, generating braking force. On the other hand, when the piston is driven in the second direction by the electric motor 60 for the EPB, the brake pads move away from the disc rotor, and the braking force is lost.

[0041] When predetermined conditions are met, the EPB control unit 61 supplies a drive current to the EPB electric motor 60 for a predetermined time (for example, 1 second) to move the piston in the first direction. For example, when the parking brake operating switch 70 is operated by the driver from the off state to the on state, the EPB control unit 61 supplies a drive current to the EPB electric motor 60 for a predetermined time to move the piston in the first direction.

[0042] Furthermore, when predetermined conditions are met, the EPB control unit 61 supplies drive current to the EPB electric motor 60 and moves the piston in the second direction. For example, when the driver operates the parking brake actuation switch 70 from the ON state to the OFF state, or when the accelerator pedal is pressed, the EPB control unit 61 supplies drive current to the EPB electric motor 60 and moves the piston in the second direction.

[0043] In other words, the electric parking brake installed in the vehicle 50 remains activated after the parking brake activation switch 70 is turned ON, until the parking brake activation switch 70 is turned OFF or the accelerator pedal is pressed.

[0044] Vehicle 50 is equipped with an anti-lock braking system (ABS) in addition to an electric parking brake. More specifically, an ABS sensor 44 is located near the wheels 51. Furthermore, an ABS control unit 63 is provided in the ECU (electronic control unit) 62 mounted on the vehicle body 52.

[0045] The ABS control unit 63 controls the braking system based on the output of the ABS sensor 44. For example, the ABS control unit 63 intermittently activates the braking system based on the output of the ABS sensor 44 to prevent wheel lock-up.

[0046] The harness 40 electrically connects the ECU 62 and the electric motor 60 for the EPB. More specifically, a connector 41 (Figure 2) on the harness 40 is connected to a connector on the electric motor 60 for the EPB. Also, a connector 42 (Figure 2) on the harness 40 is connected to a connector on the junction box 64. When connector 42 is connected to the connector on the junction box 64, the power lines 10 of the harness 40 are electrically connected to the group of wires inside the junction box 64. As a result, the ECU 62 and the electric motor 60 for the EPB are electrically connected, and drive current is supplied to the electric motor 60 for the EPB based on the control of the EPB control unit 61.

[0047] The harness 40 electrically connects the ECU 62 and the ABS sensor 44. More specifically, the wheel speed sensor 44 (Figure 2) on the harness 40 is positioned near the wheel 51 as an ABS sensor. Also, the connector 43 (Figure 2) on the harness 40 is connected to a connector on the relay box 64. When the connector 43 is connected to the connector on the relay box 64, the signal line 20 of the harness 40 is electrically connected to the group of wires inside the relay box 64. As a result, the ECU 62 and the ABS sensor 44 are electrically connected, and the braking system is controlled based on the output of the ABS sensor 44.

[0048] In other words, the power lines 10 provided by the harness 40 form a power supply path for supplying drive current to the electric motor 60 for the EPB. In addition, the signal lines 20 provided by the harness 40 form a signal transmission path for transmitting signals output from the ABS sensor 44 to the ECU 62 (ABS control unit 63).

[0049] As previously stated, the cable 1 used in harness 40 does not have a shielded conductor. More specifically, there is no conductive material capable of shielding electromagnetic waves between the power line 10 and the signal line 20 of cable 1.

[0050] Therefore, if current flows through the power line 10, the electromagnetic waves generated by this current may electrically affect the signals transmitted through the signal line 20. However, the electric parking brake installed in the vehicle 50 operates mainly when the vehicle 50 is stopped. In other words, the drive current supplied to the electric motor 60 for the EPB via the power line 10 is mainly when the vehicle 50 is stopped.

[0051] On the other hand, the ABS system installed in vehicle 50 operates while vehicle 50 is in motion. In other words, the ABS system does not operate when vehicle 50 is stopped. Another way of looking at it is that when the vehicle is stopped (vehicle speed is zero), no signal is output from the ABS sensor 44, and no signal is transmitted via the signal line 20. At the very least, even if the signal transmitted via the signal line 20 is affected in some way, that effect can be ignored.

[0052] Therefore, in this embodiment, the shield conductor is omitted in order to prioritize the flexibility and bendability of the cable 1 and harness 40.

[0053] For convenience, only one wheel 51 is shown in Figure 3, but the vehicle 50 has four wheels, including the wheel 51 shown in the figure. The electric motor 60 for the EPB and the ABS sensor 44 may be provided on all four wheels, or only on the front wheels or only on the rear wheels.

[0054] The present invention is not limited to the embodiments described above, and various modifications are possible without departing from its spirit. For example, the internal sheath 22 shown in Figure 1 can be omitted. In this case, the outer circumferential surface of the insulator 25 of the core wires 21a and 21b corresponds to the outer circumferential surface of the signal wire 20 in contact with the intervening 30.

[0055] The power line 10 of the harness 40 (cable 1) can also be used to supply drive current to the electric motor of the electromechanical brake (EMB). In this case, since current flows through the power line 10 even while the vehicle is running, it is preferable to provide a shielded conductor on at least one of the power line 10 and the signal line 20.

[0056] The wheel speed sensor 44 in the harness 40 can be replaced with other sensors. For example, the wheel speed sensor 44 can be replaced with a temperature sensor or an air pressure sensor.

[0057] The signal line 20 of harness 40 (cable 1) can also be used to transmit signals for controlling the vibration damping device installed in the vehicle, or signals for controlling the EMB (Electromagnetic Mixer). [Explanation of symbols]

[0058] 1…Cable, 2…Stranded wire assembly, 3…Tape material, 3a…Inner surface, 4…Sheath, 10,11,12…Power wire (power line), 13…Center conductor, 14…Insulator, 14a…Outer surface, 20…Signal wire (signal line), 21…Paired strand, 21a,21b…Core wire, 22…Internal sheath, 22a…Outer surface, 24…Center conductor, 25…Insulator, 30,31,32…Interlayer, 33…Strand wire, 40…Harness, 41,42,43…Connector, 44…Wheel speed sensor (ABS sensor), 50…Vehicle, 51…Wheel, 52…Vehicle body, 60…Electric motor for EPB, 61…EPB control unit, 62…ECU (Electronic Control Unit), 63…ABS control unit, 64…Relay box, 70…Parking brake actuation switch

Claims

1. A stranded wire assembly in which multiple electric wires and multiple intervening materials are twisted together, A tape member wrapped around the aforementioned stranded wire assembly, The tape member comprises a sheath that covers the periphery of the tape member, Each of the aforementioned intervenes is composed of multiple strands twisted together and is in contact with the outer surface of two or more of the aforementioned electric wires and the inner surface of the tape member. Each of the aforementioned wires constituting the intervening is formed of an insulating resin. A cable in which the twisting direction of the plurality of strands constituting the intervening is opposite to the twisting direction of the stranded wire assembly.

2. A stranded wire assembly in which multiple electric wires and multiple intervening materials are twisted together, A tape member wrapped around the aforementioned stranded wire assembly, The tape member comprises a sheath that covers the periphery of the tape member, Each of the aforementioned intervenes is composed of multiple strands twisted together and is in contact with the outer surface of two or more of the aforementioned electric wires and the inner surface of the tape member. A cable in which the twisting direction of the plurality of strands constituting the intervening is opposite to the twisting direction of the stranded wire assembly.

3. The cable according to claim 1 or 2, wherein the winding direction of the tape member is opposite to the twisting direction of the stranded wire assembly.

4. The cable according to claim 1 or 2, A harness comprising a connector attached to at least one end of the aforementioned cable.

5. The cable according to claim 3, A harness comprising a connector attached to at least one end of the aforementioned cable.

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