JP2023082180A5 - Electric wire, electric wire inspection system and electric wire inspection method - Google Patents

Claims (13)

A core wire having a conductor and an insulating coating covering the outer periphery of the conductor and exposed on the surface;
and a laminated tape arranged on the outer periphery of the core wire,
The laminated tape has a base material configured as a tape-shaped insulator or semiconductor, and conductive coating layers respectively formed on both sides of the base material,
The electric wire, wherein the outer periphery of the laminated tape is not covered with another member, or is covered with a layer composed of an organic polymer, and is exposed on the outer surface of the electric wire as a whole. The core wire is in a state of a wire harness in which a plurality of core wires are bundled,
The electric wire according to claim 1, wherein the laminated tape is spirally wound around the outer periphery of the wire harness as a whole. The electric wire according to claim 1 or 2, wherein portions in which the base material is exposed without being formed with the coating layer are provided at both ends in the width direction of the laminated tape. The electric wire according to any one of claims 1 to 3, wherein the base material has electrical properties that change depending on the external environment. The electric wire according to any one of claims 1 to 4, which has a branch part in the middle. A wire inspection system for inspecting a damaged state of the wire according to any one of claims 1 to 5,
An electric signal containing an AC component is input as a test signal to the two coating layers constituting the laminated tape of the electric wire, and the characteristic impedance between the two coating layers is obtained as a response signal. Electric wire inspection,
The wire inspection system includes:
a storage unit that stores, at a first point in time, the response signal obtained by the wire inspection for each wire group including the plurality of wires;
an inspection unit that performs the wire inspection on a target wire selected from the wire group at a second time after the first time;
For the target wire, the response signal at the first point in time is called from the storage unit, compared with the response signal acquired by the inspection unit at the second point in time, and the two response signals are and an analysis unit that determines that damage exists in the target electric wire when a difference exists. 7. The wire inspection system according to claim 6, wherein said storage unit is provided at a location remote from said inspection unit and said analysis unit. The analysis unit obtains a difference between the response signal at the first time point and the response signal at the second time point, and determines whether there is a difference between the two response signals based on the difference. 8. The wire inspection system according to claim 6 or 7, which determines In the wire inspection, as the response signal, the characteristic impedance between the two coating layers is measured by a time domain reflection method or a frequency domain reflection method,
The analysis unit detects a region in which a difference occurs in the response signal between the response signal at the first time point and the response signal at the second time point along the axial direction of the electric wire. The electric wire inspection system according to any one of claims 6 to 8, which determines that damage occurs at that position. The test signal is obtained by superimposing components over a continuous frequency range with independent intensity for each frequency, and in the frequency range, some frequency components are missing or compared with surrounding frequencies. contains excluded frequencies with discontinuously decreasing intensity,
10. The wire inspection system according to claim 9, wherein in the wire inspection, as the response signal, the characteristic impedance between the two coating layers is measured by a time domain reflection method. 11. The wire inspection system according to claim 10, wherein in the inspection signal, the excluded frequencies include frequencies of electromagnetic waves originating from sources external to the target wire and propagating around the target wire. The electric wire inspection system according to any one of claims 6 to 11, wherein the electric wire group includes a plurality of electric wires of the same type. Using the wire inspection system according to any one of claims 6 to 12,
an initial data acquisition step of performing the wire inspection on the wires constituting the wire group at the first time point and acquiring the response signal;
a data storage step of storing the response signal acquired in the initial data acquisition step in the storage unit for each individual wire;
a measurement step of performing the wire inspection on the target wire by the inspection unit at the second time point;
The analysis unit retrieves the response signal acquired at the first time point from the storage unit for the target wire, compares it with the response signal acquired in the measurement step at the second time point, and and an analysis step of determining that the target wire is damaged when there is a difference between the two response signals.