JPH11326223A - Fume-testing device and method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a fume-testing device for obtaining a reliable test result. SOLUTION: An electric wire W is supported while it is extended in a horizontal direction in an airtight testing bath 2. While a specific overcurrent is allowed to flow to the electric wire W, laser beams L are applied in the longitudinal direction of the electric wire W at the upper position of the electric wire W, and the scattered light of the laser beams L is monitored by a photosensor 22 such as a photomultiplier. When smoke is generated from an inspection target part A of a middle part in the longitudinal direction of the electric wire W, the laser beams L are scattered due to the smoke and are detected by the photosensor 22, and the generation of the smoke is detected. A cylindrical screening member 20 for covering a path part that is a path part where the laser beams L are applied excluding the corresponding path part with the inspection target A is provided, thus preventing the scattered light from the laser beams L from occurring due to smoke being generated from a part other than the inspection target part A of the electric wire W.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a smoke test apparatus and a smoke test method for detecting the smoke of an electric wire due to an overcurrent and measuring the start time of the smoke to inspect the characteristics of the electric wire.

[0002]

2. Description of the Related Art Conventionally, as one of the test methods for examining the limit to overcurrent of a covered electric wire such as an electric wire for an automobile, an overcurrent is applied to the electric wire so that a covering layer portion is generated by heat generation of a conductor from the start of energization. There is known a method of measuring the time until smoke is generated and using the measured time as a standard for evaluating the electric wire.

[0003] As this kind of technology, for example, Japanese Patent Laid-Open No.
There is a smoke test apparatus disclosed in 186277 and JP-A-9-178550.

In these smoke test apparatuses, as shown in FIG. 6, an electric wire W is supported in a state of being stretched horizontally in an airtight test tank 200, and a constant overcurrent is caused to flow through the electric wire W. I have. In addition, a laser light source 202 provided on one side of the test tank 200 irradiates a laser beam L in parallel to the direction in which the electric wires W are provided, and a light from a photomultiplier tube or the like provided on the inner back side of the test tank 200. The scattered light of the laser light L is monitored by the sensor 206.

[0005] When smoke S is generated from the electric wire W due to the overcurrent, the smoke S scatters the laser beam L, and the scattered light is detected by the optical sensor 206, thereby detecting the generation of the smoke S. It is supposed to be.

Further, the test tank 200 is provided with an exhaust fan (not shown) and an inlet for absorbing outside air. After the test, the exhaust fan is operated to activate the inside of the test tank.
The configuration is such that the air inside 00 is discharged and fresh air is introduced into the test tank 200 through the introduction port. The inlet is provided with a lid that can be opened and closed, and the lid is closed during the smoke test.

[0007]

However, with the above-described apparatus, reliable test results cannot be obtained for various reasons as described below.

First, gripping terminals for passing an overcurrent are attached to both ends of the electric wire W, and heat is exchanged between the gripping terminal and the electric wire. The temperature corresponding to the heat generated by the electric wire W is in the middle portion in the longitudinal direction of the electric wire W. Therefore, when it is desired to detect an accurate time until smoke is generated on the electric wire W due to the overcurrent, it is necessary to detect only the smoke S generated at the longitudinal middle portion of the electric wire W. However, in the above-mentioned smoke test apparatus, the laser beam L extends over the entire length of the electric wire W in the test tank 200 in the longitudinal direction.
Therefore, the laser light L is scattered by the smoke S generated outside the middle part in the longitudinal direction of the electric wire W, and the scattered light is detected by the optical sensor 206.
This is because it is not possible to accurately detect the time until the start of smoking due to the overcurrent.

Second, as described above, in order to detect an accurate time until the start of smoking due to an overcurrent, the scattered light of the laser light L due to the smoke S generated at the longitudinal middle portion of the electric wire W is detected. Although it is necessary, the laser light L is attenuated by the smoke S generated at a portion other than the middle portion of the electric wire W before the laser light L reaches the middle portion in the longitudinal direction of the electric wire W, and the important electric wire W The scattered light of the laser beam L due to the smoke S generated in the intermediate portion is not sufficiently obtained, and a difference occurs between the time when the smoke S is generated in the intermediate portion and the detection time of the scattered light due to the smoke S. The reason is that.

Third, even if the smoke S is generated from the middle portion in the longitudinal direction of the same electric wire W, the place where the smoke S is generated from the electric wire W differs depending on the magnitude of the overcurrent flowing through the electric wire W. It is due to. That is, when the overcurrent is relatively small, the ambient temperature around the electric wire W is sufficiently high before the smoke S is generated, so that the position where the smoke particles cool down and the laser light L is scattered. Is a position considerably away from the electric wire W upward. On the other hand, when the overcurrent is large, smoke is generated from the electric wire W before the surrounding atmosphere of the electric wire W is warmed up. Will be scattered. Accordingly, when only one laser beam L is irradiated in parallel with the longitudinal direction of the electric wire W as in the smoke test apparatus shown in FIG. Can not be done.

The present invention has been made in order to solve the above-described problems, and has as its object to provide a smoke test apparatus and a smoke test method capable of obtaining a reliable test result.

[0012]

According to a first aspect of the present invention, there is provided a smoke test apparatus for accommodating an electric wire in which a portion to be inspected for a smoke test is set at an intermediate portion in a longitudinal direction. Airtight test tank, a pair of holding means for flowing a predetermined current through the wire while supporting the wire in a state stretched in a horizontal direction at a predetermined position in the test tank, A laser light source for irradiating a laser beam parallel to a longitudinal direction of the electric wire at an upper position, and a position capable of detecting the scattered light of the laser light scattered by smoke generated from an inspection target portion by energizing the electric wire; A light detection means for detecting the generation of smoke from the inspection target by detecting the scattered light thereof, and a corresponding path between the laser light irradiation path and the inspection target part of the electric wire. Department And a tubular shield member that covers at least between the laser light source and the corresponding path portion of the path portion except.

It is more preferable that the cylindrical shielding member covers the entire path portion of the laser beam irradiation path except for the path portion corresponding to the inspection target portion of the electric wire.

Further, as in claim 3, air introducing means for passing air outside the test tank through the cylindrical shielding member to introduce the air into the test tank, and a peripheral wall portion of the test tank. An air exhaust means provided to exhaust the air in the test vessel may be provided.

According to a fourth aspect of the present invention, there is provided a smoke test method according to the first aspect, wherein an electric wire in which an inspection target portion of the smoke test is set at a middle portion in the longitudinal direction is stretched horizontally at a predetermined position in an airtight test tank. Supporting, flowing a predetermined current through the electric wire, and cylindrical shielding at least between the laser light source and the corresponding path portion in a path portion of the irradiation path excluding the corresponding path portion with the inspection target portion. In the state covered with the member, a step of irradiating a laser beam parallel to the longitudinal direction of the electric wire, and applying a predetermined current to the electric wire and irradiating the laser beam parallel to the longitudinal direction of the electric wire, from the electric wire Detecting smoke generation by detecting scattered light of the laser light scattered by the generated smoke.

According to a fifth aspect of the present invention, the laser beam is covered by the cylindrical shielding member so as to cover the entire laser beam irradiation path except the path corresponding to the inspection target portion of the electric wire. Light may be applied.

Further, after the step of detecting smoke, the air outside the test tank is introduced into the test tank through the cylindrical shielding member, and the inside of the test tank is detected. The method may include a step of performing ventilation by exhausting air.

Further, in the smoke test apparatus according to the present invention, an airtight test tank for accommodating an electric wire in which an inspection target part of the smoke test is set at an intermediate portion in a longitudinal direction, and a predetermined position in the test tank. A pair of holding means for allowing a predetermined current to flow through the wire, and a pair of holding means for allowing a predetermined current to flow through the wire, and A plurality of laser light sources provided at intervals, each for irradiating a laser beam parallel to the longitudinal direction of the electric wire, and the respective laser lights scattered by smoke generated from the inspection target portion by energizing the electric wire And a light detecting means for detecting the scattered light and detecting smoke generated from the inspection target portion by detecting the scattered light.

According to another aspect of the present invention, a plurality of cylindrical shielding members respectively covering the laser light irradiation paths of the respective laser light sources and excluding the path portions corresponding to the inspection target portion of the electric wire. May be provided.

According to a ninth aspect of the present invention, there is provided a smoke test method according to the first aspect, wherein an electric wire having an inspection target portion set in a middle portion in a longitudinal direction is horizontally stretched to a predetermined position in an airtight test tank. A step of supporting, a step of flowing a predetermined current through the electric wire, and a plurality of laser light sources provided at predetermined intervals along the up-down direction at positions above one end of the arrangement position of the electric wire, each of which is above the electric wire. Irradiating a plurality of laser beams parallel to a longitudinal direction of the electric wire at a position, and applying a predetermined current to the electric wire and irradiating the laser light parallel to the longitudinal direction of the electric wire, thereby forming smoke generated from the electric wire. Detecting smoke by detecting the scattered light of each of the laser lights scattered by the laser light.

Further, in the smoke test apparatus according to the present invention, an airtight test tank for accommodating an electric wire in which an inspection target part of the smoke test is set at an intermediate portion in the longitudinal direction, and a predetermined position in the test tank. A pair of holding means for supporting the electric wire in a state where the electric wire is stretched in the horizontal direction, and for flowing a predetermined current through the electric wire, and a predetermined interval along the vertical direction at a position above the arrangement position of the electric wire. A plurality of laser light sources for irradiating a laser beam parallel to the horizontal direction orthogonal to the longitudinal direction of the electric wire, and are scattered by smoke generated from the inspection target portion by energizing the electric wire. A light detection unit provided at a position where the scattered light of each of the laser lights can be detected, and detecting the scattered light to detect smoke generated from the inspection target portion.

The laser light sources may be arranged in a matrix at a position above the position where the electric wires are provided, and the laser light emitted from the laser light sources may be applied to the electric wires. You may make it pass above the electric wire in several positions along a longitudinal direction.

[0023] Further, the smoke test method according to claim 12 is characterized in that:
A step of supporting an electric wire in which the inspection target part of the smoke test is set in the middle part in the longitudinal direction in a state where the electric wire is horizontally stretched at a predetermined position in the airtight test tank, and a step of flowing a predetermined current through the electric wire; Irradiating a laser beam parallel to a horizontal direction orthogonal to a longitudinal direction of the electric wire by a plurality of laser light sources provided at predetermined intervals along a vertical direction at a position above the arrangement position of the electric wire. And detecting a scattered light of any one of the laser lights scattered by smoke generated from the electric wire while applying a predetermined current to the electric wire and irradiating the laser light parallel to the longitudinal direction of the electric wire. And detecting a fuming.

According to a thirteenth aspect of the present invention, a plurality of laser light sources are arranged in a matrix at a position above the arrangement position of the electric wires, and the laser light sources are arranged along the longitudinal direction of the electric wires from these laser light sources. A plurality of positions may be irradiated with a laser beam passing above the electric wire.

Further, a smoke test apparatus according to claim 14 is
An airtight test tank for accommodating the electric wire in which the inspection target part of the smoke test is set in the middle part in the longitudinal direction, and while supporting the electric wire at a predetermined position in the test tank in a state where the electric wire is stretched horizontally. Holding means for causing a predetermined current to flow through the wire, and irradiating visible light from one side of the arrangement position of the wire toward an upper position of the inspection target portion to conduct the inspection by energizing the wire. A visible light source for illuminating smoke generated from the target unit, an imaging unit for imaging an image near the inspection target unit including the visible light irradiation region from the same direction as the visible light irradiation direction, and the imaging unit Based on the image obtained by the means, the area of the illuminated portion of the smoke contained in the image in the predetermined inspection target area set to include only the position above the inspection target part of the electric wire in the image is a predetermined area. Value exceeded And a smoke generation detection means for detecting detects and smoke.

Further, according to the smoke test method of the present invention, the electric wire having the inspection target portion set in the middle portion in the longitudinal direction is stretched horizontally at a predetermined position in an airtight test tank. The step of supporting, the step of flowing a predetermined current through the electric wire, and irradiating visible light from one side of the arrangement position of the electric wire toward an upper position of the inspection target portion to energize the electric wire, Illuminating the smoke generated from the inspection target portion, and capturing an image of the vicinity of the inspection target portion including the visible light irradiation region from the same direction as the visible light irradiation direction, and applying a predetermined current to the electric wire. While taking an image of the vicinity of the inspection object by irradiating visible light to the position above the inspection object part while flowing, based on the image obtained by the imaging means, based on the image obtained by the imaging means, Including only Area of light out portions of a predetermined smoke contained in the inspection target region in an image and a step of detecting smoke by detecting that exceeds a predetermined value set in.

[0027]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a smoke test apparatus according to a first embodiment of the present invention will be described with reference to FIG.

In this smoke test apparatus, when a certain overcurrent is applied to the electric wire W having the coating layer formed around the conductor, the time from the start of energization until the generation of smoke from the coating layer (smoke time).
Is used to inspect the characteristics of the electric wire W. A pair of holding means 10 is provided on both sides 2a of the airtight test tank 2 and the test tank 2
A laser light source 15 is provided on one side surface 2a.

Insertion holes 3 through which the electric wires W are inserted are formed on both side surfaces 2a of the test tank 2, and both ends of the electric wires W are drawn out of the insertion holes 3 to the outside. The electric wire W is configured to be accommodated in the test tank 2.

Further, holding means 10 for holding the ends of the electric wires W are provided on both sides 2a of the test tank 2 on the outer side of the insertion holes 3 respectively. Each holding means 10 holds the end of the electric wire W drawn out from the insertion hole 3 and supports it in a state of being pulled outward. Thereby, the electric wire W is supported in the test tank 2 while being stretched in the left and right horizontal directions.

Further, each holding means 10 has a function as an electrode for flowing a constant overcurrent through the conductor of the electric wire W. That is, the covering layer at both ends of the electric wire W is peeled in advance to expose the conductive wire therefrom, and the exposed portion is gripped by each holding means 10 as described above, so that the conductive wire of the electric wire W is fixed to the conductive wire. It is configured to allow an overcurrent to flow.

The test tank 2 is provided with a heater (not shown), so that the temperature inside the test tank 2 can be adjusted to a constant temperature within a range from normal temperature to 120 ° C.

By the way, in the present smoke test apparatus in which the electric wire W is supported as described above, the middle part in the longitudinal direction of the electric wire W in the test tank 2, more precisely, the central part between the holding parts by the two holding means 10. Is set in the inspection target part A. In this way, the reason for setting the middle portion in the longitudinal direction of the electric wire W as the inspection target portion A is that heat is exchanged between the both ends of the electric wire W with the holding means 10 that grips the electric wire W, That is, in order to eliminate these external factors and to test the generation time of the smoke caused only by the heat generated by the overcurrent flowing through the conductor of the electric wire W, it is necessary to determine the time at which the smoke is generated at the longitudinal middle portion of the electric wire W. Is preferably tested.

The laser light source 15 is provided on one side 2 of the test tank 2.
It is provided above the holding means 10 on the a side. In the laser light source 15, the laser light L (indicated by a dashed line in FIG. 1) emitted from the laser light source 15 is located above the position where the electric wire W is provided,
In addition, the electric wire W is attached in such a manner that light is emitted from one side toward the other side in parallel with the longitudinal direction of the electric wire W.

A cylindrical shielding member 20 is provided inside the test tank 2 along the irradiation path of the laser beam L.
This cylindrical shielding member 20 is provided with a central portion of the irradiation path of the laser light L in the test tank 2, that is, a part of the irradiation path of the laser light L corresponding to the inspection target portion A of the electric wire W. It is configured so as to cover the path portions on both end sides that have been removed.

For example, when the width of the test tank 2 is about 1 m, it is preferable to leave the center of the test tank 2 at about 30 cm.

Further, an optical sensor 22 such as a photomultiplier tube is provided on the inner side of the test tank 2. This optical sensor 2
2 is connected to a detection unit not shown, and as described later, when a laser beam L is scattered by smoke generated from the inspection target portion A of the electric wire W by flowing a constant overcurrent,
The scattered light is detected by the optical sensor 22 and a detection signal is output to the detection unit. The detection unit detects the generation of scattered light, that is, the generation of smoke.

An air introduction pipe 2 communicating with the inside of the cylindrical shielding member 20 is provided at the base end of the cylindrical shielding member 20.
4, the air introduction pipes 24 are drawn out of the test vessel 2 and the other end is connected to a compressed air supply device or the like (not shown), thereby constituting an air introduction means.

Further, an exhaust fan 26 is provided at the center of the upper part of the test tank 2.

When the test by the smoke test apparatus is completed, the test tank 2 is supplied from the compressed air supply device or the like.
Outside air through the air introducing pipe 24 to the cylindrical shielding member 2
In addition, by introducing the air into the test chamber 2 and operating the exhaust fan 26 to exhaust the air in the test chamber 2 to the outside, it is possible to ventilate the air in the test chamber 2 to fresh air without smoke. Is configured.

Next, a method of performing a smoke test using the smoke test apparatus will be described.

First, the electric wires W, whose covering layers at both ends are previously peeled off to expose the conductive wires, are inserted into the insertion holes 3 on both side surfaces 2a of the test tank 2, and are drawn out from the insertion holes 3 to the outside. The held end of the electric wire W is gripped by the holding means 10 and accommodated in the test tank 2 in a state where the electric wire W is stretched horizontally.

Next, the laser light L is irradiated from the laser light source 15 while a constant overcurrent is applied to the conductor of the electric wire W by the holding means 10, and the scattered light of the laser light L is monitored by the optical sensor 22.

When heat is generated due to the overcurrent, smoke is generated from the coating layer of the inspection target portion A at the middle portion in the longitudinal direction of the electric wire W, and the smoke rises to the irradiation path of the laser beam L. Does not have the cylindrical shielding member 20, the laser light L is scattered by the smoke. As a result, the scattered light is detected by the optical sensor 22 and a detection signal is given to the detection unit. In this manner, smoke is detected from the inspection target portion A, and the smoke emission time is obtained.

On the other hand, smoke generated from portions other than the inspection target portion A of the electric wire W is blocked by the cylindrical shielding member 20 and rises avoiding the irradiation path of the laser beam L, and scattered light by the smoke is generated. Is not detected by the optical sensor 22.

After the smoke is thus generated, the inside of the test tank 2 is ventilated when the next smoke test is performed by changing the magnitude of the overcurrent or the type of the electric wire.

This ventilation is performed by introducing air outside the test tank 2 from the compressed air supply device or the like into the cylindrical shielding member 20 through the air introducing pipe 24, while exhausting air from the exhaust fan 26 of the test tank 2.
Is operated to exhaust the air in the test tank 2 to the outside, thereby ventilating the air in the test tank 2 to fresh air without smoke.

According to the smoke test apparatus configured as described above, the cylindrical shielding member 20 is provided to cover the path of the irradiation path of the laser beam L except the path corresponding to the inspection target portion A of the electric wire W. Therefore, there is no possibility that smoke generated from a portion other than the inspection target portion A of the electric wire W enters the irradiation path of the laser light L and causes the laser light L to be scattered. Therefore, only the scattered light of the laser light L due to the smoke generated in the inspection target portion A can be detected by the optical sensor 22. In this way, a smoke test due to an overcurrent of the electric wire W can be performed while eliminating external factors such as contact between the electric wire W and the holding means 10 as much as possible, and a reliable test result can be obtained.

Further, smoke generated from a portion other than the inspection target portion A of the electric wire rises through the outer periphery of the cylindrical shielding member 20, so that the laser beam L passing through the inside of the cylindrical shielding member 20.
Is not attenuated by the smoke,
From the inspection target part A
Smoke generated in the test produces sufficient scattered light, and there is no difference between the time when the smoke is actually generated and the time when the scattered light is detected by the smoke. The result can be obtained. In order to obtain this effect, it is not necessary to cover the entire path portion of the irradiation path of the laser beam L except for the corresponding path portion with the inspection target portion A of the electric wire W. Of these, at least the portion between the laser light source 15 and the corresponding path portion may be covered by the cylindrical shielding member 20.

Further, after the end of the smoke test, before ventilating the test tank 2 before performing the next test, the test tank 2 must be ventilated.
Is introduced into the test tank 2 through the cylindrical shielding member 20, and the air in the test tank 2 is discharged to the outside by an exhaust fan 26 provided at the center of the upper surface of the test tank 2. Therefore, even if the cylindrical shielding member 20
Even if smoke enters the inside, the smoke that has entered the cylindrical shielding member 20 due to the air ventilation is discharged to the outside. Thereby, even if this smoke test is repeatedly performed continuously, the smoke remaining in the previous test does not adversely affect the next test, and a highly accurate test can be performed repeatedly and continuously.

Next, a smoke test apparatus according to a second embodiment of the present invention will be described with reference to FIG.

The smoke test apparatus is similar to the smoke test apparatus of the first embodiment, when a certain overcurrent is applied to an electric wire W having a coating layer formed around a conductor, the coating layer is formed. By measuring the time it takes for smoke to form from
A pair of holding means 60 are provided on both sides 52 a of the airtight test tank 52 for inspecting the characteristics of the electric wire W. These test tank 52 and holding means 60 are
The electric wire W is supported by the same configuration as the test tank 2 and the holding means 10 of the first embodiment, and the description is omitted here.

Further, for the same reason as in the first embodiment, the inspection target portion A is set at the middle portion in the longitudinal direction of the electric wire W.

In this smoke test apparatus, three laser light sources 65 are connected to the holding means 60 on one side surface 52 a of the test tank 52.
At a predetermined interval in the vertical direction. These laser light sources 65 are arranged such that laser beams L (indicated by dashed lines in FIG. 2) emitted from the laser light sources 65 are located above the position where the electric wire W is provided, and are arranged in three rows in parallel with the longitudinal direction of the electric wire W. It is mounted so that it is irradiated with.

An optical sensor 72 having the same configuration as the optical sensor 22 of the first embodiment is provided on the inner side of the test tank 52.

Hereinafter, a smoke test method using the smoke test apparatus will be described.

First, as in the case of the first embodiment,
The electric wire W is accommodated in the test tank 52 in a state of being stretched horizontally.

Next, the laser light L is emitted from each laser light source 65 while a constant overcurrent is applied to the conductor of the electric wire W by the holding means 60, and the scattered light of the laser light L is monitored by the optical sensor 72.

When heat is generated by the overcurrent, smoke is generated from the coating layer of the inspection target portion A at, for example, the middle portion in the longitudinal direction of the electric wire W, and the laser beam L having an optical path corresponding to the place where the smoke is generated is generated. The light is scattered by the smoke, and the scattered light is detected by the optical sensor 722 to detect smoke.

At this time, the location where smoke causing scattering of the laser light L is generated depends on the magnitude of the overcurrent flowing through the electric wire W.
Although it is located far away from the current W or just above the electric wire W, a plurality of laser beams L are irradiated above the electric wire W in parallel at different heights. Any one of the laser beams L is scattered by the smoke, and the smoke is accurately detected.

According to the smoke test apparatus configured as described above, a plurality of laser light sources 65 are provided on one side of the arrangement position of the electric wires W at predetermined intervals along the vertical direction. The laser beam L parallel to each other is irradiated in a plurality of rows along the direction from one side to the other side while changing the height in the vertical direction. Even if the place where smoke causing the scattering of the light L is generated fluctuates in the vertical direction, any of the laser lights L
Are scattered by the smoke, which can be detected by the optical sensor 72. Therefore, even if various smoke tests are performed in which the magnitude of the overcurrent flowing through the electric wire W is different, a reliable test result can be obtained.

The path portion of the irradiation path of each laser beam L excluding the path portion corresponding to the inspection target part A of the electric wire W is
By covering with a cylindrical shielding member having the same configuration as the cylindrical shielding member 20 of the first embodiment, a more reliable test result can be obtained for the same reason as described in the first embodiment. Becomes At this time, the laser light source 6
Even when only the portion corresponding to the corresponding path portion between the inspection target portion 5 and the inspection target portion A is covered with the cylindrical shielding member, as described in the first embodiment, the laser light L is emitted from portions other than the inspection target portion A. A reliable test result can be obtained in that the smoke generated from the inspection target portion A reaches the smoke generated without being attenuated by the generated smoke.

When the cylindrical shielding member is provided in this manner, similarly to the case of the first embodiment, the air introducing tube 24 is connected to the base end of the cylindrical shielding member, and the air introducing tube is provided. Is drawn out of the test tank 2 and connected to a compressed air supply device or the like to form air introduction means.
If an exhaust fan is provided in the upper part of the air vent, even if smoke enters the cylindrical shielding member during the smoke test, the air ventilation may be performed for the same reason as in the first embodiment. Accordingly, the smoke that has entered the cylindrical shielding member is discharged to the outside. Thereby, even if this smoke test is repeatedly performed continuously, the smoke remaining in the previous test does not adversely affect the next test, and a highly accurate test can be performed repeatedly and continuously.

Next, a smoke test apparatus according to a third embodiment of the present invention will be described.

The smoke test apparatus is similar to the smoke test apparatus of the first embodiment, when a certain overcurrent is applied to an electric wire W having a coating layer formed around a conductive wire, the coating layer is formed. By measuring the time it takes for smoke to form from
This is for inspecting the characteristics of the electric wire W, and a pair of holding means 11 is provided on both side surfaces 102 a of the airtight test tank 102.
0 is provided. The test tank 102 and the holding means 110 support the electric wire W with the same configuration as the test tank 2 and the holding means 10 of the first embodiment, and the description thereof is omitted here.

For the same reason as in the first embodiment, the inspection target portion A is set at the middle portion in the longitudinal direction of the electric wire W.

In this smoke test apparatus, three rows × the side of the arrangement position of the electric wire W, that is, the back surface 102c side of the test tank 102
A total of nine laser light sources 115 in three rows are provided. The laser light sources 115 are arranged in a matrix at predetermined positions along the vertical direction and the longitudinal direction of the wires W at a position higher than the position where the wires W are provided. Then, each laser light source 11
When laser light L (indicated by a dashed line in FIG. 3) is emitted from 5, the laser light L moves the position above the inspection target portion A of the electric wire W along a direction orthogonal to the longitudinal direction of the electric wire W. The test tank 102 is configured to be irradiated from the back side to the front side in parallel with each other.

The upper surface 102b inside the test tank 102
The optical sensor 12 having the same configuration as the optical sensor 22 of the first embodiment is located on the side and above the inspection target portion A of the electric wire W.
2 are provided.

Hereinafter, a smoke test method using the smoke test apparatus will be described.

First, as in the case of the first embodiment,
The electric wire W is accommodated in the test tank 102 while being stretched in the horizontal direction.

Next, the laser light L is emitted from each laser light source 115 while a predetermined overcurrent is applied to the conductor of the electric wire W by the holding means 110, and the scattered light of the laser light L is monitored by the optical sensor 122.

When smoke is generated from the coating layer of the inspection target portion A at, for example, the longitudinal middle portion of the electric wire W due to the heat generated by the overcurrent, the laser beam L having an optical path corresponding to the place where the smoke is generated is generated. The light is scattered by the smoke, and the scattered light is detected by the optical sensor 122 to detect the smoke.

At this time, the location of the smoke that causes the scattering of the laser light L is located at a position far away from the electric current W or above the electric current W, depending on the magnitude of the overcurrent flowing through the electric wire W. Although a plurality of laser beams L are irradiated above the electric wire W in parallel to each other in a matrix shape while changing positions in the vertical direction and the longitudinal direction of the electric wire W, The light L is scattered by the smoke, and the smoke is accurately detected.

According to the smoke test apparatus configured as described above, the vertical direction and the electric wire W
A plurality of laser light sources 115 are provided in a matrix at different positions in the longitudinal direction, and the laser light L is irradiated in parallel to each other in a horizontal direction orthogonal to the longitudinal direction of the electric wire W. Even if the location of the smoke that causes the scattering of the laser light L due to the magnitude of the overcurrent flowing through the wire fluctuates in the vertical direction and in the longitudinal direction of the electric wire W, any of the laser light L is scattered by the smoke. Can be detected by the optical sensor 122, so that a reliable test result can be obtained even if various smoke tests are performed in which the magnitude of the overcurrent flowing through the electric wire W is different.

Further, since each laser beam L is disposed only above the inspection target portion A of the electric wire W and is irradiated in the horizontal direction perpendicular to the longitudinal direction of the electric wire W, the inspection target portion A of the electric wire W The laser light L is not scattered by smoke generated from other parts, and only the scattered light of the laser light L by smoke generated from the inspection target portion A can be detected. The result can be obtained.

Further, there is no possibility that each laser beam L is attenuated by smoke generated from portions other than the inspection target portion A of the electric wire W before reaching the smoke generated from the inspection target portion A. In this respect, a reliable test result can be obtained.

Finally, a smoke test apparatus according to a fourth embodiment of the present invention will be described with reference to FIGS.

This smoke test apparatus, like the smoke test apparatus of the first embodiment, is configured such that when a certain overcurrent is applied to an electric wire W having a coating layer formed around a conducting wire, smoke is generated from the coating layer. This is for inspecting the characteristics of the electric wire W by measuring the time until the occurrence of the phenomenon, and a pair of holding means 160 is provided on both sides 152 a of the airtight test tank 152. These test tank 152 and holding means 160
Supports the electric wire W with the same configuration as the test tank 2 and the holding means 10 of the first embodiment, and the description thereof is omitted here.

For the same reason as in the first embodiment, the inspection target portion A is set at the middle portion in the longitudinal direction of the electric wire W.

In this smoke test apparatus, the wire W is arranged in a direction perpendicular to the longitudinal direction of the wire W toward the position above the inspection target portion A of the wire W on the side of the disposition position of the wire W, that is, inside the test tank 152. Visible light source 1 for irradiating visible light in a substantially horizontal direction
30 are provided. When smoke is generated from the inspection target portion A by flowing an overcurrent to the electric wire W as described later, the smoke S in the irradiation region P of the light source 130 (the region surrounded by the dashed line in FIG. 5) is illuminated. (A smoke indicated by a bold line in a region surrounded by a dashed line in FIG. 5).

An imaging means 132 such as a CCD camera is provided on the inner side of the test tank 152 and above the visible light source 130. As shown in FIG. 5, the imaging unit 132 captures an image of a region near the inspection target portion A of the electric wire W including the irradiation region P, and smoke S generated from the inspection target portion A is illuminated by visible light as described above. Then, the illuminated portion is configured to be imaged.

The image data obtained by the imaging means 132 is input to the smoke generation detection means 134. The smoke generation detection means 134 includes a binarization processing unit 135 and a determination unit 1
36, and the binarization processing unit 135 includes, among the images obtained by the imaging unit 132,
The image data of the inspection target region Q (the region surrounded by the two-dot chain line in FIG. 5) set so as to include only the position above the image data is binarized by light and dark. Based on the converted image data, the area of the illuminated portion of the smoke S included in the inspection target area Q is obtained, and when it is determined that the area of the illuminated portion is larger than a predetermined value set in advance. It is configured to detect the generation of smoke S from the inspection target portion A and detect the generation of the smoke.

Hereinafter, a smoke test method using this smoke test apparatus will be described. First, similarly to the first embodiment, the electric wire W is housed in the test tank 152 in a state of being stretched in the horizontal direction. .

Next, while passing a certain overcurrent through the conductor of the electric wire W by the holding means 160 and illuminating the position above the inspection object A by the visible light source 130,
At 32, an image of the vicinity of the inspection target portion A is taken and the generation of smoke is monitored.

Then, the electric wire W
Smoke S is generated from the coating layer of the inspection target portion A in the middle portion in the longitudinal direction, and the area of the illuminated portion of the smoke S included in the inspection target region Q in the image captured by the imaging unit 132 has a predetermined value. Is exceeded, the generation of the smoke S is detected by the smoke generation detection means 134.

According to the smoke test apparatus configured as described above, the smoke S included in the inspection target area Q set to include only the position above the inspection target portion A in the image obtained by the imaging means 132. Because smoke is detected based on the image data of the illuminated portion of the electric wire W
, It is possible to detect only smoke generated in the inspection target portion A without being affected by smoke generated from portions other than the inspection target portion A, and to obtain a reliable test result.

In particular, visible light is radiated widely with a predetermined width in the vertical direction above the inspection target portion A at the position above the inspection target portion A, and at the same time, the inspection target region Q of the image data is also irradiated at the position above the inspection target portion A. Because the width is set to have a predetermined width in the vertical direction and wide, the smoke S generated by visible light fluctuates in the vertical direction due to the magnitude of the overcurrent flowing through the electric wire W and the like. It is reliably illuminated by visible light, and the illuminated part is imaged by the imaging means 1.
32, the generation of the smoke S can be detected by the smoke generation detecting means 134, so that even if various smoke tests with different magnitudes of the overcurrent flowing through the electric wires are performed, a reliable test result is obtained. Can be obtained.

[0088]

As described above, according to the smoke test apparatus of the first aspect of the present invention, at least one of the laser light irradiation paths other than the path corresponding to the inspection target portion of the electric wire. The laser light passing through the cylindrical shielding member is not attenuated by smoke generated in a portion other than the inspection target portion of the electric wire, and the laser light passing through the cylindrical shielding member is provided. Since the smoke generated in the inspection target reaches the smoke, sufficient scattered light is obtained by the smoke generated in the inspection target, and the time between the time when the smoke is generated and the time when the scattered light is detected by the smoke is detected. No deviation occurs, and a reliable test result can be obtained.

Further, when the cylindrical shielding member is configured to cover the entire path portion of the laser beam irradiation path except for the path portion corresponding to the inspection target portion of the electric wire, as described in claim 2, Laser light is not scattered by smoke generated from parts other than the inspection target part, and only light scattered by smoke generated at the inspection target part can be detected by the light detection means, and more reliable test results Can be obtained.

Further, when air outside the test tank is passed through the cylindrical shielding member and introduced into the test tank as described in claim 3, for example, smoke may enter the cylindrical shielding member during the test. Even if there is nothing, when the air in the test chamber is ventilated to perform the next test after the test is completed, the smoke is discharged outside the cylindrical shielding member. Even if the test is performed, smoke remaining in the previous test does not affect the next test, and a test with good accuracy can be repeatedly and continuously performed.

According to the smoke test method of the present invention, a laser beam is radiated at a position above the supported electric wire in parallel with the longitudinal direction of the electric wire, and the irradiation path corresponding to the portion to be inspected in the irradiation path. In a state where at least the portion between the laser light source and the corresponding path portion in the path portion excluding the path portion is covered with the cylindrical shielding member, the laser light is irradiated in parallel with the longitudinal direction of the electric wire, so that the inside of the cylindrical shielding member is Laser light passing through the wire does not attenuate due to smoke generated in portions other than the inspection target portion of the electric wire, and reaches the smoke generated in the inspection target portion of the electric wire. Sufficient scattered light is obtained, and there is no deviation between the time when smoke is actually generated and the time when scattered light is detected by the smoke, and a reliable test result can be obtained.

As described in claim 5, the laser beam is covered by the cylindrical shielding member while covering the entire laser beam irradiation path except the path corresponding to the wire inspection target. By irradiating light, laser light is not scattered by smoke generated from parts other than the inspection target part of the electric wire, and only light scattered by smoke generated at the inspection target part is detected by the light detection means. And more reliable test results can be obtained.

Furthermore, if the air outside the test chamber is introduced into the test chamber through the cylindrical shielding member after detecting the smoke generated from the inspection target portion as described in claim 6, for example, Even if smoke enters the tubular shielding member during the test, when the test is completed and the air in the test tank is ventilated for the next test, the smoke Since the smoke is discharged outside, even if this smoke test is performed repeatedly and continuously, the smoke remaining in the previous test does not affect the next test, and a highly accurate test can be repeatedly performed continuously. It becomes possible.

According to the smoke test apparatus of the seventh aspect of the present invention, a plurality of laser light sources are provided at predetermined intervals along the up and down direction above the one end of the electric wire. Since the laser beam is irradiated from the light limit in parallel to the longitudinal direction of the electric wire, the place where smoke that causes laser light scattering due to the magnitude of the overcurrent flowing through the electric wire etc. is considerably far upward from the electric wire Even in the position, even immediately above the wire, one of the laser beams parallel to each other is scattered by the smoke,
This can be detected by the light detecting means. Therefore, even if various smoke tests are performed in which the magnitude of the overcurrent flowing through the electric wire is different, a reliable test result can be obtained.

As described in claim 8, at least a portion between the laser light source and the corresponding path portion among the path portions of the laser light irradiation path by each laser light source except for the corresponding path portion with the inspection target portion of the electric wire. When further provided with a tubular shielding member that covers each, the laser light passing through the tubular shielding member is not attenuated by smoke generated in a portion other than the inspection target portion of the electric wire, and is not affected by smoke generated in the inspection target portion of the electric wire. Smoke generated at the inspection target part will provide sufficient scattered light, and there will be no difference between the time at which the smoke is generated and the time at which the scattered light is detected by the smoke. And reliable test results can be obtained.

Further, as in the smoke test method according to the ninth aspect of the present invention, a plurality of laser light sources are provided at predetermined intervals along the vertical direction at a position above one end of the electric wire. Irradiating a plurality of laser beams parallel to the longitudinal direction of the electric wire at a position above the electric wire and detecting scattered light of each of the laser lights scattered by smoke generated from the electric wire to detect smoke generation When the smoke is generated at a location far away from the electric wire, or close to the top of the electric wire, it is parallel to each other, even if the place where the smoke that causes the scattering of the laser light due to the magnitude of the overcurrent flowing through the electric wire is located. One of the various laser beams is scattered by the smoke, and this can be detected by the light detection means. Even if the test, it is possible to obtain a reliable test result.

Further, according to the smoke test apparatus of the tenth aspect of the present invention, a plurality of laser light sources are provided at predetermined intervals along the vertical direction above the position where the electric wires are disposed, and each of the plurality of laser light sources is disposed in the longitudinal direction of the electric wires. If the laser beam is irradiated in parallel with the horizontal direction perpendicular to the direction, the location where smoke that causes laser beam scattering due to the magnitude of the overcurrent flowing through the wire, etc., is located far upward from the wire. Even
Even in the immediate vicinity of the electric wire, any of the laser beams parallel to each other is scattered by the smoke and can be detected by the light detecting means. Even if various smoke tests different from each other are performed, a reliable test result can be obtained.

Further, since those laser beams are irradiated in a direction perpendicular to the direction in which the electric wires are arranged, it is necessary to reach the smoke generated from the inspected portions of the electric wires before the portions other than the inspected portions of the electric wires. The laser light does not scatter or attenuate the laser light due to the smoke generated from the laser beam, and a reliable test result can be obtained in this regard.

At this time, as described in claim 11,
The laser light sources are arranged in a matrix at a position above the position where the electric wires are arranged, so that the laser light emitted from the laser light sources passes over the electric wires at a plurality of positions along the longitudinal direction of the electric wires. Then, even if the position where smoke is generated fluctuates in the longitudinal direction of the electric wire, it is possible to detect the smoke.

Further, according to the smoke test method according to the twelfth aspect of the present invention, while a predetermined current is applied to the electric wire, the electric wire is provided at a position above the position where the electric wire is provided at predetermined intervals along the vertical direction. In addition to irradiating laser light parallel to the horizontal direction perpendicular to the longitudinal direction of the electric wire from the plurality of laser light sources and detecting the scattered light of each laser light due to smoke generated from the inspection target part, Because the generated smoke is detected, even if the location of the smoke that causes the scattering of laser light due to the magnitude of the overcurrent flowing through the wire is quite far upward from the wire, it is immediately above the wire. Even if it is near, any of the laser beams parallel to each other is scattered by the smoke, and this can be detected by the light detection means, and the overcurrent flowing through the electric wire can be detected. Also comes the like are conducted various smoke testing different, it is possible to obtain reliable test results.

Further, since those laser beams are radiated in parallel to the direction perpendicular to the direction in which the electric wires are arranged, the portions other than the inspection target portions of the electric wires are required to reach the smoke generated from the inspection target portions of the electric wires. The laser light does not scatter or attenuate the laser light due to the smoke generated from the laser beam, and a reliable test result can be obtained in this regard.

As described in claim 13, a plurality of laser light sources are arranged in a matrix above the position where the electric wires are provided, and a plurality of laser light sources are arranged from these laser light sources along the longitudinal direction of the electric wires. When the laser light is irradiated so as to pass above the electric wire, even if the smoke generation position changes in the longitudinal direction of the electric wire, it becomes possible to detect the smoke.

Further, according to the smoke test apparatus of the present invention, the inspection is carried out by irradiating visible light from one side of the arrangement position of the electric wire toward the position above the inspection object portion and energizing the electric wire. A visible light source for illuminating smoke generated from the target portion, imaging means for capturing an image in the vicinity of the inspection target portion including the visible light irradiation region from the same direction as the visible light irradiation direction, Based on the image, the area of the illuminated portion of the smoke included in the image in the predetermined inspection target area set to include only the position above the front inspection target part in the image exceeds a predetermined value. And smoke detection means to detect smoke and detect smoke, so that only smoke generated at the inspection target part is not affected by smoke generated from parts other than the inspection target part of the electric wire. Smoke generation judgment means It is possible to detect, it can be obtained reliable test results.

Further, by irradiating visible light widely above the inspection target portion and setting the inspection target region image vertically above and below the inspection target portion, the magnitude of the overcurrent flowing through the electric wire can be reduced. Even if the location of the smoke illuminated by visible light due to the above is a position far away from the electric wire, or even immediately above the electric wire, the smoke is illuminated by visible light and the illuminated part Can be imaged by the imaging means, and the generation of the smoke can be detected by the smoke generation determination means. Obtainable.

According to the smoke emission test method of the present invention, visible light is irradiated from one side of the position where the electric wire is disposed toward the position above the inspection object portion, and the electric current is applied to the electric wire. Illuminating smoke generated in the inspection target portion, capturing an image of the vicinity of the inspection target portion including the visible light irradiation region from the same direction as the visible light irradiation direction, and an image obtained by the imaging unit. Based on the image, it is detected that the area of the illuminated portion of the smoke included in the image in the predetermined inspection target area set to include only the position above the inspection target portion in the image exceeds a predetermined value. And detecting only the smoke generated in the inspection target part by the smoke generation determination means without being affected by smoke generated from parts other than the inspection target part of the electric wire. Is possible , Can be obtained reliable test results.

Further, by irradiating visible light widely above the inspection target portion and setting the inspection target region image vertically above and below the inspection target portion, the magnitude of the overcurrent flowing through the electric wire can be reduced. Even if the location of the smoke illuminated by visible light due to the above is at a position considerably far upward from the electric wire, or even immediately above the electric wire, the smoke is illuminated by visible light and the illuminated part is The generation of the smoke can be detected by imaging, and a reliable test result can be obtained even if various smoke tests are performed with different magnitudes of the overcurrent flowing through the electric wires.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a smoke test apparatus according to a first embodiment of the present invention.

FIG. 2 is a perspective view showing a smoke test apparatus according to a second embodiment of the present invention.

FIG. 3 is a perspective view showing a smoke test apparatus according to a third embodiment of the present invention.

FIG. 4 is a perspective view showing a smoke test apparatus according to a fourth embodiment of the present invention.

FIG. 5 is a diagram illustrating an image captured by an imaging unit.

FIG. 6 is a perspective view showing a conventional smoke test apparatus.

[Explanation of symbols]

 2 Test tank 10 Holding means 15 Laser light source 20 Cylindrical shielding member 22 Optical sensor A Inspection target part L Laser light W Electric wire

Claims (15)

[Claims] 1. An airtight test tank for accommodating an electric wire in which an inspection target part of a smoke test is set in a middle portion in a longitudinal direction, and the electric wire is stretched horizontally at a predetermined position in the test tank. While supporting in a state, a pair of holding means for flowing a predetermined current through the electric wire, a laser light source for irradiating a laser beam in a longitudinal direction of the electric wire at a position above the electric wire, and Provided at a position capable of detecting the scattered light of the laser light scattered by the smoke generated from the inspection target portion due to the energization of, and detecting the generation of smoke from the inspection target portion by detecting the scattered light. A light-shielding means for covering at least a portion between the laser light source and the corresponding path portion in a path portion of the irradiation path of the laser beam except a corresponding path portion with the inspection target portion of the electric wire. Smoke test apparatus that includes a member. 2. The smoke emission test apparatus according to claim 1, wherein the cylindrical shielding member covers the entire path portion of the laser beam irradiation path except for a path portion corresponding to the inspection target portion of the electric wire. 3. An air introduction means for passing air outside the test chamber through the cylindrical shielding member and introducing the air into the test chamber; and An air exhaust means for exhausting air is provided.
The described smoke test apparatus. 4. A step of supporting an electric wire in which an inspection target part of a smoke test is set at a middle part in a longitudinal direction at a predetermined position in an airtight test tank in a state of being stretched in a horizontal direction, and Flowing a current, and in a state where at least the portion between the laser light source and the corresponding path portion in a path portion of the irradiation path other than the corresponding path portion with the inspection target portion is covered with a cylindrical shielding member, Irradiating the laser light in parallel with the longitudinal direction, and applying the predetermined current to the electric wire and irradiating the laser light in parallel with the longitudinal direction of the electric wire, and the laser light scattered by smoke generated from the electric wire Detecting the smoke by detecting the scattered light of the smoke. 5. The laser beam is radiated by the cylindrical shielding member in a state where the laser beam irradiates the laser beam while covering the entire path of the laser beam except for the path corresponding to the inspection target portion of the electric wire. The smoke test method according to claim 4. 6. After the smoke detection step, air outside the test tank is introduced into the test tank through the cylindrical shielding member, and air is exhausted from the test tank to perform ventilation. The smoke test method according to claim 4 or 5, further comprising a step. 7. An airtight test tank for accommodating an electric wire in which a part to be inspected for a smoke test is set in a middle portion in a longitudinal direction, and the electric wire is stretched horizontally at a predetermined position in the test tank. A pair of holding means for supporting the wire in a state and passing a predetermined current through the wire, and provided at a predetermined interval along the up-down direction at an upper position on one end side of an arrangement position of the wire, and A plurality of laser light sources for irradiating a laser beam parallel to the longitudinal direction of the laser beam; and a laser light source provided at a position where the scattered light of each of the laser beams scattered by smoke generated from the inspection target portion by energizing the electric wire can be detected. And a light detecting means for detecting smoke generated from the inspection target part by detecting the scattered light. 8. A cylindrical shape that covers at least the portion between the laser light source and the corresponding path portion in a path portion of the laser beam irradiation path excluding the corresponding path portion with the inspection target portion of the electric wire from the laser light source. The smoke test apparatus according to claim 7, further comprising a shielding member. 9. A step of supporting an electric wire in which an inspection target part of a smoke test is set at a middle part in a longitudinal direction in a state where the electric wire is horizontally stretched at a predetermined position in an airtight test tank; A step of flowing a current, and a plurality of laser light sources provided at predetermined intervals along the vertical direction at one end side upper position of the arrangement position of the electric wire, each of which is parallel to the longitudinal direction of the electric wire at the upper position of the electric wire. A step of irradiating a plurality of laser lights, and while irradiating a laser beam parallel to a longitudinal direction of the electric wire while applying a predetermined current to the electric wire, any one of the lasers scattered by smoke generated from the electric wire Detecting smoke by detecting scattered light of light. 10. An airtight test tank for accommodating an electric wire in which a part to be inspected for a smoke test is set in an intermediate portion in a longitudinal direction, and the electric wire is stretched horizontally at a predetermined position in the test tank. While supporting in a state, a pair of holding means for flowing a predetermined current through the wire, and provided at a predetermined interval along the up and down direction above the arrangement position of the wire, each of the wire A plurality of laser light sources for irradiating laser light parallel to the horizontal direction orthogonal to the longitudinal direction, and scattered light of each laser light scattered by smoke generated from the inspection target part by energizing the electric wire can be detected. And a light detecting means for detecting smoke generated from the inspection target part by detecting the scattered light thereof. 11. The laser light sources are arranged in a matrix at a position above an arrangement position of the electric wires, and laser light emitted from the laser light sources is provided at a plurality of positions along a longitudinal direction of the electric wires. The smoke test device according to claim 10, wherein the smoke test device passes over the electric wire. 12. A step of supporting an electric wire in which an inspection target part of a smoke test is set at a middle part in a longitudinal direction at a predetermined position in an airtight test tank in a state of being horizontally stretched, and A step of flowing an electric current, and a laser parallel to a horizontal direction orthogonal to the longitudinal direction of the electric wire by a plurality of laser light sources provided at predetermined positions along the vertical direction at a position above the arrangement position of the electric wire. Irradiating the wire with a predetermined current while irradiating the wire with a laser beam parallel to the longitudinal direction of the wire, and scattering each of the laser beams scattered by smoke generated from the wire. Detecting smoke by detecting light. 13. A plurality of laser light sources arranged in a matrix at a position higher than a position at which the electric wire is disposed, and a plurality of laser light sources are arranged at a plurality of positions along the longitudinal direction of the electric wire from these laser light sources. The smoke test method according to claim 12, wherein the passing laser light is applied. 14. An airtight test tank for accommodating an electric wire in which an inspection target part of a smoke test is set in a middle part in a longitudinal direction, and the electric wire is stretched horizontally at a predetermined position in the test tank. While holding in a state, holding means for flowing a predetermined current to the wire, and irradiating visible light from one side of the arrangement position of the wire toward a position above the inspection target portion to the wire A visible light source for illuminating smoke generated from the inspection target portion by energization of the imaging target; and an imaging device for capturing an image near the inspection target portion including the visible light irradiation region from the same direction as the visible light irradiation direction. Means, based on an image obtained by the imaging means, an illuminated portion of smoke contained in a predetermined inspection target area image set to include only the position above the inspection target portion of the electric wire in the image. Area Smoke test apparatus and a smoke generation detection means for detecting the detected and smoke that exceeds a value. 15. A step of supporting an electric wire, in which an inspection target part of a smoke test is set at an intermediate portion in a longitudinal direction, in a state of being horizontally stretched at a predetermined position in an airtight test tank, and Flowing a current, and irradiating visible light from one side of the disposition position of the electric wire toward a position above the inspection target portion to illuminate smoke generated from the inspection target portion by energizing the electric wire. Capturing an image of the vicinity of the inspection target including the irradiation region of the visible light from the same direction as the irradiation direction of the visible light; and applying a predetermined current to the electric wire and at a position above the inspection target. While capturing an image near the inspection target by irradiating visible light, based on an image obtained by the imaging unit, a predetermined image set to include only the position above the inspection target in the image. In the inspection area Smoke test method the area of light out portion of the smoke and a step of detecting smoke by detecting that exceeds a predetermined value contained in the image.