JP2007155384A - Flaw inspection device and flaw inspection method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a flaw inspection device capable of inspecting the flaw of an inner peripheral wall surface in a shorter time, and a flaw inspection method. <P>SOLUTION: The detection pipe inserted in an almost columnar space along with the axial direction of the columnar space and a control device are provided. The incident surface of a light detecting optical fiber is arranged to the leading end of the detection pipe so as to be opposed to the inner peripheral wall surface of the columnar space. The emitting surface of a floodlight projection optical fiber is arranged so as to be adjacent to the incident surface of the light detecting optical fiber in the same direction as the light detecting optical fiber. The control device is constituted so as to relatively rotate the detection pipe, which inputs light to the incident surface of the floodlight projection optical fiber and is inserted along the axial direction of the columnar space, along the circumference of the inner peripheral wall surface of the columnar space or to relatively reciprocate along the axial direction of the columnar space so as to keep the distance up to the opposed of the columnar space from the incident surface of the light detecting optical fiber and the emitting surface of the floodlight optical fiber constant to judge the flaw of the inner peripheral wall surface of the columnar space on the basis of the detection light outputted from the emitting surface of the light detecting optical fiber. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a defect inspection apparatus and a defect inspection method for detecting defects on an inner peripheral wall surface such as a cylinder, a pipe, or a machining hole.

Conventionally, when inspecting a cast hole or a processing flaw on the surface of an inner peripheral wall having a relatively large inner diameter such as a cylinder of a vehicle engine, an image processing apparatus is generally used by inserting a small CCD camera or the like. We are inspecting.
For example, in the prior art described in Patent Document 1, a cleaning unit that cleans residual liquid remaining on the inner surface of a cylindrical object to be inspected such as an engine cylinder, and an optical system that detects a two-dimensional image of the cleaned inner surface are detected. There has been proposed a defect inspection apparatus including an image processing unit that acquires defect information based on a two-dimensional image and an output unit that outputs the acquired defect information.
In the prior art described in Patent Document 2, an imaging means is inserted into the bore of the workpiece to be inspected to image the inner wall surface, image processing is performed to extract a feature parameter, and the extracted parameter value is compared with a reference value. There has been proposed a bore inner wall surface defect inspection apparatus that determines the presence or absence of a defect and sets the actual maximum dimension of the imaged defect candidate as a feature parameter.

In addition, examples of the apparatus for inspecting the inner peripheral wall surface as described above include a magnetic flaw detection apparatus using magnetic field lines, a laser light flaw detection apparatus using laser light, and the like.
For example, in the prior art described in Patent Document 3, a magnetic flaw detector composed of a magnetizer and a magnetic sensor, and a magnetic sensor placed close to a roll on which a metal strip (workpiece) travels, and the rotation of one roll is a period of the magnetic sensor. A metal band magnetic flaw detector that classifies output data obtained by converting a signal from a digital signal into signals and detects the presence or absence of a metal band defect from the difference data between the section data and the next period section data has been proposed. .
JP-A-2005-121450 JP-A-9-311107 JP-A-9-229906

In the conventional technique using the image processing described in Patent Document 1 and Patent Document 2, a CCD camera or a mirror is rotated inside a cylinder. However, illumination light is necessary for imaging, and the CCD camera (or mirror) Similarly, it is necessary to rotate the illumination in the cylinder, and the operation is difficult. Moreover, in order to detect a defect from a captured image, complicated image processing is required, and the time required for inspection is long, and a longer time is required when the detection accuracy is increased. Also, since the internal diameter of the engine cylinder is relatively large, a CCD camera and illumination can be inserted into the cylinder, but in the case of various valve cylinders, brake cylinders, fuel injection nozzles, etc. of the vehicle, the hole diameter is small. It is very difficult to insert the camera and imaging light into the cylinder.
Further, in the prior art using the magnetic flaw detection apparatus described in Patent Document 3, the magnetizer and the magnetic sensor are arranged on the inner wall side and the outer wall side of the cylinder to detect the change in magnetism, so that the engine whose cylinder thickness changes It is very difficult to detect defects with a cylinder or the like.
Further, in the conventional technique using a laser beam flaw detector, the diameter of a spot hit by a laser beam is very small, so that the time required for inspection becomes long.
The present invention has been made in view of such a point, and an object thereof is to provide a defect inspection apparatus and a defect inspection method capable of inspecting a defect on an inner peripheral wall surface in a shorter time.

As means for solving the above-mentioned problems, a first invention of the present invention is a defect inspection apparatus as described in claim 1.
The defect inspection apparatus according to claim 1, wherein the detection pipe inserted into the cylindrical space along the axial direction of the substantially cylindrical space, and the inside of the cylindrical space based on the detection signal from the detection pipe And a control device for determining a defect in the peripheral wall surface.
The detection pipe is provided with a light projecting optical fiber and a light receiving optical fiber. At the tip of the detection pipe, the incident surface of the light receiving optical fiber is opposed to the inner peripheral wall surface of the cylindrical space. Arrange to do.
The emission surface of the light projecting optical fiber is arranged adjacent to the incident surface of the light receiving optical fiber and in the same direction.
The control device inputs light to the incident surface of the light projecting optical fiber, and connects the detection pipe inserted along the axial direction of the cylindrical space to the incident surface of the light receiving optical fiber and the light projecting device. Or relatively rotating along the circumferential direction of the inner circumferential wall surface of the cylindrical space so as to keep a constant distance from each of the exit surfaces of the optical fibers for use to the inner circumferential wall surface of the cylindrical space facing each other, or A defect in the inner peripheral wall surface of the cylindrical space is determined based on detection light output from the emission surface of the light receiving optical fiber by reciprocating relatively along the axial direction.

The second invention of the present invention is a defect inspection apparatus as set forth in claim 2.
The defect inspection apparatus according to claim 2 is the defect inspection apparatus according to claim 1, wherein the detection pipe is provided with a plurality of light projecting optical fibers and a plurality of light receiving optical fibers. At the tip of the detection pipe, the incident surfaces of the plurality of light receiving optical fibers are arranged in a row along the direction parallel to the axis of the cylindrical space so as to face the inner peripheral wall surface of the cylindrical space. Arrange in the direction.
The emission surfaces of the plurality of light projecting optical fibers are arranged in parallel with the light incident optical fiber incident surfaces arranged in the row and in the same direction as the light receiving optical fiber incident surfaces. Deploy.
The control device inputs light to the incident surface of the light projecting optical fiber, and connects the detection pipe inserted along the axial direction of the cylindrical space to each incident surface of the light receiving optical fiber and the projecting light. Relatively along the circumferential direction of the inner peripheral wall surface of the cylindrical space so that the distance from each of the outgoing surfaces of the optical fiber for light to the inner peripheral wall surface of the cylindrical space facing each other is kept constant. It is rotated, and the defect on the inner peripheral wall surface of the cylindrical space is determined based on the detection light output from the emission surface of the light receiving optical fiber.

A third aspect of the present invention is a defect inspection apparatus as set forth in the third aspect.
The defect inspection apparatus according to claim 3 is the defect inspection apparatus according to claim 1, wherein the detection pipe is provided with a plurality of light projecting optical fibers and a plurality of light receiving optical fibers. At the tip of the detection pipe, the incident surfaces of the plurality of light receiving optical fibers are arranged in a row along a direction perpendicular to the axis of the cylindrical space so as to face the inner peripheral wall surface of the cylindrical space. Place in the direction.
The emission surfaces of the plurality of light projecting optical fibers are arranged in parallel with the light incident optical fiber incident surfaces arranged in the row and in the same direction as the light receiving optical fiber incident surfaces. Deploy.
The control device inputs light to the incident surface of the light projecting optical fiber, and connects the detection pipe inserted along the axial direction of the cylindrical space to each incident surface of the light receiving optical fiber and the projecting light. Reciprocally reciprocating along the axial direction so as to keep the distance from each of the emission surfaces of the optical fiber to the inner peripheral wall of the cylindrical space facing each other, A defect on the inner peripheral wall surface of the cylindrical space is determined based on the detection light output from the emission surface.

The fourth invention of the present invention is a defect inspection method as set forth in claim 4.
5. The defect inspection method according to claim 4, wherein a light projecting optical fiber that emits light for detecting a defect on a wall surface toward the wall surface, and a light receiving optical fiber that receives the light reflected from the wall surface. And are used.
The exit surface of the light projecting optical fiber and the entrance surface of the light receiving optical fiber are disposed adjacent to each other in the same direction and facing the wall surface.
Then, light is input to the incident surface of the light projecting optical fiber, the distance from the light emitting surface of the light projecting optical fiber to the wall surface, and the distance from the light incident optical fiber to the wall surface of the light receiving optical fiber. The exit surface of the light projecting optical fiber and the incident surface of the light receiving optical fiber are relatively moved along the wall surface so as to keep the distance constant, and the light incident on the light incident surface of the light receiving optical fiber. This is a defect inspection method for determining a defect on the wall surface based on a change in the intensity of light.

If the defect inspection apparatus according to claim 1 is used, it is only necessary to provide a light projecting optical fiber and a light receiving optical fiber in the detection pipe, so that the diameter of the detection pipe can be made extremely small. It is possible to insert into a small hole. Therefore, it is possible to determine a defect on the inner wall surface of a smaller hole that cannot be inserted with a CCD camera or the like.
In addition, it is possible to determine the defect of the inner peripheral wall surface by rotating relatively along the circumferential direction of the inner peripheral wall surface or relatively reciprocating along the axial direction. Can be done.

  According to the defect inspection apparatus of the second aspect, the incident surfaces of the plurality of light receiving optical fibers are arranged in a line along a direction parallel to the axis (a plurality of emission surfaces of the light projecting optical fibers are also arranged). It is possible to determine a defect with a larger area in a single rotation by relatively rotating along the circumferential direction of the inner peripheral wall surface, and determining the defect in a shorter time. Can do.

  According to the defect inspection apparatus of the third aspect, the incident surfaces of the plurality of light receiving optical fibers are arranged in a line along a direction perpendicular to the axis (a plurality of emission surfaces of the light projecting optical fibers are also arranged). It is possible to determine a defect of a larger area by one slide (outward path or return path) by relatively reciprocating along the axial direction of the inner peripheral wall surface, and in a short time Judgment can be made.

According to the defect inspection method of the fourth aspect of the present invention, it is only necessary to use the light projecting optical fiber and the light receiving optical fiber, so that it can be inserted into a smaller hole. Therefore, it is possible to determine a defect on the inner wall surface of a smaller hole that cannot be inserted with a CCD camera or the like.
In addition, by moving relatively along the wall surface (for example, rotating in the circumferential direction or reciprocating along the axial direction) and determining the defect based on the change in the intensity of the detection light, the time can be shortened, and It is possible to easily determine defects on the inner wall surface.

The best mode for carrying out the present invention will be described below with reference to the drawings. The defect inspection apparatus 1 according to the present invention can be applied to detection of defects (for example, cast holes and machining flaws) on various inner wall surfaces such as cylinders, pipes and machining holes. An example of application to defect detection will be described.
● [Detection pipe structure (FIG. 1A) and overall structure of defect inspection apparatus 1 (FIG. 1B)]
FIG. 1A shows an example of an external view of an embodiment of the detection pipe 10 of the defect inspection apparatus 1 of the present invention, and FIG. 1B shows the overall structure of the defect inspection apparatus 1 of the present invention. An example is shown.
As shown in FIG. 1A, the detection pipe 10 includes a detection unit 13, an insertion unit 11, a support unit 12, a flexible tube 14, an attachment unit 15, and the like.
In the detection unit 13, the emission surface of the light projecting optical fiber 13a and the incident surface of the light receiving optical fiber 13b are arranged in a predetermined direction (see FIGS. 2A and 3A). The detection unit 13 is provided at the distal end of the insertion unit 11, and the insertion unit 11 is inserted along the axial direction of a substantially cylindrical space to be inspected. The insertion section 11 accommodates a bundle of light projecting optical fibers 13a and light receiving optical fibers 13b. The bundle of light projecting optical fibers 13a and light receiving optical fibers 13b is externally connected by a flexible tube 14. Has been drawn to.

An attachment portion 15 (attachment screw or the like) is fixed to the support portion 12. As shown in FIG. 1B, the mounting portion 15 is fixed to the tool T, and the tool T moves the detection pipe 10 relatively reciprocally along the axis ZS of the cylinder S inside the cylinder S, or the cylinder S Is relatively rotated along the circumferential direction of the inner peripheral wall surface. Therefore, the detection pipe 10 may be moved, or the cylinder S may be moved.
The length LH in the longitudinal direction of the insertion portion 11 is set according to the length of the inner peripheral wall surface of the cylindrical space to be inspected, and the diameter φ of the insertion portion 11 is set to the inner peripheral wall surface of the cylindrical space to be inspected. It is set according to the diameter. The diameters of the light projecting optical fiber 13a and the light receiving optical fiber 13b are, for example, about 0.2 [mm] to 0.5 [mm]. The diameter φ of 11 is sufficiently within a few [mm]. Therefore, the insertion portion 11 can be inserted even with a hole having a relatively small diameter of about several mm, which is difficult to insert a CCD camera or the like.
The length LZ of the detection unit 13 in the Z-axis direction is set as appropriate.

As shown in FIG. 1B, the defect inspection apparatus 1 according to the present invention includes a detection pipe 10 and a control device 30. The control device 30 includes, for example, a personal computer 23 (hereinafter referred to as a personal computer 23), a signal processing unit 21, a driving unit 22, and the like.
The signal processing means 21 is connected to the detection pipe 10 and the flexible tube 14, and supplies light irradiated from the emission surface of the light projecting optical fiber 13 a of the detection unit 13 based on a control signal from the personal computer 23. The detection light incident on the incident surface of the light receiving optical fiber 13 b of the detection unit 13 is received, and the detected detection signal is transmitted to the personal computer 23. The personal computer 23 determines the presence / absence of a defect based on the detection signal input from the signal processing means 21.
The driving means 22 rotates or slides (reciprocates) the tool T based on a control signal from the personal computer 23. Note that the cylinder S may be rotated or slid.

[First Embodiment (FIGS. 2 and 4)]
Next, the first embodiment will be described with reference to FIGS. 2A to 2C and FIG.
The insertion portion 11 of the detection pipe 10 accommodates a plurality of light receiving optical fibers 13b and a plurality of light projecting optical fibers 13a.
As shown in FIG. 2A, in the first embodiment, the incident surfaces of the light receiving optical fibers 13b arranged in the detector 13 are arranged in a line along a direction parallel to the axis ZS of the cylinder S. Is arranged. The incident surface of the light receiving optical fiber 13b is directed so as to face the inner peripheral wall surface of the cylindrical space, and the respective incident surfaces are directed in the same direction.
Further, the emission surface of the light projecting optical fiber 13a is arranged in parallel with the incident surface of the light receiving optical fiber 13b arranged in a row, and each light emitting surface is connected to the incident surface of the light receiving optical fiber 13b. They are oriented in the same direction. In the example shown in FIG. 2A, the incident surface of the light receiving optical fiber 13b has one row and the exit surface of the light projecting optical fiber 13a has two rows. However, the number is not limited to this number. Absent.

Next, a procedure for detecting a defect on the inner peripheral wall surface of the cylinder S will be described with reference to FIGS.
When detecting a defect on the inner peripheral wall surface of the cylinder S, the insertion portion 11 is first inserted into the cylinder S along the axis ZS of the cylinder S. At the inserted position, the distance GA between each of the emission surfaces of the light projecting optical fiber 13a and each of the incident surfaces of the light receiving optical fiber 13b and the inner peripheral wall surface of the opposing cylinder S is set to a predetermined distance (for example, 1.5). (Mm) to an appropriate value within the range of 3.5 [mm] (see FIG. 2B).
As shown in FIG. 4, the control device 30 includes a light source 31, a signal conversion unit 32, a signal amplification unit 33, a filter unit 34, a determination unit 35, and the like (note that the drive unit 22 is not shown).
The control device 30 uses the light source 31 to cause light to enter the incident surface of the light projecting optical fiber 13a. For example, an LED is used as the light source 31, and visible red light is incident on the incident surface of the light projecting optical fiber 13a.

Furthermore, the control device 30 rotates the insertion portion 11 along the circumferential direction of the inner peripheral wall surface of the cylinder S so as to keep the distance GA constant by using the driving means 22 (see FIG. 2B). In addition, since the flexible tube 14 is pulled out from the insertion part 11, it is preferable to make the rotation direction alternate, for example, to make one rotation in the counterclockwise direction after making one rotation in the clockwise direction.
And the control apparatus 30 detects the defect of the internal peripheral wall surface of the cylinder S based on the detection light output from the output surface of the optical fiber 13b for light reception, rotating the insertion part 11. FIG.

As shown in FIG. 4, the detection light output from the exit surface of the light receiving optical fiber 13b is input to the signal conversion means 32 and converted into an electrical signal. The converted electrical signal is input to the signal amplifying means 33 and amplified, and when the high-frequency noise component is removed by the filter means 34 (low-pass filter or the like) and a defect signal is detected by the judging means 35, there is a defect. Is determined.
When there is no defect on the inner peripheral wall surface, a part of the light that is emitted from the emission surface 13aout of the light projecting optical fiber 13a and reflected from the inner wall surface M is received as shown by the one-dot chain circle in FIG. The light is incident on the incident surface 13bin of the optical fiber 13b, and the intensity of the light becomes substantially constant. However, when there is a defect (such as a cast hole or a processing flaw), irregular reflection occurs on the inner wall surface M of the defective portion, so that the intensity of light incident on the incident surface 13bin is reduced.
The determination means 35 is provided with a predetermined threshold (Vth in FIG. 4), and determines a signal (sg1 in FIG. 4) equal to or lower than the threshold as a defect.

For example, in the case of a cylinder having a relatively large inner diameter, such as an engine cylinder of a vehicle, the diameter φ of the insertion portion 11 can be made relatively large. Therefore, the number of light projecting optical fibers 13a and light receiving optical fibers 13b can be increased, and the detection portion 13 can increase the number of exit surfaces and entrance surfaces (the length LZ of the detector 13 in FIG. 2A can be increased).
For this reason, it is possible to detect the entire circumference of the cylinder inner peripheral wall surface only by rotating the detection unit 13 once along the circumferential direction of the cylinder inner peripheral wall surface. No stable automatic inspection is possible.
When the length of the cylinder inner peripheral wall surface in the longitudinal direction is longer than the length LZ of the detection unit 13, first, the detection unit 13 is rotated once to inspect the inner peripheral wall surface with the width of the detection unit 13 length LZ. This is repeated until the length of the inner circumferential wall surface of the cylinder reaches the length in the longitudinal direction.
Note that if a plurality of detection units 13 are provided as shown in the example of FIG. 2C, the inspection time can be further shortened (in the example of FIG. 2C, there is no need to rotate 360 °). , 180 ° rotation is sufficient).

[Second Embodiment (FIGS. 3 and 4)]
Next, a second embodiment will be described with reference to FIGS. 3 (A) to 3 (C) and FIG.
The second embodiment is different from the first embodiment in the arrangement direction of the incident surfaces of the plurality of light receiving optical fibers 13b and the emission surfaces of the plurality of light projecting optical fibers 13a in the detection unit 13. And the moving direction of the insertion part 11 after inserting the insertion part 11 in the cylinder S is different. Hereinafter, differences from the first embodiment will be described.

As shown in FIG. 3A, in the second embodiment, the incident surfaces of the light receiving optical fibers 13b arranged in the detector 13 are arranged in a line along a direction perpendicular to the axis ZS of the cylinder S. Has been placed. The incident surface of the light receiving optical fiber 13b is directed so as to face the inner peripheral wall surface of the cylindrical space, and the respective incident surfaces are directed in the same direction.
Further, the emission surface of the light projecting optical fiber 13a is arranged in parallel with the incident surface of the light receiving optical fiber 13b arranged in a row, and each light emitting surface is connected to the incident surface of the light receiving optical fiber 13b. They are oriented in the same direction. In the example shown in FIG. 3A, the incident surface of the light receiving optical fiber 13b has one row and the exit surface of the light projecting optical fiber 13a has two rows. However, the number is not limited to this number. Absent.

Next, a procedure for detecting a defect on the inner peripheral wall surface of the cylinder S will be described with reference to FIG. Since the configuration of the control device 30 shown in FIG. 4 is the same as that of the first embodiment, description thereof is omitted.
When detecting a defect on the inner peripheral wall surface of the cylinder S, the insertion portion 11 is first inserted into the cylinder S along the axis ZS of the cylinder S. At the inserted position, a distance GB between each of the emission surfaces of the light projecting optical fiber 13a and each of the incident surfaces of the light receiving optical fiber 13b and the inner peripheral wall surface of the opposing cylinder S is a predetermined distance (for example, 1.5). It is set to be an appropriate value within the range of [mm] to 3.5 [mm] (see FIG. 3B).
The control device 30 uses the light source 31 to cause light to enter the incident surface of the light projecting optical fiber 13a.
Further, the control device 30 slides (reciprocates) the insertion portion 11 along the axial direction (the direction of the axis ZS) of the inner peripheral wall surface of the cylinder S so as to keep the distance GB constant by using the driving means 22 (FIG. 3 (B)).
And the control apparatus 30 detects the defect of the internal peripheral wall surface of the cylinder S based on the detection light output from the output surface of the optical fiber 13b for light reception, sliding the insertion part 11 (reciprocating).

For example, in a mission valve cylinder, a brake cylinder, an injection nozzle hole, etc. of a vehicle (automobile, motorcycle, etc.), the inner diameter must be small (for example, about several [mm]) and the diameter of the insertion portion 11 must be small. In addition, the number of light receiving optical fibers is reduced, and the detectable width (the width LY of the detection unit 13 in FIG. 3A) is also reduced.
However, in the second embodiment, an inspection is performed such that the cylinder is slid in the longitudinal direction of the cylinder with the detection width of LY (forward path), is rotated to the undetected peripheral portion, and is slid in the longitudinal direction (return path). Repeat until reaching the entire circumference of the wall.
If a plurality of detection units 13 are provided as shown in the example of FIG. 3C, the inspection time can be further shortened.
In this way, it is possible to greatly reduce the inspection time and perform stable automatic inspection without relying on visual observation.

● [Third embodiment]
In the embodiment described above, the emission surface of the light projecting optical fiber 13a and the incident surface of the light receiving optical fiber 13b arranged in the detection unit 13 are arranged in a row. Good. The number of light projecting optical fibers 13a and light receiving optical fibers 13b may be singular or plural.
In short, the emitting surface of the light projecting optical fiber 13a and the incident surface of the light receiving optical fiber 13b are arranged adjacent to each other in the same direction and face the inner wall surface of the inspection object, and the light projecting optical fiber 13a enters. Light may be incident on the surface and moved so as to pass through the entire inner wall surface while keeping the distance from the inner wall surface constant.
Even if the moving direction is slid in the axial direction or rotated in the circumferential direction, it may be moved in any direction as long as the distance from the inner wall surface is kept constant. Therefore, the inspection target may not be a cylindrical inner wall.
Then, the defect of the inner wall surface is determined based on the change in the intensity of the light output from the emission surface of the light receiving optical fiber 13b.
In order to perform the inspection in a shorter time, a plurality of emission surfaces and incident surfaces (the emission surface of the light projecting optical fiber 13a and the incident surface of the light receiving optical fiber 13b) along a direction perpendicular to the moving direction. ) Is preferably arranged.

The defect inspection apparatus 1 of the present invention is not limited to the appearance, configuration, inspection procedure and the like described in the present embodiment, and various modifications, additions, and deletions can be made without changing the gist of the present invention.
The numerical values used in the description of the present embodiment are examples, and are not limited to these numerical values.

  The defect inspection apparatus 1 of the present invention is not limited to the cylinder described in the present embodiment, such as an engine cylinder and a brake cylinder of a vehicle, but is used to detect defects on the inner peripheral wall surface such as various cylinders, pipes, and machining holes. It is possible to apply.

It is a figure explaining one Embodiment of the structure of the defect inspection apparatus 1 of this invention, and the structure of the detection pipe 10 which comprises the defect inspection apparatus 1. FIG. It is a figure explaining the structure and defect inspection procedure of the detection part 13 in 1st Embodiment. It is a figure explaining the structure and defect inspection procedure of the detection part 13 in 2nd Embodiment. It is a figure explaining the example of the structure of the control apparatus 30, and the determination method of a defect.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Defect inspection apparatus 10 Detection pipe 11 Insertion part 12 Support part 13 Detection part 13a Light-emitting optical fiber 13b Light-receiving optical fiber 14 Flexible tube 15 Mounting part 21 Signal processing means 22 Drive means 23 Personal computer 30 Control apparatus 31 Light source 32 Signal Conversion means 33 Signal amplification means 34 Filter means 35 Determination means S Cylinder ZS axis

Claims (4)

A detection pipe inserted into the cylindrical space along the axial direction of the substantially cylindrical space, and a control device for determining a defect on the inner peripheral wall surface of the cylindrical space based on a detection signal from the detection pipe. Prepared,
The detection pipe is provided with a light projecting optical fiber and a light receiving optical fiber,
At the tip of the detection pipe, the incident surface of the light receiving optical fiber is disposed so as to face the inner peripheral wall surface of the cylindrical space,
The emission surface of the light projecting optical fiber is arranged so as to be adjacent to the incident surface of the light receiving optical fiber and in the same direction,
The controller is
Light is input to the incident surface of the light projecting optical fiber,
The detection pipe inserted along the axial direction of the cylindrical space is connected to each of the incident surface of the light receiving optical fiber and the output surface of the light projecting optical fiber to the inner peripheral wall surface of the cylindrical space facing each other. In order to keep the distance constant, it is relatively rotated along the circumferential direction of the inner circumferential wall surface of the cylindrical space or relatively reciprocated along the axial direction, and output from the emission surface of the light receiving optical fiber. Determining a defect on the inner peripheral wall surface of the cylindrical space based on the detected light to be
A defect inspection apparatus characterized by that. The defect inspection apparatus according to claim 1,
The detection pipe is provided with a plurality of light projecting optical fibers and a plurality of light receiving optical fibers,
At the tip of the detection pipe, the incident surfaces of the plurality of light receiving optical fibers are arranged in a row along the direction parallel to the axis of the cylindrical space so as to face the inner peripheral wall surface of the cylindrical space. Place in the direction,
The emission surfaces of the plurality of light projecting optical fibers are arranged so as to be in parallel with the incident surface of the light receiving optical fibers arranged in a row and in the same direction as the light receiving optical fiber. And
The controller is
Light is input to the incident surface of the light projecting optical fiber,
The detection pipe inserted along the axial direction of the columnar space has an inner peripheral wall surface of the columnar space facing each incident surface of the light receiving optical fiber and each light emitting surface of the light projecting optical fiber. In order to keep the distance to each constant, relatively rotate along the circumferential direction of the inner wall surface of the cylindrical space, based on the detection light output from the emission surface of the light receiving optical fiber Determining defects on the inner wall surface of the cylindrical space,
A defect inspection apparatus characterized by that. The defect inspection apparatus according to claim 1,
The detection pipe is provided with a plurality of light projecting optical fibers and a plurality of light receiving optical fibers,
At the tip of the detection pipe, the incident surfaces of the plurality of light receiving optical fibers are arranged in a row along a direction perpendicular to the axis of the cylindrical space so as to face the inner peripheral wall surface of the cylindrical space. Place in the direction,
The emission surfaces of the plurality of light projecting optical fibers are arranged so as to be in parallel with the incident surface of the light receiving optical fibers arranged in a row and in the same direction as the light receiving optical fiber. And
The controller is
Light is input to the incident surface of the light projecting optical fiber,
The detection pipe inserted along the axial direction of the columnar space has an inner peripheral wall surface of the columnar space facing each incident surface of the light receiving optical fiber and each light emitting surface of the light projecting optical fiber. In order to keep the distance to each constant, the defect of the inner peripheral wall surface of the cylindrical space is reciprocated relatively along the axial direction and based on the detection light output from the emission surface of the light receiving optical fiber Determine
A defect inspection apparatus characterized by that. Using a light projecting optical fiber that emits light for detecting defects on the wall surface toward the wall surface, and a light receiving optical fiber that receives the light reflected from the wall surface,
An emission surface of the light projecting optical fiber and an incident surface of the light receiving optical fiber are disposed adjacent to each other in the same direction and facing the wall surface,
Light is input to the incident surface of the light projecting optical fiber, the distance from the light emitting surface of the light projecting optical fiber to the wall surface, and the distance from the light incident optical fiber to the wall surface of the light receiving optical fiber. So that the light exiting optical fiber and the light receiving optical fiber incident surface are relatively moved along the wall surface and are incident on the light receiving optical fiber incident surface. Determining defects in the wall surface based on changes in light intensity;
A defect inspection method characterized by that.

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