JP2007033276A - Inspection apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To realize an inspection apparatus with a simple structure capable of reducing fluctuations in brightness due to photographing positions and detecting a defect accurately. <P>SOLUTION: The inspection apparatus comprises: a light guiding member 5 for transmitting illumination light to the inner peripheral surface of an object to be inspected; an image transmission member 2 which is arranged so as to be able to move relative to the object to be inspected along the inner peripheral surface of the object to be inspected; a photographing means 3 which photographs the inner peripheral surface of the object to be inspected by receiving light transmitted from the inner peripheral surface of the object to be inspected through the image transmission member 2; a defect detecting means 10 which detects the defect by using a plurality of images photographed by the photographing means 3; and a reflection reducing plate 8 which absorbs at least a portion of light other than light heading toward the image transmission member 2 from the inner peripheral surface of the object to be inspected. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an inspection apparatus, and more particularly to an inner surface defect inspection apparatus such as a small-diameter hole formed in a component of an automobile, for example, a control hole of a hydraulic valve.

For inspection of castholes and defects generated on the inner surface of a small-diameter hole, the borescope's field of view is bent 90 ° around the entire inner wall surface with a conical mirror so that images can be taken from the direction perpendicular to the inner wall surface. (For example, refer to Patent Document 1).
In addition, the captured image is inspected for inner surface defects by linearly transforming a region cut out in a circular shape from each image captured in time series and expanding it into a two-dimensional image (for example, Patent Document 2).

Japanese Patent Laid-Open No. 6-18246 (2nd page, FIG. 5) JP-A-6-241760 (page 2-3, FIG. 2-3)

When inspecting the inner surface of a hole with a conventional inspection device, the cone mirror is arranged facing the scope, so the smaller the diameter of the hole, the more the irradiation angle of the illumination becomes parallel to the depth direction of the hole. Since it is difficult to remove the reflection of the image, there is a problem that it becomes difficult to detect the defect.
In addition, in the case of a direct-view inspection optical system with the conical mirror removed, the light reflected from the bottom surface enters the scope via the inner wall surface, so the image becomes brighter as the imaging position approaches the bottom surface and moves away from the bottom surface. Since the image becomes darker, processing such as adjusting the illumination intensity according to the imaging position is necessary.

  The present invention has been made to solve the above-described problems, and an object of the present invention is to obtain an inspection apparatus that can accurately detect defects by reducing brightness fluctuations depending on an imaging position with a simple configuration.

  The inspection apparatus according to the present invention is disposed such that a light guide member that transmits illumination light to an inner peripheral surface of an inspection target and a relative movement with respect to the inspection target along the inner peripheral surface of the inspection target. An image transmission member, an imaging unit that images the inner peripheral surface of the inspection target with light transmitted from the inner peripheral surface of the inspection target via the image transmission member, and a plurality of images captured by the imaging unit And a light detection member that absorbs at least part of light other than light directed from the inner peripheral surface of the inspection target to the image transmission member.

  According to the present invention, it is possible to obtain an inspection apparatus capable of accurately detecting a defect by reducing brightness fluctuations depending on an imaging position with a simple configuration.

Embodiment 1 FIG.
A first embodiment of the present invention will be described with reference to FIGS. FIG. 1 is a block diagram showing a configuration in the first embodiment. FIG. 2 is an explanatory diagram showing an image expansion operation in the first embodiment. FIG. 2A shows an original image, and FIG. 2B shows a developed image.

In FIG. 1, an object 1 to be measured, which is a hydraulic valve having small holes (hereinafter referred to as inspection target holes) such as a large number of control holes to be inspected as components of an automobile, is held by a holder 13. The holder 13 is attached in advance with a reduced reflection plate 8 made of a light absorbing material extending in a direction perpendicular to the inner peripheral surface of the hole to be inspected. This reduced reflection plate 8 is used to inspect the object 1 to be measured. It is configured to be inserted into an oil flow path provided at the bottom of a control hole in a hydraulic valve as a target hole.
The endoscope 6 constituted by the image transmission member 2, the image pickup means 3, the illumination means 4, and the light guide member 5 is a small hole that forms a control hole in a hydraulic valve that is an inspection target hole of the measured object 1. It is fixed to the moving table 7 so that it can move back and forth in the depth direction.
The image expanding means 9 expands the cylindrical inner surface image on the inner peripheral surface of the inspection target hole imaged by the imaging means 3 into a two-dimensional plane image while the endoscope 6 moves in the depth direction. The defect detection means 10 performs various image processing on the image developed by the image development means 9 to detect defects on the inner peripheral surface of the inspection target hole.

Next, the operation will be described.
The object 1 to be measured is held by the holder 13 and is transported to the inspection position by transport means (not shown). The holder 13 is previously attached with a reflection reducing plate 8 in accordance with the position of the opening at the bottom of the hole to be inspected in the object 1 to be measured, and is reduced when the object 1 to be measured is held by the holder 13. The reflector 8 extends in a direction perpendicular to the inner peripheral surface of the inspection target hole and is inserted into the bottom of the inspection target hole.
When the measured object 1 is positioned at the specified position, the endoscope 6 starts moving toward the measured object 1 by the moving table 7. A part of the light emitted from the illumination unit 4 through the cylindrical light guide member 5 is scattered on the cylindrical inner surface of the inner peripheral surface of the inspection target hole, but most of the light is directed toward the bottom surface of the inspection target hole. Reflected and travels towards the bottom. The light reflected by the cylindrical inner surface of the inner peripheral surface of the inspection target hole and reaching the bottom surface of the inspection target hole is absorbed by the anti-reflection plate 8.

The imaging means 3 performs an imaging operation via the image transmission member 2 by the light irradiated by the illumination means 4 via the light guide member 5 and scattered by the cylindrical inner surface of the inner peripheral surface of the inspection target hole. An image of the inner peripheral surface of the inspection target hole as shown in a) is picked up so as to generate n circular images at the same transport pitch. The n circular images picked up by the image pickup means 3 are transferred to the image expansion means 9.
The image expansion means 9 cuts out each ring-shaped area (A-B) from the n images transferred from the image pickup means 3, and converts the cut-out circular area into a linear shape and develops it into a two-dimensional image. Thus, a two-dimensional developed image of the inner peripheral surface in the inspection target hole as shown in FIG.
The defect detection means 10 performs various image processing on the two-dimensional image developed by the image development means 9, extracts defect candidates, and determines the presence or absence of defects.

  By configuring as described above, the image obtained by the imaging means 3 is not affected by the reflected light from the bottom surface in the inspection target hole, and therefore, images with little brightness fluctuation can be continuously collected, and a good quality inner surface is obtained. A developed image can be obtained. Therefore, an effect of improving S / N for defect detection can be obtained.

In this embodiment, the endoscope 6 is configured to move on the moving table 7, but may be configured to move the measured object 1.
In this embodiment, the anti-reflection plate 8 is mounted on the holder 13 in advance and configured to move together with the holder 13 to the inspection position, but may be configured to be inserted by machining or the like at the inspection position. .

  According to the first embodiment of the present invention, the illumination light is applied to the inner peripheral surface of the small hole as the inspection target hole in the inspection target composed of the measured object 1 such as a hydraulic valve having a large number of control holes as a component of the automobile. The light guide member 5 to be transmitted is arranged so as to be relatively movable with respect to the inspection object made of the measurement object 1 along the inner peripheral surface of the small hole as the inspection object hole in the inspection object made of the measurement object 1. An image transmission member 2 provided and the object to be measured 1 by light transmitted through the image transmission member 2 from an inner peripheral surface of a small hole as an inspection object hole in the inspection object composed of the object 1 to be measured. An imaging means 3 for imaging an inner peripheral surface of a small hole as an inspection target hole in the inspection target, and a small as an inspection target hole in the inspection target consisting of the measured object 1 imaged by the imaging means 3 Image developing means 9 for developing the inner peripheral surface image into a plurality of two-dimensional planar images, and defect detecting means 10 for detecting defects from the plurality of two-dimensional planar images captured by the imaging means 3. The light adjusting member comprising the anti-reflection plate 8 that absorbs at least a part of light other than the light traveling from the inner peripheral surface of the small hole as the inspection target hole in the inspection target made of the measured object 1 to the image transmission member 2 Is fixed relative to the inspection object consisting of the object 1 to be measured, and the light adjustment member is fixed relative to the inspection object, thereby providing brightness according to the imaging position with a simple configuration. It is possible to obtain a small-diameter hole inner peripheral surface inspection apparatus that can reduce fluctuations and accurately detect defects.

  Further, according to the first embodiment of the present invention, the inner peripheral surface of the small hole as the inspection target hole in the inspection target consisting of the object to be measured 1 such as a hydraulic valve having a large number of control holes as a component of the automobile is illuminated. The light guide member 5 that transmits light and the inspection object made of the object to be measured 1 can move relative to the inner peripheral surface of the small hole as the inspection object hole in the inspection object made of the object to be measured 1. And the inspection object consisting of the object to be measured 1 by the light transmitted through the image transmission member 2 from the inner peripheral surface of the small hole in the inspection object consisting of the object to be measured 1 Imaging means 3 for imaging the inner peripheral surface of the small hole as the inspection target hole in the inspection object, and the inner peripheral surface of the small hole as the inspection target hole in the inspection target consisting of the measured object 1 imaged by the imaging means 3 An image development means 9 for developing an image into a plurality of two-dimensional plane images; and a defect detection means 10 for detecting a defect based on the plurality of two-dimensional plane images picked up by the image pickup means 3. 1 covers the bottom surface of the small hole as the inspection target hole in the inspection target consisting of the measured object 1 connected to the inner peripheral surface of the small hole as the inspection target hole in the inspection target consisting of 1 from the inner peripheral surface of the inspection target Since the light adjustment member composed of the anti-reflection plate 8 that absorbs at least a part of the light other than the light directed to the image transmission member is disposed relatively fixed to the inspection object composed of the object to be measured 1, By arranging the light adjustment member covering the bottom surface relatively fixed to the inspection object, a small diameter hole inner peripheral surface inspection device capable of accurately detecting defects by reducing the brightness fluctuation due to the imaging position with a simple configuration is obtained. Can That.

Embodiment 2. FIG.
A second embodiment according to the present invention will be described with reference to FIGS. FIG. 3 is a block diagram showing a configuration in the second embodiment. FIG. 4 is an explanatory diagram showing an image expansion operation in the second embodiment. 4A shows the original image, and FIG. 4B shows the developed image. FIG. 5 is a block diagram showing another configuration in the second embodiment.
In the second embodiment, the configuration other than the specific configuration described here has the same configuration contents as the configuration in the first embodiment described above, and exhibits the same operation. In the drawings, the same reference numerals indicate the same or corresponding parts.

In the configuration of the first embodiment shown in FIG. 1, the antireflection plate is inserted into the bottom of the hole to be inspected. In the second embodiment, as shown in FIG. 3, an endoscope is used. A disc-shaped anti-reflection plate 11a extending in a direction perpendicular to the inner peripheral surface of the inspection object hole is fixed to the front surface of 6.
At the front end of the image transmission member 2 provided on the front surface of the endoscope 6 (see FIG. 1), a disk-shaped anti-reflection plate 11a made of a anti-reflection material via a rod-like support portion SP made of an anti-reflection material. Is provided so as to extend in a direction perpendicular to the inner peripheral surface of the hole to be inspected.
In this case, as shown in FIG. 4A, the field of view of the cut-out area is not blocked by the anti-reflection plate 11a, and is captured without being affected by the generation of the developed image shown in FIG. Can be performed.

The shape of the reduced reflection plate may be a conical shape or a curved shape like the reduced reflection plate 11b shown in FIG.
As shown in FIG. 5, the anti-reflection plate 11b has a rod-like shape made of a anti-reflection material at the tip of the image transmission member 2 provided on the front surface of the endoscope 6, like the anti-reflection plate 11a shown in FIG. A disc-shaped anti-reflection plate 11b made of an anti-reflection material is provided so as to extend in a direction perpendicular to the inner peripheral surface of the inspection target hole via the support portion SP. The back surface of the anti-reflection plate 11b connected to the support portion SP is formed in a conical shape having a relatively low height. The back surface shape of the reduced reflection plate 11b may be a shape other than the conical shape such as a curved surface shape bulging from the conical shape.

  By configuring as described above, there is an effect that the work of exchanging the holding tool 13 becomes unnecessary when changing the type of the object 1 to be measured.

  According to the second embodiment of the present invention, the illumination light is applied to the inner peripheral surface of the small hole as the inspection target hole in the inspection target composed of the measured object 1 such as a hydraulic valve having a large number of control holes as a component of the automobile. The light guide member 5 to be transmitted is arranged so as to be relatively movable with respect to the inspection object made of the measurement object 1 along the inner peripheral surface of the small hole as the inspection object hole in the inspection object made of the measurement object 1. An image transmission member 2 provided and the object to be measured 1 by light transmitted through the image transmission member 2 from an inner peripheral surface of a small hole as an inspection object hole in the inspection object composed of the object 1 to be measured. The inspection object in the inspection object consisting of the imaging means 3 (see FIG. 1) for imaging the inner peripheral surface of the small hole as the inspection object hole in the inspection object, and the measured object 1 imaged by the imaging means 3 The image development means 9 (see FIG. 1) that develops the image of the inner peripheral surface of the small hole into a plurality of two-dimensional planar images, and the defects by the plurality of two-dimensional planar images imaged by the imaging means 3 A defect detection means 10 (see FIG. 1) for detecting, and at least a portion other than light directed from the inner peripheral surface of a small hole as an inspection target hole in the inspection target made of the measured object 1 to the image transmission member 2 A light adjusting member composed of a disk-like reduced reflection plate 11a or a reduced reflection plate 11b that absorbs the light of the image is perpendicular to the inner peripheral surface of the hole to be inspected via a rod-like support portion SP at the tip of the image transmission member 2. Since the light transmitting member is fixedly disposed relative to the image transmitting member 2 so as to extend, the light adjustment member is disposed relatively fixed to the image transmitting member. Reduces fluctuations and accurately detects defects Kill it is possible to obtain a small-diameter hole inner peripheral surface inspection apparatus enable easy replacement of the inspection object change.

Embodiment 3 FIG.
A third embodiment of the present invention will be described with reference to FIG. FIG. 6 is a block diagram showing a configuration in the third embodiment.
In the third embodiment, the configuration other than the specific configuration described here has the same configuration contents as the configuration in the second embodiment described above, and exhibits the same operation. In the drawings, the same reference numerals indicate the same or corresponding parts.

In the configuration of the second embodiment shown in FIGS. 3 and 5, the anti-reflection plate 11a is provided by the support portion SP attached to the front end of the image transmission member 2 provided on the front surface of the endoscope 6 (see FIG. 1). 11b is fixed, but in the third embodiment, as shown in FIG. 6, the anti-reflection is fixed to the image transmission member 2 by the support portion SP attached to the front end of the image transmission member 2. A part of the plate 12 is an illumination light diffusion plate 12a.
The illumination light diffusing plate 12a is a disk-shaped member that extends in a direction perpendicular to the inner peripheral surface of the inspection target hole and is disposed on the reduced reflection plate 12, and diffuses the illumination light inside the inspection target hole. Consists of diffusion means.

  With this configuration, it is possible to increase the amount of light that contributes to imaging, and to obtain an effect of suppressing the illumination power.

  According to the third embodiment of the present invention, the illumination light is applied to the inner peripheral surface of the small hole as the inspection target hole in the inspection target composed of the object to be measured 1 such as a hydraulic valve having a large number of control holes as a component of the automobile. The light guide member 5 to be transmitted is arranged so as to be relatively movable with respect to the inspection object made of the measurement object 1 along the inner peripheral surface of the small hole as the inspection object hole in the inspection object made of the measurement object 1. An image transmission member 2 provided and the object to be measured 1 by light transmitted through the image transmission member 2 from an inner peripheral surface of a small hole as an inspection object hole in the inspection object composed of the object 1 to be measured. The inspection object in the inspection object consisting of the imaging means 3 (see FIG. 1) for imaging the inner peripheral surface of the small hole as the inspection object hole in the inspection object, and the measured object 1 imaged by the imaging means 3 The image development means 9 (see FIG. 1) that develops the image of the inner peripheral surface of the small hole into a plurality of two-dimensional planar images, and the defects by the plurality of two-dimensional planar images imaged by the imaging means 3 A defect detection means 10 (see FIG. 1) for detecting, and at least a portion other than light directed from the inner peripheral surface of a small hole as an inspection target hole in the inspection target made of the measured object 1 to the image transmission member 2 A light adjusting member composed of a disk-shaped anti-reflective plate 12 that absorbs the light is extended at the tip of the image transmission member 2 in a direction perpendicular to the inner peripheral surface of the inspection object hole via a rod-like support portion SP. A disk-shaped member that is fixedly disposed relative to the image transmission member 2 and extends in a direction perpendicular to the inner peripheral surface of the hole to be inspected to a part of the light adjustment member formed of the anti-reflection plate 12. Illumination light diffusion composed of an illumination light diffusion plate 12a made of Since the step is arranged, the light adjustment member is fixedly arranged relative to the image transmission member, and the illumination light diffusing means is arranged on a part of the light adjustment member, so that the imaging position can be obtained with a simple configuration. As a result, it is possible to obtain a small-diameter hole inner peripheral surface inspection apparatus capable of detecting the defect more accurately by reducing the variation in brightness due to the increase in the amount of light contributing to imaging.

In the embodiment according to the present invention, configurations shown in the following items (1) to (3) are proposed.
(1) An image transmission member that transmits an image of the inner surface of the small-diameter hole to the imaging device, an imaging unit that captures the transmitted image, an illumination unit for illuminating the inner surface of the small-diameter hole, and illumination light from the illumination unit An endoscope composed of a light guide member that transmits to the inner surface, a moving table that moves the endoscope in the depth direction of the small-diameter hole, and a anti-reflective plate that inserts a low-reflection plate near the bottom surface of the small-diameter hole to be measured Plate insertion means, image development means for developing a plurality of images taken by the imaging means into a two-dimensional image of the inner surface of the hole, and defect detection means for detecting defects from the two-dimensional image developed by the image development means Small-diameter hole inner surface inspection device.
(2) A small-diameter hole inner surface inspection apparatus characterized in that instead of the reduced reflection plate inserting means, reduced reflection means is arranged on the front surface of the endoscope.
(3) A small-diameter hole inner surface inspection apparatus, wherein illumination light diffusing means is arranged on a part of the de-reflection means.

  According to the embodiment of the present invention, since the anti-reflective plate is inserted into the oil flow path near the bottom surface of the valve control hole, an image with little brightness fluctuation can be obtained regardless of the imaging position of the endoscope. Obtainable.

It is a block diagram which shows the structure in Embodiment 1 by this invention. It is explanatory drawing which shows the image expansion | deployment operation | movement in Embodiment 1 by this invention. It is a block diagram which shows the structure in Embodiment 2 by this invention. It is explanatory drawing which shows the image expansion | deployment operation | movement in Embodiment 2 by this invention. It is a block diagram which shows the other structure in Embodiment 2 by this invention. It is a block diagram which shows the structure in Embodiment 3 by this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Object to be measured, 2 Image transmission member, 3 Imaging means, 4 Illumination means, 5 Light guide member, 6 Endoscope, 8, 11a, 11b Decrease reflection plate, 12 Decrease reflection plate, 12a Illumination light diffusion plate, 13 Holding Ingredients.

Claims (5)

  A light guide member that transmits illumination light to the inner peripheral surface of the inspection target, an image transmission member that is disposed so as to be movable relative to the inspection target along the inner peripheral surface of the inspection target, and the inspection target Imaging means for imaging the inner peripheral surface of the inspection object by light transmitted from the inner peripheral surface via the image transmission member, and defect detection means for detecting a defect from the image captured by the imaging means. An inspection apparatus comprising: a light adjusting member that absorbs at least part of light other than light directed from the inner peripheral surface of the inspection target toward the image transmission member.   A light guide member that transmits illumination light to the inner peripheral surface of the inspection target, an image transmission member that is disposed so as to be movable relative to the inspection target along the inner peripheral surface of the inspection target, and the inspection target Imaging means for imaging the inner peripheral surface of the inspection object by light transmitted from the inner peripheral surface via the image transmission member, and defect detection means for detecting a defect from the image captured by the imaging means. A light adjustment member that absorbs at least a part of light other than light directed from the inner peripheral surface of the inspection target to the image transmission member, and is fixed relative to the inspection target. apparatus.   A light guide member that transmits illumination light to the inner peripheral surface of the inspection target, an image transmission member that is disposed so as to be movable relative to the inspection target along the inner peripheral surface of the inspection target, and the inspection target Imaging means for imaging the inner peripheral surface of the inspection object by light transmitted from the inner peripheral surface via the image transmission member, and defect detection means for detecting a defect from the image captured by the imaging means. A light adjusting member that covers the bottom surface of the inspection object connected to the inner peripheral surface of the inspection object and absorbs at least a part of light other than light directed from the inner peripheral surface of the inspection object to the image transmission member. Inspection apparatus characterized by being relatively fixedly disposed with respect to.   A light guide member that transmits illumination light to the inner peripheral surface of the inspection target, an image transmission member that is disposed so as to be movable relative to the inspection target along the inner peripheral surface of the inspection target, and the inspection target Imaging means for imaging the inner peripheral surface of the inspection object by light transmitted from the inner peripheral surface via the image transmission member, and defect detection means for detecting a defect from the image captured by the imaging means. An inspection characterized in that a light adjusting member that absorbs at least a part of light other than light directed from the inner peripheral surface of the inspection target to the image transmission member is fixed relative to the image transmission member. apparatus. 5. The inspection apparatus according to claim 4, wherein illumination light diffusing means is disposed on a part of the light adjusting member.

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