JPH11352076A - Apparatus and method for inspecting defect of molded product - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide the subject apparatus and method facilitating the inspection of the flaw molded product, comprising an annular body having a surface to be inspected on its outer periphery, capable of suppressing inspection mistakes and facilitating the control and analysis of data, such as the state or number of flaws of a defective product. SOLUTION: The state of a sealing surface 51a of a seal ring 51 is photographed, and the flaw of the sealing surface of the seal ring 51 is inspected on the basis of the image of the photographed surface to be inspected, and the image of the contour shape of the outer peripheral surface of the rotating seal ring 51 is taken to inspect the photographed contour shape of the outer peripheral surface of the seal ring 51.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus and a method for inspecting a defect of an annular body for inspecting a defect on a surface to be inspected on an outer periphery of a molded article made of an annular body such as a seal ring.

[0002]

2. Description of the Related Art For example, in the case of a molded article of an annular body such as a seal ring, it is necessary to inspect the seal surface for defects such as scratches and deformation after molding in order to secure the sealing function of the seal ring. Molded products such as seal rings
For example, it is produced by molding a molding material such as rubber by a molding machine. In this molding step, the mold used for molding the seal ring is usually a split mold, and burrs are generated between the divided surfaces of the mold. Although burrs are formed on the inner and outer circumferences of the annular seal ring, burrs on the outer circumference are originally small and can be ignored. However, burrs may be generated enough to cause defects in molded products. In addition, defects such as dents may occur on the sealing surface due to deposits on the mold or insufficient filling of the molding material. For this reason, in the case of a molded article of an annular body such as a seal ring, it is necessary to inspect for burrs in addition to inspecting for defects on the sealing surface.

[0003]

In the prior art, the above-mentioned inspection of the seal surface and the burr defect on the outer periphery of the seal ring has been performed visually by an operator using a magnifying glass, for example. For this reason, especially in the case of a small seal ring, it is difficult to visually and simultaneously determine the state of the seal surface and the burr, it takes time, and it is easy for defects to be overlooked. In addition, the defect inspection is a manual operation, and the inspection of the sealing surface and burrs is performed at the same time. However, there was a disadvantage that analysis took time.

The present invention facilitates defect inspection of a molded article made of an annular body having a surface to be inspected on the outer periphery, suppresses inspection errors, and facilitates management and analysis of information such as the state and number of defects of the defective article. It is an object of the present invention to provide a defect inspection apparatus and a defect inspection method for a molded article.

[0005]

SUMMARY OF THE INVENTION The present invention relates to a defect inspection apparatus for a molded article formed of an annular body having a surface to be inspected on the outer periphery, the rotation inspection means holding the molded article and being rotatable.
First imaging means for imaging the state of the surface to be inspected of the molded product located at the first imaging position, and imaging of the contour shape of the inspected surface of the molded product rotating at the second imaging position Second imaging means for moving the molded article with respect to the first imaging position and the second imaging position;
The molded product is moved between the first and second imaging positions, a control command for rotating the molded product is output to the moving unit and the driving unit, and the first and second imaging units perform imaging. Subject the processed image signal to predetermined processing,
Defect inspecting means for comprehensively judging a defect of the molded article from a state and a contour shape of the inspection surface.

In the present invention, the state of the surface to be inspected of the molded product is imaged by the first imaging means for the molded product arranged at the first imaging position. The held molded product is moved to the second imaging position by the moving unit, and is imaged by the second imaging unit while being rotated by the rotation driving unit. As a result, the contour shape of the surface to be inspected of the molded product is imaged by the second imaging means, and a predetermined process is performed on the imaged signal by the image processing means. The captured image is
A predetermined process is performed by the image processing means, and a defect on the inspection surface of the molded product is comprehensively determined based on the processed image.

The present invention relates to a method for inspecting a defect of a molded article formed of an annular body having a surface to be inspected on an outer periphery, wherein a step of imaging a state of the inspected surface of the molded article, Imaging the contour of the rotating inspected surface while rotating; and comprehensively judging a defect of the molded article from the imaged state and contour of the inspected surface.

[0008]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is an explanatory diagram showing one configuration example of a molded product defect inspection system according to one embodiment of the present invention. In FIG. 1, a defect inspection system 1 includes a holding shaft 3, a holding shaft driving motor 5, and a first imaging device 7.
, Lighting device 9, diffusion plate 11, cylinder device 13
, The second imaging device 15, the illumination device 17, and the diffusion plate 1
9, a discharge box 21, a personal computer 31,
And a display device 32.

The holding shaft 3 is for holding a molded product by fitting it into an insertion hole of a molded product to be inspected, which will be described later. The holding shaft 3 is connected to a holding shaft driving motor 5 and is rotatable by the driving of the holding shaft driving motor 5.

The holding shaft driving motor 5 is a motor which can be positioned at an arbitrary rotation angle and can rotate continuously, and for example, a servo motor can be used.

The cylinder device 13 holds the holding shaft 3 and the holding shaft driving motor 5, and moves the holding shaft 3 and the holding shaft driving motor 5 between the first imaging position A and the second imaging position B. It can be moved linearly between them. The cylinder device 13 has, for example, a cylinder driven by air pressure or hydraulic pressure, and the cylinder can be moved to an arbitrary position. .

The holding shaft driving motor 5 and the cylinder device 13 are, as shown in FIG.
1 is controlled. Personal computer 31
Has a rotation control unit 31a and a cylinder control unit 31b inside.
And a defect inspection unit 31c and a tally management unit 31d. The rotation control unit 31a outputs a control command 5s to the holding shaft driving motor 5, and controls the rotation position and the rotation speed of the holding shaft driving motor 5. Specifically, the first
In the imaging position A, the rotation of the holding shaft driving motor 5 is intermittently controlled, and in the second imaging position B, continuous rotation control is performed at a predetermined rotation speed. The cylinder control unit 31b outputs a control command 13s to the cylinder device 13 and performs position control of the cylinder device 13. The defect inspection unit 31c
And the image pickup signals from the second image pickup devices 7 and 15 are fetched and subjected to predetermined processing to comprehensively judge the defects of the molded article from the state of the surface to be inspected and the contour shape. Outputs information such as a processed image. Further, the counting management unit 31d plays a role of counting and managing the information of the defect inspection result.

The first imaging device 7 has a field of view facing the outer periphery of the holding shaft 3 located at the first imaging position A.
The state of the surface to be inspected on the outer periphery of the molded product can be imaged from the radial direction of the molded product held in the apparatus. First imaging device 7
For example, a CCD camera using a CCD (charge coupled device) is used. The imaging signal of the first imaging device 7 is taken into the personal computer 31.

The illuminating device 9 illuminates a surface to be inspected of a molded product held by the holding shaft 3 located at the first imaging position A with light. The illumination device 9 includes a plurality of light sources, and various light sources such as a halogen lamp, a xenon lamp, and a fluorescent lamp can be used as the light source. The light from the illumination device 9 is arranged in a direction substantially perpendicular to the arrangement direction of the first imaging device 7 so as not to directly enter the field of view of the first imaging device 7.

When transmitting the light from the lighting device 9, the diffusion plate 11 serves to diffuse the light and equalize the amount of light incident on the molded product held by the holding shaft 3. The two diffusion plates 11 are provided between the first imaging position A and the lighting device 9. As the diffusion plate 11, for example, a frosted glass plate, a milky white glass plate, or a transparent resin plate such as acryl formed with irregularities and grooves is used.

The second imaging device 15 has a second imaging position B
In order to image the contour of the surface to be inspected on the outer periphery of the molded product held by the holding shaft 3 moved to the second position, the field of view of the second imaging device 15 is changed to the holding shaft 3 moved to the second imaging position B. Facing the surface to be inspected from the outer peripheral side of the molded product held at the position. Second
As the imaging device 15, the same configuration as that of the above-described first imaging device 7 can be used. The imaging signal of the second imaging device 15 is taken into the personal computer 31. In the present embodiment, the contour of the surface to be inspected of the molded product is imaged by rotating the holding shaft 3 moved to the second imaging position B at a predetermined speed.

The illuminating device 17 is provided from behind the molded product held by the holding shaft 3 moved to the second imaging position B from behind.
Light is radiated through 9. The illumination device 17 may have the same configuration as the illumination device 9 described above. The diffusion plate 19 diffuses the light emitted from the illumination device 17 when transmitting the light, and makes the amount of light incident on the field of view of the second imaging device 15 uniform. The diffusion plate 19 may have the same configuration as the diffusion plate 11 described above.

The discharge box 21 is for discharging a molded product having undergone the defect inspection at the second image pickup position B into a good product and a defective product.

FIG. 3 is a sectional view showing a seal ring as an example of a molded product to be inspected by the defect inspection system. The seal ring 51 shown in FIG. 3 is an X-shaped ring having an X-shaped cross section. The seal ring 51 has two seal surfaces 51a on the outer periphery, and has an insertion hole 51b into which a shaft is inserted on the inner periphery.
In addition, a recess is formed between the seal surfaces 51a. The holding shaft 3 is fitted and inserted into the insertion hole 51b of the seal ring 51. The seal ring 51 cannot exhibit sufficient sealing performance when defects such as scratches, deformation, and attachment of foreign matter are present on the outer peripheral sealing surface 51a. For this reason, it is necessary to inspect whether or not the above-described problem exists on the sealing surface 51a of the seal ring 51.

Since the mold used for molding the seal ring 51 is usually a split mold, burrs are generated between the divided surfaces of the mold. For example, the seal ring 5 shown in FIG.
The dividing surface of the dividing type is located at the position indicated by the arrow C of FIG. 1, and protruding outer peripheral burrs are easily generated at this position. Generally, the outer peripheral burrs are originally small and negligible. However, there are cases where the outer peripheral burrs become large enough to cause defects in the molded product. For this reason, it is necessary to inspect not only the state of the sealing surface 51a but also whether or not the outer peripheral burr exists on the seal ring 51.

Next, an example of inspection of the sealing surface 51a of the seal ring 51 and the outer peripheral burrs using the defect inspection system having the above configuration will be described with reference to a flowchart shown in FIG. First, the seal ring 51 is mounted on the holding shaft 3 (Step S1). The attachment of the seal ring 51 to the holding shaft 3 is automatically performed using a parts feeder or the like, but may be performed by an operator himself.

Next, the seal ring 51 held on the holding shaft 3 is moved to the first imaging position A (step S).
2). The movement of the seal ring 51 to the first imaging position A is performed by outputting a control command previously stored in the personal computer 31 to the cylinder device 13.

Next, an image of the seal surface 51a of the seal ring 51 is taken by the first image pickup device 7 (step S3). Since the field of view of the first imaging device 7 is directed from the outer periphery of the seal ring 51 to the seal surface 51a,
The area imaged by the first imaging device 7 is a part of the seal surface 51a. The seal surface 51a of the seal ring 51 imaged by the first imaging device 7 is taken into the personal computer 31 and subjected to predetermined image processing (step S4). In the image processing in the personal computer 31, for example, the amount of light received by each pixel of the first imaging device 7 is binarized by a predetermined threshold value. The image subjected to this processing is output to the display device 32, and the inspection of the sealing surface is performed based on this image (step S5). In the present embodiment, the personal computer 31 performs a binarization process on the image captured by the first imaging device 7. However, the image captured by the first imaging device 7 is converted into a predetermined gradation. The state of the seal surface 51a of the seal ring 51 may be inspected based on this.

The image displayed on the display device 32 is, for example, as shown in FIG. As shown in FIG. 5, the sealing surface 51 a
And the burr formation region C are black, and the other regions are white. For example, if there is a flaw, deformation, or attachment of a foreign substance on the sealing surface 51a, the reflection of light changes in that area, and the amount of light incident on the first imaging device 7 decreases, so that the black area P shown in FIG. Appears as a perfect image. From the number, area, etc. of the black regions P, it can be determined that there is a flaw, deformation, or attachment of foreign matter on the sealing surface 51a.

Here, the sealing surface 51 of the seal ring 51
It is confirmed whether imaging of the entire circumference of a has been completed (step S
7). If imaging and inspection of the entire circumference of the seal surface 51a of the seal ring 51 have not been completed, the holding shaft 3 is rotated at a predetermined angle (step S6). As a result, an area of the seal surface 51a of the seal ring 51, which has not been imaged yet, is imaged, and the inspection of the entire circumference of the seal surface 51a of the seal ring 51 is reliably performed.

When imaging and inspection of the entire circumference of the seal surface 51a of the seal ring 51 are completed, the seal ring 51 held on the holding shaft 3 is moved to the second imaging position B (step S8).

From the image obtained by the first image pickup device 7, it is difficult to confirm the presence and size of the outer peripheral burr formed in the burr forming area C on the outer periphery of the seal ring 51. For this reason, the presence and size of the outer peripheral burr are inspected at the second imaging position B. First, the holding shaft 3 is continuously rotated at a predetermined speed so that the seal ring 1 is rotated (step S9), and the outer peripheral shape is imaged by the second imaging device (step S10).

In this state, the contour of the outer peripheral surface of the rotating seal ring 51 disposed at the second imaging position B is imaged by the second imaging device 15. Lighting device 17
Irradiates light from behind the seal ring 51 toward the second imaging device 15, so that light from the illumination device 17 is partially blocked by the seal ring 51. The image captured by the second imaging device 15 is a seal ring 5
1 and the contour shape of the outer peripheral surface of the seal ring 51 can be imaged.

An image signal picked up by the second image pickup device 15 is taken into the personal computer 31 and
Predetermined image processing is performed (step S11). In the personal computer 31, for example, the amount of light received by each pixel of the second imaging device 15 is binarized by a predetermined threshold value, and is output to the display device 32. Display device 3
The image output to 2 is, for example, as shown in FIG. 6, and the contour shape of the outer peripheral surface of the seal ring 51 can be recognized from the region indicated by the black region in FIG. 6. The outer peripheral burr of the seal ring 51 is inspected based on the contour of the outer peripheral surface of the seal ring 51 (step S12).
When there is an outer peripheral burr, an image B of the outer peripheral burr is displayed on the burr forming area C of the seal ring 51. In the present embodiment, for example, even when the outer peripheral burr exists not in the entire periphery of the seal ring 51 but in a part thereof,
Since the seal ring 51 is continuously rotated, the image B of the outer peripheral burr is displayed. Image B of outer peripheral burr shown in FIG.
The presence of the outer peripheral burr formed in the burr forming region C of the seal ring 51 is determined from the size of. For example, when the size of the burr in the burr formation region C is equal to or larger than the reference value, it can be determined that the burr formation region C has a defect.

Next, a defect of the seal ring 51 is comprehensively determined from the inspection results of both the seal surface 51a, which is the inspection surface of the seal ring 51, and the burr forming region C (step 13). For example, when there is a defect in both the seal surface 51a and the burr formation region C, the seal ring 51 is determined to be defective, or when there is a defect in at least one of the seal surface 51a and the burr formation region C, ,
The seal ring 51 is determined to be defective.

After performing the defect inspection of the seal ring 51, the defect inspection information is recorded and updated in the personal computer 31 (step S14). The inspection information of the personal computer 31 includes, for example, the type of the seal ring 51 having the defect, the seal surface 5 of the seal ring 51, and the like.
Various information such as information on whether a defect exists on the surface 1a or the burr forming surface C and the state of the defect can be defined. Even with a non-defective seal ring 51 that is not determined to be defective, the size of the burr in the burr formation region C can be managed.

As described above, according to the present embodiment, the seal surface 5 on the outer periphery of the seal ring 51 which is a molded product of an annular body is provided.
Since the defect inspection of the outer peripheral burr 1a and the outer peripheral burr can be performed separately, the state of the seal surface 51a and the state of the outer peripheral burr can be surely inspected. Further, according to the defect inspection system according to the present embodiment, since the image of the seal ring 51 can be taken into the personal computer 31 and the inspection result can be comprehensively managed in the personal computer 31, the defect inspection information is used as the manufacturing information. It can be used effectively and quickly. Further, in a state where the seal ring 51 is held on the holding shaft 3, an image of an outer peripheral surface of the seal ring 51, which is a surface to be inspected, can be captured and enlarged and displayed on the display device 32. Inspection results can be easily confirmed, and even if a defect such as an inspection error occurs, it can be found early.

In this embodiment, the inspection target is
Although the seal ring 51 called an X-ring is shown, the present invention is not limited to this, and various annular moldings such as a D-ring having a D-shaped cross section and an O-ring having an O-shaped cross section are shown. Applicable to goods.

[0034]

According to the present invention, it is possible to easily perform a defect inspection of the state of the inspection surface and the contour shape of the inspection surface of a molded article made of an annular body having a surface to be inspected on the outer periphery by a series of inspection steps. . Further, according to the present invention, it is not necessary to directly inspect the surface to be inspected of the molded product by visual observation. As a result, inspection labor can be reduced and inspection errors can be suppressed.
Furthermore, according to the present invention, management and analysis of information such as the state and number of defects of defective products can be performed quickly and easily.

[Brief description of the drawings]

FIG. 1 is a perspective view showing one configuration example of a defect inspection system for a molded product according to an embodiment of the present invention.

FIG. 2 is a control block diagram of a holding shaft driving motor and a cylinder device in the defect inspection system according to one embodiment of the present invention.

FIG. 3 is a cross-sectional view showing a seal ring as an example of an inspection target by the defect inspection system according to the embodiment of the present invention.

FIG. 4 is a flowchart illustrating an example of an operation of the defect inspection system according to the embodiment of the present invention.

FIG. 5 is a diagram illustrating an example of an image obtained by performing predetermined processing on an image signal from a first imaging device.

FIG. 6 is a diagram illustrating an example of an image obtained by performing predetermined processing on an image signal from a second imaging device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Defect inspection system 3 ... Holding shaft 5 ... Holding shaft drive motor 7 ... 1st imaging device 9 ... Illumination device 11 ... Diffusion plate 13 ... Cylinder device 15 ... 2nd imaging device 17 ... Illumination device 19 ... Diffusion plate 21: discharge box 31: personal computer 32: display device 51: seal ring

Claims (3)

[Claims] 1. A defect inspection apparatus for a molded article comprising an annular body having a surface to be inspected on an outer periphery, comprising: a rotating holding means for holding the molded article and being rotatable; First imaging means for imaging the state of the inspected surface of the molded article; second imaging means for imaging the contour shape of the inspected surface of the rotating molded article located at the second imaging position; Moving means for moving the molded product with respect to a first imaging position and a second imaging position; and moving the molded product between the first and second imaging positions and rotating the molded product Outputting a control command to the moving unit and the driving unit, performing a predetermined process on an image signal imaged by the first and second imaging units,
A defect inspecting device for inspecting the molded article from a state and a contour shape of the surface to be inspected, the defect inspecting means for comprehensively judging a defect of the molded article. 2. The defect inspection of a molded article according to claim 1, wherein said defect inspection means totalizes and manages information on a defect inspection result of a surface to be inspected of the molded article based on image information subjected to a predetermined process. apparatus. 3. A method for inspecting a defect of a molded article comprising an annular body having a surface to be inspected on an outer periphery, the method comprising: imaging a state of a surface to be inspected of the molded article; and continuously rotating the molded article. Imaging a contour shape of the rotating inspected surface; and comprehensively determining a defect of the molded product from the imaged state and contour shape of the inspected surface. Inspection methods.