JPH084615Y2 - Inspection device for non-metallic inclusions - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Field of Industrial Application) The present invention relates to an inspection device for non-metallic inclusions using image processing technology.

(Prior Art) Since non-metallic inclusions existing in a metal material influence various mechanical properties of the metal material, quantitative analysis of these is very important for quality control of the metal material.

Conventionally, ASTM (American Society for Testing Mat) has been used as a method for inspecting non-metallic inclusions existing in metallic materials.
erials) method is known. In this method, non-metallic inclusions appearing on the surface of a sample taken from a metal material are observed with a microscope, and the quality of the metal material is determined by the shape and distribution state thereof.

According to the ASTM method, the non-metallic inclusions are A type, B type, C type, D type, and B type as shown in Fig. 6 depending on the shape and distribution state.
TiB system and TiD system which are distinguished by the image shades of D-type and D-type
It is classified into 6 types. Furthermore, each of these 6 types is classified into Thin (thin type) and Heavy (thick type). Then, the quality of the metallic material is determined for each of the classified non-metallic inclusions.

By the way, in visual inspection by the inspector's naked eyes, there are problems in terms of inspection speed and error. Therefore, recently, an inspection apparatus for automatically inspecting a metal material using an image processing technique has been developed.

 The configuration of this inspection device will be described with reference to FIG.

A sample 1 taken from a metal material is stored in a holder 2 and then fixed to a stage 4 of a microscope 3. The sample 1 fixed on the stage 4 is illuminated by the illumination light source 5 coaxially with the optical axis of the microscope 3.

The image of the sample 1 magnified by the microscope 3 is
It is converted into a video signal by an ITV camera (Industrial Television) 6 attached to the.
The image signal output from the ITV camera 6 is input to the image processing device 7 and subjected to predetermined image processing.

The image processing device 7 is composed of an A / D converter 8, a frame memory 9, and a control CPU 10. The input video signal is first of all the pixels constituting one screen by the A / D converter 8. The density is converted into, for example, 8-bit digital density information and sequentially stored in the frame memory 9.

Here, an enlarged view of the sample 1 and the holder 2 on the stage 4 is shown in FIG.

In FIG. 5 (a), the sample 11 cut into a sample piece having a predetermined shape is integrated with the black resin 12 to form one cylindrical test piece 13.

The inspection piece 13 is stored in a holder 14 of 4 storage types,
This holder 14 has a stage as shown in FIG. 5 (b).
Placed on 15.

The position of the surface of the stage 15 is defined by XY coordinates, and by designating the position to be inspected by XY coordinates,
The stage moves so that the designated stage position is below the microscope.

That is, after the holder 14 is placed on the stage 15,
The stage 15 moves so that the microscope scans along the XY coordinate axes, and all the test pieces are observed from one end to the other end of the sample 11 stored in the holder 14 and placed on the stage 15. It

In the inspection by the inspection device for non-metallic inclusions using such image processing technology, it is important to observe the sample securely and thoroughly.

However, when the holder is placed on the stage, the inspector places it each time, so it is not possible to decide where on the stage it should be placed, and it is placed properly at the pre-entered inspection start position. There is a case where the holder is not provided or the holder is placed in a state where the holder is bent with a deviation from the defined XY coordinate axes.

Then, since the field of view of the microscope is very small with respect to the sample, it takes an unnecessary time to confirm the position of the holder, which causes a problem that the inspection cannot be performed quickly.

Furthermore, since the scanning direction of the microscope and the orientation of the sample do not match, there arises a problem that the sample does not enter the field of view of the microscope accurately, resulting in a situation that a correct inspection result cannot be obtained.

Therefore, it is important to confirm the position of whether the holder is correctly placed at the specified position on the stage.

(Problems to be Solved by the Invention) As described above, in the conventional inspection device for non-metallic inclusions, it is difficult to confirm whether the holder is properly placed at the predetermined position on the prescribed stage, There is a problem that it takes an unnecessary time before starting the inspection, and it is desired to promptly confirm the position of the holder on the stage.

The present invention has been made to solve such a problem, and improves the positional accuracy of the stage and the holder that stores the sample placed on the stage, and is a non-metallic material that enables quick position confirmation. An object is to provide an inspection device for inclusions.

[Structure of the Invention] (Means for Solving the Problem) The inspection device for non-metallic inclusions of the present invention stores a sample containing non-metallic inclusions in a holder, and mounts the holder on a stage defined by coordinate axes. In a non-metallic inclusion inspection device that places and magnifies with a microscope to analyze the non-metallic inclusions, the holder has a mark for position confirmation formed at a predetermined portion of the holder, and the stage is pre-entered. When the mark is moved to the coordinate position of the marked mark, it is characterized by including mark detecting means for detecting whether the mark enters the visual field of the microscope at a predetermined area ratio.

(Operation) In the present invention, a mark for position confirmation is formed at a predetermined portion of the holder containing the inspection sample, and the mark detection means for detecting this mark is provided. It is possible to quickly confirm the position of the holder by checking whether or not a mark is included in the field of view of the microscope when the holder is moved to the coordinate position of.

 Therefore, the inspection can be performed quickly.

(Example) Next, the Example of this invention is described using drawing.

FIG. 1 is a view showing the arrangement of a nonmetallic inclusion inspection apparatus according to an embodiment of the present invention.

As shown in the figure, this inspection apparatus is an optical system 200 for obtaining a video signal in which a sample 100 taken from a metal material is magnified, and a video signal obtained by the optical system 200 is image-processed to perform non-processing. The processing system 300 analyzes metal inclusions.

Further, the optical system 200 is a holder 210 for accommodating a plurality of samples 100, an optical microscope 220 for optically magnifying the sample surface, and an ITV camera for imaging the sample surface magnified by the optical microscope 220 and converting it into a video signal. (Industrial Television) 230, an illumination light source 240 that illuminates the sample surface coaxially with the optical axis of the microscope 220, an autofocus controller 250 that controls the autofocus mechanism included in the microscope 220, and the position of the holder 210 X-Y stage 260, which moves the X-Y2 direction, and X-axis based on an instruction from the processing system 300.
An XY stage controller 270 that controls the movement of the -Y stage 260.

Further, the processing system 300 inputs the video signal from the ITV camera 230 based on an instruction from the information processing device 310 that controls the entire inspection device and processes the measurement data, and performs image processing necessary for the inspection. Image processing device 320, ITV camera 230
The image monitor 330 that displays the raw image captured by the image monitor, the image monitor 340 that displays the image processed by the image processing device 320, and the video printer that outputs the hard copy of the image processed by the image processing device 320. Reference numeral 350 denotes a printer 360 that prints measurement data processed by the information processing apparatus 310.

Further, FIG. 2 shows a detailed configuration of a portion related to the holder 210.

In the figure, a holder 210 is composed of an upper lid 211 and a lower box 212, and sample windows 213 are formed at four locations on the upper lid 211 to accommodate four sample pieces.

Each sample piece is fixed to the black resin and housed in the holder 210 like the inspection piece described above with reference to FIG.

Then, the sample portion of the test piece in which the sample and the black resin are integrated is arranged so as to be seen through the sample window 213 of the holder 210, and the diameter is provided in the vicinity of the corner of the sample window 213, that is, the portion corresponding to the black resin. A 1 mm mark hole 214 is formed.

Thereby, due to the silver color of the holder 210 made of stainless steel and the black color of the resin that appears inside the mark hole 214,
There is a clear contrast of light and dark.

Therefore, when observing the mark hole 214 of the holder 210 with a microscope having an image field of view of, for example, 0.88 mm × 0.6 mm,
The presence of the 1 mm diameter mark hole 214 is immediately confirmed.

Next, using the holder 210 of this embodiment, a stage 260
The operation for confirming the above position will be described with reference to the flowchart shown in FIG.

First, the microscope 220 is set at the origin position of the XY stage 260 (step 201).

Then, the microscope 220 is set so that the microscope 220 is set at the position of the mark hole 214 which is defined by the XY coordinates and is registered in advance.
-Move the Y stage 260 (step 202).

The image at the moved position constitutes a video signal for one screen input to the A / D converter 322.
It is converted into digital density information of each of the 12 pixels and sequentially stored in the frame memory 323 and taken in (step 203).

Then, the density information stored in the frame memory 323 is binarized depending on the brightness (step 204).

Based on the binarized information, the ratio of the bright portion or the dark portion in all the pixels is totaled (step 205).

Here, the bright part is a holder part made of stainless steel, and the dark part is a mark hole part colored with resin.

Then, it is determined from the result of the above aggregation whether or not the dark part, which means the mark hole, occupies an area of 50% or more in all pixels (step 206).

If it is determined that the dark portion occupies an area of 50% or more in all the pixels, it is confirmed that the holder is properly placed on the stage, and a position confirmation display is displayed (step 207).

On the other hand, when it is determined in step 206 that the area ratio of the dark area in all the pixels is less than 50%,
The holder placement position on the stage is not appropriate, and a position correction display is displayed (stage 208).

After properly mounting the holder on the stage according to such a display for confirming the position, the stage can be moved to a desired inspection start position by a predetermined command.

In this way, by forming the mark hole, the position of the holder can be confirmed by an easy method using the contrast of light and darkness of the image field, and the inspector can place the holder at the correct position in a shorter time. Therefore, the inspection can be speeded up.

In addition, although an example in which one mark hole is formed has been described in this embodiment, if two or more mark holes are formed along one side of the holder, the stage is moved in the axial direction to judge the mark hole inspection. It is possible to confirm the parallel state of the holder by repeating the number of the mark holes formed with.

Further, not only holes may be formed as marks, but also colored marks may be formed on the holder to effectively form the marks according to the size of the image field of the microscope.

[Advantages of the Invention] As described above, in the present invention, a mark for position confirmation is formed at a predetermined portion of a holder that stores an inspection sample,
The coordinate position of the mark is input in advance, and when the stage is moved to the coordinate position of the input mark, the mark detecting means detects whether or not the mark is included in the field of view of the microscope.

Therefore, the position of the holder can be easily confirmed, and the inspection can be speeded up.

[Brief description of drawings]

FIG. 1 is a block diagram showing the structure of an inspection apparatus for non-metallic inclusions according to one embodiment of the present invention, FIG. 2 is a view showing a holder in the inspection apparatus shown in FIG. 1, and FIG. 3 is FIG. FIG. 4 is a flow chart showing the position confirmation processing operation in the inspection apparatus shown in FIG. 4, FIG. 4 is a view for explaining the conventional inspection apparatus, and FIG. 5 is an enlarged view showing the state of the sample and the holder on the stage. FIG. 6 is a diagram showing the classification of non-metallic inclusions. 100 ... Sample, 200 ... Optical system, 210 ... Holder, 211 ... Top lid,
212 ... Lower box, 213 ... Specimen window, 214 ... Mark hole, 220 ... Microscope,
260 ... Stage, 300 ... Processing system, 310 ... Information processing device, 320
Image processor, 330, 340 ... Image monitor, 350 ... Video printer, 360 ... Printing printer.

Claims (1)

[Scope of utility model registration request] 1. A non-metallic interposition for analyzing a non-metallic inclusion by accommodating a sample containing a non-metallic inclusion in a holder, placing the holder on a stage defined by coordinate axes, and enlarging it with a microscope. In the object inspection apparatus, the holder is formed with a mark for position confirmation at a predetermined portion of the holder, and when the stage is moved to the coordinate position of the mark input in advance, the mark is predetermined in the visual field of the microscope. An inspection apparatus for non-metallic inclusions, characterized by comprising mark detection means for detecting whether or not the area has entered.