JP2507254Y2 - 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 metallic material are observed with a microscope, and the quality of the metallic material is determined by the shape and distribution state thereof.

According to the ASTM method, non-metallic inclusions are classified into A type, B type, C type, D type and B type as shown in Fig. 3 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. Further, 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 video 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.

Then, the density information is sent to the host CPU 11 via the control CPU 10, and the image-processed image of the sample 1 is displayed on the image monitor 12.

Further, FIG. 5 shows the state of the holder 2 in this inspection apparatus.

In FIG. 5, the holder comprises an upper lid 20a and a lower box 20b, and rectangular observation windows 21 are formed at four locations on the upper lid 20a.

The lower box 20b is divided into four storage portions corresponding to the observation window 21, and the inspection sample 30 is stored in each of them.

The test sample 30 is made into one test sample 30 by integrally fixing the sample piece 32 to the resin 31.

The inspection sample 30 is stored in the storage portion of the lower box 20b, and the sample piece 32 is observed through the observation window 21 when covered with the upper lid 20a.

In the inspection by the inspection device for non-metallic inclusions using such image processing technology, it is important to accurately grasp the shape and distribution state of the non-metallic inclusions contained in the sample.

However, in the above-mentioned inspection apparatus, when the ITV camera is attached to the microscope, one side of the ITV camera screen and one side of the sample, that is, the holder are not in a parallel state, and the orientation direction of one side of the screen and the sample window is deviated. It may be installed at an incorrect angle.

Such inconvenience of the mounting angle becomes particularly remarkable when the ITV camera is mounted by screwing because the mounting angle is adjusted depending on the screwing condition.

When the sample and the ITV camera are not aligned in the axial direction, the density of each pixel forming one screen is converted into digital density information to form an image. There is a big problem that an image is formed as a shape different from the shape of the metal inclusion.

In particular, in the ASTM method, the type of non-metallic inclusions is classified according to the shape and direction of the non-metallic inclusions, and the quality of the metallic material is determined. In a worse case, a situation may occur in which non-metallic inclusions cannot be captured.

Therefore, it is important to mount the ITV camera at an appropriate angle with respect to the sample.

(Problems to be Solved by the Invention) As described above, in the conventional inspection apparatus for non-metallic inclusions, there is a problem that a serious error occurs in the inspection result due to the deviation of the arrangement angle between the ITV camera and the sample. , ITV
It is desired to correctly confirm the mounting angle of the camera and obtain accurate inspection results.

The present invention has been made in order to solve such a problem, and appropriately sets the arrangement angle between the ITV camera and the sample,
An object of the present invention is to provide an inspection device for non-metallic inclusions that can perform accurate inspection.

[Construction of the Invention] (Means for Solving the Problem) The inspection device for non-metallic inclusions of the present invention magnifies a sample including non-metallic inclusions on a stage with a microscope, and an image of the magnified sample is shown. In a non-metallic inclusion inspection apparatus for converting the non-metallic inclusions into an image signal by an imaging means, displaying the image of the sample on the display means, and analyzing the non-metallic inclusions.
A holder that can accommodate a plurality of the samples, has a rectangular observation window for each accommodation portion, and is placed on the stage, and the imaging unit and the observation unit on the screen of the display unit. And a line signal generating means for generating a reference line signal for matching with one side of the window.

(Operation) The inspection device for non-metallic inclusions of the present invention is for aligning the image pickup means such as a camera and one side of the holder containing the sample on the screen of the display means such as an image monitor for displaying the image of the sample. Since the line signal generating means for generating the reference line signal is provided, it is possible to adjust the mounting angle of the camera so as to match the edge of the sample with the displayed reference line while monitoring the image.

Therefore, the imaging means can be attached at an appropriate and correct angle with respect to the arrangement direction of the inspection sample, and accurate inspection can be performed.

(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.

In addition, an image monitor that displays the image processed image
A portion related to 340 will be described with reference to FIGS. 2 (a) and (b).

In these figures, 341 is the screen of the image monitor 340, and the reference line 342 is displayed on the screen 341 by the line signal generating means and the image 343 of the sample 100 is displayed.

FIG. 2A shows that the edge 343e of the image 343 of the sample (that is, the boundary line between the sample and the observation window of the holder) and the reference line 342 are deviated from each other in the axial direction, and the camera has a correct angle with respect to the sample. It is not installed in.

While inspecting the screen 341, the inspector rotates the camera until the reference line 342 and the edge 343e of the image 343 of the sample are parallel to each other so that the line directions on the screen coincide with each other as shown in FIG. 2B.

In this way, by displaying the reference line on the image monitor, the angle of the camera with respect to the sample can be accurately adjusted, the shape of the non-metallic inclusion can be correctly captured, and an accurate inspection result can be obtained.

In this embodiment, the example in which the reference line is displayed on the image monitor 340 that displays the image after the image processing is described, but the reference line may be displayed on the image monitor 330 that displays the raw image. Of course.

[Advantages of the Invention] As described above, in the present invention, the line signal generating means for generating the reference line signal for aligning the imaging means and one side of the observation window of the holder accommodating the sample on the screen of the display means. Therefore, by aligning the reference line with one side of the observation window, it is possible to match the plane axial directions of the image pickup means and the sample and attach the image pickup means at an appropriate angle.

Therefore, the nonmetallic inclusions contained in the sample can be accurately analyzed, and highly reliable inspection results can be obtained.

[Brief description of drawings]

FIG. 1 is a block diagram showing the construction of a non-metallic inclusion inspection apparatus according to an embodiment of the present invention, FIG. 2 is a diagram showing the image monitor shown in FIG. 1, and FIG. 3 is a non-metallic inclusion. FIG. 4 is a diagram showing classification, FIG. 4 is a diagram for explaining a conventional inspection device, and FIG.
The figure is a diagram showing a holder. 100 ... Sample, 200 ... Optical system, 210 ... Holder, 220 ... Microscope, 260 ... Stage, 300 ... Processing system, 310 ... Information processing device, 320 ... Image processing device, 330, 340 ... Image monitor, 341 ...
Screen, 342 ... reference line, 343 ... sample image, 350 ... video printer, 360 ... printing printer.

Claims (1)

(57) [Scope of utility model registration request] 1. A sample containing non-metallic inclusions is magnified on a stage by a microscope, an image of the magnified sample is converted into a video signal by an image pickup means, and the image of the sample is displayed by a display means. In the non-metal inclusion inspection device for analyzing the non-metal inclusions, a plurality of the samples can be accommodated, each accommodating portion has a rectangular observation window, and the non-metallic inclusions are mounted on the stage. And a line signal generating means for generating a reference line signal for aligning the imaging means and one side of the observation window on the screen of the display means. Inspection equipment.