JPS6213617B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention particularly relates to a chipping detection device for a throw-away chip.

Chips on the cutting edge of a throw-away chip are a problem as a cutting tool, and defective products with chips have conventionally been detected by visual inspection.

As an alternative to this visual chip detection, automatic detection technology has been provided, but in order to apply it to throw-away chips with various shapes, it is difficult to apply it to throw-away chips with various shapes. In either case, it is necessary to ensure high detection accuracy.

SUMMARY OF THE INVENTION An object of the present invention is to provide a device which has an extremely simple configuration and can accurately detect the presence or absence of chipping not only in throw-away chips but also in the ends of this type of shaped articles.

The present invention will be explained in detail below based on the accompanying drawings. 1 and 2 show the basic principle of an apparatus for detecting chips from the amount of reflected light.

1 is a throw-away chip, and light 2 is projected onto the side of the chip from the horizontal direction. 3 is the lens system,
The reflected light of the projected light 2 is reflected from the throw-away chip 1.
It is arranged so that the image is formed on a narrow strip-shaped photoelectric conversion element 4 provided on the upper side of the . 5 is an amplification circuit for the output of the photoelectric conversion element 4.

By moving the throw-out chip 1 in the direction of arrow A while maintaining the angle between the projected light 2 and the chip side (90 degrees in the case of Fig. 1), all of the ends of the throw-out chip 1 are will be imaged on the photoelectric conversion element 4. Here, if a chip occurs at the end, the reflected light 2a causes diffuse reflection, causing a change in the output of the photoelectric conversion element 4. In this way, chipping at the end of the throw-away chip 1 can be detected.

A general chipping detection device, as shown in Figs. 1 and 2, shines light at right angles to the side surface of the chip 1 (see, for example, Japanese Patent Publication No. 36189/1989).
As a result of various experiments, it has been found that the projection angle between the projector and the throw-away chip 1, which is the object to be inspected, is approximately 50 to 80 degrees, as shown in Fig. 3b, for better chipping signal characteristics. It turned out that there was.

Figure 4 shows the correlation between the missing signal characteristics (S/N ratio) with the S/N ratio on the vertical axis and the projection angle on the horizontal axis. /
The N ratio is 2 or more.

Next, as the photoelectric conversion element 4, a light-receiving element made of silicon single crystal formed into a narrow rectangular shape is used. In the sense that this photoelectric conversion element 4 receives diffused reflection of reflected light, it is common sense that the angle is perpendicular to the side of the throw-away chip 1, but as shown in FIG. In the R portion corresponding to , an unfavorable angle is formed when the thrower tip 1 is moved. Therefore, if the photoelectric conversion element 4 is placed in advance at an angle of 45 degrees with the side, it will be placed at right angles to the R part, making it possible to accurately grasp the reflected light. Furthermore, if the angle is 45 degrees at the side, there will not be much of a problem in receiving light.

Therefore, in this invention, for one throw-a-chip, there are two
The photoelectric conversion elements 4a and 4b are provided to respectively project light 2' and 2'' at different projection angles onto the side surface of the throw-away chip, and to receive the respective reflected lights.

Each of the photoelectric conversion elements 4a and 4b is electrically connected to a signal processing circuit or an amplification circuit 5a and 5b, respectively, and by alternately moving the throw-out chip 1 in the two arrow directions, the presence or absence of chipping can be determined. can be detected quickly and accurately.

As described above, the present invention projects light from two directions at an angle (preferably 50 to 80 degrees) at which a good chipping signal can be obtained from the side surface of the throw-away chip, and Since two photoelectric conversion elements are provided in the form of narrow strips that form an angle of 45 degrees with the wafer, chipping can be detected more accurately and chipping inspection can be performed with high accuracy.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing the basic principle of the device of this invention;
Figures 2a and b are side views and plan views for explaining Figure 1, Figures 3a and b are improved side views and plan views corresponding to Figures 2a and b, and Figure 4 is an illustrative side view and plan view. A comparison diagram of the projection angle and missing signal characteristics (S/N ratio), Figures 5a and b are plan views showing the difference in the arrangement angle of the photoelectric conversion element, and Figure 6 is a schematic configuration of the device of the present invention. FIG. 1... Throw-away chip, 2... Light, 3...
Lens system, 4...Photoelectric conversion element.

Claims (1)

[Claims] 1 The reflected light of light projected from the side onto an object to be inspected, such as a throw-away chip, is received by a narrow strip-shaped photoelectric conversion element placed above the edge of the object to be inspected, and a signal is generated from the output change of this element to the element. In a chip detection device that determines whether or not there is a chip at the edge of an imaged object to be inspected, light is projected onto the side surface of the object to be inspected from two different directions, and the photoelectric sensor is placed at the receiving position of each reflected light for the two light projections. One conversion element is arranged for each, and the two elements are located approximately at a distance from the end side of the object to be inspected.
The chip is arranged at an angle of 45 degrees, and the chip is detected by the two photoelectric conversion elements by horizontally moving the object to be inspected while maintaining a predetermined light projection direction angle. Detection device.