JPS6213618B2 - - 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-out tip 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 chipping detection, automatic detection techniques have been proposed, but there are several problems in applying them to throw-away chips having various shapes.

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 described in detail below based on the accompanying drawings showing examples.

1 is a throw-away chip, and light 2 is projected from the horizontal direction onto the center of the side surface of the chip. Reference numeral 3 denotes a lens system, which is arranged so that the reflected light of the projected light 2 is imaged on a narrow rectangular photoelectric conversion element 4 provided on the upper side of the throw-away chip 1. 5 is an amplification circuit for the output of the photoelectric conversion element 4.

By moving the throw-away chip 1 in the direction of arrow A while maintaining the angle between the projected light 2 and the side of the chip, the entire end of the throw-away chip 1 forms an image on the photoelectric conversion element 4. will be done. Here, if a chip occurs at the end, the reflected light 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.

However, if the chip happens to be located at the nose R portion 1a of the throw-away chip 1 (which is often the case), the output waveform of the photoelectric conversion element 4 becomes as shown in FIG. Here, X is an output signal due to diffuse reflection at the nose R portion 1a, and a missing signal appears as S. Therefore, it becomes virtually impossible to detect a chip.

Therefore, a signal Y is formed by delaying this output signal by a predetermined period of time, the difference between this output signal and the delayed signal is calculated, and the number of times the difference output becomes larger than a preset level is counted. That is, if the number of occurrences is greater than the number of nose R parts, it can be clearly determined that there is a chip.

That is, as shown in FIG. 4, the output of the photoelectric conversion element 4 is delayed by a delay circuit 6, and is input together with the output to a comparator 7 to extract a difference signal between the two. This difference signal is compared with the threshold level from the set level generation circuit 8 by the comparator 9, and the number of times the threshold level is exceeded is counted by the counter 10, and only when the counted value exceeds the set number of times, the counter 10 What is necessary is just to configure it so that the missing signal a is outputted from. Of course counter 10
is preset at the same time as the output of the missing signal a, and it is desirable that the set number of times setter be of a variable type.

Since the present invention is as described above, it is possible to distinguish the signal of diffuse reflection from the nose R portion of the throw-away chip from the chipping signal without confusing the result, and to accurately determine the presence or absence of chipping.

Further, the setting level for comparing the difference output between the output signal of the photoelectric conversion element and a signal obtained by delaying this output signal by a predetermined time and the comparator 9 is set separately for the side part of the throw-out chip and the nose R part 1a. This allows for even more accurate discrimination.
Note that inspection standards are usually different for the side portion and the nose R portion 1a.

[Brief explanation of the drawing]

Fig. 1 is a configuration diagram of an embodiment of the present invention, Fig. 2 is a plan view thereof, Fig. 3 is an output waveform diagram of the photoelectric conversion element, and Fig. 4 is a diagram of the output waveform of the photoelectric conversion element.
The figure is a block diagram of output signal processing of a photoelectric conversion element. 1... Throw-away chip, 4... Photoelectric conversion element.

Claims (1)

[Scope of Claims] 1. A chip detection device for determining the presence or absence of a chip at the end of an object to be inspected, such as a throw-away chip, which emits light from the side of the object to be inspected and is disposed on the upper surface of the end of the object to be inspected. The end of the object to be inspected is imaged on a narrow strip-shaped photoelectric conversion element, and the output of the photoelectric conversion element when the object to be inspected is moved horizontally while maintaining the angle of the light projection direction prevents chipping. In the device for detecting the presence or absence of A chipping inspection device characterized in that a counter counts the number of times the chipping exceeds a preset level, and determines chipping when the counted value is greater than a preset number of times. 2. A setting level for comparing the difference output between the output signal of the photoelectric conversion element and a signal obtained by delaying this output signal by a predetermined time is set separately for the sides and corners of the object to be inspected. A chipping inspection device according to claim 1.