JPS5876745A - Flaw detector - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an apparatus for detecting surface flaws on objects to be detected such as metal plates and plastic snack plates.

As shown in FIG. 1, a +J cut was made on the surface of a plate 1, such as a metal plate or a plus-J plate. There are minute surface scratches, like scratches, in the form of notches. l, J<Once upon a time that board 1
It is difficult to identify the surface flaw a with the naked eye unless you look through the plate 1, and there is no certainty. Congratulations on using it during measurement! 11f illumination method is adopted. That is, light is irradiated onto the surface of the tentative person from an oblique direction as shown by the arrow, and the light detected by the surface flaw a is reflected in one direction, causing the surface flaw a to emerge. However, as shown in FIG. 2, the surface scratches on the plate 10 are al, a2. Each surface scratch a1. a2゜a3 every r(
It is necessary to change the direction of the light so that it hits the scratch from a direction perpendicular to it, and then detect the reflected light. In particular, when it is necessary to illuminate a wide field of view, such as for industrial boards, the lighting equipment becomes large and difficult to install. -! , Ta 1 = It was difficult to detect minute scratches a with the method described above.

The present invention eliminates the drawbacks of the conventional art and makes it easy to remove various surface scratches on objects to be detected using a single light source.

We provide a complete set of flaw detection devices that can detect defects reliably, and that the entire device can be assembled into a single unit for ease of handling and lower costs. The purpose is to

The present invention achieves the following two objects: 1', the incident light from the source is deflected in a predetermined direction with respect to the detection surface of the crocodile object by the first mirror; 1(, (Anti Q1 Ha:
4.The second mirror reflects and irradiates the detection surface in the direction of the gradient (2, i, 1st direction, and the scratches on the detection surface<,bright part,!,:
I, , T- is characterized by detecting (
Uzl.

The present invention will be explained in detail with A and 118 fruiting examples.

FIG. 3 is a cross-sectional view of the palm part of the embodiment of FIG. A lens 4 and a lens 4 for condensing the reflected light of the auto linear array (
A binarization converter that processes the output 4 of this Kyuden detection element r3 (commonly known as a line sensor), etc. A mirror box 6t1 is provided integrally with the mirror box 6, and is a mirror on the other side.・Niri (.

It is installed at a 4 pin angle. 9t1. Lighting 1 earth light source, 10: Collection of v4) from the above light source) 15
Y, Lens, 7t, 1 At the bottom of the mirror box 5, there is an inverted cone whose diameter gradually decreases as it moves away from the planar first reflecting mirror 6. This is a second reflecting mirror for scattering light having a reflecting surface of the shape of . Note that the first reflecting mirror 6 has a transparent central portion 6' to allow light to pass through to the photoelectric element 1. Reference numeral 11 denotes a light-transmitting section made of transparent glass or the like, provided in front of the condensing lens 10 and coaxially therewith.

Next, the operation of this embodiment will be explained. The light from the light source 9 is passed through a condensing lens 10. After passing through the light-transmitting part 11, it is reflected downward at the periphery of the first reflecting mirror 6, and then reflected again by the second reflecting mirror T, from an obliquely upper side of the measurement object 1.
15 is irradiated. 1lIII Of the reflected light from the constant object 1, the component perpendicular to the measurement object 1 passes through the first reflection mirror 6, is focused by the condensing lens 4, is detected by the photoelectric detection element 3, and is detected by the photoelectric detection element 3. The relationship between the level of the signal, which is extracted as an electrical signal through the value converter 3', and the presence or absence of scratches is determined by the fourth method.
As shown in the figure.

In Fig. 4A, 12 indicates the ○ level, 14 indicates the slice level, 15i1 indicates the actual electrical signal level (detection level), and the scanning of the Y4 electrical detection element 3 is from left to right in the figure. If there are no scratches on the surface of the measurement object 1, the scattering of -1, direction/\\>Y4&:1. 'fJ
: Because it is, detection level 15f:I:l″r, p*:○
The dark level will be close to . But that 1llll jY thing 1
There is a scratch on the surface of the sea urchin, as shown by A in the same figure.At that point, the scattered light increases rapidly and exceeds the slice level 14.

The output of lL'j,I,',i of C is binarized and the binarization converter 3/, 1: (') is taken Ili 4! -t, I,
As shown in Figure B, the output is digital (l'i'j;, -C(IC)).

According to the above embodiment, the second mirror of the light meter 9 or 1) reflects the light Q1, and the light Q1 can be emitted from diagonally above in multiple directions in the outer peripheral direction of the #III'Ml object 1. No matter which direction the scratch is facing, there is always 111 scattered light.
It has 11 advantages.

Note that the mirror box 6 has a small size 11. (S7.)/In addition to the inverted cone, multiple plane irregularities fE:; V
It may be divided into C and configured as a polyhedron. An external view of another embodiment using such a polyhedral reflecting mirror 7' is shown in FIG. 6.

In the figure, 2' is a detecting power sensor, 5' is a mirror box, 7' is a polyhedral reflecting mirror, 8' is a support for a light source 9' by an illumination lamp, 11' is a transparent part, and 12 is a photoelectric detection element 3.
A cable 14 connects the processor 13 and the processor 13, and 14 is a support stand for the device.

According to this embodiment, the entire device can be compactly packaged, and by simply placing it in front of the measuring object 1, it is possible to reliably detect flaws on the measuring object 1, which moves at high speed. In this case, reflective mirror 6.7 is used,
Instead of this, deflection means such as a prism may be used.

As is clear from the above description, according to the present invention, the light from the light source is deflected toward the detected surface of the detected object by the first optical system, and this reflected light is deflected toward the detected surface by the second optical system. Since the irradiation is deflected in an oblique direction, it is easy to remove various surface scratches with just one light source.

Moreover, it can be detected reliably. In addition, since the entire device can be compactly stored in one unit, handling can be facilitated, and there are advantages such as the ability to achieve a low c-1, :J strike.

[Brief explanation of the drawing]

Figure 1 is an explanatory diagram of the relationship between the surface flaws on the object to be detected and Ichiko's detection illumination, Figure 2 &:1: A plan view showing the surface flaws on the 111 object, and Figure 3 &J tree. In Embodiment 1 of the invention, a cross-sectional view of the flaw detection device, Fig. 4 A, J, an output signal waveform diagram of the 1st υ section, Fig. -11...Object to be detected, 2...Detection horn mela, 3...Photoelectric detection element, 4...Lens, 5...Mirror box, 6...first reflecting mirror, 7...second reflecting mirror, 9...
...) Y, di bottle a... scratches.

Claims (5)

[Claims] (1) A first optical means that deflects the light emitted by the light source in the direction of the detected surface of the detected object; and a first optical means that reflects the light from the first optical means in a diagonal direction with respect to the detected surface. 2nd irradiation
What is claimed is: 1. A flaw detection device comprising: an optical system; and means for detecting a flaw to be detected as a bright area. (2) A line sensor camera is used as a means for detecting flaws on the surface to be detected, and the slice level for light/dark discrimination of the line sensor is set based on the dark level of the reflected light from the surface to be detected;
The flaw detection device according to claim 1, characterized in that reflected light from flaws on the detection surface is detected as a bright level. (3) A reflecting mirror is used as the first optical system, and the reflecting mirror is provided with a portion that creates a vortex between the reflected light from the scratches on the detection surface and the line sensor camera. Flaw detection device as described in section. (4) The second optical system (d) The first optical system (1) is formed in the shape of a circular button whose diameter gradually decreases as the distance increases. ll, τ′1..l
lI water range The flaw detection device according to item 2 or 3. (5) A plurality of 1/1 rlj f! as the second optical system.
+! ? Used in combination with i” polygonal trapezoidal shape 4-1
t11-Practical 1jJl Draft Registration Scope of Claim 2 71. taiL No. a JJ: The flaw detection device according to i.