JPH08136471A - Self-diagnosing apparatus for surface defect detector - Google Patents

Abstract

PURPOSE: To judge whether there is a functional trouble or not in a detecting part by comparing the crack information based on reflected light in the surface of a crack sample with the flaw information of a flawed sample stored previously. CONSTITUTION: When a standard forming mode of a self-diagnosis relating instruction means 75 is selected, a self-diagnosis control part 77 receives a signal of the means 75 and inform a detection part 51, a selector 61, and a signal processing part 62 of the setting of a standard formation. The detection part 51 starts driving the diagnosing mechanism part and sends the flaw signal to the processing part 62 through the selector 61, based on the reflected light on the surface of a flawed sample. After carrying out differentiation process for the flaw signal, the processing part 62 extracts the quantity of the characteristic of the flaw and stores the result in a standard memory 63. Then, when a self-diagnosis mode of the means 75 is selected, from the detecting part 51 to the processing part 62 operate in the same way and the quantity of the characteristic of a flaw is stored in a present time memory 65. The data of the standard memory 63 and that of the present time memory 65 are compared mutually and a data processing part 69 judges that a functional trouble does not exist (exist) in the detection part 51 if these is (is not) the identity of both data.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a surface defect meter for inspecting the surface of an object to be inspected in a plate-shaped strip made of, for example, a steel plate or aluminum to detect defects in the object to be inspected.

[0002]

2. Description of the Related Art FIG. 5 is an explanatory view for explaining an inspection method using a conventional surface defect meter. In the figure, reference numeral 1 denotes a detector, which includes a laser tube 3 that oscillates a laser, a rotary mirror 7 that reflects the laser emitted from the laser tube 3 and scans the surface of the inspection object 5, and a surface of the inspection object 5. A condenser lens 9 that collects the reflected light, a high-sensitivity mask 11 that removes noise from the light condensed by the condenser lens 9, and a photomultiplier tube 1.
3. The detector 15 for detecting only the defect signal from the photoelectrons multiplied by the photomultiplier tube 13 and the preamplifier 17 for amplifying the signal output from the detector 15 are provided.

Further, reference numeral 21 is a signal processing unit for extracting a feature amount of a flaw after subjecting the flaw signal output from the detection unit 1 to differential processing and wave height discrimination processing. Further, reference numeral 23 denotes a data processing unit, which determines a flaw type and a grade from the feature amount, displays the determination result on the CRT 25 as quality assurance information,
The printer 27 outputs it to a form, and further outputs it to the defect monitor 28. In addition, the data processing unit 2
3 receives an input from an external device 29 that performs inspections other than flaws, and displays an inspection result based on the input data on the CRT.
It also has a function of outputting to 25 or the like.

Next, the operation of the conventional surface defect meter constructed as above will be described. In the detection unit 1, the laser light oscillated from the laser tube 3 is scanned by the rotating mirror 7 to irradiate the surface of the object 5 to be inspected, and the reflected light is collected by the condenser lens 9 and then covered by the high sensitivity mask 11. Noise different depending on the surface roughness of the inspection object 5 is removed, and only the flaw signal is detected by the detector 15 and transmitted to the signal processing unit 21. In addition, the signal processing unit 2
In No. 1, the data processing unit 2 extracts the feature amount of the flaw after performing the differential processing and the wave height discrimination processing on the flaw signal as described above.
Send to 3. Further, the data processing unit 23 determines a flaw type or a grade from the feature amount, displays the determination result as quality assurance information on the color CRT 25, and outputs it on a form by the printer 27.

[0005]

However, the conventional surface defect meter as described above does not have a diagnostic function capable of immediately detecting a functional disorder of the detection unit 1 of the surface defect meter,
In order to check whether the function of the detection unit 1 is normal, the operator installs a flaw sample on the inspection line, scans the flaw sample, and investigates whether or not the flaw indicated in the flaw sample can be detected. Had to diagnose by doing. Therefore, in diagnosis, the line must be stopped and the above-described work must be performed, and this work requires a long time, which causes a decrease in product production efficiency. Further, in order to diagnose whether or not the surface defect meter normally exerts a detection function for various flaws, it is necessary to scan a plurality of different flaw samples by the above method, which requires a longer time. It was.

A technique relating to a pinhole tester self-diagnosis device for inspecting a pinhole of an aluminum can using a light source is disclosed in Japanese Patent Laid-Open No. 64-79647. As shown in FIG. 6, the device disclosed in this publication irradiates light from a light source 30, and of this light, light leaking from a test pinhole 33 provided in a turret disk 31 is transmitted to an optical sensor 35. Whether or not the detection system operates normally is determined by whether or not it is detected. However, according to the publication, a surface defect of the inspection object is irradiated by irradiating the surface of the inspection object having a plate-shaped band with light, converting the diffracted light reflected from the surface into an electric signal, and adding various weights. 5 to inspect
In principle, it cannot be applied to the surface defect meter shown in. For the above reasons, it has been desired to develop a self-diagnosis device for a plate-shaped band surface defect meter.

The present invention has been made to solve the above problems, and an object thereof is to provide a self-diagnosis apparatus for a surface defect meter.

[0008]

A self-diagnosis apparatus for a surface defect meter according to the present invention irradiates a surface of an object to be inspected in a plate-shaped band with light, receives light reflected from the surface, and further receives the reflected light. In a surface defect meter that detects a flaw signal from the detected light by a detection unit and inspects the surface defect of the inspected object based on the detection signal of the detection unit, a storage unit that stores the flaw information of at least one kind of flaw sample; Based on the reflected light reflected on the flaw sample surface, and a diagnostic holding unit having a sample holding section for holding a flaw sample and a mirror group for reflecting the reflected light reflected on the flaw sample surface to enter the light receiving section It is provided with a judgment means for comparing the defect information with the defect information of the defect sample stored in the storage means to judge the presence / absence of a functional disorder of the detection unit.

The sample holder is movably attached to a detection position intersecting the optical path of the irradiation light and a standby position out of the optical path of the irradiation light, and the mirror group reflects the reflected light reflected by the flaw sample. A fixed mirror that changes the course of
The detection position intersecting the optical path of the reflected light reflected by the fixed mirror and the standby position deviated from the optical path of the reflected light reflected by the object to be inspected are movably installed, and the fixed position is set at the detection position. And a movable mirror for changing the path of the light reflected by the mirror so as to enter the light receiving unit.

Further, the diagnostic mechanism section is installed so that it can be freely taken in and out above an object to be inspected while online.

[0011]

In the self-diagnosis device for the surface defect meter constructed as described above, the flaw information based on the reflected light reflected on the flaw sample surface and the flaw information of this flaw sample are stored in advance in the storage means. By comparing with
It is determined whether or not the detection unit has a functional disorder.

The sample holder moves between the detection position and the standby position, and the movable mirror changes the path of the light reflected by the fixed mirror so as to enter the light receiver.
The detection position and the standby position are moved. By such movement of the sample holder and the movable mirror, self-diagnosis can be appropriately performed.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is a block diagram of an embodiment of the present invention, and FIGS. 2 and 3 are explanatory views for explaining a part (detection section) of FIG. 1, in which a conventional example is shown. The same parts as those in FIG. 5 are designated by the same reference numerals and the description thereof will be omitted. Reference numeral 51 denotes a detection unit, which includes a diagnosis mechanism unit 53 in addition to the detection unit 1 shown in FIG. 5, and this diagnosis mechanism unit 53 has a sample holding unit 55 to which a flaw sample is attached as shown in FIG. It is composed of a fixed mirror 57 installed above the holding unit 55 and a movable mirror 59 installed forward of the installation position of the fixed mirror 57 in the rolling direction. The sample holder 55 and the movable mirror 59 are reciprocally movable in the rolling direction as shown by the arrows in FIGS.
In addition, the sample holder 55 is configured so that various flaw samples can be set by a rotary or slide actuator.

Reference numeral 61 is a selector for selectively switching the passage of the output signal of the detection unit 51 according to each state of measurement, diagnosis, and standard, and 62 is a signal processing unit, which is a function of the signal processing unit 21 shown in the conventional example. In addition to the standard memory 63, this time memory 6
5 and comparison data creating means 67. The reference memory 63 is a storage unit that scans a flaw sample in advance and data-converts and stores the result, the current memory 65 is a storage unit that stores the scanning result of the flaw sample at the time of diagnosis, and the comparison data creating unit 67 is the reference memory 63. And the data stored in the memory 65 this time are compared to create comparison data.

Reference numeral 69 denotes a data processing unit, which in addition to the function shown in the conventional example, determines whether or not the detection unit 51 has a functional failure based on the data created by the comparison data creating unit 67 and creates a normal signal or an abnormal signal. The determination means 70 is provided. Reference numeral 73 is an alarm that receives an abnormality signal from the determination means 70 and notifies the operator of the occurrence of abnormality by a buzzer or voice. Reference numeral 75 is a self-diagnosis related command means for outputting a self-diagnosis start command signal for instructing the start of self-diagnosis based on an operator's instruction or a standard data creation command signal for instructing the creation of standard data to be described later. In response to the signal from the means 75, the self-diagnosis related command signal (self-diagnosis start command signal or reference data creation command signal) is detected by the detection unit 5.
1, a self-diagnosis control unit for outputting to the signal processing unit 62 and the data processing unit 69.

Next, the types of flaw samples installed in the sample holder 55 and their data processing will be described.
FIG. 4 shows a real image (a) of a flaw sample and a profile image (b) obtained by digitally processing the real image. There are various kinds of flaw samples, but in the present embodiment, flawless 81, bald defects 82, picked defects 83, gouge defects 84, multi-line defects 85, surface defects 86 and loki defects 87 are present. It is adopted. Hereinafter, the operation of creating the profile image (b) of the flaw sample will be described by taking the bald defect 82 as an example. The scanning method is a method in which the irradiation light is scanned in the width direction (X) of the flaw sample with pixel dimensions n1, n2, ..., And is sequentially moved in the length direction (Y) with N1, N2.

In the scanning of N1 and N2 in FIG. 4 (a), there is no defective portion, so there is no profile data. Also, N
In the scans of 3 and N4, there are defects in n4 to n5,
Two histograms are obtained on the X axis of the profile data and one histogram is obtained on the Y axis. Furthermore, in the scan of N5 to Ni, there is only a defect related to n4, and the X axis of the profile data is 1
And one histogram on the Y axis. Further, since there is no defective portion at the scanning end of N0, there is no profile data. As described above, the profile image (b) is obtained by scanning the actual image (a) in the width direction with the pixel size and integrating the signal levels equal to or larger than the pixel size in the length direction.

Next, the operation of scanning a flaw sample for data processing and storing it in the reference memory 63 will be described.
When the operator selects the standard creation mode in the self-diagnosis related command means 75, the self-diagnosis related command means 75 outputs a signal to that effect to the self-diagnosis control unit 77. The self-diagnosis control unit 77 receives the signal from the self-diagnosis related command means 75 and notifies the detection unit 51, the selector 61, and the signal processing unit 62 that there is a standard preparation instruction. When the detection unit 51 receives the notification from the self-diagnosis control unit 77, the diagnosis mechanism unit 53 moves the sample holding unit 55 and the movable mirror 59 and arranges them as shown in FIG. Further, the selector 61 is the self-diagnosis control unit 7
When the notification of 7 is received, the signal path is set so that the signal output from the detection unit 51 is input to the reference memory 63.

When the above setting is completed, laser light is emitted from the laser tube 3 and the sample holding section 55 moves at a predetermined speed in the rolling direction to start scanning. The irradiation light reflected by the flaw sample 54 is reflected by the fixed mirror 57 and the movable mirror 59 and is incident on the light receiving unit 13 via the condenser lens 9. In the light incident on the light receiving unit 13, only the flaw signal is detected by the detector as in the case of the conventional example, and is transmitted to the signal processing unit 62 via the selector 61. In addition, the signal processing unit 62 performs differentiating processing, wave height discrimination processing, and the like on the flaw signal, then extracts the feature amount of the flaw, creates the profile as described above, and stores it in the reference memory 63. By the same operation, the data on the defect sample shown in FIG. 4 is stored in the reference memory 63.

A normal rolling line is operated with the defect sample data stored in the standard memory 63 as described above. In this case, the sample holding section 55 and the movable mirror 59 are located at the positions shown in FIG. It is located in. Next, the operation at the time of self-diagnosis will be described. When the operator selects the self-diagnosis mode in the self-diagnosis related command means 75, the self-diagnosis related command means 75 outputs a signal to that effect to the self-diagnosis control unit 77. The self-diagnosis control unit 77 receives the signal from the self-diagnosis related command means 75 and notifies the detection unit 51, the selector 61 and the signal processing unit 62 that the self-diagnosis instruction has been given. When the detection unit 51 receives the notification of the self-diagnosis control unit 77, the diagnosis mechanism unit 53 causes the sample holding unit 55 and the movable mirror 59 to be similar to the case of the above-described reference creation mode.
Are moved and arranged as shown in FIG. Further, when the selector 61 receives the notification from the self-diagnosis control unit 77, the detection unit 5
The signal path is set so that the signal output from 1 is input to the memory 65 this time. When the above setting is completed, scanning is started, and the irradiation light reflected by the flaw sample 54 is processed by the signal processing unit 62 in the same manner as in the case of the standard creation mode described above.
Sent to, the profile is created and now memory 65
Stored in.

Next, the comparison data creating means 67 receives the instruction of the self-diagnosis control section 77 and calls the data (profile) stored in the reference memory as the same as the flaw sample scanned in the self-diagnosis mode. Then, the called data is compared with the data stored in the memory 65 this time, and the comparison data is transmitted to the data processing unit 69. In the data processing unit 69, the judging unit 70 determines the detection unit 51 based on a certain standard based on the input comparison data.
To determine if there is a functional disorder. That is, if the data in the reference memory and the data in the current memory have the same identity, there is no functional failure, and if there is no identity, it is determined that there is a functional failure. And when it is judged to be normal, create a normal signal,
A message indicating that there is no functional failure is displayed on the CRT 25. On the other hand, when it is determined to be abnormal, an abnormal signal is generated and output to the alarm 73, and detailed information is displayed or output to the color CRT 25 or the printer 27.

In the above embodiment, the operator selects the self-diagnosis mode in the self-diagnosis related command means 75 as the condition for starting the self-diagnosis, but the present invention is not limited to this. For example, the number of rolled sheets may be counted and the self-diagnosis related command means 75 may output a self-diagnosis start signal when a predetermined number of sheets are rolled. Alternatively, the rolling time may be counted and a self-diagnosis start signal may be output when a predetermined operating time has elapsed.

[0023]

As described above in detail, according to the present invention, the flaw information based on the reflected light reflected on the flaw sample surface and the flaw information stored in advance in the storage means as the flaw information of this flaw sample are provided. Since the presence / absence of a functional disorder in the detection unit is determined by comparison, the self-diagnosis of the surface defect meter for inspecting the surface defect of the inspected object of the plate-shaped band becomes possible.

Further, since the sample holder and the movable mirror are installed so that the detection position and the standby position can be moved, self-diagnosis can be appropriately performed.

[Brief description of drawings]

FIG. 1 is a block diagram of one embodiment of the present invention.

FIG. 2 is an explanatory diagram for explaining a part (detection unit) of FIG.

FIG. 3 is an explanatory diagram for explaining a part (detection unit) of FIG. 1.

FIG. 4 is a diagram showing a real image (a) of a flaw sample and a profile image (b) obtained by digitally processing the real image.

FIG. 5 is an explanatory diagram illustrating an inspection method using a conventional surface defect meter.

FIG. 6 is an explanatory diagram illustrating a conventional self-diagnosis device for a pinhole tester.

[Explanation of symbols]

 51 detection unit 62 signal processing unit 63 standard memory 65 current memory 67 comparison data creation unit 69 data processing unit 70 determination unit 75 self-diagnosis related command unit 77 self-diagnosis control unit

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Nobuaki Satake 1-2-1, Marunouchi, Chiyoda-ku, Tokyo Nihon Steel Pipe Co., Ltd.

Claims (3)

[Claims] 1. A plate-shaped belt surface to be inspected is irradiated with light, the light reflected by the surface is received by a light receiving section, and a flaw signal is detected by the detecting section from the received light. In a surface defect meter for inspecting a surface defect of an object to be inspected based on a signal, a storage means for storing defect information of at least one kind of defect sample, a sample holding section for holding the defect sample and a defect sample surface A diagnostic mechanism unit having a mirror group for reflecting reflected light to enter the light receiving unit, defect information based on the reflected light reflected on the defect sample surface, and defect information of the defect sample stored in the storage unit. A self-diagnosis device for a surface defect meter, comprising: a determination means for comparing and determining whether or not there is a functional disorder in the detection part. 2. The sample holder is movably attached to a detection position intersecting the optical path of the irradiation light and a standby position deviated from the optical path of the irradiation light, and the mirror group reflects light reflected by a flaw sample. A fixed mirror that changes the path of the optical path, a detection position that intersects the optical path of the reflected light reflected by the fixed mirror, and a standby position that is deviated from the optical path of the reflected light reflected by the object to be inspected are movably installed. The self-diagnosis device for a surface defect meter according to claim 1, further comprising: a movable mirror that changes a path of the light reflected by the fixed mirror so as to enter the light receiving unit at the detection position. 3. The self-diagnosis apparatus for a surface defect meter according to claim 1, wherein the diagnostic mechanism section is installed above and below the object to be inspected while being online.