JP3530382B2 - Square billet surface flaw inspection equipment - Google Patents

Description

Description: BACKGROUND OF THE INVENTION [0001] 1. Field of the Invention [0002] The present invention relates to a square billet surface flaw inspection apparatus which detects a flaw on the surface of a square billet and obtains its position. 2. Description of the Related Art An outline of a square billet surface defect inspection device (hereinafter, referred to as an inspection device) will be described. The inspection device is
It detects small flaws on the surface of a square billet based on the operation principle of magnetic recording flaw detection, and is a kind of a so-called non-destructive inspection device. Here, a square billet usually has a cross section of about 150 mm square, and a length of 10 to several meters to 3 m.
It is a steel material with an elongated shape of about 0 m. If the square billet is magnetized in advance, magnetic flux leaks from the surface flaws, so a magnetic tape (hereinafter referred to as tape) can be brought into contact with the surface of the square billet and this leaked magnetic flux can be recorded as a flaw signal on the tape. it can. The flaw signal recorded on the tape can be taken out in the form of an electric signal by a dedicated sensor, and is sent to a flaw signal processing device separately provided. FIG. 3 is a diagram for mechanically explaining the principle of operation. Reference numeral 1 denotes a square billet, reference numeral 2 denotes a tape, reference numerals 3 and 4 denote rollers, and reference numeral 5 denotes a disk-shaped high-speed rotating rotor (hereinafter referred to as a "rotational rotor"). , Rotor 6), and reference numeral 6 denotes a sensor mounted on the rotor 5. The square billet 1 runs in the direction of the arrow, and the tape 2 circulates in the direction of the arrow. At this time, the square billet 1 comes into contact with the tape 2 at the roller 4 and a flaw signal is recorded on the tape 2 at this time. Is done. There are a total of four sensors 6, while rotating at high speed with the rotor 5,
Each of them detects the flaw signals recorded on the tape 2 in order. FIG. 3 shows that one of the sensors 6a is detecting a signal. On the other hand, the sensor 6
It is necessary to know in real time during the traveling of the angular billet which of the flaw signals detected by (1) the flaw at which position on the surface of the angular billet 1 is due, that is, the current position in the width direction and the traveling direction. First, the widthwise position of the surface of the square billet 1 can be obtained from the current rotational position of the sensor 6. Therefore, the rotary position of the sensor 6 is detected by directly connecting the absolute rotary encoder 7 to the rotor 5. On the other hand, the current position of the angular billet 1 in the traveling direction only needs to know how much the angular billet 1 has advanced from the position where the angular billet 1 is located. For this reason, as shown in FIG. 4, an incremental rotary encoder 9 (hereinafter, referred to as an encoder 9) is provided via a roller 8 so that the encoder 9 rotates as the square billet 1 travels. Then, the flaw signal processing device counts the output pulses of the encoder 9, calculates the actual travel distance by multiplying the result (integrated value) by the angular billet travel distance per pulse, and calculates the actual travel distance. I'm looking for my current location. In FIG. 4, reference numeral 10 denotes a sensor such as a photoelectric switch or a limit switch, which detects that the tip of the square billet 1 has reached that position. When the angular billet 1 reaches the position of the sensor 10, the encoder 9 is already operating. The distance Lo between the sensor 10 and the position where the tape 2 contacts the square billet 1 at the roller 4 is constant, and the value is known in advance. The distance L after the square billet 1 comes to the position of the sensor 10
It is possible to detect the timing when the vehicle travels by the distance o. In this way, the flaw data recorded on the tape 2 is synchronized with the position in the traveling direction of the square billet 1. In FIG. 4, when the angular billet 1 reaches a certain position, the angular billet 1 comes off the encoder 9. Therefore, two sets of the encoders 9 are attached to the entrance side and the exit side of the inspection device like the encoders 9a and 9b, respectively, and are switched at appropriate timing. In the prior art, the position of the angular billet 1 in the traveling direction was detected by using the encoder 9, but there was a problem that the detection accuracy was not sufficient. This is because the encoder 9 for detecting the position in the traveling direction itself has a limit in accuracy.
This is because a detection error occurs due to (1) irregularities on the surface of the square billet 1, (2) roundness of the roller 8, (3) slippage between the square billet 1 and the roller 8, and the like. Was. Moreover, this error has the property of being accumulated and increasing one after another in the process of counting the pulse signals, and the upper angle billet 1 has a total length as long as 10 m to 30 m. The problem with detection accuracy was severe. The present invention has been made in view of the above circumstances, and provides a corner billet surface flaw inspection apparatus capable of detecting the position of a corner billet in the traveling direction with extremely high accuracy and accurately determining the position of a flaw. It is intended to be. In order to achieve the above object, a surface defect inspection apparatus for a square billet according to the first aspect of the present invention includes a roller for supporting the square billet movably in a longitudinal direction, and the roller. A flaw detecting means for detecting flaws on the surface of the square billet traveling on the top, an encoder provided on the roller for detecting the amount of rotation of the roller, and a gap provided along the traveling direction of the square billet A plurality of sensors for detecting that the angular billet has arrived, and arithmetic means for calculating a position of a flaw detected by the flaw detection means from detection signals of the encoder and the sensor, wherein the calculation means comprises: The square billet corresponds to each sensor
When the sensor reaches the position where
Output to reset the encoder, the seat of the sensor
Replace the mark as the current position in the direction of the corner billet,
By adding the subsequent movement amount of the square billet to the coordinates of the starting point with that position as the starting point ,
The sensor that passed the current position in the
The position of the square billet is calculated by using the position of the corner bill as a starting point, and the traveling direction position of the square billet is obtained. In other words, since the detected value of the movement of the angular billet by the encoder is reset once when the angular billet reaches each sensor, the maximum value of the detected value of the movement of the angular billet by the encoder is the distance between the sensors. It is said. That is, the detection amount of the movement amount of each billet by the encoder is shortened, and thereby, the detection error of the movement amount of the square billet is suppressed. An embodiment of the present invention will now be described with reference to the accompanying drawings. FIG. 1 shows a square billet surface flaw inspection apparatus (hereinafter, referred to as an inspection apparatus) according to the present embodiment. This inspection device includes:
A plurality of position detection sensors 10, 11, 12, 13, 14, and 15 are provided at intervals along the traveling direction of the angular billet 1.
3, 14, and 15, the traveling angular billet 1 is sequentially detected. That is, the angular billet 1 advances and the respective sensors 10, 11, 12, 13, 1
4 and 15, the sensors 10, 11, 12, 13, 14, and 15, which have reached the angular billet 1, receive the angular billet 1.
Are sequentially detected, and a detection signal is output from the sensor. Then, these sensors 10, 11, 1
The position of the angular billet 1 is obtained by the calculating means based on the detection data from the encoders 2, 13, 14, 15 and the encoder 9. The other parts have substantially the same structure as the above-mentioned conventional apparatus. However, in this embodiment, reference numeral 2 denotes a tape, reference numerals 3 and 4 denote rollers, and reference numeral 5 denotes a disk-shaped high-speed rotating rotor (hereinafter, referred to as a rotor). Reference numeral 6 denotes a sensor mounted on the rotor 5, the square billet 1 runs in the direction of the arrow, and the tape 2 circulates in the direction of the arrow.
Since the square billet 1 comes into contact with the tape 2 at the roller 4, a flaw signal is recorded on the tape 2 at this time. There are a total of four sensors 6, which rotate at high speed together with the rotor 5, each of which detects a flaw signal recorded on the tape 2 in order. The position of the surface of the square billet 1 in the width direction is obtained by detecting the rotational position of the sensor 6 by an absolute type rotary encoder 7 provided on the rotor 5. The position in the traveling direction of the square billet 1 is determined by an incremental rotary encoder 9 provided via a roller. The tape 2, the rollers 3, 4, the rotor 5, the sensor 6, and the absolute rotary encoder 7 constitute a flaw detecting device (flaw detecting means) 21. Next, how to detect the position of the angular billet 1 in the traveling direction by the calculating means will be described. The square billet 1 has the respective sensors 10, 11, 12, 13, 14,
When the sensor reaches the position corresponding to No. 15, the corresponding sensor outputs a detection signal. Then, the current position in the traveling direction of the angular billet 1 is calculated from the output pulse count value of the encoder 9 with the position of the last sensor that passed at that time as the starting point. That is, in FIG. 2, when the tip of the square billet 1 is located between the sensor 10 and the sensor 11 as at the point A, the distance calculated based on the count value of the output pulse of the encoder 9 starting from the origin O. L1a becomes the current position as it is. Next, when the angular billet 1 further advances and reaches the position of the sensor 11, the pulse count value of the encoder 9 is reset, and the coordinates (distance from the origin O) L1 of the sensor 11 are replaced as the current position. . Next, when the tip of the square billet 1 is located between the sensor 11 and the sensor 12 like the point B, the distance L2 calculated from the output pulse count value of the encoder 9 starting from the coordinate L1 of the sensor 11 is used.
The value obtained by adding a to the coordinate L1 is defined as the current position. The angular billet 1 further advances to point C, D
Even at the positions of the points E, F, and F, the pulse count value is reset and the counting is started again at the point when each of the sensors 12, 13, 14, and 15 has passed, similarly to the case of the point B. The result obtained by adding the new count value to the distance from the origin O (coordinates in the traveling direction) is the current position. Similarly, at points between the sensors 12, 13, 14, and 15 and beyond the sensor 15, similarly to the above, the output pulse count value of the encoder 9 starting from the coordinates of the sensor immediately after the square billet 1 has passed. The value obtained by adding the calculated distance to the coordinates of the sensor is defined as the current position. Here, the method of detecting the distance after reaching the position of the sensor 12 at the tip of the square billet 1 is as follows. (1) Sensor 12 When the tip of the square billet 1 reaches the sensor 12, the pulse count value of the encoder 9 is reset, and the coordinates L1 + L2 of the sensor 12 are replaced as the current position. (2) When the tip of the billet 1 between the sensors 12 and 13 is located between the sensor 12 and the sensor 13 as at the point C, the coordinates L1 + L2 of the sensor 12
The value obtained by adding the distance L3a calculated from the output pulse count value of the encoder 9 starting from to the coordinates L1 + L2 is defined as the current position. (3) Sensor 13 When the tip of the square billet 1 reaches the sensor 13, the pulse count value of the encoder 9 is reset, and the coordinates L1 + L2 + L3 of the sensor 13 are replaced as the current position. (4) When the tip of the billet 1 between the sensors 13 and 14 is located between the sensor 13 and the sensor 14, such as the point D, the coordinates L1 + L2 of the sensor 13
The value obtained by adding the distance L4a calculated from the output pulse count value of the encoder 9 starting from + L3 to the coordinates L1 + L2 + L3 is defined as the current position. (5) Sensor 14 When the tip of the square billet 1 reaches the sensor 14, the pulse count value of the encoder 9 is reset, and the coordinates L1 + L2 + L3 + L4 of the sensor 14 are replaced as the current position. (6) When the tip of the billet 1 between the sensors 14 and 15 is located between the sensor 14 and the sensor 15 like the point E, the coordinates L1 + L2 of the sensor 14
The distance L5a calculated from the output pulse count value of the encoder 9 starting from + L3 + L4 is represented by coordinates L1 + L2 + L.
The value added to 3 + L4 is set as the current position. (7) Sensor 15 When the tip of the square billet 1 reaches the sensor 15, the pulse count value of the encoder 9 is reset, and the coordinates L1 + L2 + L3 + L4 + L5 of the sensor 15 are replaced as the current position. (8) When the tip of the square billet 1 after the sensor 15 is located at a point beyond the sensor 15, such as point F, the coordinates of the sensor 15 are L1 + L2 + L3 +
The distance L6a calculated from the output pulse count value of the encoder 9 starting from L4 + L5 is represented by coordinates L1 + L2 + L3.
The value added to + L4 + L5 is set as the current position. As described above, according to the inspection apparatus, the output pulse count value of the encoder 9 can be obtained by the sensors 10, 11,
Since the count distance is reset once when it reaches 12, 13, 14, and 15, the maximum value of the count distance does not exceed L1, L2, L3, L4, and L5 in FIGS. That is, in the conventional technique, the counting is continued over almost the entire length of the square billet 1, but according to the inspection device of the embodiment, the counting distance can be much shorter. As a result, even if the error is accumulated and increased in the process of counting the pulse signal, the value can be kept extremely small as compared with the conventional case. Also, sensor 1
Since the positions of 0, 11, 12, 13, 14, and 15 can be accurately set, the coordinates of the same sensor used for calculating the current position can also have sufficient accuracy. Therefore,
The position detection accuracy in the traveling direction of the angular billet 1 can be greatly improved as compared with the related art. As described above, according to the square billet surface flaw inspection apparatus of the present invention, the detected value of the amount of movement of the square billet by the encoder is determined when the square billet reaches each sensor. Therefore, the maximum value of the detected value of the amount of movement of the angular billet by the encoder can be used as the distance between the sensors. In other words, the detected value of the amount of movement of the angular billet by the encoder can be significantly reduced as compared with the conventional device in which the amount of movement of the angular billet is detected over the entire length of the angle billet by the encoder. .
As a result, in addition to the limit on the accuracy of the encoder itself, it is possible to suppress the detection error of the movement amount due to the unevenness of the surface of the square billet, the roundness of the roller, the slip between the square billet and the roller, and the like. In other words, the position in the traveling direction of the square billet can be detected with extremely high accuracy,
The detection position of the flaw by the flaw detection means can be obtained with extremely high accuracy. [0023]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic perspective view of an inspection device for explaining a configuration and a structure of a square billet surface defect inspection device according to an embodiment of the present invention. FIG. 2 is an explanatory diagram illustrating a detection method by the square billet surface flaw inspection device according to the embodiment of the present invention. FIG. 3 is a schematic perspective view of an inspection device for explaining a configuration and a structure of a square billet surface defect inspection device. FIG. 4 is a schematic perspective view of a square billet surface flaw inspection apparatus provided with means for detecting a position of a square billet in a traveling direction. [Description of Signs] Single Square Billet 8 Roller 9 Encoder 10, 11, 12, 13, 14, 15 Sensor 21 Flaw Detection Device (Flaw Detection Means)

Claims (1)

(1) A roller for supporting a rectangular billet movably in a longitudinal direction, a flaw detecting means for detecting a flaw on a surface of the rectangular billet traveling on the roller, and the roller Provided in
An encoder that detects the amount of rotation of the roller, and a plurality of sensors that are provided at intervals along the traveling direction of the angular billet and detect that the angular billet has arrived,
Calculating means for calculating the position of the flaw detected by the flaw detecting means from the detection signals of the encoder and the sensor, wherein the calculating means determines when the angular billet reaches a position corresponding to each of the sensors. Is detected by the sensor.
And outputs the output signal resets said encoder, the cell
The coordinates of the sensor as the current position in the traveling direction of the square billet.
Instead it can, by adding the amount of movement of the subsequent square billet its position as a starting point to the coordinates of the start point, the angle bi
The current position in the direction of travel of the let
An angle billet surface defect inspection device, wherein the position of the traveling direction of the angle billet is obtained by calculating the position of the sensor as a starting point .