JP2011017656A - Defect inspection apparatus for metal material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a defect inspection apparatus for metal materials for inspecting defects which occur in the surface and inside of a metal material as continuously feeding the metal material.SOLUTION: The defect inspection apparatus for metal materials includes a transfer device 9 for mounting a metal material 1 on its surface and continuously transferring the metal material 1 in a longitudinal direction D1, a detection head 3 having a plurality of detectors 2 arranged in a row in such a way as to face the surface of the metal material 1 for detecting defects in the metal material 1, and a support device 8 for supporting the detection head over the metal material 1 and reciprocating the detection head 3 in width directions D2. The defect inspection apparatus for metal materials thereby inspects defects which occur in the surface and inside of the metal material 1 as continuously feeding the metal material 1.

Description

  The present invention relates to a defect inspection apparatus for a metal material that inspects defects generated on the surface or inside of the metal material.

  A metal material defect inspection apparatus inspects defects such as scratches and foreign matters generated on the surface or inside of a metal material. In general, each time the detector scans in a direction perpendicular to the feeding direction of the metal material, the detector stops for a predetermined time. While the detector is stopped for a predetermined time, the machine base on which the metal material is placed is intermittently extended with respect to the surface of the metal material in synchronization with the detector stop time. Just move. By repeating this, the defect inspection apparatus for a metal material can inspect defects generated on the surface or inside of the metal material.

  In Patent Document 1, a detector for inspecting a defect on a metal surface is reciprocated in a direction orthogonal to the inspection direction, and stopped for a short time at the scanning end for each scan. A defect detection method for a metal surface is disclosed in which the metal surface and the detector are relatively moved by the width of the detector in synchronization with the stop time.

  According to the method disclosed in Patent Document 1, the operation of reciprocating the detector in a direction orthogonal to the inspection direction and the operation of relatively moving the metal surface and the detector in the inspection direction of the metal material are performed. By carrying out alternately, the vibration accompanying the running of the machine base on which the metal material is placed does not affect the inspection data, and inspection data with less noise can be obtained.

JP 60-133363 A

  According to the method disclosed in Patent Document 1, the detector repeats the following series of operations. First, the detector scans in a direction perpendicular to the feeding direction of the metal material while the machine base is stopped. After the detector finishes scanning, the detector stops. After the detector stops, the platform will run. After the machine has traveled a predetermined distance, the machine stops. Again, the detector scans in a direction perpendicular to the feeding direction of the metal material while the machine base is stopped.

  This series of operations cannot be applied when the metal material to be inspected is continuously fed. The present invention has been made to solve the above-described problem, and provides a defect inspection apparatus for a metal material capable of inspecting defects generated on the surface or inside of the metal material while continuously feeding the metal material. For the purpose.

  In order to detect a defect in the metal material, a defect inspection apparatus for a metal material according to the present invention is configured to place the metal material on the surface and continuously convey the metal material in the first direction. A detection head having a plurality of detectors arranged in a row so as to face the surface of the metal material, and supports the detection head above the metal material and is substantially orthogonal to the first direction. A support device that reciprocates the detection head in a second direction, and the support device is substantially orthogonal to the first posture, which is a direction parallel to the first direction, and the first posture. A rotation mechanism for rotatably supporting the detection head is included in the second posture.

  In another aspect of the invention, a position sensor that detects a distance between the surface of the metal material and the detector, and the detection head is moved in the vertical direction based on information obtained by the position sensor. And an elevating mechanism for controlling the detection head so that the distance is constant.

  In another aspect of the invention, the transport device is a roller that is disposed in front of and behind the first direction in which the metal material is transported and sandwiches the metal material from above and below in the detection head. .

  In the other form of the said invention, the encoder for detecting the rotation angle of the said roller is further provided.

  ADVANTAGE OF THE INVENTION According to this invention, the defect inspection apparatus of the metal material which can test | inspect the defect which arises on the surface and inside of a metal material can be provided, feeding a metal material continuously.

It is a perspective view which shows the structure of the defect inspection apparatus of the metal material in Embodiment 1, and shows the state by which the detection head was supported by the 1st attitude | position. It is a perspective view which shows the structure of the defect inspection apparatus of the metal material in Embodiment 1, and shows the state by which the detection head was supported by the 2nd attitude | position. In Embodiment 1, it is a top view which shows typically the locus | trajectory of a detector when the detection head is the state supported by the 1st attitude | position. In Embodiment 1, it is a top view which shows typically the locus | trajectory of a detector when the detection head is the state supported by the 2nd attitude | position. 6 is a perspective view showing a configuration of a metal material defect inspection apparatus according to Embodiment 2. FIG. FIG. 9 is a perspective view showing a configuration of a metal material defect inspection apparatus in a third embodiment.

  A metal material defect inspection apparatus according to each embodiment of the present invention will be described below with reference to the drawings. In each embodiment described below, when referring to the number, amount, and the like, the scope of the present invention is not necessarily limited to the number, amount, and the like unless otherwise specified. The same parts and corresponding parts are denoted by the same reference numerals, and redundant description may not be repeated.

(Embodiment 1)
(Configuration of defect inspection equipment for metal materials)
With reference to FIG. 1 and FIG. 2, the structure of the defect inspection apparatus of the metal material in this Embodiment is demonstrated. FIG. 1 shows a state in which the detection head 3 in the present embodiment is supported in the first posture P1. FIG. 2 shows a state in which the detection head 3 in the present embodiment is supported in the second posture P2. Details of the detection head 3, the first posture P1, and the second posture P2 will be described later.

  First, referring to FIG. 1, the defect inspection apparatus for a metal material in the present embodiment includes a transport apparatus 9, a detection head 3, and a support apparatus 8. The conveying device 9 places the metal material 1 on the surface. The transport device 9 continuously transports the metal material 1 in the first direction D1 (downward on the paper surface) with the metal material 1 placed on the surface. The first direction D <b> 1 according to the present embodiment corresponds to the longitudinal direction of the metal material 1. Hereinafter, the first direction D1 is referred to as a longitudinal direction.

  The detection head 3 has a plurality of detectors 2, 2 for detecting defects in the metal material 1. The detectors 2 and 2 can detect a defect of the metal material 1 on the lower surface. The detection head 3 arranges the detectors 2 and 2 in a row so that the surface of the metal material 1 faces the lower surfaces of the detectors 2 and 2. The detectors 2 and 2 may be arranged in one row, but may be two or more rows as long as they are in a row. In order to detect not only the surface of the metal material 1 but also the inside thereof, non-destructive inspection type detectors such as eddy current flaw detection (ET) or ultrasonic waves (UT) are used as the detectors 2 and 2.

  The support device 8 supports the detection head 3 above the metal material 1. Since the detection head 3 is supported, the detectors 2 and 2 can face the surface of the metal material 1 with a predetermined interval. The support device 8 reciprocates the detection head 3 in a second direction D2 that is substantially orthogonal to the longitudinal direction (first direction D1). The second direction D2 according to the present embodiment corresponds to the width direction of the metal material 1. Hereinafter, the second direction D2 is referred to as a width direction.

  The support device 8 supports the detection head 3 in a rotatable manner. The support device 8 supports the detection head 3 in the first posture P1 which is a direction parallel to the longitudinal direction (first direction D1). In addition, the support device 8 supports the detection head 3 in a second posture P2 (see FIG. 2) that is substantially orthogonal to the first posture P1. In the second posture P2, the detection head 3 is supported in parallel with the width direction (second direction D2) (see FIG. 2).

  With reference to FIG. 1 again, the configuration of the support device 8 will be described more specifically. The support device 8 includes a rotation mechanism 4, a beam 5, linear guides 6 and 6, and a support base 7.

  The rotation mechanism 4 has a central axis of rotation in a direction orthogonal to the metal material surface. The rotation mechanism 4 supports the detection head 3 to be rotatable. The rotation mechanism 4 rotates the detection head 3 on a plane parallel to the surface of the metal material 1. More specifically, the rotation mechanism 4 rotates the detectors 2 and 2 arranged in a row on a plane parallel to the surface of the metal material 1. The rotation mechanism 4 rotates the detection head 3 to the first posture P1 and the second posture P2. The rotation mechanism 4 may include a motor or the like as power for rotating the detection head 3.

  The beam 5 extends in a direction parallel to the longitudinal direction (first direction D1) of the metal material 1. The rotation mechanism 4 is supported on the side surface of the central portion of the beam 5.

  The linear guides 6 and 6 are provided side by side in a direction parallel to the width direction of the metal material 1 (second direction D2). The beam 5 is provided so as to form a bridge above the linear guides 6 and 6. The linear guides 6 and 6 support the beam 5 so as to be slidable. The linear guides 6 and 6 are provided side by side with a predetermined interval in the longitudinal direction. Since the linear guides 6 are provided side by side with a predetermined interval in the longitudinal direction, the detection head 3 can reciprocate in the width direction and can be rotated by a rotation mechanism.

  The support base 7 supports the linear guides 6 and 6 on the upper surface above the metal material 1 so as to straddle the metal material 1. By supporting the linear guides 6, 6 above the metal material 1 so that the support base 7 straddles the metal material 1, the lower surfaces of the detectors 2, 2, the detection head 3, the rotation mechanism 4, the beam 5, the linear It is possible to face the surface of the metal material 1 via the guides 6 and 6 with a predetermined interval.

(Operation: 1st posture)
The operation of the metal material defect inspection apparatus in the present embodiment will be described with reference to FIGS. First, a state where the detection head 3 is supported in the first posture P1 will be described with reference to FIGS. With reference to FIG. 1, when inspecting the entire surface of the metal material 1, the support device 8 is configured so that the direction in which the detectors 2 and 2 are aligned and the longitudinal direction of the metal material 1 are parallel to each other. Is supported in the first posture P1.

  At this time, the detection head 3 can inspect the entire surface of the metal material 1. Specifically, referring to FIG. 1 and FIG. 3, the width W (mm) of the metal material 1, the feed speed S (mm / s) of the metal material 1, and the longitudinal direction of the plurality of detectors 2 and 2 can be detected. When the length L (mm) is used, the speed Sp (mm / s) at which the detection head 3 reciprocates in the width direction satisfies the formula Sp = 2 × S × W / L.

  With reference to FIG. 3, when the entire surface of the metal material 1 is inspected, the locus group R <b> 1 of the detectors 2 and 2 is drawn. The trajectory group R1 is formed on the surface of the metal material 1 by the detection head 3 that reciprocates only in the width direction (second direction D2) with respect to the metal material 1 conveyed in the longitudinal direction (first direction D1). The locus to be drawn is schematically shown. At this time, the detection head 3 is supported in the first posture P1.

  In FIG. 3, for the sake of convenience of explanation, the detection head 3 including four detectors 2 and 2 is shown, but the number of detectors 2 and 2 is not limited to four. Although the trajectories of the detectors 2 and 2 are shown in a linear shape, actually, a trajectory having a predetermined width corresponding to the size of the detectors 2 and 2 is drawn. The width of the detection head 3 is represented as a detectable length L of the detectors 2 and 2. Moreover, although the case where the detection head 3 is reciprocatingly moved at a constant speed is shown, it actually reciprocates in a pattern such as acceleration / deceleration and S-shaped approximation.

  According to the above configuration, the support device 8 reciprocates at the speed Sp while supporting the detection head 3 in the first posture P1, so that the detectors 2 and 2 can move the entire surface of the metal material 1 over. Can be inspected. In particular, even when the width W is long or the number of detectors 2 and 2 to be arranged is small, according to the configuration as described above, the detection head 3 can inspect the entire surface of the metal material 1. Become.

  In other words, according to the configuration as described above, the number of detectors 2 and 2 to be arranged may be small. For example, the number of the detectors 2 and 2 is reduced so that the width W (mm) of the metal material 1 <the detectable length L (mm) of the detectors 2 and 2 in the longitudinal direction. Even in this case, the detection head 3 can inspect the entire surface of the metal material 1 by reciprocating the detection head 3 at the speed Sp. As a result, the facility scale can be reduced and the manufacturing cost can be reduced.

(Operation: 2nd posture)
Next, a state in which the detection head 3 is supported in the second posture P2 will be described with reference to FIGS. Referring to FIG. 2, when inspecting a partial region on the surface of the metal material 1, the support device 8 is arranged so that the alignment direction of the detectors 2 and 2 and the width direction of the metal material 1 are parallel to each other. Supports the detection head 3 in the second posture P2.

  At this time, with reference to FIGS. 2 and 4, when the width W (mm) of the metal material 1 and the detectable length L (mm) in the longitudinal direction of the plurality of detectors 2 and 2 are used, the detection head 3 May be reciprocated in the width direction by a distance W−L (mm).

  Referring to FIG. 4, when a partial region on the surface of the metal material 1 is inspected, a locus group R2 of the detectors 2 and 2 is drawn. This locus group R2 is formed on the surface of the metal material 1 by the detection head 3 that reciprocates only in the width direction (second direction D2) with respect to the metal material 1 conveyed in the longitudinal direction (first direction D1). The locus to be drawn is schematically shown. At this time, the detection head 3 is supported in the second posture P2.

  As in FIG. 3, in FIG. 4, the locus of the detectors 2 and 2 is linearly illustrated for convenience of explanation, but actually has a predetermined width corresponding to the size of the detectors 2 and 2. A trajectory is drawn. The width of the detection head 3 is represented as a detectable length L of the detectors 2 and 2. Moreover, although the case where the detection head 3 is reciprocatingly moved at a constant speed is shown, it actually reciprocates in a pattern such as acceleration / deceleration and S-shaped approximation.

  According to the second posture P2, the distance that the detection head 3 reciprocates is shorter than that in the first posture P1. More specifically, the distance required for the reciprocating movement of the detection head 3 is W− (W−L) = L (mm), that is, the length of the detection head 3 in the case of one-way as compared with the case of detecting the entire area. Only a short distance will be required. Therefore, according to the 2nd attitude | position P2, when test | inspecting the partial area | region of the surface of the metal material 1, it becomes possible to test | inspect in a shorter time compared with the 1st attitude | position P1.

  Referring to FIG. 4 again, when a more limited area on the surface of the metal material 1 is to be inspected, the detector 2, 2 is supported with the support device 8 supporting the detection head 3 in the second posture P2. Of these, only a part of the detectors 2 (2A) may be used (so-called thinning-out use). By using only some of the detectors 2A, it is possible to shorten the time required for detecting a defect in the partial inspection and specifying the position of the defect.

  This thinning use may be applied in a state where the support device 8 supports the detection head 3 in the first posture P1. Specifically, referring to FIG. 3 again, when a partial region on the surface of the metal material 1 is inspected, the detection is performed with the support device 8 supporting the detection head 3 in the first posture P1. Only some of the detectors 2 and 2 (2A) need be used. By using only some of the detectors 2A, it is possible to shorten the time required for detecting a defect in the partial inspection and specifying the position of the defect.

(effect)
According to the defect inspection apparatus for a metal material according to the present embodiment, the transport device 9 continuously transports the metal material 1 in the longitudinal direction (first direction D1). The support device 8 reciprocates the detection head 3 in the width direction (second direction D2) without synchronizing with the continuous movement of the metal material 1. For this reason, it is possible to inspect defects generated on the surface or inside of the metal material 1 while continuously feeding the metal material 1.

  Further, according to the defect inspection apparatus for metal material according to the present embodiment, the support device 8 supports the detection head 3 rotatably in the first posture P1 and the second posture P2. For this reason, these can be freely selected according to the purpose, and the entire surface of the metal material 1 can be inspected or a partial region can be inspected.

  The support device 8 has been described as supporting the detection head 3 in the first posture P1 and the second posture P2, but the detection head 3 may be supported in a posture other than these. In the first posture P1, the range in which the detectors 2 and 2 can detect the surface of the metal material 1 is the widest, and the entire surface of the metal material 1 can also be detected. In the second posture P2, the range in which the detectors 2 and 2 can detect the surface of the metal material 1 is the smallest. Therefore, the support device 8 may support the detection head 3 in an arbitrary posture between the first posture P1 and the second posture P2 according to a desired detection range.

(Embodiment 2)
With reference to FIG. 5, the structure of the defect inspection apparatus of the metal material in this Embodiment is demonstrated. The metal material defect inspection apparatus in the present embodiment further includes a position sensor 11 and an elevating mechanism 10 in addition to the configuration of the first embodiment.

  The position sensor 11 detects the distance between the surface of the metal material 1 and the detectors 2 and 2. The position sensor 11 is preferably embedded in the detection head 3. The lifting mechanism 10 moves the detection head 3 in the vertical direction D3 based on the information obtained by the position sensor 11. At this time, the detection head 3 may be attached to the beam 5 via the lifting mechanism 10. The elevating mechanism 10 controls the height of the detection head 3 so that the distance between the surface of the metal material 1 and the detectors 2 and 2 is constant.

  As described above, the operation of reciprocating the detector in a direction orthogonal to the feeding direction (inspection direction) of the metal material and the operation of moving the metal surface and the detector relatively in the feeding direction (inspection direction) of the metal material Are alternately performed, vibration associated with the running of the machine base on which the metal material is placed does not affect the inspection data, and inspection data with less noise can be obtained (Patent Document 1). . According to this inspection method, since the machine base does not travel when the detector reciprocates, it is possible to detect defects with little influence of noise. However, the effect on the noise generated by the scanning of the detector itself remains.

  According to the defect inspection apparatus for metal material in the present embodiment, the lifting mechanism 10 is driven according to the detection value of the position sensor 11 so that the clearance (clearance) between the detector 2 and the metal material 1 is kept constant. . For this reason, when the detection head 3 reciprocates, noise due to vibration received from the linear guide 6 can be suppressed. As a result, it is possible to inspect defects generated on the surface and inside of the metal material with higher accuracy.

(Embodiment 3)
With reference to FIG. 6, the structure of the defect inspection apparatus of the metal material in this Embodiment is demonstrated. The metal material defect inspection apparatus according to the present embodiment is different from the first embodiment or the second embodiment in the transport device 9. The transport device 9 according to the present embodiment is rollers 12 and 12.

  The rollers 12 and 12 are preferably arranged in front of and behind the detection head 3 in the longitudinal direction (first direction D1) in which the metal material 1 is conveyed. The rollers 12 and 12 convey the metal material continuously in the first direction D1 while sandwiching the metal material 1 from the vertical direction D3.

  The rollers 12 and 12 restrain the movement of the metal material 1 in the height direction by sandwiching the metal material 1 from the vertical direction D3. For this reason, when the metal material 1 is conveyed, it is possible to press noise caused by vibrations received from the conveying device 9 (rollers 12 and 12). As a result, it is possible to inspect defects generated on the surface and inside of the metal material with higher accuracy.

  In particular, by applying the rollers 12 and 12 to the transport device 9 according to the second embodiment, noise due to vibration received from the linear guide 6 when the detection head 3 reciprocates by the position sensor 11 can be suppressed. Not only can it be possible, but also noise caused by vibrations received from the transport device 9 (rollers 12, 12) can be pushed. As a result, it is possible to inspect defects generated on the surface and inside of the metal material with higher accuracy.

(Other configuration of the third embodiment)
Referring to FIG. 6 again, the configuration of the metal material defect inspection apparatus in the present embodiment will be described. In addition to the configuration of the third embodiment, the metal material defect inspection apparatus in the present embodiment further includes an encoder 13 for detecting the rotation angles of the rollers 12 and 12.

  The encoder 13 may be an optical position detection sensor installed on a rotating shaft used for a servo motor. The encoder 13 detects the rotation position (or rotation amount) of the rollers 12 and 12.

  Consider the case where the encoder 13 is not provided. For example, according to the configuration of each of the above embodiments, the defect position information is calculated from the presence / absence of a defect, the feed speed of the detection head 3 or the metal material 1, the time when the defect is found, and the like. The position can be specified. In this case, the position information of the defect can be calculated as relative position information based on the elapsed time and the feed speed from the position where the detection is started, and the actual position of the defect can be specified.

  On the other hand, by using the encoder 13 as in the present embodiment, the defect presence / absence information detected by the detectors 2 and 2 and the defect position information calculated from the rotation positions of the rollers 12 and 12 are combined. The position of the actual defect can be specified. By using the encoder 13, it is possible to specify the position of the defect more quickly and with higher accuracy than the configuration of each of the above embodiments.

  Although the embodiments of the present invention have been described above, the embodiments disclosed this time should be considered as illustrative in all points and not restrictive. The scope of the present invention is defined by the terms of the claims, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

  DESCRIPTION OF SYMBOLS 1 Metal material, 2, 2A detector, 3 detection head, 4 rotation mechanism, 5 beam, 6 linear guide, 7 support stand, 8 support apparatus, 9 conveyance apparatus, 10 raising / lowering mechanism, 11 position sensor, 12 roller, 13 encoder , D1 longitudinal direction (first direction), D2 width direction (second direction), D3 vertical direction, P1 first posture, P2 second posture, R1, R2 trajectory group, S, Sp speed, W width .

Claims (4)

A transport device that places the metal material on the surface and continuously transports the metal material in the first direction;
In order to detect a defect in the metal material, a detection head having a plurality of detectors arranged in a row so as to face the surface of the metal material;
A support device for supporting the detection head above the metal material and reciprocating the detection head in a second direction substantially orthogonal to the first direction;
With
The support device includes a rotation mechanism that rotatably supports the detection head in a first posture that is parallel to the first direction and a second posture that is substantially orthogonal to the first posture. ,
Metal material defect inspection equipment. A position sensor for detecting a distance between the surface of the metal material and the detector;
Based on information obtained by the position sensor, the elevating mechanism that moves the detection head in the vertical direction and controls the detection head so that the distance becomes constant;
The metal material defect inspection apparatus according to claim 1, further comprising: The transport device is a roller that is disposed in front and rear in the first direction in which the metal material is transported of the detection head and sandwiches the metal material from above and below.
The defect inspection apparatus for a metal material according to claim 1 or 2. An encoder for detecting a rotation angle of the roller;
The metal material defect inspection apparatus according to claim 3.

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