JP2008241612A - Defect inspection device and method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a defect inspection device and method to quickly and accurately perform a defect inspection even when inspecting inspection faces of both upper and lower sides of an inspection object. <P>SOLUTION: The defect inspection device 1 includes a support plate 3 on which the inspection object 2 is placed, conveyance units 4A, 4B which convey the inspection object 2 placed on the support plate 3, and two-dimensional laser displacement meters 5A, 5B which are arranged above and below the support plate 3 and measure the distances to both the inspection faces of the inspection object 2 by radiating a laser beam on the inspection faces of both the upper and lower sides of the inspection object 2 and receiving the reflected light from each inspection face. An opening 6 for inspection is provided for transmitting the laser beam from the two-dimensional laser displacement meter 5B at the central part of the support plate 3. When the inspection object 2 is conveyed to the opening 6 for inspection (inspection region X), the distances to both the inspection faces of the inspection object 2 are simultaneously measured with the two-dimensional laser displacement meters 5A, 5B. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a defect inspection apparatus and method for inspecting a surface state defect of an inspection object.

As a method for inspecting a surface state defect of an inspection object, for example, as described in Patent Document 1, a laser beam is projected onto the inspection object, and reflected light from the inspection object is received. One using a two-dimensional laser rangefinder that measures the distance to an object is known.
JP-A-6-74711

  However, the following problems exist in the prior art. That is, for example, when the inspection object is a plate-like body and the upper and lower surfaces of the plate-like body are inspected, an operation of flipping the plate-like body up and down is required. For this reason, a considerable time is required for defect inspection of one plate-like body. Further, when the plate-like body is turned upside down, the position and posture of the plate-like body may be shifted, and in this case, erroneous detection of a defect occurs. Furthermore, in order to reverse the plate-like body upside down, an operation for changing the plate-like body is required, so that the reversing mechanism becomes very complicated.

  An object of the present invention is to provide a defect inspection apparatus and method capable of performing defect inspection quickly and accurately even when inspecting inspection surfaces on both upper and lower sides of an inspection object.

  The present invention is a defect inspection apparatus for continuously inspecting a surface state defect of a plurality of inspection objects, a support member on which the inspection object is placed, and an inspection placed on the support member Reflected from each inspection surface by irradiating the inspection surface on both the upper and lower sides of the inspection object with laser light, arranged vertically so as to oppose the conveying means that conveys the object to the inspection area of the support member Based on the measurement results of a pair of two-dimensional laser displacement meters that measure the distance to each inspection surface by receiving light and a pair of two-dimensional laser displacement meters, surface condition defects of the inspection object And a defect detection means for detecting.

  When such a defect inspection apparatus is used to inspect defects in the surface state of the inspection object, the inspection object is placed in the inspection area of the support member by the conveying means while the inspection object is placed on the support member. Transport toward. When the inspection object reaches the inspection region, the distances to the inspection surfaces on both the upper and lower sides of the inspection object are simultaneously measured by a pair of two-dimensional laser displacement meters. Thus, since the distance to each inspection surface of the inspection object is not measured one side at a time, but is measured simultaneously, the operation of inverting the inspection object one by one up and down becomes unnecessary. Thereby, the time required for the defect inspection of the surface state of the inspection object can be shortened. In addition, by measuring the distance to each inspection surface of the inspection object at the same time, the positional / posture relationship of each inspection surface of the inspection object is measured in a constant state. It is possible to prevent erroneous detection of defects due to a shift in the position / posture relationship of the surfaces.

  Preferably, the support member has an inspection opening forming an inspection region, and an opening width narrower than a width dimension of the inspection object is provided on both left and right sides of the inspection opening along the conveyance direction of the inspection object. Each of the slits is provided.

  In this case, the distance to the upper inspection surface of the inspection object by the upper two-dimensional laser displacement meter in a state where both ends of the inspection object are placed on the left and right side portions of the inspection opening in the support member. Is measured, and the distance to the lower inspection surface of the inspection object is measured through the inspection opening by the lower two-dimensional laser displacement meter. At this time, if the length from the end of one slit to the end of the other slit is equal to or greater than the length of the object to be inspected, the bottom two By passing the laser beam from the three-dimensional laser displacement meter, it becomes possible to apply the laser beam to the entire inspection surface on the lower side of the inspection object, so that the accuracy of defect detection can be further improved. Further, since the opening width of the slit is narrower than the width dimension of the inspection object, the inspection object is not dropped from the slit when the inspection object is conveyed by the conveying means. In addition, it is preferable that the opening width of a slit is narrower than half of the width dimension of a test object. As a result, when the inspection object passes over the inspection opening (inspection region) by the conveying means, the inspection object extends along the conveyance direction in the left and right side portions of the inspection opening. Since it is in a state where it is always in contact with the support member at half or more of the dimension, it is possible to reliably suppress the slit from inclining the inspection object.

  Further, the support member has a pair, and the pair of support members are arranged so as to extend in parallel to each other, and each support member has an opening width narrower than the width dimension of the inspection object. Each of the slits forming the inspection area may be provided.

  In this case, the distance from the upper two-dimensional laser displacement meter to the upper inspection surface of the inspection object is set in a state where both ends of the inspection object are placed on each support member arranged at an arbitrary interval. The distance to the lower inspection surface of the inspection object is measured by the lower two-dimensional laser displacement meter. At this time, if the length from the end of one slit to the end of the other slit is equal to or longer than the length dimension of the inspection object, the lower two-dimensional laser displacement meter By passing the laser beam, it becomes possible to apply the laser beam to the entire inspection surface on the lower side of the inspection object, so that the accuracy of defect detection can be further improved. Further, since the opening width of the slit is narrower than the width dimension of the inspection object, the inspection object is not dropped from the slit when the inspection object is conveyed by the conveying means. In addition, it is preferable that the opening width of a slit is narrower than half of the width dimension of a test object. Thereby, when the inspection object passes over the inspection region by the conveying means, the inspection object is always in contact with each support member at a half or more of the width dimension of the inspection object along the conveyance direction; Therefore, it is possible to reliably suppress the slit from inclining the inspection object.

  At this time, it is preferable to further include an interval adjusting means for adjusting the distance between the pair of support members. In this case, by adjusting the distance between the pair of support members according to the length dimension of the inspection object, even if the length dimension of the inspection object changes, the both ends of the inspection object can be surely attached. Defect inspection can be performed by mounting on each support member.

  In addition, a defect inspection method for continuously inspecting defects in a surface state of a plurality of inspection objects, the support member on which the inspection objects are placed facing each other across an inspection region of the support member A pair of two-dimensional lasers that are arranged vertically and measure the distance to each inspection surface by irradiating the inspection surface on both the upper and lower sides of the inspection object with laser light and receiving the reflected light from each inspection surface A step of preparing the displacement meter, a step of placing the inspection object on the support member, and transporting the inspection object to the inspection area in that state, and a pair of the inspection object when the inspection object reaches the inspection area. The surface state defect of the inspection object is detected based on the process of simultaneously measuring the distance to each inspection surface of the inspection object using the two-dimensional laser displacement meter and the measurement result of the pair of two-dimensional laser displacement meters. And a process.

  Using such a pair of two-dimensional laser displacement meters arranged above and below, the distance to the inspection surface on both the upper and lower sides of the inspection object is simultaneously measured, so that there is no need to invert the inspection object one by one. It becomes. Thereby, the time required for the defect inspection of the surface state of the inspection object can be shortened. In addition, it is possible to prevent erroneous detection of defects due to a shift in the position / posture relationship between the inspection surfaces of the inspection object.

  According to the present invention, even when inspecting inspection surfaces on both upper and lower sides of an inspection object, defect inspection can be performed quickly and accurately. This is effective when performing defect inspection of a large number of inspection objects continuously.

  DESCRIPTION OF EMBODIMENTS Hereinafter, preferred embodiments of a defect inspection apparatus and method according to the present invention will be described in detail with reference to the drawings.

  FIG. 1 is an overall configuration diagram (including a partial cross-section) showing a first embodiment of a defect inspection apparatus according to the present invention. 2 is a plan view of the main part of the defect inspection apparatus shown in FIG. 1, and FIG. 3 is a cross-sectional view of the main part of the defect inspection apparatus shown in FIG. In each figure, the defect inspection apparatus 1 of this embodiment is an apparatus for continuously inspecting surface state defects of a large number of inspection objects 2.

  As shown in FIG. 4, the inspection object 2 is a curved plate-shaped small magnet, and is used for a motor, for example. The inspection object 2 has an outer curved surface 2a, an inner curved surface 2b, two side surfaces 2c, and two end surfaces 2d. In the process of manufacturing such an inspection object 2, the outer curved surface 2a and the inner curved surface 2b are polished. The defect inspection apparatus 1 inspects defects generated on the outer curved surface 2a and the inner curved surface 2b due to poor polishing or the like.

  The defect inspection apparatus 1 includes a rectangular support plate 3 on which an inspection object 2 is placed and an inspection object 2 placed on the left and right sides of the support plate 3 and placed on the support plate 3 with an arrow A. The distances (displacements) to the inspection surfaces on the upper and lower sides of the inspection object 2 are respectively measured using the two-dimensional laser light, which are arranged above and below the conveyance units 4A and 4B that convey in the direction and the support plate 3. Two-dimensional laser displacement meters 5A and 5B are provided.

  The support plate 3 is attached to the upper end of a leg (not shown). In the central part of the support plate 3, an inspection opening 6 is provided for transmitting the laser light from the two-dimensional laser displacement meter 5 </ b> B disposed below the support plate 3. The inspection opening 6 forms an inspection region X for inspecting the inspection object 2.

The inspection opening 6 has a rectangular opening window 7 and a pair of slits 8 formed on the left and right sides of the opening window 7. The opening width W ₁ of the opening window 7 is larger than, for example, the width dimension D of the inspection object 2, and the opening width W ₂ of the slit 8 is sufficiently smaller than the width dimension D of the inspection object 2. Yes. A chamfer 9 is formed at the edge of the inspection opening 6 including the slit 8 on the downstream side of the conveyance.

The inspection object 2 is placed on the support plate 3 such that both end surfaces 2d straddle the opening window 7 with respect to the width direction (left-right direction) of the support plate 3 with the outer curved surface 2a facing upward. The At this time, as the displacement of the inspection object 2 of the inner curved surface 2b and the end surfaces 2d by the laser light is measurable over the entire surface of the two-dimensional laser displacement gauge 5B, inspection including the opening width W ₂ of the slit 8 The dimensions of the opening 6 are defined.

  The transport units 4A and 4B include a driving roller 10 and a driven roller 11 disposed in the vicinity of both ends of the support plate 3, respectively, a profile belt 12 stretched between the driving roller 10 and the driven roller 11, and a driving roller 10 And a motor 13 that rotates the motor. The driven roller 11 is held by a roller holding member 14 so as to be freely rotatable. A plurality of conveying frames 15 are attached to the profile belt 12 at equal intervals.

  When the motors 13 of the transport units 4A and 4B are rotated at the same speed in opposite directions (B direction in FIG. 2) in a state where the transport frames 15 of the transport units 4A and 4B are in positions corresponding to each other, The profile belts 12 of the units 4A and 4B move in synchronization. For this reason, both end portions of the inspection object 2 placed on the support plate 3 are pushed by the pair of conveying pieces 15 so that the inspection object 2 slides on the support plate 3.

At this time, in the inspection region of the support plate 3, both end portions of the inspection object 2 pass over the slit 8, but the opening width W ₂ of the slit 8 is the width dimension of the inspection object ₂ as described above. Since it is sufficiently narrower than D, the inspection object 2 does not fall off at the position of the slit 8. Further, on the opening width W ₂ of the slit 8 is sufficiently narrow, since the edge portion of the conveyance downstream side of the inspection opening 6 chamfer 9 is provided, the inspection object 2 inspection openings 6 The inspection object 2 is smoothly transported on the support plate 3.

  The means for transporting the inspection object 2 placed on the support plate 3 is not limited to the transport units 4A and 4B described above. For example, the inspection object 2 is pressed and transported only at the beginning. Also good.

  The two-dimensional laser displacement meters 5A and 5B are arranged so as to face each other with an inspection opening 6 formed in the support plate 3 interposed therebetween. The two-dimensional laser displacement meters 5A and 5B include a light projecting unit 16 that irradiates the inspection target 2 with laser light, and a light receiving unit 17 that receives the laser light (reflected light) reflected by the inspection target 2. The distance to the inspection object 2 is measured using the principle of two-dimensional triangulation.

  The light projecting unit 16 includes, for example, a laser diode that generates laser light and a cylindrical lens that spreads the laser light emitted from the laser diode in a band shape (line shape). The light receiving unit 17 includes, for example, a CMOS image sensor or a CCD that forms an image by capturing the reflected light from the inspection object 2.

  The light projecting unit 16 of the two-dimensional laser displacement meter 5A is disposed immediately above the position corresponding to the slit 8 of the inspection opening 6, and the light projecting unit 16 of the two-dimensional laser displacement meter 5B corresponds to the slit 8. It is arranged directly under the position. Each light projecting unit 16 irradiates a line-shaped laser beam toward a portion including each slit 8 of the inspection opening 6. The light receiving unit 17 of the two-dimensional laser displacement meter 5A is inclined to the downstream side of the light projecting unit 16 and the light receiving unit 17 of the two-dimensional laser displacement meter 5B is on the upstream side of the light projecting unit 16. It is arranged at an angle.

  Here, the line-shaped laser light emitted from the light projecting unit 16 of the two-dimensional laser displacement meter 5A hits the entire surface of the outer curved surface 2a for one line of the inspection object 2, and is reflected by the outer curved surface 2a. The laser light is taken into the light receiving unit 17 so that measurement data for each line is sequentially obtained. Also, the line-shaped laser light emitted from the light projecting portion 16 of the two-dimensional laser displacement meter 5B passes through the inspection opening 6 and the entire inner curved surface 2b and both end surfaces 2d of the inspection object 2 for one line. In this case, the laser light reflected by the inner curved surface 2b and the both end surfaces 2d is taken into the light receiving unit 17 through the inspection opening 6, whereby measurement data for each line is sequentially obtained.

  The two-dimensional laser displacement meters 5A and 5B are connected to the displacement meter controller 18. The displacement meter controller 18 is connected to a personal computer 19. The displacement meter controller 18 controls the light projecting unit 16 of the two-dimensional laser displacement meters 5A and 5B and performs predetermined processing based on the measurement data from the light receiving unit 17 of the two-dimensional laser displacement meters 5A and 5B. The result is output to the personal computer 19.

  FIG. 5 is a flowchart showing a processing procedure executed by the displacement meter controller 18. In the figure, first, a measurement signal from the light receiving unit 17 of the two-dimensional laser displacement meters 5A and 5B is input (step S101).

  And based on the measurement signal from each light-receiving part 17, the profile data which profiled the surface of the inspection target object 2 for 1 line are each produced (procedure S102). 6A shows an example of profile data of the upper inspection surface (outer curved surface 2a) of the inspection object 2, and FIG. 6B shows the lower inspection surface of the inspection object 2 ( An example of profile data of the inner curved surface 2b and both end surfaces 2d) is shown.

Subsequently, the thickness dimension of the inspection object 2 for one line is obtained (procedure S103). Specifically, the distance a between the two-dimensional laser displacement meters 5A and 5B is stored in advance in the memory. Further, based on the profile data of the upper inspection surface obtained in step S102, the distance b from the two-dimensional laser displacement meter 5A to the upper inspection surface of the inspection object 2 is obtained for one line, and is obtained in step S102. On the basis of the profile data of the lower inspection surface, the distance c from the two-dimensional laser displacement meter 5B to the lower inspection surface is obtained for one line. Then, the thickness dimension t of the inspection object 2 is obtained from the following formula.
t = a- (b + c)

  Thus, by measuring the distance to the upper inspection surface and the lower inspection surface of the inspection object 2 at the same time, the thickness dimension of the inspection object 2 can be adjusted without taking into consideration the influence of the height and thickness of the support plate 3. It can be easily obtained.

  Then, data of the thickness dimension t of the inspection object 2 is output to the personal computer 19 (step S104). Hereinafter, the thickness dimension t for each line of the inspection object 2 is obtained by repeatedly performing the above steps S101 to S104.

  Based on the thickness data of the inspection object 2 sent from the displacement meter controller 18, the personal computer 19 analyzes whether the surface of the inspection object 2 has defects such as poor polishing or chipping. As an analysis method, for example, master data of the thickness dimension of the inspection object 2 may be prepared in advance, and the actual thickness dimension of the inspection object 2 may be compared with the master data. You may determine the symmetry of thickness data.

  Thus, since the displacement meter controller 18 sends only the thickness dimension data for each line of the inspection object 2 to the personal computer 19, the amount of data sent from the displacement meter controller 18 to the personal computer 19 can be reduced, and the defect analysis processing by the personal computer 19 is possible. Can be simplified.

  Returning to FIG. 1 and FIG. 2, the defect inspection apparatus 1 further includes a carry-in conveyor 20 installed on the conveyance upstream side of the support plate 3 and a carry-out conveyor 21 installed on the conveyance downstream side of the support plate 3. . Between the support plate 3 and the carry-in conveyor 20, a transfer hand 22 for sequentially transferring the inspection object 2 from the carry-in conveyor 20 to the support plate 3 is disposed. The transfer hand 22 is provided with a plurality of suction pads 23 for sucking and holding the inspection object 2. The transfer hand 22 rotates by the actuator 24 and moves up and down.

  The carry-out conveyor 21 is arranged close to the support plate 3. Thereby, delivery of the test object 2 from the support plate 3 to the carry-out conveyor 21 can be easily performed.

  Next, a method for inspecting a surface state defect of the inspection object 2 using the defect inspection apparatus 1 configured as described above will be described.

  First, the drive rollers 10 are rotationally driven in opposite directions by the motors 13 of the two-dimensional laser displacement meters 5A and 5B, so that the pair of profile belts 12 are in opposite directions (in the direction of arrow B in FIG. 2). Synchronize and move at the same speed.

  Then, the transfer hand 22 is lowered, the inspection object 2 conveyed on the carry-in conveyor 20 is sucked and held by the suction pad 23, and in this state, the transfer hand 22 is lifted, rotated and lowered sequentially. The suction of the inspection object 2 by the suction pad 23 is released, and the inspection object 2 is placed on the support plate 3. Then, since the conveyance piece 15 attached to each profile belt 12 being driven continues to push the inspection object 2, the inspection object 2 slides on the support plate 3 in the direction of arrow A.

  When the inspection object 2 reaches the inspection opening 6 (inspection region X), the laser light emitted from the light projecting section 16 of the two-dimensional laser displacement meters 5A and 5B is reflected on the upper inspection surface of the inspection object 2 and By being reflected by the lower inspection surface and entering the light receiving unit 17, the distance to both inspection surfaces of the inspection object 2 is measured simultaneously.

  Measurement data obtained by the two-dimensional laser displacement meters 5A and 5B are sequentially sent to the displacement meter controller 18, and the displacement meter controller 18 determines the thickness dimension of the inspection object 2. Then, the thickness data of the inspection object 2 is sequentially sent to the personal computer 19, and the personal computer 19 analyzes whether or not there is a defect on the surface of the inspection object 2.

  The inspection object 2 that has been measured by the two-dimensional laser displacement meters 5A and 5B is further slid on the support plate 3 and transferred to the carry-out conveyor 21. Thereafter, the inspection object 2 having no defect is sent as a non-defective product to an alignment conveyor (not shown), and the inspection object 2 having a defect is separately discharged as a defective product. Thereafter, the above-described steps are continuously performed for the quantity of the inspection object 2 to be inspected.

  As described above, in the present embodiment, the two-dimensional laser displacement meters 5A and 5B are respectively disposed above and below the support plate 3 having the inspection opening 6, and these two-dimensional laser displacement meters 5A and 5B. Thus, since the distances to the upper inspection surface and the lower inspection surface of the inspection object 2 are measured at the same time, the inspection object 2 does not have to be turned over in order to perform measurement on both inspection surfaces of the inspection object 2. For this reason, the time required for the inspection of one inspection object 2 is greatly shortened. In addition, since a mechanism for changing or reversing the inspection object 2 is not required, the structure of the apparatus is simplified.

  Further, when the inspection object 2 is turned upside down from the state in which the outer curved surface 2a faces upward to the state in which the inner curved surface 2b faces upward, the position and posture of the inspection object 2 are shifted before and after the reversing operation. There is. In this case, since an accurate thickness dimension of the inspection object 2 cannot be obtained, erroneous detection of a defect may occur. Further, it is conceivable to detect a defect present on the surface of the inspection object 2 by image processing. However, in this case, since the image is shaded on the outer curved surface 2a and the inner curved surface 2b of the inspection object 2, it is difficult to detect a defect.

  In this embodiment, since the measurement on the upper inspection surface and the lower inspection surface of the inspection object 2 is simultaneously performed by the two-dimensional laser displacement meters 5A and 5B, the position and orientation of the inspection object 2 are determined when the inspection object 2 is transported. Even if the support plate 3 is slightly displaced, the positional / posture relationship between the upper inspection surface and the lower inspection surface of the inspection object 2 does not change. For this reason, since the exact thickness dimension of the test object 2 is obtained, the erroneous detection of a defect can be prevented.

  In this way, it is possible to inspect in a short time and with high accuracy whether there is a defect on the surface of the inspection object 2. As a result, it is possible to sufficiently cope with the demand for continuously inspecting the surface state defects of a large number of small parts at high speed.

  FIG. 7 is an overall configuration diagram (including a partial cross section) showing a second embodiment of the defect inspection apparatus according to the present invention. 8 is a plan view of the defect inspection apparatus shown in FIG. 7, and FIG. 9 is a cross-sectional view of the defect inspection apparatus shown in FIG. In the figure, the same or equivalent members as those in the first embodiment are denoted by the same reference numerals, and the description thereof is omitted.

In each figure, the defect inspection apparatus 30 of this embodiment is provided with a pair of belt-like support plates 31 arranged so as to extend in parallel to each other, instead of the support plate 3 in the first embodiment. A wall plate 32 extending along the support plate 31 is fixed to the outer side surface of each support plate 31. A slit 33 that forms an inspection region X for inspecting the inspection object 2 is formed at the center of each support plate 31. The opening width W of the slit 33 ₂ is equal to the opening width of the slit 8 formed in the support plate 3 in the first embodiment. A chamfer 34 is formed at the edge of the slit 33 on the downstream side of conveyance.

  The inspection object 2 is placed on each support plate 31 so that both end surfaces 2d straddle the space between the support plates 31 with the outer curved surface 2a facing upward. At this time, since the wall plate 32 is provided on the outer side of each support plate 31, the inspection object 2 is prevented from falling off.

  Further, the defect inspection apparatus 30 includes an interval adjustment unit 35 that adjusts an interval (distance) between the support plates 31, and conveyance units 36 </ b> A and 36 </ b> B that convey the inspection object 2 placed on the support plates 31. The two-dimensional laser displacement meters 5A and 5B are disposed above and below the support plate 31, respectively.

  The interval adjusting unit 35 has a pair of screw nuts 37 fixed to the lower surface of each support plate 31, and a screw shaft 38 extending in the width direction of the support plate 31 passes through these screw nuts 37. The screw shaft 38 has male screw portions 39 a and 39 b that are threaded in directions opposite to each other, and the male screw portions 39 a and 39 b are respectively screwed into female screws formed on the screw nuts 37. A rotation handle 40 is attached to one end of the screw shaft 38.

  Sliders 41 are respectively attached to the lower surface of one end portion of each support plate 31, and these sliders 41 are slidable on slide rails 42 extending in the width direction of the support plate 31. Further, sliders 43 are respectively attached to the lower surfaces of the other end portions of the respective support plates 31, and these sliders 43 are slidable on slide rails 44 extending in the width direction of the support plate 31. The slide rails 42 and 44 are fixed to the upper end of the leg portion 45. The screw shaft 38 is connected to both ends of the slide rail 42 via a pair of connecting plates 46. A bearing 47 is provided between the screw shaft 38 and the connecting plate 46.

  In such an interval adjusting unit 35, when the rotation handle 40 is rotated, the screw shaft 38 rotates, so that the screw nuts 37 engaged with the screw shaft 38 move in a direction approaching or separating from each other. Each slider 41 slides on the slide rail 42 and each slider 43 slides on the slide rail 44. As a result, the pair of support plates 31 move in a direction approaching or separating from each other, and the interval between the support plates 31 changes. Thereby, even if the dimension of the inspection object 2 changes, the both end surfaces 2d of the inspection object 2 can be easily placed on each support plate 31.

  The transport units 36 </ b> A and 36 </ b> B have an L-shaped roller holding plate 48 fixed to one end of the wall plate 32 and an L-shaped roller holding plate 49 fixed to the other end of the wall plate 32. . A driving roller 50 and a driven roller 51 are supported on the roller holding plate 48 so as to be rotatable up and down, and two driven rollers 52 are supported on the roller holding plate 49 so as to be rotatable up and down. A profile belt 53 is stretched around the driving roller 50, the driven roller 51, and each driven roller 52. A plurality of conveyance pieces 54 are attached to the profile belt 53 at equal intervals. The drive roller 50 is rotationally driven by a motor 55.

  When the motors 55 of the transport units 36A and 36B are rotated at the same speed in the same direction while the transport frames 54 of the transport units 36A and 36B are in positions corresponding to each other, the pair of profile belts 53 are synchronized. It moves. For this reason, both ends of the inspection object 2 placed on the pair of support plates 31 are pushed by the transport piece 54, and the inspection object 3 slides on the support plates 31.

  The two-dimensional laser displacement meters 5A and 5B are arranged so as to face each other with a slit 33 (inspection region X) formed in each support plate 31 interposed therebetween. The light projecting unit 16 of the two-dimensional laser displacement meter 5A is disposed immediately above the position corresponding to the slit 33, and the light projecting unit 16 of the two-dimensional laser displacement meter 5B is disposed immediately below the position corresponding to the slit 33. Yes. Each light projecting unit 16 irradiates a line-shaped laser beam toward a portion including each slit 33.

  In the present embodiment as described above, the two-dimensional laser displacement meters 5A and 5B are respectively disposed above and below the pair of support plates 31 having the slits 33, and inspection is performed by these two-dimensional laser displacement meters 5A and 5B. Since the distance to the upper inspection surface and the lower inspection surface of the object 2 is measured simultaneously, it is not necessary to invert the inspection object 2 one by one. Thereby, similarly to 1st Embodiment, it can test | inspect in a short time and with high precision whether the surface of the test object 2 has a defect.

  The present invention is not limited to the above embodiment. For example, in the first embodiment, the inspection object 2 is placed on the support plate 3 having the inspection opening 6, but a transparent plate that transmits laser light may be incorporated in the inspection opening 6. Alternatively, the support plate 3 itself may be formed of a transparent plate.

  Moreover, although the said embodiment inspects the defect of the surface state of the curved plate-shaped magnet, this invention is also used for the defect inspection of other kinds of small parts, such as a flat plate shape or a semi-columnar magnet. Applicable.

1 is an overall configuration diagram (including a partial cross section) illustrating a first embodiment of a defect inspection apparatus according to the present invention. It is a top view of the defect inspection apparatus shown in FIG. It is sectional drawing of the defect inspection apparatus shown in FIG. It is a perspective view which shows an example of the test target object test | inspected by the defect inspection apparatus shown in FIGS. It is a flowchart which shows the process sequence performed by the displacement meter controller shown in FIG. It is a graph which shows an example of profile data of both inspection surfaces of an inspection subject. It is a whole block diagram (a partial cross section is included) which shows 2nd Embodiment of the defect inspection apparatus which concerns on this invention. It is a top view of the defect inspection apparatus shown in FIG. It is sectional drawing of the defect inspection apparatus shown in FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Defect inspection apparatus, 2 ... Inspection object, 2a ... Outer curved surface (inspection surface), 2b ... Inner curved surface (inspection surface), 2d ... End surface (inspection surface), 3 ... Support plate (support member), 4A , 4B ... Conveying unit (conveying means), 5A, 5B ... Two-dimensional laser displacement meter, 6 ... Opening for inspection, 8 ... Slit, 18 ... Displacement meter controller (defect detecting means), 19 ... Personal computer (defect detecting means) , 30 ... Defect inspection device, 31 ... Support plate (support member), 32 ... Wall plate (support member), 33 ... Slit, 35 ... Space adjustment unit (space adjustment means), 36A, 36B ... Transport unit (transport means) , X: Inspection area.

Claims (5)

A defect inspection apparatus for continuously inspecting a surface state defect of a plurality of inspection objects,
A support member on which the inspection object is placed;
Transport means for transporting the inspection object placed on the support member to an inspection region of the support member;
Up and down are arranged so as to face each other across the inspection region, and laser light is irradiated on the inspection surfaces on both the upper and lower sides of the inspection object to receive the reflected light from each inspection surface, to each inspection surface A pair of two-dimensional laser displacement meters, each measuring a distance of
A defect inspection apparatus comprising: a defect detection unit that detects a defect in a surface state of the inspection object based on a measurement result of the pair of two-dimensional laser displacement meters. The support member has an inspection opening that forms the inspection region;
2. A slit having an opening width narrower than a width dimension of the inspection object is provided on each of right and left sides of the inspection opening along the conveyance direction of the inspection object. Defect inspection apparatus as described. The support member has a pair,
The pair of support members are arranged to extend parallel to each other,
The defect inspection apparatus according to claim 1, wherein each support member is provided with a slit having an opening width narrower than a width dimension of the inspection object and forming the inspection region.   The defect inspection apparatus according to claim 3, further comprising an interval adjusting unit that adjusts a distance between the pair of support members. A defect inspection method for continuously inspecting a surface state defect of a plurality of inspection objects,
The support member on which the inspection object is placed is arranged vertically so as to face each other across the inspection region of the support member, and each inspection is performed by irradiating the inspection surfaces on both the upper and lower sides of the inspection object with laser light. Preparing a pair of two-dimensional laser displacement meters for measuring the distance to each of the inspection surfaces by receiving reflected light from the surface;
Placing the inspection object on the support member, and conveying the inspection object to the inspection area in that state;
When the inspection object reaches the inspection area, simultaneously measuring the distance to each inspection surface of the inspection object by the pair of two-dimensional laser displacement meters;
And a step of detecting a surface state defect of the inspection object based on a measurement result of the pair of two-dimensional laser displacement meters.

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