JP2023097554A - Surface inspection device and surface inspection method - Google Patents

Abstract

To provide a surface inspection device and surface inspection method which can correctly determine an optical axis deviation of a light receiver with respect to an inspection object.SOLUTION: A surface inspection device 10 is configured to irradiate an inspection object W that is web-conveyed with inspection light from a light source 2, receive the inspection light passing through the inspection object W by a light receiver 5, detect a defect in the inspection object W on the basis of an output signal of the light receiver 5, irradiate a path roll 1 arranged in a visual area SA of the light receiver 5 and outside an area of the inspection object W with laser light from laser pointers 3, 4, receive laser reflection light reflected on the path roll 1 by the light receiver 5, and determine an optical axis deviation of the light receiver 5 with respect to the inspection object W on the basis of the laser reflection light received by the light receiver 5.SELECTED DRAWING: Figure 1

Description

The present invention relates to a surface inspection device and a surface inspection method.

As a surface inspection apparatus of this type, there is disclosed one that includes a light source for irradiating light onto the surface of a conveyed inspection object and a plurality of imaging devices for receiving reflected light from the inspection object (Patent Document 1). The surface inspection apparatus of Patent Document 1 includes a laser pointer that irradiates the surface of an object to be inspected with a laser beam having a brightness different from that of the light from the light source, and a diagnostic unit. , and detects a deviation in the installation state of the imaging device from the difference in the position of the image of the laser beam irradiation.

Patent No. 4901578

However, in the surface inspection apparatus described in Patent Document 1, the object irradiated with laser light by the laser pointer is the surface of the object to be inspected. There is a problem that the received amount of the reflected light fluctuates depending on the position of the imaging device, and it may not be possible to accurately detect whether or not there is a deviation in the installation state of the imaging device.

SUMMARY OF THE INVENTION An object of the present invention is to provide a surface inspection apparatus and a surface inspection method that can accurately determine the optical axis deviation of a light receiver with respect to an inspection object. do.

(1) A surface inspection apparatus according to the present invention irradiates an inspection object conveyed on a web with inspection light from a light source, receives the inspection light that has passed through the inspection object by a light receiver, and outputs the light from the light receiver. A surface inspection apparatus for detecting defects in the inspection object based on a signal, wherein a laser beam is emitted from a laser to an irradiation object placed within a visual field area of the light receiver and outside the area of the inspection object. Then, the laser reflected light reflected by the object to be irradiated is received by the light receiver, and the optical axis deviation of the light receiver with respect to the inspection target is determined based on the laser reflected light received by the light receiver. It is characterized by

(2) The surface inspection apparatus according to the present invention is the surface inspection apparatus according to (1), wherein at least one of the position, width, and intensity of the laser reflected light on the reflecting surface of the irradiation object is and calculating the deviation amount of the optical axis deviation based on.

(3) The surface inspection apparatus according to the present invention is the surface inspection apparatus according to (2), wherein the position of the reflected laser light is measured with reference to the edge of the visual field area of the light receiver. Characterized by

(4) The surface inspection apparatus according to the present invention is the surface inspection apparatus according to any one of (1) to (3), wherein the laser for irradiating the laser beam is perpendicular to the conveying direction of the inspection object. At least one is provided on the one end side in the direction to which the transfer direction is directed, and at least one is provided on the other end side in the direction orthogonal to the conveying direction.

(5) A surface inspection apparatus according to the present invention is the surface inspection apparatus according to any one of (1) to (4), wherein the irradiation object is a stationary member, and the inspection object is web-conveyed. It is characterized by being either a roller member.

(6) A surface inspection apparatus according to the present invention is the surface inspection apparatus according to any one of (1) to (5), wherein a surface of the object to be irradiated with the laser beam and a surface of the object to be inspected are irradiated with the laser beam. A surface of the object irradiated with the inspection light is arranged at the same plane height position.

(7) A surface inspection method according to the present invention has a light source for irradiating an inspection light onto a web-conveyed inspection object, and within a visual field area of a light receiver for receiving the inspection light passing through the inspection object, and an irradiation step of irradiating a laser beam from a laser onto an irradiation object placed outside the region of the inspection object; a light receiving step of receiving light with a light receiver, detecting a defect of the inspection object based on the inspection light received with the light receiver, and detecting the light of the light receiver with respect to the inspection target based on the laser reflected light. and a determination step of determining an axis deviation.

The surface inspection apparatus according to the present invention described in the above (1) irradiates an inspection light from a light source onto an inspection object conveyed as a web, receives the inspection light passing through the inspection object with a light receiver, A surface inspection device for detecting defects in an object to be inspected based on the output signal of the laser, which irradiates a laser beam from a laser onto an object to be inspected, which is placed within the field of view of the light receiver and outside the area of the object to be inspected. A light receiver receives the laser light reflected by the object to be irradiated, and determines the optical axis deviation of the light receiver with respect to the inspection target based on the reflected laser light received by the light receiver.

With this configuration, the surface inspection apparatus inspects the web-conveyed inspection object and determines the optical axis deviation of the light receiver with respect to the inspection object. In the surface inspection apparatus, a laser beam is emitted from a laser to an object to be irradiated, which is placed within the field of view of the light receiver and outside the area of the object to be inspected. The surface of the object to be irradiated with the laser beam is a stable surface with less variation than the surface of the object to be inspected. can do. Therefore, it is possible to accurately determine the optical axis deviation of the light receiver with respect to the inspection object based on the stable reflected laser light, and the reliability of the calibration of the light receiver is ensured.

In the surface inspection apparatus according to the present invention described in (2) above, the amount of optical axis misalignment is determined based on at least one of the position, width, and intensity of the laser reflected light on the reflecting surface of the irradiation object. calculate. With this configuration, it is possible to determine the deviation of the optical axis of the light receiver and determine the pattern of the deviation of the optical axis.

In the surface inspection apparatus according to the present invention described in (3) above, the position of the reflected laser light is measured with reference to the edge of the visual field area of the light receiver. With this configuration, the reference for judging the optical axis deviation of the light receiver is clarified, and since the position of the reflected laser light is within the visual field area of the light receiver, the position of the reflected laser light received by the light receiver is is grasped.

In the surface inspection apparatus according to the present invention described in (4) above, at least one laser for irradiating a laser beam is located on one end side of the inspection object in a direction perpendicular to the conveying direction. At least one is provided on the other end side of the. With this configuration, when an abnormality occurs in which the optical axis of the light receiver deviates in the direction in which the light receiver rotates about the optical axis, the deviation of the optical axis of the light receiver can be accurately determined.

In the surface inspection apparatus according to the present invention described in (5) above, the object to be irradiated is either a stationary member or a roller member that conveys the object to be inspected as a web. With this configuration, the laser light is not irradiated to the surface of the moving object to be inspected, and is irradiated to the stationary member and the roller member whose surface state is stable with little variation in the surface state. Therefore, compared with the case where the inspection object is irradiated with the laser beam, more stable laser reflected light can be obtained, and the optical axis shift of the light receiver with respect to the inspection object can be determined accurately. As a result, the reliability of the receiver calibration is ensured.

In the surface inspection apparatus according to the present invention described in (6) above, the surface of the irradiation object irradiated with the laser beam and the surface of the inspection object irradiated with the inspection light are at the same plane height position. are placed in

With this configuration, the distance from the laser beam-irradiated surface of the irradiation object to the light receiver is the same as the distance from the inspection light-irradiated surface of the inspection object to the light receiver. Therefore, the distance of the reflected light of the inspection light received by the light receiver is substantially the same as the distance of the reflected light of the laser light received by the light receiver, and the deviation of the optical axis of the light receiver can be accurately determined.

The surface inspection method according to the present invention described in (7) above has a light source for irradiating an inspection object conveyed on a web with inspection light, and a visual field region of a light receiver for receiving the inspection light passing through the inspection object. An irradiation step of irradiating a laser beam from a laser to an irradiation object placed inside and outside the area of the inspection object, and receiving the inspection light that has passed through the inspection object and the laser reflected light that has been reflected by the irradiation object. a light receiving step of receiving light with an optical receiver; and a determination step of detecting defects in an inspection object based on the inspection light received by the optical receiver and determining optical axis deviation of the optical receiver with respect to the inspection object based on laser reflected light. and

With this configuration, in the surface inspection method according to the present invention, the web-conveyed inspection object is inspected, and the misalignment of the optical axis of the light receiver with respect to the inspection object is accurately determined. A surface inspection method according to the present invention irradiates a laser beam from a laser onto an object to be irradiated, which is placed within the field of view of the light receiver and outside the region of the object to be inspected. The surface of the object to be irradiated with the laser beam is a stable surface with less variation than the surface of the object to be inspected. can do. Therefore, it is possible to accurately determine the optical axis deviation of the light receiver with respect to the inspection object based on the stable reflected laser light, and the reliability of the calibration of the light receiver is ensured.

ADVANTAGE OF THE INVENTION According to this invention, the surface inspection apparatus and surface inspection method which can determine the optical axis deviation of the light receiver with respect to an inspection object correctly can be provided.

BRIEF DESCRIPTION OF THE DRAWINGS It is a schematic diagram of the surface inspection apparatus which concerns on embodiment of this invention, FIG.1(1) shows a perspective view, FIG.1(2) shows a side view. BRIEF DESCRIPTION OF THE DRAWINGS It is a figure of the surface inspection apparatus which concerns on embodiment of this invention, FIG.2(1) shows explanatory drawing explaining the inspection light and laser beam which are irradiated to a pass roll and an inspection object, and FIG.2(2) shows 3A and 3B show explanatory diagrams for explaining the output signal of the photodetector. FIG. 2 is a schematic diagram of a portion for inspecting an object to be inspected by the surface inspection apparatus according to the embodiment of the present invention; FIG. 4 is an explanatory diagram for explaining an output signal of inspection light received by a photoreceiver of a portion for inspecting an inspection object excluding reflected laser light in the surface inspection apparatus according to the embodiment of the present invention; The figure explaining the optical axis abnormality (optical axis deviation of the width direction) of the surface inspection apparatus which concerns on embodiment of this invention. FIG. 4 is a diagram for explaining an optical axis abnormality (longitudinal optical axis deviation) of the surface inspection apparatus according to the embodiment of the present invention; The figure explaining the optical axis abnormality (optical axis shift|offset|difference of a rotation direction) of the surface inspection apparatus which concerns on embodiment of this invention. FIG. 4 is a process diagram of a surface inspection method using the surface inspection apparatus according to the embodiment of the present invention; The table|surface which shows the pattern of an optical axis abnormality. It is a schematic diagram of the surface inspection apparatus which concerns on the modification 1 of embodiment of this invention, FIG.8(1) shows a top view, FIG.8(2) shows a side view. It is a schematic diagram of the surface inspection apparatus which concerns on the other modified example 2 of embodiment of this invention, FIG.9(1) shows a front view, FIG.9(2) shows a side view.

A surface inspection apparatus 10 and a surface inspection method according to an embodiment to which the surface inspection apparatus and surface inspection method according to the present invention are applied will be described with reference to the drawings.

First, the surface inspection device 10 according to the embodiment will be described. As shown in FIGS. 1(1) and 1(2), the surface inspection apparatus 10 includes a pass roll 1, a light source 2, laser pointers 3 and 4, a light receiver 5, a signal processing section 6, and a display section. 7.

The surface inspection apparatus 10 detects defects of the inspection object W such as scratches, stains, and foreign matter adhesion on the surface of the inspection object W in the production line of the inspection object W, and signals the optical axis deviation of the light receiver 5. The processing unit 6 makes a determination, and the display unit 7 displays these signals and/or determination results. The inspection object W is made of a so-called web material such as a long sheet-like steel plate or film. The surface inspection apparatus 10 can determine the optical axis deviation of the light receiver 5 without interfering with the so-called online inspection for inspecting the inspection object W during the operation of the production line.

As shown in FIG. 1(1), the pass roll 1 is composed of cylindrical roller members. The pass roll 1 is arranged so that its axial direction extends in a direction parallel to the inspection object W and perpendicular to the conveyance direction of the inspection object W. As shown in FIG. It is rotatably supported about an axis, and has a structure in which the web is transported while contacting the inspection object W at the central portion in the axial direction. In this embodiment, the lower surface of the inspection object W transported horizontally as indicated by the arrow a is contacted to change the transport direction downward. The pass roll 1 corresponds to a roller member of the surface inspection apparatus according to the present invention and an object to be irradiated with a laser beam. The direction of web transport may be the direction opposite to arrow a.

The light source 2 is composed of a light-emitting device such as a light-emitting diode that irradiates the surface of the inspection object W with inspection light 2a. As shown in FIG. 1(2), the light source 2 is positioned downstream of the line where the axis J of the pass roll 1 and the optical axis CS of the light receiver 5 intersect in the conveying direction of the inspection object W. and is arranged at a position separated from the pass roll 1. The light source 2 is fixed to a fixing member (not shown).

In FIG. 1(2), the light source 2 is arranged on the downstream side in the conveying direction, but the light source 2 and the light receiver 5 are specular reflection or diffuse reflection, and the defect portion E of the inspection object W (see FIG. 4) can be detected, and the light source 2 may be arranged at another position such as the upstream side.

The light source 2 emits light when supplied with power, and irradiates the surface of the inspection object W on the pass roll 1 with inspection light 2a. As shown in FIGS. 1(1) and 2(1), the inspection light 2a is irradiated over the entire area from one side end 1a to the other side end 1b of the pass roll 1 which is substantially the same as the visual field area SA of the light receiver 5. It is carried out over the entire width of the area WA from the end on one side in the width direction of the object W to be inspected to the end on the other side. As shown in FIG. 1(2), the light source 2 is directed toward a linear region where a virtual plane including the axis J of the pass roll 1 and the optical axis CS of the light receiver 5 intersects the surface (peripheral surface) of the pass roll 1. is irradiated with the inspection light 2a. The light source 2 irradiates the pass roll 1 with inspection light 2a from below the virtual plane. Since the light source 2 irradiates the inspection light 2a in a direction that obliquely crosses the virtual plane, the reflected light specularly reflected by the surface of the inspection object W and the pass roll 1 is not received by the light receiver 5 and is diffusely reflected. Reflected light is received by the light receiver 5 . The amount of reflected light received by the light receiver 5 is smaller than that of the reflected light specularly reflected on the surface of the inspection object W and the pass roll 1 .

The laser pointers 3 and 4 have, for example, an LD light source using an LD (Laser Diode) as a light emitting element, and are positioned near one end 1a and near the other end 1b of the pass roll 1, respectively. are placed. Laser pointers 3 and 4 irradiate laser beams 3a and 4a for calibrating the optical axis CS of the light receiver 5 from the LD light source.

As shown in FIGS. 1(2) and 2(1), the laser pointers 3 and 4 include the optical axis LS on a virtual plane including the axial center J of the pass roll 1 and the optical axis CS of the light receiver 5. 2(1) and outside the visual field area SA of the light receiver 5 surrounded by the dashed line in FIG. 2(1). The laser pointers 3 and 4 are fixed to fixing members (not shown).

The laser pointers 3 and 4 irradiate laser beams 3a and 4a on the surface of the pass roll 1, within the visual field area SA of the light receiver 5 and outside the area of the inspection object W. FIG. The thickness of the object W to be inspected is thin, and the surfaces of the pass rolls 1 irradiated with the laser beams 3a and 4a are at substantially the same plane height position as the surface of the object W to be inspected.

In this embodiment, the irradiation shape of the laser beams 3a and 4a is circular, and the shape of the reflected laser beams 3b and 4b formed on the surface of the pass roll 1 is also circular, and the size thereof is, for example, about 5 mm to 10 mm in diameter. is. Note that the irradiation shape of the laser beams 3a and 4a may be a shape other than a circle. For example, the shape of the reflected laser beams 3b and 4b formed on the surface of the pass roll 1 may be a vertically long rectangular shape extending obliquely with respect to the circumferential direction of the pass roll 1. FIG. When the shape of the reflected laser beams 3b and 4b is rectangular, the angle (°) of inclination with respect to the axis J of the pass roll 1 is set, one side end portion 1a is irradiated, and the left-right inverted shape of the laser beam is applied to the other side. By irradiating the side end portion 1b, the shift amount of the optical axis CS of the light receiver 5 in the transport direction of the inspection object W and the optical axis CS of the light receiver 5 in the direction orthogonal to the transport direction of the inspection object W are changed. It is possible to grasp both the amount of deviation and the amount of deviation. When the shape of the reflected laser beams 3b and 4b formed on the surface of the pass roll 1 is rectangular, there is no limitation on the angle of inclination. The deviation amount of the optical axis CS of the device 5 can be easily calculated.

As shown in FIG. 2, the laser pointer 3 is arranged so that the incident angle α1 (°) and the reflection angle α2 (°) to the irradiation position of the laser beam irradiated on the pass roll 1 are equal. That is, the laser pointer 3 is arranged so that the pass roll 1 is irradiated with the laser light 3a, and the light receiver 5 receives the laser reflected light 3b specularly reflected on the surface of the pass roll 1. FIG.

The laser pointer 4 is constructed in the same manner as the laser pointer 3, is composed of an LD light source using an LD as a light emitting element, and is positioned near the other end 1b of the pass roll 1. FIG. A laser beam 4a for calibrating the optical axis CS of the light receiver 5 is emitted from the LD light source.

As with the laser pointer 3, the incident angle β1 (°) and the reflection angle β2 (°) of the laser beam 4a emitted from the laser pointer 4 to the irradiation position are also arranged to be equal. The light receiver 5 is arranged so that the reflected laser light 4b is received. Note that either one of the laser pointers 3 and 4 may be provided. Laser pointers 3 and 4 correspond to lasers of the surface inspection apparatus according to the present invention.

The light receiver 5 has a plurality of imaging elements such as a known CCD (Charge-Coupled Device) image sensor or CMOS (Complementary Metal-Oxide-Semiconductor) image sensor, and each imaging element is arranged linearly. It is composed of a line camera with The photodetector 5 is connected to the signal processing section 6 as shown in FIGS. 1(1) and 1(2).

As shown in FIG. 1B, the light receiver 5 has a reference position where the optical axis CS of the light receiver 5 is perpendicular to the axis J of the pass roll 1, which is indicated by the one-dot chain line on the above virtual plane. The waveform of the laser reflected light at the reference position is recorded in advance together with the positions of the laser reflected lights 3b and 4b. The light receiver 5 is fixed to a fixed member such as a platform (not shown) that can change the angle of the light receiver. Adjustment can be made to return the axis CS to the reference position. The light receiver 5 moves from the reference position in (1) the direction along the axis J of the pass roll 1 (the width direction of the object to be inspected), and (2) the direction orthogonal to the optical axis CS at the reference position and the axis of the pass roll 1. There is a possibility of deviation in at least one of the direction away from J in the radial direction of the pass roll 1 (longitudinal direction of the inspection object) and (3) the direction of rotation about the optical axis CS of the reference position.

As shown in FIG. 3, the light receiver 5 irradiates the inspection object conveyed as a web in the conveying direction indicated by the arrow a from the light source 2 and reflects off the surface of the inspection object W, i.e., passes through the inspection object W. The inspecting light 2 a is received and an output signal is transmitted to the signal processing unit 6 .

The output signal, as shown in FIG. 4, is a voltage (V) signal at each position in the width direction (x direction) of the inspection object W perpendicular to the transport direction of the web transport. Of the inspection light emitted from the light source 2, the light receiver 5 does not receive specular inspection light that is reflected on the reflecting surface at the same angle of incidence and reflection. Receives diffusely reflected interrogation light that is diffused. In this embodiment, a surface inspection apparatus in which the light receiver 5 receives diffuse reflection inspection light will be described, but the present invention can also be applied to a surface inspection apparatus in which the light receiver 5 receives specular reflection inspection light. be.

The inspection light is diffusely reflected in a defective portion of the inspection object W, and the inspection light is specularly reflected in a normal portion without a defect. Accordingly, the receiver 5 receives relatively more light from the defected portion and relatively less light from the other defect-free portion. As a result, as shown in FIG. 4, the output signal of the photodetector 5 becomes a relatively high voltage that exceeds the predetermined criterion Th at the defect portion E, and falls below the criterion Th at the portion without defects. It becomes a relatively low voltage.

Further, as shown in FIG. 2(1), the light receiver 5 receives the reflected laser beams 3b and 4b which are emitted from the laser pointers 3 and 4 and specularly reflected from the surface of the pass roll 1, and receives the received laser reflected beams 3b and 4b. 4b is converted into an electrical signal and transmitted to the signal processing unit 6 as an output signal. The light receiver 5 receives the reflected laser beams 3b and 4b that are specularly reflected from the surface of the pass roll 1 from the laser beams 3a and 4a emitted from the laser pointers 3 and 4. The voltage will be high. The laser pointers 3 and 4 are installed at an angle of specular reflection with respect to the light receiver 5, so that a large amount of light incident on the light receiver 5 can be ensured, so that it can be clearly distinguished from the inspection light.

Similar to the output signal of the inspection light 2a, the output signals of the laser reflected light beams 3b and 4b are, as shown in FIG. is output as a voltage (V) signal at the position of . This output signal includes signals of the position, width and intensity of the laser reflected light 3b, 4b on the surface of the pass roll 1. FIG. In FIG. 2(2), the horizontal axis indicates the position in the width direction of the pass roll 1, and the vertical axis indicates the height of the voltage.

The voltage output from the photodetector 5 is higher at the position where the specularly reflected laser beams 3b and 4b are received than at the surroundings. The position where the reflected laser beams 3b and 4b are received is represented by the position of the rectangle that is the peak value of the voltage obtained from the signal output from the photodetector 5. Specifically, it is one side of the visual field area SA of the photodetector 5. It is represented by a position x1 measured with respect to the end T1 and a position x2 measured with respect to the other end T2.

In the example shown in FIG. 2(2), the position x1 of the reflected laser beam 3b is located at a distance .delta.1 from one end T1 of the visual field area SA of the light receiver 5 toward the center of the pass roll 1. In the example shown in FIG. The width of the reflected laser beam 3b is represented by the width t1 of the voltage rectangle obtained from the signal output from the photodetector 5. FIG. The intensity of the reflected laser beam 3b is represented by the voltage height h1 obtained from the signal output from the photodetector 5. FIG.

Similarly, the position x2 of the reflected laser beam 4b is a position away from the other end T2 of the visual field area SA of the light receiver 5 toward the center of the pass roll 1 by a distance δ2. The width of the reflected laser beam 4b is represented by the width t2 of the voltage rectangle obtained from the signal output from the photodetector 5. FIG. The intensity of the reflected laser light 4b is represented by the voltage height h2 obtained from the signal output from the photodetector 5. FIG.

In addition to the above, the positions of the reflected laser beams 3b and 4b are obtained from the signals output from the photodetector 5. may be represented by the length between

With regard to the position, width and intensity signals of the reflected laser light, the case where the optical axis CS of the light receiver 5 is deviated and the optical axis is abnormal will be described with reference to the drawings.

When the optical axis CS of the light receiver 5 deviates in the width direction, for example, as shown in FIG. Since the positions of the reflected laser beams 3b and 4b received by the receiver 5 are shifted in the width direction, as shown in FIG. From the position indicated by the solid line, it deviates in the direction of the other end T2 as indicated by the broken line.

The rectangular portion representing the laser reflected light 3b in the output signal of the photodetector 5 is a distance δ1 from one end T1 of the visual field area SA of the photodetector 5 toward the center of the pass roll 1 when the optical axis CS is at the reference position. It is located at a distant position x1. When the optical axis CS is deviated from the reference position toward the one side end 1a of the pass roll 1, it is separated from the one side end T1' of the visual field area SA of the light receiver 5 toward the center of the pass roll 1 by a distance δ1'. position x1'. Similarly, when the optical axis CS is at the reference position, the position of the reflected laser beam 4b is at a position x2 which is a distance δ2 away from the other end T2 of the visual field area SA of the light receiver 5 toward the center of the pass roll 1. . When the optical axis CS deviates from the reference position toward the one side end 1a of the pass roll 1, the other side end T2' of the visual field area SA of the light receiver 5 is separated from the other side end T2' toward the center of the pass roll 1 by a distance δ2'. position x2'.

When the optical axis CS of the light receiver 5 is shifted in the longitudinal direction, that is, in the conveying direction of the inspection object W, for example, as shown in FIG. If it shifts to the upstream side (upper side in the drawing), the amount of light received by the light receiver 5 of the reflected laser beams 3b and 4b decreases. The rectangular portions representing the reflected lights 3b and 4b change from the size indicated by the solid line to the size indicated by the dashed line.

The laser reflected light 3b reflected on the surface of the pass roll 1 represents the laser reflected light 3b in the output signal of the light receiver 5 shown in FIG. The position of the rectangular portion is the position x1' away from one end T1' of the visual field area SA of the light receiver 5 toward the center of the pass roll 1 by the distance δ1', and the width t is also narrowed to the width t'. , its height h is also reduced to a height h'. Similarly, the rectangular portion representing the reflected laser beam 4b also becomes narrower and lower in height.

If the light receiver 5 is shifted in the direction of rotation, that is, in the direction in which the light receiver rotates about the optical axis CS, for example, as shown in FIG. 5C(1), it rotates counterclockwise about the optical axis CS. Then, the amounts of the reflected laser beams 3b and 4b received by the photodetector 5 are reduced, so that the rectangular portions representing the reflected laser beams 3b and 4b in the output signal of the photodetector 5 are reduced as shown in FIG. 5C(2). is reduced from the size indicated by the solid line to the size indicated by the broken line, and its position also changes so as to shift toward the center of the pass roll 1 .

The reflected laser light 3b reflected on the surface of the pass roll 1 is received as shown in FIG. The rectangular portion representing the laser reflected light 3b in the output signal of the device 5 is located at the position x1' away from one end T1' of the visual field area SA of the light receiver 5 toward the center of the pass roll 1 by a distance δ1'. , the width t is also narrowed to be the width t', and the height h is also reduced to be the height h'. Similarly, the rectangular portion representing the reflected laser beam 4b also moves in position, narrows in width, and decreases in height. Then, the width of the inspection object W becomes wider on both sides.

The signal processing unit 6 is composed of a microcomputer having a central processing unit that executes arithmetic processing according to a program and a storage device that stores programs, data, and the like.

The signal processing unit 6 detects defects in the inspection object W based on the voltage output from the photodetector 5 by receiving the inspection light. Further, the signal processing unit 6 determines whether or not the optical axis CS of the light receiver 5 is deviated from the inspection object W based on the voltage output from the light receiver 5 by receiving the reflected laser light. Further, the signal processing unit 6 can also calculate the deviation amount of the optical axis CS of the light receiver 5 based on at least one of the positions, widths, and intensities of the reflected laser beams 3b and 4b. The signal processing unit 6 can monitor deviations of the optical axis CS in the width direction, the longitudinal direction, and the rotation direction of the light receiver 5 shown in FIGS. 5A, 5B, and 5C, and detect an optical axis abnormality at an early stage.

As shown in FIG. 4, the signal processing unit 6 determines whether or not the voltage of the signal of the inspection light exceeds the determination reference Th in the determination of the inspection light. If the voltage of the signal of the inspection light output from the inspection object W does not exceed the criterion Th, it is treated as a non-defective product. is treated as if it exists. The criterion Th is appropriately selected based on the specifications such as the size, structure, material, and shape of the inspection object W, and data such as setting specifications and experimental values of the surface inspection apparatus 10 .

In the judgment of the laser reflected light of the signal processing unit 6, it is judged whether the voltage output from the light receiver 5 is within the allowable range with respect to the voltage at the reference position, that is, whether or not there is an optical axis misalignment. The amount of deviation of the optical axis CS of the light receiver 5 is calculated, and it is determined whether or not the deviation is within the allowable range. If the waveform of the signal voltage of the reflected laser light does not exceed the allowable range for the voltage at the waveform reference position, it is determined that there is no optical axis deviation, and if it exceeds the allowable range for the voltage at the waveform reference position , and determines that there is optical axis deviation, and transmits these signals and/or determination results to the display unit 7 . Further, the following calculation and determination of the amount of optical axis deviation can be performed as necessary.

If the calculated deviation amount is within the allowable range, the result is transmitted to the display unit 7 assuming that there is no optical axis abnormality. If the amount of deviation is not within the allowable range, the result is transmitted to the display unit 7 assuming that there is an optical axis abnormality. The permissible range of the amount of deviation is appropriately selected based on specifications such as the size, structure, material, and shape of the inspection object W, and data such as setting specifications and experimental values of the surface inspection apparatus 10. .

For example, when the rectangular portions representing the reflected laser beams 3b and 4b in the output signal of the photodetector 5 are shifted in the direction of the other end T2 as indicated by the dashed line in FIG. 5A(2), the reference position An optical axis abnormality in the width direction is determined based on the amount of deviation from the .

In addition, the rectangular portion representing the reflected laser light in the output signal of the photodetector 5 has a height h lower and a width t becomes smaller, the position is almost unchanged, and the rectangular portion of the other end T2 is also the same. exceeds the allowable range, it is determined that there is an optical axis abnormality in the longitudinal direction.

In addition, the rectangular portion representing the reflected laser light in the output signal of the photodetector 5 has a height h lower and a width t is shifted in the direction of the other side end T2, and similarly in the rectangular portion of the other side end T2, the height h is decreased, the width t is decreased, and the position is shifted to the one side If there is a deviation in the direction of the side end T1, it is determined that the optical axis is abnormal in the rotation direction based on the deviation amount from the reference position. It is determined that there is an optical axis abnormality in .

The display unit 7 is composed of a display device such as an LED or a liquid crystal display, and is connected to the signal processing unit 6 . The display unit 7 can display the determination result sent from the signal processing unit 6, that is, the optical axis abnormality in the width direction, the longitudinal direction, or the rotation direction and the amount of deviation of the optical axis CS of the light receiver 5. FIG.

Next, an example of the surface inspection method according to the embodiment will be described with reference to the drawings.
The surface inspection method according to the embodiment includes, as shown in FIG. It includes steps of determination of the measurement result of reflected light (step S6), determination and display of optical axis abnormality (step S7), and optical axis adjustment (step S8).

Furthermore, the surface inspection method includes light control processing (step S9), irradiation of inspection light (step S10), light reception by the light receiver (step S11), determination of defects (step S12), and defect processing (step S13) and whether or not the surface inspection should be continued (step S14). Each step is performed in order.

The measurement of the reflected laser light (steps S3 to S5) includes measurement of the position of the reflected laser light (step S3), measurement of the width of the reflected laser light (step S4), and measurement of the intensity of the reflected laser light (step S5). and

It should be noted that the laser beam irradiation (step S1) of the surface inspection method by the surface inspection apparatus 10 according to the embodiment corresponds to the irradiation step of the surface inspection method according to the present invention, and the light reception of the light receiver (step S2) corresponds to the present method. Corresponding to the light receiving step of the surface inspection method according to the invention, measurement of reflected laser light (steps S3 to S5), determination of measurement results of reflected laser light (step S6), determination and display of optical axis abnormality (step S7) corresponds to the determination step of the surface inspection method according to the present invention.

In the laser beam irradiation (step S1), as shown in FIG. Circular laser beams are irradiated from the laser pointers 3 and 4 to irradiation positions of the laser beams at substantially the same plane height position as the surface of the object W. As shown in FIG. The irradiation of the laser light may be performed while the inspection object W is conveyed as a web by the surface inspection apparatus 10 and the surface inspection is being performed, or during the calibration of the light receiver 5 before the surface inspection is performed. good too.

In the light receiving by the light receiver (step S2), the light receiver 5 receives laser reflected light beams 3b and 4b which are emitted from the laser pointers 3 and 4 and specularly reflected from the surface of the pass roll 1, as shown in FIG. 2(1). do. The light receiver 5 converts the reflected laser beams 3b and 4b into electrical signals, which are transmitted to the signal processing unit 6 as output signals.

The output signal, as shown in FIG. 2(2), is a voltage (V) signal at a position x in the width direction of the pass rolls 1 perpendicular to the transport direction of the web. This output signal includes the position x, width t and intensity h of the reflected laser beam.

Next, the signal processing unit 6 performs processing for judging an optical axis abnormality of the light receiver 5 based on the output signal of the laser reflected light received by the light receiver 5 . In the example shown in FIG. 2(2), in the visual field area SA of the light receiver 5, the voltage of the portion of the laser reflected light reflected on the surface of the pass roll 1 is the highest, followed by the surface of the pass roll 1 and other than the laser reflected light. The voltage of the part is high, and the voltage of the area of the inspection object W is the lowest.

In the measurement of the position of the reflected laser light (step S3), the distance .delta. , the width t of the rectangular portion is obtained, and the height h of the rectangular portion is obtained in the measurement of the intensity of the reflected laser light (step S5).

In step S6, it is determined whether or not the measurement results (position x/width t/intensity h) of the reflected laser light in steps S3 to S5 are within the allowable range. Here, the amount by which the signal-processed voltage deviates from the reference position, that is, the amount of deviation of the optical axis CS of the light receiver 5 is calculated, and it is determined whether or not the calculated amount of deviation is within the allowable range. be. Note that the amount of deviation is calculated based on at least one of the position as the position of the reflected laser light, the width, and the intensity of the reflected laser light.

If it is determined in step S6 that the measurement result (deviation amount) of the reflected laser light is within the allowable range (YES in step S6), it is determined that there is no optical axis abnormality in the light receiver 5, and the process proceeds to step S9 and subsequent steps. At this time, processing may be performed to display the determination result that the optical axis of the light receiver 5 is not abnormal on the display unit 7 .

On the other hand, if it is determined that the measurement result of the reflected laser light is not within the allowable range (NO in step S6), the process advances to step S7 to determine the pattern of the optical axis abnormality, and display the determination content on the display unit 7. Display processing is performed.

In the process of judging and displaying the optical axis abnormality in step S7, it is identified which one of the plurality of optical axis abnormality patterns corresponds based on the measurement results in steps S3 to S5. Then, based on the identification result, it is determined whether the optical axis has an abnormality in the width direction, the longitudinal direction, or the rotation direction, and/or the deviation amount is calculated and displayed on the display unit 7. is done.

FIG. 7 is a table showing patterns of optical axis abnormalities.
For example, if the position measurement result in step S3 is abnormal and both the width measurement result in step S4 and the strength measurement result in step S5 are within the allowable range, it is determined that there is an abnormality in the width direction. If the position measurement result of step S3 is within the allowable range and both the width measurement result of step S4 and the strength measurement result of step S5 are abnormal, it is determined that there is an abnormality in the longitudinal direction. If the position measurement result in step S3, the width measurement result in step S4, and the intensity measurement result in step S5 are all abnormal, it is determined that there is an abnormality in the rotation direction or other optical axis abnormality.

In step S7, when the abnormality of the optical axis is determined and the abnormality of the optical axis of the light receiver 5 is displayed on the display unit 7, the process proceeds to step S8.

In the optical axis adjustment (step S8), the optical axis CS of the light receiver 5 is adjusted to the normal position based on the abnormal optical axis pattern and the deviation amount displayed by the display unit 7. FIG. The light receiver 5 is provided with an optical axis adjustment device (not shown) that adjusts the optical axis CS. automatically adjust the optical axis CS of the light receiver 5 to the normal position. Note that the optical axis adjustment may be performed by an operator.

When the optical axis adjustment in step S8 is completed, the process proceeds to step S1, and laser light irradiation is performed again (step S1).

In the light adjustment process (step S9), the volume of the illumination as the inspection light radiated on the surface of the inspection object W by the light source 2 is adjusted so that the inspection light radiated on the surface of the inspection object W has an optimum brightness. is set to be as small as possible.

In the irradiation of the inspection light (step S10), the surface of the inspection object W is irradiated with the inspection light from the light source 2, as shown in FIGS. The irradiation of the inspection light is performed in the same range as the range of the visual field area SA of the light receiver 5 shown in FIG. 2(1).

In the light reception of the light receiver (step S11), the light receiver 5 receives the inspection light emitted from the light source 2 and reflected from the surface of the inspection object W, as shown in FIG. 1(1). The received inspection light is converted into an electric signal by the light receiver 5 and transmitted to the signal processing unit 6 as an output signal. The output signal is, as shown in FIG. 4, a voltage (V) signal at a position in the width direction of the pass rolls 1 perpendicular to the conveying direction of the web.

Next, the signal processing unit 6 performs signal processing based on the signal of the inspection light received by the light receiver 5 and output.

In the determination of defects (step S12), defects on the surface of the inspection object W shown in FIG. 4 are detected. The signal processing unit 6 determines whether or not the voltage signal output from the photodetector 5 has a portion exceeding the determination reference Th indicated by the dashed line in FIG.

If there is no portion where the voltage signal output from the photodetector 5 exceeds the criterion Th, it is determined that there is no defect in the inspection object W (NO in step S12), and the process proceeds to step S14 to determine whether the surface inspection should be continued. . On the other hand, if there is a portion where the voltage signal output from the photodetector 5 exceeds the criterion Th, it is determined that there is a defect on the surface of the inspection object W (YES in step S12), and the process proceeds to defective product processing in step S13. .

In the defective product processing (step S13), the inspection object W having a defect on the surface is processed as a defective product. The fact that there is a defect in the inspection object W is fed back to the web production line management.

In whether or not to continue the surface inspection (step S14), it is determined whether or not the surface inspection of the web-conveyed inspection object W is necessary to continue. If it is determined that the surface inspection needs to be continued (YES in step S14), the process proceeds to irradiation of the inspection light (step S10), and the surface inspection of the inspection object W is continued. . On the other hand, if it is determined that the continuation of the surface inspection is not necessary in step S14 (NO in step S14), the surface inspection of the inspection object W ends.

Effects of the surface inspection apparatus 10 and the surface inspection method according to the present embodiment will be described below.

(1) The surface inspection apparatus 10 according to the embodiment irradiates the inspection light from the light source 2 onto the inspection object W conveyed on the web, receives the inspection light through the inspection object W by the light receiver 5, and receives the light. It has a configuration for detecting defects in the inspection object W based on the output signal of the device 5 . Then, the surface inspection apparatus 10 irradiates laser beams from the laser pointers 3 and 4 to the surface of the pass roll 1 which is arranged within the visual field area SA of the light receiver 5 and outside the area of the inspection object W, and the pass roll 1 is irradiated with laser light. The light receiver 5 receives each laser reflected light reflected by the light receiver 5, and determines the optical axis deviation of the light receiver 5 with respect to the inspection object W based on each laser reflected light received by the light receiver 5. .

With this configuration, the surface inspection apparatus 10 can detect defects in the inspection object W, and can accurately determine the optical axis deviation of the light receiver 5 with respect to the inspection object W even during the inspection of the inspection object W. It is possible to obtain the effect that the fluctuation of the optical axis of the light receiver 5 can be monitored.

In addition, since the surface inspection apparatus 10 irradiates the surface of the pass roll 1, which is arranged within the visual field area SA of the light receiver 5 and outside the area of the inspection object W, from the laser pointers 3 and 4, respectively, It is possible to obtain an effect that a stable surface with little variation can be irradiated with a laser beam. The surface inspection apparatus 10 can be used during the operation of the production line, and can determine the optical axis deviation of the light receiver 5 without interfering with the so-called online inspection for inspecting the inspection object W. The deviation of the optical axis of the device 5 can be discovered at an early stage.

Further, since the laser reflected light reflected from the stable surface of the pass roll 1 is received by the light receiver 5, the deviation of the optical axis of the light receiver 5 with respect to the inspection object W can be accurately determined based on the stable reflected laser light. and the reliability of the calibration of the photodetector 5 can be ensured. When the surface of the object to be inspected W is irradiated with a laser beam as in the conventional technology, the amount of reflected laser light fluctuates according to the surface state of the object to be inspected W, such as its surface roughness, shape and color. This solves the problem of inaccurate detection.

(2) In the surface inspection apparatus 10 according to the embodiment, the optical axis CS of the light receiver 5 is determined based on at least one of the position, width, and intensity of the reflected laser light received and output by the light receiver 5. is calculated. With this configuration, it is possible to determine the deviation of the optical axis of the light receiver 5 and determine the pattern of the deviation of the optical axis.

(3) In the surface inspection apparatus 10 according to the embodiment, the position of the reflected laser light is measured with reference to the edge of the visual field area SA of the light receiver 5 . This configuration clarifies the criteria for judging the optical axis deviation of the light receiver 5, and since the position of the reflected laser light is within the visual field area SA of the light receiver 5, An effect is obtained that the position of the reflected light can be grasped.

(4) The surface inspection apparatus 10 according to the embodiment has laser pointers 3 and 4 that emit laser light. , and at least one laser pointer 4 is provided on the other end side 1b in the direction orthogonal to the conveying direction. With this configuration, when an abnormality occurs in which the optical axis CS of the light receiver 5 deviates in the direction in which the light receiver rotates about the optical axis CS, the deviation of the optical axis CS of the light receiver 5 can be accurately determined. .

(5) In the surface inspection apparatus 10 according to the embodiment, the object irradiated with laser light is the pass roll 1 that conveys the inspection object W as a web. With this configuration, the laser beam does not irradiate the surface of the moving object W to be inspected, and has the effect of irradiating a member with a stable surface condition with little variation in the surface condition. Therefore, compared with the case where the inspection object W is irradiated with the laser beam, more stable laser reflected light can be obtained, and the optical axis deviation of the light receiver 5 with respect to the inspection object W can be accurately determined. As a result, the reliability of calibration of the photodetector 5 is ensured.

(6) In the surface inspection apparatus 10 according to the embodiment, the surface of the pass roll 1 irradiated with the laser light and the surface of the inspection object W irradiated with the inspection light are arranged at the same plane height position. . With this configuration, the distance from the laser beam-irradiated surface of the irradiation object to the light receiver is the same as the distance from the inspection light-irradiated surface of the inspection object to the light receiver. Therefore, the distance of the reflected light of the inspection light received by the light receiver 5 and the distance of the reflected light of the laser light received by the light receiver 5 are substantially the same, and the amount of deviation of the optical axis CS of the light receiver 5 can be accurately determined. The effect of being able to obtain is obtained. In addition, since the object W to be inspected is conveyed on the pass rolls 1, the surface of the object W to be inspected that is irradiated with the inspection light can easily be positioned at the same plane height as the surface of the pass rolls 1 that is irradiated with the laser beam. It is possible to obtain the effect of being able to

(7) The surface inspection method according to the embodiment has a light source for irradiating inspection light onto the web-conveyed inspection object W, and the visual field area SA of the light receiver 5 that receives the inspection light passing through the inspection object W. an irradiation step (step S1) of irradiating laser beams from laser pointers 3 and 4 to the pass rolls 1 arranged inside and outside the region of the inspection object W; A light receiving step (step S2) of receiving the laser reflected light reflected by the light receiving device 5, detecting a defect of the inspection object W based on the inspection light received by the light receiving device 5, and determination steps (steps S3 to S7) for determining the optical axis deviation of the light receiver 5 with respect to the inspection object W.

With this configuration, the surface inspection method can detect defects in the inspection object W, and can accurately determine the optical axis deviation of the light receiver 5 with respect to the inspection object W even during inspection of the inspection object W. , the variation of the optical axis of the light receiver 5 can be monitored.

In the surface inspection method, laser beams are irradiated from the laser pointers 3 and 4 to the surface of the pass roll 1, which is arranged within the visual field area SA of the light receiver 5 and outside the area of the inspection object W, so that variations occur. It is possible to irradiate a laser beam onto a stable surface with less stress. The surface inspection method can also be used during the operation of the production line, and can determine the optical axis deviation of the light receiver 5 without interfering with the so-called online inspection for inspecting the inspection object W. 5 can be detected at an early stage.

Further, since the laser reflected light reflected from the stable surface of the pass roll 1 is received by the light receiver 5, the deviation of the optical axis of the light receiver 5 with respect to the inspection object W can be accurately determined based on the stable reflected laser light. and the reliability of the calibration of the photodetector 5 can be ensured. When the surface of the object to be inspected W is irradiated with a laser beam as in the conventional technology, the amount of reflected laser light fluctuates according to the surface state of the object to be inspected W, such as its surface roughness, shape and color. This solves the problem of inaccurate detection.

In the surface inspection apparatus 10 according to the embodiment, the inspection object W is transported by the pass rolls 1, the surface of the inspection object W transported on the pass rolls 1 is inspected, and the surface of the pass rolls 1 is irradiated with a laser beam. A case where a structure including the laser pointers 3 and 4 is used has been described. However, the surface inspection apparatus according to the present invention may be configured with a structure other than that for irradiating the surface of the pass roll 1 with a laser beam.

For example, the surface inspection apparatus according to the present invention may be configured with a surface inspection apparatus 10A according to Modification 1 or a surface inspection apparatus 10B according to Modification 2 below. When the surface inspection device 10A and the surface inspection device 10B have the same configuration as the surface inspection device 10 according to the embodiment, the same reference numerals are used and the description of the configuration is omitted.

(Modification 1)
A surface inspection apparatus 10A according to Modification 1 will be described below with reference to the drawings.
As shown in FIGS. 8(1) and 8(2), the surface inspection apparatus 10A according to Modification 1 includes a pass roll 1, a pass roll 1A having the same structure as the pass roll 1, a light source (not shown), and laser pointers 3 and 4. , stationary members 11 and 12 as irradiation objects, a light receiver 5, a signal processing section (not shown), and a display section. As with the surface inspection apparatus 10 according to the embodiment, the surface inspection apparatus 10A detects defects on the surface of the inspection object W, determines optical axis deviation of the light receiver 5, and displays the result on the display unit. have.

The inspection object W of the surface inspection apparatus 10A according to Modification 1 is conveyed by pass rolls 1 and 1A. The light source 2 irradiates inspection light onto the inspection object W positioned on a line L that is positioned between the pass rolls 1 and the pass rolls 1A in the transport direction and perpendicular to the transport direction. The inspection light is reflected by the surface of the inspection object W, that is, passes through the inspection object W and is received by the light receiver 5 . The stationary member 11 is arranged in a direction orthogonal to the conveying direction and at a position separated from the one side end W1 of the inspection object W, and is fixed to a fixing member (not shown).

The stationary member 12, like the stationary member 11, is arranged in a direction orthogonal to the conveying direction and is separated from the other end W2 of the inspection object W in the width direction of the inspection object W. not fixed to a fixed member. The stationary member 11 and the stationary member 12 are positioned so that the straight line connecting the center of the surface of the stationary member 11 and the center of the surface of the stationary member 12 and the line L overlap.

The surface of the stationary member 11, the surface of the stationary member 12, and the surface of the inspection object W are arranged so as to be positioned at the same plane height position. Laser beams are emitted from the laser pointers 3 and 4 toward the surface of the stationary member 11 and the surface of the stationary member 12 , and the reflected laser beam is received by the light receiver 5 .

The stationary member 11 and the stationary member 12 of the surface inspection apparatus 10A according to Modification 1 correspond to the irradiation object of the surface inspection apparatus according to the present invention. The object to be irradiated may be a member other than the stationary member 11 and the stationary member 12, for example, a reflective member having a smooth surface and reflecting light.

With this configuration, the surface inspection apparatus 10A according to Modification 1 can detect defects in the inspection object W, and can accurately determine the optical axis deviation of the light receiver 5 with respect to the inspection object W. effect is obtained.

In the surface inspection apparatus 10A, each surface of the stationary member 11 and the stationary member 12 is arranged within the visual field area of the light receiver and outside the area of the inspection object W, and each surface of the stationary member 11 and the stationary member 12 is arranged. Since the surface is irradiated with the laser beams from the laser pointers 3 and 4, respectively, the effect is obtained that the laser beams can be irradiated onto the stable surface with little variation. The surface inspection apparatus 10A can be used during the operation of the production line, and can determine the optical axis deviation of the light receiver 5 without interfering with the so-called online inspection for inspecting the inspection object W. The deviation of the optical axis of the device 5 can be discovered at an early stage.

(Modification 2)
A surface inspection apparatus 10B according to Modification 2 will be described below with reference to the drawings.
As shown in FIGS. 9(1) and 9(2), the surface inspection apparatus 10B according to Modification 2 includes a pass roll 1, a pass roll 1A having the same configuration as the pass roll 1, a light source 2, and laser pointers 3 and 4. , stationary members 11 and 12 as irradiation objects, a light receiver 5, a signal processing section, and a display section. Like the surface inspection apparatus 10 according to the embodiment, the surface inspection apparatus 10B has a configuration for detecting defects in the inspection object F, determining optical axis deviation of the light receiver 5, and displaying the result on the display unit. ing.

The inspection object F is made of a transparent or translucent material such as a film, and has the property of transmitting inspection light emitted from the light source 2 . Therefore, not only defects on the surface of the inspection object F, but also internal defects such as air bubbles and perforations can be inspected.

The inspection object F of the surface inspection apparatus 10B according to Modification 2 is conveyed by pass rolls 1 and 1A. The light source 2 is arranged on the side opposite to the light receiver 5 with the transported inspection object F interposed therebetween, and irradiates the inspection light toward the back surface of the inspection object F. As shown in FIG. Irradiation of the inspection light is performed on the inspection object F located in the line perpendicular to the conveying direction, which is between the pass rolls 1 and the pass rolls 1A in the conveying direction. The inspection light passes through the inspection object F, that is, passes through and is received by the light receiver 5 .

The stationary member 11 is arranged in a direction orthogonal to the conveying direction of the inspection object F and at a position separated from the one side end F1 of the inspection object F in the width direction of the inspection object F, It is fixed to a fixing member (not shown). As with the stationary member 11, the stationary member 12 is located in a direction orthogonal to the conveying direction of the inspection object F and is separated from the other side end F2 of the inspection object F in the width direction of the inspection object F. and fixed to a fixing member (not shown). The stationary member 11 and the stationary member 12 are positioned so that a straight line connecting the center of the surface of the stationary member 11 and the center of the surface of the stationary member 12 overlaps a line L perpendicular to the conveying direction.

The surface of the stationary member 11, the surface of the stationary member 12, and the surface of the inspection object F are arranged so as to be positioned at the same plane height. Laser beams are emitted from the laser pointers 3 and 4 toward the surface of the stationary member 11 and the surface of the stationary member 12 , and the reflected laser beam is received by the light receiver 5 . Stationary member 11 and stationary member 12 are positioned within the field of view of the receiver and outside the area of the object F to be inspected.

With this configuration, the surface inspection apparatus 10B according to Modification 2 can obtain the same effects as the surface inspection apparatus 10 according to the embodiment. That is, the surface inspection apparatus 10B can detect defects in the inspection object F even if the inspection object F is a transparent or translucent web, and can detect optical axis misalignment of the light receiver 5 with respect to the inspection object F. can be accurately determined.

In the surface inspection apparatus 10B, the surfaces of the stationary member 11 and the stationary member 12 are arranged within the visual field area of the light receiver and outside the area of the inspection object F, and each surface of the stationary member 11 and the stationary member 12 is arranged. Since the surface is irradiated with the laser beams from the laser pointers 3 and 4, respectively, the effect is obtained that the laser beams can be irradiated onto the stable surface with little variation. The surface inspection apparatus 10B can also be used during the operation of the manufacturing line, and can determine the optical axis deviation of the light receiver 5 without interfering with the so-called online inspection for inspecting the inspection object F. The deviation of the optical axis of the device 5 can be discovered at an early stage.

Although the embodiments of the present invention have been described in detail above, the present invention is not limited to the above-described embodiments, and various designs can be made without departing from the scope of the invention described in the claims. Changes can be made.

1, 1A pass roll (irradiation target, stationary member, roller member)
1a, F1, W1 one side end (one end side in the direction orthogonal to the conveying direction of the inspection object)
1b, F2, W2 Other side end (side of the other end in the direction orthogonal to the conveying direction of the inspection object)
2 light source 3, 4 laser pointer (laser)
5 Light receiver 6 Signal processing unit 7 Display unit 10, 10A, 10B Surface inspection devices 11, 12 Stationary members 11a, 12a Surface CS Optical axes F, W of light receiver Object to be inspected J Path roll axis LS Optical axis of laser pointer SA Receiver viewing area T1 One side end (end of receiver viewing area)
T2 other side end (end of the viewing area of the receiver)

Claims (7)

A light source irradiates an inspection object conveyed on a web with inspection light, the inspection light passing through the inspection object is received by a light receiver, and defects in the inspection object are detected based on the output signal of the light receiver. A surface inspection device that
irradiating a laser beam from a laser onto an object to be irradiated, which is positioned within the field of view of the light receiver and outside the region of the object to be inspected;
Receive the laser reflected light reflected by the irradiation object with the light receiver,
1. A surface inspection apparatus, wherein an optical axis deviation of said light receiver with respect to said inspection object is determined based on said laser reflected light received by said light receiver. 2. The surface according to claim 1, wherein the deviation amount of the optical axis deviation is calculated based on at least one of the position, width, and intensity of the laser reflected light on the reflecting surface of the irradiation object. inspection equipment. 3. The surface inspection apparatus according to claim 2, wherein the position of said laser reflected light is measured with reference to the edge of said visual field area of said light receiver. At least one laser for irradiating the laser beam is provided on one end side in a direction perpendicular to the conveying direction of the inspection object, and at least one laser is provided on the other end side in the direction perpendicular to the conveying direction. 4. The surface inspection apparatus according to any one of claims 1 to 3, characterized by: 5. The surface inspection apparatus according to claim 1, wherein the object to be irradiated is either a stationary member or a roller member that conveys the object to be inspected as a web. 2. A surface of the irradiation object irradiated with the laser light and a surface of the inspection object irradiated with the inspection light are arranged at the same plane height position. The surface inspection device according to claim 5. Illuminator having a light source for irradiating inspection light onto a web-conveyed inspection object and arranged within a field of view area of a light receiver for receiving inspection light that has passed through said inspection object and outside the area of said inspection object an irradiation step of irradiating an object with a laser beam from a laser;
a light receiving step of receiving, by the light receiver, the inspection light that has passed through the inspection object and the laser reflected light that has been reflected by the irradiation object;
a determination step of detecting a defect of the inspection object based on the inspection light received by the light receiver and determining an optical axis deviation of the light receiver with respect to the inspection object based on the laser reflected light;
A surface inspection method comprising:

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