JP4694914B2 - Surface inspection method and apparatus - Google Patents

Description

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

  Conventionally, a substrate for a photosensitive drum or the like that requires high surface accuracy has been subjected to surface inspection in order to detect surface defects such as scratches, unevenness, foreign matter adhesion, and dirt.

  As such a surface inspection method, for example, the following Patent Document 1 proposes a method for improving the detection accuracy of surface defects by reducing the amount of specular reflection using illumination with stripe-like light and darkness. .

  Further, in Patent Document 2 below, a method for evaluating surface defects based on the distortion of a checker pattern obtained by illuminating a subject with a fine checker pattern and photographing the reflected light, and the degree of change in brightness between a bright part and a dark part Has been proposed.

Further, in Patent Document 3 below, high-frequency component image data and low-frequency component image data are created from image data obtained by photographing an inspection object, and both are used to form a processing mark and other scratches, nests, dirt, etc. A method for discriminating between the two has been proposed.
JP-A-5-52766 JP 2001-21332 A JP 2003-329605 A

  By the way, surface defects caused by various causes may not be detected unless the optical conditions such as the positional relationship between the light source and the camera are set within a very narrow range depending on the shape and size. For this reason, in various conventional surface inspection methods, there is a possibility that defects that show only a slight change under the optical conditions at the time of inspection cannot be detected and flow out.

  Conversely, depending on the type of defect, there is a case where it is not necessary to treat it as a defect, for example, it is eliminated by a surface treatment performed in a process after inspection. However, in the conventional surface inspection method, since the type of the defect cannot be discriminated, if there is a defect, it has to be a defective product regardless of the type, and the yield may be reduced.

  The present invention has been made in view of the above problems, and an object of the present invention is to provide a surface inspection method and apparatus that can determine the type of defect.

The present invention provides the following means. That is,
[1] A surface inspection method for detecting surface defects by irradiating illumination light to an inspection target region and detecting the reflected light with a camera,
For each part of the inspection target area, if there is no surface defect, there are a plurality of types including an optical condition that becomes a bright area where reflected light of illumination light is detected by the camera, and an optical condition that becomes a dark area where no reflected light is detected Detect surface defects under optical conditions,
A surface inspection method comprising: determining a type of a detected surface defect based on a combination pattern of presence / absence of defect detection under each optical condition.

  [2] The surface inspection method according to item 2, wherein the formation positions of the bright region and the dark region are moved.

  [3] The surface inspection method according to item 1 or 2, wherein the bright region and the dark region are formed simultaneously.

  [4] The surface inspection method according to item 3, wherein the plurality of optical conditions include an optical condition that is a boundary region between the bright region and the dark region.

  [5] The surface inspection method according to any one of the above items 1 to 4, wherein the dark region is formed by blocking illumination light applied to the region to be inspected by a light shielding body.

  [6] The slit body formed such that the plurality of light transmitting portions and the light shielding portions are alternately repeated alternately interrupts the illumination light applied to the inspection target region, so that a plurality of the above-described portions are formed on the inspection target region. 5. The surface inspection method according to any one of items 1 to 4, wherein the bright region and the dark region are alternately and repeatedly formed.

  [7] The surface inspection method according to any one of 1 to 6 above, in which surface defects are detected a plurality of times for at least one of a plurality of optical conditions.

[8] A surface inspection method for detecting surface defects by irradiating the outer peripheral surface of a tubular body with illumination light and detecting the reflected light with a camera,
In the detection area of the camera along the axial direction of the tubular body, if there is no surface defect, a bright area where the reflected light of the illumination light is detected by the camera and a dark area where the reflected light is not detected are alternately repeated,
While the tube body is rotated around the axis, the formation position of the bright region and the dark region is moved in the axial direction of the tube body, and the outer peripheral surface of the tube body is continuously photographed by the camera while the tube body is rotated a plurality of times. Thereby, for each part of the outer peripheral surface of the tubular body, the defect detection under a plurality of optical conditions including the optical region that is the bright region, the dark region, and the boundary region between the bright region and the dark region is performed,
A method for inspecting a surface of a tubular body, comprising: determining a type of a detected surface defect based on a combination pattern of presence / absence of defect detection under each optical condition.

  [9] The light region and the dark region are alternately switched by intermittently blocking the illumination light applied to the tube body by the slit body formed so that the plurality of light transmitting portions and the light shielding portions are alternately repeated. 9. The surface inspection method according to 8 above, wherein the method is repeatedly formed.

  [10] The surface inspection method according to the above item 8 or 9, wherein a detection area by the camera is moved in the axial direction of the tubular body together with the bright area and the dark area.

  [11] The surface inspection method according to any one of items 8 to 10, wherein the tube is a photosensitive drum substrate.

[12] A step of forming an article for which surface accuracy is required;
A surface inspection step for performing the surface inspection method according to any one of the preceding items 1 to 11 as the inspection object,
Determining the article according to whether or not the type of defect determined by the surface inspection process satisfies a predetermined criterion, and determining the article as a finished product when the predetermined criterion is satisfied;
A method for producing an article, comprising:

  [13] A photosensitive drum substrate manufactured by the method for manufacturing an article according to item 12 above.

[14] A surface inspection apparatus for detecting surface defects by irradiating an inspection target region with illumination light and detecting the reflected light with a camera,
An illumination system capable of forming a bright area in which reflected light of illumination light is detected by the camera and a dark area in which reflected light is not detected if there is no surface defect for each part of the inspection target area,
Under a plurality of optical conditions, including an optical condition that becomes a bright area and an optical condition that becomes a dark area with respect to each part of the inspection target area by the camera while changing the formation position of the bright area and the dark area by the illumination system Control means for performing defect detection;
Based on the combination pattern of the presence or absence of defect detection under each optical condition, determination means for determining the type of detected surface defects,
A surface inspection apparatus comprising:

[15] Molding means for molding an article for which surface accuracy is required;
The surface inspection apparatus according to item 14, wherein the article is an inspection target;
Discriminating the article according to whether or not the type of surface defect determined by the surface inspection apparatus satisfies a predetermined standard, and when the predetermined standard is satisfied, a determination unit that makes the article a finished product,
A manufacturing system characterized by comprising:

[16] A surface inspection apparatus for detecting a surface defect of a tubular body,
Illumination for illuminating the outer peripheral surface of the tube with illumination light;
A camera that detects the reflected light of the illumination light in the detection region along the axial direction of the tubular body;
A plurality of light-transmitting portions and light-shielding portions are alternately formed, and the illumination light is intermittently blocked in the axial direction of the tube, so that the reflected light of the illumination light is detected by the camera if there is no surface defect. A slit body that alternately and repeatedly forms a bright area and a dark area in which reflected light is not detected;
While rotating the tube body around the axis, the slit body is moved in the axial direction of the tube body, and while the tube body is rotated a plurality of times, the outer peripheral surface of the tube body is continuously photographed by the camera. Control means for performing defect detection under a plurality of optical conditions, including optical conditions that are the bright region, the dark region, and a boundary region between the bright region and the dark region, for each part of the outer peripheral surface;
Based on the combination pattern of the presence or absence of defect detection under each optical condition, determination means for determining the type of detected surface defects,
A surface inspection apparatus for a tubular body, comprising:

[17] Molding means for molding a tubular body that requires surface accuracy;
The surface inspection apparatus according to 16 above, wherein the tubular body is an inspection object;
Classifying the tube according to whether or not the type of surface defect determined by the surface inspection apparatus satisfies a predetermined criterion, and a discriminating means that makes the tube a finished product when the predetermined criterion is satisfied;
A tubular body manufacturing system comprising:

  According to the above invention [1], in order to detect surface defects under a plurality of types of optical conditions, and to determine the type of detected surface defects based on the combination pattern of the presence or absence of defect detection under each optical condition, Various defects existing in the inspection target area can be found under any optical condition, and the types of surface defects are determined by the combination of the optical conditions under which each detected defect is detected and the optical conditions that are not detected. Can be determined.

  According to the invention [2], since the formation positions of the bright region and the dark region are moved, it is possible to sequentially detect surface defects under the optical conditions of the bright region and the dark region over the entire region to be inspected.

  According to the invention [3], since the bright region and the dark region are formed at the same time, the defect detection in the bright region and the defect detection in the dark region can be simultaneously performed at each part in the inspection target region.

  According to the above invention [4], since the optical condition that is the boundary region between the bright region and the dark region is included, various types of defects can be detected more reliably, and the types of the detected defects can be more accurately determined. be able to.

  According to the invention [5], since the dark region is formed by blocking the illumination light irradiated to the inspection target region by the light shielding body, the dark region can be easily formed.

  According to the above invention [6], since the slit light formed so that the plurality of light transmitting portions and the light shielding portions are alternately repeated, the illumination light irradiated to the inspection target region is intermittently blocked. A plurality of bright regions and dark regions can be easily formed.

  According to the above invention [7], the surface defect is detected a plurality of times for at least one of the plurality of optical conditions, so that it is possible to reduce the detection omission and more accurately determine the type of the defect.

  According to the invention [8], while the tube is rotated about the axis, the formation position of the bright region and the dark region is moved in the axial direction of the tube, and the outer periphery of the tube is rotated by the camera while the tube rotates a plurality of times. Since the surface is continuously photographed, a plurality of optical conditions can be continuously formed for each part of the outer peripheral surface of the tubular body, and a plurality of optical conditions including a light region, a dark region, and a boundary region are included. In order to detect defects under optical conditions and determine the type of detected surface defects based on the combination pattern of presence / absence of defect detection under each optical condition, any of the various defects present on the outer peripheral surface is selected. It is possible to more accurately determine the type of surface defect based on the combination pattern of the optical condition in which each detected defect is detected and the optical condition in which each detected defect is detected more reliably under optical conditions.

  According to the above invention [9], the slit body formed so that the plurality of light transmitting portions and the light shielding portions are alternately repeated intermittently blocks the illumination light applied to the tube body. It can be easily formed with a dark region.

  According to the invention [10], since the detection area by the camera is moved in the axial direction of the tubular body together with the bright area and the dark area, the formation position of each optical condition in the field of view of the camera does not change and more accurately. The type of the surface defect can be detected and determined.

  According to the invention [11], it is possible to accurately evaluate the surface condition required for the photosensitive drum substrate and contribute to the production of a suitable photosensitive drum substrate.

  According to the above invention [12], an article having a defect that does not need to be treated as a defect while preventing the outflow of a defective product, because the molded article is discriminated by the type of the defect determined by any one of the above surface inspection methods. It is possible to prevent a situation in which the yield is reduced as a defective product.

  According to the invention [13], it is possible to secure a photosensitive drum substrate that satisfies a predetermined standard for surface defects.

  According to the above invention [14], in order to detect surface defects under a plurality of types of optical conditions, and to determine the type of detected surface defects based on the combination pattern of the presence or absence of defect detection under each optical condition, Various defects existing in the inspection target area can be found under any optical condition, and the types of surface defects are determined by the combination of the optical conditions under which each detected defect is detected and the optical conditions that are not detected. Can be determined.

  According to the above invention [15], an article having a defect that does not need to be treated as a defect while preventing the outflow of a defective product because the molded article is discriminated by the type of defect determined by any one of the above surface inspection methods. It is possible to prevent a situation in which the yield is reduced as a defective product.

  According to the invention [16], while the tube is rotated about the axis, the formation position of the bright region and the dark region is moved in the axial direction of the tube, and the outer periphery of the tube is rotated by the camera while the tube rotates a plurality of times. Since the surface is continuously photographed, a plurality of optical conditions can be continuously formed for each part of the outer peripheral surface of the tubular body, and a plurality of optical conditions including a light region, a dark region, and a boundary region are included. In order to detect defects under optical conditions and determine the type of detected surface defects based on the combination pattern of presence / absence of defect detection under each optical condition, any of the various defects present on the outer peripheral surface is selected. It is possible to more accurately determine the type of surface defect based on the combination pattern of the optical condition in which each detected defect is detected and the optical condition in which each detected defect is detected more reliably under optical conditions.

  According to the invention [17], since the formed tubular body is discriminated by the type of the defect determined by any one of the surface inspection methods, it has a defect that does not need to be handled as a defect while preventing the outflow of a defective product. It is possible to prevent a situation in which the yield of the tubular body is reduced as a defective product.

[First Embodiment]
A first embodiment of the present invention will be described with reference to schematic explanatory diagrams.

  FIG. 1 is a perspective view of a cylindrical body (tubular body) as an inspection object of the surface inspection apparatus (cylindrical body inspection apparatus) according to the first embodiment.

<Inspection object>
As shown in FIG. 1, a cylindrical body (tubing body) 90 is a photosensitive drum, a transfer roller, a developing roller, and other parts in a copying machine, a printer, a FAX machine, and a multi-function machine constituting an electrophotographic system. The outer peripheral surface 91 is used as an inspection target region for surface inspection.

  Specific examples of such a cylindrical body 90 include an element tube and a substrate for a photosensitive drum in a copying machine, a printer, or the like that employs an electrophotographic system. The substrate for the photosensitive drum is a cylindrical body that has been subjected to cutting, drawing, or the like, and is a cylindrical body before the formation of the photosensitive layer. Further, the cylindrical body after the photosensitive layer is formed on the photosensitive drum substrate can also be a cylindrical body to be subjected to the inspection of the present invention. The inspection target area 91 on the outer peripheral surface of the photosensitive drum substrate has a metallic luster and is a mirror surface that regularly reflects most of the incident light.

  The substrate for a photosensitive drum to be inspected by the surface inspection apparatus has a diameter of about 10 to 60 mm and a length of about 200 to 500 mm, for example.

  As a manufacturing method of such a cylindrical body 90, a combination of extrusion molding and pultrusion molding can be mentioned as described later. However, the method is not limited to this, and any method can be used as long as the cylindrical body can be piped, such as extrusion molding, pultrusion molding, casting, forging, injection molding, cutting, or a combination thereof.

  The material of the target cylindrical body 90 is not particularly limited, and various types of metal materials, synthetic resins, and the like can be applied. For example, aluminum and aluminum alloys (1000 to 7000 series), copper and copper alloys, steel materials, magnesium and magnesium alloys can be mentioned.

  Examples of particularly preferable materials include aluminum alloys 3003, 6061, 6051, and 7075. For example, 3003 alloy can be preferably used as a substrate for a photosensitive drum, 6061 alloy can be preferably used as a propeller shaft which is an automobile part, 6051 alloy can be preferably used as a general mechanical part, and 7075 alloy is Preferably it can be used as a bat tube. In addition, “aluminum” in this specification includes an aluminum alloy.

<Overall configuration>
FIG. 2 is a front view of the surface inspection apparatus according to the first embodiment of the present invention. FIG. 3 is a plan view of the apparatus. FIG. 4 is a side view of the apparatus.

  As shown in FIG. 2, the surface inspection apparatus 1 performs overall control of an illumination (light source) 10, a light shielding body 20, a camera 30, a chuck unit 70 that supports a cylindrical body (inspection object) 90 at an inspection position, and each unit. The inspection apparatus main body 2 including the management computer 80 and the like, the cylindrical body supply conveyor 51 that supplies the cylindrical body 90 to the inspection apparatus main body 2, the acceptable product unloading conveyor 52 that sequentially unloads the cylindrical body 90 from the inspection apparatus main body 2, and the And an acceptable product carry-out conveyor 53.

  The management computer 80 includes a CPU, a memory such as a RAM and a ROM, a hard disk storage device, an input / output unit, a personal computer provided with an interface with each unit, and the like. Functionally, an image captured by the camera 30 is displayed. Image processing means for processing, control means for controlling driving of each part, and further, as will be described later, determination means for determining the type of surface defect, and determination means for determining pass / fail of the inspected tube (cylindrical body). Yes.

  The cylindrical body supply conveyor 51 supports the vicinity of both ends of each cylindrical body 90 with a cylindrical body support base 59 having an upper edge cut into a V shape, and each cylindrical body support base 59 is not illustrated with a drive chain (not shown). The cylindrical body 90 before the inspection is transferred to the inspection apparatus main body 2 by moving the inspection body.

  On the cylindrical body supply side (the left side in FIGS. 2 and 3) of the inspection apparatus main body 2, an inter-conveyor transfer device 54 that lifts and transfers the cylindrical body 90 from both side ends is provided. The cylindrical body 90 transported by the conveyor 51 is transferred to the transport conveyor 61 in the inspection apparatus main body 2 by the inter-conveyor transfer device 54.

  Both the accepted product carry-out conveyor 52 and the rejected product carry-out conveyor 53 support the vicinity of both ends of each cylindrical body 90 with cylindrical support bases 59 having upper edges cut into V-shapes. The cylindrical body 90 after inspection is carried out of the inspection apparatus main body 2 by moving the support bases 59 with a drive chain (not shown). Further, an unacceptable item delivery robot 56 is provided at a position across the acceptable item unloading conveyor 52 and the unacceptable item unloading conveyor 53. The undelivered product delivery conveyor 53 is fed out from the accepted product delivery conveyor 52.

  On the cylinder carrying-out side (right side in FIGS. 2 and 3) of the inspection apparatus body 2, an inter-conveyor transfer device 55 that lifts and transfers the cylindrical body 90 from both side ends is provided. The cylindrical body 90 on the transport conveyor 62 in 2 is transferred to the accepted product delivery conveyor 52 by the inter-conveyor transfer device 55.

  The conveyors 61 and 62 in the inspection apparatus main body 2 support the vicinity of both ends of each cylindrical body 90 with cylindrical support bases 63 having upper edges cut into V-shapes, and each cylindrical support base 63. Are moved by the drive chain, thereby transferring the cylindrical body 90 immediately before and immediately after the inspection.

<Rotary transfer device>
A rotary transfer device 64 that transfers the cylindrical body 90 to the inspection position B is disposed between the conveyors 61 and 62 before and after the inspection. The rotary transfer device 64 includes a plurality of (here, four) chuck portions 70 that support the cylindrical body 90.

  Each chuck portion 70 is attached to a rotary frame 67 connected to a rotary shaft 66 of a rotation drive motor 65, and an extraction position A for taking out the cylindrical body 90 from the conveyor 61, the light source 10, the light shielding body 20, and the like. The chuck portions 70... Are located at the same time at an inspection position B where inspection by an inspection optical system such as the camera 30 is performed and a delivery position C where the cylindrical body 90 is sent to the transport conveyor 62.

  The chuck unit 70 located at the take-out position A chucks and takes out the cylindrical body 90 before inspection from the transport conveyor 61, and the chuck unit 70 located at the inspection position B rotates and supports the cylindrical body 90 to perform surface inspection. The chuck portion 70 located at the delivery position C can simultaneously perform the work of releasing the chuck of the cylindrical body 90 after inspection and sending it to the transport conveyor 62. Further, the chuck portion 70 that moves from the take-out position A to the inspection position B starts to rotate the cylindrical body 90 in advance so that the rotation of the cylindrical body 90 is stabilized before the chuck portion 70 is conveyed to the inspection position B. As a result, when the inspection position C is reached, the surface inspection is immediately performed, and the cycle time can be shortened.

<Chuck part>
FIG. 5 is a front view of the chuck portion 70 according to the first embodiment. FIG. 6 is a side view of the chuck portion 70.

  As shown in these drawings, each chuck portion 70 includes one reference roller 71 and two support rollers 72 and 72, and a pair of chuck portions 70 and 70 disposed on both sides of the cylindrical body 90. Cooperate to chuck one cylindrical body 90.

  In the posture at the inspection position B, the reference roller 71 in each chuck portion 70 is in contact with the upper side of the inner peripheral surface of the cylindrical body 90 and defines its height position. The reference roller 71 is rotatably attached to the chuck portion main body 76, and rotates together with the cylindrical body 90 when performing inspection. In addition, a reference roller rotation drive motor 73 is provided on one of the pair of chuck portions 70 that cooperate to chuck one cylindrical body 90, and the reference roller 71 is driven to rotate at the time of inspection. 90 can be rotated.

  In the posture at the inspection position B, the support rollers 72 and 72 are respectively in contact with the lower left and right sides of the inner peripheral surface of the cylindrical body 90 and urge the cylindrical body 90 downward by air driving pressure. The upper side of the inner peripheral surface is reliably brought into contact with the reference roller 71 to stabilize the height position. Further, the support rollers 72 and 72 are rotatably attached to the chuck portion main body 76, and rotate together with the cylindrical body 90 when the inspection is executed. Further, as shown by the broken line and the solid line in FIGS. 5 and 6, the support rollers 72, 72 are moved in the vertical direction in the posture at the inspection position B, so that the distance from the reference roller 71 is set to the inner diameter of the cylindrical body 90. The cylindrical roller 90 can be inserted into the cylindrical body 90 together with the reference roller 71 before and after chucking the cylindrical body 90. For these operations, each chuck unit 70 is provided with a support roller driving unit 74 that moves the support rollers 72 and 72 up and down by air driving pressure.

  The chuck body 76 to which the reference roller 71 and the support rollers 72 and 72 are attached is moved in the axial direction of the cylindrical body 90 by the slide drive portion 75 with respect to the chuck portion base 77 attached to the rotary frame 67 of the rotary transfer device 64. The sliding operation is possible, and the cylindrical body 90 can be sandwiched from both outer sides and chucked.

  The rotary transfer device 64 and the chuck portion 70 constitute a support portion that supports the cylindrical body 90 so as to be rotatable at a predetermined inspection position B.

<Lighting (light source)>
The illumination (light source) 10 irradiates the outer surface of the cylindrical body 90 conveyed to the inspection position B with illumination light for inspection. The illumination 10 is composed of a linear light source such as a fluorescent lamp capable of obtaining high brightness, and has an extension along the longitudinal direction of the cylindrical body 90. As shown in FIG. 2, the illumination 10 is disposed almost directly above the cylindrical body 90 at the inspection position B by the light source support frame 13, and effectively directs the light to be irradiated toward the cylindrical body 90. The hood 12 covers other than the lower part.

  The illumination 10 includes a light source that has a predetermined spread and that emits diffused light.

  Diffused light refers to light that is diffused and irradiated in various directions from a light source. In addition, parallel light is mentioned as light which is not diffused light. Parallel light refers to light emitted from a light source that is collected using, for example, a lens or fiber, and is irradiated as a bundle of light with directionality.

  The phrase “the light source of the illumination 10 has a predetermined spread” means that the light source is not a point light source but a portion that emits diffused light has a certain area.

  If the illumination 10 that has such a predetermined spread and irradiates diffused light is used, light in various directions enters each part of the surface of the cylindrical body 90 from each part of the illumination 10.

<Shading body>
The light shielding body 20 shields part of the light emitted from the light source 10 and forms bright and dark stripes on the outer peripheral surface 91 of the cylindrical body 90 to constitute various different optical conditions. The light blocking body 20 functions as an illumination system together with the illumination 10.

  FIG. 7 is a perspective view of the light blocking body 20 in the first embodiment. As shown in FIG. 7, the light shielding body 20 of the first embodiment is configured by a slit body formed such that a plurality of slit hole-like light transmitting portions 23... And light shielding portions 24. Yes.

  The sizes of the light transmitting part 23 and the light shielding part 24 can be appropriately set. For example, the width (opening width) a of the light transmitting part 23 is about 1 to 6 mm, and the width of the light shielding part 24 is about 3 to 6 mm. Is preferred.

  As shown in FIGS. 2 to 4, the light shield 20 is attached to the light shield support base 25 and is permanently disposed between the illumination 10 and the cylindrical body 90 at the inspection position B.

  When the cylindrical body 90 is illuminated by the illumination 10 that has a predetermined spread and irradiates diffused light through the light-shielding body (slit body) 20 in which the light-transmitting portions 23 and the light-shielding portions 24 are formed, the cylinder 90 is illuminated. On the surface of the body 90, the amount of light shielded by the light shielding portions 24 differs depending on the part, so that light and dark stripes in which the amount of light reached continuously changes are formed.

<Camera>
The camera 30 includes a line sensor 32 in which a large number of light quantity detection elements are arranged one-dimensionally, a lens that forms an image of a predetermined detection region 31 extending in the axial direction of the cylindrical body 90 on the line sensor 32, and the like. It is configured as a line sensor camera, and detects the amount of light incident from each part of the detection region 31.

  In general, a line sensor is a sensor in which photosensitive portions that receive light are arranged in a single line, and has a great feature that the number of pixels in one line can be increased as compared with an area (two-dimensional) sensor. In the area sensor, the number of pixels in the horizontal direction is, for example, about 1000 pixels even for high-definition TV, but in the line sensor, the number of pixels of 1000 to 7500 pixels can be easily realized. Sensors that exceed this level have also appeared, and high resolution can be obtained easily and inexpensively. Further, by using a line sensor, it is possible to sequentially process images as compared to an area sensor, and there is an advantage that a higher-speed inspection can be realized.

  The line sensor 32 only needs to be capable of detecting one-dimensional light amount information. Even if it is a single line black and white line sensor, for example, a color line sensor in which sensors for each color such as RGB are arranged in a total of three lines, or A color line sensor in which sensors for respective colors are alternately arranged may be used. Furthermore, a TDI line sensor in which a plurality of rows of sensors are arranged in a direction perpendicular to the main arrangement direction of the line sensors may be used. Alternatively, it may be a partial scan camera or the like that is substantially used as a line sensor by selectively using only one or a plurality of specific rows of sensors that are two-dimensionally arranged.

  This camera 30 is attached to a camera support base 34 whose position and angle can be finely adjusted, and aims at a predetermined area extending in the axial direction as the detection area 31 in the outer peripheral surface 91 of the cylindrical body 90 at the inspection position B. Yes.

<Slide table>
The light-shielding body support base 25 to which the light-shielding body 20 is attached and the camera support base 34 to which the camera 30 is attached are both mounted on the slide table 40 and can be slid in the axial direction of the cylindrical body 90 at the inspection position B. Yes. That is, the slide table 40 is supported by a slide roller 41 so as to be slidable on a slide table support 42 fixed to the main body frame, and is slid by a slide drive motor 43.

  The stroke of this slide driving operation is set to be larger than the sum of the width a of the light transmitting portion 23 of the light shielding body 20 and the width b of the light shielding portion 24. Specifically, for example, about 1.1 times or more of the sum of the width a of the light transmitting portion 23 and the width b of the light shielding portion 24 is preferable. As a result, a case where the entire axial position of the inspection target region 91 on the outer peripheral surface of the cylindrical body 90 is located immediately below the light transmitting portion 23 and the light shielding portion 24 of the light shielding body 20 is realized.

<Principle of surface inspection>
FIG. 8 is a side view illustrating an outline of a main part of the surface inspection apparatus for the cylindrical body 90 according to the first embodiment. FIG. 9 is a perspective view of the same.

  As shown in FIG. 8, according to the curvature of the cylindrical body 90, the camera 30 regularly reflects light that is incident on the inspection target area 91 on the outer peripheral surface of the cylindrical body 90 from the light source 10 unless the light shielding body 20 exists. It is arrange | positioned in the position which light-receives.

  Further, the detection region 31 by the camera 30 is a portion on the outer peripheral surface 91 side facing the portion where the inner peripheral surface side of the cylindrical body 90 is supported by the reference roller 71. This portion is the portion where the position and angle are most stable because each portion of the cylindrical body 90 is supported by the reference roller 71. Therefore, it is possible to reduce the influence on the result of the surface inspection due to the shape accuracy such as the bending of the cylindrical body 90.

  Further, since the detection region 31 by the camera 30 is a portion facing the reference roller 71, even the cylindrical bodies 90 having different sizes (diameters) can constitute substantially the same optical conditions. In particular, if the cylindrical body 90 has the same thickness, the detection region 31 can be configured with substantially the same optical conditions. Therefore, even when the surface inspection of the cylindrical body 90 of various sizes is performed, it is possible to efficiently perform the surface inspection while minimizing the labor and time required for the setup change.

  Further, since the cylindrical body 90 is supported from the inner peripheral surface side, it is possible to reduce adverse effects on the surface inspection such as the reference roller 71 and the like causing a shadow on the outer peripheral surface 91 of the cylindrical body 90.

  Moreover, as shown in FIG. 9, since the light source 10 has an extension in the axial direction of the cylindrical body 90 and emits light of various angles downward, each part of the inspection target region on the outer peripheral surface 91 of the cylindrical body 90 Although light of various angles that have passed through the light transmitting portion 23 of the light shielding body 20 is incident on the light, the angle of the incident light is limited by the light shielding portions 24 of the light shielding body 20.

  FIG. 10 is an explanatory diagram of the optical conditions of each part of the inspection target region viewed from the camera. FIG. 11 is an explanatory diagram of various optical conditions in an image photographed by the camera. As shown in FIG. 10, when viewed from the camera 30, the detection region 31 of the camera 30 includes a bright region (regular reflection light region) 28 in which regular reflection light incident on the camera 30 exists, and a normal region. A dark region (regular reflection light limiting region) 29 in which no reflected light exists is formed. Further, the detection area 31 includes a boundary area (edge area) 27 at the boundary between the bright area 28 and the dark area 29.

  In the bright region 28, specularly reflected light is incident on the camera 30 if there is no surface defect. However, if there is a surface defect, the reflection angle changes and the camera 30 cannot capture it. For this reason, when the surface defect is in the bright region 28, it is often detected as a defect (black defect) darker than the surroundings. The surface defects detected as such black defects are often sharp defects or relatively deep defects that greatly change the reflection angle.

  Even in the bright region 28, if the detection gradation of the normal part is not saturated, a defect (white defect) brighter than the normal part may be detected.

  In the dark region 29, the regular reflection light does not enter the camera 30 if there is no surface defect. FIG. 12 is an explanatory diagram in the case where there is no surface defect in the dark region 29.

  As shown in FIG. 5A, when focusing on a specific target region 29 a in the dark region 29, the light 12 a that should be reflected by the target region 29 and enter the camera 30 as specularly reflected light is reflected by the light shielding unit 24. Shaded. Lights 12b and 12c from the light source 10 are incident on the target part 29a. If the target part 29a has no surface defects and is normal, the specularly reflected lights 13b and 13c of these lights 12b and 12c are obliquely directed. Opposite, it does not enter the camera as regular reflection light. Therefore, the region of interest 29a is dark when viewed from the camera.

  Specifically, as shown in the distribution diagram of received light amount in FIG. 12B, the received light amount of the camera 30 is small in the dark region 29, and regular light is incident on the bright region 28. Many are brighter. In the boundary region 27 between the bright region 28 and the dark region 29, the amount of received light continuously changes from the bright region 28 to the dark region 29 due to light diffraction or the like. In FIG. 12B, the alternate long and two short dashes line indicates the amount of light received when the light shield 24 is not provided.

  FIG. 13 is an explanatory diagram when a surface defect is present in the dark region 29.

  As shown in FIG. 6A, if the target portion 29a has a surface defect, the specularly reflected light of the lights 12b and 12c from the light source 10 may be directed right above the camera, depending on the shape. Here, the reflection direction of the light 12b incident on the region of interest 29a at an incident angle α is changed directly above. At this time, the region of interest 29a becomes brighter as viewed from the camera. Since this part 29a is originally in the dark region 29, there is no specular reflection light from the surrounding normal part, so that the specular reflection light due to the surface defect is regarded as an outstanding light quantity.

  Specifically, as shown in the distribution diagram of received light amount in FIG. 13B, in the dark region 29 including the region of interest 29a, the amount of received light detected by the camera is small if there is no surface defect. If specularly reflected light incident on the light is generated, it can be reliably captured as a change in the amount of light that stands out with respect to the surroundings in the received light amount distribution diagram. That is, the surface defect can be detected with high contrast without being buried in the regular reflection light of the surrounding normal part such as the bright region 28.

  Thus, when the surface defect is in the dark region 29, it is often detected as a defect (white defect) brighter than the surroundings. Such surface defects detected as white defects are often gradual defects or relatively shallow defects that change the reflection angle only slightly.

  Even in the dark region 29, a defect (black defect) that is darker than the normal part may be detected if the detection gradation of the normal part is not saturated.

  Since the boundary region 27 is located at the boundary between the bright region 28 and the dark region 29, it has the properties of both the bright region 28 and the dark region 29 described above, and both black defects and white defects are detected.

  As described above, when the optical conditions are roughly classified into the bright region 28, the dark region 29, and the boundary region 27, various surface defects are detected as defects depending on their sizes, depths, sharp shapes, or gentle shapes. There are optical conditions that are not detected.

  In this embodiment, whether or not a surface defect candidate detected under any optical condition is detected as a defect under other optical conditions, that is, a combination pattern of presence or absence of defect detection under each optical condition is determined. The type of the surface defect is determined based on this. A specific determination method will be described later.

  Although the optical conditions are broadly classified into the bright region 28, the dark region 29, and the boundary region 27, illumination that is limited by the light shielding unit 24 in the bright region 28 and the dark region 29 depending on the distance from the light shielding unit 24. Since the incident angle of light is different, various optical conditions are formed. Therefore, depending on the type of defect, even if it is in the same bright region or dark region, it may not be detected as a black defect.

  In this embodiment, as will be described later, the defect detection is performed a plurality of times with different optical conditions for the bright region 28 and the dark region 29, and each type of surface defect can be detected more reliably. It has become.

  Specifically, the surface inspection is performed by continuously imaging the outer peripheral surface 91 by the camera 30 with respect to the cylindrical body 90 which is sent to the inspection position B and rotated about the axis by the reference roller 70. Is called. Therefore, each circumferential position of the outer peripheral surface 91 of the cylindrical body 90 sequentially becomes the detection region 31 of the camera 30, and the entire region can be inspected.

  The rotational speed of the cylindrical body 90 is set according to the defect size to be detected and the line sensor capture speed of the camera 30. That is, the substantial width of the detection region 31 photographed by the camera 30 is determined according to the line sensor capture speed and the rotational speed of the cylindrical body 90 when the cylindrical body 90 is rotating. The substantial width of the detection area 31 is set to be smaller than the defect size to be detected.

  The specific surface defects to be detected depend on the resolution 30 of the camera, but various sizes and depths such as millimeter order, micron order, submicron order, etc. Faults can be detected.

  Further, while rotating the cylindrical body 90 in this way, the light shielding body 20 slides with a stroke larger than the sum of the width a of the light transmitting portion 23 and the width b of the light shielding portion 24 in the axial direction of the cylindrical body 90. Operate. For this reason, the entire outer peripheral surface 91 of the cylindrical body 90 is included in the detection region 31 of the camera 30 as the bright region 28 and the dark region 29 and the boundary region 27 thereof. Can be detected.

  FIG. 14 is an explanatory diagram of an image obtained by continuously photographing with a camera while rotating a cylindrical body. In this figure, each line in the horizontal axis direction indicates the brightness of the detection region 31 detected by the camera (line sensor) 30 at each moment, and imaging is repeated successively and sequentially while rotating the tube 90. The obtained images are arranged in the vertical axis direction.

  Since the camera 30 slides together with the light blocking body 20, the same optical conditions are always formed at the same position when viewed from the camera 30. For this reason, as will be described later, the surface defect can be reliably detected by simple image processing.

  The defect detection by the camera 30 is continuously performed while the cylindrical body is rotated a plurality of times (six rotations here). For this reason, each part on the outer peripheral surface 91 of the cylindrical body has different optical areas such as a bright area 28, a dark area 29, and a boundary area 27 while the cylindrical body 90 rotates a plurality of times and reaches the detection area 31 of the camera 30. Defect detection under conditions is performed. Further, since the rotation is performed six times here, the optical conditions in which the limit of the incident angle of the illumination light is different even in the bright region 28, or the boundary region 27 is limited as on the right side and the left side of the dark region 29. The optical conditions differ in the direction of the illumination light.

  Further, since the light shielding body 20 and the camera 30 move in the axial direction of the cylindrical body 90 while rotating the cylindrical body 90, the bright area 28 and the dark area 29 on the outer peripheral surface 91 of the cylindrical body 90, and the detection area of the camera 30. 31 moves spirally on the outer peripheral surface 91 of the cylindrical body 90. When this is viewed from the camera 30 side, each part of the cylindrical body 90 moves within the detection region 31 of the camera 30 for each round. Specifically, as shown in FIG. 14, if a part of the cylindrical body 90 appears at the position A1 in the first round in the captured image of the camera 30, the camera 30 per round in the second round. It appears at a position A2 that is shifted in the horizontal direction by the amount of slide, and thereafter appears at positions A3 to A6 that are also shifted in the horizontal direction for each circumference. Thereby, it can be seen that the surface of each part on the outer peripheral surface 91 of the cylindrical body 90 is surface-inspected under different optical conditions for each rotation of the cylindrical body 90 due to the movement of the light shielding body 20 and the camera 30.

  A series of operations for photographing a cylindrical body under a plurality of optical conditions by the camera 30 as described above is controlled and executed by the control means of the management computer 80.

  FIG. 15 is an explanatory diagram illustrating an example of an image processing process performed by an image processing unit of the management computer 80 in order to detect a surface defect from an image captured by a camera.

  FIG. 15A is an example of an image photographed by the camera 30 while rotating the cylindrical body 90.

  For the image thus obtained, first, in order to facilitate defect detection, weak signals in the dark region 29 and the boundary region 27 are emphasized by using image processing such as differentiation processing, integration processing, expansion processing, and contraction processing. The processing to do.

  Then, a difference process is performed to make the surface defect stand out from the stripe pattern formed by the bright area 28 and the dark area 29. FIG. 15B is an example of an image that has been subjected to difference processing. In this difference process, the difference between each line of data and the data at the same position of one or more previous lines is calculated, and the magnitude of the difference is expressed by shading.

  In this embodiment, as described above, the camera 30 moves in the axial direction of the tubular body 90 together with the light blocking body 20, so that the lateral positions of the bright region 28, the dark region 29, and the boundary region 27 are changed in the captured image. Absent. Thus, the difference process can be easily performed by obtaining the difference between the upper and lower sides of the captured image. Incidentally, when the light shield 20 and the camera 30 are not interlocked, the bright region 28 and the like extend in the oblique direction in the figure. Therefore, if the difference is obtained in the oblique direction in the photographed image according to the relative speed of the two. Good.

  A bright or dark defect candidate can be found from the captured image that has been subjected to the difference processing.

  In this way, defect candidates are detected. However, since defect detection is performed a plurality of times (here, six times) for the same part, the image processing means of the management computer 80 bundles the results detected for the same part. For each defect candidate site, the presence / absence of defect detection as to whether it was detected as a defect candidate or not detected under each optical condition of the bright region 28, dark region 29, and boundary region 27 is determined.

  In this embodiment, the defect detection is performed a plurality of times under the optical condition of becoming the bright region 28 for the same part, but if a defect is detected one or more times, it is a defect candidate detected in the bright region 28. Judge. This is because, even in the same bright region 28, a plurality of optical conditions having different incident angles of illumination light are configured, and defect candidates that are detected only in one of them are treated as defect candidates that can be detected in the bright region 28. The same applies to the dark area 29 and the boundary area 27.

  In this way, if the presence or absence of defect detection under each optical condition is obtained for the defect candidate at each part, the determination means of the management computer 80 determines the type of the defect candidate based on the combination pattern.

  Various defects have optical conditions that can be detected or optical conditions that cannot be detected depending on the type classified by shape, size (area), depth, and the like. Therefore, the bright region 28, the dark region 29, and the boundary region 27 are present. This is based on the fact that a certain relationship is recognized between the combination pattern of whether or not to be detected under various optical conditions such as the above and the type of defect.

  The determination means of the management computer 80 can determine the defect type of the surface defect (candidate) thus detected.

<Example of detection of surface defects>
FIG. 16 is an example of the relationship between the combination pattern of presence / absence of defect detection and the type of surface defect under each optical condition.

  For example, when defect detection is performed on the same region to be inspected under the optical conditions of the bright region 28, the dark region 29, and the boundary region (interference region) 27, an abnormality (surface defect) is detected in the bright region 28, for example. Then, it is assumed that no abnormality is detected in the boundary region (edge region) 27 and the dark region 29. In this case, it can be determined that the defect candidate is an abnormality detected in the bright region 28 but cannot be detected under the conditions of the boundary region 27 and the dark region 29.

  As described above, when the detection is performed in the bright region 28 and not detected in the boundary region (border region) 27 and the dark region 29, the relationship between the combination pattern of the detection result illustrated in FIG. 16 and the type of surface defect is obtained in advance. If so, it can be determined that the line is a large or extra large size shallow or deep sharp line scratch, or an extra large size or extremely deep (ultra deep) sharp line scratch.

  Further, in addition to the bright area 28, the boundary area (edge area) 27 is also detected, and if it is not detected only in the dark area 29, a sharp line flaw is detected when the boundary area 27 is not detected. It can be determined that the defect size is smaller than the line scratch and is about the medium size, and even if it is a sharp point scratch, the defect size is smaller than the point scratch when it is not detected in the boundary region 27, It can be determined that the size is large. In addition, there is the possibility of large or oversized dirt.

  In addition, when it is detected only in the boundary region (interference region) 27 and not detected in the bright region 28 and the dark region 29, it can be determined that it is a small and deep sharp line flaw or a medium-sized stain.

  Further, when it is detected in the dark region 28, it is often determined that the dent is a moderately large dent, and when it is detected only in the dark region 29, it can be determined that it is a very shallow dent. . If the boundary region (edge region) 27 is detected in addition to the dark region 29, it can be determined that the dent is shallow. Further, when any of the bright region 28, the boundary region (boundary region) 27, and the dark region 29 is detected, it has a deep or extremely deep (ultra deep) dent, or an extra large size and an extremely deep (ultra deep) convex. It can be judged that it is a sharp point scratch.

  In this way, by determining based on the combination pattern of the inspection results under different optical conditions for the same part, it can be detected only under specific optical conditions among the bright area 28, the dark area 29, the boundary area (edge area) 27, and the like. Not only can surface defects be detected, but the type of surface defects can be determined.

  Further, even if an abnormality suspected to be a surface defect is detected under certain optical conditions by determining the type of surface defect, the type of surface defect whose abnormality cannot be tolerated by the discriminating means of the management computer 80 Whether or not it is to be evaluated. As a result, it is possible to prevent a situation in which the type of the surface defect is not acceptable in spite of an acceptable surface defect, and the product is handled as a defective product, thereby improving the yield.

[Second Embodiment]
Next, a second embodiment of the present invention will be described with reference to the drawings.

  This 2nd Embodiment is a manufacturing system of the cylindrical body 90 provided with the surface inspection apparatus 1 concerning 1st Embodiment mentioned above.

  FIG. 17 is a functional block diagram showing a configuration of a cylindrical body manufacturing system 700 according to the second embodiment.

  The manufacturing system 700 includes a pipe manufacturing apparatus 710 for manufacturing the cylindrical body 90, the above-described cylindrical surface inspection apparatus 1, and a feedback unit 720 that feeds back the inspection result of the surface inspection apparatus 1 to the pipe manufacturing apparatus 710. I have.

  For example, if the photosensitive drum base is to be piped by drawing an aluminum alloy, the pipe making apparatus 710 is a process for dissolving the raw material to produce an extruded material, an extrusion process, a drawing process, a bending correction process, a predetermined correction process, etc. It is configured as a set of mechanical devices that perform a cutting process to length, a rough cleaning process, a finishing cleaning process, and the like. In addition, the pipe making apparatus 710 may not perform all these processes. This pipe making apparatus 710 functions as a forming means for forming a cylindrical body that is an article for which surface accuracy is required.

  The extrusion process is a process of obtaining an aluminum extruded element tube by extruding, for example, an aluminum billet.

  FIG. 18 is a schematic plan view of an extruder that performs this extrusion process. The aluminum extruding element tubes 740 extruded from the extruder main body 730 are conveyed forward in the extrusion direction by a plurality of pairs of support rollers 750, and are cut into a predetermined length R by a cutting machine 760.

  FIG. 19 is a cross-sectional view of an example of an extrusion die provided in the extruder body. This extrusion die 770 is a port hole die, 771 is a female die, and 772 is a male die. The die female die 771 is formed with a through-hole through-hole 773 formed in the center, and the peripheral surface on the inlet side of the extrusion hole 773 is a circular bearing portion 774. Reference numeral 775 denotes a relief portion. On the other hand, the die male die 772 has a molding convex portion 776 having a circular cross section at the center thereof, and a circular bearing portion 777 is formed on the tip peripheral surface of the molding convex portion 776. Reference numeral 778 denotes a passage hole through which the aluminum billet passes. Then, the die female die 771 and the die male die 772 are combined, and the tip of the molding convex portion 776 of the male die 772 is desired in the extrusion hole 773 of the female die 771, and both male and female bearing portions 774, 777 are annular. They are arranged opposite to each other with a molding gap 779 therebetween.

  The extrusion method is not particularly limited, and may be one using a porthole die or mandrel extrusion.

  The drawing process is a process of drawing an aluminum extruded tube having a predetermined length obtained by extrusion to obtain an aluminum drawn tube.

  FIG. 20 is a cross-sectional view showing an example of a drawing machine that performs this drawing step. For example, the drawing machine 780 includes an aluminum extrusion tube 781 passed between a drawing die 782 and a drawing plug 783, and a mouth portion 784 formed at the tip of the extrusion tube 781 is gripped by a chuck 785 of the carriage portion. By moving the carriage portion forward, an aluminum drawing tube 786 is obtained. The extraction plug 783 is supported by a rod 787. One or a plurality of cores 788 are attached to the rod 787 over substantially the entire length thereof, and the core 788 abuts against the inner peripheral surface of the extrusion element pipe 781 and pushes the extrusion element pipe 781 by its own weight. Therefore, the axis of the extruded element pipe 781 can be held in a state where it coincides with the axis of the die 782 from the beginning to the end of drawing. Further, during the drawing process, lubricating oil is supplied between the drawing die 782 and the extrusion element pipe 781.

  In this drawing step, the drawing may be performed by a floating plug drawing method in which the plug is not fixed. The drawing may be performed only once to obtain an aluminum drawn tube. However, it is preferable to repeat the drawing a plurality of times to reduce the diameter in order to obtain the aluminum drawn tube. In particular, it is preferable to obtain an aluminum drawn tube by performing drawing twice.

  The bending correction process is a process of correcting the bending of the aluminum drawn tube obtained by the drawing process. Specifically, the aluminum drawn tube obtained by the drawing process is first removed at its mouth by a press cutting method, then put into a roll straightening machine, and straightened by the action of an internal straightening roll. .

  FIG. 21 is a cross-sectional view illustrating an example of a cutting machine that performs the mouthpiece part cutting step. This cutting machine 790 inserts the end portion of the aluminum drawing tube 791 on the side of the mouthpiece 792 into the inside of the molds 793 and 793, and lowers the cutting blade 794 to cut and remove the mouthpiece portion 792. Since this cutting is performed by a parting blade, no chips are generated, and chips and the like are brought into the roll straightening machine so that the aluminum drawing tube 791 is not scratched.

  FIG. 22 is a conceptual diagram illustrating an example of a roll straightening machine that performs a bending straightening process. The roll straightening machine 810 straightly straightens the aluminum drawing tube 811 whose mouth is cut off by the action of the straightening roller 812 inside.

  The rough cleaning step is a step of removing lubricating oil or the like adhering to the aluminum drawing pipe in the drawing step or the like. This rough cleaning process is performed using, for example, a solvent having a degreasing power. Although it does not specifically limit as a specific method, For example, the immersion method, the shower method, etc. are mentioned.

  The finish cleaning step is preferably performed by ultrasonic cleaning, for example.

  FIG. 23 is a conceptual diagram illustrating an example of an ultrasonic cleaning machine. This ultrasonic cleaning machine 830 immerses a plurality of aluminum drawing tubes 833 that are objects to be cleaned in the cleaning liquid 832 stored in the cleaning increment 831, and sends ultrasonic waves into the cleaning liquid 832 by the vibrator 834. The aluminum drawing tube 833, which is an object to be cleaned, is cleaned.

  The ultrasonic irradiation method is not particularly limited, and an adhesive type, a vibration transmitter type, and other various washing machines can be used in addition to the above-described throwing type. The cleaning liquid is generally white kerosene, light oil, alkali, surfactant, trichloroethylene, or the like, but is not limited thereto, and water-based, hydrocarbon-based, chlorinated organic solvents, etc. may be used as appropriate. Good.

  The cylindrical body (aluminum drawing tube) 90 obtained through the extrusion process, the cutting process, the drawing process, the bending correction process, the cleaning process, and the finishing cleaning process as described above has excellent surface quality accuracy, and is a copier, printer, facsimile machine. It is suitable as a photosensitive drum substrate of an electrophotographic apparatus such as the above.

  The cylindrical body (aluminum drawn pipe) 90 manufactured in this way is inspected by the surface inspection apparatus 1 as to whether or not the surface state is within a predetermined allowable range, and the inspection result is within the predetermined allowable range. If there is, the cylindrical body 90 is determined as a finished product.

  Further, in the surface inspection apparatus 1, when the type or characteristic of the defect occurring in the cylindrical body 90 is determined, the feedback unit 720 feeds back the inspection result to the pipe making apparatus 710, thereby the defective pipe It is designed to prevent the occurrence of this.

  In the pipe manufacturing apparatus 710 to which the inspection result is fed back in this manner, the pipe manufacturing conditions are set according to the contents of the inspection result. Specifically, setting of extrusion conditions such as extrusion die attachment state and extrusion speed, selection of raw pipe, confirmation of attachment state of drawing die and setting of drawing conditions such as drawing speed, adjustment of roll height in roll straightener The roll straightening machine conditions such as the transport speed and the like are controlled. As a result, it is possible to obtain a cylindrical body having a necessary and sufficient surface accuracy more reliably, and even when a defective pipe is generated, it is possible to quickly cope with this and suppress the number of generated defective pipes.

  According to such a manufacturing system 700, a cylindrical body having a predetermined shape accuracy and a set of cylindrical bodies can be reliably obtained.

[Other Embodiments]
(1) In the above embodiment, when setting a combination pattern for the presence or absence of defect detection, the optical conditions are classified into three areas: a bright area, a dark area, and a boundary area. The bright area and the dark area may be further classified into a plurality.

  (2) In the above embodiment, the bright area and the dark area are simultaneously formed in the inspection target area. However, the bright area and the dark area may be sequentially formed.

  (3) In the above embodiment, the camera is configured from a line sensor camera. However, an area sensor having an imaging region having a two-dimensional extent, a camera configured from an optical sensor that detects a specific one-point light amount, and the like. It may be adopted.

  (4) In the above embodiment, the dark region and the boundary region are formed by using the light shielding body. However, a dark region in which reflected light is not directly detected by the camera may be configured depending on the angular relationship between the illumination and the camera.

  (5) In the above embodiment, the bright and dark stripes are formed by the slit body in which the optical characteristics of the light transmitting part and the light shielding part do not change. However, the light quantity of the bright part and the dark part is obtained by the slit body using the neutral density filter (ND filter). May be adjusted. Moreover, the light quantity of a bright part and a dark part may be adjusted with the slit body using a liquid crystal panel, and you may enable it to change the light-shielding form continuously and freely.

  (6) In the above embodiment, one long light source is used, but a plurality of light sources may be used.

  (7) In the above embodiment, the surface inspection is performed while rotating the cylindrical body. However, the surface inspection may be performed while continuously moving a long flat plate material or the like.

  FIG. 24 shows an example in which surface inspection is performed while continuously moving a long flat plate material. In this example, a slit body 62 having light-transmitting portions 623... And light-shielding portions 624. The illumination from the light source 61 is irradiated on the flat plate material 93.

  Thereby, each part of the flat plate 93 passes through the bright region 625..., The dark region 626. Then, the plurality of cameras 63... Having line sensors are arranged so that different areas in the moving direction of the flat plate material become detection regions 631. In this way, detection is performed under various different optical conditions including a bright region 625..., A dark region 626.

  FIG. 25 is another example in which surface inspection is performed while continuously moving a long flat plate material. In this example, a plurality of sets of light sources 64 and slit bodies 65 are arranged so as to form light and dark stripes at different positions in the width direction orthogonal to the feeding direction of the flat plate material 93, and a plurality of cameras 66 are provided with each light and dark stripe. By being arranged so as to be in charge of each detection region 661, each part of the flat plate 93 can be detected under various different optical conditions including a bright region 655, a dark region 656, and a boundary region. .

It is a perspective view of the cylindrical body which is a test object of the surface inspection apparatus concerning 1st Embodiment. It is a front view of the surface inspection apparatus concerning a 1st embodiment of the present invention. It is a top view of the apparatus. It is a side view of the same apparatus. It is a front view of the chuck | zipper part in 1st Embodiment. It is a side view of the chuck part. It is a perspective view of the light-shielding body in 1st Embodiment. It is a side view showing the outline of the principal part of the cylindrical surface inspection apparatus concerning a 1st embodiment. It is the same perspective view. It is explanatory drawing of the optical conditions of each site | part of the test | inspection area | region seen from the camera. It is explanatory drawing of the various optical conditions in the image image | photographed with the camera. It is explanatory drawing when a surface defect does not exist in a dark area | region. It is explanatory drawing when a surface defect exists in a dark area. It is explanatory drawing of the image obtained by image | photographing continuously with a camera, rotating a cylindrical body. It is explanatory drawing which shows the example of the image processing process performed by an image processing apparatus. It is an example of the relationship between the combination pattern of the presence or absence of the defect detection in each optical condition, and the kind of surface defect. It is a functional block diagram which shows the structure of the manufacturing system of the cylindrical body concerning 2nd Embodiment. It is a schematic plan view of the extruder which performs an extrusion process. It is sectional drawing in an example of the extrusion die with which an extruder main body is provided. These are the cross sections which show an example of the drawing machine which performs this drawing process. It is sectional drawing which shows an example of the cutting machine which performs a lip attachment part cutting process. It is a conceptual diagram which shows an example of the roll straightening machine which performs a bending correction process. It is a conceptual diagram which shows an example of an ultrasonic cleaner. This is an example in which surface inspection is performed while continuously moving a long flat plate material. It is another example which performs a surface test | inspection, moving a long flat plate material continuously.

Explanation of symbols

10 Illumination 20 Shading body (slit body)
23 Light-transmitting part 24 Light-shielding part 27 Boundary area 28 Bright area 29 Dark area 30 Camera 31 Detection area 80 Management computer 90 Cylindrical body

Claims (16)

A surface inspection method for detecting surface defects by irradiating an inspection target region with illumination light and detecting the reflected light with a camera,
For each part of the inspection target area, if there is no surface defect, there are a plurality of types including an optical condition that becomes a bright area where reflected light of illumination light is detected by the camera, and an optical condition that becomes a dark area where no reflected light is detected Detect surface defects under optical conditions,
Based on the combination pattern of presence or absence of defect detection under each optical condition, the type of detected surface defects shall be determined ,
A surface inspection method , wherein the bright region and the dark region are simultaneously formed in the detection region of the camera, and defect detection in the bright region and defect detection in the dark region are performed simultaneously . The surface inspection method according to claim 1 , wherein formation positions of the bright region and the dark region are moved. The plurality of optical conditions, the surface inspection method according to claim 1 or 2 including the optical conditions to be the bright and dark regions of the boundary region. By blocking the light shield illumination light irradiated on the inspection area, the surface inspection method according to any one of claims 1 to 3 for forming the dark area. By intermittently blocking the illumination light irradiated to the inspection target area by the slit body formed so that the plurality of light transmitting parts and the light shielding part are alternately repeated, the plurality of bright areas and surface inspection method according to any one of claims 1 to 3 for repeatedly forming a dark region alternately. Surface inspection method according to any one of claims 1 to 5, the detection of multiple surface defects is performed for at least 1 condition of the plurality of optical conditions. A surface inspection method for detecting surface defects by irradiating illumination light to the outer peripheral surface of a tubular body and detecting the reflected light with a camera,
In the detection area of the camera along the axial direction of the tubular body, if there is no surface defect, a bright area where the reflected light of the illumination light is detected by the camera and a dark area where the reflected light is not detected are alternately repeated,
While the tube body is rotated around the axis, the formation position of the bright region and the dark region is moved in the axial direction of the tube body, and the outer peripheral surface of the tube body is continuously photographed by the camera while the tube body is rotated a plurality of times. Thereby, for each part of the outer peripheral surface of the tubular body, the defect detection under a plurality of optical conditions including the optical region that is the bright region, the dark region, and the boundary region between the bright region and the dark region is performed,
Based on the combination pattern of presence or absence of defect detection under each optical condition, the type of detected surface defects shall be determined ,
In the detection region of the camera, the bright region, the dark region, and the boundary region between the dark region and the dark region are simultaneously formed, and defect detection in the bright region, defect detection in the dark region, and defect detection in the boundary region are performed. A method for inspecting a surface of a tubular body, characterized by being performed simultaneously . The light region and the dark region are alternately and repeatedly formed by intermittently blocking the illumination light applied to the tube body by a slit body formed so that a plurality of light transmitting portions and light shielding portions are alternately repeated. The surface inspection method according to claim 7 . The surface inspection method according to claim 7 or 8 , wherein a detection area by the camera is moved in an axial direction of the tubular body together with the bright area and the dark area. The surface inspection method according to claim 7 , wherein the tubular body is a photosensitive drum substrate. Forming an article requiring surface accuracy;
A surface inspection process for performing the surface inspection method according to any one of claims 1 to 10 as the inspection object,
Determining the article according to whether or not the type of defect determined by the surface inspection process satisfies a predetermined criterion, and determining the article as a finished product when the predetermined criterion is satisfied;
A method for producing an article, comprising: A photosensitive drum substrate manufactured by the method for manufacturing an article according to claim 11 . A surface inspection device that detects surface defects by irradiating an inspection target region with illumination light and detecting the reflected light with a camera,
An illumination system capable of forming a bright area in which reflected light of illumination light is detected by the camera and a dark area in which reflected light is not detected if there is no surface defect for each part of the inspection target area,
Under a plurality of optical conditions, including an optical condition that becomes a bright area and an optical condition that becomes a dark area with respect to each part of the inspection target area by the camera while changing the formation position of the bright area and the dark area by the illumination system Control means for performing defect detection;
Based on the combination pattern of the presence or absence of defect detection under each optical condition, determination means for determining the type of detected surface defects,
Equipped with a,
The surface inspection apparatus characterized in that the bright region and the dark region are simultaneously formed in the detection region of the camera, and defect detection in the bright region and defect detection in the dark region are performed simultaneously . Molding means for molding an article that requires surface accuracy;
The surface inspection apparatus according to claim 13 , wherein the article is an inspection target.
Discriminating the article according to whether or not the type of surface defect determined by the surface inspection apparatus satisfies a predetermined standard, and when the predetermined standard is satisfied, a determination unit that makes the article a finished product,
A manufacturing system characterized by comprising: A surface inspection device for detecting a surface defect of a tubular body,
Illumination for illuminating the outer peripheral surface of the tube with illumination light;
A camera that detects the reflected light of the illumination light in the detection region along the axial direction of the tubular body;
A plurality of light-transmitting portions and light-shielding portions are alternately formed, and the illumination light is intermittently blocked in the axial direction of the tube, so that the reflected light of the illumination light is detected by the camera if there is no surface defect. A slit body that alternately and repeatedly forms a bright area and a dark area in which reflected light is not detected;
While rotating the tube body around the axis, the slit body is moved in the axial direction of the tube body, and while the tube body is rotated a plurality of times, the outer peripheral surface of the tube body is continuously photographed by the camera. Control means for performing defect detection under a plurality of optical conditions, including optical conditions that are the bright region, the dark region, and a boundary region between the bright region and the dark region, for each part of the outer peripheral surface;
Based on a combination pattern of the presence or absence of defect detection under each optical condition, comprises a determination means for determining the type of surface defect detected ,
In the detection region of the camera, the bright region, the dark region, and the boundary region between the dark region and the dark region are simultaneously formed, and defect detection in the bright region, defect detection in the dark region, and defect detection in the boundary region are performed. A tubular surface inspection apparatus characterized by being performed simultaneously . Molding means for molding a tubular body that requires surface accuracy;
The surface inspection apparatus according to claim 15 , wherein the tubular body is an inspection object;
Classifying the tube according to whether or not the type of surface defect determined by the surface inspection apparatus satisfies a predetermined criterion, and a discriminating means that makes the tube a finished product when the predetermined criterion is satisfied;
A tubular body manufacturing system comprising: