JP2010078496A - Surface inspecting device and method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To rapidly perform the inspection of the surface by a simple and inexpensive constitution. <P>SOLUTION: The surface of a photosensitive drum 1 is irradiated with a laser beam Lb at a minute glazing angle θ and the scattered beam component Lb2 thereof is detected by the light detecting members SA, SB and SC arranged on a scattered beam region S3 due to a flaw and the light detecting member SAU arranged on a scattered beam region S2 due to a stain (surface roughness). No light detecting member is arranged on a regular reflected beam region S1. Then, the degree of the flaw and stain of the photosensitive drum 1 is judged on the basis of the intensity of light of the scattered beam component detected by the light detecting members and, on the basis of the judge result, it is judged whether the photosensitive drum 1 must be replaced to display the judge result. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a technique for inspecting the surface of an inspection object such as scratches and dirt, and in particular, the surface of the inspection object based on the light intensity of scattered light when irradiated with a non-dispersed light beam such as a laser light beam. It is related with the technique which inspects the state of.

  In image forming apparatuses such as electrophotographic copying machines, printers, and multifunction machines, photosensitive drums, intermediate transfer drums or belts, toner fixing rollers or belts, and the like are scratched by various frictions during their rotation. It is inevitable that this will occur.

  The scratches appear as streaks in the formed image, leading to a reduction in image quality. Therefore, when the scratches become large and the image quality is greatly reduced, the photosensitive drum, intermediate transfer drum or It is necessary to replace the belt, the toner fixing roller or the belt.

  In general, toner remains on the photosensitive drum, the intermediate transfer drum or belt, the toner fixing roller or belt, and the like after the image forming process is completed. The residual toner is removed by a cleaning blade or the like, and the above-described scratch may occur during the removal process.

  Further, it is difficult to completely remove the residual toner by the above-described removal process. Due to the residual toner that cannot be completely removed, a photosensitive drum, an intermediate transfer drum or belt, a toner fixing roller or belt, etc. The surface becomes dirty. When the degree of this stain becomes large, it becomes a main cause of scratches and image quality degradation.

  Therefore, it is necessary to replace the photosensitive drum, the intermediate transfer drum or belt, or the toner fixing roller or belt with a new one or the like at an appropriate time in relation to a decrease in image quality. is there.

  However, it is difficult to predict the time when the current scratches and stains become large and cause a reduction in image quality simply by looking at the scratches and stains. Therefore, if you try to replace the product when the image quality has actually deteriorated, the new product is out of stock, and the image formation process must be continued with the image quality deteriorated. There is also.

  For this reason, a technique for inspecting the surface of the photosensitive drum, intermediate transfer drum or belt, toner fixing roller or belt, etc., for scratches and dirt is required. Also, in various types of rollers for transporting recording paper, scratches and dirt on the roller surface cause jamming of the recording paper, so it is necessary to detect scratches and dirt on the roller surface.

  Conventionally, as a technique for inspecting the surface of an inspection object, the surface of the inspection object is imaged for each of a plurality of areas, and the captured images are compared as a set of two areas, so that any area has a defect. A technology for determining whether or not there is realized (see Patent Document 1).

  In addition, a measurement technique for measuring the surface roughness by irradiating laser light while changing the irradiation angle to the object to be measured and imaging a granular spot pattern that is reflected light of the laser light has been realized. (See Patent Document 2).

  Furthermore, a technology has been realized that irradiates a group of particles with laser light, images the diffracted light with a solid-state imaging device, and obtains the particle size distribution from the light intensity distribution of the annular region of the diffracted light or a partial region of the circular ring (See Patent Document 3).

Further, as a technique related to the image forming apparatus, a technique for detecting the toner adhesion amount by irradiating a reference image formed on the image carrier with light and receiving reflected light from the reference image is realized. (See Patent Document 4).
Japanese Patent Registration No. 28882409 JP 2004-125632 A Japanese Patent Registration No. 2805664 Japanese Patent Registration No. 3357470

  However, the appearance inspection apparatus of Patent Document 1 is an expensive and large-sized apparatus that includes an advanced image processing unit for accurately performing an appearance inspection, and inspects the surface of a component such as a photosensitive drum of the image forming apparatus. Not suitable for.

  Further, in the technique of Patent Document 2, in order to measure the surface roughness in a wide area of the surface of the object to be measured, it is necessary to perform scanning that moves the irradiation point of the laser beam, and the measurement is performed quickly and easily. I can't.

  Moreover, the measuring method of Patent Document 3 is a method for obtaining a particle size distribution, and is not a method for inspecting a surface state such as a scratch or a stain on the surface. Further, since the technique of Patent Document 4 uses reflected light from a reference image formed on an image carrier such as a photosensitive drum, it is not suitable for inspecting the surface of a member on which the reference image is not formed. is there.

  Therefore, there is a demand for a technique for quickly inspecting the surfaces of various members of the image forming apparatus with a simple and inexpensive configuration. In particular, there is a demand for a technique for quickly inspecting the surface of a member with a simple and inexpensive configuration while the member is incorporated in an image forming apparatus. Further, there is a similar demand for apparatuses and articles other than image forming apparatuses.

  The present invention has been made under the background of such a prior art, and an object thereof is to enable quick surface inspection with a simple and inexpensive configuration.

  In order to achieve the above object, a surface inspection apparatus according to the present invention is configured to irradiate a non-dispersed light beam all at once on a straight line on the surface of an inspection object without scanning, and the irradiation unit A light receiving means for receiving the scattered light component of the reflected light of the non-dispersed light beam, and a determination means for determining the surface state of the inspection object based on the light intensity of the scattered light component received by the light receiving means; It is characterized by having.

  Further, the surface inspection method according to the present invention includes an irradiation step of collectively irradiating a non-dispersed light beam to a straight line on the surface of an inspection object without scanning, and the non-dispersed light beam irradiated by the irradiation step. A light receiving step for receiving the scattered light component of the reflected light, and a determination step for determining the state of the surface of the inspection object based on the light intensity of the scattered light component received by the light receiving step. Features.

  According to the present invention, it is necessary to reduce the diameter of the non-dispersed light beam and to perform scanning by a configuration such as irradiating the non-dispersed light beam to the straight line on the surface of the inspection object all at once without scanning. Therefore, it is possible to perform surface inspection quickly with a simple and inexpensive configuration.

  The best mode for carrying out the present invention will be described below with reference to the drawings.

[First Embodiment]
FIG. 1 is a cross-sectional view showing a schematic configuration of an image forming apparatus to which a surface inspection apparatus according to an embodiment of the present invention is applied. The image forming apparatus illustrated in FIG. 1 is an electrophotographic image forming apparatus, and includes a photosensitive drum 1, an exposure scanning unit 2, a developing rotary 3, an intermediate transfer belt 4, and a fixing device 5.

  The photosensitive drum 1 has a cylindrical shape, and a photosensitive layer is formed on the surface thereof. The scratches and dirt on the photosensitive layer on the surface lead to a decrease in image quality. Therefore, in this embodiment, scratches and dirt on the surface of the photosensitive drum 1 are detected by a method described later, and a detection result, a message for prompting the replacement of the photosensitive drum 1, and the like are displayed.

  The photosensitive drum 1 is rotationally driven by a drum motor 24 (see FIG. 2). The exposure scanning unit 2 exposes and scans the photosensitive drum 1 with a laser beam modulated based on the image data. By this exposure scanning, an electrostatic latent image is formed on the photosensitive layer on the surface portion of the photosensitive drum 1.

  The exposure scanning unit 2 includes a laser unit 2a, a polygon mirror 2b, a BD sensor 2c, and a reflection mirror 2d. The polygon mirror 2b is rotationally driven by a polygon motor 2e. In FIG. 1, the laser unit 2 a is arranged on the back side or the near side of the page with respect to the polygon mirror 2 b.

  The laser unit 2a irradiates each mirror surface of the polygon mirror 2b being rotationally driven with laser light modulated based on the image data. The rotation of the polygon mirror 2b continuously changes the incident angle of the laser beam on each mirror surface of the polygon mirror 1b, and the reflected light is relative to the direction of the rotation axis of the photosensitive drum 1 (Z direction in FIG. 3). Proceed to Thereby, exposure scanning (main scanning) for one line by image light (laser light) is performed on each mirror surface.

  The BD sensor 2c is provided for the purpose of synchronizing the image writing position between the main scanning lines, and the output signal (BD signal) of the BD sensor 2c is used as a main scanning synchronization signal. The reflecting mirror 2d is provided to change the traveling direction of the reflected light from the polygon mirror 2b to the direction of the photosensitive drum 1.

  The developing rotary 3 stores toners of Y (yellow), M (magenta), C (cyan), and BK (black), respectively, and causes these toners to fly toward the photosensitive drum 1. 3C, 3BK. The developing unit 3 is rotationally driven by a developing rotary motor 25 (see FIG. 3). By this rotational drive, the toner units 3Y, 3M, 3C, and 3BK of the respective colors sequentially pass through the positions facing the photosensitive drum 1. During this passage, the toner of the color flies to the photosensitive drum 1, and the electrostatic latent image on the photosensitive drum 1 is developed as a visible toner image of the color.

  The intermediate transfer belt 4 is stretched by a large-diameter driving roller and a plurality of stretching rollers 17 and the like, and is rotationally driven by using a main motor 23 (see FIG. 3) connected to the driving roller as a driving source. As the intermediate transfer belt 4 rotates, the toner image on the photosensitive drum 1 is primarily transferred onto the intermediate transfer belt 4 in a laminated state.

  A reference mark 4b is formed on the intermediate transfer belt 4, and the reference mark 4b is detected by a light reflection type peripheral sensor 4a. The detection signal (peripheral length signal) from the peripheral length sensor 4a is used for laminating the toner images of the respective colors on the intermediate transfer belt 4 without any color misregistration.

  The toner images of the respective colors in the stacked state that are primarily transferred onto the intermediate transfer belt 4, that is, full-color toner images are secondarily transferred onto the recording paper P by the secondary transfer roller 6. The recording paper P is fed from the paper feed cassette 7 or the manual feed tray 8 to a secondary transfer position facing the secondary transfer roller 6 by a transport roller group or the like.

  The toner image secondarily transferred onto the recording paper P is fixed onto the recording paper P by a heating / pressurizing process using the heating roller 5a and the pressure belt 5b of the fixing device 5. Thereafter, the recording paper P is discharged to the paper discharge unit 9. The pressure belt 5b is stretched by a large-diameter drive roller, a tension roller 18 and the like.

  The toner remaining on the surface of the photosensitive drum 1 after the primary transfer is scraped off from the photosensitive drum 1 by the cleaning blade 10. Further, the toner remaining on the surface of the intermediate transfer belt 4 after the secondary transfer is scraped off from the intermediate transfer belt 4 by the cleaning blade 11.

  In this image forming apparatus, in order to optically detect scratches, dirt, etc. (mainly toner dirt) on the surface of the photosensitive drum 1, the intermediate transfer belt 4, the heating roller 5a of the fixing device 5, and the pressure belt 5b, Laser light emitting members 12, 13, 14, and 15 are provided, respectively. The environment sensor 16 is also used when this scratch and dirt detection processing is performed. This detection process will be described later in detail.

  Next, the configuration of the control system of the image forming apparatus in FIG. 1 will be described with reference to FIG. The electrophotographic image forming process by the image forming apparatus is executed under the control of the CPU 21. The CPU 21 is connected to a memory 22, a main motor 23, a drum motor 24, a developing rotary motor 25, a laser unit 2a of the exposure scanning unit 2, a BD sensor 2c, and a polygon motor 2e. Also connected to the CPU 21 are a circumference sensor 4a, an environmental sensor 16, laser light emitting members 12 to 15, light receiving members SA, SAU, SB, SC, SD, SE, SF, and a liquid crystal display unit 26.

  The CPU 21 executes the above-described electrophotographic series of image forming processes using each of the above devices. The memory 22 includes a ROM (not shown), an EEPROM 22a, and a RAM 22b. The ROM stores application programs related to the series of image forming processes described above.

  The EEPROM 22a stores application programs and the like related to inspection processing (including surface scratches and dirt detection processing) of the photosensitive drum 1, the intermediate transfer belt 4, the heating roller 5a of the fixing device 5, and the pressure belt 5b. ing. The CPU 21 uses the RAM 22b as a work area when executing these programs.

  The main motor 23 powers the sheet conveyance operation such as picking up, feeding, and discharging the recording sheet from the sheet feeding cassette 7, and the rotational operation of the intermediate transfer belt 4, the heating roller 5a of the fixing device 5, and the pressure belt 5b. Used as a source. The main motor 23 is also used as a power source for the rotation operation of the developing sleeve (not shown) of the toner units 3Y, 3M, 3C, 3BK.

  The drum motor 24 is used as a power source that rotationally drives the photosensitive drum 1. The development rotary motor 25 rotationally drives the development rotary 3 under the control of the CPU 21 to sequentially rotate the toner units 3Y, 3M, 3C, 3BK to the development position facing the photosensitive drum 1.

  The laser unit 2 emits image light (laser light) reflecting image data toward the polygon mirror 2b under the control of the CPU 21. The circumference sensor 4 a detects a reference mark 4 b marked on the intermediate transfer belt 4. The CPU 21 calculates the circumferential length of the intermediate transfer belt 4 based on the reference mark detection signal, and superimposes the Y, M, C, and BK toner images on the intermediate transfer belt 4 in a form that does not shift. To control.

  The environmental sensor 16 detects temperature and humidity. Based on the detected temperature and humidity, the CPU 21 performs control so as to perform an optimal image forming operation according to the current natural environment at the location where the image forming apparatus is disposed, for example, by changing the charging voltage of the photosensitive drum 1. To do. Further, the temperature and humidity detected by the environment sensor 16 are also used for automatic selection processing (to be described later) of the light receiving members SA to SF and SAU. In order to perform this automatic selection processing, the EEPROM 22a is pre-registered with identification information of a light receiving member to be selected at the temperature and humidity in association with the temperature and humidity information.

  The laser light emitting members 12 to 15 are constituted by inexpensive semiconductor lasers having a laser wavelength of 650 nm (red laser), an emission power of 1 mW, and a beam diameter of about 2 mm to 3 mm, and perform laser light emission operation under the control of the CPU 21. Laser light from the laser light emitting member 12 is applied to the surface of the photosensitive drum 1 with a minute glazing angle in order to detect scratches and dirt on the surface of the photosensitive drum 1. Laser light from the laser light emitting member 13 is applied to the surface of the intermediate transfer belt 4 with a minute glazing angle in order to detect scratches and dirt on the surface of the intermediate transfer belt 4.

  Laser light from the laser light emitting member 14 is applied to the surface of the heating roller 5a at a minute glazing angle in order to detect scratches and dirt on the surface of the heating roller 5a of the fixing device 5. Laser light from the laser light emitting member 15 is applied to the surface of the pressure belt 5b at a minute glazing angle in order to detect scratches and dirt on the surface of the pressure belt 5b of the fixing device 5. The “minute glazing angle” will be described in detail later.

  The light receiving members SA, SAU, SB, and SC are provided to receive the scattered light component of the reflected light of the laser light irradiated on the surface of the photosensitive drum 1 by the laser light emitting member 12. The light receiving member SD is provided to receive the scattered light component of the reflected light of the laser light irradiated on the surface of the intermediate transfer belt 4 by the laser light emitting member 13.

  The light receiving member SE is provided to receive the scattered light component of the reflected light of the laser light irradiated on the surface of the heating roller 5a by the laser light emitting member 14. The light receiving member SF is provided to receive the scattered light component of the reflected light of the laser light irradiated on the surface of the pressure belt 5b by the laser light emitting member 15.

  In the present embodiment, as the light receiving members SA to SF, SAU, a single photodiode, a phototransistor or the like (light receiving element for one pixel), an inexpensive optical sensor that detects light at a pinpoint is used. Assumed.

  An inspection principle for inspecting scratches and dirt on the surface of the photosensitive drum 1 and the like by irradiation with a laser beam (non-dispersed light beam) will be described with reference to FIGS.

  As shown in FIG. 3, the laser light emitting member 12 irradiates the surface (tangent plane) of the photosensitive drum 1 with the laser light Lb at a minute glazing angle θ (θ = π / 2−incident angle). The minute glazing angle θ is a minute angle such that a straight line related to at least the photosensitive layer region of the photosensitive drum 1 is collectively irradiated (see the irradiation region Sd in FIGS. 4 to 7).

  In other words, the minute glazing angle θ is the cutting length of the laser beam Lb by the photosensitive drum 1 when the surface of the photosensitive drum 1 is irradiated with the laser beam Lb (the cutting length in the Z-axis direction in FIG. 4 and the like). Is an angle that is at least the length of the photosensitive layer of the photosensitive drum 1 in the Z-axis direction.

  By irradiating the laser beam Lb with such a small glazing angle θ, one straight line of the photosensitive layer of the photosensitive drum 1 can be easily obtained without scanning the laser beam Lb, that is, without controlling the movement of the aiming point. It is possible to irradiate the laser beam Lb at once. Furthermore, it is possible to speed up the surface inspection.

  As shown in FIG. 3, the regular reflected light component Lb1 of the reflected light of the laser beam Lb irradiated to the photosensitive drum 1 with a minute glazing angle θ is received by any of the light receiving members SA, SAU, SB, and SC. Never happen. On the other hand, the scattered light component Lb2 is received by the light receiving members SA, SAU, SB, and SC.

  When there is no scratch or dirt on the surface of the photosensitive drum 1, almost all of the reflected light of the laser beam Lb irradiated on the photosensitive drum 1 becomes a regular reflection light component Lb1, and the regular reflection shown in FIGS. It passes through the light region S1. However, the light receiving members SA, SAU, SB, and SC are not provided in the regular reflection light region S1, and are hardly received by these light receiving members.

  On the other hand, when the surface of the photosensitive drum 1 is scratched, a part of the reflected light of the laser beam Lb irradiated to the photosensitive drum 1 becomes a scattered light component Lb2 and is received by the light receiving members SA, SAU, SB, and SC. Is done. When the surface of the photosensitive drum 1 is dirty, part of the reflected light of the laser light Lb irradiated to the photosensitive drum 1 becomes a scattered light component Lb2 and is received by the light receiving member SAU.

  As described above, the scattered light component Lb2 is received by the light receiving members SA, SAU, SB, and SC because these light receiving members are arranged in the scattered light region shown in FIGS. 3 to 7 based on the experimental results. It is.

  Here, the above experiment will be described. In this experiment, as shown in FIGS. 4 to 6, a commercially available inexpensive laser irradiator comprising a semiconductor laser and an optical lens having a laser wavelength of 650 nm (red laser), an emission power of 1 mW, and a beam diameter of about 2 mm to 3 mm. L was used. With this laser irradiator L, the surface of the photosensitive drum 1 was irradiated with laser light with a minute glazing angle.

  The photosensitive drum 1 has a diameter of 62 mm and a length in the longitudinal direction (Z-axis direction) of 460 mm. Laser light was irradiated with a minute glazing angle to a region from a position (longitudinal center Zd2) of about 230 mm corresponding to half the length of the photosensitive drum 1 to the end Zd3 on the back side. As the photosensitive drum 1, a used product in which a large number of scratches K (scratches on the circumferential stripe) occurred in the circumferential direction (rotation method) was used at first (see FIG. 4).

  In this experiment, the scattered light component considered to be caused by the scratch K in the region from the longitudinal center Zd2 to the end Zd3 on the back side is in the normal direction to the laser light irradiation surface of the photosensitive drum 1 (shown in FIG. 4). It was found that it was distributed in the (X-axis direction). Therefore, when the scattered light component is measured with a measure while holding the paper over the XY plane at the Z position of the end Zd3 on the back side of the photosensitive drum 1, the scattered light component exceeds 200 mm from the end Zd3. It reached the position in the X-axis direction. In addition, the scattered light component tended to decrease its light intensity as it moved away from the photosensitive drum 1.

  From this experimental result, when the laser light is irradiated to the region from the front end Zd1 to the back end Zd3 of the photosensitive drum 1 with a finer glazing angle, the scattered light component further increases in the X-axis direction. Expected to extend. Therefore, when such laser light irradiation was actually performed, as expected, the scattered light component further extended in the X-axis direction (see S3 in FIGS. 4 and 7).

  In the experiment based on this prediction, the laser beam was not directly irradiated onto the photosensitive drum 1 from the laser irradiator L, but was irradiated through the light pipe LP as shown in FIGS. This is because the experiment was performed in a state where the photosensitive drum 1 was actually incorporated in the image forming apparatus, so that there was not enough space for arranging the laser irradiator L in the apparatus. Therefore, even when the surface inspection apparatus according to the present embodiment is mounted on an apparatus such as an image forming apparatus, it is desirable to irradiate laser light through a light guide member such as a light pipe LP as necessary.

  On the other hand, in the first experiment, the specularly reflected light component was distributed in the specularly reflected light region (see S1 in FIGS. 4 to 7) as spot light having a high light intensity. The shape of the regular reflection light region S1 was not a circle but an ellipse having the major axis in the X-axis direction. As described above, the specularly reflected light region S1 has an elliptical shape whose major axis is the X-axis direction. The specularly reflected light component or the scattered light component is also close to the specularly reflected light component even in the portion of the scratch K. This is thought to be because the reflection part that generates sine remains.

  Next, as shown in FIG. 5, a laser beam was irradiated at a minute glazing angle on the photosensitive drum 1 having the toner stain TY in the circumferential direction. In this case, a new scattered light component is seen in a wide region (see STY in FIG. 5) surrounding the regular reflection light region S1, and almost no scattered light component is seen in the scattered light region S3 resulting from the scratch K. It was.

  That is, the scattered light region STY caused by the circumferential toner stain TY is a relatively wide region surrounding the specularly reflected light region S1 and a scattered light region S2 described later, and is similar to the scattered light region S3 caused by the scratch K. It did not extend long in the X-axis direction. Further, while the scattered light region S3 caused by the scratch K extends in the X-axis direction and elongated, the scattered light region STY caused by the circumferential toner contamination is radially wide with the specularly reflected light region S1 as the center. It spread at an angle.

  As described above, the phenomenon in which the scattered light region S3 caused by the scratch differs from the scattered light region STY caused by the toner stain is that the scattered light component and the toner stain caused by the scratch are obtained by devising the arrangement position of the light receiving member. This means that the resulting scattered light components can be detected in a distinguishable manner. Therefore, in the present embodiment, in addition to the light receiving members SA, SB, and SC that detect scattered light components caused by scratches, a light receiving member SAU that detects scattered light components caused by dirt is separately provided.

  In addition, as shown in FIG. 6, the laser beam was similarly irradiated to the area | region from the edge part of this near side to the edge part of the back side with respect to the new photosensitive drum 1 with a very small glazing angle. In this experiment, almost no scattered light component was observed in the region far from the photosensitive drum 1, but in the region close to the photosensitive drum 1 (see S2 in FIGS. 4 to 7), a scattered light component with low light intensity was observed. . Of course, in the regular reflection light region S1, a regular reflection light component having a high light intensity was observed. However, the shape of the oval shape (the X direction is the long axis) of the regular reflection light region S1 is closer to a circle than that of a used photosensitive drum.

  The scattered light component having a low light intensity in the scattered light region S2 has a slight unevenness, that is, a certain degree of surface roughness, even if it is a new photosensitive drum. It can be inferred that this is caused. Therefore, an experiment was actually performed with a member (mirror or the like) whose surface roughness was sufficiently smaller than the surface of the new photosensitive drum 1. As a result, although the specularly reflected light component having a very strong light intensity was observed in the specularly reflected light region S1, almost no scattered light component was observed in the surrounding scattered light region S2, and the correctness of the above estimation was confirmed. Proven.

  Similarly, when the photosensitive drum having scratches and dirt in the rotation axis direction (Z-axis direction), not in the circumferential direction, was irradiated with laser light at a minute glazing angle, the scattered light component was very high. There were few. This means that when the surface inspection technique according to the present embodiment is applied to the surface inspection of other articles, the irradiation direction of the laser beam and the direction of scratches or dirt on the detection target are set to 90 degrees as much as possible. This suggests that scratches and dirt can be detected efficiently by intersecting at an angle close to 90 degrees.

  Note that scratches and dirt in the rotational axis direction (Z-axis direction) hardly occur in the photosensitive drum 1, the intermediate transfer belt 4, the heating roller 5a, and the pressure belt 5b, so that it is necessary to determine the replacement timing of these devices. In addition, there is little need to detect scratches and dirt in the Z-axis direction.

  In view of the experimental results of each of the above experiments, in the present embodiment, as shown in FIGS. 3 to 7, the light receiving members SA and SB are used as the light receiving members that receive the scattered light component caused by the circumferential scratch K. , SC were arranged at both ends and the center of the scattered light region S3 caused by scratches.

  Further, the light receiving member SAU for receiving the scattered light component caused by the circumferential dirt is not a scattered light area STY caused by the circumferential toner dirt but a narrower one due to the space in the apparatus. It was arranged in the scattered light region S2 due to the surface roughness of the drum.

  In this case, there is a possibility that the detection accuracy of the scattered light component due to the toner stain TY in the circumferential direction is slightly lowered. However, the toner contamination TY can be eliminated by the cleaning process and is not an important determination material for determining the replacement timing of the photosensitive drum, so the detection accuracy of the scattered light component due to the circumferential toner contamination TY is slightly reduced. But that doesn't matter. Further, by appropriately setting reference information and limit information, which will be described later, it is possible to determine the degree of toner contamination TY in the circumferential direction with the same accuracy as that provided in the scattered light region STY. Therefore, there is no particular problem even if the light receiving member SAU for receiving the scattered light component due to the dirt in the circumferential direction is provided in the scattered light region S2 due to the surface roughness of the drum.

  Needless to say, the light receiving member SAU for receiving the scattered light component caused by the circumferential dirt may be disposed in the scattered light region STY caused by the circumferential toner dirt TY.

  Next, the location of the light receiving members SA, SAU, SB, and SC will be supplementarily described with reference to FIG.

  As a result of the above-described experiment, the scattered light region S3 caused by the scratch extends in the X-axis direction. The X-axis direction is a normal direction to a surface related to the laser light irradiation line (Z direction) of the photosensitive drum 1. That is, the scattered light region S3 is located on the Zθ0 plane shown in FIG.

  Therefore, the light receiving members SA, SB, and SC for detecting the scattered light component due to the scratch are in the X-axis direction (Zθ0 plane) at the Z coordinate position slightly behind the end Zd3 on the back side of the photosensitive drum 1. They are arranged in the upper scattered light region S3).

  In addition, the light receiving member SAU for detecting the scattered light component caused by dirt is the Zθa plane (scattered light region S2) that forms the predetermined angle θa with the Zθ0 plane at the same Z coordinate position as the light receiving members SA, SB, and SC. Has been deployed.

  The light receiving member SAU for detecting the scattered light component caused by the dirt is a Z-θa plane (scattered light) that forms a predetermined angle −θa with the Zθ0 plane at the same Z coordinate position as the light receiving members SA, SB, and SC. You may arrange | position to area | region S2) etc. Or you may arrange | position the light-receiving member for detecting the scattered light component resulting from dirt on both a Z (theta) a plane etc. and a Z- (theta) a plane. In short, a plurality of light receiving members for detecting the scattered light component caused by dirt may be provided as long as they are within the scattered light region S2 or the scattered light region STY.

  Further, the light receiving members can be arranged at different Z coordinate positions due to the space in the apparatus or the like without being arranged at the same Z coordinate position as described above.

  In the sub-scanning direction, it is not necessary to scan finely as in the case of image formation. For example, the laser beam is irradiated with a small glazing angle a plurality of times at a sub-scanning interval of about 90 ° rotation angle of the photosensitive drum 1. It is desirable to do. As a result, even if scratches and dirt are unevenly distributed in a partial region of the photosensitive drum 1 in the circumferential direction, it can be detected without missing it.

  Next, the scattered light component caused by scratches and dirt on the intermediate transfer belt 4 will be described with reference to FIG.

  As shown in FIG. 1, since the secondary transfer roller 6 exists at the right side position of the intermediate transfer belt 4, a laser beam irradiation experiment is performed as shown in FIG. The measurement was performed with a small glazing angle from the lower position of 17 to the intermediate transfer belt 4.

  In this case, since the laser beam was irradiated from the lower position as described above, the scattered light component spread in the −Y direction. Specifically, the regular reflection area ST1 is slightly larger than the regular reflection area S1 in the case of the photosensitive drum 1. Further, the scattered light region ST3 due to the scratch KT in the rotation direction of the intermediate transfer belt 4 is not elongated like the scattered light region S3 in the case of the photosensitive drum 1, but has a shape that is somewhat thick and short. In other words, the scattered light component caused by the scratch KT in the rotation direction of the intermediate transfer belt 4 has a larger spread angle and a shorter maximum separation distance from the laser light irradiation surface than in the case of the photosensitive drum 1. .

  Further, the scattered light region ST2 caused by the surface roughness (including the surface roughness due to dirt) of the intermediate transfer belt 4 is compared with the surface roughness (including the surface roughness due to dirt) in the case of the photosensitive drum 1. It was quite wide. Further, a considerably wide overlapping area exists between the scattered light region ST3 caused by the scratch KT in the rotation direction of the intermediate transfer belt 4 and the scattered light region ST2 caused by the surface roughness.

  These phenomena are considered to be because the diameter of the tension roller 17 is smaller than the diameter of the photosensitive drum 1 and the curvature of the portion irradiated with the laser light is larger than that of the photosensitive drum 1. Actually, in the case of the pressure belt 5b stretched by the tension roller 18 (see FIG. 1) having a diameter smaller than that of the tension roller 17 related to the intermediate transfer belt 4, the above-described scattering in the case of the intermediate transfer belt 4. The phenomenon of the light component appeared more markedly than in the case of the intermediate transfer belt 4.

  This means that the smaller the curvature, in other words, the closer to the flat state, the longer the scattering region of the scattered light component caused by the scratch extends in the normal direction to the laser light irradiation surface. Means. Therefore, the surface inspection technique according to the present embodiment can be applied not only to curved surfaces but also to flat surfaces.

  However, as is clear from the above description, the scattered light component extends longer in the normal direction to the laser light irradiation surface as the angle between the direction in which the scratch extends and the irradiation laser light approaches 90 °. Go. Therefore, in particular, when inspecting a planar surface with a small curvature, it is desirable to inspect a plurality of times by changing the direction of a straight line that collectively irradiates laser light with a minute glazing angle.

  In view of the phenomenon in which the scattered light regions ST2 and ST3 overlap, in the present embodiment, the light receiving member for detecting the scattered light component due to scratches and dirt on the intermediate transfer belt 4 is the above-described overlap. Only one light receiving member SD is provided in the region to reduce the number of parts.

  Although the detailed description is omitted, in the case of the fixing device 5 as well, the heating roller 5a and the pressure are applied to the overlapping region of the scattered light region caused by the scratch in the rotation direction and the scattered light region caused by the surface roughness. Light receiving members SE and SF that receive scattered light from the belt 5b are provided. However, as in the case of the photosensitive drum 1, the scattered light component due to the surface roughness (including the surface roughness due to dirt) and the scattered light component due to the scratch can be individually detected by different light receiving members. It is.

  In the present embodiment, the photosensitive drum 1, the intermediate transfer belt 4, and the fixing device 5 are performed by performing processing according to the flowcharts of FIGS. 9 and 10 using the laser light emitting members 12 to 15 and the light receiving members SA to SF and SAU. The surfaces of the heating roller 5a and the pressure belt 5b are inspected.

  The flowchart of FIG. 9 is a flowchart showing an outline of the surface inspection process of the photosensitive drum 1, the intermediate transfer belt 4, the heating roller 5a of the fixing device 5, and the pressure belt 5b. FIG. 10 is a flowchart showing details of the flaw / dirt determination processing in the processes P5, P9, and P13 of FIG.

  In the surface inspection process, the CPU 21 first acquires current temperature information and humidity information from the environmental sensor 16 (P1). Next, the CPU 21 determines whether or not the user has instructed execution of surface inspection of the photosensitive drum 1 (P2). If not, the process proceeds to a process P6 described later.

  The execution instruction for the surface inspection of the photosensitive drum 1 can be performed via a menu screen displayed on the liquid crystal display unit 26. On this menu screen, not only an instruction to perform surface inspection of the photosensitive drum 1, but also an instruction to inspect the surface of the intermediate transfer belt 4, the heating roller 5a of the fixing device 5, and the pressure belt 5b can be performed together.

  When an instruction to perform surface inspection of the photosensitive drum 1 is issued, the CPU 21 selects a light receiving member based on the acquired temperature information, humidity information, model (model) information of the image forming apparatus, and the like (P3). ). In this process P3, the CPU 21 selects one or a plurality of light receiving members from among the light receiving members SA, SAU, SB, and SC for performing the surface inspection of the photosensitive drum 1.

  Next, the CPU 21 irradiates the photosensitive drum 1 with laser light from the laser light emitting member 12 with a minute glazing angle, and measures the output signal of the selected light receiving member, that is, the light intensity of the scattered light component (P4). ).

  Next, the CPU 21 determines the degree of scratches and dirt on the photosensitive drum 1 based on the light intensity of the scattered light component obtained from the selected light receiving member (P5). Then, the CPU 21 further determines whether or not the photosensitive drum 1 is replaced based on the determination result (P5), and proceeds to the process P6.

  In process P6, the CPU 21 determines whether or not an instruction to perform surface inspection of the intermediate transfer belt 4 has been issued from the user. As a result, if the execution instruction for the surface inspection of the intermediate transfer belt 4 is not given, the CPU 21 proceeds to a process P10 described later.

  On the other hand, if the execution instruction for the surface inspection of the intermediate transfer belt 4 has been made, the CPU 21 selects the light receiving member based on the acquired temperature information, humidity information, model (model) information of the image forming apparatus, and the like ( P7). In this case, in this embodiment, since only the light receiving member SD is provided as the light receiving member for performing the surface inspection of the intermediate transfer belt 4, the CPU 21 inevitably selects the light receiving member SD. Become.

  Next, the CPU 21 irradiates the intermediate transfer belt 4 with laser light from the laser light emitting member 13 at a minute glazing angle, and measures the output signal of the selected light receiving member SD, that is, the light intensity of the scattered light component. (P8).

  Next, the CPU 21 determines the degree of scratches and dirt on the intermediate transfer belt 4 based on the light intensity of the scattered light obtained from the selected light receiving member SD (P9). The CPU 21 further determines whether or not the intermediate transfer belt 4 is exchanged based on the determination result (P9), and proceeds to the process P10.

  In process P10, the CPU 21 determines whether or not a user has instructed execution of surface inspection of the fixing device 5. As a result, if the execution instruction for the surface inspection of the fixing device 5 has not been issued, the CPU 21 ends the inspection process.

  On the other hand, if the execution instruction for the surface inspection of the fixing device 5 is given, the CPU 21 selects the light receiving member based on the acquired temperature information, humidity information, model (model) information of the image forming apparatus, etc. (P11). ).

  In the present embodiment, with respect to the fixing device 5, the heating roller 5a and the pressure belt 5b are individually inspected, and the light receiving members are used as light receiving members for performing surface inspection of the heating roller 5a and the pressure belt 5b, respectively. Members SE and SF are provided. Therefore, in the process P11, the CPU 21 inevitably selects the light receiving members SE and SF.

  Next, the CPU 21 irradiates the heating roller 5a and the pressure belt 5b with laser light from the laser light emitting members 14 and 15 with a minute glazing angle, respectively, and outputs signals from the light receiving members SE and SF according to selection, That is, the light intensity of the scattered light component is measured (P12).

  Next, the CPU 21 determines the degree of scratches and dirt on the heating roller 5a and the pressure belt 5b based on the light intensity of the scattered light components obtained from the selected light receiving members SE and SF (P13). Then, the CPU 21 further determines the necessity (necessity of replacement) of the fixing device 5 based on the determination result (P13), and ends this inspection process.

  If the structure of the fixing device 5 is such that the heating roller 5a and the pressure belt 5b can be individually replaced, in process P13, whether or not the heating roller 5a is replaced and whether or not the pressure belt 5b is replaced are individually determined. It is also possible to make a determination.

  Next, details of the scratch / dirt determination processing in processes P5, P9, and P13 of FIG. 9 will be described based on the flowchart of FIG.

  In the scratch / dirt determination process, the CPU 21 compares the measurement result (the light intensity of the scattered light component or the spread degree of the distribution) obtained from the selected light receiving member with the reference information corresponding to the light receiving member ( P21). Then, the CPU 21 determines whether or not the measurement result related to at least one selected light receiving member is equal to or more than the corresponding reference information (P22).

  The above-mentioned “spreading distribution” is intended for the fourth embodiment (area sensor) described later. This also applies to “etc.” in the description of “scattered light intensity etc.” in the processes P4, P8, P12 of FIG.

In addition, the “reference information” is used to determine in advance the intensity of the scattered light component and the like for a large number of objects to be inspected (photosensitive drums and the like) having different degrees of scratches and dirt by the same method as the processes P4, P8, and P12 in FIG. This is derived from the measured measurement results (the same applies to “limit information” described later). This “reference information” is information (information relating to light intensity) that is different for each light receiving member (each light receiving means), and is registered in advance in the EEPROM 22a in association with each light receiving member (the same applies to “limit information”). .
In addition, between the reference information and the limit information,
[Equation 1]
There is a relationship of reference information <limit information.

  When the measurement result related to at least one selected light receiving member is equal to or more than the corresponding reference information, the CPU 21 predicts that the main cause of the scattered light component is not the dirt but the scratch, and this is indicated in the liquid crystal display unit 26. (P23) and the process proceeds to process P25.

  On the other hand, if the measurement results for all the selected light receiving members are less than the corresponding reference information, the CPU 21 predicts that the main cause of the scattered light component is not the scratch but the dirt, and this is indicated in the liquid crystal display unit. 26 (P24), and the process proceeds to process P25.

  In the process P25, the CPU 21 calculates a difference between the measurement result of each selected light receiving member and the limit information corresponding to the selected light receiving member (the light intensity of the scattered light component or the limit information of the spread of the distribution). . This “limit information” is the light intensity of the scattered light component indicating the limit of scratches and dirt necessary to maintain a certain level of high image quality, or the degree of spread of the distribution.

  Further, the limit information is used as determination information when determining the surface state of the inspection object such as the photosensitive drum 1 based on the light intensity of the scattered light component, as will be apparent from the following description. Of course, the limit information (determination information) is obtained by measuring in advance the light intensity of the scattered light component related to the inspection target (same type: same model number) such as a photosensitive drum in various surface states, It is preset based on this. The limit information (determination information) is used when the surface inspection of the same type of inspection object is actually performed.

Next, the CPU 21 calculates the ratio (PC: percentage) of the measurement result (Re) to the limit information (Li) for each selected light receiving member (P25).
[Equation 2]
P. C. = Re / Li × 100
Next, with respect to the calculated ratio (PC: percentage), the CPU 21 determines large, medium, and small using the determination table (P26).

  In this determination table, large, medium, and small determination criteria (ranges) are determined for each light receiving member. In other words, even if the ratio is the same, for example, 80%, the determination result is not always the same for each light receiving member. For example, 80% in the light receiving member SA related to the scratch is determined to be “large”, but 80% in the light receiving member SAU related to the stain is determined to be “medium”.

  The reason why the large, medium, and small judgment criteria (ranges) are determined for each light receiving member is that the flaw has a high advancing speed and the dirt has a low advancing speed, and the light receiving members SA, SB, and SC related to the flaw are scattered This is because of considerations such as the speed at which the light intensity of the light component increases. The determination table is stored in advance in the EEPROM 22a.

  In this way, by deciding large, medium, and small judgment criteria (ranges) for each light receiving member, it is possible to extend the replacement time of the inspection object as much as possible within a range where deterioration in image quality is not noticeable, and to maintain maintenance costs. It becomes possible to reduce.

  Note that it is desirable to change the determination criteria of the determination table in the course of using the image forming apparatus (surface inspection apparatus). In this case, for example, each time surface inspection is performed, the measurement results are accumulated in a database, and the determination criteria are updated by more accurately grasping the progress of scratches and dirt from the accumulated measurement results. Can be considered.

  After making the determination in the determination table, the CPU 21 determines whether or not there is at least one selected light receiving member determined to be “large” (P27). As a result, if there is at least one selected light receiving member determined to be “large”, the CPU 21 needs to replace or clean the inspection target object (photosensitive drum or the like) corresponding to the selected light receiving member. A message to that effect is displayed on the liquid crystal display unit 26 (P28).

  Whether or not “replacement” is necessary is displayed for the selected light receiving member related to “scratches”, and whether or not “cleaning” is necessary is displayed for the selected light receiving member related to “dirt”. After performing this display process, the CPU 21 ends this determination process and returns to the flow of FIG.

  On the other hand, if there is no selected light receiving member determined to be “large”, the CPU 21 determines whether or not there is even one selected light receiving member determined to be “medium” ( P29). As a result, if there is at least one selected light receiving member determined to be “medium”, the CPU 21 does not need to replace or clean the object to be inspected corresponding to the selected light receiving member. Is displayed on the liquid crystal display unit 26 (P30).

  After performing this display process, the CPU 21 ends this determination process and returns to the flow of FIG.

  On the other hand, if there is no selected light receiving member determined to be “medium”, the CPU 21 displays on the liquid crystal display unit 26 that the object to be inspected corresponding to the selected light receiving member is good. (P31), this determination process is terminated, and the process returns to the flow of FIG.

  As described above, in the present embodiment, the CPU 21 irradiates the surface of the photosensitive drum 1 or the like with the laser light Lb with a minute glazing angle θ. The scattered light component Lb2 is received by the light receiving members SA, SB, SC disposed in the scattered light region S3 due to scratches and the light receiving member SAU disposed in the scattered light region S2 due to dirt (surface roughness).

  Then, the CPU 21 automatically selects the light receiving member based on the temperature, humidity, model, etc., and based on the light intensity of the scattered light component received by the selected light receiving member, scratches and dirt on the photosensitive drum 1 etc. Determine the degree (large, medium, small). Then, the CPU 21 determines whether or not the photosensitive drum 1 or the like should be replaced based on the determination result, and displays the determination result.

  In this surface inspection process, the beam diameter of the laser beam irradiated on the surface of the inspection object may be about 2 mm to 3 mm, the output power may be about 1 mW, the wavelength may be about 650 nm in red, and an inexpensive laser emitting member should be used. Can do.

  In addition, it is possible to perform surface inspection quickly by irradiating laser light to one line on the surface of the inspection object at once without scanning with laser light. Furthermore, the light receiving members SA to SF and SAU can also be constituted by inexpensive photodiodes, phototransistors, and the like. Therefore, it is possible to perform surface inspection quickly with a simple and inexpensive configuration.

  Note that the inspection method shown in FIG. 10 for inspecting the surface state of the inspection object based on the light intensity of the scattered light component is an example, and the inspection object is based on the light intensity of the scattered light component by other methods. It is also possible to inspect the surface condition.

[Second Embodiment]
As a light guide member for irradiating the surface of a device to be inspected with a minute glazing angle with laser light from a laser light emitting member, the light pipe LP shown in FIGS. 5 and 6 is used instead of the light pipe LP shown in FIG. Thus, it is also possible to use the mirror Mi. Further, although not shown, a lens, an optical fiber, a reflector, a transparent resin, or the like can be used as the light guide member. Note that only one of the various light guide members described above may be used, or two or more of them may be used in appropriate combination.

  By using such a light guide member such as the light pipe LP and the mirror Mi, when irradiating the inspection object with a minute glazing angle, the degree of freedom of the arrangement position of the laser light emitting member is increased. There is no need to increase the size of the forming apparatus.

  Further, the fixing device 5 that becomes high temperature, in particular, the laser light emitting member 14 for irradiating the heating roller 5a with laser light can be disposed at a position away from the heating roller 5a, and the laser light emitting member 14 having low heat resistance is thermally destroyed. It is possible to prevent fluctuations in the intensity of the laser light.

  Further, as shown in FIG. 11, the scattered light component is received by one light receiving member LGL via a wide-angle condensing member such as a light guide lens LGL without the light receiving member directly receiving light from the inspection object. It is also possible to configure.

  The light guide lens LGL has a lens function for collecting the scattered light component and a function for polarizing the traveling direction of the collected scattered light component by the reflecting portion. That is, even if the light guide lens LGL is shorter than the length of the scattered light region S3 due to scratches in the X-axis direction, the light guide lens LGL can sufficiently collect the scattered light component of the scattered light region S3.

  Therefore, when the wide-angle light condensing member is used, the space in the direction of the scattered light region S3 due to scratches cannot be taken sufficiently due to, for example, the location where the laser light emitting member is disposed and the light guiding member cannot be used. Even then, there is a high possibility that the scattered light component due to scratches can be received.

  Further, the use of the wide-angle light collecting member increases the degree of freedom of the arrangement position of the light receiving member. Accordingly, the light receiving members SE and SF for detecting the scattered light components from the heating roller 5a and the pressure belt 5b of the fixing device 5 that are at a high temperature are arranged at positions away from the heating roller 5a and the pressure belt 5b. Can do. Thereby, it is possible to prevent thermal destruction of the light receiving members SE and SF, level fluctuation of the detection signal, and the like.

[Third Embodiment]
In the configuration example of FIG. 12, the scattered light components from the photosensitive drum 1 are condensed using two elongated light collecting members F and G. This condensing member F is arranged in the Zθ0 plane substantially parallel to the Z axis in order to condense the scattered light component resulting from the scratch. Further, the condensing member G is disposed substantially parallel to the Z axis in the Zθa plane so as to collect the scattered light component caused by the dirt.

  The scattered light component collected by the light collecting member F is guided in the direction of the light receiving member SA and detected by the light receiving member SA.

  The scattered light component collected by the light collecting member G is guided in the direction of the light receiving member SAU and detected by the light receiving member SAU. By using such condensing members G and F, interference between the scattered light component and other components can be reduced, the degree of freedom of component arrangement in the device is increased, and the size of the device is avoided. be able to.

  In the configuration example of FIG. 12, the inspection target is irradiated with the laser light from the laser light emitting member L via the condenser lens Le. By using this condensing lens Le, the diameter of the laser light (beam light) emitted from the laser light emitting member L can be increased to some extent, and a cheaper laser light emitting member L can be used.

  In addition, the beam diameter and shape of the laser light can be optimized so that the light collection efficiency of the light collection members G and F is improved.

[Fourth Embodiment]
In the first to third embodiments described above, it is assumed that a single photodiode or phototransistor (light receiving element for one pixel) is used as the light receiving members SA to SG and SAU. However, these light receiving members can also be constituted by area sensors (two-dimensional sensors: light receiving element groups for a plurality of pixels) such as CCD sensors and CMOS sensors. In this case, the minimum number of pixels, pixel size, and pixel density of the area sensor are sufficient, and a very inexpensive area sensor can be used.

  The significance of using an area sensor as the light receiving member is as follows. That is, when a single photodiode or phototransistor is used, it is impossible to detect a scattered light component from the inspection object in a certain wide area only by pinpoint detection.

  Therefore, when a single photodiode or phototransistor is used as the light receiving member, a slight difference in intensity distribution of the scattered light component cannot be detected, and the accuracy of the surface inspection is not necessarily high.

  On the other hand, when an area sensor is used as the light receiving member, a two-dimensional intensity distribution of the scattered light component can be detected and stored as image information. And in each area sensor as each light receiving member SA-SG, SAU, it becomes possible to detect a crack and dirt with high precision by setting the above-mentioned reference information and limit information for every pixel.

  Reference information and limit information (judgment information) when using an area sensor include not only the light intensity in units of pixels, but also the difference value (distribution information) of the light intensity between pixels, the extent of the spread of scattered light components, etc. This information is also used.

  In this case, it is conceivable to determine whether the inspection object is good or bad by performing image analysis and matching the distribution pattern of the light intensity of the scattered light component. However, in the present embodiment, whether or not the inspection object is good or bad is determined by a simple method without performing advanced processing such as image analysis.

  For example, the degree of spread of the scattered light component is determined mainly by paying attention to the light intensity of the pixels in the outer peripheral portion of the area sensor, and the degree of scratches and dirt is determined as the degree of spread increases.

  Further, regarding the scattered light component due to the scratch, if the reduction rate of the light intensity of the scattered light component when going away from the inspection target in the X-axis direction is small, it is determined that the degree of the scratch is large. . Furthermore, with regard to the scattered light component caused by dirt, if the reduction rate of the light intensity of the scattered light component when going from the central pixel of the area sensor to the peripheral pixel is small, the degree of dirt is large. judge.

  As described above, various components such as the photosensitive drum 1 are incorporated into the image forming apparatus by optimally combining the various light guide members of the laser light, the various light collecting members of the scattered light component, and the various light receiving members. It is possible to inspect the surface of the part in a state as it is.

  5, 6, 11, and 12, only the light guide member and the light collecting member corresponding to the photosensitive drum are shown, but in the unit for inspecting the surface of other parts such as the intermediate transfer belt, Similar light guide members and light collecting members can be used.

  The present invention is not limited to each of the above-described embodiments. For example, the technology according to each of the above-described embodiments for surface inspection of various parts incorporated in an apparatus other than an image forming apparatus or a single article. It is also possible to apply ideas.

  Moreover, it is also possible to use a one-dimensional line sensor (linear sensor) instead of the light receiving members SA to SC that receive scattered light components caused by scratches. Furthermore, the inspection object may be irradiated with laser light (non-dispersed light beam) having a wavelength other than red laser light.

1 is a cross-sectional view illustrating a schematic configuration of an image forming apparatus in which a surface inspection apparatus is built in an embodiment of the present invention. FIG. 2 is a block diagram illustrating a configuration of a control system of the image forming apparatus in FIG. 1. It is a figure for demonstrating the irradiation method of the laser beam in said surface inspection apparatus. It is a figure which shows the basic composition of said surface inspection apparatus (it respond | corresponds to the damage | wound and dirt of a photosensitive drum). It is a figure for demonstrating the scattered light resulting from the stain | pollution | contamination of a test subject (photosensitive drum) and its light-receiving member. It is a figure for demonstrating the scattered light resulting from the surface roughness of a new test target object (photosensitive drum), and its light-receiving member. It is a figure for supplementarily explaining the deployment position etc. of a light receiving member. FIG. 3 is a diagram showing a basic configuration when inspecting the surface of an intermediate transfer belt. It is a flowchart which shows the outline | summary of a surface inspection process. 10 is a flowchart showing details of a flaw / dirt determination process in P5, P9, and P13 of FIG. 9; It is a figure which shows the structure of the surface inspection apparatus which concerns on the 2nd Embodiment of this invention (The 2nd light guide member and the 1st condensing member are used). It is a figure which shows the structure of the surface inspection apparatus which concerns on the 3rd Embodiment of this invention (The 3rd light guide member and the 2nd condensing member are used).

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Photosensitive drum 4 ... Intermediate transfer belt 5 ... Fixing device 5a ... Heating roller 5b ... Pressure belt 12-15 ... Laser-emitting member 21 ... CPU
22 ... Memory 22a ... EEPROM
SA, SAU, SB, SC, SD, SE, SF, SG ... light receiving member G, F ... condensing member Le ... condensing lens LGL ... light guide lens LP ... light guide pipe Mi ... mirror S1 ... regular reflection region S2 ... Scattered light region S3 caused by surface roughness Scattered light region STY caused by scratch Sscattered light region caused by dirt

Claims (11)

Irradiation means for collectively irradiating a non-dispersed light beam to a straight line on the surface of the inspection object without scanning;
A light receiving means for receiving a scattered light component of the reflected light of the non-dispersed light beam irradiated by the irradiation means;
Determination means for determining the state of the surface of the inspection object based on the light intensity of the scattered light component received by the light receiving means;
A surface inspection apparatus characterized by comprising:   The surface inspection apparatus according to claim 1, wherein the light receiving unit includes a single light receiving element.   The surface inspection apparatus according to claim 1, wherein a plurality of the light receiving means are provided according to a scattering region of the scattered light component.   2. The light receiving means is separately provided in a scattered region of scattered light components caused by scratches on the surface of the inspection object and a scattered region of scattered light components caused by dirt. The surface inspection apparatus in any one of -3.   The light receiving means is arranged in an overlapping region where a scattered region of scattered light components caused by scratches on the surface of the inspection object overlaps with a scattered region of scattered light components caused by dirt. Item 3. The surface inspection apparatus according to Item 1 or 2.   According to the shape of the scattering region of the scattered light component caused by the scratch on the surface of the inspection object, a plurality of the light receiving means are provided in the scattering region of the scattered light component caused by the scratch. The surface inspection apparatus in any one of Claims 1-4.   The determination means uses the determination information set in advance based on the light intensity of the scattered light component related to the various surface state inspection objects, and the same type of inspection object as the various surface state inspection objects. Determining the surface state of the inspection object that is actually the inspection object by determining the light intensity of the scattered light component related to the inspection object that is actually the inspection object. The surface inspection apparatus according to any one of claims 1 to 6.   The surface inspection apparatus according to claim 7, wherein the determination information is set for each of the plurality of light receiving units.   With respect to the light receiving means arranged in a plurality of scattered light component scattering regions caused by scratches on the surface of the inspection object, the light receiving means having a larger separation distance from the inspection object The surface inspection apparatus according to claim 8, wherein the surface inspection apparatus is set to determine that the degree of scratches is large with respect to the light intensity of the received scattered light component.   The surface inspection apparatus according to claim 1, wherein the determination unit determines whether or not the inspection object needs to be replaced based on a determination result of a surface state of the inspection object. An irradiation process for irradiating a non-dispersed light beam in a batch without scanning on a straight line on the surface of the inspection object;
A light receiving step for receiving a scattered light component of the reflected light of the non-dispersed light beam irradiated by the irradiation step;
A determination step of determining the state of the surface of the inspection object based on the light intensity of the scattered light component received by the light receiving step;
A surface inspection method characterized by comprising:

Images