JP5458934B2 - Inspection apparatus, image forming apparatus, inspection method, and inspection program - Google Patents

Description

  The present invention relates to an inspection apparatus, an image forming apparatus, an inspection method, and an inspection program for inspecting a belt that circulates and a sensor that outputs a voltage corresponding to the intensity of reflected light of light applied to the belt.

  Conventionally, in an electrophotographic image forming apparatus, an image quality adjustment toner pattern formed on a circulating belt such as an intermediate transfer belt is detected by an optical sensor, and image density adjustment is performed based on the detection result of the toner pattern. There is known a technique for performing image quality adjustment such as image adjustment and position adjustment (color shift adjustment). Belts and optical sensors used for image quality adjustment are components that are directly linked to image quality, so if the dirt is adhered by periodically inspecting its condition, the dirt is removed immediately, or It is required to take measures such as replacement of parts.

  From this point of view, the optical sensor can be cleaned by monitoring the amount of light emitted when the optical sensor is adjusted so that the amount of received light is constant when no toner pattern is formed on the intermediate transfer belt. It is proposed to inspect (for example, refer to Patent Document 1). As for belt dirt inspection, a technique has been proposed in which the detection signal of the optical sensor is input while the belt is driven once when the image forming apparatus is turned on, and the belt is inspected based on the input detection signal. (For example, refer to Patent Document 2).

  Inspection of belts and optical sensors used for image adjustment is an important process for maintaining image quality, but it is not a process directly related to image formation, so abnormalities such as contamination may occur. It is required to implement it efficiently and at appropriate timing. Here, when the power of the image forming apparatus is turned on, it is considered that there is a relatively high possibility that an abnormality has occurred in the belt or the optical sensor, for example, toner scattered during the previous image forming process is attached. For this reason, as described in Patent Document 2, it is considered effective to perform the inspection when the image forming apparatus is turned on as the inspection timing.

  However, in the case of inspecting the belt and the optical sensor when the image forming apparatus is turned on, the belt driving is started by the startup process until the belt operation is stabilized after that. As a result, first print delays and downtime frequently occur, which is inconvenient for the user.

  The present invention has been made in view of the above, and an object thereof is to provide an inspection apparatus, an image forming apparatus, an inspection method, and an inspection program that can reduce the first print delay and downtime caused by the inspection. .

  In order to solve the above-described problems and achieve the object, the inspection apparatus according to the present invention samples the output voltage of the sensor according to the reflected light intensity of the light irradiated on the surface of the circulating belt, and obtains sampling data. According to the conditions at the time of carrying out the test, the data generation means for generating the data, the determination means for comparing the sampling data generated by the data generation means with the determination reference value to determine whether the belt or the sensor is abnormal A first inspection mode in which the data generation means starts generating the sampling data after a predetermined waiting time has elapsed from the start of driving of the belt, and before the waiting time has elapsed from the start of driving of the belt. A determination reference value in which data generation means starts generating the sampling data and the determination means is relaxed compared to the first inspection mode. Characterized in that it and a test mode setting means for setting one of the second test mode for determining with.

  The image forming apparatus according to the present invention is conveyed by a circulating belt, a sensor that outputs a voltage corresponding to the reflected light intensity of light irradiated on the surface of the belt, and on or by the belt. An image forming means for forming an image on a recording sheet and an inspection apparatus according to the present invention are provided.

  Further, the inspection method according to the present invention generates sampling data by sampling the output voltage of the sensor according to the reflected light intensity of the light irradiated on the surface of the belt that circulates and moves the generated sampling data to the determination reference value. Compared to the above, it is an inspection method for determining the presence or absence of abnormality of the belt or the sensor, and according to the conditions at the time of performing the inspection, either the first inspection mode or the second inspection mode is set, When the first inspection mode is set, generation of the sampling data is started after a predetermined waiting time has elapsed from the start of driving of the belt, the generated sampling data is compared with a determination reference value, and the belt Alternatively, when it is determined whether there is an abnormality in the sensor and the second inspection mode is set, the support is performed before the standby time elapses from the start of driving the belt. The generation of pulling data is started, and the generated sampling data is compared with a determination reference value that is relaxed compared to when the first inspection mode is set to determine whether the belt or the sensor is abnormal. .

  An inspection program according to the present invention causes a computer to execute the inspection method according to the present invention.

  According to the present invention, either the first inspection mode or the second inspection mode is set according to the conditions at the time of performing the inspection. In the case of the second inspection mode, a predetermined time from the start of driving of the belt is set. Before the standby time elapses, the output voltage of the sensor is sampled to generate sampling data, and the generated sampling data is compared with a judgment reference value that is more relaxed than when the first inspection mode is set. Since the presence / absence is determined, when performing an inspection in a situation where there is a high possibility that an abnormality has occurred, an inspection in the first inspection mode is performed, and an inspection is performed in a state where the possibility that an abnormality has occurred is low In some cases, by performing the inspection in the second inspection mode, it is possible to reduce the first print delay and the downtime caused by the inspection.

FIG. 1 is a configuration diagram showing a schematic configuration of a color laser printer. FIG. 2 is a block diagram showing a hardware configuration of the control system of the color laser printer. FIG. 3 is a diagram showing the relationship between the toner pattern formed on the intermediate transfer belt and the waveform of the output voltage of the toner mark sensor. FIG. 4 shows how the waveform of the output voltage of the toner mark sensor when the surface of the intermediate transfer belt without a toner pattern is irradiated changes depending on the state of the intermediate transfer belt and the toner mark sensor. FIG. FIG. 5 is a functional block diagram showing a functional configuration for carrying out the inspection process. FIG. 6 is a flowchart showing a processing procedure by the inspection mode setting unit. FIG. 7 is a flowchart showing a series of inspection processing procedures when the normal inspection mode is set by the inspection mode setting unit. FIG. 8 is a flowchart showing a procedure of a series of inspection processes when the inspection mode setting unit sets the inspection mode after JAM processing. FIG. 9 is a flowchart illustrating a series of inspection processing procedures when the inspection mode with belt life determination is set by the inspection mode setting unit.

  Exemplary embodiments of an inspection apparatus, an image forming apparatus, an inspection method, and an inspection program according to the present invention are explained in detail below with reference to the accompanying drawings. The following embodiment is an example in which the present invention is applied to a color laser printer.

  FIG. 1 is a configuration diagram showing a schematic configuration of a color laser printer 1 according to the present embodiment. This color laser printer 1 is of an electrophotographic tandem type, and has four drum-like photosensitive drums 2Y (yellow), 2C (cyan), 2M (magenta), and 2K (black) as image carriers. The toner images formed by developing the electrostatic latent images of the toner images by the developing units 3Y, 3C, 3M, and 3K are sequentially transferred onto the intermediate transfer belt 5 as an intermediate medium by the transfer rollers 4Y, 4C, 4M, and 4K. Then, an indirect transfer method is adopted in which the image on the intermediate transfer belt 5 is collectively transferred by the secondary transfer roller 6 onto the recording paper P as a transfer body.

  The intermediate transfer belt 5 is an endless belt and is stretched by a plurality of rollers 10 to 13. The intermediate transfer belt 5 is driven by a transfer drive motor 21 (see FIG. 2) connected to any one of the rollers 10 to 13, and circulates in the direction of arrow D1 (sub-scanning direction) in FIG. On the upper side of the intermediate transfer belt 5, there are four photosensitive drums 2K, 2M, 2C, 2Y for the respective colors of black, magenta, cyan and yellow along the moving direction D1 of the intermediate transfer belt 5. Each is arranged. Further, a toner mark sensor 20 for detecting a toner pattern for image quality adjustment formed on the intermediate transfer belt 5 is disposed further downstream of the photosensitive drum 2Y in the moving direction D1 of the intermediate transfer belt 5. .

  The toner mark sensor 20 is a sensor that irradiates the surface of the intermediate transfer belt 5 with light, detects the reflected light, and outputs a voltage corresponding to the intensity of the reflected light. For example, the regular reflected light from the intermediate transfer belt 5 A regular reflection light sensor that detects diffusive light, a diffuse light sensor that detects diffuse light, or a reflective photosensor that can detect both regular reflection light and diffuse light is used.

  Around the photosensitive drums 2K, 2M, 2C, 2Y, charging devices 7K, 7M, 7C, 7Y, the developing units 3K, 3M, 3C, 3Y, the transfer rollers 4K, 4M, 4C, 4Y, Cleaning devices 8K, 8M, 8C, and 8Y constituted by blades, brushes, and the like, and static elimination devices 9K, 9M, 9C, and 9Y are provided, respectively.

  The primary transfer devices 4K, 4M, 4C, and 4Y are disposed to face the photosensitive drums 2K, 2M, 2C, and 2Y, respectively, with the intermediate transfer belt 5 interposed therebetween. That is, the intermediate transfer belt 5 circulates and moves between the primary transfer devices 4K, 4M, 4C, and 4Y and the photosensitive drums 2K, 2M, 2C, and 2Y.

  The photosensitive drums 2K, 2M, 2C, and 2Y are rotationally driven in the direction of the arrow D2 in FIG. 1, and at this time, the surfaces of the photosensitive drums 2K, 2M, 2C, and 2Y are predetermined by the charging devices 7K, 7M, 7C, and 7Y. Charged to the polarity of. Next, the charged surfaces of the photosensitive drums 2K, 2M, 2C, and 2Y are irradiated with laser light corresponding to image data from the light beam scanning device 16 that is an optical writing unit, so that the photosensitive drums 2K, 2M, and 2C are irradiated. , 2Y, an electrostatic latent image is formed. The electrostatic latent images formed in this manner are developed into toner images of respective colors by the developing units 3K, 3M, 3C, and 3Y, and are visualized.

  The developed black, magenta, cyan, and yellow toner images on the developed photosensitive drums 2K, 2M, 2C, and 2Y are sequentially superimposed on the surface of the intermediate transfer belt 5 by the action of the primary transfer devices 4K, 4M, 4C, and 4Y. In this state, the image is transferred and a full-color composite color image is formed.

  The photosensitive drums 2K, 2M, 2C, and 2Y are cleaned by the cleaning devices 8K, 8M, 8C, and 8Y after the toner images remaining on the photosensitive drums 2K, 2M, 2C, and 2Y are removed. , 9M, 9C, 9Y.

  The secondary transfer roller 6 is disposed to face the roller 12 with the intermediate transfer belt 5 interposed therebetween. A recording sheet P fed from a sheet feeding unit (not shown) is fed between the secondary transfer roller 6 and the intermediate transfer belt 5 at a predetermined timing. When the recording paper P is fed in the direction of arrow D3 in FIG. 1 between the secondary transfer roller 6 and the intermediate transfer belt 5, the composite color image carried on the intermediate transfer belt 5 is transferred to the secondary transfer roller 6. Are collectively transferred to the recording paper P.

  Thereafter, the composite color image on the recording paper P is fixed by heat and pressure by the fixing roller 14 and discharged onto a paper discharge tray (not shown). On the other hand, the transfer residual toner adhering to the surface of the intermediate transfer belt 5 after the transfer of the composite color image is removed by the cleaning device 15.

  FIG. 2 is a block diagram showing a hardware configuration of a control system of the color laser printer 1 according to the present embodiment. The control system shown in FIG. 2 includes a CPU 31, a RAM 32, a ROM 33, an IO control unit 34, a transfer drive motor I / F 35, a driver 36, and a detection IO unit 37.

  The CPU 31 comprehensively controls the overall operation of the color laser printer 1 including the reception of image data input from the external device 22 and the transmission / reception control of control commands. The RAM 32 is used as a work area when the CPU 31 executes various control programs to perform arithmetic processing, and the ROM 33 stores information such as various control programs executed by the CPU 31 and initial parameters. The IO control unit 34 controls input / output to each load 23 in the color laser printer 1.

  The CPU 31 is mutually connected to the RAM 32, the ROM 33, and the IO control unit 34 via a bus, and executes a control program stored in the ROM 33 by using the RAM 32 as a work area. Various operation controls such as a motor, a clutch, a solenoid, and a sensor for driving each load 23 are executed.

  The transfer drive motor I / F 35 is connected to the CPU 31 via a bus, and outputs a command signal that commands the drive frequency of the drive pulse signal to the driver 36 in response to a drive command from the CPU 31. The transfer driving motor 21 is driven to rotate in accordance with this frequency, and the transfer driving motor 21 is driven to rotate, whereby the intermediate transfer belt 5 shown in FIG. 1 is driven.

  The detection IO unit 37 is connected to the CPU 31 via a bus, outputs a control command from the CPU 31 to the toner mark sensor 20, and temporarily outputs information (output voltage) from the toner mark sensor 20 to the RAM 32. Store.

  In the color laser printer 1 according to this embodiment, the image quality adjustment processing is performed by the CPU 31 executing the image quality adjustment program stored in the ROM 33. In the image quality adjustment process, first, the intermediate transfer belt 5 is driven at a constant speed, and a toner pattern for image quality adjustment is formed on the intermediate transfer belt 5. Next, the toner mark sensor 20 is actuated to irradiate the intermediate transfer belt 5 on which the toner pattern is formed, detect the reflected light, and detect the position and formation of the toner pattern on the intermediate transfer belt 5. A change in the amount of received light according to the difference in reflectance from the position where the light is not applied is output as a voltage change. The output voltage from the toner mark sensor 20 is temporarily stored in the RAM 32. The CPU 31 uses the information stored in the RAM 32 to calculate the density and position of the toner pattern, and calculates correction parameters for density adjustment and position adjustment (color misregistration adjustment). This correction parameter is stored in the RAM 32 and used in an actual image forming operation.

  FIG. 3 is a diagram showing the relationship between the toner pattern formed on the intermediate transfer belt 5 and the waveform of the output voltage of the toner mark sensor 20. Here, as shown in FIG. 3A, toner patterns Y1, K1, and C1 for color misregistration adjustment are provided at three positions in the direction (main scanning direction) orthogonal to the moving direction (sub-scanning direction) of the intermediate transfer belt 5. , M1, Y2, K2, C2, and M2 are formed, and the toner patterns at the three positions are detected by the three detection units 20a, 20b, and 20c of the toner mark sensor 20, respectively. FIG. 3B shows a waveform of the output voltage output from the detection unit 20 a of the toner mark sensor 20.

  The toner mark sensor 20 adjusts the supply current to the toner mark sensor 20 so as to output the reference voltage Vsg when light is irradiated to a position where the toner pattern of the intermediate transfer belt 5 is not formed. (Offset adjustment). When the irradiation position of the light from the toner mark sensor 20 is applied to the toner patterns Y1, K1, C1, M1, Y2, K2, C2, and M2 with the movement of the intermediate transfer belt 5, the reflected light intensity is reduced, so that the toner The output voltage from the mark sensor 20 decreases and falls below the threshold voltage Vth. The CPU 31 specifies the positions of the toner patterns Y1, K1, C1, M1, Y2, K2, C2, and M2 on the intermediate transfer belt 5 from the waveform of the output voltage of the toner mark sensor 20, and Y, M, C, The correction parameter is calculated by calculating the color misregistration between K.

  Here, as shown in FIG. 3A, if there is dirt or scratches B on the intermediate transfer belt 5, the reflected light intensity decreases at the position where the dirt or scratches B are present. As shown, the output voltage of the toner mark sensor 20 may be lower than the threshold voltage Vth at this position. As a result, the CPU 31 misrecognizes that a toner pattern is formed at this position, and calculates a correction parameter according to the misrecognized position. On the contrary, it will be promoted. Further, not only when there is a partial stain or scratch B as shown in FIG. 3A, but also when there is a wide range of stain (filming) covering the entire surface of the intermediate transfer belt 5, or toner Even when dirt is attached to the mark sensor 20, the image quality adjustment may not be performed properly due to these factors.

  Therefore, in the color laser printer 1 according to the present embodiment, an inspection for inspecting whether there is an abnormality in the intermediate transfer belt 5 or the toner mark sensor 20 at a predetermined timing, such as when the power is turned on or when the operation is resumed after the jam processing. The processing is carried out. Specifically, the output voltage from the toner mark sensor 20 when the intermediate transfer belt 5 in which no toner pattern is formed is driven and the toner mark sensor 20 is operated to irradiate the surface of the intermediate belt 5 with light. And the sampling data is compared with a determination reference value to inspect whether the intermediate transfer belt 5 or the toner mark sensor 20 is abnormal. In the present embodiment, in particular, three inspection modes of a normal inspection mode, a post-JAM processing inspection mode, and an inspection mode with belt life determination described later are provided as inspection modes when performing this inspection processing. By selectively setting one of the inspection modes according to the conditions for performing the inspection process, an efficient inspection process can be performed.

  FIG. 4 is a diagram showing a waveform of the output voltage of the toner mark sensor 20 when light is irradiated on the surface of the intermediate transfer belt 5 in a state where no toner pattern is formed, and FIG. 4B is an output voltage waveform when the intermediate transfer belt 5 is partially soiled or scratched, and FIG. 4C is an output voltage waveform when the intermediate transfer belt 5 is filmed. FIG. 4D shows an output voltage waveform when the toner mark sensor 20 is contaminated, and FIG. 4E shows an output voltage waveform when the intermediate transfer belt 5 has a lifetime.

  When the intermediate transfer belt 5 does not have any abnormalities such as partial dirt, scratches or filming, and the toner mark sensor 20 itself has no dirt or abnormalities, the waveform of the output voltage of the toner mark sensor 20 is as shown in FIG. As shown in FIG. 4A, the waveform changes flatly around the reference voltage Vsg.

  When the intermediate transfer belt 5 is partially soiled or scratched, the waveform of the output voltage of the toner mark sensor 20 is for detecting the toner pattern at a position where the toner mark sensor 20 is soiled or scratched as shown in FIG. The waveform is lower than the threshold voltage Vth. Therefore, when the image quality adjustment process is performed using the intermediate transfer belt 5 in such a state, there is a risk that dirt and scratches on the intermediate transfer belt 5 may be erroneously recognized as a toner pattern as described above.

  Further, when filming has occurred on the intermediate transfer belt 5, the glossiness of the surface of the intermediate transfer belt 5 is lost, so that the output voltage of the toner mark sensor 20 as shown in FIG. Does not rise to the reference voltage Vsg and cannot function as the toner mark sensor 20.

  Further, when the toner mark sensor 20 is contaminated, the light from the toner mark sensor 20 diffuses and the amount of received light decreases, so that the output of the toner mark sensor 20 as shown in FIG. The voltage does not increase to the reference voltage Vsg, and the function as the toner mark sensor 20 cannot be performed.

  Further, when the intermediate transfer belt 5 has a lifetime, the glossiness of the surface varies due to deterioration with time, and the flatness is impaired due to deformation or the like. Therefore, the output voltage waveform of the toner mark sensor 20 is shown in FIG. As shown in (), it fluctuates up and down around the reference voltage Vsg and cannot be adjusted to the reference voltage Vsg.

  FIG. 5 is a functional block diagram showing a functional configuration for carrying out inspection processing in the color laser printer 1 according to the present embodiment. As shown in FIG. 5, the color laser printer 1 according to the present embodiment includes an inspection mode setting unit 101, a sensor control unit 102, and an offset adjustment unit 103 as functional components for performing the inspection process. An offset adjustment value storage unit 104, a determination unit 105, a determination reference value storage unit 106, and an inspection result output unit 107. Each of these units is realized by the CPU 31 executing an inspection program stored in the ROM 33, for example.

  The inspection mode setting unit 101 selectively sets one of the three inspection modes of the normal inspection mode, the inspection mode after JAM processing, and the inspection mode with belt life determination according to the conditions for performing the inspection processing. In the color laser printer 1 according to the present embodiment, the inspection process is performed when the power is turned on and when the operation is restored after the JAM process. If the elapsed time is less than or equal to a predetermined time (for example, one month), the inspection mode is set to the normal inspection mode, and if the elapsed time from the previous power-on exceeds the predetermined time (for example, one month) when the power is turned on The inspection mode is set to the inspection mode with belt life determination. Further, the inspection mode setting unit 101 sets the inspection mode to the inspection mode after JAM processing when the operation returns after the JAM processing.

  In the normal inspection mode, the toner mark sensor 20 is actuated by operating the toner mark sensor 20 almost simultaneously with the start of driving of the intermediate transfer belt 5, that is, without waiting for a predetermined waiting time from the start of driving of the intermediate transfer belt 5. Is output to the determination unit 105, and the determination unit 105 starts generating sampling data to be described later before a predetermined waiting time has elapsed from the start of driving of the intermediate transfer belt 5, and relaxed compared to other inspection modes. This is a mode (second inspection mode) in which determination is performed using the determined determination reference value. In this normal inspection mode, since the inspection is performed using the output voltage output from the toner mark sensor 20 before the movement of the intermediate transfer belt 5 is stabilized, the determination criterion in the determination unit 105 is described in detail later. The value is relaxed compared to other inspection modes, so that an abnormality in the output voltage of the toner mark sensor 20 due to the vibration of the intermediate transfer belt 5 is not erroneously determined as dirt. In the normal inspection mode, adjustment of the output voltage of the toner mark sensor 20 to the reference voltage Vsg (offset adjustment) is omitted, and the toner mark sensor 20 is operated using the previous offset adjustment value.

  When performing the inspection process when the color laser printer 1 is turned on, if the time has not passed since the last time the power was turned on, the intermediate transfer belt 5 and the toner mark sensor 20 may have an abnormality such as contamination. The property is considered to be relatively low. On the other hand, when the power is turned on when not much time has passed since the last power-on, it occurs most frequently as the timing for performing the inspection process. The occurrence of delay and downtime is a factor that makes the user feel dissatisfied. Therefore, when performing inspection processing at power-on when not much time has passed since the last power-on, priority is given to the quickness over the accuracy of the inspection, so select the normal inspection mode as the inspection mode, The first print delay and downtime caused by the inspection are reduced.

  In the inspection mode after JAM processing, after a predetermined waiting time has elapsed from the start of driving of the intermediate transfer belt 5, the toner mark sensor 20 is operated and the output voltage of the toner mark sensor 20 is input to the determination unit 105. This is a mode (first inspection mode) in which generation of sampling data, which will be described later, is started after a predetermined waiting time has elapsed from the start of driving of the intermediate transfer belt 5. In the post-JAM processing inspection mode, the inspection is performed using the output voltage output from the toner mark sensor 20 in a state where the movement of the intermediate transfer belt 5 is stabilized. Therefore, the influence of the vibration of the intermediate transfer belt 5 needs to be considered. Therefore, the determination reference value in the determination unit 105 is made stricter than in the normal inspection mode, thereby improving the inspection accuracy. Further, in the post-JAM processing inspection mode, after the offset adjustment of the toner mark sensor 20 is performed, the output voltage of the toner mark sensor 20 is input to the determination unit 105.

  When the operation is restored after JAM processing, the user may touch the intermediate transfer belt 5 or the toner mark sensor 20 during JAM processing, which is compared to when the power is turned on, which has not passed much time since the previous power-on. Thus, it is considered that there is a high possibility that the intermediate transfer belt 5 and the toner mark sensor 20 have an abnormality such as dirt adhesion. On the other hand, even if it takes some time for the inspection process to be performed when the operation returns after the JAM process, it is recognized as a part of the JAM process by the user, so that the user does not feel much dissatisfaction. Therefore, when performing inspection processing when returning to operation after JAM processing, accuracy is prioritized over speed of inspection. Therefore, the inspection mode after JAM processing is selected as the inspection mode, and accurate inspection is performed. I have to.

  In the inspection mode with belt life determination, the output voltage of the toner mark sensor 20 is determined by operating the toner mark sensor 20 after a predetermined waiting time has elapsed from the start of driving of the intermediate transfer belt 5 as in the inspection mode after JAM processing. This is a mode (first inspection mode) in which the determination unit 105 starts to generate sampling data, which will be described later, after a predetermined waiting time has elapsed from the start of driving of the intermediate transfer belt 5. As processing in the unit 105, processing for determining the life of the intermediate transfer belt 5 is added. In the inspection mode with belt life determination, after the offset adjustment of the toner mark sensor 20 is performed, the output voltage of the toner mark sensor 20 is input to the determination unit 105. Further, after the inspection is completed, If both the transfer belt 5 and the toner mark sensor 20 are clean and in a normal state, the image quality adjustment process described above is performed. In the inspection mode with belt life determination, the inspection is performed using the output voltage output from the toner mark sensor 20 in a state where the movement of the intermediate transfer belt 5 is stabilized, as in the inspection mode after JAM processing. The determination reference value in the determination unit 105 is made stricter than that in the normal inspection mode, thereby improving the inspection accuracy.

  When the power of the color laser printer 1 is turned on after a predetermined time (for example, one month) has elapsed since the previous power-on, the time that the power is left off is long, and the time since the last inspection process was performed Since the elapsed time is long, there is a high possibility that the intermediate transfer belt 5 and the toner mark sensor 20 have an abnormality such as dirt adhering during that time. On the other hand, the situation in which the color laser printer 1 is turned on after a predetermined time (for example, one month) has elapsed since the previous power-on does not occur frequently, and the inspection process performed in such a situation Even if it takes some time, it is unlikely that the user will be frustrated. In such a situation, there is a possibility that the glossiness of the surface of the intermediate transfer belt 5 varies due to deterioration with time, or the flatness is impaired due to deformation or the like. Therefore, when the inspection process is performed when the power is turned on after a predetermined time has elapsed since the previous power was turned on, accuracy is given priority over the speed of inspection, and the deterioration of the intermediate transfer belt 5 with time is also confirmed. Since it is necessary, the inspection mode with belt life determination is selected as the inspection mode so that the accurate inspection is performed and the life of the intermediate transfer belt 5 is also determined.

  Information on the inspection mode set by the inspection mode setting unit 101 is notified to the sensor control unit 102, the offset adjustment unit 103, and the determination unit 105, respectively.

  The sensor control unit 102 controls the operation of the toner mark sensor 20, and in particular, the output voltage from the toner mark sensor 20 is input to the determination unit 105 according to the inspection mode set by the inspection mode setting unit 101. Control the timing. That is, when the inspection mode is set to the normal inspection mode, the sensor control unit 102 operates the toner mark sensor 20 almost simultaneously with the start of driving of the intermediate transfer belt 5 and determines the output voltage of the toner mark sensor 20. 105 is input. In addition, when the inspection mode is set to the inspection mode after JAM processing or the inspection mode with belt life determination, the sensor control unit 102 detects the toner mark sensor 20 after a predetermined waiting time has elapsed from the start of driving of the intermediate transfer belt 5. After the offset adjustment by the offset adjustment unit 103 is completed, the output voltage of the toner mark sensor 20 is input to the determination unit 105.

  The offset adjustment unit 103 outputs the toner mark sensor 20 when the surface of the intermediate transfer belt 5 is irradiated with light when the inspection mode of the inspection process is set to the inspection mode after JAM processing or the inspection mode with belt life determination. Offset adjustment is performed to adjust the supply current to the toner mark sensor 20 so that the voltage becomes the reference voltage Vsg. The offset adjustment unit 103 stores the offset adjustment value (supply current offset value) in the offset adjustment value storage unit 104 every time the offset adjustment of the toner mark sensor 20 is performed. When the inspection mode of the inspection process is set to the normal inspection mode, the offset adjustment is not performed in the inspection process, and the previous offset adjustment value stored in the offset adjustment value storage unit 105 is used. The supply current to the toner mark sensor 20 is adjusted. The offset adjustment unit 103 also performs offset adjustment when performing image quality adjustment processing as described above.

  The determination unit 105 samples the output voltage of the toner mark sensor 20 to generate sampling data (sampling data generation unit), and compares the generated sampling data with the determination reference value stored in the determination reference value storage unit 106. Then, it is determined whether the intermediate transfer belt 5 and the toner mark sensor 20 are dirty (determination unit). Specifically, the determination unit 105 receives an input from the toner mark sensor 20 during one rotation of the intermediate transfer belt 5 after the input of the output voltage of the toner mark sensor 20 is started under the control of the sensor control unit 102. Sampling data is generated by sampling the output voltage at several hundred sampling points. That is, when the inspection mode is set to the normal inspection mode, the determination unit 105 samples and samples the output voltage input from the toner mark sensor 20 for one round of the belt almost simultaneously with the start of driving of the intermediate transfer belt 5. When data is generated and the inspection mode is set to the inspection mode after JAM processing or the inspection mode with belt life determination, it is input from the toner mark sensor 20 after a predetermined waiting time has elapsed from the start of driving of the intermediate transfer belt 5. Sampling data is generated by sampling the output voltage for one revolution of the belt. In addition, when the inspection mode is set to the normal inspection mode, the determination unit 105 generates sampling data from the output voltage of the toner mark sensor 20 whose supply current is adjusted by the previous offset adjustment value, and the inspection mode is When the inspection mode after JAM processing or the inspection mode with belt life determination is set, sampling data is generated from the output voltage of the toner mark sensor 20 in which the offset adjustment unit 103 has performed the offset adjustment.

  The determination unit 105 obtains the average value and the minimum value of the sampling data generated as described above, and compares the average value of the sampling data with the first determination reference value stored in the determination reference value storage unit 106. The minimum value of the sampling data is compared with the second determination reference value stored in the determination reference value storage unit 106 to determine whether the intermediate transfer belt 5 and the toner mark sensor 20 are dirty. Specifically, if the average value of the sampling data is within the range of the first determination reference value and the minimum value of the sampling data is greater than or equal to the second determination reference value, the intermediate transfer belt 5 is also marked with toner marks. It is determined that the sensor 20 is not dirty and is in a normal state. Further, if the average value of the sampling data is within the range of the first determination reference value and the minimum value of the sampling data is less than the second determination reference value, the intermediate transfer belt 5 may be partially soiled or damaged. It is determined that there is. If the average value of the sampling data is below the range of the first determination reference value, it is determined that filming (a wide range of dirt) has occurred on the intermediate transfer belt 5 or that the toner mark sensor 20 has dirt. If the average value of the sampling data exceeds the range of the first determination reference value, it is determined that an abnormality has occurred in the toner mark sensor 20 (including the drive circuit).

  Here, the first determination reference value is a determination reference value having a predetermined range defined by the upper limit value and the lower limit value. For the normal inspection mode, the inspection mode after JAM processing, and the inspection mode with belt life determination Are stored in the determination reference value storage unit 106. The first determination reference value for the normal inspection mode is a determination reference value that is more relaxed than the first determination reference value for the inspection mode after JAM processing and the inspection mode with belt life determination, that is, a determination reference having a wide range. It is a value. To illustrate specific values, for example, the first determination reference value for the inspection mode after JAM processing and the inspection mode with belt life determination has an upper limit value of the reference voltage Vsg + 0.5V and the reference voltage Vsg−0.5V. The first determination reference value for the normal inspection mode is a range in which the reference voltage Vsg + 0.5V is the upper limit value and the reference voltage Vsg−1.0V is the lower limit value, whereas the lower limit value is in the range. .

  Of course, the numerical values given here are merely examples, and may be set to optimum values according to various conditions. The difference between the first determination reference value for the normal inspection mode and the first determination reference value for the post-JAM inspection mode and the inspection mode with belt life determination is as described above from the start of driving of the intermediate transfer belt 5. What is necessary is just to determine according to the magnitude | size of the vibration of the intermediate transfer belt 5 until standby time passes. Thus, even in the normal inspection mode in which inspection is performed using sampling data generated immediately after the start of driving of the intermediate transfer belt 5, an abnormality in the output voltage of the toner mark sensor 20 due to vibration of the intermediate transfer belt 5 is erroneously determined as contamination. Inconvenience can be suppressed.

  The second determination reference value is a determination reference value for determining whether the intermediate transfer belt 5 is partially soiled or scratched by comparison with the minimum value of the sampling data. For example, the second determination reference value is a reference voltage Vsg-2. Set to .0V. Of course, the second determination reference value is not limited to the reference voltage Vsg−2.0 V exemplified here, but may be set to an optimum value according to various conditions. Similarly to the first determination reference value, two types of second determination reference values for the normal inspection mode, the post-JAM processing inspection mode, and the inspection mode with belt life determination may be provided. In the embodiment, it is common to all inspection modes.

  Further, when the inspection mode is set to the inspection mode with belt life determination, the determination unit 105 calculates the standard deviation of the sampling data, and the standard deviation of the sampling data is stored in the determination reference value storage unit 107. The life of the intermediate transfer belt 5 is determined in comparison with the third determination reference value. When the glossiness of the surface of the intermediate transfer belt 5 varies due to deterioration with time, or the flatness is impaired due to deformation or the like, the sampling data is not stable near the reference voltage Vsg, and the variation is large. Therefore, the determination unit 105 compares the standard deviation of the sampling data with the third determination reference value, and determines that the life of the intermediate transfer belt 5 is reached if the standard deviation of the sampling data exceeds the third determination reference value. .

  When the inspection mode is set to the inspection mode after JAM processing or the inspection mode with belt life determination, the determination unit 105 performs normal offset adjustment by the offset adjustment unit 103 in addition to the determination using the sampling data described above. It is also determined using information on whether or not the process was completed.

  The offset adjustment by the offset adjustment unit 103 is a process of adjusting the supply current to the toner mark sensor 20 so that the output voltage of the toner mark sensor 20 becomes the reference voltage Vsg as described above. If dirt is attached or filming occurs on the intermediate transfer belt 5, the output voltage does not rise to the reference voltage Vsg even if the supply current to the toner mark sensor 20 is increased to the upper limit value, and offset adjustment is performed. May not finish normally. In this case, the offset adjustment unit 103 notifies the determination unit 105 that the offset adjustment cannot be normally terminated due to the offset upper limit error. Further, if an abnormality occurs in the toner mark sensor 20 (including the drive circuit), the output voltage of the toner mark sensor 20 is fixed at a value exceeding the reference voltage Vsg, and the supply current to the toner mark sensor 20 In some cases, the output voltage does not decrease even if the offset is reduced, and offset adjustment cannot be completed normally. In this case, the offset adjustment unit 103 notifies the determination unit 105 that the offset adjustment cannot be normally terminated due to the offset lower limit error.

  If there is a notification from the offset adjustment unit 103 that the offset adjustment could not be completed normally due to the offset upper limit error, the determination unit 105 is contaminated with the toner mark sensor 20 or filmed on the intermediate transfer belt 5. Is determined to have occurred. Further, when the determination unit 105 receives a notification from the offset adjustment unit 103 that the offset adjustment has not been completed normally due to the offset lower limit error, an abnormality has occurred in the toner mark sensor 20 (including the drive circuit). judge.

  The inspection result output unit 107 outputs the result of determination by the determination unit 105 as an inspection result. Specifically, the inspection result output unit 107 displays the result of determination by the determination unit 105 on a display device such as an operation panel of the color laser printer 1 to notify the user of the inspection result. In addition, when the color laser printer 1 is provided with a speaker, the result of determination by the determination unit 105 may be output from the speaker to notify the user of the inspection result. Further, the result of determination by the determination unit 105 may be notified to the maintenance service provider via the telecommunication line, and the inspection result may be notified to the maintenance service provider together with the notification to the user. .

  Hereinafter, specific examples of inspection processing characteristic of the color laser printer 1 according to the present embodiment will be described with reference to the flowcharts of FIGS. 6 is a flowchart showing a processing procedure by the inspection mode setting unit 101, and FIG. 7 is a flowchart showing a series of inspection processing procedures when the normal inspection mode is set by the inspection mode setting unit 101. 8 is a flowchart showing a series of inspection processing procedures when the inspection mode setting unit 101 sets the inspection mode after JAM processing. FIG. 9 shows the belt life determination by the inspection mode setting unit 101. It is the flowchart which showed the procedure of a series of test | inspection processes when attachment inspection mode is set.

  First, the procedure for setting the inspection mode will be described with reference to FIG. The flowchart of FIG. 6 is started when the color laser printer 1 according to the present embodiment is started up. When the start-up of the color laser printer 1 is detected, the inspection mode setting unit 101 first determines whether the start-up of the color laser printer 1 is a start-up by turning on the power (step S101). The determination in step S101 can be performed, for example, by allowing a power ON signal to be input to the inspection mode setting unit 101 when the power is turned ON.

  When the color laser printer 1 is started up when the power is turned on (step S101: YES), the inspection mode setting unit 101 next determines whether or not a predetermined time (for example, one month) has elapsed since the previous power on. Is determined (step S102). The determination in step S102 is performed by, for example, providing a timer that counts the elapsed time from power ON and determining from the count value of the timer, or storing time information at the time of previous power ON and the current time It can be implemented by a method of acquiring time information when the power is turned on and judging from the difference between these time information.

  Here, when the predetermined time has not elapsed since the previous power ON (step S102: NO), the inspection mode setting unit 101 sets the inspection mode to the normal inspection mode (step S104). On the other hand, when the predetermined time has passed since the previous power ON (step S102: YES), the inspection mode setting unit 101 sets the inspection mode to the inspection mode with belt life determination (step S105).

  If the color laser printer 1 is not started up by turning on the power (step S101: NO), the inspection mode setting unit 101 determines whether it is started up by returning the operation after JAM processing (step S103). ). The determination in step S103 can be performed, for example, by inputting a signal of a cover sensor that detects opening / closing of the cover of the color laser printer 1 to the inspection mode setting unit 101.

  Here, when the start-up of the color laser printer 1 is the start-up by the operation return after the JAM processing (step S103: YES), the inspection mode setting unit 101 sets the inspection mode to the inspection mode after JAM processing (step S103). S106). On the other hand, when the start-up of the color laser printer 1 is not the start-up by the operation return after the JAM process (step S103: NO), the inspection mode setting unit 101 ends the process without setting the inspection mode. In this case, the inspection process is not performed.

  Next, with reference to FIG. 7, a series of inspection processing procedures when the inspection mode is set to the normal inspection mode will be described. When the inspection mode is set to the normal inspection mode, first, the offset adjustment unit 103 adjusts the supply current to the toner mark sensor 20 using the previous offset adjustment value stored in the offset adjustment value storage unit 104. (Step S201).

  Next, the sensor control unit 102 operates the toner mark sensor 20 almost simultaneously with the start of driving of the intermediate transfer belt 5, and inputs the output voltage of the toner mark sensor 20 to the determination unit 105 (step S202).

  Next, the determination unit 105 samples the output voltage input from the toner mark sensor 20 during one rotation of the intermediate transfer belt 5 at several hundred sampling points to generate sampling data (step S203). The determination unit 105 first determines whether or not the average value of the sampling data is within the range of the reference voltage Vsg + 0.5V to the reference voltage Vsg−1.0V, that is, the average value of the sampling data is the first value for the normal inspection mode. It is determined whether it is within the range of the determination reference value (step S204).

  Here, when the average value of the sampling data is within the range of the reference voltage Vsg + 0.5 V to the reference voltage Vsg−1.0 V (step S204: YES), the determination unit 105 next determines that the minimum value of the sampling data is the reference value. It is determined whether or not the voltage is less than Vsg−2.0 V, that is, whether or not the minimum value of the sampling data is less than the second determination reference value (step S205). When the minimum value of the sampling data is not less than the reference voltage Vsg−2.0 V (step S205: NO), the determination unit 105 is in a normal state in which neither the intermediate transfer belt 5 nor the toner mark sensor 20 is contaminated. (Step S207). On the other hand, if the minimum value of the sampling data is less than the reference voltage Vsg−2.0 V (step S205: YES), the determination unit 105 determines that the intermediate transfer belt 5 is partially soiled or scratched ( Step S208).

  When the average value of the sampling data is not within the range of the reference voltage Vsg + 0.5V to the reference voltage Vsg−1.0V (step S204: NO), the determination unit 105 next determines that the average value of the sampling data is It is determined whether or not the reference voltage Vsg + 0.5V is exceeded, that is, whether the average value of the sampling data exceeds the upper limit value of the first determination reference value for the normal inspection mode (step S206). When the average value of the sampling data exceeds the reference voltage Vsg + 0.5 V (step S206: YES), the determination unit 105 determines that an abnormality has occurred in the toner mark sensor 20 (including the drive circuit). Determination is made (step S209). On the other hand, when the average value of the sampling data does not exceed the reference voltage Vsg + 0.5V, that is, when the average value of the sampling data is below the lower limit value of the first determination reference value for the normal inspection mode (step S206: NO) ) Determines that the toner mark sensor 20 is contaminated or the intermediate transfer belt 5 has filming (step S210).

  Thereafter, the sensor control unit 102 stops the operation of the toner mark sensor 20 (step S211), and the inspection process in the normal inspection mode ends.

  In the inspection processing in the normal inspection mode, as described above, the toner mark sensor 20 is activated and inspection is started almost simultaneously with the start of driving of the intermediate transfer belt 5, and offset adjustment of the toner mark sensor 20 is not performed. The time required for the inspection is greatly reduced. Therefore, the first print delay and downtime caused by the inspection can be greatly reduced by performing the inspection process in the normal inspection mode at the time of power-on when not much time has passed since the previous power-on. it can. In addition, when the inspection is started by operating the toner mark sensor 20 almost simultaneously with the start of the driving of the intermediate transfer belt 5, there is a concern about the influence of the vibration of the intermediate transfer belt 5, but in the normal inspection mode, other inspections are performed. Since the contamination determination is performed using the determination reference value that is relaxed compared to the mode, it is possible to suppress the inconvenience of erroneous determination due to the influence of the vibration of the intermediate transfer belt 5, and a certain degree of inspection accuracy. Can be secured.

  Next, with reference to FIG. 8, a series of inspection processing procedures when the inspection mode is set to the inspection mode after JAM processing will be described. When the inspection mode is set to the inspection mode after JAM processing, first, after the driving of the intermediate transfer belt 5 is started (step S301), the offset adjustment unit 103 performs offset adjustment of the toner mark sensor 20 (step S301). S302).

  Next, the determination unit 105 determines whether or not the offset adjustment of the toner mark sensor 20 by the offset adjustment unit 103 has ended normally (step S303). If the offset adjustment of the toner mark sensor 20 by the offset adjustment unit 103 has been completed normally (step S303: YES), the sensor control unit 102 then performs a predetermined standby time from the start of driving of the intermediate transfer belt 5. (Step S304), and when a predetermined waiting time has elapsed from the start of driving of the intermediate transfer belt 5 (step S304: YES), the toner mark sensor 20 is operated to thereby detect the toner mark sensor. 20 output voltages are input to the determination unit 105 (step S305).

  Next, the determination unit 105 samples the output voltage input from the toner mark sensor 20 during one rotation of the intermediate transfer belt 5 at several hundred sampling points to generate sampling data (step S306). The determination unit 105 first determines whether or not the average value of the sampling data is within the range of the reference voltage Vsg + 0.5V to the reference voltage Vsg−0.5V, that is, the average value of the sampling data is for the inspection mode after JAM processing. It is determined whether it is within the range of the first determination reference value (step S307).

  Here, when the average value of the sampling data is within the range of the reference voltage Vsg + 0.5V to the reference voltage Vsg−0.5V (step S307: YES), the determination unit 105 next determines that the minimum value of the sampling data is the reference value. It is determined whether or not the voltage is less than Vsg−2.0 V, that is, whether or not the minimum value of the sampling data is less than the second determination reference value (step S308). If the minimum value of the sampling data is not less than the reference voltage Vsg−2.0 V (step S308: NO), the determination unit 105 is normal with no contamination on the intermediate transfer belt 5 and the toner mark sensor 20. (Step S311). On the other hand, when the minimum value of the sampling data is less than the reference voltage Vsg−2.0 V (step S308: YES), the determination unit 105 determines that the intermediate transfer belt 5 is partially soiled or scratched ( Step S312).

  When the average value of the sampling data is not within the range of the reference voltage Vsg + 0.5V to the reference voltage Vsg−0.5V (step S307: NO), the determination unit 105 next determines the average value of the sampling data. It is determined whether or not the reference voltage Vsg + 0.5V is exceeded, that is, whether the average value of the sampling data exceeds the upper limit value of the first determination reference value for the post-JAM inspection mode (step S309). If the average value of the sampling data exceeds the reference voltage Vsg + 0.5 V (step S309: YES), the determination unit 105 determines that an abnormality has occurred in the toner mark sensor 20 (including the drive circuit). Determination is made (step S313). On the other hand, when the average value of the sampling data does not exceed the reference voltage Vsg + 0.5V, that is, when the average value of the sampling data is below the lower limit value of the first determination reference value for the post-JAM inspection mode (step S309). : NO), the determination unit 105 determines that the toner mark sensor 20 is contaminated or the intermediate transfer belt 5 is filmed (step S314).

Further, when the offset adjustment of the toner mark sensor 20 by the offset adjustment unit 103 has not ended normally (step S303: NO), the determination unit 105 next determines that the factor that the offset adjustment does not end normally is the offset upper limit. It is determined whether or not an error has occurred (step S310). If the offset adjustment is not normally completed due to an offset upper limit error (step S310: YES), the determination unit 105 is contaminated with the toner mark sensor 20 or filmed on the intermediate transfer belt 5. Is determined to have occurred (step S315). On the other hand, when the offset adjustment is not normally terminated due to the offset upper limit error, that is, when the offset adjustment is not normally terminated due to the offset lower limit error (step S310: NO), the determination unit 105 performs the toner mark sensor. 20 (including the drive circuit) is determined to be abnormal (step S316).

  Thereafter, the sensor control unit 102 stops the operation of the toner mark sensor 20 (step S317), and the inspection processing in the post-JAM processing inspection mode ends.

  In the inspection process in the inspection mode after JAM processing, as described above, the toner mark sensor 20 is activated to start inspection after a predetermined waiting time has elapsed after the driving of the intermediate transfer belt 5 is started, and the toner is started. Since the offset adjustment of the mark sensor 20 is performed, the inspection can be performed with high accuracy.

  Next, with reference to FIG. 9, a series of inspection processing procedures when the inspection mode is set to the inspection mode with belt life determination will be described. When the inspection mode is set to the inspection mode with belt life determination, first, after the driving of the intermediate transfer belt 5 is started (step S401), the offset adjusting unit 103 performs the offset adjustment of the toner mark sensor 20 ( Step S402).

  Next, the determination unit 105 determines whether or not the offset adjustment of the toner mark sensor 20 by the offset adjustment unit 103 has ended normally (step S403). If the offset adjustment of the toner mark sensor 20 by the offset adjustment unit 103 has been completed normally (step S403: YES), the sensor control unit 102 then performs a predetermined standby time from the start of driving of the intermediate transfer belt 5. (Step S404), and when a predetermined waiting time has elapsed from the start of driving of the intermediate transfer belt 5 (step S404: YES), the toner mark sensor 20 is operated to set the toner mark sensor. The output voltage of 20 is input to the determination unit 105 (step S405).

  Next, the determination unit 105 samples the output voltage input from the toner mark sensor 20 during one rotation of the intermediate transfer belt 5 at several hundred sampling points to generate sampling data (step S406). Then, the determination unit 105 first calculates the standard deviation of the sampling data (step S407), and determines whether or not the calculated standard deviation value exceeds a predetermined value (third determination reference value) (step S407). S408).

  Here, if the value of the standard deviation of the sampling data is equal to or smaller than a predetermined value (third determination reference value) (step S408: NO), the determination unit 105 next determines that the average value of the sampling data is the reference voltage Vsg + 0. It is determined whether or not it is within the range of 5V to the reference voltage Vsg−0.5V, that is, whether or not the average value of the sampling data is within the range of the first determination reference value for the inspection mode with belt life determination (step S409). ).

  Here, when the average value of the sampling data is within the range of the reference voltage Vsg + 0.5V to the reference voltage Vsg−0.5V (step S409: YES), the determination unit 105 then determines that the minimum value of the sampling data is the reference value. It is determined whether or not the voltage is less than Vsg−2.0 V, that is, whether or not the minimum value of the sampling data is less than the second determination reference value (step S410). If the minimum value of the sampling data is not less than the reference voltage Vsg−2.0 V (step S410: NO), the determination unit 105 is in a normal state in which neither the intermediate transfer belt 5 nor the toner mark sensor 20 is contaminated. Is determined (step S413), and the image quality adjustment process is performed following the inspection process (step S420). On the other hand, when the minimum value of the sampling data is less than the reference voltage Vsg−2.0 V (step S410: YES), the determination unit 105 determines that the intermediate transfer belt 5 is partially soiled or scratched ( Step S414).

  When the average value of the sampling data is not within the range of the reference voltage Vsg + 0.5V to the reference voltage Vsg−0.5V (step S409: NO), the determination unit 105 next determines the average value of the sampling data. It is determined whether or not the reference voltage Vsg + 0.5V is exceeded, that is, whether the average value of the sampling data exceeds the upper limit value of the first determination reference value for the inspection mode with belt life determination (step S411). When the average value of the sampling data exceeds the reference voltage Vsg + 0.5 V (step S411: YES), the determination unit 105 determines that an abnormality has occurred in the toner mark sensor 20 (including the drive circuit). Determination is made (step S415). On the other hand, when the average value of the sampling data does not exceed the reference voltage Vsg + 0.5V, that is, when the average value of the sampling data is below the lower limit value of the first determination reference value for the inspection mode with belt life determination (step) In S411: NO), the determination unit 105 determines that the toner mark sensor 20 is contaminated or filming has occurred on the intermediate transfer belt 5 (step S416).

  If the standard deviation value of the sampling data exceeds a predetermined value (third determination reference value) (step S408: YES), the determination unit 105 determines that the life of the intermediate transfer belt 5 is the life (step S408). S417).

When the offset adjustment of the toner mark sensor 20 by the offset adjustment unit 103 has not been completed normally (step S403: NO), the determination unit 105 next determines that the factor that the offset adjustment does not end normally is the offset upper limit. It is determined whether or not it is due to an error (step S412). If the offset adjustment is not normally completed due to an offset upper limit error (step S412: YES), the determination unit 105 is contaminated with the toner mark sensor 20 or filmed on the intermediate transfer belt 5. Is determined to have occurred (step S418). On the other hand, when the offset adjustment is not normally terminated due to the offset upper limit error, that is, when the offset adjustment is not normally terminated due to the offset lower limit error (step S412: NO), the determination unit 105 performs the toner mark sensor. 20 (including the drive circuit) is determined to be abnormal (step S419).

  Thereafter, the sensor control unit 102 stops the operation of the toner mark sensor 20 (step S421), and the inspection process in the inspection mode with belt life determination ends.

  In the inspection process in the inspection mode with the belt life determination, as described above, the toner mark sensor 20 is activated and the inspection is started after a predetermined waiting time has elapsed after the driving of the intermediate transfer belt 5 is started. Since the offset adjustment of the toner mark sensor 20 is performed, the inspection can be performed with high accuracy as in the inspection mode after JAM processing. In addition, since the life of the intermediate transfer belt 5 is determined simultaneously with the inspection, it is possible to prompt the user to replace the intermediate transfer belt 5 when the intermediate transfer belt 5 is deteriorated with time. Further, when there is no abnormality in the intermediate transfer belt 5 and the toner mark sensor 20, the image quality adjustment process is continuously performed. Therefore, the image adjustment process can be performed using the toner mark sensor 20 in which the offset adjustment has already been completed. Image adjustment processing can be performed efficiently.

  As described above in detail with specific examples, the color laser printer 1 according to the present embodiment includes a normal inspection mode in which inspection can be performed in a short time as an inspection mode for inspection processing, and a high inspection mode. It has an inspection mode after JAM processing that can perform accurate inspection, and an inspection mode with belt life determination that can also determine the life of the intermediate transfer belt 5 together with high-accuracy inspection. When the power is turned on, the inspection process in the normal inspection mode is performed when the power is turned on, and the inspection process is performed in the inspection mode after the JAM process when the operation is resumed after the JAM process. When the power is turned on after one month), the inspection process is performed in the inspection mode with belt life determination. As described above, according to the color laser printer 1 according to the present embodiment, when the operation is restored after the JAM processing, which is highly likely to be abnormal, depending on the conditions for performing the inspection processing, or when the power is turned on last time. If the inspection is performed when the power is turned on after a predetermined time (for example, one month) has elapsed, a highly accurate inspection is performed in the inspection mode after JAM processing or the inspection mode with belt life determination (first inspection mode), When inspection is performed at power-on when not much time has passed since the previous power-on, which is unlikely to cause an abnormality. Perform an inspection in the normal inspection mode (second inspection mode). Therefore, it is possible to reduce the first print delay and downtime caused by the inspection.

  In the normal inspection mode, the time required for inspection is shortened by operating the toner mark sensor 20 to start generation of sampling data almost simultaneously with the start of driving of the intermediate transfer belt 5. Although there is a concern about the influence of the vibration of the belt 5, in the normal inspection mode, the presence / absence of an abnormality is determined using a judgment reference value that is relaxed compared to other inspection modes. The inconvenience of making an erroneous determination due to the influence of vibration can be suppressed. The normal inspection mode is a mode that is selected when inspection is performed in a situation where there is a low possibility that an abnormality has occurred. In a situation where there is a high possibility that an abnormality has occurred, an inspection mode after JAM processing and a belt life determination are included. Since the inspection is performed in the inspection mode, it is rare that a serious abnormality is detected during the inspection in the normal inspection mode. Therefore, even if the determination reference value used for determining whether there is an abnormality when the inspection is performed in the normal inspection mode, a serious abnormality is not missed. That is, in the normal inspection mode, the presence / absence of an abnormality may be determined using a criterion value that is relaxed as compared with the case of other inspection modes.

  Further, according to the color laser printer 1 according to the present embodiment, the determination unit 105 compares the average value of the sampling data with the first determination reference value, and sets the minimum value of the sampling data to the second determination reference value. Compared to the above, the presence / absence of abnormality of the intermediate transfer belt 5 and the toner mark sensor 20 is determined. Therefore, it is possible to determine what kind of abnormality has occurred and conduct a detailed inspection. can do.

  As described above, the inspection process in the color laser printer 1 according to the present embodiment is realized by executing an inspection program by the CPU 31 provided in the color laser printer 1. The inspection program executed by the CPU 31 is provided by being incorporated in advance in, for example, the ROM 33 provided in the color laser printer 1. The inspection program executed by the CPU 31 is an installable or executable file and can be read by a computer such as a CD-ROM, a flexible disk (FD), a CD-R, a DVD (Digital Versatile Disk). You may comprise so that it may record and provide on a recording medium. Further, the inspection program executed by the CPU 31 may be stored on a computer connected to a network such as the Internet and provided by being downloaded via the network. Further, the inspection program executed by the CPU 31 may be provided or distributed via a network such as the Internet.

  The inspection program executed by the CPU 31 includes the above-described units (inspection mode setting unit 101, sensor control unit 102, offset adjustment unit 103, offset adjustment value storage unit 104, determination unit 105, determination reference value storage unit 106, and inspection result output. Unit 107), and the actual hardware includes a CPU (processor) 31 that reads out and executes an inspection program from, for example, the ROM 33, and loads the above-described units onto the main storage device (RAM 32). Inspection mode setting unit 101, sensor control unit 102, offset adjustment unit 103, offset adjustment value storage unit 104, determination unit 105, determination reference value storage unit 106, and inspection result output unit 107 are generated on the main storage device. It has become.

  Note that the present invention is not limited to the above-described embodiments as they are, and can be embodied by modifying the constituent elements without departing from the scope of the invention in the implementation stage. For example, the embodiment described above is an example in which the present invention is applied to an indirect transfer type color laser printer 1, but the present invention is not limited to the indirect transfer type color laser printer 1, and a belt that circulates and its The present invention can be applied to various types of image forming apparatuses having an optical sensor that detects reflected light by irradiating the surface of the belt with light. In addition to an image forming apparatus, the apparatus has a belt that circulates and an optical sensor that detects reflected light by irradiating light on the surface of the belt, and inspection of the belt and the optical sensor is necessary. The present invention can be effectively applied to any device.

DESCRIPTION OF SYMBOLS 1 Color laser printer 5 Intermediate transfer belt 20 Toner mark sensor 101 Inspection mode setting part 102 Sensor control part 103 Offset adjustment part 104 Offset adjustment value memory | storage part 105 Judgment part 106 Judgment reference value memory | storage part 107 Inspection result output part

JP 2005-221523 A JP 2008-207955 A

Claims (11)

Data generating means for sampling the output voltage of the sensor according to the reflected light intensity of the light irradiated on the surface of the circulating belt, and generating sampling data;
A determination unit that compares the sampling data generated by the data generation unit with a determination reference value to determine whether the belt or the sensor is abnormal;
Depending on the conditions at the time of inspection, the data generating means starts generating the sampling data after a predetermined waiting time has elapsed from the start of driving of the belt, and from the start of driving of the belt The second inspection mode in which the data generation means starts generating the sampling data before the standby time elapses, and the determination means makes a determination using a determination reference value that is more relaxed than the first inspection mode. And an inspection mode setting means for setting any of the above.   The determination means compares the average value of the sampling data with a first determination reference value having a predetermined range, compares the minimum value of the sampling data with a second determination reference value, and calculates the average value of the sampling data. Is within the range of the first determination reference value and the minimum value of the sampling data is equal to or greater than the second determination reference value, it is determined that there is no abnormality in the belt and the sensor, and the sampling If the average value of the data is within the range of the first determination reference value and the minimum value of the sampling data is less than the second determination reference value, the belt is partially soiled or scratched. If the average value of the sampling data is below the range of the first determination reference value, the belt is extensively soiled or the sensor is soiled. The method according to claim 1, wherein if the average value of the sampling data exceeds a range of the first determination reference value, it is determined that an abnormality has occurred in the sensor. Inspection device.   The determination means, when the second inspection mode is set, determines a determination reference value having a wide range as the first determination reference value as compared with the case where the first inspection mode is set. The inspection apparatus according to claim 2, wherein the inspection apparatus is used.   The difference between the determination reference value used by the determination unit when the first inspection mode is set and the determination reference value used by the determination unit when the second inspection mode is set is the waiting time. The inspection apparatus according to claim 1, wherein the inspection apparatus is determined based on a magnitude of vibration of the belt during a period of time. Offset adjusting means for performing offset adjustment for adjusting a supply current to the sensor so that an output voltage of the sensor when the surface of the belt is irradiated with light becomes a predetermined value;
Further comprising storage means for storing an offset adjustment value when the offset adjustment means performed the offset adjustment at the previous inspection,
When the first inspection mode is set, the data generation unit generates the sampling data by sampling the output voltage of the sensor that has been offset adjusted by the offset adjustment unit, When the inspection mode is set, the sampling data is generated by sampling the output voltage of the sensor whose supply current is adjusted by the offset adjustment value at the previous inspection stored in the storage means. The inspection apparatus according to any one of claims 1 to 4.   When the first inspection mode is set, the determination unit compares the standard deviation of the sampling data with a third determination reference value, and the standard deviation of the sampling data is the third determination reference value. The inspection apparatus according to any one of claims 1 to 5, wherein the belt life is determined to exceed the belt life. A circulating belt,
A sensor that outputs a voltage corresponding to the reflected light intensity of the light irradiated on the surface of the belt;
An image forming means for forming an image on the belt or on a recording sheet conveyed by the belt;
An image forming apparatus comprising: the inspection apparatus according to claim 1. Further comprising image quality adjusting means for adjusting image quality based on a detection result of a pattern formed on the surface of the belt;
The image forming apparatus according to claim 7, wherein the sensor is a sensor used for detecting the pattern. The inspection apparatus performs an inspection when the image forming apparatus is turned on and when the operation is restored after the jam processing.
The inspection mode setting means sets the second inspection mode when the image forming apparatus is turned on and when the inspection is performed when the elapsed time from the previous power on is a predetermined time or less. The first inspection mode is set when an inspection is performed when the power is turned on and the elapsed time from the previous power-on exceeds the predetermined time, or when an inspection is performed when the operation is restored after jam processing. The image forming apparatus according to claim 7, wherein: The output voltage of the sensor according to the reflected light intensity of the light irradiated on the surface of the circulating belt is sampled to generate sampling data, and the generated sampling data is compared with the determination reference value, An inspection method for determining whether there is an abnormality,
Depending on the conditions at the time of inspection, set either the first inspection mode or the second inspection mode,
When the first inspection mode is set, generation of the sampling data is started after a predetermined standby time has elapsed from the start of driving of the belt, the generated sampling data is compared with a determination reference value, Determine whether there is an abnormality in the belt or the sensor,
When the second inspection mode is set, generation of the sampling data is started before the standby time elapses from the start of driving the belt, and the generated sampling data is set from the time of setting the first inspection mode. And comparing with a relaxed determination reference value to determine whether the belt or the sensor is abnormal.   An inspection program for causing a computer to execute the inspection method according to claim 10.

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