JP2012252144A - Faulty driving section determination device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To determine, when a faulty driving section is determined among a plurality of driving sections (driving parts), the faulty driving section quickly and easily.SOLUTION: A faulty driving section determination device comprises a plurality of driving sections, and is used in a processing unit that conducts a predetermined process by driving and controlling the driving sections. A CPU 101 determines a failed driving section among the plurality of driving sections as a faulty driving section by receiving an OR signal produced by ORing operation status signals showing the operation status of the plurality of driving sections. The CPU detects the progress stage of the predetermined process and temporarily stops the plurality of driving sections when the OR signal changes to an error. The CPU, by referring to a table having the order of the plurality of driving sections to be driven according to the progress stage prescribed therein as priorities, sequentially drives and controls the driving sections in the order of the priorities. When the OR signal changes to an error, the CPU determines the driving section that has driven immediately before the OR signal changed to the error, as a faulty driving section.

Description

  The present invention relates to a failure drive unit identification device for identifying which of a plurality of drive units is a failure drive unit, and more particularly, to identify a failure drive unit in an image forming apparatus having a plurality of drive units. The present invention relates to a failure drive unit identification device.

  In recent years, colorization has progressed in image forming apparatuses, and so-called tandem type image forming apparatuses are increasing. In such an image forming apparatus, the number of drive parts (for example, motors, solenoids, clutches) that are constituent parts inevitably increases. Further, in the tandem type image forming apparatus, the power consumption tends to increase, and a plurality of heat dissipating electric fans which are one of the driving parts are required.

  If the image forming apparatus is operated in a state where an abnormality such as a failure has occurred in these driving components (including the electric fan), not only does the image forming apparatus not operate normally, but the safety of the image forming apparatus itself is increased. It can be damaged. For this reason, it is performed to detect whether or not the drive components including the electric fan are operating normally. For this reason, what outputs the operation detection signal which shows the presence or absence of the operation abnormality is used for a drive component.

  Incidentally, as described above, in the image forming apparatus, since the number of driving parts as its constituent parts has increased, the number of operation detection signals has also increased, and in recent years it has become enormous.

  In order to cope with an increase in the number of motion detection signals, that is, to reduce the load on the processing device by substantially suppressing the number of motion detection signals, for example, logic for consolidating the motion detection signals of the electric fan into one input port There is one in which input ports are reduced using a sum circuit (see, for example, Patent Document 1).

  Further, when a plurality of operation detection signals are input to the OR circuit through one input port and the output from the OR circuit indicates an abnormality, for example, a failure of the electric fan is likely to occur. There is one that is driven in order to identify a fault location (that is, a faulty electric fan) (for example, see Patent Document 2).

JP-A-5-167281 JP 2005-256617 A

  However, as described in Patent Document 2, in the method of driving the drive parts such as the electric fan in the order of high possibility of failure (failure probability) and specifying the failure part, the same part is used at a plurality of places. In some cases, it is difficult to order the failure probability. For this reason, it takes time to identify the failed part.

  Accordingly, an object of the present invention is to provide a faulty drive unit identification device that can easily identify a faulty drive unit in a short time when specifying a faulty component in a plurality of drive units (drive components). It is in.

  In order to achieve the above object, a faulty drive unit identification device according to the present invention includes a plurality of drive units, and is used in a processing device that performs drive control of the drive units to perform predetermined processing. A failure drive unit identification device that receives a logical sum signal obtained by logically summing operation state signals indicating an operation state and identifies a failed drive unit among the plurality of drive units as a failure drive unit, wherein the plurality of drive units are When sequentially driving, a storage unit that stores a table in which the order of driving the plurality of driving units according to the progress stage of the predetermined process is defined as a priority, and a state in which the logical sum signal indicates no abnormality A stage detecting means for detecting a progress stage of the predetermined process when the state changes to an abnormal state, and the plurality of drives when the logical sum signal changes from a state indicating no abnormality to a state indicating abnormality. Part once Stop, refer to the table according to the progress stage detected by the stage detection means from the storage means, control means for sequentially driving the plurality of drive units according to the priority order defined in the table; When the plurality of drive units are sequentially driven and controlled, when the logical sum signal changes from a state indicating no abnormality to a state indicating abnormality, the driving is performed immediately before the logical sum signal is changed from no abnormality to abnormality. And specifying means for specifying the drive unit as a faulty drive unit.

  According to the present invention, when a faulty part is specified in a plurality of drive parts (drive parts), the faulty drive part can be easily specified in a short time.

1 is a cross-sectional view schematically illustrating an example of an image forming apparatus in which a failure drive unit specifying device according to an embodiment of the present invention is used. FIG. 2 is a block diagram illustrating an example of a control unit provided in the image forming apparatus illustrated in FIG. 1. 3 is a time chart for explaining the timing of paper conveyance during single-sided conveyance in the image forming unit shown in FIG. 1. FIG. 3 is a diagram for explaining a configuration of an error detection circuit provided in the I / O interface shown in FIG. 2. 6 is a timing chart for explaining the operation of the CPU when an error is detected in the error detection circuit shown in FIG. 4. It is a flowchart for demonstrating the operation | movement in the case of single-sided conveyance in CPU shown in FIG. It is a flowchart for demonstrating in detail the failure location identification process shown in FIG. FIG. 2 is a diagram showing a prioritization table used when specifying a failure location (failed part) in the image forming apparatus shown in FIG. 1.

  Hereinafter, an example of a failure drive unit identification device according to an embodiment of the present invention will be described with reference to the drawings.

  FIG. 1 is a cross-sectional view schematically showing an example of an image forming apparatus in which a failure drive unit specifying device according to an embodiment of the present invention is used.

  Referring to FIG. 1, an illustrated image forming apparatus 200 is an image forming apparatus using an electrophotographic process. The image forming apparatus 200 includes an image forming unit 180, an image reading unit 176, and a document conveying unit 177.

  The image forming unit 180 is a so-called quadruple tandem type image forming unit having four image forming units 1Y, 1M, 1C, and 1Bk arranged in a line. The yellow image forming unit 1Y forms a yellow image. The magenta image forming unit 1M forms a magenta color image. The cyan image forming unit 1C forms a cyan image. The black image forming unit 1Bk forms a black image.

  In FIG. 1, the intermediate transfer belt 8 is disposed below the image forming units 1Y, 1M, 1C, and 1Bk. The intermediate transfer belt 8 is stretched around the secondary transfer counter roller 10 and the tension roller 11. The secondary transfer roller 12 is disposed in the secondary transfer portion 34 so as to face the secondary transfer counter roller 10 with the intermediate transfer belt 8 interposed therebetween. The intermediate transfer belt 8 is made of a dielectric resin film such as polycarbonate, polyethylene terephthalate resin, or polyvinylidene fluoride resin.

  A paper feeding device 17 (paper feeding unit) is disposed below the image forming unit 180. The sheet feeding device 17 includes a cassette 18, a pickup roller 30, a sheet feeding roller 20, a sheet feeding sensor PS1, and a sheet feeding guide (not shown).

  The recording medium P is stored in the cassette 18, and the recording medium P is sent out from the cassette 18 one by one by the pickup roller 30. The paper feed roller 20 conveys the recording medium P sent out by the pickup roller 30 to the registration roller 19 (registration unit). The registration roller 19 is disposed in front of the image forming unit.

  The registration roller 19 conveys the recording medium P to the secondary transfer unit 34 in synchronization with the image forming timing of the image forming units 1Y, 1M, 1C, and 1Bk based on the detection result of the recording medium P detected by the registration sensor PS2. To do.

  In FIG. 1, a fixing device 16 is disposed on the upper left side of the image forming unit 180. The recording medium P is conveyed to the fixing device 16 along a conveyance path R that passes through the secondary transfer portion 34 and extends in the vertical direction. The fixing device 16 includes a fixing film 16a including a heater 116 formed of a ceramic substrate or the like, and a pressure roller 16b pressed against the heater 116 with the fixing film 16a interposed therebetween.

  A heat source may be provided inside the pressure roller 16b. Further, in the conveyance direction of the recording medium P, a conveyance guide (not shown) for guiding the recording medium P to the fixing nip portion 31 between the fixing film 16a and the pressure roller 16b is provided on the upstream side of the fixing device 16. ing.

  A discharge roller 21 and a paper discharge sensor PS3 are provided downstream of the fixing device 16 in the conveyance direction of the recording medium P. The discharge roller 21 discharges the recording medium P conveyed from the fixing device 16 to a discharge tray 182 provided between the image forming unit 180 and the image reading unit 176.

  Each of the image forming units 1Y, 1M, 1C, and 1Bk includes drum-type electrophotographic photosensitive members (hereinafter referred to as photosensitive drums) 2Y, 2M, 2C, and 2Bk that are used as image carriers. Around the photosensitive drums 2Y, 2M, 2C, and 2Bk, chargers 3Y, 3M, 3C, and 3Bk, developing devices 4Y, 4M, 4C, and 4Bk, primary transfer rollers 5Y, 5M, 5C, and 5Bk, respectively. Cleaning blades 6Y, 6M, 6C, and 6Bk are arranged.

  Each of the developing devices 4Y, 4M, 4C, and 4Bk contains a yellow developer (yellow toner), a magenta developer (magenta toner), a cyan developer (cyan toner), and a black developer (black toner). Has been.

  An exposure device 117 is disposed above the image forming units 1Y, 1M, 1C, and 1Bk. The exposure device 117 is, for example, a laser scanner unit that includes a laser light emitting device, a polygon mirror, an f-θ lens, and a reflection mirror (both not shown).

  The laser light emitting device emits a laser beam modulated according to a time-series digital pixel signal which is image information (image data). The laser beam output from the exposure device 117 exposes the photosensitive drums 2Y, 2M, 2C, and 2Bk between the chargers 3Y, 3M, 3C, and 3Bk and the developing devices 4Y, 4M, 4C, and 4Bk, respectively. To do.

  The photosensitive drums 2Y, 2M, 2C, and 2Bk are, for example, negatively charged organic photoreceptors in which an organic photoconductor (OPC) photosensitive layer is provided on an aluminum drum base. The primary transfer rollers 5Y, 5M, 5C, and 5Bk face the photosensitive drums 2Y, 2M, 2C, and 2Bk through the intermediate transfer belt 8, respectively. The primary transfer rollers 5Y, 5M, 5C, and 5Bk define primary transfer portions 32Y, 32M, 32C, and 32Bk, respectively, between the intermediate transfer belt 8 and the photosensitive drums 2Y, 2M, 2C, and 2Bk.

  Next, an image forming process in which the image forming apparatus 200 forms an image on the recording medium P will be described.

  The photosensitive drums 2Y, 2M, 2C, and 2Bk are driven by a driving device (not shown) in a direction (counterclockwise direction) indicated by a solid line arrow in FIG. Rotates at V1. The image forming speed V1 can be expressed by the rotational speed or surface speed of the photosensitive drums 2Y, 2M, 2C, and 2Bk. Alternatively, the image forming speed V1 can also be expressed by the surface speed of the intermediate transfer belt 8. In synchronization with the rotation of the photosensitive drums 2Y, 2M, 2C, and 2Bk, the intermediate transfer belt 8 rotates in the clockwise direction.

  The chargers 3Y, 3M, 3C, and 3Bk are uniformly charged at predetermined negative potentials on the surfaces of the photosensitive drums 2Y, 2M, 2C, and 2Bk by a charging bias applied from a charging bias power source (not shown). Is charged. The exposure device 117 irradiates the surfaces of the photosensitive drums 2Y, 2M, 2C, and 2Bk uniformly charged by the chargers 3Y, 3M, 3C, and 3Bk with a laser beam that is modulated according to image information. As a result, electrostatic latent images are formed on the surfaces of the photosensitive drums 2Y, 2M, 2C, and 2Bk.

  More specifically, the exposure device 117 performs exposure according to yellow image information in the yellow image forming unit 1Y, and forms a yellow electrostatic latent image on the photosensitive drum 2Y. A voltage having the same polarity and the same potential as the charging polarity of the photosensitive drum 2Y is applied to a developing roller (not shown) provided in the yellow developing device 4Y. The developing device 4Y develops the electrostatic latent image on the photosensitive drum 2Y with yellow toner, and visualizes it as a yellow toner image.

  Next, a voltage having a polarity opposite to that of the toner is applied to the primary transfer roller 5Y. As a result, the yellow toner image on the photosensitive drum 2Y is primarily transferred onto the intermediate transfer belt 8 in the primary transfer portion 32Y.

  Similarly, electrostatic latent images are formed on the photosensitive drums 2M, 2C, and 2Bk in the magenta image forming unit 1M, the cyan image forming unit 1C, and the black image forming unit 1Bk. These electrostatic latent images are developed by magenta, cyan, and black developing devices 4M, 4C, and 4Bk, respectively. As a result, a magenta toner image, a cyan toner image, and a black toner image are formed on the photoreceptors 2M, 2C, and 2Bk, respectively.

  The magenta toner image, cyan toner image, and black toner image are sequentially transferred and superimposed on the intermediate transfer belt 8 at the primary transfer portions 32M, 32C, and 32Bk by the primary transfer rollers 5M, 5C, and 5Bk, respectively. Then, a color toner image is formed on the intermediate transfer belt 8. At this time, the secondary transfer roller 12 is not in contact with the intermediate transfer belt 8.

  The cleaning blades 6Y, 6M, 6C, and 6Bk scrape the transfer residual toner remaining on the photosensitive drums 2Y, 2M, 2C, and 2Bk after the primary transfer, respectively, so that the photosensitive drums 2Y, 2M, 2C, and Clean the 2Bk surface.

  The secondary transfer roller 12 contacts the intermediate transfer belt 8 to form a secondary transfer portion 34. The color toner image on the intermediate transfer belt 8 is secondarily transferred to the recording medium P conveyed from the paper feeding device 17 in the secondary transfer unit 34. The recording medium P is conveyed to the fixing device 16. The color toner image transferred onto the recording medium P is fixed on the recording medium P by the fixing device 16 to become a color image. The recording medium P on which the color image is formed is discharged to the discharge tray 182 by the discharge roller 21.

  FIG. 2 is a block diagram illustrating an example of a control unit provided in the image forming unit 180 illustrated in FIG.

  Referring to FIG. 2, in image forming apparatus 200, image forming unit 180 includes image forming control unit 100 and image processing control unit 150. The image forming control unit 100 includes chargers 3Y, 3M, 3C, and 3Bk, an exposure device 117, developing devices 4Y, 4M, 4C, and 4Bk, primary transfer rollers 5Y, 5M, 5C, and 5Bk, a paper feeding device 17, and The fixing device 16 is controlled.

  The image formation control unit 100 includes a CPU 101 and a motor driver board (not shown), and the CPU 101 controls image formation by the image formation unit 180. A read-only memory (ROM) 103 stores a program (image formation control program) for controlling the apparatus main body 201 (FIG. 1). The CPU 101 sequentially reads the program from the ROM 103 and executes the read program.

  The CPU 101 is connected to the ROM 103, RAM 104, input / output (I / O) interface 106, nonvolatile RAM 120, and scanner control circuit 121 by an address bus and a data bus. A random access memory (RAM) 104 used as a main storage device is used as a storage area for input data and a storage area for work. The nonvolatile RAM 120 is used as a storage area for parameters related to the image forming operation.

  The I / O interface 106 is connected to motors 107, clutches 108, and solenoids 109 for driving the paper feed system, the transport system, and the optical system, and is a paper detection sensor for detecting the recording medium P. And a fan (FAN) 115 for cooling the image forming unit 180.

  The developing devices 4Y, 4M, 4C, and 4Bk are provided with a remaining toner detector (toner sensor) 111 that detects the amount of toner in the developing devices 4Y, 4M, 4C, and 4Bk, respectively. The toner remaining amount detector 111 is connected to the I / O interface 106, and an output signal of the toner remaining amount detector 111 is input to the I / O interface 106.

  The switches 112 are used to detect home positions of loads such as the motors 107, the clutches 108, the solenoids 109, the paper detection sensors 110, and the toner sensor 111. Output signals from the switches 112 are input to the I / O interface 106. The high voltage power supply 113 is connected to the I / O interface 106. The high voltage power supply 113 supplies high voltage to the chargers 3Y, 3M, 3C, and 3Bk, the developing devices 4Y, 4M, 4C, and 4Bk, and the transfer rollers 5Y, 5M, 5C, and 5Bk according to instructions from the CPU 101 To do. A heater 116 provided in the fixing device 16 is connected to the I / O interface 106. An AC voltage is supplied to the heater 116 in response to an on / off signal.

  The image processing control unit 150 performs image processing on an image signal from an externally connected device such as a personal computer (hereinafter referred to as a PC) or the reading processing unit 170 to generate image information (image data). Further, the image processing control unit 150 stores image information obtained by performing image processing on the image signal transmitted from the reading processing unit 170 in a storage medium such as a USB memory connected to an externally connected device such as a PC or the operation unit 181. can do.

  The ROM 153 stores a program (image processing control program) for controlling image processing by the image processing control unit 150. The CPU 151 provided in the image processing control unit 150 sequentially reads the program from the ROM 153 and executes the program. The RAM 154 used as the main storage device is used as a storage area for input data, a working storage area, and the like.

  In the image processing control unit 150, the recording processing circuit 157 performs image processing on an image signal sent from the reading processing unit 170 or an externally connected device such as a PC, and performs pulse width modulation on the laser light emitted from the exposure device 117. Image information (PWM data) is generated. The recording processing circuit 157 controls the exposure device (laser unit) 117 to cause the exposure device 117 to emit laser light that has been subjected to pulse width modulation according to image information. The pulse width-modulated laser light is applied to the photosensitive drums 2Y, 2M, 2C, and 2Bk, and forms an electrostatic latent image on the photosensitive drums 2Y, 2M, 2C, and 2Bk as described above. .

  The laser light is detected by a beam detection sensor (BD sensor) 114 provided in the non-image areas of the photosensitive drums 2Y, 2M, 2C, and 2Bk. The BD sensor 114 outputs a BD signal (synchronization signal in the main scanning direction) that synchronizes the writing of the image signal in each scan.

  This BD signal is input to the scanner control circuit 121. The scanner control circuit 121 controls the rotation of a polygon motor (not shown) provided in the exposure apparatus 117 according to the BD signal. In addition, the scanner control circuit 121 outputs an image synchronization signal to the image processing control unit 150.

  The nonvolatile RAM 161 is used as a storage area for parameters related to image processing. The I / O interface 156 is connected to motors 173, solenoids 174, and sensors 175 provided in the reading processing unit 170. The reading processing circuit 160 drives the reading sensor 172 provided in the image reading unit 176 via the reading control circuit 171 to process the image data obtained from the reading sensor 172.

  The image processing RAM 159 is used as a storage area for temporarily storing data when image processing is performed on data received by the reading processing circuit 160 or data obtained from an externally connected device such as a PC. The LAN control unit 158 is for controlling communication with an external connection device such as a PC connected via a LAN cable.

  The ROM 153, RAM 154, I / O interface 156, recording processing circuit 157, image processing RAM 159, reading processing circuit 160, and nonvolatile RAM 161 are controlled by the CPU 151. The CPU 151 also controls the operation unit 181 which is a user interface for the user to operate the image forming apparatus 200 and the network control unit (NCU) 185 of the facsimile apparatus.

  The CPU 101 of the image forming control unit 100 and the CPU 151 of the image processing control unit 150 are connected by serial communication (serial) of start-stop or clock synchronization. By performing serial communication, control of output timing of image data to the engine unit of the image forming apparatus 200, activation and termination of the image forming apparatus 200, and transition control to a sleep mode are performed.

  FIG. 3 is a time chart for explaining the timing of paper conveyance during single-sided conveyance in the image forming unit 180 shown in FIG.

  1 to 3, the pickup roller 30 is driven to rotate when the paper feed clutch CL1 is turned on (T31). Then, the pickup roller 31 sends out the recording media P from the cassette 18 one by one. The feed roller 20 conveys the recording medium P sent out by the pickup roller 30 to the registration roller 19 as described above. At this time, the paper feed sensor PS1 disposed between the paper feed roller 20 and the registration roller 19 detects the recording medium P and is turned on (T32).

  The registration roller 19 is driven to rotate when the registration clutch CL2 is turned on (T33). The registration roller 19 is driven until the recording medium P is detected by the registration sensor PS2 and the registration sensor PS2 is turned on. When the registration sensor PS2 is turned on (T34), the sheet supply clutch CL1 and the registration clutch CL2 are temporarily turned off (T35) in order to wait for the image formation timing in the image forming units 1Y, 1M, 1C, and 1Bk. To stop.

  When the image forming timings of the image forming units 1Y, 1M, 1C, and 1Bk are reached, the sheet feeding clutch CL1 and the registration clutch CL2 are turned on again (T36), and the recording medium P is conveyed to the secondary transfer unit 34.

  Thereafter, as described above, the toner image on the recording medium P is fixed on the recording medium P by the fixing device 16. When the trailing edge of the recording medium P passes through the paper feed sensor PS1 (T37), the paper feed clutch CL1 is turned off (T38). The recording medium P is conveyed via the discharge roller 21 and turns on the paper discharge sensor PS3 (T39). When the recording medium P passes through the registration sensor PS2 (T40), the registration clutch CL2 is turned off (T41). Thereafter, the paper discharge sensor PS3 is turned off (T42), and the recording medium P is discharged to the discharge tray 182 after being conveyed for a predetermined time.

  FIG. 4 is a diagram for explaining the configuration of the error detection circuit provided in the I / O interface 106 shown in FIG.

  In FIG. 4, the drive circuit CL1 performs on / off control of the paper feed clutch CL1 in the clutches 108, and the drive circuit CL2 performs on / off control of the registration clutch CL2. Driving circuit fans (FAN) 1 to 4 perform on / off control of four FANs of the FANs 115.

  The error detection circuit 1 detects an overcurrent in the paper feed clutch CL1, and turns on the transistor Tr1 when an overcurrent occurs (the collector is set to a low level when the transistor Tr1 is turned on. This low level is an on signal. ). As a result, the input port PI1 of the CPU 101 becomes a low level (Low). Similarly, the error detection circuit 2 detects an overcurrent of the registration clutch CL2, and turns on the transistor Tr2 when an overcurrent occurs. The input port PI1 of the CPU 101 becomes Low.

  The error detection circuits 3 to 6 detect FAN rotation abnormality signals, respectively. That is, the error detection circuits 3 to 6 each output an operation state signal (error signal) indicating the operation state of the FAN. For example, after the driving circuit FAN1 turns on the FAN, when the FAN rotation abnormality occurs, the error detection circuit 3 outputs a rotation abnormality signal. The transistor Tr3 is turned on by this rotation abnormality signal. Then, the input port PI1 of the CPU 101 becomes Low.

  Similarly, when the FAN rotation abnormality occurs after each of the drive circuits FAN2 to FAN4 turns on the FAN, the error detection circuits 4 to 6 turn on the transistors Tr4 to Tr6, respectively. As a result, the input port PI1 of the CPU 101 becomes Low. In this manner, when any of the transistors Tr1 to Tr6 is turned on, a logical sum signal indicating Low is given to the input port PI1 of the CPU 101.

  FIG. 5 is a timing chart for explaining the operation of the CPU 101 when an error is detected in the error detection circuit shown in FIG.

  Referring to FIGS. 4 and 5, when operation of image forming unit 180 starts, CPU 101 turns on output ports FAN1 to FAN4 and controls driving circuits FAN1 to FAN4 (T51). Thereafter, the CPU 101 turns on the output port CL1 to drive and control the drive circuit CL1. As a result, the paper feed clutch CL1 is turned on (T52).

  The recording medium P is conveyed to the registration roller 19 by turning on the paper supply clutch CL1. As a result, the paper feed sensor PS1 is turned on (T53).

  Subsequently, the CPU 101 turns on the output port CL2 to drive and control the drive circuit CL2. As a result, the registration clutch CL2 is turned on, and the registration roller 19 is driven to rotate (T54). Then, the recording medium P is conveyed until the registration sensor PS2 is turned on (T55).

  At this time, when the input port PI1 of the CPU 101 becomes Low by the error detection signal (T56), the CPU 101 detects the occurrence of the error and immediately stops the operation of the image forming unit 180 (T57).

  Subsequently, the CPU 101 confirms the states of the paper feed sensor PS1, the registration sensor PS2, and the paper discharge sensor PS3, predicts an error occurrence location, and specifies an error occurrence location as described later. Prioritize.

  In the illustrated example, the registration clutch CL2 is set to the priority “1” from the state in which the paper feed sensor PS1 and the registration sensor PS2 are on and the paper discharge sensor PS3 is off, and then the paper feeding CL1 and FAN1 to FAN1 are sequentially given priority. To do.

  In accordance with the priority order, the CPU 101 sequentially turns on from the registration clutch CL2, and confirms whether or not the input port PI1 has changed to Low (every time it is turned on) (T58). As a result, the CPU 101 shortens the time (specific time) required for specifying the fault location.

  FIG. 6 is a flowchart for explaining the operation at the time of single-sided conveyance in CPU 101 shown in FIG.

  Referring to FIGS. 4 and 6, when image formation is started, CPU 101 drives (turns on) FAN as described above (first progress stage: step S601). Then, the CPU 101 confirms the state of the input port PI1 and determines whether an error has occurred (step S602). Note that each time the CPU 101 turns on a driving component such as FAN, the CPU 101 holds information indicating the turned-on driving component in the RAM 104.

  If no error occurs (NO in step S602), CPU 101 turns on sheet feeding clutch CL1 (second progress stage: step S603). Then, the COU 101 confirms the state of the input port PI1 and determines whether an error has occurred (step S604).

  If no error occurs (NO in step S604), CPU 101 turns on registration clutch CL2 (third progress stage: step S605). Then, the CPU 101 confirms the state of the input port PI1 and determines whether an error has occurred (step S606).

  If no error occurs (NO in step S606), the CPU 101 turns on the registration sensor (step S607), and then turns off the paper feed clutch CL1 and the registration clutch CL2 (step S608).

  Subsequently, the CPU 101 determines whether image preparation is completed (step S609). That is, the CPU 101 determines whether the image preparation of the image forming units 1Y, 1M, 1C, and 1Bk is completed. If the image preparation is not completed (NO in step S609), the CPU 101 stands by.

  When the image preparation is completed (YES in step S609), the CPU 101 turns on the paper feed clutch CL1 and the registration clutch CL2 (step S610). Thereby, the conveyance of the recording medium P to the discharge tray 182 is started. At this time, the CPU 101 checks the state of the input port PI1 and determines whether an error has occurred (step S611). If no error occurs (NO in step S611), the recording medium P is conveyed to the discharge tray 182 and the CPU 101 confirms whether or not the recording medium P has been discharged (fourth progress stage: step S612). ).

  If the discharge of the recording medium P is not completed (NO in step S612), the CPU 101 stands by. On the other hand, when the discharge of the recording medium P is completed (YES in step S612), the CPU 101 stops (turns off) the driving of the FAN (step S613) and ends the image formation.

  If an error occurs in any of step S602, step S604, step S606, and step S611, that is, if the input port PI1 becomes low, the CPU 101 temporarily stops the operation of the image forming unit 180 (step S614). Then, the CPU 101 performs a failure location specifying process, which will be described later, and specifies the failure location (step S615).

  FIG. 7 is a flowchart for explaining in detail the failure location specifying process shown in FIG.

  Referring to FIGS. 4 and 7, when the failure location specifying process is started, first, CPU 101 picks up driving components (FAN, clutch, and sensor) that were turned on when an error occurred from RAM 104 (step S701). ). Next, the CPU 101 monitors the sensor output of the image forming unit 180 that has stopped operating, the temperature of the image forming unit 180, and the like (step S702). Although not shown in FIG. 4, a temperature sensor (temperature detection means) is connected to the CPU 101.

  Then, in accordance with the monitoring, the CPU 101 detects the state of the device such as the identification of the current position of the recording medium P of the image forming unit 180 and the state of the driving component such as the detection of the position of the gear, and the priority order for re-driving the driving component. Is determined (step S703).

  FIG. 8 is a diagram showing a prioritization table used when specifying a failure location (failed part) in the image forming apparatus shown in FIG.

  The prioritization table shown in FIG. 8 is stored in the nonvolatile RAM 120, for example. In this prioritization table, conditions 1 to 5 are defined, and the on / off states of the paper feed sensor PS1, the registration sensor PS2, and the paper ejection sensor PS3 are defined corresponding to the conditions 1 to 5. ing. Further, the temperature (in-machine temperature) of the image forming unit 180 is defined corresponding to the conditions 1 to 5, and the priorities of the FAN1 to FAN4 and the clutches CL1 and CL2 are defined according to the conditions 1 to 5.

  When the CPU 101 determines that the paper feed sensor PS1, the registration sensor PS2, and the paper discharge sensor PS3 are off and the internal temperature is high (above a predetermined temperature) when an error occurs, the CPU 101 refers to the prioritization table. Assume that Condition 1 is satisfied. Then, after turning on FAN1 to FAN4, the CPU 101 subsequently performs an on process in the order of the paper feed clutch CL1 and the registration clutch CL2 to identify a faulty part.

  If the CPU 101 determines that the paper feed sensor PS1, the registration sensor PS2, and the paper discharge sensor PS3 are off and the internal temperature is the normal temperature (below a predetermined temperature) when an error occurs, the CPU 101 refers to the prioritization table. Assume that condition 2 is satisfied. Then, the CPU 101 performs the ON process in the order of the paper feed clutch CL1, FAN1 to 4, and the registration clutch CL2 to identify the failed part.

  When an error occurs, the CPU 101 determines that the paper feed sensor PS1 is on, the registration sensor PS2 and the paper discharge sensor PS3 are off, and the in-machine temperature is the normal temperature. 3 is satisfied. Then, the CPU 101 performs an ON process in the order of the registration clutch CL2, the paper feed clutch CL1, and the FAN1 to FAN1 to identify the failed part.

  When the CPU 101 determines that the paper feed sensor PS1 and the registration sensor PS2 are on and the paper discharge sensor PS3 is off and the in-machine temperature is the normal temperature when an error occurs, the CPU 101 refers to the prioritization table to determine the condition. 4 is satisfied. Then, the CPU 101 performs an ON process in the order of the registration clutch CL2, the paper feed clutch CL1, and the FAN1 to FAN1 to identify the failed part.

  When an error occurs, the CPU 101 refers to the prioritization table when it determines that the paper feed sensor PS1 is off, the registration sensor PS2 is on, and the paper discharge sensor PS3 is off and the internal temperature is the normal temperature. Assume that Condition 5 is satisfied. Then, the CPU 101 performs an ON process in the order of the registration clutch CL2, FAN1 to 4, and the paper feed clutch CL1 to identify the failed part.

  As described above, the CPU 101 sequentially controls (turns on) the drive components in the order defined in the prioritization table (step S704), and detects whether an error occurs (step S705). If no error occurs (NO in step S705), the CPU 101 returns to the process of step S704 and turns on the next drive component.

  On the other hand, if an error occurs (YES in step S705), the CPU 101 determines that the drive component (drive unit) that was turned on (driven) immediately before the error has occurred, that is, the failure location ( Identify the faulty part). Then, the CPU 101 ends the failure location identification. In the table with priority shown in FIG. 8, the in-machine temperature is associated, but the in-machine temperature need not be used.

  In this way, when an error occurs, the CPU 101 repeats steps S704 and S704 until a faulty part is specified to specify the faulty part.

  Referring to FIGS. 4 and 6 again, after identifying the failure location as described above, CPU 101 notifies CPU 151 of component information indicating the failed component by serial communication (error notification: step S618). Then, the CPU 101 ends the image formation.

  As described above, in the image forming apparatus according to the embodiment of the present invention, when detecting the failure of a plurality of driving components, the abnormality detection signals obtained from the respective driving components are logically summed and one input port of the CPU 101. However, the drive order for identifying the failed part is determined according to the state of the image forming apparatus when an abnormality (error) occurs, so that the failed part can be identified in a shorter time. Can do.

  As is apparent from the above description, in FIG. 5, the CPU 101, the paper feed sensor PS1, the registration sensor PS2, and the paper discharge sensor PS3 function as a stage detection unit. The CPU 101 functions as a control unit and a specifying unit. Each of the paper feed sensor PS1, the registration sensor PS2, and the paper discharge sensor PS3 is a detection sensor, and detects a progress stage during image formation.

  As mentioned above, although this invention was demonstrated based on embodiment, this invention is not limited to these embodiment, Various forms of the range which does not deviate from the summary of this invention are also contained in this invention. .

100 Image formation control unit 101, 151 CPU
106, 156 I / O section 107 Motors 108 Clutches 109 Solenoids 110 Paper detection sensors 111 Toner sensor 112 Switches 115 FANs

Claims (6)

A plurality of drive units, and used in a processing device that performs drive control of the drive units to perform predetermined processing, and receives an OR signal obtained by ORing operation state signals indicating operation states of the plurality of drive units; A failure drive unit identification device that identifies a failed drive unit among a plurality of drive units as a failure drive unit,
Storage means for storing a table in which the order of driving the plurality of drive units is defined as a priority in accordance with the progress stage of the predetermined process when sequentially driving the plurality of drive units;
Stage detecting means for detecting a progress stage of the predetermined process when the logical sum signal changes from a state indicating no abnormality to a state indicating abnormality;
When the logical sum signal changes from a state indicating no abnormality to a state indicating abnormality, the plurality of driving units are temporarily stopped, and the table corresponding to the progress stage detected by the stage detection unit is stored in the table. A control unit that refers to the unit and sequentially drives and controls the plurality of driving units according to the priority order defined in the table;
When the plurality of drive units are sequentially driven and controlled, when the logical sum signal changes from a state indicating no abnormality to a state indicating abnormality, the driving is performed immediately before the logical sum signal is changed from no abnormality to abnormality. A fault drive unit specifying apparatus comprising: a specifying unit that specifies a drive unit as a fault drive unit. The table defines the priority in association with the temperature of the processing apparatus,
Having temperature detection means for detecting the temperature of the processing apparatus;
In addition to the progress stage detected by the stage detection means, the control means refers to the table according to the temperature detected by the temperature detection means, and the plurality of drives according to the priority order defined in the table. The failure drive unit identification device according to claim 1, wherein the drive units are sequentially driven and controlled.   The fault drive unit identification device according to claim 1, wherein the processing device is an image processing device that forms an image on a recording medium in accordance with image data.   In the proceeding step, at least a first proceeding step of turning on a fan provided in the image forming apparatus, a second proceeding step of feeding the recording medium from a sheet feeding unit accommodated from the recording medium, and the recording And a third progress stage for driving a resist portion positioned in front of the image forming section for forming an image on the medium, and a fourth progress stage for discharging the recording medium on which the image has been formed. The fault drive part specifying device according to claim 3.   The fault drive unit identification device according to claim 4, further comprising a detection sensor for detecting the second progress stage, the third progress stage, and the fourth progress stage. Error detection means for detecting whether an error has occurred in each of the plurality of drive units and outputting an error detection signal; and
Switch means having a plurality of switches respectively associated with the plurality of driving units,
The switch is turned on when receiving the error signal, and the switch means outputs an ON signal indicating that any one of the switches is turned on as the logical sum signal. The fault drive part specifying device according to any one of the above.

Images