JP2005065380A - Image forming apparatus and management system thereof - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an image forming apparatus management system which can predict the lifetime of a mechanical drive system in advance from a variation by replacing a load fluctuation resulting from aging, etc. to variation of current step-out of a stepping motor. <P>SOLUTION: The image forming apparatus management system includes at least one image forming apparatus, and a host device for managing the image forming apparatus via a network. The image forming apparatus management system includes the stepping motor for driving a drive system in the image forming apparatus, a drive control means for driving the stepping motor, a current control means for changing output current of the stepping motor, and a step-out detecting means for detecting the step-out of the stepping motor by changing the output current of the stepping motor by the current control means. The lifetime of the drive system is predicted from a current value when the step-out of the stepping motor is detected by the step-out detecting means. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a technique for predicting the lifetime of a mechanical drive system that is driven using a stepping motor in an image forming apparatus.

  Conventionally, when a load of a mechanical drive system or the like in an image forming apparatus such as a copying machine is performed by a DC (direct current) motor, a current flowing through the motor is monitored with respect to an increase of the drive system load caused by a change with time. Then, when the monitored current value exceeds a certain fixed value, it is predicted that the drive system will be broken, and this is notified to an external device (see, for example, Patent Document 1).

JP 05-265273 A

  However, in recent years, the use of a stepping motor is increasing because the method of using a motor for driving a load is simple and allows high-precision control driving. There are constant voltage and constant current controls in this stepping motor control, but the maximum current that flows is defined by the winding resistance in the motor. It is not possible in principle to monitor the change of. Therefore, it is necessary to monitor load fluctuations using a new method.

  The present invention solves the above-mentioned problems, and its purpose is to replace the load fluctuation caused by a change with time etc. with a change in current that the stepping motor steps out and predict the life of the mechanical drive system in advance from the change. It is an object of the present invention to provide an image forming apparatus and an image forming apparatus management system that can be used.

  In order to achieve the above object, the invention according to claim 1 is an image forming apparatus management system comprising at least one image forming apparatus and a host device that manages the image forming apparatus via a network. A stepping motor for driving the drive system, drive control means for driving the stepping motor, current control means for changing the output current of the stepping motor, and changing the output current of the stepping motor by the current control means. A step-out detecting means for detecting step-out of the stepping motor, and predicting the life of the drive system from the current value when the step-out detecting means detects the step-out of the stepping motor. And

  According to a second aspect of the present invention, in the first aspect of the invention, there is provided storage means for storing a current value when a step-out is detected, and the drive system is based on the current value stored in the storage means. It is characterized by predicting the lifetime.

  According to a third aspect of the present invention, in the first or second aspect of the present invention, the detection by the step-out detection unit is performed during an initial operation of the image forming apparatus or at a predetermined interval.

  According to a fourth aspect of the present invention, in the first or second aspect of the present invention, the display unit further includes a display unit, and the display unit displays a warning result of a predicted life of the drive system.

  According to a fifth aspect of the present invention, there is provided a stepping motor for driving a drive system in the apparatus, drive control means for driving the stepping motor, current control means for changing an output current of the stepping motor, and the current control means. A step-out detecting means for detecting a step-out of the stepping motor by changing an output current of the stepping motor, and the driving from the current value when the step-out detecting means detects the step-out of the stepping motor. It is characterized by predicting the lifetime of the system.

  According to a sixth aspect of the present invention, in the fifth aspect of the present invention, the storage unit stores a current value when a step-out is detected, and the drive system is configured based on the current value stored in the storage unit. It is characterized by predicting the lifetime.

  The invention described in claim 7 is the invention described in claim 5 or 6, characterized in that the detection by the step-out detection means is performed during an initial operation of the image forming apparatus or at a predetermined interval.

  The invention according to claim 8 is the invention according to claim 5 or 6, further comprising a display unit, wherein the display unit displays a warning result of a predicted life of the drive system.

  According to the present invention, it is possible to predict in advance the life of a mechanical drive system that is driven and controlled using a stepping motor.

  Embodiments of the present invention will be described below with reference to the drawings.

  FIG. 1 is a vertical cross-sectional view showing a main part configuration of the image forming apparatus. As shown in FIG. 1, the image forming apparatus includes an image forming apparatus main body 10, a folding apparatus 400, and a finisher 500. The image forming apparatus main body 10 includes an image reader 200 and a printer 300 that read a document image.

  A document feeder 100 is mounted on the image reader 200. The document feeder 100 feeds documents set upward on the document tray one by one to the left sequentially from the first page, conveys them onto the platen glass 102 through a curved path, and stops at a predetermined position. In this state, when the scanner unit 104 is scanned from left to right, the reading surface of the document is irradiated with the light from the lamp 103 of the scanner unit 104, and the reflected light from the document passes through the mirrors 105, 106, and 107. Guided to the lens 108. The light that has passed through the lens 108 forms an image on the imaging surface of the image sensor 109.

  The read original is discharged toward an external paper discharge tray 112. By driving the scanner unit 104 so as to pass through the reading position from left to right in this way, a document whose main scanning direction is the direction orthogonal to the driving direction of the scanner unit 104 and whose driving direction is the sub-scanning direction. A read scan is performed. That is, when the scanner unit 104 passes the reading position, the entire original image is read by driving the scanner unit 104 in the sub-scanning direction while reading the original image by the image sensor 109 line by line in the main scanning direction. The optically read image is converted into image data by the image sensor 109 and output.

  Image data output from the image sensor 109 is input as a video signal to the exposure control unit 110 of the printer 300 after predetermined processing is performed in an image signal control unit 202 described later. A document is fed from the left on the platen glass 102 by the document feeder 100 and conveyed to the right after passing through the reading position. Thereafter, the document is discharged toward an external discharge tray 112. When the original passes through the sink reading position on the platen glass 102 from left to right, the original image is read by the scanner unit 104 held at a position corresponding to the sink reading position. This reading method is generally referred to as document scanning.

  When reading a document without using the document feeder 100, first, the user lifts the document feeder 100 to place the document on the platen glass 102, and then scans the scanner unit 104 from left to right. The original is read by. That is, when reading a document without using the document feeder 100, a fixed document reading is performed.

  The exposure control unit 110 of the printer 300 modulates and outputs a laser beam based on the input video signal, and the laser beam is irradiated onto the photosensitive drum 111 while being scanned by the polygon mirror 110a. An electrostatic latent image corresponding to the scanned laser beam is formed on the photosensitive drum 111. Here, as will be described later, the exposure control unit 110 outputs a laser beam so that a correct image (an image that is not a mirror image) is formed during fixed document reading.

  The electrostatic latent image on the photosensitive drum 111 is visualized as a developer image by the developer supplied from the developing device 113. In addition, at the timing synchronized with the start of laser light irradiation, paper is fed from each of the cassettes 114 and 115, the manual paper feeding unit 125 or the double-sided conveyance path 124, and this paper is placed between the photosensitive drum 111 and the transfer unit 116. It is conveyed to. The developer image formed on the photosensitive drum 111 is transferred onto a sheet fed by the transfer unit 116.

  The sheet on which the developer image is transferred is conveyed to the fixing unit 117, and the fixing unit 117 fixes the developer image on the sheet by heat-pressing the sheet. The sheet that has passed through the fixing unit 117 is discharged from the printer 300 toward the outside (folding device 400) through the flapper 121 and the discharge roller 118.

  Here, when the sheet is discharged with its image forming surface facing downward (face-down), the sheet that has passed through the fixing unit 117 is once guided into the reverse path 122 by the switching operation of the flapper 121, and the trailing edge of the sheet. After passing through the flapper 121, the paper is switched back and discharged from the printer 300 by the discharge roller 118. Hereinafter, this form of paper discharge is referred to as reverse paper discharge. This reverse paper discharge is performed when images are formed in order from the first page, such as when an image read using the document feeder 100 is formed or when an image output from a computer is formed. The paper order after paper discharge is the correct page order.

  In addition, when a hard sheet such as an OHP sheet is fed from the manual sheet feeding unit 125 and an image is formed on the sheet, the image forming surface is faced up without leading the sheet to the reverse path 122 (face-up). ) By the discharge roller 118.

  Further, when double-sided recording for image formation is set on both sides of the paper, the paper is guided to the reverse path 122 by the switching operation of the flapper 121 and then transported to the double-sided transport path 124 and then guided to the double-sided transport path 124. Control is performed so that the fed paper is fed again between the photosensitive drum 111 and the transfer unit 116 at the timing described above.

  The paper discharged from the printer 300 is sent to the folding device 400. The folding device 400 performs a process of folding a sheet into a Z shape. For example, when an A3 size sheet or B4 size sheet is specified and the folding process is specified, the folding apparatus 400 performs the folding process. In other cases, the paper discharged from the printer 300 passes through the folding apparatus 400. It is sent to the finisher 500. The finisher 500 is provided with an inserter 900 for feeding a special sheet such as a cover sheet or a slip sheet to be inserted into a sheet on which an image is formed. The finisher 500 performs bookbinding processing, binding processing, punching, and other processing.

  Next, the configuration of a controller that controls the entire image forming apparatus will be described with reference to FIG. FIG. 2 is a block diagram showing the configuration of a controller that controls the entire image forming apparatus shown in FIG.

  As shown in FIG. 2, the controller includes a CPU circuit unit 150. The CPU circuit unit 150 includes a CPU (not shown), a ROM 151, a RAM 152, and an HDD 154, and is controlled by a control program stored in the ROM 151. Blocks 101, 153, 201, 202, 301, 401, and 501 are collectively controlled. The RAM 152 temporarily stores control data and is used as a work area for arithmetic processing associated with control. The HDD 154 is used to temporarily store image data when an original is read, and to store adjustment values of each part of the image forming apparatus.

  The document feeder control unit 101 controls driving of the document feeder 100 based on an instruction from the CPU circuit unit 150. The image reader control unit 201 performs drive control on the above-described scanner unit 104, the image sensor 109, and the like, and transfers an analog image signal output from the image sensor 109 to the image signal control unit 202.

  The image signal control unit 202 converts each analog image signal from the image sensor 109 into a digital signal, performs each process, converts the digital signal into a video signal, and outputs the video signal to the printer control unit 301. The processing operation by the image signal control unit 202 is controlled by the CPU circuit unit 150. The printer control unit 301 drives the above-described exposure control unit 110 based on the input video signal.

  The operation unit 153 includes a plurality of keys for setting various functions relating to image formation, a display unit for displaying information indicating a setting state, and the like, and outputs a key signal corresponding to the operation of each key to the CPU circuit unit 150. At the same time, the corresponding information is displayed on the display unit based on the signal from the CPU circuit unit 150.

  The folding device control unit 401 is mounted on the folding device 400 and performs drive control of the entire folding device by exchanging information with the CPU circuit unit 150.

  The finisher control unit 501 is mounted on the finisher 500 and performs drive control of the entire finisher by exchanging information with the CPU circuit unit 150.

  The communication control unit 1001 controls the exchange of information with the outside using a network or the like.

  Subsequently, a network device management apparatus according to an embodiment of the present invention will be described with reference to the accompanying drawings.

<Remote management system configuration via network>
FIG. 8 is a block diagram of a remote management system using a network. FIG. 3 is a diagram illustrating a case where a network board (NEB) [A-030] for connecting an image forming apparatus and a printer to a network is connected to a printer [A-031] having an open architecture.

  The NEB [A-030] is connected to the local area network [LAN] [A-000] via a LAN interface such as an Ethernet interface 10Base-2 having a coaxial connector or a 10Base-T having a RJ-45, or a 100Base-T. It is connected.

  A plurality of personal computers (PC) such as PC [A-011] are also connected to the LAN (A-000), and under the control of the network operating system, PC [A-011] is NEB [A-030]. ] Can be communicated. In this state, one of the PCs can be designated as the network management unit.

  Further, a device management PC [A-300] for performing the present system is connected to the LAN [A-000]. Furthermore, a database management server (not shown) that manages the database of the device management PC is connected. The database management server may be included in the device management server [A-300]. The device management PC collects device data by using a predetermined data format and a predetermined protocol.

  A-001 is the Internet that connects a plurality of LANs, and [A-800] is a host device that collects data from a device management PC connected to each LAN.

<Device management protocol on the network>
As a method for managing devices on a network, several attempts have been made by many standard organizations. The International Organization for Standardization (ISO) provided a general reference framework called the Open System Interconnect (OSI) model. The OSI model of the network management protocol is called a common management information protocol (CMIP). CMIP is a European common network management protocol.

  In the United States, there is a CMIP protocol called Simple Network Management Protocol (SNMP) as a more common network management protocol.

  According to this SNMP network management technology, a network management system includes at least one network management station, several managed nodes each including an agent, and network management used by the management station and the agent to exchange management information. Includes protocol.

  In addition, the agent holds data regarding its own state in the form of a database. This database is called MIB (Management Information Base).

  The MIB has a tree-structured data structure and is defined by RFC1155 Structure and Identification of Management Information TCP / IP-based Internets.

  In this MIB, there is a node called a private MIB, and a company or organization can define its own MIB.

<Device management device>
FIG. 9 is a configuration diagram of the device management apparatus A-300.

  A-301 is a CPU that controls the whole, A-302 is a RAM that is a working area necessary for the CPU to operate, and A-303 is a HardDisk (A-303) that stores a program instructing the operation of the CPU. A-304 is a database for storing various copy counter values, status information such as jams, errors, alarm information, component counters, and MIB information (A-303 and A304 are the same HardDisk). A-305 is a display for the user to browse the device management UI, A-306 is a serial interface for communicating with a modem, and A-307 is an interface for communicating with a network (LAN). is there.

  Hereinafter, the operation of the device management apparatus will be described with reference to the drawings. FIG. 10 is a flowchart showing the operation (processing) of the device management apparatus.

  The device management apparatus is normally in an idle state (A-402). When waiting for an event from the image forming apparatus and receiving the event (A-403), the image forming apparatus is requested for data corresponding to the event (for example, jam data if a jam event) (A-407). . The image forming apparatus sends data in response to a data request from the device management apparatus. When acquiring data from the image forming apparatus, the device management apparatus accumulates the data in the database.

  If there is data such as error data that needs to be urgently notified to the host, it is immediately sent to the host (A-408).

  Similarly, the device management apparatus waits for an event from the host (A-405), and when there is a request for a counter value or a component counter (A-406), data corresponding to the request from the management database of the device management apparatus. Is sent to the host (A-409).

  Further, the device management apparatus performs periodic monitoring of the device. When a predetermined time is reached (A-404), the device management apparatus collects various counter values of the monitored device (A-405). Data collected by the device management apparatus is stored in a predetermined format (not shown) in the database.

<Data communication sequence between device management device and host device>
There are three methods for data transmission / reception between the device management apparatus and the host apparatus. There are three methods: E-mail, modem, and TCP / IP. Since the data transmission / reception sequence is basically the same, the case of E-mail will be described with reference to FIG. FIG. 11 is a flowchart showing a data transmission / reception sequence.

  First, a transmission sequence (which may be either a device management apparatus or a host apparatus here) will be described.

  When the transmission side satisfies the calling condition (A-501), the data to be transferred is attached to the E-mail and transmitted (A-502). A response is waited for the transmission data (A-503), and it is confirmed whether there is a response mail within a specified time (A-504). If there is a response, it is checked whether the response mail address matches that registered in advance (A-505). If it matches, the communication result is recorded in the database (A-506), and the sequence is completed. (A-507).

  When there is no response within a specified time while waiting for a response to transmission data (A-503) (A-504), a retransmission request is made (A-508). If the number of retransmissions is within the specified number, the data is retransmitted at (A-502). If the number of retransmissions exceeds the specified number, a warning mail is notified to the administrator (if the transmission side is a device management device, the user side administrator, and the transmission side is a host) (A-509) The communication result (error) is recorded on the database (A-506), and the process ends (A-507).

  Subsequently, a reception sequence will be described.

  The receiving side waits for receiving data (A-511), and when receiving (A-512), records the data on the database (A-513) and records it on the communication result database (A-514). The process ends (A-515).

<Control of host computer>
FIG. 12 is a configuration diagram of the host computer.

  A-801 is a CPU which controls the whole. A-802 is a RAM for storing programs and data necessary for the CPU to perform data processing. A-803 is a hard disk for storing received data, and all device management data is stored here.

  A-804 is a keyboard for an operator to give an instruction. A-805 is a display device for the host computer to output information. A-806 is a serial port for transmitting and receiving data to and from the modem. A-807 is a network board connected to the LAN, and A-808 is a mail server that exchanges data with the device management apparatus by E-mail.

  FIG. 13 is a flowchart showing processing of the host computer.

  Only the case of data transmission / reception by E-mail will be described. Usually, the host computer waits for an E-mail from the device management apparatus (A-902). If there is an incoming call, the password is checked (A-903, A-904), and the counter value and component counter are received (A-904). If the mail is correctly received, an OK mail is returned to the device management apparatus (A-905). If the mail is not correctly received, an error mail is transmitted (A-910). The encrypted mail attachment information is decrypted (A-906), and the counter value and component counter are stored in the hard disk (A-907). At this time, if the diagnosis result on the device side has reached the warning level, a warning is displayed on the display to notify the operator (A-909).

  Next, the life prediction of the mechanical drive system according to the feature of the present invention will be described. Since the stepping motor control technique is already known, details thereof are omitted.

  FIG. 3 is a block diagram showing a configuration for controlling the mechanical drive system using a stepping motor. Here, an optical system will be described as an example of a mechanical drive system employing a stepping motor, but the present invention is not limited to this.

  The CPU unit 150 outputs an excitation signal that is a target drive speed of the mechanical drive system to the motor driver 802. At the same time, the CPU unit 150 outputs current control data to a D / A converter 801 that converts analog data into analog data, and the D / A converter 801 outputs a reference voltage for setting an output current of the motor to the motor driver 802.

  As a result, the optical system stepping motor 803 is driven to transmit power to the mechanical drive system 804. The encoder 805 is attached to the opposite output shaft of the optical system stepping motor 803, and detects whether the mechanical drive system 804 is driven according to the excitation signal.

  Next, an increase in the load on the mechanical drive system due to changes over time will be described. FIG. 4 is a diagram showing an optical system for reading a document of the image forming apparatus.

  As described above, when the platen glass 102 is conveyed to a predetermined position, the second mirror base 106a constituting the scanner unit 104 and the mirrors 106 and 107 is moved on the slide rail 812 by the slide pins 801a, 1b, 1c, and 1d. Is driven in the direction indicated by the arrow in FIG. Normally, oil such as grease is applied on the slide rail 812 in order to make the movement of the slide pin 811 smooth. The dynamic resistance increases, and as a result, the load on the optical system stepping motor 813 increases.

  In addition, rollers 814a, 814b, 814c, 814d, 814e, 814f, 814g, and 814h, which are rotatably supported by a shaft fixed to an optical system housing (not shown), are moved by a reciprocating motion of the optical system, As a result, friction occurs in the sliding portion and the rotational torque of the roller increases, and as a result, the load on the optical system stepping motor 813 increases.

  Next, a method for predicting the lifetime of the mechanical drive system from the current value when the step-out of the optical system stepping motor 813 is detected will be described with reference to the flowchart of FIG. This sequence is executed by the CPU controlling based on a predetermined program stored in the ROM. The timing at which this sequence is executed may be any time such as when the image forming apparatus is turned on or every predetermined time.

  After powering on the image forming apparatus, the image forming apparatus performs an initial operation in order to check whether each load in the image forming apparatus is driven normally. At this time, for example, the above-described optical system reciprocates between the home position and a predetermined distance in FIG.

  During this reciprocating drive, the CPU 150 changes the set current so as to lower the output current of the optical system stepping motor 813 (S801). The set current is gradually decreased and the following processing is performed. At this time, if the output from the encoder 815 does not change (S802), it is determined that the optical system stepping motor 813 has stepped out and the motor cannot be driven, and the set current at that time is set as the stepping out current In (S803). ). The step-out current In is stored in the hard disk (HDD) 154 in the CPU circuit unit 150 (S804).

  This step-out detection is performed at a predetermined interval, and the step-out currents I1, I2, etc. at that time are sequentially stored in the HDD 154. The accumulated step-out current data is calculated by the HDD 154, and an approximate value graph is created in which time is plotted on the horizontal axis and current values are plotted on the vertical axis, as shown in FIG. Then, the slope of this graph is obtained from the values of I2 and I5, and the time TL until the current limit value IL is predicted. This current limit value IL is a maximum current (which satisfies both the motor and the motor driver, both ratings, temperature rise, and the like) that can flow through both the motor and the motor driver. If the current value when the step-out is detected becomes greater than or equal to IL, the mechanical drive system cannot be driven by the stepping motor, so that the time TL can be satisfied with the life of the mechanical drive system.

  Next, the timing for issuing a life alarm (life warning) will be described with reference to the flowchart of FIG. Ta2 in FIG. 6 is a value obtained by subtracting the minimum time required to procure the mechanical drive system unit subject to the lifetime from the limit time TL, and Ta1 is a value obtained by giving a predetermined margin time to Ta2. is there.

In FIG. 7, step-out detection is first performed (S901), and the time T at that time
Ta1 ≦ t <Ta2
If this is the case (S902), the CPU in the CPU circuit unit 150 transmits a lifespan alarm to the device management apparatus A-300 of FIG. 8 via the communication control unit 1001 and the network (S903). Further, it can be transmitted to the host A-800 using the Internet or the public line A-001. Thereafter, a life alarm is displayed on the operation unit of the image forming apparatus (S904), and the user can be warned.

  In the above description, the life prediction is performed by the image forming apparatus. However, the device management apparatus A-300 can perform the same life prediction. In this case, the step-out current data is transmitted to the HardDisk (A-303, A304) of the device management apparatus A-300 via the communication control unit 1001 and the network, and sequentially stored in the HardDisk (A-303, A304). Is done. The accumulated step-out current data is subjected to the same calculation as that performed by the HDD 154 in the image forming apparatus, and the life prediction is performed. Then, by displaying the prediction result on the display A-305 of the device management apparatus A-300, the network administrator can notify the service company before it is known to the general user.

  Furthermore, the same life prediction can be performed by the host management apparatus (A-800) HardDisk (A-803) via the Internet or a public line. By displaying this prediction result on the display A-305 of the device management apparatus A-300 and the display A-805 of the host A-800, the unit to be replaced and its timing can be grasped in advance, and service efficiency of the serviceman In addition, the inventory management of replacement units becomes easy.

  The present invention is applicable to a technique for predicting the lifetime of a mechanical drive system that is driven using a stepping motor in an image forming apparatus.

1 is a cross-sectional view illustrating a main part configuration of an image forming apparatus. 2 is a block diagram illustrating a configuration of a controller that controls the entire image forming apparatus. FIG. It is a block diagram which shows the structure which controls a mechanical drive system using a stepping motor. 1 is a diagram illustrating an optical system that reads a document of an image forming apparatus. It is a flowchart which shows the process which estimates the lifetime of the mechanical drive system controlled by a stepping motor. It is a figure which shows the graph which estimates the lifetime of a mechanical drive system. It is a flowchart which shows the timing which gives a lifetime alarm. It is a block diagram of the remote management system by a network. It is a block diagram of a device management apparatus. It is a flowchart which shows operation | movement of a device management apparatus. It is a flowchart which shows a data transmission / reception sequence. It is a block diagram of a host computer. It is a flowchart which shows the process of a host computer.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Image forming part 100 Automatic document feeder 150 CPU circuit part 200 Image reader 801 D / A converter 802 Motor driver 803 Optical system stepping motor 804 Mechanical drive system 805 Encoder 811 Slide pin 812 Slide rail 814 Roller 1001 Communication control part

Claims (8)

In an image forming apparatus management system having at least one image forming apparatus and a host device that manages the image forming apparatus via a network,
A stepping motor for driving a drive system in the image forming apparatus; drive control means for driving the stepping motor; current control means for changing an output current of the stepping motor; and output of the stepping motor by the current control means. A step-out detecting means for detecting step-out of the stepping motor by changing the current, and predicting the life of the drive system from the current value when the step-out detecting means detects the step-out of the stepping motor. An image forming apparatus management system.   The image forming apparatus according to claim 1, further comprising a storage unit that stores a current value at the time when the step-out is detected, and predicting a life of the drive system based on the current value stored in the storage unit. Device management system.   3. The image forming apparatus management system according to claim 1, wherein detection by the step-out detection unit is performed during an initial operation of the image forming apparatus or at a predetermined interval.   The image forming apparatus management system according to claim 1, further comprising a display unit, wherein the display unit displays a warning on a prediction result of the life of the drive system.   A stepping motor for driving a drive system in the apparatus; drive control means for driving the stepping motor; current control means for changing an output current of the stepping motor; and an output current of the stepping motor being changed by the current control means. A step-out detecting means for detecting step-out of the stepping motor, and predicting the life of the drive system from the current value when the step-out detecting means detects the step-out of the stepping motor. An image forming apparatus.   6. The image forming apparatus according to claim 5, further comprising a storage unit that stores a current value when the step-out is detected, and predicting a life of the drive system based on the current value stored in the storage unit. apparatus.   7. The image forming apparatus according to claim 5, wherein the detection by the step-out detection unit is performed during an initial operation of the image forming apparatus or at a predetermined interval.   The image forming apparatus according to claim 5, further comprising a display unit, wherein a warning result is displayed on the display unit for predicting a life of the drive system.

Images