Control system, image forming apparatus, and control method

Abstract

To enable the restart of controlled equipment even if a malfunction occurs in the main control unit. [Solution] The control system 20 includes one or more control units (drive control unit 22, UI control unit 23, power supply control unit 24) that individually control one or more functional units of the controlled device (image forming apparatus 100), and a main control unit 21 that controls one or more control units. The alternative control unit 30, which consists of at least one of the one or more control units, includes a sub-detection processing unit 301 and a sub-restart processing unit 302. The sub-detection processing unit 301 detects whether or not there is an abnormality in the main control unit 21. The sub-restart processing unit 302 restarts the main control unit 21 when the sub-detection processing unit 301 detects the occurrence of an abnormality in the main control unit 21.

Description

Technical Field

[0001] The present invention relates to a control system, an image forming apparatus, and a control method.

Background Art

[0002] As related art, an image forming apparatus including a main body that is a device to be controlled and an operation device is known (see, for example, Patent Document 1). In this image forming apparatus, when an abnormality occurs in communication between the device to be controlled and the operation device, the operation device is shut down, and the device to be controlled is restarted.

Related Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In the image forming apparatus shown in the related art described above, when an abnormality occurs in the CPU (Central Processing Unit) which is the main control unit of the device to be controlled, the main control unit does not operate normally, so there is a problem that the main control unit cannot be restarted.

[0005] An object of the present invention is to provide a control system, an image forming apparatus, and a control method capable of restarting a main control unit even when an abnormality occurs in the main control unit.

Means for Solving the Problems

[0006] A control system according to one aspect of the present invention comprises one or more control units that individually control one or more functional units of a controlled device, and a main control unit that controls the one or more control units. An alternative control unit consisting of at least one of the one or more control units comprises a sub-detection processing unit and a sub-restart processing unit. The sub-detection processing unit detects whether or not there is an abnormality in the main control unit. The sub-restart processing unit restarts the main control unit when the sub-detection processing unit detects the occurrence of an abnormality in the main control unit.

[0007] An image forming apparatus according to another aspect of the present invention is the controlled device comprising the control system described above and an image forming unit. The image forming unit is included in the one or more functional units and forms an image on a sheet.

[0008] Another aspect of the present invention relates to a control method for a control system comprising one or more control units that individually control one or more functional units of a device to be controlled, and a main control unit that controls the one or more control units. The control method includes detecting whether or not there is an abnormality in the main control unit. When the control method detects the occurrence of an abnormality in the main control unit, it includes instructing at least one of the one or more control units to restart the main control unit. [Effects of the Invention]

[0009] According to the present invention, it is possible to provide a control system, an image forming apparatus, and a control method that can restart the main control unit even if an abnormality occurs in the main control unit. [Brief explanation of the drawing]

[0010] [Figure 1] Figure 1 is a schematic block diagram showing the configuration of an image forming apparatus equipped with a control system according to an embodiment. [Figure 2] Figure 2 is a schematic diagram showing the external appearance of the image forming apparatus according to the embodiment. [Figure 3] Figure 3 is a schematic diagram showing an example of a restart operation by the main control unit in the control system according to the embodiment. [Figure 4] Figure 4 illustrates the problems in the control system of the comparative example. [Figure 5] Figure 5 is a schematic diagram showing an example of restart operation by the alternative control unit in the control system of the embodiment. [Figure 6] Figure 6 is a flowchart showing an example of the operation of the control system according to the embodiment. [Modes for carrying out the invention]

[0011] The embodiments of the present invention will be described below with reference to the attached drawings. The following embodiments are examples that embody the present invention and are not intended to limit the technical scope of the present invention.

[0012] [1] Overall configuration of the image forming apparatus First, the overall configuration of the image forming apparatus 100 according to this embodiment will be described with reference to Figures 1 and 2.

[0013] The image forming apparatus 100 according to this embodiment is, for example, a multifunction device having multiple functions such as a scanning function to acquire image data from a document, a printing function to form an image based on the image data, a facsimile function, and a copying function. The image forming apparatus 100 only needs to have an image processing function that includes at least one of the functions of forming an image and the function of acquiring image data, and may be a printer, scanner, facsimile device, or copier, etc.

[0014] As shown in Figure 1, the image forming apparatus 100 comprises an ADF 11, an image reading unit 12, an image forming unit 13, a paper feeding unit 14, a display unit 15, an operation unit 16, a storage unit 17, a communication unit 18, and an external I / F 19. The image forming apparatus 100 also comprises a control system 20 that controls the image forming apparatus 100. ADF 11 is an automatic document transport device and is an abbreviation for Auto Document Feeder. External I / F 19 is an abbreviation for External Interface.

[0015] In the present embodiment, as shown in FIG. 2, the image forming apparatus 100 includes a main body 101. The ADF 11, image reading unit 12, image forming unit 13, paper feeding unit 14, display unit 15, operation unit 16, storage unit 17, communication unit 18, external I / F 19, and control system 20 are all provided in the main body 101.

[0016] The ADF 11 conveys a document whose image is to be read by the image reading unit 12. The ADF 11 includes a document setting section, a plurality of conveying rollers, a document presser, a paper discharge section, and the like.

[0017] The image reading unit 12 reads an image from a document and outputs image data corresponding to the read image. The image reading unit 12 includes a document platen, a light source, a plurality of mirrors, an optical lens, a CCD (Charge Coupled Device), and the like.

[0018] The image forming unit 13 forms an image on a sheet by an electrophotographic method based on image data output from the image reading unit 12. Further, the image forming unit 13 forms an image on a sheet based on image data input from an information processing apparatus outside the image forming apparatus 100, such as a personal computer. The image forming unit 13 includes four image forming units corresponding to four colors of C (cyan), M (magenta), Y (yellow), and K (black), an optical scanning device, an intermediate transfer belt, a secondary transfer roller, a fixing device, and the like. The image forming unit 13 may be configured to form an image on a sheet by an image forming method other than the electrophotographic method, such as an inkjet method.

[0019] The image forming unit 13 forms an image on a sheet using toner as a developer. When the image forming unit 13 forms an image by an inkjet method, ink (another example of the developer) is supplied instead of toner. Examples of the toner supplied to the image forming unit 13 include toners of a plurality of colors including C (cyan), M (magenta), Y (yellow), and K (black). The sheet after image formation in the image forming unit 13 is discharged (supplied) to an extended device or the like for post-processing.

[0020] The sheet feeding unit 14 supplies sheets to the image forming unit 13. The sheet feeding unit 14 includes a sheet feeding cassette, a manual feed tray, a sheet conveyance path, a plurality of conveyance rollers, and the like. The image forming unit 13 forms an image on a sheet supplied from the sheet feeding unit 14. The sheet supplied to the image forming unit 13 is paper as an example, but is not limited to paper, and may be, for example, a resin film or the like.

[0021] The display unit 15 is a user interface unit (hereinafter also referred to as a "UI (User Interface) unit") for presenting (displaying) information to a user in the image forming apparatus 100. The display unit 15 displays various types of information in response to control instructions from the control system 20. In the present embodiment, as an example, the display unit 15 includes a liquid crystal display, and displays a display screen including various types of information on the liquid crystal display.

[0022] The operation unit 16 is, for example, a user interface for receiving an operation input by a user on a display screen displayed on the display unit 15. The operation unit 16 receives various operations by the user by outputting an electric signal corresponding to the user's operation, for example. In the present embodiment, as an example, the operation unit 16 includes a switch, a key or a numeric keypad, a touch panel, and the like.

[0023] Further, the image forming apparatus 100 may include, as the UI unit, in addition to or instead of the display unit 15 and the operation unit 16, for example, an audio output unit, an audio input unit, and the like.

[0024] The storage unit 17 stores in advance information such as control programs for causing the control system 20 to execute various processes. In the present embodiment, the storage unit 17 includes one or more nonvolatile memories such as a ROM (Read Only Memory), an HDD (Hard Disk), or an SSD (Solid State Disk). The storage unit 17 also includes one or more volatile memories such as a RAM (Random Access Memory).

[0025] The communication unit 18 is an interface that performs data communication between the image forming apparatus 100 and an external system connected via a communication network such as the Internet or a LAN (Local Area Network). The data communication may be wired or wireless. The data communication may also be wireless communication conforming to a short-range wireless communication standard such as NFC (Near Field Communication) (registered trademark) or Bluetooth (registered trademark).

[0026] External I / F19 has a port to which an external memory or external device is connected, and is an interface for performing data communication with the external memory or external device connected to the port. In this embodiment, the external memory includes, for example, a USB (Universal Serial Bus) memory. The external device includes, for example, a USB mass storage compatible device. The external memory may also include, for example, an HDD or SSD.

[0027] The control system 20 primarily consists of a computer system having one or more processors and one or more memories, and comprehensively controls the image forming apparatus 100. In the image forming apparatus 100, the functions of the control system 20 are realized by one or more processors executing programs. In this embodiment, as an example, the control system 20 includes a CPU (Central Processing Unit).

[0028] The program may be pre-recorded in one or more memories, provided via a telecommunications line such as the Internet, or provided on a non-temporary recording medium readable by a computer system, such as a memory card or optical disc. One or more processors consist of one or more electronic circuits including semiconductor integrated circuits. Furthermore, the computer system referred to herein includes a microcontroller having one or more processors and one or more memories.

[0029] The control system 20 comprises one or more control units that individually control one or more functional units of the image forming apparatus 100, which is the controlled device, and a main control unit 21 that controls the one or more control units. In this embodiment, the one or more control units include a drive control unit 22, a user interface control unit (hereinafter also referred to as the "UI control unit") 23, and a power supply control unit 24. Note that the one or more control units are not limited to the drive control unit 22, the UI control unit 23, and the power supply control unit 24, and may include other control units.

[0030] The drive control unit 22 controls one or more motors (not shown) which are functional units of the image forming apparatus 100. For example, the drive control unit 22 rotates the multiple transport rollers of the ADF 11 and paper feeding unit 14 by driving one or more motors according to control instructions from the main control unit 21. Also, for example, the drive control unit 22 rotates the image carrier, such as the intermediate transfer belt, of the image forming unit 13 by driving one or more motors according to control instructions from the main control unit 21. Also, for example, the drive control unit 22 moves the reading unit of the image reading unit 12, which is equipped with a light source and multiple mirrors, by driving one or more motors according to control instructions from the main control unit 21.

[0031] The UI control unit 23 controls the display unit 15 and the operation unit 16, which are functional units of the image forming apparatus 100. For example, the UI control unit 23 controls the display unit 15 according to control instructions from the main control unit 21, thereby displaying various screens on the display unit 15. Also, for example, the UI control unit 23 transmits signals to the main control unit 21 corresponding to operations received by the operation unit 16.

[0032] The power control unit 24 controls the power supply (not shown), which is one of the functional units of the image forming apparatus 100. For example, the power control unit 24 performs the following actions in accordance with control instructions from the main control unit 21: turning off the power to the controlled device (in this case, the image forming apparatus 100), putting the power supply into sleep mode, and restarting the power supply.

[0033] The main control unit 21 comprehensively controls one or more control units (in this case, the drive control unit 22, the UI control unit 23, and the power supply control unit 24) by communicating with each of them. Specifically, the main control unit 21 causes the drive control unit 22 to drive one or more motors by sending control instructions to the drive control unit 22. The main control unit 21 also monitors the state of drive control by the drive control unit 22 by receiving signals from the drive control unit 22 that indicate the state of the drive control unit 22.

[0034] Furthermore, the main control unit 21 causes the UI control unit 23 to control the display unit 15 by transmitting control instructions to the UI control unit 23. Also, when the main control unit 21 receives a signal corresponding to an operation received by the operation unit 16 transmitted from the UI control unit 23, it executes control according to that signal. In addition, the main control unit 21 monitors the status of UI control by the UI control unit 23 by receiving a signal indicating the status of the UI control unit 23 transmitted from the UI control unit 23.

[0035] Furthermore, the main control unit 21 transmits control instructions to the power supply control unit 24, causing the power supply control unit 24 to control the power supply of the controlled device (in this case, the image forming apparatus 100).

[0036] In this embodiment, the main control unit 21 has a function to display an error code on the display unit 15 corresponding to the abnormality that occurs in one or more control units due to, for example, deterioration, failure, or lifespan of a component. For example, as shown in Figure 3 <Component deterioration / failure / lifespan>, suppose an abnormality occurs in the drive control unit 22 due to a failure. In this case, when the main control unit 21 receives a signal indicating the status of the drive control unit 22, it instructs the UI control unit 23 to display an error code corresponding to the abnormality. The UI control unit 23 then controls the display unit 15 to display the error code. As a result, the user can understand that an abnormality has occurred in the drive control unit 22 and how to deal with the abnormality by looking at the error code displayed on the display unit 15.

[0037] Furthermore, in this embodiment, the main control unit 21 has a function to restart the control unit that has malfunctioned by restarting the power supply if a malfunction occurs in one or more control units due to temporary external factors such as noise or temperature. Specifically, as shown in Figure 1, the main control unit 21 has a main detection processing unit 211 and a main restart processing unit 212, thereby realizing the above function.

[0038] The main detection processing unit 211 detects whether or not there is an abnormality in one or more control units. Specifically, the main detection processing unit 211 detects whether or not an abnormality due to a temporary external factor has occurred in one or more control units based on the state of each of the one or more control units. For example, if communication with one or more control units is interrupted, the main detection processing unit 211 detects that an abnormality due to a temporary external factor has occurred in that control unit. More specifically, if the main detection processing unit 211 sends a control instruction to one or more control units, and no response signal to the control instruction is returned even after a predetermined time has elapsed since the transmission of the control instruction, it determines that communication with that control unit has been interrupted.

[0039] Furthermore, the main detection processing unit 211 may periodically send a request instruction to each of one or more control units requesting a response signal, and if there is a control unit that does not respond, it may detect that a temporary abnormality due to an external factor has occurred in that control unit.

[0040] The main restart processing unit 212 restarts a control unit when the main detection processing unit 211 detects that an abnormality has occurred in at least one of the control units among the one or more control units. Specifically, when the main detection processing unit 211 detects an abnormality, the main restart processing unit 212 instructs the power supply control unit 24 to restart the power. The power supply control unit 24 then restarts the power by turning the power off and then on again. This restarts the image forming apparatus 100, and consequently the control unit that is experiencing an abnormality due to a temporary external factor is restarted. If the external factor has disappeared, the control unit returns to a normal operating state. Furthermore, since the above restart process is executed automatically when an abnormality is detected in any of the control units, the user does not need to perform a power restart operation, making it user-friendly.

[0041] For example, as shown in Figure 3 under <External Factors>, suppose a temporary malfunction occurs in the drive control unit 22 due to an external factor. In this case, the main control unit 21 detects that a malfunction has occurred in the drive control unit 22 when communication with the drive control unit 22 is interrupted. The main control unit 21 then instructs the power supply control unit 24 to restart the power supply. The power supply control unit 24 then restarts the power supply. As a result, the image forming apparatus 100 restarts, and the drive control unit 22 also restarts, so if the external factor has disappeared, the drive control unit 22 returns to a normal operating state. The above restart is also performed, for example, if a temporary malfunction occurs in the UI control unit 23 due to an external factor.

[0042] Incidentally, a related technology known is an image forming apparatus comprising a main unit, which is the controlled device, and an operating device. In this image forming apparatus, if an abnormality occurs in communication between the controlled device and the operating device, the operating device is shut down and the controlled device is restarted.

[0043] In the image forming apparatus described in the related technologies above, there is a problem in that if an abnormality occurs in the CPU, which is the main control unit of the controlled device, the main control unit will not operate normally, and therefore it will not be possible to restart the main control unit.

[0044] The above problems will now be explained in detail with reference to the control system 200 of the comparative example. The control system 200 of the comparative example is installed in the image forming apparatus 100, which is the controlled device, and as shown in Figure 4, it comprises a main control unit 201, a drive control unit 202, a UI control unit 203, and a power supply control unit 204. The main control unit 201, drive control unit 202, UI control unit 203, and power supply control unit 204 all have the same functions as the main control unit 21, drive control unit 22, UI control unit 23, and power supply control unit 24 described above. However, the control system 200 of the comparative example does not have a configuration equivalent to the alternative control unit 30 (see Figure 1) which will be described later.

[0045] For example, suppose a temporary malfunction occurs in the main control unit 201 due to an external factor. In this case, because the main control unit 201 is malfunctioning, it cannot operate normally. Therefore, the main control unit 201 cannot detect that a malfunction has occurred in it, and naturally, it cannot instruct the power supply control unit 204 to restart the power supply. Consequently, in the example shown in Figure 4, even if the external factor disappears, the malfunctioning state of the main control unit 201 will continue.

[0046] In this case, the user will only realize that there is a problem with the image forming apparatus 100 when they observe symptoms such as the display unit 15 remaining fixed and not responding to the operation unit 16. The user will then have to restart the image forming apparatus 100 by manually turning its power on and off.

[0047] In the comparative example control system 200, it is conceivable to add, for example, a circuit or mechanism to remove noise and a mechanism to maintain the temperature below a predetermined temperature, in order to prevent abnormalities caused by temporary external factors. However, adding such mechanisms would create a new problem: a significant increase in manufacturing costs. Furthermore, even with such mechanisms added, it would be difficult to address all external factors.

[0048] In contrast, in this embodiment, the control system 20, image forming apparatus 100, and control method can be realized in which the main control unit 21 can be restarted even if an abnormality occurs in the main control unit 21, through the processing performed by the control system 20 described below.

[0049] [2] Control system configuration The following describes in more detail each functional unit included in the control system 20 with reference to Figure 1. The control system 20 comprises an alternative control unit 30 consisting of at least one control unit from among one or more control units (here, the drive control unit 22 or the UI control unit 23), and a logical OR circuit 25 (see Figure 5). The alternative control unit 30 also includes a sub-detection processing unit 301 and a sub-restart processing unit 302.

[0050] In this embodiment, the UI control unit 23 that controls the display unit 15, which is the UI unit, functions as the alternative control unit 30. In other words, one or more functional units include a UI unit (in this case, a display unit 15). The alternative control unit 30 includes the UI control unit 23 that controls the UI unit.

[0051] The sub-detection processing unit 301 detects whether or not there is an abnormality in the main control unit 21. When an abnormality occurs in the main control unit 21, the main restart processing unit 212 of the main control unit 21 cannot send a power restart instruction to the power control unit 24. In other words, the sub-detection processing unit 302 detects the inability of the main restart processing unit 212 to restart as an abnormality in the main control unit 21. Specifically, the sub-detection processing unit 301 detects the occurrence of an abnormality in the main control unit 21 when communication between the alternate control unit 30 and the main control unit 21 is interrupted. More specifically, the alternate control unit 30 sends a signal to the main control unit 21 indicating the status of the alternate control unit 30, and if no response signal (control instruction) to the signal is returned even after a predetermined time has elapsed since the transmission of the signal, it is determined that communication with the main control unit 21 has been interrupted. When communication with the main control unit 21 is interrupted, the sub-detection processing unit 301 detects that an abnormality has occurred in the main control unit 21 due to a temporary external factor.

[0052] For example, in this embodiment, if the UI control unit 23 is an alternative control unit 30, the UI control unit 23 transmits a signal to the main control unit 21 corresponding to the operation received by the operation unit 16. If the main control unit 21 is operating normally, it transmits a response signal (control instruction) to the UI control unit 23 in response to the signal. However, if an abnormality occurs, it cannot transmit the response signal to the UI control unit 23. Therefore, the UI control unit 23 can detect whether or not an abnormality due to a temporary external factor has occurred in the main control unit 21 at the time it receives an operation from the operation unit 16 as described above.

[0053] Furthermore, the sub-detection processing unit 301 may periodically send a request instruction to the main control unit 21 requesting a response signal, and if no response signal is received, it may detect that an abnormality due to a temporary external factor has occurred in the main control unit 21.

[0054] Furthermore, the sub-detection processing unit 301 may detect whether or not an abnormality due to a temporary external factor has occurred in the main control unit 21 by means other than those described above. For example, the sub-detection processing unit 301 may detect whether or not an abnormality due to a temporary external factor has occurred in the main control unit 21 based on the output value of the signal line connecting the main control unit 21 and the alternate control unit 30. Specifically, the main control unit 21 is configured to transmit an output value indicating the operating status of the main control unit 21 to the alternate control unit 30 via the signal line. The output value is binary; for example, an output value of "1" indicates that the main control unit 21 is operating normally, and an output value of "0" indicates that an abnormality has occurred in the main control unit 21.

[0055] Therefore, the sub-detection processing unit 301 detects that no abnormality due to a temporary external factor has occurred in the main control unit 21 as long as the output value of the signal line is "1". Conversely, the sub-detection processing unit 301 detects that an abnormality due to a temporary external factor has occurred in the main control unit 21 when the output value of the signal line is "0".

[0056] The sub-restart processing unit 302 restarts the main control unit 21 when the sub-detection processing unit 301 detects an abnormality in the main control unit 21. Specifically, when the sub-detection processing unit 301 detects an abnormality, the sub-restart processing unit 302 instructs the power supply control unit 24 to restart the power. The power supply control unit 24 then restarts the power by turning the power off and then on again. This restarts the image forming apparatus 100, and consequently the main control unit 21, which is experiencing an abnormality due to a temporary external factor, is also restarted. If the external factor has disappeared, the main control unit 21 will return to a normal operating state. Furthermore, since the above restart process is executed automatically when an abnormality in the main control unit 21 is detected, the user does not need to perform a power restart operation, making it user-friendly.

[0057] As shown in Figure 5, the OR circuit 25 is configured to send a power restart instruction to the power control unit 24 when at least one of the following is input: a power restart instruction from the main control unit 21 or a power restart instruction from the alternate control unit 30. On the other hand, the OR circuit 25 does not send a power restart instruction to the power control unit 24 if no power restart instruction is input from either the main control unit 21 or the alternate control unit 30. This allows the power control unit 24 to send a power restart instruction whether the main control unit 21 detects an abnormality in one or more control units, or whether the alternate control unit 30 detects an abnormality in the main control unit 21.

[0058] The operation example of the alternate control unit 30 will be explained below with reference to Figure 5. As shown in Figure 5, suppose an abnormality occurs in the main control unit 21 due to a temporary external factor. In this case, the main control unit 21 cannot send an instruction to the power supply control unit 24 to restart the power supply because an abnormality has occurred. On the other hand, the sub-detection processing unit 301 of the alternate control unit 30 (here, the UI control unit 23) detects that an abnormality has occurred in the main control unit 21, for example, when communication with the main control unit 21 is interrupted. The sub-restart processing unit 302 of the alternate control unit 30 then instructs the power supply control unit 24 to restart the power supply via the OR circuit 25. The power supply control unit 24 then restarts the power supply. As a result, the image forming apparatus 100 restarts, and the main control unit 21 also restarts, so if the external factor has disappeared, the main control unit 21 returns to a normal operating state.

[0059] In this embodiment, since the UI control unit 23 functions as an alternate control unit 30, the UI control unit 23 can notify the UI unit (in this case, the display unit 15) that the sub-restart processing unit 302 has restarted the main control unit 21. Specifically, the UI control unit 23 displays a message or image on the display unit 15, for example, "A temporary abnormality such as noise occurred, so a restart was performed." This allows the user to understand why the main control unit 21 was restarted (in this case, the image forming apparatus 100, which is the controlled device).

[0060] If the UI unit is equipped with a speaker, the UI control unit 23 may notify the sub-restart processing unit 302 that the main control unit 21 has been restarted by outputting sound from the speaker.

[0061] By the way, if the main control unit 21 experiences an abnormality not due to a temporary external factor, but rather due to, for example, deterioration, failure, or end of life of a component, restarting the main control unit 21 will not restore it to a normal operating state. In this case, the backup control unit 30 will continue to repeatedly restart the main control unit 21 unnecessarily. Also, if there is a connection problem between the main control unit 21 and other control units, the backup control unit 30 will continue to repeatedly restart the main control unit 21 unnecessarily, even if the main control unit 21 is in a normal operating state.

[0062] Therefore, in this embodiment, the sub-restart processing unit 302 stops restarting the main control unit 21 when the number of restarts of the main control unit 21 satisfies specific conditions. The specific conditions may include, for example, that the number of restarts of the main control unit 21 reaches a predetermined number (e.g., several times). The specific conditions may also include, for example, that the number of restarts of the main control unit 21 reaches a predetermined number (e.g., several times) within a predetermined period (e.g., several minutes). The specific conditions may also include, for example, that the number of restarts of the main control unit 21 is multiple, and the interval between restarts is a predetermined time (e.g., several seconds).

[0063] Specifically, when the sub-restart processing unit 302 sends a power restart instruction to the power control unit 24, it counts the number of power restart instructions sent each time thereafter. Then, when the counted number of power restart instructions (i.e., the number of restarts of the main control unit 21) meets a specific condition, the sub-restart processing unit 302 stops sending power restart instructions to the power control unit 24. As a result, the restart of the main control unit 21 stops when the specific condition is met, making it possible to prevent unnecessary restarts of the main control unit 21 from being repeated.

[0064] Furthermore, in this embodiment, the sub-restart processing unit 302 notifies the user when it stops restarting the main control unit 21 due to the fulfillment of specific conditions as described above. Specifically, the sub-restart processing unit 302 sends a signal to the UI control unit 23 indicating that it has stopped restarting the main control unit 21. The UI control unit 23 then displays a message or image on the display unit 15, for example, "The restart has been stopped because it has been restarted multiple times." This allows the user to understand that the restart of the main control unit 21 (in this case, the restart of the image forming apparatus 100, which is the controlled device) has been stopped. The user can also indirectly understand from this notification that the abnormality has not been resolved even if the restart of the main control unit 21 has been repeated multiple times. Therefore, the user can take measures against the unresolved abnormality, for example, by contacting a service provider that is repairing the controlled device (in this case, the image forming apparatus 100).

[0065] If the UI unit is equipped with a speaker, the UI control unit 23 may notify the main control unit 21 that the restart has been stopped by outputting sound from the speaker.

[0066] [3] Example of control system operation Hereinafter, with reference to Figure 6, an example of a control method for the control system 20 of this embodiment will be described along with an example of a procedure for processing performed by the control system 20. Here, steps S11, S12, ... represent the numbers of processing procedures (steps) performed by the control system 20. This processing is performed, for example, during the operation of a controlled device (in this case, an image forming apparatus 100) equipped with the control system 20.

[0067] <Step S11> The main detection processing unit 211 of the main control unit 21 detects whether or not there is an abnormality in one or more control units (in this case, the drive control unit 22 or the UI control unit 23). Specifically, the main detection processing unit 211 detects whether or not an abnormality has occurred in one or more control units due to a temporary external factor, based on the state of each of the one or more control units. If the main detection processing unit 211 detects that an abnormality has occurred in any of the control units (step S11: Yes), the control system 20 executes step S12. On the other hand, if the main detection processing unit 211 detects that no abnormality has occurred in any of the control units, or if the main control unit 21 is not in a normal operating state (step S11: No), the control system 20 executes step S14.

[0068] <Step S12> The main restart processing unit 212 of the main control unit 21 sends a power supply restart instruction to the power supply control unit 24 in order to restart the control unit that has been detected by the main detection processing unit 211 as having an abnormality.

[0069] <Step S13> When the power control unit 24 receives an instruction to restart the power supply from the main control unit 21 or the alternate control unit 30, it restarts the power supply by turning the power off and then turning the power on again.

[0070] <Step S14> The sub-detection processing unit 301 of the substitute control unit 30 detects whether or not there is an abnormality in the main control unit 21. Specifically, the sub-detection processing unit 301 detects whether or not an abnormality has occurred in the main control unit 21 due to a temporary external factor, based on whether or not communication with the main control unit 21 has been interrupted. If the sub-detection processing unit 301 detects that an abnormality has occurred in the main control unit 21 (step S14: Yes), the control system 20 executes step S15. On the other hand, if the sub-detection processing unit 301 detects that no abnormality has occurred in the main control unit 21 (step S14: No), the control system 20 executes step S11.

[0071] <Step S15> The sub-restart processing unit 302 of the alternate control unit 30 sends a power supply restart instruction to the power supply control unit 24 in order to restart the main control unit 21, which has been detected by the sub-detection processing unit 301 as having an abnormality.

[0072] Please note that the procedure described above is merely one example, and the order of the processes shown in the flowchart in Figure 6 may be changed as appropriate.

[0073] As described above, in the control system 20 according to this embodiment, the alternate control unit 30 detects whether or not there is an abnormality in the main control unit 21. When the alternate control unit 30 detects that an abnormality has occurred in the main control unit 21, it restarts the main control unit 21. Therefore, in this embodiment, even if an abnormality occurs in the main control unit 21 and the main control unit 21 is unable to operate normally, the alternate control unit 30 performs the restart process on behalf of the main control unit 21, making it possible to restart the main control unit 21.

[0074] Furthermore, in the control system 20 according to this embodiment, under normal conditions where no abnormality due to temporary external factors occurs in the main control unit 21, the main control unit 21 can restart any control unit even if an abnormality due to temporary external factors occurs in that control unit. In exceptional conditions where an abnormality occurs in the main control unit 21, the alternate control unit 30 can restart the main control unit 21. In other words, in the control system 20 according to this embodiment, even if an abnormality due to temporary external factors occurs in any of the main control unit 21 or one or more control units, the system can be restored to a normal operating state by restarting that control unit.

[0075] Furthermore, in the control system 20 according to this embodiment, it is not necessary to add, for example, a circuit or mechanism to remove noise and a mechanism to maintain the temperature below a predetermined temperature, in order to suppress the occurrence of abnormalities due to temporary external factors. Therefore, the control system 20 according to this embodiment has the advantage that it does not result in an increase in manufacturing costs due to the addition of the above-mentioned mechanisms.

[0076] [Differentiation] In this embodiment, the UI control unit 23 among one or more control units functions as the alternative control unit 30, but this is not limited to this. For example, a control unit other than the UI control unit 23, such as the drive control unit 22, may function as the alternative control unit 30. Also, the number of control units that function as the alternative control unit 30 is not limited to one, but may be multiple. For example, both the drive control unit 22 and the UI control unit 23 may function as the alternative control unit 30.

[0077] In this embodiment, the control system 20 is configured such that the power restart instruction from the alternate control unit 30 and the power restart instruction from the main control unit 21 are input to the OR circuit 25, but it is not limited to this configuration. For example, the control system 20 may be configured such that the power restart instruction from the alternate control unit 30 and the power restart instruction from the main control unit 21 are individually input to the power supply control unit 24. In this case, the control system 20 does not need to have the OR circuit 25. Note that if the control system 20 has the OR circuit 25, there is an advantage in that only one signal is input to the power supply control unit 24, so the number of input ports required in the power supply control unit 24 is only one.

[0078] In the above embodiment, the sub-restart processing unit 302 notifies the UI unit (in this case, the display unit 15) that it has restarted the main control unit 21, but this is not the only way. For example, the processing result of the restart of the main control unit 21 by the sub-restart processing unit 302 may be stored in the storage unit 17 as the execution history of various processes of the controlled device (in this case, the image forming apparatus 100). In this case, the user can understand that the main control unit 21 has been restarted by checking the execution history.

[0079] [Notes on the invention] The following is an overview of the invention extracted from the above-described embodiments. Note that each configuration and processing function described below can be selected and combined as desired.

[0080] <Note 1> One or more control units that individually control one or more functional units of the controlled device, The system comprises a main control unit that controls the one or more control units, An alternative control unit consisting of at least one control unit from the one or more control units described above is: A sub-detection processing unit that detects whether or not there is an abnormality in the main control unit, The system includes a sub-restart processing unit that restarts the main control unit when the sub-detection processing unit detects an abnormality in the main control unit. Control system.

[0081] <Note 2> The main control unit is, A main detection processing unit that detects whether or not there is an abnormality in the one or more control units, The system includes a main restart processing unit that restarts at least one of the one or more control units when the main detection processing unit detects an abnormality in that control unit, The sub-detection processing unit detects a state in which the main restart processing unit cannot perform a restart as an abnormality of the main control unit. The control system described in Appendix 1.

[0082] <Note 3> The sub-detection processing unit detects the occurrence of an abnormality in the main control unit when communication between the alternative control unit and the main control unit is interrupted. The control system described in Appendix 1 or 2.

[0083] <Note 4> The one or more functional units mentioned above include a user interface unit. The alternative control unit includes a user interface control unit that controls the user interface unit, The user interface control unit notifies the user interface unit that the sub-restart processing unit has restarted the main control unit. A control system as described in any one of the appendices 1 to 3.

[0084] <Note 5> The sub-restart processing unit stops restarting the main control unit when the number of restarts of the main control unit satisfies a specific condition. A control system described in any one of the appendices 1 to 4.

[0085] <Note 6> The alternative control unit will notify if the restart of the main control unit is stopped. The control system described in Appendix 5.

[0086] <Note 7> The aforementioned controlled device, A control system described in any one of the appendices 1 to 6, The system includes one or more of the above-mentioned functional units, and comprises an image forming unit that forms an image on a sheet. Image forming apparatus.

[0087] <Note 8> One or more control units that individually control one or more functional units of the controlled device, A control method for a control system comprising a main control unit that controls one or more of the aforementioned control units, To detect whether or not there is an abnormality in the main control unit, The system includes, when it detects an abnormality in the main control unit, instructing at least one of the one or more control units to restart the main control unit. Control method. [Explanation of Symbols]

[0088] 100 Image forming apparatus (controlled equipment) 13 Image forming unit 15 Display section (UI section) 20 Control Systems 21 Main Control Unit 211 Main detection processing unit 212 Main Restart Processing Unit 23 UI Control Unit 30 Alternative Control Unit 301 Sub-detection processing unit 302 Sub-reboot processing unit

Claims

1. One or more control units that individually control one or more functional units of the controlled device, The system comprises a main control unit that controls the one or more control units, The alternative control unit, which consists of at least one control unit from the one or more control units described above, A sub-detection processing unit that detects whether or not there is an abnormality in the main control unit, The system includes a sub-restart processing unit that restarts the main control unit when the sub-detection processing unit detects an abnormality in the main control unit. Control system.

2. The main control unit is, A main detection processing unit that detects whether or not there is an abnormality in the one or more control units, The system includes a main restart processing unit that restarts at least one of the one or more control units when the main detection processing unit detects an abnormality in that control unit. The sub-detection processing unit detects a state in which the main restart processing unit cannot perform a restart as an abnormality of the main control unit. The control system according to claim 1.

3. The sub-detection processing unit detects the occurrence of an abnormality in the main control unit when communication between the alternative control unit and the main control unit is interrupted. The control system according to claim 1 or 2.

4. The one or more functional units mentioned above include a user interface unit. The alternative control unit includes a user interface control unit that controls the user interface unit, The user interface control unit notifies the user interface unit that the sub-restart processing unit has restarted the main control unit. The control system according to claim 1 or 2.

5. The sub-restart processing unit stops restarting the main control unit when the number of restarts of the main control unit satisfies a specific condition. The control system according to claim 1 or 2.

6. The alternative control unit will notify if the restart of the main control unit is stopped. The control system according to claim 5.

7. The aforementioned controlled device, A control system according to claim 1 or 2, The above-mentioned one or more functional units include an image forming unit that forms an image on a sheet, Image forming apparatus.

8. One or more control units that individually control one or more functional units of the controlled device, A control method for a control system comprising a main control unit that controls one or more of the aforementioned control units, To detect whether or not there is an abnormality in the main control unit, The system includes, when it detects an abnormality in the main control unit, instructing at least one of the one or more control units to restart the main control unit. Control method.

Images