JP5766231B2 - Image forming apparatus - Google Patents

Description

  The present invention relates to communication control in an image forming apparatus that forms an image on a recording material.

  Conventionally, an image forming apparatus having a video controller and an engine control unit as control means is known. The video controller and the engine control unit can communicate with each other, and when the engine control unit detects that the state of the image forming apparatus has changed, the engine control unit notifies the video controller of the occurrence of the state change. Then, the video controller notified of the occurrence of the state change performs synchronization control between the video controller and the engine control unit by acquiring specific change information of the image forming apparatus. For example, in Patent Document 1, the state change notification signal is used to notify the video controller that the state in the image forming apparatus has changed, and the notified video controller notifies the state change in the image forming apparatus. A method for identifying status is disclosed.

JP-A-9-185294

  When the engine control unit and the video controller can always communicate with each other by the method as described in Patent Document 1, the state change of the image forming apparatus can be shared in real time. However, some recent image forming apparatuses have a power saving mode in which standby power is set to 1 W or less, for example. During the power saving mode, communication between the engine control unit and the video controller is interrupted in order to reduce standby power. When such communication is interrupted, the engine controller and the video controller cannot be synchronized. For example, it is assumed that the power saving mode is entered when the paper feed cassette status is detected, and the paper feed cassette is removed and then attached again during the power saving mode. When the power saving mode ends in this state, there is a problem that it may be detected only that the status of the paper feeding cassette is present, and it may not be possible to detect that the paper feeding cassette is attached or detached during the power saving mode.

  The invention according to the present application has been made in view of the above-described situation, and the engine control unit and the video are also changed with respect to the state change of the image forming apparatus when communication between the engine control unit and the video controller is interrupted. It is intended to control so that it can be shared by the controller.

To achieve the above object, can communicate with the controller for controlling the image information for image forming, an image forming apparatus having an engine control unit for controlling the image forming operation, the engine control and the controller A memory that stores information indicating that the state has changed when it is detected that the state when the communication is interrupted is changed from the state before the communication is interrupted when the communication with the unit is interrupted. And when the engine control unit recovers from the interruption of communication with the controller, the storage unit does not receive a request for notification of the state change generated when the communication is interrupted from the controller. based on the information stored in, does not indicate the contents of the status change of the image forming apparatus, the state of the image forming apparatus indicating whether or not a state change has occurred strange Information on and notifies the controller.

  According to the configuration of the present invention, the state change of the image forming apparatus when the communication between the engine control unit and the video controller is interrupted can be shared by the engine control unit and the video controller.

Schematic configuration diagram of an image forming apparatus A block diagram showing a hardware configuration for controlling the operation of the image forming apparatus and a control system comprising the functions The figure which showed the communication state of the engine control part 103 and the video controller 102 Schematic configuration of the paper cassette 301 A flowchart for explaining communication between the video controller 102 and the engine control unit 103 in the first embodiment. Time chart showing the communication state and status change between the video controller 102 and the engine control unit 103 in the first embodiment A flowchart for explaining communication between the video controller 102 and the engine control unit 103 in the second embodiment. Table showing initial values of state change status when communication between video controller 102 and engine control unit 103 is interrupted Time chart showing the communication state and status change between the video controller 102 and the engine control unit 103 in the second embodiment A flowchart for explaining communication between the video controller 102 and the engine control unit 103 in the third embodiment.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. The following embodiments do not limit the invention according to the claims, and all combinations of features described in the embodiments are not necessarily essential to the solution means of the invention.

(First embodiment)
FIG. 1 shows a schematic configuration diagram of an image forming apparatus according to the present embodiment. When a laser beam printer 101 as an image forming apparatus receives a print instruction from the video controller 102 shown in FIG. In order to feed the recording material S from the paper feed cassette 301, the paper feeding roller 307 is driven to send the recording material S to the transport path. The fed recording material S is conveyed by the conveyance roller 1005 and the conveyance roller 1006 and conveyed to the registration roller 1007. Thereafter, the top sensor 1008 detects the leading edge of the recording material S, and the recording material S is conveyed to the image forming unit 111. During continuous printing, the top sensor 1008 performs control to maintain the throughput by feeding the next recording material S a predetermined time after detecting the leading edge or the trailing edge of the recording material S.

  The image forming unit 111 includes a photosensitive drum 1009, a transfer roller 1010, a charging roller 1011, and a developing device 1012. After the photosensitive drum 1009 is uniformly charged by the charging roller 1011, the surface of the photosensitive drum 1009 is irradiated with a laser beam L corresponding to a VIDEO signal 107 shown in FIG. Is formed. The electrostatic latent image formed in this way is visualized as a toner image with toner attached thereto by the developing device 1012. Then, the photosensitive drum 1009 rotates and the toner image is conveyed to the transfer position. In synchronization with the rotation of the photosensitive drum 1009, the recording material S is also conveyed to the transfer position.

  At the transfer position, a voltage having a reverse polarity to the toner image is applied to the transfer roller 1010, and the toner image on the photosensitive drum 1009 is transferred to the recording material S. The recording material S to which the toner image has been transferred is conveyed to the fixing control unit 109 and is heated and pressurized to fix the toner image on the recording material S. The recording material S on which the toner image is fixed is conveyed through a triple roller 1016, an intermediate discharge roller 1017, and a discharge roller 1018, and is discharged onto a discharge tray 1021 to complete a series of printing operations. These series of processes are controlled by an engine control unit 103 described later. Although a monochrome image forming apparatus has been described here, the present invention can also be used for a color image forming apparatus.

Next, FIG. 2 is a block diagram showing a hardware configuration for controlling the operation of the image forming apparatus and a control system having the functions. The engine control unit 103 includes an arithmetic processing circuit, a ROM, a RAM, and the like, and an operation is realized based on a program written in advance in the ROM. Then, a print instruction or image information transmitted from the video controller 102 is received and printing is performed. When the engine control unit 103 receives a print instruction from the video controller 102, the drive control unit 108 that controls driving of each unit of the image forming apparatus and the image forming unit 111 that forms an image based on the image data transmitted by the VIDEO signal 107. Then, an operation instruction is issued to each of the fixing control units 109 that control a fixing device that fixes the formed image on the recording material to control the image forming operation. State detection unit 110 is a sensor that detects the states of the respective units of the image forming apparatus, based on an input signal indicating the detection result of the state detection unit 110, the engine control unit 103 to detect the states of the respective units of the image forming apparatus Do.

  The video controller 102 can communicate with an externally connected PC 113, an operation panel 112 that performs various operations by a user, and displays a status of a laser beam printer, and an engine control unit 103. The SCLK signal 106 is a synchronous clock signal for communication between the video controller 102 and the engine control unit 103. The SC signal 105 is a data signal for transmitting and receiving data in synchronization with the SCLK signal 106. The / CCRT signal 104 is a state change notification signal for notifying the video controller 102 of the occurrence of a state change when the engine control unit 103 detects a state change of the image forming apparatus.

  FIG. 3 is a diagram illustrating a communication state between the engine control unit 103 and the video controller 102. A notification method for notifying the video controller 102 of a state change when the engine control unit 103 detects a state change in the image forming apparatus will be described. When the state detection unit 110 detects a change in the state of the image forming apparatus, the engine control unit 103 is notified. When the engine control unit 103 receives the state change information, the engine control unit 103 changes the status value according to the information. When the engine control unit 103 receives a change in the state of the image forming apparatus such as attachment / detachment of the paper feed cassette 301 or opening / closing of the door, the engine control unit 103 notifies the video controller 102 that the state change has occurred using the / CCRT signal 104. When the video controller 102 is notified of the occurrence of a change in the state of the image forming apparatus by the / CCRT signal 104, the video controller 102 requests the current status of the image forming apparatus from the engine control unit 103. Then, the engine control unit 103 is notified of the status changed in the image forming apparatus, and the status of the image forming apparatus in the video controller 102 is rewritten to information synchronized with the engine control unit 103. As described above, the video controller 102 and the engine control unit 103 transmit information from the engine control unit 103 to the video controller 102 when a state change occurs in the image forming apparatus in order to share the state of the image forming apparatus. .

  Next, a sheet cassette 301 will be described as an example of a specific status change of the image forming apparatus. FIG. 4 is a schematic configuration diagram of the paper feed cassette 301. When the paper feed cassette 301 is inserted into the image forming apparatus, the recording material size sensor 304 detects the insertion of the paper feed cassette 301. Simultaneously with the paper feed cassette insertion detection, the size of the recording material S loaded in the paper feed cassette 301 is detected from the combination of the outputs of the plurality of sensors of the recording material size sensor 304.

  When the recording material size sensor 304 determines that there is a paper feed cassette, the paper surface sensor 302 confirms whether the paper surface of the recording material S is detected. If there is no paper surface, the lifter motor 306 is driven to drive the cassette middle plate 305, and the recording material S is lifted up until it is detected by the paper surface sensor 302. When the recording material S is detected by the paper surface sensor 302, the recording material S is lifted up to a position where paper can be fed. When the recording material S is detected by the paper surface sensor 302 during the lift-up and the paper surface is present, the lift-up of the cassette intermediate plate 305 is finished and the detection value of the paper presence sensor 303 is confirmed. When a recording instruction is received from the video controller 102 in a state where the recording material S is detected by the paper presence sensor 303 and there is paper, the paper supply roller 307 is driven to feed the recording material S. Note that when the sheet cassette 301 is pulled out from the inserted state, the cassette intermediate plate 305 is lifted down. The engine control unit 103 holds, as the status of the paper feed cassette 301, a detection result of the presence or absence of the paper feed cassette, a detection result of the size of the recording material, and a detection result of the presence or absence of paper. When these statuses change, the engine control unit 103 notifies the video controller 102 that the status has changed. When the video controller 102 is notified that the status has changed, the video controller 102 acquires the changed status contents in order to update the changed status contents.

  FIG. 5 is a flowchart illustrating communication between the video controller 102 and the engine control unit 103 in the present embodiment. In step S <b> 501, the video controller 102 transmits a power saving mode shift instruction to the engine control unit 103 when an instruction from the user or a shift instruction to the power saving mode is generated by the real time clock of the video controller 102. When receiving an instruction to shift to the power saving mode from the video controller 102, in S502, the engine control unit 103 stores information of each sensor of the sheet feeding unit. In step S <b> 503, the engine control unit 103 sets a state change status, which is a status for storing a state change of the image forming apparatus that occurs during communication interruption with the video controller 102 in the power saving mode, to an initial value. In this embodiment, since the change in the sensor of the paper feed cassette 301 can be confirmed in the engine control unit 103 even in the power saving mode, the initial value of the state change status is assumed to be unchanged. In step S <b> 504, the engine control unit 103 performs processing for interrupting communication with the video controller 102. In step S505, the engine control unit 103 stops unnecessary power sources in the power saving mode and shifts to the power saving mode.

  In step S506, the engine control unit 103 determines whether there is a return instruction for returning from the power saving mode to the normal mode. A return instruction from the power saving mode is generated when the power switch is operated by the user. If there is no instruction to return from the power saving mode, in step S507, the engine control unit 103 compares the information of each sensor of the paper feeding unit held in S502 with the information of each sensor of the current paper feeding unit, and the paper feeding cassette 301. It is determined whether or not a state change has occurred. If a state change has occurred in the paper feed cassette 301, the engine control unit 103 changes the state change status from no change to change in S508. If no state change has occurred in the paper feed cassette 301, the process returns to S506.

  In S506, when the engine control unit 103 is instructed to return from the power saving mode, in S509, the engine control unit 103 is interrupted during the power-on process and the power saving mode in order to return from the power saving mode. The restart process of the state detection unit that has been performed is performed. Further, the drive control unit, the image forming unit, and the fixing control unit are returned to a state where image formation can be resumed. In S <b> 510, the engine control unit 103 performs communication resumption processing with the video controller 102. In S511, when communication is resumed, the video controller 102 checks whether there is a change in the state change status. If there is a change, in S512, the video controller 102 inquires of the engine control unit 103 what kind of change has occurred in the member that has changed. When the content of the change is received from the engine control unit 103, the status in the video controller 102 is updated, and the video controller 102 and the engine control unit 103 synchronize with respect to the state change of the image forming apparatus. On the other hand, when there is no state change, in S513, the video controller 102 and the engine control unit 103 enter a communication standby state.

  FIG. 6 is a time chart showing the communication state and status change between the video controller 102 and the engine control unit 103 in the present embodiment. Before and after the communication interruption, the cassette status indicates that the same cassette is present. Therefore, the video controller 102 cannot confirm the state of the paper feed cassette 301 during communication interruption simply by confirming the cassette status after returning from communication interruption. On the other hand, the status change status changes from no change to change due to the occurrence of a status change during communication interruption, that is, the paper feed cassette 301 is opened here. Even if the paper feed cassette 301 is closed again, the status change status remains unchanged, so the video controller 102 checks the status change status after returning from the communication interruption, so that a change occurs in the paper feed cassette 301 during the communication interruption. I understand that it was. Then, the video controller 102 and the engine control unit 103 can synchronize the state change that occurred during communication interruption by inquiring the engine control unit 103 about the specific content of the status change.

  As described above, the video controller 102 can recognize from the state change status that a status change has occurred while communication with the engine control unit 103 is interrupted. Therefore, after returning from the interruption of communication, the status change status can be confirmed by checking the status change status, so that even if the communication is interrupted, the change between the video controller 102 and the engine control unit 103 can be understood. You can share status changes. Further, by storing only the status of status change or no change as the status change status, it is possible to save memory compared to storing all history of status changes.

  In this embodiment, the target of the status change status has been described as the paper feed cassette 301. However, the present invention is not limited to the paper feed cassette 301. For example, the door opening / closing state of the image forming apparatus or the paper discharge unit The attachment / detachment state or the like may be targeted. The state change status notification method has been described as using a wired signal line, but is not limited to a wired signal line. For example, wireless communication or the like may be used. Although the communication means has been described as using clock synchronous communication, the communication means is not limited to clock synchronous communication, and for example, step synchronous communication may be used. In the present embodiment, an example in which the video controller 102 inquires of the engine control unit 103 about a specific status after notifying the state change status from the engine control unit 103 has been described. However, the present invention is not limited to this. For example, it is also possible to notify a specific status without notifying the video controller 102 after notifying the state change status from the engine control unit 103.

(Second Embodiment)
In the first embodiment, a state change in the image forming apparatus that occurs during communication interruption between the video controller 102 and the engine control unit 103 is stored as a state change status in two states: a change and no change. Explained when to do. However, when the occurrence of a state change during the power saving mode cannot be detected, there may be a case where the state change cannot be reliably identified before and after the communication is interrupted. Therefore, in the present embodiment, a case will be described in which the state change status during communication interruption is stored in three states: changed, unchanged, and indefinite. Note that the same reference numerals are given to the same configurations as those in the first embodiment, such as the configuration of the image forming apparatus, the communication method between the video controller 102 and the engine control unit 103, and the detailed description thereof is omitted here. To do.

  FIG. 7 is a flowchart illustrating communication between the video controller 102 and the engine control unit 103 in the present embodiment. In step S <b> 701, the video controller 102 transmits a power saving mode shift instruction to the engine control unit 103 when an instruction from the user or a shift instruction to the power saving mode is generated by the real time clock of the video controller 102. When the power saving mode transition instruction is received from the video controller 102, in S702, the engine control unit 103 stores information on each sensor of the sheet feeding unit. In step S <b> 703, the engine control unit 103 sets a status change status, which is a status for storing a status change of the image forming apparatus that occurs during communication interruption with the video controller 102 in the power saving mode, to an initial value. In this embodiment, since the change of the sensor of the paper feed cassette 301 cannot be confirmed in the power saving mode in the engine control unit 103, the initial value of the state change status is assumed to be unchanged or indefinite as shown in FIG. In step S <b> 704, the engine control unit 103 performs processing for interrupting communication with the video controller 102. In step S705, the engine control unit 103 stops unnecessary power sources in the power saving mode and shifts to the power saving mode.

In S706, the engine control unit 103 determines whether there is a return instruction for returning from the power saving mode to the normal mode. The engine control unit 103 monitors the return instruction until returning from the power saving mode that occurs when the power source SW is operated by the user. In S706, when the engine control unit 103 is instructed to return from the power saving mode, in S707, the engine control unit 103 is interrupted during the power-on process and the power saving mode in order to return from the power saving mode. The restart process of the state detection unit that has been performed is performed. Further, the image forming unit returns to a state where image formation of each part of the drive control unit, image forming unit, and fixing control unit can be resumed. In step S <b> 708, the engine control unit 103 compares the information of each sensor of the sheet feeding unit held in step S <b> 702 with the information of each sensor of the current sheet feeding unit, and determines whether or not a state change has occurred in the sheet feeding cassette 301. to decide. If a state change has occurred in the paper feed cassette 301, the engine control unit 103 changes the state change status from no change to change in S709. If no state change has occurred in the paper feed cassette 301, the state change status is not changed.

  In step S <b> 710, the engine control unit 103 performs communication resumption processing with the video controller 102. In step S <b> 711, the video controller 102 confirms whether there is a change in the state change status when communication is resumed. If there is a change, in S712, the video controller 102 inquires of the engine control unit 103 what kind of change has occurred in the member that has changed. When the content of the change is received from the engine control unit 103, the status in the video controller 102 is updated, and the video controller 102 and the engine control unit 103 synchronize with respect to the state change of the image forming apparatus. On the other hand, if there is no state change, the video controller 102 and the engine control unit 103 enter a communication standby state in S713. If the status change status is indefinite, a message is displayed on the operation panel 112 to prompt the user to specify the settings of the image forming apparatus again, or to operate in the status before the transition to the power saving mode. In step S713, the video controller 102 and the engine control unit 103 enter a communication standby state.

  FIG. 8 is a table showing initial values of the state change status when communication between the video controller 102 and the engine control unit 103 is interrupted. The initial value of the status change status when communication is interrupted depends on the state of the target sensor when communication is interrupted. For example, the state of the paper feed cassette 301 is determined by whether or not the paper feed cassette 301 is detected by the recording material size sensor 304. The paper surface detection state is determined by whether or not the paper surface is detected by the paper surface sensor 302. The paper presence / absence detection state is determined by whether or not the recording material is detected by the paper presence / absence sensor 303. Hereinafter, how to determine the initial value of the state change status will be described.

  Reference numeral 801 denotes a state without a cassette. In this case, the status change status can be determined only by the presence or absence of the cassette. The initial value of the status change status is assumed to be no change. Reference numeral 802 denotes a state before the lift-up is started. In this case, if the type of recording material is changed with the same paper size during communication interruption, the change of the recording material cannot be detected. Therefore, the initial value of the state change status is undefined. Reference numeral 803 denotes a state during lift-up. In this case, if the type of the recording material is changed with the same paper size during communication interruption as in the previous 802, the change of the recording material cannot be detected. Therefore, the initial value of the state change status is undefined. Reference numeral 804 denotes a state where the lift-up is completed and no cassette paper is confirmed. In this case, if the paper feed cassette 301 is opened while communication is interrupted, the middle plate falls and the paper surface sensor 302 does not output. Therefore, since the opening / closing detection of the sheet cassette 301 can be performed, the initial value of the state change status is assumed to be unchanged. Reference numeral 805 denotes a state in which the presence of paper is confirmed upon completion of lift-up. In this case, as in the case of the previous 804, if the paper feed cassette 301 is opened while communication is interrupted, the middle plate falls and the paper surface sensor 302 does not output. Therefore, since the opening / closing detection of the sheet cassette 301 can be performed, the initial value of the state change status is assumed to be unchanged.

  FIG. 9 is a time chart showing a communication state between the video controller 102 and the engine control unit 103 and a status change in the present embodiment. FIG. 9A shows a case where the initial value of the state change status does not change and the state change status can be determined after returning from communication interruption. FIG. 9B shows a case where the initial value of the state change status is indefinite and the state change status can be determined after returning from communication interruption. FIG. 9C shows a case where the initial value of the state change status is indefinite and the state change status cannot be determined after returning from communication interruption.

  In FIG. 9A, the cassette status indicates that the same cassette is present before and after the communication is interrupted. However, as described above with reference to 804 and 805, when the sheet cassette 301 is opened, the middle plate is displayed. Changes, it is possible to detect a change in state. Similarly to FIG. 9A, FIG. 9B can detect the state change because the middle plate falls when the paper feed cassette 301 is opened. On the other hand, FIG. 9C shows that the paper feed cassette 301 is opened while communication is interrupted. However, as described above with reference to 802 and 803, for example, during the lift-up of the paper feed cassette 301, the power saving mode is set. If the paper cassette 301 is opened in that state, a change in the state of the paper cassette 301 cannot be detected at the time of return, so the fact that the paper cassette 301 was opened during communication interruption is restored from the communication interruption. It cannot be detected later. Therefore, the status change status remains indefinite, and a message is displayed on the operation panel 112 to prompt the user to specify the settings of the image forming apparatus again, or to operate in a state before entering the power saving mode. And so on.

  As described above, the video controller 102 can recognize from the state change status that a status change has occurred while communication with the engine control unit 103 is interrupted. Therefore, by checking the status change status after returning from the communication interruption, the status change occurring in the image forming apparatus during the communication interruption can be understood. Even if the communication is interrupted, the video controller 102 and the engine control unit 103 The status change of status can be shared between users, and the user can be prompted to reset it.

  In this embodiment, the target of the status change status has been described as the paper feed cassette 301. However, the present invention is not limited to the paper feed cassette 301. For example, the door opening / closing state of the image forming apparatus or the paper discharge unit The attachment / detachment state or the like may be targeted. The state change status notification method has been described as using a wired signal line, but is not limited to a wired signal line. For example, wireless communication or the like may be used. Although the communication means has been described as using clock synchronous communication, the communication means is not limited to clock synchronous communication, and for example, step synchronous communication may be used. In the present embodiment, an example in which the video controller 102 inquires of the engine control unit 103 about a specific status after notifying the state change status from the engine control unit 103 has been described. However, the present invention is not limited to this. For example, it is also possible to notify a specific status without notifying the video controller 102 after notifying the state change status from the engine control unit 103.

(Third embodiment)
In the first embodiment, a state change in the image forming apparatus that occurs during communication interruption between the video controller 102 and the engine control unit 103 is stored as a state change status in two states: a change and no change. Explained when to do. In the second embodiment, the state change in the image forming apparatus that occurs during the interruption of communication between the video controller 102 and the engine control unit 103 is changed into three states: change, no change, and indefinite as the state change status. The case of memorizing was explained. However, the object to be detected by the status change status has been determined in advance. Thus, in the present embodiment, a case will be described in which a user can specify a target for detecting a state change status. Note that the same reference numerals are given to the same configurations as those in the first embodiment, such as the configuration of the image forming apparatus, the communication method between the video controller 102 and the engine control unit 103, and the detailed description thereof is omitted here. To do.

  FIG. 10 is a flowchart for explaining communication between the video controller 102 and the engine control unit 103 in the present embodiment. In the present embodiment, a member that detects a change in state during communication interruption is designated in advance from the video controller 102. In step S <b> 1001, the video controller 102 designates a member that detects a state change during communication interruption to the engine control unit 103. In step S <b> 1002, the video controller 102 transmits a power saving mode shift instruction to the engine control unit 103 when an instruction from the user or a shift instruction to the power saving mode is generated by the real time clock of the video controller 102. When the power saving mode shift instruction is received from the video controller 102, in S1003, the engine control unit 103 holds the current information of the member specified in S1001.

  In step S <b> 1004, the engine control unit 103 sets a state change status, which is a status for storing a state change of the image forming apparatus that occurs during communication interruption with the video controller 102 in the power saving mode, to an initial value. The initial value setting method is performed by the method described in S503 in the previous first embodiment or S703 in the previous second embodiment. In step S <b> 1005, the engine control unit 103 performs processing for interrupting communication with the video controller 102. In step S1006, the engine control unit 103 stops unnecessary power sources in the power saving mode and shifts to the power saving mode. The control after the power saving mode is performed by the method described in S506 to S513 in the first embodiment or S706 to S713 in the second embodiment.

  As described above, the video controller 102 can recognize that the status change has occurred while communication with the engine control unit 103 is interrupted, and further selects a target member to be detected based on the status change status. be able to. Thereby, it is possible to detect the state according to the user's intention.

  In the present embodiment, the state change status notification method has been described as using a wired signal line, but is not limited to a wired signal line, and wireless communication or the like may be used, for example. Although the communication means has been described as using clock synchronous communication, the communication means is not limited to clock synchronous communication, and for example, step synchronous communication may be used. In the present embodiment, an example in which the video controller 102 inquires of the engine control unit 103 about a specific status after notifying the state change status from the engine control unit 103 has been described. However, the present invention is not limited to this. For example, it is also possible to notify a specific status without notifying the video controller 102 after notifying the state change status from the engine control unit 103.

101 Laser beam printer 102 Video controller 103 Engine control unit

Claims (10)

Can communicate with the controller for controlling the image information for image forming, an image forming apparatus having an engine control unit which controls the images forming operation,
When communication with the controller and the engine controller is interrupted, the communication from the state before the communication is interrupted to detect that the state in which have been suspended was varied, that the state has changed comprising storage means for storing information indicating,
When the engine control unit returns from the interruption of communication with the controller, the engine control unit is stored in the storage unit without receiving a request for notification of the state change that occurred when the communication is interrupted from the controller . based on the information does not indicate the content of the state change of the image forming apparatus, image formation is characterized that you notice information on the status change of the image forming apparatus indicating whether or not a state change has occurred in the controller apparatus. When the controller is notified that a state change has occurred when communication is interrupted by information related to the state change of the image forming apparatus, the controller requests the engine control unit to notify the contents of the state change that has occurred. The image forming apparatus according to claim 1. When the engine control unit is requested by the controller to notify the content of the state change that occurred when communication is interrupted, the engine control unit detects the content of the state change in the image forming apparatus and notifies the controller. The image forming apparatus according to claim 2. When the engine control unit determines that there has been a state change based on the information stored in the storage unit, without receiving a request for notification of the content of the state change that occurred when communication was interrupted from the controller, The image forming apparatus according to claim 1 , wherein contents of a state change in the image forming apparatus are detected and notified to the controller. In a state where communication between the controller and the engine control unit is interrupted, communication interruption is continued even after information indicating that the state has changed is stored in the storage unit. Item 5. The image forming apparatus according to any one of Items 1 to 4. The controller and the communication with the engine control unit, an image forming apparatus according to any one of claims 1 to 5, characterized in that it is interrupted by becoming the power-saving mode. The storage unit, as information stored in said storage means, image according to any one of claims 1 to 6, characterized that you have a status of presence or absence of the state change is indeterminate can not be determined Forming equipment. An image forming apparatus capable of communicating with a first control means for controlling image information for image formation and having a second control means for controlling an image forming operation,
When the communication between the first control unit and the second control unit is interrupted, when detecting that the state when the communication is interrupted is changed from the state before the communication is interrupted, Storage means for storing information indicating that the state has changed,
When the second control unit recovers from the interruption of communication with the first control unit, the second control unit receives a request for notification of the content of the state change that occurred when the communication is interrupted from the first control unit. Instead, the information on the state change of the image forming apparatus indicating whether or not the state change has occurred is not shown based on the information stored in the storage means, but the contents of the state change of the image forming apparatus are not shown. An image forming apparatus that notifies the control means. An image forming apparatus capable of communicating with a controller for controlling image information for image formation and having an engine control unit for controlling an image forming operation,
If the engine control unit cannot determine the state change of the image forming apparatus when communication between the controller and the engine control unit is interrupted, information indicating that the state change is indefinite. Memorize it in the memory means,
An image forming apparatus, wherein when the communication with the controller is resumed, the controller is notified of information related to a state change of the image forming apparatus based on information stored in the storage unit. An image forming apparatus capable of communicating with a first control means for controlling image information for image formation and having a second control means for controlling an image forming operation,
If the second control unit cannot determine the state change of the image forming apparatus when communication between the first control unit and the second control unit is interrupted, the state change occurs. Information that indicates indefinite is stored in the storage means,
An image characterized in that when communication with the first control unit is resumed, the first control unit is notified of information relating to a state change of the image forming apparatus based on information stored in the storage unit. Forming equipment.

Images