Abstract: To prevent sheets from being allowed to be delivered after activation of a system when over-stacking has been detected before the activation of the system, a post-processing apparatus includes a stacking tray configured to allow sheets subjected to predetermined processing to be stacked thereon. The post-processing apparatus determines whether or not additional sheets are allowed to be stacked onto the stacking tray based on the number of sheets stacked on the stacking tray. The determination result indicating that the additional sheets are prohibited to be stacked onto the stacking tray is stored in a nonvolatile RAM. The post-processing apparatus determines, after being activated, whether or not the determination result is stored in the nonvolatile RAM, and determines that the additional sheets are prohibited to be stacked onto the stacking tray when the determination result is stored in the nonvolatile RAM.

Abstract: An image forming apparatus includes an image forming unit to form an image on a sheet, an intermediate processing tray where sheets conveyed through a first conveyance path are stacked as a sheet bundle, a sensor disposed at a second conveyance path to detect a conveyed sheet bundle, and a stacking tray in which sheets discharged through a discharging path diverging from the first conveyance path are stacked. In response to a sensor detected paper jam, a control unit determines the intermediate processing tray as the discharging destination for a sheet among the remaining sheets, and determines the stacking tray as the discharging destination for a sheet among the remaining sheets. After the paper jam is cleared, the control unit causes execution of bookbinding and cutting for a sheet bundle including the remaining sheets stacked in the intermediate processing tray.

Abstract: A sheet processing apparatus that is capable of facilitating a process by eliminating waste of a result even if a translucent sheet is conveyed. A conveyance unit conveys a sheet received from an image forming apparatus. An optical sensor detects a sheet end conveyed. An alignment unit aligns sheets based on information detected by the optical sensor. A post-process unit performs a post-process to the sheets aligned. An input unit inputs sheet information about a type of the sheet to be received from the image forming apparatus. A control unit stops sheet conveyance when the sheet information indicates a first type sheet and when the optical sensor cannot detect the sheet end, and continues sheet conveyance when the sheet information indicates a second type sheet of which transmittance is higher than the first type sheet and when the optical sensor cannot detect the sheet end.

Abstract: A sheet processing apparatus capable of discharging even a lateral displacement uncorrectable sheet onto a discharge tray without collision with an alignment plate. A finisher conveys a sheet along a conveying path. A shift unit corrects a lateral displacement of the sheet based on a result of detection by a lateral displacement detection sensor. Sheets discharged via the conveying path are stacked on a discharge tray. A pair of alignment plates disposed above the stacking tray are lowered and are moved between a standby position and an alignment position to be brought into abutment with respective opposite edges of the discharged sheet in the alignment position. A finisher controller makes a distance between the alignment plates in a standby position different according to a sheet type, even when a size of the sheet in the width direction is the same.

Abstract: A sheet conveying apparatus that restricts conveyance of sheets to a post-processing apparatus which has become incapable of continuing a post-processing operation. The sheet conveying apparatus is communicably connected to the post-processing apparatus that performs post-processing on a sheet bundle formed by sheets. The sheet conveying apparatus includes a conveying unit for conveying sheets and an escape tray for receiving conveyed sheets which are not conveyed to the post-processing apparatus. A value corresponding to the number of sheet bundles formed by conveyed sheets is counted. A CPU circuit section determines based on communication with the post-processing apparatus whether or not the post-processing operation can be continued thereby. When it is determined that the post-processing operation cannot be continued, the CPU circuit section switches the sheet conveying destination from the post-processing apparatus to the escape tray, based on the counted value.

Abstract: A sheet processing apparatus capable of properly stacking sheets by detecting abnormality of a sheet stacking state during a sheet stacking operation to thereby prevent stack overflow. In the sheet processing apparatus, a conveyed sheet is stacked on a stacking tray. A sheet presence sensor detects a sheet on a sheet stacking surface of the stacking tray. A sheet height reduction sensor detects sheets within a predetermined distance downward from the uppermost surface of sheets stacked on the stacking tray. When the sheet presence sensor detects no sheet, and the sheet height reduction sensor detects a sheet during an operation for discharging a plurality of sheets onto the stacking tray, it is determined that an abnormal stacking state has occurred, and conveyance of a sheet is stopped.

Abstract: A sheet processing apparatus capable of properly stacking sheets by detecting abnormality of a sheet stacking state during a sheet stacking operation to thereby prevent stack overflow. In the sheet processing apparatus, a conveyed sheet is stacked on a stacking tray. A sheet presence sensor detects a sheet on a sheet stacking surface of the stacking tray. A sheet height reduction sensor detects sheets within a predetermined distance downward from the uppermost surface of sheets stacked on the stacking tray. When the sheet presence sensor detects no sheet, and the sheet height reduction sensor detects a sheet during an operation for discharging a plurality of sheets onto the stacking tray, it is determined that an abnormal stacking state has occurred, and conveyance of a sheet is stopped.

Abstract: Provided is a puncher having activating/inactivating switch for post-processing function. The puncher prevents undesirable post processing even if the switch indicates activation of the post processing. When a puncher which is registered in the image forming apparatus is attached to the puncher, the puncher obtains information indicating whether or not to the post processing using a punch die is activated or not. When the obtained information indicates that the post processing using the punch die is inactivated, even if the switch indicates activation of the post processing, the post processing is not performed.

Abstract: To prevent sheets from being allowed to be delivered after activation of a system when over-stacking has been detected before the activation of the system, a post-processing apparatus includes a stacking tray configured to allow sheets subjected to predetermined processing to be stacked thereon. The post-processing apparatus determines whether or not additional sheets are allowed to be stacked onto the stacking tray based on the number of sheets stacked on the stacking tray. The determination result indicating that the additional sheets are prohibited to be stacked onto the stacking tray is stored in a nonvolatile RAM. The post-processing apparatus determines, after being activated, whether or not the determination result is stored in the nonvolatile RAM, and determines that the additional sheets are prohibited to be stacked onto the stacking tray when the determination result is stored in the nonvolatile RAM.

Abstract: An image forming apparatus includes an image fixing portion detachably mountable to a main assembly and including first and second rollers forming an image fixing nip therebetween; a rubbing roller for rubbing treatment of the first roller; a setting portion for setting whether to permit the execution of the treatment when a number of the recording materials fed to the fixing portion exceeds a predetermined number; a storing portion, provided in the fixing portion, for storing set information corresponding to the setting relating to permission of the treatment set through the setting portion; and a controller for controlling execution of the treatment. If the set information in the storing portion indicates the permission of the treatment, the controller executes the treatment. If not, the controller does not execute the treatment.

Abstract: A sheet processing apparatus that is capable of facilitating a process by eliminating waste of a result even if a translucent sheet is conveyed. A conveyance unit conveys a sheet received from an image forming apparatus. An optical sensor detects a sheet end conveyed. An alignment unit aligns sheets based on information detected by the optical sensor. A post-process unit performs a post-process to the sheets aligned. An input unit inputs sheet information about a type of the sheet to be received from the image forming apparatus. A control unit stops sheet conveyance when the sheet information indicates a first type sheet and when the optical sensor cannot detect the sheet end, and continues sheet conveyance when the sheet information indicates a second type sheet of which transmittance is higher than the first type sheet and when the optical sensor cannot detect the sheet end.

Abstract: A sheet stacking apparatus for performing post-processing on sheets received from an image forming apparatus and discharging the processed sheets. A stacking tray has the received sheets stacked thereon. A CPU controls a tray lifting/lowering motor to drive the stacking tray to be lifted or lowered. The CPU determines a vertically moving state of the stacking tray. When the stacking tray is not lowered though the tray lifting/lowering motor is controlled to lower the stacking tray, the CPU notifies the image forming apparatus that a job should be suspended. After notifying, the CPU controls the tray lifting/lowering motor to lift the stacking tray. Then, when the stacking tray can be lifted, the CPU notifies the image forming apparatus that the job is to be resumed.

Abstract: An image forming system which can recognize the network configuration in real time is provided. The image forming system comprises an image forming apparatus for performing image formation and one or more accessory devices capable of establishing communication with the image forming apparatus via network bus. The image forming apparatus stores identification information which identifies each of the one or more accessory devices. The accessory device detects a communication state of the network bus to notify the image forming apparatus or accessory device which is adjacent of occurrence of communication error not via the network bus. When the occurrence of the communication error of the network bus is notified from the accessory device which is adjacent, the image forming apparatus realizes the network configuration in real time and erases the identification information stored.

Abstract: A sheet processing apparatus capable of discharging even a lateral displacement uncorrectable sheet onto a discharge tray without collision with an alignment plate. A finisher conveys a sheet along a conveying path. A shift unit corrects a lateral displacement of the sheet based on a result of detection by a lateral displacement detection sensor. Sheets discharged via the conveying path are stacked on a discharge tray. A pair of alignment plates disposed above the stacking tray are lowered and are moved between a standby position and an alignment position to be brought into abutment with respective opposite edges of the discharged sheet in the alignment position. A finisher controller makes a distance between the alignment plates in a standby position different according to a sheet type, even when a size of the sheet in the width direction is the same.

Abstract: An apparatus includes a movable regulation member that regulates a trailing edge side position of a sheet stack stored in a storage portion in a sheet feeding direction, a trailing edge detection portion, movable together with the regulation member, that detects a sheet surface on the trailing edge side of the sheet stack, and a control unit that detects whether the regulation member is positioned to an end surface on the trailing edge side of the sheet stack based on a detection result by the trailing edge detection portion, and that causes a display unit to provide a warning if the regulation member is not positioned to the end surface, wherein, if a predetermined sheet with thicknesses different between leading edge and trailing edge sides thereof in the sheet feeding direction is set by a setting unit, the control unit does not cause the display unit to provide the warning.

Abstract: A sheet feeding apparatus includes a containing unit, a lifting and lowering unit, a loosening unit, a feed unit, a sheet-surface detection unit, an aligning member, a trailing-edge detection unit, a double-feed detection unit, and a control unit. Sheets, of a sheet bundle contained in the containing unit and lifted and lowered, are loosened by blowing air into the sheet bundle and fed. An end face of the contained sheet bundle is aligned on a trailing-edge side. The trailing-edge detection unit moves with the aligning member and detects a sheet surface of a top of the sheet bundle on the trailing-edge side. Where double feed from the containing unit is detected, a detection operation detects, in consideration of a trailing-edge detection unit result, whether the aligning member is located at a position at which the end face of the sheet bundle on the trailing-edge side is aligned.

Abstract: The image forming system comprises an accessory device and an image forming apparatus, the accessory device for storing device identification information for identifying its own device, and the image forming apparatus to which the accessory device is connected. The image forming apparatus stores the device identification information of the accessory device included in the image forming system. Further, the image forming apparatus receives a participation notification which requires participating in the image forming system from a new accessory device including the device identification information. If the device identification information included in the received participation notification is not stored, the image forming apparatus stores the information. If already stored, the image forming apparatus discards the participation notification.

Abstract: An image forming system which can recognize the network configuration in real time is provided. The image forming system comprises an image forming apparatus for performing image formation and one or more accessory devices capable of establishing communication with the image forming apparatus via network bus. The image forming apparatus stores identification information which identifies each of the one or more accessory devices. The accessory device detects a communication state of the network bus to notify the image forming apparatus or accessory device which is adjacent of occurrence of communication error not via the network bus. When the occurrence of the communication error of the network bus is notified from the accessory device which is adjacent, the image forming apparatus realizes the network configuration in real time and erases the identification information stored.

Abstract: A sheet stacking apparatus for performing post-processing on sheets received from an image forming apparatus and discharging the processed sheets. A stacking tray has the received sheets stacked thereon. A CPU controls a tray lifting/lowering motor to drive the stacking tray to be lifted or lowered. The CPU determines a vertically moving state of the stacking tray. When the stacking tray is not lowered though the tray lifting/lowering motor is controlled to lower the stacking tray, the CPU notifies the image forming apparatus that a job should be suspended. After notifying, the CPU controls the tray lifting/lowering motor to lift the stacking tray. Then, when the stacking tray can be lifted, the CPU notifies the image forming apparatus that the job is to be resumed.

Abstract: A sheet conveying apparatus that restricts conveyance of sheets to a post-processing apparatus which has become incapable of continuing a post-processing operation. The sheet conveying apparatus is communicably connected to the post-processing apparatus that performs post-processing on a sheet bundle formed by sheets. The sheet conveying apparatus includes a conveying unit for conveying sheets and an escape tray for receiving conveyed sheets which are not conveyed to the post-processing apparatus. A value corresponding to the number of sheet bundles formed by conveyed sheets is counted. A CPU circuit section determines based on communication with the post-processing apparatus whether or not the post-processing operation can be continued thereby. When it is determined that the post-processing operation cannot be continued, the CPU circuit section switches the sheet conveying destination from the post-processing apparatus to the escape tray, based on the counted value.