Abstract: An image forming system includes an image forming unit configured to form a toner image on a recording material; a fixing device configured to fix the toner image on the recording material on which the toner image is formed by the image forming unit; a first cooling unit capable of cooling the recording material passing through the fixing device; a second cooling unit capable of cooling the recording material passing through the first cooling unit; and a control unit configured to carry out control so that during execution of an image forming job, the image forming job is stopped when both the first cooling unit and the second cooling unit are out of order and is continued when only one of the first cooling unit and the second cooling unit is out of order.

Abstract: An electric wire bundle in which a plurality of electric wires are bundled without using a wire bundling tool is provided. The electric wire bundle, formed by bundling a plurality of the electric wires, connects devices. The electric wire connecting two devices positioned farthest from each other is wound by the other electric wire. Other electric wires branch in order at branch points provided between the two devices positioned farthest from each other and are connected to a corresponding device.

Abstract: An image forming system includes an image forming unit configured to form a toner image on a recording material; a fixing device configured to fix the toner image on the recording material on which the toner image is formed by the image forming unit; a first cooling unit capable of cooling the recording material passed through the fixing device; a second cooling unit capable of cooling the recording material passed through the first cooling unit; and a control unit configured to carry out control so that during execution of an image forming job, the image forming job is stopped when both the first cooling unit and the second cooling unit are out of order and is continued when either one of the first cooling unit and the second cooling unit is out of order.

Abstract: A sheet feeding device comprises sheet storage for storing a sheet, a merging conveying unit for feeding the sheet from the sheet storage to an image forming apparatus, a transmitting element for transmitting an ultrasonic signal to the sheet conveyed on the merging conveying unit, and a receiving element for receiving the ultrasonic signal having passed through the sheet and outputting an output signal according to strength of the received ultrasonic signal. When the sheet is a Japanese paper, the sheet feeding device detects double feeding of the sheet according to an average value of a plurality of the output signals and variation in a plurality of the output signals obtained for the one sheet. If the sheet is not double fed, the sheet is fed to the image forming apparatus. If the sheet is double fed, the sheet is discharged to the escape tray.

Abstract: An electric wire bundle in which a plurality of electric wires are bundled without using a wire bundling tool is provided. The electric wire bundle, formed by bundling a plurality of the electric wires, connects devices. The electric wire connecting two devices positioned farthest from each other is wound by the other electric wire. Other electric wires branch in order at branch points provided between the two devices positioned farthest from each other and are connected to a corresponding device.

Abstract: A sheet feeding device comprises sheet storage for storing a sheet, a merging conveying unit for feeding the sheet from the sheet storage to an image forming apparatus, a transmitting element for transmitting an ultrasonic signal to the sheet conveyed on the merging conveying unit, and a receiving element for receiving the ultrasonic signal having passed through the sheet and outputting an output signal according to strength of the received ultrasonic signal. When the sheet is a Japanese paper, the sheet feeding device detects double feeding of the sheet according to an average value of a plurality of the output signals and variation in a plurality of the output signals obtained for the one sheet. If the sheet is not double fed, the sheet is fed to the image forming apparatus. If the sheet is double fed, the sheet is discharged to the escape tray.

Abstract: A sheet conveyance apparatus including a transmission unit that transmits an ultrasonic wave toward a sheet and a reception unit that receives the ultrasonic wave includes a change unit that changes a distance of a conveyance path of the sheet according to sheet information about the sheet to be conveyed.

Abstract: A sheet processing apparatus includes a binding unit configured to perform binding processing by pressing a sheet bundle, a motor configured to drive the binding unit to press the sheet bundle, and a motor control unit configured to set a driving current of the motor and an upper limit value of the driving current, the motor control unit being configured to set the driving current when starting activating the motor in a state where the binding unit is not pressing the sheet bundle to a first value, and set the upper limit value of the driving current in a period in which the binding unit is pressing the sheet bundle to a second value less than or equal to the first value.

Abstract: A sheet conveyance apparatus including a transmission unit that transmits an ultrasonic wave toward a sheet and a reception unit that receives the ultrasonic wave includes a change unit that changes a distance of a conveyance path of the sheet according to sheet information about the sheet to be conveyed.

Abstract: An image forming apparatus that reduces density irregularity caused by SD gap variation. A developing bias voltage for forming a developing electric field between a photosensitive drum and a developing sleeve is applied to the developing sleeve. A rotational period of the photosensitive drum is divided into a plurality of blocks, and current values are acquired for each block. An average value of the acquired current values for each block is stored until the photosensitive drum is rotated a predetermined number of times, for each of the predetermined number of times of rotation. A moving average value of the average values in each block is calculated, and a correction table for correcting the developing bias voltage to be applied in each block is created using the calculated moving average values, and the developing bias voltage is controlled based on the created correction table.

Abstract: A sheet processing apparatus includes a binding unit configured to perform binding processing by pressing a sheet bundle, a motor configured to drive the binding unit to press the sheet bundle, and a motor control unit configured to set a driving current of the motor and an upper limit value of the driving current, the motor control unit being configured to set the driving current when starting activating the motor in a state where the binding unit is not pressing the sheet bundle to a first value, and set the upper limit value of the driving current in a period in which the binding unit is pressing the sheet bundle to a second value less than or equal to the first value.

Abstract: An image forming apparatus that reduces density irregularity caused by SD gap variation. A developing bias voltage for forming a developing electric field between a photosensitive drum and a developing sleeve is applied to the developing sleeve. Current values of an AC component of the developing bias voltage are detected while changing the acquisition timing for each rotation of the photosensitive drum, and detected current values are interpolated and averaged at each same phase with reference to the time of detection by the drum home position sensor HP. From the averaged current values of the variation curves of the developing bias AC current over the plurality of rotations, a correction table for an output control signal of the developing bias voltage is created. The developing bias voltage is controlled based on the created correction table.

Abstract: Provided are a sheet feeding device and an image forming apparatus that are capable of accurately detecting an abnormality of a feeding state without erroneously detecting when a trailing edge of a preceding sheet and a leading edge of a subsequent sheet are fed in an overlaid state. The sheet feeding device includes ultrasonic wave sensors 6 and 7 that detect an overlaid state of a preceding sheet Sa and a subsequent sheet Sb fed from feeding portions 51, 317 to 319 and a controller 1 that continuously performs a detection of the overlaid state of a sheet fed from the feeding portion at a predetermined number of detecting points along a sheet conveying direction at every predetermined time and determines a number of detecting points where detects. Based on the determined number of detecting points, the controller determines that the overlaid state is normal or abnormal.

Abstract: An image forming apparatus that reduces density irregularity caused by SD gap variation. A developing bias voltage for forming a developing electric field between a photosensitive drum and a developing sleeve is applied to the developing sleeve. A rotational period of the photosensitive drum is divided into a plurality of blocks, and current values are acquired for each block. An average value of the acquired current values for each block is stored until the photosensitive drum is rotated a predetermined number of times, for each of the predetermined number of times of rotation. A moving average value of the average values in each block is calculated, and a correction table for correcting the developing bias voltage to be applied in each block is created using the calculated moving average values, and the developing bias voltage is controlled based on the created correction table.

Abstract: An image forming apparatus that reduces density irregularity caused by SD gap variation. A developing bias voltage for forming a developing electric field between a photosensitive drum and a developing sleeve is applied to the developing sleeve. Current values of an AC component of the developing bias voltage are detected while changing the acquisition timing for each rotation of the photosensitive drum, and detected current values are interpolated and averaged at each same phase with reference to the time of detection by the drum home position sensor HP. From the averaged current values of the variation curves of the developing bias AC current over the plurality of rotations, a correction table for an output control signal of the developing bias voltage is created. The developing bias voltage is controlled based on the created correction table.

Abstract: A sheet feeder which is capable of accurately detecting multi-feed of sheets even when the distance between sensors is changed. The sheet feeder includes a sheet container for holding a stack of sheets. Ultrasonic sensors for transmitting and receiving ultrasonic waves, respectively, are provided on a conveying path. The ultrasonic sensor as a transmitter transmits ultrasonic waves to a sheet being fed and conveyed. A reception circuit detects a level of ultrasonic waves received by the ultrasonic sensor as a receiver. The level of ultrasonic waves detected after lapse of a predetermined time from transmission of ultrasonic waves is compared with a predetermined threshold value to determine multi-feed of sheets. A distance between the ultrasonic sensors is detected, and at least one of the predetermined time period and the predetermined threshold value is corrected based on the detected distance between the sensors.

Abstract: Provided is a sheet feeding apparatus capable of reliably feeding thin sheets in a separated state and an image forming apparatus including the same. A floating preventing member which regulates an upward movement of an uppermost sheet floated by air is provided so as to be lifted and lowered between a tail end regulating plate regulating the position of the sheet above a tray and an adsorbing and conveying portion which conveys the uppermost sheet floated by the air blowing from a downstream air blowing portion. The adsorbing and conveying portion is moved to a predetermined regulating position higher than the height position of the uppermost sheet and lower than the feeding surface of the adsorbing and conveying portion before the sheet is floated, which suppresses the movement of the sheet toward the tail end side caused by the curling of the sheet due to the air.

Abstract: Provided are a high-quality sheet feeding apparatus which can detect multifeeding of sheets in a wide range of the sheet conveying direction and realize a stable conveying state, and an image forming apparatus therewith. A CPU controls a multifeeding detection sensor to detect multifeeding of sheets at a plurality of transmission points P1 to P5 of the multifeeding detection sensor. This CPU sets a plurality of transmission points across the front end and rear end of a sheet moving in the sheet conveying direction, based on size information of the sheet read from a storage portion and the timing of detection passing of the sheet in a horizontal path first sensor. This enables detection of multifeeding across the front end and rear end of a preceding sheet in the sheet conveying direction, and also enables detection of unseparated multifeeding that a subsequent sheet follows overlapping the preceding sheet.

Abstract: A sheet feeder which is capable of accurately detecting multi-feed of sheets even when the distance between sensors is changed. The sheet feeder includes a sheet container for holding a stack of sheets. Ultrasonic sensors for transmitting and receiving ultrasonic waves, respectively, are provided on a conveying path. The ultrasonic sensor as a transmitter transmits ultrasonic waves to a sheet being fed and conveyed. A reception circuit detects a level of ultrasonic waves received by the ultrasonic sensor as a receiver. The level of ultrasonic waves detected after lapse of a predetermined time from transmission of ultrasonic waves is compared with a predetermined threshold value to determine multi-feed of sheets. A distance between the ultrasonic sensors is detected, and at least one of the predetermined time period and the predetermined threshold value is corrected based on the detected distance between the sensors.

Abstract: A sheet feeding device includes drawing and conveying a sheet, applying negative pressure for sheet suction via a suction opening, moving a shutter member between a closing position where the suction opening in an upstream side in a sheet feeding direction is partially closed and an open position where the suction opening is opened, and controlling the shutter member to follow a preceding sheet that is drawn onto the suction conveyance member to move to the downstream side in the feeding direction to close the suction opening, and return to an open position at a predetermined timing to draw the sheets onto the suction conveyance member in a state where an upstream edge of the preceding sheet in the feeding direction and a downstream edge of the subsequent sheet in the feeding direction are overlaid by a predetermined amount.