Abstract: The image forming apparatus controls each laser scanner by setting the writing start timing in the sub-scanning direction to form the color registration correction image for correcting color registration at position according to the detection result of the image detection sensor. When forming the image on the sheet, the image forming apparatus sets the writing start timing in the sub-scanning direction according to the detection result of the image detection sensor and the amount of skew of the sheet to control each laser scanner. When forming the density detection toner image for correcting the density, the image forming apparatus sets the writing start timing in the sub-scanning direction to form the image at a position shifted by a pixel unit from the image forming position on the sheet.

Abstract: A detection unit detects a color registration pattern formed on a transfer member. A first correction unit detects an amount of color misregistration, relative to a forming position of a color pattern having a reference color, of a forming position of a color pattern having another color and determines an offset value for adjusting a write start timing of the other color. A measuring unit measures the inclination of the transfer member. A second correction unit determines, according to the inclination, an offset value for adjusting the write start timing of each of the plurality of image forming units and for adjusting, relative to the write start timing of a reference color, the write start timing of another color. The reference color for the first correction unit is different from the reference color for the second correction unit.

Abstract: An image forming apparatus determines a time length of a non-image-forming period in which image formation is not performed, the non-image-forming period being from when image formation on one recording sheet ends to when image formation on the next recording sheet starts, and based on the determined time length, decides the number of times of executing measurement (BD interval measurement) of a generation timing difference between detection signals corresponding to light beams emitted from two light emitting elements. The image forming apparatus executes the decided number of times of BD interval measurement and calculates an average value of the resultant measurement values.

Abstract: A detection unit detects a color registration pattern formed on a transfer member. A first correction unit detects an amount of color misregistration, relative to a forming position of a color pattern having a reference color, of a forming position of a color pattern having another color and determines an offset value for adjusting a write start timing of the other color. A measuring unit measures the inclination of the transfer member. A second correction unit determines, according to the inclination, an offset value for adjusting the write start timing of each of the plurality of image forming units and for adjusting, relative to the write start timing of a reference color, the write start timing of another color. The reference color for the first correction unit is different from the reference color for the second correction unit.

Abstract: The image forming apparatus controls each laser scanner by setting the writing start timing in the sub-scanning direction to form the color registration correction image for correcting color registration at position according to the detection result of the image detection sensor. When forming the image on the sheet, the image forming apparatus sets the writing start timing in the sub-scanning direction according to the detection result of the image detection sensor and the amount of skew of the sheet to control each laser scanner. When forming the density detection toner image for correcting the density, the image forming apparatus sets the writing start timing in the sub-scanning direction to form the image at a position shifted by a pixel unit from the image forming position on the sheet.

Abstract: An image forming apparatus determines a time length of a non-image-forming period in which image formation is not performed, the non-image-forming period being from when image formation on one recording sheet ends to when image formation on the next recording sheet starts, and based on the determined time length, decides the number of times of executing measurement (BD interval measurement) of a generation timing difference between detection signals corresponding to light beams emitted from two light emitting elements. The image forming apparatus executes the decided number of times of BD interval measurement and calculates an average value of the resultant measurement values.

Abstract: Provided is an electronic system capable of dynamically switching a communication speed among a plurality of electronic devices connected in series. A first communication device and a second communication device are connected in series to a host controller. After controlling the communication speed of the second communication device to be a communication speed defined in advance, the host controller controls the communication speed of the first communication device to be the same communication speed as the communication speed of the second communication device.

Abstract: Provided is an electronic device capable of performing stable communications between a plurality of electronic devices connected in series. A communication device (121) is inserted and connected to a serial communication channel between a host controller (101) and a communication device (141) at a subsequent stage, and includes a buffer (124) for temporarily accumulating a first data received from the communication device (141) at the subsequent stage. The communication device (121) monitors a communication situation with respect to the host controller (101) and the communication device (141), accumulates the first data in the buffer (124) when a second data to be transmitted from the communication device (121) to the host controller (101) is being transmitted to the host controller (101), and transmits the first data accumulated in the buffer (124) to the host controller (101) in response to the finish of transmission of the second data.

Abstract: An image forming apparatus connected to a conveying-speed-changeable sheet post processing device includes a discharging unit which discharges a sheet in a reverse discharge mode with front and back surfaces of the image-formed sheet reversed, and a non-reverse discharge mode without front and back surfaces of the image-formed sheet reversed, and discharges the sheet at a first speed or a second speed lower than the first speed; and a control unit which controls the discharging unit to discharge the sheet at the first speed in the reverse discharge mode and at the second speed in the non-reverse discharge mode. When the sheet is discharged at the second speed, the control unit controls the discharging unit to discharge a subsequent sheet at the second speed even if the subsequent sheet is to be discharged in the reverse discharge mode.

Abstract: Provided is an electronic system capable of dynamically switching a communication speed among a plurality of electronic devices connected in series. A first communication device and a second communication device are connected in series to a host controller. After controlling the communication speed of the second communication device to be a communication speed defined in advance, the host controller controls the communication speed of the first communication device to be the same communication speed as the communication speed of the second communication device.

Abstract: A sheet processing apparatus which is capable of improving operability while suppressing an increase in apparatus size. In a front cover insertion mode, an insertion sheet for a front cover is inserted into a bundle of sheets on which images have been formed, and in a rear cover insertion mode, an insertion sheet for a rear cover is inserted into the bundle of sheets. Insertion sheets for the front cover and insertion sheets for the rear cover are set with the same orientation in a manual feed tray 105. An insertion sheet for the front cover stored in the manual feed tray 105 is conveyed to a finisher 500 in one of a face-down state and a face-up state. An insertion sheet for the rear cover stored in the manual feed tray 105 is conveyed to the finisher 500 in the other of the face-down state and the face-up state. The insertion sheets for the front cover and for the rear cover conveyed from the manual feed tray 105 and the sheets on which images have been formed are stacked on the finisher 500.

Abstract: An image forming apparatus includes an image bearing member; toner image formation means for forming a toner image on the image bearing member; removing means for removing deposited matter deposited on the image bearing member; detecting means for detecting a toner image to be detected, formed on the toner image formation means; control means for controlling a toner image forming condition of the toner image forming means in accordance with a result of detection of the toner image to be detected by the detecting means; the apparatus being operable in a mode in which the removing means operates to remove the deposition, and the detecting means operates to detect the toner image to be detected, executing means for executing an operation in the mode; and an operating portion for manually starting execution of the operation in the mode by the executing means.

Abstract: An image-heating device has a detector for detecting the state of a recording medium at a position between a first fixing unit and a second fixing unit along a conveying path of the recording medium and a controller for controlling a fixing condition of the second fixing unit on the basis of the information obtained by the detector.

Abstract: There is provided an image forming apparatus that effectively suppresses an increase in temperature of a heating device by operating an air blowing device when image formation is performed to a small-size recording material, and which can continuously perform the image formation. The image forming apparatus includes a heating device to heat a recording material to be conveyed, a cooling fan that blows air from an air blowing port facing a part of the heating device, and a shutter that moves such that an opening width of the air blowing port is regulated depending on a width of the recording material. The image forming apparatus also includes an error detecting device that detects an error of the cooling fan. When the error detecting device detects an error of the cooling fan, the shutter moves to a position such that image formation is continued.

Abstract: An image forming apparatus capable of reducing a part of a sheet exposed outside the apparatus on standby after finishing printing a first side in both-sided printing. A transfer material P having an image formed on its first side is fed until a part thereof gets exposed outside a full-color printer 1 and is fed to a refeeding path in the full-color printer 1. The transfer material P inverted by a flapper 44 is fed to a standby position to form an image on a second side thereof and is stopped there. In the case where a preparation for forming the image on the second side is not completed, the standby position for having the transfer material P stopped is changed corresponding to length of the inverted transfer material P in a feeding direction.

Abstract: An image forming apparatus connected to a conveying-speed-changeable sheet post processing device includes a discharging unit which discharges a sheet in a reverse discharge mode with front and back surfaces of the image-formed sheet reversed, and a non-reverse discharge mode without front and back surfaces of the image-formed sheet reversed, and discharges the sheet at a first speed or a second speed lower than the first speed; and a control unit which controls the discharging unit to discharge the sheet at the first speed in the reverse discharge mode and at the second speed in the non-reverse discharge mode. When the sheet is discharged at the second speed, the control unit controls the discharging unit to discharge a subsequent sheet at the second speed even if the subsequent sheet is to be discharged in the reverse discharge mode.

Abstract: An image forming apparatus includes an image bearing member; toner image formation means for forming a toner image on the image bearing member; removing means for removing deposited matter deposited on the image bearing member; detecting means for detecting a toner image to be detected, formed on the toner image formation means; control means for controlling a toner image forming condition of the toner image forming means in accordance with a result of detection of the toner image to be detected by the detecting means; the apparatus being operable in a mode in which the removing means operates to remove the deposition, and the detecting means operates to detect the toner image to be detected, executing means for executing an operation in the mode; and an operating portion for manually starting execution of the operation in the mode by the executing means.

Abstract: An image forming apparatus includes an image bearing member; toner image formation means for forming a toner image on the image bearing member; removing means for removing deposited matter deposited on the image bearing member; detecting means for detecting a toner image to be detected, formed on the toner image formation means; control means for controlling a toner image forming condition of the toner image forming means in accordance with a result of detection of the toner image to be detected by the detecting means; the apparatus being operable in a mode in which the removing means operates to remove the deposition, and the detecting means operates to detect the toner image to be detected, executing means for executing an operation in the mode; and an operating portion for manually starting execution of the operation in the mode by the executing means.

Abstract: An image forming apparatus has an image forming device for forming a toner image on a recording material; a plurality of image heating devices for sequentially heating an image on the recording material in one of plural modes; a selecting device for selecting the mode and thus the number of the image heating devices to be used for heating the image; and a manual setting device for manually setting an operating condition of at least one of the image heating devices.

Abstract: An image forming apparatus includes a control unit for controlling a plurality of fixing units independently of one another regardless of a state of an image forming unit, and a receiving unit for receiving image forming requests, and has a control sequence, in which when not all of a recording medium material, a recording medium state, environment, and image data satisfy predetermined conditions, at least one of the plurality of fixing units are caused to operate, and a control sequence, in which when it is detected that an image forming request, for which all of the plurality of fixing units are required, is received by the receiving unit, each currently unused fixing unit is caused to operate. Accordingly, it is possible to realize high productivity even when there exist fixing units not driven due to the recording medium physical properties, recording medium state, environment, image data, or the like.