Abstract: A reading apparatus includes: a conveyor that conveys transfer paper on which an image has been formed by using rotation of a stepping motor; a driver that performs control in such a manner as to supply control pulses to the stepping motor and rotate the stepping motor in predetermined target rotation steps; an encoder that detects the rotation of the stepping motor and obtains detected rotation steps; a reader that reads the image formed on the transfer paper in a state where the transfer paper is being conveyed by the conveyor; and a controller that detects a difference between an ideal value and an actual value of the detected rotation steps in the target rotation steps, and determines, on the basis of the difference, whether a read in the reader is valid or invalid.

Abstract: An image forming apparatus includes halogen lamp heaters, an AC power supply, a temperature detection unit and a control unit. The heaters have a same light distribution and heat a fixing member of an image fixing unit. The detection unit detects a temperature of the fixing member. The control unit determines a combination of the heaters based on output of the detection unit and applies a drive voltage of a half-wave of an AC waveform of the AC power supply to a heater of the heaters. The half-wave is selected based on an application pattern having a duty cycle of a predetermined value or more. The heaters include at least one heater which generates a heat amount being a minimum heat amount required for fixing or less when turned on with the application pattern having the duty cycle of the predetermined value.

Abstract: An image forming apparatus includes first and second heaters and a controller. The first and second heaters have a same light distribution and heat a roller of an image fixing unit. The second heater generates a less heat amount than the first heater. The controller applies a drive voltage to a heater of the heaters. When a heat amount generated by the second heater has increased to a first threshold value by the controller controlling the drive voltage, the controller switches the drive-voltage-applied heater from the second heater to the first heater. When a heat amount generated by the first heater has decreased to a second threshold value smaller than the first threshold value by the controller controlling the drive voltage, the controller switches the drive-voltage-applied heater from the first heater to the second heater.

Abstract: A reading apparatus includes: a conveyor that conveys transfer paper on which an image has been formed by using rotation of a stepping motor; a driver that performs control in such a manner as to supply control pulses to the stepping motor and rotate the stepping motor in predetermined target rotation steps; an encoder that detects the rotation of the stepping motor and obtains detected rotation steps; a reader that reads the image formed on the transfer paper in a state where the transfer paper is being conveyed by the conveyor; and a controller that detects a difference between an ideal value and an actual value of the detected rotation steps in the target rotation steps, and determines, on the basis of the difference, whether a read in the reader is valid or invalid.

Abstract: An image forming apparatus includes first and second heaters and a controller. The first and second heaters have a same light distribution and heat a roller of an image fixing unit. The second heater generates a less heat amount than the first heater. The controller applies a drive voltage to a heater of the heaters. When a heat amount generated by the second heater has increased to a first threshold value by the controller controlling the drive voltage, the controller switches the drive-voltage-applied heater from the second heater to the first heater. When a heat amount generated by the first heater has decreased to a second threshold value smaller than the first threshold value by the controller controlling the drive voltage, the controller switches the drive-voltage-applied heater from the first heater to the second heater.

Abstract: An image forming apparatus includes halogen lamp heaters, an AC power supply, a temperature detection unit and a control unit. The heaters have a same light distribution and heat a fixing member of an image fixing unit. The detection unit detects a temperature of the fixing member. The control unit determines a combination of the heaters based on output of the detection unit and applies a drive voltage of a half-wave of an AC waveform of the AC power supply to a heater of the heaters. The half-wave is selected based on an application pattern having a duty cycle of a predetermined value or more. The heaters include at least one heater which generates a heat amount being a minimum heat amount required for fixing or less when turned on with the application pattern having the duty cycle of the predetermined value.

Abstract: A sheet humidification apparatus includes a detect sensor that detects a position of a sheet which is being conveyed; a humidifier that changes a humidification amount and humidifies the sheet; and a controller that controls the humidifier such that a first region on a front end side of the sheet in a conveyance direction is humidified with a first humidification amount, and a second region of the sheet other than the first region is humidified with a second humidification amount larger than the first humidification amount in accordance with a position of the sheet detected by the detect sensor.

Abstract: A sheet humidification apparatus includes a detect sensor that detects a position of a sheet which is being conveyed; a humidifier that changes a humidification amount and humidifies the sheet; and a controller that controls the humidifier such that a first region on a front end side of the sheet in a conveyance direction is humidified with a first humidification amount, and a second region of the sheet other than the first region is humidified with a second humidification amount larger than the first humidification amount in accordance with a position of the sheet detected by the detect sensor.

Abstract: When an input image is to be formed on a sheet conveyed to a transfer roller, the exposure section is controlled and deviation correction is performed to offset the image forming position across the width of the sheet in response to the result of detection by a deviation sensor. By contrast, when pattern images are to be formed on a sheet in response to the instruction of the main control section, the image forming control section does not perform deviation correction in the process of forming a pattern image.

Abstract: An image formation control section sets a secondary transfer section in the pressed state in the case of execution of a main scanning correction processing as color registration correction, and sets the secondary transfer section in the separated state in the case of execution of a sub-scanning correction processing, an entire lateral magnification correction processing, a partial lateral magnification correction processing, or a skew correction processing, which is the correction of the image position for components other than the main scanning direction as color registration correction so as to prevent the situation where the correction accuracy of the image position with respect to the main scanning direction decreases and to prevent a decrease in print quality due to a residual image of a registration correction processing.

Abstract: A belt drive apparatus, including, an endless belt to be laid across in a tensioned condition between supporting rollers and to travel being in pressure contact with or being separated from a body to receive the pressure contact, a pressure contact/separating state detection section to detect whether the endless belt is in the pressure contact with the body or separated therefrom, a belt position detection section to detect a position of the endless belt in a width direction thereof, a belt abnormality judging section to judge whether the endless belt is in an abnormal position based on a detection result obtained by the belt position detection section and one of judgment values which are set correspondingly to the pressure contact/separating state of the endless belt, and a belt drive control section to control a drive of the endless belt.

Abstract: An image forming apparatus has an image forming section which transfers a toner image according to image data onto a recording sheet, a first fixing section which fixes the toner image with heat of the first fixing roller, a clear layer forming section which forms a clear layer on the toner image which the first fixing section has fixed, a second fixing section which fixes the clear layer with heat of the second fixing roller and a control section which controls the clear layer forming section to increase the thickness of the clear layer in a recording sheet area corresponding to a fixed area during the second revolution of the first fixing roller on the recording sheet, compared with a recording sheet area corresponding to a fixed area during the first revolution thereof.

Abstract: An image formation control section sets a secondary transfer section in the pressed state in the case of execution of a main scanning correction processing as color registration correction, and sets the secondary transfer section in the separated state in the case of execution of a sub-scanning correction processing, an entire lateral magnification correction processing, a partial lateral magnification correction processing, or a skew correction processing, which is the correction of the image position for components other than the main scanning direction as color registration correction so as to prevent the situation where the correction accuracy of the image position with respect to the main scanning direction decreases and to prevent a decrease in print quality due to a residual image of a registration correction processing.

Abstract: An image forming apparatus provided with an image forming section forming a reference mark at the position being away from the leading edge of the front surface of a sheet by a prescribed length, and forming an image for the front surface based on the forming position of the reference mark, a transfer sheet reversing section reversing the sheet, a leading edge detection sensor detecting the leading edge of the rear surface of the sheet and a mark detection sensor detecting the forming position of the reference mark on the sheet based on the leading edge of the rear surface of the transfer sheet, and the image forming section forms an image on the rear surface of the transfer sheet based on the forming position of the reference mark on the sheet whose reference point is the leading edge of the rear surface of the transfer sheet.

Abstract: An image forming apparatus for forming an image on a transfer sheet based on image data, comprises an operating section to determine a setup about a margin region on which an image is not formed at an edge portion of the transfer sheet, a control section to determine an inner region having a specified width and being adjacent to the determined margin region as a density change region in which an image density is changed, and determines a more inner region located inward more from the density change region as a regular density region in which an image is formed with a regular image density, and an image forming section to form an image in the density change region based on image data on the condition where the image density is reduced and to form an image in the regular density region based on image data without changing the image density.

Abstract: When an input image is to be formed on a sheet conveyed to a transfer roller, the exposure section is controlled and deviation correction is performed to offset the image forming position across the width of the sheet in response to the result of detection by a deviation sensor. By contrast, when pattern images are to be formed on a sheet in response to the instruction of the main control section, the image forming control section does not perform deviation correction in the process of forming a pattern image.

Abstract: Disclosed is a fixing device including a fixing belt to fix a toner image formed on a paper onto the paper, a driving unit to make the fixing belt reciprocate in a direction perpendicular to a feeding direction of the paper when fixing the toner image onto the paper and a detecting unit to detect a position of the fixing belt in the perpendicular direction, and a control target value of the fixing belt is changed in accordance with the position of the fixing belt in the perpendicular direction detected by the detecting unit, and the fixing belt is made to reciprocate by the driving unit based on the changed control target value.

Abstract: A belt drive apparatus, including, an endless belt to be laid across in a tensioned condition between supporting rollers and to travel being in pressure contact with or being separated from a body to receive the pressure contact, a pressure contact/separating state detection section to detect whether the endless belt is in the pressure contact with the body or separated therefrom, a belt position detection section to detect a position of the endless belt in a width direction thereof, a belt abnormality judging section to judge whether the endless belt is in an abnormal position based on a detection result obtained by the belt position detection section and one of judgment values which are set correspondingly to the pressure contact/separating state of the endless belt, and a belt drive control section to control a drive of the endless belt.

Abstract: While having an image forming section which transfers a toner image according to image data onto a recording sheet, a first fixing section which fixes the toner image on the recording sheet with heat of the first fixing roller which rotates on the recording sheet, a clear layer forming section which forms a clear layer on the toner image which the first fixing section has fixed, a second fixing section which fixes the clear layer on the recording sheet with heat of the second fixing roller which rotates on the recording sheet and a control section which controls each part, the control section controls the clear layer forming section to increase the thickness of the clear layer in the recording sheet area corresponding to the fixed area during the second revolution of the first fixing roller on the recording sheet, compared with the first revolution thereof.

Abstract: There is described a paper sheet conveyance apparatus, which makes it possible to surely separate the overlapping paper sheets from each other irrespective of a kind of paper. The apparatus includes: a thickness detecting section to detect a thickness of a paper sheet, currently conveyed in the conveyance path; a first suction device to adsorb the conveyance paper sheet currently passing through the first suction device; a second suction device to adsorb the overlap paper sheet currently passing through the second suction device; an overlapping conveyance path that is branched from the conveyance path; and a control section that activates the first suction device and the second suction device so as to separate the conveyance paper sheet from the overlap paper sheet, and to introduce the conveyance paper sheet and the overlap paper sheet into the conveyance path and the overlapping conveyance path, respectively.