Abstract: A control device includes a controller that determines, based on physical property information corresponding to physical property of a recording sheet and read information on an image evaluated as abnormal through reading of an image on the recording sheet by a reading section on a recording sheet conveyance path, a process condition under which an image forming section performs image forming on the recording sheet.

Abstract: A stacker device includes: a discharger that discharges sheets in response to a print job; a first tray on which the discharged sheets are stacked; a second tray that serves as a delivery destination of the sheets stacked on the first tray; a shutter that covers an opening on a front side of a housing; a driver that moves the first tray in an up-down direction; and a hardware processor that shuts off power to the driver based on a height position of the shutter and a position of the second tray in a front-rear direction.

Abstract: Provided is an image forming apparatus including an image carrier, a transfer unit, a driver, a hardware processor, an adjustment mechanism, and a speed detector. The hardware processor sets a command value. The hardware processor performs a constant-torque control based on a constant-speed drive torque detected in a constant-speed control. In the constant-torque control, the hardware processor performs a feedback control to set a reference value to an average speed of the driver during passage of a first sheet and calculate a difference from an average speed during passage of a subsequent sheet so as to derive the command value. The hardware processor determines whether a load torque increase, its factor, and/or its influence exceeds a threshold, and forcibly sets the reference value to a speed detected while a pressure between the transfer unit and the image carrier is reduced by the adjustment mechanism from the pressure during image transfer.

Abstract: The present invention provides a recording medium detecting device, an image forming device, an image forming system, a recording medium detecting method, and a non-transitory recording medium storing a computer readable program capable of detecting a grain direction of a recording medium. A recording medium detecting device has: a sensor capable of detecting a recording medium from a first detection direction and a second detection direction different from the first detection direction; and a control unit. The control unit determines a grain direction of a recording medium from first surface property data obtained when the recording medium is detected from the first detection direction and second surface property data obtained when the recording medium is detected from the second detection direction.

Abstract: Provided is an image forming apparatus including an image carrier, a transfer unit, a driver, a hardware processor, an adjustment mechanism, and a speed detector. The hardware processor sets a command value. The hardware processor performs a constant-torque control based on a constant-speed drive torque detected in a constant-speed control. In the constant-torque control, the hardware processor performs a feedback control to set a reference value to an average speed of the driver during passage of a first sheet and calculate a difference from an average speed during passage of a subsequent sheet so as to derive the command value. The hardware processor determines whether a load torque increase, its factor, and/or its influence exceeds a threshold, and forcibly sets the reference value to a speed detected while a pressure between the transfer unit and the image carrier is reduced by the adjustment mechanism from the pressure during image transfer.

Abstract: A stacker device includes: a discharger that discharges sheets in response to a print job; a first tray on which the discharged sheets are stacked; a second tray that serves as a delivery destination of the sheets stacked on the first tray; a shutter that covers an opening on a front side of a housing; a driver that moves the first tray in an up-down direction; and a hardware processor that shuts off power to the driver based on a height position of the shutter and a position of the second tray in a front-rear direction.

Abstract: An image forming system includes: an image forming apparatus that forms an image on a sheet; and a post-processor including a punch unit that forms a punch hole on the sheet conveyed from the image forming apparatus, wherein the image forming apparatus includes a conveyance control part that controls conveyance of the sheet to be conveyed to the post-processor, and the punch unit includes: a perforating part that forms the punch hole on the sheet; a detection part that performs sheet side end portion detection for detecting a side end portion in a main scanning direction, and paper dust detection for detecting a paper dust amount in a detection region; a swinging part that moves the perforating part to an arbitrary position; and a hardware processor that, when a punch job is performed, controls the detection part to perform the paper dust detection.

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 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.