Abstract: Provided are a device and method for controlling a paper interval in a paper feeder of an image forming apparatus, and an image forming apparatus including the device. The device includes: a leading edge sensor configured to detect a leading edge of a sheet of paper when the sheet of paper is picked up and fed as a printing medium; a feed unit configured to accelerate the sheet of paper; and a control unit. If the sheet of paper arrives late at a paper sensing position of the leading edge sensor, the control unit measures a travel time during which the sheet of paper is fed to the paper sensing position, and according to the measured travel time, the control unit varies a time point at which the sheet of paper starts to be accelerated.

Abstract: Provided are a device and method for controlling a paper interval in a paper feeder of an image forming apparatus, and an image forming apparatus including the device. The device includes: a leading edge sensor configured to detect a leading edge of a sheet of paper when the sheet of paper is picked up and fed as a printing medium; a feed unit configured to accelerate the sheet of paper; and a control unit. If the sheet of paper arrives late at a paper sensing position of the leading edge sensor, the control unit measures a travel time during which the sheet of paper is fed to the paper sensing position, and according to the measured travel time, the control unit varies a time point at which the sheet of paper starts to be accelerated.

Abstract: A fitting structure for process cartridges and an image forming apparatus body of an image forming apparatus capable of fitting the process cartridges for plural colors thereto, the fitting structure including: an incompatible member with its cross-sectional shape in an axial direction being rotationally symmetrical, the incompatible member having at least one attaching projection and one displaying hole or one displaying notched portion formed on a position different from a rotational shaft of the rotationally symmetrical shape; an attached portion of the process cartridge capable of holding the incompatible member, having identification display portions for identifying the plural colors arranged on the position corresponding to the displaying hole or the displaying notched portion; and an acceptance portion of the image forming apparatus body having an acceptance concave portion for accepting the at least one attaching projection of the incompatible member.

Abstract: An image forming apparatus has a job-content recognition device for judging whether a number inputted as the number of print copies to be made is larger or smaller than a predetermined reference value; a print-data recognition device for judging whether or not inputted print data include image data and/or graphic data; and a control device for controlling executions of image stabilization control in a printing section. The control device sets a predetermined period as intervals among executions of the image stabilization control, and sets a period shorter than the predetermined period as the intervals among executions of the image stabilization control when the number inputted as the number of print copies to be made is larger than the predetermined reference value and also the inputted print data include image data and/or graphic data.

Abstract: A fitting structure for process cartridges and an image forming apparatus body of an image forming apparatus capable of fitting the process cartridges for plural colors thereto, the fitting structure including: an incompatible member with its cross-sectional shape in an axial direction being rotationally symmetrical, the incompatible member having at least one attaching projection and one displaying hole or one displaying notched portion formed on a position different from a rotational shaft of the rotationally symmetrical shape; an attached portion of the process cartridge capable of holding the incompatible member, having identification display portions for identifying the plural colors arranged on the position corresponding to the displaying hole or the displaying notched portion; and an acceptance portion of the image forming apparatus body having an acceptance concave portion for accepting the at least one attaching projection of the incompatible member.