摘要:
A developing device includes a developing roller and a blade. The developing roller includes: a developing sleeve which rotates while holding two-component developer composed of toner and magnetic carrier on the outer surface having a plurality of grooves extending in parallel to an axis of the rotation; and a magnetic member, provided inside the developing sleeve in such a manner as to be unrotatable, for attracting the two-component developer onto the outer surface of the developing sleeve. The blade is provided outside the rotating sleeve with a gap from the outer surface of the developing sleeve for scraping off a part of the two-component developer on the outer surface of the developing sleeve. Also, the magnetic member includes a magnet for controlling magnetic flux density in the gap to range from 70 mT to 150 mT. This allows preventing image degradation caused by generation of development memory.
摘要:
The change in an output voltage when a control voltage is changed is calculated, and the change in the control voltage divided by the calculated change in the output voltage is defined as a sensitivity coefficient. The sensitivity coefficient is recalculated for each predetermined time interval or whenever a predetermined condition is satisfied, and the control voltage is corrected based on the recalculated sensitivity coefficient. Example of the predetermined condition include the time of start-up of the apparatus, the time at which the accumulated number of printed sheets reaches a predetermined number, and the time of carrying out process control.
摘要:
A developing device includes a developing roller and a blade. The developing roller includes: a developing sleeve which rotates while holding two-component developer composed of toner and magnetic carrier on the outer surface having a plurality of grooves extending in parallel to an axis of the rotation; and a magnetic member, provided inside the developing sleeve in such a manner as to be unrotatable, for attracting the two-component developer onto the outer surface of the developing sleeve. The blade is provided outside the rotating sleeve with a gap from the outer surface of the developing sleeve for scraping off a part of the two-component developer on the outer surface of the developing sleeve. Also, the magnetic member includes a magnet for controlling magnetic flux density in the gap to range from 70 mT to 150 mT. This allows preventing image degradation caused by generation of development memory.
摘要:
An image forming apparatus that includes: an image forming portion for forming an image in accordance with image data contained in an input command; and a controller for controlling the image forming portion, and is constructed such that the controller includes: a mode switch for switching the image forming portion from a standby mode in which image forming is instantly enabled into a power-saving mode in which power supply to the image forming portion is partially stopped when no subsequent command has been received after a predetermined period elapsed from when image forming portion was operated last; a mode restoring portion for restoring the image forming portion from power-saving mode to standby mode when a subsequent command is received; and an image quality controller for performing image quality control of the image every time a predetermined time elapsed from when the image forming portion was last operated, and the image quality controller starts execution of the image quality control before the mode restoring portion restores the image forming portion from the power-saving mode to the standby mode.
摘要:
The change in an output voltage when a control voltage is changed is calculated, and the change in the control voltage divided by the calculated change in the output voltage is defined as a sensitivity coefficient. The sensitivity coefficient is recalculated for each predetermined time interval or whenever a predetermined condition is satisfied, and the control voltage is corrected based on the recalculated sensitivity coefficient. Example of the predetermined condition include the time of start-up of the apparatus, the time at which the accumulated number of printed sheets reaches a predetermined number, and the time of carrying out process control.
摘要:
An image forming apparatus capable of performing monochrome printing and color printing in which all the developing units share a single development transformer is constructed such that at the time of monochrome printing the photoreceptor drums for colors are stopped rotating while all the developing units are constantly applied with a high voltage. Further, the cumulative operation time in which the black photoreceptor drum has been operated for monochrome printing is calculated so that the color-printing photoreceptor drums which are stopped during monochrome printing are rotationally driven by a predetermined angle when the cumulative operation time exceeds predetermined fixed time. Thus, the surface of each color-printing photoreceptor drum that is being worn is restored by making the fresh surface of the drum oppose the associated color developing unit, whereby it is possible to prevent occurrence of defects on the surface of each photoreceptor drum.
摘要:
An image forming apparatus that includes: an image forming portion for forming an image in accordance with image data contained in an input command; and a controller for controlling the image forming portion, and is constructed such that the controller includes: a mode switch for switching the image forming portion from a standby mode in which image forming is instantly enabled into a power-saving mode in which power supply to the image forming portion is partially stopped when no subsequent command has been received after a predetermined period elapsed from when image forming portion was operated last; a mode restoring portion for restoring the image forming portion from power-saving mode to standby mode when a subsequent command is received; and an image quality controller for performing image quality control of the image every time a predetermined time elapsed from when the image forming portion was last operated, and the image quality controller starts execution of the image quality control before the mode restoring portion restores the image forming portion from the power-saving mode to the standby mode.
摘要:
An image forming apparatus capable of performing monochrome printing and color printing in which all the developing units share a single development transformer is constructed such that at the time of monochrome printing the photoreceptor drums for colors are stopped rotating while all the developing units are constantly applied with a high voltage. Further, the cumulative operation time in which the black photoreceptor drum has been operated for monochrome printing is calculated so that the color-printing photoreceptor drums which are stopped during monochrome printing are rotationally driven by a predetermined angle when the cumulative operation time exceeds predetermined fixed time. Thus, the surface of each color-printing photoreceptor drum that is being worn is restored by making the fresh surface of the drum oppose the associated color developing unit, whereby it is possible to prevent occurrence of defects on the surface of each photoreceptor drum.
摘要:
An image forming apparatus includes a developing device having a toner supply sensor, a toner supply device supplying toner to the developing device, a toner supply controller controlling toner supply from the toner supply device to the developing device based on predetermined conditions, a toner empty determiner determining whether toner is present inside the toner supply device. In the image forming apparatus, the toner supply device includes a storage for recoding multiple measured values of toner supply detected by the toner supply sensor, and the toner supply controller corrects the amount of toner supply, based on the moving average of multiple measured values of the amount of toner supply.
摘要:
An image forming apparatus includes a developing device having a toner supply sensor, a toner supply device supplying toner to the developing device, a toner supply controller controlling toner supply from the toner supply device to the developing device based on predetermined conditions, a toner empty determiner determining whether toner is present inside the toner supply device. In the image forming apparatus, the toner supply device includes a storage for recording multiple measured values of toner supply detected by the toner supply sensor, and the toner supply controller corrects the amount of toner supply, based on the moving average of multiple measured values of the amount of toner supply.