Abstract: The present invention relates to an image forming apparatus to which a process cartridge can be detachably attached, comprising: a housing body to which the process cartridge is attached; an opening and closing portion for detachably attaching the process cartridge; and securing means for securing the process cartridge to a position where an image can be formed. The securing means is turned when the process cartridge is detached and attached, the image forming apparatus further comprises force-applying means which applies a force to the process cartridge to a position where the process cartridge is secured or a position where the process cartridge is opened, and an image is not formed when the securing means is in a phase other than a process cartridge securing phase.

Abstract: An image forming apparatus of the present invention has a first opening and closing unit that is opened to thereby expose said convey path and a second opening and closing unit that have a recording material stacking section and can open the image forming unit to support intermediate transfer. The second opening and closing unit can be operated be to open or close at the time that the first opening and closing unit is opened.

Abstract: The present invention relates to an image forming apparatus to which a process cartridge can be detachably attached, comprising: a housing body to which the process cartridge is attached; an opening and closing portion for detachably attaching the process cartridge; and securing means for securing the process cartridge to a position where an image can be formed.

Abstract: A sheet feeding apparatus according to the present invention includes: a feed rotary member rotationally driven in a sheet feeding direction; a retard rotary member in contact with the feed rotary member under a predetermined pressure and rotationally driven in a direction opposite to the sheet feeding direction with a predetermined torque; and a pressure fluctuation restraining device for diminishing a change in a contact pressure of the retard rotary member for the feed rotary member generated at the time of drive transmission to the retard rotary member.

Abstract: A sheet feeding apparatus according to the present invention includes: a feed rotary member rotationally driven in a sheet feeding direction; a retard rotary member in contact with the feed rotary member under a predetermined pressure and rotationally driven in a direction opposite to the sheet feeding direction with a predetermined torque; and a pressure fluctuation restraining device for diminishing a change in a contact pressure of the retard rotary member for the feed rotary member generated at the time of drive transmission to the retard rotary member.

Abstract: An image forming apparatus includes an image forming portion for forming an image on a sheet. A separating and feeding portion feeds sheets stacked on a sheet supporting portion one-by-one toward the image forming portion. A sheet conveying portion conveys the sheets fed by the separating and feeding portion. Registration rollers of a variable rotating speed are disposed upstream of the image forming portion with respect to a sheet conveying direction. A sheet conveyance controlling portion causes the registration rollers to effect the conveyance of the sheets at a speed higher than the image forming speed in the image forming portion. Thereafter, the registration rollers are decelerated so as to assume substantially the same speed as the image forming speed at a timing earlier than a latest image forming timing in the image forming portion.

Abstract: An image forming apparatus includes image forming portion for forming an image on a sheet, separating and feeding portion for feeding sheets stacked on sheet supporting portion one by one toward the image forming portion, sheet conveying portion for conveying the sheets fed by the separating and feeding portion, registration rollers of a variable rotating speed disposed upstream of the image forming portion with respect to a sheet conveying direction, and sheet conveyance controlling portion for causing the registration rollers to effect the conveyance of the sheets at a speed higher than the image forming speed in the image forming portion, and thereafter decelerating the registration rollers so as to assume substantially the same speed as the image forming speed at timing earlier than the latest image forming timing in the image forming portion.