Abstract: An image forming apparatus includes: image bearing members; a belt unit including an endless belt; a slackness forming unit for performing a first function of forming a belt slacking region, at least at a portion where the belt opposes the image bearing members, by causing the slackness forming unit to act on the belt unit and for performing a second function of eliminating the belt slacking region; and a guiding unit for guiding the belt unit so that the slackness forming unit performs the first function in a state in which the belt is spaced from the image bearing members and so that the slackness forming unit performs the second function in a state in which the belt slacking region contacts the image bearing members.

Abstract: An image forming apparatus includes: image bearing members; a belt unit including an endless belt; a slackness forming unit for performing a first function of forming a belt slacking region, at least at a portion where the belt opposes the image bearing members, by causing the slackness forming unit to act on the belt unit and for performing a second function of eliminating the belt slacking region; and a guiding unit for guiding the belt unit so that the slackness forming unit performs the first function in a state in which the belt is spaced from the image bearing members and so that the slackness forming unit performs the second function in a state in which the belt slacking region contacts the image bearing members.

Abstract: In a constitution provided with no primary-transfer roller, in order to ensure a contact length between each of photosensitive drums and an intermediary transfer belt, the photosensitive drums are disposed in entering amounts at a plurality of levels with respect to a stretching surface of the intermediary transfer belt, and therefore an apparatus is upsized in a height direction. In order to avoid this, four image bearing members are arranged, along the intermediary transfer belt, in the same entering amount with respect to the stretching surface of the intermediary transfer belt, and a depressing member for depressing a belt surface between two central image bearing members toward an outside is provided.

Abstract: An image forming apparatus includes a fixing unit heating an image formed on a recording medium and disposed along a conveying path conveying the recording medium. The conveying path includes a first guide plate, discharge guide plate portions and second guide plate portion as conveyance guide plates guiding the recording medium. Partition walls and vertical walls are disposed at positions facing these guide plate portions. The air current guide portion guides air taken in from intake ports through an intake guide portion between the respective guide plate portions and each walls.

Abstract: An image forming apparatus includes a manual feed portion provided on a side surface of a housing that accommodates an image forming portion and having an abutting portion against which a downstream end in a sheet feeding direction of a sheet inserted into a gap between the manual feed portion and the side surface abuts. The manual feed portion also includes a holding portion configured to hold the sheet such that a sheet surface is held along the side surface of the housing in the condition in which the downstream end of the sheet abuts against the abutting portion.

Abstract: An image forming apparatus includes a manual feed portion provided on a side surface of a housing that accommodates an image forming portion and having an abutting portion against which a downstream end in a sheet feeding direction of a sheet inserted into a gap between the manual feed portion and the side surface abuts. The manual feed portion also includes a holding portion configured to hold the sheet such that a sheet surface is held along the side surface of the housing in the condition in which the downstream end of the sheet abuts against the abutting portion.

Abstract: An image forming apparatus includes a cover configured to open/close with respect to an apparatus main body of the image forming apparatus, a pullout unit, a locking member configured to lock the pullout unit according to an operation of inserting the pullout unit into the apparatus main body, and an abutting member movable between a position where the abutting member regulates the closure of the cover by abutting against the cover and a position where the abutting member does not regulate the closure of the cover. When the locking member does not lock the pullout unit, the abutting member is positioned at the position where the abutting member regulates the closure of the cover.

Abstract: If a jam detecting portion detects a sheet jam, a rear end position of the jammed sheet is computed based on information, when a rear end of the jammed sheet is located within an area A1 and a length Ls of the jammed sheet in a conveying direction of the sheet is equal to or shorter than a distance L between the area A1 and an area A2, driving operations of a pre-registration roller and a registration roller are controlled so that the jammed sheet is conveyed to a downstream until a rear end of the sheet passes through a downstream end of the area A1. When Ls is longer than L, the pre-registration roller and the registration roller are controlled so that the jammed sheet is conveyed toward the upstream until the rear end of the sheet passes through an upstream end of the area A1.

Abstract: A recording material stacking apparatus equipped with a plurality of discharge ports and a plurality of stacking trays can be set to normal mode and large capacity stacking mode each having a different maximum loading capacity. A stacking tray on the upper side has a plurality of lower limit positions and uses a lower limit position located on the upper side when normal mode is selected. On the other hand, it uses a lower limit position located on the lower side when the large capacity stacking mode is selected. The lower limit position located below a stacking tray on the upper side when this large capacity stacking mode is selected exists at a position in which it blocks a lower discharge port of sheets. Selection of the large capacity stacking mode and normal mode is executed according to a result of computation from data input through an input portion.

Abstract: If a jam detecting portion detects a sheet jam, a rear end position of the jammed sheet is computed based on information, when a rear end of the jammed sheet is located within an area A1 and a length Ls of the jammed sheet in a conveying direction of the sheet is equal to or shorter than a distance L between the area A1 and an area A2, driving operations of a pre-registration roller and a registration roller are controlled so that the jammed sheet is conveyed to a downstream until a rear end of the sheet passes through a downstream end of the area A1. When Ls is longer than L, the pre-registration roller and the registration roller are controlled so that the jammed sheet is conveyed toward the upstream until the rear end of the sheet passes through an upstream end of the area A1.

Abstract: If a jam detecting portion detects a sheet jam, a rear end position of the jammed sheet is computed based on information, when a rear end of the jammed sheet is located within an area A1 and a length Ls of the jammed sheet in a conveying direction of the sheet is equal to or shorter than a distance L between the area A1 and an area A2, driving operations of a pre-registration roller and a registration roller are controlled so that the jammed sheet is conveyed to a downstream until a rear end of the sheet passes through a downstream end of the area A1. When Ls is longer than L, the pre-registration roller and the registration roller are controlled so that the jammed sheet is conveyed toward the upstream until the rear end of the sheet passes through an upstream end of the area A1.

Abstract: If a jam detecting portion detects a sheet jam, a rear end position of the jammed sheet is computed based on information, when a rear end of the jammed sheet is located within an area A1 and a length Ls of the jammed sheet in a conveying direction of the sheet is equal to or shorter than a distance L between the area A1 and an area A2, driving operations of a pre-registration roller and a registration roller are controlled so that the jammed sheet is conveyed to a downstream until a rear end of the sheet passes through a downstream end of the area A1. When Ls is longer than L, the pre-registration roller and the registration roller are controlled so that the jammed sheet is conveyed toward the upstream until the rear end of the sheet passes through an upstream end of the area A1.

Abstract: A sheet processing apparatus includes an aligning member configured to align an end of a bundle of sheets including a folded sheet by engaging with the edge of the bundle of sheets, and a sheet processing unit configured to process the bundle of sheets having the end aligned by the aligning member. The end of the bundle of sheets engaged with the aligning member is opposite to a folded portion of the folded sheet.

Abstract: A sheet processing apparatus includes an aligning member and a shift conveying unit. The aligning member is movable in a width direction perpendicular to a sheet conveying direction and presses a sheet stack loaded on a sheet processing tray so as to align the sheet stack in the width direction. The unit is provided on the upstream side of the tray and conveys a sheet, shifting the sheet in the width direction. Being shifted by the unit, sheets are loaded at first and second loading positions on the tray. When sheets are loaded at the first loading position, the aligning member is moved to a first standby position corresponding to the first loading position in advance. When sheets are loaded at the second loading position, the aligning member is moved in advance to a second standby position corresponding to the second loading position.

Abstract: A bookbinding apparatus comprises, a stacking unit on which sheets are stacked; a folding portion which folds the sheets stacked on the stacking unit; a humidifying unit which humidifies portions of the sheets to be fold lines of a booklet before folding by the folding portion; and a controller which controls a humidifying condition at the time of the humidifying by the humidifying unit, wherein the humidifying condition is variable according to the sheets composing the booklet.

Abstract: An image forming apparatus includes a cover configured to open/close with respect to an apparatus main body of the image forming apparatus, a pullout unit, a locking member configured to lock the pullout unit according to an operation of inserting the pullout unit into the apparatus main body, and an abutting member movable between a position where the abutting member regulates the closure of the cover by abutting against the cover and a position where the abutting member does not regulate the closure of the cover. When the locking member does not lock the pullout unit, the abutting member is positioned at the position where the abutting member regulates the closure of the cover.

Abstract: A sheet processing apparatus is operable to cut an edge portion of a sheet. The sheet processing apparatus is operable to calculate a sheet utilization efficiency based on an area of the sheet before cutting and an area of a sheet obtained by cutting the edge portion.

Abstract: A sheet feeding device includes a sheet supporting portion which supports sheets, a restricting member which is movably disposed in the sheet supporting portion and is moved to a position according to the sheet supported by the sheet supporting portion, to restrict the position of the sheet; and a lock mechanism including a lock projection which is disposed in the restricting member so as to be pivotable in a movement direction of the restricting member and a plurality of lock grooves which are formed on a side of the sheet supporting portion and disengageably engage with the lock projection, so as to restrict movement of the restricting member in a direction reverse to a sheet restricting direction. The pivotal center of the lock projection in the lock mechanism is located downward of the position of an engaging portion between the lock projection and the lock groove.

Abstract: A recording material stacking apparatus equipped with a plurality of discharge ports and a plurality of stacking trays can be set to normal mode and large capacity stacking mode each having a different maximum loading capacity. A stacking tray on the upper side has a plurality of lower limit positions and uses a lower limit position located on the upper side when normal mode is selected. On the other hand, it uses a lower limit position located on the lower side when the large capacity stacking mode is selected. The lower limit position located below a stacking tray on the upper side when this large capacity stacking mode is selected exists at a position in which it blocks a lower discharge port of sheets. Selection of the large capacity stacking mode and normal mode is executed according to a result of computation from data input through an input portion.

Abstract: A recording material stacking apparatus equipped with a plurality of discharge ports and a plurality of stacking trays can be set to normal mode and large capacity stacking mode each having a different maximum loading capacity. A stacking tray on the upper side has a plurality of lower limit positions and uses a lower limit position located on the upper side when normal mode is selected. On the other hand, it uses a lower limit position located on the lower side when the large capacity stacking mode is selected. The lower limit position located below a stacking tray on the upper side when this large capacity stacking mode is selected exists at a position in which it blocks a lower discharge port of sheets. Selection of the large capacity stacking mode and normal mode is executed according to a result of computation from data input through an input portion.