An image forming apparatus includes: a transporter; an image former; a reflective optical sensor; an image density adjuster; and a controller. The image former includes: a photoreceptor; a charger; an exposer; a developer; a transferor; and a fuser. The reflective optical sensor is provided opposite to the photoreceptor across a conveyance path. During image density adjustment, the controller forms a predetermined patch toner image on the photoreceptor, irradiates the patch toner image with light, and control the image density adjuster to adjust image density based on reflected light from the patch toner image. During image forming, the controller causes the reflective optical sensor to emit light on timing that a predetermined leading edge area of the recording area passes, and decides based on reflected light therefrom whether a width in the main scanning direction of a recording medium is longer than a predetermined reference length.

An image forming device includes a transfer unit that transfers a toner image onto a recording medium that has first and second surfaces and is conveyed in a conveyance direction; a main heating unit arranged downstream of the transfer unit in the conveyance direction, and which contacts and heats the recording medium and fixes the toner image onto the recording medium; a reversing unit that reverses front and back of the recording medium having a first toner image fixed onto the first surface; and a preheating unit arranged between the transfer and main heating units in the conveyance direction and that heats the recording medium having a second toner image transferred onto the second surface. The preheating unit heats the recording medium so that a temperature of the first surface is lower than a softening point of a toner before the recording medium is heated by the main heating unit.

A sheet conveying device can selectively execute a first conveyance process of conveying sheets on a first tray and discharging the sheets onto a second tray, a second conveyance process of conveying the sheets on the first tray and discharging the sheets onto a third tray, or a third conveyance process of conveying the sheets on the third tray and discharging the sheets onto the second tray. A control device records conveyance history information indicating by which conveyance processes each of the sheets on the first tray has been conveyed in a storage device. Furthermore, the control device causes the sheet conveying device to sequentially select the first conveyance process or the third conveyance process for each of the sheets based on the conveyance history information and execute the selected process.

An image reading device includes a reading device body and a document feeder that is turnably attached on the upper side of the reading device body with hinge devices. An extended portion that extends outward from a rear frame is formed on a beam frame fixing the rear frame and a front frame of the document feeder at a predetermined interval, and a third coupling portion coupled to the turning member of the hinge device is formed in the extended portion.

An image forming apparatus includes: a transporter; an image former; a reflective optical sensor; an image density adjuster; and a controller. The image former includes: a photoreceptor; a charger; an exposer; a developer; a transferor; and a fuser. The reflective optical sensor is provided opposite to the photoreceptor across a conveyance path. During image density adjustment, the controller forms a predetermined patch toner image on the photoreceptor, irradiates the patch toner image with light, and control the image density adjuster to adjust image density based on reflected light from the patch toner image. During image forming, the controller causes the reflective optical sensor to emit light on timing that a predetermined leading edge area of the recording area passes, and decides based on reflected light therefrom whether a width in the main scanning direction of a recording medium is longer than a predetermined reference length.

A document feeder includes a device body, and an opening and closing cover which is provided to be openable and closable with respect to the device body, and including a paper feed roller and a paper feed roller drive shaft on the device body. The document feeder includes a guide member, which is mounted rotatably to the paper feed roller drive shaft on an outer side of the paper feed roller in a roller axis direction thereof. The guide member guides a document being conveyed, in a state where the opening and closing cover is closed, by being opposed to the paper feed roller drive shaft in a predetermined orientation.

A decoloring apparatus includes a sheet conveying unit, a scanner, a decoloring unit, and a controller. The decoloring unit decolors the image on the sheet conveyed through the sheet conveying unit. The decoloring unit is positioned downstream of the scanner in a sheet conveying direction. A distance along the sheet conveying direction between the scanner and the decoloring unit is shorter than a length of a first predetermined sheet size and longer than a length of a second predetermined sheet size. A controller determines whether the sheet conveyed by the sheet conveying unit is the first predetermined sheet size or the second predetermined sheet size. The controller performs a mode limiting process if the sheet size is determined to be the first predetermined sheet size.

In a medium conveying device, a projector projects light, a projection light amount of the light changes, at every fixed time, to a first projection light amount and a second projection light amount less than the first projection light amount, a receiver receives the light projected from the projector, a processor determines, at fixed sampling timings, whether a reception light amount of the receiver is at a first reception light level or a second reception light level smaller than the first reception light level, determines, when the reception light amount alternately changes to the first reception light level and the second reception light level, that a medium is not present on a conveying path, and determines, when the reception light amount is fixed to either the first reception light level or the second reception light level, that the medium is present on the conveying path.

An image forming apparatus comprises a tray, a conveyor, a detector and a movement mechanism. The tray accommodates at least one document. The conveyor conveys the document placed on the tray. The detector detects that the document is placed on the tray. The movement mechanism moves the tray from a first position to a second position closer to the conveyor than the first position based on the detection that the document is placed on the tray, and after moving the tray from the first position to the second position, moves the tray to the first position based on a setting of a mixed stacking mode in which mixing of the documents with different sizes on the tray is permitted.

A sheet conveying apparatus includes a transmitting mechanism, a movable member, and a control portion to input a signal having first and second levels. The transmitting mechanism transmits driving force and includes a spring clutch and an electromagnetic clutch. The driving force pivotally moves the movable member. The spring clutch idles by a slackness of a spring when the rotation in a second direction is inputted to the transmitting mechanism and the movable member is regulated from pivoting at a predetermined position. The control portion inputs the signal to the transmitting mechanism such that the state electromagnetic clutch state changes the engagement state to the disengagement state through an intermediary state gradually varying a length of time where the signal of the first level is inputted into the electromagnetic clutch after the movable member reaches the predetermined position by inputting the rotation in the second direction to the transmitting mechanism.