An image forming apparatus includes: an image forming unit configured to form an image on a paper sheet; a conveying unit configured to convey the paper sheet to the image forming unit at a first conveyance speed and convey the paper sheet in the image forming unit at a second conveyance speed; a trouble detecting unit configured to detect a trouble; and a control unit configured to control the conveyance of the paper sheet in the conveying unit and the image formation on the paper sheet in the image forming unit, wherein, when the trouble detecting unit detects a trouble from the paper sheet being conveyed, and the control unit controls the conveying unit to perform a purging process to discharge a troubled paper sheet to the outside of the apparatus, the control unit controls a conveyance speed to be equal to the second conveyance speed.

A fixing device includes a clutch provided between a driving motor and a rotary cam, and a control unit. In a case in which press-contact force of the pressure roller is a high load, when a jam state has been detected, the control unit transmits power to the rotary cam by switching the clutch to a power transmission state, and stops the driving motor at the time of rotation of the rotary cam by a predetermined angle.

Upon occurrence of a paper jam at a circulation conveyer with a switching direction being set at a paper discharge guiding direction, a controller performs control of maintaining the switching direction at the paper discharge guiding direction and discharging sheets at a section of the circulation conveyer downstream of a position of the paper jam, the printing conveyer, and the paper discharger. Upon occurrence of the paper jam with the switching direction being set at a circulation guiding direction, the controller performs control of switching the switching direction to the paper discharge guiding direction after a sheet passing a switch exits the switch, and discharging the sheets at the section of the circulation conveyer downstream of the position of the paper jam, the printing conveyer, and the paper discharger.

A system includes an image forming apparatus and at least one information processing apparatus, wherein the image forming apparatus includes a storage unit configured to store recording materials, a feeding unit configured to feed the recording materials, a support member configured to support the recording materials, a control unit including a first detection unit configured to detect a movement of the support member and a second detection unit configured to detect a conveyance failure, and a transmission unit configured to transmit data about the movement and data about a detection result to the at least one information processing apparatus, wherein the at least one information processing apparatus includes a storage unit configured to store the data transmitted from the transmission unit, and an analysis unit configured to analyze whether a cause of the conveyance failure is due to a replenishment of the recording materials.

Provided are an image forming apparatus and methods for controlling the apparatus, which includes a central processing unit (CPU) configured to set whether to operate an air blowing fan before a paper type detection sensor detects a type of sheet. In a case where a setting to blow the air is made by the CPU, the air blowing fan blows the air when a sheet feed unit feeds the sheet before the paper type detection sensor detects the type of the sheet. In a case where a setting not to blow the air is made by the CPU, the air blowing fan does not blow the air when the sheet feed unit feeds the sheet before the paper type detection sensor detects the sheet type.

An image forming apparatus includes a primary transfer unit, a secondary transfer unit, a registration roller pair placed upstream of the secondary transfer unit in a sheet transport direction, and a drive unit driving the registration roller pair. In addition, a detection sensor unit is placed on a sheet transport path downstream of the secondary transfer unit and detects a sheet transported after a toner image is secondary transferred by the secondary transfer unit, and a transport unit transports the sheet after the secondary transfer. A control unit stops the drive unit when it determines absence of the sheet on the sheet transport path based on a signal from the detection sensor unit when a predetermined time based on an interval of time, which is from when the control unit controls the drive unit and starts to transport the sheet by the registration roller pair to when a leading edge of the sheet reaches the detection sensor unit, has elapsed, or when an interval of time, which is taken from when the control unit controls the drive unit and starts to transport the sheet by the registration roller pair to when the leading edge of the sheet reaches the transport unit, has elapsed.

If a sheet is jammed while conveyed, whether the jammed sheet and a sheet preceding the jammed sheet have been generated by cutting an uncut sheet from which the jammed sheet is derived is determined. If generated, a printing apparatus re-prints a plurality of images including an image of the jammed sheet on a sheet, and the cutting apparatus cuts the re-printed sheet. If the jammed sheet and the preceding sheet have been generated, the printing apparatus re-prints a plurality of images including an image of the jammed sheet on a sheet, the cutting apparatus cuts the re-printed sheet, and a sheet that includes the same image as the preceding sheet is discharged to a different discharge destination from that of the preceding sheet.

An image forming apparatus includes a toner image carrier, a transfer roller, a fixing device, a movable chute, a movement device, and a controller. The transfer roller forms a transfer nip with the toner image carrier. The fixing device includes a rotatable heating body and a rotatable pressure body configured to form a fixing nip with the rotatable heating body. The movable chute guides the sheet and is movable between a first position and a second position located further away, than the first position, from a straight line connecting a downstream edge of the transfer nip and an upstream edge of the fixing nip. The controller controls the movement device to move the movable chute only between the first position and the second position. The movable chute is movable to a third position located further away, than the second position, from the straight line.

An image forming apparatus includes an image forming device; a fixing device; a first transport route; a second transport route; a branch guide that assumes a first posture and a second posture; a sheet contact member that assumes a non-contact posture and a contacting posture; a detection object that assumes a first posture, when the branch guide assumes the first posture and when the sheet contact member assumes the non-contact posture, and assumes a second posture, when the branch guide assumes the second posture and when the sheet contact member assumes the contacting posture; and a sensor that outputs a first signal, when the detection object is in the first posture, and outputs a second signal, when the detection object is in the second posture.

A sheet transport device includes a first transport route, a roller, a second transport route, a switching nail, a lever, a sheet detection piece, a cam, an intermediate rotary member, a rotary member, a sensor, a driver, and a controller. The controller controls the driver to switch the switching nail between a first transport position and a second transport position, decides that the sheet is transported through first transport route, when the sheet detection piece retreats contacted by the sheet on the first transport route, with the switching nail being set to the first transport position, and the sensor detects that the rotary member is in the second posture, and decides that the switching nail has been switched from the first transport position to the second transport position, when the sensor detects that the rotary member is in the second posture, after the sheet has passed the sheet detection piece.