Various embodiments disclose a method of detecting a media jam in a printer. The method includes causing a sensor unit of the printer to generate a sensor signal indicative of a reflectance characteristic associated with a surface of a roller of the printer. Further, the method includes receiving the sensor signal from the sensor unit of the printer and comparing the reflectance characteristic to a threshold reflectance characteristic associated with the roller. Furthermore, in response to the comparison, the method includes generating an output signal to indicate whether the media jam has occurred. For example, a first output signal indicates unsuccessful passage of a media along a media path of the printer, when the reflectance characteristic exceeds the threshold reflectance characteristic and a second output signal indicates successful passage of the media along the media path, when the reflectance characteristic is equal to or below the threshold reflectance characteristic.

An image forming apparatus includes a print engine to form an image on recording medium, a sensor including first and second electrodes disposed to oppose each other based on a recording medium transport path, along which the recording medium is transported, and to detect a capacitance between the first and second electrodes, and a processor to determine a state of the recording medium fed along the recording medium transport path by using the capacitance detected by the sensor and to control the print engine based on the state of the recording medium.

A post-processing apparatus performs post-processing on a paper sheet conveyed from a previous stage side, and includes: a corrector that performs bend correction on the paper sheet, in accordance with one of a plurality of bend correction methods; a post-processor that performs the post-processing on the paper sheet subjected to the bend correction performed by the corrector; and a hardware processor that selects one of the plurality of bend correction methods, on the basis of a bend correction accuracy corresponding to a product to be created by the post-processing being performed by the post-processor, and a productivity of the product, wherein from the plurality of bend correction methods, the hardware processor selects a bend correction method that reduces a difference between a post-processing time required for the post-processor to perform the post-processing and a correction time required for the corrector to perform the bend correction on the paper sheet.

An image forming apparatus includes: a feed tray that contains printing paper therein; a user authentication unit that authenticates a user who is permitted to print; a paper loading detection unit that detects printing paper loaded into the feed tray; a memory device that stores a user authenticated as a paper-supplementing user; a paper feeding mechanism that feeds the printing paper from the feed tray; a paper jam detection unit that detects a paper jam; and a controller that controls a print job. The controller, when a paper jam has occurred, determines whether or not the paper jam is due to the paper-supplementing user having loaded the printing paper in an improper manner. Upon determining that the paper jam is due to the paper-supplementing user having loaded the printing paper in an improper manner, the controller, subsequently when the paper-supplementing user uses, requests that a loading condition be checked.

When a sheet jam is detected, a processor may perform the following process. In a case where a sheet is spanning a first conveyance path and a drawer unit, the processor maintains a lock unit in a locked state by supplying power to the lock unit via the drawer unit from a power supply without depending on whether a door is in an open state or a closed state. In a case where a sheet is not spanning the first conveyance path and the drawer unit, the processor controls supplying and disconnecting of power to the drawer unit from the power supply in accordance with whether the door is in a closed state or an open state.

An image forming apparatus includes a first unit, a second unit fixed to the first unit at a portion upstream of the first unit in a conveyance direction in which the sheet is conveyed, and an electric board. In the image forming apparatus, a disposition of the electric board is restricted by the first unit and the second unit.

A contact member comes into contact with a back surface of a recording material between a nip portion and a transfer portion in a conveyance direction of the recording material. The contact member is capable of being located at a first position, a second position, and a third position. A detection unit detects a position of the contact member so that the detection unit can detect the first position, the second position, and the third position. The contact member reaches the third position by being biased by the recording material from the second position.

An image forming apparatus includes a cassette that has a placement plate on which a sheet is set, a paper feed roller, a raising/lowering mechanism that raises and lowers the placement plate, a print unit, a sheet sensor, an upper limit sensor and a control unit. The control unit recognizes, based on an output of the sheet sensor, that the sheet supplied from a paper feed device reaches an installation position of the sheet sensor. The control unit detects, based on an output of the upper limit sensor, that the paper feed roller reaches a predetermined upper limit position or that the raising/lowering mechanism raises the placement plate such that the sheet reaches a feed position and uses the sheet sensor and the upper limit sensor so as to detect that the paper feed device encounters overload.

An image forming apparatus that forms an image on a long paper sheet conveyed along a conveyance path extending from a paper feeding side to a paper discharging side includes: an image forming unit configured to transfer a toner image onto the long paper sheet; a fixing unit configured to fix the toner image onto the long paper sheet; a paper existence determining unit configured to determine whether the long paper sheet exists along the conveyance path; a temperature determining unit configured to determine whether a fixing temperature of the fixing unit is equal to or lower than a predetermined temperature when the paper existence determining unit determines that the long paper sheet exists along the conveyance path; and a state setting unit configured to disable a fixing operation of the fixing unit when the temperature determining unit determines that the fixing temperature is higher than the predetermined temperature.

A sheet processing system according to an embodiment includes a tray that supports a sheet on opposite sides of the sheet orthogonal to a conveyance direction of the sheet. The tray includes a first adjustable support and second adjustable support positioned opposite the first adjustable support in the direction orthogonal to the conveyance direction of the sheet. A skew sensor detects a skew angle of the sheet conveyed to the tray. A corner sensor detects positions of each corner on a front end in the downstream direction of the sheet conveyed to the tray. A controller controls movement of the first and second adjustable supports based on the detected skew angle and the detected positions of each corner on the front end of the sheet conveyed to the tray so that the sheet is conveyed to the tray without jamming.