An image forming system includes an image forming apparatus having an apparatus main body, a sheet feeding cassette, a manual bypass tray, an opening/closing detection part and a sheet feeding source setting part. The apparatus main body has an input part to which a printing instruction is input. The manual bypass tray is displaced into an open posture and into a close posture. The sheet feeding source setting part sets the sheet feeding cassette or the manual bypass tray as a sheet feeding source. When the opening/closing detection part detects that the manual bypass tray is displaced from the close posture to the open posture and the printing instruction is input to the input part, regardless of the sheet feeding source input to the input part, the sheet feeding source setting part sets the manual bypass tray as the sheet feeding source.

A sheet conveying device includes a sheet feed tray. The sheet feed tray includes a first guide and a second guide. The first guide has a first end portion. The first end portion has a first area located in a central portion in a width direction, and a second area located closer to one end in the width direction than the first area. The first end portion is inclined such that the first area is downstream of the second area in the sheet conveying direction. The second guide has an upper end portion located downstream of the first end portion of the first guide in the sheet conveying direction and above the first end portion. The upper end portion has a third area located in a central portion in the width direction and a fourth area located closer to an end in the width direction than the third area.

An image forming apparatus includes a control unit and an attachment detection unit to detect attachment of a cassette having a stacking portion that may be lifted by a motor. The control unit drives the motor to start lifting the stacking portion when cassette attachment is detected and stops when the stacked uppermost sheet is detected at a sheet feed position, at which time the presence or absence of the stored sheet is determined based on a detection signal output by a sheet presence/absence detection unit. In a case where there is no change in the detection signal output from the sheet presence/absence detection unit when the attachment of the cassette is detected, the control unit determines that a failure of the sheet presence/absence detection flag occurred.

An image forming apparatus includes an apparatus body that forms an image on a recording material; a drawn-out unit that is provided so as to be drawable from the apparatus body and has a mount region on which the recording material is mounted; and a guide unit that is provided on the drawn-out unit and guides the recording material to a position where the recording material is to be mounted on the mount region. The guide unit has a guide surface that guides an end of the recording material, a hook part that is hooked onto the drawn-out unit and determines a position relative to the drawn-out unit, and a release part that releases the hook part from the drawn-out unit by being operated by a user from a guide surface side.

An image forming apparatus has: a cassette which stores a sheet; a pickup roller which picks up the sheet inside the cassette; a feed roller which feeds the sheet picked up by the pickup roller toward an image forming portion; and a retard roller which is pressed against the feed roller and forms a separation nip. In addition, the image forming apparatus has a conveying guide which guides the sheet picked up by the pickup roller to the separation nip. A first guide member of the conveying guide is configured to be slidable in a drawing direction when the feed roller is replaced, and the conveying guide is formed of a material whose property of light transmittance of light having a wavelength of 360 nm to 420 nm is 80% or more. The feed roller is detachable from the one end of a shaft in a state in which the cassette is drawn out along the rail and the conveying guide is slid in the drawing direction.

Sheets are set on the top face of a lift plate. A lift mechanism makes a lift plate ascend and descend. A sheet feeding roller and a distance sensor are provided over the lift plate. The distance sensor measures a distance (measured distance) to a measurement target placed below. Based on the measured distance before the lift plate is raised, the controller calculates a remaining quantity value indicating a remaining quantity of sheets. When, after the lift plate starts to rise, the recognized measured distance becomes equal to or smaller than the upper limit distance, the controller makes the lift mechanism stop raising the lift plate.

An image forming apparatus includes a cassette, an image forming unit configured to form an image on a sheet fed from the cassette a set position, a guide rail configured to draw out the cassette from the set position, and a movable stopper unit that regulates a movement of the cassette in a draw-out direction by abutting with the cassette while the cassette is drawn out from the set position along the guide rail. The movable stopper unit includes a regulating portion movable between a regulating position where the regulating portion regulates a movement of the cassette within a moving trajectory of the cassette in moving in the draw-out direction and a retracting position where the regulating portion is located outside of the moving trajectory and does not regulate the movement of the cassette, and an urging portion configured to urge the regulating portion to the regulating position.

A medium passage switching mechanism disposed on a casing of an image forming device, includes a medium tray, a guiding component and a linking component. An entrance passage, a first exit passage and a second exit passage are formed inside the casing. The medium tray is pivoted to the casing. The guiding component is pivoted to the casing. The linking component is a one-piece structure and movably connected to the medium tray and the guiding component. When the medium tray pivots relative to the casing, the medium tray drives the linking component to drive the guiding component to pivot relative to the casing, so that the guiding component can guide a medium to enter into the first exit passage or the second exit passage selectively from the entrance passage.

A medium passage switching mechanism disposed on a casing of an image forming device, includes a medium tray, a guiding component and a linking component. An entrance passage, a first exit passage and a second exit passage are formed inside the casing. The medium tray is pivoted to the casing. The guiding component is pivoted to the casing. The linking component is a one-piece structure and movably connected to the medium tray and the guiding component. When the medium tray pivots relative to the casing, the medium tray drives the linking component to drive the guiding component to pivot relative to the casing, so that the guiding component can guide a medium to enter into the first exit passage or the second exit passage selectively from the entrance passage.

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.