An image reading apparatus includes a first opening/closing unit to openably and closeably support a sheet conveyance portion with respect to an image reading portion, and a second opening/closing unit to openably and closeably support the sheet conveyance portion with respect to the image reading portion. The first opening/closing unit includes a first spring to urge the sheet conveyance portion in a direction in which the sheet conveyance portion moves from a closed position toward an opened position, and the second opening/closing unit includes a second spring to urge the sheet conveyance portion in the direction in which the sheet conveyance portion moves from the closed position toward the opened position and an oil damper to attenuate vibration energy of the sheet conveyance portion. The first opening/closing unit does not include an oil damper.

A sheet discharge device includes: a sheet discharge portion; a sheet stacking portion having a sheet stacking surface for stacking a sheet discharged from the sheet discharge portion; and a stopper in the sheet stacking portion against which, for alignment, the leading end of the sheet discharged from the sheet discharge portion is thrust. The stopper has a support portion, a restricting portion, and an urging mechanism. The restricting portion is supported pivotally on a pivot shaft on the support portion, and is arranged either in a retracted position to lie flat substantially horizontally along the sheet stacking surface or in a restricting position to stand upright substantially vertically to the sheet stacking surface. The urging mechanism urges the restricting portion, when in retracted position, in a direction from restricting position to retracted position and, when in restricting position, in a direction from retracted position to restricting position.

A sheet discharge device includes: a sheet discharge portion; a sheet stacking portion having a sheet stacking surface for stacking a sheet discharged from the sheet discharge portion; and a stopper in the sheet stacking portion against which, for alignment, the leading end of the sheet discharged from the sheet discharge portion is thrust. The stopper has a support portion, a restricting portion, and an urging mechanism. The restricting portion is supported pivotally on a pivot shaft on the support portion, and is arranged either in a retracted position to lie flat substantially horizontally along the sheet stacking surface or in a restricting position to stand upright substantially vertically to the sheet stacking surface. The urging mechanism urges the restricting portion, when in retracted position, in a direction from restricting position to retracted position and, when in restricting position, in a direction from retracted position to restricting position.

A sheet conveying device includes a tray, a device body having a conveying route of a sheet and supporting the tray, a side guide supported by the tray to be movable in a first direction intersecting with a conveying direction of the sheet and contacting an end portion in the first direction of the sheet placed on the tray, a cover rotatable with respect to the device body and covering the conveying route, and a lock lever locking the cover to the device body and provided in a position overlapping the side guide in a second direction intersecting with the conveying direction and the first direction. The lock lever is rotatable between a lock position where the cover is locked and a release position where the cover is released. The side guide includes a first notched portion facing a rotation track of the lock lever with a gap.

A sheet conveying device includes a tray, a device body having a conveying route of a sheet and supporting the tray, a side guide supported by the tray to be movable in a first direction intersecting with a conveying direction of the sheet and contacting an end portion in the first direction of the sheet placed on the tray, a cover rotatable with respect to the device body and covering the conveying route, and a lock lever locking the cover to the device body and provided in a position overlapping the side guide in a second direction intersecting with the conveying direction and the first direction. The lock lever is rotatable between a lock position where the cover is locked and a release position where the cover is released. The side guide includes a first notched portion facing a rotation track of the lock lever with a gap.

An image forming apparatus includes a casing, an image forming unit movable between an accommodated position and a shifted position, an actuator, an urging member, a cam, and a contact portion. The actuator includes a pivot shaft and a protrusion protruding therefrom. The protrusion at a standby position crosses a conveyance path and is contactable with a sheet conveyed along the conveyance path. When the image forming unit is at the accommodated position, the contact portion and the cam contact each other and maintain the protrusion at the standby position against an urging force of the urging member. As the image forming unit moves from the accommodated position to the shifted position, the contact portion and the cam move away from each other such that the protrusion pivots from the standby position, by the urging force, to a retracted position at which the protrusion is retracted from the conveyance path.

An image forming apparatus includes a casing, an image forming unit movable between an accommodated position and a shifted position, an actuator, an urging member, a cam, and a contact portion. The actuator includes a pivot shaft and a protrusion protruding therefrom. The protrusion at a standby position crosses a conveyance path and is contactable with a sheet conveyed along the conveyance path. When the image forming unit is at the accommodated position, the contact portion and the cam contact each other and maintain the protrusion at the standby position against an urging force of the urging member. As the image forming unit moves from the accommodated position to the shifted position, the contact portion and the cam move away from each other such that the protrusion pivots from the standby position, by the urging force, to a retracted position at which the protrusion is retracted from the conveyance path.

A buffer unit receives a sheet and temporarily holds a predetermined number of sheets so as to be overlaid on one another. A stacking unit stacks the predetermined number of sheets conveyed toward a first direction. A moving unit comes into contact with an uppermost sheet among the predetermined number of sheets stacked on the stacking unit and moves the uppermost sheet further toward the first direction. A regulating unit comes into contact with an end portion of the stack of sheets on the stacking unit to regulate the position of the stack of sheets. A control unit controls the predetermined number of sheets.

A buffer unit receives a sheet and temporarily holds a predetermined number of sheets so as to be overlaid on one another. A stacking unit stacks the predetermined number of sheets conveyed toward a first direction. A moving unit comes into contact with an uppermost sheet among the predetermined number of sheets stacked on the stacking unit and moves the uppermost sheet further toward the first direction. A regulating unit comes into contact with an end portion of the stack of sheets on the stacking unit to regulate the position of the stack of sheets. A control unit controls the predetermined number of sheets.

A conveying unit 2including conveyor belts 7, a stopper 3positioning a sheet S at a folding position P on a conveying path 2, a knife-type folding unit 4, an anti-bounce roller unit 16having rollers 25a, 25b, and a motor 22 are provided. The rollers can be moved back and forth. A roller rotational speed monitoring unit 31 and a roller position setting unit 32 operatively connected to the motor are further provided. In setting mode, the rollers are moved from an upstream or a downstream of a tail end of the sheet positioned at the folding position P toward the tail end at a constant speed and stopped when the rotational speed of the rollers changes.