A post-processing apparatus includes a storing unit in which plural recording media are stored for performing post-processing and a transport member that transports a recording medium to the storing unit as a result of rotating while being in contact with a surface of the recording medium. The transport member includes a blade that comes into contact with a recording medium and a reinforcing portion that reinforces a strength of a portion of the blade that does not come into contact with the recording medium.

A post-processing apparatus includes an ejection tray receiving a recording medium that is ejected, an elastic member urging the ejection tray upward in a vertical direction, a moving mechanism causing the ejection tray to move up and down in the vertical direction, and a driving source driving the moving mechanism.

In a sheet discharge device, upon a discharge of a sheet bundle onto a discharge tray, a lowering control portion lowers the discharge tray by a predetermined lowering distance. After the discharge tray is lowered by the lowering control portion, a lifting control portion waits until a front end of an initial sheet of a next sheet bundle becomes in a state of protruding from a discharge port, and then lifts the discharge tray until an upper-surface detection sensor detects that an upper surface of sheet bundles stacked on the discharge tray has reached a predetermined height.

The present invention is to provide a sheet stacking device for stacking sheets on which an image is formed, in which an initial operation time at the time the device is turned on is shortened, and, at the same time, the initial operation is simplified. This configuration enables reduction in operation noise and a prompt start at the time when the device is started.

The present invention is to provide a sheet stacking device for stacking sheets on which an image is formed, in which an initial operation time at the time the device is turned on is shortened, and, at the same time, the initial operation is simplified. This configuration enables reduction in operation noise and a prompt start at the time when the device is started.

A sheet feeder includes an apparatus main body, a sheet housing unit, and a sheet feeding unit. The sheet housing unit includes a housing space, a lift plate, an elevating mechanism, and a side fence. The elevating mechanism includes a pair of first wires, a pair of second wires, first pulleys, second pulleys, a reel, and a pair of first connecting members. The reel winds up the pair of first wires and the pair of second wires. The pair of first connecting members are connected to be relatively movable with respect to the lift plate in a vertical direction, causes a relative position to vary with respect to the lift plate in a vertical direction in accordance with a weight of the plurality of sheets loaded on the lift plate, and causes the lift plate to move upward when the weight is lighter than a predetermined value.

A sheet housing device includes a supporting member, a driving pulley, a driven pulley, a timing belt, a driving part, a stacking tray and rotating members. The driving pulley and the driven pulley are rotatably provided at one end and another end in a longitudinal direction of the supporting member, respectively. The timing belt is windingly stretched between the pulleys. The driving part drives and rotates the driving pulley. The stacking tray is fixed to the timing belt and attached to the supporting member to move between both ends of the supporting member according to rotation of the timing belt. The rotating members are provided at another end side more than a rotational center of the driving pulley and at both outsides more than the timing belt and are rotatably attached by having a rotating shaft parallel to a rotating shaft of the driving pulley.

A sheet housing device includes a supporting member, a driving pulley, a driven pulley, a timing belt, a driving part, a stacking tray and rotating members. The driving pulley and the driven pulley are rotatably provided at one end and another end in a longitudinal direction of the supporting member, respectively. The timing belt is windingly stretched between the pulleys. The driving part drives and rotates the driving pulley. The stacking tray is fixed to the timing belt and attached to the supporting member to move between both ends of the supporting member according to rotation of the timing belt. The rotating members are provided at another end side more than a rotational center of the driving pulley and at both outsides more than the timing belt and are rotatably attached by having a rotating shaft parallel to a rotating shaft of the driving pulley.

A sheet storage device includes a sheet storage movable in an up-and-down direction, to stack and store sheets conveyed in a conveyance direction. The sheet storage moves down according to weight of the sheets stacked in the sheet storage.

A sheet storage device includes a sheet storage movable in an up-and-down direction, to stack and store sheets conveyed in a conveyance direction. The sheet storage moves down according to weight of the sheets stacked in the sheet storage.