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.

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 directed to providing a bill-separating-and-stacking unit with a simplified power-transmission structure by integrating driving units of a push plate and a shutter into a single unit. The bill-separating-and-stacking unit includes a sheet roller configured hit bills entering a bill-stacking space with a sheet, which is rotated, and configured to guide the bills to be stacked, a push plate configured to perform reciprocation and support the bills which are stacked in the bill-stacking space, a shutter which is rotated in one direction to be located in a stacking position so that the sheet of the sheet roller is rotatable to an upper side of the bill-stacking space when the bills are stacked, and is rotated in a direction opposite the one direction to be located in a separating position so that the sheet is prevented from protruding to the upper side of the bill-stacking space when the bills are separated, and a push-plate-and-shutter driving unit having a single driving source so that the push plate and the shutter are worked in conjunction with each other.

A removable raised tray system for a printing system generally includes a removable tray operatively arranged to receive print media thereon. The removable tray includes an upper tray surface having an electrically conductive material, a lower tray surface, and at least one tray leg that is connected to the removable tray, which is configured to support the removable tray at a position that is raised relative to a platform surface of a printer feeder or stacker. The at least one leg includes a releasable fastening assembly, such as a rare earth magnet, that releasably secures the removable tray to the platform surface thereby allowing the tray to easily attached and removed from the printer feeder or stacker. The electrically conductive material of the tray surface and the platform surface are electrically conductively connected to one another so as to prevent the build-up of static electricity.

A removable raised tray system for a printing system generally includes a removable tray operatively arranged to receive print media thereon. The removable tray includes an upper tray surface having an electrically conductive material, a lower tray surface, and at least one tray leg that is connected to the removable tray, which is configured to support the removable tray at a position that is raised relative to a platform surface of a printer feeder or stacker. The at least one leg includes a releasable fastening assembly, such as a rare earth magnet, that releasably secures the removable tray to the platform surface thereby allowing the tray to easily attached and removed from the printer feeder or stacker. The electrically conductive material of the tray surface and the platform surface are electrically conductively connected to one another so as to prevent the build-up of static electricity.

A sheet post-processing apparatus includes an apparatus body, a body frame, a sheet conveyance passage, an elevating tray, and an elevating unit. The elevating unit has a pair of rails. The body frame has a plurality of vertical frame members extending in the vertical direction and horizontal frame members that extends in a horizontal direction and is joined to the plurality of vertical frame members. The pair of rails are formed integrally with, among the plurality of vertical frame members, a pair of vertical frame members provided corresponding to a second side surface.

A sheet post-processing apparatus includes an apparatus body, a body frame, a sheet conveyance passage, an elevating tray, and an elevating unit. The elevating unit has a pair of rails. The body frame has a plurality of vertical frame members extending in the vertical direction and horizontal frame members that extends in a horizontal direction and is joined to the plurality of vertical frame members. The pair of rails are formed integrally with, among the plurality of vertical frame members, a pair of vertical frame members provided corresponding to a second side surface.

When a discharge count has exceeded a specified number of sheets, a sheet discharge device executes a process of moving down a discharge tray by a specified quantity and thereafter moving up the discharge tray until a top-surface detection part outputs a top-surface detection signal, while clocking a move-up time lasting from a move-up start of the discharge tray until output of the top-surface detection signal by the top-surface detection part. When the move-up time is equal to or less than a reference time, the sheet discharge device makes a next sheet discharged while the top-surface detection part outputs the top-surface detection signal; on the other hand, when the move-up time is more than the reference time, the sheet discharge device executes a correction process of moving down the discharge tray before making the next sheet discharged.

When a discharge count has exceeded a specified number of sheets, a sheet discharge device executes a process of moving down a discharge tray by a specified quantity and thereafter moving up the discharge tray until a top-surface detection part outputs a top-surface detection signal, while clocking a move-up time lasting from a move-up start of the discharge tray until output of the top-surface detection signal by the top-surface detection part. When the move-up time is equal to or less than a reference time, the sheet discharge device makes a next sheet discharged while the top-surface detection part outputs the top-surface detection signal; on the other hand, when the move-up time is more than the reference time, the sheet discharge device executes a correction process of moving down the discharge tray before making the next sheet discharged.

A post-processing apparatus includes a tray receiving an ejected recording medium, a moving mechanism vertically moving the tray, a driving source driving the moving mechanism, a member pressing, from vertically above, a recording medium ejected to the tray, a rotational-driving mechanism driving the member so that the member rotates in a first direction away from an apparatus body when the tray is moved upward by the moving mechanism and that the member rotates in a second direction toward the apparatus body when the tray is moved downward by the moving mechanism, a rotation-angle limiting unit limiting a rotation angle of the member when the member is driven to rotate in the first direction and to rotate in the second direction, and a rotational-force limiting mechanism idling when a rotational force not lower than a predetermined force is applied to the rotational-driving mechanism.