Abstract: There are provided a sheet processing apparatus which can perform a punching process while suppressing decrease in productivity, and an image forming apparatus including the sheet processing apparatus. In a third carry-in route R3 branching from a first carry-in route, a discharge roller and a buffer roller convey a sheet for which the punching process has been performed by a punching unit, so that an upstream end in a sheet conveyance direction of the sheet for which the punching process has been performed precedes an upstream end in the sheet conveyance direction of a succeeding sheet following the sheet for which the punching process has been performed.

Abstract: A sheet cutting apparatus, including: a conveying member configured to convey a half-folded sheet bunch in a conveyance path in which the conveying member is provided; a registration member which comes into contact with a leading edge portion of the sheet bunch to correct a skew feed of the sheet bunch; a cutting member positioned upstream of the registration member to cut a trailing edge portion of the sheet bunch; and a discharging member provided at an outlet of the conveyance path to discharge the sheet bunch, wherein the leading edge portion of the sheet bunch is positioned outside the discharging member when, after the skew feed is corrected, the sheet bunch is conveyed downstream in the conveying direction by the conveying member and the trailing edge portion of the sheet bunch is conveyed to a cutting position of the cutting member to cut the trailing edge portion.

Abstract: In order to stack a larger number of sheets on trays by reducing a total thickness of the trays and enabling the trays to ascend and descend actually over long distances, a sheet stacking device includes an upper-tray and a lower-tray which are ascendible and descendible and on which sheets delivered from a delivery roller pair are stacked, a motor and a belt for allowing both the trays to ascend and descend, a clutch for disconnecting the upper-tray and the belt from each other, and a claw and a rack for stopping self-weight descent of the upper-tray when the clutch effects the disconnection. A clearance between the upper-tray under the disconnection by the clutch and in the stop of the self-weight descent by the claw engaged with the rack and the lower-tray connected to the belt is adjustable by ascent and descent of the lower-tray by the motor.

Abstract: There are provided a sheet processing apparatus which can perform a punching process while suppressing decrease in productivity, and an image forming apparatus including the sheet processing apparatus. In a third carry-in route R3 branching from a first carry-in route, a discharge roller and a buffer roller convey a sheet for which the punching process has been performed by a punching unit, so that an upstream end in a sheet conveyance direction of the sheet for which the punching process has been performed precedes an upstream end in the sheet conveyance direction of a succeeding sheet following the sheet for which the punching process has been performed.

Abstract: In order to stack a larger number of sheets on trays by reducing a total thickness of the trays and enabling the trays to ascend and descend actually over long distances, a sheet stacking device includes an upper-tray and a lower-tray which are ascendible and descendible and on which sheets delivered from a delivery roller pair are stacked, a motor and a belt for allowing both the trays to ascend and descend, a clutch for disconnecting the upper-tray and the belt from each other, and a claw and a rack for stopping self-weight descent of the upper-tray when the clutch effects the disconnection. A clearance between the upper-tray under the disconnection by the clutch and in the stop of the self-weight descent by the claw engaged with the rack and the lower-tray connected to the belt is adjustable by ascent and descent of the lower-tray by the motor.

Abstract: A sheet cutting apparatus, including: a conveying member configured to convey a half-folded sheet bunch in a conveyance path in which the conveying member is provided; a registration member which comes into contact with a leading edge portion of the sheet bunch to correct a skew feed of the sheet bunch; a cutting member positioned upstream of the registration member to cut a trailing edge portion of the sheet bunch; and a discharging member provided at an outlet of the conveyance path to discharge the sheet bunch, wherein the leading edge portion of the sheet bunch is positioned outside the discharging member when, after the skew feed is corrected, the sheet bunch is conveyed downstream in the conveying direction by the conveying member and the trailing edge portion of the sheet bunch is conveyed to a cutting position of the cutting member to cut the trailing edge portion.