A medium conveyance route switching device includes: a support unit located at a branching point where conveyance directions of a medium converge in three directions; a gate assembly including a plurality of gates to guide at the branching point the medium to different conveyance paths; and a rotation mechanism configured to selectively rotate the plurality of gates. The support unit includes: a first support piece having a first through-hole portion; a second support piece having a second through-hole portion; a third support piece having a third through-hole portion; a first bending connection portion rotatably connecting one end of the first support piece and the second support piece; a second bending connection portion rotatably connecting the other end of the first support piece and the third support piece; and a fixing shaft inserted into the first through-hole portion, the second through-hole portion, and the third through-hole portion.

A sheet sorting apparatus includes a first tray detachable from an apparatus main body, a second tray arranged below the first tray, a discharge unit to discharge a sheet to the first or second tray, a tray detecting unit to detect that the first tray is detached from the apparatus main body, a full stack detecting unit to detect a fully stacked condition of the first tray, and a control unit to control the discharge unit. In a case where the tray detecting unit detects that the first tray is detached from the apparatus main body, the control unit controls the discharge unit not to discharge a sheet to the second tray when a number of sheets discharged to the second tray reaches a threshold number of sheets, even though the full stack detecting unit does not detect the fully stacked condition.

A sheet sorting apparatus includes a first tray detachable from an apparatus main body, a second tray arranged below the first tray, a discharge unit to discharge a sheet to the first or second tray, a tray detecting unit to detect that the first tray is detached from the apparatus main body, a full stack detecting unit to detect a fully stacked condition of the first tray, and a control unit to control the discharge unit. In a case where the tray detecting unit detects that the first tray is detached from the apparatus main body, the control unit controls the discharge unit not to discharge a sheet to the second tray when a number of sheets discharged to the second tray reaches a threshold number of sheets, even though the full stack detecting unit does not detect the fully stacked condition.

A sheet post-processing device includes a folding portion, a discharge portion, a stacking tray, a shift unit, a pair of alignment members, and a controller. The pair of alignment members include first and second alignment members at one and the other side of sheets stacked on the stacking tray. When a sheet bundle sorted and stacked on the stacking tray includes a folded sheet, executes a second alignment mode in which it performs, for sheets shifted to a first position at one side on the stacking tray, alignment with only the first alignment member and, for sheets shifted to a second position at the other side, alignment with only the second alignment member, or does not perform alignment process.

A sheet post-processing device includes a folding portion, a discharge portion, a stacking tray, a shift unit, a pair of alignment members, and a controller. The pair of alignment members include first and second alignment members at one and the other side of sheets stacked on the stacking tray. When a sheet bundle sorted and stacked on the stacking tray includes a folded sheet, executes a second alignment mode in which it performs, for sheets shifted to a first position at one side on the stacking tray, alignment with only the first alignment member and, for sheets shifted to a second position at the other side, alignment with only the second alignment member, or does not perform alignment process.

A medium passage switching mechanism disposed on a casing of an image forming device, includes a medium tray, a guiding component and a resilient 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 and can pivot between a first position and a second position. The guiding component is pivoted to the casing and can pivot between a third position and a fourth position. The resilient component abuts against the guiding component and the casing. When the medium tray pivots between the first position and the second position, the guiding component can be driven by cooperation of the resilient component and the medium tray to pivot between the third position and the fourth position for guiding a medium to enter into the first exit passage or the second exit passage 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 resilient 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 and can pivot between a first position and a second position. The guiding component is pivoted to the casing and can pivot between a third position and a fourth position. The resilient component abuts against the guiding component and the casing. When the medium tray pivots between the first position and the second position, the guiding component can be driven by cooperation of the resilient component and the medium tray to pivot between the third position and the fourth position for guiding a medium to enter into the first exit passage or the second exit passage from the entrance passage.

A sheet processing apparatus includes a buffering portion having a reverse conveyance roller pair and an intermediate roller pair, with the reverse conveyance roller pair reversing a conveyance direction of a sheet received from a first conveyance path and delivering the reversed sheet into a second conveyance path and being configured to come into contact with and be separated from each other. The intermediate roller pair is disposed in the second conveyance path and disposed upstream of a conveyance roller pair in a sheet conveyance direction, and the reverse conveyance roller pair is caused to nip a first sheet and a second sheet by causing the reverse conveyance roller pair to abut each other after receiving the second sheet by the reverse conveyance roller pair from the first conveyance path in a state in which the intermediate roller pair nips the first sheet reversed by the reverse conveyance roller pair and the reverse conveyance roller pair is separated from each other.

A sheet conveyance device capable of reducing occurrence of creases on a sheet. A pair of first conveyance rollers nip and convey a sheet. A pair of second conveyance rollers arranged downstream of the first conveyance rollers in a sheet conveyance direction nip and convey the sheet. A pair of registration rollers arranged downstream of the second conveyance rollers nip and convey the sheet after correcting skew of the sheet. A switching mechanism switches a state of the second conveyance rollers between a contact state and a separated state. A control unit that controls the rollers and the switching mechanism executes a first conveyance operation that conveys the sheet with the first conveyance rollers and the registration rollers after correcting the skew in the separated state and in a state where a sheet conveyance speed by the registration rollers is higher than that by the first conveyance rollers.

A sheet conveyance device capable of reducing occurrence of creases on a sheet. A pair of first conveyance rollers nip and convey a sheet. A pair of second conveyance rollers arranged downstream of the first conveyance rollers in a sheet conveyance direction nip and convey the sheet. A pair of registration rollers arranged downstream of the second conveyance rollers nip and convey the sheet after correcting skew of the sheet. A switching mechanism switches a state of the second conveyance rollers between a contact state and a separated state. A control unit that controls the rollers and the switching mechanism executes a first conveyance operation that conveys the sheet with the first conveyance rollers and the registration rollers after correcting the skew in the separated state and in a state where a sheet conveyance speed by the registration rollers is higher than that by the first conveyance rollers.