In an example printing device may include a tray to receive print media sheets, and a paddle roller to rotate about an axis and move individual print media sheets of the print media sheets to abut an end register of the tray and form a stack of print media sheets, and the paddle roller rotate a first quantity of rotations per print media sheet based in response to a determination that the stack of print media sheets corresponds to a first height.

A sheet processing machine stores sheets transported by a transport unit. The sheet processing machine includes: a reel on which a first end side of a tape is wound; a first stepper motor that rotates the reel about a rotation axis of the reel; a drum configured to wind up a second end side of the tape together with the sheets to form a winding body together with the tape and the sheets; a second stepper motor that rotates the drum about a rotation axis of the drum; and circuitry configured to change an interval between the sheets wound on the drum by controlling a rotation of the first stepper motor and the second stepper motor based on a parameter indicating a condition of the winding body.

In an example printing device may include a tray to receive print media sheets, and a paddle roller to rotate about an axis and move individual print media sheets of the print media sheets to abut an end register of the tray and form a stack of print media sheets, and the paddle roller rotate a first quantity of rotations per print media sheet based in response to a determination that the stack of print media sheets corresponds to a first height.

A sheet processing apparatus includes a puncher, a first sensor positioned upstream of the puncher in the conveyance direction, a second sensor positioned upstream of the first detection position in the conveyance direction, a drive source configured to drive the puncher, a controller configured to control the drive source. The controller executes a control mode including a first process of controlling a rotation speed of the puncher on a basis of a detection result of the second sensor and a second process of controlling the rotation speed of the puncher on a basis of a detection result of the first sensor. In the control mode, the controller does not stop rotation of the puncher in a period between the punching process on the preceding sheet and a punching process on the succeeding sheet.

A sheet conveying apparatus includes a sheet conveying path, conveying members, a switching unit, a receiving unit, and a control unit. The sheet conveying path includes a first conveying path and a second conveying path having a conveying load for a sheet larger than the first conveying path. The switching unit selectively switches the sheet conveying path between the first conveying path and the second conveying path. The control unit determines whether the sheets are first sheets or second sheets thicker than the first sheets, based on sheet thickness information received by the receiving unit. If the sheets are the first sheets, the switching unit switches the sheet conveying path between the first conveying path and the second conveying path alternately. If the sheets are the second sheets, the switching unit switches to fix the sheet conveying path to the first conveying path.

A sheet processing apparatus includes a puncher, a first sensor positioned upstream of the puncher in the conveyance direction, a second sensor positioned upstream of the first detection position in the conveyance direction, a drive source configured to drive the puncher, a controller configured to control the drive source. The controller executes a control mode including a first process of controlling a rotation speed of the puncher on a basis of a detection result of the second sensor and a second process of controlling the rotation speed of the puncher on a basis of a detection result of the first sensor. In the control mode, the controller does not stop rotation of the puncher in a period between the punching process on the preceding sheet and a punching process on the succeeding sheet.

A sheet stacking device is provided with a hopper unit configured to stack a sheet, a feeding unit configured to feed out the sheet to the hopper unit, a distance detection unit configured to detect an inter-sheet distance, in the vertical direction, between a rear end portion of the sheet that is preceding and a tip end portion of the sheet that is subsequent, and an output unit configured to output a behavior stabilization command for the sheet based on the inter-sheet distance.

The relay conveyance device includes a relay conveyance path, a plurality of conveyance members, at least one detection member and a control device. The control device executes a correction processing such that, in a state where a first sheet and a second sheet positioned at the upstream side from the first sheet are conveyed along the relay conveyance path, a sheet interval from a detection end of the first sheet by the detection member to a detection start of the second sheet by the detection member is compared with a predetermined target value, when the sheet interval is smaller than the target value, the conveyance speed of the conveyance member is decreased so as to widen the sheet interval, and when the sheet interval is larger than the target value, the conveyance speed of the conveyance member is increased so as to shorten the sheet interval.

A sheet processing machine stores sheets transported by a transport unit. The sheet processing machine includes: a reel on which a first end side of a tape is wound; a first stepper motor that rotates the reel about a rotation axis of the reel; a drum configured to wind up a second end side of the tape together with the sheets to form a winding body together with the tape and the sheets; a second stepper motor that rotates the drum about a rotation axis of the drum; and circuitry configured to change an interval between the sheets wound on the drum by controlling a rotation of the first stepper motor and the second stepper motor based on a parameter indicating a condition of the winding body.

A relay conveyance device includes a relay conveyance path arranged between an image forming apparatus and a post processing device to convey a sheet from the image forming apparatus to the post processing device, two reversing units reversing a surface side and a back-face side of the sheet, and a control device controlling conveyance of the sheet on the relay conveyance path. The relay conveyance path includes two reverse paths respectively passing through the two reversing units, a branch section branching into the two reverse paths at an upstream side, and a confluence section joining the two reverse paths. The control device controls the branch and confluence sections to convey the sheet while alternately switching the two reverse paths, measures an interval time between the sheets passing through the confluence section, and controls conveyance of the sheet in the two reverse paths so as to uniformize the interval time.