A post-processing apparatus includes a conveyance unit, a discharge port, a tray, an elevation unit, a detection unit, and a control unit. The conveyance unit conveys a print medium supplied from an image forming apparatus. The discharge port discharges the print medium conveyed by the conveyance unit. The tray is stacked with the print medium discharged from the discharge port and can be raised and lowered in a vertical direction. The elevation unit raises and lower the tray in the vertical direction. The detection unit detects a top surface of an uppermost print medium of one or more sheets of print media stacked on the tray. The control unit controls the conveyance unit and the elevation unit and hold a relative position of the top surface with respect to the discharge port if the print medium is discharged from the discharge port at a first position. The control unit causes the conveyance unit to convey the print medium at a first speed if a discharge time from a first timing indicating the timing relating to discharge of the print medium from the discharge port to a second timing indicating the timing when the print medium is detected by the detection unit is a first time and causes the conveyance unit to convey the print medium at a second speed different from the first speed if the discharge time is a second time.

A post-processing apparatus includes a conveyance unit, a discharge port, a tray, an elevation unit, a detection unit, and a control unit. The conveyance unit conveys a print medium supplied from an image forming apparatus. The discharge port discharges the print medium conveyed by the conveyance unit. The tray is stacked with the print medium discharged from the discharge port and can be raised and lowered in a vertical direction. The elevation unit raises and lower the tray in the vertical direction. The detection unit detects a top surface of an uppermost print medium of one or more sheets of print media stacked on the tray. The control unit controls the conveyance unit and the elevation unit and hold a relative position of the top surface with respect to the discharge port if the print medium is discharged from the discharge port at a first position. The control unit causes the conveyance unit to convey the print medium at a first speed if a discharge time from a first timing indicating the timing relating to discharge of the print medium from the discharge port to a second timing indicating the timing when the print medium is detected by the detection unit is a first time and causes the conveyance unit to convey the print medium at a second speed different from the first speed if the discharge time is a second time.

In some examples, a sheet processing machine includes at least one transport means of an infeed system, and the infeed system includes at least one cam mechanism including, in each case, at least one cam disk having an axis of rotation. At least one scanning element is arranged in each case to rest against the at least one cam disk. The at least one scanning element is connected to the at least one transport means via at least one drive lever. The at least one drive lever in each case has at least one mounting point. The mounting point and the axis of rotation may be adjusted relative to one another, and a position displacement of the mounting point relative to the axis of rotation may compensate for at least one position error of the at least one sheet.

In some examples, a sheet processing machine includes at least one transport means of an infeed system, and the infeed system includes at least one cam mechanism including, in each case, at least one cam disk having an axis of rotation. At least one scanning element is arranged in each case to rest against the at least one cam disk. The at least one scanning element is connected to the at least one transport means via at least one drive lever. The at least one drive lever in each case has at least one mounting point. The mounting point and the axis of rotation may be adjusted relative to one another, and a position displacement of the mounting point relative to the axis of rotation may compensate for at least one position error of the at least one sheet.

A sheet transport device includes a transport guide for guiding, along its transport surface, a sheet in a transport direction, a first transport roller pair, a second transport roller pair, a skew roller pair, a reference wall, and an actuator. The skew roller pair alone transports, in a skewed manner toward an end of the transport surface in a width direction orthogonal to the transport direction, the sheet spaced from the first transport roller and the second transport roller. The reference wall is positioned at the end of the transport surface in the width direction and extends along the transport direction. The actuator is disposed downstream of the skew roller pair and upstream of the second transport roller pair in the transport direction and between the end and a center of the transport surface in the width direction.

A sheet transport device includes a transport guide for guiding, along its transport surface, a sheet in a transport direction, a first transport roller pair, a second transport roller pair, a skew roller pair, a reference wall, and an actuator. The skew roller pair alone transports, in a skewed manner toward an end of the transport surface in a width direction orthogonal to the transport direction, the sheet spaced from the first transport roller and the second transport roller. The reference wall is positioned at the end of the transport surface in the width direction and extends along the transport direction. The actuator is disposed downstream of the skew roller pair and upstream of the second transport roller pair in the transport direction and between the end and a center of the transport surface in the width direction.

An inkjet printing machine for printing individual sheets comprises at least one printing station and a transport system defining a transport track for transporting the individual sheets through the printing station, along a transport direction. The transport system comprises a plurality of gripper conveyors (150) running along the transport track for holding the individual sheets during a printing process in the printing station. Each of the gripper conveyors (150) comprises an energy storage (161) for providing energy for operating a gripper mechanism (171) of the gripper conveyor (150). The printing machine allows for efficient and flexible handling of individual sheets, in particular large format sheets of materials such as corrugated cardboard or other materials that have a certain degree of inherent stability.

An inkjet printing machine for printing individual sheets comprises at least one printing station and a transport system defining a transport track for transporting the individual sheets through the printing station, along a transport direction. The transport system comprises a plurality of gripper conveyors (150) running along the transport track for holding the individual sheets during a printing process in the printing station. Each of the gripper conveyors (150) comprises an energy storage (161) for providing energy for operating a gripper mechanism (171) of the gripper conveyor (150). The printing machine allows for efficient and flexible handling of individual sheets, in particular large format sheets of materials such as corrugated cardboard or other materials that have a certain degree of inherent stability.

A sheet feeding device includes a sensor, a roller, and a support on which the sensor and the roller are disposed. The support supports the sensor and the roller so that the sensor and the roller contact a surface of the sheet roll. The sensor and the roller face toward an axial center of the sheet roll. The roller is spaced apart from the sensor in a circumferential direction of the sheet roll. The sensor has a detection accuracy capable of detecting a step at a leading end of the sheet roll.

A sheet feeding device includes a sensor, a roller, and a support on which the sensor and the roller are disposed. The support supports the sensor and the roller so that the sensor and the roller contact a surface of the sheet roll. The sensor and the roller face toward an axial center of the sheet roll. The roller is spaced apart from the sensor in a circumferential direction of the sheet roll. The sensor has a detection accuracy capable of detecting a step at a leading end of the sheet roll.