This invention provides a stacker for use in forming stacks of cut sheets received from an upstream utilization device (e.g. a printer, cutter, etc.) that allows for positive driving of sheets into a stack using a stacking unit that includes a series of grippers that are adapted to grip and release a leading edge of each sheet at the appropriate time. In this manner, each sheet is gripped as it arrives from the upstream operation and is passed downstream into the stack, being released so as to properly decelerate at the stack's backstop. The grippers are mounted on a continuous belt between a pair of opposing drive sprockets. An edge sensor located upstream of the stacking unit triggers motion of the belts. The grippers are actuated by a mechanical cam arrangement to selectively grip and release at predetermined positions as the belt is driven.

A trolley device is used to convey laminar elements. The trolley device includes at least one belt that defines a closed loop, a plurality of pulleys, at least one drive pulley being configured to act on the belt, the pulleys being mounted on a frame with a supporting region over which a section of the belt can be slid and wherein suction means linked to the belt are provided. The belt includes at least on the outer face thereof a projecting section of predetermined length that protrudes in height with respect to the rest of the belt, the projecting section being provided with a plurality of through holes aligned in position with through holes made in the belt.

An image forming apparatus comprises a first conveyance unit, an image forming unit, a second conveyance unit, a stacking unit, and a control unit. The control unit controls, in a case where a sheet stacking condition of the stacking unit does not satisfy a predetermined stacking condition, the second conveyance unit to convey the sheet at a second conveyance speed that is faster than the first conveyance speed. The control unit controls, in a case where the sheet stacking condition of the stacking unit satisfies the predetermined stacking condition, the second conveyance unit to convey the sheet at a third conveyance speed that is slower than the second conveyance speed.

A delivery system is used for delivering printed sheets which can be fed in a region of an inlet side of a delivery device. The delivery device includes at least one first discharge station and one second discharge station which is mounted downstream of the first discharge station, which is upstream in the transport path. The delivery stations are associated respectively with a format or transport-relevant device which can be controlled by a drive including a control element for adapting or correcting the guiding and delivery of the sheets in the relevant discharge station. At a delivery device level upstream of a lateral inlet in a stacking space of the upstream second discharge station, at least one operator interface, with at least one actuating device is provided. The at least one actuating device can be permanently connected to a signal or can be activated by an additional actuating device, with the control element of the at least one format- or transport-relevant device of the first discharge station and which allows or which can allow, during actuation, the control element of the system of the first discharge station which can vary with regard to the format- or transport-relevant size format, to be controlled.

During the operation of a delivery device, having a first and a second stack delivery, in a transport direction, in which a first braking device is provided in the transport path of sheets which are conveyed by a conveyor system along a transport path in the entry region of the first stack delivery, and in which a second braking device is provided in the input area of the second stack delivery, the sheets to be printed, which come into the first braking device come in a form- or friction-locking operative contact with an active surface of a holding means comprised by the braking device. The active surface coming into this operative contact with the sheet to be printed is moved forcibly by a drive in the transport direction. In a first operating mode, during a form- or friction-fit interaction between the sheet and the active surface, a speed for the movement of the active surface is reduced from a first speed to a comparatively lower stacking speed. The first braking device is operated in a second operating mode for a subsequently incoming sheet that is to be deposited on a stack of the second stack delivery. The active surface is moved, for at least the entire duration of the existing form- or friction-fit operating contact, with a speed between the respect sheet and the active surface. That speed corresponds approximately, i.e. with a deviation of 10%, to the conveying speed of the conveyor system.

An image forming apparatus comprises a first conveyance unit, an image forming unit, a second conveyance unit, a stacking unit, and a control unit. The control unit controls, in a case where a sheet stacking condition of the stacking unit does not satisfy a predetermined stacking condition, the second conveyance unit to convey the sheet at a second conveyance speed that is faster than the first conveyance speed. The control unit controls, in a case where the sheet stacking condition of the stacking unit satisfies the predetermined stacking condition, the second conveyance unit to convey the sheet at a third conveyance speed that is slower than the second conveyance speed.

A delivery system is used for delivering printed sheets which can be fed in a region of an inlet side of a delivery device. The delivery device includes at least one first discharge station and one second discharge station which is mounted downstream of the first discharge station, which is upstream in the transport path. The delivery stations are associated respectively with a format or transport-relevant device which can be controlled by a drive including a control element for adapting or correcting the guiding and delivery of the sheets in the relevant discharge station. At a delivery device level upstream of a lateral inlet in a stacking space of the upstream second discharge station, at least one operator interface, with at least one actuating device is provided. The at least one actuating device can be permanently connected to a signal or can be activated by an additional actuating device, with the control element of the at least one format- or transport-relevant device of the first discharge station and which allows or which can allow, during actuation, the control element of the system of the first discharge station which can vary with regard to the format- or transport-relevant size format, to be controlled.

During the operation of a delivery device, having a first and a second stack delivery, in a transport direction, in which a first braking device is provided in the transport path of sheets which are conveyed by a conveyor system along a transport path in the entry region of the first stack delivery, and in which a second braking device is provided in the input area of the second stack delivery, the sheets to be printed, which come into the first braking device come in in a form- or friction-locking operative contact with an active surface of a holding means comprised by the braking device. The active surface coming into this operative contact with the sheet to be printed is moved forcibly by a drive in the transport direction. In a first operating mode, during a form- or friction-fit interaction between the sheet and the active surface, a speed for the movement of the active surface is reduced from a first speed to a comparatively lower stacking speed. The first braking device is operated in a second operating mode for a subsequently incoming sheet that is to be deposited on a stack of the second stack delivery. The active surface is moved, for at least the entire duration of the existing form- or friction-fit operating contact, with a speed between the respect sheet and the active surface. That speed corresponds approximately, i.e. with a deviation of 10%, to the conveying speed of the conveyor system.

A printing apparatus includes a printing unit, first and second conveyance units conveying a print medium, and a control unit performing reduction control to reduce an overlap amount between a preceding print medium and a succeeding print medium by using a speed difference. In a first case in which a trailing end of the preceding print medium and a leading end of the succeeding print medium are positioned in an interval between the first and second conveyance units, a conveying speed of the preceding print medium is set to a first speed. In a second case which is different from the first case and in which the trailing end and the leading end are positioned in the interval between the first and second conveyance units, the conveying speed of the preceding print medium is set to a second speed different from the first speed.

This invention provides a stacker for use in forming stacks of cut sheets received from an upstream utilization device (e.g. a printer, cutter, etc.) that allows for positive driving of sheets into a stack using a stacking unit that includes a series of grippers that are adapted to grip and release a leading edge of each sheet at the appropriate time. In this manner, each sheet is gripped as it arrives from the upstream operation and is passed downstream into the stack, being released so as to properly decelerate at the stack's backstop. The grippers are mounted on a continuous belt between a pair of opposing drive sprockets. An edge sensor located upstream of the stacking unit triggers motion of the belts. The grippers are actuated by a mechanical cam arrangement to selectively grip and release at predetermined positions as the belt is driven.