Device for stacking of sheets

Device according to any preceding claim for transporting sheets (2) in a plant (1) in which a high-speed printer (6) is included for printing said sheets (2) or at least one continuous web (5) which is cut into sheets (2),

• said transport device (9) being provided to transport the sheets (2) in at least one flow (AS1 and/or AS2) thereof or at least one continuous web (5),
• wherein the transport device (9) includes at least one vacuum means (9b) with at least one vacuum opening (9c, 9d) which communicates with vacuum holes (9e) in at least one conveyor belt (9a), and
• wherein a vacuum generating device (VA) is provided to generate a vacuum in the vacuum opening (9c, 9d) of the vacuum means (9b) such that said conveyor belt (9a) can engage and transport the sheets (2),
• characterized in
• that the vacuum generating device (VA) comprises a compressed-air generating device (9f) from which compressed air is fed or supplied to at least one ejector (9g) such that a jet (D) of compressed air therein generates a vacuum in the vacuum opening (9c, 9d) in the vacuum means (9b) and in the vacuum holes (9e) in the conveyor belts (9a).

Device according to any preceding claim,

• wherein a device (10) for lateral movement of sheets (2) is provided such that the sheets (2) or stacks (2A, 2B) of sheets (2) occupy laterally displaced positions relative to each other in the stacking device (11) when they are located on top of each other in a stacking device (11),
• wherein the device comprises at least one pair of conveyor belts (14) which are diverging relative to a main transport direction (A) such that they can move sheets (2) laterally in different lateral directions (B, C) relative to said main transport direction (A), and
• wherein a gripping and contact maintaining appliance is provided such that the conveyor belts (14) can grip or engage sheets (2) and hold them in contact with said conveyor belts (14) for transport thereby,
• characterized in
• that said gripping and contact maintaining device is a vacuum generating device (V) having vacuum means (12, 13) with vacuum openings (17, 18, 19) located within vacuum holes (20) in the conveyor belts (14), and provided to generate a vacuum in said vacuum openings (17, 18, 19) and vacuum holes (20) so that said conveyor belts (14) can grip or engage and transport the sheets (2), and
• that a device for determining which conveyor belt (14) of the two vacuum means (12, 13) that shall transport the sheets (2), is a vacuum control device (30) which controls the vacuum generating device (V) to alternatingly either generate a vacuum in at least one vacuum opening (17, 18, 19) in one of the vacuum means (12) or in at least one vacuum opening (17, 18, 19) in the other vacuum means (13) such that one or more sheets (2) is/are engaged and transported or fed by one or the other conveyor belt (14) of said vacuum means (12, 13).

Device according to any preceding claim,

• wherein the transport device (9) is provided to transport sheets (2) in at least two flows (AS1, AS2) thereof,
• wherein conveyor belts (14) in a first pair (TB1) thereof are provided to laterally move sheets (2) in one flow (AS1) of sheets and conveyor belts (14) in a second pair (TB2) thereof are provided to laterally move sheets (2) in the other flow (AS2) of sheets, and
• wherein the conveyor belts (14) in each pair (TB1 and TB2 respectively) thereof are mounted such that an angle between each conveyor belt (14) and a centre line (CL) between the conveyor belts is the same or substantially the same,
• characterized in
• that the pairs (TB1, TB2) of conveyor belts are located relative to each other such that their centre lines (CL), seen in the main transport direction (A), diverge for providing groups of stacks located beside each other.