Arrangement and method for handling paper elements

Abstract

An arrangement (100) for handling flat elements (202), in particular paper elements (202). A guiding structure (101) is provided, along which a flat element (202) is guidable and transportable along a transport direction (T). A hold-down element (102) is coupled to the guiding structure (101) for holding down the flat element (202) to the guiding structure (101). The hold-down element (102) has a support section (103) on which the flat element (202) is supportable. The hold-down element (102) extends along an extending direction (116) having a component perpendicular to the transport direction (T), wherein suction holes (104) are arranged along the extending direction (116). A suction unit (110) includes a suction opening (111) coupled to the suction holes (104) of the hold-down element (102), an air inlet (112) and an air outlet (113), wherein the suction unit (110) directs air from the air inlet (112) to the air outlet (113) for generating an air flow (114). The suction opening (111) is formed and arranged such that the air flow (114) passes the suction opening (111) so that air flow (114) entrains air through the suction opening (111).

Claims

1. An arrangement for handling flat elements, the arrangement comprising: a guiding structure along which a flat element is guidable and transportable along a transport direction (T), a hold-down element which is coupled to the guiding structure and located and configured for holding the flat element down to the guiding structure, the hold-down element comprises a support section on which the flat element is supportable, wherein the support section comprises suction holes through which air is drawn for holding the flat element on the support section, wherein the hold-down element extends along an extending direction having a component perpendicular to the transport direction (T), wherein the suction holes are arranged along the extending direction, a suction unit comprising a suction opening configured to be coupled to the suction holes of the hold-down element, wherein the suction unit is separate from and spaced apart from the hold-down element, the suction unit having an air inlet and an air outlet, the suction unit is configured such that air is directed from the air inlet to the air outlet for generating an air flow, and the suction opening is formed and arranged such that the air flow passes the suction opening such that the passing air flow entrains air through the suction opening.

2. The arrangement according to claim 1, further comprising: a compressed air connection element coupled to the air inlet of the suction unit, wherein the compressed air connection element is formed to be connectable to an external pressurized air source.

3. The arrangement according to claim 1, further comprising: a supporting frame, configured for and having the hold-down element mounted to the supporting frame in an exchangeable manner for the hold down element.

4. The arrangement according to claim 3, wherein the hold-down element is mounted to the supporting frame such that the hold-down element is adjustable along the transport direction (T).

5. The arrangement according to claim 3, wherein the hold-down element is movable with respect to the supporting frame between an active position where the hold down element is located and configured for holding the flat element down and an inactive position at which the flat element is movable for passing the support section of the hold-down element.

6. The arrangement according to claim 5, wherein the hold-down element is configured to be rotatable such that the hold-down element is rotatable between the active position and the inactive position.

7. The arrangement according to claim 6, further comprising: a connection tube which couples the through holes of the hold-down element to the suction opening of the suction unit.

8. The arrangement according to claim 7, wherein the support section comprises an edge extending along the extending direction, and the support section has a total width (w) defined along the extending direction, and wherein each of the suction holes is arranged spaced apart from the edge at a distance of , or 1/10 of the total width (w) of the support section.

9. A system for processing flat elements, the system comprising: a processing device for processing flat elements, and an arrangement according to claim 1, wherein the guiding structure of the arrangement is coupled to the processing device such that the flat elements are guidable and transportable along a transport direction (T) to or from the processing device.

10. A system according to claim 9, wherein the processing device is selected from one of the group consisting of paper cutting machines, paper printing machines, feeding machines and paper stripping machines.

11. The arrangement according to claim 1, wherein the guiding structure for the flat element has a level and the support section at the suction holes is at the level of the guiding structure.

12. The arrangement according to claim 1, further comprising a processing device for processing a flat element, the processing device being located downstream from the support structure in the transport direction by a distance selected such that when a flat element leading end in the transport direction is transported to be at the processing device, a trailing end of the flat element is at the suction holes.

13. The arrangement according to claim 1, wherein the support section further comprises a connection tube configured to conduct air let in through the suction holes to a first point outside of the hold-down element, and the suction opening of the suction unit is coupled to the first point of the connection tube of the hold-down element.

14. A method for handling flat elements, the method comprising: guiding and transporting a flat element along a transport direction (T) by a guiding structure, holding the flat element to the guiding structure by a hold-down element, which is coupled to the guiding structure, wherein the hold-down element comprises a support section on which the flat element is supported, the support section comprises suction holes through which air is drawn for holding the flat element on the support section, wherein the hold-down element extends along an extending direction having a component perpendicular to the transport direction (T), wherein the suction holes are arranged along the extending direction, wherein a suction unit comprises a suction opening configured to be coupled to the suction holes of the hold-down element, wherein the suction unit is separate from and spaced apart from the hold-down element; wherein the suction unit is directing air from an air inlet of the suction unit to an air outlet of the suction unit for generating an air flow between the air inlet and the air outlet, wherein the suction opening is configured and arranged such that the air passes the suction opening so that the air passing the suction opening entrains air through the suction opening.

15. The method according to claim 14, wherein the support section further comprises a connection tube configured to conduct air let in through the suction holes to a first point outside of the hold-down element, and the suction opening of the suction unit is coupled to the first point of the connection tube of the hold-down element.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) The aspects defined above and further aspects of the present invention are apparent from the examples of embodiments described hereinafter and are explained with reference to the examples of embodiment. The invention will be described in more detail hereinafter with reference to examples of embodiments but to which the invention is not limited.

(2) FIG. 1 shows a schematic view of an arrangement for handling flat elements according to an exemplary embodiment of the present invention.

(3) FIG. 2 shows a schematic view of a system for processing flat elements and of a building system according to an exemplary embodiment of the present invention.

(4) FIG. 3 shows a schematic view of a suction unit according to an exemplary embodiment of the present invention.

(5) FIG. 4 and FIG. 5 respectively show schematic views of a top view and a side view of the arrangements for handling elements, wherein the hold-down element is rotatable according to an exemplary embodiment of the present invention.

(6) FIG. 6 and FIG. 7 respectively show schematic side views of a system for processing flat elements, wherein a gripper bar device moves the flat elements to a stack of flat elements according to an exemplary embodiment of the present invention.

(7) FIG. 8 shows a schematic view of an arrangement for handling flat elements according to an exemplary embodiment of the present invention in which two or more suction units are employed.

DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS

(8) The illustrations in the drawings are schematic. It is noted that in different figures similar or identical elements are provided with the same reference signs.

(9) FIG. 1 shows an arrangement 100 for handling flat elements 202, in particular paper elements 202, according to an exemplary embodiment of the present invention. A guiding structure 101 is provided, along which a flat element 202 is guidable and transportable along a transport direction T. A hold-down element 102 is coupled to the guiding structure 101 for holding the flat element 202 down to the guiding structure 101, wherein the hold-down element 102 comprises a support section 103 on which the flat element 202 is supportable. The support section is at or near to the plane of the guiding structure 101 adjacent the support section. The support section 103 has suction holes 104 therethrough which air is drawn for holding the flat element 202 down on the support section 103. The hold-down element 102 extends along an extending direction 116 which in the exemplary embodiment is perpendicular to the transport direction T. The suction holes 104 are arranged one after another along the extending direction 116.

(10) A suction unit 110 is arranged spaced apart or remote from the hold-down element 102. The suction unit comprises a suction opening 111 so as to be coupled to the suction holes 104 of the hold-down element 102, an air inlet 112 and an air outlet 113, wherein the suction unit 110 is formed such that compressed air is directed from the air inlet 112 to the air outlet 113 for generating a compressed air stream 114. The suction opening 111 is formed and arranged such that the compressed air stream 114 passes the suction opening 111 so that compressed air stream 114 entrains air through the suction opening 111. A compressed air connection element 120 is coupled to the air inlet 112 of the suction unit 110, wherein the compressed air connection element 120 is formed so as to be connectable to an external pressurized air source 220.

(11) The flat elements may in the exemplary embodiment be example flat paper sheets 202 (see FIG. 2). For example, the flat elements 202 are sheet-like in shape and may be stackable on top of each other to form a stack of flat elements 202. The flat elements 202 are, for example, paper sheets made of a paper or a carton/cardboard structure.

(12) The transport direction T describes the direction of movement of the flat elements 202 during the processing of the flat elements 202. The transport direction T describes the direction of movement of the flat elements 202 along the sheet conveyance path when each element is passing the hold-down element 102.

(13) The guiding structure 101 comprises for example a support area 106 on which the flat elements 202 are supportable and are movable along the transport direction T. In particular, the hold-down element 102 is interposed upstream and downstream of the respective support areas 106 of the guiding structure 101 with respect to the transport direction T. Furthermore, the guiding structure 101 is fixed to a supporting frame 115, a ground and/or to a subsequent processing device, in particular, a paper processing device 210 (see FIG. 2) such that the flat elements 202 are guidable along the guiding structure 101 to the processing device 210. The guiding structure 101 may for example comprise a conveyor belt 201 or other transport rollers 107 on which the flat elements 202 are movable and guidable. As seen in FIG. 1, the supporting frame 115 may be formed of a framework made of bars or the like, for example.

(14) The hold-down element 102 is a beam comprising a rectangular cross-section. The hold-down element 102 is coupled to the guiding structure 101 permanently or removably. The hold-down element 102 comprises the support section 103 on which the flat element 202 is supportable by moving along the transport direction T. When passing the support section 103 of the hold-down element 102, the flat element 202 is held down to the support section 103 and for example fixed to the support section 103 such that a further movement of the flat elements 202 along the transport direction T is disabled or decelerated.

(15) The hold-down element 102 comprises the suction holes 104 through which air is drawn for holding the flat element 202 down on the support section 103. In particular, an underpressure is generated within the hold-down element 102, such that the air is drawn from the outside of the hold-down element 102 through the respective suction holes 104 into the hold-down element 102. The flat element 202 is thereby held down to the support section 103.

(16) In order to generate the underpressure within the hold-down element 102, the suction unit 110 is coupled by a suction opening 111 to the respective suction holes 104. A connection tube 108 may couple the hold-down element 102 to the suction opening 111 of the suction unit 110. A suction air stream is generated between the suction holes and the suction opening 111. An external pressurized air source 220 (see FIG. 2), such as an air pump and the like as described further in detail below, is coupled to the air inlet 112 of the suction unit 110. A compressed air stream 105 is thereby formed between the air inlet 112 and the air outlet 113 of the suction unit 110. That compressed air stream 114 passes the suction opening 111 to entrain the air from the suction holes 104 through the suction opening 111 for providing the underpressure within the hold-down element 102. A more detailed view of the suction unit 110 is shown in FIG. 3.

(17) The suction unit 110 is arranged spaced apart from the hold-down element 102 and is coupled e.g. by a connection tube 108 to the respective suction holes 104. Hence, the hold-down element 102 may be manufactured for example as a hollow bar comprising the suction holes 104 so that the hold-down element 102 is easy to install to the respective guiding structure 115. No further movable or other installations inside the hold-down element 102 are necessary for controlling the air flow through the suction holes 104 are necessary. Furthermore, the hold-down element 102 is free of any further technical installations.

(18) The hold-down element 102 comprises a plurality of suction holes 104 coupled to the suction opening 111 of the suction unit 110. In particular, the plurality of suction holes 104 is arranged one after another along a row, wherein the row extends along the extending direction 116 perpendicular to the transport direction T. However, in a further exemplary embodiment, further rows of suction holes 104 may also be arranged parallel to the above described row, for example.

(19) The hold-down element 102 is mounted to the supporting frame 115 in an exchangeable manner, for example for maintenance reasons. The hold-down element 102 is mounted to the supporting frame 115 to be adjustable along transport direction T. Hence, the location (i.e. the point of action) of the suction force with respect to an upstream or downstream (with respect to the transport direction T) located processing device 210 is adjustable.

(20) FIG. 2 shows a system 200 for processing flat elements 202, in particular paper elements 202. The system 200 comprises a (paper) processing device 210 for processing flat elements 202 and an arrangement 100 as shown in FIG. 1. The guiding structure 101 of the arrangement 100 is coupled to the (paper) processing device 210 in such a way that the flat elements 202 are guidable and transportable along the transport direction T and then from the (paper) processing device 210.

(21) Furthermore, a building system, i.e. a wall of a building 230 is shown. The building 230 comprises a pressurized air system comprising a pressurized air source 220 and a plurality of connection locations 221 which are coupled to the pressurized air source 220 for receiving pressurized air. The compressed air connection element 120 of the arrangement 100 is detachably coupled to one of the connection locations 221. The flexible and variable compressed air connection element 120 is coupled to the air inlet 112 of the suction unit 110.

(22) Furthermore, between the compressed air connection element 120 and the external pressurized air source 220, a connection tube 204 is arranged so that the distance between the compressed air connection element 120 and the external air source 220 is bridged.

(23) The paper processing device 210 is for example a paper cutting machine, a paper printing machine, a platen press, a feeding machine or a paper stripping machine. The arrangement 100, and in particular the guiding structure 101 with the hold-down element 102, is coupled upstream with respect to the transport direction T before the paper processing device 210. Hence, the arrangement 100 for handling flat elements 202 orients and holds the flat elements 202 in a predefined orientation such that an accurate and exact feeding of the respective paper element 202 into the subsequent paper processing device 210 is provided. The hold-down element 102 extends perpendicular to the transport direction T. The paper processing device 210 may comprise for example roller elements 203 for feeding the respective paper element 202 into the paper processing device 210.

(24) FIG. 3 shows a schematic view of a suction unit 110 according to an exemplary embodiment of the present invention. The compressed air stream 114 guides air under pressure through the suction unit 110 between the air inlet 112 and the air outlet 113, wherein the compressed air stream 114 communicates laterally with the suction opening 111. The suction opening 111 forms a throttle section 301 and hence comprises a smaller opening diameter (i.e. at the downstream end of the suction opening 111 inside the suction device 110) close to the compressed air stream 114 than the larger opening diameter (i.e. at the upstream end of the suction opening 111) close to the suction hole 104 of the hold-down element 102. Hence, a Venturi effect creates a vacuum inside the suction opening 111 such that air is sucked from the suction through hole 104 of the hold-down element 102 into the suction unit 110.

(25) Hence, it is possible to connect a pressurized air source 220 to the suction unit 110 in order to draw air through the suction opening 111 and further to blow the air through the air outlet 113 out of the suction unit 110.

(26) FIG. 4 shows a top view and FIG. 5 a side view of the supporting frame 115, the guiding structure 101 and the hold-down element 102 according to an exemplary embodiment of the present invention. The guiding structure 101 and the hold-down element 102 are mounted to mounting bars 501 of the supporting frame 115. The hold-down element 102 is movable with respect to the guiding structure 101 between an active position for holding the flat element 202 down and an inactive position in which the flat element 202 is movable for passing the support section 103 of the hold-down element 102. The active position as shown in FIG. 4 and FIG. 5 of the hold-down element 102 is defined by a position wherein the flat element 202 is arranged on the support section 103 of the hold-down element 102 and hence the flat element 202 is sucked to the supporting section 103 by sucking air through the suction holes 104. In an inactive position of the hold-down element 102 with respect to the guiding structure 101, the flat element 202 is not supported on the support section 103, such that the air drawn through the suction holes 104 does not hold the flat element 202 to the support section 106.

(27) Specifically, the hold-down element 102 and more specifically the support section 103 of the hold-down element 102 is movable in the direction to the support area 106 of the guiding structure 101 and also away from the support area 106 of the guiding structure 101. As shown in FIG. 4 and FIG. 5, the hold-down element 102 is formed such that the hold-down element 102 is rotatable (indicated by the arrow 302 in FIG. 4 and FIG. 5) between an active position and an inactive position. Hence, by rotating the hold-down element 102 from the active position to the inactive position, the outlet of the suction holes 104 and in other words the support section 103 of the hold-down element 102 is rotated into the active position or away from the active position into the inactive position.

(28) For example, in the active position, the support section 103 may be arranged in the same plane as the supporting area 106 of the guiding structure 101 (see FIG. 4 and FIG. 5). In the inactive position, the support section 103 is moved and in particular rotated out of the plane, in which the support area 106 of the guiding structure 101 is arranged.

(29) The hold-down element 102 is in particular formed by a hollow rectangular beam, wherein one surface of the rectangular beam forms the support section 103 including the suction holes 104. Furthermore, in an exemplary embodiment, a further surface of the rectangular beam may form a further support section comprising further suction holes coupled also to the suction opening of the suction device. For example, the quantity of the further suction holes and/or the diameter of the further suction holes of the further support section may differ from the quantity of the suction holes 104 and/or of the diameter of the suction holes of the support section 103. Hence, a different suction capacity between the support section 103 and the further support section is provided.

(30) The support section 103 comprises an edge 401 extending along the extending direction 116 and perpendicular to the transport direction T, wherein the support section comprises a total width w defined along the transport direction T. Each of the suction holes 104 is arranged spaced apart from the edge 401 with a distance of , or 1/10 of the total width w of the support section 103. Hence, if the suction holes 104 are arranged close to the edge 401 which is the downstream edge with respect to the transport direction T, an upstream end of the flat element 202 may be held to the support section 103 of the hold-down element 102, wherein the downstream end of the same flat element 202 may be already located within the subsequent paper processing device 210, for example.

(31) FIG. 6 and FIG. 7 show a system 200 for processing flat elements, wherein a gripper bar device 601 of the system 200 moves the flat elements 202, 202 to a stack 602 of flat elements 202, 202 according to an exemplary embodiment of the present invention.

(32) The gripper bar device 601 is movable along the transport direction T. The gripper bar device 601 is adapted for gripping (mechanically or by underpressure) a flat element 202, 202 selectively, such that the flat element 202, 202 can be moved with the gripper bar device 601 along the transport direction T.

(33) The hold-down element 102 is arranged in position I closer to a stopper element 603 than in position II. The location of the hold-down element 102 in position I is used for flat elements 202 with a smaller width and the position II of the hold-down element 102 is used for flat elements 202 with a larger width.

(34) In the exemplary embodiment shown in FIG. 6 and FIG. 7, the hold-down element 102, 102 is movable along the transport direction T along the supporting frame 150 so that the hold-down element 102, 102 is adjustable with respect to a size of the flat elements 202, 202.

(35) In the exemplary embodiment shown in FIG. 6 and FIG. 7, the flat elements 202, 202 are fixed at a desired position by the hold-down elements 102, 102. Next, as shown in FIG. 7, the gripper bar device 601 grips the respective flat element 202 and moves the respective flat element 202 to a stopper element 603. Next, the gripper bar device 601 releases the respective flat element 202 and the flat element 202 is laid on a stack 602 of flat elements 202.

(36) It should be noted that the term comprising does not exclude other elements or steps and a or an does not exclude a plurality. Also elements described in association with different embodiments may be combined. It should also be noted that reference signs in the claims should not be construed as limiting the scope of the claims.

(37) In certain embodiments two or more suction units may be provided, as is illustrated by way of example by the presence of suction units 110 in FIG. 8; here referenced V1, V2 and V3.

(38) In certain of these arrangements the different suction units provide the suction effect in different zones of the hold down element. For example, one suction element could provide the suction effect in a part of the hold down element corresponding to the area occupied by a sheet having a first (smaller) dimension in the direction of the hold down device, as it passes over the hold down element in use. This zone could be in a central part of the hold down element, for example. A second suction element could provide the suction effect in the remaining parts of the hold down element, corresponding to the area occupied by a sheet having a second (larger) dimension in the direction of the hold down device, as it passes over the hold down element in use.

(39) This arrangement allows the suction elements that are needed to hold down a particular sheet size or width (for a particular job) to be activated and those which are not needed to be deactivated. This brings benefits of reduced energy consumption and reduced noise. For increased energy efficiency, internal baffles may be introduced in the hold down device segregating one zone of the hold down element from the other. This may have the effect of preventing or restricting air flow between a suction hole associated with a first zone and a suction unit associated with a second zone. While any suitable form of baffle may be used, in one simple embodiment one or more simple bungs or other blockage made from any suitable material may be inserted into the hold down element moved to one or more predetermined positions. An interference fit between the bungs and the interior surface of the hold down element may be used to ensure that the bungs do not move from their intended position.

(40) It will be understood that where more than two widths of sheet are used, for example three or four widths, further hold down zones may be employed with further corresponding suction units.

(41) In other arrangements two or more suction units could be connected to the same zone of the hold down element. In this manner, the suction effect acting in a given zone could be increased for a given a level of suction associated with a given suction unit. One or more suction units could be connected to one side of the hold down device 102, as is illustrated by suction units V1 and V2 in FIG. 8. Alternatively, the one or more suction units could be connected to the other side of the hold down device 102, as is illustrated by suction unit V3 in FIG. 8. As a further alternative, one or more suction units could be connected to a first side of the hold down device 102 and the same or indeed a further one or more suction units may be connected to the second side of the hold down device 102. In this manner the suction force at different points along the length of the hold down device 102 may be brought to the desired level and thus embodiments of the present invention would be suitable for a working with greater range of sheet substrates (for example, heavier substrates or substrates with different surface finishes) and sheet handling speeds.

(42) It will also be understood that in yet other arrangements of the invention the hold down element may be divided into zones with each zone being provided with suction by at least one suction unit but with certain zones being provided with suction from two or more suction units. In this manner the certain zones may be subject to significantly different levels of suction forces to others.

LIST OF REFERENCE SIGNS

(43) TABLE-US-00001 100 arrangement 101 guiding structure 102 hold-down element 103 support section 104 suction hole 105 suction air stream 106 support area 107 transport rollers 108 connection tube 110 suction unit 111 suction opening 112 air inlet 113 air outlet 114 compressed air stream 115 supporting frame 116 extending direction 120 compressed air connection element 200 system 201 conveyor element 202 (paper) flat elements/sheets 203 roller element 204 connection tube 210 paper processing device 220 external pressurized air source 221 connection locations 230 building 301 throttle section 401 edge 501 support bar 601 gripper bar 602 stack of flat elements I position of hold-down element II further position of hold-down element T Transport direction w total width