GB2341597A

GB2341597A - Separating sheets

Info

Publication number: GB2341597A
Application number: GB9921981A
Authority: GB
Inventors: Thomas Walther
Original assignee: MAN Roland Druckmaschinen AG
Current assignee: Manroland AG
Priority date: 1998-09-16
Filing date: 1999-09-16
Publication date: 2000-03-22
Anticipated expiration: 2019-09-16
Also published as: GB9921981D0; DE19842344C2; DE19842344A1; GB2341597B; FR2783244A1

Abstract

In a sheet treating machine, the sheets are separated by at least one cutter running in the transport direction into a plurality of adjacently lying partial sheets (2a, 2b) and the partial sheets (2a, 2b) are moved away from one another transversely to the transport direction so that a space is formed between them and deposited in a delivery (1) falling freely on to adjacently lying piles (3a, 3b). The movement apart of the partial sheets (2a, 2b) takes place in the delivery (1) with the aid of a separating unit (6), which is arranged in the centre between piles (3a) and (3b) and which moves apart each of the arriving partial sheets (2a, 2b) form one another and diverts them to pile 3a or 3b respectively. Device (6) comprises a rail extending in the direction of the separating line of sheets 2a and 2b, whose upper-facing end is "roof-shaped".

Description

2341597 PROCESS FOR TRANSPORTING SHEETS AND SHEET TREATING MACHINE WORKING

IN ACCORDANCE WITH THE PROCESS The invention relates to a process for transporting sheets in a sheet treatment machine, particularly a printing press, in which the sheets are divided by at least one cut running in the transport direction into a plurality of'adjacently lying partial sheets, wherein the partial sheets are moved apart from one another transverse to the transport direction, so that between them a distance is formed, and the partial sheets are deposited in a delivery freely falling on to adjacently lying piles. The invention further relates to a sheet treating machine suited for carrying out this process.

From DE 196 53 403 Al, a sheet treating machine with a treatment cylinder and a longitudinal cutting device fitted cooperating with this is known by which the sheets are divided into a plurality of adjacently lying partial sheets. For transportation of the sheets, the treatment cylinder has two gripper systems lying adjacent one another in the axial direction. The one gripper system is movable in the axial direction relative to the other and, as soon as both partial sheets have been wholly separated by a longitudinal cut, executes a stroke by means of a cam roll cooperating with a cam disc in the axial direction by which both of the partial sheets are moved from one another. The partial sheets moved from one another are then transferred to a chain gripper system of a chain conveyor and deposited in a delivery on adjacently lying piles.

The object underlying the invention is to provide a process of the initially noted type which is simple and which can be carried out with little machinery outlay and which does not restrict the useful width of the sheet treatment machine.

In accordance with the invention, this problem is solved by moving the partial sheets apart from one another on deposition in the delivery during their falling down. The movement apart from one another of the partial sheets can be effected-by sliding along against a separating device and/or by an airstream.

Thus, in accordance with a first feature of the present invention, there is provided a process for transporting sheets in a sheet treating machine in which the sheets are separated by means of at least one cut running in the transport direction into a plurality of adjacently lying partial sheets, and the partial sheets are moved apart from one another transverse to the transport direction so that between them a space is formed and subsequently deposited in a delivery freely falling on to adjacently lying piles, wherein the partial sheets are moved apart from one another in the delivery during the falling down for deposition.

The process in accordance with the invention has the advantage that the sheet transport of the partial sheets cut one from another in the sheet treatment machine is not different from the sheet transport of a single sheet of double width. Only within the delivery and after the sheet feeding units, for example a chain gripper system, has freed the partial sheets, are these moved apart from one another and deposited on to separate adjacently lying 5 piles. The space requirements necessary for the interspace between the piles is, as a general rule, present in sheet deliveries so that for carrying out the process in accordance with the invention seen from the point of view of the building in of a separating unit for moving apart the sheets, no constructional changes are necessary at the delivery. The process in accordance with the invention accordingly is especially suited for application in printing presses in order, for example, to print sheets in large format and, in this connection, with the aid of a cutting unit separate them into two medium format sheets, wherein the medium format sheets are piled and can be further worked on separately.

The invention, in a second aspect, provides a sheet treating machine, for example a printing press, with a cutting unit in which the sheets are divided by means of at least one cut running in the transport direction into a plurality of adjacently lying partial sheets, and a delivery in which the partial sheets are deposited freely falling on to adjacently lying piles, the machine including, between the piles, a separating unit by means of which the falling partial sheets are moved away from one another.

The separating device can be connected easily demountable with the delivery in order that a changeover to full sheet or partial sheet deposition is possible in a short time. Furthermore, at the delivery, an electric sensor can be provided which senses whether the separating device is built in or not, and generates an electrical signal characterising the respective constructional condition. The electrical signal can be transmitted to the press control in order to enable this to carry out control processes necessary for working with partial sheets. If the delivery has sheet straightening pushers automatically pre-adjustable in their spacing, then with the aid of the electrical signal, a moving apart of the sheet straightening pushers by an amount corresponding to the width of the separating device is effected.

For the further processing of the partial sheets, it can be desirable that the fibre direction of the printed material runs parallel to the cylinder axis. In order to maintain this, the full sheet must be printed broad width in double format, i.e. the fibre direction of th6 printed material runs in the peripheral direction of the cylinder. However, this places higher requirements on sheet guidance. In accordance with the invention for this case the sheet treating machine has on the cylinders additional swivellable away sheet guiding rollers, which are arranged on the cutting line since there, as a rule, the sheets do not contain any subject.

The invention is subsequently illustrated and explained in more detail with reference to various exemplary embodiments, which are illustrated diagrammatically in the accompanying drawings in which:

Figure 1 shows a schematic illustration of a delivery of a sheet treatment machine equipped with a separating unit.

Figure 2 shows a separating unit with swivellable plates, Figure 3 shows a separating unit with horizontally movable plates, Figure 4 shows a separating unit with roller bodies, Figure 5 shows a separating unit with upwardly directed airstreams, Figure 6 shows a separating unit with downwardly directed 5 airstreams, Figure 7 shows a separating unit with air cushions.

Figure 1 shows the rearside of a delivery 1 of a sheet printing press, in which large format sheets after printing are each separated by means of a cutting unit by a cut running in the transport direction in the centre of the sheet into adjacently lying partial sheets 2a, 2b. The adjacently lying partial sheets 2a, 2b are in the same way as unseparated sheets fed by means of a feed unit into the delivery 1 and there deposited separated on to two adjacently lying piles 3a, 3b. Both of the piles are located on separate pallets 4 which are set down on a lifting platform of the delivery 1. By the use of separate pallets, the possibility is present of feeding piles 3a, 3b individually to further processing. The separated deposition of the partial sheets 2a, 2b on the piles 3a, 3b is made possible by a separating unit 6 which is arranged in the centre between the piles 3a, 3b and which moves apart each of the arriving partial sheets 2a, 2b from one another and diverts them to both of the piles 3a, 3b. The separating device 6 consists of a rail arranged edgewise extending in the direction of the separating line of the arriving partial sheets 2a, 2b which is fixed in the delivery 1. The upper edge of the rail is located above the deposition plane of the piles 3a, 3b. It has in the fashion of a double pitch roof two surfaces 7 inclined symmetrically to the vertical central plane of the rail, which intersect with their upper longitudinal sides and thereby form a sharp edge 8. Downwardly at the inclined surfaces 7, these connect with side faces 9-parallel to the vertical central plane. To both sides of the separating unit 6 at a distance corresponding to the width of the partial sheets 2a, 2b there are provided customarily fitted out sheet aligning pushers 10. 5 In operation, the adjacently lying partial sheets 2a, 2b are fed by the not illustrated transport unit over the separating unit 6 and then let go. By their weight and by blown air acting from above on the partial sheets 2a, 2b the sheets fall downwardly, wherein they impact with their cut edges turned towards one another on the inclined surfaces 7 of the separating units 6. Hereby the partial sheets 2a, 2b are moved apart from one another and diverted to the respective piles 3a, 3b. The straightening pushers 10 prevent, in this connection, that the partial sheets 2a, 2b are diverted too far outwardly and take care in combination with the side surfaces 9 of the separating unit 6 for exact lateral alignment in that they carry out in known fashion an oscillating movement transverse to the piles 3a, 3b.

The rail of the separating unit 6 can stand still, but can also carry out horizontal oscillating movements transverse to its longitudinal direction in order to facilitate the sliding along of the sheets against the inclined surfaces. The oscillations can be transferred at the axial ends on to the rails, e. g. by means of an electric motor provided with an imbalance which is connected with the rail.

For moving apart the partial sheets 2a, 2b and for forming straight piles 3a, 3b, it suffices if the separating unit 6 as illustrated in Figure 1 is located between the upper parts of the piles 3a, 3b. Provided below the separating unit 6 for securing the piles 3a, 3b against slippage, there is provided a separating element 11 variable in its length e.g. a cable which can be 7 rolled up, a telescopic rod, or a telescopic wall. The separating element 11 is fixed to the separating unit 6 and to the lifting stage 5, and can be constructed together with the separating unit 6. The braking, catching and alignment of the partial sheets 2a, 2b in the transport direction takes place by means customarily provided for this, which, for reasons of simplicity, are not illustrated in the drawing. In the configuration of the separating unit 6, the necessary space requirements for these means can be taken into account.

The subsequently described exemplary embodiments show variations of the separating unit 6, which yet further improve the separation movement and deposition of the partial sheets and which can be used individually or partially also in combination with one another.

In the separating unit shown in Figure 2, the inclined surfaces 7 are formed by separate plates 12 which in each case with their lower longitudinal side are swivellably mounted on a carrier 13 arranged between the plates 12. By means of.a drive arranged in the carrier 13, the plates 12 can be swivelled to and fro in the fashion of a sheet straightening pusher in the rhythm of the arriving partial sheets, in order accordingly to accelerate the transverse movement Of the partial sheets and thereby the achievement of the end position.

Figure 3 shows a variation of the separating unit 6 in which the inclined surfaces 7 and the upper part of the side surfaces 9 are formed of horizontally movable plates 14 which are mounted in guides on the carrier 13. By means of a drive, the plates 14 can be set into an oscillating horizontal movement. Also hereby the movement of the partial sheets apart from one another and the pile formation are improved..

The separating unit 6 according to Figure 4 has in the region of the surfaces 7 a plurality of roller bodies 15 rotatable about a longitudinal axis, which can be driven in such a fashion that their outerlying cover surfaces in each case move downwardly. The edges of the partial sheets coming into contact with the roller bodies 15 receive hereby a movement impulse directed downwardly and outwardly.

Figure 5 shows a separating unit 6 in the form of a longitudinally extending rail which has along the upper edge 8 a number of air outlet openings connected to a blown air source. By the air outlet. openings upwardly directed air streams 16 are generated which drive the arriving partial sheets from one another. The airstreams 16 can be generated in intermediate fashion in the rhythm of the arriving sheets in order to avoid air turbulence. This pneumatic arrangement for separating the particle sheets can be combined with the previously described mechanical arrangements.

In the separating unit 6 shown in Figure 6 in the surfaces 7, air outlet openings 17 are provided from which on the feed of blown air downwards along the surfaces 7, flowing airstreams 18 emerge. By the airstreams 18, the edges of the arriving partial sheets are captured and fed downwardly, whereby the deposition is accelerated. This arrangement can also be combined with that shown in Figure 5.

Figure 7 shows an arrangement of the separating unit 6 in which the inclined surfaces 7 have a plurality of small air outlet openings, from which blown air emerges diffusely with small speed. Hereby across the surfaces 7, air cushions 19 are built up which take care of a practically contact- free sliding along of the partial sheets against the surfaces 7.

Claims

1. A process for transporting sheets in a sheet treating machine in which the sheets are separated by means of at least one cut running in the transport direction into a plurality of adjacently lying partial sheets, and the partial sheets are moved apart from one another transverse to the transport direction so that between them a space is formed and subsequently deposited in a delivery freely falling on to adjacently lying piles, wherein the partial sheets are moved apart from one another in the delivery during the falling down for deposition.

2. A process according to Claim 1 wherein the partial sheets are moved away from one another by sliding along against a separating unit.

3. A process according to Claim 1 or 2 wherein the partial sheets are moved apart from one another by means of an airstream.

4. A process for transporting sheets in a sheet treating machine with a delivery substantially as hereinbefore described with reference to the accompanying drawings.

5. A sheet treating machine with a cutting unit in which the sheets are divided by means of at least one cut running in the transport direction into a plurality of adjacently lying partial sheets, and a delivery in which the partial sheets are deposited freely falling on to adjacently lying piles, the machine including, between the piles, a separating unit by means of which the falling partial sheets are moved away from one another.

6. A sheet treating machine according to Claim 5 wherein the separating unit has two surfaces symmetrically inclined relative to a vertical central plane, the distance of which from one another increases from above to below. 5

7. A sheet treating machine according to Claim 6 wherein the inclined surfaces are formed on the upper edge of a rail arranged edgewise between the piles with parallel side surfaces.

8. A sheet treating machine according to Claim 7 wherein the rail is movable by means of a drive transversely to the vertical central plane in oscillating fashion.

9. A sheet treating machine according to Claim 6 or 7 wherein each surface is formed by a separate plate.

10. A sheet treating machine according to Claim 9 wherein the inclination of the separate plates is variable.

11. A sheet treating machine according to Claim 9 or 10 wherein the separate plates are movable in oscillating fashion by means of a drive transversely to the vertical central plane.

12. A sheet treating machine according to any one of Claims 4 to 6 wherein the separating device has rotatingly driven roller bodies, the rotational axes of which run in the longitudinal direction of the separating device.

13. A sheet treating machine according to any one of Claims 4 to 11 wherein the separating unit has air outlet openings connected to a source of blown air which generate an airstream directed upwardly on to the - 11 separation line of the arriving partial sheets.

14. A sheet treating machine according to any one of Claims 5 to 13 wherein at the upper edge of the surfaces, air outlet openings connected to a source of blown air are provided which generate a downwardly directed airstream.

15. A sheet treating machine according to any one of Claims 5 to 13 wherein in the surfaces, air outlet openings connected to a source of blown air are arranged for generating an air cushion.

16. A sheet treating machine according to any one of Claims 5 to 15 wherein the separating unit is connected with the delivery in easily dismountable fashion.

17. A sheet treating machine according to Claim 16 wherein below the separating unit in the interspace between the piles, a separating element variable in its length is arranged which is connected with the separating unit and the lifting platform.

18. A sheet treating machine according to any one of Claims 5 to 17 wherein an electrical sensor is fitted to the delivery which generates an electrical signal which indicates whether the separating unit is installed in the delivery or not.

19. A sheet treating machine substantially as hereinbefore described with reference to the accompanying drawings.

20. A sheet treating machine in accordance with any one of Claims 5 to 10 and constructed as a printing press.