EP1041028B9 - Delivery device of a sheet printing machine - Google Patents

Abstract

The delivery table (1) has circulating pick-up pieces (9.1) which transfer the processed sheets (3) in the conveyor's direct to a brake (11). The side edges of the sheets have guides (24,24',24) which guide the sheets to the brake during transfer. The guides support the side edges of the sheets by means of guide surfaces against which press the sheets' side edges.

Description

The invention relates to a boom of a sheet processing Printing machine with operationally rotating grippers, which the pass the processed sheet in a conveying direction to a sheet brake.

The publication DE 44 35 988 A1 discloses with variable speed revolving suction devices, which by means of the revolving gripper transported sheets in a neighboring one of the trailing edge Capture the area of the sheets at a time when the Speed of the suction devices with the processing speed the press matches. Then the grippers give the respective sheets detected by the suction devices free and the Suction devices are at a reduced orbital speed slowed down, with which they in turn finally formed the bow Release the stack.

This process only runs smoothly if this is ensured in particular is that the one to be grasped by the suction devices is the following Edge of the arc adjacent area of each arc in particular at the time when the suction devices each Area should be largely flutter-free.

Flutter-free guidance of printed sheets in a delivery is also possible In order to avoid smearing on the sheets applied print image an important prerequisite for achieving flawless print products. Efforts are state of the art to create this requirement, in particular the publication

DE 42 39 561 A1 removable. In this it is proposed to be whip-like Avoid movements of the trailing edge of the sheet in that a parallel to the path along which the grippers under a respective arch Forced guidance of the leading edge of the respective in the conveying direction Transport arc, arranged guide surface is provided, which in the Direction of conveyance of the grippers continuously at sheet conveying speed is movable, the guide surface being formed by means of a suction belt arrangement which is one of the trailing edges of each sheet holds the adjacent area of the same under suction of this area, so that each sheet is not only in the area of its leading edge but is also positively guided in the area of its trailing edge.

US-A-4,225,129 discloses a boom according to the Preamble of claim 1

The invention has for its object the boom mentioned above to design such that a safe takeover of the bow on the part of Arch brake is guaranteed.

This object is solved by the features of claim 1.

With this, even at relatively high processing speeds largely smooth running of the arches achieved in one section of the path which these should be captured by the sheet brake. In particular, can with the device designed in this way selectively one of the trailing ones Edge of a respective arc adjacent area thereof by means of the Bow brake can be detected safely. The device is thus special suitable for braking sheets printed on both sides and makes one unnecessary such a setting of the sheet brake that this sheet printed on both sides detected in unprinted corridors running in the conveying direction.

Before the sheet brake is reached, prints are printed on both sides in particular Arch to avoid smearing usually over an between this and an arch guide surface formed air cushion, the Gripper a gripper track following the course of the sheet guide surface passed through. This air cushion is created by a diverse arrangement of Blow or suction nozzles in the sheet guiding surface are preferably designed such that the sheets run smoothly over the sheet guide surface. The said Air cushions also form one, particularly in the area of the sheet brake Flow out, which in conventional cantilevers creates the respective Sheet on braking elements of the sheet brake, such as suction rolls, Suction wheels or endless belts or a suction box Complicate cords. With the construction of a boom according to the invention this disadvantage is also eliminated.

An advantageous embodiment provides that the sheet guides the lateral edges of the sheet include supporting guide surfaces which the side edges of the sheets can be pressed on.

According to a first variant of this, the side edges are the arches preferably under the effect of a pressure difference existing on the elbows can be pressed against the guide surfaces, while according to a second variant the side edges of the sheets to the Guide surfaces can be pressed. In both variants are the Guide surfaces according to a first embodiment are preferably silent while according to a second embodiment, preferably by means of operation Direction of conveyance of running strands of circumferential belts are formed.

It is also preferred for all variants and configurations provided that the sheet guides at the mutual distance of the side edges of the sheet are customizable.

The invention is described in more detail below with reference to drawings explains which in its entirety the essential features of the invention reproduce them using different configurations.

Fig. 1

von einer Bogen verarbeitenden Druckmaschine in schematischer Darstellung einen Abschnitt, der einen Ausleger mit einer Bogenbremse umfaßt,

Fig. 2

in schematischer Darstellung eine Draufsicht auf einen die Bogenbremse umfassenden Bereich gemäß einem Ausführungsbeispiel,

Fig. 3

eine Ausgestaltung in einer Ansicht in Richtung des Pfeiles III in Fig. 1,

Fig. 4a

einen Schnitt entlang einer der Linie IV in Fig. 2 entsprechenden Linie für den Fall einer Ausbildung von betriebsmäßig stillstehenden Führungsflächen,

Fig. 4b

einen Schnitt entlang einer der Linie IV in Fig. 2 entsprechenden Linie für den Fall einer Ausbildung von Führungsflächen an umlaufenden Bändern oder dergleichen.

In the drawings:

Fig. 1

a section of a sheet-processing printing press, which comprises a delivery arm with a sheet brake,

Fig. 2

a schematic representation of a plan view of an area comprising the sheet brake according to an embodiment,

Fig. 3

an embodiment in a view in the direction of arrow III in Fig. 1,

Fig. 4a

3 shows a section along a line corresponding to line IV in FIG. 2 in the event that operationally stationary guide surfaces are formed,

Fig. 4b

a section along a line corresponding to line IV in Fig. 2 in the case of formation of guide surfaces on circumferential belts or the like.

As can be seen from FIG. 1, a boom 1 follows a last one Processing station of a printing press. Such a processing station can be a printing unit or an aftertreatment unit, for example a coating unit. In the present example, the last one is Processing station around a printing unit 2 working in the offset process a pressure cylinder 2.1. This leads a respective sheet 3 in one means the direction of rotation arrow 5 indicated processing direction by a Printing gap between the printing cylinder 2.1 and a so cooperating blanket cylinder 2.2 and then passes it to a chain conveyor 4 by opening the pressure cylinder 2.1 arranged to grasp the sheet 3 on a gripper edge on leading end of the bow provided grippers. The chain conveyor 4 comprises two conveyor chains 6, each of which is along a respective one Sidewall of the chain boom 1 rotates during operation. A respective one Conveyor chain 6 loops around one of two synchronously driven Drive chain wheels 7, whose axes of rotation are aligned with one another and is in the The present example has one each relative to the drive sprockets 7 downstream with respect to the processing direction Deflection sprocket 8 out. Extend between the two conveyor chains 6 gripper systems 9 carried by them with grippers 9.1, which gaps drive through between the grippers arranged on the pressure cylinder 2.1 and a respective sheet 3 while gripping said gripper edge at the leading end of the sheet 3 immediately before opening the am Pressure cylinder 2.1 arranged gripper take it over a Transport the sheet guiding device 10 to a sheet brake 11 and open there for the transfer of the sheet 3 to the sheet brake 11. This conveys the bow to the processing speed reduced storage speed and gives it after reaching it in turn free, so that a respective now slowed sheet 3 finally impinges on leading edge stops 12 and aligns with them and at these opposite trailing edge stops 13 together with preceding and / or following sheet 3 forms a stack 14, which can be lowered to the extent that the stack 14 by means of a lifting mechanism increases. Of the hoist, only one is the stack 14 in FIG. 1 load-bearing platform 15 and this load-bearing, dash-dotted lines Lift chains 16 reproduced.

The conveyor chains 6 are along their paths between the Drive sprockets 7 on the one hand and the deflection chain wheels 8 on the other guided by chain guide rails, which thus the chain tracks of Determine chain dreams. In the present example, the sheets 3 of the lower chain center in Fig. 1 transported. The one that this one went through Section of the chain track follows a, facing this, at the Sheet guiding device 10 formed sheet guiding surface 17. Between this and the respective arc 3 passed over is preferably operationally on Air cushion formed. For this purpose, the sheet guiding device 10 is included in the Sheet guiding surface equipped 17 blowing air nozzles, of which in Fig. 1 is only a representative of their entirety, and in symbolic Representation in the form of the nozzle 18 is reproduced.

To prevent the printed sheets 3 from sticking together in the stack 14 prevent are on the way of the bow 3 from the drive sprockets 7 to Sheet brake 11, dryer 19 and dusting device 20 intended.

To avoid excessive heating of the sheet guide surface 17 by the dryer 19 is a coolant circuit in the sheet guide device 10 integrated, symbolically in Fig. 1 by an inlet port 21 and one Outlet port 22 on one of the sheet guide surface 17 associated Coolant pan 23 is indicated.

The chain guide rails are shown in FIG. 1 waived. However, the course of the same in the present example is from that the chain dreams recognizable.

The schematic plan view shown in Fig. 2 on a Area of the boom comprising the bow brake 11 is a preferred one mutual assignment of the sheet brake 11 on the one hand and on the other hand removable from sheet guides 24. In the example shown are Bow guides 24 formed by means of guide surfaces 24.1 and clocked Hold-down 24.2, which are designed here in the form of rollers. The Hold-down devices 24.2 press the lateral ones in a working position Edges of a respective sheet 2 on the guide surfaces 24.1 and temporarily into a distance from the guide surfaces 24.1 Dodge position spent when a leading edge of a particular Arc 3 passes the place where the hold-down 24.2 is in its Working position, d. H. the hold-down devices 24.2 are clocked and give way the gripper systems 9. A mechanism suitable for this is shown in FIG. 3 evident, which will be discussed in more detail.

The sheet brake 11 in the embodiment shown in FIG. 1 three synchronously rotating endless brake bands 11.1, 11.2 and 11.3 which each have at least one cam 11.1 ', 11.2' and 11.3 ', via at least one of the respective brake bands 11.1, 11.2; 11.3 penetrating hole in time with the successive bows with a vacuum generator, not shown here, is connected.

The bow 3 move in the direction indicated by the arrow 25 Conveying direction towards the sheet brake 11 and the brake bands 11.1, 11.2 and, 11.3 are synchronized with such a variable by means of a motor 27 Speed driven that the cams 11.1 ', 11.2 ', 11.3' of the underside of one of the sheets 3 in the area thereof face the trailing pressure-free edge and the same Have speed like the revolving grippers 9.1. In this Operating state take over the cams 11.1 ', 11.2', 11.3 ', the bow 3 and the grippers 9.1 release it. Especially in this operating state the respective sheet 3 on its side edges by means of Sheet guides 24 out. This is the case in the configuration according to FIG. 2 realized in that the hold-down 24.2 the sheet 3 to the Press on guide surfaces 24.1. The hold-down devices 24.2 are of this type placed that a respective sheet has left the hold-down 24.2 again if the cams 11.1 ', 11.2', 11.3 'after the respective one has been taken over Sheet 3 can be delayed to a depositing speed.

2 is a respective one in the rest Guide surface 24.1 by means of one each operationally at the speed of rotating gripper 9.1 in the direction of arrow 25 corresponding to the conveying direction running dreams each formed a circulating band 24.3, while at a respective embodiment not shown in the drawing Guide surface by means of an outer surface of each Hold-down 24.2 opposite, possibly freely rotatable roller is formed.

The rollers 24.4 wrapped in a respective band 24.3 and one driving motor 26 are in a manner not shown by a respective sled carried transversely to the arrow 25 specified conveying direction is displaceable, so that the sheet guides 24 the mutual distance of the side edges of the sheet 3 are adjustable. This is indicated in Fig. 2 by a with solid lines reproduced position of the sheet guides 24 when processing sheets 3 with maximum format and one with broken lines Position of the sheet guides 24 when processing sheet 3 with minimal Format.

In a preferred embodiment, the hold-down devices 24.2 comprise free rotatable rollers, by means of which the lateral edges of the sheet 3 to this supporting guide surfaces 24.1 are pressed.

3 shows the above-mentioned operating state, in which a Sheet 3 on the trailing pressure-free edge of the same on the part of Cam 11.1 ', 11.2' and 11.3 'is taken over. This operating state is reached after the grabs 9.1 initially avoided Downholders 4.2 have returned to their working position in soft the lateral edges of the sheet 3 to the guide surfaces 24.1 press down. The latter are preferably at a somewhat lower level than that Top sides of the cams 11.1 'in the said operating state, 11.2 '. With this measure, a safe transfer of the sheet 3 to the Cam 11.1 ', 11.2', 11.3 'further favored. 3 is also a Embodiment shown for a mechanism already mentioned, with With the help of the hold-down devices 24.2, the grippers 9.1 not shown in FIG. 3 dodge and then return to their working position, in which the hold-down 24.2 the respective sheet 3 to the Press on guide surfaces 24.1.

A hold-down 24.2, which is preferably designed as a roller, is on one End of a respective one comprising a curve follower 28 and in present example two-armed lever 29 to one in the working position the hold-down device horizontal and transverse to the conveying direction - see arrow 25 in Fig. 2 - oriented axis 3 rotatably added. The lever 29 is in one plane perpendicular to the direction of conveyance (arrow 25 according to FIG. 2) pivotable and by means of a spring 30 under a certain bias held the working position. The curve follower 28 is also preferred as Freely rotatably mounted roller and on a rotating cam 31 employed, which the pivot holder 24.2 always temporarily from his working position in his Dodge position shifts when the grabs pass the location where the Hold down 24.2 take up their working position.

The configuration shown in Fig. 4a looks fixed Guide surfaces 24.1 ', which here according to the present Sectional view perpendicular to the plane of the figure. For this Guide surfaces 24.1 'apply in the same way as for guide surfaces 24.1 2 that they are downstream with respect to the conveying direction Extend area in which upstream sections of the brake bands 11.1, 11.2, 11.3 located between the guide surfaces 24.1 ' are arranged so that the sheet guides 24. ' or 24 hers also fulfill the intended function safely, namely a respective one Sheet 3 during its transfer to the sheet brake 11 to the the conveying direction lateral edges of the sheet 3.

In the case of an embodiment with 24.7 formed on fixed suction strips Guide surfaces 24.1 'according to FIG. 4a can also do this function Hold downs, for example with those of the type described above and Way of working, to be fulfilled; in the example shown in FIG. 4a, however, that is Press the respective sheet 3 against the guide surfaces 24.1 'by means of a effective pressure difference realized on the respective sheet 3. This is done in a respective guide surface 24.1 'on the respective lateral edge of the sheet 3 opposite channel 24.5 incorporated, which is in the conveying direction in extends essentially along the guide surface 24.1 'and in which preferably at its downstream with respect to the conveying direction End of a suction opening 24.6 which can be connected to a vacuum generator 32 empties. The thus on a by means of a gripper system 9 on the Guide surface 24.1 'drawn sheet 3 generated pressure difference between The top and bottom of the sheet 3 presses the latter against the Guide surface 24.1 '.

To ensure that the side edges of the Sheet 3 to the one assigned to each of these edges The guide surface 24.1 'projects beyond the guide surface 24.1' upstream sheet guiding surface 17 by a certain amount h. Just as the guide surfaces 24, as can be seen in FIG. 4a, the Guide surface 24. 1 'on the other hand, however, still below that level, which the cams 11.1 ', 11.2', 11.3 'of the brake bands 11.1, 11.2, 11.3 take if they are with the rotating brake bands 11.1, 11.2, 11.3 move in the conveying direction.

The configuration shown in FIG. 4b provides an arch guide 24 ", at which in turn guide surfaces 24.1 "by means of operational Direction of conveyance of running dreams of endless circulating belts 24.3 'is formed are. The dreams running in the direction of conveyance are brushed analogously to the Suction strips 24.7 according to FIG. 4a and they are suction strips 24.7 ' provided with holes 24.8, which with a channel 24.5 according to FIG. 4a corresponding channel 24.5 'communicate to the Vacuum generator 32 can be connected, so that on the underside of a lateral edge of one of the grippers 9.1 one of the gripper systems 9 the run drawn in the conveying direction 3 arc a negative pressure is buildable, which is thus a between the top and bottom of the sheet 3 Pressure difference generated that the sheet 3 to the guide surface 24.1 '' presses. The pressure difference mentioned on the respective sheet 3 is thereby preferably maintained at least until this sheet 3 on its trailing pressure-free edge on the part of the cams 11.1 ', 11.2', 11.3 'detected is. However, this pressure difference can also be maintained until the arc 3 detected by the cams 11.1 ', 11.2', 11.3 'on the part corresponding griffin 9.1 is released to then by means of Bow brake 11 to be decelerated to a depositing speed. A thus in the rhythm of the successive beats clocked effect of Pressure difference on the respective sheet 3 is preferably realized by that the channel 24.5 'continuously with the Vacuum generator 32 communicates and downstream up to one Point extends at which the braking effect of the sheet brake 11 is effective becomes. The same also applies to channel 24.5 4a, channels 24.5 and 24.5 'being preferred have such cross-sections that they are for a respective one prevailing suction air flow act as throttling sections.

LIST OF REFERENCE NUMBERS

1

boom

2

printing unit

2.1

pressure cylinder

2.2

Blanket cylinder

3

arc

4

chain conveyors

5

Direction arrow

6

conveyor chain

7

drive sprocket

8th

nose wheel

9

gripper system

9.1

grab

10

sheet guide

11

braking station

11.1; 11.2; 11.3

brake band

11.1 ', 11.2'; 11.3 '

cam

12

Leading-edge stop

13

Rear edge stop

14

stack

15

platform

16

lifting chain

17

sheet guide surface

18

Support

19

dryer

20

pollination device

21

inlet connection

22

outlet

23

Coolant tray

24, 24 ', 24' '

bowing

24.1; 24.1 '; 24.1 "

guide surface

24.2

down device

24.3; 24.3 '

endless band

24.4

role

24.5; 24.5 '

channel

24.6

suction opening

24.7; 24.7 '

squeegee

24.8

drilling

26

engine

27

engine

28

cam follower

29

lever

30

feather

31

cam

32

Vacuum generator

Claims (4)

1. A delivery means of a sheet-processing printing machine having grippers (9.1) which circulate during operation and transport the processed sheets (3) to a sheet brake (11) in a conveying direction (25) and transfer the sheets to the sheet brake (11) and with a first and a second sheet guide (24, 24', 24") a respective one of which acts on a respective lateral border of the sheets (3), as seen in the conveying direction (25),
   characterized in that the sheet guides (24; 24'; 24") guide the sheets (3) in a respective lateral region of the sheet brake (11, relative to the conveying direction (25), in contact with the sheet brake (11).
2. The delivery means as claimed in claim 1,
   characterized in that the sheet guides (24; 24'; 24") comprise the guide surfaces (24.1; 24.1'; 24.1") which support the lateral borders of the sheets (3) and against which the lateral borders of the sheets (3) can be pressed.
3. The delivery means as claimed in claim 2,
   characterized in that the lateral borders of the sheets (3) can be pressed against the guide surfaces (24.1'; 24.1") under the action of a pressure difference prevailing at the sheets (3).
4. The delivery means as claimed in claim 2,
   characterized in that the lateral borders of the sheets (3) can be pressed against the guide surfaces (24.1) by cyclically operated holding-down means (24.2).

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