EP0576810B1 - Installation for assisting the controlled transport of copies in the folder unit of rotary printing machines - Google Patents

Description

The invention relates to a device for supporting the controlled copy transport in the folder of rotary printing presses, in particular when reversing the transport direction of copies on copy-guiding cylinders.

DE 88 09 285.2 U1, in which a stationary suction chamber extends over the cylinder length, discloses a belt roll which is arranged in the cylinder winding of two folding cylinders. A disadvantage of this arrangement is the fact that two separate components are provided for deflection and for suction. Since high accelerations occur during the transition of the copies from the folding knife cylinder to the folding jaw cylinder, greasing of the copies on stationary components - here the suction chamber - cannot be ruled out at the resulting speeds of the copies.

No. 4,474,367 shows a sheet handling device with a hollow sheet transport drum which has a plurality of openings on the circumference. A vacuum source is also provided to create a partial vacuum inside the drum and a drive to rotate the drum. A stationary baffle plate is also associated with the outer drum surface. By means of a sliding element arranged in the sheet transport drum, circumferential areas of the sheet transport drum can be subjected to negative pressure and be separated from the negative pressure effect.
From EP 0220 644 B1 a device for the vacuum-guided guidance of folded copies is known. When the gap between a folding knife cylinder and a folding jaw cylinder passes, the copies of folding knives in Broken flaps pushed in. As the jaw cylinder from which the specimens are gripped rotates further, they are pulled over a freely rotatable suction-pressurized roller. Since this roller is not driven, a common movement of the specimen to be removed and the roller is achieved only via a frictional connection. The frictional connection between a freshly printed specimen surface and the roller jacket can lead to smearing on the product and to ink deposition on the roller jacket. The guide plates arranged on both sides of the freely rotatable roller also cause high relative speeds between the specimen to be removed and their surfaces, which is likewise unfavorable for gentle treatment of the specimen surfaces.

In a further development of the state of the art, the object of the invention is to optimize a device for supporting the controlled transport of specimens in such a way that the specimen transport always remains manageable even with processing speeds which are still to be increased.

According to the invention the object is solved by the features of claim 1.

This solution offers advantages in several ways. Since the cylinder circumferential speed prevails on the periphery of the drive of the guide means, speed differences between the specimen and the guide means are avoided. This prevents the paint from smearing. During the rotation of the guide means, a peripheral region of the guide means is always subjected to negative pressure, so that a specimen to be removed from a specimen-guiding cylinder can be guided continuously over the entire length of the specimen. As a result, corner turning can be excluded; uncontrolled movements of the specimens during their transport remain under. After the specimens have left the effective range of the negative pressure, they are picked up between the running strands of the conveyor belts and the surface of a folding jaw cylinder. Since in this transport section there are also no speed differences between the specimen and the contact surfaces of the running run on the one hand and between the specimen and the lateral surface of the folding jaw cylinder on the other hand, controlled product handling is guaranteed at all times in this critical transport section when the transport direction is reversed.

Treads for conveyor belts are provided on the suction roll jacket. The conveyor belts running on these running surfaces drive the suction roll jacket at the circumferential cylinder speed to eliminate speed differences. Furthermore, the specimens guided on the circumference of the suction roll shell can be taken over directly from running runs of the conveyor belts.

The vacuum chamber can be connected to a vacuum source that can be regulated in the volume flow in order to ensure that individual specimens are positioned correctly and securely on the circumference of the suction roll shell, depending on the substrate to be processed and the processing speeds to be driven. Furthermore, the vacuum chamber can be subdivided into at least two partial chambers by means of webs. When processing web strands with only half the width, this allows, for example, only half of the vacuum chamber to be subjected to negative pressure. If the web can be moved in the axial direction inside the vacuum chamber, the axial effective range can be adapted to different requirements.

If the diameter of the running surfaces of the suction roll shell changes, it is possible to advance or lag the suction roll shell relative to the circumferential speed of the cylinder holding the specimen. For this purpose, elastic rings can be mounted on the running surfaces to change the diameter of the running surfaces. The setting of the lead or lag of the suction roll shell relative to the cylinder peripheral speed can be particularly important for the processing of larger specimens brought together from several web strands.

Fig. 1

eine Seitenansicht der Sauwalzenachse,

Fig. 2

eine Vorderansicht der Saugwalzenachse,

Fig. 3

ein Schnitt durch Saugwalzenmantel und Saugwalzenachse, samt Vakuumkammer,

Fig. 4

die Einbaulage von Saugwalzenmantel auf der Saugwalzenachse mit auflaufenden und ablaufenden Transportbändertrums im Zwickel zweier exemplarführender Zylinder,

Fig. 5, 5a

das Bohrbild auf dem Saugwalzenmantel und

Fig. 5b

ein Querschnitt durch die Vakuumkammer

wiedergegeben sind.The invention is explained in detail below with reference to a drawing, wherein in

Fig. 1

a side view of the sowing roller axis,

Fig. 2

a front view of the suction roll axis,

Fig. 3

a section through the suction roll jacket and suction roll axis, including the vacuum chamber,

Fig. 4

the installation position of the suction roll jacket on the suction roll axis with rising and falling conveyor belt runs in the gusset of two exemplarizing cylinders,

5, 5a

the drilling pattern on the suction roll jacket and

Fig. 5b

a cross section through the vacuum chamber

are reproduced.

Figure 1 shows the side view of a suction roll axis. The suction roll axis 6 contains a vacuum chamber 6c which is delimited by the dashed lines. In the A nozzle receiving opening 5a is provided on the front side of the suction roller axis 6. Above the nozzle receiving opening 5a, a receiving piece 6a is provided, with which the suction roll axis 6 is received in a holder.

Figure 2 shows the front view of a suction roll axis. In this view it can be seen that the nozzle receiving opening 5a extends all the way to the vacuum chamber 6c. The end face area which is penetrated by the nozzle receiving opening 5a, in cooperation with a suction roll jacket 7, serves as a gap seal for sealing the vacuum chamber 6c. Consequently, there is no need for co-rotating sealing elements which are susceptible to wear and contamination at the boundaries of the vacuum chamber 6c.

FIG. 3 shows a section through the suction roll jacket and suction roll axis together with the vacuum chamber. In a boundary wall 1, a bracket 2 is received via a screw 3. In this holder a locking screw 4 is received, which engages in the thread made in the receiving piece 6a. The receiving piece 6a is provided with a concave recess, which allows a suction air line to be placed on an air connection 5. The air connection 5 is received in the socket opening 5a of the suction roll axis 6 and connects a vacuum source which can be regulated in the air volume flow to the vacuum chamber 6c. A bearing 6b is also accommodated on the suction roller axis 6 and rotatably supports the suction roller shell 7 on the suction roller axis 6. The bearing is axially secured via circlips 7c. The suction roll jacket 7 is provided on its circumference both with annular treads 7b forming depressions and with annular thickenings in which the bores 7a are made. As can be seen from Figure 3, thickenings and Indentations in the axial direction on the circumference of the suction roll shell 7 alternately. Conveyor belts run in the depressions forming the running surfaces 7b in the circumference of the suction roll shell 7 and set the suction roller shell 7 in rotation relative to the suction roller axis 6. Since the suction roller shaft 6 and suction roller shell 7 have a very slim design, a rapid build-up of the negative pressure in the vacuum chamber 6c is ensured at the individual bores 7a of the suction roller shell 7.

In the context of an automatic presetting to the web width to be processed, it would be possible to mount a web made of plastic with the dimensions corresponding to the vacuum chamber on a threaded spindle extending through the vacuum chamber 6c. The web can now be moved in the axial direction by means of a remote-controlled servomotor, so that only a region of the vacuum chamber 6c determined by the web position can be subjected to negative pressure. The vacuum distribution on the suction roll jacket 7 can thus be adapted to the printing material formats to be processed within the framework of the presetting on the folder.

FIG. 4 shows the installation position of the suction roll jacket on the suction roll axis with the infeed and outfeed conveyor belt runs in the gusset of two exemplarizing cylinders. The bracket 2 received on the machine wall side receives the receiving piece 6a of the suction roller axis 6 via the locking screw 4. Vacuum chamber 6c is subjected to negative pressure via air connection 5. Conveyor belts 12, which set the suction roll casing 7 in rotation, run on the depressions shown in dashed lines on the suction roll casing 7. The drive is initiated by the traction strand 12b in accordance with the cylinder circumferential speed of the cylinder 9 carrying the exemplar; the train strand 12b of the conveyor belts lies on the surface of the cylinder 9 carrying the copy and conveys the copy 13. The runs running onto the suction roll jacket 7 are designated by 12a.

The specimen 13, which is also separated from a web strand formed from several layers, is received on the specimen-guiding cylinder 8, the folding knife cylinder, and is conveyed out of the cylinder gusset 10 in the direction of the arrow. Folding knives, not shown here, have pushed the specimen - for example in the center - into a folding flap of the specimen-carrying cylinder 9, also not shown. The specimen 13 is withdrawn from the specimen-guiding cylinder 9, the folding jaw cylinder, against its original transport direction - indicated by the direction arrow in the specimen-guiding cylinder 8 - by the rotation of the specimen-guiding cylinder 9 in the direction of the arrow during the transfer. Fluttering or cornering of the specimen 13 is avoided by the product guide 11 above the specimen 13 to be removed. By acting on the vacuum chamber 6c in the suction roll axis 6, the copy 13 gripped by the copy-guiding cylinder 9 on the fold back is sucked in. Since the suction roll jacket 7 rotates at the circumferential cylinder speed, speed differences are eliminated. Since the vacuum in the vacuum chamber 6c is continuously present and the specimen 13 is conveyed by the rotating suction roll jacket 7, the specimen 13 moves in full length past the vacuum chamber 6c to which vacuum is applied and is sucked in by the latter. After passage of the circumferential segment acted upon by the contour of the vacuum chamber 6c, the specimens 13 get between the surface of the specimen-guiding cylinder 9 and the surfaces of the traction strand 12b of the conveyor belts 12 facing the specimens 13. Since these move at the circumferential cylinder speed, the specimens 13 are here not exposed to any friction and shear stress. The - as can be seen in Figure 4 - between the train runs 12b and the cylinder surface of the specimen-carrying cylinder 9-conveyed specimens 13 can now be processed further on the jaw cylinder. In this way, when the transport direction of specimens 13 is reversed, their surfaces are subject to continuous guidance when changing from one to the other of the specimen-guiding cylinders 8 and 9, which permits high and highest specimen processing speeds.

Figures 5 and 5a show the drilling pattern of the suction roll shell. The holes 7a made in annular thickenings on the suction roll jacket 7 have counterbores. The drilling pattern shows that a staggered arrangement of the individual bores 7a in relation to one another enables a high occupancy density of the annular thickenings to be achieved. This ensures reliable suction of the specimens 13 even at high speeds.

FIG. 5b shows a cross section through the vacuum chamber 6c. The leg of the vacuum chamber 6c extending to the left marks the beginning of the suction zone on the circumference of the suction roll shell 7 rotating on the suction roll axis 6. The leg of the boundary of the vacuum chamber 6c extending to the right marks the end of the suction zone on the circumference of the suction roll axis 6 rotating suction roll shell 7. Due to the position of the limits of the vacuum chamber 6c, the suction zone can be varied over the circumference of the suction roll shell 7, whereby individual requirements can be taken into account. In the present position of the vacuum chamber 6c and the suction roll jacket 7 relative to one another, the lower bores 7a made in the suction roll jacket 7 are in contact with the vacuum chamber 6c, while the upper bores 7a are separated from the suction air source.
There is a minimal gap between the surface of the suction roller axis 6 and the inner surface of the suction roller shell 7 provided to allow smooth rotation of the suction roll shell 7. This gap is designed in the axial delimitation area of the vacuum chamber 6c as a contactless gap seal. Sealing of the vacuum chamber 6c can thus be achieved; the leakage losses remain negligible.

REFERENCE SIGN LIST

1

Boundary wall

2nd

bracket

3rd

Screw connection

4th

Locking screw

5

Air connection

5a

Port opening

6

Suction roll axis

6a

Recording piece

6b

camp

6c

Vacuum chamber

7

Suction roll jacket

7a

Holes

7b

Tread

7c

Circlip

8th

exemplary cylinder

9

exemplary cylinder

10th

Cylinder gusset

11

Product management

12th

Conveyor belts

12a

emerging runs

12b

Train run

13

copy

Claims (5)

1. Device for guiding copies (13) in the folder of rotary printing machines between copy-guiding cylinders (8, 9), wherein, to assist the reversal of the transporting direction, the copies (13) bear against a guiding means (7) which extends over the length of copy-guiding cylinders (8, 9), can be driven by transport belts (12) and is held rotatably on a body (6), and negative pressure is produced between the copy (13) and the guiding means (7), characterized in that a vacuum chamber (6c) in a suction roller axis (6), facing a cylinder gore (10) between the copy-guiding cylinders (8, 9), subjects the guiding means (7) rotating on the suction roller axis (6) to negative pressure during the transfer of the copies (13), without relative speed, from the surface of the first copy-guiding cylinder (8) to the surface of the second copy-guiding cylinder (9), the range of action of the negative pressure being adjustable in the axial direction of the vacuum chamber (6c) by means of webs.
2. Device according to Claim 1, characterized in that the vacuum chamber (6c) is connected to a source of negative pressure which can be regulated in the flow volume of suction air.
3. Device according to Claim 1, characterized in that the vacuum chamber (6c) can be subdivided by webs into at least two partial chambers.
4. Device according to Claim 1, characterized in that a lead or lag of the casing (7) of the suction roller relative to the circumferential speed of the copy-guiding cylinders (8, 9) can be achieved by changing the diameter of running surfaces (7b) on the casing (7) of the suction roller.
5. Device according to Claim 4, characterized in that elastic rings can be mounted on the running surfaces (7b) to change the diameter of the running surfaces (7b).

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