CN109624499B

CN109624499B - Printing machine with a turning mechanism and a guide mechanism

Info

Publication number: CN109624499B
Application number: CN201811138558.0A
Authority: CN
Inventors: A·云格尔; P·托马; S·穆沙尔
Original assignee: Heidelberger Druckmaschinen AG
Current assignee: Heidelberger Druckmaschinen AG
Priority date: 2017-10-06
Filing date: 2018-09-28
Publication date: 2022-02-22
Anticipated expiration: 2038-09-28
Also published as: CN109624499A; DE102018215386A1

Abstract

The invention relates to a printing press comprising a turning mechanism (1) having a storage cylinder (2) and a turning cylinder (3), and comprising a guide mechanism arranged beside the turning mechanism for guiding a sheet (7), wherein a wedge (16) is located between the storage cylinder (2) and the turning cylinder (3). The guide mechanism has a support means which supports the sheet (7) on its sheet side facing the wedge (16) if the sheet (7) is already gripped by the turning cylinder (3) during turning, wherein the support means supports the sheet (7) in the wedge (16). The support means may be configured, for example, to support the slider, to support the rotor or to support the flap.

Description

Printing machine with a turning mechanism and a guide mechanism

Technical Field

The invention relates to a printing press comprising a turning mechanism having a storage cylinder and a turning cylinder, and comprising a guide mechanism arranged laterally to the turning mechanism for guiding a sheet, wherein a wedge (Zwickel) is arranged between the storage cylinder and the turning cylinder.

Background

This printing machine is called a perfecting machine (perfecttor) and is capable of printing both the front and the back in one pass (in einem Durchlauf). In this case, the sheets are printed on their front side in one or more printing couples upstream of the turning mechanism and on their rear side in one or more printing couples downstream of the turning mechanism. The tilting mechanism operates according to the principle of the so-called trailing edge tilting (hinderkantenwendung).

DE 10143098B 4 describes a device for guiding and conveying sheets, in which a retaining element is guided by a guide device, which is held outside a first and a second drum.

DE 10340171B 4 describes a sheet guide for sheets in the area of a turning mechanism, which is arranged on the side of a common tangent line extending from a transfer cylinder to the turning cylinder, wherein the sheet guide has at least one suction means in the area below the storage cylinder.

Document DE 4030070 a1 describes a sheet storage unit on a sheet-fed rotary printing press which can be used for recto printing or recto and verso printing in an alternative manner. In order to guide the sheet during the turning process, a suction for receiving the sheet is arranged in a rotating manner on the endless track.

DE 102006032922B 3 describes a mechanism for supporting sheet guidance in a printing press which can be used for recto printing or recto and verso printing in an alternative manner. In this case, a sheet wiping mechanism is provided in the peripheral region of the drum, which presses the turned sheet away from the periphery of the drum.

Disclosure of Invention

The aim of the invention is to provide a printing press with a turning mechanism and a guide mechanism, by means of which the sheets are effectively calmed (beruhigt) and are held on their nominal path.

This object is achieved by a printing press comprising: a turnover mechanism having a storage drum and a turnover drum; and a guide mechanism arranged beside the turning mechanism for guiding the sheet, wherein the wedge is located between the storage cylinder and the turning cylinder, and the printing press according to the invention is characterized in that the guide mechanism has a support device: if the sheet is already gripped by the turning cylinder during turning (elevator), the support means support the sheet on the side of the sheet facing the wedge (bogeseite), wherein the support means support the sheet inside the wedge.

The advantage of the printing press according to the invention is that the support means can reach the page side of the page which has not yet been printed and are supported thereby, wherein the support means form a height stop

The height stop prevents the sheet from deviating upward from its nominal trajectory during a turn.

The printing press according to the invention is particularly well suited for processing thin sheets with a low grammage (e.g. thin printing sheets), since such sheets tend to run unstably (e.g. flutter) when turned over and are difficult to stabilize by conventional measures.

In a development of the printing press according to the invention, the support elements can be moved into the wedge in a periodic (period) manner.

The supporting elements can overlap the side of the page that points toward the wedge in the active position, but do not overlap the side of the page in the release/passive position (pasivposition) of the supporting elements.

In the activated position, the support elements can project from both lateral edges of the sheet into the wedge.

The support means can have support surfaces on which the supported sheet slides.

These support surfaces can be configured as suction surfaces, for example with nozzles. The support elements can thus hold the sheet pneumatically by means of vacuum. For this purpose, these support means may be attached to the air extractor.

In this case, the laterally outer nozzles of the respective suction surface can be smaller in flow cross section than the inner nozzles (i.e., closer to the sheet center), so that these laterally outer nozzles have a stronger throttling effect. Since the sheet is usually inevitably loose (Durchhang) in its center (with reference to the sheet width), these outer nozzles may not coincide with the page-side edges, wherein without countermeasures there is the risk of excessive false air suction.

This risk can be effectively addressed by configuring these external nozzles as throttling nozzles.

These support surfaces can be configured as wedge surfaces

In this case, the support surfaces can be tapered in the direction of movement of the support means (anseigen).

These support means can be configured to support the slider, to support the flap or to support the rotor.

Drawings

Advantageous refinements also result from the following description of the embodiments and the associated drawings, which show:

FIG. 1: a turnover mechanism of the sheet rotary press;

FIG. 2: a general side view of the turning mechanism of fig. 1 with associated sheet support means, which are designed to support the flap;

FIG. 3: fig. 2 is a single front view of the support flap;

FIG. 4: a general side view of the turning mechanism of fig. 1 with associated alternative sheet support means configured to support the rotor;

FIG. 5: FIG. 4 is a single top view of the support rotor;

FIG. 6: a general side view of the turning mechanism of fig. 1 with associated alternative sheet support means, which are designed as support sliders; and

FIG. 7: fig. 6 shows a modification of the support slides, wherein the support slides are extended for sheet support in a format-wide manner.

Elements or components corresponding to each other in fig. 1 to 7 are denoted by the same reference numerals.

Detailed Description

Fig. 1 shows a turning mechanism 1 of a printing press. The turning mechanism 1 comprises a storage cylinder 2 and a turning cylinder 3, the storage cylinder 2 and the turning cylinder 3 being arranged between a transfer cylinder 4 and a corresponding printing cylinder 5. The printing press is a perfecting printing press and can be set from a front-side printing mode to a front-side and a back-side printing mode by means of a turning mechanism 1. The reversing cylinder 3 is half as large as the storage cylinder 2 and is disposed downstream of the storage cylinder 2 in the sheet conveying direction. The gripper 6 of the reversing cylinder 3 holds the sheet 7 at its rear edge by clamping during the reversing. The tilting mechanism 1 operates in a front-side and a rear-side printing mode according to the principle of so-called trailing edge tilting.

The gripper 6 can be pivoted from a first position 6.1 into a second position 6.2 relative to the tumble drum 3. In the first position 6.1, the reversing cylinder 3 grips the trailing edge of the sheet 7 on the storage cylinder 2. In the second position 6.2, the reversing cylinder 3 tensions the sheet 7 along the connecting tangent of the cylinders 2, 3, the opposite sheet edge of the sheet 7 also being located on the storage cylinder 2. The movement phases of the sheet 7 between these positions 6.1, 6.2 are shown together in the drawing. In order to stabilize the sheet section that is not under tension, a guide is provided, which is not shown in fig. 1.

A first variant of the guide mechanism is shown in fig. 2 and 3. Furthermore, a blower 8 arranged below the drums 2, 3 for guiding the sheet 7 by means of blowing air is shown, as well as a suction 9 of the storage drum 2, which suction 9 serves to hold the sheet 7 in the region of a sheet edge of the sheet 7 resting on the suction 9. The blower 8 and the aspirator 9 are also present in all other embodiments.

The guide mechanism comprises a respective support flap 10 on the drive side and on the operating side of the printing press (i.e. to the right and to the left of the sheet (7) in the transport direction). Each support flap 10 is pivotable about a hinge 11 having a geometric axis 12, which geometric axis 12 is oriented parallel to the lateral edges 15 of the sheet section to be stabilized. The supporting flaps 10 are fixed to the side walls 13 of the machine frame by means of the hinges 11. Each support flap 10 has a support surface 14, which support surface 14 is configured as a suction surface with a nozzle. The supporting flaps 10 are moved in a sheet-conveying cycle by means of individual drives or by means of a common drive

The activation position 10.1 and the release position 10.2 can be pivoted in a cyclic manner. In this case, the support flaps 10 are tilted to and fro synchronously with one another, but in opposite directions, as is indicated by the double arrow in fig. 3. The respective support surface 14 is opposite the sheet 7 in the active position 10.1 and is not opposite it in the release position 10.2.

In the active position 10.1, the respective support flap 10 fits into a wedge 16, which is triangular for example, and which wedge 16 is formed by the rollers 2, 3 and the sheet 7, and the support surface 14 is in contact with the sheet 7 on the unprinted side of the sheet 7, which side faces the inside of the wedge 10. The sheet 7 is supported by a support flap 10 in the region of the section of the sheet 7 which extends generally freely between the rollers 2, 3. In this case, the sheet 7 slides on the support surfaces 14, and the support surfaces 14 catch the sheet 7, as a result of which the sheet 7 is tensioned against its transport direction. For this purpose, these support flaps 10 are attached to the air extractor by means of pipelines.

At least one of the fans 8 is oriented in such a way that its blowing air presses the sheet 7 against the support flap 10, in order to reinforce the friction between the sheet 7 and the support flap 10 required for sheet tensioning from the other page side.

Fig. 4 and 5 show a second variant of the guide mechanism, in which a respective support rotor 17 is provided on the drive side and on the operating side. Each support rotor 17 rotates about a rotary bearing 18 having a geometric axis 19, the geometric axis 19 being oriented transversely or orthogonally to the lateral edges 15 of the sheet section to be stabilized. The two support rotors 17 are driven by their own drive or by a common drive and rotate in opposite directions to each other: one in clockwise and the other in counterclockwise direction. Each support rotor 17 rotates at a constant rotational speed with a constant printing speed. The rotation speed of these support rotors 17 is varied proportionally to the variation in printing speed by corresponding actuation of one or more actuators.

The rotational angle position of the support rotors 17 is synchronized with the sheet transport cycle, so that the support surfaces 20 of the support rotors 17 always sink into the wedge 16 from both sides when the wedge 16 is spanned by the sheet 7, as can be seen in fig. 4. The upper support rotor 17 according to fig. 5 shows an activation position 17.1 and the lower support rotor 17 shows a release position 17.2, wherein both support rotors 17 are in their respective activation positions 17.1 and in their respective release positions 17.2 simultaneously during a printing run, without the hypothetical situation according to fig. 5, which is merely for explanation.

In the active position 17.1, the respective support surface 20 is opposite the sheet 7 and is in sliding contact with the side thereof which has not yet been printed (reverse printing side). The support surfaces 20 are located on the respective sector wings of the support rotor 17.

The support surface 20 does not extend around the axis 19 orthogonally to the axis 19, but has a pitch-like lift (antistieg), so that the support surface 20 is a wedge-shaped surface. Due to the lift of the bearing surface 20, the front edge 21 of the supporting rotor 17 is thinner than the rear edge 22. As a result, the spacing between the support surface 20 and the unprinted sheet side decreases as the number of sheets 7 that are overlapped by the support rotor 17 increases during rotation of the support rotor 17. The risk of the leading edge 21 hitting the lateral edge 15 of the sheet is not present even in the case of shaking and vibrations of the sheet section to be supported, because: when the leading edge 21 moves past the lateral edge 15 and overlaps the sheet 7, the leading edge 21 is outside the possible vibration region of the lateral edge 15 due to the wedge surface.

The respective support surface 20 supporting the rotor 17 is configured as a suction surface and has an array of suction nozzles 23. The suction nozzles 23 hold the sheet 7 on the support surface 20 while the sheet 7 slides on the support surface 20. The sheet 7 is tensioned in its longitudinal and transverse directions. This longitudinal tension is produced by the relative movement between the sheet 7 and the support rotor 17. In this case, this relative movement is caused on the one hand by the sheet 7 being transported past the stationary support rotors 17 in the transport direction 24 and on the other hand by a component of the rotational movement of the individual support rotors 17 holding the sheet 7 in a pneumatically fixed manner, which component is oriented counter to the transport direction 24. The transverse tension of the sheet 7 is produced by further movement components of the support rotor 17, which are directed perpendicular to the conveying direction 24 toward such a side edge 15 of the sheet 7: the lateral edges 15 are associated with the respective support rotor 17. In the case of transverse tensioning, the two support rotors 17 tension the sheet 7 from the inside to the outside in opposite directions. In a second variant of the guide mechanism, the sheet 7 is not only sucked onto the support surface 20, but is pushed against the support surface 20 by blowing air from one or more blowers 8.

In fig. 6 and 7, embodiments are shown in which a support slider 25 is provided instead of supporting the flap 10 (see fig. 2 and 3) or supporting the rotor 17 (see fig. 4 and 5). The two support sliders 25 perform a reciprocating motion in a periodic manner, close to and away from each other, at the sheet transfer cycle. In this reciprocating movement, the support sliders 25 reach into the wedge 16 and support the sheet 7 there on the side of the sheet 7 facing the wedge 16. The linear reciprocating movement of the support sliders 25 is effected in a direction parallel to the axis of rotation of the cylinders 2, 3 and thus orthogonal to the conveying direction 24 of the sheets 7. By this reciprocating movement, the two support sliders 25 reach their active position simultaneously and overlap the sheet 7 within the wedge 16. The activated position of these support sliders 25 is shown in fig. 6 and 7, while the deactivated position without overlap is not shown.

The support sliders 25 have a respective support surface 26, on which support surface 26 the sheet 7 supported thereon slides. The support surface 26 faces the reverse printing side of the sheet and is configured as a suction surface. The linear guides for guiding the support rail 25 and the drive or drives for moving the support slide 25 are not shown together in the figures.

In their active position, these support sliders 25 in the example in fig. 6 overlap only the lateral edge regions of the sheet 7 and in the example in fig. 7 overlap a large part of the format width (format) of the sheet 7. The support surfaces 26 can have a chamfer on the end of the support slide 25 facing the sheet 7 or can be designed as a wedge surface in order to avoid a collision with the lateral edges 15 of the sheet 7 when pushed into the wedge 16.

List of reference numerals:

1 turnover mechanism

2 storage roller

3 turnover drum

4 transfer roller

5 corresponding printing rotary drum

6 gripping apparatus

6.1 first position

6.2 second position

7 pages

8 blower

9 suction device

10 support flip

10.1 activation position

10.2 Release position

11 hinge part

12 axes of rotation

13 side wall

14 support surface

15 side edge

16 wedge-shaped part

17 support the rotor

17.1 activation position

17.2 Release position

18 swivel bearing

19 axis line

20 bearing surface

21 front edge

22 rear edge

23 suction nozzle

24 direction of conveyance

25 support slide block

26 bearing surface

Claims

1. A printing press, comprising:

-a turning mechanism (1) with a storage drum (2) and a turning drum (3), and

a guide mechanism arranged beside the turning mechanism for guiding the sheet (7),

wherein the printing press is a perfecting printing press and can be set from a front-side printing mode to a front-side and a back-side printing mode by means of the turning mechanism (1), wherein a wedge (16) is provided between the storage cylinder (2) and the turning cylinder (3),

it is characterized in that the preparation method is characterized in that,

the guide mechanism has a support means which, when the sheet (7) has been gripped by the turning cylinder (3) during turning, supports the sheet (7) on the still unprinted reverse printing side of the sheet which is directed toward the wedge (16),

wherein the support means support the sheet (7) inside the wedge (16).

2. The printing press as set forth in claim 1,

it is characterized in that the preparation method is characterized in that,

the support means can be moved into the wedge (16) in a periodic manner.

3. A printing press according to claim 1 or 2,

it is characterized in that the preparation method is characterized in that,

the support means in the activated position (10.1, 17.1) overlaps the reverse printing side which points into the wedge (16) and in the deactivated position (10.2, 17.2) does not overlap.

4. The printing press as set forth in claim 3,

it is characterized in that the preparation method is characterized in that,

in the active position (10.1, 17.1), the support means project from both lateral edges (15) of the sheet (7) into the wedge (16).

5. A printing press according to claim 1 or 2,

it is characterized in that the preparation method is characterized in that,

the support means have a support surface (14) on which the supported sheet (7) slides.

6. A printing press according to claim 5, wherein,

it is characterized in that the preparation method is characterized in that,

the support surface (14) is designed as a suction surface.

7. A printing press according to claim 5, wherein,

it is characterized in that the preparation method is characterized in that,

the support surface (14) is designed as a wedge surface.

8. A printing press according to claim 1 or 2,

it is characterized in that the preparation method is characterized in that,

the support means are configured to support a slider (25).

9. A printing press according to claim 1 or 2,

it is characterized in that the preparation method is characterized in that,

the support means is configured to support the flap (10).

10. A printing press according to claim 1 or 2,

it is characterized in that the preparation method is characterized in that,

the support means is configured to support a rotor (17).