EP4282657B1 - Folding apparatus of an offset web-fed printing press and offset web-fed printing press - Google Patents

Description

The invention relates to a folding apparatus of an offset web printing press. Furthermore, the invention relates to an offset web printing press.

Offset printing units of an offset web printing machine are used to print a web-shaped printing material with a fixed printing format. The cylinders of an offset printing unit of an offset web printing machine are designed for a fixed printing format. If a printing material with a different printing format is to be printed on an offset web printing machine, different offset printing units with different printing formats must be available. When executing a print job with a defined printing format, only offset printing units with the same printing format are used for printing. After completing a print job with a defined printing format, the offset printing units used for printing can then be changed to execute a new print job with a new printing format.

An offset web printing press has a folding device to produce printed products. The basic structure of a folding device on an offset web printing press is known from practice. A folding device on an offset web printing press has at least one cutting device to separate individual signatures from a printed, web-shaped printing material. Before the signatures are separated, a longitudinal fold can be formed on the still web-shaped printing material in the area of a folding former. Alternatively and additionally, a cross fold can be made on separated signatures in the area of a cross folding device and/or a longitudinal fold can be made in the area of a longitudinal folding device.

In practice, the folding device of an offset web printing press is adapted to the format of the offset printing units. If an offset web printing press has offset printing units with different printing formats, the offset web printing press also has several folding devices in order to further process the printing formats printed with the different offset printing units into printed products in the area of each folding device.

Digital web printing presses are different from offset web printing presses. Digital web printing presses do not print with fixed printing forms and therefore fixed printing formats, but rather without printing forms and with variable printing formats. Folding devices for digital web printing presses are known from the state of the art and provide a certain degree of format variability on a digital web printing press.

EN 10 2012 103 729 A1 discloses a folding device of a digital web printing machine with a cutting device, via which signatures can be separated from a printed substrate. A longitudinal folding device is arranged upstream of the cutting device. Signatures separated from the web-shaped substrate in the area of the cutting device are accelerated to the peripheral speed of a collecting cylinder using an acceleration device. Cross folds can be made on the separated signatures in the area of a folding jaw cylinder and longitudinal folds can be made in the area of another longitudinal folding device. In the area of the cutting device, signatures can be separated from the printed substrate in a variable format, i.e. with different section lengths.

EP 1 209 000 B1 discloses a method for producing newspapers on a digital printing machine with two folding stations and two collecting stations. JP2019210140 also reveals a folding device.

There is a need for a format-variable folding device for an offset web printing press.

Based on this, the present invention is based on the object of creating a format-variable folding device for an offset web printing machine. Furthermore, the invention is based on the object of creating an offset web printing machine with such a folding device.

The object is achieved by a folding apparatus of an offset web printing machine according to claim 1.

The folding apparatus of an offset web printing machine according to the invention has a first transport device designed as a belt guide system for a web-shaped printing material. The first transport device is set up in such a way that belts thereof can be driven at a speed that corresponds to the speed of the web-shaped printing material.

The folding apparatus of an offset web printing machine according to the invention further comprises a first cutting device arranged in the region of the first transport device. The first cutting device is designed in such a way that it cuts the web-shaped printing material in a format-variable manner in those sections that are not covered by the belts of the first transport device.

The folding apparatus of an offset web-fed printing machine according to the invention further comprises a second transport device arranged downstream of the first transport device and designed as a belt guide system, the belts of which are offset transversely to the transport direction of the printing material relative to the belts of the first transport device, wherein the second transport device is designed such that belts thereof can be driven at a speed which is greater than the speed of the belts of the first transport device.

The folding apparatus of an offset web-fed printing machine according to the invention further comprises a second cutting device arranged in the region of the second transport device, wherein the second cutting device is designed such that, in order to separate signatures, it cuts the web-shaped printing material in a format-variable manner in those sections which are covered by the belts of the first transport device.

The folding apparatus of an offset web-fed printing machine according to the invention further comprises a signature accelerator in order to accelerate the signatures separated from the web-shaped printing material from the speed of the belts of the first transport device to the speed of the belts of the second transport device.

The folding apparatus of an offset web-fed printing machine according to the invention has the first transport device and the second transport device, which are each designed as belt guide systems. The belts of the second belt guide system are offset from the belts of the first belt guide system, viewed transversely to the transport direction of the web-shaped printing material.

The first cutting device is arranged in the area of the first transport device and the second cutting device is arranged in the area of the second transport device. The two cutting devices together cut the printing material across the entire width of the material across the transport direction in a format-variable manner, namely the first cutting device in those areas that are not covered by the belts of the first transport device and the second cutting device in those areas that are not covered by the belts of the second transport device, but are covered by the belts of the first transport device.

The belts of the second transport device have a higher speed than the belts of the first transport device. In the area of the first transport device, the speed of the belts corresponds to the speed of the web-shaped printing material. In the area of the second transport device, the signature accelerator accelerates signatures separated from the web-shaped printing material to the speed of the belts of the second transport device. The speed of the web-shaped printing material upstream of the second cutting device is lower than the speed of the belts of the second transport device.

The folding apparatus of an offset web-fed printing machine according to the invention allows a reliable, format-variable separation of signatures from the web-shaped printing material in the area of the first and second cutting device, a reliable guidance of the printing material and the signatures in the area of the first and second transport device and an acceleration of the signatures from the speed of the first transport device to the speed of the second transport device.

The folding apparatus according to the invention is used on an offset web printing machine that has at least two offset printing units that differ in terms of their printing format. The folding apparatus according to the invention makes several folding apparatuses that are designed for different printing formats on offset printing units superfluous.

Preferably, in order to provide format variability, the first transport device is configured such that, for the same number of signatures to be processed per unit of time, the speed of the belts of the first transport device is lower the smaller or shorter the length of the signatures is.

Preferably, in order to provide format variability, the signature accelerator is designed such that it accelerates the signatures from the speed of the belts of the first transport device to the speed of the belts of the second transport device the shorter the length of the signatures. Furthermore, in order to provide format variability, a relative position of the signature accelerator to the second cutting device can be set in a format-variable manner such that the distance between the signature accelerator and the second cutting device in the transport direction of the signatures is smaller the shorter the length of the signatures.

The format variability can be provided in a particularly advantageous manner by the above features. The speed of the belts of the first transport device as well as the acceleration of the signatures by the signature accelerator and the distance of the signature accelerator from the second cutting device can be adjusted to suit the format.

Preferably, the first cutting device and the second cutting device are designed as cutting cylinders and can be driven in such a way that when the respective format-variable cut is carried out, a peripheral speed of the respective cutting cylinder corresponds to the speed of the web-shaped printing material, regardless of the length of the signatures. This also makes it particularly advantageous to ensure format variability.

Furthermore, this object is achieved by an offset web printing machine according to claim 14.

Fig. 1:

eine Seitenansicht eines Ausführungsbeispiels eines Falzapparats einer Offset-Rollendruckmaschine;

Fig. 2:

einen Ausschnitt aus dem Falzapparat der Fig. 1,

Fig. 3:

einen Ausschnitt aus dem Falzapparat der Fig. 1 in Blickrichtung III der Fig. 1, und

Fig. 4:

eine Seitenansicht eines Ausführungsbeispiels einer Offset-Rollendruckmaschine.

Preferred developments of the invention emerge from the dependent claims and the following description. Exemplary embodiments of the invention are explained in more detail with reference to the drawing, without being limited thereto. In this drawing:

Fig.1:

a side view of an embodiment of a folding apparatus of an offset web printing press;

Fig. 2:

a section of the folding machine of the Fig.1 ,

Fig. 3:

a section of the folding machine of the Fig.1 in viewing direction III of the Fig.1 , and

Fig.4:

a side view of an embodiment of an offset web printing machine.

The invention relates to a folding apparatus of an offset web printing machine.

Fig.1 shows an embodiment of a folding apparatus 10 of an offset web printing machine designed as a book folding apparatus. As will be described below, in the area of a book folding apparatus, signatures are separated from a printed printing material web, collected into signature stacks and longitudinal folds are formed on the signature stacks. Although the invention can be used particularly advantageously in a folding apparatus designed as a book folding apparatus, the invention is not limited to this application.

The folding device 10 of the Fig.1 has a first transport device 11, which is designed as a first belt guidance system.

The first transport device 11, designed as a first belt guide system, serves to convey a web-shaped, printed printing material 12 in the area of the folding apparatus 10, wherein the first transport device 11 is set up such that belts 13 of the first transport device 11 can be driven at a speed that corresponds to the speed of the web-shaped printing material.

For this purpose, the first transport device 11 has a drive motor 14 which drives the belts 13 of the first transport device 11 in such a way that the speed of the belts corresponds to the speed of the web-shaped printing material 12.

The folding apparatus 10 has a first cutting device 15, which is arranged in the area of the first transport device 11 designed as the first belt guide system. The first cutting device 15 is set up in such a way that it cuts the web-shaped printing material 12 in a format-variable manner in those areas that are not covered by the belts 13 of the first transport device 11.

In the embodiment shown, the first cutting device 15 has a cutting cylinder 16 with cutting blades, which interacts with a counter cylinder 17. The cutting blades of the cutting cylinder 16 are interrupted at the positions at which the belts 13 of the first transport device 11 cover the web-shaped printing material.

The folding apparatus 10 has a second transport device 18 designed as a second belt guide system downstream of the first transport device 11. Belts 19 of the second transport device 18 are offset from the belts 13 of the first transport device 11, seen transversely to the transport direction of the transport devices 11, 18, so that the belts 19 of the second transport device 18 release those sections of the printing material 12 that are covered by the belts 13 of the first transport device 11 in the area of the first transport device 11. The belts 19 of the second transport device 18 can be driven by a drive motor 20 in such a way that they are driven at a speed that is greater than the speed of the belts 13 of the first transport device 11.

A second cutting device 21 is arranged in the area of the second transport device 18. The second cutting device 21 is designed so that, in order to separate signatures from the web-shaped printing material 12, it cuts the latter in a format-variable manner in those areas that are covered by the belts 13 of the first transport device 11 in the area of the first transport device 11 and thus of the first cutting device 15.

The second cutting device 21 cuts through the web-shaped printing material 12 in those areas where the web-shaped printing material 12 is not cut through in the area of the first cutting device 15.

In the area of the second cutting device 21, the format-variable partial cut of the first cutting device 15 is therefore completed in order to separate signatures from the web-shaped printing material in a format-variable manner.

The first cutting device 15 and the second cutting device 21 are synchronized in such a way that their format-variable cuts are aligned transversely to the transport direction of the printing material 12, thus resulting in a continuous cut across the width of the printing material.

In the embodiment shown, the second cutting device 21 is also formed by a cutting cylinder 22 and a counter cylinder 23 that interacts with the cutting cylinder 22. The cutting cylinder 22 of the second cutting device 21 carries cutting blades that are interrupted in the area of the belts 19 of the second transport device 18.

In Fig.3 the counter cylinders 17, 23 are arranged behind the cutting cylinders 16, 22, i.e. are covered by them.

Fig.3 shows drive motors 24, 25 for the two cutting cylinders 16, 22 of the two cutting devices 15, 21 in order to drive the cutting cylinders 16, 22. The counter cylinders 17, 23 of the cutting devices 15, 21 are also assigned such drive motors in order to drive them. The drive motors serve to dynamically drive the cylinders 15, 22, 17, 23 in order to produce the format-variable section lengths.

As already explained, the speed of the belts 13 of the first transport device 11 corresponds to the speed of the web-shaped printing material. The speed of the belts 19 of the second transport device 18 is greater than the speed of the belts 13 of the first transport device 11, whereby in the embodiment shown the speed of the belts 19 of the second transport device 18 corresponds to the peripheral speed of a signature collecting cylinder 26 arranged in the area of the second transport device 18.

In the area of the signature collection cylinder 26, signatures separated from the web-shaped printing material 12 can be collected in a variable format to form signature stacks. These signature stacks are transferred to a signature cylinder 27 downstream of the signature collection cylinder 26 and, starting from this signature cylinder 27, are conveyed via a transport device 28 in the direction of a longitudinal folding device 29 in order to form longitudinal folds on the signature stacks.

In order to accelerate signatures separated from the web-shaped printing material 12 to the speed of the belts 19 of the second transport device 18, the folding device 10 also comprises a signature accelerator 30. The signature accelerator 30 is installed in the area of the second transport device 18, directly adjacent to the second cutting device 21, in the area of which the signatures are separated from the web-shaped printing material 12. Upstream of the second cutting device 21, the signatures are not yet completely separated from the web-shaped printing material 12.

The second cutting device 21, which is synchronized with the first cutting device 15 and serves to complete the separation of the signatures from the web-shaped printing material 12, is arranged immediately adjacent to a transfer area 31 between the first transport device 11 and the second transport device 18 in the area of the second transport device 18.

In this transfer area 31 between the first transport device 11 and the second transport device 18, there is a difference in speed between the speed of the printing material web 12 and the speed of the belts 19 of the second transport device 12.

The signature accelerator 30 accelerates the signatures, which are completely separated from the web-shaped printing material 12 in the area of the second cutting device 21, to the speed of the belts 19 of the second transport device 18.

The signature accelerator 30 is formed from a pair of acceleration rollers 32, of which Fig.3 only one is visible. Fig.3 shows a drive motor 33 for the acceleration rollers 32.

In order to advantageously provide format variability, the first transport device 11 is set up such that, with the same number of signatures to be processed per unit of time, the speed of the belts 13 of the first transport device 11 is lower the shorter or smaller the length of the signatures to be separated from the web-shaped printing material 12 in the area of the cutting devices 15, 21.

In order to advantageously provide format variability, the signature accelerator 30 is designed such that the shorter the length of the signatures, the more it accelerates the signatures from the speed of the belts 13 of the first transport device 11 to the speed of the belts 19 of the second transport device 18.

Furthermore, in order to advantageously provide format variability, the relative position of the signature accelerator 30 to the second cutting device 21 can be adapted to suit the format.

Thus, the distance between the signature accelerator 30 and the second cutting device 21 is smaller, the shorter the length of the separated signatures. The relative distance between the signature accelerator 30 and the second cutting device 21 can be adjusted via a linear drive 34. The linear drive 34 can move the signature accelerator 30, namely the accelerator rollers 32 thereof, in the direction of the transport direction of the signatures in order to adapt the distance between the signature accelerator 30 and the second cutting device 21 in a format-variable manner in this direction.

As already stated, signatures separated from the web-shaped printing material 12 in the area of the second cutting device 21, which are accelerated to the peripheral speed of the signature collecting cylinder 26 by means of the signature accelerator 30, can be collected in the area of the signature collecting cylinder 26 to form signature stacks, wherein in the embodiment of the Fig.1 the signature collection cylinder 26 is designed as a puncture needle collection cylinder.

For example, Fig.1 the signature collection cylinder 26 has several puncture needles 35 distributed over its circumference, whereby in the area of each of these puncture needles 35 several signatures can be collected to form a signature stack. The distance between the puncture needles 35 in the circumferential direction is set to the largest format of the signatures , i.e. for the longest signatures. The distance between the puncture needles 35 in the circumferential direction corresponds at least to the section length of the longest signatures.

The circumferential speed of the signature collecting cylinder 26 relative to the speed of the printing material web 12 is greater the shorter the length of the format-variable separated signatures is.

The signature collecting cylinder 26, which is designed as a puncture needle collecting cylinder, acts in Fig.1 , 2 a cylinder 37 which presses the signatures onto the puncture needles 35 for threading. The cylinder 37 therefore provides a threading aid for the signatures on the puncture needles 35 of the signature collection cylinder 26. This cylinder 37 preferably has rails made of plastic which tension the signatures when the signatures are collected on the signature collection cylinder 26 so that the puncture needles 35 can securely needle them.

In contrast to the embodiment shown, it is also possible for the signature collecting cylinder 26 to be designed as a gripper collecting cylinder. In this case, the cylinder 37 serving as a threading aid can be dispensed with.

In Fig.1 , 2 a sensor 36 is also shown, with the aid of which the leading edge of a signature separated from the web-shaped printing material 12 can be detected. This sensor 36, in conjunction with the signature accelerator 30, can ensure that a leading edge of each signature enters the signature collecting cylinder 26 in the correct relative position to its collecting devices, in Fig.1 to its puncture needles 35, so that clean signature stacks can be formed in variable formats.

As already explained, in the embodiment shown, the folding device 10 is designed as a book folding device, in which only a longitudinal fold is formed on the separated signatures in the area of the longitudinal folding device 29. It is possible for a further longitudinal folding device to be arranged upstream of the first transport device 11 and the first cutting device 15 in order to form a longitudinal fold on the printing material that has not yet been severed. It is also possible for the signature collecting cylinder 26 to not only serve to collect signatures, but also to form cross folds on them.

As already explained above, the cutting cylinders 16, 22 of the cutting devices 15, 21 and the counter cylinders 17, 23 can be driven by drives 24, 25. This is done with the help of the drive motors 24, 25 in such a way that when the respective cut is carried out, a peripheral speed of the respective cutting cylinder 16, 22 or a peripheral speed of the cutting blades of the respective cutting cylinder 16, 22 corresponds to the speed of the web-shaped printing material in the area of the respective cutting device 15, 21. In this way, the respective cuts can be carried out particularly advantageously.

As already explained, the two cutting devices 15, 21 are synchronized in such a way that the cuts made by them in variable format are aligned transversely to the transport direction of the printing material 12, i.e. they complement each other, so that the cuts in the area of the two cutting devices 15, 21 completely separate signatures from the web-shaped printing material 12. The drive motors 24, 25 of the cutting cylinders 16, 22 and the counter cylinder are highly dynamic motors in order to accelerate and decelerate the cylinders of the cutting devices 15, 21 in accordance with the desired format of the signatures. The drive motors of the cutting cylinders and the counter cylinders of the cutting devices 15, 21 are preferably controlled via an electronic cam control which is stored in a control unit (not shown).

The adjustment of the folding device 10 to a new format takes place between two different print jobs with different formats. During a print job, the format is fixed or unchanged or constant.

Fig.4 shows a schematic side view of an offset web printing machine 40 according to the invention, which has the folding apparatus 10 according to the invention of Fig.1 The printing material web 12, from which signatures are separated in the area of the folding device 10, is held ready on a roll changer 41 and printed in at least one offset printing unit 42, 43, 44, 45.

The offset web printing machine 40 of the embodiment of the Fig.4 has four offset printing units 42, 43, 44 and 45, whereby these printing units 42 to 45 each differ in their printing format. The offset web printing machine 40 has cylinders in the area of each of the printing units 42 to 45, namely forme cylinders 46 carrying printing plates and transfer cylinders 47 carrying transfer forms, which differ in terms of their diameter and thus in terms of their offset printing format. To print a printing material web 12 during a print job, only offset printing units with the same or identical printing unit-fixed printing format are active and thus in a print-on position. Thus, in Fig.4 the offset printing unit 44 is active and in its print-on position, while the printing units 42, 43 and 45, which differ in terms of their print format from the print format of the printing unit 44, are inactive and therefore in a print-off position.

During the printing of a print job with a defined print format, at least one offset printing unit with a print format corresponding to the print format of the print job is always in its print-on position, while other offset printing units with a different print format are in their print-off position. If, after completing a print job with a defined print format, a new print job with a different print format is to be processed, at least one other offset printing unit of the Offset printing machine 40 is used for printing and is moved to its print-on position, whereas the other offset printing units with a different print format assume their print-off position.

As stated above, the folding apparatus 10 of the offset web printing machine 40 can be adapted to the print format to be printed between two print jobs, in particular by adjusting the signature accelerator 30 in its relative position to the second cutting device 21. The other format-variable features of the folding apparatus 10 have already been discussed in detail above.

The folding device 10 is designed for the largest print format in the field of offset printing units. The conversion to smaller formats takes place, as described above, by the format-variable cutting of the printing material web 12 in the area of the cutting devices 15, 21 and by the format-variable transport of the separated signatures, in particular via the signature accelerator 30.

Accordingly, if an offset web printing press 40 has offset printing units 42, 43, 44, 45 of different printing formats, the printing formats that can be printed using the offset printing units 42, 43, 44, 45 can be further processed with one and the same folding device 10, without the need for multiple folding devices.

List of reference symbols

10

Folder

11

first transport facility

12

web-shaped printing material

13

tape

14

Drive motor

15

first cutting device

16

Cutting cylinder

17

Counter cylinder

18

second transport device

19

tape

20

Drive motor

21

second cutting device

22

Cutting cylinder

23

Counter cylinder

24

Drive motor

25

Drive motor

26

Signature collection cylinder

27

Signature cylinder

28

Transport facility

29

Longitudinal folding device

30

Signature accelerator

31

Transfer area

32

Acceleration roller

33

Drive motor

34

linear actuator

35

Puncture needle

36

sensor

37

cylinder

40

Offset web printing machine

41

Roll changer

42

Offset printing unit

43

Offset printing unit

44

Offset printing unit

45

Offset printing unit

46

Form cylinder

47

Transfer cylinder

Claims (15)

1. Folding apparatus (10) of an offset web-fed printing machine,

   with a first transport device (11) in the form of a belt guide system for a web-shaped printing material,

   the first transport device (11) being set up in such a way that belts (13) thereof can be driven at a speed which corresponds to the speed of the web-shaped printing material,

   with a first cutting device (15), arranged in the region of the first transport device (11),

   the first cutting device (15) being set up in such a way that it cuts through the web-shaped printing material in a variable format in those sections which are not covered by the belts (13) of the first transport device (11),

   with a second transport device (18) arranged downstream of the first transport device (11) and designed as a belt guide system, the belts (19) of which are offset transversely to the transport direction of the printed material relative to the belts (13) of the first transport device (11),

   the second transport device (18) being set up in such a way that belts (19) thereof can be driven at a speed which is greater than the speed of the belts (13) of the first transport device (11),

   with a second cutting device (21) arranged in the region of the second transport device (18),

   the second cutting device (21) being set up in such a way that, in order to cut off signatures, it cuts through the web-shaped printing material in a variable format in those sections which are covered by the belts (13) of the first transport device (11),

   with a signature accelerator (30) in order to accelerate the signatures separated from the web-shaped printing material from the speed of the belts (13) of the first transport device (11) to the speed of the belts (19) of the second transport device (18).
2. Folding apparatus according to claim 1, characterized by a longitudinal folding device (29) for forming a longitudinal fold on the signatures.
3. Folding apparatus according to claim 1 or 2, characterized by a signature collecting cylinder (26) arranged downstream of the second transport device (18), the belts (19) of the second transport device (18) being format variable drivable at a speed which corresponds to a circumferential speed of the signature collecting cylinder.
4. Folding apparatus according to claim 3, characterized in that the signature collecting cylinder (26) is set up related to the variable format in such a way that the shorter the length of the signatures, the greater its circumferential speed.
5. Folding apparatus according to one of claims 1 to 4, characterized in that the first transport device (11) is set up in a format-variable manner in such a way that, for the same number of signatures to be processed per unit of time, the speed of the belts of the first transport device is lower the smaller or shorter the length of the signatures is.
6. Folding apparatus to one of claims 1 to 5, characterized in that the signature accelerator (30) is set up in a formatvariable manner in such a way that the shorter the length of the signatures, the more it accelerates the signatures from the speed of the tapes of the first transport device (11) to the speed of the tapes of the second transport device (18).
7. Folding apparatus according to one of claims 1 to 6, characterized in that a relative position of the signature accelerator (30) to the second cutting device (21) is variable in format.
8. Folding apparatus according to claim 7, characterized in that the shorter the length of the signatures, the smaller the distance between the signature accelerator (30) and the second cutting device (21) in the transport direction of the signatures.
9. Folding apparatus according to claim 8, characterized in that the distance of the signature accelerator (30) to the second cutting device (21) is adjustable via a linear drive (34) .
10. Folding apparatus according to one of claims 3 to 9, characterized in that the signature collecting cylinder (26) is designed as a gripper collecting cylinder.
11. Folding apparatus according to one of claims 3 to 9, characterized in that the signature collecting cylinder (26) is designed as a puncture needle collecting cylinder, and in that a cylinder (37) cooperates with the puncture needle collecting cylinder, which cylinder is set up to tension the signatures for threading onto puncture needles (35) of the puncture needle collecting cylinder (26).
12. Folding apparatus according to one of claims 1 to 11, characterized in that the first cutting device (15) and the second cutting device (21) are synchronized in such a way that their executed cuts are aligned transversely to the transport direction of the substrate.
13. Folding apparatus according to one of claims 1 to 12, characterized in that the first and the second cutting device (15, 21) have cutting cylinders and can be driven in such a way that, when the respective cut is executed, a circumferential speed of the respective cutting cylinder corresponds to the speed of the web-shaped printing material.
14. web-fed offset printing machine (40),

    with a reel splicer (41) which is set up to hold ready a web-shaped printing stock (12) to be printed,

    with at least two offset printing units (42, 43, 44, 45) which differ in terms of their printing format and which are set up to print the web-shaped substrate (12) held ready in each case with a printing unit-fixed printing form depending on a printing format of a print job,

    wherein at least one offset printing unit (43) with the print format specified for the print job assumes a print-on position for printing on the web-shaped substrate (12), while the or each other offset printing unit (42, 44, 45) with a print format deviating from the print format specified for the print job assumes a print-off position,

    with a folding apparatus (10) according to one of claims 1 to 13, which separates and folds signatures from the web-shaped substrate (12) depending on the print format of the print job.
15. Web-fed offset printing machine (40) according to claim 14, characterized in that the folding apparatus (10) is a book folding apparatus.

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