JPH05309815A - Rotary press - Google Patents

Abstract

PURPOSE: To obtain a rotary press with an impression cylinder which can easily adjust the impression force. CONSTITUTION: In a proof press, while the joint work of the same impression cylinder 2 of a constant width with a plate cylinder 1 of a different operating width applies an impression force on a printed web 3 and the plate cylinder 1 only for the operating width, the ends 2(apply a reduced impression force which is possible by being drawn back by retreating forces R from the plate cylinder 1. Protective sleeves 9 which are endless, loosely rotating together, have an inner diameter several cm larger than the outer diameter of the impression cylinder 2, and is adjustable in the axial direction are provided in wedge- form gaps between the ends of the plate cylinder 1 and the impression cylinder 2, directly continuing to the printed web 3 between the plate cylinder 1 and the impression cylinder 2.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention comprises a plate cylinder for different printing widths and an impression cylinder cooperating with the plate cylinder for the printing of printing webs of different widths. The invention relates to a rotary printing machine adapted to exert individually adjustable pressing forces on different width printing webs.

[0002]

2. Description of the Related Art A rotary printing press of this kind is known from EP-A-4.
No. 39 822, this rotary printing press also allows printing webs of different widths to be printed qualitatively reliably by means of its own impression cylinder. For this purpose, the impression cylinder has a large number of at least partially individually adjustable supporting elements which are arranged axially side by side and which support elements are arranged on the impression cylinder upholstery. In addition, different pressing forces can be applied according to the print width. In the end region of the impression cylinder, a support element is additionally provided which acts in the direction opposite to the pressing direction in order to pull the impression cylinder away from the plate cylinder at the end.

In a so-called proofing machine in which a new plate is inspected and a proof is taken out, the same proofing machine is used.
One after another, it is required to be able to mount various plates having different printing widths. For this reason, it is common to proof print plate cylinders for continuous printing machines having different working widths on the same proofing machine.
In addition to the variable plate cylinder bearing, a printing ink pan with adjustable width is provided.

Similarly, in impression cylinder systems, corresponding measures must be taken to switch to other working widths. If, within the scope of the cylinder body, a wider and more impressionless impression cylinder is used than the plate cylinder, essentially two problems arise. -The doctor system does not clean the plate cylinder cleanly in the edge region; this results in the transfer of printing ink to the impression cylinder: -the corners of the plate cylinder are Tendency to local overloading of the tension; this results in contact scars in the torso: and so on.

Therefore, as is usual, in a certain way, a large number of impression cylinders with correspondingly tuned working widths are loaded into the swivel system. The associated impression cylinder, which has a corresponding pressing width, is then swung into the working position by the swiveling system for proofing a plate with a defined working width. However, this requires a relatively complex construction and, according to the working width to be expected, requires the storage of a large number of impression cylinders. Furthermore, the conversion to another working width is very time consuming.

The rotary printing press known from EP-A-439 822 also uses plate cylinders of different working widths without problems in spite of the individually adjustable pressing forces over the width. Used for proofs. In the impression cylinder, in order to avoid the formation of printing ink at the edges of the plate, the upholstery is separated from the plate cylinder in this area by the supporting elements acting in opposite directions, thereby printing the plate cylinder. A small gap must be created between the area contaminated with ink and the upholstery of the impression cylinder. It is therefore possible to separate the ends of the cylinder upholstery, however, in the course of time, on the impression cylinder, an area of printing ink forms via the contact point of the printing ink.
Finally, until the gap between the impression cylinder and the plate cylinder is filled,
Can be formed. The transfer of the printing ink is not a direct impediment by itself, however, over time, it swells in the edge region of the upholstery of the impression cylinder, causing a local increase in diameter, which Sufficient to negatively affect edge / center color fusion. Moreover, the upholstery of the impression cylinder is impaired and damaged by the printing ink-melting material.

[0007] In general, the separation from the plate cylinder is improved by increasing the retreat pressure of the impression cylinder tension, however,
Then, in the edge area, the pressing force is reduced so that the proof in this area is insufficient.
On the other hand, if the receding pressure is reduced to the extent that the proof is sufficient, printing ink can also be transferred in this case.

Similar problems generally occur with decorative prints that are proofed with the maximum plate cylinder width. In that case, the plate cylinder is engraved over the entire width, however, in that case, usually, only a partial upholstery is effected by the material to be printed. The change of the material width can then be carried out in steps of a few mm, which means a very delicate staging of the proofing system and usually a correspondingly large number of different impression cylinders. I need. Here again, without staging of the impression cylinder, the contents of the printing ink in the small depressions lying on the outside of the web material are transferred onto the impression cylinder. In this case, too, a simple bending of the impression cylinder in the region outside the web material only results in an improvement for a short time at most.

[0009] Research has already been carried out on the use of adhesive bands to cover the area of the impression cylinder at the risk of contamination. However, the production of adhesive bands is relatively complicated and is by no means suitable for continuous operation. The removal and replacement of the adhesive band is, in addition, cumbersome and, in fact, can only be difficultly realized.

[0010]

SUMMARY OF THE INVENTION The present invention eliminates the above-mentioned drawbacks of the prior art, in particular a rotary printing press of the type mentioned at the beginning with different plate widths, with the same impression cylinder. It is intended to be formed so that it can be used on the plate cylinder without impairing the print quality.

[0011]

According to the present invention, in order to solve this problem, the pressing force on the impression cylinder is set above the width of the impression cylinder.
Controlled so that there is a reduction of the pressing force between the impression cylinder and the plate cylinder, i.e. on both sides of the outside of the printing web, and the reduced pressing force between the impression cylinder and the plate cylinder A rotary printing press, in the region of pressure, provided with one axially guided, ring-shaped protective sleeve, which encloses the impression cylinder at small intervals and rotates loosely with the impression cylinder. It is characterized by.

The reduction in force prevents the ingress of printing ink into the area of the end of the ring-shaped protective sleeve.

The ring-shaped protective sleeve is formed as a thinner, highly flexible metal ring, one corner of which is sandwiched between the impression cylinder and the plate cylinder and the other. Advantageously, the corner is connected to a guide bearing, so that the surface of the impression cylinder is protected and covered against jetting of printing ink. The mounting of the guide bearings is designed in such a way that the device can be pushed manually or automatically or at the respective charging point.

In addition, it is advantageous to provide a device, for example a doctor knife, for removing the residue of the applied printing ink from the link-shaped protective sleeve in the direction of rotation of the ring-shaped protective sleeve. .. This is because otherwise undesired continuous formation of dried printing ink can occur.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail with reference to the accompanying drawings showing the embodiments thereof. In the proof machine shown in FIG. 1, a plate cylinder 1 having a plate on its upper surface is replaced by an impression cylinder 2
Together with act on the print web 3 to be printed. The plate cylinder 1 is fitted with another plate cylinder 1'having another print width and the bearings 4 or 4'of the plate cylinder 1 or 1 ',
It can be selectively replaced.

On the other hand, in the illustrated calibrator, in the case of various different working widths and plate cylinder widths, in contrast to the known proof machines having interchangeable impression cylinders, there is always a constant value. It is operated by the impression cylinder 2 having the same width. In order to adapt to different working widths, the impression cylinder 2 is formed as follows, that is to say that this impression cylinder 2 is able to exert an individually adjustable pressing force on its width. Has been done. In particular, in the region of the working width of the printing web 3 or of the plate cylinder 1, a pressing force P in the printing direction acts on the plate cylinder 1, while at the free end 2 ′ of the impression cylinder 2 it recedes. The force R acts against the printing direction, but this receding force R pulls the end 2 ′ of the impression cylinder 2 from the printing surface and the plate cylinder 1.

In addition, the impression cylinder 2 is, for example, as described in EP-A 139 822, in order to achieve the possibility of individual adaptation of the pressing force over the width and the generation of the receding force at the ends. A non-rotatable carrier 5 and a body covering 6 rotatable around it can be formed on this.
Are supported against the carrier 5 by a pressing force that can be adjusted individually or in groups by a series of supporting elements 7 arranged axially side by side. In that case, in the end region, in order to apply the backward force R, additionally,
Supporting elements are provided on the opposite side of the upholstery 6.

The support elements 7 are formed as hydrostatically following elements, which support elements 7 advantageously allow a wide range of friction-free bearings of the upholstery 6 independent of the pressing force. is there. However, instead of a series of support elements 7, the impression cylinder 2 is also conventionally formed, for example, as a so-called bending impression cylinder, in which case in the operating position a pressing force can be generated. However, it can also be formed in the edge region such that an oppositely directed retracting force can be generated.

As can be seen from FIG. 2, the plate cylinder 1
Has a small chamfer or chamfer 8 at its outer corner. In each case, the impression cylinder 2 comprises a printing web 3
Alternatively, it is lightly retracted in a region 2 ′ outside the working width of the plate cylinder 1, so that the linear force in this region is clearly reduced. Edge 8 of plate cylinder 1
A small wedge-shaped clearance K is formed between the plate cylinder 1 and the cylinder tensioner 6 of the impression cylinder 2, and the plate cylinder 1 and the impression cylinder 2 are mutually disposed in the end region through the clearance K. It is advantageous to be separated.

The upholstery 6 of the impression cylinder 2 is usually made of a highly elastic material having sufficient flexibility in order to achieve good print quality, in which case in addition other requirements For example, as long as it is to be processed by electrostatic pressing means, the requirements regarding the electrical resistance value should be met. However, commonly used materials are sensitive to printing ink imprints that may reach from the plate cylinder 1 onto the ends of the upholstery 6. Conventional impression cylinder materials are attacked and partially swelled by the printing ink or the solvent contained therein, such as toluol, which can be a problem in fast depletion and in the supply of printing webs. is there.

The impression cylinders 2 do not have to be replaced and adapted together either when changing the plate or when changing its width, and work further with the same impression cylinder. In the end region of the plate cylinder 1, one ring-shaped protective sleeve 9 is provided on each side of the plate cylinder 1. The surface is coated in the edge areas to protect the transfer of printing ink. This ring-shaped protective sleeve 9 is, for example, an endless ring-shaped protective sleeve 9 having a wall thickness of about 0.1 mm and a number c.
It consists of a spring steel band having a width of m.
In particular, the spring steel band must be used without abutting points. For example, a thin-walled nickel ring produced by "electroforming" must be used. Templated synthetic resin rings are also contemplated. The diameter of the ring-shaped protective sleeve 9 is larger than the outer diameter of the impression cylinder 2.
Slightly larger. The diameter difference is ring-shaped protective sleeve 9
Is advantageously chosen such that it can loosely rotate with the impression cylinder 2. Normally, in the case of an ordinary impression cylinder diameter in the range of 25 cm, the maximum outside diameter of the cylinder is 0.
The inner diameter of the ring-shaped protective sleeve 9 is larger than 5-5 cm, preferably 3-4 cm.

The ring-shaped protective sleeve 9 is provided between the upholstery 6 of the impression cylinder 2 and the outer corner of the plate cylinder 1 from the outer corner of the printing web 3, for example, the corner of the paper. ,
Placed to have a distance of about 5 mm or slightly less. For the positioning of the ring-shaped protective sleeve 9, its outer angle is fixed on a guide ring 10 which is rotatable by bearings 11 around a non-rotatable outer ring 12. Therefore, during operation of the calibrator, the ring-shaped protective sleeve 9 is accompanied by the guide ring 10 with the impression cylinder 2 and rotates together with the impression cylinder 2; however, it corresponds to different diameters. And rotate at a slightly different speed. The bearing 11 is protected from jetting of printing ink during operation by the internal angle 10 ′ provided on the protection ring 10.

The non-rotatable ring 12 is fixed to the frame 13 of the calibrator so as to be adjustable in the axial direction and movable in the radial direction. This anchorage is preferably formed vertically movable by means of a kind of spring member, which allows the outer ring 12 to follow the stroke movement of the impression cylinder 2 and, by means of the spring, always towards the impression cylinder. To be pulled. Therefore, the adaptation of the ring-shaped protective sleeve 9 to a modified working width or a modified plate cylinder diameter is possible in a simple manner. Therefore, the impression cylinder 2 is provided with a simple adaptation of the position of the protective sleeve 9 without any risk of obstruction or damage of the end 2'overlying the impression cylinder 2 and any plate cylinder 1 and working width 3 To be adapted without problems.

In order to remove the rest of the printing ink reaching the ring-shaped protective sleeve 9, on both sides, for example,
In order to scrape off the printing ink which has reached the ring-shaped protective sleeve 9 respectively, a doctor knife 1
It is advantageous to provide 4. This doctor knife 14
Can be attached to the non-rotatable ring 12 behind the print gap in the direction of rotation

In the case of decorative printing, the solution according to the invention is also used to advantage. Figure 3 for decorative printing
As can be seen from the figure, it is operated with the maximum plate cylinder width, in which case the plate cylinder 1 has a decorative pattern over the entire width, for example engraved. However, in most cases, the paper 3 is simply provided on the partial upholstery on the working width B which is present in each case. Instead of working with an impression cylinder tuned to this working width B, the impression cylinder 2 with the largest width is used. In this case as well, the impression cylinder 2 has a printing pressure P formed in the working width B, while the end 2 ′ of the impression cylinder is separated from the plate cylinder 1 by a corresponding reaction force R. Also in this case, the corners of the paper web 3 are also provided on each side with one ring-shaped protective sleeve 9, the diameter of which is slightly larger than the outer diameter of the impression cylinder 2. This ring-shaped protective sleeve 9 rotates loosely together with the impression cylinder 2. In this case, the ring-shaped protective sleeve 9 is clamped in its entire width in the gap between the plate cylinder 1 and the impression cylinder 2, so that a guide for another ring-shaped protective sleeve 9 must be selected. Instead, for example, a ring-shaped protective sleeve can be guided laterally via a guide member,
In this case, the guide member is skived in the lower region, which allows the unit to move over the waist width without problems. This guide member, for example,
It can be made of a suitable synthetic resin, for example Teflon PA6, or the like, and this guide member can at the same time also serve as a holder for the doctor knife.

The guide member has a ring-shaped protective sleeve,
It is also conceivable to provide guidance only partially, for example at three locations. This guide point can also be formed as a roller.

[0027]

Since the present invention has the above-mentioned structure and operation, it eliminates the drawbacks of the prior art described above, and in particular, a rotary printing machine of the type described at
It is intended to provide a proofing machine configured so that different plate widths can be used on the plate cylinder by the same impression cylinder without impairing print quality.

[Brief description of drawings]

FIG. 1 is a side view of a calibrator according to the present invention.

FIG. 2 is a detailed cross-sectional view of the calibrator of FIG.

FIG. 3 is a side view of a decorative printing machine according to the present invention.

[Explanation of symbols]

 1 plate cylinder 2 impression cylinder 3 printing web 4 bearing 5 carrier 6 cylinder tension 7 supporting element 8 chamfer 9 ring protective sleeve 10 guide ring 11 bearing 12 non-rotatable ring 13 frame

Claims (10)

[Claims] 1. A plate cylinder (1) for different printing widths,
An impression cylinder (2) having a plate cylinder (1) and an associated impression cylinder (2) for the printing of printing webs (3) of different widths
On the impression cylinder (2) in a rotary printing press which is adapted to exert individually adjustable pressing forces (P) on different printing webs (3) over its width. The pressing force (P) is exerted on the width of the impression cylinder (2) between the impression cylinder (2) and the plate cylinder (1) as follows, i.e. on both sides outside the printing web (3). Is controlled such that a reduction of the pressing force occurs, and the impression cylinder (2) is surrounded by a small distance within the area of the reduced pressing force between the impression cylinder (2) and the plate cylinder (1). A rotary printing press, characterized in that each is provided with one axially guided ring-shaped protective sleeve (9) which rotates loosely together with the impression cylinder (2). 2. The rotary printing press as claimed in claim 1, wherein the ring-shaped protective sleeve (9), which rotates together loosely, has a diameter which is slightly larger than the outer diameter of the impression cylinder (2). 3. The inner diameter of the ring-shaped protective sleeve (9) which rotates loosely together is 0.5 than the outer diameter of the impression cylinder (2).
A rotary printing press according to claim 2, wherein the rotary printing press is larger than -5 cm, preferably larger than 3-4 cm. 4. A ring-shaped protective sleeve (9) which rotates loosely together is journaled in a frame (13) of a rotary printing press by guide bearings (10, 11, 12). Or 3 rotary press. 5. The guide bearing (10, 11, 12) of the ring-shaped protective sleeve (9) rotating together is adjustable in the axial direction of the impression cylinder (2).
Rotary printing machine. 6. The rotary printing press according to claim 5, wherein the guide bearings (10, 11, 12) are movable in the pressing direction and the radial direction, preferably by a kind of elastic member. 7. The internal angle of the ring-shaped protective sleeve (9) between the plate cylinder (1) and the impression cylinder (2) is as follows: from the external angle of the printing web (3), The rotary printing press according to any one of claims 1 to 6, wherein the rotary printing presses are arranged so as to have a small gap of at most several mm. 8. Carrier (5) in which the impression cylinder (2) is stationary
And a upholstery (6) rotatable around the carrier (5), the upholstery (6) being provided by a set of supporting elements (7) arranged axially side by side. Supported on the carrier (5), the support element (7) can exert an adjustable pressing force (P) in the printing direction in the area of the printing web (3), while At the end of the printing web (3) there is provided a retracting element (7 '), which retracting element (7') is capable of exerting a retracting force (R) opposite to the printing direction. The rotary printing press according to any one of claims 1 to 7, wherein: 9. The plate cylinder (1) has an inclined surface or a chamfer (at a chamfer) at its outer corner so that a clearance (K) is formed between the end of the plate cylinder (1) and the impression cylinder (2). Claim 1 which has 8)
[8] The rotary printing press according to any one of [8] to [8]. 10. The rotary printing press as claimed in claim 1, wherein a doctor knife (14) is provided for scraping off the remainder of the printing ink from the ring-shaped protective sleeve (9).