DE2732641C2 - Folding cylinder of a folder for rotary printing presses - Google Patents

Description

The invention relates to folding cylinders of a folding apparatus for rotary printing presses with several am Fastenings arranged around the circumference to accommodate folding knives, groups of grippers, rows of points, folding jaws and the same.

Letterpress and rotary offset printing machines have the disadvantage that they move in the direction of paper travel have immutable format. Once cross-folded sheets can be folded at most with an additional fold can still be halved. However, this additional fold greatly reduces the permissible speed. Same disadvantage exists when the format is divided into three by using the delta fold.

Rotogravure printing presses are generally set up for variable formats in the circumferential direction. Of the The folder must then be dimensioned for the largest format. Enlarge for smaller formats the folding difficulties, since the small formats have an impact on the peripheral speed of the for large format sized cylinders need to be accelerated. This leads to a reduction in the Machine speed. With a small format are the printing units, where it is mainly the linear ones Speed matters, only when the machine speed is increased instead of decreased will. If it is necessary in the folder to reduce the machine speed because of a 30% smaller format 80% throttle, then the rest of the machine is only used to 50%.

It was partially possible to remedy this by using larger forme cylinders with six etchings the extent. This means that there are three instead of two copies per rotation, or the corresponding number when collecting higher number of pages. The collecting cylinder of the folder must, however, be able to collect at Machines for four and six etchings per forme cylinder should be so large that ten etches and five, respectively There is space for copies in the scope. In order not to reduce the speed of the folder for small formats to have to, one often uses cassette-like ίο interchangeable folding cylinder groups. These cassettes are the used smaller and larger formats due to the use of each different better adapted to large folding cylinders, so they can individually have a lower range of variability, is Because of the different folding cylinder diameters from cassette to cassette, they will work together with the rest of the folder unchanged, but only with compromises that are not for everyone Cassettes can be cheap, allows. The same applies to the drive of the folding cylinder.

High costs would be incurred and more space would be needed if for the large format two Exemphre and the three small-format copies would each set up a complete folder. The collecting cylinder for two copies there would have to be three copies, that for three copies four of them around the circumference be able to record.

From the German patent 20 40 494 an embodiment is known, where instead of two alternatively four Folding knives can be attached.

With this solution, however, not both two and three copies can be collected, since for two Copies three or five and for three copies four or five folding knives are necessary.

Even with the embodiment known from DE-PS 16 11 292, in which a with a Folding jaw cylinder coupled folding knife cross and the gripper of a folding cylinder in their angular position are adjustable relative to one another, two as well as three specimens cannot total: < ν nelt, since here only a fixed number (three) folding knives etc. are built in.

The invention has for its object to provide a folder whose cylinder is optionally for two different numbers of folding knives, gripper groups, rows of punctures, folding jaws and the like, in short Sub-mechanisms called, can be equipped. The numbers are determined by the possibility optionally with four or six etchings on the forme cylinder circumference, two or three copies of one collect a single sentence. Suitable numbers are three or five sub-mechanisms for two Copies and four or five sub-mechanisms for three copies.

As such, a collecting cylinder that carries five folding knives can have both two and three copies collect. Since a forme cylinder divided into six etchings results in very small formats, the folding knife spacing however, it must be provided for the large-format four etchings or two copies, As described at the beginning, there are very large accelerations with six etchings. The apparently greater efficiency - the purpose of six etchings or three copies - is achieved by a necessary reduction of the machine speed because of the great acceleration nullified. Will on the other hand, in the case of three copies, four instead of three folding knives are attached, their spacing is on the collecting cylinder

smaller, which leads to a lower acceleration. The engine speed therefore only needs to be reduced insignificantly.

The object is achieved according to the invention in that the fastening devices attached to the circumference of the folding cylinder for holding folding knife, gripper or pin group cassettes, folding flap cassettes Or the like. Which are attached to themselves at regular intervals, for two different ones Compilations of sub-mechanisms are provided, which are not in an integer relationship to one another stand.

The invention is based on the example of a folder for variable formats ir.it transport of the copies through Gripper groups shown in the drawing. It shows

F i g. 1 a folder with a collecting cylinder for two large-format copies on the circumference, i.e. for four etchings on the forme cylinder circumference,

F i g. 2 the same folder with collecting cylinder of the same diameter, but with three non-single-format Copies on the circumference, i.e. for six etchings on the forme cylinder,

F i g. 3 shows a section parallel to the cylinder axes, FIG. 4 is a schematic representation of a printing press for four etchings or three copies,

F i g. 5 a schematic representation of a printing machine for six etchings, or three copies,

6 shows a folder with an inserted cylinder group configured as a cassette with three folding knives and three gripper groups on the circumference, for two copies,

7 shows a cylinder group designed as a cassette with four folding knives and four gripper groups on the circumference, for three copies, with the same folding cylinder diameters as in Fig. 6th

The paper web 1 coming from the printing units is cut into copies 4 by the cutting cylinders 2, 3. The acceleration rollers 5, 6 increase the speed of the specimens 4 to the circumferential speed of the collecting cylinder 7, resulting in the distance a. The gripper groups 8 hold the leading edges of the specimens 4 firmly and are stored in gripper cassettes 9, which in turn are distributed over the circumference of the collecting cylinder 7.

By rotating the collecting cylinder 7, the specimens 4 are brought into the area of the flap cylinder 10 brought. The folding knives 11, stored in special folding knife cassettes 12, push the specimens 4 between the folding flaps 13, which are stored in flap cassettes 14 of the flap cylinder 10. The jaws 13 transport the specimens 4 to the boom star 15 when the flap cylinder 10 is rotated.

In Fig. 1 shows the state for four etchings or two copies. Copies of the Length Li, equal to half the circumference of the forme cylinder, cut off. For this purpose the cutting cylinder contains 2 z. B. a single cutting knife 16 on its circumference, which with the bar 17 of the counter cylinder 3 comes into engagement. The drive via the intermediate gears 18, 19 and the acceleration roller 6 is such that with one revolution of the forme cylinder, the cutting cylinder 2, 3 make two cuts. At the Collecting cylinder 7 are three gripper cassettes 9 with gripper groups 8 and three folding knife cassettes 12 with Folding knives 11 attached. The fastening device b5 genes 20 and 21, which are attached for operation with six etchings, remain empty. the Gripper cassettes 9 are on the flanges 22 of the Collecting cylinder 7 attached, dl ·; Folding knife cassettes 12, on the other hand, on the disks 23. Flanges 22 and disks 23 can be rotated relative to one another, correspondingly the copy length used and by means of the screw 24 in the set position to one another held.

Three flap cassettes 14 are attached to the flap cylinder 10, while the fastening devices 25 can be used for six etchings for holding blind inserts 26 in place.

Instead of changing the folding knives and gripper groups combined in cassettes, the entire cylinder group according to FIG. 6 can be set up in a known manner for replacement. As a replacement cartridge then according to the invention there is one according to FIG. 7 with a different number of folding jaws 13, folding knives 11 and Gripper groups 8, but with the same cylinder diameters to disposal. It is easy to see that there are no problems with the paper guide rollers 30, the boom star 15 and the longitudinal fold 31, since the cylinder diameter for both Cartridges are the same.

The gripper groups 8 and the folding knives 11 are through the cam set 32, the folding jaws 13 through the Curve 33 controlled in a known manner. The flap cylinder 10 and the collecting cylinder 7 are driven by the wheels 34 and 35 connected and rotate in bearings 36, 37, 38, 39, which in turn are housed in the folding walls 40, 41. Instead of the gripper cassettes 9, cassettes with groups of punctures can also be used.

Mode of action

In Fig. 4, the forme cylinder 42 has four etchings, i. H. two copies per cylinder revolution produced. This includes a cutting knife 16 in the folder 43 on the circumference of the cutting cylinder 2. The cutting cylinders 2, 3 rotate twice per forme cylinder revolution. There are three on the collecting cylinder 7 Folding knife cassettes 12 and three gripper cassettes 9 attached. This allows you to choose between two copies are passed on to the flap cylinder 10 per forme cylinder revolution, or both copies can be collected on the collecting cylinder 7 and passed on to the flap cylinder 10 as the only copy will. Two thirds of the laminate cylinder 7 are occupied per form cylinder revolution. Corresponding is their gear ratio.

In Fig. 5 the forme cylinder 42 has six etchings, i. H. three copies per cylinder revolution produced. These include two cutting knives 16 in the folder 43 on the circumference of the cutting cylinder 2. The cutting cylinders 2, 3 rotate one and a half times per revolution of the forme cylinder. Your peripheral speed is thus adapted to the shorter specimen length compared to four etchings. On the collecting cylinder 7 four folding knife cassettes 12 and four gripper cassettes 9 are now attached. With this you can optionally three copies per forme cylinder revolution are passed on to the flap cylinder 10, or the three copies can be collected on the collecting cylinder 7 and together as a single copy to the Flap cylinder 10 are passed on. The transmission ratio forme cylinder / collecting cylinder is changed with the gear 44. Three quarters of the collecting cylinder circumference are used per form cylinder revolution proven.

The alternatives with four or six etchings or two or three copies are thus in one and

allows the same folder. Only through education 3 ^ 3 _ 9 exchange of folding blade, rapier and Klappenkasset- ι ~ 4 \ th and must be increased by changing two ratios, or by exchanging the cylinder-group-KAS, as opposed to acquaintances where cassettes this is achieved according to the invention. At the same time> the ratio of the increase in speed, the folding cylinders remain in reasonable dimensions. Another main advantage is that with six etchings 3_ _ J_ _ 3 or with three copies, i.e. always with a small 2 T ~ 2 ^ format, the speed of the folder only has to be in the ratio: n.

In addition 5 sheets of drawings

Claims (5)

Patent claims: 1. Folding cylinder of a folder for rotary printing presses with several attachments arranged on the circumference to accommodate folding knives, gripper groups, rows of punctures, folding jaws, which are attached to themselves at regular intervals, characterized in that the Fasteners (20, 21, 28, 29) for two different combinations of folding knives - (12) gripper- or puncture group cassettes (9), folding flap cassettes (14) are provided, which in none integer relationship to each other. 2. Folding cylinder according to claim 1, characterized in that its diameter remains essentially unchanged regardless of the number of fastenings attached (20, 21, 28, 29). 3. Folding cylinder according to one of claims 1 or 2, characterized in that the two different There are compilations of both three and four groups of fortifications (20,21,28,29). 4. folding cylinder according to one of claims 1 or 2, characterized in that the two different There are compilations of both three and five groups of fortifications (20,21,28,29). 5. folding cylinder according to one of claims 1 or 2, characterized in that the two different There are compilations of both four and five groups of fortifications (20,21,28,29).