Folding machine: overview, types, characteristics, operating principle
Folding machine is an apparatus used at almost all printing enterprises. This machine allows to fully mechanize such a process as folding.
At the present time, there are twodifferent types of folding machines. The first type is knife devices, and the second type is the cassette ones. However, there is also a third type of units, but nothing fundamentally new, it is just a combination of the two previous types of machines.
The most important difference between these two types is that,that the formation of the fold occurs according to fundamentally different schemes. The knife folding machine forms a fold of the sheet by means of two rollers rotating towards each other, as well as a blunt knife. The principle of operation of this device is quite simple. A blunt knife hits the sheet in the right place, thereby forming the place of the future fold. Also, this operation simplifies further grabbing of the sheet by rollers. After the seam passes through the rollers, the folding place is heavily compacted.
Cassette and combination machines
If we talk about folding machines cassettetype, the formation of the fold is carried out by means of two rollers and a cassette instead of a blunt knife. The principle of operation of this unit is also very simple. Feed rollers bring the sheet to the end of the cassette. Immediately after the sheet reaches this point, it stops moving forward. However, the rollers still push the sheet of paper. As a result of this operation, a deflection of the sheet is formed in the place where the fold will be located. The process of ironing and sealing the seam in this type of machine is carried out in the same way as in the knife.
Combined folding machines work in such a way that one of their sections is a copy of the knife machine, and the second section is a copy of the cassette unit.
It is worth noting that there is another typeFolding machines are rotational. However, the principle of their work differs significantly from the previous two. The greatest difference is the quality of folding. Notebooks produced by such an aggregate are usually characterized by inferior quality. Such a disadvantage is explained by the fact that rotational folding machines operate at too high speeds, which does not allow coincidence of the bands in the notebook on adjacent pages.
However, it is necessary to understand that both cassette andKnife aggregates also have their disadvantages and advantages. The advantages of knife types of machines can be attributed to the fact that they always provide high accuracy of finished products, which allows you to comply with all the technical requirements that are required for folded products. In addition, the accuracy of the operation does not depend on the density of the paper.
The advantage of the cassette machine is,that the location of the folds in the notebook will also have high accuracy. This indicator also guarantees high accuracy and minimum deviations that can be tolerated. However, everything relates only to the process in which certain types of paper will be used.
Stamps of units
Separation of all units by their brandsis carried out on large format and small format. Large-scale units can include such brands as knife single-stage machines F-1 or BFA-2. To small-format aggregates it is possible to carry such mark, as the cassette machine FK-30. It is also worth noting that each of these machines is designed for a particular type of work. FK-30, for example, is intended only for folding sheets for fly-covers or covers. But large-sized F-1 and BFA-2 can perform up to four folds.
There are also some brandscombined machines, for example, FKN-60. This unit is designed for perpendicular folding with four folds. Since this type of machine is combined, the first perpendicular fold is performed according to the principle of the knife machine, but the following three folds are performed on the principle of a cassette machine.
Folding machine arrangement
There are many different configurationsfolding machines, which may also differ in size, performance, etc. However, there are structural details that are present in absolutely all units. These parts include the feeder, folding sections, receiving modules.
Currently, the best folding machines use only two types of feeder - a planar, round-stemmed.
The first type of feeder feeds the sheetsfrom a flat pile that is installed on a plane. To feed sheets into the machine of this type, there is a system, which includes three mandatory elements: a stack table, a sheet separation system, a sheet feeding system.
It can also be noted that there is a varietysuch feeders, which is called pallet. The pallet feeder allows loading a stack of paper into the unit on a small pallet, which is placed in the receiving unit of the unit.
One of the companies that deals withproduction of these machines, is HP Indigo Digital Press. They produce professional equipment for folding operations with the name GUK Falzmaschinen. Folding machines Guk are characterized by certain parameters:
- The first thing that can be identified is an easy dockingsuch parts as a feeder, a fold, additional devices. In addition, these parts are easily interconnected, they are also easily synchronized with the control system.
- There is an automatic setting for the sheet format. This feature is present in most feeders.
- The performance of these devices is very high - about 40,000 operating cycles are carried out within an hour.
- The production and processing of folding rollers are carried out by a special technology, which uses high-strength steel, as well as rings of polyurethane.
- Implementation of the perforation process in the cassette station, as well as before the second and third knife.
- The management of knives in these machines is completely electronic.
Currently, the company operates withThe name BOBST, which is engaged in the production of this type of machine since the distant 1942. The first unit of this company is PCR 382. Beginning with this machine and up to the present day the company has a large research and development staff, and also carries out development work. All these units are aimed at improving existing folding gluing machines.
It should be noted that the folding process isone of the necessary and most important processes in printing, which is attributed to post-print processing. However, if mechanized units are used now, manual folding machines were used before. But it is worthwhile to understand that the productivity of a person is several times lower than that of a machine. In addition, a person is not able to carry out the required number of operations for a certain period. Therefore, manual versions of these machines are used only for specific purposes and a very limited edition of any publication.
The development of technology has led to the fact thatFolding machines have acquired additional features. There was an opportunity of gluing with usual glue, glue for temporary fixation, punching, scoring, etc. However, it is worthwhile to understand that the more a device can, the more expensive it will cost. The price of the folding machine starts from about 4,000 rubles and can reach 2-3 million. The cost of the unit depends on the set of functionality and performance.