HK1005890B - Apparatus for applying an embossing sheet replica to a flexible web - Google Patents

Description

The invention relates to a device for applying an impression of an stamping film onto a flexible material track with a stamping roller and at least one printing roller, by means of which the stamping film and the material track are pressurised against each other and against the surface of the stamping roller.

The first is the use of a device known as a "de-c- 32 10 551" which has a number of rolls, each paired together on a rolling stock. The rolls can be set individually, with one or two adjacent inner rolls first and then the other rolls being brought outwards to be attached to the stamping roller.

Banknote paper, with this familiar device, it cannot be ruled out that the full surface of the printing roll and the stamping roller will cause an undesirable compression of the fibres of the flexible material track and thus an undesirable change in the characteristics of the flexible material track.

Therefore, DE-C-40 24 537 proposes a device for the application of an impression film onto a flexible material track which, even on sensitive flexible material tracks to be printed with an impression film, avoids undesirable compression of the fibres of the flexible material track and thus an undesirable change in the characteristics of the flexible material track without affecting the speed of operation of the device.

However, due to thickness tolerances of the material path and/or thermal defects in the form, i.e. thermal imperfections of the stamping roller, these known devices may result in uneven depths of impact of at least one roll into the material path and consequently an uneven stamping film impression.

The purpose of the invention is to develop a device of the type described above in such a way that the different depths of impact of at least one roll on the flexible material track, i.e. uneven foil impressions on the flexible material track, are reliably avoided by simple means.

This problem is solved in the case of a device of the type described in the foregoing by the fact that each printing roll has an inner socket and an outer socket concentric to the inner socket, with a gap between the inner and outer sockets, that the inner sockets have at least one circular exception on their outer surface facing the outer socket to accommodate an associated ring-shaped compensating element consisting of rubber elastic material and pressing against the inner and outer sockets, that the outer sockets have an inner socket and an outer socket concentric to the inner sockets, with inner sockets and outer sockets being made of different materials and are firmly connected to each other.This defined mechanical tension makes the inner and outer bearings of the corresponding stamping roll precisely centred on each other. In the case of radial loading of the corresponding stamping roll due to a thickness tolerance of the material path to be stamped and/or due to thermal imperfection of the stamping roller, the outer bearings can be balanced with the help of the corresponding elastically flexible compensating element relative to the inner bearings of the corresponding stamping roller and thus equal the thickness tolerances of the material path or the shape defects of the stamping roller.A device which is easy to manufacture and which has the advantage of simple, time-saving and precise arrangement of at least one elastically flexible ring-shaped balancing element in the gap between the inner and outer sockets of the corresponding roll, is obtained if the inner socket has at least one circular aperture on its outer surface facing the outer socket to accommodate an associated ring-shaped balancing element. It is also possible to select the appropriate dimensioning of at least one circular aperture in the outer socket of the inner socket and a suitable material profile of the corresponding dimension of the balancing element by means of appropriate dimensioning of the corresponding socket.The material of at least one elastically flexible ring balancing element has a hardness of between 50 and 100 Shore, preferably between 60 and 90 Shore. Elastomer materials are available which have such hardness. Optimal matching of the material and/or mechanical properties of the flexible material to be stamped is achieved when the outer shell is joined by an inner shell and a concentric shell, consisting of different internal and external materials.The inner shell can be made of a suitable metal or a suitable metal alloy. The outer shell can be made of a cotton-filled phenolic resin pressed mass. Of course, other material combinations are also possible, depending on the purpose of use.

In the case of a device of the type described at the outset, in which the roll is fitted with an adjusting device to adjust the distance of the roll relative to the roll and thus to adjust the pressure applied to the roll and the material track, it has proved to be advantageous to place the inner bearings by means of bearings on an eccentric section of a bearing axis rotatable centrally on a bearing axis. A scaled adjustment device may be connected to the axis to adjust the eccentricity of the bearing axis and to determine the position of the load bearing axis in the position set. This means that the bearing axes can be adjusted in an appropriate direction, which is particularly advantageous when the bearing axis is arranged in a linear direction and is 500 mm wide.

A ring-shaped covering element may be provided on each side of at least one roll to seal the gap between the inner and outer sockets. In such a design of the device of the invention it has been found to be useful to attach the covering elements to the inner socket of the corresponding roll, with the outer shell of the outer socket radially overlapping each of the two side covering elements. In order to eliminate without difficulty the dimension tolerances of the inner and outer sockets in the axial direction, it has been shown to be advantageous in such a design of the latter types of sockets to have the inner socket wider axially than the outer socket.In order to seal this gap between the corresponding cover element and the outer cover to the gap between the inner cover and the outer cover, it has proved to be advantageous to have the cover elements formed on their inner side by a circular groove surrounding them, in which a ring-shaped element is arranged behind the corresponding cover element and facing the outer cover. The latter transparent opening is achieved not only since the two guiding elements are oriented axially relative to the outer cover,It also prevents dust or other particles from entering the gap between the inner and outer sockets.

If, after a long service life or service life, such a roll requires repair, e.g. replacement of at least one elastically flexible compensating element between the inner and outer sockets, it is possible to disassemble the corresponding roll into its individual parts and, if necessary, repair it in a time-saving manner.

Whereas the known devices of the type according to the invention, e.g. hydraulically pressure controlled delivery of the coils to the stamping roller, can only compensate for relatively large thickness tolerances in the material path to be stamped and/or relatively large thermal irregularities of the stamping roller, the device according to the invention can compensate well for relatively small errors at high working speeds of the devices.

Further details, characteristics and advantages are given in the following description of an example of the device of the invention for applying a film print to a flexible material track, shown in the following paragraph: 1a partial view of the device in the direction from the undrawn moulding roller to a pair of rolls, where the supporting console on which the moulding roller is linearly adjustable is only sectionally drawn,Fig. 2a section along the line II-II in Fig.1 through the device, where the moulding roller is only sectionally indicated,Fig. 3a view of the section of the device as shown in Fig.1 in the direction of the arrow III, i.e. from the side, where the corresponding moulding roller and the bearing box are half-cut, andFig. 4an enlarged representation of a section of moulding roller and a section of bearing box in a magnified representation.

Figure 1 shows a device 10 for applying a stamping film print on a flexible material track, but does not show the heated stamping roller in order to illustrate a pair of stamping rolls 12 which are mounted on a bearing 14 which rotates parallel to each other. Each stamping roll 12 can be adjusted as desired by means of an adjustment device 16 in relation to the undrawn stamping roll of the device 10. The bearing 14 is arranged along a linearly adjustable bearing console 18 which is drawn in a section.

Figure 2 shows the cross-sectional profile of the load-bearing console 18, on which the bearing bearing 14 is arranged linearly for the two stamping rolls 12. The reference 16 also refers to the scaled adjustment devices for the stamping rolls 12. With the help of the adjustment devices 16, the stamping rolls 12 can be adjusted as desired in relation to the heatable stamping roller 20 shown in Figure 2. By adjusting the pressure coil 12 relative to the stamping roller 20 as desired, a defined adjustment of the distance of the corresponding stamping coil 12 relative to the stamping rolls 20 and thus a defined adjustment of the pressure coil 20 and the printing coil 12 between the stamping roller 20 and the stamping material being passed through (not passing through) is possible.

Fig. 3 shows in a side view the bearing console 18 in sections on which the bearing block 14 is arranged linearly for a pair of rolls of rolls 12 and adjustable. By means of a screw element 22 (see also Fig. 2) it is possible to fix the bearing block 14 in a certain position on the bearing console 18. From Fig. 3 and especially from Fig. 4 it is shown that on bearing block 14 between two bearing legs 24 spaced apart, a bearing axis 26 is laid, which has an eccentricity 30 between two coaxial bearing sections 28. The eccentricity 30 has an eccentricity 28 in relation to the bearing sections on both sides.

Each roll 12 has an inner nozzle 32 which is rotatably placed on the eccentric section 30 of the bearing axis 26 by means of bearings 34 such as ball bearings. The bearings 34 are kept at a defined distance from each other by means of a spacing ring 36. The inner nozzle 32 is formed on its outer surface 38 by spaced circular exceptions 40 designed to accommodate an associated ring-shaped compensating element 42 from a material of elastically defined hardness.

The inner socket 32 is concentrically surrounded by an outer socket 44 which has an inner socket 46 and an outer socket 48. The inner socket 46 is e.g. made of a metal or an alloy, while the outer socket 48 is e.g. made of a phenolic resin press etc. The inner and outer sockets 46 and 48 are glued and/or bonded together.

The inner diameter of the outer socket 44 or the inner shell 46 of the outer socket 44 is slightly larger than the outer diameter of the inner socket 32 so that a gap 52 is formed between the outer shell surface 38 of the inner socket 32 and the inner shell surface 50 of the outer socket 44. This gap 52 is bridged by the elastically pliable ring balancing elements 42 which press against both the inner and outer sockets 32.

In order to prevent edge printing on sensitive material such as banknote paper, the outer cover 54 of outer socket 44 or the outer shell 48 of outer socket 44 is slanted at a small angle at its two edge sections 56.

Each cover 58 is fitted on its inner side 62 with a circular groove 64 in which a ring seal element 66 is placed. Each seal 66 is not only attached to the corresponding ring seal element 58, but also to the outer seal 44 of the corresponding cover roll 12, so that the corresponding access element 66 to the cover space between 52 inlet and outlet is sealed by means of the corresponding right element 66 of the cover space between 32 inlet and outlet. Furthermore, the two seals 66 and 44 allow a limited axial reflectivity relative to the corresponding outer seal element 32 of the cover roll.

It is also clearly visible from Figure 4 that the inner box 32 is axially wider than the outer box 44 or the inner and outer shells 46, 48 of the outer box 44 respectively, so that there is a play or gap room 68 between each cover element 58 and the corresponding outer box 44.

Claims (7)

1. An apparatus for applying an embossing sheet imprint onto a flexible material web, with an embossing roller (20) and with at least one pressing-on roller (12), by means of which the embossing sheet and the material web can be pressed against each other and against the lateral surface of the embossing roller (20), characterized in that the/each pressing-on roller (12) has an inner bush (32) and an outer bush (44) concentric with the inner bush (32), in which arrangement a gap (52) is provided between the inner and the outer bush (32, 44), that on its outer lateral surface (38) facing the outer bush (44), the inner bush (32) has at least one peripheral recess (40) for receiving an associated annular compensation element (42) which consists of a rubber-resilient material and which presses against the inner and the outer bush (32, 44), and that the outer bush (44) has an inner sleeve (46) and an outer sleeve (48) concentric therewith, in which arrangement, the inner and outer sleeve (46, 48) consist of different materials and are mechanically rigidly connected to each other.
2. An apparatus according to claim 1, in which arrangement the/each pressing-on roller (12) is provided with an adjustment device (16) for the defined setting of the spacing of the corresponding pressing-on roller (12) relative to the embossing roller (20), and hence for the defined setting of the pressure exerted on the embossing sheet and the material web, characterized in that the inner bush (32) is mounted by means of bearing devices (34) on a cam section (30) of a bearing pin (26) of the adjustment device (16), arranged for rotation on a bearing block (14) .
3. An apparatus according to claim 2, characterized in that the/each pressing-on roller (12) is narrow as compared with the embossing roller (20), and is linearly adjustable with the associated bearing block (14) on a bearing bracket (18) disposed parallel to the axial direction of the embossing roller (20).
4. An apparatus according to one of the preceding claims, characterized in that an annular cover element (58) is provided on each side face of the/each pressing-on roller (12) for sealing the gap (52) between the inner and outer bush (32, 44) in a leakproof manner.
5. An apparatus according to claim 4, characterized in that the cover elements (58) are secured on the inner bush (32) of the corresponding pressing-on roller (12), in which arrangement, the outer sleeve (48) of the outer bush (44) radially projects over the cover element (58).
6. An apparatus according to claim 5, characterized in that the inner bush (32) is axially wider than the outer bush (44), or the inner and outer sleeve (46, 48) of the outer bush (44), so that between each cover element (58) and the associated outer bush (44), or the inner and outer sleeve (46, 48) of the outer bush (44), there exists a gap (68).
7. An apparatus according to claim 6 characterized in that the cover elements (58) are designed on their inner side (62) with a peripheral circular groove (64) wherein there is arranged an annular sealing element (66) projecting into the corresponding gap (68) and bearing on the outer bush (44) with a sealing effect.