ES2252099T3 - RELIEF STAMPING PROCEDURE AND RELIEF STAMPING DEVICE. - Google Patents

Abstract

The method involves pressing a section of a transfer area onto a bearer material in an embossing station, whereby the transfer area is fed into the embossing station in the form of a continuous foil strip (11). Fault points (28-30) in the foil strip are detected by a sensor (27) as it is being fed to the embossing station and fault points are fed between two embossing in the station. An Independent claim is also included for a relief printer.

Description

Embossing procedure and embossing device.

Technical sector and state of the art

The present invention relates to a embossing procedure and a device for Performing the procedure. It is known for example thanks to DE 90 04 865 U1 document a hot stamping machine in which is supplied to a stamping station a continuous sheet which contains a transfer zone, formed by at least one layer to be transferred by embossing.

In this hot stamping machines type is known to orient the continuous sheet with respect to its position, especially the position of a motif that is repeated periodically on the transfer zone, with respect to the point of stamping in the stamping station, in such a way that the motive is transferred accurately position on the material of stamping. The document EP-A-982127 unveils a method according to the preamble of claim 1 and a device according to the preamble of claim 10.

During the use of continuous sheets of this type is however possible that there are points of irregularity in the continuous sheet or in the transfer zone. If this kind of continuous sheet or transfer zone sections arrive at the stamping area, waste is produced. These wastes must be then classified in the subsequent course.

Problem and solution

The present invention aims to reduce Waste manufacturing during embossing.

This objective is achieved through Embossing procedure and using the device embossing according to the invention.

During embossing it is stamped on a stamping station a segment of a transfer zone, consisting of at least one layer, on a carrier material. Area Transfer is supplied at the same time on a sheet Continue to the stamping station. When supplying the sheet continuous to the stamping station is detected, by a detection device, if in the leaf area of the leaf There are irregularities. If the existence of a irregularity point, the supply of the sheet continues towards the stamping station that the point of irregularity is transported between two prints through the stamping station With this the point of irregularity does not reach to the printing area of the printing station so that no waste is generated. At the same time this way of proceeding has the advantage that the processing speed at the station stamping is influenced in any case imperceptibly and the embossing process can be continued at high speed, when the sheet material presents, conditioned for production, irregularity points at regular distances. This is the case, for example, especially in areas of transfer, which have holograms. Holograms they can consist of both individual images, the same which are repeated periodically, as well as gratings of diffraction - where appropriate with a sample inside - which  they are repeated indefinitely on the sheet. These types of sheets are frequently transferred on cardboard and other papers, in Special packaging This happens, on the one hand, to prevent a simple copy of the packaging and, on the other, frequently, because of the optical and tactile effects that can be achieved with it.

On the other hand, the continuous sheets stored on drums, which are used for continuous supply continuous sheet towards the stamping station, always present junction points at which a continuous sheet was joined leaf fragment continues next. These junction points are not They can also avoid conditioned by manufacturing.

According to an advantageous improvement of the invention is detected by the detection device the electric condutibility of the continuous leaf.

According to other advantageous improvements of the invention can be detected, alternatively or additionally, by the detection device one or more properties continuous blade optics. It is especially advantageous to detect The reflection behavior of the continuous sheet. According to another advantageous refinement the reflection behavior is defined by a diffraction grating on the leaf side keep going. For this, the detection device has, according to a advantageous improvement, a laser light source which radiates light directed towards the continuous leaf, where the intensity of The light is detected at a maximum of diffraction. It is concluded that there is an irregularity in the continuous sheet, that is a irregularity in the diffraction grating, when the intensity of light when diverged by a predetermined amount of light intensity that can be expected at this maximum.

According to another advantageous improvement the detection device consists of several sensors, the which are arranged next to each other transversely regarding the transport direction of the continuous sheet and it concludes that there is an irregularity in the continuous sheet when at minus two sensors simultaneously record a signal, which corresponds to the existence of an irregularity in the leaf keep going.

An embossing device according to the invention is formed with a delivery device for the continuous sheet supply with the stamping sheet towards a stamping station of a control device to influence on the continuous sheet supply to the stamping station and sensors for checking the continuous sheet on the side of stamping station supply. At the same time it takes place continuous sheet supply to the stamping station depending on the signals of the control device.

In the case of the printing station it is especially a stamping station that works so rotary, which is formed by a stamping cylinder with a stamping seal and a contact cylinder. At the same time it transfers, only when the seal comes into contact with the continuous sheet, a segment of the transfer zone from the continuous sheet to the carrier material. The carrier material can be supplied either by sheets or as a sheet of material keep going.

The previous and following features are they deduce, in addition to the claims, also from the description and of the drawings, where the individual characteristics can in each case, either alone or for several in the form of subordinate combinations, for an embodiment of the invention, be carried out in other fields and represent forms of advantageous realization as well as susceptible of being protected, for which protection is requested herein. The subdivision of the application into individual sections as well as intermediate titles do not limit their general validity affirmations contained in them.

Brief description of the drawings

An example of embodiment of the invention is represented in the drawing and explained to continuation in greater detail. In the drawings they show:

Fig. 1 shows a representation schematic of a stamping station according to the invention;

Fig. 2 shows an example of the form of realization of an optical detection of irregularities of a leaf holographic, and

Fig. 3 shows the representation Schematic of a holographic sheet.

Description of the figures

Fig. 1 shows the schematic representation of an embossing device according to the invention for performing an embossing procedure according to the invention.

During embossing, the continuous sheet 11 and material sheet 23 to the device embossing pattern 22. The embossing device 22 in the example shown there is a stamping cylinder 24 which has a seal 25 and a contact cylinder 26. Seal 25 of the embossing device 22 can, at the same time, be preheated for hot stamping up to a temperature of predetermined stamping, by means of a heating element not represented. Seal contour 25 protrudes at the same time beyond the outer contour of the stamping cylinder 24. In It is a process of stamping, during which the seal 25 is in contact with the contact cylinder 26, it transfer a segment of the transfer zone from the sheet continue 11 to material sheet 26. To do this they must move the material sheet 23 and continuous sheet 11 during the process of stamping, with the perimeter speed of the stamping cylinder 24, through the embossing device 22.

To maintain continuous sheet consumption so small as possible the continuous sheet supply 11 se can control or regulate in such a way that between two processes of stamping the stamping foil 11 be moved back, in against the transport direction of the material sheet 23, to through embossing device 22 and, to then be accelerated again to the perimeter speed of the stamping cylinder 24, so that the zone segments of transfer removed by stamping are located as next possible from each other. In your case it can be maintained for this process a grid measure, which is defined by marks of position that are on the continuous sheet. This is especially necessary when images need to be stamped out which are applied periodically so that they are repeated on the transfer area of the continuous sheet and therefore it is necessary, during stamping, a precise position reference between the continuous sheet 11 and the material sheet 23. For the realization of this control or regulation, the continuous sheet 11 is transported, by means of the drive roller 12 and the belt Applicant 13, forward and backward, is braked and accelerated. This is controlled by the control device 20.

Between the drive roller 12 and the stamping device 22 is arranged a device detection 27. The detection device 27 is formed by sensors for the detection of the electrical conductivity of the continuous sheet as well as sensors for the detection of diffraction of light by the continuous leaf.

The measurement of electrical conductivity has place at the same time by contact rollers 15, arranged one behind the other in the direction of transport of the continuous sheet  11, which extend essentially along the width of the Transfer zone or continuous sheet. Between the rollers of contact 15, which are formed as electrically rollers conductors, a voltage source 17 is arranged. The ammeter 16 detects the current conducted through the circuit of current with the contact rollers 15 and sends a signal corresponding to the control device 20. The circuit of current between the two contact rollers 15 is closed thereto time through the continuous sheet 11. If the continuous sheet is damaged on its surface or the continuous blade is interrupted or if it is joined by a place of adhesion 28, then the electrical conductivity of the continuous sheet in the area between the two contact rollers 15. In addition, the transfer zone of the continuous sheet, which presents a diffraction sample, especially a diffraction grating that runs transversely with respect to The transport direction of the continuous sheet is illuminated with the laser 18 with light of known wavelength. Through the photoelectric cell 19, which is arranged in the direction of irradiation of the maximum diffraction of nth level, is detected the reflection behavior of the transfer zone. A reduction of the signal intensity in the photoelectric cell 19 is evaluated by the control device 20, which is given supplies a signal that represents the measured intensity of the photoelectric cell 19, as caused by an irregularity in the Continuous sheet transfer zone.

Since the distance of the measuring points with respect to the embossing device 22 is fixed and is a known value, the position of the irregularity point on the continuous sheet 11 with respect to the stamping point, in which a segment of the transfer zone is stamped on the sheet carrier 23, is known. The control device 20 controls or now regulates the advance of the continuous sheet, so that the seal 25 does not come into contact with a sheet section continuous, which presents a point of irregularity. Therefore irregularity points are not transferred on the sheet continued 23. This does not form debris conditioned by irregularities of the continuous leaf.

Fig. 2 shows a continuous sheet 11 which is moved below the detection device 27. The sheet continuous 11 consists of transfer zone 32 and the sheet of position 33. Position sheet 33 has stop marks 31, which define the position of a motif applied so that repeated over transfer zone 32. If the sheet does not present a reason that is repeated, then it is not necessary for the sheet continuous 11 present, in addition to the transfer zone 32, also position sheet 33. Detection device 27 is formed by two pairs of lasers 18 and photoelectric cells 19. Each of the two lasers 18 radiates a ray of light over the area of transfer 32. The two points of light are arranged at same time on the sheet continues transversely with respect to the direction of transport of the sheet with respect to the device detection 27. Photoelectric cells 19 are arranged, with respect to lasers 18 and transfer zone 32 in the irradiation direction of the maximum nth order of the sample Holographic diffraction, which shows the transfer zone 32. For recognition of the position of stop marks 31 on position sheet 33 is arranged in the device additionally detecting a light source 34 and a cell Photoelectric 35. Light source 34 and photoelectric cell 35 they serve at the same time for the detection of the position of the stop marks.

Transfer zone 32 may present to same time different irregularities. In Fig. 2 they are represented as irregularities the grease stain 30, the place of accession 28 as well as the so-called Shim songs 29. The Shim 29 edges are formed, conditioned by manufacturing, during the manufacture of transfer zones which present holographic images, especially a diffraction grating Holographic At the same time the songs Shim 19 are distanced regularly over the transfer zone. If you move now one current source below the detection device 27, then the diffraction of the light beam is disturbed emitted by lasers 18. In the case of a grease stain 30, disturbs only the signal of one of the two at the same time Photoelectric cells 19. The existence of a grease stain or of a similar fouling does not disturb, however, so the suitability of the segment of the transfer zone for the transfer on the carrier sheet. That is why this area of the transfer zone should not be forced as waste and therefore this area of the sheet does not have to be excluded from the stamping transfer on the material sheet. Both a Shim song 29 as well as a place of accession 28 interrupt without However, diffraction in the transfer zone in both cells  Photoelectric 19. A Shim Ridge is an area of the area of transfer 32, which cannot be used for stamping and therefore it must not come into contact with the seal 25 of the cylinder stamping 24 during a stamping process. Since the songs Shim are only very narrow songs can be distinguished, on the time base of the light diffraction interruption in the transfer zone 32, thanks to that, a Shim 29 edge of place of accession 28, which should also be seen as undone, because The duration of the disturbance is recorded. An interruption prolonged diffraction of light in the transfer zone 32 allows us to conclude that it is a place of accession 28. If the continuous sheet 11 also has a position sheet 33, then a place of adhesion may eventually be recognized 28 eventually also because, additionally, the signal of reflection of light source 33 diverges in the photoelectric cell 35, in the area of the place of adhesion, in a way that can be differentiate from stop marks 31.

Fig. 3 shows the representation of a sheet continuous 11. Continuous sheet 11 presents the distance s songs Shim 29. About the size of the seal 25 of the carrier cylinder 24 is knows the length b, which presents a segment of the zone of transfer, which is transferred by stamping using the stamp 25 on the sheet of material 23. After the distance s between two edges Shim 29 is known, you can determine the distance d between two segments 36 such that it is received as many segments 36 as possible between the two shim edges and that, simultaneously, segments 36 are distanced from evenly with respect to each other with distance d. The distance f, between two segments, which contains a Shim edge, at the same time present a general value which is greater than the distance d between two segments 36. At the same time it must be ensured that the distance d cannot be less than a value minimum, which is conditioned by the accuracy of adjustment of the continuous sheet in the stamping device 22 as well as by tolerances and variations of the material during the procedure of hot stamping. In this way an exploitation is possible optimal transfer zone, with a transport speed of the sheet continues simultaneously as uniformly as possible. This This is the case of course only when the transfer zone 32 presents an endless sample and no image whose position should be adjusted with respect to the seal 25 of the stamping cylinder 24. If a Shim song is contained in a sheet that presents an image 29 on the surface of the image, then you have to classify scrap the entire transfer zone section that It contains this image.

Claims (14)

1. Embossing procedure, in which a segment of a zone of transfer is stamped in a stamping station on a carrier material, the transfer zone being supplied in shape of a continuous uninterrupted sheet to the station print, characterized because during the supply of the continuous sheet (11) to the stamping station (22) is detected, by means of a device of detection, irregular points (28, 29, 30) on the sheet continuous (33) and irregularity points are transported to through the stamping station. 2. Embossing method according to claim 1, characterized in that the detection device (27) detects the electrical conductivity of the continuous sheet. 3. Embossing method according to claim 1 or 2, characterized in that the detection device detects optical properties of the transfer zone. 4. Embossing method according to claim 3, characterized in that the detection device (27) detects the reflection behavior of the transfer zone (32). 5. Embossing method according to claim 4, characterized in that the transfer zone (32) has a diffraction grating and the detection device (27) detects irregularities of the diffraction of the light in the diffraction grating. 6. Embossing method according to claim 5, characterized in that the detection device (27) is constituted by a laser light source (18) and a photometer (19) arranged at a maximum of diffraction. 7. Embossing method according to one of the preceding claims, characterized in that the detection device (27) has several sensors, which are arranged transversely offset with respect to the direction of transport of the continuous sheet (f), so that the existence of an irregularity is concluded when a signal corresponding to the existence of an irregularity appears on at least two sensors simultaneously
larity 8. Embossing method according to one of the preceding claims, characterized in that at regular distances (d) a segment (36) of a transfer zone (32) of predetermined length is stamped on the carrier material (23). 9. Embossing method according to claim 8, characterized in that the transfer zone has irregularities (28, 29, 30) at regular distances (s), the maximum number of segments (36) of predetermined length located between two irregularities, and the supply of the continuous sheet to the printing station is carried out in such a way that the maximum number of segments (36) between two irregularities (28, 29, 30) on the continuous sheet (f) is separated (d) evenly with each other. 10. Embossing device particularly hot stamping machine, with a supply device for the supply of at least one sheet continue with a transfer zone, with a transport control device of said at least one continuous sheet through the device of supply with a stamping station, in which a segment of the transfer zone is stamped on a material carrier, characterized because a detection device for checking said at least one continuous sheet is arranged on the supply side of the station station
tamped, making the supply of said at least one continuous sheet in the stamping station using the device of control depending on the detection device. 11. Embossing device according to claim 10, characterized in that the detection device consists of several sensors arranged transversely with respect to the transport direction of the continuous sheet. 12. Embossing device according to claim 10 or 11, characterized in that the stamping station (22) is formed by a stamping cylinder (24) having a seal (25) and a contact cylinder (26). 13. Embossing device according to one of claims 10 to 12, characterized in that the carrier material (23) is supplied as a sheet of continuous material. 14. Embossing device according to one of claims 10 to 12, characterized in that the carrier material (23) is supplied to the sheet stamping station, such that at least one segment (36) must be stamped on each sheet of the transfer zone (32).