PROCESS AND DEVICE FOR PREPARING PLATES FOR CYLINDERS TO CREASE ITEMS OF THE PAPER PROCESSING INDUSTRY

Abstract

The invention relates to a process for preparing plates (22, 32) for cylinders (20, 30) to crease items (40) of the paper processing industry, the process comprising the following steps of: a) acquiring a pattern (50) of the creasing lines to be made on the item of the paper processing industry (40); b) making, on a reference sheet (70), through openings (74) depending on the pattern (50) of the creasing lines, the through openings being adapted to position creasing profile elements (25, 35); c) applying the creasing profile elements (25, 35) on the plate (22, 32) at the through openings (74) of the reference sheet (70), the reference sheet being positioned on the plate (22, 32).

Claims

1-15. (canceled)

16. A process for preparing plates for cylinders to crease items of the paper processing industry, the process comprising the following steps of: a) acquiring a pattern of creasing lines to be made on one or more items of the paper processing industry; b) making, on a reference sheet, through openings depending on the pattern of the creasing lines, the through openings being adapted to position creasing profile elements; and c) applying the creasing profile elements on a plate at the through openings of the reference sheet, the reference sheet being positioned on the plate.

17. The process of claim 16, wherein the positioning of the reference sheet on the plate is carried out before said step b) of making the through openings on the reference sheet or is carried out after said step b) of making the through openings on the reference sheet.

18. The process of claim 16, wherein a step of dispensing the creasing profile elements to be applied on the plate is provided by a dispenser.

19. The process of claim 18, wherein a step of making numeral signs on the reference sheet is provided to identify a positioning order of the creasing profile elements.

20. The process of claim 19, wherein a step of activating the dispenser is provided to dispense the creasing profile elements in accordance with the positioning order set by the numeral signs.

21. The process of claim 20, wherein the step of applying the creasing profile elements on the plate at the through openings of the reference sheet occurs in accordance with the positioning order set by the numeral signs.

22. The process of claim 16, wherein the step of making through openings on the reference sheet for the positioning of the creasing profile elements is carried out by a cutting means.

23. The process of claim 16, wherein the step of making through openings on the reference sheet for the positioning of the creasing profile elements provides for the cutting of a perimeter of the through openings or for the cutting of the perimeter of portions, or segments, of the through openings, and for the subsequent removal of the part of a reference sheet enclosed in said perimeter.

24. The process of claim 19, wherein the step of making numeral signs on the reference sheet for identifying the positioning order of the creasing profile elements is carried out by a cutting means.

25. The process of claim 19, wherein a step of displaying the pattern of the creasing lines to be made on the one or more items of the paper processing industry and/or of displaying the numeral signs for the positioning of the creasing profile elements is provided by a screen controlled by a control unit.

26. The process of claim 16, wherein a complementary creasing profile is applied on the creasing profile of male or female type.

27. The process of claim 16, wherein the reference sheet is made of a plastic material.

28. A device for preparing plates for cylinders to crease items of the paper processing industry, wherein the device comprises: a control unit adapted to acquire a pattern of creasing lines to be made on an item of the paper processing industry; a reference sheet; a means for making through openings on the reference sheet depending on the pattern of the creasing lines, wherein said through openings are adapted to position a creasing profile elements; and a supporting table for a plate to be prepared, the creasing profile elements being applied on the latter at the through openings of the reference sheet positioned on the plate.

29. The device of claim 28, further comprising a dispenser for dispensing the creasing profile elements to be applied on the plate.

30. A creasing machine to crease items of the paper processing industry, comprising a plurality of counter-rotating cylinders on both of which a creasing plate is positionable, wherein the machine is combined with the device for preparing plates of claim 28.

Description

BRIEF DESCRIPTION OF THE FIGURES

[0050] Further characteristics and advantages of the invention will be evident by reading the following description provided for illustration purposes and without limitation, with the aid of the figures illustrated in the attached tables, wherein:

[0051] FIG. 1 is a schematic representation of a creasing machine;

[0052] FIG. 2 shows a laser cutting operation of a reference sheet, according to an implementation of the invention;

[0053] FIG. 2a shows a cutaway detail of the reference sheet incised according to the process illustrated in the preceding figure;

[0054] FIG. 3 is an exploded view of a supporting table, a plate and a reference sheet, according to an implementation of the invention;

[0055] FIG. 4 shows a creasing assembly resulting from the assembling shown in the preceding figure;

[0056] FIG. 5 shows the arrangement of a male profile on the creasing assembly of FIG. 4;

[0057] FIG. 6 shows a section of the creasing assembly to which a male creasing profile has been applied, by following the process illustrated in the preceding figure;

[0058] FIG. 7a shows a male profile and a female profile coupled and ready to be applied according to an aspect of the process of the present invention;

[0059] FIG. 7b shows a step of applying a male profile and a female profile, coupled one to another, on a plate placed on a supporting table;

[0060] FIG. 7c shows a male profile viewed from top;

[0061] FIG. 7d shows two male profiles viewed from top and relatively arranged to make two creasing lines tilted one to another by an angle smaller than 90;

[0062] FIG. 8 shows a couple of rollers composed of a first rotating cylinder having a metal plate provided with a male profile coupled to a female profile and of a second rotating cylinder having a smooth metal plate;

[0063] FIG. 9 shows a couple of rollers composed of a first rotating cylinder having a metal plate provided with a male profile and of a second rotating cylinder having a metal plate provided with a female profile; and

[0064] FIG. 10 shows a block diagram of a possible implementation of the process of the invention.

DETAILED DESCRIPTION OF SOME EMBODIMENTS OF THE PRESENT INVENTION

[0065] FIG. 1 schematically represents a creasing machine to crease items of the paper processing industry, such as cardboards and card stocks and the like, according to an implementation of the present invention.

[0066] The creasing is carried out by using a creasing machine 100 comprising a couple of counter-rotating cylinders 10.

[0067] The couple of cylinders 10 is composed of a lower cylinder 20 and an upper cylinder 30 which rotate about their own symmetry axis in opposite direction, by means of convenient moving means not shown.

[0068] On the outer surface of the upper cylinder 31 an upper plater 32 is positioned by fastening means 24, whereas on the outer surface of the lower cylinder 21 a lower plate 22 is positioned by fastening means 24.

[0069] The upper plate 32 and the lower plate 22 are preferably composed of flexible metal elements having, for example, thickness of 0.25 mm, that can be shaped respectively on the outer surface of the upper cylinder 31 and on the outer surface of the lower cylinder 21. Other thicknesses can be used according to the needs. Several materials can be used for making the plates 22, 32, as mentioned they are preferably of metal material, and for example steel.

[0070] On the upper plate 32 creasing profile elements (portions) and in particular male type profiles 35 are constrained, preferably by gluing, whereas on the lower plate 22 creasing profile elements (portions) and in particular female type profiles 25 are glued. Of course the opposite arrangement can also be provided, wherein on the upper plate 32 the female profiles 25 are constrained, whereas on the lower plate 22 the male profiles 35 are constrained.

[0071] The male type profiles 35 form projections on the upper plate 32, whereas the female type profiles form hollows (recesses) on the lower plate 22. The male profiles 35 and the female profiles 25 are preferably made of plastic material, or plastic material with metal core.

[0072] According to a possible embodiment, as for example visible in the top views of FIGS. 7c and 7d, the male and female profile elements comprise a support 38 on which the projecting portion 37 is arranged (for example a straight ridge for forming the male type profile), or on which the hollow (straight seat) is obtained for forming the female type profile. It has to be noted that the support 38 can take different shapes if viewed in top plan view. For example, according to a possible embodiment (such as for example shown in FIGS. 7c, , 7d), the plan shape of the support 38 of a creasing profile element is not rectangular, but shows for example a hexagonal configuration with oblique sides 39 at its ends, that preferably define a corner equal to or smaller than 90. In general, the plan shape of the support 38 of the creasing profile can include at least one tilted side to allow the approaching installation with at least one tilted side of a support 38 of a further creasing profile.

[0073] Preferably, the elements (portions) of male profile 35 and female profile 25 are self-adhesive and are glued to the respective metal plates. In fact, according to a possible embodiment, the male profiles and the female profiles comprise a layer of adhesive material arranged on their outer surface intended to be constrained to the plate. The adhesive layer is preferably protected by a removable film 27 and 27.

[0074] Once the rotation of the couple of rollers 10 has been activated, the interposition of an item of the paper processing industry, such as for example a cardboard 40 or a greeting card or a card stock to make packaging or micro-packaging little boxes or other item of the paper processing industry, among the male profiles 35 of the upper cylinder 32 and the complementary female profiles 25 of the lower cylinder 22, allows the creasing 60 on the cardboard 40 to be carried out.

[0075] Of course, it has to be noted that the distance between the upper cylinder 32 and the lower cylinder 22 can be adjusted depending on the thickness of the cardboard 40 to be worked.

[0076] According to an aspect of the present invention, the gluing of the male (or female) profiles 35 on the upper plate 32 (or on the lower plate) is guided by a reference sheet 70. In other words, the gluing of the portions, or elements, of male (or female) profile 35 on the upper plate 32 (or on the lower plate), is guided by a reference sheet 70.

[0077] As also pointed out in the following, the reference sheet 70 is of sacrificial type, meaning that it is used as a mask to allow the creasing profile elements 25, 35 to be applied on the plates 22, 32 at the through openings 74, and is then removed from the plate.

[0078] The reference sheet 70 can be made of plastic material.

[0079] According to an aspect of the invention, the reference sheet 70 can be made of polystyrene, for example extruded polystyrene, or of polyester. However other plastic materials are possible. The thickness of the reference sheet is conveniently selected to allow the precise and sharp making of the through openings in the sheet itself, preferably by means of laser type cutting means, as it will be seen better in the following. For example, a reference sheet 70 made of polystyrene having thickness of about 3 mm can be used.

[0080] The reference sheet 70 can be glued on the respective metal plate before the machining, and in particular before making the through openings. The gluing is made by glue that doesn't leave residues on the metal plate. Such a gluing aims to keep the relative alignment between the reference sheet 70 and the plate it is applied to. The subsequent separation of the reference sheet 70 from the plate is as easy as removing any semi-adhesive sheet.

[0081] Such as for example shown in FIG. 2, a reference sheet 70, for example a polystyrene sheet, is cut by cutting means, preferably by means of a laser 80. According to an aspect of the invention a laser cutting head is used, for example a laser cutting head preferably moved in a X-Y plan (for example a laser plotter). The movement plane is preferably parallel to the reference sheet 70 on which the through openings are made. The laser cutting head 80 can be advantageously arranged above the supporting table 90 on which the plate having the reference sheet 70 positioned thereon is arranged. The movement of the laser cutting head 80 occurs in a plan parallel to the plan of the supporting table 90.

[0082] A section view of a detail of the reference sheet 70 and of a through opening 74 obtained therein is shown in FIG. 2a. In particular, it has to be noted that the through openings 74 are obtained so that to pass through the reference sheet to form missing portions generally having straight extension, so as to make the underlying plate visible. The cut effected to make the through openings, if effected when the reference sheet is already positioned on the plate, is made so as not to affect and thus not indent the underlying plate.

[0083] It has to be noted that, according to an aspect of the present invention, the making of the through openings preferably by the laser cutting head 80, is carried out by cutting the perimeter of the through openings, or cutting the perimeter of portions or segments of the through openings. The parts of the reference sheet 70 enclosed within the obtained perimeter are removed so as to form said through openings 74 in the reference sheet, thus making the underlying plate exposed for the application of the creasing profile elements 25, 35, i.e. of the portions of male/female profile.

[0084] Advantageously, according to an aspect of the present invention, the pattern of the through openings 74 made on the reference sheet 70 to position the creasing profiles is determined and then made depending on the pattern 50 of the creasing lines. The pattern 50 can be stored in a storage unit 130 combined with a control unit 110.

[0085] As discussed above, the pattern of the through openings 74, and in particular the shape and/or the size of the through openings 74 or their portions or segments, are determined depending on the pattern 50 of the creasing lines intended to be made. The determination of the shape and the size of the through openings 74 can be advantageously carried out by the control unit 110, depending on the pattern 50 of the creasing lines to be made.

[0086] In other words, the pattern of the through openings, and thus the pattern of the creasing profile elements to be applied to the plate via the corresponding through openings, is indeed defined depending on the pattern 50 of the desired creasing lines to be made and is therefore determined or computed starting therefrom.

[0087] For example, the shape and size of the through openings can be determined depending on the shape and size of the creasing profile applied onto the plate. More in detail, for example the size and the shape of the support 38 of the creasing profile (on which the projecting portion or the hollow is obtained) are taken into account for the determination of the shape and size of the through openings 74 for making the creasing lines in accordance with the acquired pattern 50.

[0088] For example, according to an embodiment, the profile shape is not rectangular but of the type shown in FIG. 7c, where a male profile 35 viewed from top is shown.

[0089] In particular, the profile has a projecting portion 37 positioned on a support 38, where the support 38 is not rectangular but has a hexagonal shape with, at its ends, oblique sides 39 defining an angle equal to or smaller than 90, preferably an acute angle smaller than 45.

[0090] According to an implementation of the invention, the cut made by this angle is obtained with a proper tool combined or integral with a profile dispenser 200.

[0091] As visible in FIG. 7d, which shows a top view of a coupling between two male profiles to make two creasing lines tilted one to another, such an angle between the sides 39 allows the projecting portions 37 of the profiles to get closer and to be tilted one to another at angles smaller than 90. By doing so, it is possible for example to make creasing lines with angles therebetween smaller than 90.

[0092] It has to be noted that the creasing lines of the pattern 50 preferably correspond to the projecting portions 37 or hollows (not shown), that are arranged on the support 38. The through openings 74 to be made on the reference sheet, i.e. the missing portions of the reference sheet having generally straight extension, will be made such that the support 38 can be inserted in the same and that the projecting portion 37 (or the hollow) arranged on the support 38 determines the desired creasing line depending on the pattern 50.

[0093] The same concepts related to the support shape can be applied to the female profiles, where a corresponding hollow portion (not represented in the figures for the sake of simplicity) replaces the projecting portion.

[0094] According to an aspect of the present invention, the movement of the laser cutting head 80 and in general of the cutting means, is controlled by the control unit 110 that acquired the pattern 50 of the creasing lines, depending on which the through openings 74 are made on the reference sheet 70.

[0095] It has to be noted as well that, according to an aspect of the present invention, the cutting means and in particular the laser type cutting means 80 can be used to mark, on the reference sheet 70, one or more reference holes 72 and/or reference numerals 73.

[0096] In fact, according to an aspect of the present invention, in a storage unit 130 connected to the control unit 110, numeral signs are stored to identify the positioning order of creasing profiles and said numeral signs can also be made by cutting, preferably laser cutting, the reference sheet 70.

[0097] FIG. 3 shows in exploded view the reference sheet 70, the upper plate 32 and a supporting table 90. As mentioned, according to a possible embodiment the reference sheet 70 is positioned, preferably removably glued, on the respective metal plate before the machining, and in particular before the making of the through openings. The plate 32, on which the reference sheet 70 has been positioned, is fastened to a supporting table 90 by means of reference pins (or pegs) 95 inserted in reference holes 73 of the plate, such as to form an assembly 92 comprising the plate with the reference sheet positioned thereon, the plate in turn being arranged on the supporting table 90, in the following such assembly is also called creasing assembly 92.

[0098] The reference pins or pegs 95 engage with the respective reference holes 73 being on the plate 32, and possibly with the reference holes 72 made in the reference sheet 70.

[0099] The creasing assembly 92 allows the male profiles 35 to be precisely and effectively positioned on the upper plate 32 by exploiting the through openings 74 and the reference numbers 73, where provided.

[0100] As mentioned, according to a preferred embodiment, the step of positioning the reference sheet 70 on the plate is carried out before the step of making the through openings 74 on the reference sheet 70. In such a case, the through openings 74 are preferably carried out on the sheet positioned on the plate that is in turn arranged on the supporting table 90. However, as already discussed above, it is not excluded that the positioning of the reference sheet on the plate could be carried out after making the through openings 74 on the reference sheet.

[0101] According to a possible embodiment, a dispenser 200 is provided and coupled to a control unit 110 for dispensing the elements of the male type and/or female type profiles.

[0102] More in detail, according to a possible embodiment, such as for example depicted in FIG. 5, male profile elements 35 are dispensed by a dispenser 200 coupled to a control unit 110. The control unit 110 is combined with a storage unit 130. The dispenser 200 can dispense creasing profile elements (portions) of a length suitable to be arranged in an established through opening 74, i.e. of the length that allows obtaining an established portion, or segment, of the creasing pattern.

[0103] The control unit 110 determines the dispensing order of the male profile portions 35 by the dispenser 200 and displays, on a screen 140, the reference numeral 96 of the through opening 74 inside which the corresponding profile portion dispensed by the dispenser 200 has to be inserted.

[0104] In this way there is a unique relation between the profile portion dispensed by the dispenser 200, and in particular its length, and the through opening 74 of the polyester sheet 70 inside which it has to be inserted.

[0105] The gluing operation can be carried out by an operator but can be driven by the control unit 110 organizing the dispensing order from the dispenser.

[0106] According to an aspect of the present invention, the gluing operation is driven by the control unit 110 displaying, on a screen 140, the creasing pattern to facilitate the application by the user.

[0107] According to a possible embodiment, the control unit 110 displays on a screen 140 the reference numeralin the example of FIG. 5 the number 2of the through opening 74, in which the male profile portion 35 produced by the dispenser 200 has to be inserted, in order to aid the operator and speed the operations.

[0108] By gluing all the portions (elements) of male profile 35 in the respective through openings 74, the operator completes the male profile 35 depending on the desired pattern of the creasing lines 50 to be made.

[0109] In FIG. 6 a section of the creasing assembly 92 is shown once the male profiles 35 have been introduced in the through openings 74.

[0110] Once the male profiles 35 have been glued on the upper plate 32, the polyester sheet 70 is removed.

[0111] By following the same process used for the upper plate 32, the lower plate 22 can be provided with female profiles 25.

[0112] The upper plate 32 provided with male profiles 35 is detached from the supporting table 90 and fastened to the upper cylinder 30 by the fastening means 24.

[0113] By following the same process used for the upper plate 32, the lower plate 22 can be provided with female profiles 25 and fastened to the lower cylinder 20 by the fastening means 24.

[0114] The described step of preparing the couple of rollers 10 is depicted in FIG. 8 and is carried out with the upper cylinder 30 and the not-rotating lower cylinder 20.

[0115] The male profiles 35 are glued to the upper plate 32 that is positioned by the fastening means 24 on the outer surface of the upper cylinder 31, whereas the female profiles 25 are glued to the lower plate 22 that is positioned on the outer surface of the lower cylinder 21 by the fastening means 24.

[0116] By rotating the couple of rollers 10, the creasing of the cardboard 40 can be carried out.

[0117] In another implementation of the present invention - for example visible in FIG. 7athe female profiles 25 are not applied directly to the lower plate 22 but are coupled to the complementary male type profiles 35. In general, it has to be noted that, according to a possible embodiment, the male/female profiles are coupled together thus one of the two profiles (male or female) is arranged on the plate in the through openings 74 of the reference sheet 70 that is positioned on the plate, carrying the complementary profile coupled thereon. By doing so, the complementary profile is applied on the second plate without the use of a reference sheet for the second plate.

[0118] As visible for example in FIG. 7a, the manufacturer can provide the female profiles 25 already coupled with the respective male profiles 35, possibly with interposition of a removable connecting element 36.

[0119] Such an assembly of elements and in general the male profiles 35 coupled to the complementary female profiles 25, forms a group of complementary profiles 120. The group of complementary profiles 120 can be dispensed in such a coupled configuration by the dispenser 200.

[0120] FIG. 7b shows a step of applying a male profile and a female profile, already coupled one to another, on a plate 32 placed on a supporting table 90.

[0121] The group of complementary profiles 120 is then placed on a mask consisting of the reference sheet 70 positioned on the plate to reproduce the required creasing profile. It has to be noted that the user will select whether to apply the male profile 35 or the female profile 25 of the group of coupled profiles 120 on the plate.

[0122] This solution has the advantage of requiring one mask only and thus only one reference sheet 70 subsequently removed.

[0123] For example, the group of coupled profiles 120 is applied on the plate 32, with the male profile 35 applied on the plate 32 at the through openings 74 of the reference sheet 70 that is positioned on the plate.

[0124] At this point, in order to position the complementary profiles on the second plate and thus to position the female profiles 25 on the lower plate 22, the lower plate 22 can be positioned over the female profiles 25, the two plates can be separated with the respective complementary male and female profiles attached, and the two plates can be mounted, each one on the respective cylinder.

[0125] Alternatively, the plate 32 on which the group of complementary coupled profiles 120 has been applied, with the male profile 35 applied on the plate 32, is fastened to the upper cylinder 30 by the fastening means 24.

[0126] On the lower cylinder 20 the lower plate 22 is positioned by the fastening means 24.

[0127] In FIG. 8, the couple of rollers 10 is shown wherein the upper plate 32 has the group of profiles 120 and the lower plate 22 applied thereon, the lower plate having a smooth surface 125 and being positioned by the fastening means 24 on the outer surface of the lower cylinder 21.

[0128] Finally, as for example shown in FIG. 9, by starting the rotation of the couple of rollers 10, the group of profiles 120 contacts the lower plate 22 and the female profiles 25 are transferred thereon. The gluing the female profiles 25 on the lower plate 22 occurs due to the adhesive being on the female profiles 25.

[0129] Of course, the gluing can be carried out once the protective film (if any) of the profile adhesive has been removed.

[0130] It has to be noted that despite referring to the application on the plate 32 of the male profile 35 having the female complementary profile 25 coupled, the mounting can be provided on the plate 22 of the male profile 35 having the female complementary profile 25 coupled.

[0131] In other words, in a further implementation of the present invention, the group of complementary profiles 120 coupled together can be positioned on the lower cylinder 20. According to this second implementation, at the end of the process for preparing the creasing system 100, the female profiles 25 will be on the upper cylinder 30 whereas the male profiles 35 will be on the lower cylinder 20.

[0132] It has to be noted as well that the female profile 25, having the male complementary profile 35 coupled, can be applied to one of the plates 32, 22 provided with a reference sheet 70, and the complementary profile can be transferred on a plate not provided with a reference sheet.

[0133] Finally, FIG. 10 shows a block diagram of a possible implementation of the process of the invention.

[0134] In particular, the process according to the not limiting possible embodiment of FIG. 10 comprises a step of acquiring, by a control unit 110, for example in a storage unit 130 combined with the same, a pattern 50 of creasing lines. Optionally, such a step can also provide the storage of numeral signs 96 to identify the positioning order of creasing profile elements (block 300).

[0135] These steps can serve for example to acquire a file in one of the known formats, for example the pdf. format, containing a plurality of information such as for example the graphics of the pattern to be printed on the cardboard, a layer with the profile to be die-cut and another layer containing the creasing lines.

[0136] According to an aspect of the invention, in the process, the creasing layer is automatically selected and from the creasing lines the pattern of the through openings 74 to be made is determined, for example the shape (for example hexagonal) and/or the size (for example the length) of the support 38 of the creasing profile to be applied on the plate, in order to obtain one or more creasing lines of the pattern 50, is/are determined. The shape and/or size are used by the cutting means, for example by the laser, to correspondingly cut the through openings in the reference sheet 70. The shape and/or size are also used by the profile dispenser 200 to dispense the profile to be applied on the plate in the corresponding through opening.

[0137] A plate 22, 32 to be prepared is positioned on a supporting table 90 (block 310) with a reference sheet 70 positioned thereon (block 320).

[0138] Subsequently, a step of making the through openings 74 corresponding to the pattern 50 on a reference sheet 70 and being adapted to position the creasing profile elements 25, 35 and of making the numeral signs (block 330) is carried out.

[0139] As mentioned above, the step of positioning the reference sheet 70 on the plate can be carried out before or after the step of making the through openings 74 on a reference sheet 70.

[0140] As mentioned, the step of making the through openings 74 on a reference sheet 70 depending on the pattern 50 is preferably carried out by laser, and in particular a laser head 80 that can be moved in a known way to make the through openings 74.

[0141] A dispenser 200 is therefore actuated through a control unit 110, to dispense the creasing profile elements 25, 35 according to the order stated by the numeral signs 96 (block 340), and the numeral signs are displayed for positioning the creasing profile elements 25, 35 (block 350). It has to be noted that such steps are optional, in fact, the creasing profiles of the desired size can be conveniently and manually cut starting from a continuous profile and their application can be done without the aid of the numeral signs.

[0142] Finally, creasing profile portions (elements) 25, 35 are applied on the plate 22, 32 at the through openings 74 of the reference sheet 70 (block 360).

[0143] The time estimated for preparing 80 creasing segments according to the process of the present invention is 40 minutes; 30 minutes are required for preparing the group of profiles 120 and 10 minutes for mounting the group of profiles 120 on one of the cylinders of the couple of rollers 10. The data shown relate to a particular implementation of the invention and are not limiting of the performances that can be obtained by virtue of the various implementations of the invention.

[0144] As described above, the application of the creasing profiles of a plate can be repeated for applying the complementary profiles on the second plate. However, as discussed above, according to an aspect of the present invention, the male and female creasing profiles can be coupled together and thus a (male or female) profile is applied on a plate by carrying the complementary profile on itself. The complementary profile can be applied on the second plate by arranging the second plate over the profile complementary to the one applied on the first plate (for example by applying the second plate 22 on the female profile 25 in the embodiment of FIG. 7b). By doing so, the complementary profile is applied on the second plate through adhesive, thus avoiding making a reference sheet for the second plate. Alternatively, the application on the second plate of the complementary profile coupled to the male or female profile that has been applied on the first plate, can be carried out by mounting the first plate carrying the group of complementary profiles coupled on a cylinder. By rotating the counter-rotating cylinders, the complementary profile is transferred on the second plate, free from the reference sheet and fastened to the second cylinder.

[0145] Of course, in case the male and female profiles are coupled by an element interposed therebetween, such a possible temporary connecting element is removed upon the separation of the male and female profiles applied on the respective plates.

[0146] Obviously, modifications or improvements suggested by incidental or particular reasons can be made to the previously described invention, without thereby departing from the scope of the invention. For example, it has to be noted that a plurality of through openings are preferably made on the reference sheet for applying the creasing profile elements, however it is not excluded that a through opening is made on the reference sheet for the application of one or more creasing profile elements.