ROLLING INSTALLATION WITH MULTIPLE RIDGES

Abstract: A rolling installation for making creases in a web of material, such as cardboard, comprising a pair of rotary rollers (1, 2), each of which is mounted at its two ends in bearings and each of which is provided with roll surfaces by means of which the rollers are rollable with respect to one another leaving a gap (7) between the roll surfaces, one of which rollers is provided with at least one ridge and the other of which is provided with at least one groove, and the rollers are synchronised such that at the location of the gap each ridge is opposite a groove. Multiple parallel ridges (11) are provided on the one roller and corresponding multiple parallel grooves (13) are provided on the other roller in order to form multiple parallel creases in the web of material, at the location of which creases a rounded corner can be formed.

Description: Rolling installation with multiple ridges The invention relates to a rolling installation for making creases in a web of material, such as cardboard, comprising a pair of rotary rollers, each of which is mounted at its two ends in bearings and each of which is provided with roll surfaces by means of which the rollers are Tollable with respect to one another leaving a gap between the roll surfaces, one of which rollers is provided with at least one ridge and the other of which is provided with at least one groove, and the rollers are synchronised such that at the location of the gap each ridge is opposite a groove. A rolling installation of this type is known. The web of material is deformed in the gap between the two rollers by means of an opposing ridge and groove such that a crease remains. The web of material can then easily be folded at the location of such a crease, as is customary in, for example, the production of packaging, in particular, but not exclusively, cigarette packs. Especially in the case of typical consumer products such as a pack of cigarettes, there is a continual search for a new attractive appearance, which is why the so-called "hard box" packaging made of cardboard and the closing flap hingeable about a crease were developed. The aim of the invention is to be able to provide a further developed packaging. Said aim is achieved in that with the abovementioned rolling installation multiple parallel ridges are provided on the one roller and corresponding multiple parallel grooves are provided on the other roller in order to form multiple parallel creases in the web of material, at the location of which creases a rounded corner can be formed. With the rolling installation according to the invention, multiple creases can be produced so close to one another that the finished packaging no longer has any sharp angular transitions but smoothly flowing, rounded corners. Such a flowing character of the corner region between two walls of, for example, a cigarette pack increases the attractiveness to the public, which gives the manufacturer a competitive advantage and makes the packaging more exclusive. A significant advantage of the very small mutual spacing of the creases is that shaping of an evenly curved corner region is no problem whatsoever. Since all creases can be identical, there is no preference for the material to fold at the location of the one crease before folding at another crease, with the result that all creases bend to the same extent through a small fold angle when the packaging is produced. The result is the even, curved progression in the corner regions, which has already been mentioned. The multiple parallel ridges are accommodated on a local elevation on the roller surface. According to a preferred embodiment, which in particular is suitable for cigarette packs, the multiple ridges and grooves are designed to form 7 creases, with a mutual spacing of approximately 0.8 mm. Other numbers and dimensions are also possible. In particular, at least one pair of mutually parallel series of multiple ridges and grooves are provided for forming a pair of multiple parallel creases, it being possible to form a rounded corner at the location of each of said series of creases, on either side of a flat panel. In practice several pairs of series of ridges and pairs of series of grooves are arranged alongside one another on a pair of rollers, in connection with the simultaneous handling of the same number of blanks for packaging. There are two successive pairs of series with ridges and grooves in the circumferential direction of the rollers, which series are some distance apart in the circumferential direction and are joined at the ends thereof located opposite one another by ridges and grooves, respectively, running in the axial direction of the rollers in order to form a packaging box with four rounded corners and an end panel having a width equal to the spacing between the pairs of series. Thus, there are pairs of ridges and grooves distributed over the circumference of the rollers in order to form, in each case, one complete packaging. The ridges can also run transversely to the circumferential direction. The invention also relates to an installation for the production of a blank for forming a box or pack, such as a cigarette pack, comprising a rolling installation as described above, a cutting roller installation provided with a cutting roller with blades, and a contra-roller with stripping pins for the waste material which has been cut out, which stripping pins can be accommodated in recesses in the cutting roller at the location of the gap between the cutting roller and the contra-roller. The material which has been cut off and has become surplus is removed by means of the stripping pins, which are known per se. The aim of this is to reduce the amount of waste as far as possible. As a consequence of this all that remains are thin strips of material, which are difficult for the stripping pins to pick up, at least without tearing the waste. Once the waste tears, pieces thereof get between the rollers, as a result of which the process is disrupted. According to the invention an improvement can be provided in this respect as well in that each stripping pin is accommodated in a block, which block is let into the surface of the contra-roller. The stripping pins now no longer have the traditional threaded stud. Such a threaded stud imposes restrictions on the minimum diameter which is still permissible. According to the invention a smaller diameter can thus be chosen for the stripping pins. Each stripping pin has a widened head which is in contact with a stop on the block, which stop faces the cutting roller. The widened head is locked in place by means of a headless screw, which interacts with screw thread in the sunken hole in which the head is located. Each stripping pin also has a shank provided with a pointed end, the pointed end of the shank protruding from the block. The invention will now be explained in more detail below with reference to an illustrative embodiment shown in the figures. Figure 1 shows a partial view of a pair of rollers for a rolling installation according to the invention. Figure 2 shows a detail of the two rollers. Figure 3 shows a partial view of an installation for the production of a blank. Figure 4 shows a detail of the two rollers in Figure 3. Figure 5 shows a blank. Figure 6 shows a detail of a packaging. The rollers 1 and 2 shown in Figure 1 are rotatably mounted by means of respective stub axles 3, located on either side, in a frame which otherwise is known and is not shown. The rollers are synchronised by means of respective gears 5, 6. The rollers enclose a gap 7 between them, which gap is defined by the respective roll surfaces 8, 9 which roll over one another. Roller 1 has a number of patterns 10 consisting of ridges 11 (see Figure 2), whilst roller 2 has a number of patterns 12 consisting of grooves 13 (see Figure 2). As can be seen in Figure 2, the ridges 11 are located on an elevation 20. As a result a gap 7 can remain clear between the rollers 1, 2. The patterns 10, 12 each define pairs of creases for a cigarette pack, specifically one pair 14 for the front, one pair 15 for the back and one pair 16 for a flap which adjoins the front. The finished blank, as creased by means of the rollers according to Figure 1, is shown in Figure 5. The creases obtained are indicated by reference numerals 17 and the panels obtained are indicated by reference numerals 14', 15', 16'. Figure 6 shows that, for example, there is a transition from back panel 15' via the rounded corner 18 formed by means of said crease lines 17 to side panels 19. The blank shown in Figure 5 has been obtained by cutting out the blank from the web of material, after the crease lines have been made by means of the pair of rollers according to Figure 1, by means of the pair of rollers 21, 22 shown in Figure 3. These rollers are also rotatably mounted by means of stub axles 23, 24, respectively, and roll over one another by means of the roll surfaces 25, 26. Here also the synchronisation is achieved by means of gears 27, 28. As can be seen in Figures 4 and 5, there is a gap 29 between said rollers 21, 22, through which gap 29 the web of material 30, which has been provided with crease lines beforehand, is fed. Roller 21 has a pattern with blades 31, which blades are shown in cross-section on an enlarged scale in Figure 4. The surface of roller 22 is essentially smooth, whilst the cutting edge of the blades 31 extends virtually as far as the surface of the roller 22 at the location of the gap 29. Consequently, the desired cutting pattern in accordance with the blanks can be produced in the web of material 30. In order to be able reliably to remove the residual material from the cut-out blanks, pins 32 are arranged on the roller 22. Said pins have a shank 34 with a sharp point 35, as well as a head 36. The pins 32 are all accommodated in blocks 37. The head 36 is located in the bore 38 of relatively large diameter, whilst the shank 34 extends through the bore 39 of relatively small diameter. The stop face 40, which marks the transition between the bores 38, 39, is such a distance away from the external surface of the block 37 (which external surface is coincident with the external surface of the roller 22 in its entirety) that the sharp point 35 just extends into a recess 41 in the roller 21. The bore 38 is provided with an internal screw thread, such that the head 36 of the pin 32 can be fixed in place by means of the headless screw 42. The blocks 37 are each accommodated in recesses 43 in the surface of the roller 22. They are fixed to the latter by means of bolts 44, which are screwed into holes 45 provided with a screw thread. By virtue of this construction of the pins 32, the latter can be made very thin, as a result of which it is possible accurately to pick up and remove even thin strips of waste from the cut-out blanks.

Claims: Claims 1. Rolling installation for making creases (17) in a web of material (30), such as cardboard, comprising a pair of rotary rollers (1, 2), each of which is mounted at its two ends (3, 4) in bearings and each of which is provided with roll surfaces by means of which the rollers are rollable with respect to one another leaving a gap (7) between the roll surfaces, one of which rollers (1) is provided with at least one ridge (11) and the other (2) of which is provided with at least one groove (13), and the rollers (1, 2) are synchronised such that at the location of the gap each ridge (11) is opposite a groove (13), characterised in that multiple parallel ridges (11) are provided on the one roller (1) and corresponding multiple parallel grooves (13) are provided on the other roller (2) in order to form multiple parallel creases (17) in the web of material (30), at the location of which creases a rounded comer (18) can be formed. 2. Rolling installation according to Claim 1, wherein the multiple parallel ridges (11) are accommodated on a local elevation (20) on the roller surface. 3. Rolling installation according to Claim 1 or 2, wherein the ridges (11) and grooves (13) run in the circumferential direction of the rollers (1, 2). 4. Rolling installation according to one of the preceding claims, wherein the multiple ridges (11) and grooves (13) are designed to form seven crease lines, with a mutual spacing of approximately 0.8 mm. 5. Rolling installation according to one of the preceding claims, wherein at least one pair (14-16) of mutually parallel series of multiple ridges (11) and grooves (13) are provided for forming a pair of multiple parallel creases (17), it being possible to form a rounded comer (18) at the location of each of said series of creases, on either side of a flat panel (14' - 16'). 6. Rolling installation according to Claim 5, wherein two successive pairs of series (14 - 16) with ridges (11) and grooves (13) are provided in the circumferential direction of the rollers, which series are some distance apart in the circumferential direction and are joined at the ends thereof located opposite one another by ridges (46) and grooves (47), respectively, running in the axial direction of the rollers in order to form a packaging box with four rounded comers and an end panel having a width equal to the spacing between the pairs of series. 7. Installation for the production of a blank (48) for forming a box or pack, such as a cigarette pack, comprising a rolling installation according to one of Claims 1 - 6, a cutting roller installation provided with a cutting roller (21) with blades (31), and a contra-roller (22) with stripping pins (32) for the waste material which has been cut out, which stripping pins (32) can be accommodated in recesses (41) in the cutting roller (21) at the location of the gap between the cutting roller (21) and the contra-roller (22). 8. Installation according to Claim 7, wherein each stripping pin (22) is accommodated in a block (37), which block (37) is let into the surface of the contra- roller (22). 9. Installation according to Claim 8, wherein each stripping pin (32) has a widened head (36) which is in contact with a stop (40) on the block (37), which stop faces the cutting roller (21). 10. Installation according to Claim 9, wherein the widened head (36) is locked in place by means of a headless screw (42), which interacts with screw thread in the sunken hole (38) in which the head (36) is located. 11. Installation according to Claim 9 or 10, wherein each stripping pin (32) has a shank (34) provided with a pointed end (35), the pointed end (35) of the shank (34) protruding from the block (37).

Inventors: KOITEK GUENTHER HANS, MADERN JEAN HENRY ROBERT, KOITEK, GUENTHER, HANS, MADERN, JEAN, HENRY, ROBERT
Applicants: KOITEK GUENTHER HANS, MADERN GRAVEERINDUSTRIE EN GER, MADERN JEAN HENRY ROBERT, KOITEK, GUENTHER, HANS, MADERN GRAVEERINDUSTRIE EN GEREEDSCHAPPENFABRIEK B.V., MADERN, JEAN, HENRY, ROBERT
Application year: 1999
Main classification: B67D1
IPC codes: B31F1