ROLLER ARRANGEMENT

Abstract

A roller arrangement for a web processing system, the roller arrangement comprising a roller and at least one rotational shaft having a shaft portion and an attachment portion and wherein the at least one rotational shaft is releasably connectable to the roller.

Claims

1.-12. (canceled)

13. A roller arrangement for a web processing system, said roller arrangement comprising a roller and at least one rotational shaft having a shaft portion and an attachment portion and wherein said at least one rotational shaft is releasably connectable to the roller, wherein the attachment portion comprises first connection means matingly connectable with second connection means arranged on the roller and wherein a coupling between the first and second connection means is controllable by means of pneumatics, hydraulics, mechanics, electronics, magnetism or any combination thereof.

14. The roller arrangement of claim 13, wherein the roller is a printer roller, a creasing roller, or any other roller used in a web processing system.

15. The roller arrangement of claim 13, wherein the first and second connection means comprises between 1 and 5 connection points.

16. The roller arrangement of claim 13, wherein one rotational shaft has a portion with a uniform cross section such as to enable it to be slidably suspended in a sleeve.

17. The roller arrangement of claim 16, further comprising a retraction mechanism arranged to retract said one rotational shaft in a step of disengaging the attachment portion from the roller.

18. The roller arrangement of claim 13, comprising a first rotational shaft releasably connectable to the roller at one end thereof and a second rotational shaft arranged on the second end thereof.

19. The roller arrangement of claim 18, wherein a disengagement of the first rotational shaft from the roller and the second rotational shaft from the roller is selectively and individually controllable.

20. The roller arrangement of claim 13, wherein a suspension for suspending the rotational shaft is directly or indirectly tiltable for the purpose of disengaging the rotational shaft from the roller.

21. Method for replacing a roller of a roller arrangement in a web processing system, the roller arrangement comprising the roller and at least one rotational shaft releasably connected to the roller, comprising disconnecting the roller from the at least one rotational shaft, removing the roller from its position in the web processing system further comprising aligning a new roller with the at least one rotational shaft in the web processing system and connecting the rotational shaft to the roller by a releasable connection.

Description

DETAILED DESCRIPTION

[0028] In Fig.1 a simplified web processing system 100 is shown. A web 102 of packaging material is transferred from a first roller 104 to a second roller 106. Between the first and second roll a creasing unit 108 is arranged. The creasing unit comprises an upper roller 110 having a creasing pattern and a lower roller 112 having a resilient surface or a creasing pattern complementary to the creasing pattern of the upper roll.

[0029] The web of packaging material is clamped between the creasing rollers and thereby a creasing pattern is formed onto the web of packaging material, as indicated by the dotted lines 114.

[0030] Apart from providing lines of weakness the creasing pattern 114 may have a decorative effect, and effect of increasing grippability for a user gripping a packaging container formed from the packaging material, just to mention a few non-exhaustive examples. Following the creasing process the creased packaging material is subject to further processing before being used to form packaging containers.

[0031] FIG. 2 illustrates a packaging container which may be formed from the packaging material processed in FIG. 1 (the creasing pattern would have to be altered). The packaging container has a parallelepiped shape, and each fold used to form corners 122, fins 124 etc. be enabled by one or more creasing lines 126 being part of the creasing pattern 114, or formed by a further creasing process. Again, neither the creasing process nor the formation of packaging containers represent the core of the present disclosure, yet the schematic creasing unit of FIG. 1 may still be used to start a description of an example of the need of the invention according to one or more embodiments.

[0032] A web processing line as the one exemplified in relation to FIG. 1 is in a practical situation a highly complex processing plant which is used for processing of various types of packaging materials which in turn is processed to be used for different types of packaging containers. A processing line is therefore and arrangement having some degree of flexibility. One example may be that the creasing rollers 110, 112 may be replaced if the packaging material should be used for a packaging container having a different format, apart from a normal replacement due to wear. Other rollers may need to be replaced, both as an effect of wear, but more often to accommodate a new type of packaging material used for a new type of packaging container (new in relation to what is currently running in the processing line). A replacement would also necessitate further adjustments in terms of web tension etc. Such replacements may be made several times during a working shift. The processing line, be it a creasing line or a lamination line, processes the web of packaging material at a high speed with extreme precision. For example, printing, creasing and cutting are performed in different stations, yet the operations have to be perfectly aligned. When creasing rollers are to be replaced it is therefore quite a complex operation, where commonly an entire creasing unit comprising creasing rollers, guide rollers is replaced at the same time, i.e. the entire unit is disassembled from the processing line and a new creasing unit is put in its place. Apart from being a time consuming and cumbersome operation the cost of having multiple creasing units available is significant.

[0033] Turning now to the present invention, FIG. 3 illustrates a roller arrangement corresponding to, for example, one of the rollers 110 or 112 (or both) of FIG. 1. The roller arrangement comprises a roller 130 and a rotational shaft 132. The rotational shaft 132 is what will suspend the roller 130 when arranged in the web processing line. The roller 130 may when used be passive, such that both ends of the rotational shaft 132 are suspended by a suitable bearing (not shown), while the drive of the roller 130 is provided by the web passing over it. This may be the typical setup for a guide roller. In situations when the roller performs an actual operation in relation to the web, such as a creasing operation or a cutting operation, one or both of the ends of the rotational shaft 132 may be connected to a drive system.

[0034] In the present disclosure it is suggested that the rotation shaft comprises one shaft portion, 134 and 136 respectively, on each side of the roller shafts, releasably attached to the roller 130. In one or more embodiments only one of the shaft portions may be releasably attached to the roller, yet in the preferred embodiments both rotational shafts are releasably attached to the roller, on either side thereof.

[0035] The effect of this feature is that a roller may be replaced without interfering with the suspension in such a way that the tolerances are maintained. Furthermore the feature enables a reduced downtime in connection with change or replacement of a roller. Also the need of having a separate creasing unit for each setup, such as each type of packaging material, each type of packaging container, etc.

[0036] In FIG. 4 it is shown how the both shaft portions have been released from the roller, thereby enabling for the roller to be replaced or maintained in any other way. The coupling between one or both of the shaft portions (depending on the embodiment) should be of a releasable nature. Though it is not an absolute necessity it is preferred that the coupling is of a quick-release nature that provides a straightforward and reliable coupling with high precision and repetitive behavior, such that any fine tuning associated with a replacement of a roller is reduced to a minimum.

[0037] FIGS. 5 and 6 illustrate more detailed perspective views of coupling portions or attachment portions of the roller (FIG. 5) and the shaft portion (FIG. 6) respectively. The roller attachment portion comprises a number of coupling pins 140, in the specific embodiment there are three coupling pins. The shaft attachment portion comprises coupling inserts 142 in an arrangement being arranged matingly with the coupling pins 140 of the roller attachment portion. The coupling inserts may be controllable chucks (pneumatically controlled, hydraulically controlled, electrically controlled, or controlled in another way) such that the coupling and release of the roller may be remotely and directly controlled. To fulfill requirements of the coupling chucks of the type used in various machining systems may be used. Such chucks may provide the repeatable precision and may be capable of withstanding the high loads and forces that may be present in e.g. creasing systems.

[0038] FIG. 7 shows a further feature that may be used for one or both of the shafts 134, 136, namely a slidable arrangement of one or both of the shafts enabling a retraction (movement in an axial direction) of the shaft in relation to the roller 130. In the specific example one second shaft portion (136—not shown in FIG. 7) may be fixedly arranged in a bearing, such that it may rotate but not necessarily moved in an axial direction, while the first shaft portion 134 may indeed be slidably arranged. A sequence of removing the roller may in the present embodiment comprise the steps of actuating a release of the coupling between the first shaft portion 134 and the roller 130; sliding the first shaft portion 134 away from the roller such as to effect a release; actuating a release of the coupling between the second shaft portion 136 and the roller 130; sliding the roller 130 away from the second shaft portion 136 such as to complete the release. For the roller to be slidable the rotational shaft should preferably have a portion or segment extending in an axial direction having a uniform cross section.

[0039] In other embodiments the order of the steps disclosed may be shifted. For example the second shaft portion may be release first, in which case the first shaft portion may be used to pull the roller away from the second shaft portion. In still other embodiments the first and the second shaft portion may be released from the roller at the same time, or at least before any further steps are initiated.