Guide device for guiding a printed medium onto a take-up roll in a printing system

Abstract

The present invention provides a guide device for guiding print medium onto a take-up roll in a printing system. The guide device comprises a first guide member presenting a substantially planar surface for limiting or preventing lateral deviation of a printed medium output from the printing system as the medium moves along a transport path towards a take-up roll for winding or taking up a length of the medium. The first guide member is stationary in use. A position of the first guide member is adjustable in a direction transverse to the transport path for setting the position to limit or prevent lateral deviation of the medium along the transport path. The guide device further comprises a second guide member presenting a support surface configured and arranged to support the medium thereon as the medium travels along the transport path towards the take-up roll. The first guide member and the second guide member are preferably integrally formed as a guide unit. Further, the invention provides a printing system which incorporates such a guide device.

Claims

1. A guide device for guiding a print medium onto a take-up roll in a printing system, adjustable to accommodate print media of different widths, comprising: a first guide member comprising a contact surface for contacting a side edge of a printed medium output from the printing system as the medium moves along a transport path towards a take-up roll for winding up a length of the medium; a first actuator for adjusting a position of the first guide member in a direction transverse to the transport path to set the position for a particular medium width; a controller assembly comprising: a sensor for determining a lateral position of a medium on the transport path and generating lateral position data; and a controller for receiving the lateral position data and controlling the first actuator to set the first guide member to the determined lateral position of the medium to prevent lateral deviation of the medium along the transport path.

2. The guide device according to claim 1, wherein the sensor is positioned along the transport path upstream of the first guide member, wherein the first guide member is positioned upstream of the take-up roll.

3. The guide device according to claim 1, wherein the controller is further arranged for adjusting the position of the first guide member between: a media feeding position wherein the first guide member is positioned, such that transport of the medium on the transport path is unimpeded by the first guide member; and an operative position wherein the first guide member is positioned laterally inside the transport path for contacting a side edge of the medium to prevent lateral deviation of the medium along the transport path, and fixing the first guide member in the operative position.

4. The guide device according to claim 1, wherein the first guide member comprises a flange member, wherein the contact surface is provided on the flange member.

5. The guide device according to claim 1, wherein the first guide member comprises a pair of first guide members, the first actuator being arranged for adjusting the position of the pair of first guide members along an axis in a direction transverse to the transport path to limit lateral deviation of the printed medium between the respective contact surfaces of pair of first guide members as the medium travels along the transport path to the take-up roll.

6. The guide device according to claim 5, wherein the controller is further arranged for adjusting the position of the pair of first guide members between: a media feeding position wherein the pair of first guide members is positioned, such that transport of the medium on the transport path is unimpeded; and an operative position wherein the pair of first guide members is positioned laterally inside the transport path with a lateral spacing of similar to a width of the medium for contacting the side edges of the medium to prevent lateral deviation of the medium along the transport path, and fixing the first guide member in the operative position.

7. The guide device according to claim 6, wherein the controller is arranged for positioning the pair of first guide members outside the transport path in the media feeding position.

8. The guide device according to claim 7, wherein the first guide member and the second guide member are integrally formed as a guide unit.

9. The guide device according to claim 6, wherein the support surface of the second guide member is substantially curved to direct or guide the medium through a curve on the transport path.

10. The guide device according to claim 1, further comprising a second guide member presenting a support surface configured and arranged to support the printed medium there-upon as the medium travels along the transport path towards the take-up roll.

11. The guide device according to claim 10, wherein the support surface of the second guide member is configured and arranged to guide the printed medium out of a buffer zone of the printing system towards the take-up roll.

12. The guide device according to claim 1, wherein: the sensor is positioned upstream of the first guide device for determining a first lateral position of the medium; the controller is further arranged to determine: a second lateral position of the medium from the position of the first guide member; and a skewing of the medium with respect to the transport path by comparing the first lateral position and the second lateral position.

13. The guide device according to claim 12, wherein the controller is further arranged for: comparing the determined skewing to a skewing reference; and emitting an alert signal when the skewing exceeds the skewing reference.

14. The guide device according to claim 1, wherein the sensor is a side edge sensor for determining a lateral position of at least one side edge of the medium on the transport path.

15. A printing system comprising a guide device according to claim 1, further comprising a buffer zone for forming a blouse in the medium, wherein the buffer zone is positioned between the sensor and the first guide member.

16. A method for guiding print a medium onto a take-up roll in a printing system, the method comprising the steps: a sensor determining a lateral position of the medium on a transport path of the printing system and generating lateral position data; a controller receiving the lateral position data and controlling a first actuator to set a first guide member to the determined lateral position, the first guide member comprising a contact surface for contacting a side edge of a printed medium output from the printing system as the medium moves along the transport path towards a take-up roll for winding up a length of the medium; and setting the first guide member to the determined position to prevent lateral deviation of the medium along the transport path.

17. The method according to claim 16, wherein the step of determining the lateral position comprises determining a lateral position of a side edge of the medium.

18. A method for detecting skew of a web medium, the method comprising the steps: a sensor determining a first lateral position of the medium on the transport path; transporting the medium from the sensor along a contact surface of a first guide member positioned along the transport path to prevent lateral deviation of the medium, the first guide member comprising a contact surface for contacting a side edge of a printed medium output from the printing system as the medium moves along the transport path towards a take-up roll for winding up a length of the medium; determining a second lateral position of the medium from a position of the first guide member; and comparing the first lateral position and the second lateral position to determine skewing of the medium.

19. The method according to claim 18, further comprising the steps of: comparing the determined skewing of the medium to a skewing reference; emitting an alert signal when the determined skewing exceeds the skewing reference.

20. The method according to claim 18, further comprising the step of transporting the medium from the first guide member to a take-up roll.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) The present invention will become more fully understood from the detailed description given herein below and the accompanying drawings which are given by way of illustration only, and thus are not limitative of the present invention, and wherein:

(2) FIG. 1 is a schematic side view of an output end region of a printing system according to an embodiment of the invention including an apparatus for assisting change-over of take-up rolls, a guide device for guiding printed medium or medium to a take-up roll, and an apparatus for handling the take-up rolls;

(3) FIG. 2 is a schematic perspective view of a guide device for guiding printed medium or medium onto a take-up roll in a printing system according to an embodiment of the invention;

(4) FIG. 3 is a schematic perspective view of a guide device for guiding printed medium or medium onto a take-up roll in a printing system according to an embodiment of the invention;

(5) FIG. 4 is a schematic perspective view of a printing system according to another embodiment of the invention; and

(6) FIG. 5 is a diagram illustrating the various steps of the present invention.

(7) The accompanying drawings are included to provide a further understanding of the present invention and are incorporated in and constitute a part of this specification. The drawings illustrate particular embodiments of the invention and together with the description serve to explain the principles of the invention. Other embodiments of the invention and many of the attendant advantages of the invention will be readily appreciated as they become better understood with reference to the following detailed description.

(8) It will be appreciated that common and/or well understood elements that may be useful or necessary in a commercially feasible embodiment are not necessarily depicted in order to facilitate a more abstracted view of the embodiments. The elements of the drawings are not necessarily illustrated to scale relative to each other. It will further be appreciated that certain actions and/or steps in an embodiment of a method may be described or depicted in a particular order of occurrences while those skilled in the art will understand that such specificity with respect to sequence is not actually required. It will also be understood that the terms and expressions used in the present specification have the ordinary meaning as is accorded to such terms and expressions with respect to their corresponding respective areas of inquiry and study, except where specific meanings have otherwise been set forth herein.

DETAILED DESCRIPTION OF EMBODIMENTS

(9) The present invention will now be described with reference to the accompanying drawings, wherein the same reference numerals have been used to identify the same or similar elements throughout the several views.

(10) With reference now to FIG. 1 of the drawings, a printing system 100 according to a preferred embodiment and comprising an apparatus 1 for assisting change-over of take-up rolls R for taking up printed medium M is illustrated. The apparatus 1 includes a further guide device 2 comprising a panel-like guide member 3 for directing or guiding a medium M of printed media which is output from the printing system 100 along a transport path P towards a take-up roll R for winding or taking up a length of the printed medium M. The take-up roll R typically comprises a tubular or cylindrical roll core formed of cardboard or plastic or any other suitable material, which is mounted in a take-up position P.sub.T in the printing system 100 and is driven in rotation about its central longitudinal axis C for winding or taking up the printed medium M on the roll R. Thus, the printed medium M which is output from the printing system 100 via the apparatus 1 moves along the transport path P by virtue of both pushing forces imparted to the medium M by feed rollers (not shown) as well as pulling forces imparted to the medium M, for example, by the driven take-up roll R.

(11) The apparatus 1 may further include a cutting device (not shown), such as a knife or a blade, for cutting the printed medium M transversely across a width thereof to terminate or to define a length of the medium M to be wound or taken up onto the take-up roll R. In particular, when the take-up roll R is detected to have reached its capacity or when the print job is detected as having finished, the cutting device is controlled and operated to cut the medium M to end the length of that printed medium M to be wound onto the current take-up roll R. The step of cutting the continuous medium M in this way therefore forms a trailing edge region E.sub.T and a new leading edge region E.sub.L of the printed medium M. Under the influence of both the pushing forces and pulling forces imparted to the medium M, both the trailing edge region E.sub.T and new leading edge region E.sub.L of the printed medium M continue to travel along the transport path P downstream of the cutter device towards the take-up roll R.

(12) Referring still to drawing FIG. 1, the apparatus 1 includes a first clamping device 5 having a pair of opposed first clamping members or first jaw members 6, 6 which are movable relative to one another between an open position (shown) to allow the medium M to travel along the transport path P towards the take-up roll R, and a closed position to clamp and hold the new leading edge region E.sub.L of the medium M. In particular, the first clamping device 5 is configured to hold the new leading edge region E.sub.L of the printed medium M against movement along the transport path P towards the take-up roll R. The further guide device 2 is configured to cooperate closely with the first clamping device 5 in this regard. Specifically, the panel-like guide member 3 which extends beneath the printed medium M and directs the medium M along the transport path P to the take-up roll is mounted for pivoting movement about a hinge axis between a first position (not shown) and a second position G.sub.2. In this way, when the jaw members 6, 6 of the first clamping device 5 close to hold the new leading edge region E.sub.L of the medium M, the guide panel 3 can be moved or pivoted to redirect the printed medium M output from the system 100 to a buffer zone B, where the medium M then collects or accumulates temporarily in one or more loose folds (known as a blouse).

(13) On the left side of FIG. 1, the printed medium M extends horizontally to and over the further guide device 2. From there the medium M bends or curves downwards into the buffer zone B. In the buffer zone B, the medium M is folded at least once. After this fold, the medium is directed upwards to the guide device 20. Thus, a U-shaped region of the medium M is formed in the buffer zone B. The medium M further curves or folds over the guide device 20. After the guide device 20, the medium M is transported downwards to the take-up roll R. The guide devices 2, 20 are arranged for suspending the medium M in an S-shaped form. This S-shaped blouse decouples one end of the medium in the blouse from its other end. No forces are transmitted across the buffer zone B ensuring an undisturbed printing process and thereby a high quality print. Also, the medium M after the buffer zone B may be wound onto the take-up roll R free of tension. This reduces the chance of damaging the medium M by contact with the flanges 22, 22.

(14) The further guide device 2 and the first clamping device 5 are operated by a control unit or controller 7 which typically includes a processor and one or more sensors (not shown). After the knife or blade of the cutting device cuts the medium M, both the trailing edge region E.sub.T and new leading edge region E.sub.L at the cut continue to move along the transport path P towards the take-up roll R. A sensor, such as an optical sensor, positioned on or adjacent to the first clamping device 5 may be configured to detect the new leading edge region E.sub.L of the medium M. Upon detection of the cut or the leading edge region E.sub.L within, or just downstream of, the jaw members 6, 6, the controller 7 may activate the first clamping device 5 to close and thereby clamp and hold the leading edge region E.sub.L and then also to move the panel member 3 of the further guide device 2 to the second position G.sub.2 to redirect the medium M emerging from printing heads or from a drying and fixing portion of the printing system 100 to the buffer zone B. At the same time, the take-up roll R is still driven in rotation about the axis C to wind up the final portion of the printed medium M having the trailing edge region E.sub.T formed by the cut. An attachment device (not shown) is provided adjacent the take-up roll R to fix or secure the trailing edge region E.sub.T of the medium M to the roll. In this way, the finished or fully-wound take-up roll R is then ready to be removed or discharged from the take-up position P.sub.T and replaced by a new take-up roll R. This may be performed manually by an operator intervention and/or automatically. After the new take-up roll R is mounted in the take-up position P.sub.T, the new leading edge region E.sub.L of the medium M can be released from the first clamping device 5 and the medium M fed or drawn out from the buffer zone to be wound onto the new take-up roll R. Once the buffered portion of the medium is taken up on the roll R, the guide panel 3 is operated to be pivoted back into the first position G.sub.1 to guide the printed medium M along the transport path P towards the take-up roll R as before.

(15) The embodiment in FIG. 1 further includes a second clamping device 10 having a pair of opposed second clamping members or second jaw members 11, 11 which are movable relative to one another between an open position (shown) to allow the medium M to travel further along the transport path P onto the take-up roll R, and a closed position for holding the trailing edge region E.sub.T of the medium M. In particular, the second clamping device 10 is configured to hold the trailing edge region E.sub.T of the printed medium M against movement while the take-up roll R continues to be driven in rotation to apply tension to the medium and draw the roll R taught as the winding or taking up of the printed medium M is completed immediately prior to the attachment device (not shown) or operator securing the free trailing edge region E.sub.T to the roll R. In this way, as the first clamping device 5 grips and holds the new leading edge E.sub.L of the medium M and the further guide device 2 is controlled to redirect the emerging printed medium to the buffer zone B, the second clamping device 10 is activated by the controller 7 when a not shown sensor (such as optical sensor) provided on or adjacent to the second clamping device 10 detects the trailing edge region E.sub.T of the medium M approaching the take-up roll R, e.g. within or adjacent to the second jaw members 11, 11. The second clamping device 10 may thus cooperate with the attachment device to ensure that the take-up roll R is wound and completed as a taught and compact and secure package of printed medium M from the printing system 100 ready to be removed or discharged from the take-up position P.sub.T and replaced with a new take-up roll R.

(16) With reference now to FIG. 1 of the drawings, an apparatus 30 for handling (i.e. loading and unloading) the take-up rolls R in the printing system 100 is shown schematically. The apparatus 30 includes a holder device 32 mounted on a frame 33 of the apparatus 30 for holding a take-up roll R in a take-up position P.sub.T, such that the take-up roll R is able to rotate about its central longitudinal axis C in the take-up position P.sub.T for taking-up printed medium M output from the printing system 100. In this regard, the take-up roll R comprises a tubular or cylindrical roll core typically made of cardboard or plastic which is driven in the take-up position P.sub.T to rotate about its central axis C in order to wind up the printed medium M as it emerges from the printing heads or from a drying and fixing portion of the system 100. As can be seen in FIG. 3, the apparatus 30 comprises a roll supply 34 for storing a plurality of take-up rolls R, each of which is provided as a tubular or cylindrical roll core typically made of cardboard or plastic. The roll supply 34 is in the form of a hopper mounted on the frame 33 of the apparatus 30 and is configured to guide or feed each of the rolls R individually, preferably under gravity, to a loading position P.sub.L at or adjacent to the holder device 32.

(17) With reference now also to FIG. 1 of the drawings, the holder device 32 comprises a holder member 35 which is rotatable about an axis O of rotation (i.e. parallel to axis C of the take-up roll R in the take-up position P.sub.T) and includes three separate holding portions 36, namely a first holding portion (top side in FIG. 1), second holding portion (bottom right in FIG. 1), and third holding portion (bottom left in FIG. 1). These holding portions 36 are spaced around the holder member 35 and each is configured to receive and support a take-up roll R thereon. In this regard, each of the holding portions 36 has a respective support surface 37 that generally follows a contour of an outer surface of the take-up roll R supported thereon. Furthermore, each holding portion 36 extends between or includes prong- or finger-like ends or protrusions. The first, second and third holding portions 36 are preferably formed integrally as part of the holder member 35 and are thus configured to move simultaneously with one another.

(18) The holder device 32 is configured so that it is rotatable to release or to discharge the take-up roll R from its position on the holder device 32 when the take-up roll R is full or when a print job is finished. In this regard, rotation of the holder device 32 to release or discharge the full take-up roll R also operates to load a new take-up roll R onto the holder device 32 and into the take-up position P.sub.T. More particularly, when the holder member 35 rotates about an axis (not indicated), the first holding portion then moves from the take-up position P.sub.T to the release position P.sub.R to release or eject the full take-up roll R from the holder device 32 to a collector unit 39. The collector unit 39 is designed to collect the full take-up rolls R that are released or discharged from the holder device 32. In this regard, the collector unit 39 may be configured to receive the full take-up rolls R gently via a gradually sloping guide path 40, which stores the take-up rolls R in a sequence corresponding to the order of their release from the holder device 32.

(19) When first holding portion moves from the take-up position P.sub.T to the release position P.sub.R during rotation of the holder member 35 about the axis O, the second holding portion moves from the loading position P.sub.L to the take-up position P.sub.T and thereby loads or receives a new take-up roll R from the supply 34 onto the holder device 32. As will be apparent from the drawings, when the first holding portion of the holder member 35 rotates from the take-up position P.sub.T to the release position P.sub.R to release or discharge the full take-up roll R from the holder device 32, the third holding portion of the holder member 35 rotates from the release position P.sub.R to the loading position P.sub.L to be position ready for the next take-up roll loading operation.

(20) The apparatus 30 further includes a controller or control unit 41 (which may be combined or integrated with control unit 7 of apparatus 1) to control the movement of the holder device 32. In particular, the control unit 41 includes a sensor 42 for sensing or detecting when a take-up roll R has reached capacity or is full and needs to be changed. In this regard, the sensor 42 may detect the amount of printed medium M already wound onto the take-up roll in the take-up position P.sub.T; for example, via a thickness of the wound amount of the medium M. Alternatively, or in addition, the control unit 41 may include a sensor 43 for detecting or registering when a print job is finished. In any case, the control unit 41 is configured to send control signals to control movement of the holder device 32 based on the data or information provided by sensors 42, 43. By controlling the movement of the holder device 32 in this way to unloadi.e. to release or dischargea full take-up roll R, the take-up roll handling apparatus 30 then automatically operates to load or to receive a new take-up roll R form the roll supply 34 onto the holder device 32 and directly into the take-up position P.sub.T.

(21) The printing system 100 of this embodiment further comprises a guide device 20 for guiding the printed medium M towards the take-up roll R in the printing system, and an apparatus 30 for handling the take-up rolls R, and especially for loading and unloading the take-up rolls R in the system 100.

(22) Thus, referring to FIGS. 2 and 3, a preferred embodiment of a guide device 20 for guiding the print medium, e.g. printed medium M, towards the receiving roll or take-up roll R in the printing system 100 is particularly suitable for wide format roll-to-roll inkjet printing systems which generally employ print web media or substrates having a width in the range of about 1 meter to about 4 meters, and more typically in the range of about 1.8 meters to 3.2 meters. As noted earlier, the take-up roll R typically comprises a tubular or cylindrical roll core formed of cardboard or plastic or other suitable material, which is mounted in a take-up position P.sub.T in the printing system 100 and is driven in rotation about its central longitudinal axis for winding or taking up the printed medium M on the roll. Thus, the printed medium M output from the printing system 100 via the guide device 20 is moved along the transport path P by virtue of pushing forces imparted to the medium M by feed rollers (not shown) as well as pulling forces imparted to the medium M by the driven take-up roll R.

(23) In this embodiment, the guide device 20 comprises a pair of guide units 21, 21 and each guide unit 21, 21 includes a generally flat first guide member 22, 22 (e.g. rectangular in FIG. 2-3, but the guide member 22, 22 may also be other shapes such as circular) which presents a substantially planar surface 23, 23 for limiting or preventing lateral deviation of the medium M output from the printing system 100 as the medium M travels along the transport path P to the take-up roll R for winding or taking up a length of the medium. A position of the first guide member 22, 22 is adjustable in a direction D transverse to transport path P, and the position is able to be set to limit or prevent lateral deviation of the medium M as it travels on the transport path P. In this regard, the first guide member or flange 22, 22 includes an opening or aperture 24, 24 which forms an attachment means via which the guide unit 21, 21 is mounted on a shaft or rod 25 for adjustment of the position along an axis A in the direction D transverse to the transport path P. The axis A is typically a longitudinal axis of the shaft or rod 25 and each first guide member 22, 22 may be able to be positioned along the shaft or rod 25 in the axial direction via its opening or aperture 24, 24. After a position of each first guide member 22, 22 (i.e. of the guide device 20) has been adjusted and set for a particular medium width, the first guide members 22, 22 remain fixed or stationary in use.

(24) Each of the guide units 21, 21 of the guide device 20 in the embodiment of FIG. 3 further includes a second guide member 26, 26 presenting a curved support surface 27, 27 for directing or guiding medium M along the transport path P towards the take-up roll R. That is, the curved support surface 27, 27 of the second guide members 26, 26 is configured and arranged to support the printed medium thereon as the medium M travels along the transport path P towards the take-up roll. To this end, the support surface 27, 27 of each second guide member 26, 26 is desirably at least partially circularly or elliptically curved. It preferably also has low friction properties to promote easy passage of the medium M on the transport path P. In this way, support surfaces 27, 27 of the second guide members 26, 26 are configured and arranged to direct or guide the printed medium M from the buffer zone B of the printing system 100 towards the take-up roll R. Thus, during a change-over of the take-up roll R, the printing system 100 may continue printing by redirecting printed medium M to the buffer zone B until a new take-up roll R is ready to receive the medium M. The medium M collects or accumulates temporarily in one or more loose (e.g. S-shaped) folds in the buffer zone B (i.e. as a blouse). When a new take-up roll core is ready to wind up the folds of printed medium M or blouse from the buffer zone B, the curved support surfaces 27, 27 of the second guide members 26, 26 are designed to direct or guide the medium M from the buffer zone B through a curve in the transport path P defined by the curved surfaces 27, 27 towards the new take-up roll R. As is apparent from FIG. 2, the first guide members or flange members 22, 22 and the curved second guide members 26, 26 are integrally formed in the respective guide unit 21, 21 in this embodiment of the guide device 20. It will be appreciated that the curved second guide members 26, 26 may in another embodiment be separate from the first guide members 22, 22, e.g. static second guide member over which the first guide member may laterally move.

(25) FIG. 4 illustrates a further embodiment of a printing system 101 according to the present invention. The printing system 101 comprises one or more actuators arranged for, preferably automatically, positioning the guide units 121, 121 with respect to the side edges of the medium M. The positions of the side edges of the medium M are sensed by a side edge position sensor 160 provided on the print head carriage 150. Alternatively, the position of a side edge may be derived from a position of the medium (or a specific region thereof) and the dimensions of the medium M, as input to the controller 7, 41. The detected positions of the side edges are communicated to the controller 7, 41, which relays said information to the actuators for the guide units 121, 121. The actuators position the guide units 121, 121 with respect to their respective side edges of the medium M or with respect to a desired lateral position on the transport path P. Thereby, the guide units 121, 121 are aligned with the medium M without manual adjustment by an operator. This allows the operator to facilitate the feeding of the medium M at the loading or front side of the printing system 101 without concern for the position of the guide units 121, 121 at the downstream or rear end of the printing system 101.

(26) The sensor 160 is preferably translatable along the support rail 152 in the width direction D of the medium M. The sensor 160 may be an optical detector, for example a CCD camera or optical scanner already provided on the print head carriage 150 for monitoring the print quality or registration of the print swaths on the medium M. The guide units 121, 121 are moveable in the direction D along the support shaft 125, which forms the axis A. The support surfaces 127, 127 for the medium M are formed by the curved surface of the axis A. In FIG. 4, shaft 125 or the axis A is formed as a half-cylinder, but may also be in the form of a rod with a circular or curved cross-section. The shaft 125 comprises a laterally extending recess for guiding the guide units 121, 121 in the direction D. Thus, the support surfaces 127, 127 of the second guide members 126, 126 as well as said guide members 126, 126 are static or fixed with respect to the print surface 154, while the guide units 121, 121 with their guide members 122, 122 and planar surfaces 123, 123 are translatable in the direction D by the one or more actuators controlled by the controller 7, 41.

(27) Preferably, the guide members 126, 126 are shaped in correspondence to the support surfaces 127, 127. An edge of a guide member 126, 126 adjacent a support surface 127, 127 follows the curvature of said support surface 127, 127. Basically, a support surface 127, 127 and an edge of a guide member 126, 126 adjacent said support surface have a similar radius of curvature (or a similar curvature). For example, when the support surface 127, 127 is a tubular surface formed by a roll, the adjacent edge of the guide member 126, 126 is circular with a radius similar to (but slightly exceeding) a radius of the roll forming the support surface 127, 127. This prevents damage to the medium M.

(28) Alternative to directly transporting the medium M from the guide device 20 to a take-up roll, the medium may be transported to a finishing device (not shown) for applying a treatment to the medium, after which the medium M is transported to the take-up roll. Such a finishing device may comprise a laminator device, a trimmer device, and/or a contour cutter device. Thereby, the medium M may treated before being wound up on the take-up roll.

(29) The controller 7, 41 is configured to laterally adjust or set the positions of the guide units 122, 122 in correspondence to the determined lateral positions of the side edges of the medium M, as derived from the data provided by the sensor 160. The method performed by the controller is illustrated in FIG. 5. Prior to feeding the medium M through the printing system 101, the controller 7, 41 in step I positions the guide units 121, 121 in the media feeding position (MP in FIG. 4). In the media feeding position MP, the guide units 121, 121 are positioned outside the trajectory (indicated by the dashed lines in FIG. 3) of the leading E.sub.L of the medium M. During feeding (step II), there is thus no risk of contact between the guide units 121, 121 and the leading edge E.sub.L. After passing the guide units 121, 121, the leading edge E.sub.L is attached to the take-up roll R (step III). The sensor 160 then determines the positions of the lateral edges of the medium M and the controller 7, 41 subsequently aligns the guide units 121, 121 with these lateral edges based on the sensor data. In step IV, the controller 7, 41 sets the guide units 121, 121 in their operative positions, as indicated by OP in FIG. 3. In the operative positions OP the guide units 121, 121 prevent lateral deviation of the medium M, as the printed medium M is being transported from the buffer zone B past the guide units 121, 121 to the take-up roll R (step V).

(30) In another embodiment, the guide units 121, 121 comprise position sensors (not shown) for determining the lateral positions of the guide units 121, 121, such that the lateral position of the medium M (or its edges) on the support surfaces 127, 127 may be derived there from. The controller 7, 41 is then arranged to compare this downstream lateral position of the medium M to the upstream lateral position determined by sensor 160 to derive a skewing angle of the medium M with respect to the transport path P. Preferably, the controller 7, 41 emits an alert to an operator when said skewing exceeds a predefined threshold stored on the processor 7, 41. Further or alternatively, the controller 7, 41 may then laterally move the guide units 121, 121 (and thus the medium M) to re-align the medium M with the transport path P and correct the skewing. Optionally, the controller 7, 41 may stop or slow the transport and printing of the medium M.

(31) Although specific embodiments of the invention are illustrated and described herein, it will be appreciated by those of ordinary skill in the art that a variety of alternate and/or equivalent implementations exist. It should be appreciated that the exemplary embodiment or exemplary embodiments are examples only and are not intended to limit the scope, applicability, or configuration in any way. Rather, the foregoing summary and detailed description will provide those skilled in the art with a convenient road map for implementing at least one exemplary embodiment, it being understood that various changes may be made in the function and arrangement of elements described in an exemplary embodiment without departing from the scope as set forth in the appended claims and their legal equivalents. Generally, this application is intended to cover any adaptations or variations of the specific embodiments discussed herein.

(32) It will also be appreciated that in this document the terms comprise, comprising, include, including, contain, containing, have, having, and any variations thereof, are intended to be understood in an inclusive (i.e. non-exclusive) sense, such that the process, method, device, apparatus or system described herein is not limited to those features or parts or elements or steps recited but may include other elements, features, parts or steps not expressly listed or inherent to such process, method, article, or apparatus. Furthermore, the terms a and an used herein are intended to be understood as meaning one or more unless explicitly stated otherwise. Moreover, the terms first, second, third, etc. are used merely as labels, and are not intended to impose numerical requirements on or to establish a certain ranking of importance of their objects.

LIST OF REFERENCE SIGNS

(33) 1 apparatus 2 further guide device 3 guide member or panel member 4 cutting device 5 first clamping device 6 first clamping member 6 first clamping member 7 control unit or controller 10 second clamping device 11 second clamping member 11 second clamping member 20 guide device 21 guide unit 21 guide unit 22 first guide member or flange member 22 first guide member or flange member 23 substantially planar surface 23 substantially planar surface 24 opening or aperture 24 opening or aperture 25 shaft or rod 26 second guide member 26 second guide member 27 support surface 27 support surface 30 take-up roll handling apparatus 32 holder device 33 frame 34 roll supply 35 holder member 36 holding portion 36 first holding portion 36 second holding portion 36 third holding portion 37 support surface 38 finger or prong 39 collector unit 40 guide path of collector unit 41 control unit 42 sensor 43 sensor 100 printing system 101 printing system 120 guide device 121 guide unit 121 guide unit 122 first guide member or flange member 122 first guide member or flange member 123 substantially planar surface 123 substantially planar surface 124 opening or aperture 124 opening or aperture 125 shaft or rod 126 second guide member 126 second guide member 127 support surface 127 support surface 150 print head carriage 152 support rail 154 print surface 160 side edge position sensor P transport path D adjustment direction A adjustment axis of guide device R take-up roll or roll core P.sub.T take-up position P.sub.R release position C central or rotational axis of take-up roll B buffer zone G.sub.2 second position of the guide member M Medium OP Operative position MP Media feeding position