Apparatus and method for handling take-up rolls in a printing system

Abstract

An apparatus for handling take-up rolls in a printing system includes a holder device for holding a take-up roll in a take-up position. The take-up roll is rotatable about a longitudinal axis thereof in the take-up position for taking-up printed sheet output from the printing system. The holder device is movable to release or discharge the take-up roll from the holder device when the take-up roll is full or when a print job is finished. A movement of the holder device to release or discharge a full take-up roll also operates to load a new take-up roll onto the holder device and into the take-up position. A corresponding method of handling take-up rolls in a printing system is disclosed.

Claims

1. An apparatus for handling take-up rolls in a printing system for taking-up printed sheet, comprising: a holder device for holding a take-up roll in a take-up position, wherein the take-up roll is rotatable about a longitudinal axis thereof in the take-up position for taking-up printed sheet output from the printing system, wherein the holder device comprises an outer circumferential surface whereupon a holding portion is provided for supporting an outer surface of the take-up roll, the holding portion being formed as a recess in the outer circumferential surface of the holder device, wherein the holder device is movable to release or to discharge the take-up roll from the holder device when the take-up roll is full or when a print job is finished, and wherein a movement of the holder device to release or discharge a full take-up roll also operates to load a new take-up roll onto the holder device and into the take-up position.

2. The apparatus according to claim 1, wherein the holder device is rotatable to release or discharge the take-up roll from the holder device when the take-up roll is full or when a print job is finished, and wherein a rotation of the holder device to release or discharge a full take-up roll also operates to load a new take-up roll onto the holder device into the take-up position.

3. The apparatus according to claim 1, wherein the holder device comprises a plurality of holding portions, each of which is configured to receive and support a take-up roll, each of the holding portions being respectively movable from a loading position at which the take-up roll is loaded or received onto the holder device to the take-up position, and from the take-up position to a release position at which the take-up roll is released or discharged from the holder device.

4. The apparatus according to claim 3, the holder device including a first holding portion and a second holding portion, wherein the first and second holding portions are configured to move simultaneously with one another, and wherein, when the first holding portion moves from the take-up position to the release position to release or discharge a full take-up roll from the holder device, the second holding portion moves from the loading position to the take-up position to load or receive a new take-up roll onto the holder device.

5. The apparatus according to claim 4, the holder device including a third holding portion, wherein the third holding portion is configured to move simultaneously with the first and second holding portions and wherein, when the first holding portion moves from the take-up position to the release position to release or discharge a full take-up roll from the holder device, the third holding portion moves from the release position to the loading position.

6. The apparatus according to claim 3, wherein each of the holding portions is respectively rotatable from the loading position at which the take-up roll is loaded or received onto the holder device to the take-up position, and from the take-up position to the release position at which the take-up roll is released or discharged from the holder device.

7. The apparatus according to claim 6, wherein a rotation of the holder device from the loading position to the take-up position and a rotation of the holder device from the take-up position to the release position are each comprises a rotation over an angle of approximately 120 around an axis of rotation.

8. The apparatus according to claim 1, further comprising a roll supply, especially in the form of a hopper, for storing a plurality of take-up rolls for taking-up printed sheet, wherein the roll supply is configured to deliver individually each of the rolls stored in the supply to the holder device at the loading position, preferably via a gravity-feed configuration.

9. The apparatus according to claim 1, further comprising a collector unit for collecting the take-up rolls released or discharged from the holder device, wherein the collector unit is configured to store the take-up rolls in a sequence which corresponds to their release from the holder device.

10. The apparatus according to claim 1, wherein each holding portion of the holder device comprises fingers or prongs between which a roll is received and supported, preferably on a support surface which substantially conforms with a surface of the roll.

11. A printing system which comprises the apparatus according to claim 1.

12. The apparatus according to claim 1, wherein the holding device comprises a plurality of holder portions, and the outer circumferential surface of the holder device is provided with a plurality of circumferentially spaced apart protrusions, which extend out of the outer circumferential surface and separate the plurality of holding portions from one another.

13. The apparatus according to claim 1, wherein said holder portion includes a support surface which substantially conforms with an outer surface of the take-up roll.

14. The apparatus according to claim 1, wherein said holder portion is formed by a portion of the outer circumferential surface being recessed toward an axis of rotation of the holder device to thereby form a concave surface, said concave surface being a support surface of the holder portion configured to support the take-up roll along a full length of the take-up roll.

15. A method of handling take-up rolls in a printing system, especially in a roll-to-roll printing system, comprising the steps of: holding a take-up roll in a holder device in a take-up position, whereby the take-up roll is rotatable about a longitudinal axis thereof in the take-up position for taking-up printed sheet output from the printing system, wherein the holder device comprises an circumferential surface whereupon a holding portion is provided for supporting an outer surface of the take-up roll, the holding portion being formed as a recess in the outer circumferential surface of the holder device, moving the holder device to release or to discharge the take-up roll from the holder device when the take-up roll is full or when a print job is finished; whereby moving the holder device to release or discharge a full take-up roll operates to load a new take-up roll onto the holder device and into the take-up position.

16. The method according to claim 15, wherein the step of moving the holder device comprises rotating the holder device to release or discharge the take-up roll from the holder device when the take-up roll is full or when a print job is finished, whereby rotating the holder device operates to load a new take-up roll onto the holder device into the take-up position.

17. The method according to claim 15, wherein the holder device comprises a plurality of holding portions, each of which is configured to receive and support a take-up roll, wherein the step of moving the holder device comprises: moving, especially rotating, each or a respective holding portion from a loading position at which the take-up roll is loaded or received onto the holder device to the take-up position, and from the take-up position to a release position at which the take-up roll is released or discharged from the holder device.

18. The method according to claim 15, wherein the holder device includes a first holding portion and a second holding portion, and wherein the step of moving the holder device comprises: moving the first and second holding portions simultaneously with one another, whereby, when the first holding portion moves from the take-up position to the release position to release or discharge a full take-up roll from the holder device, the second holding portion moves from the loading position to the take-up position to load or receive a new take-up roll onto the holder device.

19. The method according to claim 15, further comprising the steps of: storing a plurality of take-up rolls for taking-up printed sheet in a roll supply, especially a hopper, and delivering each of the rolls stored in the supply individually to the holder device at the loading position, preferably via a gravity-feed configuration.

20. The method according to claim 15, further comprising the step of: collecting the take-up rolls released or discharged from the holder device in a collector unit, whereby the take-up rolls are collected and stored in the collector unit in a sequence which corresponds to their release from the holder device.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) For a more complete understanding of the invention and the advantages thereof, exemplary embodiments of the invention are explained in more detail in the following description with reference to the accompanying drawing figures, in which like reference characters designate like parts and in which:

(2) FIG. 1 is a schematic side view of an apparatus for handling take-up rolls in a printing system according to an embodiment of the invention;

(3) FIG. 2 is a detailed side view of part of the apparatus shown of FIG. 1; and

(4) FIG. 3 is a flow diagram which schematically illustrates a method according to a preferred embodiment of the invention.

(5) 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.

(6) 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

(7) With reference firstly to FIG. 1 of the drawings, an apparatus 1 for handling take-up rolls R for taking-up printed sheet S in a roll-to-roll printing system 100 is illustrated schematically. The apparatus 1 includes a holder device 2 mounted on a frame 3 of the apparatus 1 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 sheet S 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 sheet S as it emerges from the printing heads or from a drying and fixing portion of the printing system 100. The printing system 100 will usually include a buffer region B in which a section of the printed sheet S may accumulate prior to being wound onto the take-up roll R in order to accommodate slight differences in the speed between the rotating take-up roll R and the sheet S as it emerges from the printing heads and/or from the drying and fixing portion of the printing system 100. Between the buffer region B and the apparatus 1 a sheet clamping unit may be present for holding the sheet S or web medium S during a roll changing operation.

(8) As can be seen in FIG. 1, the apparatus 1 comprises a roll supply 4 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 4 is in the form of a hopper mounted on the frame 3 of the apparatus 1 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 2.

(9) With reference now also to FIG. 2 of the drawings, the holder device 2 comprises a holder member 5 which is rotatable about an axis X of rotation (i.e. parallel to the axis C of the take-up roll R in the take-up position P.sub.T) and includes three separate holding portions 6, namely a first holding portion 6, a second holding portion 6, and a third holding portion 6. The holding portions 6, 6, 6 are positioned on the circumferential surface of the holder member 5. These holding portions 6 are spaced around the holder member 5 and each is configured to receive and support a take-up roll R thereon. In this regard, each of the holding portions 6 has a respective support surface 7 that generally follows a contour of an outer surface of the take-up roll R supported thereon. Furthermore, each holding portion 6 extends between or includes prong- or finger-like protrusions 8. The first, second and third holding portions 6, 6, 6 are all formed integrally as part of the holder member 5 and are thus configured to move simultaneously with one another.

(10) The holder device 2 may be arranged to support a take-up roll R along the full length of the take-up roll R. Preferably, the holder device 2 is arranged to support the take-up roll R at at least two spaced apart positions. These positions may be spaced apart more than the width of the sheet S, such that the holder device 2 supports the take-up roll R at either side of the sheet S during take-up. The holder device 2 may support the take-up roll R or roll core R directly or may support the take-up roll R by supporting a roll core holder inserted into the take-up roll R. Such a roll core holder may comprise driving means for driving the rotation of the take-up roll 2. Alternatively, the take-up roll R may be driven directly.

(11) The holder device 2 is configured such that it is rotatable to release or to discharge the take-up roll R from its position on the holder device 2 when the take-up roll R is full or when a print job is finished. In this regard, a rotation of the holder device 2 to release or discharge the full take-up roll R also operates to load a new take-up roll R onto the holder device 2 and into the take-up position P.sub.T. More particularly, when the holder member 5 rotates about the axis X, the first holding portion 6 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 2 to a collector unit 9. The collector unit 9 is designed to collect the full take-up rolls R released or discharged from the holder device 2. In this regard, the collector unit 9 is desirably configured to receive the full take-up rolls R gently via a gradually sloping guide path 10, which stores the take-up rolls R in a sequence corresponding to the order of their release from the holder device 2.

(12) When the first holding portion 6 moves from the take-up position P.sub.T to the release position P.sub.R during rotation of the holder member 5 about the axis X, the second holding portion 6 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 4 onto the holder device 2. As will be apparent from the drawings, when the first holding portion 6 of the holder member 5 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 2, the third holding portion 6 of the holder member 5 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.

(13) The apparatus 1 shown in the drawings further includes a control unit 11 to control the movement of the holder device 2. In particular, the control unit 11 includes a sensor 12 for sensing or detecting when a take-up roll has reached capacity or is full and needs to be changed. In this regard, the sensor may detect the amount of printed sheet S already wound onto the take-up roll in the take-up position P.sub.T; for example, via a thickness t of the wound amount of the sheet S. Alternatively, or in addition, the control unit 11 may include a sensor 13 for detecting or registering when a print job is finished. In any case, the control unit 11 is configured to send control signals to control movement of the holder device 2 based on the data or information provided by sensors 12, 13. By controlling the movement of the holder device 2 in this way to unloadi.e. to release or dischargea full take-up roll R, the apparatus 1 then automatically operates to load or to receive a new take-up roll R form the roll supply 4 onto the holder device 2 and directly into the take-up position P.sub.T.

(14) Finally, referring to FIG. 3 of the drawings, a flow diagram is shown that illustrates schematically the steps in a method of handling take-up rolls R in a printing system 100 according to the preferred embodiment of the invention described above with respect to drawing FIGS. 1 and 2. In this regard, the first box i of FIG. 3 represents the step of holding a take-up roll R in a holder device 2 in a take-up position P.sub.T. The take-up roll R is rotatable about its central longitudinal axis X in the take-up position P.sub.T for taking-up the printed sheet S output from the printing system 100. The second box ii represents the step of sensing or detecting when the take-up roll R is full of printed sheet and/or when the print job is finished; for example via sensors 12, 13 connected with control unit 11. The third box iii then represents the step of moving the holder device 2 to release or to discharge the take-up roll R from the holder device (2) when the take-up roll R is full or when a print job is finished. This may, for example, involve rotating the holder device 2 via the control unit 11 such that a first holding portion 6 of the holding device in or on which the take-up roll R is held and supported moves to a release position P.sub.R in which the take-up roll R is released or discharged to the collector unit 9. The final box iv in drawing FIG. 3 then represents the step of simultaneously moving the holder device 2 to load a new take-up roll R onto the holder device 2 and into the take-up position P.sub.T as the holder device 2 releases or discharges the full take-up roll R. In this regard, the movement (e.g. rotation) of the holder device 2 preferably occurs as a single movement.

(15) 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.

(16) 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

(17) 1 apparatus 2 holder device 3 frame 4 roll supply 5 holder member 6 holding portion 6 first holding portion 6 second holding portion 6 third holding portion 7 support surface 8 finger or prong 9 collector unit 10 guide path of collector unit 11 control unit 12 sensor 13 sensor 100 printing system R take-up roll or roll core S printed sheet C central or rotational axis of take-up roll B buffer region X rotational axis of holder device P.sub.T take-up position P.sub.R release position P.sub.L load position t thickness