EP3216730B1 - Device for unwinding or winding a sheet of material from or on a winding core - Google Patents

Description

The present invention relates to an apparatus, in particular for an inkjet printer, for unwinding or winding a material web from or onto a winding core, the apparatus comprising a frame with a support means for the winding core and means for positioning the winding core on the support means.

At this point, some terms used in this document should be defined in advance:
The term "material web" in the context of sheet material, preferably a full-surface material such as paper or a fabric-like material such as textile fabric or polyester fabric as a roll, understood with certain bandwidth, which material is particularly suitable as a recording material for inkjet printing.

The term "means" is to be understood in the context that contextually both the singular and the plural of the term may be meant.

In the prior art devices for printers for unwinding a web of material from a winding core are disclosed, which have a frame with two idle end rollers as support means. A holding device is arranged on the frame, with which the roll of material strip is supported rotatably directly on the end rollers, wherein during the development, the holding device permits a unidirectional translational movement of the axis of rotation of the winding core, such that the material web roll always remain in direct contact with the two end rolls during unwinding can.

Such devices are suitable to handle webbing rolls having a relatively large width of, for example, 5 meters, as with the aid of the support means a deflection of the winding core can be prevented, so that the required straightness of the web is ensured. In contrast, the Straight running in devices in which a rotatably connected to the winding core and rotatably mounted on a frame drive shaft has both the Stützals and drive function held for material rolls of tape, which have a width of 5 meters, not always technically guaranteed.

In an exemplary printer, a web typically passes through three sections. The first section comprises a device for unwinding the material web from the winding core, a dancer roller and at least one deflection roller over which the material web is guided. The second section comprises, for example, one or more printing modules for printing the material web and a support plate associated therewith for supporting the material web to be printed, which has a constant distance from the modules. The support plate itself can be designed as a vacuum pressure support plate, with which the material web is temporarily fixed by the plate is subjected to vacuum by means of vacuum generating means. As the last and third sections, the printer may comprise one or more deflection rollers, over which the material web is guided, as well as a further device for winding / unwinding the material web.

The printing modules may be arranged in the second section on a print carriage which may be configured to be scanned in a predetermined manner in one dimension bidirectionally across the entire width of the web during which a print line is printed. When a line is finished, the roll of material rolls is continued one line wide and printing of another line can be started. In this case, the supply of the material web from the first section to the second section can be effected stepwise by position control of the dancer roller during which the material web is fixed in the second section by means of a vacuum support plate.

Some of the known device for unwinding a material web are equipped with a brake device with brake disk and brake shoes, which can act on the winding core with a predetermined torque. During braking, a torque acting on the brake disc is transmitted via the contact pressure of suitable brake shoes. The braking process itself takes place in such a way that during the processing, the contact pressure is not is controllable. An initially set contact pressure can thus only take place before start-up, ie before unwinding, and not during such braking devices.

It is known that both the material web and the roll of material web exposed during the processing of different forces and loads.

On the material web acts a tensile stress, which ensures that it is transported in the desired direction of transport. With the help of the braking device, the winding core is acted upon by a torque, so that it can be controlled and tightly unwound.

However, due to the direct support of the roll of material strip on the two rolls, the wound material web is exposed along its entire width to a line load emanating from the end rolls. In the Abwieglung it comes on the basis of a, more or less large, contact pressure and compression of the roll of material roll, which sooner or later damage, such as a crumpling, can cause the web.

Bidirectional operation, although not known, would amplify the problem mentioned. Demensprechend would increase the risk of possible damage.

At present, the solution to the problem of unidirectional operation is to expose the strip material to such a high tensile stress, at least in the first section of a printer, that it is always tight on the roll. For thin materials, however, the known solution is not suitable because there is a real risk that they break.

Another known solution is to place the rollers an endless belt and to lay the roll of material roll freely on this endless belt between the rollers. The endless belt nestles in the support area and the circumference of the roll of material roll on which only a surface load and no longer the problematic line load acts. The problem with this solution, however, is that due to the inertia of the roll of material roll, once rotated, this danger of rolling over the support area and the rolls in an abrupt stop, or to cause a strip of material tape.

The EP0826615A1 revealed in the FIGS. 1 and 2 a device for unwinding or winding up a material web (3) from or onto a winding core (4), wherein the device comprises a supporting device with bearing surface for the jacket of the cylinder formed by wound parts (2) of the material web (3) on the winding core and the supporting device is designed so that the bearing surface under load of the applied cylinder is concave in the region of the support to the mantle of the cylinder and when rotating the cylinder a synchronous Mitlauf is enabled, wherein the device in the axis of rotation of the winding core engaging means for positioning (5, 6), which allow at least a horizontal positioning of the cylinder, wherein the device comprises a drive means (30) for driving the cylinder.
The object of the present invention is to provide an alternative to the above device, simple device for unwinding a web of material from a winding core. document FR 2 076 500 discloses a device for winding a material web, which comprises a concave support surface for the roll of material and is designed with engaging in the axis of rotation of the winding core means for positioning.

The object is achieved by the features of independent claim 1. The subclaims describe preferred variants of the present inventive device.

According to the invention, a device is provided for unwinding or winding up a material web from or onto a winding core, wherein the device comprises a supporting device with bearing surface for the jacket of the cylinder formed by wound parts of the material web on the winding core and the support device is designed such that the Support surface under load of the applied cylinder is concave in the area of the support to the jacket of the cylinder and a synchronous caster is enabled upon rotation of the cylinder, wherein the device comprises in the axis of rotation of the winding core engaging means for positioning, which at least a horizontal positioning of the cylinder allow, wherein the device comprises one or two drive means, characterized in that the winding core directly or indirectly with in each case one rotatably mounted on the means for positioning connection means is engageable, wherein the one or more drive means can act on the winding core bidirectionally directly or indirectly via at least one of the two connection means with a predetermined torque or can, in such a way that the material web off or can be wound up.

The device according to the invention is particularly suitable as a development device for an inkjet printer.

• Figur 1 zeigt eine Querschnittsansicht einer besonders bevorzugte Ausgestaltung der erfindungsgemässen Vorrichtung 101.
• Figur 2 zeigt eine Querschnittsansicht der besonders bevorzugten Ausgestaltung der Vorrichtung 101 aus Figur 1, die den Wickelkern 105 in einer materialbeladenen und -losen Wickelposition (P1,P2) darstellt.

The invention will be described below with reference to the figures in detail and by way of example.

• FIG. 1 shows a cross-sectional view of a particularly preferred embodiment of the device 101 according to the invention.
• FIG. 2 shows a cross-sectional view of the particularly preferred embodiment of the device 101 FIG. 1 which represents the winding core 105 in a material-loaded and -less winding position (P1, P2).

FIG. 1 shows a device 101 for unwinding \ winding a material web 103 of a winding core 105, the device 101 having a frame 108 with support means 107 for the winding core 105 and means for positioning 109 thereof on the support means 107, wherein the material web 103 tangentially of the material laden Winding core 105 and / or can be wound, wherein the support means 107 comprises a support surface which is formed under load of the winding core 105 as a concave support surface and is movable, wherein the means for positioning 109 holds the winding core 105 perpendicular to its axis of rotation parallel movable ,

In FIG. 1 the support surface is formed by an endless belt 113, which is guided over two idle end rollers 111, which are aligned parallel to the axis of rotation A (not shown) and are rotatably mounted on the frame 108 respectively. The means for positioning 109 is formed as a pivot arm, which on a first end has a rotatably mounted connection means 116 which is directly or indirectly engageable with the winding core 105. The swing arm itself is rotatably mounted on the frame 108 at the second end. The pivot arm comprises at its two ends in each case a drive gear 117, 117 ', over which a circumferential chain 115 is guided, wherein a tensioning gear 119 is provided, which can engage between the gears 117 and 117' in the chain 115.

The drive gear 117 can be driven by a drive means (not shown), which can act on the winding core 105 bidirectionally with a predetermined torque directly or indirectly via the connection means 116 in order to be able to take off or wind up the material web 103.

On the frame 108 feet 121 are attached.

FIG. 2 shows a cross-sectional view of the particularly preferred embodiment of the device 101 FIG. 1 which represents the winding core in a material-loaded and -less winding position (P1, P2).

A device 101 for unwinding or winding up a material web 103 from or onto a winding core 105 has been disclosed, wherein the device 101 comprises a supporting device 107 with bearing surface for the jacket of the cylinder formed by wound parts of the material web 103 on the winding core 105 and the Support device 107 is configured so that the bearing surface under load of the applied cylinder is concave in the region of the support to the mantle of the cylinder and a synchronous Mitlauf is possible during rotation of the cylinder.

According to the invention, the device comprises positioning means 109 engaging in the axis of rotation of the winding core 105, which enable at least horizontal positioning of the cylinder.

In a preferred embodiment of the invention, the support surface is bidirectionally movable.

In another preferred embodiment of the invention, the means for positioning 109 as two parallel to the rotational axis of the winding core 105 mutually displaceable on a frame 108 arranged pivot arms are formed, which are rotatably mounted on opposite sides of the frame 108.

In a further preferred embodiment, the winding core 105 can be brought into engagement, directly or indirectly, with in each case one connection means 116 which is rotatably mounted on the means for positioning 109.

In a particularly preferred embodiment of the device 101 according to the invention, the device 101 comprises one or two drive means which can or can act on the winding core 105 bidirectionally with a predetermined torque directly or indirectly via at least one of the two connection means 116, such that the material web 103 can be wound off or wound up.

A drive means is for example an electric drive motor.

In a further particularly preferred embodiment of the device 101 according to the invention, the drive means is or can be controlled by a control unit in such a way that the material web 103 can experience a constant tensile stress at least at times, preferably all the time, during winding.

The support means 107 may comprise at least two mutually spaced support surfaces.

A support surface may be formed by an endless belt 113, which is guided over two idle running end rollers 111, which are aligned parallel to the axis of rotation A of the winding core 105.

A support surface may be formed as a continuous support surface.

The endless belt 113 may be at least partially elastic, so that it can at least partially conform under load to the shape of the supported load of the material-laden or material-less winding core 105.

The device 101 may comprise a winding shaft, which is or are formed as one piece or as a separate stub shaft and by means of coupling means, which may comprise the winding shaft, rotatably connected to the winding core 105 or are, wherein the winding shaft or the separate stub shaft with the connection means 116 is engageable or are.

The use of separate stub shafts with respect to a continuous winding shaft is particularly advantageous in winding cores having a relatively large width, since they are manageable.

A coupling means may be formed as an inflatable coupling means.

The end rollers 111 and the means 109 for positioning can be selected so that the material-laden and material-less winding core 105 at any time of settlement of the end rollers 111 spaced apart on the support surface is positioned.

In a preferred embodiment, a pivot arm comprises at its two ends in each case a drive gear 117, 117 ', over which a circumferential chain 115 is guided, wherein a clamping gear 119 is provided which can engage between the gears 117 and 117' in the chain 115 ,

In a preferred embodiment of the invention, at least one end roller 111 can be moved translationally by means of translation in order to be able to retension the bearing surface before or during the winding.

The inventive device (101) is particularly suitable to be assigned to an inkjet printer.

The object of the present invention is therefore also to specify an inkjet printer with the device 101 according to the invention. According to the invention, an inkjet printer is provided, comprising a first device for winding or unwinding a material web 103, a dancer roller, at least one deflecting device and a second device for unwinding or winding the material web 103, characterized in that one of the two devices is used as the one inventive device 101 for Unwinding or winding of the material web 103 is formed by one or on a winding core 105.

In a preferred embodiment, the dancer roller can be translationally movable and designed such that it is acted upon by a preferably constant force against the material web 103, wherein the dancer roller in combination with the one or more drive means is or are controlled by a control unit such that the Material web 103 during winding at least temporarily, preferably all the time can experience a constant tension.

In a further preferred embodiment, the dancer roller can be translationally movable and designed such that it is acted upon by a preferably constant force against the material web (103) in order to taut the material web (103) at least between the dancer roller and the device (101) hold.

Finally, for the sake of order, it should be pointed out that for a better understanding of the structure of the device 101, these or their components have been shown partially unevenly and / or enlarged and / or reduced in size.

Claims (15)

1. Device (101) for unwinding or winding up a material web (103) from or on a winding core (105), wherein the device (101) comprises a supporting device (107) having a supporting surface for the jacket of the cylinder formed by parts of the material web (103) wound on the winding core (105) and the supporting device (107) is designed in such a manner that the supporting surface, due to the weight of the cylinder laid on it, adapts concavely to the cylinder jacket in the region of the support and during rotation of the cylinder a synchronous rotation is possible, wherein the device (101) comprises positioning means (109) engaging in the rotation axis of the winding core (105), which means allow an at least horizontal positioning of the cylinder, wherein the device (101) comprises one or two driving means, characterized in that the winding core (105) can be brought into engagement directly or indirectly with one connecting means (116) mounted rotatably at each of the positioning means (109), wherein a predefined torque can be applied directly or indirectly to the winding core by the one or the two driving means (116) bidirectionally via at least one of the two connecting means (116) in such a way that the material web (103) can be wound up or unwound.
2. Device (101) according to claim 1, characterized in that the positioning means (109) are designed as two swivel arms that are parallel to the rotation axis of the winding core (105), moveable to each other, disposed at a frame (108) and mounted rotatably on opposite sides of the frame (108).
3. Device (101) according to one of the claims 1 or 2, characterized in that the driving means is or are controllable by a control unit in such a way that the material web (103) can experience at least at times, preferably the whole time, a constant tensile stress during the winding.
4. Device (101) according to one of the precedent claims, characterized in that the supporting device (107) comprises at least two supporting surfaces spaced from each other.
5. Device (101) according to one of the precedent claims, characterized in that the one supporting surface is formed by an endless belt (113) which is guided over two end rollers (111) running without load that are aligned parallel to the rotation axis A of the winding core (105).
6. Device (101) according to one of the precedent claims, characterized in that the one supporting surface is designed as a continuous supporting surface.
7. Device (101) according to one of the claims 5 or 6, characterized in that the endless belt (113) is at least partially elastic so that said belt, under load, can adapt at least partially to the form of the supported weight of the winding core (105) loaded with material or not loaded with material.
8. Device (101) according to one of the precedent claims, characterized in that the device (101) comprises a winding shaft that is or are designed in one piece or as separated shaft stubs and said shaft or stubs can be connected, by means of coupling means the winding shaft can comprise, to the winding core in a non-rotatable manner, wherein the winding shaft or the separated shaft stubs can be brought into engagement with the connecting means (116).
9. Device (101) according to one of the precedent claims, characterized in that the coupling means are designed as inflatable coupling means.
10. Device (101) according to one of the claims 5 to 9, characterized in that the end rollers (111) as well as the positioning means (109) are chosen in such a manner that the winding core (105) loaded with material or unloaded can be positioned on the supporting surface at a distance from the end rollers (111) at any time of the unwinding.
11. Device (101) according to one of the precedent claims, characterized in that a swivel arm comprises at each of its both ends one driving toothed wheel (117, 117') over which a surrounding chain (115) is guided, wherein a tensioning toothed wheel (119) is provided which can engage between the toothed wheels (117 and 117') into the chain (115).
12. Device (101) according to claim 5 and one of the preceding claims characterized in that at least one end roller (111) can be moved translationally by means of translational means so that the supporting surface can be re-stressed before or during the winding.
13. Inkjet printer comprising a first device for winding up or unwinding a material web (103), a dancer roller, at least one deflecting device and a second device for winding up or unwinding the material web (103) characterized in that one of the two devices is designed as a device (101) for winding up or unwinding the material web (103) from or on a winding core (105) according to one of the claims 1 to 12.
14. Inkjet printer according to claim 13 characterized in that the dancer roller is movable translationally and designed in such a way that a preferably constant force is applied to it against the material web (103), wherein the dancer roller, in combination with the one or the two driving means, is controllable by a control unit in such a way that the material web (103) can experience at least at times, preferably the whole time, a constant tensile stress during the winding.
15. Inkjet printer according to claim 13 characterized in that the dancer roller is moveable translationally and designed in such a way that a preferably constant force is applied to it against the material web (103) to keep the material web (103) taut at least between the dancer roller and the device (101).

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