Winder for winding a web of material

Description

[0001] The invention relates to a winder for winding a material web.

[0002] Winding the film web is a particularly complex process step in the production of plastic films, as plastic films are produced in a wide variety of ways with very different properties. This influences the winding behavior in many different ways, so a suitable winder must be flexibly adaptable to the behavior of the material web to be wound.

[0003] Typical processing speeds in the production of plastic films range from 2 to 1000 m / min, while the finished rolls typically have a diameter of 50 to 2000 mm and a width of 10 to 6000 mm. The thickness of the plastic films can range from a few micrometers to millimeters. The formulation of plastic films is based on polyolefins (such as PE (polyethylene) or PP (polypropylene)) and ranges from monoextruded films consisting of a single layer to coextruded multilayer films with three, five, or more layers.

[0004] Depending on the production technology, a distinction must also be made between flat and tubular film webs. Flat film webs are produced by cast film extrusion, while tubular film webs must be processed by blown film extrusion.

[0005] Finally, the finished roll to be produced is subject to further processing requirements. Depending on the requirements, either large raw rolls, so-called master rolls, are produced, or the film web is cut directly into several individual rolls in the winder, which are then wound into narrower finished rolls, so-called blanks.

[0006] Various core types (laminated paper, plastic, steel) are used as winding cores. For special applications, coreless winding is also used on a steel shaft, which can then be removed after the winding process. The finished rolls are usually removed from the winder without interrupting the film production process using special roll-changing systems. The finished rolls are then delivered to end users (e.g., for use as packaging material) or are fed into further processing, e.g., coating and stretching systems or printing presses.

[0007] A winder for winding a material web typically consists of a feed station for conveying the material web into the winder, a winding station for producing a finished roll from the material web conveyed by the feed station, and a transfer station where the finished roll can be removed from the winder for further processing. The processes in the feed station, the winding station, and the transfer station are controlled by one or more control units.

[0008] In the winding process used in the winding station, the film web is regularly guided over a deflection roller and then wound onto a film reel. Regarding the interaction between the deflection roller and the film reel, a distinction must be made between the following three processes: Contact winding, central winding and contact central winding.

[0009] With contact winding, only the deflection roller is driven, which acts as a contact roller and is pressed against the film roll. The contact pressure must be selected such that the film roll is rotated while simultaneously preventing slippage. Furthermore, the contact pressure also influences the hardness of the film roll. Contact winding is therefore a simple process for insensitive films.

[0010] In contrast to contact winding, with central winding, the film roll is driven. The deflection roller is usually not positioned against the film roll, but rather is operated at a distance from the film roll with a defined winding gap. This is why it is also referred to as "gap winding." Central winding is particularly suitable for sensitive and soft films for which contact winding is not an option.

[0011] Contact central winding is a combination of contact winding and central winding, so that both the deflection roller and the film roll are now driven. This process allows for a wide variety of film types to be accommodated by adjusting the web tension and contact forces. Winding with a defined winding gap or applying a contact force controlled within narrow limits is also possible. Contact central winding thus allows a winder to be operated with maximum flexibility.

[0012] Another important machine parameter in the winding station is the bearing arrangement of the film roll relative to the machine frame. The following four machine concepts can be distinguished: Carrier rail winder Swing arm winder Turret winder Rotary arm winder

[0013] In the carrier rail winder, the center of the film roll shifts along a horizontal guide rail as the roll diameter increases. Carrier rail winders often use the contact winding method, although, depending on the machine configuration, central winding or contact central winding can also be used. The carrier rail winder is based on a simple principle and is therefore widely used as a winder.

[0014] In the swivel-arm winder, the film roll is held in a frame-mounted rotating arm, which pivots away from the contact roller as the roll diameter increases. With appropriate machine design, the roll weight can be used to generate the contact pressure in contact winding mode. Furthermore, the contact roller can be mounted horizontally to allow for finely adjustable contact pressures. A second drive also enables central contact winding. After winding is complete, the rotating arm is used to transfer the finished roll from the winding station to the transfer station.

[0015] In a turret winder, two winding shafts are arranged on a rotating turning disc. Once the desired roll diameter has been reached, the turning disc pivots 180° during the winding process and brings an empty winding core into the starting position. The film web is automatically severed, and the beginning of the film web is wound onto the new core. The finished roll is removed from the pivoted winding position. Turret winders typically operate using the central winding method. In addition to winders with two winding positions on the turning disc, turret winders with up to four winding positions are also used for fast-running applications (e.g., short stretch film rolls).

[0016] In a rotary arm winder, one winding shaft is mounted on a circular turning disc. A second winding shaft is held in a rotating arm that can be pivoted independently of the turning disc. In this way, rotary arm winders can reduce the web length changes that occur during the turning process and the inevitable associated process influences.

[0017] When winding a plastic film, all of the above-mentioned parameters influence the quality of the finished roll. Only a high-quality wound roll enables the smooth running of subsequent processing steps such as lamination, printing, or converting. In addition to general parameters such as roll width, weight, outer diameter, core diameter, and running length, important quality criteria include edge straightness, clean edge placement, roundness, balance, and transparency or opacity of the film roll. The assessment of a film roll and any winding defects that occur thus allows conclusions to be drawn about correctly set winding parameters or errors in the winder configuration.

[0018] The evaluation of winding defects is therefore an important element in quality control. In order to be able to handle this type of evaluation efficiently, the finished roll is usually provided with an identifier in the transfer station, which enables clear identification and assignment of the production roll to the production parameters. The identifier is usually applied to a label (e.g. in the form of a barcode), which is then stuck onto the finished roll by the operator in the transfer station. To print the label, a label printer is available to the operator separate from the winder, with the control unit having an electrical interface to the label printer. The required printing parameters can thus be transferred to the label via the electrical interface. This transfer can also take place via an intermediate cloud or a printer server, where the cloud or the server contains the necessary data.The digital roll log is stored in a database on the print server. The identifier on the label then provides a link to the corresponding entry in the database, in which all production parameters for the finished roll in question are recorded.

[0019] In addition to the production parameters, local defects and the corresponding positions on the material web can also be saved in the digital roll log. After the production process is complete, it is then possible, for example, to use a rewinder to locate and remove the defective area of ​​the material web. It is also possible to mark the defective areas on the material web during production and then eject them during subsequent processing.

[0020] The label printers used typically operate as desktop printers based on the thermal transfer principle, the direct thermal principle, or the inkjet principle. All printing principles have in common that regular maintenance work must be performed, such as changing the ink ribbon, adding labels, or changing a label roll. US 10 099 882 B2 and US 2010 / 021651 A1 disclose winding devices that include a label printer. US 2019 / 054677 A1 discloses a chamber vacuum packaging machine that includes a drawer for a label printer.

[0021] The object of the invention is to simplify the performance of the maintenance work required for the label printer.

[0022] This object is achieved by the features of patent claim 1. Further preferred embodiments emerge from the subclaims.

[0023] A key finding of the invention is that the transfer station to the label printer has a mechanical interface. Since the label printer is a purchased product with respect to the winder, the label printer has previously been used as a desktop printer, so a mechanical interface between the transfer station and the label printer was not considered by the expert. However, it has been shown that it is worthwhile to abandon the standard desktop environment in favor of a mechanical interface if the mechanical interface can simultaneously simplify and optimize the operation of the label printer.

[0024] According to a preferred embodiment, the label printer has a barcode printing unit, wherein the said identifier is printed on the label using the barcode. Particularly preferably, the label printer has a QR code printing unit. The QR code (Quick Response) is a two-dimensional code, described, for example, in EP 0 672 994 A1. The QR code consists of a square matrix with black and white squares that represent the encoded data in binary form. A special marking in three of the four corners of the square specifies the orientation. The data in the QR code is enhanced compared to the barcode by an error-correcting code. This tolerates a loss of up to 30% of the code. Other variants are the Micro QR Code, the Secure QR Code (SQRC), the iQR Code, and the Frame QR Code.

[0025] According to a further preferred embodiment, the label printer comprises an RFID printing unit. Radio Frequency Identification (RFID) enables the automatic identification of a finished roll wirelessly using electromagnetic waves. RFID labels can be printed and applied in the same way as barcode labels or QR code labels. The labels then contain an RFID transponder on which data can be stored, modified, and deleted. An RFID reader can read them and optionally rewrite them. The main advantages of RFID labels over barcode labels or QR code labels are the contactless process and the secure and fast data exchange.

[0026] According to a further preferred embodiment, the label printer is provided with a database interface. The database interface allows, for example, the integration into the digital roll protocol described above.

[0027] According to the invention, the mechanical interface comprises a telescopic drawer. This allows the label printer to be placed in an ideal position in the transfer station, allowing the operator to quickly remove the labels and apply them directly to the finished roll. Furthermore, easy and ergonomic maintenance of the label printer is possible, such as refilling label rolls. Finally, the mechanical interface of a telescopic drawer allows for seamless integration of the label printer into the winder, while at the same time providing better protection against external influences (e.g., damage or contamination).

[0028] According to a further preferred embodiment, the mechanical interface comprises a label dispensing stamp for automatically applying printed labels to the finished roll in the transfer station. With such a mechanical interface, the printing and application of labels can be fully automated. Maintenance work for the label printer can be seamlessly integrated into this fully automated process by the control unit prompting the operator to perform maintenance work during appropriate printing breaks. Conversely, the production process of a finished roll can be delayed, paused, or stopped if necessary maintenance work on the label printer is not performed; in this case, the control unit expediently issues a warning signal.

[0029] According to a further preferred embodiment, the material web consists of a plastic film.

[0030] Further details and advantages of the invention are described with reference to the accompanying drawings, in which: Fig. 1 a schematic side view of a double support rail winder of a blown film extrusion line, Fig. 2 a first schematic 3D view of the right support rail winder according to Fig. 1 , Fig. 3 a second schematic 3D view of the right support rail winder according to Fig. 1 , and Fig. 4 a third schematic 3D view of the right support rail winder according to Fig. 1 .

[0031] Fig. 1shows a schematic side view of a double support rail winder of a blown film extrusion line. The upstream blown film extrusion line delivers a film tube 101, which is guided over a web center guide 102 and subsequently passes through a pretreatment 103 to increase the surface tension. The feeder 104 then conveys the film tube to the slitting device 105, where the film tube is slit and divided into two material webs. Further operation then proceeds in principle symmetrically, i.e., the first material web is fed to the left support rail winder 131, and the second material web is fed to the right support rail winder 132.

[0032] According to their basic structure, the support rail winders 131, 132 consist of a feed station 133, 134 for conveying the material web into the winder, a winding station 135, 136 for producing a finished roll from the material web conveyed by the feed station and a transfer station 137, 138 in which the finished roll can be removed from the winder for further processing.

[0033] The feed station 133, 134 contains pendulum rollers 106, 107 that measure the web tension. Using these measured values, the control unit (not shown in detail) calculates the required drive values ​​in the support rail winder 131, 132 to regulate the web tension to a specified target value. The feed station 133, 134 can also contain, for example, longitudinal cutting devices 108, 109, which interact with spreader rollers to divide and finish the material web into several parallel blanks.

[0034] The core of the winding station 135, 136 consists of the deflection roller 112, 113 and the film roll 114, 115. The film roll 114, 115 can be moved along a horizontal guide rail depending on the roll diameter. The winding station 135, 136 is also equipped with functions for automated roll changing. These include cutting systems with pull or strike blades arranged in the deflection roller 112, 113. These sever the continuously fed material web when the finished roll diameter is reached. Using suitable winding mechanisms, the film end created by the cut is automatically wound onto the new winding core. For this purpose, new cores are held in the magazine 110, 111 together with winding shafts and are automatically moved into the winding position during the roll change.

[0035] Finally, the transfer station 137, 138 is responsible for the removal of the finished rolls 116, 117, which often weigh several tons. For this purpose, deposit arms 118, 119 and crane systems 120, 121 are provided. The crane systems 120, 121 also serve to deposit new cores in the magazine 110, 111 for reuse.

[0036] Fig. 2 shows a first schematic 3D view of the right support rail winder 132 according to Fig. 1 . The corresponding reference numerals from Fig. 1 were adopted, so that the description of Fig. 1The two horizontal support rails of the support rail winder 132 are located in the front side part 201 and the rear side part 202, respectively, and extend into the transfer station 138. Also installed in the front side part 201 is the control unit (not shown) with a touchscreen 203 and a keypad 204. The control unit has an electrical interface to a label printer 205, which is installed in the front of the front side part 201. The label printer 205 is preferably a barcode printer. As soon as a finished roll is ready for removal in the transfer station 138, the label printer 205 automatically prints a self-adhesive label, which can then be removed by the operator and applied to the finished roll for identification.

[0037] Fig. 3 shows a second schematic 3D view of the right carrier rail winder 132 according to Fig. 1. The corresponding reference numerals from Fig. 1 and Fig. 2 were adopted, so that the description of Fig. 1 and Fig. 2 A telescopic drawer 301 is provided as a mechanical interface between the transfer station 138 and the label printer 205, so that the label printer can be moved between the retracted position according to Fig. 2 and the extended position according to Fig. 3 In the extended position according to Fig. 3 It is easy for the operator to perform maintenance work, such as changing the ribbon or changing a label roll. The retracted position according to Fig. 2 serves as the operating position. In this position, the label printer 205 is effectively protected from external influences and, at the same time, does not pose a hindrance to the operator.

[0038] Fig. 4shows a third schematic 3D view of the right carrier rail winder 132 according to Fig. 1 . The corresponding reference numerals from Fig. 1 , Fig. 2 and Fig. 3 were adopted, so that the description of Fig. 1 , Fig. 2 and Fig. 3 In addition to the label printer 205, the right-hand carrier rail winder 132 now also has a label printing dispenser 401. The label printing dispenser 401 can be provided in addition to or as an alternative to the label printer 205. Preferably, the label printing dispenser 401 is an RFID printer for automatically applying RFID labels.

[0039] The label printing dispenser 401 consists of its own control unit 402, the actual printing unit 403, and the sending pad 404, allowing the label printing dispenser 401 to operate fully automatically. As soon as a finished roll is ready for removal at the transfer station 138, the printing unit 403 prints a label, which is then automatically applied to the finished roll by the sending pad 404 for identification. The labels are applied automatically by compressed air from the sending pad 404 using a tamp-blow applicator. The label is dispensed over a short distance by a blast of air or by direct contact of the spring-loaded dispensing plate with the surface of the finished roll. The variable dispensing stroke of the sending pad 404 also enables the automatic labeling of finished rolls with different diameters.In addition, the 404 sending stamp is equipped with a reading unit that can be used to monitor whether the label is in the correct and readable position on the surface of the finished roll after it has been applied. List of reference symbols 101 film tube 102 Track center control 103 Pretreatment 104 Preference 105 Longitudinal cutting device 106 pendulum roller 107 pendulum roller 108 Longitudinal cutting device 109 Longitudinal cutting device 110 magazine 111 magazine 112 Deflection roller 113 Deflection roller 114 film roll 115 film roll 116 Finished rolls 117 Finished rolls 118 Storage arms 119 Storage arms 131 Carrier rail winder 132 Carrier rail winder 133 Feed station 134 Feed station 135 Changing station 136 Changing station 138 transfer station 201 Front side panel 202 Rear side panel 203 touch screen 204 keypad 205 label printer 401 Label printing dispenser 402 Control unit 403 pressure unit 404 Sending stamp

Claims

1. Winder for winding a material web, with a feed station for conveying the material web into the winder, comprising a winding station for producing a finished roll from the material web conveyed by the feed station, with a transfer station, in which the finished roll can be removed from the winder for further processing, with a controller for controlling the feed station, the winding station and the transfer station, wherein the controller has an electric interface for a label printer, and wherein the transfer station has a mechanical interface for the label printer, characterized in that the mechanical interface has a telescopic drawer such that the label printer can be moved between a retracted position and an extended position, in which the operator can perform maintenance work, wherein the retracted position is used as the operating position.

2. Winder according to claim 1, wherein the label printer has a barcode printing unit.

3. Winder according to any one of claims 1 - 2, wherein the label printer has an RFID printing unit.

4. Winder according to any one of claims 1 - 3, wherein the label printer has a database interface.

5. Winder according to any one of claims 1 - 4, wherein the mechanical interface has a label applicator pad for automatically applying printed labels to the finished roll in the transfer station.

6. Winder according to any one of claims 1 - 5, wherein the material web consists of a plastic film.