Abstract:
A winding device for winding up a web-like material has a roll core, on which the web-like material is wound up into a material roll, and a web guiding roller, which guides the web-like material before or when the web-like material reaches the roll core or the material roll, and a pressing element, which presses the web-like material onto the roll core or the roll after the web-like material already rests on the roll core or the roll. The pressing element is movable in relation to the roll core, and is mounted at both ends in lever arms forming a lever arm pair. The lever arms are mounted so as to be rotatable, and so that the pressing element is pivotable around bearing points of the lever arms.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     This is a national stage of PCT/EP07/060,692 filed Oct. 9, 2007 and published in German, which has a priority of German no. 10 2006 047 995.5 filed Oct. 9, 2006, hereby incorporated by reference. 
     BACKGROUND OF THE INVENTION 
     1. Field of Invention 
     The invention relates to a winding device for winding up a web-like material as described herein. 
     2. Description of the Prior Art 
     Web-like material, such as plastic film, which is produced in a web production device, such as an extrusion device, is frequently not processed further directly, i.e., “in-line”, but rather first wound up into rolls using a so-called winding device. These rolls are first supplied to a further processing machine. Such further processing machines include printing presses, bag production machines, and many other machines. 
     Other materials, such as paper, are also wound up in a winding device and supplied to a further processing machine in the form of rolls. 
     These rolls are frequently formed in that the web-like material is wound onto a roll core. Before the web-like material reaches this roll core and/or the roll, on which web-like material is already wound, it is guided over a web guiding roller. This web guiding roller may be situated at a small distance to the roll core or to the roll (so-called “gap winder”) or may press the web-like material directly onto the roll core or the roll. In the latter case, the winding device is referred to as a contact winder. In both cases, the cited web guiding roller is typically the last roller over which the web-like material is guided before or when it reaches the roll core or the roll. 
     To prevent an air inclusion between the roll core or the roll and the new layer of the web-like material, a pressing element is frequently assigned to the roll, which may be positioned against the roll. This pressing element is typically designed as a pressing roller. 
     In known winding devices, the mechanism which is used for positioning the pressing elements on the roll, comprises carriages, in which the pressing roller or the pressing element is mounted on both ends, the carriages being situated so they are displaceable on two rails running parallel to one another. These rails are fastened to walls which also support the roll core. The carriages on which the pressing rollers are mounted are moved in the direction toward or away from the roll core using suitable actuators, such as a piston-cylinder unit. 
     This way of positioning the pressing roller on the roll core has the disadvantage of the large space requirement caused by a linear guide of the carriages. 
     The object of the present invention is to propose a winding device, in which the mechanism which is used for positioning the pressing element on the roll requires less space. 
     The object is achieved by a winding device as described herein. 
     SUMMARY OF THE INVENTION 
     Accordingly, the pressing element is mounted on both ends in lever arms, which form a lever arm pair. This pressing element may be a pressing roller, which is mounted so it is rotatable in this lever arm pair. The lever arms are mounted so they are rotatable in the walls, in which the roll core is also mounted. Because the bearing points of the pressing element in the lever arms and the bearing points of the lever arms in the walls are not coincident, the pressing element is finally pivotable around the bearing points of the lever arms. 
     In this way, rails are no longer necessary for the movement of the pressing element, but rather only lever arms, which are mounted so they are rotatable in one point. For this reason, the winding device according to the invention may be constructed significantly more compactly than a winding device according to the known prior art. 
     The question of the space requirement in so-called turret winders is of decisive significance. In this type of winding device, the roll core and the mechanism for positioning the pressing element are fastened on discs or plates, which are mounted so they are rotatable in the machine framework. At least one second roll core and at least one further mechanism for positioning pressing elements are mounted and/or fixed on each of these discs or plates. A turret winder is used, after a roll has been completely wound, for the rapid winding onto the second roll core of the new web beginning formed by a cut. An especially advantageous embodiment of a winding device according to the invention therefore comprises the cited features of a turret winder. Particularly in this case, the space requirement of the mechanism for positioning the pressing element directly influences the size of the discs and/or plates and also the drive power which is necessary for their rotation in the machine framework. 
     In an advantageous refinement of the invention, the pivot range of the lever arms is dimensioned in such a way that a pressing roller may come into contact with two roll cores alternately. In this way, the pressing roller, which does not have its own rotational drive, may be set into rotation by a rotating roll core. The pressing roller may thus be accelerated before it contacts the roll. An acceleration of the pressing roller by the roll on which web-like material has already been wound may result in damage to the web-like material. 
     Drive means are advantageously assigned to the roll cores, which apply a torque to the roll cores. A separate drive may be assigned to each roll core. Alternatively, two or more roll cores may be driven by one drive, a detachable coupling being provided between the drivetrain and the roll core to be able to stop the roll for the purpose of removal, while a further roll core is wound further. 
     In addition, the object of the invention is a method for the continuous winding of a web-like material into rolls as described herein. Further method steps which are part of the method according to the invention are described hereafter in the context of the description of the object. 
     Further exemplary embodiments of the invention are disclosed in the description of the object and the claims. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       In the figures: 
         FIG. 1  shows a schematic side view of a winding device according to the prior art, 
         FIG. 2  shows a schematic side view of a winding device according to the invention during the winding operation, 
         FIG. 3  shows a schematic side view of a winding device according to the invention during the roll core change, 
         FIG. 4  shows a schematic side view of a winding device according to the invention having deflection pulleys during the winding operation, 
         FIG. 5  shows a schematic side view of a winding device according to the invention having deflection pulleys during the preparation for the roll core change, 
         FIG. 6  shows a schematic side view of a winding device according to the invention having deflection pulleys during the roll core change, 
         FIG. 7  shows a schematic side view of a winding device according to the invention having deflection pulleys during the roll core change, 
         FIG. 8  shows a schematic side view of a winding device according to the invention having deflection pulleys after the roll core change. 
         FIG. 9  shows section IX-IX indicated in  FIG. 3 . 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     Further scope of applicability of the present invention will become apparent from the detailed description given hereinafter. However, it should be understood that the detailed description and specific examples, while indicating preferred embodiments of the invention, are given by way of illustration only, since various changes and modifications within the spirit and scope of the invention will become apparent to those skilled in the art from this detailed description. 
       FIG. 1  shows a winding device according to the prior art. In this case, the web-like material  2 , which is supplied to the winding device in the run direction A, is guided via the contact roller  3 . The contact roller  3  is positioned on the roll  4 , which is wound on a roll core  5 , so that the web-like material guided by the contact roller  3  is laid on the roll. A pressing roller is positioned on the roll  4  in the transport direction of the material behind the contact roller, which presses the uppermost layer of the web-like material  2  with pressure against the roll  4 , in order to prevent air inclusions. The so-called roll hardness may be established by the strength of the pressing. 
     The roll core  5  is mounted so it is rotatable on both ends in discs, of which only the rear disc  7  is shown. The discs are in turn mounted so they are rotatable in the machine framework (not shown). The contact roller  3  is also mounted on the machine framework via elements which allow a movement of the contact roller  3  in relation to the roll core  5 . 
     The pressing roller  6  is mounted via displacement carriages (not shown) in guides  8 , the guides being fastened on the rails. The pressing roller  6  may be displaced in relation to the guides and thus in relation to the roll core  5  with the aid of piston-cylinder units or other suitable drives. 
     A second roll core  9  and further guides  10  are also mounted and/or fastened in the cited discs. The guides  10  also support a second pressing roller  11 , which is assigned to the roll core  9 , via these displaceable carriages. 
     By rotating the discs  7 , the roll core  9  may be pivoted in the direction toward the contact roller, so that this roll core  9  comes into contact with the web-like material. The roll  4  is pivoted away from the contact roller  3  by the rotation of the discs. The web-like material may now be cut through by a cutting device (not shown), 
     so that a new web beginning results, which may be fixed on the roll core  9  by suitable means. The old roll  4  may now be removed from the winding device and replaced by an empty roll core. In this way, a new roll results without the winding device having to be stopped for the purpose of changing the roll core. 
       FIG. 2  shows a winding device  1  according to the invention during the winding operation. The identical elements to the winding device shown in  FIG. 1  are provided with the same reference numerals in  FIG. 2 . In contrast to the winding device according to the prior art, in the device according to the invention, the pressing roller  6  is mounted in a lever arm pair, of which only the rear lever arm  12  is shown. Both lever arms of the lever arm pair are connected to one another via suitable coupling elements, such as connecting rods, so that the rotational axis of the pressing roller always runs parallel to the rotational axis of the roll core. 
     In an advantageous embodiment, a gear ring or gear ring segment is fastened for this purpose on each disc  7 , on which gear wheels fastened to a coupling shaft roll. Further gear wheels may be provided between gear ring or gear ring segment and gear wheels of the coupling shaft. The coupling shaft may be guided through an axial hole of the pressing roller  6 ,  11 . If a torque is applied to one of the two lever arms, the coupling shaft rotates and transmits a torque to the particular other lever arm, the end of the coupling shaft which is mounted so it is rotatable in the other lever arm also rolling on a gear ring or gear ring segment. In this way, an exactly equal angle of the lever arms is ensured. This state of affairs is explained hereafter on the basis of  FIG. 9 . 
     The lever arm  12  is mounted via a bearing  13  in the disc  7 . The rotational axis of the pressing roller  6  is parallel to the rotational axis of the bearing  13 . However, both axes are not aligned. This is also true for all other 
     lever arms which are shown in these and the following figures, but also for the lever arms which are not shown. 
     The pivoting of the lever arm is performed, for example, by a drive motor onto whose rotor axis a pinion is plugged and fastened. This pinion engages with a gear wheel or gear wheel segment, which is fastened on a lever arm and whose rotational axis is aligned with the rotational axis of the bearing  13 . An air motor, which is very compact and light, is preferred as the drive motor. This is discussed in still greater detail hereafter in the context of the description of  FIG. 9 . 
     The pressing roller  11 , which is mounted and driven in the lever arm  14  similarly to the pressing roller  6  mounted in the lever arm  12 , is shown in a position pivoted away from the roll core  9  in the operating situation shown in  FIG. 2 . 
       FIG. 3  shows the winding device  1  according to the invention already shown in  FIG. 2 , after the discs have been rotated far enough that the roll core  9  assumes the original position of the roll core  5 . The web-like material  2  is first wound further onto the roll in the situation shown, the web-like material  2  also running over the pressing roller  11 . 
     After the operating situation shown has been achieved, the web-like material is cut through by a cutting device (not shown). The web end thus resulting is wound further onto the roll  4 . The web beginning resulting due to the cutting of the web-like material is fixed on the roll core  9  by a suitable measure, such as fixing by an adhesive. The web-like material  2  is now wound onto the roll core  9 . In the meantime, the resulting web end has reached the old roll  4 , so that the pressing roller  11  is no longer in contact with the web-like material  2 . As soon as the new web beginning has been fixed on the roll core, the lever arm  14  is pivoted in the direction toward this roll core and the pressing roller  11  is thus positioned 
     on the roll core. After the replacement of the roll  4  by a new roll core, the changing procedure is completed and the operating situation shown in  FIG. 2  is reproduced. 
     It is to be emphasized that the winding device shown in  FIGS. 2 and 3  is used in particular with slowly running web-like material. The reason for this may be seen in that the pressing roller  11 , which is at rest or even rotates opposite to the web direction from the prior winding on the roll core  9  in the position shown in  FIG. 2 , must be set into rotation and/or into opposing rotation by the web-like material as soon as they come into contact. A high transport velocity of the material  2  would also make a high acceleration of the pressing roller necessary, however, and would thus require a large force. The forces acting in this case may result in damage of the web-like material, however. The limit at which the described device may still be used without damaging the web-like material is a transport velocity of 150-200 m/minute, this limit also being able to be a function of the material properties. 
     A winding device which is also suitable for winding up rapidly running material is shown in  FIGS. 4 through 8 . 
       FIG. 4  schematically shows a further embodiment of the winding device  1  according to the invention. This winding device essentially corresponds to the winding device shown in  FIG. 2 , but the device shown in  FIG. 4  additionally comprises deflection pulleys  15  and  16 . These deflection pulleys  15  and  16  are mounted so they are rotatable in holders which are fastened on the discs. The number of the deflection pulleys is not restricted to two, multiple deflection pulleys may be provided. Only the holders  17  fastened on the rear disc are shown in  FIG. 4 . The function of the deflection pulleys  15 ,  16  will become clear on the basis of the following description of  FIGS. 5 through 8 , in which the roll core changing procedure is illustrated. 
       FIG. 5  shows the winding device  1 , in which the lever arm  14  has been pivoted in the direction toward the roll core  9 , so that the pressing roller  11  is frictionally engaged with the roll core  9 . The roll core  9  is set into rotation by a drive, by which the pressing roller  11  is also set into rotation. The rotational velocity is selected so that the peripheral velocity of the pressing roller  11  essentially corresponds to the transport velocity of the web-like material. 
     In  FIG. 6 , in comparison to  FIG. 5 , the contact roller  3  is first displaced in relation to the disc  7  so that it is no longer in contact with the roll  4 . The discs are subsequently rotated by an angle of approximately 90°. At this rotational angle, the deflection pulley  15  nearly comes into contact with the web-like material  2 . The deflection pulley  15  may have an external pre-accelerator as a function of the material. However, it may also be set into rotation by the web-like material. The deflection pulley has a small diameter and is manufactured from a light material, so that only a small torque must be applied for its acceleration in comparison to the acceleration of a pressing roller. The deflection pulleys may therefore be used in spite of high transport velocities of the web-like material. During the further rotation of the discs, the lever arm  14  is pivoted until it runs approximately parallel to the holder  17 . The pivoting is performed chronologically so that the pressing roller  11  does not touch the web-like material  2  as much as possible. The rotary impulse of the non-driven pressing roller  11  is maintained or decreases only slightly. The rotation of the disc occurs further until the new roll core  9  has come into contact with the web-like material  2 . This situation is shown in  FIG. 7 . 
       FIG. 8  shows the operating situation, according to which the web-like material  2  has been cut through using a cutting device. The resulting web end has been wound onto the roll  4 . The newly resulting web beginning has again been fixed on the new roll core  9 , so that 
     a new roll arises at this point. The lever arm  14  has been pivoted in the direction toward the roll core  9  and in this way the pressing roller has been pressed against the roll core  9  and/or the new roll. 
       FIG. 9  shows section IX-IX indicated in  FIG. 3 . Both discs  7  may be seen in this view, in which both lever arms  14  are rotatable around the rotational axis  20 , symbolized as a dot-dash line. A gear ring or a gear ring segment  21  is fastened on each disc  7 . One gear wheel  22  engages with each of these gear rings or gear ring segments  21 , both gear wheels being connected rotationally fixed to a coupling shaft  23 . The coupling shaft  23  is mounted so it is rotatable in the lever arms  14  via suitable bearings  24 , such as ball bearings. 
     If the lever arms  14  are pivoted in relation to the discs  7 , because of the described construction, both lever arms always assume the same pivot angle. 
     The pressing roller  11  is itself mounted so it is rotatable on the coupling shaft  23  using swivel bearings  25 . As already described, the pressing roller is not driven. It is thus mounted so it is freely rotatable. 
     To be able to move the lever arms  14  in relation to the discs  7 , gear wheels or gear wheel segments  26  are attached to the lever arms  14 . Pinions  27 , which are attached rotationally fixed to the drive shafts  29  of drive motors  28 , engage with these gear wheels or gear wheel segments  26 . These drive motors, which are advantageously implemented as air motors, are fastened to the discs  7 . 
     The invention being thus described, it will be apparent that the same may be varied in many ways. Such variation are not to be regarded as a departure from the spirit and scope of the invention, and all such modifications as would be recognized by one skilled in the art are intended to be included within the scope of the following claims. 
     
       
         
               
             
               
               
             
           
               
                   
               
               
                 List of reference numerals 
               
               
                   
               
             
             
               
                   
               
             
          
           
               
                 1 
                 winding device 
               
               
                 2 
                 web-like material 
               
               
                 3 
                 contact roller 
               
               
                 4 
                 roll 
               
               
                 5 
                 roll core 
               
               
                 6 
                 pressing roller 
               
               
                 7 
                 rear disc 
               
               
                 8 
                 guide 
               
               
                 9 
                 roll core 
               
               
                 10 
                 further guide 
               
               
                 11 
                 pressing roller 
               
               
                 12 
                 lever arm 
               
               
                 13 
                 Bearing 
               
               
                 14 
                 lever arm 
               
               
                 15 
                 deflection pulley 
               
               
                 16 
                 deflection pulley 
               
               
                 17 
                 holder 
               
               
                 18 
               
               
                 19 
               
               
                 20 
                 rotational axis 
               
               
                 21 
                 gear ring or gear ring segment 
               
               
                 22 
                 gear wheel 
               
               
                 23 
                 coupling shaft 
               
               
                 24 
                 bearing 
               
               
                 25 
                 swivel bearing 
               
               
                 26 
                 gear wheel or gear wheel segment 
               
               
                 27 
                 pinion 
               
               
                 28 
                 drive motor 
               
               
                 29 
                 Driveshaft 
               
               
                 A 
                 running direction of the web-like material of the winding device 
               
               
                 B 
                 rotational direction of the disc 7