Abstract:
The invention relates to a winding machine for winding material webs, in particular foils or films, wherein the winding machine comprises a feeder system with a first belt feeder which, during the winding of the material web around a winding core in a first direction, wraps itself at least partially around the material web. The feeder system comprises a second belt feeder which is suitable for winding the material web in a second direction around the winding core.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application is a U.S. National Stage of International Patent Application No. PCT/EP2015/002194, filed Oct. 31, 2015, designating the United States and claiming benefit of German Patent Application No. 10 2014 117 522.0, filed Nov. 28, 2014. 
     
    
     BACKGROUND OF THE INVENTION 
       [0002]    The invention relates to a winding machine for winding material webs, in particular foils or films, having a feeding system comprising a first belt feeder which, during the winding of the material web around a winding core, wraps itself in one direction at least partially around the material web. 
         [0003]    For the winding of material webs, winding machines are provided with one or several contact rolls which rest on the material web and press the air out during the winding operation. With extremely thin foils, which are especially elastic, a different tension can build up over the width of the material web as a result of a non-uniform thickness profile during the production, caused by temperature fluctuations. Contact rolls are not suitable for use with these thin foils since they are extremely inflexible and exert the same pressure over the complete winding width onto the foil. 
         [0004]    To support the winding operation with thin foils, feeder systems are known which press with a plurality of side-by-side arranged belts onto the foil. To be sure, these belts are driven by a joint drive, but are flexible enough, so that they can exert a differing pressure onto the thin foils over the winding width of the material web. Tensions caused by differences in the thickness profile do not increase in this way. These feeder systems, however, have the disadvantage of being configured only for one winding direction. A further disadvantage is the limited flexibility for different winding diameters. 
       SUMMARY OF THE INVENTION 
       [0005]    It is the object of the invention to create a winding machine provided with a feeder system which is suitable for the winding in two directions and for different winding diameters. 
         [0006]    The above and other objects are achieved according to an embodiment of the invention by the provision of a winding machine with a feeder system for winding a material web of foil or film around a winding core, comprising: at least one circulating belt; a first belt feeder constructed and arranged to wrap the at least one circulating belt at least partially around the material web during a winding of the material web around the winding core in a first direction; and a second belt feeder constructed and arranged to wind the material web in a second direction around the winding core. 
         [0007]    Thus, the invention involves a winding machine that comprises for the winding of material webs, in particular foils, a feeder system with a first belt feeder which at least partially wraps itself around the material web during the winding of the web around a winding core in a first direction. 
         [0008]    According to an embodiment of the invention, a feeder system is provided that comprises a second belt feeder which is suitable for winding the material web in a second direction around the winding core. As a result, it is possible to determine very quickly and without having to take retrofitting measures, e.g. for coated material webs, on which side the coating should come to rest during the winding operation. 
         [0009]    The first direction for the wrapping around can be in clockwise direction, for example, so that the second direction in which the material web is wrapped by the second belt feeder can be counter-clockwise, and vice versa. 
         [0010]    The first and the second belt feeder preferably can respectively comprise at least two levers, between which a circulating belt is arranged. Both belt feeders thus can admit the material web with a flexible tension over the width. It is furthermore possible to wind strips of material webs in both winding directions. 
         [0011]    According to a further embodiment, the circulating belt is an endless belt which circulates between respectively two levers of the first and the second belt feeder. Even though only a single belt feeder is engaged each time, the second belt feeder which is in the rest position, ensures a maximum angle of the wrapping of the belt around the material web because of the belt guidance. 
         [0012]    The levers are preferably embodied as two-sided, centrally positioned levers, thus making it possible to wind up a large, variable diameter range. 
         [0013]    In one embodiment, the levers are positioned with the aid of two coupling links, which allows determining a precise pivoting range for the lever. The pivoting range becomes smaller as a result of the second coupling link, resulting in a very compact belt feeder. 
         [0014]    A combination of both lever systems, wherein the first belt feeder is provided with two-sided, centrally positioned levers, and the second belt feeder is provided with levers positioned via two coupling links, allows realizing at least in one winding direction a large winding range with a variable diameter while, at the same time, the feeder system of the winding machine does not require too much space. 
         [0015]    Via the pressure elements, arranged in the region of the lever heads, additional pressure can be exerted onto the material web to be wound up. The pressure element can be embodied as force-loaded or spring-loaded elements. In an embodiment, the pressure elements are embodied as spring plates which can enlarge in the manner of a finger the wrap-around area of the feeder system where pressure is applied. 
         [0016]    With the aid of the pivotable arrangement of the feeder system on the winding machine, a position protecting the material web can be assumed for exchanging and/or newly inserting the winding core. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0017]    The invention is explained in further detail with the aid of the enclosed drawings, which show in: 
           [0018]      FIG. 1  is a perspective view of a winding machine; 
           [0019]      FIG. 2  is a section through the winding machine, in a view from the side; 
           [0020]      FIG. 3  is a representation of a detail of the feeder system; 
           [0021]      FIG. 4  is an enlarged detail of the view in  FIG. 1 ; 
           [0022]      FIG. 5  is a further representation of a detail of the feeder system. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0023]    According to  FIGS. 1 and 2 , a material web  2 , for example a plastic foil or film, enters the winding machine  1  and initially moves around a traction mechanism, which consists of a tilt-mounted and pneumatically charged clamping roll  3  with a lower roll  4  that exerts a constant tension onto the material web  2 . The material web  2  is furthermore guided between two guide rolls  5 ,  6  provided with a length-measuring device, not shown herein, for determining the length of the material web  2  that enters the winder  1 . The material web  2  is furthermore moved to a cross cutter  10  where the material web  2  is clamped between two rolls  11 ,  12  and is conveyed to the feeder system  20  where it can be wound around a winding core  25  or a winding sleeve. The cross cutter  10  is pivotally hinged to the frame  7  of the winding machine  1  and comprises a cutting device which cuts the material web  2  transverse to the longitudinal direction and/or the transporting direction. The rolls  12 ,  13  which are designed to generate pressure that is exerted onto the material web  2 , are positioned pivotally hinged on a lever system to make space for inserting the material web  2 . The roll  11  advantageously can be designed as a driven roll. 
         [0024]    The feeder system  20  comprises at least two support plates  23 ,  23 ′ which are connected to several shafts and/or axes. Shown for this exemplary embodiment are three support plates  23 ,  23 ′,  23 ″, which are arranged on the frame  7  of the winding machine  1 , to pivot around a pivoting point  21  with the aid of at least one adjustment means  22 , for example a pneumatic cylinder or an eccentric drive. The support plates  23 ,  23 ′,  23 ″ are provided with an opening  24  for accommodating a winding core  25  which can be driven outside of the winding machine  1 . 
         [0025]    A first and a second belt feeder  30 ,  40  are arranged on both sides of the opening  24  and/or parallel to the longitudinal axis of the winding core  25 . 
         [0026]    The first belt feeder  30  shown in  FIG. 3  comprises at least two levers  31 ,  31 ′ (see  FIG. 4 ) of which only the lever  31  is visible in  FIG. 3 . The levers  31 ,  31 ′ of the first belt feeder  30  are embodied as two-sided levers, wherein a head  34  with a pressure element  38  in the form of a spring plate is arranged on one lever end and an adjustment means  33  in the form of a pneumatic cylinder engages on the other end. The pressure element  38  can also be arranged between two levers  31 ′,  31 ″. Each lever  31 ,  31 ′ is positioned pivoting via a pivoting point  32 , so that when the adjustment means  33  is actuated, the heads  34  of the levers  31 ,  31 ′ carry out a pivoting movement. A deflection roll  35  is furthermore installed at the head  34  of each lever  31  and an additional roll  36  is arranged in the area of the pivoting point  32 , the axis of which connects the two levers  31 ,  31 ′. Respectively one deflection roll  35  and one roll  36  are thus arranged between two levers  31 ,  31 ′ and deflect a belt  37 . The first belt feeder  30  thus comprises at least two levers  31 ,  31 ′ between which a belt  37  is arranged. The levers  31 ,  31 ′ can be pivoted via the adjustment means  33  with the head  34  toward the intake opening  24  that holds the winding core  25 , wherein the levers  31 ,  31 ′ have a concave recess on one side to create space for the winding of the material web  2  with increasing diameter. 
         [0027]    The second belt feeder  40  also comprises at least two levers  41 ,  41 ′ between which the belt  37  is arranged. Each lever  41 ,  41 ′ is provided on one end with a head  44  and a pressure element  38 , also taking the form of a spring plate in this case. The pressure element  38  can also be arranged between two levers  41 ′,  41 ″. A deflection roll  45  is furthermore arranged on each head  44  which connects two levers  41 ,  41 ′ and functions to deflect the belt  37 . An adjustment means  43  in the form of a pneumatic cylinder is arranged at the other end of each lever  41 ,  41 ′ which can pivot the lever  41  around a pivoting point  42 . A roll  46  is furthermore arranged at the pivoting point  42 , the axis of which connects the two levers  41 ,  41 ′, across which the belt  37  is guided. For this exemplary embodiment, the lever is also embodied as a two-sided lever which can, however, be pivoted around two spaced-apart coupling joints in the form of a four-bar linkage, so that the head  44  of the lever  41  realizes a defined pivoting movement which will be explained later on. 
         [0028]    The belt  37  moves through the first and second belt feeder  30 ,  40  and, in the process, is guided via the deflection rolls  35  and  45  to the rolls  36  and  46 . From there, the belt  37 , which is embodied as endless belt and/or as a flat belt, moves to a drive roll  26  and a belt tensioner  27 . The drive roll  26  optionally drives the belt in one direction or the other, depending on the feeding direction for the material web  2 . The belt tensioner  27  ensures a sufficient tension between a parked position and a winding position for the feeder system  20 .  FIG. 3  shows the feeder system  20  and the course of the belt  37  around the inserted winding core  25 . Starting from the deflection rolls  45  and  35 , the belt  37  in this case wraps itself at least partially also around the winding core  25 . With a removed winding core  25 , the belt  37  connects the deflection rolls  45  and  35  over the shortest distance (dashed line). 
         [0029]    Even if only one or two levers  31 ,  31 ′ and/or  41 ,  41 ′ are mentioned in the three preceding paragraphs,  FIGS. 1 and 4  clearly show that the feeder system  20  with the first and the second belt feeder  30 ,  40  comprises a plurality of levers  31 ,  31 ′,  31 ″,  41 ,  41 ′,  41 ″ with belts  37  arranged in-between. The number of levers and belts depends on the width of the web material for winding, which can measure up to 3 m. A further aspect of configuring the feeder system  20  with the number of levers and belts is the sensitivity of the material web to be processed. The levers with the pressure elements  38 ,  48  arranged on their heads press elastically onto the material web  2 . The belts  37  are also elastic and flexible over their widths making it possible to wind the material web  2  onto the winding core  25 . In contrast to the prior art with the contact rolls or the winding baskets, the differing tension of the material web  2  can adapt over the width of the many belts, and/or owing to the elasticity of the belts with the belt tensioners, the tension across the width of the material web is not applied uniformly onto the material web since the web can have a differing thickness locally owing to the production method. 
         [0030]    Shown in  FIG. 1 , and enlarged in  FIG. 4 , is the arrangement of the three support plates  23 ,  23 ′ and  23 ″ between which the levers, rolls and deflection rolls are arranged. As can be seen, the rolls  36  and/or  46 , as well as the deflection rolls  35  and/or  45 , respectively arranged between two levers, are arranged on one or two joint axes which are not shown herein and are arranged between the support plates  23  and  23 ′ and/or  23 ′ and  23 ″. 
         [0031]    According to  FIG. 3 , the feeder system  20  is opened for the “feeding from above” of the material web to form a coil. For this, the adjustment means  33  and  43  pull the levers  31 ,  41  downward, so that the heads  34  and  44  are pivoted away from the winding core  25  because of the pivoting point  32  and  42 . The first and the second belt feeders  30 ,  40  thus release the winding core  25 . The belt  37  only partially moves around the winding core  25 . According to  FIG. 2 , the material web  2  is conducted over the clamping roll  3  and the roll  4  to the guide rolls  5 ,  6  and from there is guided via the roll  11  into the feeder system  20 . In the process, the material web  2  enters the feeder system  20  from above, meaning in clockwise direction, to wind around the winding core  25 . The first belt feeder  30  remains in the opened position. The belt or the belts  37  grip the material web  2  and guide it around the winding core  25 . So that the material web  2  realizes a complete rotation around the winding core  25 , the second belt feeder  40  fits itself against the winding core  25 . For this, the adjustment means  43  presses the lever  41  onto the winding core  25 , thus causing the belt  37  to push more against the winding core  25  and the pressure elements  48  to press the material web  2  against the winding core  25 . The belt  37  thus wraps itself around the winding core  25  with a wrapping angle of more than 270°. So that the starting portion of the material web  2  is guided completely, if possible, the spring plates rest in the manner of fingers on the material web  2  and press this material web  2  onto the winding core  25 . Once a predetermined length of a material web  2  to be wound is reached, the second belt feeder  40  can be pivoted once more to the open position. Owing to two coupling links  47 , the lever  41  can only realize a limited pivoting movement, so that the diameter is limited up to which the material web  2  is pressed against the winding core  25  by the second belt feeder  40 . For this exemplary embodiment, a diameter of 110 mm, for example, cannot be exceeded for winding the material web  2  around the winding core  25 . A cutting device  14  (see  FIG. 2 ) can cut the material web  2  following the completion of the winding operation and once a predetermined length is reached. 
         [0032]    Feeding the material web  2  “from below” takes place as previously described in connection with  FIG. 3  by opening the feeding system  20 . For this, the adjustment means  33  and  43  pull the levers  31 ,  41  downward, so that via the pivoting points  32  and  42 , the heads  34  and  44  are pivoted away from the winding core  25 . The first and the second belt feeders  30 ,  40  thus release the winding core  25 . The belt  37  moves only partially around the winding core  25 . According to  FIG. 5 , the material web  2  enters the feeder system  20  from below, meaning in counter-clockwise direction around the winding core  25 . The second belt feeder  40  remains in the opened position. The belt or the belts  37  grip the material web  2  and guide it around the winding core  25 . So that the material web  2  executes a complete rotation around the winding core  25 , the first belt feeder  30  fits itself against the winding core  25 . For this, the adjustment means  33  presses the lever  31  onto the winding core  25 , thus causing the belt  37  to fit itself more against the winding core  25  and the pressure elements  38  to press the material web  2  against the winding core  25 . The belt  37  thus wraps itself around the winding core  25  with an angle of more than 270°. So that the starting segment of the material web  2  is guided as completely as possible, the pressure elements  38  which are here embodied as spring plates, rest in the manner of fingers on the material web  2  and press the material web against the winding core  25 . Once a predetermined length for winding up a material web  2  is reached, the first belt feeder  30  can again be pivoted to the open position. Since the lever  31  is embodied as a two-sided, centrally positioned lever, it can carry out a large pivoting movement, so that a large, variable winding diameter is possible, up to which the material web  2  is pressed by the first belt feeder  30  against the winding core  25 . For this exemplary embodiment, a material web  2  can be wound around a winding core  25  up to a diameter of 40-120 mm. 
         [0033]    Depending on the strength or rigidity of the material web  2 , it can also be supplied for both winding variants via a guide sheet, not shown herein, to the winding core  25 . 
         [0034]    In contrast to the prior art, both belt feeders  30 ,  40  can also be operated separately, wherein a material web  2  can be wound clockwise or counter-clockwise around a winding core  25 . Two winding directions are therefore possible. As a result of the rotational direction for the winding of the material web  2 , the belt feeder  30 ,  40  is engaged, for which the head  34 ,  44  points in the winding direction. The second belt feeder  40  points with its head  44  in the direction past the winding core  25  and thus winds up the material web  2  in clockwise direction for the “feeding from above.” The first belt feeder  30  points with its head  34  in counter-clockwise direction past the winding core  25  and thus winds up the material web counter-clockwise for the “feeding from below.” Even if a belt feeder ( 30  or  40 ) is not engaged, its head ( 34  or  44 ) functions as a deflection point for the belt  37 , so that the wrap-around angle is maximized. 
         [0035]    Of course, it is also possible to design the second belt feeder  40  with a changeable lever geometry, similarly as for the first belt feeder  30 , so that both belt feeders  30 ,  40  can realize a variable winding diameter range. The embodiment shown herein, however, has the advantage that because of the limited pivoting range of the second belt feeder  40 , the complete feeder system  20  requires less space since, otherwise, the feeder system  20  must be positioned farther from the frame  7  of the winding machine  1 , corresponding to the enlarged pivoting range of the levers  41 ,  41 ′. The geometric conditions are thus changed since the feeder system  20  can also be pivoted around the pivoting point  21 . Corresponding to the different client requirements, a compact winding machine can be provided because of the differing lever system, or a winding machine with variable winding diameter, wherein for both types of embodiment it is possible to wind in two directions. 
         [0036]    Corresponding to the embodiment shown in  FIG. 1 , each belt feeder  30 ,  40  is provided with a plurality of side-by-side arranged levers and belts. As a result, the tension over the width of the material web can be adapted quite easily. A further advantage is that several strips of material and/or a material web divided into strips can be wound simultaneously. 
         [0037]    A further improvement can be achieved in that the deflection rolls  35  and  45  are designed in part to have a diameter large enough so that the deflection rolls  35  and/or  45  on the head  34 ,  44  of the levers  31 ,  41  rest on the material web  2  during the winding operation and not the belt  37 . The wrapping angle is slightly reduced as a result, but a malfunction due to a jammed belt  37  is no longer possible. 
         [0038]    It will be understood that the above description of the present invention is susceptible to various modifications, changes and adaptations, and that the same are intended to be comprehended within the meaning and range of equivalents of the appended claims.