Abstract:
The invention relates to a winding material expansion device ( 10 ). In the winding material expansion device ( 10 ) a winding material ( 5 ) is guided in a meandering manner between rollers ( 16, 17, 18, 19 ) for guiding and/or expanding the winding material ( 5 ). For simplifying a removal of the winding material ( 5 ) from the winding material expansion device ( 10 ) and/or introducing the winding material ( 5 ) into the winding material expansion device ( 10 ) rollers ( 16, 17 ) are displaceable, in particular pivotable, such that in a removal position of the rollers ( 16, 18 ) the winding material is freely accessible.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application claims priority to co-pending German Patent Application No. DE 10 2012 215 772.7 entitled “Spulgut-Spreizeinrichtung”, filed Sep. 5, 2012. 
       FIELD OF THE INVENTION 
       [0002]    The invention relates to a winding material expansion device or winding material guide device, a traversing device, a winding machine and a method for operating a winding machine. 
         [0003]    The invention particularly relates to expansion of the winding material on the supply path thereof to form a coil to be wound. For example, the winding material is a fibre bundle of any type which is intended to be expanded before being applied to the outer face of the coil, with it being possible for expansion to be intended to form uniformly thick and wide “tapes” of the fibres which are advantageous for the transfer and/or the further processing. It is also possible that simple guiding through a winding material guide device is intended for so-called prepreg (pre-impregnated fibres) without further expansion being intended to take place in this instance. Instead, a width and/or geometry of the prepreg present is intended to be maintained if possible and/or particular consideration is intended to be given to the guiding forces applied to the prepreg. 
       BACKGROUND OF THE INVENTION 
       [0004]    According to EP 0 459 681 B2, in a winding machine for fibre bundles the coil may be driven via the spindle or via a pressing roller. It is further set out in EP 0 459 681 B2 that, alternatively, the coil or the thread guide may carry out the traversing movement necessary during the winding. The winding material mentioned in EP 0 459 681 B2 involves fibre bundles (multi-filaments). In this instance, the fibres are already expanded in a manner which is not specified in greater detail so that the winding material is already supplied to the traversing device in a tape-like state. The fibres are fixed in the expanded position by impregnation or by being embedded in a matrix, for example, comprising epoxy resin or non-saturated polyester, so that a tape-like geometry is established. EP 0 459 681 B2 describes the use of rollers which are supported rotatably on a traversing device and the axes of rotation of which are rotated in a horizontal plane successively through a total of 90° in order to rotate the extension direction of the tape-like winding material from an extension direction determined by a supply roller to an extension direction which is orientated parallel with the rotating coil or spindle. That rotation may allow the subsequent application of the winding material to the coil during the winding process. Alternatively, EP 0 459 681 B2 proposes that the winding material be rotated by helical sliding faces. 
         [0005]    EP 1 584 594 B1 discloses a winding machine, in which a plurality of coils can be wound in a parallel manner on a plurality of winding stations. The winding material is a fibre bundle, for example, comprising carbon fibres, glass fibres, aramide fibres, inter alia, which may have from 3000 to 24,000 filaments. This may also be a prepreg, an (additional) expansion of the prepreg being able to be carried out by means of a winding material expansion device. EP 1 584 594 B1 describes the problem in that a previously expanded, tape-like fibre bundle is acted on in a transverse direction during the use of known winding machines with a traversing device which is not adapted to the fibre bundles, whereby a predetermined shape of the tape-like winding material is lost and torsion thereof may be brought about. EP 1 584 594 B1 proposes a modification of the traversing device in such a manner that an expansion extent of the fibre bundle in the region of the traversing device is intended to be maintained or even further increased. According to EP 1 584 594 B1, winding material is supplied to the traversing device from a roller which is supported in a manner fixed to a machine frame and with an axis of rotation which is orientated parallel with the axis of rotation of the coil. In the region of the traversing device, the expansion extent is rotated through 90° by means of a cylindrical roller which is orientated transversely relative to the axis of rotation of the coil. Subsequently, the winding material reaches the pressing roller, in the region of which the winding material is applied to the coil via a conical roller and an additional cylindrical roller. The expansion extent is again rotated back through 90° by means of the conical roller and the additional cylindrical roller, for which purpose the conical roller is orientated at an acute angle relative to the axis of rotation of the coil and the additional cylindrical roller is orientated parallel with the axis of rotation of the coil. Additional information relating to filament numbers of the fibre bundles, fibre diameters, roller contours, roller widths and roller thicknesses and fibre materials may be taken from EP 1 584 594 B1. 
         [0006]    The publication DE 41 30 809 A1 relates to another technical field, i.e. a textile machine in the form of a carding machine, in which a fibre tape is intended to be guided and compacted between a tape forming device and a funnel which compacts the fibre tape. A calender roller pair is arranged downstream of the funnel. DE 41 30 809 A1 describes measures for correctly guiding and compacting the fibre tape even at high supply speeds with the object of preventing the air which is pressed out of the fibre tape during the compaction process in the funnel from inhibiting the discharge process through the calender rollers, whereby a breakage of the fibre tape may result. 
         [0007]    The publication DE 24 18 234 A1 which is also relates to another technical field describes a tape store for metal tapes. 
         [0008]    Additional prior art is known from U.S. Pat. No. 4,989,799 A and JP H10-330 038 A. 
       OBJECT OF THE INVENTION 
       [0009]    An object of the invention is to provide 
         [0010]    a device for expanding a winding material and/or guiding a winding material, 
         [0011]    a traversing device, 
         [0012]    a winding machine and 
         [0013]    a method 
         [0014]    which is improved with regard to 
         [0015]    the guiding and expansion of the winding material, 
         [0016]    the forces applied to the winding material, 
         [0017]    the conditions relating to structural space, 
         [0018]    the introduction of the winding material into the winding material expansion device or winding material guide device and/or 
         [0019]    the removal of the winding material from the winding material expansion device or winding material guide device. 
       SUMMARY OF THE INVENTION 
       [0020]    According to the invention, the device for guiding and/or expanding the winding material has at least one first roller and at least one second roller of any surface contour and orientation of the axes of rotation. Between these rollers the winding material is guided in a meandering manner. The term “meandering guiding” is intended to be understood in that the winding material is wound around at least one of these rollers in a partial peripheral region in the clockwise direction and the winding material is wound around at least one other roller in a partial peripheral region in a counter-clockwise direction. That meandering guiding can bring about expansion and/or guiding of the winding material, as also described, for example, in the prior art mentioned in the introduction. 
         [0021]    It is generally intended to keep the spacing of the rollers of the winding material expansion device or winding material guide device as small as possible in order to minimise the structural size. However, it is advantageous for introduction and removal of the winding material into/out of the winding material expansion device or winding material guide device if the spacing of the rollers is as large as possible. Consequently, there is an conflict of objectives which apparently cannot be resolved and which requires individual adaptation in accordance with the different applications. 
         [0022]    That conflict of objectives may be solved in the context of the present invention in that at least one first roller does not have an axis of rotation which is fixed relative to the moved portion of the traversing device but instead it is movable. Consequently, the at least one first roller can be arranged for the meandering guiding between the rollers in a winding position in which the rollers are arranged as close to each other as desired without the conditions for the removal or introduction of the winding material having to be considered. By at least one first roller being moved into a removal and/or introduction position, the spacing of the first and second rollers can then be changed, which allows simplified removal and/or introduction of the winding material. In this instance, the removal and/or introduction position may be selected in such a manner that, for example, although the spacing of the rollers is increased, the winding material is still guided between those rollers in a meandering manner, but with the wrapping angle of the winding material on the rollers then being able to be reduced. In this instance, consequently, a “meandering width” of the meandering guiding of the winding material between the rollers changes. However, the removal and/or introduction position is preferably constructed in such a manner that the moved first roller(s) is/are moved out of contact with the winding material, so that the winding material then only contacts the second rollers or even no longer has to have any further contact with any roller. 
         [0023]    It is possible that the degree of freedom of movement of at least one first roller provided according to the invention is also used for additional or alternative purposes. In order to set out merely a non-limiting example, the guiding and expanding action of the winding material guide device or winding material expansion device can also be adapted by means of the movement of the first roller and therefore the change in the distance of the first and second rollers, or an adaptation to the respective winding material may be brought about. In this instance, the movement of the at least one first roller does not take place between operating positions which are in the form of a winding position and removal and introduction position. Instead, those operating positions are then winding positions which are intended for different operating modes of the winding machine. 
         [0024]    It is possible for the movement between the first and second operating position to be brought about manually by an operator. According to an additional proposal of the invention, an actuator is provided on the winding material expansion device or winding material guide device. By means of the actuator the movement of the at least one first roller between the two operating positions can be brought about. This actuator may be controlled as required by a switch being actuated by an operator. However, automatic actuation of the actuator is preferably brought about and is adapted to the operation of the winding machine. For this purpose, the actuator can be controlled by a suitable control unit in accordance with the operating variables which relate to the winding process and/or a changing process. 
         [0025]    There are various options for constructing the actuator. In order to set out merely a small number of non-limiting examples, the actuator may be constructed in an electromotive or hydraulic manner. In a preferred construction, the actuator is a pneumatic actuating cylinder. In this instance, in some cases it is possible to exploit the fact that a pneumatic operating pressure is anyway present at a winding machine or at the winding material expansion device or winding material guide device. It is possible to use the pneumatic operating pressure in the pneumatic actuating cylinder without additional complexity having to be involved in order to provide the driving energy of the actuator. On the other hand, in some cases the actuation of the actuator can be controlled or regulated readily by means of a suitable pneumatic control circuit, electrically operated valves also being able to be used therein. 
         [0026]    For an additional proposal of the invention the actuator is built by a turret of the winding machine. This construction makes use of the fact that a rotation of the turret is carried out precisely at the time at which a coil is completely wound and the change to an empty spindle (under some circumstances with a sleeve arranged thereon) is carried out. Under some circumstances, however, it is also desirable to move the movable first roller(s) to the removal or introduction position precisely at that time. The turret may be used in this instance simply to control the movement so that the actuator is controlled in accordance with the rotation angle of the turret. In a preferred construction of the invention, however, the movement of the turret is directly used, for example, by a stop, a guide rail or an actuation cam of the turret, in order to bring about the movement of the at least one first roller between the positions thereof. 
         [0027]    It is possible for a plurality of first rollers to carry out the same movement or different movements (with regard to the magnitude and the direction). 
         [0028]    The movement of at least one first roller may be carried out along any linear or curved movement axis which determines a degree of freedom. In order to set out merely one example, the rollers can be moved together in translation away from the fixed rollers so that a gap is formed between the moved rollers and non-moved rollers. In this instance the winding material can be introduced and removed in a direction parallel with the orientation of the rotation axes of the rollers between the rollers. 
         [0029]    In an exemplary embodiment of the invention, the movement of the at least one first roller is carried out about a pivot axis which defines a pivoting degree of freedom. Under some circumstances, such a pivoting degree of freedom can be realised in very simple manner, wherein in contrast to a translation movement (for which the moved first rollers often have to be supported at both sides with a resultant reduction in the accessibility of the first rollers) it is necessary to link the first rollers at a pivot bearing or at a pivot axis only in an end region of the rollers. Consequently, the other end region of the first roller(s) may also remain freely accessible. The introduction and/or the removal may also thereby be simplified. On the other hand, curved movements of the first roller(s) is/are possible for a pivot movement in accordance with the arrangement of the pivot bearing, which may have an advantageous effect on the structural space. The options for arranging the bearing for the movement of the at least one first roller and the actuator may also be extended under some circumstances by using a pivoting degree of freedom when compared to differently constructed degrees of freedom for the movement of the at least one first roller. 
         [0030]    Merely by way of example, reference is made to two optional orientations of the pivot axis of the pivoting degree of freedom:
       For one embodiment of the invention, the pivot axis of the pivoting degree of freedom is orientated transversely relative to a conveying direction of the winding material through the winding material expansion device or winding material guide device. If the winding material extends approximately vertically in the winding material expansion device or winding material guide device, the first rollers can be pivoted out, similarly to a door, laterally from associated pairs of non-movable second rollers by means of a pivot axis orientated in such a manner. In this instance, the pivot angle may be less than 90°, may be 90° or may even be more than 90°. Such a pivot axis may allow introduction and/or removal of the winding material to be able to be carried out not only in the direction of the axes of rotation of the rollers but also perpendicularly relative thereto or at an acute angle thereto.   For another embodiment according to the invention, the pivot axis of the pivoting degree of freedom is orientated parallel with a conveying direction of the winding material through the winding material expansion device or winding material guide device.       
 
         [0033]    It is possible for the actuator to be connected directly to the first roller(s). However, it is also possible that a plurality of actuators is responsible for different first rollers. 
         [0034]    In another embodiment of the invention, a drive mechanism is interposed or located between the actuator and the at least one first roller. This may be, for example, a gear type connection, a tappet connection or stem connection, a toothed rod connection, a spindle drive, a multiple link chain, inter alia. The reasons for using a drive mechanism may vary. For example, by means of the drive mechanism a change of the drive direction between the actuator and the first roller(s) may be brought about, a step-up action or a step-down action may be brought about, a drive characteristic between the movement of the actuator and the movement of the first roller(s) may be provided, a spaced arrangement of the actuator from the first roller(s) may be provided, inter alia. 
         [0035]    The present invention also covers that the drive connection between the actuator and first roller(s) permanently exists, that is to say, for example, also during the winding process of a coil, whilst the actuator is not actuated. In a particular embodiment of the invention, the drive mechanism is releasable, which may be carried out, for example, in an automatic manner by means of selective control, movement control or manually. It is thereby possible for the drive mechanism only to connect the actuator to the first roller(s) when the actuator actually has to be actuated. In order to set out merely a non-limiting example of the invention, the traversing device for an imminent change with the requirement of removing the winding material from the winding material expansion device or winding material guide device can be moved into a traversing position which forms a changing position in which the drive mechanism connects the actuator to the first roller(s), for example, by means of a sliding contact or a positive-locking engagement. If, however, the drive mechanism is intended to be released, the traversing device is moved out of the traversing/changing position mentioned, whereby the connection is then released, in particular by disengagement of the positive-locking connection or removal or blocking of the sliding contact. 
         [0036]    For a particular embodiment of the drive mechanism, the drive mechanism has a lever. The lever can be pivoted about a pivot axis. The pivot axis of the lever is orientated parallel with an axis of rotation of the coil to be wound. The lever (which may be constructed in a linear or curved manner) has lever portions at both sides of the pivot axis. The actuator acts (directly or indirectly) on the first lever portion. The at least one first roller is arranged on the second lever portion. Depending on the geometry of the lever and length of the lever portions, a force step-up or a force step-down can be brought about and the drive movement from the actuator located at a remote location can be transferred to the at least one first roller: Also a redirection of the actuation direction of the actuator and the movement direction of the first roller(s) can be brought about. There are various possibilities for acting on and cooperating with the first lever portion in order to bring about the desired movement. For example, the actuator may be directly linked or may be linked with another actuation element which is coupled with the actuator. 
         [0037]    For a particular embodiment of the invention, a rotatable cam acts on the first lever portion. Consequently, the pivoting of the lever is caused by a sliding movement of the cam face of the rotatable cam relative to a counter-face of the first lever portion. Depending on the geometry of the cam, different dependencies may be brought about between a rotation of the cam relative to a rotation of the lever, whereby non-linear characteristics can also be produced. 
         [0038]    The cam can be driven in various manners. One embodiment of the invention proposes that the cam is driven by a crank to which the actuator is linked. 
         [0039]    It is possible for a drive movement, in particular via the cam mentioned, to be only used for one single device for guiding and/expanding the winding material. For a particular proposal of the invention, however, the cam is connected to another cam via a coupling shaft so that the cam and the additional cam are rotated together. The additional cam is used in another winding material expansion device or winding material guide device in order to also bring about a movement of at least one first roller of the additional winding material expansion device or winding material guide device. 
         [0040]    For one embodiment the cam and the additional cam have the same cam geometry and the same cam angle, so that it is readily ensured via the connection by the coupling shaft that a common and synchronous movement of the at least one first roller of the two winding material expansion devices or winding material guide devices is carried out. 
         [0041]    It is also possible for the actuator, the at least one cam, the coupling shaft and/or the crank to be articulated or secured to the traversing device in such a manner that they are moved with the traversing device. For an exemplary embodiment of the invention, the actuator, the at least one cam, the coupling shaft and/or the crank is/are articulated or secured to the machine frame or to a portion of the traversing device secured to the machine frame. This allows simplified control and supply of power to the actuator. It further results in a reduction of the moved mass for producing the traversing movement. However, a guide carriage, a bearing or the pivot bearing for the movement of the at least one roller can be arranged on a structural element of the traversing device, which structural element is moved with the traversing device. 
         [0042]    Another solution to the problem addressed by the invention is provided by a traversing device for a winding machine which has at least one device for guiding and/or expanding winding material of the type explained above. 
         [0043]    Another solution to the problem addressed by the invention is provided by a winding machine which has at least one traversing device of the aforementioned type. 
         [0044]    In principle, the winding machine may correspond to any construction type known per se. For one proposal according to the invention, the winding machine is in the form of a turret winding machine. Two spindles are rotatably retained on a turret. In an alternating fashion coils can be wound on the spindles at a winding station. If, however, a coil which is completely wound in the region of the winding station is moved to a changing station by rotating the turret, it is possible to remove the completely wound coil. Under some circumstances, a new sleeve is also fitted to the spindle in the region of the changing station if necessary. It is possible for the winding material for the change to be manually moved for the winding process on a spindle to a winding process on the other spindle, which may be carried out, for example, by means of a suction gun. However, the change is preferably carried out in an automatic manner. In this instance the movement of at least one first roller of the winding material expansion device or winding material guide device is also used to simplify the transfer of the winding material during the changing process with a discharge from the winding material expansion device or winding material guide device and the re-introduction of the winding material. 
         [0045]    For a particular embodiment according to the invention, the winding machine comprises a changing device via which it is possible to automatically move the winding material from a spindle with a completely wound coil to another spindle, a catch device for catching the winding material during the changing process as described, for example, in EP 1 525 150 B1, a separation device for separating the winding material after the changing process and/or a change-over thread guide via which in the removal position of the at least one movable first roller the winding material is removed from the winding material expansion device or winding material guide device. 
         [0046]    Another solution to the problem addressed by the invention is provided by a method for operating a winding machine having a traversing device, as previously explained. The winding machine further has a turret and two spindles which are retained by the turret and which can be moved between a winding station and a changing station by a rotation of the turret. It is possible for a change-over thread guide also to be provided in such a winding machine, which change-over thread guide supplies the winding material at the end of a winding process of a coil on a spindle to the other spindle (or a sleeve arranged thereon). The change-over thread guide is also able to carry out removal from the winding material expansion device or winding material guide device and/or introduction therein in an automatic manner during the changing action. 
         [0047]    The method according to the invention has the following method steps: 
         [0048]    Firstly, a coil is wound in the region of a winding station. In this instance, the at least one movable first roller of the winding material expansion device or winding material guide device is in the winding position in order to ensure the supply of the winding material in the desired state of the winding material. If the coil is completely wound, the at least one movable first roller of the winding material expansion device or winding material guide device moves from the winding position into the removal and introduction position. Subsequently, the winding material is removed from the winding material expansion device or winding material guide device. This may occur before, during or after the initiation or implementation of the changing process, that is to say, before, during or after the transfer of the winding material from the completely wound coil to the empty spindle. When the winding process begins on the empty spindle, for the method according to the invention the winding material is (re-)introduced into the winding material expansion device or winding material guide device. In order to guarantee the supply of the winding material in the desired state of the winding material for the winding process now beginning, the at least one movable first roller of the winding material expansion device or winding material guide device is moved from the removal and introduction position into the winding position. 
         [0049]    Advantageous developments of the invention result from the claims, the description and the drawings. The advantages of features and of combinations of a plurality of features mentioned at the beginning of the description only serve as examples and may be used alternatively or cumulatively without the necessity of embodiments according to the invention having to obtain these advantages. Without changing the scope of protection as defined by the enclosed claims, the following applies with respect to the disclosure of the original application and the patent: further features may be taken from the drawings, in particular from the illustrated designs and the dimensions of a plurality of components with respect to one another as well as from their relative arrangement and their operative connection. The combination of features of different embodiments of the invention or of features of different claims independent of the chosen references of the claims is also possible, and it is motivated herewith. This also relates to features which are illustrated in separate drawings, or which are mentioned when describing them. These features may also be combined with features of different claims. Furthermore, it is possible that further embodiments of the invention do not have the features mentioned in the claims. 
         [0050]    The number of the features mentioned in the claims and in the description is to be understood to cover this exact number and a greater number than the mentioned number without having to explicitly use the adverb “at least”. For example, if an element is mentioned, this is to be understood such that there is exactly one element or there are two elements or more elements. Additional features may be added to these features, or these features may be the only features of the respective product. 
         [0051]    The reference signs contained in the claims are not limiting the extent of the matter protected by the claims. Their sole function is to make the claims easier to understand. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0052]    The invention is explained and described in greater detail below with reference to exemplary embodiments illustrated in the Figures. In the drawings: 
           [0053]      FIG. 1  is a schematic side view of a winding machine having two winding material expansion devices, the winding material expansion device being in the first operating position or winding position. 
           [0054]      FIG. 2  is a front view of the winding machine according to  FIG. 1 . 
           [0055]      FIG. 3  shows a detail III of the winding machine according to  FIG. 1 . 
           [0056]      FIG. 4  is a side view of the winding machine according to  FIG. 1 , the winding material expansion device being in the removal and/or introduction position. 
           [0057]      FIG. 5  is a front view of the winding machine according to  FIG. 4 . 
           [0058]      FIG. 6  shows a detail VI of the winding machine according to  FIG. 4 . 
           [0059]      FIG. 7  is a side view of another embodiment of a winding machine. 
           [0060]      FIG. 8  is a front view of the winding machine according to  FIG. 7 . 
           [0061]      FIG. 9  shows a detail IX of the winding machine according to  FIG. 8 . 
           [0062]      FIG. 10  is a schematic view of a method for operating a winding machine according to the invention having a turret and automatic changing process. 
       
    
    
     DETAILED DESCRIPTION 
       [0063]      FIG. 1  is a side view of a winding machine  1  having a machine frame  2 , in this instance in a viewing direction counter to the z-axis. A spindle  3 , on which two coils  4   a ,  4   b  are wound beside each other, optionally with the interposition of a catch device and/or a sleeve being interposed, extends horizontally in the direction of the x axis. Winding material  5   a ,  5   b  is continuously supplied to the coils  4   a ,  4   b  on parallel winding paths. The parallel winding paths of the winding material  5   a ,  5   b  extend via
       guide rollers  6   a ,  6   b , which have in this instance a concave surface contour and which are supported rotatably relative to the machine frame  2  with an axis of rotation extending parallel to the x axis,   traversing devices  7   a ,  7   b , which carry out synchronous traversing movements  8   a ,  8   b  parallel with an axis of rotation  9  of the coils  4   a ,  4   b,      winding material expansion devices or winding material guide devices  10   a ,  10   b  which are a component of the traversing devices  7   a ,  7   b  (referred to below merely as “winding material expansion device”) and   a pressing roller  11 .       
 
         [0068]    The additional structure of the traversing device  7  is not illustrated in the Figures. In this regard, reference is made to the known prior art for the construction of traversing devices. 
         [0069]    In the region of the winding material expansion devices  10   a ,  10   b , the winding material is conveyed in a conveying direction  12   a ,  12   b  which is orientated parallel with the y axis in this instance. If, as illustrated in  FIG. 1 , in the viewing direction selected in  FIG. 1 , the winding material  5  actually passes linearly through the winding material expansion device  10 , the conveying direction  12   a ,  12   b  corresponds to the orientation of the winding material in this view. However, if the orientation of the winding material  5  changes in the region of the winding material expansion device  10  (for example as a result of inclined rollers or non-cylindrical contours of the rollers) the conveying direction  12  describes the central or averaged orientation of the winding material  5  in the region of the winding material expansion devices  10   a ,  10   b.    
         [0070]    The winding material expansion devices  10  each have two upper guide rollers  13 ,  14  (cf.  FIGS. 2 and 3 ), between which a gap  15  of constant width is formed. The winding material  5  passes through the gap  15 . The outer lines of the guide rollers  13 ,  14  delimiting the gap  15  are orientated transversely relative to the longitudinal extension of the winding material  5  and transversely relative to the conveying direction  12  and the direction of the traversing movement  8 . During the traversing movement  8 , a (slight) redirection is brought about in the region of the guide rollers  13 ,  14 , whereby expansion of the winding material  5  can be brought about or increased. In the event that the winding material  5  travels through the guide roller  6  in an already expanded state, the extent of the expansion is rotated through 90° in the region of the guide rollers  13 ,  14 . In this instance the guide rollers  13 ,  14  are able to maintain or increase the magnitude of the expansion. Downstream of the guide rollers  13 ,  14  and the gap  15 , the winding material expansion device  10  has rollers  16 ,  17 ,  18 ,  19 . The axes of rotation of the rollers  16 ,  17 ,  18 ,  19  are orientated for simplicity parallel with each other and parallel with the x axis. The outer faces of the rollers  16 ,  17 ,  18 ,  19  are of cylindrical form (without this necessarily being the case). In this instance, the axes of rotation of the rollers  16 ,  17 ,  18 ,  19  are arranged in a plane which is orientated parallel with the x-y plane. This is also not necessarily the case. 
         [0071]    As can be seen in  FIG. 2 , the winding material  5  adjoins the outer face of the roller  16  downstream of the guide rollers  13 ,  14  in the region of a 9 o&#39;clock position and follows that outer surface in a counter-clockwise direction up to an approximately 6 o&#39;clock position where the winding material  5  is then supplied to the roller  17  at a 12 o&#39;clock position. From that position, the winding material  5  is wound around the roller  17  in a clockwise direction as far as approximately a 6 o&#39;clock position, from which the winding material  5  reaches approximately a 12 o&#39;clock position of the roller  18 . On the roller  18 , the winding material  5  is wound around the outer face in a counter-clockwise direction up to a 6 o&#39;clock position, where the winding material  5  again disengages from the roller  18  and contacts the roller  19  in the region of a 12 o&#39;clock position. Depending on the arrangement of the pressing roller  11 , the winding material  5  can then be disengaged from the roller  19  at various positions (in  FIG. 2 , approximately in a half past four position). Consequently, for the embodiment illustrated the winding material  5  has three turning points on the conveying path through the winding material expansion device  14 . At the turning points the conveying changes from conveying in a clockwise direction to conveying in a counter-clockwise direction and vice versa. Those turning points are arranged in the region of the intermediate spaces  20 ,  21 ,  22  which are formed between adjacent pairs of rollers  16 - 17 ,  17 - 18  and  18 - 19 . Accordingly, a meandering path is given by the rollers  16 ,  17 ,  18 ,  19  for the winding material. It can be seen in  FIG. 3  that the intermediate spaces  20 ,  21 ,  22  may be selected to be very small so that a compact construction of the winding material expansion device  10  is provided. It must simply be avoided that the rollers  16 - 19  come into contact with each other or that the winding material  5  becomes “jammed” between the rollers  16 - 19 . 
         [0072]    It can be seen (for example in the view according to  FIG. 2 ) that removing the winding material from the winding material expansion device  10  would be more difficult without the steps according to the invention described below, which is due to the small spacing of the rollers  16 - 19  and the small extent of the intermediate spaces  20 - 22  in the direction of the y axis. The same applies to the introduction of the winding material  5  between the rollers  16 - 19 . 
         [0073]    For this reason, the rollers  16 ,  18  do not have axes of rotation being fixed to the traversing device  7 . Instead, those rollers  16 ,  18  can be moved or displaced according to the invention transversely to the axis of rotation thereof, which is brought about in this instance by a pivoting movement.  FIGS. 1 to 3  show the rollers  16  to  18  in a first operating position which is a winding position  23 . However, the rollers  16 ,  18  in  FIGS. 4 to 6  are illustrated in a second operating position which is a removal and/or introduction position  24 . To that end, the rollers  16 ,  18  and the axes of rotation thereof can be pivoted about a pivot axis  25 . According to  FIG. 4 , the rollers  16 ,  18  are pivoted by a pivot angle of 90° (but different pivot angles also being possible). In the removal and/or introduction position  24 , the rollers  16 ,  18  are out of contact with the winding material  5  so that the winding material  5  conveyed from the guiding rollers  13 ,  14  directly reaches the roller  17 , where a redirection in the clockwise direction can then be carried out to a reduced extent. From the roller  17 , the winding material in an approximately 3 o&#39;clock position then reaches a 3 o&#39;clock position of the roller  13  with conveying approximately in a conveying direction  12 . From the roller  19 , the winding material then reaches the pressing roller  11 . It can be seen particularly in  FIG. 4  that the removal of the winding material  5  from the winding material expansion device  10  is readily possible. For this purpose, for example, the winding material  5  can be removed vertically relative to the plane of the drawing according to  FIG. 4  from the rollers  17 ,  19  and from the gap  15  between the guide rollers  13 ,  14 . This corresponding applies to the introduction of the winding material into the winding material expansion device  10 . After the winding material has been introduced, as illustrated in  FIG. 4 , the rollers  16 ,  18  can be pivoted back out of the removal and/or introduction position  24  according to  FIGS. 4 to 6  into the winding position  23  according to  FIGS. 1 to 3 . With the reverse pivoting movement of the rollers  16 ,  18 , those rollers  16 ,  18  come into contact with the winding material  5  and “press” the winding material  5  into the intermediate spaces between the rollers  17 ,  19 , whose axes of rotation are fixed relative to the traversing device  7  until the state according to  FIGS. 1 to 3  is reproduced. 
         [0074]    The movable rollers  16 ,  18  are here also named “first rollers” whereas the fixed rollers  17 ,  19  are also named “second rollers”. 
         [0075]      FIGS. 7 to 9  show an alternative embodiment of a winding machine  1 , for which in part the same reference numerals have been used as for the embodiments according to  FIGS. 1 to 6 , if the structural elements indicated with that reference numeral have the same function, serve the same purpose or are constructed similarly. For this embodiment, the winding machine  1  is formed with a turret  26 , on which two spindles  3   a ,  3   b  are retained in opposite positions. For the operating state according to  FIG. 8 , the spindle  3   a  is in a winding station  27 . In the region of the winding station  27  a coil can be wound whilst the spindle  3   b  is in the region of a changing station  28 . At the changing station  28  it is possible to remove a completely wound coil from the spindle  3   b  and the spindle  3   b  can be prepared for a subsequent winding process, in particular by a sleeve being fitted thereon. By rotating the turret  26 , the spindles  3   a ,  3   b  can in an alternating fashion be moved into the region of the winding station  27  and the region of the changing station  28 . 
         [0076]    As can be seen particularly in  FIG. 9 , additional guide rollers  29 ,  30  are provided in addition to the guide rollers  13 ,  14  in the winding material expansion device  10 . The axes of rotation of the guide rollers  29 ,  30  form an acute angle relative to the axes of rotation of the guide rollers  13 ,  14  in a horizontal plane. Furthermore, in this instance the winding material expansion device  10  only comprises the rollers  17 ,  19  (building “second rollers” in the sense of the present invention) with an axis of rotation fixed in relation to the traversing device  7  and the roller  18  (building the only “first roller” in the sense of the present invention) whose axis of rotation can be moved relative to the traversing device  7 . Here the additional roller  16  with a movable axis of rotation is not present. 
         [0077]    For this embodiment the degree of freedom of movement of the roller  18  is provided in a manner different from the one in accordance with  FIGS. 1 to 6 . In at least one end region, the roller  18  is supported rotatably on a lever portion  31  of a lever  32 . The lever  32  is supported pivotably about a pivot axis  33  having an orientation parallel with the axis of rotation of the coil  4  and transversely relative to the conveying direction  12  of the winding material  5 . The pivot movement of the lever  32  about the pivot axis  33  (and therefore the movement of the roller  18 ) is brought about by indirect actuation of the other lever portion  34  of the lever  32  by an actuator  35  as follows. 
         [0078]    A drive mechanism  36  is arranged between the lever portion  34  and the actuator  35 . the drive mechanism  36  is used to transmit the positioning movement and positioning forces of the actuator  35  to the lever portion  34 . The drive mechanism  36  is here formed with a crank  38  which is supported pivotably about a pivot axis  37 . An actuation rod  39  is linked with the end region of the crank  38  facing away from the pivot axis  37 . If the actuator  35  is a pneumatic positioning cylinder, the actuation rod  39  may be formed directly by the piston rod. A cam  40  (which is consequently also pivotable about the pivot axis  37  upon activation by the actuator  35 ) is connected to the crank  38  in a rotationally fixed manner. That connection is preferably brought about by a coupling shaft  42  which is orientated parallel with the axis of rotation of the coil. A cam face  41  of the cam  40  rolls on an associated counter-face of the lever portion  34 , whereby pivoting of the lever  32  can be caused.  FIGS. 7 to 9  show the roller  18  in the removal and/or introduction position  24 . The winding position  23  (which is not illustrated in the Figures) is brought about by actuating the actuator  35 , pivoting the crank  38  and the cam  40  about the pivot axis  37  and by pivoting the lever  32  about the pivot axis  33 . 
         [0079]    For the embodiment illustrated in  FIGS. 7 to 9  (as may be seen in  FIG. 7 ) the actuation rod  39  is linked with a coupling shaft  42  which extends parallel with the axis of rotation of the coils  4  and which carries cams  40   a ,  40   b  in a rotationally fixed manner. For this embodiment, the actuator  35  and the coupling shaft  42  are supported on the machine frame  2  in a manner fixed in position, so that the cams  40   a ,  40   b  also have a fixed position in the direction of the traversing movement  8 . That position of the cams  40   a ,  40   b  is selected in a manner such that the lever  32  with its counter-face being moved with the traversing movement is not able to move into engagement with the cam face  41  of the cams  40   a ,  40   b  during the normal winding process. Consequently, the actuator  35  and the drive mechanism  36  are without effect during the winding process—the drive mechanism is released owing to lack of contact between the cams  40   a ,  40   b  and the lever  32 . If, however, the roller  18  is intended to be moved, the traversing device  7  is controlled in such a manner that a traversing movement  8  is brought about into a traversing position, in which the cams  40   a ,  40   b  move into engagement with the associated levers  32 . It is possible for that traversing position also passed during the traversing process during the winding process, for example when using of a reversing threaded shaft for producing the traversing movement. Contact between the cam  40  and lever  32  is then prevented by a suitable positioning angle of the cam  40 . That traversing position is then preferably located in an end region of the traversing movement. However, it is also possible for that traversing position to be outside the movement range during the winding action. Consequently, a winding position  23  can be selectively maintained. However, also a change of the operating position of the winding material expansion device  10  (in particular from the winding position  23  into the removal and/or introduction position  24  or vice versa) may also be selectively brought about by controlling the traversing device  7  and the actuator  35 . 
         [0080]    For the embodiments illustrated, the axes of rotation of the rollers are all orientated horizontally (without this necessarily having to be the case). Unlike the embodiments illustrated, the rollers may also be cylindrical, convex, concave or conical, or any different surface contour. 
         [0081]    Owing to the provision of the option of moving the rollers, the thread can be removed automatically from the traversing device  7  (here from the winding material expansion device  10 ) in winding machines  1  with a changing device (as described for example in European Patent Application EP 1525150A1) with one or more simultaneously wound packages in order to bring about the changing process. Subsequently the thread can be supplied to those devices again. These actions can be carried out automatically. 
         [0082]    A method for operating a winding machine  1  of this type with a turret  26  and automated changing device can be as follows, cf.  FIG. 10 . 
         [0083]    Firstly, in a method step  44  the winding material  5  is wound to form a coil  4  (or in parallel winding paths to form a plurality of coils). For simplicity, only the winding process of coils in an alternating fashion on two spindles  3   a ,  3   b  of a turret  26  is explained below. During the winding process, the winding material  5  is introduced into the winding material expansion device  10  which is in its winding position  23 . The winding material  5  is wound in a traversing manner by means of the traversing device  7 . A change-over thread guide is in a park position. In a method step  45 , the coil  4   a  is completely wound. This may be detected if the desired quantity of winding material  5  is taken up, which can be detected by a suitable measurement technique. In a method step  46 , the turret  26  is now rotated by a rotation  43 . During this rotation  43  of the turret  26 , the winding material is further traversed and deposited on the completely wound coil  4   a . However, an empty coil  4   b  (optionally with a sleeve arranged thereon) is now located in the winding station  25 . 
         [0084]    In the method step  47 , the actuator  35  is activated, whereby a movement of the rollers  16 ,  18  is brought about and the winding material expansion device  10  is moved from the winding position  23  into the removal and/or introduction position  24 . The winding material expansion device  10  and the winding material  5  still arranged therein are moved into the region of the change-over thread guide so that the winding material  5  can be gripped thereby. At this time, the winding material  5  is only in loose contact with the rollers  16 ,  17 ,  18 ,  19  of the winding material expansion device  10  or without any contact and not being wound around these rollers  16 ,  17 ,  18 ,  19 . In this instance, the winding material  5  is still guided by the traversing rollers. 
         [0085]    In the subsequent method step  48 , the winding material  5  is removed from the winding material expansion device  10  and the winding material  5  is caught on the empty spindle  4   b  (cf. e.g. EP 1 525 150 B1). To that end, the change-over thread guide is moved into the changing position  24 . The winding material  5  is moved by the change-over thread guide into a position which is suitable for the winding material  5  to be able to be caught by the catch device associated with the spindle, whereby the winding material  5  can be retained on an empty sleeve. To that end, the traversing device  7  is in a traversing position which makes it possible for the winding material  7  to be removed by the change-over thread guide. 
         [0086]    In a method step  49 , the winding material  5  is severed. By the winding material  5  being retained on the empty sleeve and the full, completely wound coil  4   a  being further rotated, the tension in the winding material  5  between the completely wound coil  4   a  and the empty coil  4   b  is increased which results in the breakage of the winding material  5  in that region. Suitable cutting devices which can bring about a breakage even at a low level of tension in the winding material  5  can further be provided. 
         [0087]    In a method step  50 , the winding material  5  is placed back into the winding material expansion device  10 . The change-over thread guide is moved into a park position. By the change-over thread guide being moved, the winding material  5  is again placed movably in the winding material expansion device  10 . The fixed rollers  17 ,  19  are either not touched or are only touched movably and without any wrapping action by the winding material  5 . To this end, the winding material expansion device  10  is in the removal and introduction position  24  which makes it possible to introduce the winding material by means of the change-over thread guide. 
         [0088]    In a method step  51 , the movable roller  18  moves from the removal and/or introduction position  24  into the winding position  23 . 
         [0089]    In the subsequent method step  52 , the empty coil  4   b  in the winding station  27  is now wound with operation of the traversing device  7 . At the same time, the completely wound coil  4   a  in the changing station  28  is removed and the empty spindle  3   a  is provided with a new sleeve.