Abstract:
The invention relates to a crumpled paper tube for use as a cushion in packing items, and to a method and apparatus for producing the same.

Description:
RELATED APPLICATIONS  
       [0001]     This application is a divisional of U.S. patent application Ser. No. 11/627,721 filed Jan. 26, 2007, which is a continuation of U.S. application Ser. No. 10/445,212 filed May 23, 2003, now abandoned, which is a continuation-in-part of U.S. application Ser. No. 10/385,013 filed Mar. 10, 2003, now abandoned, which is a 371 of German application Serial No. 10242998.7 filed Sep. 17, 2002, all of which are hereby incorporated by reference herein.  
     
    
     FIELD OF THE INVENTION  
       [0002]     The invention relates to a cushion of paper, and to a method and an apparatus for producing it.  
       BACKGROUND OF THE INVENTION  
       [0003]     In packing various items, many kinds of cushions for filling voids are known, which are produced from paper web by crumpling. They are based on folding or rolling the edges of a paper web inwardly and then crumpling the folded or rolled paper web. From this continuously created web, individual cushion portions are then cut off to a desired length.  
         [0004]     The object of the present invention is to create a paper cushion which has improved cushioning properties and is less expensive. Improved cushioning properties means that the product has higher resiliency and/or elasticity, or in other words provides better cushioning of items packed, in proportion to the quantity of paper used. A cushioning product is less expensive if less paper is required to fill a given volume, for example on the basis of the way in which the cushioning product is shaped.  
       SUMMARY OF THE INVENTION  
       [0005]     One such product is characterized according to the invention in that the cushion is a crumpled paper tube. A paper tube, in the opened-out state, is upset and thereby crumpled. In comparison with previous products, more air is “trapped” inside this crumpled tube. The circular cross-section disposition of the paper leads to improved properties in cushioning and padding packed items.  
         [0006]     These properties are improved still further by preferably providing that the paper tube is crumpled in the longitudinal direction and in the radial direction.  
         [0007]     The cushioning properties are furthermore improved if the paper tube is provided in the longitudinal direction with a strip of paper or adhesive. This is expediently effected by providing that this strip and/or this adhesive is formed when a paper tube is produced from a paper web by folding or rolling in the edges and joining them together.  
         [0008]     It is especially advantageous to use kraft paper, which is already intrinsically especially stable.  
         [0009]     For producing such a cushion, it is expedient beforehand to “configure” a paper tube, that is, to prepare it, specifically by providing that one or more paper webs are joined together along their edges, for instance by directly adhesively bonding overlapping regions or by gluing strips on. These paper tube webs are then processed further to form the cushions or cushion portions in the apparatuses suitable for that purpose.  
         [0010]     A paper tube web prepared and put together in this way can as a result be made smaller, or in other words narrower, by providing that along the two outer sides of the paper tube, in the flatly put-together state, indented folds are provided. Thus in a small space, more paper can be furnished and transported to the places where the paper tube web is processed further.  
         [0011]     The paper tube web is preferably provided with intended tearing points at prepared, standardized intervals. These are points which tear when tension is exerted, as a consequence of the weakening of the material brought about by them. In other words, if tension is exerted on the paper tube web, it tears at the points where it is “supposed to” tear as intended. These points are preferably formed by a perforation and/or by certain notches or recesses.  
         [0012]     The method for producing the cushion and the apparatus suitable for it are embodied such that the paper tube is slipped onto a core, which distributed over its circumference has rollers (inner rollers) that cooperate with rollers disposed outside the core (outer rollers), at least some of which are driven, and that thus draw in the paper tube, pass it between them, and crumple it. This is preferably accomplished by providing that two groups of rollers, spaced apart from one another in the longitudinal direction, are provided, which are driven at different circumferential speeds, so that between the two groups of rollers, crumpling by way of creasing of the paper material comprising the paper tube web occurs, and this creasing is crumpled further upon the passage through the second group of rollers.  
         [0013]     This can be improved still further by providing that within the second-named group of rollers, further rollers are provided, which are disposed on a smaller boundary circle, so that the already-crumpled paper tube is also pushed together in the radial direction and crumpled anew on passing through the last-named rollers.  
         [0014]     An apparatus for producing a cushion of paper comprises the provision of feeder means for the paper tube web that slip it onto a core and the provision of crumpling means, which crumple the paper tube web that has been opened out by being slipped onto the core. The feeder means are formed by rollers disposed in a first plane transverse to the feeding direction, which are provided both on the core (“inner rollers”) and outside the core (“outer rollers”) in the apparatus; all of these rollers initially continuously open out the paper tube once it has been inserted and then slip it onto the core. In further planes extending perpendicular to the transport direction of the paper tube web, further groups of rollers can be provided. They then, as already described, accomplish the crumpling in that first a circumferential creasing occurs by virtue of longitudinal compression, and then a radial compacting occurs by virtue of radial compression ensues.  
         [0015]     Exemplary embodiments of the invention and advantageous refinements of them will be described below. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS OF THE INVENTION  
       [0016]      FIG. 1 , an exemplary embodiment of a cushion;  
         [0017]      FIG. 2 , an exemplary embodiment of a paper tube from which by crumpling a cushion is created;  
         [0018]     FIGS.  3 ( a ) through ( f ), various schematic illustrations of cross sections of a paper tube;  
         [0019]      FIG. 4 , the schematic illustration of a paper web processing unit for producing a cushion;  
         [0020]      FIG. 4   a,  the location of the axes of the rollers  16 ,  20 ,  21  relative to one another;  
         [0021]      FIG. 5 , a plan view on a paper tube web;  
         [0022]      FIG. 6 , a schematic illustration of a stand with a paper processing unit, as an apparatus for producing cushions;  
         [0023]      FIG. 7 , in perspective, a further exemplary embodiment of an apparatus for producing a cushion from a paper tube web;  
         [0024]      FIG. 8 , part of the apparatus of  FIG. 7 ;  
         [0025]      FIG. 8   a,  a schematic illustration of the drive of the rollers in  FIG. 7 ;  
         [0026]      FIG. 9 , a cross section taken along the arrows IX-IX in  FIG. 7 ;  
         [0027]      FIG. 10 , a side view of the apparatus of  FIG. 7 ;  
         [0028]      FIG. 11 , a plan view of the apparatus of  FIG. 7 ;  
         [0029]      FIG. 12 , a cross section taken along ling  12 - 12  through the apparatus of  FIG. 7 ;  
         [0030]      FIG. 13 , a perspective view of the core;  
         [0031]      FIG. 14 , a side of the core of  FIG. 13 ;  
         [0032]      FIG. 15 , a cross section taken along line  15 - 15  through the core of  FIG. 13 ;  
         [0033]      FIG. 16 , a second exemplary embodiment (modular construction);  
         [0034]      FIG. 17 , the exemplary embodiment of  FIG. 16 , with half of the frame and the core removed;  
         [0035]      FIG. 18 , the exemplary embodiment of  FIG. 16 , with the core inserted and the entire frame removed;  
         [0036]      FIG. 19 , a section through the exemplary embodiment of  FIG. 16 ;  
         [0037]      FIG. 20 , a section taken in the direction of the arrows XX-XX in  FIG. 19 ;  
         [0038]      FIG. 21 , a section taken in the direction of the arrows XXI-XXI in  FIG. 19 ;  
         [0039]      FIG. 22 , a section taken in the direction of the arrows XXII-XXII in  FIG. 19 ;  
         [0040]      FIG. 23 , a schematic drive diagram for the outer rollers in the exemplary embodiment of  FIGS. 16-22 ;  
         [0041]      FIG. 24 , a brake;  
         [0042]      FIG. 25 , a slip coupling;  
         [0043]      FIG. 26 , a side view of the apparatus of  FIG. 16 . 
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0044]      FIG. 1  shows a crumpled cushion, or a crumpled cushion portion  1 , having the length (in the crumpled state) a=approximately 28 cm, the inside diameter b=approximately 7 cm, and the outer diameter c=approximately 14 cm. It is understood that these figures are intended solely for purposes of illustration and are not to be understood as limiting. The cushion portion  1  is created by crumpling a prefabricated (configured) paper tube  2 , specifically in the form of upsetting in the longitudinal direction (axial direction) with ensuing compression. One such paper tube  2  is shown in perspective in slightly opened form in  FIG. 2 , in terms of the cross section of  FIG. 3 ( a ). It involves a paper web  6 , which is folded as shown, that is, with two lateral indented folds  2 ′. The folded paper web has a portion  3 , at which the two edges  4 ′,  4 ″ overlap and are glued to one another by means of an adhesive layer  7 . Other possible cross sections of the paper tube  2  are shown in FIGS.  3 ( b ), ( c ), ( d ), and ( e ), and in  FIG. 3 ( c ), ( d ), ( e ), strips  5  are shown with which the edges of the folded paper web  6 , or of two parallel paper webs  6 ′,  6 ″ are joined or glued together. In this prepared form, the term used is also a configured paper web, or a paper tube web  8 .  FIG. 3 ( f ) illustrates another possible cross section of paper tube  2  wherein two parallel paper webs  6 ′,  6 ″ are joined or glued together via adhesive layers  7 ,  7  between their confronting lateral edges.  
         [0045]     The paper is preferably so-called “kraft paper”, that is, very firm, brown packing paper made of unbleached sulfate cellulose, usually using very long fibers, which is therefore especially tear-resistant. It is understood that this statement should again be understood only as an example. The webs are glued together, as already mentioned. The adhesive layers  7  that are striplike in the longitudinal direction of the cushion portion form, optionally together with the strip  5 , an additional reinforcement of the cushion, which enhances the cushioning properties.  
         [0046]      FIG. 4  shows one basic embodiment of a paper processing unit  35  for creating a cushion  1 . A roll  11  is seated on a shaft  10 . The roll is formed by a configured, wound-up paper tube web  8 . This tube is drawn onto a core  15  by two pairs of driven rollers  16  and kept on hand there. One pair of rollers  16  can be seen; a further pair is located perpendicularly before and behind the plane of  FIG. 4 , in the same vertical plane. The rollers  16  are followed by rollers  17 , which are driven at a somewhat lower speed, so that between the two creasing  8 ′ ensues from upsetting, and upon passage through the paper tube web  8  between the rollers  17  and the core, this creasing undergoes crumpling. Two further rollers  17  are disposed in the same vertical plane, in  FIG. 4  in front of and behind the core  15 , with their axes perpendicular to those of the rollers  17  shown. Pairs of rollers  20 ,  21 ,  22 ,  23 ,  24  that freely travel jointly are disposed on the core  15  and serve to provide for low-friction travel along the paper tube on the outside of the core. As shown in  FIG. 4   a,  the rollers  16  plunge by an amount h (plunging depth) between the rollers  20 ,  21 , so that they secure the core  15 , in a defined position, against axial displacement.  
         [0047]     One possibility for cutting off individual cushion portions from the continuously manufactured band is seen in  FIG. 5 . Once again, a paper tube web  8  is shown in plan view that has perforation lines  12 , or tearing points or lines of separation, at intervals of 80 cm, for instance. Along these lines, for instance at the spacing of half the width of the paper tube web, rhomboid cutouts  13  are provided. If the rollers  16  are now stopped at predetermined time intervals, which correspond to the processing of a particular longitudinal portion, and the rollers  17  are allowed to continue to rotate, then along the perforated line that is then located between the rollers  16  and  17 , one cushion portion  1  is torn off. The tearing off can also be done by other means in the transport direction T, before or after the apparatus shown. Separating the cushion portions can naturally also be done by a cutting device or other separating devices as well.  
         [0048]     One simple design of a stand with a paper processing unit  35  for producing such a cushion portion is shown in  FIG. 6 .  
         [0049]     The stand for the various components comprises a bottom plate and scaffold  31 , which has rolls  32  and  33  onto which configured paper tube webs  8  are wound. The upper roll  32  is the one from which a paper tube web  8  is just now being drawn off and processed. Roll  33  is a reserve roll. On the upper end of the scaffold  31 , by means of rail  37 , slot  36  and locking screw  39 , the processing unit  35  is disposed so as to be adjustable in height. The equipment can move from place to place by means of rollers  38 . The mounting of the two rolls  32  and  33  is done without shafts on further rolls (not shown.  
         [0050]      FIGS. 7-12  show one exemplary embodiment of an apparatus for producing a cushion portion  1  in more detail.  
         [0051]     In  FIG. 7 , a stand  40  can be seen, on the right-hand side of which two rollers  41  and  42  are provided, on which a roll  11  of a paper tube web  8  is disposed without a shaft.  
         [0052]     As best seen from  FIG. 8 , outside the core  15  and therefore hereinafter also known as “outer rollers”, four upper rolls  43 ,  44 ,  45 ,  46  and pairs of associated lower rollers  43 ′,  44 ′,  45 ′,  46 ′ can be seen. Transversely to this, but with axes in the same vertical plane and also facing one another in pairs, further pairs of rollers  61 ,  61 ′,  62 ,  62 ′,  63 ,  63 ′,  64 ,  64 ′ are provided (see also  FIG. 11 ). These pairs of rollers cooperate with rollers that rotate freely on the core  15 , namely the pair of rollers  51 ,  51 ′, the pair  52 ,  52 ′, the two pairs of rollers  53 ,  53 ′ and  54 ,  54 ′, and the pair  55 ,  55 ′. Among the “inner rollers” there are also further pairs, which are disposed with their axes perpendicular to the axes of the aforementioned rollers, but in the same vertical plane (in this exemplary embodiment), that is, the pairs of rollers  71 ,  71 ′,  72 ,  72 ′,  73 ,  73 ′,  74 ,  74 ′,  75 ,  75 ′ (see also  FIGS. 12 and 14 ).  
         [0053]     The cooperation of only one of the outer pairs of rollers, namely of the outer pairs of rollers  45 ,  45 ′ and  63 ,  63 ′ with each of the two pairs of rollers  53 ,  53 ′ and  54 ,  54 ′ spaced apart from one another on the core  15 , secures the core  15  against an axial displacement, despite its being freely supported; in this respect, see also the explanation above for  FIG. 4   a.  Since the outer rollers are driven and are in engagement with the inner rollers, the paper tube web  8  is thus drawn through between the outer and inner rollers and, as a consequence of different drive speeds of the outer rollers, is folded between them and then crumpled.  
         [0054]     The drawing in of the paper tube web is effected by the two pairs of rollers  61 ,  61 ′ and  43 ,  43 ′ facing one another, while the emergence of the upset roll is effected by the pairs of rollers  64 ,  64 ′ and  46 ,  46 ′.  
         [0055]     For driving the “outer roller”, a central electrical drive motor  80  is provided, to which a gear  81  for stepping down the rotary speed is flanged. The power takeoff shaft  82  is connected to the gear  83 , which in turn first drives the shaft  84 , deflected by 90°, and second drives the shaft  85 , which in turn, deflected by 90° in the gear  83 ′, drives the shaft  99 . The gear wheels  90  and  91  are seated on the shaft  84 . The gear wheel  90  drives the gear wheel  92  on the shaft  93  via a chain  220  and gear wheel  91  and drives the gear wheel  94  on the shaft  95  via chain  221 . The shaft  95  extends from the top inward into the gear  96 , which deflected by 90° drives the shaft  97 , which extends into the gear  98 , which deflected by 90° drives the shaft  86  and thus the roller  63 ′. Also seated on the shaft  95  is a gear wheel  100 , which via a chain  222  drives the gear wheel  101  and thus the shaft  102 , on which the roller  64  is seated. The shaft  99  likewise drives a gear wheel  103  (see  FIG. 8   a ), which via a chain  223  drives the gear wheel  107  and thus the shaft  108  and thus also the roller  61 ′. The rollers disposed perpendicularly move freely in part. The roller  44  on shaft  109 ′ is coupled to the shaft  84  via a bevel gear connection  109 . It is understood that pulleys may be used instead of the chains. In this way, it is possible to make do with only one motor.  
         [0056]     By means of different gear ratios from the shaft  82  to the shaft  85  on the one hand (gear  83 ) and shaft  84  to shaft  95  on the other (gear wheels  91 ,  94 ), it is attained that the rollers  61 ,  61 ′,  62 ,  62 ′ located in the vicinity of the drawing-in region, that is, to the right in  FIG. 8 , travel somewhat faster than the rollers  63 ,  63 ′,  64 ,  64 ′ downstream of them in the transport direction, so that the aforementioned creasing  8 ′ can occur.  
         [0057]     Groups of rollers are described herein. In the exemplary embodiment of  FIGS. 1-5 , the first group is formed by those rollers whose axes are located (see  FIG. 12 ) in the vertical planes A and B (in terms of the exemplary embodiment of  FIGS. 8-12 , that is, perpendicular to the transport direction T of the paper tube). The second group of rollers is formed by those rollers that are located in the vertical planes C. The third group forms the rollers in the plane D.  
                                                       On the apparatus               On the core 15:   outside the core 15:       Group   Vertical Plane   “Inner Rollers”   “Outer Rollers”                   First   A   51, 75, 51′, 75′   43, 61, 43′, 61′           B   52, 74, 52′, 74′   44, 62, 44′, 62′       Second   C   53/54, 72/73,   45, 63, 45′, 63′               53′/54′, 72′/73′       Third   D   55, 71, 55′, 71′   46, 64, 46′, 64′                  
 
         [0058]     Each two inner rollers (such as  53 / 54 ) that are associated with an outer roller (such as  51 ) and are associated with one another by the symbol “/” have a certain spacing from the plane C shown in  FIG. 12 , but this spacing is not critical in the present situation. They cooperate with a third roller and serve to fix the core  15  in the axial direction (see the explanation above for  FIG. 4   a ).  
         [0059]     The rollers of the first group travel at a “first” circumferential speed, and the rollers of the second group travel at a “second” circumferential speed that is less than the first circumferential speed. The result is a crease (see  8 ′ in  FIG. 4 ), which upon passage through the second group is also crumpled.  
         [0060]     Upon passage through the rollers of the third group in plane D, crumpling occurs again, specifically as a consequence of the lesser diameter of the core  15  at this point, including in the radial direction. This radial decrease in diameter takes place at the transition of the paper tube from the portion  200  to the portion  201  (see  FIG. 13 ). The term “diameter” is not meant to be understood strictly here but instead pertains to the approximate outline around the plates  130 ,  131 ,  150 ,  151  at the applicable point. Accordingly, compressive crumpling of the paper tube takes place in the axial direction and in the radial direction, the latter taking place in/after the diameter reduction of the core and thus of the paper tube.  
         [0061]     In  FIGS. 13-15 , the construction of the core  15  in detail.  
         [0062]     As seen in  FIG. 13  and  FIG. 14 , the core  15  is constructed of two parts, namely a front part  120  in terms of the transport direction and a rear part  121  in terms of the transport direction. The dividing line is marked  120 ′. The two parts are joined together, in this specific case in that the front part has a connecting element  125 , which is connected on the one hand to the front part  120  by means of the screw  126  and on the other to the rear part  121  by means of the screw  127 .  
         [0063]     If the two parts are viewed together in the assembled state (see  FIG. 14 ), it can be seen that the core  15  substantially comprises an upper plate  130  and a lower plate  131 , which are joined to one another, via spacers  140 ,  141 ,  142  that are disposed between them, by means of screws  145 . The rollers  71 ′- 75 ′ (and behind them and therefore not visible, the rollers  71 - 75 ) are then disposed between the plates.  
         [0064]     Both on the upper plate  130  and on the lower plate  131 , two further plates  150 ,  151  each are disposed continuously (but in two parts, corresponding to the front part  120  and the rear part  121 ), these further plates being parallel and perpendicular to the plates  130 ,  131 ; these further plates serve to support the rollers  51 - 54 , that is, on the underside  51 ′ - 55 ′.  
         [0065]      FIG. 16  shows a further exemplary embodiment of modular construction, in which all the rollers are disposed inside a boxlike frame  230 , which comprises two frame portions  231  and  232 , bent at right angles, which are screwed to another by means of the angle brackets  233 . The shaft  234  protrudes from the frame  230  at the bottom. It corresponds to the shaft  84  in  FIG. 8  and  FIG. 8   a  and is connected to a drive motor, not shown in  FIG. 16 . Within the module, the core is also fixed in the axial direction between the rollers. A guide baffle  236  that is adjustable by means of screws is disposed on the frame, and the paper tube web  8  can be delivered via its guide face  237 . The paper tube web is drawn across the mushroom-shaped inlet head  238  and opened out in the process and pulled through between the rollers.  
         [0066]     As seen from  FIGS. 20 and 23 , the shaft  234  carries the outer roller  241  and, via the two bevel gears  301  and  302 , drives the shaft  303  and thus also the roller  251 . The shaft  303 , via the bevel gears  304 ,  305 , then drives the shaft  306  and thus also the roller  241 ′. The shaft  234  moreover, via the bevel gear  307  and the bevel gear  308 , drives the shaft  309 , on which the roller  251  is seated. The rollers  241 ,  241 ′,  251 ,  251 ′ cooperate in such a manner with rollers  261 ,  261 ′,  262 ,  262 ′,  271 ,  271 ′,  272 ,  272 ′, disposed freely rotatably on the internal tube  310 , which is part of the core  235 , that when the shaft  234  is driven, a paper tube web  8  is pulled through, between the outer rollers and the inner rollers. The rollers  261 ,  261 ′,  271 ,  271 ′ are seated perpendicular to the plane of  FIG. 20  just before the rollers  262 ,  262 ′,  271 ,  271 ′ (see  FIG. 19  and  FIG. 26 ). The two “inner rollers” disposed in pairs before and behind the plane in  FIG. 20  cooperate with the “outer rollers” in order to axially fix the core.  
         [0067]     Seated on the shaft  303  ( FIG. 20 ) on one side (to the right) of the roller  251  is the gear wheel  311 , and on the other is the gear wheel  312 .  
         [0068]     The gear wheel  311 , via a chain or pulley (not shown), drives the gear wheel  313  on the shaft  314  (see  FIG. 21 ). The shaft  314  carries the bevel gears  315  and  316 , which via the bevel gears  317  and  318  drive the shafts  319  and  320 . In this way, the rollers  240 ,  240 ′,  250 ,  250 ′ seated on these shafts are driven, and in turn cooperate with the rollers  260 ,  260 ′,  270 ,  270 ′ in such a way that between a paper tube web  8  can be drawn in and pulled through.  
         [0069]     The gear wheel  312  ( FIG. 20 ), via a chain or a pulley (not shown), drives the gear wheel  325  (see  FIG. 22 ), on which the shaft  326  that carries the roller  252  is seated. Via the bevel gears  327 ,  328 ,  329 ,  330 , the shaft  326  drives the shafts  331  and  331 ′ and thus the rollers  242 ,  242 ′ seated on them. Seated on the lower end of the shaft  331  is a bevel gear  332 , which drives a bevel gear  333 . The latter drives the shaft  334  and thus the roller  252 ′.  
         [0070]     In this exemplary embodiment, the rollers  242 ,  242 ′,  252 ,  252 ′ (“outer rollers”) are not assigned any corresponding rollers, cooperating with them, on the core or on the internal tube  310 . To bring about the crumpling of the tube passing between these rollers on the one hand and the internal tube  310  on the other and already crumpled and now radially compressed, and to improve this crumpling and at the same time to reinforce the feeding of the tube in the transport direction T, the rollers  242 ,  242 ′,  252 ,  252 ′ have pins  335  distributed at regular intervals along their circumference.  
         [0071]     The shafts are each in bearings  359  that are provided in gibs  350 - 357  (see  FIG. 17 ). The gibs are screwed to the frame portions  231  and  232 , for example by means of the screws  358  (see  FIG. 16 ).  
         [0072]     Thus a paper web tube  8  is drawn manually onto the core  235  in the transport direction T at the beginning of the procedure, placed between the rollers  250 ,  250 ′,  240 ,  240 ′ (outer rollers) and the rollers  260 ,  260 ′,  270 ,  270 ′ (inner rollers), and as soon as these rollers engage it, it is drawn by them continuously between them and pulled through between them, because of the fact that the outer rollers are driven as described. Next, they are pulled through between the rollers  251 ,  251 ′,  241 ,  241 ′ (outer rollers) and the rollers  261 ,  261 ′,  262 ,  262 ′,  271 ,  271 ′,  272 ,  272 ′ (inner rollers), but at a lower speed. Accordingly what occurs between these two groups of rollers is a creasing, which is not shown in these drawings, but can be seen in  FIG. 4  (at  8   a ). The first group is formed by the outer rollers  240 ,  240 ′,  250 ,  250 ′ and the inner rollers  260 ,  260 ′,  270 ,  270 ′. The second group is formed by the outer rollers  241 ,  241 ′,  251 ,  251 ′ and the inner rollers  261 ,  261 ′,  262 ,  262 ′,  271 ,  271 ′,  272 ,  272 ′. To make it possible for the creasing to occur, however, the diameter of the paper web tube must be correspondingly greater than that of the core.  
         [0073]     The different speeds of the first and second groups of rollers is due to the fact that the gear ratio of the gear wheel  311  ( FIG. 20 ) to the gear wheel  313  is designed accordingly.  
         [0074]     A further crumpling then takes place upon the reduction in the radial spacing (relative to the center line of the internal tube  310 ) of the paper web tube as it is transported from this second group of rollers to the third group of rollers, formed by the rollers  242 ,  242 ′,  252 ,  252 ′. These are “outer rollers”. This exemplary embodiment does not have any “inner rollers” corresponding to outer rollers  242 ,  242 ′,  252 ,  252 ′. Nevertheless, further crumpling occurs. The speed of revolution of this third group of rollers is determined by the gear ratio of gear wheel  312  ( FIG. 20 ) to gear wheel  325  ( FIG. 22 ).  
         [0075]     It should furthermore be noted that the inner rollers are supported on the internal tube  310  because suitably U-shaped bearing brackets  360  are screwed onto the internal tube ( FIGS. 20, 21 ).  
         [0076]     To brake outer rollers of the first group of rollers, or—more precisely—the driven outer rollers  240 ,  240 ′,  250 ,  250 ′ (see  FIG. 21 ), in order to bring about tearing off of the paper web tube at the “intended tearing points”  9 / 9 ′ (see  FIG. 5 ), the following provisions are made: A brake wheel  361 , fixed in a groove  363  by a tongue  362 , is disposed on the shaft  320  ( FIG. 21 ). The brake wheel  361  can, as seen from  FIG. 24 , be brought to a standstill by a brake belt  365 , when the electric motor  366  is excited. Then the armature  367 , on which the retaining rod  368  is secured with the brake belt  365 , is drawn inward by approximately 2 mm in the direction of the arrow. This tenses the brake belt  365  and stops the motion of the shaft  320 . As a consequence of the geared connection via bevel gears and shafts, this stop then causes a corresponding stop of the outer rollers  240 ,  240 ′,  250 ,  250 ′ shown in  FIG. 21 .  
         [0077]     So that despite the aforementioned stop, the driven rollers  241 ,  241 ′,  251 ,  251 ′ ( FIG. 20 ) can continue to rotate, the gear wheel  313  ( FIG. 21 ), which is driven by shaft  303  via the gear wheel  311  and pulleys, is supported on the shaft  314  by means of a slip coupling  370 , which is shown in further detail in  FIG. 25 . This slip coupling makes it possible for the second group of rollers to continue rotating while the first group is stopped. The paper web tube then tears.  
         [0078]     The slip coupling functions as follows: The roller  250  is supported on the shaft  314  in the groove  369  by means of the tongue  369 ′. The gear wheel  313  rests laterally on the roller  250  but is not solidly connected to it. Inside the gear wheel  313 , there is a further gear wheel  371 , whose left-hand shoulder  371 ′ is seated on an associated shoulder face  313 ′ of the gear wheel  313 . The gear wheel  371  is coupled in the direction of rotation to the shaft  314  by the tongue  372  also engaging the groove  369  and is pressed from right to left (in  FIG. 25 ) into contact against the gear wheel  313 . An adjusting screw  374  is screwed into a recess  373 , provided with a female thread  373 ′, in the gear wheel  371 . The adjusting screw, with its outer shoulder  374 ′, presses against the cup spring  375 , which in turn, with its outer leg  375 ′ bent over inward, exerts pressure on the gear wheel  313 . The adjusting screw  373  is fixed in the axial direction because it is screwed onto a male thread of the tubule  376 , which is disposed fixedly on the shaft  374  by means of a pin  377 . In other words, the farther the adjusting screw  374  is screwed inward (to the left in  FIG. 25 ), the harder the cup spring  375  with its leg  375  presses on the end face of the gear wheel  313 . As a result, the shaft  314  is coupled frictionally to the gear wheel  313 . However, the coupling is dimensioned such that whenever—as described—the shaft  314  is brought to a stop, the gear wheel  313 , overcoming this friction, can rotate further. The adjusting screw  374  can be adjusted from outside by the engagement of a suitable pin with one of the transverse bores  378 .  
         [0079]     The braking device, comprising electromagnet  366  and brake belt  365 , is connected to a support plate  380 , which is screwed to the frame portion  232  (see  FIG. 26 ).