BACKGROUND OF THE INVENTION 
     The invention relates to a method of cleaning packaging machines, in particular cigarette packaging machines, which have conveying devices, folding subassemblies, in particular folding turrets, pack dryers, in particular drying turrets, and other devices, it being the case that pack contents—cigarette group—and blanks of packaging material run through the packaging machine for the purpose of producing packs. The invention also relates to a packaging machine and cleaning devices. 
     In the case of high-capacity packaging machines, in particular cigarette packaging machines, the cleaning which is necessary poses a particular problem. Stoppage times of the packaging machine result in considerable reductions in production. Added to this is the fact that, for many subassemblies, devices, etc. of the complex packaging machine, (manual) cleaning cannot be carried out sufficiently, if at all. 
     SUMMARY OF THE INVENTION 
     The object of the invention is to propose measures for effective cleaning of a packaging machine without adversely affecting the operating sequences to any great extent. 
     In order to achieve this object, it is proposed according to the invention that, instead of the pack contents—cigarette group—and/or the packaging material, cleaning devices or cleaning elements be conveyed through the packaging machine. 
     The invention is based on the finding that contaminants occur, in particular, in those regions and/or on those devices which are in contact with the packs, the pack contents or the packaging material during production of the packs. The solution to the problem according to the invention thus makes provision to convey through the packaging machine devices, elements or bodies which are dimensioned a manner corresponding to a pack, the pack contents or packaging material. The relevant cleaning devices thus come into contact with the machine devices and elements which are involved in the process for producing the packs. On account of appropriate configuration or pre-treatment of the cleaning elements, the relevant machine parts are automatically cleaned as a result of the cleaning elements running through. 
     In the case of cigarette packaging machines, the cleaning bodies or elements may be cuboidal bodies of the dimensions of a cigarette block (cigarette group wrapped in an inner blank) or of a cigarette pack. Furthermore, according to the invention, it is possible for blanks of paper or paper-like materials with cleaning properties to be directed through the packaging machine, to be precise in particular together with the (cuboidal) cleaning bodies. These are treated, within the packaging machine, in the same way as the packs or the packaging material, the one exception being constituted by any glue subassemblies, which are brought to a standstill during this cleaning phase. 
     According to a further proposal of the invention, the packaging machines themselves are geared towards the cleaning process, for example by virtue of the installation of subassemblies for treating the cleaning material or the cleaning bodies. For example, it is possible for the latter, as they are being fed to a folding turret, to be impregnated or coated with an active cleaning agent. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     Further details of the invention are explained in more detail hereinbelow with reference to the drawings, in which: 
     FIG. 1 shows a vastly simplified side view of a cigarette packaging machine, 
     FIG. 2 shows a perspective illustration of a cleaning body in the packaged state, 
     FIG. 3 shows a cross section of FIG. 2 along section plane III—III, 
     FIG. 4 shows a plan view of another cleaning body, 
     FIG. 5 shows an end view of the cleaning body according to FIG. 4, 
     FIG. 6 shows a detail of a turret, namely of a drying turret of a cigarette packaging machine, partially in radial section, 
     FIG. 7 shows the detail of the drying turret in a radially directed view in accordance with arrow VII of FIG. 6, 
     FIG. 8 shows, on an enlarged scale, a side view of a detail of a folding turret of the packaging machine according to FIG. 1, 
     FIG. 9 shows a simplified side view of a further detail of a packaging machine, namely a web connector. 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     FIG. 1 shows, as an advantageous exemplary embodiment, a schematic overview of a cigarette packaging machine for producing cigarette packs of the soft-carton type. The packaging machine is described in detail in U.S. Pat. No. 4,750,607. According to this document, the packaging machine comprises a central folding turret  10  to which cigarette groups are fed by a pocket conveyor  12 . In the region of a charging station  13 , the cigarette groups  11  are axially pushed out of a cigarette magazine and into pockets  14  of the pocket conveyor  12 , said pockets being open at both ends. Details of the configuration of the pocket conveyor  12  can be gathered from U.S. Pat. No. 4,735,032. 
     The folding turret  10  has a multiplicity of circumferentially spaced-apart hollow bodies, namely so-called folding mandrels  15 . Blanks of a cigarette pack which is to be produced are folded on the outside of said folding mandrels, namely, in the region of a first blank station  16 , an inner wrapper made of paper or tin foil and, in the region of a second blank station  17 , blanks of paper or similar material for forming the outer packaging, that is to say a soft carton. The cigarette group is introduced into the folding mandrels  15 , which are open at both ends, in an axis-parallel direction in relation to the folding turret  10 . Once the blanks have been folded on the outside of the folding mandrels  15 , the cigarette group, together with the (folded) blanks, is pushed out of the folding mandrel  15  and/or away from the same. 
     Further on, the cigarette pack is completed by final folding steps and then transferred to a drying subassembly via a transfer turret  18 , for example of the design according to EP 0 761 539. Said drying subassembly is a drying turret  19 , expediently of the design according to U.S. Pat. No. 5,544,467. 
     In the region of the drying turret  19 , it is intended to harden areas of glue of the cigarette pack in the region of the soft carton. Moreover, the (cuboidal) configuration of the cigarette pack is stabilized. For this purpose the folding turret comprises a plurality of axis-parallel drying shafts  20  which are arranged along the circumference and are in the cross-sectional shape of a cigarette pack. A plurality of, in the present case three, cigarette packs are arranged right up against one another in the longitudinal direction in the drying shaft  20 . By virtue of a following cigarette pack being pushed in, a treated cigarette pack is pushed out on the opposite side. The cigarette packs passing out of the drying turret  19  are transported away via further conveying devices  21 . 
     In order to clean a packaging machine designed, for example, in the manner described, cleaning elements and/or cleaning bodies are directed through the packaging machine instead of the cigarette groups and of the packaging material, that is to say blanks. The contact and the necessary movement of the cleaning elements and bodies relative to the devices or surfaces of the packaging machine bring about the cleaning, to be precise in particular by mechanical action (sliding, brushing) or by the action of suitable cleaning agents adhering to the cleaning bodies. 
     FIGS. 2 and 3 show, as an example, a cleaning body  22  which is of the dimensions of a cigarette pack or of a cigarette group wrapped in an inner blank, that is to say of the dimensions of a cigarette block. The cleaning body  22  consists of a compliant material, with the result that the compliance of the material means that the packaging machine is not damaged in the case of defects or catching. Accordingly, the cleaning body comprises a core  23  made of (rigid) foam, foam rubber or the like. The core  23  is encased by a possibly multi-layer covering  24 . The latter consists of a nonwoven, felt or a so-called tissue material. The covering  24  is expediently impregnated or coated with a suitable cleaning agent. 
     The cleaning body  22  which has been prepared or pretreated for the cleaning process is provided in sealed packaging, in the present case in a foil-material tubular bag  25 . This means that the cleaning body  22 , possibly provided with cleaning agents, can be stored without the cleaning action being reduced. For use, the cleaning body  22  is removed from the tubular bag  25 . 
     Another possible embodiment of a cleaning body  22  is shown in FIGS. 4 and 5. This cleaning body is a cuboidal block  26  which has mechanical cleaning means, namely brushes  28 , on the outside, in the present case on small end surfaces  27 . These brushes are positioned such that they act in a cleaning manner on lateral, fixed guide surfaces of the packaging machine. 
     Once the packaging machine has emptied, that is to say for example during a necessary interruption in operation, with a change in the type of pack which is to be produced, etc., the cleaning bodies  22  designed in the manner described above, or in some other manner, are introduced into the packaging machine for the purpose of carrying out the cleaning. According to FIG. 1, in the region of the charging station  13 , the cleaning bodies  22  are introduced into the pocket conveyor  12  or into the pockets  14  instead of cigarette groups. The functional sequences of the packaging machine during the production of cigarette packs are taken into account here. For this reason, four cleaning bodies  22  are introduced into pockets  14  in each case. The rest of the pockets  14  remain empty. 
     In the same way as cigarette groups  11 , the cleaning bodies  22  are fed to the folding turret  10  and transferred to the same. In this case, the cleaning bodies  22  are pushed into the folding mandrels  15  and out of the same again in accordance with the functional sequence. Furthermore, the cleaning bodies  22  are fed to the drying turret  19  via the transfer turret  18  and pushed through the drying shafts  20 . 
     The cleaning method is implemented here such that a plurality of cleaning phases are used for the purpose of cleaning the entire drying turret  19 . The operation of charging with cleaning bodies  22  is selected here such that one after the other four circumferentially adjacent drying shafts  20  are charged in their entirety with (in each case three) cleaning bodies  22 . For this purpose, in each case groups of four cleaning bodies  22  can be introduced, in the region of the charging station  13 , at such distances apart from one another that the respectively four cleaning bodies are distributed one after the other to the same drying shafts  20  of the drying turret  19  (FIGS.  6  and  7 ). The drying shafts  20  are cleaned over their entire length by the sliding movement of the cleaning bodies  22  pushed through them, that is to say shaft walls  29 ,  30 ,  31 ,  32  in particular are cleaned. Furthermore, lateral guide walls  33 ,  34  of the drying turret  19  are also cleaned by virtue of end surfaces of the cleaning bodies  22  sliding past them. 
     In order to achieve an additional cleaning effect or to include other devices of the packaging machine, it is provided that in addition, or as an alternative, cleaning blanks  35 —instead of blanks of packaging material—are directed through the packaging machine. The cleaning blanks  35  are designed and/or pretreated so as to achieve a cleaning effect, in particular by being impregnated or coated with a cleaning agent. 
     In the case of the present exemplary embodiment, the cleaning blanks  35  are fed via the blank stations  16 ,  17 , in the present case by way of the blank station  17 . The cleaning blanks  35  are severed from a continuous material web  36  and transferred to the folding turret  10  or a folding mandrel  15  via a feed roller  37 . The cleaning blanks  35  are fed by the same devices which also transfer the packaging blanks, that is to say for example by a transfer device  38  of the design according to EP 0 839 719. In this case, the cleaning blank  35  is positioned on the outside of the folding mandrel  15  and folded around the latter. A cleaning body  22  is expediently located within the folding mandrel  15 . In the same way as a cigarette pack, the cleaning body  22  is pushed out of the folding mandrel  15  at the envisaged position, the cleaning blank  35  provided on the outside of the folding mandrel  15  being carried along in the process. For carrying-along purposes, said cleaning blank is folded, but not glued, in the region of a side corresponding to a base wall of the cigarette pack. In this case, the cleaning blank  35  also runs through the drying turret  19  together with the cleaning body  22 . 
     Preparation of the cleaning blank  35  for the cleaning operation, that is to say in particular coating or impregnation with a cleaning agent, takes place in the region of the blank station  17 . A container  39  with a suitable cleaning fluid is provided for this purpose. A removal device, namely a removal roller  40 , removes a layer of the cleaning agent from the container  39  and transfers it, by contact, to the outside of the cleaning blank  35 . In the present case, the removal roller  40  is assigned to the feed roller  37 , with the result that the coating or impregnation is carried out immediately before the cleaning blank  35  is introduced into the packaging machine. 
     The packaging machine is expediently assigned a web-connection subassembly, namely a splicing subassembly  41  (FIG.  9 ). In the present case, this subassembly is designed in accordance with DE 198 04 614.6. According to this document, reels  42 ,  43  are made available. Once the reel  43  has been used up, the reel  42  is to be connected to a finishing material web. The connection is carried out automatically by a splicing unit  44 . 
     The splicing subassembly  41  also accommodates a reel  45  for the material web  36  for producing the cleaning blanks  35 . The splicing subassembly  41  is designed such that, when the packaging machine is emptied, the web  36  of the cleaning material is connected to a finishing web  46  of the packaging material. According to the example of FIG. 8, this web  46  is a paper web, to which the material web  36 , which likewise consists of paper or a paper-like material, is automatically connected with the aid of the splicing unit  44 . For this purpose, the reel  45  is provided, above the splicing unit  44 , on a common carrying framework  47 . The reel  45  is positioned—in a manner analogous to the reels  42 ,  43 —on a carrying stub  48 . 
     When use is made of a cleaning body  22  of the design according to FIGS. 4 and 5, the (additional) use of the cleaning blanks  35  is dispensed with. 
     LIST OF DESIGNATIONS 
       10  Folding turret 
       11  Cigarette magazine 
       12  Pocket conveyor 
       13  Charging station 
       14  Pocket 
       15  Folding mandrel 
       16  Blank station 
       17  Blank station 
       18  Transfer turret 
       19  Drying turret 
       20  Drying shaft 
       21  Conveying device 
       22  Cleaning body 
       23  Core 
       24  Covering 
       25  Tubular bag 
       26  Block 
       27  End surface 
       28  Brush 
       29  Shaft wall 
       30  Shaft wall 
       31  Shaft wall 
       32  Shaft wall 
       33  Guide wall 
       34  Guide wall 
       35  Cleaning blank 
       36  Material web 
       37  Feed roller 
       38  Transfer device 
       39  Container 
       40  Removal roller 
       41  Splicing subassembly 
       42  Reel 
       43  Reel 
       44  Splicing unit 
       45  Reel 
       46  Web 
       47  Carrying framework 
       48  Carrying stub
Method of cleaning packaging machines, in particular cigarette packaging machines, with the aid of cleaning bodies ( 22) which are directed through the packaging machine instead of pack contents and packaging material. The cleaning bodies ( 22) are thus configured and dimensioned in approximately the same way as the pack contents--cigarette group--or pack.