Abstract
Shown and described is an apparatus for the pre-folding of packaging sleeves including: at least one folding device with folding tools for pre-folding the bottom surfaces of a packaging sleeve and at least one folding device with folding tools for pre-folding the gable surfaces of a packaging sleeve. In order to achieve a precise and rapid pre-folding of the gable surfaces of a packaging sleeve on a compact system, it is proposed that all the folding devices are mounted movably in the vertical and in the horizontal direction. In addition, a method for the pre-folding of packaging sleeves is shown and described.
Claims
1.-25. (canceled)
26. An apparatus for the pre-folding of packaging sleeves comprising: at least one folding device with folding tools for pre-folding the bottom surfaces of a packaging sleeve and at least one folding device with folding tools for pre-folding the gable surfaces of a packaging sleeve, wherein all the folding devices are mounted movably in the vertical and in the horizontal direction.
27. The apparatus according to claim 26, further comprising a rotary frame which is mounted rotatably about an axis of rotation running centrally through the device.
28. The apparatus according to claim 27, wherein the rotary frame comprises vertically running rods on which the folding devices are mounted movably.
29. The apparatus according to claim 27, further comprising a stationary fixed frame which is disposed inside the rotary frame.
30. The apparatus according to claim 29, further comprising a lower control rail which is fastened to the fixed frame and along which the at least one folding device for pre-folding the bottom surfaces of the packaging sleeves is movably guided.
31. The apparatus according to claim 30, further comprising an upper control rail which is fastened to the fixed frame and along which the at least one folding device for pre-folding the gable surfaces of the packaging sleeves is movably guided.
32. The apparatus according to claim 31, wherein the lower control rail and/or the upper control rail have a thickness which varies along their length.
33. The apparatus according to claim 26, wherein the folding devices comprise a rigid frame and a carriage which is mounted movably relative to the frame.
34. The apparatus according to claim 33, wherein the movable carriage is connected mechanically to the folding tools.
35. The apparatus according to claim 33, wherein the movable carriage is connected mechanically to a control carriage by at least one guide rail.
36. The apparatus according to claim 35, wherein the control carriage is connected mechanically to the folding tools by at least one coupling rod.
37. The apparatus according to claim 33, wherein the folding devices have at least one spring which is clamped between the frame and the movable carriage.
38. The apparatus according to claim 26, wherein the apparatus comprises at least six folding devices for pre-folding the bottom surfaces of the packaging sleeves and at least six folding devices for pre-folding the gable surfaces of the packaging sleeves.
39. The apparatus according to claim 26, wherein each folding device comprises a plurality of movably mounted folding tools.
40. The apparatus according to claim 26, further comprising means for positive connection to a conveyor belt with cells fastened thereon.
41. A method for pre-folding packaging sleeves comprising the following steps: a) aligning a packaging sleeve, b) pre-folding the gable surfaces of the packaging sleeve and c) pre-folding the bottom surfaces of the packaging sleeve, wherein steps b) and c) overlap in time, wherein the packaging sleeve is moved in the horizontal direction in steps b) and c).
42. The method according to claim 41, wherein the packaging sleeve is moved at constant speed.
43. The method according to claim 41, wherein the packaging sleeve is moved along a circular path.
44. The method according to claim 41, wherein the packaging sleeve is moved by a conveyor belt with holders or cells fastened thereon.
45. The method according to claim 41, wherein in steps b) and c) a counterholder is inserted into the packaging sleeve.
46. The method according to claim 41, wherein in steps b) and c) two oppositely arranged surface folders are pivoted in the direction of the packaging sleeve.
47. The method according to claim 41, wherein in steps b) and c) two oppositely arranged ear folders are pivoted away from the packaging sleeve.
48. The method according to claim 41, wherein step b) begins earlier than step c).
49. The method according to claim 41, wherein step c) ends earlier than step b).
50. The method according to claim 41, wherein step b) and step c) run completely synchronously.
Description
[0045] The invention is explained in detail hereinafter with reference to drawings showing merely one exemplary embodiment. In the figures:
[0046] FIG. 1A shows a blank for folding a packaging sleeve known from the prior art,
[0047] FIG. 1B shows a packaging sleeve known from the prior art which is formed from the blank shown in FIG. 1A, in the flat-folded state,
[0048] FIG. 1C shows the packaging sleeve from FIG. 1B in the unfolded state,
[0049] FIG. 1D shows the packaging sleeve from FIG. 1C with pre-folded bottom and gable surfaces,
[0050] FIG. 2A shows an apparatus according to the invention for pre-folding packaging sleeves in a front view,
[0051] FIG. 2B shows an enlarged view of a folding device from FIG. 2A,
[0052] FIG. 3 shows a schematic view of the process steps in the pre-folding of packaging sleeves,
[0053] FIG. 4A shows the folding tools of an apparatus according to the invention in the open position in a side view,
[0054] FIG. 4B shows the folding tools of an apparatus according to the invention in the closed position in a side view,
[0055] FIG. 4C shows the folding tools in the position from FIG. 4A in cross-section,
[0056] FIG. 4D shows the folding tools in the position from FIG. 4B in cross-section,
[0057] FIG. 5A shows the folding tools of an apparatus according to the invention in the open position in the cross-section along the line VA-VA from FIG. 4A,
[0058] FIG. 5B shows the folding tools of an apparatus according to the invention in the closed position in the cross-section along the line VB-VB from FIG. 4B, and
[0059] FIG. 6 shows a system known from the prior art for filling packages with foodstuffs.
[0060] FIG. 1A shows a blank 1 known from the prior art from which a packaging sleeve can be formed. The blank 1 can comprise a plurality of layers of different materials, for example, paper, board, plastic or metal, in particular aluminium. The blank 1 has a plurality of fold lines 2 which should facilitate the folding the blank 1 and divides the blank 1 into a plurality of surfaces. The blank 1 can be divided into a first side surface 3, a second side surface 4, a front surface 5, a rear surface 6, a sealing surface 7, bottom surfaces 8 and gable surfaces 9. A packaging sleeve can be formed from the blank 1 by folding the blank 1 in such a manner that the sealing surface 7 can be joined, in particular welded to the front surface 5.
[0061] FIG. 1B shows a packaging sleeve 10 known from the prior art in the flat folded state. The regions of the packaging sleeve already described in connection with FIG. 1A are provided with corresponding reference numbers in FIG. 1B. The packaging sleeve 10 is formed from the blank 1 shown in FIG. 1A. For this purpose, the blank 1 was folded in such a manner that the sealing surface 7 and the front surface 5 are arranged in an overlapping manner so that the two surfaces can be welded flat to one another. As a result, a longitudinal seam 11 is formed. FIG. 1B shows the packaging sleeve 10 in a flat folded-together state. In this state one side surface 4 (concealed in FIG. 1B) lies under the front surface 5 whilst the other side surface 3 lies on the rear surface 6 (concealed in FIG. 1B). In the flat folded-together state a plurality of packaging sleeves 10 can be stacked in a particularly space-saving manner. Thus, the packaging sleeves 10 are frequently stacked at the place of manufacture and are transported in stacks to the filling location. Only there are the packaging sleeves unstacked and unfolded in order to be able to be filled with contexts, for example, with foodstuffs.
[0062] FIG. 1C shows the packaging sleeve 10 from FIG. 1B in the unfolded state. Here also the regions of the packaging sleeve 10 already described in connection with FIG. 1A or FIG. 1B are provided with corresponding reference numbers. The unfolded state is understood as a configuration in which an angle of about 90 is formed between the two respectively adjacent surfaces 3, 4, 5, 6, so that the packaging sleeve 10depending on the shape of these surfaceshas a square or rectangular cross-section. Accordingly the opposite side surfaces 3, 4 are arranged parallel to one another. The same applies for the front surface 5 and the rear surface 6.
[0063] FIG. 1D shows the packaging sleeve 10 from FIG. 1C in the pre-folded state, i.e. in a state in which the fold lines 2 have been pre-folded both in the region of the bottom surfaces 8 and in the region of the gable surfaces 9. These regions of the bottom surfaces 8 and the gable surfaces 9 which adjoin the front surface 5 and the rear surface 6 are also designated as rectangular surfaces 12. The rectangular surfaces 12 are folded inwards during the pre-folding and subsequently form the bottom or the gable of the packaging. Those regions of the bottom surfaces 8 and the gable surfaces 9 which adjoin the side surfaces 3, 4 are on the other hand designated as triangular surfaces 13. The triangular surfaces 13 are folded outwards during the pre-folding and form projecting regions of excess material which are also designated as ears 13 and in a subsequent manufacturing step are placed on the packagingpossibly by gluing processes.
[0064] FIG. 2A shows an apparatus 14 according to the invention for the pre-folding of packaging sleeves 10 in a front view. The apparatus 14 shown in FIG. 2A comprises a rotary machine. The apparatus 14 comprises a rotary frame 15 which comprises a plurality of vertically running supporting elements 15 and a plurality of horizontally running supporting elements 15. The apparatus 14 additionally has a fixed frame 16 which is disposed inside the rotary frame 15. The rotary frame 15 is rotatably connected to a base 18 by a bearing 17 which preferably comprises an axial roller bearing. The rotary frame 15 can therefore rotate about an axis of rotation 19 which runs in the vertical direction centrally through the apparatus 14. The fixed frame 16 on the other hand is connected directly to the base 18 and therefore cannot rotate. The apparatus 14 accordingly comprises a rotatable part and a non-rotatable part.
[0065] The apparatus 14 has a conveyor belt 20 wrapped around itin each case in its region shown in FIG. 2Aapproximately at half height, to which a plurality of cells 21 are fastened. The cells 21 are used to receive packaging sleeves 10 which, for example, can be clamped in the cells 21. The conveyor belt 20 does not wrap around the apparatus 14 completely but only in a partial region which, for example, can be between 160 and 180. In the remaining region, i.e. in the region of the rear side of the apparatus 14 not shown in FIG. 2A, the conveyor belt 20 is detached from the apparatus 14 and leads to other apparatuses which can be part of a filling system for foodstuffs.
[0066] The rotation of the rotary frame 15 can be achieved in various ways. One variant can provide that the rotary frame 15 has its own drive, for example, an electric motor. This drive can rotate the rotary frame 15 and at the same time drive the conveyor belt 20.
[0067] An alternative variant can provide that the rotary frame 15 does not have its own drive but is co-rotated with the conveyor belt 20. In this case, the conveyor belt 20 must naturally be driven by a drive outside the apparatus 14. In order to be able to transfer the drive forces between the rotary frame 15 and the conveyor belt 20, preferably a positive connection is formed between both parts. To this end the inner side of the conveyor belt 20 can, for example, have teeth whichas in the case of a toothed beltengage in correspondingly shaped teeth which are provided on the rotary frame 15. By means of a positive connection, a synchronous movement of rotary frame 15 and conveyor belt 20 can be achieved.
[0068] The apparatus 14 shown in FIG. 2A additionally has two control rails 22 of which the upper control rails 22 is disposed above the conveyor belt 20 and of which the lower control rail 22 is disposed underneath the conveyor belt 20. The control rails 22 are fastened to the stationary fixed frame 16 and therefore do not co-rotate during a rotation of the rotary frame 15. Nevertheless it can be provided that the distance between the upper control rail 22 and the lower control rail 22 is adjustable in order to be able to manufacture or process packagings having different filling volumes. To this end the upper control rails 22 and/or the lower control rail 22 can, for example, be designed to be displaceable in the vertical direction. Preferably the distance between the two control rails 22 can be adjusted in predefined stages, where the stages correspond to different packaging formats. The vertical adjustability of the control rails 22 can, for example, be achieved by a stop and a locking device (not shown in FIG. 2A). Both control rails 22 carry a plurality of folding devices 23 which in turn can be divided into upper folding devices 23 and lower folding devices 23. The folding devices 23 have a rigid frame 24 which is displaceably mounted on rods 25 which for their part are firmly connected to the rotary frame 15. In this way the folding devices 23 can be displaced upwards and downwards in the vertical direction, i.e. parallel to the axis of rotation 19. Respectively one movable carriage 26 which is displaceably mounted is provided inside the rigid frame 24 of the folding devices 23. The carriage 26 can therefore be moved upwards and downwards relative to the frame 24 of the folding device 23. Each folding device 23 additionally has folding tools 27 for pre-folding the packaging sleeves 10.
[0069] The mounting and guidance of the folding devices 23 by the control rails 22 is accomplished in the apparatus 14 shown in FIG. 2A via rotatably mounted rollers 28. Each folding device 23 comprises a frame roller 28 connected to the frame 24 and a carriage roller 28 connected to the movable carriage 26. Each folding device 23 additionally has at least one spring 29 which for example comprises a spiral spring made of steel. Preferably the number of springs 29 per folding device 23 corresponds to the number of rods 25 so that the springs 29 run around the rods 25 and can be centred by these. The springs 29 are disposed in such a manner between the frame 24 and the moveable carriage 26 that they produce a compressive force which presses the carriage roller 28 permanently in the direction of the frame roller 28. As a result of this compressive force produced by the springs 29, the control rail 22 is clamped between the two rollers 28. During a rotation of the rotary frame 15, the rollers 28 of the folding devices 23 rotating together with the rotary frame 15 therefore roll on the surface of the stationary control rails 22. This has the consequence that the distance between the frame roller 28 and the carriage roller 28and therefore also the distance between the frame 24 and the movable carriage 26depends on the thickness D of the control rail 22. In regions in which the control rail 22 is thin or narrow, the carriage roller 28 and therefore also the movable carriage 26 are pressed very tightly onto the frame roller 28 by the springs 29. In regions in which the control rail 22 is thick or wide, the springs 29 are on the other hand compressed again so that the carriage roller 28 and therefore also the movable carriage 26 are again moved away from the frame roller 28.
[0070] In order to ensure a safe, controlled stopping of the rotary frame 15 of the apparatus 14 even with broken springs 29, spacersnot shown in FIG. 2Acan be provided on the movable carriages 26 of the upper and lower folding devices 23, 23. The spacers ensure that the movable carriages 26and therefore also the carriage rollers 28only move insignificantly further away from the frame rollers 28 than would be the case with functioning springs 29 in the maximum deflection of the movable carriages 26. In this way it is achieved that even with broken springs 29, the control rails 22, 22 can still provide acertainly only very looseguidance for the two rollers 28, 28. Preferably the spacers are configured to be adjustable.
[0071] In the apparatus 14 shown in FIG. 2A the movable carriages 26 are connected mechanically to the folding tools 27. This enables the folding tools 27 to be actuated by a movement of the carriages 26. The precise type of connection will be discussed in more detail in connection with FIG. 2B. For example, the folding tools 27 can be activated when the distance between the carriage rollers 28 and the frame rollers 28 is reduced and deactivated when the distance between the carriage rollers 28 and the frame rollers 28 is increased again. As a result of this arrangement, the control rails 22 can influence and control the folding devices 23 in multiple ways: as a result of a variation in the position of the control rails 22 the positions of the folding devices 23 can be varied; in particular, the folding devices 23 can be displaced in the vertical direction. As a result of a variation in the thickness D of the control rails 22 on the other hand, the positions of the movable carriages 26 relative to the frames 24 of the folding devices 23 can be varied whereby the folding tools 27 can be influenced.
[0072] FIG. 2B shows an enlarged view of a folding device 23 from FIG. 2A. The regions of the folding device 23 already described in connection with FIG. 2A are provided with corresponding reference numbers in FIG. 2B. The folding device 23 shown in FIG. 2B comprises an upper folding device 23; for the lower folding devices 23 however the same applies accordingly. As has already been described in connection with FIG. 2A, a variation in the thickness D of the control rail 22 results in a displacement of the movable carriage 26 in the vertical direction. As a result of a movement of the carriage 26, the folding tools 27 are activated or deactivated. For this purpose there is a mechanical connection between the carriage 26 and the folding tools 27.
[0073] In the folding device 23 shown in FIG. 2B and in this respect preferred, the mechanical connection between the movable carriage 26 and the folding tools 27 is implemented as follows: the carriage 26 transfers its vertical movement to a control carriage 30. The control carriage 30 is connected by means of two guide rails 31 to the movable carriage 26 in such a manner that the distance between the movable carriage 26 and the control carriage 30 is always constant. In other words, the carriage 26 and the control carriage 30 move relative to the frame 24 of the folding device 23 but not relative to one another. The synchronous movement of carriage 26 and control carriage 30 can, for example, be achieved by both the carriage 26 and also the control carriage 30 being firmly connected to the guide rails 31 whilst the guide rails 31 are movably guided in the frame 24 of the folding device 23 and therefore can be displaced relative to the folding device 23. The control carriage 30 is mechanically connected to the folding tools 27. This can be accomplished, for example, by coupling rods 32 mounted in an articulated manner.
[0074] In FIG. 2B the folding tools 27 are only shown schematically by a rectangular block. Preferably a folding device 23 according to the invention comprises five folding tools 27. Two of these folding tools 27 can be arranged opposite to one another, pivotably mounted and be used for the pre-folding of the rectangular surfaces 12 of the packaging sleeves 10. Two further ones of these folding tools 27 are also be arranged opposite one another, be pivotably mounted and be used for pre-folding the triangular surfaces 13 of the packaging sleeves 10. During a vertical movement of the carriage 26 these four folding tools 27 are pivoted by the coupling rods 32 or comparable mechanical elementsnot shown in FIG. 2Bin such a manner that they contact the packaging sleeve 10 and pre-fold in the region of its bottom surface 8 or its gable surface 9. The fifth folding tools 27 can comprise a counterholder whose shape approximately corresponds to the cross-sectional area of the packaging sleeve 10. This enables the counterholder to be inserted into the packaging sleeve 10 before or during the pivoting movement of the other four folding tools 27 and to serve there as a stop for the other four folding tools 27. In contrast to the other four folding tools 27 the counterholder does not need to be pivotably mounted. Accordingly, it does not need to be controlled via the carriages 26, the control carriages 30 and the coupling rods 32 but can be firmly connected to the frame 24 and thus follow the vertical movement of the folding device 23.
[0075] FIG. 3 comprises a schematic view of the process steps during the pre-folding of packaging sleeves 10. For illustration the operating mode of an apparatus 14 according to the invention is conceptually divided into eight positions I-VIII in FIG. 3 which are each shown individually. For reasons of simplification many details of the apparatus 14 are omitted in FIG. 3. The regions of the apparatus 14 already described in connection with FIG. 2A or FIG. 2B are also provided with corresponding reference numbers in FIG. 3. Shown in particular are the upper control rail 22 and the lower control rail 22. The folding devices 23 are guided along the two control rails 22; this is accomplished by means of the rollers 28, 28.
[0076] In position I both control rails 22 are so far away from the conveyor belt 20 that the folding devices 23 and in particular the folding tools 27 fastened thereon have no contact with the packaging sleeves 10 which are located in the cells 21 of the conveyor belt 20. In the position shown in position I the control rails 22 have a large thickness D so that the movable carriages 26 are pressed in the direction of the folding tools 27. This has the result that the folding tools 27 are opened.
[0077] In position II the position of the lower folding device 23 is unchanged. The upper folding device 23 on the other hand has moved in the direction of the packaging sleeve 10 to be folded as a result of change in position of the upper control rail 22. This has the result that the folding tools 27 of the upper folding device 23 are located in the vicinity of the upper region of the packaging sleeve 10, i.e. in the region of the gable surfaces 9. In this position the folding process can be carried out. Since the thickness D of the upper control rail 22 in position II however is unchanged, the position of the movable carriage 26 has not changed compared to position I so that the folding tools 27 of the upper folding device 23 are in the open position as before.
[0078] Between position II and position III the lower folding device 23 is displaced in the direction of the packaging sleeve 10 to be folded as a result of a change in position of the lower control rail 22. In position III accordingly both the upper folding device 23 and the lower folding device 23 are located in a position in which the folding process can be carried out. However, the thickness D of the lower control rail 22 is unchanged in position III so that the position of the movable carriage 26 of the lower folding device 23 has not changed compared with position I and position II. The folding tools 27 of the lower folding device 23 in position III are therefore as before in the open position so that no folding process is carried out. The thickness D of the upper control rail 22 has however decreased significantly from position II to position III so that the movable carriage 26 of the upper folding device 23 is pressed by the springs 29 in the direction of the upper control rail 22. As a result of a mechanical connection between the movable carriage 26 and the folding tools 27, the described movement of the carriage 26 results in an actuation of the folding tools 27 of the upper folding device 23. Due to the actuation of the folding tools 27 of the upper folding device 23 the packaging sleeve 10 is firstly precisely aligned and then pre-folded in the region of the gable surfaces 9. The alignment of the packaging sleeve 10 is in particular possible since the folding tools 27 of the lower folding device 23 in position III are not yet actuated so that the packaging sleeve 10 can still be displaced relative to the lower folding device 23.
[0079] Between position III and position IV the thickness D of the lower control rail 22 also decreases so that the folding tools 27 of the lower folding device 23 are also actuated as a result of a displacement of the movable carriage 26. In position IV therefore both the folding tools 27 of the upper folding device 23 and also the folding tools 27 of the lower folding device 23 are active and in contact with the packaging sleeve 10.
[0080] Between position IV and position V the thickness D of the lower control rail 22 increases again with the result that the movable carriage 26 is again pressed in the direction of the packaging sleeve 10. This has the result that the folding tools 27 of the lower folding device 23 open again and release the packaging sleeve 10. The pre-folding of the bottom surfaces 8 of the packaging sleeve 10 is now completed. The folding tools 27 of the upper folding device 23 in position V on the other hand are active as before. The position of the components in positions III and V is identical.
[0081] Between position V and position VI the position of the lower control rail 22 changes again with the result that the lower folding device 23 is again moved away from the packaging sleeve 10. The position of the upper folding device 23 in position VI on the other hand is unchanged compared to position V. In the upper control rail 22 not the position but the thickness D of the upper control rail 22 varies between positions VI and VII. As a result of an increase in the thickness D of the upper control rail 22 the movable carriage 26 of the upper folding device 23 is again pressed in the direction of the packaging sleeve 10 with the result that the folding tools 27 of the upper folding device 23 open again. Now the pre-folding of the gable surfaces 9 of the packaging sleeve 10 is completed. The position of the lower components in positions VI and II is identical; the position of the upper components on the other hand only again reaches the position from position II in position VII.
[0082] In position VIII the position of the lower folding device 23 is unchanged compared with position VI and position VII. On the other hand, as a change in position of the upper control rail 22 between position VII and position VIII, the upper folding device 23 has been displaced in the direction of the upper control rail 22. In position VIII accordingly both control rails 22 are so far away from the conveyor belt 20 that the folding devices 23 and in particular the folding tools 27 fastened thereon have no contact with the packaging sleeves 10 which are located in the cells 21 of the conveyor belt 20. A comparison between positions I and VIII shows outwardly folded triangular surfaces 13 as a result of the pre-folding. The rectangular surfaces 12 are on the other hand inwardly folded as a result of the pre-folding; however this cannot be identified in the view selected in FIG. 3.
[0083] FIG. 4A shows the folding tools 27 of an apparatus 14 according to the invention in the open position in a side view. In the apparatus 14 shown in FIG. 4A and in this respect preferred, there are five folding tools 27: the first folding tool 27 comprises a centrally arranged counterholder 27A which is introduced into the interior of the packaging sleeve 10 and whose shape approximately corresponds to the cross-sectional area of the packaging sleeve 10. In addition, there are provided two oppositely arranged surface folders 27B which are pivotably mounted. The surface folders 27B serve to fold the rectangular surfaces 12 of the packaging sleeve 10 inwards. Finally there are provided two oppositely arranged ear folders 27C which are also pivotably mounted. The rear one of the two ear folders 27C in FIG. 4A is concealed. The ear folders 27C serve to support one of the triangular surfaces 13 against the pressure of the surface folders 27B from below in order to form the ears 13 of the packaging sleeve 10. For this purpose the ear folders 27C have a triangular region. The movements of the folding elements 27A, 27B and 27C are shown schematically by arrows.
[0084] FIG. 4B shows the folding tools 27 of an apparatus 14 according to the invention in the closed position in a side view. Compared to the open position from FIG. 4A, the two ear folders 27C have been pivoted outwards, i.e. away from the packaging sleeve 10 so that the triangular region of the ear folders 27C can serve as a support for folding the ears 13. The two surface folders 27B on the other hand have been pivoted inwards, i.e. towards the packaging sleeve 10 where the rectangular surfaces 12 of the packaging sleeve 10 also bend inwards. The position of the counterholder 27A is unchanged. In the position shown in FIG. 4B the two surface folders 27B press the gable surfaces 9 of the packaging sleeve 10 downwards, where (outside the packaging sleeve 10) the ear folders 27B and (inside the packaging sleeve 10) the counterholder 27A serve as a support.
[0085] FIG. 4C shows the folding tools 27 in the position from FIG. 4A in cross-section. The regions of the apparatus 14 already described in connection with FIG. 4A are provided with corresponding reference numbers in FIG. 4C. The tapered shape of the counterholder 27A can be seen particularly clearly, which counterholder firstly serves to provide two flat contact surfaces for the surface folders 27B and secondly enables the two rectangular surfaces 12 of the packaging sleeve 10 to be compressed as tightly as possible. In contrast to FIG. 4A, the rear ear folder 27C is shown in FIG. 4C.
[0086] FIG. 4D shows the folding tools 27 in the position from FIG. 4B in cross-section. The regions of the apparatus 14 already described in connection with FIG. 4B are provided with corresponding reference numbers in FIG. 4D. The course of the wall of the packaging sleeve 10 can be seen particularly clearly (shown in bold). The wall of the packaging sleeve 10 is compressed between the two surface folders 27B and (outside the packaging sleeve 10) the ear folders 27C as well as (inside the packaging sleeve 10) the counterholder 27A and thereby pre-folded. In contrast to FIG. 4B, the rear ear folder 27C is shown in FIG. 4D.
[0087] FIG. 5A shows the folding tools 27 of an apparatus 14 according to the invention in the open position in cross-section along the line VA-VA from FIG. 4A. The regions of the apparatus 14 already described in connection with FIG. 4A to FIG. 4D are provided with corresponding reference numbers in FIG. 5A. The counterholder 27A can be configured to be slightly wider in the transverse direction of the packaging sleeve 10, i.e. parallel to the front surface 5 and the rear surface 6, than the width of the front surface 5 and the rear surface 6. This has the effect that the triangular surfaces 13 of the packaging sleeve 10 are gently pressed outwards during insertion of the counterholders 27A and already abut against the ear folders 27C before the actual pre-folding.
[0088] Figure SB shows the folding tools 27 of an apparatus 14 according to the invention in the closed position in cross-section along the line VB-VB from FIG. 4B. The regions of the apparatus 14 already described in connection with FIG. 4A to FIG. 4D are provided with corresponding reference numbers in FIG. 5B. The outwardly projecting ears 13 of the packaging sleeve 10 can be identified particularly clearly. The ears 13 are formed whereby the two surface folders 27B (not shown in FIG. 5B) press the wall of the packaging sleeve 10 particularly in the region of the triangular surfaces 13 onto the two ear folders 27C.
[0089] The shape of the gable surfaces 9 of the packaging sleeve 10 achieved in FIG. 4B, FIG. 4D and FIG. 5B cannot be completely retained since the counterholder 27A must again be withdrawn upwards from the packaging sleeve 10 and thereby hits against the rectangular surfaces 12. In addition, a sufficiently large opening must be provided for the subsequent filling of the packaging sleeve 10. As a result of the withdrawal of the counterholder 27A and as a result of the elasticity of the material of the packaging sleeve 10, the gable surfaces 9 of the packaging sleeve 10 again move backwards a little way so that after completion of the pre-folding the packaging sleeve 10 approximately adopts the shape described previously in connection with FIG. 1D. FIG. 6 shows a system 33 known from the prior art for filling packages with foodstuffs (EP 0 112 605 A2). The individual stations of the system 33 are only shown schematically in FIG. 6 since FIG. 6 is merely intended to illustrate a possible area of application of an apparatus 14 according to the invention for the pre-folding of packaging sleeves 10. The packaging sleeves 10 (not shown in FIG. 6) are unfolded by a station 34 and transferred to the cells 21 of the conveyor belt 20. The system 33 comprises a first rotary machine 35 in which the gable surfaces 9 of the packaging sleeves 10 are pre-folded. The packaging sleeves 10 then pass through a station 36 in which the bottom surfaces 8 of the packaging sleeves 10 are pre-folded. The stations 35 and 36 can be replaced by an apparatus according to the invention. After the pre-folding the bottom surfaces 8 of the packaging sleeves 10 are folded together in a station 37 and sealed. The conveyor belt 20 is then guided around a second rotary machine 38 in which the packaging sleeves 10 closed on the underside are filled with foodstuffs. In a further station 39 the gable surfaces 9 of the packaging sleeves 10 are folded together and sealed. Finally in a further station 40 the packaging sleeves 10 now filled and closed are removed from the cells 21 of the conveyor belt 20 and again discharged from the system 33.
LIST OF REFERENCE NUMBERS
[0090] 1: Blank [0091] 2: Fold line [0092] 3, 4: Side surface [0093] 5: Front surface [0094] 6: Rear surface [0095] 7: Sealing surface [0096] 8: Bottom surface [0097] 9: Gable surface [0098] 10: Packaging sleeve [0099] 11: Longitudinal seam [0100] 12: Rectangular surface [0101] 13: Triangular surface [0102] 13: Ears [0103] 14: Apparatus [0104] 15: Rotary frame [0105] 15, 15: Supporting element [0106] 16: Fixed frame [0107] 17: Bearing [0108] 18: Base [0109] 19: Axis of rotation [0110] 20: Conveyor belt [0111] 21: Cell [0112] 22, 22, 22: Control rail [0113] 23, 23, 23: Folding device [0114] 24: Frame [0115] 25: Rod [0116] 26: Carriage [0117] 27: Folding tool [0118] 27A: Counterholder [0119] 27B: Surface folder [0120] 27C: Ear folder [0121] 28, 28, 28: Roller [0122] 29: Spring [0123] 30: Control carriage [0124] 31: Guide rail [0125] 32: Coupling rod [0126] 33: System [0127] 34: Station for unfolding [0128] 35: Station for pre-folding gable surfaces [0129] 36: Station for pre-folding bottom surfaces [0130] 37: Station for folding and sealing bottom surfaces [0131] 38: Station for filling [0132] 39: Station for folding and sealing gable surfaces [0133] 40: Station for discharging [0134] D: Thickness (of control rail 22)
