Method and device for manufacturing hinge-lid packets

Abstract
Blanks (10) made of thin cardboard for hinge-lid packets or similar are produced in the region of a packaging machine. To this end, a material web (19) made of thin cardboard and if necessary partially pre-prepared, is led through a blanks device (20) in the region of the packaging machine. The blanks device (20) can if necessary apply printing (29) to the material web (19) as well as embossing, grooves, punched-out lines, until the blanks (10) are completely produced by a transverse severance cut (32).
Description




BACKGROUND OF THE INVENTION




The invention relates to a method of manufacturing (cigarette) packets of the hinge-lid type by folding blanks made of (thin) cardboard in a packaging machine, the blanks being prepared by stamping and having punched-out lines on them as well as folding lines formed by embossing. In addition, the invention relates to a device for carrying out this method.




Hinge-lid packets are a type of packet for cigarettes which are now common throughout the world. The hinge-lid packets consist of a (lower) packet portion and a lid attached with a hinge to a rear wall of same. In addition, this type of packet includes a collar—likewise made of thin cardboard—which can be connected to the blank for the hinge-lid packet or manufactured from a separate blank.




The blanks for this type of packet have up to now been manufactured separately, especially in a paper factory. The blanks, printed (on one side) and provided with punched-out lines and embossing lines for folding, are delivered as piles of blanks and passed into the packaging machine, usually in shaft-like blanks magazines. The material supply for the packaging machine in respect of the blanks is thus expensive and susceptible to being interrupted.




SUMMARY OF THE INVENTION




The purpose underlying the invention is to improve the supply of packaging machines with blanks made of thin cardboard, especially for the production of hinge-lid packets, in respect of their efficiency and reliability.




In fulfilment of this purpose, the method according to the invention is characterised in that the blanks are manufactured in the region of the packaging machine by being separated from a material web made of (thin) cardboard and are provided by embossing with folding lines and by stamping with punched-out lines, and in that the blanks are then directly or indirectly led to a folding assembly of the packaging machine.




The basic idea of the proposal according to the invention is to produce blanks from thin cardboard for the production of hinge-lid packets directly in the region of the packaging machine, by separating them from a continuous web of material, in the region of which the stretched-out blanks are aligned beside one another transversely. The web of material is drawn from a reel in the region of the packaging machine. To this extent, the supply of material to the packaging machine takes place in an analogous way to the handling of thin packaging material made of paper or foil.




In an optimum solution of the invention, the web of material is led through a blanks assembly. In the region of same, the web of material is provided on the (later) outer side of the hinge-lid packets with the necessary printing. Moreover, as far as this is necessary, embossing can take place in order to form symbols represented by embossing. Finally the material web runs through a stamping and grooving assembly, in the region of which the punched-out lines and folding lines are applied by embossing, namely by making grooves, and the blanks are divided from the material web by transverse severance cuts.




According to the invention, the completed blanks are collected forming stacks and are led via vertical and horizontal conveyors to a blanks magazine on the machine side.




A further special characteristic of the invention consists in the fact that the deformation that has occurred through the material web having been stored in a roll, namely curvatures in the region of the blanks, are removed. To this end, the material web is led through a counter-shaping assembly, especially over deforming rollers. The amount of the counter deformation of the material web can be adjusted according to the invention, according to the measurement of the diameter of the reel. The decreasing diameter of said reel during the use of the packaging material is therefore monitored according to the invention.




The device according to the invention for carrying out the method is an additional device for a packaging machine for hinge-lid packets. It is connected with the packaging machine via vertical and horizontal conveyors.




Further details of the invention relate to the method and the device for manufacturing and processing the blanks for hinge-lid packets, including measures for recognising and removing faulty blanks.











BRIEF DESCRIPTION OF THE DRAWINGS




Embodiments, given by way of example, and details of the method and of the device are explained in greater detail below with the aid of the drawings. These show:





FIG. 1

a section of the material web made of thin cardboard, in plan view,





FIG. 2

a blank for hinge-lid packets, separated from the material web as per

FIG. 1

,





FIG. 3

a packaging machine with a connected blanks device, in simplified plan view,





FIG. 4

the packaging machine according to

FIG. 3

with the blanks device in side view, on an enlarged scale,





FIG. 5

an embodiment of a blanks device, in diagrammatic side view,





FIG. 6

a unit of the blanks device in side view, on an enlarged scale,





FIG. 7

a blanks station as a detail of the blanks device in side view, on a further enlarged scale,





FIG. 8

a distributing station for blanks in side view, on a further enlarged scale,





FIG. 9

a cross-section through a detail of the blanks device, in the region of the handling of piles of blanks,





FIG. 10

a section of a material web for blanks according to a different manufacturing process,





FIG. 11

a packaging machine with a blanks device in diagrammatic plan view for the manufacture of blanks according to the method as per

FIG. 10

,





FIG. 12

a partial region of the device as per

FIG. 11

in side view,





FIG. 13

the blanks device for the embodiment as per

FIG. 11

, in simplified, enlarged side view,





FIG. 14

a partial region, namely a blanks station of the device according to

FIG. 13

on a further enlarged scale.











DESCRIPTION OF PREFERRED EMBODIMENTS





FIG. 2

shows a blank


10


, formed in typical manner, for the production of a hinge-lid packet for cigarettes. The stretched-out blank


10


consists of a partial region for forming a packet portion


11


and of a further partial region for forming a lid


12


. Contours at the ends of the blank


10


are characteristic. On the one side is formed a closing edge


13


of the packet portion


11


from a transverse section and side sloping arms, such that a trapezoid edge depression of the blank


10


is produced. On the opposite side in the region of the lid


12


, a special contour is produced from a lid inner flap


14


and sloping closing edges


15


of the lid.




In addition, the design of the usable blank


10


is characterised by longitudinal folding lines


16


and transverse folding lines


17


. Finally, punched-out lines


18


for delimiting folding flaps in the region of side walls of the hinge-lid packet form part of the typical appearance of the blank


10


. A more detailed presentation and description of a blank


10


of this sort for hinge-lid packets arises from U.S. Pat. No. 5,462,223.




Blanks


10


, formed thus or in a similar fashion are separated in succession from a continuous web of material


19


. The latter consists of thin cardboard. The material web


19


is drawn from a reel


21


in the region of a blanks device


20


(

FIGS. 3

,


4


, and


5


). The blanks device


20


is a machine for producing complete usable blanks


10


for the manufacture of (cigarette) packets of the hinge-lid type, and can also be used independently. The blanks device


20


is here part of a packaging plant or a packaging machine


22


for the manufacture of this special type of packet.




The blanks device


20


is disposed at a distance from the packaging machine


22


. The blanks


10


are led as piles


23


of blanks from the blanks device


20


by a horizontal conveyor


24


to the packaging machine


22


.




It is important that the material web


19


can be drawn in the region of the blanks device


20


from the reel


21


, which is rotatably mounted on a carrying journal


25


. Offset to this reel, in (approximately) the same horizontal plane, there is located a spare reel


26


likewise on a carrying journal


27


. The spare reel


26


is introduced into the manufacturing process after reel


21


has been used up. The material web


19


is, to this end, led through a splicing assembly


28


, shown diagrammatically. In the region of this splicing assembly, there is (automatic) connection of the material web


19


with a new material web which is to be joined on to same.




The material web


19


can be partially prepared (elsewhere) for processing in the region of the blanks device


20


. Thus the material web


19


can be already provided with printing


29


(cross-hatched areas in FIG.


1


and

FIG. 2

) which corresponds to the finished blanks


10


. In addition, embossing


30


—as far as it is desired on the finished packet—can be applied to the material web


19


in the position that is correct for the packet. Also certain grooves can be present corresponding to folding lines which have to be applied. The preparation of the material web


19


outside the region of the packet production, however, may not impair its ability to be coiled up as a reel.




An important part of the blanks device


20


is a blanks unit


31


. In its region, the blanks


10


are first completed within the material web


19


and then separated from same by a transverse severance cut


32


.




The blanks unit


31


consists of a plurality of successive working assemblies. Each working assembly undertakes a partial function up to the completion of the blanks


10


.




The most important working assembly is a cutting assembly


33


(

FIGS. 5

,


6


, and


7


). This is set up in such a way that the material web


19


is provided in its front end region with the punched-out lines


18


and with embossing or grooves to form the longitudinal folding lines


16


and transverse folding lines


17


(FIG.


2


). Additionally in this region, the end contours of the blanks


10


aligned transversely to the web of material


19


are manufactured by a contoured longitudinal cut


34


,


35


on both longitudinal sides of the material web


19


. Finally, the cutting assembly


33


carries out the transverse severance cut


32


. In the region of the cutting assembly


33


, the blank


10


is correspondingly completed—up to the printing


29


and any possible embossing


30


.




The material web


19


is of greater dimensions than that of the (transverse) blanks


10


. Thus in the region of the cutting assembly


33


, on both side edges of the material web


19


, a piece of material


61


,


62


(

FIG. 1

) is cut off, which extends in each case as far as the edge of the material web


19


and has the respective contour of a blank


10


. Thus on the one side, namely in the region of the longitudinal cut


34


, a trapezoid piece of material


61


is formed. On the opposite side, in the region of the lid inner flap


14


, an approximately U-shaped piece of material


62


is cut off. These pieces of material


61


,


62


are cut off immediately before the transverse severance cut


32


, in such a way that the blank


10


shown in

FIG. 2

is present. The printing


29


is so applied that the longitudinal cuts


34


,


35


—with corresponding design of the blank


10


or of the packet—run inside the printing


29


.




In order to carry out these measures, the cutting assembly


33


is provided with working rollers


36


,


37


which are co-ordinated with one another, and which are configured as cutting and embossing rollers in the distribution of tasks described. The described steps are carried out during the (continuous) passage of the material web


19


.




If—as in the present embodiment—an untreated web of material


19


is made available, the blanks unit


31


is equipped with additional working assemblies, which are placed in front of the cutting assembly


33


in the direction of conveying. Thereafter the material web


19


runs first of all through a printing assembly


38


. In the region of same, the printing


29


is applied in the correct position for the packet whilst the material web


19


is conveyed continuously. The printing assembly


38


consists substantially of an upper printing unit


39


and a lower supporting roller


40


.




The material web


19


, provided for example in the embodiment as per

FIG. 1

with printing


29


, runs here through a further working assembly, namely an embossing assembly


41


. This supplies embossing, likewise in the position which is correct for the packet, for example coats of arms or other emblems. The embossing assembly


41


consists essentially of two co-operating embossing rollers


42


,


43


, between which the material web runs.




The blanks


10


, emerging ready to use out of the blanks unit


31


, are collected, forming piles of blanks


23


. To this end there is a (horizontal) blanks path


44


joining on to the blanks unit


31


. This path consists of a plurality of pairs of rollers


45


which are driven to carry the blanks


10


in a transverse direction. The distances between the pairs of rollers


45


are slightly smaller than the measurement of the blanks


10


in the conveying direction.




Stackers


46


,


47


are arranged in the region of the blanks station. These are containers which are open at the top and on narrow sides and into which the blanks


10


may be conveyed in succession from above. The blanks are laid in the stacker


46


,


47


respectively on a carrying plate


48


which is adjustable in height. This plate is lowered in accordance with the increasing height of the pile


23


of blanks formed in the stacker


46


,


47


. The carrying plate


48


enters the stacker


46


,


47


via an open side. In a lower position, the carrying plate is located at the height of a conveyor


49


for piles of blanks, a belt conveyor. In this lower position of the carrying plate


48


, the pile


23


of blanks in the stacker


46


,


47


is complete. A slide


50


(

FIG. 9

) entering the stacker


46


,


47


via an open side, pushes the pile


23


of blanks out of the stacker


46


,


47


on to the conveyor


49


for the piles of blanks.




On the present embodiment, a fixed bridge plate


51


is disposed between the conveyor for the piles of blanks


49


and the carrying plate


48


. This bridge plate extends at the height of a bight of the conveyor for the piles of blanks. The carrying plate


48


is lowered during the filling process of the stacker


46


,


47


to the level of the bridge plate


51


. When this position is reached, the pile


23


of blanks is pushed by the slide


50


over the bridge plate


51


on to the conveyor


49


for the piles of blanks.




The bridge plate


51


is the lower delimitation of a recess


63


in an upright supporting housing


64


of the blanks device


20


. The piles


23


of blanks are—lying on the bridge plate


51


—pushed through the recess


63


on to the conveyor


49


for the piles of blanks which is arranged beside the supporting housing


64


.




In order to introduce the blanks


10


into one or the other stacker


46


,


47


guide members are positioned in the region of the blanks path


44


. These members are swivellable guide plates


52


,


53


above each stacker


46


,


47


. In an upwardly aligned sloping position (stacker


46


in FIG.


7


and

FIG. 8

) the arriving blanks are led by the guide plate


52


into the associated stacker


46


. In a horizontal position or one aligned obliquely downwards (stacker


47


in FIG.


7


and FIG.


8


), the arriving blank


10


is guided past the relevant stacker


46


,


47


to the next stacker or to another member. The guide plates


52


,


53


are in the present case mounted coaxially with a lower counter-roller


54


of a pair of rollers


45


above the respective stacker


46


,


47


but may, however, be swivelled independently of these counter rollers


54


.




The blanks


10


produced in the region of the blanks unit


31


are checked to see that they are correctly configured. To this end, a monitoring device for blanks


10


is disposed at the exit side of the blanks unit


31


above the blanks path


44


. In the present case, this monitoring device is a camera


55


which monitors the blanks to see that they have the correct printing and other details. The camera


55


—or a different monitoring device—controls the guide plates


52


,


53


.




A faulty blank


10


is conveyed through the blanks path


44


and separated outside the region of the stackers


46


,


47


. On the embodiment shown, faulty blanks of this sort are led into a collecting vessel


56


. The latter is configured here as a pipe-shaped container with an entrance slot


57


on the side facing the blanks path


44


. The collecting vessel


56


is collected via an extraction pipe


58


with a source of negative pressure. Faulty blanks entering the collecting vessel


56


—preferably a horizontal section of pipe—are carried away via the extraction pipe


58


.




The piles


23


of blanks, set down on the conveyor


49


for these piles, are transferred to a vertical conveyor


59


in the region of the blanks device


20


. The vertical conveyor


59


in each case picks up one pile


23


of blanks on a platform


60


. By a forward movement of same, the pile


23


of blanks is raised up to the plane of the horizontal conveyor


24


and transferred to same. The horizontal conveyor


24


extends at a higher plane. The piles


23


of blanks are led from the horizontal conveyor


24


to a blanks magazine in the region of the packaging machine


22


.




A special characteristic of the blanks device


20


consists in the fact that the curvature in the region of the blanks


10


, caused by the coiled form of the material web


19


, i.e. by the reels


21


,


26


, is recognized and appropriately compensated, such that flat blanks can be produced. In concrete terms, to this end the material web


19


, after it has been drawn from the reel


21


or


26


, is treated in a deforming sense, before the web of material


19


runs into the blanks unit


31


.




To this end, the material web—following on to the splicing assembly


28


—is led via a shaping assembly


65


. The latter consists of two stationary deflection rollers


66


and


67


and of a shaping roller


68


arranged between same. The shaping roller is disposed in such a way that the material web running over said shaping roller


68


is deformed against the curvature caused by the reels


21


,


26


.




The extent or the intensity of the compensatory deformation of the material web


19


may be altered, in accordance with the respective deformation of the material web


19


. To this end, the diameter of the respectively running reel


21


is scanned by appropriate known sensors, and the compensatory deformation is controlled in accordance with these. With increasing use of the reel


21


, the material web


19


has greater deformation. Correspondingly, the shaping roller


68


may be adjusted in relation to the deflection rollers


66


,


67


, through upward and downward movement. The upper position, which can be seen in broken lines in

FIG. 5

, causes slight compensatory deformation. The lower position shown causes stronger or maximum compensatory deformation of the material web


19


.




A modified method or a different embodiment of a blanks device


20


is shown in

FIG. 10

to FIG.


14


. In this solution, individual blanks


10


are not produced in the region of a blanks unit


69


. Rather, a web


70


of blanks still adhering to one another emerges from the blanks unit


69


. This web of blanks


70


is configured in accordance with EP 291 692 or similar. The blanks


10


are connected to one another in the region of an (incomplete) severance cut


32


, by a plurality of residual connections


71


. These are thin or narrow material webs which occur through corresponding interruptions of the severance cut


32


. The residual connections


71


can be distributed in an appropriate manner over the length of the blanks


10


or the width of the blanks web


70


, to guarantee a continuous web of blanks


70


. Otherwise the blanks web


70


is produced like the blanks


10


in the preceding embodiment. This is especially true of the printing, and of embossing, grooves and punched-out lines.




The continuous web of blanks


70


is led through a severance assembly


72


. In the region of same, the individual blanks


10


are separated from the web of blank


70


, the residual connections


71


being severed, by cutting or tearing. On the present embodiment, it is not individual blanks


10


which are divided from the web of blanks


70


, but in each case two blanks


10


still adhering to one another, i.e. a pair of blanks


73


.




These blanks units, i.e. pairs of blanks


73


are then led by a corresponding conveyor into the packaging machine


22


. In the region of same, the blanks of each pair


73


are separated from one another by tearing, shearing off or by a severance cut and led directly into pockets of a rotary folding unit


74


. To this extent, the principle of this solution corresponds to EP 312 877.




On the present embodiment, the web of blanks


70


is introduced into a web store


75


. Inside same, a store is formed by zigzag shaped folding of the web of blanks


70


, the folding taking place in each case in the region of the residual connections


71


. The zigzag-shaped web store is formed between (upper and lower) storage belts


76


,


77


. The web store


75


is broken down by the web of blanks


70


being drawn out at one open side from the region of the storage belts


76


,


77


and brought back into an extended position, by a pair of drawing rollers


78


.




At the entrance side of the web store


75


or of the storage belts


76


,


77


, there is located a member for forming the zigzag shape of the web of blanks


70


. These are guide rollers


79


,


80


. In respect of this detail as well as in respect of the design of the web store


75


, reference is made to EP 391 118.




The blanks


10


or the pairs of blanks


73


are separated from the web of blanks


70


in the region of the severance assembly


72


by a tearing process. To this end, two co-operating separating rollers


81


,


82


are provided. These are driven to rotate, at a higher speed than the drawing rollers


78


. Accordingly, the latter hold the subsequent web of blanks


70


tight when the severance rollers


81


,


82


equipped with radially-projecting segments


83


, grasp at a higher rotational speed the respectively front blank


10


or the front pair of blanks


73


with segments


83


and separate them from the web of blanks


70


.




The blanks


10


or pairs of blanks


73


are transferred to a transverse conveyor


84


which carries the pairs of blanks


73


away in the described manner to the packaging machine


22


.




The present embodiment of the blanks device


20


is also configured differently in respect of the arrangement of the reel


21


and of the spare reel


26


. A rocker


85


serves as carrying member for the bobbins


21


,


26


. One reel


21


,


26


is rotatably mounted at each of its ends, between facing carrying bodies


86


,


87


. These are conical peg-like members which enter partially into a central aperture


88


of the reel


21


,


26


. The carrying bodies


86


,


87


are rotatably mounted and lie under pressure on or in the central apertures


88


. The rocker


85


consists of two rocker arms


89


,


90


at the ends of which the carrying bodies


86


,


87


are attached.




The (double-armed) rocker


85


is mounted rotatably on a portal-like carrying frame


91


. A pivot bearing


92


is located in the region of upright supports


93


of the carrying frame


91


. The latter consists of carrying portals, arranged at a spacing from one another, such that one pivot bearing


92


is formed on each of two facing supports


93


for respectively one rocker arm


89


,


90


. A centrally-positioned motor


94


provides the rotary drive for the rocker


85


, in such a way that respectively the upper reel is active, from which the material web


21


is drawn.




Further details of the device are configured analogously to the preceding embodiment. This is especially true also for the shaping assembly


65


. A track link


95


is arranged in front of the latter in the direction of conveying in order to balance out track tensions.




Also on the embodiment according to

FIGS. 10

ff., printing


29


and/or embossing


30


can be applied elsewhere or in the region of a correspondingly configured blanks unit


69


.




The described device is also suitable for the manufacture and processing of other forms of embodiments of blanks or packets. In addition, the material web for producing the blanks can be prepared externally in various ways. However the ability of the material web to coil must be guaranteed.



Claims
  • 1. A method of manufacturing cigarette packs of the hinge-lid type by folding cardboard blanks (10) in a packaging machine (22), the blanks (10) being prepared by stamping and having folding tabs defined by punched-out lines (18) and by folding lines (16, 17) formed by embossing, said method comprising the steps of:a) positioning, in a region of the packaging machine, an elongated web (19) made of cardboard and wound up as a reel (21); b) applying to the web (19), on one side thereof, printing (29) corresponding to an outer design of a hinge-lid pack, during formation of blanks (10) which are lying adjacent to one another in the web and which have a longitudinal dimension extending transversely to the elongated web (19); c) applying the printing (29) so that it is oriented transversely to the longitudinal direction of the elongated web (19) within each blank, such that printings for a box part (11) and a lid part (12) of each blank follow one another in the transverse direction of the web (19); d) feeding the web (19) in a continuous conveying motion to one of plural blank-forming units (31) of the packaging machine (22); e) within the blank-forming unit (31), first embossing the web (19) to form plural folding lines (16, 17) of the blanks (10) to be produced, said plural folding lines comprising longitudinal folding lines (16) running transverse to the longitudinal direction of the web (19) and transverse folding lines (17) running in the direction of the web (19); f) then, making punched-out lines (18) in the web (19) to form folding tabs and, at the same time, a transverse severing cut (32) for separating each blank (10) from the web (19); g) choosing the web (19) to be greater in width than the longitudinal dimension of the blanks (10), producing contours of the blanks (10) on both longitudinal edges of the web (19) by contoured longitudinal cuts (34, 35), and cutting off corresponding residual pieces (61, 62) of the web while the punched-out lines (18) are made; h) then, removing the blanks (10), from the web; i) feeding the removed blanks (10) to a collecting station within which piles (23) of blanks are formed from successively incoming blanks (10); and j) then, feeding the piles (23) of blanks to the packaging machine (22).
  • 2. The method according to claim 1, wherein before it is fed to the blank-forming unit (31), the web (19) drawn off a reel (21, 26) is subjected to counter-shaping in a decurling unit (65) to remove from the web (19) or blanks (10) a curvature caused by the coiling of the web on reels (21, 26).
  • 3. A method of manufacturing cigarette packs of the hinge-lid type by folding cardboard blanks (10) in a packaging machine (22), the blanks (10) being prepared by stamping and having folding tabs defined by punched-out lines (18) and by folding lines (16, 17) formed by embossing, said method comprising the steps of:a) positioning, in a region of the packaging machine, an elongated web (19) made of cardboard and wound up as a reel (21); b) applying to the web (19), on one side thereof, printing (29) corresponding to an outer design of a hinge-lid pack, during formation of blanks (10) which are lying adjacent to one another in the web and which have a longitudinal dimension extending transversely to the elongated web (19); c) applying the printing (29) so that it is oriented transversely to the longitudinal direction of the elongated web (19) within each blank, such that printings for a box part (11) and a lid part (12) of each blank follow one another in the transverse direction of the web (19); d) feeding the web (19) in a continuous conveying motion to one of plural blank-forming units (31) of the packaging machine (22); e) within the blank-forming unit (69), first embossing the web (19) to form plural folding lines (16, 17) of the blanks (10) to be produced, said plural folding lines comprising longitudinal folding lines (16) running transverse to the longitudinal direction of the web (19) and transverse folding lines (17) running in the direction of the web (19); f) thereafter, making punched-out lines (18) in the web (19) to form folding tabs and, at the same time, a transverse severing cut (32) which is made in such a way that residual web connections (71) remain between adjacent blanks (10), thus resulting in a web (70) of joined blanks (10); g) choosing the web (19) to be greater in width than the longitudinal dimension of the blanks (10), producing contours of the blanks (10) on both longitudinal edges of the web (19) by contoured longitudinal cuts (34, 35), and cutting off corresponding residual pieces (61, 62) of the web while the punched-out lines (18) are made; and h) feeding the web of blanks (70), formed from connected blanks (10) in a region of the blanks-forming unit (69), to a severance assembly (72) where the blanks (10) are separated from the web (70); and i) directly feeding the blanks separated from the web (70) to a rotary folding unit (74) of the packaging machine (22).
  • 4. The method according to claim 3, wherein the blanks are separated from the web (70) in pairs of blanks (73), and further comprising the steps of:feeding the pairs of blanks (73) to the rotary folding unit (74); and severing the pairs of blanks (73) from one another when the blanks (10) are fed into the rotary folding unit (74).
Priority Claims (1)
Number Date Country Kind
197 26 324 Jun 1997 DE
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