This application claims the benefit under 35 USC 119 of German patent application number 10 2008 007 754.2 having a filing date of 5 Feb. 2008, which is incorporated herein in its entirety by this reference.
The invention relates to a process for producing tobacco bags from sheet material having a pocket which is bounded or closed by lateral seams—side seams— and which has an opening with a closure flap, in particular a fold-over flap, it being the case that a continuous sheet-material web is folded over in the longitudinal direction to form a web leg, is then provided with transversely directed connecting seams in the region of the web leg and, finally, the bags are severed from the web, by transversely directed severing cuts in the region of the double-width connecting seams, filled and closed, and that separate blanks, in particular closure means such as tape, touch-and-close fastener strips and/or printing carriers or coupons and/or stickers for fixing inserts, are applied to the bag by adhesive bonding. The invention also relates to an apparatus for carrying out the process.
The bags in question here serve for accommodating a portion of cut tobacco. Once the pocket has been filled, the fold-over flap is folded around the pocket and fixed on a rear pocket wall by a retaining means, in particular by a tape. The issue here is that of improved production of bags of this or a similar type along with better performance of the machines used.
Accordingly, the object of the invention is to improve the production of (tobacco) bags of the configuration mentioned in the introduction, or of a similar configuration, in respect of performance without quality being adversely affected.
In order to achieve this object, the process according to the invention is characterized in that the separate blank or blanks is or are applied to the bag, in particular to the fold-over flap and/or to a front pocket wall, prior to the bag being filled, and in that the bag is then filled and closed.
In particular, the abovementioned blanks are applied to the (sheet-material) web, namely fixed by adhesive bonding, in the relative position appropriate for the finished bag. Thereafter, the bags having the respectively necessary blanks are severed from the web by transversely directed severing cuts. The web is expediently first of all folded in longitudinal direction to form the web leg. Thereafter, the transversely directed connecting seams are provided and then adhesive bonding is used to fasten the separate blanks on the web prepared in this way.
The apparatus according to the invention is provided with a folding station for continuously folding over the web to form the web leg during continuous transportation, with a downstream sealing station for providing the transversely directed connecting seams, with a blank station/application station for applying the respectively necessary blanks, in particular for applying a tape for each bag, with a downstream severing station for severing the bags from the web and, finally, with a filling and closing station. The design of the blank station and of the downstream severing station is special.
Details of the process and of the apparatus are explained more specifically hereinbelow with reference to the drawings, in which:
The invention deals predominantly with the production, filling and completion of bags 10 made of thin packaging material, in particular (thermally sealable) sheet material. The bag 10 comprises a single piece, in this case rectangular, elongate blank which, on account of a leg being folded over, forms a pocket 11 for the pack contents, the pocket having a front pocket wall 12 and a rear pocket wall 13. These abutting regions of the blank are connected to one another by thermal welding or adhesive bonding, to be precise by side seams 14, 15. An opening 16 allows the pocket 11 to be filled and the contents to be removed. The rear pocket wall 13 is extended beyond the opening 16 and forms a closure flap or a fold-over flap 17. If the pocket 11 has been filled and closed, if appropriate, in the region of the opening 16 by closing strips, this fold-over flap is folded around the pocket such that an end region of the fold-over flap 17 butts against the rear pocket wall 13 and is connected thereto.
The bag 10 is provided with applications or blanks fastened by adhesive bonding, if appropriate also by thermal sealing (welding). In the case of the present example, as closure means of the bag 10 a tape 18 is applied—approximately centrally— to the free periphery of the fold-over flap 17. The strip-like closure means has a permanent-adhesive coating on one side and an adhesive-free grip tab 19 at the free end region.
Also in the case of this example, a printing carrier or a coupon 20 (folded a number of times), in other words an advertising or information carrier, is applied to the bag 10. The coupon 20 is fixed, approximately centrally, on the inside of the fold-over flap 17 by adhesive bonding.
A device for retaining inserts, to be precise a rectangular retaining piece, namely a sticker 21, is also applied to the bag 10. This sticker has an adhesive-bonding surface on both sides, that is to say for fastening on the bag 10 and for applying inserts, in particular a pack with cigarette paper. The sticker 21 here is applied to the outside of the front pocket wall 12.
One special feature consists in the fact that the abovementioned applications 18, 20, 21 are applied to the bag 10 before the latter is filled and closed. The finished, but unfilled bags 10 are created by severing from a continuous (sheet-)material web 22. The latter is provided, during continuous transportation, in a folding station 23, with a longitudinal fold, namely with a continuous web leg 24, which forms the front pocket wall 12 of the bag 10. Thereafter, transversely directed connecting seams 25 are provided in the region of the folded sheet-material web 22 in a sealing station 26. The connecting seams 25 are double the width of the side seams 14, 15. In a downstream severing station 27, the bags 10 according to
The separate blanks 18, 20, 21 are applied to the sheet-material web 22 in an appropriate position. An application station 30 is preferably positioned between the sealing station 26 and the severing station 27. Accordingly, the blanks, at least the tape 18, are/is applied to the sheet-material web 22 once the pockets 11 have been defined by the connecting seams 25.
An apparatus for producing, filling and closing the bags 10 is characterized by a compact grouping of subassemblies. The (non-folded) sheet-material web 22 is drawn off from a reel 31 with a horizontal axis of rotation and fed to the folding station 23 via a compensating pendulum arrangement 32. A stationary, essentially triangular folding device 33 (folding diverter) forms the web leg 24 during continuous transportation of the sheet-material web 22. At the same time, the sheet-material web 22 is deflected through 900 into a main conveying direction. The compensating pendulum arrangement 32 serves to compensate for different rotational speeds of the reel 31 and to provide for a constant, continuous conveying speed in the region of the folding station 23.
The sheet-material web 22 prepared in this way is directed, via deflecting and drive rollers, through a sealing subassembly 34 in order for the connecting seams 25 to be provided. The sealing subassembly 34 is arranged in an upright state. The sheet-material web 22 is introduced into the sealing subassembly 34 at a top end and, once the connecting seams 25 have been provided by means of transversely directed and transversely movable sealing and/or welding devices, is guided out of the sealing subassembly 34 at the bottom end. The sheet-material web 22 is then guided further upwards and directed through a further compensating pendulum arrangement 35. In the region of the sealing subassembly 24, the web 22 is driven cyclically. The downstream stations are likewise geared to cyclic conveying of the sheet-material web 22, but with conveying cycles which differ from that in the region of the sealing subassembly 34. These different movements are compensated for by the compensating pendulum arrangement 35.
The application station 30 is equipped with an application subassembly, for example a tape subassembly 36, of which an advantageous exemplary embodiment is shown in
In the case of the example according
In order for the tape 18 to be applied correctly to the sheet-material web 22, the application roller 37 is extended axially beyond the region of the bag 10, or of the fold-over flap 17, and is designed with a special peripheral region 44 intended for accommodating or supporting the projecting region of the tape 18. The latter has its free adhesive-bonding side butting against the peripheral region 44, which exhibits a low retaining force and is provided with pointed or sharp-edged protrusions 45, in particular encircling ribs. The adhesive-bonding surface of the tape 18 butts in an easily releasable manner against the points. The adhesive-free grip tab 19 butts against a cylindrical peripheral surface of the application roller 37 and is retained here by radial suction bores 46, that is to say by negative pressure.
The pressure-exerting roller 42, which is located opposite, is likewise provided with means for retaining the tape 18 until it is transferred to the application roller 37, that is to say it is provided with a plurality of radial suction bores 47 connected to a negative-pressure source.
In the bottom region of the application roller 37, the sheet-material web 22 provided with the tapes 18 (or other blanks) is transported further in a horizontal plane and fed to a severing device 48 of the severing station 27. The sheet-material web 22 is deposited on a conveyor, in particular on an intermediate conveyor 48 designed as a suction belt. This intermediate conveyor guides the sheet-material web 22 right up to a severing plane. The design of the intermediate conveyor 48 is special (
In order to ensure reliable guidance of the tape 18, the application roller 37 is followed, above the receiving conveyor 48, by a strip conveyor which acts in the region of the grip tab 19 of the tape 18. This is a round belt 51, which has a bottom conveying strand butting against the grip tab 19. The conveyor or round belt 51 extends from a region directly adjacent to the application roller 37 into the region of a continuing conveyor for the severed bags 10, namely into the region above a bag conveyor 62. The round belt 51 runs—in the lateral region—through the severing station 27.
Fitted in a stationary manner alongside the round belt 51, above the receiving conveyor 48, is a supporting device for the sheet-material web 22, namely a guide component 52 which tapers in a wedge-shaped manner on the side directed towards the application roller 37 and, opposite this, extends precisely as far as the severing plane. The planar or plate-like guide component 52 prevents the sheet-material web 22 from warping once it has left the application roller 37.
A severing device acts cyclically in the region of the severing station 27 and executes a severing cut, approximately centrally in the region of the connecting seam 25, transversely over the entire width of the sheet-material web 22. The severing device comprises a severing blade 53 which is mounted in a pivotable manner outside the region of the sheet-material web 22. Accordingly the severing blade 53 executes a severing cut as a pivoting movement made in an upright plane. The severing blade can be pivoted about a pivot bearing 54 which is mounted preferably in a displaceable manner on a carrying wall 55 of the machine framework. An actuating gear mechanism provides for the coordinated movement of the severing blade 53 up and down. For this purpose, an actuating arm 56 with a contact roller can be actuated by a revolving cam plate 57. The severing blade 53 and actuating arm 56 act as a two-armed lever. The movement amplitude of the severing blade 53 is such that an entire severing cut is executed. An abutment blade 58 interacts with the severing blade 53. This abutment blade is designed as a fixed, transversely directed cutting component. The severing blade 53 and abutment blade 58 together give rise to a scissors-like cutting operation by way of the pivoting movement of the severing blade 53. The abutment blade 58 is arranged beneath the plane of the sheet-material web 22.
The severing blade 53 or the pivot bearing 54 is fitted in a displaceable manner on the carrying wall 55, in order that the cutting or severing plane can be adjusted. This makes it possible to produce bags 10 of different widths. The abutment blade 58 is displaced along therewith as the unit. For this purpose, the pivot bearing 54 is fitted on a carrier 60 which is mounted in a displaceable manner, in particular on the carrying wall 55. The severing blade 53 or the pivot bearing 54 is forced, by the pressure of a spring 61, in the direction of the abutment blade 58, and this means that a precise cut is always ensured.
The severed bags (including tape 18) are received by a connection conveyor, namely the bag conveyor 62. The latter transports the bags 10, at a spacing apart from one another, into the region of the transfer station 28. In the latter, the bags 10 are gripped one after the other and transferred to a filling and closing subassembly, namely to a bag turret 63. The arrangement is such that a plurality of, in the present case four, bags 10 are simultaneously positioned on the bag conveyor 62, gripped and transferred to the bag turret 63. The filled and closed bags are deposited on a removal conveyor 64 and removed.
For the displacement of the cutting or severing plane in the severing station 27, it is also possible to adjust the bag conveyor 62 or an initial region which is directed towards the severing station 27. The bag conveyor 62 is designed as a suction conveyor for fixing the bags 10 to a sufficient extent on a top strand 80. Arranged beneath the same is a suction box 81, for applying negative pressure to the top strand 80. The suction box 81 is designed telescopically, that is to say with a telescoping box 82, in order to provide for displacement of the accommodating end of the bag conveyor 62. This telescoping box extends as far as a top deflecting roller 83 for the top strand 80. The relative positioning always remains the same since the telescoping box 82 enters into the suction box 81 to a more or less great extent. The telescoping box 82 is also designed as a negative-pressure source for the top strand 80, and this ensures that the bags 10 are secured as far as the deflecting roller 83. Furthermore, the belt of the bag conveyor 62 is guided around a compensating roller 84, which in the case of the present exemplary embodiment is connected to the telescoping box 82, but can always be moved therewith. This means that the tensioning in the belt of the bag conveyor 62 is maintained even upon displacement of the accommodating end. A further deflecting roller 85 is provided beneath the compensating roller in order to guide the belt into the bottom strand and receive it therefrom.
The application station 30 may be designed such that, rather than just one closure means (tape 18), further blanks can be applied to the bags 10 or the prepared sheet-material web 22. In the case of the exemplary embodiment according to
It is also the case here that the application subassembly 36 is assigned to an application roller 37, over the circumference of which is transported the sheet-material web 22 which has been prepared in the manner described. The tapes 18 are severed from a continuous tape web 65 by transversely directed severing cuts and positioned precisely, by a feed roller 66, on the sheet-material web 22, as described in conjunction with
A coupon subassembly 69 and sticker subassembly 70 are arranged upstream of the application subassembly 36 as seen in the transporting direction. The subassemblies 69 and/or 70 are/is positioned in the region of a horizontal web portion 71, above the application subassembly 36. The subassemblies 69 and 70 are of largely corresponding design. The coupons 20, on the one hand, and the stickers 21, on the other hand, are respectively arranged on a carrier web 72. This is drawn off from a roll 73. In a manner analogous to the exemplary embodiment according to
The sheet-material web 22 is transported in the region of the subassemblies 69, 70 such that the front pocket wall 12 or the web leg 24 is directed upwards, that is to say is exposed. In the case of the arrangement of the blanks 20, 21 on the bag which is used by way of example (
The subassemblies 69, 70 operate with cyclic advancement of the sheet-material web 22. As an alternative to the configuration according to
It is generally the case, in respect of the movement characteristics of the sheet-material web 22, that, in a tape subassembly 36 with a rotating application device, the sheet-material web is transported as the tape 18 is being applied, but is otherwise halted cyclically in order for the severing cut to be executed in the region of the severing station 27.
Number | Date | Country | Kind |
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102008007754.2 | Feb 2008 | DE | national |