METHOD AND DEVICE FOR FILLING FLEXIBLE TUBULAR BAG PACKAGING

Abstract

A method can fill a flexible tubular-bag packaging with a filler that contains a coarse material and can close the tubular-bag packaging. The method includes: (a) introducing a filler into a tube, (b) displacing the filler out of a closure zone of the tube, (C) pinching-off the tube in the closure zone, (d) substance-to-substance joining of oppositely disposed regions of the tube in the closure zone to form closed ends of successive tubular bags, (e) separating a tubular bag from the tube, such that two ends of successive tubular bags produced by cutting of the tube are each closed by substance-to-substance bonding.

Claims

1: A method for filling a flexible tubular-bag packaging with a filler that contains a coarse material and for closing the tubular-bag packaging, the method comprising: (a) introducing a filler into a tube, (b) displacing the filler out of a closure zone of the tube, (c) pinching-off the tube in the closure zone, (d) substance-to-substance joining of oppositely disposed regions of the tube in the closure zone to form closed ends of successive tubular bags, and (e) separating a tubular bag from the tube, such that two ends of successive tubular bags produced by cutting of the tube are each closed by substance-to-substance bonding.

2: The method according to claim 1, wherein the substance-to-substance joining takes place by welding.

3: The method according to claim 1, wherein at least four linear joint zones are created next to one another over the entire closure zone.

4: The method according to claim 3, wherein the linear joint zones are respectively formed as one contiguous joint zone.

5: The method according to claim 3, wherein cutting of the tube is performed between two linear joint zones.

6: The method according to claim 1, wherein said pinching-off takes place in the joint zones, and, between the joint zones, regions for receiving grains of the coarse material are created, into which grains present in the joint zone are pushed by displacement.

7: The method according to claim 1, wherein a rotationally driven wheel, which comprises teeth, is present at the side of the tube and carries out said displacing, pinching-off, and substance-to-substance joining of the regions of the tube, wherein the rotationally driven wheel carries out separation of a filled, closed tubular bag from the tube, and wherein appendages oriented substantially in the direction of the axis of rotation are formed on the outside of the teeth.

8: An apparatus for filling flexible tubular-bag packaging with a filler that contains a coarse material and for closing the tubular-bag packaging, the apparatus comprising: (a) a filling device for introducing a filler into a tube, (b) a device for pinching-off the tube in a closure zone, (c) a device for substance-to-substance joining of oppositely disposed regions of the tube in the closure zone, and (d) a cutting device for separation of a filled, closed tubular bag from the tube in the region of the closure zone, such that the ends of successive tubular-bag packaging produced by cutting the tube are each closed by substance-to-substance bonding.

9: apparatus according to claim 8, wherein a first rotationally driven wheel, which comprises teeth, is disposed at the side of the tube, wherein a device for displacement, and the devices for pinching-off and for substance-to-substance joining are formed on the radial outsides of the teeth, and wherein the tube can be pinched between the outside of a tooth and a counter-bracing device situated on the opposite side of the tube.

10: The apparatus according to claim 9, wherein the counter-bracing device is formed by a second, rotationally mounted toothed wheel and the first and second toothed wheels can be driven synchronously in opposite directions of revolution, so that the tube is pinched between outside regions of oppositely disposed teeth.

11: The apparatus according to claim 10, wherein at least two linear, radial appendages oriented substantially parallel to the axis of rotation are provided on the outside regions to form the device for pinching-off the tube.

12: The apparatus according to claim 11, wherein at least four radial appendages, oriented next to one another, are present on one outer side for pinching-off during a pinching-off process, and wherein the spacing of the appendages is at least 1 mm.

13: The apparatus according to claim 11, wherein the at least two appendages have sharply tapering or rounded profiles in radial sectional view through the first rotationally driven wheel.

14: The apparatus according to claim 9, wherein the cutting device is integrated in the teeth.

15: The apparatus according to claim 9, wherein the device for substance-to-substance joining is formed by the wheel and the counter-bracing device.

16: The apparatus according to claim 11, wherein the at least two appendages form the welding contacts.

17: The method according to claim 1, wherein the substance-to-substance joining takes place by an ultrasonic welding method, and wherein said pinching-off and said substance-to-substance joining occur simultaneously.

18: The apparatus according to claim 9, wherein the cutting device is in the form of at least one radially extendable knife and is integrated in the teeth.

19: The apparatus according to claim 9, wherein the device for substance-to-substance joining is formed by the wheel and the counter-bracing device, and wherein the first wheel is formed as a sonotrode or welding jaw and the counter-bracing device is formed as an anvil or welding jaw.

20: The apparatus according to claim 11, wherein at least four radial appendages, oriented next to one another, are present on one outer side for pinching-off during a pinching-off process, and wherein the spacing of the appendages is at least 2 mm.

Description

[0046] The invention will be explained in more detail hereinafter on the basis of the attached drawings, wherein;

[0047] FIG. 1 shows the inventive apparatus for performing the inventive method in a schematic side view;

[0048] FIG. 2 shows an enlarged section of the apparatus according to FIG. 1;

[0049] FIG. 3 shows a detail of the apparatus from FIG. 1 according to one alternative; and

[0050] FIG. 4 shows two tubular-bag packaging produced by the inventive apparatus while applying the inventive method.

[0051] FIG. 1 shows an example of an apparatus for filling and closing of tubular-bag packaging.

[0052] Via a tubular filling device, a filler 12 containing coarse, sand-like material is introduced into a flexible, film-like tube 14, which represents a tubular-bag packaging for the filler.

[0053] In general, any kind of fillers, especially one-component or multicomponent substances, especially for the construction industry, are to be understood as filler 12.

[0054] Tube 14 is traveling from right to left in FIG. 1 and is closed at its respective ends by an apparatus provided with a toothed wheel 16 rotating in the direction of the arrow, Means for pinching-off tube 14, by pinching-off tube 14 at the front and rear end, means for substance-to-substance joining of portions of tube 14 disposed opposite one another and one on top of the other, and finally cutting devices 22 for separating the filled and then closed tubular bag 24 are provided on teeth 20, which in the present case are rounded, of toothed wheel 16. The respective details will be explained more precisely hereinafter.

[0055] A so-called counter-bracing means 26, which may be constructed to be stationary and may be constructed as a rounded web oriented transverse to the transport direction of tube 14 and in axial direction of toothed wheel 16, cooperates with toothed wheel 16. Alternatively to this, it is likewise possible to construct counter-bracing means 26 as a rotating toothed wheel.

[0056] If counter-bracing means 26 is a non-rotating part, it may preferably be moved toward and away from the shaft of the toothed wheel, vertically according to FIG. 1, when tube 14 must be cycled onward.

[0057] FIG. 1 shows that the already filled tubular bag 24 is pinched off at the left of toothed wheel 16 by the tooth bearing on counter-bracing means 26. Thereby the tubular-bag packaging to be filled is simultaneously closed at the right of toothed wheel 16.

[0058] FIG. 2 shows one of the teeth 20 in detail. A cutting device 22 in the form of a radially movable knife 28, which is mounted in a corresponding slot in the tooth and which can be moved radially outward and inward by an electromechanical, hydraulic or pneumatic drive unit, is seated in each tooth 20.

[0059] Each rounded tooth 20 has several portions in the region of its tooth tip. Portions 32, 34, which form the portions of each tooth 20 pointing farthest radially outward and which pinch off tube 14 between them and counter-bracing means 26, are situated laterally next to the outlet slit for knife 28. Thus these portions 32, 34 form means for pinching-off the tube.

[0060] The region of tube 14 in which pinching-off takes place forms a so-called closure zone.

[0061] A region 30, which is not used directly for pinching-off tube 14, is situated adjoining portion 32. During rotation of toothed wheel 16, however, toothed wheel 16 displaces the grains of the material in filler 12 present in region 30 out of the later joint zones, so that no grains are situated in the joint zones. The joint zones are those oppositely disposed regions of the tubular-bag packaging that are joined to one another by substance-to-substance bonding. Thereby region 30 of tooth 20 forms a means for displacing the fillers out of the closure zones of tube 14.

[0062] In FIG. 3, the region of toothed wheel 16 and of counter-bracing means 26 shown as I in FIG. 1 is further enlarged and illustrated in an alternative variant.

[0063] Several web-like appendages oriented in axial direction of toothed wheel 16 are provided in portions 32 and 34. Of those, appendages 36 are sharply tapered and appendages 38 are rounded. These appendages 36, 38 end at counter-bracing means 26 not in a planar face but instead lead to a kind of line contact with counter-bracing means 26. While toothed gear 16 and counter-bracing means 26 are approaching one another, grains present in the closure zone are not squeezed but instead are displaced laterally, either into the intermediate spaces between appendages 36, 38 or into the bags. This rules out the possibility that grains can be situated between counter-bracing means 26 and the radial ends of appendages 36, 38. Thus contact of oppositely disposed regions of the film between appendages 36, 38 and counter-bracing means 26 is guaranteed, so that the joint zones are formed here.

[0064] The distance to be measured in transportation direction of the film between adjacent appendages 36, 38 is at least 1 mm, preferably at least 2 mm, so that sufficient space is available to receive the grains in the filler.

[0065] This variant does not necessarily also need a separate region 30 for displacement of the filler out of the joint zones. The corresponding means for displacement may also be formed by the special geometries of appendages 36, 38.

[0066] FIG. 3 additionally shows recess 40, into which knife 28 can plunge, in order to sever the film.

[0067] Toothed wheel 16, or stated more accurately appendages 36, 38, is able to act as a welding jaw or ultrasonic sonotrode, so that it has a multiple function.

[0068] The mode of operation of the apparatus will be explained hereinafter. In the embodiment illustrated in FIG. 1, toothed wheel 16 has been rotated precisely into the position illustrated in FIG. 1, so that appendages 36, 38 or, with reference to the simplified embodiment according to FIG. 2, press the regions of the shell surface disposed opposite portions 32, 34 against one another, and do so between themselves and counter-bracing means 26.

[0069] As an example, counter-bracing means 26 may be vertically positionable or disposed in stationary manner, so that tube 14 is pulled along counter-bracing means 26 during the movement of toothed wheel 16. However, when region 30 or appendages 36, 38 are moved toward counter-bracing means 26, the grains present in this region of tube 14 are displaced laterally, specifically into adjacent regions, for example between appendages 36, 38. This is followed by closing of the tube, when portions 32, 34 or appendages 36, 38 are in their final position, in which they separate tube 14 between themselves and counter-bracing means 26.

[0070] Then the welding jaw or the ultrasonic sonotrode is activated, so that the regions of tube 14 disposed on top of one another are welded to one another. As shown in FIG. 4, several parallel linear joint zones 46 are obtained, which together define closure zone 48.

[0071] In this connection, successive tubular bags 24 are closed simultaneously at their facing ends.

[0072] Then knife 28 is extended and separates the two tubular bags 24 from one another.

[0073] Preferably, as shown in FIG. 4, several joint zones, which in the illustrated exemplary embodiment are formed by appendages 36, 38 on each side, are provided alongside the cut line. Thus additional closure safety is ensured.

[0074] In the embodiment illustrated in FIG. 3, three joint zones 46 at the right of knife 28 are formed by appendages 36, 38, whereas two appendages 36, 38 and two joint zones are present at the left of knife 28.