EP2653402B1 - Bag provided with a bag base - Google Patents

Description

The invention relates to a bag, according to the preamble of claim 1, formed from a portion of a sack width defining tubular jacket wall from which at least one end of the section by means of Bodeneckeinschlägen and laid over the Bodeneneckeinschläge bottom side envelopes a bottom is placed and glued, the filled Condition of the bag has a rectangular shape with a length of the bottom bounding short side edges and a width of the bottom bounding long side edges, wherein parts of the Bodeneneckeinschläge extend from the short side edges of the bottom as narrow bottom flaps in the region of the bottom over which the bottom side envelopes are folded from the long side edges of the bottom as wide bottom flaps, which overlap each other in the direction of the width of the bottom and are glued together, and wherein a rectangular ground cover sheet with the length and the width of the bottom of the geb glued to the educated floor.

Such generic bags are known in many embodiments. They can be made of different materials. The most commonly used material for these sacks is paper, which is used as kraft paper for large sacks that need to take up more weight. These bags can be single-layered or multi-layered. For multi-ply paper bags, it is possible to make a layer of plastic film to give the bag some moisture immunity. Since paper bags are compostable, it is preferable for the inlaid Plastic film also compostable material to use, so to produce the plastic film of a biodegradable plastic. In individual cases, it may also be useful to combine the paper layers with a metallic foil, for example an aluminum foil.

It is also possible to produce the bags of the type mentioned above completely from a plastic film, wherein bonding operations can also be performed by welding.

The bottom of the generic bags may be formed in a known manner as a cross-bottom when it is folded from a flat-lying tubular jacket wall with only one fold line at the two longitudinal edges of the section. If, however, the tubular jacket wall is formed with gussets, the result of the folding of the bottom is a block or block bottom. The block or block bottom we made in a rectangular shape, while the rectangular shape of the bottom results in a cross bottom only by the filling of the bag by parts of the Bodeneneckeinschläge to the shell wall and the floor by the parts of the Bodeneneckeinschläge that the narrow bottom flaps and the wide bottom flaps form, and the bottom side envelopes is formed. The parallel fold lines of the narrow bottom flap form short side edges of the bottom and the parallel fold lines of the wide bottom flaps the long side edges of the bottom, the long side edges are perpendicular to the short side edges.

To increase the dimensional stability, but also the load resistance of the soil, a rectangular ground cover sheet is glued to the bottom formed by the bottom flaps. The bottom cover sheet has a length and a width which corresponds to the length and the width of the bottom, wherein for the function of the bottom cover sheet and the production accuracy, in particular for paper sacks, significant tolerance deviations in the dimensions the ground cover sheet are acceptable to the dimensions of the ground when the ground cover sheet substantially covers the ground and has sufficient bonding surfaces in the region of all bottom flaps.

A bag according to the invention may have such a bottom at one end of the portion of the casing wall or at both ends. If the bottom is formed on one side, an open bag for filling, which is closed after filling in a known manner, for example by sewing, welding, gluing.

For higher filling weights provided bags, such as cement bags, are usually made with both sides formed soils of the type mentioned, for filling the bag one of the floors is glued so that on one side on one floor an opening between a narrow bottom flap and the two overlapping broad Bottom flaps forms, in which a filler neck of a filling machine is retractable to fill the bag with flowable medium. After filling, the opening closes automatically due to the load with the contents, so that the opening represents a valve opening. For trouble-free automatic operation of the filling process, it is customary to insert into the valve opening of the bottom formed a valve insert, which may be in the form of a flat reinforcing sheet or in a tubular shape. For a heavily dusty filling material, it may be expedient to form the valve opening hermetically closable after filling, for which numerous methods have become known. For example, it is possible to provide the valve core with a heat sealable or sealable layer so as to close off the valve port by supplying heat and high frequency or ultrasonic waves.

When the filled bag reaches the consumer, it must be able to remove the contents from the bag in a convenient manner. For cement bags, for example, it is common to put the bag on a To put ground and remove the now upper bottom of the bag in that the jacket wall is cut circumferentially below the upper floor with a knife. This method has the disadvantage that is often cut with the cutting of the jacket wall already in the Füllguthöhe, whereby contents fall out of the bag uncontrolled. Furthermore, a metered removal from the top completely open bag is particularly difficult if the filling material has a considerable weight, as is the case for example with cement bags.

It is therefore long been attempted to facilitate the removal of the contents of a closed bag through soils.

By DE 40 10 822 A1 It is known to glue under the wide bottom flaps of a crossbeam a rectangular insert sheet having on its underside in the longitudinal direction of the floor extending tear-resistant Aufreißbänder and is provided on a perpendicular to the tear strips front edge with two incisions on both sides of the tear strips, so as to form an actuating end , The construction is based on the fact that the wide bottom flaps do not overlap with each other but do not cover the strip-shaped area of the insert sheet defined by the tear strips. To complete the floor, a bottom cover sheet is glued, from which protrudes the operating end of the insert sheet on one side. By pulling on the operating end, the tearing tapes cause tearing of a strip-shaped part from the insert sheet as well as a central cutting of the bottom cover sheet. Thereafter, a strip-shaped opening in the width of the torn-off from the insert sheet strip for removal is available. For a complete opening, the bottom flaps must be torn open by releasing adhesive bonds. The construction is also possible with a valve bag into which a tubular filling valve is placed on the opposite side of the crosshead from the operating end. At the construction for opening the bag is disadvantageous that the wide Bottom flaps must have a distance from each other and therefore can not be glued together. The stability of the floor must therefore result from the stability of the insert sheet and in particular the bottom cover sheet. However, these must be rupturable with the tear strips, so that with a high material stability of the bottom cover sheet results in a difficult tearing and easier tearing can be achieved only at the expense of reduced stability of the soil.

By the generic DE-AS 1 105 339 For example, a bag with a cross-bottom is known which has a flat valve insert. The insert sheet is provided on its underside with a tear strip. The wide bottom flaps are folded over each other in an overlapping manner over the insert sheet and are provided with perforation line sections which are arranged one above the other and above the tear strip. The valve insert sheet is equipped with a pull-tab on the side of the bottom flaps. By pulling on the pull-tab, the valve insert and the overlying bottom flaps along the perforation lines can be torn open with the tear tape, resulting in a central opening of the bottom. A ground cover sheet is not provided. A disadvantage of this design is that the valve insert sheet, on the one hand, and the wide bottom flaps, on the other hand, are already loaded with their perforation lines during the filling process, so that inadvertent tearing during the filling process is not ruled out. It must be torn for the tearing process those parts of the soil, namely the wide bottom flaps, which are responsible for the stability of the soil during filling. It follows that a high stability of the soil is not compatible with a good tearability.

A similar problem arises in the DE-AS 1 229 828 known construction, in which the wide bottom flaps are arranged overlapping each other, but are formed by perforation lines for tearing off a central tear flap. Again, the tearing process takes place at the bottom flaps themselves, who are responsible for the stability of the soil during the filling of the bag.

The present invention is therefore based on the object, a bag of the type mentioned in such a way that a comfortable tearing operation in the bottom of the bag is possible without having to weaken the stability of the sack during filling.

The solution of this object is achieved with a bag of the type mentioned in the present invention, the features of claim 1, insbesoudere characterized in that on the underside of the overlapping wide bottom flaps a stretched in the direction of the length of the bottom reinforcing strip is adhered to an actuating end under the bottom face sheet protrudes that the wide bottom flaps are each provided with a tear line, which are parallel to the long side edges of the floor and spaced from each other, which is greater than half the width of the bottom and that the tear lines up to the operating end of the Reinforcement strip facing edge of the respective wide bottom flap so that the reinforcing strip lying between the tear lines parts of the wide bottom flaps are torn off and the bottom cover sheet is removable.

The bag of the invention combines a high stability of the soil during filling with a slight opening possibility for emptying the bag. The stability of the bottom during filling results from the fact that the widthwise tears of the wide bottom flaps are significantly separated from one another and that their opening is unlikely due to the filling pressure of the filling material or due to a filling valve inserted into a valve opening due to the bottom cover sheet glued over it. The opening of the bag according to the invention is carried out by pulling the operating end of the reinforcing strip, which causes a tearing of the tear lines of the bottom flaps, since the tear lines to the edge of the bottom flaps extend, which is adjacent to the operating end. This tear propagation progressing from the edge of the bottom flaps over the length does not substantially oppose the bottom cover sheet, as it may be adhered to the undetached portion of the wide bottom flaps with a narrow strip, and this adhesion is achieved by moving the bottom cover sheet upward with the use of the bottom cover usual glue glue is easily solvable. During the filling process, the ground cover sheet is subjected to forces which have considerable proportions in the plane of the ground cover sheet itself and therefore burden the inherent stability of the ground cover sheet, the bonding of the ground cover sheet to the bottom flaps being subjected to essentially shear. When pulling up the reinforcing strip at its operating end, however, the remaining bonding of the bottom cover sheet is loaded on the possibly remaining parts of the wide bottom flaps perpendicular to the plane of the bottom cover sheet and therefore opens easily. It is essential that the bottom is removed over a large part of its width by the pulling up of the reinforcing strip along the tear lines, so that at most small residual strips remain connected to the jacket wall of the wide bottom flaps, while the bottom over most of its width with the reinforcing strip is demolished.

The bag according to the invention thus provides the full stability of the soil when filling through the overlapping wide bottom flaps of the bottom cover sheet. The tearing process is simple, because with the reinforcing strip of the soil is torn off over most of its width, the tearing is performed by the tear line, at least initially. The tear lines can be formed by any type of material weakening, preferably by perforation lines.

The bag according to the invention can be embodied in all known from the prior art construction variants, so in particular be provided with one or two floors and consist of any material. Especially However, it makes sense the formation of the bag according to the invention as a paper bag, especially kraft paper and preferably as a multi-layer paper bag made of kraft paper. In this case, a plastic layer, preferably made of biodegradable plastic, can be inserted into the plurality of layers of the kraft paper.

The bag according to the invention can be carried out with advantage as a valve bag, wherein in a preferred embodiment, under the wide bottom flaps a valve insert from the opposite end of the operating end of the reinforcing strip is used, wherein the valve insert extends to a maximum of half the length of the bottom.

In a further preferred embodiment, the valve insert, which is preferably designed as a valve tube, extends over less than 1/3 of the length of the floor.

In particular, in the embodiment of the bag according to the invention as a valve bag, it is expedient if the tear lines extend from the edges of the wide bottom flaps facing the operating end of the reinforcing strip to more than half the length of the bottom. The resulting slight weakening of the interconnected bottom flaps by the tear lines does not affect in the area of the valve, ie in the area in which a filler neck of a filling machine can be inserted. The resulting load thus does not act directly on the tear lines.

Corresponding to the length of the tear lines and the length of the reinforcing strip may be limited so that the reinforcing strip extends to a maximum of half the length of the soil. This ensures that a valve insert on the one hand and the reinforcing strip on the other hand do not interfere with each other when placed in the ground.

In a preferred embodiment of the invention, the distance between the tear lines of the wide bottom flaps is two thirds or more of the width of the bottom. The width of the reinforcing strip according to the invention may substantially correspond to the distance between the tear lines of the wide bottom flaps and should be at least ¾ of the distance between the tear lines.

The reinforcing strip is preferably made of kraft paper. It may be useful to provide the reinforcing strip itself, in particular in the region of the operating end, with a tear-resistant band, for example made of plastic, in order to ensure that the actuating end does not break off when the bottom of the bag is torn open.

The bag according to the invention can be torn open completely over the entire length of the bag bottom with the aid of the reinforcing strip. Since this virtually eliminates the entire floor, no further opening procedures are required. For complete rupture of the reinforcing strip does not necessarily extend over the entire length of the soil, but may - as mentioned above - for example, halfway or below already end, because then decrease the expended for the further opening forces and later in the opening process can be absorbed by the wide bottom flaps.

In particular, for dusty materials, it may be useful to make the opening of the bag floor only partially, so as to allow a metered removal of the contents of the bag. In this case, the bag bottom can be opened, for example, about half its length.

The invention will be explained in more detail below with reference to an embodiment shown in the drawing.

The single drawing figure shows in a perspective view schematically a bag according to the invention, which has assumed its cubic shape caused by the filling and is partially open on a bottom side for emptying the bag.

The bag consists of a tubular jacket wall 1, which is folded and glued at its two front ends in each case to a bottom 2, 3, here in the form of cross bottoms. In the illustrated embodiment, the bag is on a lower bottom 2, which is designed as a conventional cross bottom. The bottom 3 located in this position has, on the one hand, a valve opening with a valve insert 4 and, on the other hand, a device 5 according to the invention with which the bottom 3 can be opened for emptying the bag.

The lower floor 2 is bounded in a conventional manner by two long side edges 6 and two short side edges 7. For the preparation of the soil is based on the flat tubular casing wall 1, which is bounded by extending in the longitudinal direction of the bag folding lines 8, which is shown in the figure as a dotted line. Due to the formation of known (not shown) Bodeneckeinschlägen extending over the bag width side walls are folded away from each other and laid over as a bottom side envelopes. After the formation of the cylindrical shape of the jacket wall 1, this results in narrow side flaps 9 hinged to the short side edges 7 and wide bottom flaps 10 hinged to the long side edges 6, which are glued together overlapping each other. The narrow bottom flaps 9 and the wide bottom flaps 10 thus protrude at right angles from the tubular jacket wall 1 angled into the region of the bottom 2 and are thus together glued that they already form a dense bottom 2. Finally, a rectangular bottom cover sheet 11, which essentially has the dimensions of the bottom 2, is glued to the bottom 2. As the drawing figure illustrates, the bottom cover sheet 11 is both with respect to the length and. With respect to the width of the bottom 2 is slightly smaller than the bottom 2 is formed. The upper floor is formed with basically the same construction and consists of narrow bottom flaps 9 and wide bottom flaps 10th

It can be seen from the part of the bottom 3 opened in the drawing figure that the narrow bottom flaps 9 project with a straight, free end edge 12 in the area of the bottom 2 over its entire width. The wide bottom flaps 10, however, have free end edges 13, whose length is significantly smaller than the length of the long side edges 6, from which they go out. The bottom flaps are therefore trapezoidal, because they are connected by triangular pockets with the narrow bottom flaps 9.

As already mentioned, the upper bottom 3 has at one end a valve opening into which the valve insert 4, preferably in the form of a flat tubular paper strip, is inserted. The valve insert extends in the illustrated embodiment over about 1/3 of the length of the bottom 2 and protrudes with its inner edge 14 on the free end edge 12 of the located on this side narrow bottom flaps 9 addition. The valve insert 4 thus defines, with its inner edge 14, the connection between the valve opening of the bottom 3 and a bag interior formed by the tubular jacket wall 1 and the bottom 2, 3.

The upper bottom 3 is on its side opposite the valve insert - with respect to its length. - Provided with the device 5 to open. The device 5 consists of a reinforcing strip 15 which is glued on the bottom of the two wide bottom flaps 10 facing the bag interior. The reinforcing strip 15 extends over the length of the Bodendeckblatts 11 with a protruding end, which thus forms an actuating end 16 which protrudes from the bottom 3 and on which the reinforcing strip 15 can be grasped.

The drawing figure shows that when pulling up the reinforcing strip 15 at the operating end 16 of the bottom is opened by a part of the two wide bottom flaps 10 is torn off along a tear line 17 with the reinforcing strip 15. For example, the tear-open line 17 may be formed as a perforation line which guides the tearing operation of the bottom 3 caused by the reinforcing strip 15. The tear lines can extend over the entire length of the floor (ie the entire bag width). In the illustrated embodiment, however, the tear lines 17 extend over only a portion of the length of the bottom 3, starting from the oblique edges of the wide bottom flaps 2 pointing to the operating end 16 to about half the length of the bottom 3. Thus, the tearing process of the soil 3 by means of the reinforcing strip 15 to about half the length of the bottom 3 through the tear lines 17 and can be continued for a complete opening over the entire length of the bottom 3 without tearing, because of the residual length of the bottom 3 due to the only lower required Tearing forces such a leadership is no longer necessarily needed. As a result, the advantage is achieved that the tear lines 17 do not extend into the region of the valve insert 4. However, this area is stretched by an inserted filler neck and therefore loaded with forces that could cause an opening of the tear line 17. The approximately half the length of the bottom 3 ending tear lines 17 are not immediately acted upon by the opening of the bottom valve, so that a premature weakening of the stability of the bottom 3 is not to get through the inserted filler neck.

In the illustrated embodiment, the width of the reinforcing strip 15 corresponds exactly to the distance between the tear lines 17. This is but not essential. It is only essential that the reinforcing strip 15 has a width such that the tearing of the parts of the wide bottom flaps 10 along the two tear lines 17 initially takes place. It is therefore useful if the width of the reinforcing strip 15 is at least 3/4 of the distance between the tear lines.

Further, in the illustrated embodiment, the length of the reinforcing strip 15 corresponds to the length of the tear lines 17. Again, this is not a necessary feature. Rather, the reinforcing strip 15 may be shorter or longer than the tear lines 17. In general, it will be useful for the reinforcing strip 15 to extend at least 1/4 or 1/3 of the length of the bottom from the operating end 16. In the drawing figure, the bottom 3 is only partially open. By pulling up the narrow bottom flap 9 can thereby create a blind opening that allows a metered emptying of the bag.

For a complete emptying of the bag, it makes sense to make the opening of the bottom 3 over its entire length, so the soil on the entire length by tearing along the tear lines 17 and beyond - including the valve insert 4 - tear. It then creates an opening that corresponds to an open bag with a single cross bottom.

It can be seen that the tear lines 17 are arranged near the long side edges 6, so that after the tearing of the bottom 3 at most narrow edge strips 18 remain, with which the bottom cover sheet 11 was generally glued initially and of which the bottom cover sheet 11 due to the small contact surface is easy and unproblematic deductible when using conventional glue glue. With the reinforcing strip 15 thus the part of the wide bottom flaps 10 is torn off between the tear lines 17 and the bottom cover sheet 11 detaches from the edge strips 18. A tearing Therefore, the bottom cover sheet 11 does not take place, so that the bottom cover sheet 11 does not have to be weakened for a tearing operation, but can cause full stability of the bottom 3. In particular, this makes it possible to form a stable bottom for filling 3, which can be opened with ease of use in a reliable and reproducible manner.

Claims (10)

1. Bag formed from a portion of a tubular, bag-width-defining lateral wall (1), from which, by means of folded-in bottom corners and folded-over bottom sides positioned over the folded-in bottom corners, a bottom (2, 3) is established, and adhesively bonded, at at least one end of the portion, said bottom, in the filled state of the bag, being of rectangular shape with short side edges (7), which delimit a length of the bottom, and long side edges (6), which delimit a width of the bottom, wherein parts of the folded-in bottom corners, starting from the short side edges (7), extend into the region of the bottom (2, 3) in the form of narrow bottom flaps (9), over which the folded-over bottom sides, starting from the long side edges (6) of the bottom (2, 3) are folded in the form of broad bottom flaps (10), which overlap one another, and are adhesively bonded to one another, in the direction of the width of the bottom (2, 3), and wherein a rectangular bottom cover sheet (11) of the length and of the width of the bottom (2, 3) is adhesively bonded to the bottom (2, 3) formed, characterized in that the underside of the broad, overlapping bottom flaps (10) has adhesively bonded to it a reinforcing strip (15), which extends in the direction of the length of the bottom and has an actuating end (16) projecting beneath the bottom cover sheet (11), in that the broad bottom flaps (10) are provided with a respective tear-open line (17), said lines running parallel to the long side edges (6) of the bottom (2, 3) and being spaced apart from one another by a distance which is greater than half the width of the bottom (2, 3), and in that the tear-open lines (17) extend as far as that periphery of the respective broad bottom flap (10) which is oriented towards the actuating end of the reinforcing strip (15), and therefore, by means of the reinforcing strip (15), those parts of the broad bottom flaps (10) which are located between the tear-open lines (17) can be torn off and the bottom cover sheet (11) can be removed.
2. Bag according to Claim 1, characterized in that the tear-open lines (17) are spaced apart from the long side edges (6), and in that, by means of the reinforcing strip (15), the bottom cover sheet (11) can be pulled off from the peripheral strips (18) of the broad bottom flaps (10), said peripheral strips remaining from the once the parts of the broad bottom flaps (10) have been torn off.
3. Bag according to Claim 1 or 2, characterized in that a valve insert (4) is inserted beneath the broad bottom flaps (10) from the peripheries located opposite the actuating end (16) of the reinforcing strip (15), said valve insert extending not more than over half the length of the bottom (3).
4. Bag according to Claim 3, characterized in that the valve insert (4) extends over less than 1/3 of the length of the bottom (3).
5. Bag according to one of Claims 1 to 4, characterized in that the tear-open lines (17) extend not more than over approximately half the length of the bottom (3) from those peripheries of the broad bottom flaps (10) which are oriented towards the actuating end (16) of the reinforcing strip (15).
6. Bag according to one of Claims 1 to 5, characterized in that the reinforcing strip extends not more than halfway along the length of the bottom (3).
7. Bag according to one of Claims 1 to 6, characterized in that the distance between the tear-open lines (17) of the broad bottom flaps (10) is 2/3 or more of the width of the bottom (3).
8. Bag according to one of Claims 1 to 7, characterized in that the reinforcing strip (15) has a width of at least 3/4 of the distance between the tear-open lines (17) of the broad bottom flaps (10).
9. Bag according to one of Claims 1 to 8, characterized in that the reinforcing strip consists of kraft paper.
10. Method of opening a bag according to one of Claims 1 to 9, characterized in that, by virtue of the actuating end (16) of the reinforcing strip (15) being subjected to pulling action, only over part of the length of the bottom (3), an emptying opening for the bag is produced in the region of the bottom (3).

Images