Package

Abstract

A package for feed material comprising a package body consisting of sheet plastic and a de-aerating means having a de-aerating area, where an inner sheet layer and an outer sheet layer are provided to form a de-aeration channel to connect an inner de-aeration opening in connection with the interior of the package body with at least one outer de-aeration opening in connection with the environment of the package body. The de-aeration channel comprises two separate chambers interconnected through an overflow opening wherein the inner de-aeration opening is provided at the first chamber and the outer de-aeration opening, at the second chamber so as to increase water tightness.

Description

CROSS-REFERENCES TO RELATED APPLICATIONS

This application claims the priority of German Patent Application, Serial No. 10 2006 022 815.4, filed May 13, 2006, pursuant to 35 U.S.C. 119(a)-(d), the content of which is incorporated herein by reference in its entirety as if fully set forth herein.

BACKGROUND OF THE INVENTION

The present invention relates to a package for feed material, in particular a bag and preferably a gusseted bag, consisting of sheet plastic to protect the feed material from moisture and comprising a de-aerating means for excess air to escape from the package.

Nothing in the following discussion of the state of the art is to be construed as an admission of prior art.

After filling bulk material into bags, the air trapped in the bag will escape over time such that in the absence of a de-aerating means, air bubbles may form at the top surface of the package. Such air bubbles are an impediment to the stacking capability and the bags can also relatively easily split or tear open at these places under pressure load. It is therefore reasonable to de-aerate plastic bags.

German document DE 10 2004 026 538 A1 discloses a plastic bag for filling with bulk material having a multi-layer overlapping region provided in the top surface of the bag, comprising a de-aeration channel between first de-aeration openings in the inner plastic layer and second de-aeration openings in the outer plastic layer. The first de-aeration openings positioned in the center of the bag surface in the inner plastic layer are staggered in respect of the height relative to the second de-aeration openings in the outer plastic layer. Although the vertical staggering of the de-aeration openings toward the inside and toward the outside of the bag serves to prevent moisture from entering for some time, the distance between the outer and the inner de-aeration openings is less than half the bag length, the effect of sealing is limited in time.

It would therefore be desirable and advantageous to provide an improved package to obviate prior art shortcomings and to allow de-aerating the bag while also increasing protection from entering moisture.

SUMMARY OF THE INVENTION

According to one aspect of the present invention, a package for feed material according to the invention is in particular configured as a bag, comprising at least one package body of a sheet made of plastic and at least one de-aerating means with at least one de-aerating area where an inner sheet layer and an outer sheet layer are provided. The inner sheet layer and outer sheet layer form a de-aeration channel to connect at least one inner de-aeration opening that is in connection with the interior of the package body with at least one outer de-aeration opening that is in connection with the environment of the package body. The de-aeration channel comprises at least two separate chambers being in connection with one another through at least one overflow opening wherein the inner de-aeration opening is provided at the first chamber and the outer de-aeration opening, at the second chamber so as to increase water tightness.

The package according to the invention comprises gussets in particular when empty, being provided with welding corners in particular in the region of the gussets. In this way a rectangular shape and good stacking capability of the filled package is ensured.

The invention has numerous advantages. One significant advantage is that moisture must cover a considerably longer distance before entering into the package interior since the de-aeration channel comprises a first chamber and a second chamber. Any moisture entering must thus firstly travel the length of the second chamber, travel from the second chamber through the overflow opening to enter the first chamber and then travel the length of the first chamber before the entering moisture reaches the package interior. In this way, the protection achieved from moisture is higher than had been the case in the prior art.

According to another feature of the invention, the first and second chambers may be positioned adjacent to and separated from one another via a separating seam. The separating seam may extend over a substantial portion of the length of the adjacent chambers where only the region of the overflow opening remains open. Adjacent chambers are easy to manufacture, in particular with the package and the de-aerating device comprising two overlapping sheet layers and the package and the chambers of the de-aerating means being manufactured with welded seams or bonded seams or the like.

According to another feature of the invention, a release agent or a separating layer or the like may be provided in the region of the overflow opening or openings and/or in the region of the outer de-aeration opening. The material of the separating layer or release agent can be selected so as to prevent the two sheet layers from welding or bonding together in the region of the separating layer. This is very advantageous since a simple manufacturing method allows to provide air passage openings at positions in the package intended therefor.

The material used for the separating layer or the release agent may contain e.g. silicone or polytetrafluoroethylene (Teflon; PTFE) or consist of another suitable material. In place of a separating layer, the separating seam may be applied in specific spots so as to leave the de-aeration openings and the overflow opening open.

A release agent allows to omit the indexing of an additional material for bonding the surfaces such that a continuous joining seam of the additional material may be employed. The release agent prevents the sheet layers from bonding with one another in the coated spots to thus generate the desired de-aeration and overflow openings. Furthermore, the additional material joined with the non-coated sheet forms a sealing lip in the region of the opening to considerably impede any entering of moisture.

According to another feature of the invention, a plurality of inner de-aeration openings may be provided which are in particular configured as de-aeration slits. The inner de-aeration openings are particularly preferably provided at one end of the first chamber which end is preferably provided near the front faces of the package.

This configuration with inner de-aeration openings in the vicinity of the end faces offers considerable advantages, in particular over the cited prior art, since in the case of a pressure exerted on a lying bag from above, de-aeration of the feed material is supported. The air trapped in the package interior and escaping from the feed material collects in particular in the corners and at the package front faces when pressure is applied from above. Inner de-aeration openings in the vicinity of the end faces thus allow good draining and conveying of the air present in the bag.

According to another feature of the invention, at least one outer de-aeration opening may be provided at one end of the second chamber and the outer de-aeration opening is in particular positioned in the vicinity of one end face of the package. Two or more outer de-aeration openings may be provided wherein one of which will be positioned in the vicinity of one end face of the package. Positioning the outer de-aeration opening or openings in the vicinity of the front or end faces of the package is also very advantageous since this allows trapped air to readily escape even from stacked packages, such that packages stacked e.g. on a pallet can de-aerate properly.

The overflow opening may be positioned between the first chamber and the second chamber in a central region of the package body. This means that the overflow opening is positioned e.g. about at the height of the flat package top face in the center of the top face.

According to another feature of the invention, with the package body filled the inner de-aeration openings and/or the outer de-aeration openings may be provided at a height distance from the flat package top face wherein it is particularly preferred that the height distance of the inner and/or outer de-aeration openings from the flat package top face is larger than the height distance from the end seam which is provided at half height of the package body. The height is measured here perpendicular to the longitudinal direction of the package and perpendicular to the end seams of the package.

The height distance of the inner de-aeration openings and/or the outer de-aeration openings from the flat package top face may be between 25 and 95% and in particular between 50 and 75% of the half-height of the package body in the filled state.

With both the inner and the outer de-aeration openings spaced from the flat package body top face and the overflow opening provided between the first and the second chamber of the de-aeration channel in the center of the flat top face, particular advantages will result since water or moisture entering must in any case overcome the height difference between the inner or the outer de-aeration opening and the overflow opening. In the bags known from DE 10 2004 026 538 A1, entering moisture must overcome the height difference only when the bag is positioned with the provided side up. When the bag is turned over such that the previously bottom side is now facing up, any water entering through the outer de-aeration opening will be conveyed through the de-aeration channel and due to gravity to the inner de-aeration opening which is in connection with the feed material. This means that the prior art bag offers increased moisture protection only in one specific position while in the other position, protection is significantly lower.

In contrast thereto, a package according to the presently disclosed specific embodiment requires any moisture entering to always overcome a height difference, independently from the storage position of the bags since the height difference is positive between the outer de-aeration opening and the overflow opening or between the overflow opening and the inner de-aeration opening.

According to another feature of the invention, the outer and the inner de-aeration openings may be positioned adjacent relative to one another.

Preferred configurations of the invention provide for the length of the de-aeration channel to be greater than the length of the package body. This is possible through the two chambers of the de-aeration channel whose total length may exceed that of the package, which is not possible with the bag known from the prior art. A longer de-aeration channel allows better protection from entering moisture.

According to another feature of the invention, both the inner and the outer de-aeration openings may be spaced apart from the flat top surface of the package body and provided in the vicinity of one end, while the overflow opening is provided between the first and the second chamber of the de-aeration channel in the vicinity of the other end and spaced apart from the flat top surface of the package body. This also results in particular advantages since water or moisture entering must in any case overcome the sum of the height differences or twice the height difference between the inner or outer de-aeration opening and the top surface of the package body.

According to another feature of the invention, the de-aeration channel may include three or more chambers interconnected in a meander pattern. This configuration allows for a particularly long de-aeration channel.

All of the embodiments of the invention provide for the separating seam between the chambers to be preferably welded or bonded.

The outer de-aeration opening in particular may be provided with a sealing lip to improve protection against water entering. The sealing lip may be manufactured for example by inserting an extrusion seam or a bonding seam or the like between the sheet layers during manufacturing of the package. The extrusion seam forms a stable connection of the two sheet layers up to the area of the de-aeration opening where a separating layer or a release agent is provided to prevent that the extrusion seam or bonding seam adheres to any one of the two sheet layers. The extrusion seam forms a sealing lip at the de-aeration opening to protect the opening from entering moisture.

All of the embodiments of the invention preferably provide depressions and/or elevations to ensure that the de-aeration channel fulfills its de-aeration function. The depressions and/or elevations are preferably embossed and may be provided in the entire de-aeration channel or only in specific portions thereof. Webs or other spacers may be provided to keep the sheet layers spaced apart.

Preferred specific embodiments of the invention provide for the package to comprise gussets and corner joints at the package corners to ensure a generally rectangular shape of the filled package.

According to another feature of the invention, at least one outer de-aeration opening may be provided at an end seam of the package.

All of the embodiments allow to provide at the de-aeration openings or at specific points in the de-aeration channel a fleece or a hygroscopic substance which when moisture enters, take up such moisture e.g. by swelling, or which cause the de-aeration channel to bond together.

The term de-aeration channel in the sense of this application is understood to mean a structure enclosed by walls which may serve to convey air.

BRIEF DESCRIPTION OF THE DRAWING

Other features and advantages of the present invention will be more readily apparent upon reading the following description of currently preferred exemplified embodiments of the invention with reference to the accompanying drawing, in which:

FIG. 1 is a schematic top view of a package according to the present invention;

FIG. 2 is a general, simplistic sectional longitudinal view of the package in FIG. 1;

FIG. 3 is a simplistic sectional side view of the package in FIG. 1;

FIG. 4 is a simplistic top view of another package according to the invention;

FIG. 5 is a third embodiment of a package according to the invention;

FIG. 6 is a general, simplistic sectional side view of a fourth embodiment of the package according to the invention; and

FIG. 7 is a cutaway, simplistic side view of the principle of a fifth embodiment of the package according to the invention.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

The depicted embodiments are to be understood as illustrative of the invention and not as limiting in any way. It should also be understood that the figures are not necessarily to scale and that the embodiments are sometimes illustrated by graphic symbols, phantom lines, diagrammatic representations and fragmentary views. In certain instances, details which are not necessary for an understanding of the present invention or which render other details difficult to perceive may have been omitted.

FIGS. 1 through 3 illustrate a first embodiment of a package 1 according to the invention configured as a bag, comprising a package body 2 provided with gussets 3 made of a plastic sheet 4.

The package 1 serves to take feed material, in particular bulk material. In filling bulk material, air will as a rule enter the package along with the product to be bagged. Furthermore, an air bubble tends to form in the top region as the bag is closed. To allow the air present in the package to escape from the closed package 1, a de-aeration means 12 is provided on the flat surface of the package 1. In the de-aeration area 13, an inner sheet layer 14 that is adjacent to the product present in the interior volume of the package 1 overlaps with an outer sheet layer 15 that is adjacent to the environment.

Between the two sheet layers 14 and 15 there is positioned a de-aeration channel 16 connecting a plurality of inner de-aeration openings 17 with one or two outer de-aeration openings 18, thus providing a flow channel for the escaping air.

The de-aeration channel 16 comprises a first chamber 19 and a second chamber 20 which in the embodiment of FIG. 1 are interconnected through an overflow opening 21 in a central region of the package surface. The air present in the package and entering the first chamber 19 of the de-aeration channel 16 through the inner de-aeration openings 17 is conveyed along the first chamber 19 of the de-aeration channel 16 up to the overflow opening 21 where it moves into the second chamber 20 of the de-aeration channel 16 where it is conveyed up to the outer de-aeration openings 18 positioned in the region of the outer edge of the second chamber 20, where it is transmitted to the exterior.

The two chambers 19 and 20 of the de-aeration channel 16 separated by a connecting seam 22, create a longer de-aeration channel than would be possible with only one de-aeration channel with only one chamber. In this way, security against moisture or water entering from outside is improved.

The inner de-aeration openings 17 are configured as short slits whose length in the present embodiment is not more than 5 mm. The overflow opening 21 is approximately 100 mm in length given a length of the bag of e.g. 40-80 cm.

The regions of the overflow opening 21 and the outer de-aeration openings 18 may each be provided with a separating layer 23 in the form of a release agent which in manufacturing the package 1 prevents the inner sheet layer 14 and the outer sheet layer 15 from welding or bonding together near the openings to ensure good function of the de-aeration channel 16.

The de-aeration region 13 may be provided with depressions and/or elevations 24 in the first chamber 19 and the second chamber 20, which are e.g. embossed to thus ensure that air is conveyed through the de-aeration channel 16. Other than shown in the illustration in FIG. 1 the depressions and/or elevations 24 serving as spacers are distributed over the entire surface of the de-aeration channel 16.

To enhance the sealing effect against water entering through the outer de-aeration openings, there may be provided in the region of the de-aeration opening 18 a bead between the inner sheet layer 14 and the outer sheet layer 15 to further improve the sealing effect against water entering.

The package 1 achieves reasonable de-aeration in storage or even with pressure applied although the de-aeration channel 16 is designed clearly longer than de-aeration channels known in the prior art. This effect is caused among other things in that the inner de-aeration openings 17 and also the outer de-aeration openings 18 are positioned in a region adjacent to the end seams 5 and 10 of the package 1.

When pressure is applied to the filled bag lying flat, the air present in the package is pushed towards the ends and the corners of the package where it can be released through the inner de-aeration openings 17 into the de-aeration channel 16. The elevations and/or depressions 24 ensure that air is conveyed through the entire de-aeration channel 16 up to the outer de-aeration openings 18 for the present air to escape.

The inner de-aeration openings 17 and the outer de-aeration openings 18 are furthermore in particular not positioned on the top package surface but in the vicinity of the end seams where the local surface is inclined horizontally or towards the top package surface. This creates a height difference 27 between the overflow opening and the layer of the outer de-aeration openings 18 or the inner de-aeration openings 17 which considerably improves the sealing effect against moisture entering from outside.

This is because in the position illustrated in FIG. 2, moisture entering from outside through the de-aeration opening 18 must firstly overcome the height difference up to the overflow opening 21 before it can penetrate further into the bag.

When the package happens to lie topside down, although any moisture entering can run downwardly due to the downward inclination between the outer de-aeration opening 18 and the overflow opening 21, for entering into the bag interior it must still overcome the height difference 27 between the overflow opening 21 now on the bottom and the de-aeration openings 17 positioned further above.

In this way, considerable safety from becoming moist is achieved in both of the two possible positions. This is positive in particular because in practice, one cannot assume e.g. that cement bags will always be stored with the same side facing up.

The arrows 25 show the path of air escaping from the inner de-aeration opening 17 through the chamber 19 and the overflow opening 21, and through the chamber 20 and the outer de-aeration openings 18 to the outside.

For achieving an optically attractive shape of the filled package and better stacking capability, the package corners 8 are welded off by way of corner joints 7. The welded off corners 8 may be provided with openings 9 which in conjunction with the corners 8 and the end seam 5 or 10 may form a carrier element 11 for the user to comfortably carry the package 1. The packages according to the other embodiments are also provided with welding corners to achieve good stacking capability wherein the welding seams have been omitted in the Figures for the sake of clarity.

The simplistic and only general illustration of the bag 1 according to the invention shown in FIG. 2 in a sectional longitudinal view shows the end seams 5 and 10 at the two ends 6 of the package 1. The outer de-aeration openings 18 having a height distance 27 of the overflow opening 21 on the top surface of the package 1 open near the ends 6 to still further increase moisture tightness. FIG. 2 does not show the inner de-aeration openings 17 also provided at the height of the outer de-aeration openings 18 to guarantee a height difference 27 independent of the bag position.

FIG. 3 shows a schematic sectional side view where the parallel chambers 19 and 20 of the de-aeration channel between the outer sheet layer 15 and the inner sheet layer 14 can be seen.

FIG. 4 shows another embodiment of a package 1 according to the invention in a simplistic top view. Unlike the embodiment in FIG. 1, the embodiment of FIG. 4 provides the inner de-aeration openings 17 and the outer de-aeration opening 18 only at one end 6 of the package 1. This allows that a particularly long de-aeration channel 16 is formed of the chambers 19 and 20 which may extend over nearly double the bag length. Where inner de-aeration openings 17 are provided at one end of the package only, these are preferably positioned in the vicinity of the head seam since after filling an air bubble will form there which can then readily drain off.

The embodiment of a package 1 according to the invention illustrated in FIG. 5 is provided with three chambers 19, 20 and 26 which combined form the de-aeration channel 16. Therein the third chamber 26 is positioned between the first chamber 19 and the second chamber 20, thus extending the de-aeration channel 16 overall. The longer the overlapping area L of the intermediate seams and the narrower the width A of the intermediate chamber 26, the better the sealing effect against entering moisture. In this embodiment the inner de-aeration openings 17 and the outer de-aeration openings 18 are also provided in end regions of the package 1 so as to ensure reasonable de-aeration even for stacked packages.

In this embodiment the separating seams 22a and 22b are not interrupted for forming overflow openings 21 but the separating seams terminate before the ends of their chambers so as to form overflow openings 21 at the ends of the chambers.

Unlike the illustration in FIG. 5, both package ends may be provided with outer de-aeration openings 18 and/or inner de-aeration openings 17.

FIG. 6 illustrates a fourth embodiment of a package according to the invention in a general and simplistic sectional side view. In this embodiment the package body 2, the outer sheet layer 15 and the inner sheet layer 14 are formed integrally. The first and second chambers 19, 20 are positioned adjacent to one another. The chambers extend one above the other at least in part and, depending on the configuration they may be not at all adjacent. A separate interlayer 28 between the outer sheet layer 15 and the inner sheet layer 14 separates the two chambers 19 and 20 from one another. The individual chambers are subdivided by means of seams 29 at the sheet.

In the fifth embodiment of a package according to the invention illustrated in FIG. 7 at least part of the first and second chambers are also positioned one above the other. The interlayer 28 is also formed integrally of the sheet such that the package body 2, the outer sheet layer 15 and the inner sheet layer 14 and the interlayer 28 consist of one piece of sheet. In manufacturing, the individual sheet layers 14, 15, and 28 are created by folding over and stacking the sheet and using suitable intermediate or bonded seams 29. The intermediate or bonded seams 29 separate and seal the chambers 19 and 20 from the side faces, except in those points where a separating layer 23 is provided (see FIG. 1).

While the invention has been illustrated and described in connection with currently preferred embodiments shown and described in detail, it is not intended to be limited to the details shown since various modifications and structural changes may be made without departing in any way from the spirit of the present invention. The embodiments were chosen and described in order to best explain the principles of the invention and practical application to thereby enable a person skilled in the art to best utilize the invention and various embodiments with various modifications as are suited to the particular use contemplated.

What is claimed as new and desired to be protected by Letters patent is set forth in the appended claims and includes equivalents of the elements recited therein:

Claims

1. A package for a filling material, comprising:

a package body made of a plastic sheet and having an interior;

a venting device having a de-aerating area bounded by an inner sheet layer and an outer sheet layer and defining a de-aeration channel in communication with the interior of the package body by an inner de-aeration opening and in communication with the surroundings of the package body by an outer de-aeration opening,

wherein the de-aeration channel has at least two separate chambers and an overflow opening for interconnecting the two chambers, with the inner de-aeration opening provided on one of the two chambers, and the outer de-aeration opening provided on the other one of the two chambers, for enhancing a water tightness.

2. The package of claim 1, wherein the two chambers are disposed in side-by-side relationship and separated from one another along a major length dimension thereof by a separating seam.

3. The package of claim 1, wherein the de-aeration device includes a separation layer in at least one region selected from the group consisting of overflow opening and outer de-aeration opening.

4. The package of claim 1, wherein the de-aeration device includes a plurality of said inner de-aeration opening on one end of the one chamber.

5. The package of claim 1, wherein the inner de-aeration opening is constructed as a perforation or slit.

6. The package of claim 1, wherein the outer de-aeration opening is disposed on one end of the other chamber.

7. The package of claim 1, wherein the overflow opening is disposed at a central region of the package body.

8. The package of claim 1, wherein the package body has a flat topside, said inner and outer de-aeration openings being disposed at a vertical distance to the flat topside, when the package body is filled.

9. The package of claim 8, wherein the inner and outer sheet layers have ends interconnected by a seam, said vertical distance of the inner and outer de-aeration openings being greater than a vertical distance of the inner and outer de-aeration openings to the end seam of the package body.

10. The package of claim 1, wherein the de-aeration channel has a length which is greater than a length of the package body.

11. The package of claim 1, wherein the de-aeration channel has at least three chambers which are connected in the form of a meander.

12. The package of claim 1, wherein the inner and outer de-aeration openings are disposed in side-by-side relationship.

13. The package of claim 2, wherein the separating seam between the chambers is a welding seam.

14. The package of claim 1, wherein the package body has opposite length sides, said outer de-aeration opening being disposed in proximity of one of the length sides, and another said de-aeration opening being disposed in proximity of the other one of the length sides.

15. The package of claim 1, further comprising a sealing lip on the outer de-aeration opening.

16. The package of claim 1, wherein the de-aeration channels has depressions and/or elevations to ensure a de-aeration function.

17. The package of claim 1, wherein the inner and outer de-aeration openings are disposed in proximity of ends of the package body, and the overflow opening is disposed in a central region of the package body.

18. The package of claim 1, wherein the package body and the inner and outer sheet layers define a single-piece construction.

19. The package of claim 1, wherein the de-aeration device includes an intermediate layer between the inner and outer sheet layers.

20. The package of claim 1, wherein the two chambers overlap one another, at least in part.

21. The package of claim 19, wherein the package body, the inner and outer sheet layers, and the intermediate layer define a single-piece construction.