Bags

Abstract

Disclosed is a bag (11), and a method of making the bag, having a welded end (12) and an open end (13) having a series of flaps or tie parts (14) formed thereon. The bag is formed from a tubular body folded upon itself along its longitudinal central region whereby no more than two gussets are formed along each longitudinal edge of the bag. A roll (10) of bags (11) is also disclosed in which the welded end (12) of one bag is joined by a line of weakness (15) to the flap or tie parts (14) of the next bag in the roll.

Description

TECHNICAL FIELD

This invention relates to bags, and more particularly, but not exclusively, plastic bags for the disposal of refuse, garbage and the like and which may be used for disposing of household waste, such as kitchen waste, as well as the carrying of fruit and vegetables and supermarket goods, and otherwise known as produce bags.

The invention particularly relates to such bags having flaps formed on their open ends, which flaps, after the bag has received its contents, can be tied together to close the opening of the bag and prevent its contents from spilling out during subsequent handling. The flaps also provide a handle formed by the tied portions of the flaps, whereby the bag can be carried, for example from the kitchen to be deposited in a refuse bin as may be provided to households by local Government Authorities, or for carrying goods to or from the checkout counter in a supermarket. Flaps also save space in the bag when tied thus saving material cost and minimising wastage.

BACKGROUND ART

One such form of plastic bag, which may or may not form part of the common general knowledge, is disclosed in Australian patent specification number 611639 and consists of front and rear panels joined to each other along three straight sides and open on the fourth side to form an open end. The open end of the panels have a series of valleys and projections formed across the bag, with the projections forming flaps or tie parts which can be tied together by hand to close the opening to the bag and as discussed above.

In the aforementioned patent specification, the bags are provided in a roll, and the ends of the panels of two of the bags in the roll are welded together and a line of weakness is formed between the two welds, whereby the two bags can be separated from each other as they are drawn from the roll. The other ends (opened ends) of the bags are joined to another adjacent bag but with a further line of weakness defining the valleys and projections which will be produced to provide the flaps for both those bags when they are separated from each other.

When the bags are progressively drawn out though an elongate opening or slit in a container for the roll of bags, the bags are individually detached from each other via the alternating lines of weakness either at their sealed ends or their open ends. When a bag is separated from the next bag in the roll at their open ends the flaps of the opened end of the roll which remain in the container protrude from the container and the flaps provide a ready means to subsequently grip that next bag and draw it from the container. However, when that subsequent bag is separated from the next bag on the roll in the container at the line of weakness between the sealed ends of the two bags, there are no flaps produced which protrude from the container and which can provide for ease of gripping to draw that next bag from the roll in the container. In this situation there is a tendency for the sealed end of that next bag to roll or move back into the interior of the container making it difficult to locate and grip the sealed end of the next bag to draw it from the container.

One other form of plastic bag, which according to our understanding does not form part of the common general knowledge, is disclosed in U.S. Pat. No. 6,183,132 (Simhaee). The plastic bag, and the roll of plastic bags, disclosed in the Simhaee reference was not previously known to us, and first became known to us when the Simhaee reference was listed in an International search report issued on our International patent application no. PCT/AU01/00788. The Simhaee reference discloses a roll of plastic refuse bags in a fully gusseted tubular form folded longitudinally to form a star seal configuration. The individual bags are separated by separation lines which form the open ends of the bags and welds which form the closed ends of the bags. A cut out region is formed in each bag along one of the longitudinal edge beneath the separation line so that when an individual bag is separated from the roll and opened, four flaps (ties) are formed which can be used to tie the bag closed. The description and claims of the Simhaee reference call for the roll of bags, and as a consequence each bag in the roll, to have one longitudinal edge which is a single longitudinal fold and that the other longitudinal edge have four gusset folds to form three gussets. The effect of three gussets formed from four gusset folds along one longitudinal edge presents difficulties in aligning the folded portions of the roll when forming the cut out regions which form the flaps or ties, whilst the resulting bag is also not consumer friendly, being hard to open, and likely to tangle when being inserted in a bin, due to the relatively large number of folds that need to be separated from each other. The bag construction, due to the number of gussets, also reduces the volume of the bag at its base. In addition the single fold along one longitudinal edge of the bag formed from only two thin layers of bag material results in a weak point at the sealed end of the bag which under the weight of refuse in the bag can fail resulting in refuse gravitating, or leaking, from the bag.

It is therefore an object of the present invention to provide a bag, and a roll of bags, which at least minimises the above problems with bags and rolls of bags of the type disclosed in the aforementioned patent specifications.

DISCLOSURE OF THE INVENTION

In accordance with the present invention, there is provided a bag having a welded end and an open end having a series of alternating valleys and projections formed thereon with said projections providing flaps or tie parts, wherein the bag is formed from the tubular body folded upon itself at least once along its longitudinal central region, and wherein no more than two gussets are formed along each longitudinal edge of the bag.

As the bag has four or more layers of bag material overlying each other and welded together the creation of a weakness at the bottom of the longitudinal side edges of the bag, when only two layers of bag material overlie each other, is avoided, whilst the creation of no more than two gussets along each longitudinal side edge of the bag minimises the problems with the three or more gussets referred to above.

The present invention also envisages, a method of forming a bag having a welded end and an open end having a series of alternating valleys and projections formed thereon with said projections providing flaps or tie parts, wherein a tubular body is folded upon itself at least once along its longitudinal central region and whereby no more than two gussets are formed along each longitudinal edge of the bag.

The present invention also envisages a roll of bags, said bags being accordance with that defined above, and wherein the welded end of one bag is joined by a line of weakness to the tops of the projections of the next bag in the roll.

The roll is orientated in its container so that the projections of each successive bag is the end that always extends and projects from the container for the roll, and thus provide for ease of gripping and without the tendency for the end of the next bag to move back into the container when the leading bag is separated therefrom at the line of weakness between the bags. A further advantage of the invention, when in the form of a roll of bags, is that bags are only joined together at the tops of the projections and thus the remainder of those ends of the bags are already open and separation at a line of weakness across the entire end, of what will be the open end of the bag, is not necessary as in the case with the roll of bags disclosed in Australian patent specification no. 611639.

BRIEF DESCRIPTION OF THE DRAWINGS

Three preferred embodiments of the invention will now be described with reference to the accompanying drawings, in which;

FIG. 1 is a perspective view of a roll of bags in accordance with the preferred embodiment of the invention,

FIG. 2 is a side view of the roll of bags of FIG. 1, and

FIGS. 3, 4, 5, 6, 7, 8, 9 and 10 are schematic transverse cross-sectional views through a tube of bag material and showing four alternative ways that the tube may be folded to form a bag or roll of bags in accordance with the present invention.

BEST MODES FOR CARRYING OUT THE INVENTION

Referring to FIGS. 1 and 2 of the drawings, there is provided a roll of bags 10, each bag 11 having a welded end 12 and an open end 13 having a series of alternating valleys and projections formed thereon with said projections providing flaps or tie parts 14. The welded end of one bag is joined by a line of weakness 15 to the tops of the projections or flaps 14 of the next bag in the roll.

The roll is orientated in its container (not shown) so that the projections or flaps 14 of each successive bag is the end that always extends and projects from the container for the roll, and thus provide for ease of gripping and without the tendency for the end of the next bag to move back into the container when the leading bag is separated therefrom at the line of weakness 15 between the bags. A further advantage of the invention is that bags are only joined together at the tops of the projections or flaps 14 and thus the remainder of those ends of the bags are already open and separation at a line of weakness across the entire end, of what will be the open end of the bag, is not necessary as in the case with the roll of bags disclosed in the aforementioned patent specification.

With reference to FIG. 3 of the drawings, the bags, and roll of bags, in accordance with the four preferred embodiments of the invention are formed from a flattened tube 20 of plastics material and of the type used for conventional bags.

In a first embodiment the tube 20 is subsequently folded in accordance with the folding sequence shown in FIGS. 4 and 5, that is, the outer side edge portions 20a are firstly folded inwardly across the remainder of the tube but on opposite sides thereof as shown in FIG. 4, whereafter the tube is folded upon itself along its longitudinal centre line as shown by the arrow in FIG. 4 to produce the folded bag or roll as shown in FIG. 5. The necessary cutouts 13 and welds 12 are then formed, whilst, in the case of a roll of bags, the lines of weakness 15 are also formed.

In a second embodiment, the tube 20 is folded in accordance with the folding sequence shown in FIGS. 6 and 7, that is, the outer side edge portions 20a are firstly folded inwardly across the remainder of the tube but on the same side thereof as shown in FIG. 6, whereafter the tube is folded upon itself along its longitudinal centre line as shown by arrow A in FIG. 6 to produce the folded bag or roll as shown in FIG. 7. In an alternative third embodiment the folded tube 20 as shown in FIG. 6 may be folded in the opposite direction as shown by arrow B in FIG. 6 to produce the folded bag or roll as shown in FIG. 8. Once again the necessary cutouts 13 and welds 12 are then formed, whilst, in the case of a roll of bags, the lines of weakness 15 are also formed.

As can be seen in FIG. 9, the bag is folded upon itself along its longitudinal mid-region so that opposite edges 20b of the bag are placed adjacently on one side while a first fold line 20c is formed on the opposite side.

The tube is subsequently folded again along its mid-region so that the first fold 20c line is placed adjacent to the edges 20b of the bag and thereby forming a second fold line 20d.

Once again the necessary cutouts 13 and welds 12 are then formed, whilst, in the case of a roll of bags, the lines of weakness 15 are also formed.

Claims

1. A bag having a welded end and an open end having a series of alternating valleys and projections formed thereon with said projections providing flaps or tie parts, wherein the bag is formed from the tubular body folded upon itself at least once along its longitudinal central region, and wherein no more than two gussets are formed along each longitudinal edge of the bag.

2. A bag as claimed in claim 1, wherein the tubular body is folded upon itself whereby at least one fold overlies another portion of the bag along each longitudinal edge thereof.

3. A method of forming a bag having a welded end and an open end having a series of alternating valleys and projections formed thereon with said projections providing flaps or tie parts, wherein a tubular body is folded upon itself at least once along its longitudinal central region and whereby no more than two gussets are formed along each longitudinal edge of the bag.

4. A method of forming a bag as claimed in claim 3, wherein outer side edge portions of the tubular body are firstly folded inwardly across adjacent portions of the remainder of the tubular body and to the centre line of the tubular body but on opposite sides thereof, whereafter the tubular body is folded upon itself along its longitudinal centre line.

5. A method of forming a bag as claimed in claim 3, wherein outer side edge portions of the tubular body are firstly folded inwardly across adjacent portions of the remainder of the tubular body to the centre line of the tubular body and on the same side thereof, whereafter the tubular body is folded upon itself along its longitudinal centre line.

6. A method of forming a bag as claimed in claim 5, wherein the tubular body is folded upon itself along its longitudinal centre line on the side opposite to the folded side edge portions.

7. A method of forming a bag as claimed in claim 5, wherein the tubular body is folded upon itself along its longitudinal centre line on the same opposite as the folded side edge portions.

8. A method of forming a bag as claimed in claim 3, wherein the tubular body is folded upon itself along its longitudinal centre line, whereafter the tubular body is once again folded upon itself along the longitudinal centre line of the previously folded tubular bag.

9. A method of forming a bag as claimed in claim 3, whereinafter folding of the tubular body the welded end of the bag, and the valleys and projections of the open end of the bag, are formed.

10. A bag produced in accordance with the method of claim 3.

11. A roll of bags of the type defined in claim 1, wherein the welded end of one bag is joined by a line of weakness to the projections of the open end of the next bag in the roll.

12-14. (canceled)