CA1125078A - Container having indented lining top - Google Patents

Abstract

ABSTRACT OF THE DISCLOSURE
The present invention provides a container comprising an outer container of cardboard or similar material and a lining of plastic or any other easily formable material which is dispos-ed in the outer container and which at one end of the container exposes a preferably even, openable lining end, and which lining is fed from and closed at the opposite end thereof, characterized in that the lining at the end thereof to be opened is slightly pressed down into itself thereby providing a projecting rib of two layers of lining material extending round its upwards directed opening end, and in that the outer container has top flaps extend-ing from the upper edge thereof which flaps are folded in and attached to the projecting rib of lining material so that the lining at the opening end is thereby secured in the outer contain-er with the opening end extending somewhat from the upper edge of the outer container.

Description

5~3~7~

The present inventian relates to a container comprising an outer container of cardboard or similar stiff material and a lining of plastic or other easily formable and preferably ~as-sealing material which lining is disposed in the said outer container and which at the end of the container to be opened exposes an even single layer of lining material, and which is filled from and closed at the opposite end thereof.
The container according to the invention can be used for packing of any types of goods, but it is in particular suit-ed for the packing of compressed and/or evacuated goods of the type which is to be packed hermetically sealed. It is however to be understood that the contalner can as well be used for packing of any other solid or liquid product.
Containers are known, which at the end thereof to be opened expose an even surface of lining material without joints, welds and other means which can make the opening of the container lining difficult. The opening generally takes place in that the lining is cut open by a knife or it is opened by a special tear tongue or similar means.
The known containers are formed so that the lining with the end thereof to be opened e~tend substantially in the plane of the upper edge of the outer container. The containers are filled from the bottom and are sealed at the bottom, and since the packed goods can usually not be made to completely fill the volume of the outer container some empty space is obtained at the bottom of the container. If the containers are handled carelessly or if they are subjected to shaking or vibrating during transport or similar procedures the lining may become unstuck from the outer container which may give the container a less attractive appearance and it may make the opening of the contain-er difficult.

.'', ~

When the container is opened by cutting or tearing open the opening end of the lining a portion of the packed goods may penetrate from the lining and tend to drop out of the container.
Also the packed goods may tend to penetrate into the space be-tween the lining and the outer con-tainer, which in turn further increases the risk that the lining becomes unstuck from the outer container. Especially when such types of containers are used as distribution containers for instance for coffee, flour and grain there is a great risk of spilling some product when picking a portion of the packed goods up since the packed goods are located as high in the container as substantially at the level of the upper edge of the outer container.
The present invention therefore provides a method and apparatus for making a container of the above-mentioned type which at the opening end exposes an even single layer of lining material and in which the lining is secured to the outer contain-er especiall~ adjacent the upper edge of the container, and in which the lining and the outer container are formed and connected so that the opening end of the container is somewhat lowered ~rom the upper edge of the outer container.
According to the present invention there is provided a method of manufacturing a container comprising an outer con-tainer of cardboard or similar stiff material and a lining of plastic or any other easily formable material, which is disposed in the said outer container and which at one end of the container exposes an openable lining end, and which is intended to be filled and closed at the opposite end, whereby a tubular outer container blank is provided having bottom closure flaps the combined surface of which is at least as large as the bottom surface of the container and top flaps the total surface of which is substanitally less than the cross sectional area of the ~5~7~

con-tainer, and separately a lining blank is provided in the shape of an open lining ~a~, characterized in that the lining bag is introduced into the outer container blank so that the opening upper end thereof is positioned at or adjacent the upper edge of the outer container, whereupon the lining from the open-ing end is pressed back to provide a lining rib extending round the opening end, whereupon the lining is secured in the outer container in that the top flaps of the outer container are folded in and are secured to the said lining rib.
Further characteristics of the invention will be evident from the following detailed specification in which reference will be made to the accompanying drawings.
In the drawings Figure 1 is a perspective view of a partly made container before being filled and sealed.
Figure 2 is a cross section alony line II-II of the container according to Figure 1. : -Figure 3 is a perspective view showiny the appearance of the lining separately before said lining is secured in the outer container.
Figure 4 shows diagrammatically and in a vertical cross section the method for forming the lining rib extending round the opening end of the lining, and Figure 5 is a sequence of pictures which diagrammati-cally illustrate -the method cf manufacturing the container accoxd-ing to the invention.
Figure 6 diagrammatically illustrates a step in the manufacture of the container according to the invention.
Figure 7 shows, partly in anaxial cross section, an apparatus for executing the method seen along line VII-VII of Flgure 8 and, Figure 8 is a cross section along line VIII-VIII of ~5r3~7~

Figure 7.
Figure 9 diagrammatically illustrates in five different views a-e the method for manufacture of a container according to the invention.
The container shown in Figures 1-3 generally comprises an outer container 1 of cardboard or similar stiff material and a lining 2 of an evenly foldable and preferably liquid and gas sealing material such as plastic or a plastic-aluminium laminate which lining is disposed in the outer container 1.
10The outer container 1 may have any cross sectional shape including square, rectangular, circular and elliptical.
The outer container is made from a flat punched blank comprising sides 3, bottom closure flaps 4 and top closure flaps 5. Before the lining 2 is introduced in the outer container said outer ~`
container is folded together to tubular form, the joint 6 being preferably located adjacent a corner. The bottom closure flaps 4 are large enough to provide for closing of the bottom of the outer container by overlapping of at least two opposite flaps.
The top flaps S are relatively narrow and the width thereof is defined by the desired depth of the opening end 8 of the lining under the upper edge 7 of the container. When the upper end of the container is ready the top flaps 5 are folded in and enclose between themselves and the outer container sides 3 at least a part of the lining 2.
The lining is made of a flat-strip of lining material which is folded double whereupon the two side edges are welded together to provide two side joints 9, whereby the lining has the appearance of a flat sack. The lining is conformed to the desired shape preferably by means of a mandrel the shape of which corresponds to the shape of the outer container and which is slightly smaller than the inner surface of the outer container.

,~, When folding the lining up to the four edge form which is shown in Figures 1-3 two opposite lining ears 10 are formed at two opposite upper edges which ears are folded down along the sides 11 of the lining. After the lining is folded up to its desired form it is pushed into the outer container and it is formed in a way, which will be hereafter described in more detail so that the opening end 8 of the lining is pushed back a small distance into the lining to provide a lining rib 12 extending around the opening end 8 which rib except for the lining ears comprises two layers of lining material. The two layers may be fixed in rela-tion to each other by point welds or rib welds 13 which connect the two layers of lining material. The upper edge 14 of the lining rib 12 may be provided adjacent the upper edge 7 of the outer container, but preferably the edge 14 is located at a slightly lower level than the edge 7 of the outer container in order to make the double folded outer container edge as smooth and thin as possible and to facilitate the attachment of the top flaps 5 by a cardboard to cardboard connection at the space 15 between the upper edges 7 and 14 of the outer container and the lining respectively.
The container lining 2 is filled and closed at the bottom in a conventional way, and the bottom closure flaps 4 of the outer container provides theccm~osite bottom of the container.
The method of manufacturing the container according to the invention includes the following series of manufacturing steps:
1. An outer container blank is manufactured by being punched, creased and folded together to tubular form from a plane blank of cardboard or similar stiff material, and concurr-ently herewith a lining blank is manufactured by folding a flatlining material blank 2 together and folding the side edges of 7~ -said double folded blank together at 9 to provide a flat lining bag.

2. The lining bag 2 is opened 'in any suitable way such as by means of suction devices 1~ to enable the introduction of a forming tool into the remaining open end of the lining.

3. For forming the lining a mandrel can be used, for instance an expandable mandrel 17 which in its non-expand'ed state can easily be introduced into the lining bag and which on being expanded gives the lining bag its des.ired shape, whereby the projecting lining ears 10 are formed.

4. During the expansion of the mandrel 17 the lining .'is successively int'roduced into the ope'ned outer container tube 1, whereby the lining ears 10 are folded back towards the sides~ll of the lining~ The lining is introduced into.the outer'container with the upper end of the lin.ing adjacent the uppe.r edge 7 of the outer container; but the up~er end of the -lining may optionally he located above or underneath the said upper edge 7.

5. When the linlng is located in the desired position in the outer container blank the mandrel 17 is contracted and is pulled out of tbe lining.

6~ Now a fixed mandrel 18 is introduced in the lining which mandrel is best shown in Figure 4. The said fixed mandrel 18 has at the upper end thereof a projecting narrow rib 19 over which the lining rib 12 is to be formed. Depending on the desired hei.ght of the lining rib 12 the mandrel 18 is introduced to a level at or preferably some distance under the upper side 20 of the lining. For co~operation with the edge rib 19 of the mandrel 18 there is a piston 21 the outer dimensions of which substantially correspond to or are slightly less than the inner , surface of the rib 19.

7. The outer container blank 1 with the lining 2 and the mandrel 18, 19 is provided in a cartridge so that the said ~ 6 -,~, ~2~

th~ee parts are kep~ in ~he desired position in relation to each other.

8. ~f desired the lining may be pre-secured in the outer container by means of glue points so that the lining is not moved in the outer container during subse~uent operations.

9. For forming the lining rib 12 the piston 21 is pressed down into the area inside the rib 19 of the mandrel 18, whereby part of the upper side 20 of the lining is pressed down at the same time, which part is the opening end 8 of the lining.
As mentioned previously the height of the lining rib 12 and the distance thereof from the upper edge 7 of the outer container may be adapted to circumstances, and if a high rib is desired the edge rib 19 of the mandrel 18 is made correspondingly high and the mandrel is placed at a corresponding great distance under the upper side 20 of the lining blank. If a narrow lining rib is desired the rib 1~ of the mandrel 18 need not be higher than the desired lining rib. If it is desired to locate the upper edge 14 of the lining rib in line with the upper edge 7 of the outer container the lining blank is introduced in the above described step ~ so that the upper side 20 thereof is located above the upper edge 7 of the outer container by a distance cor-responding to the movement downwards and the edge formation which is provided by pressing the piston 21 down.

10. Except for the lining ears 10 and lining rib 12 is composed by two layers of lining material, and to prevent a relative movement between the said two layers of lining material during the subsequent treatment the layers are connected by being welded together at 13 by points, rib portions or a weld rib extending around the entire lining rib. At least two opposite edges of the lining rib 12 are connected as mentioned and the said two edges preferably are the edges which have no lining ears.

_ 7 _ ~5~

11~ The projecting top flaps 5 of the outer container are now supplied with glue 22 such as hot-melt glue. In the application of glue the top flaps may be folded fully outwards to the outsides of the outer container and the outer container blank dipped into a glue bath whereby glue sticks both to the top flaps 5 and to the space 15 between the upper edge 14 of the lining and the upper edge 7 of the outer container and it may also to some degree stick to the inner surface of the lining rib 12.

12. Now the top flaps 5 are folded in to enclose the lining rib 12 between the said top flaps 5 and the sides 3 of the outer container. It is to be understood that the height of the top flap should correspond substantially to the distance between the opening end 8 of the lining and the upper edge 7 of the outer container so that the top -flaps 5 are positioned in contact or close to the opening end 8 of the lining.

13. After the upper end of the container is completed as described above the container is turned upside down and is filled and closed from the bottom which is still open. The fill-ing, the closing and the sealing is effected in a conventionalway. The filling step may also include compressing of the goods to be packed, evacuation of the air contents etc.
Since the opening end 8 of the lining is located some distance under the upper edge 7 of the outer container the top flaps 5 act as a non-spill edge for packed goods which may come from the container at the same time as they-saEèly attach the lining to the outer container adjacent the upper edge -thereof.
The container is easily opened when the opening end 8 of the lining is cut open or the said end of the lining is formed witll a strip off indication or similar means. With the above container there is no risk that the packed goods penetrates into the space . .

~; ~ .

'; . ' $7~

between the lining and the outer container thereby tending to release the lining from the outer container. Also the risk of the lining being released from the outer container due to jarring, vibration or careless handling is substantially completely eli-minated even if there should be any space between the lining and the~bottom of the outer container after the lining is filled and closed.
In a modified method of manufacturing a container according to the invention illustrated in connection to Figure 9 of the drawings an outer container sleeve 1 and a lining bag 2 are manufactured independently of each other, whereupon a fixed mandrel 18 which to form and size substantially corresponds to the desired shape of the lining is introduced in the lining and under the action of the said mandrel the lining is introduced as far in the outer container sleeve that the even énd surface of the lining is located a short distance under the upper edge 7 of the outer container. The lining ears 10 are folded down along the sides of the lining when the lining bag is introduced into the outer container sleeve. An exhauster 23 holds the lining and the fixed mandrel 18 is pulled out and is substituted by an expandable mandrel 24 having a spring actuated bottom plate 25, which is introduced into the lining bag. The mandrel 24 is expanded such that the corners thereof are moved outwards until the lining is given the correct shape, the exhauster 23 is removed, and co-operating with the spring actuated bottom plate 25 at the inside of the lining on external piston 21 forces the lining from the outside down into itself. During said operation the lining keeps its position in the outer container sleeve. The expandable mandrel 24 is retracted some distance in the lining at the same time as it regains its contracted position. This is illustrated in Figure 9b.

g _ ~51[~i7~3 In Figure 9c is illustrated how the two layers of -lining material are welded to~ether at the lining rib 12 which is made by means of weld jaws 26 which from inside are moved out to the lining rib thereby welding the two layers of lining material together at points or at rib portions or completely co operating with counter jaws 27 acting from outside.
In Figure 9d is illustrated how the top flaps 5 of the outer container are folded out and the outer container with the lining is moved down through a glue mold 28 and down into a glue bath 29 while the top flaps 5 by the glue mold 28 are folded up along the sides of the outer container. When moving the outer container down into the glue bath 29 a strip of glue 22 is obtain-ed at and adjacent the upper edge oE the outer container as ill-ustrated in Figure 6.
After glue is appIied the outer container with the lining is pulled up on the glue mold 2~ and the top flaps 5 are folded in and are compressed thereby enclosing the lining rib 12 which is made by means of an inner mandrel 30 and an outer counter tool 31.
For pressing down the lining top to provide the lining rib 12 an apparatus is used which includes an expandable mandrel of the type which is illustrated in Figures 7 and 8. The expand-able mandrel comprises a supporting shaft 32 which is movable in the vertical direction and on which a mandrel arm holder 33 is axially movable a limited distance. The mandrel arm holder 33 rotatably supports four mandrel arms 35 about pins 34, each mandrel arm providing a right-angled corner. The mandrel arms 35 are rotatably radially outwards from the center of the shaft 32, and at the lower end they have a thin corner rib 36 over which the lining rib is to be formed. On the shaft 32 a cam means 37 is fixedly mounted, and for co-operation with the said 37~

cam each mandrel arm has a guide roller 38. ~etween the cam means 37 and the mandrel arm 33 a compression spring 39 is mounted. The cam means 37 is widened in the downwards direction so that the mandrel arms 35 are expanded when the mandrel arm holder 33 is moved downwards in relation to the supporting shaft 32. The compression spring 39 tends to keep the mandrel arms in their raised and non-expanded position. Contraction springs 40 contribute to a retraction of the mandrel arms to the said non-expanded position. A pressure plate ~1 is mounted to be axially movable at the bottom of the supporting shaft 32 and the said pressure plate 41 is pressed downwards by a spring 42. For the sake of clarity Figure 7 shows the pressure plate 41 raised some distance from the bottom (top) of the lining but it is to be understood that the pressure plate ~1 contacts the bottom of the lining bag when the mandrel arms 35 are fully moved down in the lining bag. In order to keep the lining bag in an open position a holder arm 43 is mounted at each corner or each side of the lining bag. The said holder arms 43 can be stationary mounted and spring biassed so that they are rotated down to their posi-tions shown in ~igure 7 when the expandable mandrel is introducedin the bag.
As mentioned previously there is a piston 21 which co-operates with the apparatus for forming the lining, which piston is axially movable and which against the action of the spring loaded pressure plate 41 can press back the even opening end of the lining to give a lining rib 12 extending round the end of the lining which is intended to be opened.
The apparatus operates as follows: When moving the lining forming means down into the lining bag 2 the mandrel arms 35 are in their upper non-expanded position, but when the appara-tus has been moved down to the desired position in the lining bag 58i7~3 the mandrel arm holder 33 is moved downwards in relation to the supporting shaft 32 whereby the mandrel arms 35 b~ co-operation of the cam means 37 and the guide rollers 38 are moved outwards while the lining is pressed outwards at its corners. The spring loaded press plate 41 thereby contacts the bottom of the lining.
Thereafter the piston 21 is moved upwards so that the end 8 of the lining to be opened is pressed back into the lining thereby providing a lining rib 12 extending round the lining end. With co-operation being maintained between the ~iston 21 and;the spring loaded press plate 41 and mandrel arms 35 are pulled up some distance so that the corner ribs 36 thereof are pulled out of the two layer lining lists thereby provided and so that the mandrel arms 35 regain their non-expanded position, whereupon the expandable mandrel including the spring loaded press plate 41 is pulled out of the lining bag. Thereafter the two layers oE
the lining material at the lining rib ]2 are welded together as mentioned above and the container is filled, sealed and closed likewise as mentioned above.

Claims (20)

THE EMBODIMENTS OF THE INVENTION IN WHICH AN EXCLUSIVE
PROPERTY OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:

1. A method of manufacturing a container comprising an outer container of stiff material and a lining of easily formable material disposed in said outer container, said lining exposing at one end of the outer container an openable lining end, said lining being adapted to be filled from and closed at an opposite end thereof, which method comprises providing a tubular outer container blank having bottom closure flaps, the combined surface of which is at least as large as the bottom surface of the container and top flaps, the total surface of which is sub-stantially less than the cross sectional area of the container, and separately providing a lining blank in the form of an open lining bag, introducing the lining bag into the outer container blank so that the upper. opening end thereof is positioned at or adjacent an upper edge of the outer container, whereupon the lining of the opening end is pressed back to provide a lining rib extending round the opening end, and the lining is secured in the outer container by folding the top flaps of the outer container in and secured to the said lining rib.

2. A method according to Claim 1, in which the lining blank is opened to a desired shape by means of an expandable mandrel, triangular lining ears thus being formed Which are folded back along sides of the lining blank as the lining is introduced in the outer container blank, and after the lining is introduced in the outer container blank the expandable mandrel is removed from the lining blank and the outer container blank with the lining blank is mounted in a cartridge for holding the container during continued handling thereof.

3. A method according to Claim 1, in which the lining rib is formed by introducing a mandrel into the shaped lining blank, which mandrel has a projecting rib extending round the upper end thereof, and the lining rib is formed on the said mandrel rib by pressing the lining down into the space inside the mandrel rib from outside.

4. A method according to Claim 3, in which the pressing down of the lining into the space inside the mandrel rib is effected by a reciprocating piston, the outer dimensions of which are slightly smaller than the inner dimensions of the mandrel rib.

5. A method according to Claim 1, in which the lining rib is secured in the outer container between the top flaps and sides of said outer container.

6. A method according to Claim 5, in which the lining rib is secured in the outer container by means of a glue joint.

7. A method according to Claim 1, in which the lining blank is introduced into the outer container blank and the opening end of the lining blank is pressed down to an extent into the lining blank that the upper edge of the lining rib is located below the upper edge of the outer container blank.

8. A method according to Claim 1, in which the lining blank is introduced in the outer container blank to an extent such that the upper end thereof is positioned above the upper edge of the outer container blank, whereupon tile opening end of the lining is pressed down into the lining blank to such an extent that the upper edge of the lining rib is located at or under the upper edge of the outer container blank.

9. A method according to Claim 3, in which the mandrel forming the lining rib is introduced in the lining blank to a level under the upper side of the lining blank, such that the lining is stretched about the mandrel rib to provide the lining rib when the opening side of the lining is pressed down into the space inside the mandrel rib.

into the space inside the mandrel rib.

10. A method according to Claim 1, 2 or 3, in which the lining is secured in the outer container blank at one or more points before the opening end of the lining is pressed back.

11. A method according to Claim 1, 2 or 3, in which the two layers of lining material forming the lining rib are welded together before the top flaps of the outer container are folded down and are secured to the lining rib.

12. A method according to Claim 1, in which the lining bag is introduced in the outer container blank by means of a fixed mandrel, and the lining bag is maintained in position in the outer container blank, whereupon the fixed mandrel is withdrawn and an expandable mandrel is introduced in the lining bag and the expandable mandrel is expanded after it is completely introduced in the lining bag, and after the opening end of the lining is pressed back the expandable mandrel is pulled up some distance of the lining bag while being retracted to its non-expanded position, whereupon the mandrel is completely withdrawn from the lining bag.

13. A method according to Claim 12, in which the opening end of the lining bag is kept stretched between an inner spring actuated press plate and a piston acting from outside during the first stage of the withdrawal and de-expansion of the expandable mandrel after the lining rib is formed.

14. A method according to Claim 12 or 13, in which the lining bag is maintained in an expanded position by means of a plurality of holder arms engaging the upper edge of the lining bag during the action of the expandable mandrel in the lining bag.

15. A method according to Claim 12 or 13, in which the top flaps of the outer container are folded out along the sides of the outer container blank after the opening end of the lining bag is pressed back and while the outer container blank is moved through a glue mold and down into a glue bath so that a strip of glue is applied along and on both sides of the upper edge of the outer container blank, whereupon the top flaps are folded in thereby enclosing the lining rib between the top flaps and sides of the outer container blank.

16. A method as claimed in Claim 1, 2 or 3, in which the outer container is made of cardboard and the lining of a plastics material.

17. An apparatus for manufacturing a container com-prising an outer container of a stiff material and a lining of easily formable material which is disposed in the outer container and which at one end of the container exposes an openable lining end and which is adapted to be filled and closed at the opposite end, and in which the lining bag at the opening end thereof is slightly pressed in to provide a pro-jecting lining rib extending round the openable lining end and in which the lining rib is enclosed between top flaps and sides of the outer container, said apparatus comprising an expandable mandrel including a plurality of rotatably mounted mandrel arms which at the lower ends thereof have a thin corner rib, which mandrel arms are rotatable in direction out towards corners of the container, whereby an expansion of the mandrel arms provides for pressing outwards of the corners of the lining bag.

18. An apparatus according to Claim 17, in which the mandrel arms are mounted for axial movement on a supporting shaft and the mandrel arms co-operate with a cam means which is fixedly mounted on the supporting shaft so that the mandrel arms are expanded when being moved downwards in relation to the supporting shaft.

19, An apparatus according to Claim 18, in which the supporting shaft at the lower end thereof carries a press plate which is spring biased downwards and which co-operates with a piston acting from outside the lining for pressing the opening end of the lining inwards, and which is withdrawn from the opening end of the lining after the mandrel arms have been moved up from the lining blank.

20. An apparatus according to Claim 17 or 18, in which the mandrel arms are mounted in a mandrel arm holder which is axially movable on the supporting shaft, and a pressure spring provided between the fixed cam means and the mandrel arm holder is adapted to move the mandrel arm holder away from the cam means, whereby the mandrel arms take their non-expanded positions.