US3033439A

US3033439A - Packaging

Info

Publication number: US3033439A
Application number: US81305A
Authority: US
Inventors: Arenbeck Helmut
Original assignee: NATRONZELLSTOFF und PAPIERFAB
Current assignee: NATRONZELLSTOFF und PAPIERFAB; NATRONZELLSTOFF- und PAPIERFABRIKEN AG
Priority date: 1960-01-07
Filing date: 1961-01-09
Publication date: 1962-05-08
Anticipated expiration: 1979-05-08
Also published as: CH389386A; GB930581A; LU39543A1; NL259266A; BE598881A

Description

H. ARENBECK May 8, 1962 PACKAGING 5 Sheets-$heet 1 Filed Jan. 9, 1961 liilllll v'l'llliifllllll.

May 8, 1962 Filed Jan. 9, 1961 H. ARENBECK 3,033,439

PACKAGING 5 Sheets-Sheet 2 May 8, 1962 Filed Jan. 9, 1961 H. ARENBECK PACKAGING 5 Sheets-Sheet 3 3,033,439 PACKAGING Helmnt Arenbeck, Goslar, Germany, assignor to Natronzellstolfund Papierfabriiren A.G., Mannheim, Germany Filed Jan. 9, 1961, Ser. No. 81,305 Claims priority, application Germany Jan. 7, 1960 11 Claims. (Cl. 229-625) The present invention relates to the art of packaging.

Certain types of materials such as colfee, sugar, and the like are packaged in containers of flexible material such as paper or the like, and a particular problem resides in closing such containers after they are filled. Various typ s of valve arrangements are used for the purpose of closing these containers after they are filled, but all of the known solutions to the problem are exceedingly complex and not very reliable, and in addition they are quite expensive.

It is accordingly one of the primary objects of the present invention to overcome the above drawbacks and to provide containers of the above type with inlet opening structures which are capable of being quickly and easily closed in a simple and inexpensive manner.

Another object of the present invention is to provide for containers of the above type tubular inlets which can be closed very quickly simply by application of heat to the tubular inlet.

It is also an object of the present invention to provide containers which have tubular inlets which can be closed in an extremely short time without requiring any special structure for the tubular inlet beyond what is more or less conventional in the art.

It is furthermore an object of the present invention to provide a container construction which will enable the tubular inlets to close while the containers are moving along a conveyor after the containers are filled.

With the above objects in view the invention includes a package which comprises a container and a tubular inlet fixed thereto, the container being entirely closed except for the tubular inlet which provides communication between the exterior and interior of the container, and the tubular inlet is made up at least in part of a heat-shrinkable material so that after the container is filled through the tubular inlet thereof heat may be applied to the heatshrinkable material to shrink this material and thus close the tubular inlet so as to completely close the container after it is filled.

Also in accordance with the present invention the process is provided according to which the container is first filled and then heat is applied to the tubular inlet so that the heat-shrinkable material thereof will shrink and close the tubular inlet so as to completely close the container.

The novel features which are considered as characteristic for the invention are set forth in particular in the appended claims. The invention itself, however, both as to its construction and its method of operation, together with additional objects and advantages thereof, will be best understood from the following description of specific embodiments when read in connection with the accompanying drawings, in which:

(FIG. 1 is a fragmentary partly sectional partly diagrammatic illustration of a container according to the invention during the filling thereof, FIG. 1 showing one pos sible embodiment of a structure for heating the heatshrinkable material of the tubular inlet;

FIG. 2 shows the container of FIG. 1 provided with the tubular inlet of the invention, this tubular inlet being shown on a somewhat smaller scale in FIG. 2;

ice

FIG. 3 shows the structure of FIG. 2 after the container has been completely closed;

FIG. 4 shows a container during the filling thereof according to a different embodiment;

FIG. 5 illustrates the container of FIG. 4 as it is being moved away from the filling apparatus;

FIG. 6 shows the container of FIGS. 4 and 5 after it is completely closed;

FIG. 7 is a fragmentary illustration of another embodiment of a container according to the present invention;

FIG. 8 is a transverse section illustrating the tubular inlet of the embodiment of FIG. 7;

FIG. 9 is an illustration of the closing of the container;

FIG. 10 is a view transversely through a conveyor showing diagrammatically how a package is conveyed past a source of hot air for sealing the package; and

FiG. 11 is a longitudinal illustration of the conveyor of FIG. 10, showing the package openings which receive the blast of hot air.

Referring now to FIGS. 1-3, the container 1 of the package illustrated diagrammatically therein is in the form of a bag, sack, or the like made of paper, plastic foil, a woven fabric, or the like. For example, jute or another suitable material may be used for the container 1. The container is entirely closed except for the tubular inlet 4. For example, the ends of the container may be folded and the various folded layers may be glued to each other in a well known manner so that the container is completely closed except for the tubular inlet, or in the case of a fabric the container may be sewed so as to be closed except for the tubular inlet. The tubular inlet is located at the upper left corner of the container, as indicated in FIGS. 1-3 where the container is provided with the portion 2 spaced below the upper wall portion 3 so. as to provide the passage for the tubular inlet 4. The tubular inlet 4 is completely housed within the container, as indicated in FIGS. 1-3, and it is made of a plastic material, in accordance with the present invention, as described below. The plastic wall of the tubular inlet 4 may be permanently joined with the paper, fabric, or the like of the container 1 as by being fused thereto in any suitable way, as by being glued thereto, or by any other suitable well known expedient. Instead of a tubular inlet 4 which is made up entirely of plastic, it is possible to provide a paper tubular member which is lined along its inner surface with a plastic tube, and of course such a paper tube may be glued to the paper container and the plastic liner is fused to the paper tube at the inner surface thereof in any well known manner.

In accordance with the present invention the plastic material of the tubular inlet 4 is such that it will shrink when heat is applied thereto.

Plastic materials which are heat-shrinkable are well known, and the invention does not reside in the choice of any one specific heat-shrinkable material but rather in the use of a tube made of such a material in the package combination disclosed. Thus, the plastic material of the tubular inlet of the invention may be, for example, a terephthalic acid ester foil or a stretched low-pressure polyethylene foil, or a stretched polypropylene foil, or the like. Such plastic materials when they have heat applied thereto will shrink quite rapidly and to such large extent that the tubular inlet made of such material will become closed. The temperature to which the plastic material is heated to produce the desired shrinking is between 50 and C.

The sudden heating of the tubular plastic inlet of the invention so as to shrink the same can be provided in any number of suitable ways. Thus, as may be seen from FIG. 1, a tubular outlet 5 of the filling machine which contains the material which is filled into the container 1 is inserted through the tubular inlet 4, and the tubular outlet 5 terminates in a downwardly directed opening 6 through which the material such as coffee, sugar, or the like drops into the container 1. It will be noted that the tubular outlet 5 of the filling machine tapers toward the end which is provided with the opening 6. At suitable places such as those indicated at 7 and 8 in FIG. 1 the tubular outlet 5 of the filling machine is provided with suitable electrodes which are connected in any suitable unillustrated manner with a source of electrical current or the like. These electrodes may take the form of electrical resistors which will become rapidly heated when current is supplied thereto, or they may be in the form of high frequency electrodes which will also produce considerable heat when supplied with current. At the exterior the

electrodes

7 and 8 are covered with a material which is not electrically conductive, such as, for example, polytetrafluoroethylene. However, it is alsov possible to provide heating by way of a heated stream of gas as air, for example.

After the container is filled, and just prior to slipping of the tubular inlet 4 off the filling tube 5, the

electrodes

7 and 8 are supplied with current so as to very suddenly and sharply increase the temperature of the tubular inlet 4 at the region where the

electrodes

7 and 8 are located, and it will be noted that the electrode 8 extends along a helix, at least in part. Thus, aninstant before the tube 4 is slipped off the tube 5 an impulse of heat is applied to the tube 4 at a temperature sufiicient to shrink the latter and the tube 4 is immediately slipped ofi the tube 5 so that immediately after leaving the tube 5 the tube 5 shrinks and thus closes the container. The shrinking of the tube 4 reduces its interior cross section 9 (FIG. 2) to such an extent that practically a complete seal is provided as indicated in FIG. 3. Moreover, because of the arrangement of the

electrodes

7 and 8, particularly the helical arrangement of the electrode 8, the shrinking of the material of the tube 4 takes place in such a way that it. contracts itself up into a labyrinth form, as shown at 4a in FIG. 3, and as a resuitof' this feature a complete seal of the interior of the container 1 from the exterior thereof is provided so that protection is provided not only against loss of the contents of the container 1 but also against the exterior atmospheric conditions.

FIGS. 4-6 diagrammatically illustrate the filling machine 10 which is provided with tubular outlet 5 described above and which is also provided with a tiltable support 11 which carries the container 1 during the filling thereof as indicated in FIG. 4. FIG. 5 shows a container after it has been filled and the instant after the impulse of heat has been applied to the tubular inlet 4 which has shrunk to the extent indicated in FIG. 5 during the substantially instantaneous removal of the container 1 from the filling machine 10. FIG. 6 shows the portion. 9a which has completely shrunk and closed so as to close off the interior of the container 1 from the exterior thereof.

It should be noted that instead of electrical heating, it is possible to provide the heating of the plastic material of a tubular inlet 4 by way of a gas such as air. For example, the tube 5 may be surrounded by a second tube 5' which is open at its right end and closed at its left end, as viewed in FIGS. 4-6, and the second tube communicates with a source of hot air and forms with the tube 5 an annular passage through which air may be directed to the right, as viewed in FIGS. 4-6. With such an atrangement at the instant when the container 1 has the position indicated in FIG. 5 a blast of hot air is provided at a temperature suficient to produce shrinking of the heat-shrinkable material as described above, and this arrangement also will provide closing of the tubular inlet 4, in the manner shown in FIG. 6. Moreover, the temperature applied to the heat-shrinkable material of. the tubular inlet 4 either electrically or by way of hot air may be high enough not only to produce shrinking but also to plasticize the material and render it at least to some extent fiuid so that the material will not only shrink. out in addition at the portion which shrinks the material will fuse together and form a complete closure so as to close otf the interior of the container 1 from the eX- terior thereof, to produce the arrangement shown in FIG. 6.

According to the arrangement shown in FIGS. 7-9 the tubular inlet is formed of a pair of

portions

40 and 41. The upper portion 41 forms approximately one half of the tubular inlet and extends longitudinally therealong from one to the other end thereof, and this upper portion 41 is made of a heat-shrinkable material such as any one of the materials referred to above, which will shrink when heated to a temperature of between 50 and C. The lower half 40 of the tubular inlet can be made of any suitable flexible material such as, for example, thin paper which may be creped and which may be provided with a waterproof coating. It has proved to be advantageous to use for the portion 40 of the tubular inlet a sheet of plastic which does not shrink such as, for example, polyethylene. Thelower layer 40 has side edges 42 which are bent over the side edges of the upper layer 41 and johied thereto as by gluing, fusing, heat-sealing, or the like.

The tubular inlet may be protected against possible injury from insertion of the filling tube, and for this purpose a covering 4-3 may be provided all around the left end of the

tubular inlet

40, 41, as indicated in FIGS. 7 and 9. Thus, the protective element 43 is folded back upon itself so as to form an inner groove which receives the left end of the

elements

40 and 41 which form the tubular element, and element 43 may be joined by gluing, heat-scaling, or the like to the

tubular inlet

40, 41, and then the element 43 itself may be fastened to the material of the container 1 so that in this way the element 43 also serves the function of fixing the

tubular inlet

41, 40 to the container 1. The element 43 may be made of paper, and the inner layer of the element 43 may be provided with longitudinally extending slits so as to facilitate the shaping of the element 43 to the configuration shown in FIGS. 7 and 9.

The

tubular inlet

40, 41 of FIGS. 7-9 may be closed, after the container 1 is filled, in any of the ways described above so that the material of the portion 41 will shrink. Of course, the material of the portion 40 will not shrink.

It is also possible, as shown in FIGS. 10 and 11, to provide for shrinking of the

tubular inlet

40, 41 of FIGS. 7-9 or of the tubular inlet 4 by placing the containers after they are filled on a conveyor 45 with the open tubular inlet 46 directed in a certain direction so that all of these tubular inlets 46 move along a predetermined path, and a tube communicating with a source of hot air, for example, is arranged to direct a stream of air against the containers as they are moved by such conveyor so that this stream of hot air will enter into the several inlet tubes 46 of the conveyors 45 moving successively past the stream of hot air and thus this stream of hot air will engage each of the

tubular inlets

40, 41 or 4 and shrink the heat-shrinkable material thereof to close the tubular inlets while the containers are conveyed.

With the

tubular inlet

40, 41 of FIGS. 7-9 the shrinking of the portion 41 causes the portion 40 to be pulled around the shrunk portion 41 and to assume a channelshaped configuration, the shrunk portion 41 being located in the channel formed by the portion 40, and with this arrangement a complete closing off of the interior of the container from the exterior thereof will be provided, so that a good seal is obtained. This seal may even be improved by exerting a pressure which urges the wall of the container, such as the to wall thereof, against the tubular inlet. In FIGS. 7, 9 the portion 41 of the tubular inlet is shown in dotted lines in shrunken condition.

While it is possible to locate the heat-shrinkable portion 41 of the

tubular inlet

40, 41 at the lower side of the tubular inlet, it is preferred to locate at the upper side as indicated in FIGS. 7 and 9 since it has been found that this location provides the best results.

It will be understood that each of the elements described above, or two or more together, may also find a useful application in other types of packages differing from the types described above.

While the invention has been illustrated and described as embodied in closable containers, 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.

Without further analysis, the foregoing will so fully reveal the gist of the present invention that others can by applying current knowledge readily adapt it for various applications without omitting features that, from the standpoint of prior art, fairly constitute essential char acteristics of the generic or specific aspects of this in vention and, therefore, such adaptations should and are intended to be comprehended within the meaning and range of equivalence of the following claims.

What is claimed as new and desired to be secured by Letters Patent is:

1. A container adapted to be fully closed after loaded with a desired material, said container comprising, in combination, an enclosure including a tubular inlet and completely closed except for said tubular inlet so that the enclosure may be loaded through said tubular inlet, said tubular inlet being made at least in part of a material which shrinks when heat is applied thereto so that after the enclosure is filled heat may be applied to said tubular inlet to shrink and close the same to thus completely close the enclosure.

2. A package comprising, in combination, a container adapted to be filled with a desired material and a tubular inlet connected to said container, said container being entirely closed except for said tubular inlet and said tubular inlet providing communication between the exterior and interior of said container and said tubular inlet being made of a material which shrinks when heat is applied thereto so that after the container is filled heat may be applied to said tubular inlet to shrink and close the same and thus completely close the container.

3. A package comprising, in combination, a container adapted to be filled with a desired material and a tubular inlet carried by said container, said container being completely closed except for said tubular inlet and said tubular inlet providing communication between the exterior and interior of the container so that the latter may be filled through said tubular inlet, said tubular inlet being made at least in part of a material selected from the group consisting of terephthalic acid ester foil, stretched low-pressure polyethylene foil, and stretched polypropylene foil, so that after the container is filled heat may be applied to said tubular inlet to shrink the heat-shrinkable material thereof so as to close said inlet and thus entirely close the container.

4. A package comprising, in combination, a container adapted to be filled and a tubular inlet fixed to said container, said container being completely closed except for said tubular inlet and said tubular inlet providing communication between the exterior and interior of said container so that said container may be filled through said tubular inlet, said tubular inlet including a pair of elongated portions joined to each other and extending longitudinally along said tubular inlet from one end thereof to the other end thereof, one of said elongated portions being made of a heat-shrinkable material so that after the container is filled heat may be applied to said one portion to shrink the same and thus close said tubular inlet so as to entirely close the container.

tainer, said container being completely closed except for said tubular inlet and said tubular inlet providing communication between the exterior and interior of said container so that said container may be filled through said tubular inlet, said tubular inlet including a pair of elongated portions joined to each other and extending longitudinally along said tubular inlet from one end thereof to the other end thereof, one of said elongated portions being made of a heat-shrinkable material so that after the container is filled heat may be applied to said one portion to shrink the same and thus close said tubular inlet so as to entirely close the container, said one portion of said tubular inlet forming the upper half of said tubular inlet.

6. A package comprising, in combination, a paper container adapted to be filled and fixed to a tubular paper member, said tubular paper member being in turn joined with a tubular inlet composed at least in part of a heatshrinkable material and providing communication between the exterior and interior of said container, said container being entirely closed except for said tubular inlet so that after the container is filled heat may be applied to said heat-shrinkable material to shrink the latter and thus close the container completely.

7. In a process for packaging material in a container which is completely closed except for a tubular inlet which is fixed to the container and which is made at least in part of a heat-shrinkable material, the steps of filling the container through said tubular inlet; and, after the container is filled, applying heat to said tubular inlet at a temperature sufficient to shrink the heat-shrinkable portion of the tubular inlet so as to close said inlet and thus completely close the container.

8. A packaging process comprising the steps of filling a container which is completely closed except for a tubular inlet which is fixed to the container and which is made of heat-shrinkable material through said tubular inlet; and after the container is filled applying heat to said tubular inlet along an at least partly helical area at a temperature sufficient to shrink the material of the tubular inlet so that when the tubular inlet shrinks as the result of application of heat thereto it will assume a labyrinth configuration and will completely close the container.

9. A packaging process comprising the steps of filling a container which is completely closed except for a tubular inlet which is fixed to the container and made of a heat-shrinkable material through the tubular inlet until the container is completely filled With a suitable material; and, after the container is filled, directing a stream of hot gas having a temperature sufiicient to shrink the material of the tubular inlet against the latter to shrink and thus close the same and in this way completely close the filled container.

10. A packaging process comprising the steps of filling a container which is completely closed except for a tubular inlet which is fixed to the container through the tubular inlet thereof, said tubular inlet being made of a heat-shrinkable material; and, after the container is filled, applying to said tubular inlet heat having a temperature sulficient not only to shrink the material of the tubular inlet but also to render the material of the tubular inlet fluid enough to cause the tubular inlet not only to shrink but also to fuse together in order to completely close the container.

11. A packaging process comprising the steps of filling a series of containers each of which is completely closed except for a tubular inlet which is made up at least in part of a heat-shrinkable material through the tubular inlet thereof; placing the thus filled containers on a conveyor with all of the tubular inlets thereof facing in the same direction so that the tubular inlets of the filled 7 3 containers move along a predetermined path on the References Cited in the file of this patent conveyor; and directing against the tubular inlets as they move on the conveyor along said path a blast of UNITED STATES PAThNTS hot air having a temperature sufficient to cause the heat- 2,790,286 Snyder Apr. 30, 1957 shrinkable material of the tubular inlet to shrink and thus 5 2,865,765 Allen Dec. 23; 1958 close each of the containers as they move on the conveyor. 2,918,958 Chandler Dec. 29, 1959