US2297375A - Container - Google Patents

Description

C. W. VOGT Sept. 29, 1942.

CONTAINER Filed Dec. 3, 1936 BY QW W wwf ATTORNEYS Patented Sept. 29, 1942 UNITED STATES PATENT OFFICE CONTAINER Clarence W. Vogt, Saugatuck-Westport, Conn.

Application December 3, 1936, Serial No. 113,969

7 Claims.

This invention relates to flexible-walled containers employed for the storage, shipment and dispensing of such flowable materials as liquids and solids in powder` or granular form.

In my copending application Serial No. 19,428, iiled November 6, 1936, I have illustrated a flexible-walled container which may be employed for various liquids such as lubricant oils for filling the crankcase of an automobile. I have also illustrated and claimed a dispensing device for receiving the container, and comprising a funnel having a puncturing member in the interior thereof for forming a drain opening in the bottom of the container, and a mechanism for stripping the contents of the punctured container as it is drawn out of the funnel.

'I'he ordinary type of flexible-walled container of at tubular form with no side k,infolds and with a straight seam across the bottom of the container, although highly desirable for certain purposes because of its comparative low cost of manufacture, has certain disadvantages, particularly when used for liquids. Inl such a container, the central portion of the bottom seam tends to break open due to the substantial internal pressure at said portion, and the fold edges of the collapsed container draw inwardly when filled as the container tends to assume a cylindrical form. Furthermore, in such a container, even if the drain opening is formed at the very bottom of the container adjacent to the bottom seam, liquid-retaining pockets may be formed on either or both sides of the drain opening, especially if the container is inclined in any direction, thereby rendering it difficult to discharge the entire contents of said container.

One object of the present invention is to provide a iiexible-walled container which eliminates the disadvantages referred to, and which is very inexpensive to manufacture.

Another object is to provide a container which is made from a sheet of iiexible material having its longitudinal opposed edges sealed together in a new and improved manner for effectively withstanding seal disruptive pressures of the contents of the bag during storage and transportation.

As a feature of the present invention, I employ a flexible-walled container of fiat tubular form, and without side infolds, and provide, across the bottom thereof, a seam convexly curved with respect to the outside of said container. By means of this construction, the pressure of the liquid contents is more evenly distributed along the entire length of the seam, so that the seal disvided with similar curved seals.

ruptive pressure of the liquid at the center of the seal is minimized. Furthermore, during discharging operations through a drain opening out opposite to the central portion of said seam, such as that formed by the container punctur-v ing device referred to, the liquid will flow downwardly along the curved side of said seam and through said drain opening, thereby preventing the formation of any liquid-retaining pockets, and assuring the discharge of the entire contents of said container.

As a further feature of the present invention, the upper portion of the container, before being charged, is provided with side seals which are curved oppositely from the bottom seal, and which are spaced apart to form a filling opening. After the bag is charged, this opening is sealed preferably along a curved section to follow approximately the curvature of the side seals, so that both ends of the container will be pro- A lled container so formed, can be lifted from either end, and may be stored and shipped without breaking the end seals. Furthermore, the outward projection of the corners of the filled container, and the inward buckling of the side sections of said iilled container, will be eliminated or substantially reduced, and the container will be much easier to store, ship, and handle.

Various other objects, features and advantages of the invention will be apparent from the following particular description and from an inspection of the accompanying drawing in which:

Fig. 1 is a front elevation of a container embodying the present invention and shown in co1- lapsed condition prior to being lled with liquid,

Figs. 2, 3 and 4 arev sections taken on the lines 2 2, 3-3 and 4 4, respectively, of Fig. 1, but somewhat enlarged,

Fig. 5 is a perspective view of the container after it has been filled and completely sealed, and

Fig. 6 is a section taken on the line 6--6 of Fig. 5, but showing the sight flaps in open position.

It must be understood that the thickness of the various wall layers of the ilexible container is shown in this drawing somewhat exaggerated, and that in practice all of these layers are very thin.

The containerv shown is made of laminated l sheet material, the inner layers or coating of which are of suchmaterial that when such inner layers are superposed and pressed together under heat, they will weld, vulcanize or hermetically unite. As an example of such materiahl may and preferably do employ a type of thin, flexible,v`

transparent, slightly elastic, impervious material sold under the name of Plioiilm and made from chlorinated rubber compound. 'I'his material has the thermoplastic characteristic of being readily vulcanized or sealed at a temperature of approximately 115 C., so that the overlapping sections thereof may be vulcanized or sealed together by the application of heat and pressure, even though the surfaces have been previously wetted by contact with liquids or moisture-carrying plastic material. Another material which may be satisfactorily used in some constructions and for some materials, is a moisture-proof cellulosic material of the type sold under the trade name Heat sealing Cellophane. As far as some aspects of the invention are concerned, a thin sheet material having a waterproof coating or layer such as that sold under the trade name "KoroseaP may also be used. Also, as far as certain aspects of the invention are concerned, other materials may be used, which may be fabricated into a casing by the use of adhesive or solvents to sealably secure adjacent surfaces of said material together.

The inner layer of the laminated sheet from which the bag is made will hereinafter be referred to as '"Plioiilm although it is to be understood that such a term, for the purpose of this invention, and as far as many aspects of the invention are concerned, may include any material of the type or character hereinbefore referred to.

In the specific construction shown, the container is fashioned from a flexible laminated sheet comprising an inner layer I2 of Pliofilm and an outer reenforcing sheet I3, cemented or otherwise secured thereto and made of paper or other similar flexible sheet material which will not be injuriously affected by application of sufficient heat and pressure to effect heating, fusing or vulcanizing of the Pliofilm.

In the process of making the container, the laminated sheet is bent around a mandrel, and the opposite longitudinal edges of said sheet are progresively brought and sealed together in parallelism to form an endless flat tube having a longitudinal seam |4, and a pair of opposed panels directly interconnected at their sides.

As a feature of the present invention, the longitudinal seam I4 of the tube has opposed sections of the Pliofilm autogenously bonded together, and is so constructed as to overcome any peeling or separating action between said bonded sections due to internal pressure action on said seal. For that purpose one longitudinal side of the outer paper layer I3 extends beyond the corresponding longitudinal edge of the inner Pliolm layer I2 to form a marginal extension I5, and the opposite longitudinal side of said inner layer I2 extends beyond the corresponding longitudinal edge of the outer paper layer I3 to form a marginal extension I6. The marginal outer layer extension I5 is cemented or otherwise secured to the outer face of the opposite longitudinal side section of the outer sheet I3, and the marginal Pliolm extension I6 is heat sealed to the inner face of the opposite longitudinal side section of the inner Pliofilm layer I2 to form an autogenous bond between said Pliofllm sections, said heat-sealing being effected by the application of heat and pressure.

The seam I 4 is preferably formed near one side of the container so as not to interfere with the sealing of the upper end of the container apparent h inafter.

Although the Plioiilm layer I2 is shown sealed together along its longitudinal edges, as far as certain aspects of the invention are concerned, said Pliofilm layer may be in the form of a seamless tube.

After the laminated sheet has been formed into a flat tube, it is heat-sealed transversely at spaced intervals along the tube in accordance with the desired 'length of the individual containers, to form the bottom and part of the top seals of the container.

The bottom of the container is closed by a seal |8 which is curved convexly with respect to the outside of the container and symmetrically with respect to the longitudinal axis of said container, and which extends to the sides of the container. 'Ihe seal I8 is substantially semi-elliptical in shape and is formed along a comparatively narrow strip by a heating element shaped in accordance with the desired shape of the seal I8 and acting against one panel of the flat tube, the opposite panel being backed by a suitable platen member. This heat-sealing operation causes the opposed facing Plioiilm layers to be autogeneously bonded together as shown in Fi g. 3, and forms a hermetic seal which is effective in withstandingl internal pressures.

At the opposite end of the container there are provided two similar side seals 20 transversely spaced with respect to the tube to leave a filling opening 2| therebetween, and formed by the application of heat and pressure in a manner similar to that already described, to autogenously bond the opposed Pliolm sections together along said seals 20. These side seals 20 have outer side sections 22 extending respectively to the sides of thc tube. and having curvatures similar to but reversed from that of the bottom seal I8. The inner side sections 23 of the seals 20 extend upwardly toward the upper end of the container to leave the filling opening 2| therebetween and to assure the sealing of the end of the container after the container has been filled, as will be described hereinafter.

'I'he endless tube may be transversely sealed along longitudinally spaced sections thereof in such a manner that each section includes a bottom seal |8 of one container length, and side seals 20 of the next successive container length, so that by cutting the tube transversely between said seal I8 and said seals 20, complete flat containers are formed as shown in Fig. 1.

If desired, the corners of the container as shown in Fig. 1 may be trimmed adjacent to the bottom and top seals as shown in Fig. 5 before'or after being filled through 'the opening 2| by any suitable means. The capacity of the container is sufficiently greater than the amount of liquid charged therein to permit variation in the volume of said liquid due to temperature changes, and prevent undue strain on the walls during handling. In the case of lubricant oil, for instance, I have found it desirable to make the capacity of the container about 25% greater than the volume of oil stored therein.

After the necessary charge has been delivered into the container, the air is exhausted from the head space above the charge level and the opening 2l is sealed by a closing seal 24 in which opposed sections of the Plioiilm layer I2 are autogenously bonded together as shown in Fig. 6. This closing seal 24 is effected by the application of heat and pressure in a manner already described with reference to the sealing of the bottom of the container, and is advantageously shaped to conform with the curvature of the side seal sections 22. It is desirable to have this closing seal 24 merge into the side seal sections 22 as shown in Fig. to form one continuous curved seal across the top of the container similar to the bottom seal I8. As the side sections 23 of the seal 20 have portions extending in the general direction of the length of the bag, the bag will be sealed by the transverse seam 24 intersecting the seals 23, even if there be some variation in the exact positioning of the seal 24 after the filling of the bag.

The container filled and completely sealed as shown in Fig. 5 will have curved seals at both ends and the liquid pressure on any one of these seals will be more evenly distributed along its length than in the case of straight seals. The container may be lifted from either end and when so supported the opposed panels of the container at its upper end will come together due to the exhaustion of air therefrom and will form at this end an easily graspable section. Furthermore, the container will have no protruding corners that might catch in any part of a funnel while it is being dropped therein for discharging purposes. Also, the container is so shaped when lled that it may be easily and effectively stored and shipped horizontally in a multiple compartment tray. Furthermore, whenthe bottom of the container is punctured opposite the central portion of the bottom seal, the liquid will flow downwardly along the curved sides of the seal and towards the drain opening thereof, thereby eliminating the formation of liquid-retaining pockets in said container and assuring a complete discharge of its contents.

The container is advantageously provided with sight windows through which the contents of said container may be observed. For that purpose, the outer paper layer I3 is slit to form ilaps 26 directly opposite each other on the container panels, these flaps being unattached to the Pliolm layer I2 so that they may be lifted as shown in Fig. 6 and the contents of the container observed through the transparent Pliofilm inner layers. These flaps 2B are advantageously V-shape and hang downwardly so that when the container is subjected to the operation of a stripping apparatus such as that previously referred to, these naps will not catch and be torn off.

Although the empty container may be stored and shipped in the condition shown in Fig. 1 with the opening 2| provided therein, a temporary seal may be provided across said opening to insure against contamination of the interior `of the empty container during storage and transportation. This temporary seal may be provided by heat-sealing across the seal sections 23 at the end of the container so that said temporary seal may be trimmed o before filling to provide the necessary filling opening, or may be formed by heat-sealing along a fine line between said seal sections so that the resultant line seal may be easily broken by merely separating the opposed sections of the container along said line seal.

Having thus described my invention, what I claim as new and desire to secure by Letters Patent is:

1. A package including a container of exible material provided at one end with a transverse hermetic seal convexly curved with respectto the outside of said container and provided at the opposite end with a pair of hermetic side seals \curved oppositely with respect to said first-mentioned seal, and extending inwardly from opposite edges of the container, but spaced apart to leave a filling opening, and a separate closing hermetic seal between said side seals and connecting said side seals. A

2. A normally flat collapsed container formed of a sheet of thermoplastic material and a sheet of non-plastic reinforcing material superposed and bonded together, said sheets being folded intermediate of their edges to form opposite parallel side walls, the fold being along one longitudinal side edge of the container and the edges of the thermoplastic sheet being sealed together lengthwise of and adjacent to the opposite side edge of the container, the thermoplastic sheet forming the inner layer or lining, the thermoplastic material being autogenously bonded together at one `end transversely along a section convexly curved to close the bottom of the container, and the thermoplastic material being autogenously bonded together along lines extending inwardly from the opposite edges of the container at the other end, to leave parallel juxtaposed intermediate portions which may be bowed apart to permit filling, and adapted to be autogenously bonded together to close the container after filling.

3. A normally fiat collapsed container including an inner or lining sheet of thermoplastic material and an outer reinforcing sheet superposed and bonded together, said lining sheet having opposite side walls closely juxtaposed and autogenously bonded together at one end of the container, and said opposite side walls being autogenously bonded together along lines extending inwardly from opposite edges at the other end of the container, said side walls between the ends of said bonding lines being adapted to be bowed apart to permit filling of the container, and adapted to be autogenously bonded together to seal the container after lling.

4. A normally fiat collapsed container including an inner or lining sheet of Pliolm and an outer sheet of paper superposed and bonded together, said lining sheet having opposite side walls closely juxtaposed and autogenously bonded together at one end of the container, and said opposite side walls being autogenously bonded together along lines extending inwardly from opposite edges at the other end of the container, said side walls between the ends of said bonding lines being adapted to be bowed apart to permit filling of the container, and adapted to be autogenously bonded together to seal the container after filling.

5. A normally at collapsed container including an inner or lining sheet of waterproof material and an outer reinforcing sheet superposed and bonded together, said lining sheet having opposite side walls closely juxtaposed and sealed together at one end of the container, and said opposite side walls being sealed together along lines extending inwardly from opposite edges at the other end of the container, said side walls between the ends of said sealing lines being adapted to be bowed apart to permit filling of the container, and adapted to be sealed together to hermetically close the container after filling.

6. A normally fiat collapsed container including an inner or lining sheet of waterproof material and an outer reinforcing sheet superposed and bonded together, said lining sheet having opposite side walls closely juxtaposed and sealed together at one end of the container, and said opposite side walls being sealed together along lines extending inwardly from opposite edges at the other end of the container, the opposed terminal portions of said sealing lines extending lengthwise oi' the container, the portions of the side walls between said terminal portions being adapted to be bowed apart to permit filling of the container, and sealed by a sealing line intersecting said terminal portions to hermetically close the container after filling.

7. A normally ilat container of laminated flexible material having an inner impervious thermoplastic layer and an outer reinforcing layer,

CLARENCE W. VOGT.

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