US 3297152 A
Abstract available in
Claims available in
Description (OCR text may contain errors)
Jan. 10, 1967 A. P. coRELLA ETAL 3,297,152
VALVED MIXING CONTAINERl 0R PACKAGE 3 Sheets-Sheet l Filed March 4, 1964 E CbAJELLn, 5'. scf/News@ 7 .Kuren/roes'.
AQ ma? WiL/,QM
Jall- 10 1967 A. P. coRELLA ETAL 3,297,152
VALVED MIXING CONTAINER OR PACKAGE Filed Marsh 4, 1964 s sheets-sheet 2 pr//UQ 1.0 'QELLHJ 717/24 /HM 5. 50m/Eme@ INVENTOR-S.
Jan. 10, 1967 A. P. coRELLA ETAL 3,297,152
VALVED MIXING CONTAINER' OR PACKAGE Filed March 4, 1964 3 Sheets-Sheet 3 Maf ,1.9. /j/ ra. 31?.
AIHI/ .H @peut f7, MLA/mw 5. SCW/venas? INVENTOR.
Arrow/sys United States Patent O 3,297,152 VALVED MIXING CONTAlNER R PACKAGE Arthur P. Corella, North Hollywood, and William S. Schneider, Glendale, Calif., assignors to V. Wayne Rodgers, South Pasadena, Calif.
Filed Mar. 4, 1964, Ser. No. 349,267 6 Claims. (Cl. 206-47) The present invention relates generally to containers and packages having ilexible walls, and more especially to a container w'hich may be used as a package for the purpose of merchandising a product to which the user will later add .a liquid and will then mix the added liquid and the product together by flexing or kneading the walls of the bag, the container being provided with a one-way valve through which the liquid may be introduced into the package by the user.
Many different types of products are now sold in a dry form and are to be mixed by the user with a liquid, such as water, as a step in the subsequent processing for use of the original material. Examples include cake mixes, pie crust mixes, pancake mixes, and other food products which are sold in dry form and are to be 4mixed with milk or water by the user. Other examples where mixing of product-s is contemplated may be found among various nonfood products such as plaster of Paris, cement mixes, and various liquid plastics of the type to which a liquid catalyst is to be added.
One well known manner of using products of this character involves emptying the product out of the package in dry form into a suitable mixing bowl or the like, adding a desired liquid, and stirring or agitating the liquid and the dry mix together with a suitable implement. It is a convenience to the user if products of this character are sold in packages having ilexilble Walls and into which the proper amount of added liquid may be placed, the liquid and the dry product being mixed in the package. After the desired mixture is secured, it is then ejected from the package through an opening in the package wall which is formed for that purpose. Many advantages accrue to the user, particularly the saving in time and trouble of cleaning up a bowl or vessel in whic-h the mixture was prepared, since the flexible wall package now constitutes a disposable mixing container.
For this type of service, various designs of containers have previously been made. In some instances a constricted opening is provided through which iluid is introduced and this opening must then be held closed in some manner by the user during the mixing operation. If one hand is employed to hold the opening closed, only one hand is free to do the mixing.
Other designs of packages for this type of service with inlet passages in the form of a llat tube providing the only entrance are more satisfactory but still have not been entirely successful in practice. These flattened tubes rely on keeping the opposing walls in contact to exert a one-way valve action, and are sometimes referred to as flutter valves. Known designs of such packages are subject to occasional failures, and even an occasional failure is sufficient to prevent commercial acceptance of such a package. The chief problem has been to provide a one-way valve which remains securely closed during the mixing operation. In known designs that use, or are adapted to, thin, llexible, limp, packaging materials, there has `been no means holding the valve closed. Hence the valve is not always closed when the mixing period starts, with the result that some of the contents enters the passage and escapes by reverse flow through the valve-controlled passage.
Sometimes it appears as if the spreading apart or other relative movement of the outer walls of the package dur- "ice . ing the mixing operation causes a separation of the elements of the valve, thus opening an escape passage for the contents of the package. In other designs, it is apparently possible for a fold or wrinkle to form in one of the walls of the passage, thus allowing the package contents to enter the valve and spread the walls apart. Whatever the reason, once even a small amount of the contents of the package enters the valve structure, this material tends to hold the valve open and allows escape of additional material by reverse flow through the inlet passage.
Attempts have been made to remedy this situation by adding a valve structure that is made of a rigid material, e.g., a flap valve, or one made of another flexible material, such as rubber. The comparatively thick, elastic walls of the rubber hold themselves in mutual conta-ct, closing the passage. However, rubber is a material foreign to the material from which the package is made. It is not a thin, inexpensive packaging material that can be heatsealed or used in standard packing machines. Hence, rubber creates special problems of handling and of connecting the valve to the packaging material that make such valves too costly to be widely used, if not impractical. This is especially true of wide valves, using a substantial amount of material.
The same container Without any dry contents, may also be used as a disposable or temporary receptacle to receive and hold liquids. If the liquids are waste material, the container may be thrown away with the liquids. For example, the container constructed with a narrow inlet passage is adapted to receive a catheter tube .for hospital use as a urinal. When the tube is withdrawn, the container becomes self-sealing and may be `disposed of along with its contents. Many other uses of the container are also possible, since it, for example, may be used as a temporary storage or single-use container which, having ilexible walls, always takes up a minimum space as it shrinks with the decrease in the volume of the contents.
Thus, it is a general object of the present invention to provide a novel design of a package of the general type containing a valve controlled passage through which liquid may be introduced into the product-holding space within the package and the product .therein and the liquid mixed together by kneading or llexing the outer walls without causing the valve to open and allow the escape of any of the contents during the mixing operation.
It is also an object of the present invention to provide a package or a container of this general type having a valve controlled inlet passage through which water or any other fluent substance may `be easily introduced into the package but which serves to prevent accidental escape of the package contents through the passage.
Another object of the present invention is to provide a package of this general type containing a one-way valve structure in which the walls forming a passage for introducing a substance into the package remain in contact at all times after introducing the substance, thus forming a one-way valve which is reliable in operation but simple in construction.
A further object is to provide a package of this type containing a one-way valve structure, such that the package can be hermetically sealed to safeguard the contents against loss of moisture or contamination by the entry of foreign matter `but yet is of such character that the hermetic seal can be lbroken easily by the user to open the inlet passage while leaving the valve structure intact.
Still another object of the present invention is to design a package of this character which can be easily manufactured entirely from heat scalable films or webs on high-speed, automatic machinery of t-he form-and-iill variety, thus making the package relatively inexpensive and easily available in large quantities, a characteristic essential to a commercially worthwhile package.
These objects of the invention have been attained by providing a container comprising a pair of opposed, flexible outer walls for defining between them a productreceiving space; wall means defining an inlet passage extending inwardly of the container from one edge thereof and communicating with said product-receiving space, said wall means comprising a pair of opposed, flexible walls of which at least one wall is in addition to the outer walls; and means associated with the wall means holding the opposed walls in mutual contact to prevent reverse flow of fluid out of the product-receiving space, yet allowing the fluid to flow through the passage into the productreceiving space.
This same container may Ibe used as a package for merchandising a product by placing a product in the product-receiving space, the ultimate user adding the required amount of the desired liquid and then mixing the liquid and the product together within the package.
The means associated with the wall means for holding the opposed walls in mutual contact may take various formations. In a simple configuration of a package, the wall means defining the inlet passage are provided with an arched configuration which holds the two opposed walls together, the wall nearer the center or curvature being under a slight compression and the other wall under a slight tension which is sufficient to hold the walls in mutual contact at all times except when a liquid is flowing through the inlet passage. Alternatively, other means may be employed, as will be more fully explained later, including a plurality of small spot seals substantially at the inner end of the inlet passage, or a charge of static electricty which attracts the two walls to each other, or any other means which holds the wall in mutual contact.
The present invention is directed to low cost packages or containers that use only thin, very flexible standard packaging Webs of materials that are heat sealable on one or both sides. Such materials are completely limp and are not resilient; Iand can be used with high-speed automatic form and fill machines.
How the above and other objects and advantages of the present invention, as well as others not specifically referred to here, are attained, will be better understood by reference to the following description and to the drawing, in which:
FIG. 1 is a side elevation of a package having flexible walls and a one-way valve structure, a portion of one of the outer walls being broken away for purposes of illustration.
FIG. 2 is an enlarged fragmentary longitudinal section on line 2 2 of FIG. 1.
FIG. 3 is a transverse section on line 3 3 of FIG. 1 showing the inlet end of the liquid passage.
FIG. 4 is a transverse section on line 4 4 of FIG. l.
FIG. 5 is a transverse section on line 5 5 of FIG. 1.
FIG. 6 is an enlarged fragmentary longitudinal section on line 6 6 of FIG. 1.
FIG. 7 is a fragmentary side elevation of a package illustrating a variational embodiment of the invention in which the inner walls and the outer walls are respectively integral with each other. I
FIG. 8 is a fragmentary longitudinal section on line 8 8 of FIG. 7.
FIG. 9 is a side elevation of a variational construction of the package, with part of one side wall broken away.
, FIG. 10 is an enlarged fragmentary longitudin-al section on line 10-10 of FIG. 9.
FIG. 11 is an enlarged fragmentary longitudinal section on line 11 11 of FIG. 9.
FIG. 12 is a transverse section on line 12-12 of FIG. 9.
FIG. 13 is a fragmentary vertical section similar to FIG. 2 illustrating a modification thereof.
FIG. 14 is a side elevation of a container illustrating another variational embodiment of the invention.
FIG. 15 is a transverse section on line 15 15 of FIG. 14.
FIG. 16 is a fragmentary enlarged vertical section on line 16 16 of FIG. 14.
FIG. 17 is la fragmentary side elevation of a container illustrating another variational embodiment of the invention.
FIG. 1S is a vertical section on line 18 18 of FIG. 17.
FIG. 19 is a side elevation of a container illustrating another variational embodiment of the invention in which the outer wall of the container forms one wall of the inlet-passage means.
FIG. 20 is a top elevation of the container of FIG. 19.
FIG. 21 is a transverse section on line 21-21 of FIG. 19.
FIG. 22 is a side elevation of a container illustrating another variational embodiment of the invention in which two inner walls forming the inlet passage are folded back on themselves.
FIG. 23 is a top elevation of the container of FIG. 22.
FIG. 24 is a transverse section on line 24 Z4 of FIG. 22.
FIG. 25 is a fragmentary side elevation of a container illustrating a variational embodiment of the invention having reclosable closure means for the inlet passage.
FIG. 26 is a vertical fragmentary section on line 26 26 of FIG. 25.
There will be seen in FIG. l a side elevation of a generally flat envelope-like package 10 constructed according to the invention. As may be seen in FIG. 2, the package comprises a pair of flexible outer balls 11 and 12 which are made of thin sheet material. The package is shown as being rectangular in outline since this shape is most commonly and easily produced on packaging machines; but it is to be understood that the invention is not necessarily limited to this or to any particular shape of package.
The two opposed, outer walls 11 and 12 are of similar shape andare joined together to form an interior productcontaining space 14 within which is a quantity of a dry powdered product 15. In the fabrication of the package illustrated these two outer walls are originally separate, .as t-hey are cut from separate webs, and they are joined together around the entire periphery of the finished package in order to provide a seal around the entire product space 14. Generally speaking, the invention is independent of the particular means employed to join together these two walls, and consequently the word joined is used in a broad sense. For example, the walls may be integral with each other as in FIGS. 7, 19 and 22 or they may be joined together through an intermediate member, as will be explained. This exemplary package assumes the common practice to make a package from two separate sheets which are joined together by heat seals 16 along the opposite longitudinal margins of the package and by heat seals 18 and 18a at the two opposite transverse margins or ends of the package.
In order to form the seals 16, 18 and 18a by the application of heat and pressure, the outer walls are made of sheet material which is heat sealing on the inner face. As typical of the thin flexible materials that may Ibe used for this purpose, there may be mentioned cellulose acetate film, commonly known as Cellophane, coated on the inner face with a layer of polyethylene. The polyethylene is a thermo-plastic material which enables the two walls to be sealed together over an area to which heat and pressure are applied. Other films of a thermoplastic nature or films with other thermoplastic coatings such as vinyl resins, or rubber hydrochloride, may be used instead. In addition, the outer walls may have an outer layer of metal foil or other material, as may be desired.
' Disposed between the two outer walls are means defining an inlet passage, comprising two inner Walls 21 and 22. These two walls `are also formed of flexible sheet material which, for reasons which will become evident, is heat sealable on both faces. The two inner walls are rectangular in shape and both extend entirely across one dimension of the package, preferably the shorter dimension or width. The dimension of the inner walls perpendicular thereto is less than the corresponding dimension or length of the outer walls, as is shown clearly in FIGS. 1 and 2, so that the inner edges 21s and 22s of the Walls are spaced from one end of the package closed by seal 18a. The inner walls are so located with reference to the `outer walls that three edges of the inner wall substantially coincide with edges of the outer walls along three sides of the package. Thus, the two inner walls are sealed between the outer walls throughout the full length of the one end seal 18 'and also over portions of the two opposite side seals 16. This condition illustrates a situation in which the outer walls are joined together through an intermediate element of the package, though not in direct contact with each other. f
This latter condition is illustrated in FIG. 2, wherein end seal 18 includes all four walls. The two inner walls 21 and 22 are sealed at opposing faces to each other over the area of seal 16. Each of the outer walls 11 and 12 is also sealed to an outer face of the walls 21 and 22, respectively. The seal between the two inner walls at this area closes the end of the liquid passage hereinafter described while attachment of the outer walls to the inner walls in part of the means providing a hermetic seal around the package enclosing the product-containing space 14.
As shown particularly in FIGS. 2 and 6, each of the inner walls 21 and 22 is joined to the adjoining outer wall 11 and 12, respectively, by =a relatively long, narrow heat sealed area 24. Sealed areas 24, extend entirely across the package between side seals 16 and are generally parallel to and spaced from end seal 18. As will become obvious, the two inner walls are not seal-ed together at 24, although the two heat seals 24 are preferably opposite each other as shown.
Both inner walls 21 and 22 are attached to each other by two seal areas 25 and 26 which are preferably narrow, elongated heat seals which are spaced apart from each other and which extend inwardly from or near seal 24. From a functional standpoint, seals 25 and 26 can join seals 24, but for ease of manufacture it is preferred that seals 25 and 26 approach seals 24 and then turn outwardly to join side seals 16. The short segments of the two side seals between seals 25 or 26 and seals 24 provide continuity between transverse seals 24 and the two spaced seals 25 and 26. In general, the two seal areas 25 and 26 start from the inner or lower edges 21s and 22s of walls 21 and 22 and extend across these walls toward the opposite edge to a position comparatively near the opposite edges thereof. These latter edges are somewhere yabove or beyond seals 24 depending on the exact construction, but are at the edge of the package in FIG. l. Located between the two inner lwalls and bordered by the two seals 25 and 26 isa filling passage P with its inlet end adjacent the outer edges of the two walls and extending inwardly of the package to place its exit end at the inner edges 21S and 22s of these walls. The two seals 25 and 26 taper inwardly in order to give `a general funnel-shape to the passage with a larger end being at the inlet end. At the exit end of the passage the two seals 25 and 26 have parallel or substantially parallel, terminal sections at their closest approach to each other.
Both inner walls 21 and 22 are also connected to one of the outer walls. In the construction illustrated, this outer wall is wall 12. This -connection of both inner `walls to the one outer wall is most conveniently accomplished by connecting the three walls together over the seal areas 25 and 26. This permits the connection of the inner walls to the outer wall to be made at the same time and over the same area as the -connection of the two walls to each other.
Thus, the two seal areas 25 and 26 provide a connection of the two inner walls to outer wall 12 at each side of the inner or exit end of the filling passage P formed between the two inner walls. The spacing between the two seals 25 and 26 at the exit end of the passage P is slightly less than the length of material in each of the two inner walls between the same two seals. The result is that there is a Vsmall amount of slack or looseness in the two inner walls at the exit end of the liquid passage that gives to the inner walls an arched configuration even when the outer wall 12 is pulled taut. This condition is shown clearly in FIGS. 4 and 5 at 29 in somewhat exaggerated and idealized form for purposes of illustration. It will be realized that, because of the limp, flexible nature of the inner walls, they do not assume any given or constant shape at the exit end of the passage. Nevertheless, the effect is to create a configuration of the .inner walls that holds the two opposed walls in mutual contact.
This construction produces a one-way valve construction that is effective in preventing the contents from entering the liquid passage from lthe interior space of the package during mixing while at the same time permitting liquid to be introduced into the product space through the unsealed passage P. Since both inner walls `are attached to one outer wall, there is no tendency for the inner Walls to be separated as a result of the outer walls being spread apart by internal pressure.. Furthermore, the slack in the two inner walls just described forms a loose fold 29 in the two walls producing tension and compression in the walls 21 and 22, respectively, tending to keep the two walls -always in contact with each other, thus 'resisting entry of material from the pro-duct space into the liquid passage without at any time resisting ow of liquid through the passage when introduced into the inlet end.
Not essential to the proper 4operation of the package but convenient to the user, are the two seals 27 and 28. These seals extend from seals 25 and 26, respectively, to the side seals 16 and are located at or closely adjacent to the lower edges 21s and 22s of the inner walls. Seals 27 and 28 `seal the inner walls together and also to outer wall 12 for the purpose of preventing the contents of the package from working up into the confined spaces within the package between inner wall 22 and the adjoining outer wall 12. In the absence of barrier seals 27 and 28, a small amount of the contents can become trapped during mixing in these parts of the package. This is undesirable since it often interferes with proper mixing of the contents and also results in a certain amount of unecessary waste.
The completed package with its contents hermetically sealed in it appears as shown in FIG. l. In order to use the package the end seal 18 is removed by cutting all four walls transversely across the package substantially along the line 3 3 between seal Iareas 18 and 24. This results in free access to the inlet end of the filling passage P as shown in FIG. 3. The passage can be opened up by spreading apart the inner walls to give a funnel-like yshape to the passage, and a suitable amount of any desired liquid can then be poured easily into the package, the liquid fallin-g down through the passage P between inner walls 21 vand 22. The liquid flows easily by gravity as its weight forces the inner ywalls apart, providing easy entry of the liquid into the product-containing space 14..
The liquid and the dry product are now mixed together by kneading or flexing the walls of the package to provide suitable mixing or agitation of the contents of the package. After a suitable mixture of the contents is achieved, the semi-fluid contents are now squeezed out of the bag through an opening created expressly for this purpose. This can easily be done by cutting off a corner of the package along the line 30, thus creating a second opening of easily controlled size through which the contents can be discharged at a fully controlled rate.
Mixing action can be carried out easily because of the Very flexible nature of the thin, pliable walls of the package. It will be seen that substantially the entire volume of the package interior is available for the mixing operation. The inner walls, because of their connection to outer wall 12, both lie against the one outer wall and the normal pressures exerted by the contents on these walls during the mixing operation tend to press the inner walls against each other. Also, because the two inner walls are connected to only `one outer wall, the relative motion of the two outer walls ycaused by kneading during mixing exerts no force on the inner Walls tending to separate them to allow escape of the product. The result is that the inner walls remain in contact with each other during the mixing operation and effectively close the inlet passage to reverse flow and escape of the contents.
For purposes of disclosure, the package has been described as being originally filled wit-h a dry, fluent product 15 to which a liquid is to be added. It is equally within the scope of the invention to fill the packagel initially with a liquid or semi-liquid material or to add a fiuent powder or dry substance through passage P.
The package described can be made from four separate webs, the packages being severed from the ends of the webs as they are completed. One method is to feed into the machine two webs in parallel, opposed relation to provide the two inner walls. The outer walls are then fed in one on each side of the two inner walls, so that the outer walls are in parallel, opposed relation to each other. Assuming the webs moved from right to left in FIG. l, continuous heat seals are formed at 24. Each seal 24 joins one inner wall to the adjoining or overlying outer wall. The seal 24 is at an area relatively adjacent one edge of the inner web and extend in the direction of web travel.
Next the walls are joined by heat seal 1S along one margin. This stabilizes the positions -of the webs relative to each other, preparatory to placing the seals 25 and 26 `forming the filling passage. These latter seals are preferably formed by a single die that places si-multaneously the seal 25 of one package and seal 26 of the adjoining package. Alternatively, a single die may place both seals on a single package at one time. The seals 27 and 28 are placed by the same die; and, as mentioned above, not only are the two inner walls sealed to each other but both are connected to one outer wall. This involves removing the other outer wall from the action of the sealing die, as by folding the wall back enough to allow the die to operate inside that wall `and contact the inner wall thereby exposed.
To insure that there is excess material in the inner walls between the parallel terminal sections of yseals 25 and 26, a forming shoe is inserted from one open end of the package between the inner wall and the outer wall to which it is sealed, in the example walls 22 and 12, while the webs are stationary. The shoe is of a size to produce the desired curved or arched configuration 29 of the inner walls. After placing seals 25 and 26, the shoe is retracted allowing the webs to advance.
Next the side seals are placed, joining the outer walls together in a manner to partially enclose the productcontaining space but leaving one end of the package open. The product is introduced through this open end, after which final seal 18a is placed to hermetically as in FIG. l or it may be omitted as shown in FIG. 8 since the integral character of the walls closes the package. The inner walls 21a and 22a are likewise made from a single sheet or web folded at 32 to bring the two Walls into opposing positions. Since the two inner walls are integral with each other at their outer edges, it is not necessary to `seal them together, as at 18, as a means for closing the upper end of the filling passage P.
As before, the seals 25a and 26a join the inner walls 21a and 22a together and to outer wall 12a. The seals 25a and 26a define the inlet passage and flare outwardly at their outer ends to merge with the side seals 16. The segments of the side seals 16 between the seals 25a or 26a and seal 24 serve to define in part the complete fluid passage. The same arched configuration 29 provides means holding the opposed passage Walls in mutual contact.
As in the first described form, the filled package is opened by removing the end of the package including the two folds 31 and 32, thus destroying the continuity of the inner and outer walls respectively. This is done typically by cutting across the package within the area of seal 24 or between seal 24 and the near end. This breaks the hermetic seal around the contents lby removing completely the end sealed area 18 and opens the passage P to admit water or other liquid at the wide end and conduct it into the product space 14.
From the above description, another variational `form of the invention will be obvious without detailed description. The package 10c may be. constructed Without extending the inner walls into the end sealed area 18. In other words, the inner walls 21 and 22 may have their upper or outer edges positioned at or just beyond the sealed area 24, as shown in FIG. 13. However, the construction shown in FIG. 2 is favored as it makes for easier and surer handling of the Webs in a high speed machine.
The embodiments of t-he invention thus far described have been designed for ease of manufacturing from continuous web stock. Each package as completed is severed `by a single cut from the following webs. Web travel is transverse to the longer dimension, that is, from right to left, or vice versa, in FIG. 1; and consequently the inner and outer walls are equal in extent in this direction, or substantially so. It is obvious however, that the portions of walls 21 and 22 laterally beyond seals 25 and 26 have no functional utility in respect to the inlet passage and that these portions may be gmlited. A package 10b of this type is shown in FIGS.
Referring to FIGS. 9-12 it will be seen that outer walls 11b and 12b are duplicates of walls 11 and 12 and are similarly joined by marginal heat sealed areas 16, 18 and 18a. Inner walls 2lb and 22b are now shaped to conform more or less closely to the outline of the funnel-shaped passage P to be provided by and between these two inner walls. As already described, the sealed areas 25b and 26h join the inner walls together and the walls are also attached both to one outer wall, wall 12b, by seal areas assumed to coincide with areas 25b and 26b, though they may not, depending on the manner of making the package. Seals 25b and 26b are now along opposite margins of walls 2lb and 22b and the latter do not extend into side seals 16.
Each of the inner walls 21b and 22b is attached to the adjoining outer walls 11b and 12b respectively over the se-al area 24h. This seal extends across the `full width of the inner walls and is extended at 34 at each end to meet side seals 16 to prevent escape of product after tlhe end seal 18 has been removed to open the passage P for filling.
The foregoing description has related to a filled package as an example illustrating most fully the advantages of the present invention. From that description it will be selfevident that the `invention has utility as an inexpensive, disposable container. As such it will be made and merchandised without any product in it. If two or more prod.- ucts are to be mixed, they will be added in turn by the user. A container of this character is produced by the very simple change of omitting from the package of FIG. 1 all, or at least a large part, of end seal 18 between the two side seals 16. The resulting container is similar to the above-described packages in the state produced by cutting off the end portion of the package along a line between seals 24 and 18, in the vicinity of section line 3 3 of FIG. 1.
`Investigation of various designs leading to the present invent-ion has indicated that any uncontrolled Wrinkle or fold formed in one wall of the passa-ge during the kneading operation opens the valve. The above-'described forms of the present invention are designed to place a controlled curvature in both walls of the filling passage at the outlet end. The curved or arched configuration holds the walls normally in mutual Contact. During the kneading operation pressure of the contents against the outside of the curved walls holds them firmly together. Connections of the inner walls to one outer wall alone eliminates any relative movement of the inner walls caused by relative movement of the outer walls.
There is shown in FIG. 14 a container which is constructed in the same manner as the package illustrated in FIG. 9, except as noted below. The package terminates at its upper end Iat the seal 241)I which seals the inner walls 21e and 22C of the valve to the outer walls 11e and 12C, respectively. Seals 40 and 41 are located similarly to seals 2Sb and 26h since they join at their edges the two inner walls 21C and 22C to fonm the inlet passage P and also join walls 21e and 22e to outer wall llc. Seals 4t) and 41 extend upwardly to terminate in the area of transverse seal 24h.
The container of FIG. 14 differs from the package of FIG. 9 in that the slack or looseness in the walls is now located at' 42 in outer wall llc. This produces an arched configuration 42 in the outer wall as shown clearly in FIG. 15 (the curvature being exaggerated for purposes of illustration) while the two inner walls 21C and 22C are straight. The arch or loop in the outer wall 11e tends to straighten out under the influence of one or more forces. This may tbe merely the weight or bulk of the contents distending the outer walls, or it may be tension in the outer wall produced during the kneading action, that tends to stretch the outer wall and thereby straighten out the curved configuration at 42. Ilhese forces, alone or in combination, apply tension to inner walls 21C and 22C through the two heat seals 4t) and 41, which tension straightens the inner wall members and thereby holds these wall members in mutual contact. Of course, at any time fluid introduced into the upper end of the inlet passage P between walls 21C and 22C can overcome this force and pass be tween the walls to enter product-receiving space 14, but the forces acting on the wall members Zlc and 22C are suicient to ihold the walls in contact at the exit end of the passage and thereby prevent reverse ow of uid out of the product-receiving space.
A further modification of the Iinvention is shown in FIG. 17 in which the container 10c is formed as shown and described in FIG. 14 but without the arched configuration at 42. In this embodiment of the invention, the means associated with the inner wall members 21d and 22d for holding these opposed Walls in mutual contact cornprises a plurality of island seals as indicated at 45 in FIG. 17. These island seals illustrated are small seals, perhaps no more than one-sixteenth (/gth) inch in diameter which tack together the opposed walls 21d and 22d forming the fluid inlet passage; but other shapes, arrangements and numbers of the seals may be used. Generally, they are :but a small fraction of the distance between seals 40 and 41.
It has been found that the most prevalent cause of failure in known designs of the one-way valve is the formation in one wall of a small wrinkle or fold. To cause a failure,
such a wrinkle or fold extends generally parallel to the axis of the passage, which is the vertical axis of the package in the position illustrated, and pass through the exit end of the inlet passage. The formation of such folds or Wrinkles can be prevented by small seals as indicated at 45. These island seals are spaced from any other heat seals and serve as means for Iholding in mutual contact the walls 21d and 22d forming the inlet passage. At the same time these seals allow the walls to separate to Ilet iiu'id flow freely from the upper end of the passage P into the product-receiving space 1 4, 'because of the exible nature of the walls dening this passage. Seals 45 hold the walls together to prevent reverse flow of uid out of the productreceiving space during the kneading or mixing action.
FIG. 19 shows a variational embodiment of the invention which differs in various ways, as explained below, from the containers and packages already described.
One of these differences resides particularly in the outer wall construction. In the container 107 the two outer walls 51 and 52 are obtained from a single web which is folded longitudinally at the center. Consequently, enclosing the interior product-receiving space requires making only three heat seals at 47, 48 and 49, the fourth side of the container being formed Iby a 189 degree fold 50 in the web, where the two outer walls 51 and 52 are integral with each other. The presence of the fold Sti in the outer wall makes possible a difference in the arrangement of the wall means defining the inlet passage. In this package, the wall means defining the inlet passage a-gain comprises a pair of wall members opposed to each other, `but one of the wall members is the outer wall of the package, whereas t-he outer wall member is a single inner wall member. The sheet forming the inner Walls 54 and 55 is folded over upon itself along a median line at 56 so that the two halves of the sheet overlie each other. This inner sheet is then placed inside the outer wall with the fold 56 therein at the fold 5&1 in the outer walls.
Each half 54 and 55 of the inner wall member is joined to the opposing outer wall 51 and 52 respectively, by a heat seal 57 which is spaced farther from folded edge 50 at the upper end of the seal than it is at the lower or inner end. Heat seal 47 across one edge of the container seals outer walls 51 and SZ together where they oppose each other; and across the remainder of the container it seals the inner walls 54 and 55 to each other and to one of the outer walls, the latter being wall 52 in FIG. 20'. For at least a portion of the distance between seal 57 and the edge of the container at fold 50, wall 51l is not sealed to the inner wall 54- in order to leave unsealed the end of inlet passage P, as may be seen in FIG. 20.
This construction produces an inlet passage which, in its entirety, is of U-shape and lies Ibetween the pair of Walls provided by the lfolded inner Wall members 54, S5 and the opposing portions of the outer Walls of the package. However, since lone-half of the passage is closed at its upper end by the seal at 47, only lone leg of the U-shape is fully active, which is that portion. :of the enti-re passage lying between inner Wall 54 and outer wall 51 and shown as 'being lopen at P in FIG. 20. By inclining heat seal 57 as shown in FIG. 19, the passage tapers from a wider mouth to a relatively narrow discharge opening at its inner end.
In actual manufacture, heat seals 57 are placed while the web forming lthe outer walls and the inner sheet are fiat so that the two wall forming members are joined to each other before folding over on themselves through degrees to provide the Ifolds therein indicated at 50 and 56, respectively. As a consequence of this construction, the curved or arched wall closer to the center of curvature, in this case the inner walls 54 and 55, has a slight compression in it while the other or outer wall has a slight tension. As previously mentioned, these forces in the two mem-bers are sufficient to cause the walls to be held in mutual contact as shown in FIG. 21, thus normally closing the inlet passage at its inner end. However,
l l due to the flexible nature of these walls, they can separate at any time to yallow the weight of entering liquid to force them apart, permitting the liquid to flow through the `inlet passage into the product-receiving space 14 of the container.
After the outer web is folded and while the container is being formed, heat and pressure are again yapplied over areas which may coincide more or less with the areas of -seals 57 to seal together at 58 the inner opposed faces .tion which resembles in many ways the container illustrated in FIGS. 19-21. Again, the two out-er walls 51 and 52 are obtained from a single folded web, the web -being folded over on itself through 180 degrees, 4forming the fold at 50l on one edge of the package. The two outer walls are joined by three heat seals 47, 48 and 49 tto enclose the interior product-receiving space 14.
The walls means defining the inlet passage now comprise a pair of inner wall forming members 60` and 61. The innermost one of the two wall members 60 is folded over on itself along a median line. The other one of these wall members 61 is folded over around the Wall member 60 so that each of the members is in a general U-shape with one outside of and opposing the other (FIG. 24).
Alon-g the top edge of the package at seal area 47 the two half sections of wall member 61 are sealed respectively on the outside to the inner lfaces of outer walls 51 and 52, as may be seen in FIG. 23, while walls 51 and 52 4are sealed to each other over a portion of seal 47. Inside of the wall member 61 is the folded wall member 60 of which the two inner opposed faces are sealed together along their entire top edge; and one-half of this wall member is then sealed to an opposing `face of wall member 61. The other halves of the two wall members 60 and 61 are not sealed to each other in order to permit spreading theml apart at the edge of the package for access to inlet passage P.
In the manufacture of the package, the two wall members 60 and l61 are brought into mutually overlying and opposing relation and then sealed together at two locations along the heat sealed areas 64, while the two sheets are fiat. After they are thus connected to each other, the two sheets together are fol-ded over through 180 degrees into the U-form shown in FIGS. 23 and 24 and are then inserted in the container in a position, as in FIG. 22, to be sealed to the outer walls thereof along the seal area 47 Iat one ed-ge of the completed container.
After the wall means defining the inlet passage are placed between walls 51 and 52, heat and pressure are then applied to seal these two inner wall members to at least one of the outer walls at an area preferably more or less coincident with heat sealed areas, 64, as shown in FIG. 24. The two areas 64 are assumed to now overlie each other. Also, preferably, the inner opposing faces of wall member l60 are sealed together over this same narrow elongated area in order to stabilize these Wall members in the configuration which they assume in order to define the inlet passage.
Because these two wall forming members are folded over after being lfastened together, it will be realizied from the foregoing description that compression and tension forces, respectively, in the two wall members 60 and 61 at the fold in them hold the wall members normally in mutual contact at the exit end of the inlet passage P, in order to prevent flow of fluid out of the interior product-receiving space 14.
With this configurati-on of the wall means forming the inlet passage, the passage P is located between opposing faces of the two inner Wall members 60 and 61. In its entirety, the inlet passage has a U-shape, as was the case with the container in FIG. 19. However, the upper end of the passage is closed at one side of the U-shape by the seal between the wall mem-bers 60 and 61 in the area 47, while the other leg of the U-shape is open at the end, as shown in FIG. 23. Liquid or other fluent material introduced into the upper end of the passage can force the walls apart because of their flexible nature and flow into the product-receiving space. It actually can iiow through the entire U-shape of the passage. For ease of introduction, the seal areas 64 are inclined in such a manner that passage P is larger at the inlet end than at the inner discharge end, thus having a general funnel shape.
As explained above, when the container is filled with a product it is generally desirable to hermetically seal the interior space by providing a seal or closure entirely around the product-receiving space 14. For this purpose, the top seal 18 is provided in the embodiment of FIG. l. When only an empty container is made land sold, it may be desired at times to provide the container with the elosure means vfor the inlet passage which can be manipulated by the user after inserting contents into the container to seal the package against the entry of foreign matter from outside. A container of this character is illustrated in FIG. 25 which is constructed in the same manner as the container of FIG. 14 except for the addition thereto of a narrow band of pressure sensitive adhesive 66 on the inner face of one or both of the wall means defining the inlet passage P. The presence of this pressure sensitive adhesive permits the inlet passage to be firmly closed by the application of manual pressure to the outside walls of the package in the area of the adhesive.
This construction has the advantage that it permitsfthe user to close the package for any purpose. It also prevents Ibreathing losses. This adhesive is preferably placed near but spaced in `from the entry end of the inlet passage in order that the walls of the inlet passage may be grasped at the edge of the package `and pulled apart to break the adhesive seal and open the passage. Although somewhat removed from the discharge end of the inlet passage, this pressure sensitive adhesive is another example of means Iassociated with the wall means defining the inlet passage for holding the opposed walls in mutual contact to prevent loss of the contents by reverse iiow through the passage.
As previously mentioned, the present invention is concerned with containers and packages that are made entirely from very thin iiexible webs or films, often only one mil, usually less than three mils, thick. Consequently, the walls are not only very flexible but completely limp and they are movable in response to forces of very small magnitude. This characteristic enables the small forces generated by the previously described structure to hold the walls of the attened tube forming the inlet passage, in' mutual contact at the inlet end of the passage, thereby preventing reverse flow during mixing or kneading of the contents.
As long as the two walls defining the inlet passage are in contact, the pressures on them from the contents during mixing tend to close the passage, as they are applied externally to the passage walls. The present invention provides means holding the passage walls together, under normal conditions, at the inner or discharge end of the passage. Hence, access to the passage is denied the contents, while access is possible when the walls separate, even slightly, as by the formation of a small wrinkle in one Wall. The forces holding the walls together are very small, perhaps only a fraction of one percent of the externally applied forces during mixing; but they are fully effective as long as they are in operation before mixing starts.
As a further example of such a force, the walls may be held together by a charge of static electricity induced by rubbing or stroking the walls, either inner or outer. Any film having a very high dielectric value, such as vinylidene chloride commonly known as Saran, holds a static charge generated by rubbing the lm; and two such charged films are held together by their mutual attraction.
From the above disclosure it will be apparent that Various other modifications and re-arrangements of the container structure are possible within the spirit and scope of our invention. Accordingly, itis to be understood that the foregoing description is considered to be illustrative of, rather than limitative upon, the invention as defined by the appended claims.
1. A container, comprising:
a pair of opposed, ilexible outer walls defining a product-receiving space;
wall means delining an inlet passage extending inwardly of the container from one edge thereof and communicating with the product-receiving space, said wall means comprising a pair of opposed llexible walls of which at least one wall is in addition to the outer walls;
a strip of pressure sensitive adhesive extending across the inlet passage on the inner face of one of the opposed walls of the last mentioned pair of walls to hold said opposed walls in mutual contact normally to close the passage to reverse llow of iluid out of the product-receiving space yet allowing the walls to be separated to permit a lluid to tlow through the passage into the product-receiving space.
2. A container as in claim 1 in which also includes means maintaining a curved configuration in the last mentioned pair of opposed llexible walls producing therein stresses holding the opposed walls in mutual contact adjoining the inner end of the inlet passage.
3. A container, comprising:
a pair of opposed llexible outer walls defining a product-receiving space;
wall means delining an inlet passage extending inwardly of the container from one edge thereof and communicating with the product-receiving space, said wall means comprising a pair of opposed flexible walls of which at least one wall is in addition to the outer walls;
and a plurality of island seals connecting together the last mentioned pair of opposed walls at positions within the inlet passage whereby the opposed walls are held normally in mutual contact yet can separate to allow a fluid to llow through the passage into the product-receiving space.
4. A package comprising:
a pair of opposed, ilexible outer walls defining a product-receiving space;
a quantity of a product in said space;
wall means defining an inlet passage extending inwardly of the package from one edge thereof and communicating with the product-receiving space, said wall means comprising a pair of opposed flexible walls of which at least one wall is in addition to the outer walls;
a strip of pressure sensitive adhesive extending across the inlet passage on the inner face of one of the walls of the last mentioned pair of walls to hold said opposed walls in mutual contact to close the passage to reverse llow of iluid out of the product-receiving space yet allowing the walls to be separated to permit a fluid to flow through the passage into the productreceiving space.
5. A package as in claim 4 which also includes means maintaining a curved conguration in the last mentioned pair of opposed flexible walls producing; therein stresses holding the opposed walls in mutual contact adjoining the inner end of the inlet passage.
6. A package, comprising:
a pair of opposed, flexible outer walls dening a product-receiving space;
a quantity of a product in said space;
wall means defining an inlet passage extending inwardly of the package from one edge thereof and communicating with the product-receiving space, said wall means comprising a pair of opposed flexible walls of which at least one wall is in addition to the outer walls;
and a plurality of island seals connecting together the last mentioned pair of opposed walls at positions within the inlet passage whereby the opposed walls are held normally in mutual contact yet can separate to allow a fluid to tlow through the passage into the product-receiving space.
References Cited by the Examiner UNITED STATES PATENTS 2,679,969 6/ 1954 Richter 229-35 2,697,531 12/1954 Hood 229-625 2,800,269 7/ 1957 Smith 29-625 2,804,257 8/ 1957 Hasler et al 229-625 3,106,159 10/1963 Abramson 229-62.5 3,195,801 7/1965 Symons et al. 229-625 FOREIGN PATENTS 1,184,550 2/1959 France.
LOUIS G. MANCENE, Primary Examiner. THERON E. CONDON, Examiner. W. T. DIXSON, JR., Assistant Examiner.