Method and apparatus for sequentially packaging materials into units of desired volume

FIELD OF THE INVENTION ¹⁽¹

The present invention is generally concerned with the packaging of products that can be force filled into a receptacle. More particularly, the invention concerns packaging of discrete quantities of material without necessarily requiring '5 metered dispensing.

“Forced filling” as contemplated herein, refers to any techniques where the material being filled into a receptacle exerts a force against the receptacle. Extrusion filling clearly satisfies this definition. In addition, it is intended to include filling arrangements wherein the weight of the material alone applies the force, as in the case of gravity loading from a hopper.

There are many products which can effectively be packaged by forced filling of containers. These products range from food items such as sausages to large bulk items such as agricultural produce. In almost all instances, it is desirable to provide packages or units having uniform dimensions and containing a predetermined quantity of material. Obviously, it is desirable to automatically provide a finished packaged product at the output of the machine. This invention is specifically directed to packaging techniques involving the use of elongated containers which are subsequently subdivided and sealed to yield individual packages.

Among the important features in the handling of products of the nature described, is the utilization of labor. Although the packaging of some products can be completely automated, others require the employment of manual labor for such steps as the final sealing of each package. Generally, when individual packages are created from one large unitary container, it requires that the rate of filling be exactly synchronized with the rate of package handling by the operator or succeeding apparatus. However, efficient use of machines and operators makes it preferable to have the filling rate substantially independent of the package handling rate.

It is an object of the present invention to provide an improved method of packaging materials wherein the filling rate and individual packaging rate need not be synchronized.

Another object of the invention is to. provide an improved method of packaging materials by extrusion wherein the extruded material need not be metered in order to insure that a predetermined quantity of material is deposited in each of the final packages produced.

Yet another object of the present invention is to provide an improved force filling process wherein a plurality of preliminary package units may be filled successively without completing the packaging until some subsequent time.

Another aspect of the invention is to provide unique apparatus for carrying out the process of force filling elongated containers.

It is another object of the invention to provide an improved apparatus for force filling an initially axially compressed elongated container.

It is another object of the invention to provide an improved apparatus for force filling an initially compressed elongated container having selected portions thereof secured together to prevent axial extension.

The above objects of the invention, as well as others not specifically recited, will be more fully appreciated from the following detailed description which is made in conjunction with the drawings. This detailed description will also bring out further unique features and advantages of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates a container being filled with a material from a hopper in accordance with one embodiment of the invention;

FIG. 2 is a cross-sectional view taken transversely through a container-filling apparatus according to another illustrative embodiment of the invention;

FIG. 3 is an illustration showing the operation of sealing and cutting the area between individual packaging units;

FIG. 4 is an illustrative lay-out illustrating the use of a severance line within the clamped area of a container of the type used with the invention; and

FIG. 5 illustrates a further embodiment of the invention showing apparatus for filling containers constructed in the manner to be fully described.

DESCRIPTION OF PREFERRED EMBODIMENTS OFTHE

INVENTION

DESCRIPTION OF THE PRIOR ART

With respect to the larger produce handling packaging techniques heretofore known, it will be recognized that in general these techniques do not involve the continuous force filling of large containers that are subsequently subdivided. Rather, in the packaging of bulk items, it is conventional to fill individual packages and handle them on a one-by-one basis.

On the other hand, in the handling of foodstuffs, such as sausages, it is conventional to extrude the sausage meat into casings which are subsequently tied off at prearranged intervals. Existing sausage handling equipment includes means for extruding metered charges of filling materia! into a tubular casing which has been previously longitudinally compressed or shirred over a filling horn. The metered charges are subsequently separated automatically by tying off the spaces therebetween. Operator intervention is not necessary in this packaging process; however, the automatic tie-off operation must be synchronized with the extrusion process in order to permit its continuous functioning.

SUMMARY OF THE INVENTION

The invention relates to a packaging process involving the force filling of compressed elongated containers and the subsequent creation of individual packages having predetermined quantities of material, and to apparatus particularly suitable for use in carrying out the unique packaging process.

FIG. 1 shows a container 10, positioned upon a filling ap5Q paratus and partially filled with a material IS. The material 15 is initially stored within a hopper 16 and is extruded or forced through a horn cylinder 17 into the container 10 under the action of an impeller means 18. The major portion of container 10 is longitudinally compressed over horn 17. Throughout the 55 specification and claims, reference will be made to the “folds” of the compressed container. It should be understood that folding, pleating, shirring, etc. may be used depending upon the material from which the container is made, the dimensions of the container, and the nature of the filling apparatus.

In the particular container shown in FIG. 1, an end closure 19 is provided. Thus, as material is extruded under the action of impeller 18, it forces the container to extend. Clamping means 13 are provided at various positions along the container and hold together a predetermined number of folds, prevent65 ing their axial extension under the effect of the extrusion process. The amount of material retained by the clamping means 13 is determined by the amount of material required to effect transverse closures of the containers. The length 11 between clamping means is determined by the amount of 70 material to be packaged. Quite clearly, the amount of material packaged will depend upon not only the length but also the volume of the container and this depends upon the particular cross-sectional shape used. Although FIG. 1 illustrates a substantially tubular container construction, it is recognized that other cross sections may be employed.

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Reference is now made to FIG. 2 which illustrates a container mounted upon extrusion apparatus after several lengths of the container have been filled. The apparatus includes a supply portion 20 terminating in a cylindrical horn 23 that is connected to the supply portion via conical sides 22. A means 21 which may be either a ram or screw-type impeller system is employed to force material 24 through horn 23. The particular input means for supplying material to the apparatus is neither germane nor shown. Container feed units are mounted upon the sloping sidewalls 22, in at least two diametrically opposed positions. The unit shown in the upper portion of the figure is typical and includes a stationary member 25 rigidly secured in any appropriate fashion to wall 22, and a releasing member 26 pivotally attached to stationary member 25 at point 27. A spring 28 is engaged at some stationary point, such as on member 25, and also is secured to pivoting member 26. The end of member 26 is normally biased in a downward position as a result of the contraction of spring 28. This end, 29, rests against the container material that has been initially compressed onto horn 23. Underneath end 29, a projection 30 on the external surface of horn 23 may be provided. During extrusion of material 24, the pressure of the material acting against the end of the container causes it to stretch and it is pulled off the horn between ends 29 and 30. It will be understood that the pressure of spring 28 and the shape of ends 29 and 30 are so arranged that generally a single fold is permitted exit at one time. Furthermore, it will be appreciated that the clamping means 13 will also be permitted to pass through the space between ends 29 and 30 as a single unit. Thus, the container as it is extruded will appear roughly in the ³⁰form shown in the right portion of FIG. 2.

It will be noted that the extreme right end of the container 10 in FIG. 2 is shown clamped by means 41. The initial end section of any container may either be permanently closed or closed after the container is mounted. In many instances, the containers are prepared as elongated pleated tubes and after they are mounted upon the horn of an extrusion device, the end is sealed off. Thereafter the process of filling may proceed. The particular manner in which the end is sealed may vary greatly and may employ any of the techniques that are conventional in the art today. For example, a simple wire clamping means 41 may be employed or, it the material is suitable for heat sealing, this may also be utilized.

As the container is filled it travels toward the right under the 45 influence of the extruded material. Depending on the size of the container and other factors, such as weight and supporting surface conditions, auxiliary equipment or supporting members may also be employed. In still other instances, such as where large agricultural crops are being handled, it may be 50 deemed advantageous to move the extrusion or filling vehicle and leave the container on the field as it fills. There is no need for sealing off the individual packages until some time in the future when the labor or a more propitious time for performing such a task is available.

When the individual packages are to be formed, it is simply necessary to remove clamping means 13 and stretch the previously clamped portions of the container. With reference to FIG. 3, it will be seen that this stretching of the previously clamped portion leaves sufficient material for closing the ends 60 of each unit. FIG. 3 illustrates the actual closure being effected at two points by the use of conventional twisted wire. After the closures have been completed, the portion of the container therebetween is severed at point 40.

It will be appreciated that in order to most expeditiously 65 subsequently separate the packages, it may be desirable to provide initially for this separation by weakening the area to be ultimately severed, with perforations or the like. Thus, FIG. 4 illustrates a container 10 adapted to be folded or crimped substantially along lines 45. The region 46 is that which will be 70 secured by the clamping means. Substantially in the center of region 46 is a perforating line 47 which can be easily tom apart. The clamping means is much stronger longitudinally than the axial force exerted on the fabric during filling, and therefore there is no need for concern that the perforations 47 75 will longitudinally weaken the container during the filling process. ⁶

Another apparatus for feeding material in accordance with the invention, is shown in FIG. 5. The apparatus in this Figure is substantially similar to that shown in FIG. 2, with the exception of a different container release mechanism. In the present instance, the mechanism comprises a spring means 50 having an outwardly inclined extension 51 at the end of horn 23. As a result of this extension on the spring means, as the container is forced forward during filling the extension tends to grip each fold of the crimped container until sufficient force is applied by the extruded material to force the fold into axial extension. Once again, it will be noted that due to the unique provision of the clamping means 13 on the external surface of the container, the entire clamped portion will be fed out at the same time and the packaging process may proceed in the manner previously described.

The clamping means 13 may take many forms. Their function requires strength in the longitudinal direction of the container that is sufficient to prevent opening of the clamped folds during filling. In addition, they should be easily removable to conveniently facilitate the individual packaging steps. The number of clamps used to secure a particular plurality of folds is optional.

In recapitulation, it will be recognized that the process of the present invention includes the steps of extruding material into a foreshortened selectively clamped package, removing said clamps and stretching the container between the areas previously clamped, sealing the central portion of said extended area at two axially spaced points, and severing said extended portions between these seals.

Several embodiments and aspects of the invention have been described. It should be understood that this invention is not limited to the use of particular materials. It is contemplated that modifications in regard to these features of the invention may be made by those skilled in the art without departing from the spirit and teaching herein. All such modifications are intended to fall within the scope of the appended claims.