US 3537229 A
Description (OCR text may contain errors)
w. F. PRENA v 73,537,229
7 PRODUCT SPACING STRUCTURE Filed Nov, 29, 1967 2 Sheets-Sheet 2 United States Patent 3,537,229 PRODUCT SPACING STRUCTURE William F. Prena, Norridge, Ill., assignor, by mesne assignments, to John Morrell & Co., Chicago, Ill., a corporation of Delaware Filed Nov. 29, 1967, Ser. No. 686,436 Int. Cl. B65b 31/00 US. Cl. 53-112 Claims ABSTRACT OF THE DISCLOSURE A pocket structure for a vacuum packaging machine wherein a product spacing, compartment dividing means is removably mounted in the pocket, with product holding means being formed integrally with the product spacing means. An elongate notch is provided in the product spacing means, so that packages that are joined in a double line operation can be severed while in the pocket structure.
BACKGROUND OF THE INVENTION The present invention relates to the vacuum packaging art; and more particularly to a vacuum packaging machine wherein a plurality of molding pockets are moved by a conveyor to a film drawing station where a lower layer of heated film is drawn into the pocket structure, then to a product loading station where a product is placed in the pocket structure upon the lower layer of film, and then to a sealing station where an upper layer of film is sealed to the lower layer of ifilm, while the interior of the package is evacuated. In a single line vacuum packaging operation, wherein a single package is molded in each pocket, the packets have in the past usually merely included a bottom wall, with continuous wall means extending around the sides and ends of the bottom wall. In a double line vacuum packaging operation, wherein two packages are molded in each pocket, it has been conventional in the past to provide the pocket structure with an integral, non-removable divider wall. It will be appreciated that with such an arrangement, if it is desired to convert from a single line vacuum packaging operation to a double vacuum packaging operation, or vice versa, it is necessary to remove and replace all of the pocket structures, and this has obviously required a lengthy shutdown of the machine. In the recent past, it has been proposed to obviate the time consuming conversion process by making the divider wall within the pocket structure removable, so that a single set of pockets can be used for both single line and double line operations. While this simple expedient has been successful in certain respects, it has also been unsuccessful in certain other respects, as for example when it is necessary or desirable to place a molding insert in one of the compartments of the pocket structure, as is necessary for certain shaped products. A further drawback of present day removable double line dividers is that, heretofore, it has not been possible to sever the joined packages made in a single pocket directly upon the vacuum packaging machine, and it has been necessary to transport the two joined packages to a further apparatus where the severing is effected.
SUMMARY The present invention provides a novel arrangement wherein the molding pockets are not only usable in both single line and double line packaging operations by virtue of the inclusion of a removable product spacing divider wall means, but the divider wall means also has product insert members formed integrally therewith to define a unitary assembly. The product insert portion of the product spacing assembly is shaped to correspond with the particular product being packaged, and thus the versatility of the vacuum packaging machine can be materially increased by merely having a plurality of sets of product spacing members having a variety of differently shaped inserts formed integrally therewith. The product spacing assembly of the present invention is readily removable from the pocket structure, and is releasably retained within the pocket structure by means of cooperating elements on the bottom wall of the pocket structure and the product insert portions of the product spacing assembly. The pocket structure of the present invention further includes a novel arrangement allowing a pair of adjacent packages formed in a double line operation to be slit directly upon the conveyor of the vacuum packaging machine itself, thus obviating the necessity of transporting the joined packages to a further severing station.
BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a top plan view of a first embodiment of the invention, with a portion of the product spacing wall and product holding insert being broken away for clarity of illustration;
FIG. 2 is a cross sectional view taken generally along line 22 of FIG. 1;
FIG. 3 is a cross sectional view similar to FIG. 2, and illustrating a modified form of product holding insert assembly;
FIG. 4 is a top plan vie-w similar to FIG. 1, and illustrating a modified pocket structure with a further embodiment of the product spacing assembly and holding means therein;
FIG. 5 is a cross sectional view taken generally along line 55 of FIG. 4;
FIG. 6 is a fragmentary, enlarged side elevational view illustrating the novel structural arrangement allowing joined packages to be severed directly upon a vacuum packaging machine;
FIG. 7 is a fragmentary plan view of the structure illustrated in FIG. 6, except that the product spacing assembly has been removed;
FIG. 8 is a fragmentary side elevational View similar to FIG. 6, and illustrating the use of an insert member during a single line operation; and
FIG. 9 is an enlarged perspective view of the insert member.
DESCRIPTION OF THE PREFERRED EMBODIMENT While this invention is susceptible of embodiment in many different forms, there is shown in the drawings and will herein be described in detail an embodiment of the invention together with modifications thereof with the understanding that the present disclosure is to be considered as an exemplification of the principles of the inembodiments illustrated. The scope of the invention will be pointed out in the appended claims.
The pocket structure is indicated generally at 10 in FIGS. 1-5, and is an upwardly open cup-like member including a generally rectangularly shaped bottom wall 11; a continuous wall means formed by parallel side walls 12 extending generally perpendicular with respect to bottom wall 11, and spaced parallel end walls 13 extending generally perpendicularly with respect to bottom wall 11. A vertical opening 13a is provided in each end wall 13 for reception of a vertically movable film edge clamping member, not shown, which can take the form of those illustrated in Myers application, Ser. No. 516,559, filed Dec. 27, 1965, now Pat. No. 3,397,507, and assigned to the assignee of the present application. Compressible means is provided on the upper surface of the pocket Wall means, and said means includes narrow elongate rubber strips 14 on the upper surface of side walls 12, and spaced, parallel narrow elongate rubber strips 15 and 16 on the upper strips 14-16 cooperates with further compressible means on the product spacing insert members to be hereafter described toallow a seal around the compartments formed within the interior of the pocket structure to be created, when engaged with a sealing head, such as that shown in the above mentioned Myers application.
A downwardly extending centrally located projection 17 extends transversely across the pocket structure on the lower surface of bottom wall 11, with a central openning 18 being provided in projection 17. Outwardly inclined passages 19 communicate with opening 18 and with chambers in the pocket structure on opposite sides of a divider wall to be hereafter described. Projection 17 is adapted to be engaged by a means for applying a vacuum to the pocket structure, so that a layer of film may be drawn into the pocket structure to form the lower portion of a package. A rib 20 is provided on the upper surface of bottom wall 11 midway between end walls 13, and extends transversely across the pocket structure between the side walls 12. A pair of spaced parallel ribs 21 extend laterally outwardly from the central rib 20, and are adapted to support the product spacing inserts, as will hereinafter appear. As will be apparent to those skilled in the art, ribs 21 assist in spreading the vacuum applied to the pocket structure through opening 18, so that the lower layer of film will be drawn into the pocket structure with a uniform force.
The bottom wall 11 of the pocket structure includes means for releasably retaining the product spacing and holding uneans therein, and to this end, bosses 23 extend downwardly from the lower surface of the bottom wall 11, on opposite sides of projection 17, with bores 24 in the bosses opening to the interior of the pocket structure. Spring clip members 25 are mounted in threaded openings in bores 24 and extend approximately to the level of the upper surface of the bottom wall 11. Spring clip members 25 cooperate with means to be hereafter described on the product insert portions of the product spacing structure to releasably retain the same within the pocket structure 10.
A first form of product spacing and product holding means is illustrated in FIGS. 1 and 2, and includes an upright wall 26 that extends perpendicularly between the side walls 12 of the pocket structure. As can be seen in FIG. 2, the lower end of wall 26 rests upon transverse rib 20 and divides the chamber within the pocket structure into two compartments of equal size. Compressible means, in the form of a rubber strip 27, is provided upon the upper surface of wall 26, so that when the sealing head referred to above is brought into engagement with the upper end of the pocket structure 10, a vacuum can be applied to the two compartments on opposite sides of wall 26. Product holding means 28 is formed integrally with wall 26, and in the embodiment of FIGS. 1 and 2,
.one such means extends outwardly from each side of wall 26. Each product holding means is in the form of a tray-shaped plate having a flat horizontal portion 29, a downwardly bent flange 30 secured to wall 26 by screws 31 or the like, an upwardly extending portion 32, and a horizontal portion 33 extending outwardly from the upper end-of portion 32 toward pocket wall 13.
A U-shaped bracket 34 is secured to the undersurface of each horizontal portion 29, as by spot welding or the like, and brackets 34 each include a horizontally disposed portion 35 that rests upon ribs 21, upright portions 36 extending upwardly from opposite ends of horizontal portion 33, and horizontal portions '37 that extend outwardly .from upright portions 36 and which are secured to the horizontal portions 29 of the product holding means. A detent ball 37a is carried by the horizontal portion 35 of each bracket 34,- and is releasably engageable with the spring clip 25 to positively, yet removably, mount the product spacing and holding means within the pocket structure 10.
From the above, it will be apparent that when the product holding means 28 is removed from the pocket structure 10, the pocket structure is suitable for use in a single line operation. When the product holding means 28 is positioned in the pocket structure 10, the pocket structure is capable of use in a double line operation. In
. both the single line and double line operations, a lower 7 operation, each product holding means 28 forms a mold that is shaped suitably to conform to the particular product being packaged, it being understood that the lower layer of film being applied to the pocket structure will assume the general shape of the particular product holding means 28. While the illustrated product holding means 28 forms a generally rectangularly shaped mold, it will be obvious that other configurations may be used, as desired.
During certain single line operations, it is also desirable to use product insert means, and an illustrative form is indicated generally at 38 in FIG. 3. Product holding means 38 includes a horizontally disposed upper portion 39 that extends between end walls 13, when the product holding means 38 is placed within the pocket structure 10. Generally vertically disposed portions 40 extend downwardly from the outer ends of horizontal portion 39, and horizontally disposed portions 41 extend inwardly toward one another from the lower end of each downwardly extending portion 40. Detent balls 41 extend downwardly from the center of each horizontal portion 41 of the product holding insert 38, and the balls 42 are engaged with the spring clips 25 to releasably mount the product holding insert 38 and the pocket structure 10. A generally U- shaped brace 43 extends transversely of horizontal portion 39, and brace 43 includes a horizontal portion 44 that rests upon the transverse rib 20 in the pocket structure 10. Brace 43 further includes spaced uprights 45 extending upwardly from opposite sides of central portion 44, and horizontal portions 46, which extend laterally outwardly from the upper end of each upright portion 45.
It will be well understood to those skilled in the art that after the product being packaged is placed within the product holding molds, upon the lower layer of film, in either a single line or double line operation, the product structure 10 then moves to a final sealing station where an upper layer of film is applied to the lower layer of film to complete the package or packages. At the final sealing station, a sealing head moves into engagement with the upper layer of film to press the same against the lower layer of film in the area of the rubber strip 14-16 so that a substantially sealed condition is created within the pocket structure. A suitable final sealing head is disclosed in the above mentioned Myers application, and such a head leaves a small unsealed portion adjacent each end wall 13 of the pocket structure, so that the interior of the formed packages can be evacuated. The sealing head also includes final sealing means for closing the small unsealed portion, after the desired degree of evacuation of the packages is achieved.
A further form of product holding means adapted for vuse in a double line operation is indicated generally at 47 in FIG. 4, and product holding means 47 includes a central vertically disposed divider wall 48. A rubber strip 49 is provided on the upper surface of divider wall 48, and extends from end to end thereof. As is clear from FIG. 4, the product holding means 47 is adapted to hold a circular product, and to this end, the product holding means includes circular horizontal portions 50 on opposite sides of divider wall 48. A detent ball 51 extends downwardly from the lower surface of each portion 50, and cooperates with a spring clip 25 to releasably retain the product holding means in the pocket 10. A cylindrical wall 52 extends upwardly from the outer periphery of each horizontal portion 50, and a horizontal upper wall portion 53 extends outwardly from the upper end of each cylindrical wall 52. Ribs 54 extend generally radially outwardly of cylindrical wall 52, and downwardly from each horizontal wall 53. The ribs 54 adjacent the divider Wall 48 include foot portions 56 that are secured to the divider wall 48 by screws 55.
While the pocket structure 10 illustrated in FIGS. 4-9 is substantially identical to that illustrated in FIGS. 13, it differs therefrom in that it includes means allowing the two packages formed in a double line operation to be severed directly upon the conveyor of the vacuum packaging machine. To this end, an upwardly facing rectangular notch 57 is provided in each side wall 12 of the pocket structure 10 in alignment with the divider wall 48. A generally U-shaped recess 58 (FIG. 6) is provided in the outer surface of each side wall 12 adjacent notch 57. Divider wall 48 includes rectangular extensions 59 of reduced width at each end, which are seated in the notches 57, when the product holding means 47 is placed in the pocket structure 10. As is evident from FIG. 4, the outer ends 49a of rubber strip 49 are also reduced in width so as to be substantially coextensive with the extensions 59. An upwardly opening central slot 60 is provided in the upper end of wall 48, and slot 60 extends from end to end of wall 48, including extensions 59. From the above, it will be apparent that a package severing means, such as a knife having a blade member with a thickness slightly less than the width of slot 60, can be mounted at a suitable place on the vacuum packaging machine, such as on the sealing head, to sever the two joined packages as they move with the conveyor past the severing means.
When the pocket illustrated in FIG. 4 is utilized in a single line operation, inserts 61 (FIGS. 8 and 9) are inserted in notches 57; and inserts 61 are formed of a compressible material, such as rubber, so that an effective seal can be created around the periphery of the packages during the final sealing operations. As can be best seen in FIG. 9, inserts 61 include a generally rectangular central portion 62 having a size substantially the same as notches 57, so as to disposed the upper surface of the insert 61 in substantially the same plane as the rubber strips 14 upon the sides 12 of the pocket structure. Inserts 61 further include generally U-shaped flanges 63 at opposite sides of central portion 62, and as is evident from FIG. 8, flanges 63 have a size which corresponds to the size of recesses 58.
1. A pocket structure for use in a vacuum packaging machine comprising: a bottom wall having an opening therein through which a vacuum can be applied; continuous wall means extending upwardly from said bottom wall including a pair of spaced parallel walls at opposite sides of said bottom wall and cooperating therewith to define a chamber; product spacing means mounted in said chamber for dividing said chamber into plural separate product receiving compartments, said product spacing means including an upright central divider wall extending generally transversely of said side walls and plural product holding means attached thereto, with one such product holding means being positioned in each compartment; means for releasably retaining said product spacing means in said chambers; compressible means on the upper end of said wall means and said central wall, whereby the top of said chamber and/or said compartments can be sealed; and aligned notches in the upper end of each side wall, with said divider wall having an extension at each end thereof seated in one of said notches.
2. A pocket structure as set forth in claim 1 wherein an elongate groove is provided in the upper surface of said divider wall and extensions.
3. A pocket structure for use in a vacuum packaging machine comprising: a bottom wall; a pair of end walls extending upwardly from opposite ends of said bottom wall; a pair of side walls extending upwardly from opposite sides of said bottom wall, each side wall spanning the extent between said end walls and cooperating with said end walls to define a continuous wall means; means defining a notch in each of said side walls, said notches being in alignment with one another; compressible means on the upper end of said end walls and side walls; and a removable insert in each of said notches, said inserts being formed of a compressible material.
4. A pocket structure as set forth in claim 2 including a pair of removable inserts of compressible material positionable one in each of said notches to form a continuous pocket perimeter when said product spacing means with the central divider wall is not used.
5. A pocket structure as defined in claim 3 including a divider wall positionable between said side walls and having an extension at each end thereof positionable in said side wall notches upon removal of said inserts, and compressible material on the top of said divider wall which lies coplanar with the compressible means on said end and side walls.
References Cited UNITED STATES PATENTS 1,708,304 4/ 1929 Elliott 249131 3,343,332 9/1967 Mahafiy et a1. 53-112 X 3,353,218 11/1967 Cloud et a1. 53184 X TRAVIS S. McGEHEE, Primary Examiner US. Cl. X.R.