US3418783A - Method of sealing a container by vacuum - Google Patents

Description

Dec. 31, 1968 R. D. coLLoNs 3,418,783

METHOD OF SEALING A CONTAINER BY VACUUM Original Filed March 18, 1963 Ewa 1 1T/9.2 Jig-3 ATTORNEY United States Patent O 3,418,783 METHOD OF SEALIN G A CONTAINER BY VACUUM Rodger D. Collons, Smyrna, Ga. (5634 Sherborue Drive, Columbus, Ga. 31904) Original application Mar. 18, 1963, Ser. No. 265,662, now Patent No. 3,211,322, dated Oct. 12, 1965. Divided and this application Sept. 16, 1965, Ser. No. 487,813

1 Claim. (Cl. 53-22) ABSTRACT OF THE DISCLOSURE The invention relates to a method of packaging goods wherein a continuous deformable container body is filled with goods and is closed by closures at opposite ends. At least one of the closures incorporates flexurally resilient seal structure mounted from the annular edge of the closure. Partial evacuation of the container increases the effectiveness of the seal of the seal structure and also draws the container into supporting engagement with goods contained therein.

This invention relates to a closure and more particularly to a container and a self-sealing self-locking closure therefor.

This application is a division of Patent 3,211,322, entitled, Container and Closure Therefor, led Mar. 18, 1963, and patented Oct. 12, 1965.

For the economical transportation of goods in containers the container should be made of inexpensive materials and be economical of manufacture to cut down its initial cost. It should yalso be tough to withstand rough handling, water tight to prevent spoilage in transit or in dockage and light weight to minimize the shipment of dead weight. Additionally, and possibly most importantly, the container should be capable of being reused and/or knocked down to a configuration making it possible to reship the container to a point of use where it can be easily reconstructed and used again with little or no wastage. The container closure should also be simple, of light weight, easily installed, easily removable without injury to the container, self-locking and self-sealing. This invention provides a tough, impervious, water tight, knockdown, reshippable container having a self-sealing selflocking closure meeting the -above requirements.

It will be seen, therefore, that it is an object of this invention to provide a tough, impervious, reusable container which is economical of manufacture.

Another object of this invention is to provide a container capable of being knocked down to a minimum size for reshipment.

Still another object of this invention is to provide a light weight self-sealing closure.

A further object of this invention is to provide a slideon self-locking closure.

Still a further object of this invention is to provide a slide-on removable self-sealing and self-locking closure.

Yet a further object of this invention is to provide a container having a slide-on self-sealing closure, the selfsealing effect of which is enhanced by pressurization or partial evacuation of the container.

Other objects and advantages of this invention will become more apparent from the following description and drawings wherein:

FIGURE 1 is a side view of a container constructed in accordance with this invention;

FIGURE 2 is a fragmentary view taken substantially along line 2 2 of FIGURE l showing a preferred closure seal;

FIGURE 3 is a fragmentary view of an alternate form of the closure seal of FIGURE 2; and

FIGURE 4 is a fragmentary view of another alternate form of the closure seal of FIGURE 3.

Generally stated, this invention relates to a tough impervious plastic container capable of reuse or reshipment in a minimum of space, having a slidably engaged and disengaged self-sealing and self-locking closure.

More specically, there is shown in FIGURE 1 the container 6 having a preferably hollow cylindrical side w-all or body portion 7, although it could be rectangular. Body 7 is preferably formed by roll or bend forming a single piece of tough, pliable, impervious, sheet plastic approximately one-eighth inch thick such as polyethylene and welding the end edges together along the weld line or bead 8. For closing the top and bottom of the container body 7 there are provided the slidably engaged, self-sealing, selflocking, or self-gripping preferably plastic closure 20 each provided with a valve 21 whereby the container may be connected to atmosphere, pressurized, or partially evacuated. The container 6 thus formed may be unpacked upon reaching its destination simply by removing at least one of the closures and repacked for re-shipment. Alternately, if it is nceessary to reship the container empty to a point for re-use, the closures 20 may be slidably removed from the container bodies 7, the container body 7 cut as along the weld line 8, the container body straightened by the application of light pressure to the ends thus disconnected, and lastly the relatively flat closures 20 and container bodies 7 stacked for re-shipment. The containers 6 are readily reassembled for re-use by a reverse process. It will be appreciated from the above that the container 6, by reason of its unique construction, is adapted with equal facility for the re-shiprnent of goods or for re-shipment empty in a minimum of space.

Closures 20, best seen in FIGURE 2, each comprise a circular main body portion 22 connected at 23 to the seal structure 25. Forming of the seal structure 25 is accomplished by extruding or die casting a strip of plastic and cementing or welding the ends thereof together to form a circle. Although seal structure 25 and main closure portion 22 are disclosed as being separately formed, it is to be understood that they could as readily be formed structurally integrally as by die casting. Seal structure 25 comprises a top Wall 26 and spaced apart side walls or flanges 27 and 28 protruding from one side thereof. Flange 27 includes preferably three seals 29 which are Wide at their bases 29a and narrow to points at their terminal ends 29h. The seals 29 are formed to be curved such that their leading edges 29C facing the open terminal end of ange 27 are convex, their trailing edges 29d facing the top wall 26 are concave, and their terminal ends 29h are disposed rearwardly with respect to the main body portion thereof. Flange 28 is provided with seals 34 identical in configuration to the seals 29 in opposed relation thereto and accordingly the major features of seals 34 have been given reference numerical suxes corresponding to the identical major feature of the seals 29. Although it is preferred that the terminal ends 29b and 34b of seals 29 and 34, respectively, are not touching, these terminal ends could be touching if desired.

For closing the container 6, a closure 20 is mounted on each end of the container such that the side wall 7 slides into the seal structure 25 and in so doing depresses the seals 29 and 34 causing them to bend toward the top wall 26 such that a portion of their leading edges 29e and 34C adjacent their terminal ends 29b and 34b are in intimate sealing contact with the side Wall 7. The side wall 7 upon insertion into the closure seal 25 ilexurally bends the seals 29 and 34 along their lengths causing them to be resiliently, grippingly, and sealingly biased into engagement with the side wall 7. Although the biasing force of the seals 29 and 34 provides suicient resistance to removal of the closure 20 under most conditions, the

terminal end of side wall 7 may be provided with the bead 7a for reaction with the seals 29 and 34 to increase the resistance to removal of the closure 2t). One important attribute inherent in the seal structure 2S is that it provides excellent protection against leakage, regardless of the relationship of the pressure inside and outside the container 7. For example, if pressure P1 inside the container 7 is greater than pressure P2 outside the box, then for leakage from the box to occur, pressure Pl would have to depress seals 29 by forward bending and then depress seals 34 by reverse -bending which requires a substantially greater pressure than is required for forward bending because the seals must tiip back on themselves in their thick middle and lower regions. Conversely, if pressure P2 is greater than pressure P1 for leakage into the container 9 to occur, pressure P2 would have to depress seals 34 by forward bending and seals 29 by reverse bending. In fact, during reverse bending of seals 29 and 34, they are actually biased into firmer gripping and sealing engagement with the container 7, thereby increasing the efiiciency of the seal under such conditions. Accordingly, the interior of container 7 may be partially evacuated by connection of the interior of container 6 through valve 21 to a vacuum pump, not shown, to draw the seals 29 into tight sealing engagement with the container side wall 7. The effectiveness of seals 34, o'f course, is not affected by such partial evacuation. Another advantage obtained lby partial evacuation of the interior of container 6 is that it draws the flexible side wall 7 and closures 20 in tightly against loose bulk articles contained therein, for example, reduces its volume, and thus makes rigid the cargo. This ability to rigidize cargo is a quite valuable characteristic of the container 6 in that it eliminates shifting weight problems and cargo damage caused by relative movement between cargo units contained therein. Also, the creation of 4a partial vacuum in container 7 increases the resistance to removal of the closure 20; therefore, when it is desired to remove the closure, the interior of the container is first connected to atmosphere by operation of the valve 21.

Referring now to FIGURE 3, therein shown is a fragmentary view, identical in character to FIGURE 2, of an alternate form of the container closure shown in FIGURES 1 and 2 for closing the ends of container body 7. Closure 40 therein shown comprises the main body portion 41 secured at `42 to the seal structure 43. Seal structure 43 comprises a U-shaped mounting portion 44 which may be made of any suitable flexible or resilient metal or plastic material, having a top wall 45 and spaced apart anges 46 and 47 which depend therefrom. For sealingly and grippingly engaging the closure 40 with the container side wall 7, the plastic seal portions 51 and 52 are secured as by cementing to the interior side walls of flanges `46 and 47, respectively. It will be appreciated, of course, that the mounting portion 44 and seal portions 51, 52 could be made structurally integrally if constructed of the same material.

Seal portion 51 comprises a base 51a from which preferably three seals Slb are angularly inclined toward the top wall 45 in their installed position such that their terminal ends 51e are disposed rearwardly of the leading edge 51d thereof. The seal position 52 is identical to the seal portion 51, and the major features thereof will be given reference numeral suffixes corresponding to the identical major lfeatures of the seal portion 51.

For closing the container 6, a closure 46 is mounted on each open end of container body side wall 7 such that the side Iwall 7 slides into the seal structure 43 and in so doing depresses the seals 51b and 52b causing them 4 the seals 51b and 52b will permit uid leakage through them at a lower pressure differential across them because their bases are not built up. The seals Slb and 52b, however Iare quite suitable for most applications where exposure to high differential pressures is not contemplated.

Referring now to FIGURE 4, therein shown is a fragmentary view, identical in character to FIGURE 2, of an alternate form of the container closure shown in FIGURES l and 2 for closing the ends of the container body 7. Closure y60 therein shown comprises the main body portion 61 secured =at 62 to the U-shaped mounting portion y64 of seal structure 63. Mounting portion 64 may be made of any suitable flexible or resilient metal or plastic material and includes the top wall 65 and spaced apart lianges 66 and 67 which depend therefrom. For sealingly and grippingly engaging the closure 60 with the container side wall 7, the U-shaped seal portion 69 having a top wall 70 and spaced apart iianges 71 and 72 depending there-from is slidably mounted on the side wall 7. Flange 71 includes preferably three seals 73 which are wide at their bases and narrow to points :at their terminal ends. The seals 73 are formed to be curved such that their trailing edges facing the top wall 70 are convex, their trailing edges facing the open terminal end of fiange 71 are concave and their terminal ends are disposed rearwardly with respect to the main body portion thereof. Flange 72 is provided with seals 74 identical in configuration to the seals 73, and accordingly the major features of seals 74 will be given reference numeral suffixes corresponding to the identical major features of the seals 73.

For closing the container 6, a closure 60 is mounted on each open end of the container body side wall 7 such that the seal portion 69 slides into the mounting portion 64- whereby the seals 73 and 74 are depressed such that a portion of their leading edges adjacent their terminal ends firmly engage the mounting portion flanges 66 and 67 so as to be in intimate sealing contact therewith. It will be seen that the seals 73 and 74 are operated in the same manner as the seals 29 and 34 of FIGURE 2; however, the efficiency of seals 73, in communication with the interior of container 6, is increased by slight pressurization of container 6 by connection of valve 21 to a source of pressure fluid supply, not shown, or by filling the container with a liuid to be shipped such that a slight pressure exists in the container. Under such conditions, it will be appreciated, the container 6 could be provided with cargo strapping to prevent possible bulging of the container and to prevent the closures 60 from sliding oi after the passage of time.

It will be seen from the above that this invention provides a re-usable and/or knockdown container for the protected, economical shipment of goods having slidably installed and removed closures which are self-locking and self-sealing. Moreover, the container is constructed such that it may be partially evacuated for preventing relative movement between bulk articles contained therein without detriment to the sealing effect of the closure seals.

While particular embodiments of the invention have been illustrated and described, it will be obvious to those skilled in the art that various changes `and modifications may be made without departing from the invention, and it is intended to cover in the appended claim all such modications and equivalents as fall within the true spirit and scope of this invention.

What is claimed is:

1. A method of packaging goods comprising the steps of providing a continuous deformable container body side wall having opposite ends; sealingly engaging a closure with each of said opposite ends of said container body side wall; `at least one of said end closures incorporating flexurally resilient seal structure mounted from the annular edge of said closure which engages the interior surface of said container body side wall; lling the container thus formed with goods; and partially evacuating said container for drawing said exurally resilient seal structure 5 into rm sealing engagement with the interior surface of said container body side wall and for drawing said contaner into supporting engagement with the goods contained therein.

References Cited UNITED STATES PATENTS 3,117,873 1/1964 Bartels et al 53-22 X Rohdin 53-22 Garrow et al 53-112 X Palmer 53-22 X White 53-101 X Lassiter 53-22 X TRAVIS S. MCGEHEE, Primary Examiner.

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