US3474843A - Blow-molded containers - Google Patents

Description

0d. 8,1969 0. a. MARIE, 3,474,843-

aww-uowm: coummims med Aug. 28, 1967 2 Sheets-Sheet 1 Jl mvzuron as DAVID B. mums ms ATTQBNEY Lr-mJ -xr-xf BY HWNM Filed Aug.

1969 o. a. MARIS 3,474,843

BLOW-MOLDED CONTAINERS 28. 1967 2 Sheets-Sheet 2 mvzuron DAVID B. MARIS HIS ATTORNEY Kym mm. 4

United States Patent 3,474,843 BLOW-MOLDED CONTAINERS David B. Maris, 19 W. 6th Ave., Scottsdale, Ariz. 85251 Filed Aug. 28, 1967, Ser. No. 663,592 Int. Cl. B65d 53/04, 21/02; B65j 1/04 US. Cl. 150--.5 1 Claim ABSTRACT OF THE DISCLOSURE A relatively large-size, blow-molded plastic shipping and stacking container having a high strength to weight ratio, comprising a body portion having substantially rectangular bottom, side and top portions, closure and opening means in said top portion, said closure means comprising a convex center portion which is adapted to expand outwardly against the inner wall of the container neck when subjected to external pressure, thereby effecting a tight seal. The required pressure is furnished by the weight of a superposed container which is stacked upon the bottom container, the pressure or weight being applied to said expansible convex center portion.

This invention relates to blow-molded containers, and more particularly to such a container having a very high ratio of strength to weight in one piece.

The plastics industry, both raw material producer and end user, have for years had to use a very large double walled container which required a lid, a wooden skid, glue to attach the cardboard to the skid, a plastic bag inside to protect the material from moisture, and steel banding to hold the apparatus together. In addition, the user has to purchase expensive apparatus to tip this very large container to assure that the raw material gathers in one corner thereof for pneumatic or other type of unloading.

Furthermore, the containers prior to this invention, being made of a wettable material, must be warehoused in a dry place to prevent disintegration by the elements and total loss of the product therein, and after use, are generally disposed of as junk, thus representing a loss to raw material producer and end-user.

Such conventional containers weigh from 50 to 55 pounds net weight and must be printed for identification of producer and labeled to identify the contents. Such constructions have proved to be very expensive to the end-user, as its costs must be passed along to the enduser in the price of the material therein contained.

Accordingly, it is an object of this invention to provide a blow-molded one piece container which will eliminate all of the afore-meutioned assembly, glueing, skids, banding, plastic liner bags, printing and labeling.

It is a further object of this invention to provide a container that can be warehoused in the outside weather without damage to container contents.

The present invention provides a container which, being lighter in weight, oflers significant freight savings considering the number of units shipped and as a bonus to the end-user can be reclaimed at his plant and be remolded rather than junked, thus providing vast monetary savings per year.

The present container is so constructed that the tipping apparatus required in the case of the prior art containers will be eliminated.

The present invention provides a blow-molded, one piece plastic container with built-in skids, having a nestable depression in the top to receive the skids of the next container, and having a threaded opening. The threaded opening is beaded to receive a closure, said closure being designed to be screwed onto the opening and being provided with a convex center portion which deforms against the opening wall under the weight of the next stacked ice container, thus providing an interference fit and a positive seal when assembled. Furthermore, the molded container portion and the closure sections have tabs molded into the parting line to provide a tamper-proof seal to be installed at the time of filling. Also, the container has molded-in logo, and label areas, eliminating printing and label attachments.

In accordance with another feature of this invention, the container can be emptied to a predetermined level, which is visible due to the translucency of the container material, and turned on its end to accomplish complete emptying of its contents. Advantageously, the closure is so molded as to have depressions to receive a spanner wrench for positive closing.

In the drawings:

FIGURE 1 is an exploded view of a blow-molded container and closure constituting embodiments of this invention;

FIGURE 2 is a view of several of the containers stacked one on top of the other;

FIGURE 3 is a sectional view of the closure portion illustrating the mechanical and tamper-proof seal;

FIGURES 4A and 4B show sectional cuts of the container in regular and tipped positions, respectively;

FIGURE 5 is a sectional view of the container as molded, showing the line CC which separates the closure from the container.

Referring now to the drawings, there is shown in FIG- URE 5 a sectional view of a blow-molded generally rectangular hollow container 11, having opening and closure portions of different diameters. The body 11 with opening 14 is separated along the line CC into two portions adapted to serve as a container with a threaded opening 14 and a closure or cap 9.

The neck or opening portion 14 has a peripheral shoulder or bead 5 and a threaded portion 6. The closure or cap 12 has threads of a diameter slightly larger than opening threads 6 and both threads have an under cut buttress profile. The cap 9 has a downwardly extending peripheral locking ring or sleeve 7 which provides a receptacle space 10 for peripheral shoulder 5, so that when assembled as shown in FIGURE 3 a substantially permanent interlocking frictional seal is made between opening and closure. Furthermore, the closure has a convex top 9 which when assembled as in FIGURE 3 and when a loaded container 11 is placed on top of said closure as in FIGURE 2, the convex top assumes a flat shape, forcing the inwardly extending locking ring 7 against the inner surface of shoulder 5, thus providing a further frictional fit of the closure with opening 14. In addition to this feature, there are molded into the opening 14 and the closure on lid 12, along the parting line of the molded part, two compression molded tabs 31 and 32 which provide holes to receive a tamper-proof seal.

Referring to FIGURE 1, there is shown an exploded view of the container 11 and closure 12. The bottom of container body 11 has molded-in skids 13 and its top has corresponding nesting depressions 21 in such a manner that there is provided a positive lock-in for recesses 14' which thus perform the sealing of concave closure top 9 shown in detail in FIGURE 3. Upwardly formed sections 15 are provided to receive fork lift or other lifting apparatus for moving the container. On either side of container 11 there are a molded-in logo section 16 and a similar label section 17 for writing directly onto the container.

The closure or lid 12 has provided therein spanner wrench depressions 18 molded therein. Referring now to FIGURE 2, several containers 11 are shown in a stacked position illustrating the efiectiveness of skids 13 fitting into nesting depressons 21 and showing how the recess 14' fit upon and effecting a tight seal as described above.

FIGURE 4A illustrates a container 11 at the end-users facility where raw material is being unloaded by pneumatic or other means 20, such material having assumed a level 19, premarked as a molded-in line 19, (FIG- URE 1).

FIGURE 4B illustrates the container 11 tipped in an on-end position thus concentrating the raw material in an area to be picked up by unloading device 20.

As previously stated, the production of the container and closure of this invention starts with blow molding. The blow-molding process is relatively inexpensive, as it requires a considerably less expensive mold than the injection molding process or other processes. Furthermore, the container must be molded in one piece to have the proper strength, which could not be accomplished by other systems. In addition, the blow molding process can produce various shapes and sizes of containers, however it is most desired to produce the container in sizes most suitable to the plastics industry for packaging polyethylenes, polypropylenes, acrolonitrile-butadiene-styrenes, cellulose acetate bytrates, vinyls and the like. Since the blow molding process is suitable to produce rectangular shapes, shapes such as cubes, cylinders and a number of poly gonal shapes can be produced. Furthermore, the walls of the container can be provided with corrugations, ribbing, fluting, basket weaves or the like.

Of the family of thermoplastics, any blow moldable material may be used for fabricating containers in accordance with this invention. Of the plastics family typical selections would be polyethylene, polyethylene copolymers, polypropylene, polystyrene and mixtures thereof, copolymers of ethylene and propylene, mixtures of polyolefins and polyvinyl halides. However, the material to be used will be dictated in part by the contents that are to be placed in the container.

While the afore-described container is especially suited to pelletized or powdered plastics as raw materials, other materials may be packaged therein such as food stufi's, powdered materials, chemicals, adhesives and the like.

What is claimed is:

1. A blow-molded plastic shipping and stacking container having a high strength to weight ratio, and comprising a body portion having substantially rectangular bottom, side and top portions, closure and opening means in said top portion, said closure means comprising a resilient convex center portion which is adapted to expand outwardly when subjected to external pressure, said bottom portion being formed with a plurality of skid-like leg portions projecting downward from said bottom, said body portion also being formed at the rectangular top end thereof with a plurality of parallel elongated recesses adapted to securely receive and hold said leg portions when said container is stacked one upon another container, a plurality of elongated recesses formed into the base of said container between said leg portions, at least two of said recesses being adapted to receive power lifting means such as fork lift, a central recess formed into the base of said container, said central recess being adapted to receive the closure and opening means of a container upon which it is stacked, the height of said recess being so dimensioned that perpendicular pressure is exerted upon said closure means when one container is stacked upon another container, an annular discharge neck integral with the top portion of said container, said neck being screw-threaded and a peripheral shoulder or head being formed into its discharge end, a closure or cap to fit upon said discharge neck and having threads adapted to fit the threads in said neck portion, a downwardly extending peripheral locking ring or sleeve formed into said closure or cap, said ring being adapted to receive said peripheral shoulder or head, said closure being adapted, when subjected to the weight of a superposed container, to push said locking ring radially outward to a position engaging the inner periphery of the container opening in a manner to form a tight seal therewith.

References Cited UNITED STATES PATENTS D. 201,398 6/1965 Burns 220-97X 1,786,826 12/1930 Cooper 220-39 2,235,617 3/1941 Klinzing 220 39 3,110,411 11/1963 Golde 220 39 3,128,016 4/1964 Ferri 222 143X 3,176,879 4/1965 Mojonner 222-143 3,189,072 6/1965 Starr 150 0.5 3,282,461 11/1966 Beesley 220 21 3,298,415 1/1967 Klygis 150 0.5

40 3,361,290 1/1968 Matthews -0.5X 3,381,845 5/1968 MacDonald 215 44X FOREIGN PATENTS 751,244 8/1933 France.

' GEORGE E. LOWRANCE, Primary Examiner US. Cl. X.R.

Images