US3529751A - Method of constructing containers and product thereof - Google Patents

Description

P 1970 P. A. MARCHANT 3,529,751

METHOD OF CONSTRUC IING' CONTAINERS AND PRODUCT THEREOF Filed Aug. 4, 1967 2 Sheets-Sheet 1 fiaxgo United States Patent US. Cl. 222-92 1 Claim ABSTRACT OF THE DISCLOSURE A container having a hollow body provided with an end wall in which an opening extends therethrough; a neck structure disposed in said opening; said end wall compressed inwardly toward said opening and indented into the perimeter of said neck structure to secure the neck structure axially and to resist rotation relative to the container body; the invention also comprising a method for inserting said neck structure into said opening in said end wall and compressing the end wall inwardly so as to cause structure surrounding said opening in the end wall to become indented into the perimeter of the neck structure.

This invention relates to a container and more particularly to a container in which the body of the container and the neck thereof are of dissimilar materials.

BACKGROUND OF THE INVENTION In the fabrication of containers and particularly collapsible containers for containing material such as fluoride toothpaste or the like, it has been found desirable to employ dissimilar materials for the container body, and the neck structure of the container; such construction has been used in prior art containers and particularly toothpaste tubes or the like in which the hollow bodies thereof are made of thin metal.

Fluoride toothpaste, when exposed to the atmosphere on the threaded neck portions of conventional metal tubes, creates an undesirable dark coloring. Such a condition has been objectionable and various attempts have been made to produce suitable containers having collapsible metallic bodies with plastic neck structures to avoid the foregoing undesirable affect of the fluoride materials on the thread portions or outer areas of the container neck.

It has been a problem properly to seal plastic outlet neck structures in connection with collapsible metallic container bodies such as a toothpaste tube or the like. Furthermore, it has been a problem to provide suitable structure to resist torque and relative rotation between the neck and body of the container or tube during operation of a closure such as a screw threaded cap normally utilized on toothpaste tubes or the like.

Considerable torque resistance must be afforded by the connection of the container neck relative to the body thereof. Additionally, very efficient seals must be provided in the connection between the neck and the body of the container so as to prevent the escape of volatile solvents or fluids such as toluene, acetone and benzine, or the like, from contents such as cement or other materials which include such highly volatile solvents.

Heretofore, various dissimilar materials have been used for the production of the bodies and necks of collapsible container structures, however many of the necks of such containers have either been screw threaded externally onto internal metal necks of collapsible tubes, or the dissimilar necks have been inserted through an opening in the end wall of the container body from the inside. In such a fabrication procedure, the neck structure of the container must be inserted through the open end of the container body a considerable distance to the opposite partially closed end wall and through an opening therein and must then be fastened in the end wall to project outwardly therefrom.

This mode of inserting a neck of dissimilar material into a collapsible metal tubular body is considerably un wieldly. This is especially notable relative to high volume production of collapsible containers such as toothpaste tubes, or the like.

Additionally, such a procedure of inserting a neck of dissimilar material into a collapsible metallic tube poses both of the foregoing problems of suitably sealing the neck in the end wall of the metallic tube and also securing the neck structure against axial or rotational movement relative to the tube body.

All of the foregoing considerations mitigate against ultimate economy in the production of such containers with the neck structures of dissimilar materials, particularly when said neck structure must be inserted through the end wall of the container body from the inside toward the outside thereof.

SUMMARY OF THE INVENTION The container of the present invention comprises a hollow collapsible body preferably made of thin metal and having an end wall provided with an opening therethrough, in which a hollow neck structure of dissimilar material is secured against axial and rotational displacement and the structure of the invention also provides a very eflicient seal between the body and the neck structure thereof.

The end wall of the thin metal body is substantially thicker than the side walls thereof and is initially formed into an outwardly directed frusto-conical shape with an opening therein. The plastic neck structure is inserted in the opening from the outside toward the inside, and the frusto-conical end wall is displaced from a frustoconical shape to a substantially flat shape when forced in a direction toward the inside of the tube.

During this deflection the perimeter of the end Wall is restrained by a suitable die so that compression of the end wall, when being formed from a frusto-conical shape to a substantially fiat shape, tends to reduce the size of the opening in which the neck structure is inserted. Thus, the structure surrounding the opening in the end wall is caused to become indented into the perimeter of the neck structure to create an efficient seal and to lock the neck structure in the end wall against rotational movement as well as axial displacement therefrom.

The neck structure and the end wall of the tubular body are thus so arranged that the neck structure may be readily and rapidly inserted from the outside of the container body into an opening in the end wall thereof to facilitate the assembly of the container as well as to facilitate operation of the tooling required to make the assembly of the container body and the neck structure.

Accordingly, it is an object of the present invention to provide a hollow container body having an end wall provided with an opening therein and a hollow neck structure having its perimeter portion disposed in said opening and held under compression by the structure surrounding said opening, such that said surrounding structure is indented into the perimeter of the neck structure to provide an efficient seal between the end wall of the container and the neck structure and also to resist rotational or axial movement of the neck structure relative to the container body.

Another object of the present invention is to provide a novel method for producing a container such as the collapsible toothpaste tube, or the like, wherein a hollow container body is initially a substantially frusto-conical end wall having an opening therein whereby, the perimeter of the neck structure may be inserted into said opening whereupon deformation of said frusto-conical structure to a fiat structure and deflection thereof toward the interior of the tube causes compression of the end wall radially inward to reduce the size of the opening and to cause the structure surrounding the opening to become indented into the perimeter of the neck structure.

Another object of the invention is to provide a novel method for securing a neck structure in collapsible hollow metallic container body wherein a frusto-conical end wall of the container body is formed with an opening substantially centrally therein whereby a neck structure of dissimilar material is inserted in said opening and the frusto-conical end wall is deflected toward the interior of the container while the perimeter thereof is restrained such that the opening in the end wall is reduced in diameter to cause the structure surrounding the opening to become indented into the perimeter of the neck structure.

Another object of the invention is to provide a container of the collapsible type having a neck structure of dissimilar material relative to the material of the container body and wherein the connection of the neck structure with the body structure is very simple and economical and conducive to high production of such containers at a minimum cost.

[Further objects and advantages of the invention may be apparent from the following specification, appended claims and accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an axial sectional view of a pair of container assembly dies showing a container neck structure of the invention and a container body of the invention in the dies and in position to be assembled;

FIG. 2 is another view similar to FIG. 1 and showing a progression of the assembly of the neck and body structures of the invention in a position wherein the perimeter of the neck structure is initially inserted through an opening in a frusto-conical end wall of the container body of the invention;

FIG. 3 is a further view similar to FIGS. 1 and 2 and showing a respective successive step in the assembly of the container neck and body structures of the invention and showing the complete assembly thereof with the container body and neck remaining in the assembly dies;

FIG. 4 is an enlarged fragmentary sectional view taken from the line 44 of FIG. 3; and

FIG. 5 is an enlarged fragmentary sectional view taken on substantially the same plane as FIG. 3 and showing details of the structure surrounding the opening in the end wall in the container body compressively indented into the perimeter of the neck structure of the container of the invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS As shown in FIG. 1 of the drawings, a container body in accordance with the present invention comprises a thin hollow cylindrical tubular portion 12 and an end wall portion 14. These portions are integral and preferably made of soft metal or the like such that the hollow tubular body 12 may be collapsed to eject the contents of the container toward the end wall 14. The container body 10 is thus similar to conventional collapsible containers such as toothpaste tubes or the like.

The end wall 14 is generally frusto-conical and converging outwardly in the direction of an arrow A in FIG. 1 of the drawings, away from the interior 16 of the container body 10.

The end wall 14 is provided with an opening 18 adapted to receive a hollow neck structure 20 which is made of material dissimilar to the collapsible metal body 10. The neck 20 is preferably made of plastic or other material which does not react to the corrosive eifects of fluoride or 4 the reactionary effects of the fluoride material and toothpaste or the like.

The opening 18 in the end wall 14 is surrounded by the structural edge 22 which may be serrated as shown in FIG. 4 of the drawings; the serrations serving as anti-rotational locking means and being designated 24. These serrations 24 are indented into a perimeter portion 26 of the neck structure 20 and are thus disposed in an axial shear relation to the perimeter portion 26.

The neck structure 20 is provided with a cap retaining neck portion 28 having external screw threads 30 adapted to be engaged by conventional toothpaste tube caps or similar caps, adapted-to retain the contents in the neck structure and the tubular body 10. The neck structure is provided with a materials dispensing passage 21 extending therethrough.

In accordance with a method for assembling the neck structure 20 in the body 10 a die 32 is provided with a bore 34 conforming with a substantially frusto-conical shoulder 36 of the neck structure 20. Additionally, the die 32 is provided with an enlarged slightly conical bore portion 38 adapted to engage a perimeter portion 40 of the end wall 14 of the container body 10 for restraining it radially during a deflection and deformation of the end wall 14 from a frusto-conical form to a substantially flat disposition at right angles to the longitudinal axis of the body 11 as will be hereinafter described in detail.

The die 32 as shown in FIG. 1 retains the neck structure 20 in the bore portion 34 and another die 42 is engaged in an internal bore 44 of the container body portion 12. This die 42 is provided with an end portion 46 disposed substantially at right angles to the longitudinal axis of the die 42 and the hollow tubular body portion 12. The end portion 46 is adapted to form an abutment or stop to locate the final angular disposition of the end wall 14 of the container body of the invention when the neck structure 20 is assembled in the opening 18 of the end wall 14.

As shown in FIG. 2 of the drawings, the dies 32 and 42 are in a position wherein the perimeter portion 26 of the neck 20 is disposed in the opening 18 of the end wall 14 of the container body 10. In this position the perimeter portion 26 is surrounded by the serrated structure 24. As the dies 32 and 42 are forced together the tapered bore portion 38 of the die 32 restrains the periphery 40 of the frusto-conical end wall 14 from moving radially outward such that deformation of the frusto-conical end wall 14 into the position shown in FIG. 3 causes inward compression of the end wall 14 to reduce the diameter of the opening 18. The dies thus force the serrated structure 24, surrounding the opening 18, into the perimeter 26 of the neck structure 20. This causes the structure 24 to become indented into the perimeter 26 as shown in detail and on a large scale in FIG. 5 of the drawings. In FIG. 5 the structure is shown in final assembled position with the structure of the end wall 1 4, surrounding the opening 18,

indented into the perimeter 26 of the neck structure 20.

Accordingly, the opening 18 constitutes a serrated bore which is frusto-conical and converging toward the outer side 62 of the end wall 14.

As shown in FIG. 5, the original disposition of the perimeter 26 is indicated by a broken line 48 which aligns with a dimension line 50. The indented disposition of part of the perimeter 26 is indicated by another dimension line 52 and the total dimension of radial indentation, of the perimeter 26 by the structure 24, is indicated at 54.

The original frusto-conical disposition of the end wall 14 is indicated by broken lines 56 in FIG. 5 and it will therefore be appreciated that the perimeter portion 26 is only slightly smaller initially than the opening 18, such that the perimeter portion may readily be inserted into the opening 18.

To facilitate such insertion the neck portion is provided with a frusto-conical extension 56 which projects axially beyond the perimeter portion 26. This frustoconical portion converges inwardly towards the interior of the container body and, as indicated in FIGS. 1 and 2 of the drawings, said last mentioned frusto-conical portion aligns with the opening 18 when the parts are assembled by the dies 32 and 42. Thus an end portion 58 of the frusto-conical tapered portion 56 is smaller than the opening 18 in the end wall 14 readily to align and facilitate insertion of the perimeter portion 26 into the opening 18.

Adjacent to perimeter portion 26 is an enlarged diameter shoulder portion 60 which extends radially beyond the bounds of the opening 18 and beyond the perimeter portion 26 and forms a shoulder abutment which is brought to bear upon an outer side 62 of the end wall 14 when the neck and body structures are assembled as shown in FIGS. 3 and 5 of the drawings.

It will be seen from FIGS. 3 and 5 of the drawings that the opening 18 is finally reduced in diameter such that the serrated structure 24 assumes a substantially frusto-conical form converging outwardly toward the outer side of the end wall 14. Thus the indented frustoconical assembly of the serrations 24 provides an interference abutment represented by the dimension 54 in a complete annular disposition around the perimeter portion 26. This frusto-conical interference of the indented structure provides for resistance to the displacement of the neck structure 20 from the container body in a direction of an arrow C in FIG. 5 of the drawings. The serrated structure 24 indented into the perimeter portion 26 also provides for torque resistance to the rotational displacement of the neck structure 20 about the axis of the thread 30. When the neck structure and container body are assembled as shown in FIG. 5 of the drawings, normal operation of a toothpaste tube cap relative to the threads 30 will not loosen or disengage the neck structure from the container body end wall 14.

Additionally, it will be appreciated that the indentation of the structure of the end wall, surrounding the opening 18, into the perimeter 26 of the plastic neck structure creates a very efficient and intimate seal to prevent the leakage of fluids even the most volatile fluids such as toluene, acetone and benzine or the like.

It will be appreciated that according to the method of the invention, the restraint of the peripheral portion 40 of the end wall 14 of the body is important during the compression forming of the end wall 14, to cause indentation of the structure surrounding the opening 18 into the perimeter portion 26 of the neck structure 20. It will be seen that the axially tapered bore portion 38 is somewhat frusto-conical and when the dies 32 and 42 are moved together this tapered portion 38 tends to force the perimeter 40 of the end wall 14 inwardly to compression form the end wall 14 radially inward and to reduce the diameter of the opening 18.

It will be appreciated by those skilled in the art that this is a relative operation either by way of restraining the perimeter 40 or by way of actually radially compressing the end Wall 14 in the dies 32 and 42. As shown in the drawings, the periphery of the end wall 14 is merely restrained while deformation of the frusto-conical end wall 14 geometrically causes compression of the structure such as to reduce the diameter of the opening 18 and cause indentation of the serrated structure 24 into the perimeter portion 26 as herein before described.

It will further be appreciated by those skilled in the art that the forming of the end wall 14 from a frustoconical shape into a shape substantially flat, at right angles to the axis of the container body 10, is a very simple and eflicient forming method operating somewhat on the toggle principle such that leverage is great in relation to the acute angle of the frusto-conical structure. Thus a very smooth and efficient forming operation occurs to attain a reduction of the diameter of the opening 18 and the indentation of the structure surrounding the opening, into the perimeter portion 26 of the relatively soft plastic neck structure 20.

It will further be appreciated that the material of the container body is relatively harder and of a greater compressive strength than the material of the neck structure 20, this being of plastic while the container body is preferably made of soft metal and thus the perimeter portion 26 of the neck structure tends to flow into conformance with the structure surrounding the opening 18 and the end wall 14.

It will be obvious to those skilled in the art that various modifications of the present invention may be resorted to in a manner limited only by just interpretation of the following claim.

I claim:

1. In a container body and neck structure, the combination of: a hollow container body of a collapsible metallic material being sufiiciently thin to permit collapse of the Walls thereof by human hand pressure and having an integral end wall; said end wall having an opening extending therethrough and being substantially thicker than the side walls thereof, said opening being bounded by a serrated edge, a materials dispensing neck structure formed of plastic material, said neck structure bearing a cap retaining neck portion provided with screw threads that are adapted to be engaged by a threaded cap m mber, said neck structure including a perimeter portion that is normally slightly larger than the opening in said end wall of said container body and further having a frustoconical aligning portion extending downwardly from said perimeter portion; said perimeter portion held under compression in said opening in said wall of said container body; a radially extending frustoconical shoulder portion of said neck structure above said perimeter portion overlying the top wall of said container in face-to-face relationship therewith, said serrated edge surrounding and being indented into the perimeter portion of said neck structure, said compression and said face-to-face relationship being sutficient to prevent said neck structure from rotating when a cap is threaded and tightened on said neck portion and further being sufficient to seal against leakage of fluids contained in the container.

References Cited UNITED STATES PATENTS 2,352,384 6/1944 Hoch 222-92 2,374,796 5/1945 Amberg 222l07 2,386,498 10/ 1945 Ostrander 222l07 3,231,156 1/1966 Schultz 222-92 2,727,659 12/1955 Nyden 222566 X 2,813,664 11/1957 Punte 222566 2,815,894 12/1957 Henchert 222566 ROBERT B. REEVES, Primary Examiner F. R. HANDREN, Assistant Examiner US. Cl. X.R.

UNITED STATES PATENT OFFICE 569 CERTIFICATE OF CORRECTION Patent NO- 3.529.751 Dated sggtembfl 22 1920 Inventor-(s) Paul A. Marchant It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

REXALL DRUG AND CHEMICAL COMPANY should read:

DART INDUSTRIES INC.

3mm W13 saauzn M26871 WHJIIIM E- SUW. JR- C-omissioner of lhtents

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