US2445465A - Closure plug for containers - Google Patents

Description

y 1948. E. M. AMESBURY EI'AL 2,445,465

CLOSURE PLUG FOR CONTAINERS Filed July 6, 1944 15 10 I7 INVENTORS.

EARL M.AMssauRY, THEODORE W.FRANKS BY 6, JOHN JESEVICH,JR.

ATTORNEY Patented July 20, 1948 CLOSURE PLUG FOR CONTAINERS Earl M. Amesbury, Theodore W. Franks, and John Jesevich, Jr., Chicago, Ill., assignors to American Flange & Manufacturing (30., Inc., New York, N. Y., a corporation of Illinois Application July 6, 1944, Serial No. 543,640

a claims. (Cl. 220-39) This invention relates to closure plugs for containers and particularly to those made complete- 1y out of one piece of sheet metal.

The principal object of the invention is to provide closure plugs for containers from a minimum of material and with minimum effort.

Another object of the invention is to provide a complete closure plug out of one piece of sheet metal, which plug incorporates all of-the features needed to satisfy trade requirements.

Another object of the invention is to provide a complete closure plug formed out of one piece of light weight sheet metal which is strengthened by the forming of the single piece of material.

A further object of the invention is to provide closure plugs for large metal containers, which closure plugs are made out of inexpensive, light weight, material, are useable in standard container openings and are operable with standard wrenching equipment. p

A still further object of the invention is to provide light weight sheet metal plugs with integral, eflective, wrench engaging lugs.

Other and further objects of the invention will in part be obvious and will in part appear as this description progresses andby reference to the accompanying drawing.

With the development of a method and apparatus for forming substantially standard pipe threads in sheet metal, about the weight of the walls of large containers, such as steel barrels and drums, which developments are shown and described in the U. S. patent to Draper No. 2,145,587, some new possibilities opened up in the so called drum closure art. One of these wasthe possibility of using the corners of the square sheets, out of which the round heads for steel barrels and drums are stamped, in the manufacture of closure plugs. Such material had heretofore been considered as scrap.

In the past most plug threads, except those formed by die casting, needed to be out into the metal. This required heavier metal than that obtained as drum scrap or its equivalent weight in new material to assure that the material remaining behind the threads would be at least as thick as that of the container wall stock. Being made of such substantially heavier material, these plugs could easily be provided with a proper gasket seat and efiective wrench engaging means, whether the latter be integral with, or attached to, the plugs. Likewise, the wrench engaging means could be carried within the confines of the plug to enable it to be seated down within an opening and covered by a capseal.

When the attempt was made however, to employ metal of the weight normally encountered in drum scrap, commonly running in the range of 14 to 18 gauge steel sheet, in the making of effective one piece closure plugs, unforseen dimculties cropped up; particularly where the conservation of material and the forming of a flushtype plug were controlling factors. The plug head, if made as a mere extension ofvthe body as in the prior art, and made small enough to seat down flush within an opening, (as shown in U. S. patents to Shera. Nos. 1,982,144 and 1,982,-

), was not strong enough. Its strength was insumcient to prevent the plug and its gasket seat from going out of round from the strains of "wrenching the plug. Furthermore, the head was not strong enough to prevent turning of the plug down into the opening past proper gasketing position. In addition there was nothing rigid enough to carry effective, integral, wrench engaging means; thus a separate, supplemental bar or plate had to be secured to the plug wall in some way, involving separate material and operations. Obviously these defects and additions ofiset any advantages that might be derived from making such a plug out of lighter weight materials than had heretofore been the case.

We have however, devised a plug of the flush type which meets all the requirements of the trade, can be made out of light weight sheet metal and can be made all in one piece with a minimum expenditure of efiort and material. By first forming a cup shaped blank and then simultaneously rolling threadsand swaging a gasket seat into the cylindrical wall of such cup we have been able to cause the metal of the cup to flow towards the free edge of the cup to such an extent as to substantially thicken it. This free edge carries upwardly extending ears to be formed into wrench engaging lugs. These ears are next given a right angle bend inward from a point about midway of their extent and are perforated adjacent their bases, all in one operation. Also, they are bent inward and downward in another operation. 4

The perforation of the ears provides sealing Wire receiving eyelets but serves a more important purpose than that in facilitating the completion of the plug. Since the top of the plug is rim is swaged or coined into its final form, the

perforations in the lugs are somewhat diminished in size. To complete the plug the lugs are further bent into the cup to bring their free ends back into engagement with the inside of the cup wall where it joins the bottom. The bead around such a plug is not a high one and the lugs lie below the top of the head so the plug can be inserted in the common neck type of opening and be covered by a proper capseal. Finally, we have also found that an additional thickening of the stock around the mouth of the plug can be achieved by the swaging or beading operation. This does its part toward strengthening the plug and making it a, commercially successful article.

The plug of the invention is satisfactory from all points of view. It requires no machining operations since the original blank is formed by stamping while the threads and gasket seat are rolled into the metal. The bead is formed by swaging and the lug positioning is completed by swaging and bending. The plug is made from one piece of inexpensive material yet, when finished, it meets all the requirements of the trade.

For a fuller understanding of the nature and objects of the invention reference should be had to the following detailed description taken in connection with the accompanying drawing in which: I

Fig. 1 is a plan view .of a closure plug of the invention.

Fig. 2 is an elevation of the same.

Fig. 3 is a section taken on line 3-3 of Fig. 1 looking in the direction of the arrows.

Fig. 4 is a section taken on line 44 of Fig. 1 looking in the direction of the arrows.

Fig. 5 is a perspective view of the plug looking down into the same.

Fig. 6 is a view partly in elevation and partly in section, showing a closure .plug of the invention secured in place in a container wall opening properly formed to receive it and with a capseal secured in place over the plug and the opening.

Fig. 7 is an enlarged fragmentary section of a portion of the screw threaded wall, gasket seat, and reinforcing bead taken through the center of one of the wrench engaging lugs.

Fig. 8 is a similar view taken at a position I beyond the lug.

Throughout the several views of the drawing the closure plug of the invention is generally indicated by the reference character 10. This closure plug has a bottom wall II, and an upwardly extending side wall l2 whose lower portion is threaded as shown at I3 and whose upper portion is inset as shown at H. The threads of the portion l3 are shown extending both externally and internally with respect to the normal outline of the plug wall. This is due to their having been formed directly out of the stock of that wall by a roller swaging operation such as that disclomd in United States patent to Draper No. 2,145,587. The inset portion M, of the wall l2, provides an exterior seat, or surface, l5, for the reception of a gasket l6. As shown best in Fig. '7, the inset I4 is of sufficient depth that the surface I5 is set back at least as far as the roots of the externally extending threads. In this way the gasket seat is bounded at its lower end by the uppermost thread and, at, its upper end by a laterally extending shoulder H.

The wall I2 terminates in a reinforcing bead or rim l8 overlying the shoulder l1 and materially strengthening the upper end of the plug. This strengthening, as already described results from two steps in the formation of the plug. The first of these is the combination operation of rolling threads and gasket seat simultaneously which causes the metal to flow towards the part to be formed into the head or bead. The second is the additional thickening achieved through the swaging of the stock extending above the surface I1 into beadlike form. This stock is thus not only turned over on itself, inwardly, as shown at I9, but is at the same time given an additional thickness with respect to the first thickening tant of which is the imparting of rigidity to the plug as a whole. In the working of metal as done in forming and threading the plug here, internal stresses are set up which tend to cause distortion. Such distortion, though not necessarily of sufficient extent to prevent adequate threaded engagement of the plug with the opening, nevertheless would be of sufficient extent to impose an uneven pressure upon the gasket l6. In addition, the gasket might be permitted to creep oflf of its seat at certain points in the circumference of that seat. Should either .of these deleterious conditions exist it would be likely to prevent proper closing of the container wall opening. By the thickening of the stock and the forming of the particular bead iii in the manner described however such distortion is substantially eliminated.

Another important function performed by the strengthened portion I8 is the carrying of the wrench engaging lugs 20 which extend inwardly and downwardly at 2| as an integral continuation of the inwardly turned portion I9 01' the bead l8. These lugs extend into the hollow head of the plug a suflicient distance to enable their engagement by a simple wrench, bar, or the like and then are turned inwardly and downwardly from their innermost extension 22 into substantial engagement with the interior of the threaded wall at their termination at 23. Without a thickened and reinforced bead to support and stiffen them, these lugs would readily collapse or tear when engaged by the normal type of wrench or tool employed in this art. With the bead acting as it does however, and with the lugs turned inwardly at their bottoms to engage the threaded wall, it has been found that they resist collapse and tearing to a marked extent. Thus the necessity of employing an additional part or parts secured to the plug to provide wrench engaging means is obviated.

Though this plug, as best shown in Fig. 6, is of the flush-type, i. e., it seats down within the opening to which it is applied so that a capseal may be secured over it, there may be times when it is desirable to seal it in place by means of a lead and wire seal. As already pointed out, the perforation of lugs 20, to enable the material of the lugs to flow thereinto while the plug head and base of the lugs are being beaded over, is

most useful in eliminating distortion. These perforations should, however, be large enough so that after the lugs are fully formed perforations 24 are still large enough to enable a sealing wire to be passed therethrough. Such wire, in accordance with common practice, would be anchored by means of the usual lug or eyelet carried on the container wall.

The plug of this invention thus furnishes the solution to all the problems which have heretofore prevented the use of light weight sheet metal with swaged threads in the formation of economical flush-type plugs. The strengthened, swaged bead around the head of the plug adequately strengthens it against distortion due to strains imposed upon it in the applying or removing of it. The complete plug is, nevertheless, all made out of one piece of material, so has the advantage of economy of material and economy of forming operations, without sacrificing any of the requirements of the trade for an effective plug.

In Fig. '7 there is shown a section taken through the middle of one of the wrench engaging lugs. From this showing it is apparent that the lug does not materially interfere with the forming of a uniform bead and gasket seat. Such would not be true however, were the perforations 24 not made of substantial size at the outset to permit the flow of metal into them. Instead a considerably distorted bead would result.

It is believed that changes and modifications could be made in the article above described without departing from the scope of the invention and it is accordingly intended that the description and drawing are to be interpreted merel as illustrative of the invention and not in a limiting sense.

Having described our invention, what we claim is new and desire to secure by Letters Patent is:

1. An integral one-piece sheet metal plug for containers, comprising, a bottom portion, a side wall extending up therearound, said wall being provided with screw threads throughout a portion of its height, a reinforcing bead around the free end of said wall, said bead being formed by extending the stock of said wall outwardly and then turning it inwardly toterminate substantially in line with said side wall and a tool engaging lug extending from the terminating edge of the inturned portion to a point spaced from said 6 wardly from the inturned edge of said bead and then reversed outwardly and downwardly to terminate in engagement with the interior of said wall.

4. An integral one-piece sheet metal plug for containers, comprising, a bottom portion, a side wall extending up therearound in substantially cylindrical form and a, re-inforcing bead around the open free end of said cylindrical wall, said bead being formed by extending the stock of said wall outwardly and then turning it inwardly to terminate in a free edge and a tool engaging member extending from said free edge inwardly of said plug and away from said adjacent side wall, said tool engaging member extending a substantial distance away from the adjacent portion of said side wall and engaging the same again at a position spaced from its commencement.

5. An integral'one-piece sheet metal plug for containers, comprising, a bottom portion, a side wall extending up therearound in substantially member extending, from said free edge inwardly of said plug and away from said adjacent. side wall, said tool engaging member extending downwardly throughout substantially the entire height of said side wall and having a portion extending inwardly a substantial distance away from the opposed portion of said side wall.

6. An integral sheet metal closure plug for containers, comprising, a bottom portion, a side wall extending up therearound in substantially cylindrical form and a re-iniorcing bead around the open free end of said cylindrical wall, said bead being formed by extending the stock of said wall then turned backwardly to terminate in substantial engagement with said wall.

2. In an integral one-piece sheet metal closure plug, the combination of a side wall formed with roller swaged internally and externally extending wall outwardly and then turning it inwardly to terminate in a free edge and a tool engaging member extending throughout substantially the entire height of said side wall, the upper end of said member extending into said free edge at spaced positions and said tool engaging member having an intermediate portion extending a substantlal distance inwardly of said plug away substantially standard pipe threads, a returned bent, thickened, reinforcing bead formed around the end of said screw threaded wall and a wrench engaging lug extending integrally from said bead away from said wall and returned into engagement with said wall at a point spaced from said bead.

3. An integral one-piece flush type sheet metal closure plug for containers, comprising, a bottom disc-like portion, an annular side wall extending up around said disc-like portion and being provided, throughout a portion of its height with roller swaged substantiall standard pipe threads, the stock of said wall above said threads being inset with respect to the threaded portion to form a gasket receiving seat and the stock of said wall at the upper end of said gasket seat being formed outwardly and turned inwardly in the form of a bead, the portion of said stock comprising said bead being substantially thicker than the adjacent stock to reinforce the open tending inwardly of and within the confines of said wall, said lugs extending inwardly and downend end of said plug, and tool engaging lugs exfrom said side wall.

EARL M. AMESBURY. THEODORE W. FRANKS. JOHN-JESEVICH, JR.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 640,121 Foreman Dec. 26, 1899 874,256 Sleight Dec; 17, 1907 1,431,911 Jones Oct. 10, 1922 1,737,605 Mauser Dec. 3, 1929 1,792,622 Wikstrom Feb. 17, 1931 1,838,285 Rieke Dec. 29, 1931 2,254,005 Dodson Aug. 28, 1941 2,337,456 Draper Dec. 21, 1943 FOREIGN PATENTS Number Country Date 177,084 Switzerland Aug. 1, 1935 642,732 France May 6, 192B

Images