US2299281A - Sealing system for container closures - Google Patents

Description

Oct 20, 1942 F. w. SAMPLE SEALING SYSTEMS FOR CONTAINER CLOS'URES Filed Nov. 6, 1957 INVENTOR,

'FLEEK .W. SAMPLE Mz @532W ATTORNEY. v

Patented Oct. 20, 1942 SEALING SYSTEM FORCQNTAIN'E'R CLOSURES Fleck W. Sample, Forest Hills, N. Y., assigner to American Flange & Manufacturing Co., Inc., New York, N. Y., a corporation of Illinois Application November 6, 1937, Serial No. 173,123

7 Claims.

This invention relates to sealing means for container closures and particularly to sealing caps to be used in conjunction with hollow headed plugs.

An object of this invention is to provide sealing means for the closure parts of a container when said closure parts have been attached to said container without provision having been made for -the reception of sealing means.

Another object of the invention is to provide sealing means for closures, which closures have been converted from one type toA another, wherein the origin-a1 type made lno provision for the reception ofsealing means.

Another obj-ect of the invention is to provide sealing means to prevent undetectable tampering with closure plugs lfor containers without any modification of the closure plug being necessary.

Stillanother object of the invention is to provide sealing means to be received within hollow headed plugs toY prevent removal of such plugs without destruction of the sealing means.

A- further object of the invention resides in the provisionof means on sealing caps received in the heads of hollow plugs to prevent removal of-such caps from the plugs without the same being rst mutilated.

A further object of the invention resides in the method of providing sealing means for container closures after the same have been constructed without any provision of means to seal them.

-Other objects of the invention will in part be obvious and will in part appear in connection with the description taken in conjunction with the accompanying drawing.

Closures for metal drums or the like in Atheir earlier forms were not particularly leak-proof and were rather cumbersome and bulky in construction. An example of this is the type where the iiangeor bushing was a heavy pieceof metal welded to the drum stock by spot-welding and the screw plug was formed of cast iron with threads moreor less roughly formed and with a head having a laterally extending flange. Between -that ange and the outer surface of the bushing member a at ring type gasket was received which was intended to prevent leakage or seepage of the contents of the container. Quite -commonly such closure fittings did not prevent such leakage or seepage and since the investment in returnable drums to which Vsuch come necessary to devise means for preventing leakage from such drums.

The instant rinvention not only provides a method Afor converting the previously unsatisfactory closures into closures whose satisfactory functioning is attested to-by their universal adoption, but also provides sealing means which well guard the -converted closures against tampering in spitleof the fact that no provision for sealing was'made in theforiginal fittings. The conversion has been accomplished by accurately countersinking a gasket receiving surface around the mouth of the flange or bushing opening so that when screw plugs of the types set forth in United-States Patents-Nos. 2,040,088, 1,901,196 and 1,982,145, are inserted in the bushing their gaskets will engage the countersunk gasket receiving surface of the bushing and provide a leak-proof closure.

To complete the conversion and prevent unauthorized tampering with the contents of the containers, a seal cap designed to be received within the hollow head of a plug has been devised. This seal cap takes somewhat the form of an inverted `dish having a top which closes the opening yin the hollow plug and a skirt portionv designed to engage the peripheral wall of the 4hollow plug, and projections therefrom, in such a manner as to prevent removal of the cap without destroying the same. As the cap top bridges and closes the hollow head of the plug the same cannot be removed while the cap is intact. Furthermore, as the cap itself cannot be removed and replaced while intact, it can be readily seen that unauthorized tampering Ywithfthe closure will be clearly indicated.

For a fuller understanding of the nature and objects of th'e invention reference should `be had to the following detailed description of the improvements taken in conjunction with the'a'ccompanyingA drawing in which:

Figure 1 is a plan view ofv a closure according to the invention showing part of the bushing member with a plug received therein, which plug issealed by a cap.

Fig. 2 is a sectional elevation on lines 2 2 of Fig. l.

Fig. 3 is a perspective view of the seal cap shown in Fig. 1.

Fig. 4 is a partial plan view of a closure including a different form of screw plug in which isreceived-another form of seal cap.

Fig. 5. is a partial sectional elevation oi the fittings wereapplied is -considerablait has beclosureof Fig. 4.

And Fig. 6 is a perspective view of the form of seal cap shown in F'ig. 4.

In Figs. 1 and 2 there is shown at 5 a portion of a bushing or flange employed as one of the elements of the closure for a drum, container, or the like. This bushing or flange is provided with an opening 6 which is screw threaded for part of its length as shown at 1. The mouth of opening 6 is Countersunk by means of a tool, particularly adapted for the purpose, to provide a gasket engaging surface 8. As surface 8 is notV formed during the formation of the flange and its opening, care must be taken in its later formation to have it concentrically located with respect to the opening and at the proper angle with respect to the axis of the opening, for reasons that will appear hereinafter.

Received in opening 6 and threaded into positions therein as shown in Figs. 1 and 2 is a screw plug 9 of the type shown in United States Patent No. 1,901,196. Plug 9 is provided with a head I of slightly larger diameter than the diameter of its threaded body portion which body portion is provided immediately beneath head I0 with a gasket receiving surface |2 which carries a gasket I3, all as set forth in Patent No. 1,982,145. As is apparent from the showing in Fig. 2, the plug 9 can be screwed down until its head ID enters the mouth formed by gasket receiving seat 8. The extent of this travel of the plug head into the Countersunk seat is predetermined to allow sufficient compression of gasket I3, and is limited by the lower edge I4 of the head engaging the surface 8 to prevent gasket I3 from being subjected to sufficient pressure to destroy it. The inward travel of plug head I9 with respect to the tapered surface 8 is also so chosen that when the plug 9 is screwed home to its proper position, head I9 thereof will project but slightly above the upper surface of bushing or flange 5. The purpose of this latter is to eliminate the chances of the plug when seated in position being contacted and damaged by extraneous objects.

The hollow head I5 of plug 9 has a at bottom surface I6, side wall I'I and inwardly extending lugs I8. Received within said hollow head |5 is a seal cap as shown per se in Fig. 3. This seal cap has a disc-like top I9 and a laterally extending skirt-like portion 29. At diametrically opposed points of disc I9 and continuing down throughout the depth of skirt 29 are formed similar channelled depressions 2| Whose formation is such as to snugly embrace lugs I8 of plug 9. Skirt 29 is dimensioned to snugly embrace the side wall of plug 9 and is of a depth to support disc I9 flush with the top surfaces of lugs I8.

In order to prevent undetected removal of the seal cap, the dimensions of skirt and the side walls 22 and bottom wall 23 of depressions 2| are so chosen that it is necessary to tap the seal cap with a mallet in order to insert it. As is obvious from the relation of skirt 20 and depressions 2I, the action of driving the seal cap into position will set up opposing forces acting to create a binding of the seal cap with respect to the side wall and lugs I8 of plug 9. Since this binding force acts horizontally with respect to the plug and lug walls, and as the head I9 of the seal cap is ush with the top of plug head 9, it is readily apparent that it would be exrather than being directly thereover.

When a drum equipped with closure plugs sealed in this manner reaches its destination, the seal cap can readily be pierced at 25, torn along score lines 24 and removed, whence a wrench can be applied to the plug for removing the same.

In Figs. 4, 5 and 6 there is shown the manner in which a screw plug of the type set forth in United States Patent No. 2,040,088 can be sealed. In this form the engagement of the plug with the fiange or bushing is identical to that shown in Figs. 1-3; the flange or bushing being shown at 35 with an opening at 35 having screw threads 31. Countersunk gasket receiving surface 39 is provided at the mouth of opening 36 and screw plug 39 is shown as provided with a head 40, a threaded body portion 4| and a gasket receiving surface 42 carrying a gasket 43. Here also the lower peripheral edge of the plug head 44 engages the tapered surface 38 in a manner to act as a stop and prevent the destruction of gasket 43.

The hollow head 45 of the plug in this instance differs slightly from that of Figs. 1-3, inasmuch as the means to facilitate removal of the plug is a bar 48 extending diametrically acrossrthe interior thereof and extending upwardly from bottom surface 46, a distance slightly less than the height of side wall 4'| of the plug.

In Fig. 6 there is shown the type of seal cap employed with theY plug of Figs. 4 and 5. This consists of a top in the form of a complete disc 49 and a laterally extending skirt 50 which has a return bent lip 5I at its bottom, the upper end of which lip has an outer engaging surface 52.

VPortions of skirt 59 are removed at opposed sides thereof as shown at 53, providing an opening of such dimension that its sides 54 closely embrace the sides of cross piece 48. Skirt 59 is slightly outwardly bulged intermediate of its extent, as shown at 55, in order to enhance the resiliency thereof.

The seal cap of Fig. 6 is inserted into the hollow head of plug 29 by tapping with a mallet similarly to the seal cap of Fig. 3. In this instance, the disc-like top 43 completely covers the hollow in the head of the plug -as well as covering bar 49. Here again, however, unauthorized removal of the seal cap is prevented by the fact that the top surface of disc 49 lies very slightly below the top surface 49 of the plug head, thereby preventing insertion of a removing tool thereunder. This position of top 49 is due to proper dimensioning of skirt 50 and to the fact that bar 48 has its top surface spaced slightly more than the thickness of disc 49 below the top surface 49of plug 39. As is obvious from the drawing the retaining edge 52 of the returned bent lip 5| engages the side wall 4l of the hollow plug head. A considerable engaging force is present due to the resiliency of the skirt 59 of the seal cap and to the fact that inward collapse of such skirt is substantially prevented by the snug engagement of edges 54 with the sides of bar 48.

|lhe score lines on the cap of Fig. 6 are slightly different from those of Fig. 3 inasmuch as the cross score 55, which is usually the first one punched, must be set oif to one side of bar 48 However, once cross score 58 is broken, tearing along longitudinal score lines 57 can proceed in the usual manner and the seal cap can then be re-` moved and/or destroyed.

Having described my invention and what' I claim as new and desire to secure by Letters Patent is:

1. In structure of the character described, a container wall having an opening therein, an internally-threaded bushing defining said opening, a screw plug threadedly engaged in said bushing and, in its operative position, having its outer face substantially in the plane of the outer surface of the bushing, said plug having the top wall thereof recessed to form a chamber, a toolengaging member extending into said chamber from the wall thereof and lying wholly within the chamber, and a seal cap having a top portion closing the mouth of said chamber and a depending skirt portion formed to frictionally engage the side wall of said chamber to prevent removal of the seal cap without destruction of the same, said skirt portion having its normal contour interrupted to embrace said tool-engaging member and render the same ineffective when the seal cap is in operative position. i

2. In structure of the character described, a container wall having an opening therein, an internally-threaded bushing defining said opening, a screw plug threadedly engaged in said bushing and, in its operative position, having its outer face substantially in the plane of the outer` surface of the bushing, said plug having the top Wall thereof recessed to form a chamber, a toolengaging member extending into said chamber from the Wall thereof and lying wholly within the chamber, and a seal cap having a top portion lying within the mouth of said chamber for closing the same and a depending skirt portion lying along side of and formed to frictionally engage the side wall of said chamber for a substantial portion of the periphery thereof, said skirt portion having its normal contour interrupted to embrace said tool-engaging member and render the same ineffective when the seal cap is in operative position.

3. In structure of the character described, a container wall having an opening therein, an internally-threaded bushing defining said opening, a screw plug threadedly engaged in said bushing and, in its operative position, having its outer face substantially in the plane of the outer surface of the bushing, said plug having the top wall thereof recessed to form a chamber, a toolengaging lug extending into said chamber from the wall thereof and lying wholly within the chamber, and a seal cap having a top portion closing the mouth of said chamber and a depending skirt portion formed to frictionally engage the side wall of said chamber to prevent removal of the seal cap without destruction of the same, said skirt portion being recessed to embrace said toolengaging lug and render the same ineffective when the seal cap is in operative position.

4. In structure of the character described, a container wall having an opening therein, an internally-threaded bushing dening said opening, a screw plug threadedly engaged in said bushing and, in its operative position, having its outer face substantially in the plane of the outer surface of the bushing, said plug having the top wall thereof recessed to form a chamber, and a tool-engaging bar extending across said chamber, lying wholly within the chamber and being secured in place therein, a seal cap having a top portion closing the mouth of said chamber and a depending skirt portion formed to frictionally engage the side wall of said chamber to prevent removal of the seal cap without destruction of the same, said skirt portion having opposed portions thereof removed to embrace said tool-engaging bar whereby said bar is rendered ineffective when the seal cap is in position.

5. A seal cap, for closing the openings in hollow-headed closure plugs and preventing actuation of tool-engaging members extending into such hollow heads, comprising a disc-like closing portion and a peripheral skirt-like retaining portion therearound, said retaining portion extending substantially laterally with respect to said closing portion and having its normal contour interrupted throughout the height thereof for reception of the tool-engaging means of a plug, said closing portion being formed with weakened sections for rendering the seal cap readily destructible.

6. A seal cap, for closing the openings in hollow-headed closure plugs and preventing actuation of tool-engaging lugs extending into the hollow of said heads from the sides thereof, comprising a disc-like closing portion, and a peripheral skirt-like retaining portion therearound, said retaining portion extending substantially laterally with respect to said closing portion, said retaining portion and the adjacent part of said closing portion being inset to form a continuous channel for the reception of said tool-engaging lug and said closing portion being formed with weakened sections for rendering the seal cap readily destructible.

7. A seal cap, for closing the openings in hollow-headed closure plugs and preventing actuation of the tool-engaging bar received within and extending across such hollow heads, comprising a disc-like closing portion and spaced peripheral skirt-like retaining portions extending substantially laterally from the periphery of said closing portion, said retaining portions having reverselyextending retaining lips formed at the free ends thereof, and said retaining portions being spaced apart at opposite sides of said closing portion providing slots for reception of the tool-engaging bar of the closure plug, said closing portion being formed with weakened sections for rendering the seal cap readily destructible.

FLECK W. SAMPLE.

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