US2254005A - Closure device for container openings - Google Patents

Description

Aug. 26, 1.941,

Filed July 14, 195

4 V I, fl I X INVENTOR.

/ HwqpdZM fiaisorz BY T gfyC- C E A ORNEY.

Patented Aug. 26, 1941 Howard W. Dodson, Philadelphia, l"a., asslg'nor, by mesne assignments, to United Steel Barrel Company, Philadelphia, Pa., a corporation of Pennsylvania Application July 14, 1939,: Serial No. 284,463

4 Claims.

The present invention relates to closure devices for openings in metal containers, such as drums, barrels, cans, tanks, or the like, and particularly for openings through which such containers,

drums, barrels, cans, tanks, etc. may be filled which the invention consists can be variously arranged and organized and that the invention is not limited to the precise arrangement and organization of the instrumentalities as herein and emptied. The present invention relates more particularly to container openings and closure devices therefor which are to be repeatedly opened and closed.

The'cost of production of closure devices for container openings islfrequently a vital factor bearing upon the practicability of the devices,

particularly where the containers, such as the sheet-metal drums, barrels, cans, tanks, or the like are likely to be used only once for the transportation or storage of the original contents and it is therefore important to provide not only effective closure means having suflicient structural strength, but also closure means which an be produced at low cost, and which can be m de uniform by manufacturing operations not subject to failure. Since such closure devices must be made in large quantities, it is important that the construction shall be one which will be dependable in mass production.

Among the objects of the present invention is the provision of strong and durable closure means for sheet-metal containers, such as drums, barrels, cans, tanks, etc. which ,will be dependable and which may be produced at low cost, and in which the possibilities of failure, either in the manufacture or in the use thereoL-are minimized.

of the container.

shown and described.

lngthe accompanying drawing, wherein like reference characters indicate. like parts,

Figure 1 represents a fragmentary view, partly in section and partly in elevation, of a drum head opening and closure means therefor constituting one embodiment of the present invention.

Figure 2 represents a bottom plan view of said drum head opening and associated closure means, as would be-seen for instance on line 22 of Figure 1 looking in the direction of the arrows.

Figure 3 represents a perspective view, on a somewhat reduced scale, of the removable screwthreaded closure plug shown in Figure 1 disassociated from the rest of the device.

According to the present invention, a hole or opening,,indicated generally by the numeral I0, isformeddn the sheet-metal of the head or body Inthe particular illustration shown, the body sheet-metal or body metal H is indicated as being that of the head or generally flat end of a sheet-metal container, such as a With the above and other objects inview'which will appear more fully from the following detailed description, accompanying drawing. and

appended claims, the present invention contemplates an outwardly-projecting flange at the opening. of a sheet-metal container, said flange being formed integrally with the body metal of the container and externally reinforced by a fixed; cast band enveloping said flange, said remforcing band being cast in situ in a molten state'from a metal separate and distinct and different'from the body metal of the container.

The present invention furtherconsists of other I novel features and principles and details of construction, all of which will appear more fully from the following detailed description, elccompanying drawing and appended claims. 7

For the purpose of illustrating the invention, there is shown in the accompanying drawing one form thereof which is at present preferred, since the same ,has been found in practice to give satisfactory and reliable results, although it is to-be understood that various instrumentalities of 55 the container. Thus, in accordance with the barrel, can, tank, etc.,'although it is to be expressly, understood that the present invention is equally applicable to openings formed in the more or less cylindrical sides of such containers.

The body metal at. the zone of the opening is l stan ped or pressed outwardly to form a generally .cyl drical outwardly-extending neck or flange l2, d in the illustrated embodiment of the present inventidn the outerl marginal portion of this neck It is turned down to provide a peripheral gasket-seating end-flange ii.

A screwthread of any desired pitch and outline, as for instance, the coarse rounded screwthread It illustrated in the drawing, may be,

rolled, turned, pressed or otherwise formed along the side of, the cylindrical flange l2, thereby'to provide securement cans for a correspondi'nglythreaded closure plEE l5. If desired, the-pitch of the thread It may assume a form other thanthe curved form illustrated.- Thus, tlre fnumber of threads per inch may be increased or decreased making the thread i4 finer or coarser; and the shape thereof may assume a sharp V-shaped or other forms.

This screw-threaded flange I 2 is snugly encircled by a reinforcing band or shell 16 which is cast in situ from molten metal separate and distinct and different from the body metal' of varied, and the thread may present invention, a mold having a concavity or a metal-receiving space corresponding in size to the desired cross-section of the ultimate reinforcing band is applied over the outwardly-extending screw-flange l2, with the flange acting as a core within said mold.

The particular construction of themold and the manner of its application to the container screw-flange is not shown here, because this specification is intended to be addressed to the resultant product and the method of making the same, and not to the apparatus for practicing the method or making [the product.

A relatively low melting point alloy, consisting principally of zinc, with variable amounts of aluminum, copper and magnesium, and, optionally, with some percentages of tin and antimony is then poured or forced into the mold under pressure in a molten state, and at a temperature sufficiently high to insure that the metal alloy will flow freely and will completely fill .all the unoccupied space in said mold.

A suitable low melting point alloy composition for the flange-encircling band It 'may be repre sented by a composition of ninety to ninety-five per cent zinc and about five per cent aluminum, one to four per cent copper and about .01 to .05

' per cent magnesium. These proportions may be varied according to the degree of hardness and other qualities desired.

As the molten metal hardens around'the screwflange l2, it becomes fixed relative thereto, and

the casting I6 is prevented from being rotated 1 thereon, or moved axially therealong. Thus, since the cast reinforcing band l6 closely follows the external contour of the screw-thread |l along the side of the screw-flange l2, and since the band I6 is further axially confined between the juxtaposed end-flange I3 and the body metal H at the base of the screw-flange, rotary and/or axial movement of this band is prevented.

Prior to the application of the molten metal to form the flange-reinforcing band 5, the body metal, at least in the zone of the application of the molten metal, is preferably cleaned of all scale. In this manner, substantial adhesion or union or metal-to-metal bonding may be obtained between the molten metal and the body metal. This union or bonding may be further "augmented or increased by initially turning orcoating or platingthe bodymetal with cadmiumor zinc in. the zone where the molten metal is to be applied.

If desired, any suitable additional means may be provided for further preventing or restraining the flange-reinforcing band or shell Hi from rotating or becoming loosened on the screwflange l2. Thus, for example, anti-rotational surface irregularities may be formed in the container body metal surrounding the base of the screw-flange 12. Thus, an annular zone of the body metal disposed at the'base of the screwflange l2, may be pressed, stamped or otherwise shaped into corrugated or undulating form, to.

provide radially extending alternate ridges I1 and troughs l8. As the molten metal from which the reinforcing band I6 is cast is forced into the molding, it enters into and fills the troughs l8 and accordingly when the casting l6 subsequently hardens it will be further restrained from rotating on the neck |2.

The container wall around the screw-flange |2 may be structurally strengthened, if desired, by an annular ridge or raised portion I! which may be provided by slightly off-setting the annular zone at the base of the flange I2 outwardly or inwardly relative to the contalnerwall II.

In the illustrated embodiment of the present invention the reinforcing band, I6 is cast with a generally fiat annular end-surface 20 disposed in the same plane as the gasket-seating surface of the end-flange l3 and indeed in direct continuation thereof, thereby providing a relatively wide smooth and uninterrupted gasket-seating surface. A sealing gasket 2| is pressed down onto the seating surfaces l3 and 20 by the closureplug l5, which is itself provided with an annular gasket-seating surface 22 in juxtaposition with the screw-flange end-surface l3. 'In use, the sealing gasket 2| is operatively compressed as the screw-plug I5 is screwed into the screwflange l2. 1

By providing a gasket-seat onthe body metal comprising the end-flange lit, the fluid-tight seal established when the gasket 2| is pressed down thereover will not be affected by any possible cracking or fracture of the die-cast flangeencircling band It. Thus, for instance, the cast band l6 may become fractured or cracked anywhere along its periphery, and may even be completely broken through at one or more points, without affecting the seal established by the gasket 2|, because the gasket is pressed directly against the continuous and uninterrupted body metal surface IS.

The screw-threaded closure plug I5 may be inexpensively constructed by being stamped or .pressed out of blanks of suitable sheet-metal,

preferably of heavier gauge than the container body metal. The particular closure-plug illustralted in the drawingis of hollow construction, and is provided at its upper end with polygonal seizure-means 23 adapted to be seized or engaged and turned by any suitable wrench or tool, thereby to tighten or loosen said plug.

After the plug l5 has been screw-threadedly engaged withthescrew-fiange l2 and tightened, a tamper-indicating sheet-metal sealing cap 24 may be superimposed over the plug with its peripheral edge portion 25 crimped or turned under the band shoulder 26, so as completely to prevent access to the plug it during transportation or storage of the container. In removing the tamper-indicating sealing cap 24, the crimped-flange 25 thereof is, so distorted as to 'make reapplication' of the Y sealing cap impossible without detection.

ing,. and the thread bearing portion of the body metal is structurally reinforced by the encircling band cast in situ. Accordingly, the closure device of the present invention possesses structural strength and durability far in excess of that ohtainable from the mere use. of a screw-flange formed directly out of the container sheet-metal,

particularly where the container sheet metal is relatively thin, as is frequently the case. Thus, the hereinabove described construction provides strong and efiective container. closure means which directly utilizes the body metal of the container to anchor the removable plug, and which does not depend on separate thread-bearing flanges or bushings for structural strength and which'is yet very strong and durable even when the particular sheet-metal from which the container is formed is relatively thin.

The present invention may be embodied in other specific forms without departing from the spirit or essential attributes thereof, and it is therefore desired that the present embodiment be considered in all respects as illustrative and not restrictive, reference being had to the appended claims rather than to the foregoing description to indicate the scope of the invention.

Having thus described the invention, what is hereby claimed as new and desired to be secured by Letters Patent, is:

1. In a sheet metal container of the character described, a sheet metal panel having an opening' therein bounded by an integral outwardly extending generally cylindrical annular flange,

the longitudinal axis of said flange being generally perpendicular to the plane of said panel at the base of the flange, the wall'of said flange being helically corrugated and having its inner surface adapted for direct screw-threadeden- V gagement with the threaded outer surface of .a

closure plug, the outer end portion of said flange being turned downwardly into juxtaposition with the panel metal surrounding the basal portion of said flange, and a relatively thick annular flangereinforcing band of a lower melting point metal, cast in situ, extending around solely the outer surface of said flange and reaching from the and snugly filling the troughs or said corrugationsQwhereby said cast band is non-rotatable panel metal at the base of said flange to the juxtaposed downturned outer end portion of said flange, the metal of said cast band extending into and snugly fllling the troughs of said helical corrugations in the flange wall, whereby said cast band is non-rotatable relative to said flange and snugly backs said flange in a zone generally coextensive with its zone of screw-threaded engagement with said closure plug therebymaterially relative to said flange and snugly backs said flange in a zone generally coextensive with the zone of engagement between said flange and said closure plug thereby materially strengthening said flange around said zone, said cast band being generally confined to the immediate vicinity of the panel opening, but not extending thereinto.

3. In a sheet metal container of the character described, a sheet metalv panel having an opening therein'bounded by an integral outwardly extending generally cylindrical annular flange, the outer end portion of said flange being turned downwardly to provide a generally flat annular surface, and an annular flange-reinforcing band,-

cast in situ of a lower melting point metal, encircling said flange, said cast band including a generally flatannular end surface co-planar with andin direct continuation of the aforesaid annustrengthening said flange around said zone, said 7 cast band being generally confined to the immediate vicinity of the panel opening, but not extending thereinto.

2. In a sheet metal container of the character described, asheet metal panel having an opening therein bounded by an integral outwardly extending generally cylindrical annular flange, the iongitudinal axis of said flange being generally perpendicular to the plane of said panel at the base of said flange, the inner surface of said annular flange being adapted for intimate direct engagement with the outer surface of a closureplug adapted to receive a sealing gasket.

lar surface, said co-planarannular surfaces compositely'providing-a generally flat gasket seat 4. In a sheet metal container of the character described, "a metal panel having an openingtherein bounded by an outwardly extending generally cylindricalflange having its longitudinal axis generally perpendicular to the plane 'of the panel at the base'of said flange, a cast reinforcing band. cast in situ of a lower melting point metal, enclrcling said flange and in continuous intimate contacttherewiththroughout theirzone 1 ofoverlap, said cast reinforcing band including a well-defined shoulder extending around the outersurface of said band over which the lower skirt portion of asheet metal sealing capmay be crimped to anchor said cap to said cast band.

HOWARD W.'DODSON.

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