US2562548A - Closure cap and package - Google Patents

Description

y 31, 1951 R. c. HANSON ,5

CLOSURE CAP AND PACKAGE Filed March 22, 1948 ITOR. 30hr} f f/ansan Y ATTORNEY Patented July 31, 1951 UNITED STATES PATENT OFFICE CLOSURE oAP AND PACKAGE Robert (L'Hanson, Connellsville, 'Pa., assignor' to Anchor Hocking Glass Corporation, Lancaster, Ohio, a corporation of Delaware Application March .22, 1948, Serial No. 16,227

6 Claims. (01. 215-4o) The present invention relates generally to 010 sure caps for receptacles and particularly to 010 sure caps of the force-fit type adapted to be pressed downwardly over the upper end oi areceptacle' or container to form a side seal around 7 the exterior upper portion of the receptacle.

' Where closure caps of the reformable skirt type are applied over container mouths and the cap skirts thereafter reformed to produce a seal against a container sealing zone it is generally feasible to form a seal sufliciently tight as to prevent leakage of pressure from the atmosphere into the container to-lthereby destroy a container vacuum. .In the reformation of such cap skirts the skirt moves inwardly until a gasket is tightly squeezed between the container neck and the closure cap-skirt. While closure caps of the-reformable skirt type are thus desirable they are nevertheless objectionable in that, among other reasons, it. is difficult to form sealed packages with thesame rapidity .as with closures-which are pushed doWnorforce-fitted; relatively .complicated machinery isrequired to reform-the cap skirts to make tight .seals, and relatively, com,- plicated machinery fisrequired for producing a vacuum condition prior to and during .applica% tion and reforming of the closurecap skirt.

For thelforegoing reasons closure .caps ofthe pusheddown, side seal type are extensively utilized for covering the upper ends of .vacuumized receptacles .filled. with various food products. Such closure caps are more readily applied and the containers to which they are applied maybe more readilyvacuumized.

With closure caps of the force-fit side seal typ manufacturing tolerancedifficulties'have been i experienced which interfere with application of caps so as'to maintaina desired vacuum seal; It'is frequently difiicult'to formor maintain a suitable vacuum seal with side seal containers by reason of the fact that individual receptacles or containers of a standard or given size have slight:- ly different sealing zonedimensionsyas well as at other portions thereof; As a-pract'i'ca'l manufacturing matter various tolerancesmustbe allowed and while a given lot of containers may be of a same true standard size, they may in'-' dividually stillbe of slightly varying dimensions. Manufacturing tolerances generally have been kept at a-minimu1n consistent with practical slight out-of-roundness and other manufactdr' ing defects still tend to impairthe formation and maintenance of vacuum seals. Even though a closure cap may .be fitted over a container mouth such variations in. efiective sizes of container conditions 'ofproduction, but this as well i as '2 sealing zones render it difiicult tomaintain hermeticior vacuum seals; air tends to leak ,past a sealing gasket into the container to .causespoilrage of the contents.

Even in those instances where the container is of approximately an exact standard size, difficulty. .in sealing and .maintaining. a vacuum; in the container .arises due to tolerance variations extant in the closure caps and sealing. gaskets themselves. While these dimensional variations may seem slight they are in many cases of sufficient magnitude to impair maintenance of a vacuum within a .capped container.

"In actual practice combinations'all three of the'above dimensional variations occur; The containers, gaskets andclosure caps embody dimensional tolerance variations'from a given standard, rather than merely a container alone or a closure cap alone or a gas'ketalone; Where a minimum size container is. usedwith a gasket having a' maximum effective inside diameter, forming and maintaining .a'vacuum seal is difficult; air'tends'toleak into the container through the relatively loose'seal. Where the container has a sealing zone diameter of maximumsize and is used with a gasket-and closure capof minimum effective diameter, it is often difficult to force the cap and gasket downwardly over' the container mouth. 7

-The present invention aims to overcome or minimize the-above-and other difiicultiesor disadvantages and to securely maintain vacuum or hermetic-seals byproviding a closurecap' adapted to so retain a sealing gasket as to effectively seal a container with maximum allowable tolerances or'dimensional variations, and regardless of existing tolerance dimensions of the container per se;- of 1 the'closure cap per se, 'o'f'tthe gasketper se or of all three in combination. 'The present clo sure cap aims to provideffor"maintaining a gask et' so that thegaske't may seal containers 'o i z'n'in'i mum dimensional characteristics .and to p'rqvme for absorbing what may be termed surplus gasket material when applied to and sealing c0115 tainersl of maximum dimensional variations.

An object of the present invention is to provide a new .and improved closureeap. I

Another object of the invention is to provide an improved closure cap adapted to'formaseal around a side sealingzone adjacent theupp'erend ofwacontainer.

Another object ofthe invention is to provid an improved closure :cap adapted to efiectivelys'eal containers with dimensional tolerances'or manu' facturing variations;

"Anotherrobj ect of the invention isto provide an" A preferred embodiment of the invention has been chosen for purposes of illustration and description and is shown in the accompanying drawings, forming a part of the specification, wherein:

Fig. 1 is a fragmentary view, partly in section, illustrating the present closure cap applied to a container;

Fig. 2 is an enlarged fragmentary sectional view illustrating the closurecap of Fig. 1;

fled form of closurecapembodying the invention; f

Fig; dis an enlargedljfragmentary sectional view taken alon'g the linel8''8 of Fig. 7;

Fig. 9 an elevational view of another modifled form, of closure cap embodying the invention; and v Fig. 10 is van enlarged fragmentary sectional View taken along the. line Ill-l0 of Fig. 9.

Referring more particularly to Fig. 1, there is shown a'sealed package comprising a container or receptaclev I having anupwardly facing mouth over which is positioned a closure cap 2. An airtight seal is formed by a rubber or other gasket 3 located between the lowerportion of the cap skirt 4 and a container side wall sealing zone 5. The container or receptacle 1 is generally made of glass and may have an-upper tapered portion 1 to facilitate application of theclosure cap 2 with the gasket 3 carried-thereby; the gasket seating against the exterior surface of thesealing zone 5. 'I'hecontainer-ofjFig, 1 is illustrative of one shape which may be,;,sealed by closure caps of the present-invention; any other suitabletype of neck or sealing zone may beused. The closure cap is shown made ,from;.-relatively thin sheet metal as such is relatively inexpensive and may 1 s inset stacking seat: I The dished or inclined por- 1 tions l0 and H are adapted to receivethe bottom of a. container toifacilitate vertical stacking of containers on, a shelf.,-;:The closure-cap is preferably sealed to the; container while the mouth of the latter is filled with steam, .the steam subsequently condensing and creating. a partial vacu- 4 um which tends to pull the closure cap downwardly onto the container. In sealed position on a container the sealing zone of the container presses outwardly against the inner circumference of the gasket 3 and the closure cap.

Where the skirt portion 4 of the closure cap and the cooperating container, sealing zone 5 are of exactly standard dimensions there results a correct or optimum squeezing of the gasket and sealing of the closure cap to the container in such manner as to prevent leakage of air under pressure from the atmosphere past the sealing zone and into the vacuumized container. If the container be slightly undersize, or the closure cap slightly oversize, intermediate gasket 3 is not gripped with optimum tightness and there is a tendency or possibility of air leaking into the container past the sealing zone. In other instances the reverse condition may exist namely a minimum size of cap and maximum size of container; in this case difliculty is experienced in forcing the relatively small interior diameter gasket downwardly over the sealing zone 5. Various in between conditions exist intermediate the two aforementioned extreme conditions. The desirability or need of having closely correct dimensions may be appreciated when it is realized that a vacuum of more than twenty inches of mercury is quite generally utilized and that vacuum in excess of twenty-five inches of mercury are common.

The sealing gasket 3 carried by the cap is of preferably rectangular or square cross section and abuts at its upper horizontal portion against the underside of a horizontally extending ledge portion I 4; its bottom surface is held or supported by an inwardly extending edge IS. The portions l4 and I6 are preferably uninterrupted and hold the gasket 3 against change in vertical dimensions. When the closure cap is pushed down over a container mouth the gasket 3 is placed under compression between the container side wall and the skirt portion 4 of the closure cap, as well as between the substantially horizontal edges I4 and IS. The amount of horizontal compression of the gasket 3 depends upon the particular existing differences in diameters be tween that of the sealing zone 5 and that at the cap skirt portion 4. Where the effective distance between the sealing zone 5 and the inside of the cap skirt 4 is small, the gasket 3 is placed under a relatively high compression; where the distance between the exterior surface of the sealing zone 5 and the interior surface of the cap skirt 4 is comparatively great, the gasket 3 is placed under lesser compression. With previous closure caps the gasket sealing pressure or gasket-squeezingtogether pressure varies from a minimum to a maximum, with no provision for accommodating gasket material where the pressure tends to become excessive and to yet create a tight seal at an opposite'extreme condition. r

In order to overcome or minimize such difficulties, the offset vertical skirt portion 4 of the present cap is provided with circumferentially spaced gasket supporting or inwardly extending portions I! (Fig. 3) separated from each other by circumferentially disposed spaces or outward-' ly extending portions l9. Whilethe-portions IT- are referred to as being inwardly extending itv will be understood that this isfor purposes of convenience in description, as the portions I! may be provided by moving the portions l9 relatively outwardly, to leave the portions=l1 project-- 'sion.

Where the present new closure cap 2 is on its container, regardless of the actually embodied tolerance dimensions of the cap and gasket and container, the gasket 3 carried by the cap is pressed outwardly by the container sealing zone so that some of the rubber gasket material moves into the spaces or recesses 20 (Fig. l). Where a minimum tolerance size container and a maximum tolerance size closure cap and gasket are used in combination, the gasket is pressed into the recesses 28 to some such position as is indicated in Fig. 4. As the dimensional characteristics of the closure or gasket or container, or all three together, vary so as to decreasethe' distance intermediate the inside of the gasket backing portions ii and the sealing zone of the container, a greater quantity of gasket material is urged'or pressed into the circumferentially spaced recesses 23; Fig. 7 illustrates a condition wherein sufiicient surplus gasket material has been forced into recesses 26 to completely fill them.

The amount of surplus gasket material varies with the existing dimensional tolerance characteristics of the individual container, individual gasket, and individual closure cap.

A very desirable feature which results from the evenly spaced arrangement of thealternately disposed backing portions ll and recesses 29 is the substantially uniformly distributed sealing pressure against a container sealing zone throughout the height of the gasket backing portions l 'l. Gasket sealing pressure extends over a relatively wide band. With a 47 millimeter cap, a height for the vertical inwardly gasket backing portions ll and recesses 28 of about one-tenth of an inch gives good results.

The inwardly extending upper and lower portions id and i6 tend tov hold the shape and size of the offset skirt portion 4 and of the substantially vertical inset and outset portions 5? and i 9. The portions i i and it are preferably uninterrupted by gasket backing portions ll or recesses 25. and act as strengthening or retaining bands which retain the offset skirt portion t against undue deformation consequent upon the exertion of sealing forces.

While the inwardly and outwardly extending portions l l and it may be formed in the skirt at any convenient stage during manufacture it has been found convenient to form them, in any convenient manner, prior to turning inwardly the lower gasket supporting portion or ledge 16.

In Fig. 6 there is illustrated a horizontal cross section through the skirt of a closure cap and gasket 25 which is generally similar to that illustrated in Figs. 1 through 5. In Fig. 6, however, opposite sides 25 and 2d of the vertically extending gasket backing portions 23 and. of the intermediate gasket receiving recesses 28 are of slightly differing shapes. Closure caps embodying such gasket backing portions, in an offset skirt similar to that illustrated in Figs. 1 and 2, have been gasket receiving recesses.

6 found to perform very well in actual practice when sealed to. containers. It may be that the different angular positions of the wall portions 25 and 25 tends to create a wedging or squeezing actionwhichis directed longitudinally around the gasket 25. In operation the recesses or spaces 28- are adapted to receive or absorb greater or lesser quantities, of surplus gasket material pressed therein by an inwardly positioned container sealingzone; the action is similar to that described'in connection with the closure cap illustrated in Figs. 1 through 5.

A modified form .of the invention is illustrated in Figs. '7 and 8 of the drawings. In this form thegasket backing feature is provided bycircumferentially spaced inwardly extending projections 30, each of which is shown as having rounded surfaces of approximately hemispherical. form. In many instances the projections 30 are not exactly hemispherical but, for purposes of convenience, the projections 39 will be described and otherwise referred to as of substantially hemispherical form. The staggered relationship of the inwardly extending projections 35 provides a backing efiect which is distributed or extends over a relatively wide zonewhereby, when the cap is pressed down over a container mouth, resultant sealing forces are distributed over substantially the full width of the sealing zone or correspending height of the offset closure. cap, portion 3!.

The form of the invention illustrated in Figs. 9 and 10 difiers from that disclosed and described in connection with Figs. '7, and 8 in that the pluralityof circumferentially spaced depressions or indentations 32 which form the gasket backing portions are of slightly larger diameter than the gasket backing portions 3c of Figs. 7 and; 8, and also in that theyv are not arranged in the staggered relationship. The forms or arrangements illustrated in Figs. 1 through 8 are preferred to that illustrated in Figs. 9 and 10 since the gasket backing portions illustrated in the former group of figures applies sealing pressure more uniformly throughout the sealing zone of a container, however, in some instances, it may be desired to utilize the form illustrated in Figs.

9 and 10. g

It will be seen that the present invention providesa new and improved force-fitted type of closure cap. which is adapted to be sealed with receptacles or containers to provide an efiective hermetic or vacuum seal in a greater number of instances than is true of previous closure caps and containers. Anoffset gasket-holding skirt has a plurality of circumferentially spaced gasket backing or supporting portions with intermediate The recesses absorb surplus gasket material when the gasket is placed under compression by being applied to a container. The amount of surplus gasket material squeezed into the circumferentially spaced surplus-receiving portions varies, depending upon the dimensional tolerance characteristics of the particular closure cap, gasket, and container to which the cap and gasket are applied. Sealing pressure is distributed substantially uniformly throughout the height and length of the sealing zone.

As various changes may be made in the form, construction and arrangement of the parts herein without departing from the spirit and scope of the invention and without sacrificing any of its advantages, it is to be understood that all matter herein is to be interpreted as illustrative and not in a limiting sense.

Having thus described my invention, I claim:

1. A container closure of the type adapted to be applied to a container to form a seal against a side wall thereof without reformation of the closure skirt, comprising a cover portion, a depending skirt having a substantially smooth and uninterrupted upper portion and a lower portion of greater diameter than said upper portion, said lower portion having around its peripher intermediate top and bottom edges thereof a plurality of circumferentially spaced inset gasket backing portions separated from each other by unoccupied gasket-receiving spaces, a substantially smooth and uninterrupted ledge connecting the top edge of said lower portion with a bottom part of said upper portion, a substantially smooth and uninterrupted ledge extending inwardly from the bottom edge of said lower portion and an annular elastic gasket lying wholly intermediate said ledge portions and supported at circumferentially spaced locations around its outer periphery on said inset backing portions, portions of the gasket circumferentially intermediate said spaced locations bridging said gasket-receiving spaces of the depending skirt.

2. A container closure of the type adapted to be applied to a container to form a seal against a side wall thereof without reformation of the closure skirt, comprising a cover portion, a depending skirt provided with a lower portion having around its periphery and extending across the major portion of its width a plurality of circumferentially spaced inset gasket backing portions separated from each other by unoccupied gasketreceiving spaces, an upper skirt portion of lesser diameter than said lower portion and uninterrupted by gasket backing portions, a substantially uninterrupted ledge connecting the top edge of said lower portion with a bottom part of said uninterrupted upper portion, a substantially uninterrupted ledge extending inwardly from the bottom edge of said lower portion, and an annular elastic gasket lying wholly intermediate said ledge portions and resting at circumferentially spaced locations around its outer periphery against said inset backing portions, portions of the gasket circumferentially intermediate said spaced locations bridging said gasket-receiving spaces of the depending skirt.

3. A container closure as set forth in claim 2, in which said inset gasket backing portions have generally convex inwardly disposed surfaces and extend generally vertically across said lower portion of the skirt.

4. A container closure as claimed in claim 1,

in which said inset gasket backing portions have substantially hemispherical inwardly disposed surfaces.

5. A container closure as claimed in 1, in which said inset gasket backing portions have substantially hemispherical inwardly disposed surfaces and are located in substantially staggered relationship.

6. A sealed package comprising a container having an annular sealing zone extending about its side wall below the upper edge thereof, a closure cap having a cover portion over the container mouth, a skirt depending from the cover portion having a substantially uninterrupted upper portion and a lower portion of greater diameter than said upper portion spaced outwardly from the container sealing zone, said lower portion having around its periphery intermediate top and bottom parts thereof and generally coextensive with said sealing zone a plurality of circumferentially spaced substantially vertically disposed inset gasket backing portions separated from each other by gasket-receiving spaces, a substantially uninterrupted ledge connecting the top part of said lower portion with a bottom part of said uninterrupted upper portion, a substantially uninterrupted ledge extending inwardly from the bottom part of said lower portion, and an annular elastic gasket lying wholl intermediate and confined between said ledge portions and resting at circumferentially spaced locations around its outer periphery against said circumferentially spaced inset backing portions, portions of the gasket circumferentially intermediate said spaced locations being squeezed at least partially into said gasket-receiving spaces by the container sealing zone.

ROBERT C. HANSON.

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

UNITED STATES PATENTS Number Name Date 1,327,963 Ramsey Jan. 13, 1920 1,488,567 Taliaferro Apr. 1, 1924 1,616,518 Taliaferro Feb. 8, 1927 1,634,724 Ramsey July 5, 1927 1,909,406 Holland May 16, 1933 2,005,318 Ingram June 18, 1935 2,025,031 Algeo et a1. Dec. 24, 1935 2,136,545 Gibbs Nov. 15, 1938 2,441,918 Hoge May 18, 1948

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