US 2670868 A
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Description (OCR text may contain errors)
Patented Mar. 2, 1954 Harry E. Stover and Georg Ohio, assignors to Anch poration, Lancaster,
Delaware Continuation of application Serial No.
M. Stuntz, Lancaster, or Hocking Glass Cor- Ohio, a corporation of J uly'19, 1948. This application March 26, 1951,
Serial No. 217,492
1 Claim. 1
The present invention relates generally to a sealed package and the component parts thereof, and more particularly to an improved glass container, metal closure cap, and the package formed thereby.
Various foods and other products are packed in glass containers and sealed with closure caps. Most of such products require a hermetic seal, and many require a partial vacuum within the package. In view of the quantity sold and their mass production, the sealing must be at a rapid rate. The assignee of the present application has developed machines which will hermetically seal with a high vacuum therein as many as 250 normal size containers a minute (about four each second) and as many as 500 small size containers a minute. Imperfect seals must be kept at an absolute minimum.
Under these severe conditions of mass production, the requirements as to closures, containers and the seals formed are extremely exacting. The problems involved are different than exist with closures that have their skirts reformed after being placed over a container mouth. In addition, due to limitations in the manufacture, glass containers vary considerably both in size and out-of-roundness from a true standard. Likewise closures vary in size from a true standard, but to a lesser extent. It is not practicable to gauge each container or closure. Permissible tolerances are substantial and must be permitted. In many cases the containers vary more than the prescribed tolerances, and yet perfect seals have to be made readily on them by closures that are merely pushed down over the container sealing surfaces, without any reforming of the closure skirts.
Under such conditions, perfection in seals and their component parts is necessary. .Slight differences in construction change failure into commercial success.
Removal of the closurefrom the container by the housewife is another serious problem. The housewife is not a mechanic, and she usually attempts to pry the closure off with any implement she can find. Hence it is very desirable to have a closure which may be pried off with ease and without breaking the container. I-Ieretofore in prying the closure from the container the implement used would frequently break the container due to the sharp overhangs on the container utilized for holding the closure in place. In such cases particles of glass may fall into the food and the contents are not edible. In some cases, the chipped particles of glass are not noted, and serious injury is occasioned by per- .Sons eating the product with the glass chipsinitu The finish and closure herein overcome these difiiculties.
The housewife also desires a closure and container which may be re-sealed after the contents have been partially consumed so that the remainder may be kept in the refrigerator or elsewhere without spoiling. This objective is also achieved by the present invention.
The present invention aims to provide an improved package and improved component parts therefor which may be effectively sealed by high speed machinery with a minimum of imperfect seals. More particularly, the present invention is an improvement upon Patent No. 1,909,406 and aims to overcome difliculties encountered with said package, both in high speed sealing and in the removal and re-sealing of closures.
An object of the present invention is to provide an improved container, an improved closure, and an improved package formed thereby.
Another object of the invention is to provide an improved closure and container which may be readily sealed by high speed machinery.
Another object of the invention is to provide an improved container which facilitates closure application.
Another object of the invention is to minimize leakers and other imperfect seals.
Another object of the invention is to provide a package which may be readily opened without breaking the container or chipping glass into the product.
Another object of the invention is to provide an improved package which may be easily resealed by a housewife and which forms a better re-seal for preserving unconsumed contents of the package.
Other and further objects of the invention will be obvious upon an understanding ofthe llllLS. trative embodiment about to be described, or will be indicated in the appended claim, and various advantages not referred to herein will occur to one skilled in the art upon employment of the invention in practice.
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 sectional view of the present container and closure spaced from each other;
Fig. 2 is a fragmentary enlarged sectional view showing features of the closure;
Fig. 3 is a fragmentary enlarged sectional view showing features of the container;
Fig. 4 is an enlarged fragmentary sectional view showing the position of the container and closure as the closure is about to be forced down onto the container; and
Fig. .is.an enlarged fragmentary sectional view illustrating t-he relation of the .,closure=and container in sealed position.
Referring again to the drawings illustrating a preferred embodiment of the invention, and more particularly to Fig. 1 thereof, there is -shown=a container I having a cylindrical side wall land a reduced lower end 4. The upperiend.oflthecontainer has an abrupt shoulderj Whichmay be formed by the outward flare of the wall of the container. An annular enlargement 6 spaced above the shoulder 5 is adapted to cooperate-with a closure cap gasket in forming'aseal'andholding the cap on the container.
The annular enlargement 8, shown morezclearly in Figs. 3 and 5, when viewed in section, has a convexsurfaceleading at its-upper sidentoan annular upper concave surface la thatextends along a gentle curve .to .a location adjacent the rirncf .the container. ,An .annular'lower surface 1b.,curvesinwardlyLtoward. the wall .of ,the cone tainer more ,.,abruptly ..than the .upper concave surface and merges into the side wall ,of the container. The annular convex portion of .the enlargement isadapted to be envelopedhy the closure gasket, when a closure is forced onjthe container, toform a hermetic seal andto retain the closure on'the containenas shownmore .particularly in'Fig. 5.
The-gently curved upper surfaceiaffacilitates application of a closure cap to the container and allows ,the closure to ride lower cnthe container when a preliminary seal is formed, as willflbe later more fully described. The lower, more abrupt surface '12) securely'holds the closure on the container. In addition, therounded undersurfacecauses a cap removing-tool or other instrument inserted under the bottom of the closure to slide along without chipping or. breaking thejglass. This latter'feature isimportant in order to avoid breakage and to guard against chipped glass getting into a packaged product.
A slight offset E is provided on the outer side wall slightly below the rim,'which serves'asfthe parting linebetween'the split neckring forming the finishand the solid annular ring forming the rim'in 'the'manufacture of the container. This eliminates fins at this point'and avoids particles of glass which might form and later find theirway into the contents .of the package.
Theiclcsure comprises a cover portion! l and a depending skirt i2. The cover portionhasadepressedpanel it which'is sufficientlylarge to receive the reduced lower end d of the-container whereby the sealed packages 'may be readily stacked without fear of their creeping"sidewise, when "subjected to vibrations and shock, and toppling off.
The skirt of the closure has an annular channel therein spacedclown substantiallyfrom the-cover of the closure and formed by an upper-wall iii, an ,outerside wall I! and a lower wall'or ledge +8. The upper wall iii of the channel is "shown-inclined upwardly and outwardly (Figs-2) an'dthe' outer sidewall Fl may "be substantially perpendicular with respect to the cover part of the closure. Thelower wall i8 may beformed by bending "the "free edge of the closure inwardly sufliciently far to support the underside of a gasket 28 after theclosure is sealed on the-container.
It will be noted-in Fig; zthat'thein'clined'wall I B-cf the annular channel forms a spaceliinto which the upper side of the -gaskct may move.
,-.given by the raised portion. The width of the gasket is substantially equal to the width of the inner..=s'ide.of'the upper wall IQ of the channel, thusfurtherdecreasing the tendency of the gas- Iket 1.to wedgepbetween the closure and the glass finish. ,A gasket Ihaving a thickness of about .090 inch anda-height of about .111 inch aifords excellent results. Preferably the middle of the "gasket is slightly-below the middle of the convex band-2 l ,tas'this relationship affords greater holding power.
.Theimost desirable action in sealing a closure to a container would :be to have the closure forced downwardly .whileretained inaplaneperpendicular .to theaxis ,of thev container that is,to force theolosure .of .Fig.;l straight down on the container. LThis ianotffeasiblein all sealing ma chines. In many instances as iliustrated in Patent iNo.2,525,l99, the container moves along. a
path andpulls ,a closure out of a chute, steam being injecteldhetweenthe container rim andunderside of ,the closure. The closure then moves down over .the pper curved surface tothe relaticnship shownin'Fig. 4. "In this relationship the gasket should be incontact withportions of the" annular jenlargement throughout its circumferenceltoiform a preliminary'seal. Usually. a stationary:member"wipes over a portion of the closureasit moves along with '.the containerin order to insure .that'the closure 'gasket'fifi anda portion ofthe annular container enlargement are firmly in contact throughout 'their circumfershoes, so that when steam condenses in the-headspace of the container a partia1;vacuum will'be formed 'inthegpackage. The'forrnation of this secure ,preliminarysealis of utmost-importance as it determines .whether' the final-sealed; package will have asuitablevacuum' therein. When .itis
recalled that'the. seals may be -madeatia rate as highas 250a minuteitisrea'dily appreciated that the seal must" be quickly 'and easily formed.
iWith the; present gently curving upper-surface 1a,..a closure and its gasket may readilymove down. along theupperpart 'of the curveunt-il it restsjagainst" anappropriate --'diameter 'portionpf the uppergcurved surface. The closure is not-held uprelatively high on any :straight taper'where it is subject to "being objectionably jarred or T shifted instead -the 'closure -rides relatively *low sothat" it-is *notiikelywo fall olf'the' container or to lose a partial vacuum formed by the--con-' densing injected "steam.
The-relatively small diameter afforded by the upper portionsof the curved surface'-'7a facilitates reception of closures which may be undersize even though the-ccntainer-- may 1 be oversize.
'The upper curved-'surfacela, when viewed -'in section; mayhe formed'along' anarc of a circle having-aradius ofabout two-tenths of an inch,
thus providing a smoothly curved concave surface over which the gasket slides in the-sealing operation. "The enlar-gement adjacent'its maximum diameter is a smoothly curved concave surface when viewed in section.
Subsequent *to formation of the preliminary sealpshown in Fig. 4,'the' final seal-may be formed by --forcing the closure fully down by means'of a'pressure belt-as shown in-Patent No. 2,529,199,
An important feature of the present invention is the hardness of the gasket. A gasket having a Shore durometer hardness of from 70 to 85 (this terminology being well-known in the art) has been found to give unexpected results. A gasket of this hardness is suificiently soft to accommodate a widerange of variations in the containers and form a seal on a minimum size and yield sufiiciently to go on the maximum size container. In addition, the gasket is sufficiently hard so that when it is sealed over the enlargement on the container, the co-action between the gasket and the enlargement is such as to hold the closure securely in place even when a substantial pressure is developed in the container, as a result of processing or sterilizing the product after it is sealed. It is common for pressures to be built up as high as eight, ten or twelve pounds per square inch during steriliza tion. The heat of sterilization also softens the gasket to some extent but in spite of this the co-action of the gasket and the enlargement of the present invention will hold the closure securely in place.
As shown the gasket envelopes the enlargement 6 at its maximum diameter with a greater portion of the gasket engaging below the middle of the enlargement than above it. The portion above the mid area of the enlargement tends to force the cap ofi the container, whereas the portion below it secures the cap on the container. The inwardly extending edge 18 of the closure engages the gasket sufilciently far inwardly so that it holds the underside of the gasket securely in place under the enlargement on the finish.
The outwardly and upwardly inclined side 16 forms a space I 3 over the upper side of the gasket allowing the gasket to yield more by moving into the space. This prevents or minimizes the possibility of the inner upper corner of the gasket being forced upwardly or concentrated between the glass finish and the inside of the skirt of the cap at and directly above the upper side of the channel. The wedging of the gasket in this space tends to impair the seal by an excessive upward pressure tending to raise the closure.
The thick wall of the finish adjacent the rim of the container is a distinct advantage. When the glass leaves the mold, it is soft due to its high temperature, and any thin portions tend to deform. The finish of the present invention provides a thick wall which supports the glass of the finish and maintains it closer to the prescribed standard size.
It will be seen that the present invention provides an improved closure, an improved container, and an improved seal formed thereby. The closure and the glass finish are particularly adapted for high speed sealing with a minimum number of leakers or otherwise defective seals. The closure readily moves down over the gently curving upper surface of the sealing zone to form a preliminary seal; in this relationship the closure is positioned relatively low on the container so that it is not easily dislodged. When pushed fully home to form the final seal the closure is securely held in position by the co-operation of the enlargement with the gasket and may be readily removed without chipping glass from the container into the contents. The inclined upper side of the closure channel and the inwardly extending lower edge co-operate to prevent or minimize the tendency of the gasket to roll and the tendency of the upper edge of the gasket to wedge between the closure and the finish. This further facilitates the sealing operation at high speeds and minimizes "leakers and imperfect seals.
This application is a continuation of application Serial No. 39,418 filed in the United States Patent Ofiice on July 19, 1948 and now abandoned.
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 our invention, we claim:
In a sealed package of the forced-on closure type, the combination of a glass container having an annular enlargement on the side thereof comprising in vertical cross section a maximum diameter portion spaced from the rim of the container and presenting an outward convexly rounded surface, an annular gasket-guiding and initial sealing surface thereabove of gradually diminishing diameter and outwardly facing, continuously smooth, gradually curving, concave shape merging smoothly into a vertically disposed generally cylindrical wall portion adjacent the rim, an annular closure retaining surface of diminishing diameter and outwardly facing, continuously smooth, more abruptly curving, concave shape forming the lower surface of said enlargement and merging into a vertically disposed generally cylindrical container wall below said enlargement, and a closure cap of the type adapted to form a hermetic seal by being forced over said enlargement without reformation of the closure skirt, said closure cap having a cover part and. 2. depending skirt, an annular channel at the lower part of said skirt with the bottom of the skirt flanged inwardly to form the bottom of the channel and a support for the underside of a sealing gasket, a relatively thick narrow annular gasket in said channel supported by said flange and pressed into firm sealing engagement with the convexly rounded portion of said annular enlargement, said gasket engaging under said abruptly curved closure retaining surface to hold the closure firmly on the container and to exert sufficient holding force to overbalance substantially the upward pressure occasioned by that portion of the gasket compressed against the upper surface of said enlargement.
HARRY E. STOVER. GEORGE M. STUNTZ.
References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 697,491 Kalling Apr. 15, 1902 734,140 Schram July 21, 1903 933,122 Schram Sept. 7, 1909 1,117,792 Colby Nov. 17, 1914 1,151,875 Haslup Aug. 31, 1915 1,640,940 Jaeger Aug. 30, 1927 1,909,406 Holland May 16, 1933 2,025,031 Algeo et al. Dec. 24, 1935 2,079,813 Podel May 11, 1937 2,080,144 Lufkin May 11, 1937 2,080,747 Scofield May 18, 1937 2,318,611 Jackson May 11, 1943 2,437,515 Glocker Mar. 9, 1948 2,492,144 Gcra Dec. 27, 1949 FOREIGN PATENTS Number Country Date 484,161 Great Britain Oct. 18, 1937