US2309308A - Closure cap and method of making - Google Patents

Description

Jan. 26, 1943. J. c. GIBBS CLOSURE GAP AND METHOD OF MAKING Filed Feb. 15, 1940 INVENTOR JZ/tn (f 6135 ATTORNEY Patented Jan. 26, 1943 UNITED STATES PATENT OFFICE CLOSURE CAP AND METHOD OF MAKING John C. Gibbs, New York, N. Y., assignor to Anchor Cap & Closure Corporation, Long Island City, N. Y., a corporation of New York Application February 15, 1940, Serial No. 319,049

4 Claims. (Cl. 113-121) The present invention relates to a method of making closure caps and to the closure formed thereby and more particularly to a method of making a screw cap with lugs which are formed from an inturned wire or bead and to the resulting closure.

The present invention is an improvement in a closure and in the method of making a closure of the type illustrated in the James S. Hardiman Patent No. 1,810,706. In such closures it is desirable to provide lugs which will not ride over the thread projections on the container. Due to limitations in the manufacture of glass containers it is necessary for the underside of the glass thread to be rounded which tends to force outwardly the lug of a cap being applied causing it to jump over the thread. Since closures are applied by machines the force utilized in screwing them on can be and usually is much greaterthan that utilized in manual application. Hence it is important that cap lugs be strong and effective. Failure of a cap frequently means the loss of a package as the ineffective seal may not be detected.

The present invention aims to provide a closure and method of making in which the lug is more effective than heretofore and has a greater inward extension in order to obtain a better hold on the thread of the container. This is achieved without increasing the cost of the closure or its method of manufacture. The invention aims further to provide a lug closure cap in which the decoration on the cap has a fixed relation to the lug so that the cap decoration will have a predetermined relation to the container and the label thereon when the cap is applied to the containers.

An object of the present invention is to provide an improved method of making a closure of the concealed lug type.

Another object of the invention is to provide an improved lug closure which will form a secure seal on a container.

Another object of the invention is to provide an improved method of making a closure with stronger and more effective lugs without increasing the cost thereof.

Another object of the invention is to provide a closure with an inturned bead having substantially more metal at the lug portion than elsewhere therein.

Another object of the invention is to provide a closure cap having the decoration thereon in predetermined relation to the lugs of the closure.

Other and further objects of the invention will be obvious upon an understanding of the illustrative embodiment about to be described, or will be indicated in the appended claims, 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 drawing, forming a part of the specification, wherein Fig. l is a perspective view of a flanged blank formed from sheet metal and illustrates the first step in the method of forming the present closure;

Fig. 1a is a sectional view along the line Ia.la of Fig. 1;

Fig. 2 is a sectional view through the closure illustrating the bead intermediate the lugs in section and a lug in elevation at the end of the second step in the method of forming the closure;

Fig. 2a is a sectional view through the lug along the line Z a-2a of Fig. 2;

Fig. 2b is a sectional view along the line 2b2b of Fig. 2a illustrating the upper side of the lug and adjacent bead;

Fig. 3 is a sectional view of the cap through the bead thereof with the finished lug in elevation illustrating the third step in the method of formation of the cap and the finished cap;

Fig. 3a is a sectional view through the lug along the line 3a--3a of Fig. 3;

Fig. 3b is a sectional view along the line 3b3b of Fig. 311;

Fig. 4 is a perspective view of the finished closure and a glass finish to which the closure may be applied, the decoration on the closure being in predetermined relation to the lugs;

Fig. 5 is a fragmentary sectional view of an other embodiment of the invention taken through the lug portion at the end of the second step in the formation thereof; and

Fig. 5a is a fragmentary sectional view corresponding to that shown in Fig. 5 through the lug of a finished cap.

Referring again to the drawing wherein a preferred method of making the closure and a preferred embodiment of the closure are illustrated. there is shown in Figs. 1 and 1a a blank having a cover portion I, a dependent flange or skirt 2 with tabs 4 located at intervals thereabout. In the present closure only two tabs are shown as two lugs are intended to be formed. It will be understood that any desired number of lugs can be formed in the closure in which case there will be a corresponding number of tabs 4 in the blank shown in Fig. 1. It is customary in stamping blanks for closures to stamp them from a very large sheet, which in many cases is decorated. Since the blanks are circular, there is always a space of waste metal intermediate the portions of the circles, which are not tangent. The tabs 4 may be stamped from the waste metal at those portions without reducing the number of closures which can be formed from a sheet of metal. In this way, the tabs 4 may be made from metal which would otherwise be wasted and hence do not increase the cost of the sheet metal in the closure. The base of the tabs 4 is of greater width than the middle and upper portions thereof, preferably, withthe sides of the tabs 4 Joining the bottom of the cap in an arcuate curve 5 to connect the finished lugs more securely with the bead of the closure as will be described hereinafter.

Since the tabs 4 determine the position of the finished lugs in the cap, the decoration on each closure stamped from a decorated sheet of metal will have a fixed relation to the lugs. Likewise the lugs or threads on a glass container bear a fixed relation to the mold parting line and to the shape of the container and the label can be applied thereto to have a fixed relation to the decoration on the cap. Thus one looking at the label would be in position to read the printing on the cap without turning the container around.

In the second step of the method of manufacture the blank, illustrated in Figs. 1 and 1a, is presented to a suitable die in which the edge of the cap is turned inwardly and upwardly to form an inturned wire or beaded edge. 6 as shownin Fig. 2. The beaded edge intermediate the lug portions is flattened outwardly against the skirt of the cap to mak the diameter of the cap at these portions as large as is reasonably possible so that the clearance of the threads at the end of the container and the inner side of the bead 6 i will be sufficient to avoid interference during the application of the cap to a container. In the beading operations, the tabs .4 are rolled upwardly and permitted to form a much larger portion as shown at 4a, which is not flattened.

sure, illustrated in Figs; 3, 3a and 3b, is directed to increasing the strength of the partially formed lugs 4a and to increasing the inward extension of the lugs to obtain a better grip upon the thread of the container. The blank shown in Fig. 2a is presented to a second die in which the bottom of the skirt of the cap at the lugs is forced upwardly as shown at 8. Preferably both i the lugs and the bottom of the skirt are forced upwardly so that the bottom of the skirt is arched upwardly slightly at the lugs to serve a two-fold purpose; first, the metal pressed from the skirt of the cap forces the inner side of the lug further inwardly to get a greater extension of ,the lug and secondly the arched portion in itself reinforces the lug to resist the downward pressure which is applied thereto by the thread on the container in the application of the cap to the container.

Simultaneously with the indentation of the bottom of the cap at the lugs, th upper sides of the lugs are forced downwardly as shown at I which further increases the inward extension of the lugs 4b by collapsing the lugs in a vertical direction. Preferably the inner edge of the lug abuts against a cylindrical portion of the tool used in the lug forming operation to limit the inward extension of the lugs. In this way the diametrical distance between lugs is accurately determined in each cap. The preferred crosssectional shape of the lugs is shown in Fig. 3a, it being understood that other shapes may be utilized, if desired. The curved portion 5 shown more particularly in Fig. 1a connects the tab 4 with the upper edge of the bead to tuck in, as it were, the outer sides of the lug and connect them securely. to the bead and form, in effect, guys tending to. hold and support the lug against the downward pressure applied by the threads on the container in the application of the cap. The arcuate connecting portion I cooperates with the alrches 8 in the lugs to form a strong construe t on.

After the formation of the cap, it is customary to apply a liner ll made of waxed pulp or other suitable material commonly used for this purpose.

The side elevational view of the finished cap is shown at Fig. 4 together with the preferred form of glass finish to be used therewith. It will be noted that the bottom of the skirt of the cap is shown indented slightly at the lugs in Fig. 4 but not sufficiently to mar materially the appearance of the closure. Sheets, from which the closures are made, may be lithographed so that the resulting closures are a solid color or decorated with any desired design or colors. Where the decoration is printing or a design, it will bear a fixed relation to the position of the lugs by reason of the fact that the lugs are formed from tabs stamped from the waste metal intermediate nontangential portions of the blanks. The label portion of the container usually bears a fixed relation to the threads or lugs on the container, and the cap decoration and the container decoration may be made to have a fixed relation to each other. In applying the closure to the container, lugs 4b'pass between the'ends of the thread projections I 2 and are drawn down by the inclined lower surfaces thereon to form a tight seal.

Figs. 5 and 5a illustrate a variation of the lug shown in Figs. 1 to 4. The skirt portions intermediate the lugs are preferably as shown in Figs.

' 2 and 3. The lug portion i4 is preferably turned in with the free edge ii of the metal extending downwardly. The tabs at the lug portions may be longer than the tabs illustrated in Fig. 1 to provide the additional metal desired. When the portion I4 is rolled further inwardly and collapsed vertically to form the finished lug l4a (Fig. 5a.), the free edge l5 of the metal follows the inside of the skirt of the cap into substantially the form illustrated in Fig. 5a. This construction provides a somewhat stronger lug and facilitates the attainment of uniformity in the inward extension of the lugs. When the inner side of the lug abuts against the tool which limits the inward movement of the inner edge of the lug, the free edge l5 can be rolled further to take up irregularities. In other words the position of the edge IS in the finished lug will vary with the initial length of the tabs and with other variations in the forming operation.

A particular advantage of the tabs in the formation of the lugs is that the tabs provide suming the bottom of the skirt.

cient metal to minimize and to eliminate any depression or irregularity in the bottom edge of the cap occasioned by the formation of the lugs. This feature is illustrated in Fig. a where the skirt of the cap is of uniform length and with the external contours at the lugs conforming to the external contour of the rest of the skirt and may be applied to the type of lug shown in Fig. 3. The additional metal in the tabs affords sufficient metal to form the lugs without indent- The extra metal for the lugs has heretofore been obtained by indenting the bottom of the skirt.

It will be seen that the present method is simple and effective in forming lug closures from metal turned upwardly and inwardly into the closure. There are no raw edges exposed and hence rusting is prevented. The lugs embody substantially more metal than the rest of the bead of the cap without increasing the cost of the metal for the cap since the tabs are provided from waste material. In addition the decoration on the cap may be fixed with relation to the lugs without additional cost. The lugs are reformed to increase their strength and holding power and also to increase the distance that they extend inwardly from the side of the closure thereby to extend further under the lower side of the thread on the container to obtain a good grip on the container thread. The method is simple and the resulting closure is strong and durable. By having the die in the third operation of a fixed diameter at the lugs, it is possible to force the metal of the lugs in the vertical collapsing operation until it abuts against the p member inserted within the closure.

In this way the diameter between the lugs is in efiect gauged automatically in the third operation. This is quite important as the closure may scratch the glass if it fits tight on it at the lugs and this would increase breakage. The tabs provide sufficient excess metal for forming the lugs without requiring indentations in the skirt of the cap at the lugs, which are objectionable to many users.

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 sheet metal closure cap comprising the combination of a cover portion and a uniformly deep depending skirt having integral narrow tabs of metal depending from the flange and spaced by relatively wide intermediate skirt portions of uniform length, the free edges of the tabs being continuous with the lower edge of the skirt, said tabs being widest at their junction with the skirt, the lower margin of the skirt including the tabs being turned inwardly to constitute a continuous closed bead having substantial enlargements at the tab portions, the enlarged portions of the bead formed from the tabs being flattened to form lug portions extending inwardly from the cylindrical skirt.

2. The method of making 'closure caps, which method comprises forming a blank from sheet metal having a uniformly deep cylindrical flange with a continuo s lower edge enclosing narrow depending tabs on the flange, the tabs being spaced by relatively wide intermediate skirt portions of uniform length, turning the lower continuous edge of the blank including the narrow tabs and the relatively wide intermediate skirt portions inwardly and upwardly to form a continuous inturned wire edge or bead having enlargements at the tab portions and a substantially uniform smaller size at the intermediate portions and simultaneously with the formation of the bead forcing the bottom of the blank upwardly and the top of the inturned edge downwardly at the enlarged inturned tab portions to collapse them and to force their inner portions further inward to increase the distance they extend inwardly beyond the inward extension of the rest of the bead.

3. The method of making a closure cap, which method comprises forming a blank with a uniformly deep cylindrical flange having a continuous lower edge enclosing depending narrow tabs on the flange, the tabs being spaced by wide intermediate skirt portions of uniform length, said tabs increasing in width at their junction with the skirt, turning the lower edge of said blank intermediate said tabs inwardly and upwardly into an inturned bead or wire edge of substantially uniform size, simultaneously turning said tabs inwardly and upwardly into an inturned bead having lateral and vertical dimensions substantially greater than the normal portions of said inturned bead or wire edge, so that all the bead portions merge smoothly and continuously and reforming said inturned edge at said tabs to reduce the vertical dimension thereof and to increase the distance said tab portions extend inwardly beyond the rest of the bead thereby to increase the lug projection thereof.

4. The method of making a closure cap, which method comprises forming a blank with a uniformly deep depending cylindrical flange having a continuous lower edge enclosing narrow depending tabs on the flange, the tabs being spaced by wide intermediate skirt portions of uniform length, said tabs increasing in width at the junction of the tabs with the skirt to increase the strength of the lug formed therefrom, turning the lower continuous edge of said blank including the narrow tabs and the wide intermediate portions inwardly and upwardly into a continuous inturned head or wire edge, said bead at said tabs being larger laterally and vertically than the rest of the bead and substantially shorter in length than the intermediate portions of the bead, and compressing said enlarged portions in a vertical direction to reduce the vertical dimensions thereof and to increase further the distance they extend inward beyond the rest of the bead.

JOHN C. GIBBS.

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