US2275220A - Method of and apparatus for making closure caps - Google Patents

Description

March 3, 1942. E, M, ENKUR 2,275,220

METHOD OF AND APPARATUS FOR MAKING CLOSURE CAPS Original Filed Fb. 20, 1935 5 Sheets-Sheet l 5 Sheets-Sheet 2 March 3, 1942.

I IIIWIIIIIIIIII a "IIIIIIII 3maentor IIIIIII 1I III IIII,IIII.

/ /III!IIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIII March 3, 1942. E. M. ENKUR 2,275,220

METHOD OF AND APPARATUS FOR MAKING CLOSURE CAPS v Original Filed Feb. 20, 1953 5 Sheets-Sheet 3 v gmu $8 (Ittorneg 5 shts-sheet 4- WVW . I attorney I March 3, 1942.

E. M. ENKUR METHOD OF AND APPARATUS FOR MAKING CLOSURE GAPS Original Filed Feb. 20., 1953 Imvento Eda/and Mfm March 3, 1942. E. M. EN UR 275,220

METHOD OF AND APPARATUS FOR MAKING CLOSURE CAPS Original Filed Feb. 20, 1933 5 Sheets-Sheet 5' a & v x

' Q I i i \r I Patented Mar. 3 1942 A'Nn mami'rus ron MARIN CLOSURE cars METHOD OF Edward M. Enkur, Baltimore, Md., assignor to Crown Cork & Seal Company, Inc., Baltimore, Md a corporation of New York Original application February 20, 1933, Serial No.

657,734. Divided and this application ary 6, 1935, Serial N0. 5,312

Febru- 41 Claims. (01. 153-48) This invention relates to new andimproved methods of and apparatus for making receptacle closure caps.

The cap'of the presentinvention is of the type adapted for use with bottles, jam, or other recepthese attempts have fallen short of the desired result in one respect or another. In some cases tacles having external threadsor lugs on the necks thereof. More particularly, the cap is of the general class known-in the art as lug caps.

Caps of the lug type are well known, and have been made by many 'difierent methods, and have embodied a great variety of different constructional details. The presentcap, when compared with devices of the prior art, has certain fundamental structural differences, which result in definite advantages, as will be pointed out below.

It is a primary object of the present invention to provide a cap of the lug type, in which the lugs'are hidden fromview when the cap is in use upon a receptacle. .It is a. further object of, the

invention to provide a cap having lugs concealed the lugs were made up of a single thickness of metal, and were defective because of their inherent weakness, or because they presented a raw edge for contact with the receptacle thread. In other cases the lower edge of the cap'skirt was necessarily provided with indentations or other deformations at points adjacent the lugs. In still other constructions, it was necessary to Provide'an outwardly rolled head on the lower edge of the skirt to hide the lugs, and such bead dewithin the cap'skirt and constructed in such manner that no disfiguring indications or marks appear upon the skirt of the cap adjacent their location. a V

It is a further object of the invention to provide a cap having a skirt. provided with interiorly disposed locking lugs which do not impair the uniformity of appearance of the exterior surface.

of the cap.

It is a further object of the invention to provide a cap of the concealed, internal lug type in which the material of the cap adjacent the lower edge of the skirt is not-deformed to a degree suf-- ficient to injure the lacquer coating which is conventionally applied tothe cap making material before the same is formed into the completed article.

It is a further object to provide a cap of the type specified, in which no raw ed'ges are ex-' posed so as to be contacted by the hands of a user, or to engage directly a receptacle thread.

It is a further object of the invention to provide a new and improved specific lugstru'cture, characterized by great strength and rigidit'm in which .2. turned edge constitutes a reinforcing member, and serves the additional function of.

presenting a rounded thread engaging surface.

In the past many attempts have been made to design and manufacture a commercially satisfactory lug cap having a smooth exterior surface; and provided with inwardly projecting locking lugs which are concealed when the cap is on the receptacle, and the location of which is not irr-v dicated by indentations or other disfiguring marks on the exterior of the cap skirt. All of stroyed the smooth uniform appearance of the cap. Certain prior art constructions, in which the lower edge of the wardly and upwardly and pressed into a flat fold or hem in contact with the inner face of the skirt and merging with the bottom of the skirtin a sharp fold line orcrease, have been found defective because the lacquer coating on the cap making metal cracks and chips off along the sharp fold or crease, with a consequent ruinous effect 0 upon the appearance of the completed cap.

By the construction embodied in the cap of the present invention, all of the defects of prior art caps of this general type are avoided, and all of the objects of the invention accomplished.

The cap of the present invention comprises a skirt having its lower edge rolled inwardly to form an interiorly disposed, circumferential bead, the cross-sectional curve of which is, at no point,

sharp enough to injure the lacquer coating on the capmaking material. The cross-sectional Q curve which marks the juncture between the.

' lower part of the cap skirt and the inwardly rolled bead isconstant around the entire circumference of the skirt, and consequently, the

lower edge of the skirt presents a uniformly rounded surface, entirely devoid of indentations or other deformed spots. 7

The inner surface of the inwardly rolled bead is provided at spaced points with inwardly proiecting, reinforced: rounded-locking lugs. The lugs may be formed with various difler'ent specific structures, and several alternative methods of making them may be used. It should be distinctly understood, therefore, that the accompanying drawings, showing two preferred forms of cap and one method of making a cap, are 11- lustrative only, and. that theinvention is in no 7 sense limited to the details thereof.

, In the drawings- I Figure'l is a vertical axial sectional view ofa cup-shaped blank from which the cap of the present inventionmay be made;

cap skirtlwas turned in- Figure 2 is a similar view showing the blank after a preliminary step in the method has been completed;

Figure 3 is a similar view showing the blank after the first bead forming operation has been performed on the edge of the skirt;

Figure 4 is a similar view of the blank after the first lug forming step has been completed;

Figure 5 is a similar view showing one form of completed cap;

Figure 6 is a bottom plan view of the cap of Figure 5;

- cumference with a uniformly inwardly turned Figure '7 is an elevational view of the cap of.

the present invention, showing the smooth exterior surface of the same;

Figure 8 is a bottom plan view of a similar cap, showing a somewhat modified form of lug;

Figure 9 is a vertical axial section of the cap shown in Figure 8, taken through the lugs;

Figure 10 is a topplan view, with a portion broken away to expose the modified form of lug;

Figure 11 is an enlarged vertical sectional view of one edge of the cap skirt, corresponding to the step shown in Figure 2;

Figure 12 is a similar view corresponding to Figure 3;

Figure 13 is an enlarged vertical sectional view through the circular'bead portion after the step represented by Figure 4 has been completed;

Figure 14 is a view similar to Figure 10 but taken on a section through one of the lugs;

Figure 15 is an enlarged vertical sectional view taken through the bead portion of the completed cap;

Figure 16 is a similarview, taken through one of the lugs;

Figure i7 is an enlarged sectional view of the completed cap on a receptacle, showing the manner in which the lug engages a receptacle thread;

Figure 18 is an enlarged top plan view, partly in section, showing a specific lug structure;

Figure 19 is a vertical sectional view of an apparatus which may conveniently he employed for performing the step in the method represented by Figure 2;

Figure ,20 is a similar view; with certain parts omitted, showing the first curling die;

Figure 21 is a similar sectional view of the apparatus taken on line 2i-2I of Figure 22, and

shows the die which performs the preliminary several cap forming operations.

Figure 25 is a partial vertical sectional vie head, is constant on all axial sections.

lower edge 21, the cross-sectional curve of which is constant around the circumference of the cap, to present a uniform appearance. The material of the cap interiorly of the rounded edge 21 continues inwardly and upwardly in a roll or bead 28. This bead is substantially circular in cross-section at all points around the circumference of the skirt except at certain spaced points where the lugs are situated. 'I'he'bead at the latter points is unourled, or rolled up to a lesser degree, so that it extends radially inwardly further than the adjacent bead portions to provide locking lugs.

In Figures 15 and 18 the substantially circular, inwardly turned bead portions 28 are disclosed in section. It'will be noted that the crosssectional curve at the lower edge of the cap skirt, between the cylindrical portion thereof and a circumferentially extending line therebelow, such as the locus of all lowermost points 29 on the This curve is continued on substantially the same radius inwardly from that line to form an inwardly disposed substantially circular closed bead along arcuate sections of skirt circumference. In Figures 16, 17 and 18, which show the lug in cross-section, it will be seen that although the outer curve between the skirt and the line of the points 29 is the same as at the bead portions, the cross-sectional shape of {the inwardly extending roll 30 is different, is somewhat flattened, or is struck on a circle of large radius. As a result,

the end portion of the skirt at these placesexof anapparatus adapted to perform an alternative method.

Figure 26 is an enlarged detail of the same prior to the uncurling action.

Figure 27 is a similar view, at the completion of the uncurling step.

- lugs.

tends inwardly beyond the adjacent closed bead portions and forms locking lugs 3|. Preferably the edge of each of the lugs is turned outwardly, as at 32, to provide a concealed edge, to function as a reinforce for the lug, and to present a rounded thread engaging surface 33.

The lug of'the present invention has a thread engaging surface which, as stated above, is rounded cross-sectionaily as disclosed in Figures 5, 9, 16 and 17. The thread engaging surface is also rounded in a direction circumferentially of the cap, as shown in Figures 6, 8, 10 and 18.

It will thus be seen that the skirt of the cap of the present invention is turned inwardly throughout its entire circumference to form a concealed edge, which edge is curled or rolled upwardly to provide a continuous bead, and that the head at spaced points is unourled, or rolled up to a lesser degree to provide inwardly extending locking lugs. Whereas the bead is circular in cross-section and substantially closed along the arcuate sections 23, it is open and extended inwardly at spaced portions 3| to form locking At the open portion, the edge is turned outwardly at 32, in order to reinforce the lugs and also to provide a rounded thread contacting a surface.

It will also be noted that the lugs are horizontally aligned with the intermediate bead sections. The bottom of each of the uncurled portions is aligned with the closed bead portions so that the cap presents a smooth lower edge, and

the tops 83 of all of the lugs are substantially in alignment with the upper surface of the bead portions.

Where in the claims the cross-sectional shape of the roll at the lugs is referred to as being curved on a larger radius, I mean any shape, including substantially flat, which is less sharply curved than the external curve at the lower edge of the cap skirt.

The lugs have been described as portions of the rolled end of the skirt, or bead, which are uncurled, or rolled up to a lesser degree than the adjacent portions, and these terms must be understood to relate to structure, and not to the method of manufacture, as the lugs may be made by curling the entire bead and subsequently uncurling, or unrolling portions thereof. On the other hand,-they may be formed by simply refraining from curling certain portions of the bead as much as other portions are curled. Also, the lugs might conceivably be formed by axially flattoning and radially extending certain portions of the bead by applying force to the top of the head, with the bottom supported upon an anvil having a forming groove with a cross-sectional curve corresponding to the desired uniform curve to be imparted to the exterior of the lower edge of the cap.

In Figures 8, 9 and 10, a cap having a some-.

what modified form of lug is shown. This type of lugmay conveniently be for-med by a method similar to the method described in this application, but difiering therefrom in certain respects, as is clearly pointed out in the co-pending application of Edward M. Enkur, Serial No. 660,927,

filed March 15, 1933 Patent Number 2,081,804, dated May 25, 1937. The essential difference in the method resides in an additional step, between the steps disclosed by Figures 3 and 4, which comprises bending outwardly on-predetermined arcuate curves, spaced portions of the partially formed bead or wire: Such outwardly bent portions are thenswung inwardly during the course of the step shown at Figure 4.

A comparison between Figures 6 and 8 reveals that the essential difference between the two specific forms of lugs is that the one shown in the latter figure is considerably shorter, circumferentially of the cap, than the first form, but

has substantially the same radial depth. The

arcuate curve 3la of the innermost edge of the lug M is struck on a radius which is a great deal shorter than the radius of the are upon which the inner edge of the lug 3! is struck. Since the radial projection of the two lugs is the same, it follows that the number of degrees on the arc of lug 3] is greater than on lug 3|.

Certain advantages follow in certain cases from having the lug relatively short and deep, as opposed to long and shallow as in the form of Figure 6. It is within the scope of the present invention to make the lug of any desired form and shape, depending upon the particular use to which the cap is to be subjected.

A comparison between the several figures discloses that, although the lugs of the modified form have a materially different shape in plan, they are substantially identical to the first form in section.

A preferred method of making the cap of the present invention is disclosed in the drawings,

and will now be described. A cup shaped blank having a top 25 and a cylindrical flange 26 is made in a conventional drawing operation from a sheet of .metal usually having a lacquer coating on its lower surface, or, in some cases, on both surfaces. In the several forming operations which convert the shell disclosed in Figure 1 into the completed cap of Figure 5, the blank is preferably positioned upside down, as shown, and is moved step by step from one press to the next. The general plan of the machine forms no part of the invention of the present application, and consequently the specific means for simultaneously moving a plurality of blanks in a step-by-step motion to the various stations is not disclosed.

The blank of Figure 1 has a substantially cylindrical skirt 2E, terminating in a rawedge 35, which normally is slightly outwardly flared when the blank comes from the drawing dies. Since in the present method itis necessary to curl the end portion of the skirt inwardly, it has been found expedient to first start the curl by tuming the free edge from its outwardly flared position to a slightly inwardly bent position. This first step in some cases may be dispensed with, but it has been fornd desirable with theusual run of blanks. The result of the preliminary edge bending operation is disclosed in Figures 2 and 11, and it will be noted that the cross-sectional shape of the skirt edge has been changed just enough to facilitate the next curling operation.

The second step in the, method comprises giving the edge of the cylindrical flange a substantially semi-circular, inwardly disposed curl, as disclosed in Figures 3 and 12. This step may be performed by a die, such as is disclosed'in Figure 20, to be described below.

The third and most important step in the method comprises continuing and substantially closing the already partially formed roll or bead entirely around the circumference of the cap skirt, except at certain spaced points, where the roll is not continued but is left open and is merely bent radially inwardly to form radial enlargements, which are subsequently shaped into looking lugs. The blank after this step has been performed is disclosed in Figures 4, 13, and 14, and .the die which performs the step is disclosed in Figures 21, 22 and 23, and will be described below. The lug formingprojections 31 have their outer surfaces 38 disposed on an inclined plane, and extend axially outwardly beyond the adjacent curled portions 28. Since-the rolled edge 36 of Figure 3 was not curled up at the lug portions, the edge 36 extends radially inwardly a substantial distance.

The final step in the method comprises bending the incipient lugs 31 into the interior of the cap shell, causing the several surfaces of the lugs to assume a predetermined position, and imparting a. slight additional roll to the intermediate bead portions 28. After this step has been completed the cap is finished and the bead portions are in the form of substantially closed tubular sections, as disclosed .in Figure 15, and the lugs are relatively uncuried, or'less curled, as disclosed in Figures 16 to 18 inclusive.-,

Figures 19 to 24 show various form of diesand associated apparatus parts adapted to perform the steps enumerated above.

In the apparatus of Figure 19, a stationary base block is provided with a socket in which is mounted a nest 5|, supported by a springpressed plunger 52 Above the block, a die forming assembly is hung from a cross-head 54. This assembly comprises a cylindrical die 55 fixedly secured to the cross-head and having a forming groove 56 on its bottom face. Within a central bore in the die 55 is a rod 51 normally projected downwardly by compression spring 58. Upon the lower end of the rod is a clamping pad 59 which, as the parts descend, first comes in contact with the interior surface of the top 25 of the cap blank, to hold the blank in position. Surrounding the rod 51, in spaced relation thereto, and within the die member 55, is a depending sleeve 60 having its lower end provided with a rounded cam surface 6|. Surrounding the sleeve 6|], and also within the die 55, is an expanding collet 62 made up of a plurality of spring fingers integral with a ring 63. Each of the fingers adjacent its lower end is provided with an inner cam surface 64 positioned to be engaged by the surface 5| of sleeve 50. Each finger terminates at its lower end in an outwardly projecting head 65. A compression spring 65 is disposed between a shoulder on fingers 62 and the ring 63 and a flange on the upper end of sleeve 60 to maintain each head 65 in contact with the upper surface of pad 58.

When the die assembly descends the clamping pad 58 moves inside of the cap blank, and the pad holds the blank upon the nest. Because the spring 53 below the nest is of lighter tension than springs 66 and 58, the continued movement of the pad 59 depresses the nest and blank into the socket in block 50. Further downwardmove- 56 gives it a slight inward bend or nip. The

fingers 62 are useful in assuring that the bend is confined to an area closely adjacent the edge of the flange.

When the cross-head 54 is raised, the movement of the parts is substantially the reverse of that described above, and the blank is raised to a level substantially equal to the top of the block 50 from which position it may be moved to the next station. 7

Instead of using a spring pressed nest 5|, as disclosed in Figure 19, a one-piece stationary nest 5|, disclosed in Figure 24, may be used to advantage. With a two-part assembly such as is disclosed in Figure 19, a minute groove is necessarily present at the juncture between the movable member 5| and the block 50, and this groove results in the formation of a slight rib, or other disfiguring mark, on the exterior of the blank. When a one-piece construction is used, this difficulty is obviated.

As a substitute for the spring pressed blank ejecting means of Figure 19, the nest may be provided with a central bore to which is connected a compressed air pipe 5|". Thus, after the particular operation has been performed, a blast of air may be utilized to eject the blank with entirely satisfactory results.

In Figure the die structure at the next station is disclosed. In this case it is unnecessary to provide the expanding fingers for the inner surface of the flange. because the curling die 68 merely imparts a heading to the metal which has already been started in the right direction. This die 88 has a circular curling groove in its bottom face which has a substantially semi-circular bottom. It functions to inwardly turn the edge of the flange to a substantially semi-circular cross-sectional curve.

In Figures 21, 22 and 23, a die is disclosed which functions to further bead or curl certain portions of the edge of the blank, and to form incipient lugs at other portions. This die performs the important step in the method disclosed in Figures 4, l3 and 14.

The bottom face of the die is provided with four circumferentially aligned grooves 1|, each of which terminates at its ends in widened portions 12. The radially inner wall of each groove at the portions 12 is formed into' a smooth rounded shoulder 13. The grooves merge, at their ends, into circumferentially spaced cut-away portions 10, the bottom surfaces of which have no positive formingactlon upon the bead. The intermediate grooves have substantially semi-circular bottoms, as disclosed in Figure 23. A die constructed in substantially this manner operates upon a partially beaded cap shell to complete the bead along spaced sections and forms enlargements thereon at other points. When the die descends, the grooves 1| will continue the.

curling action started by die 68, but since the groove is interrupted at the points Ill, this curling action will not be continued around the entire circumference of the skirt. At the cut-outs 10 the bead will not be rolled up or curled further. However, the tendency to curl imparted to the bead by the die sections II will be transmitted through the material of the cap skirt to the portions received in the cut-outs In, with t by the die disclosed in Figure the result that the latter portions will be drawn and will bend radially inwardly, as disclosed in Figure 21. These portions of the edge extend radially inwardly beyond the adjacent bead portions, and form projections in the nature of incipient lugs. They are completed, and bent to final form during the next step of the method,

In the apparatus of Figure 24, expanding fin gers 62', similar to the corresponding elements shown in Figure 19, are used. In this case the heads 65 project outwardly under the inturned bead and under the inturned incipient lugs'and form an anvil surface which limits the inward axial bending imparted by the die 55" to the lugs. The bottom face of the die is provided with a continuous curling surface 15 having a rounded corner 16. 'The curve 16 between the. outer side wall of the groove and the bottom is uniform around the entire circumference, and imparts a uniformly rounded lower external edge to the cap skirt. Furthermore, it functions to curl the bead of the cap a little more, and bends the incipient lugs downwardly into contact with the members 65'. Thus, the bottom edge of the cap skirt is uniformly rounded, and all points thereon lie in a common plane. The distance between the top of the cap and the thread engaging surface of each lug is accurately determined by the upper surface of heads 65'.

An important feature of the method resides in the fact that it is unnecessary in any of the several steps to position the blank in any particular angular adjustment with respect to the dies. After the second step the blank is of uniform configuration around theentire circumference of the fourth step has a surface of constant cross sectional shape at all points around its circumference, and the angular position of the blank with respect to the die is immaterial, as each point on the surface of the groove is adapted to complete the intermediate tions. The cap of the present invention may be made by several alternative methods. For instance, it is quite feasible-to roll'an inwardly disposed bead, as disclosed in Figure 15, entirely aroundthe circumference of the skirt, and then unroll certain portions of the bead to form lugs of substantially the form shown in Figure 16. This unrolling action can be accomplished by inserting an expanding die such'as is shown at 80, Figure 25, into the blank, expanding a plurality of die surfaces outwardlyinto contact with the upper surface of the bead, positioning the lower external surface of the bead upon an anvil or curling die OI, and then applying force to the expanded die to uncurl the bead. The anvil should have a supporting surface which conforms closely to the exterior surface of the bead so as to prevent deformation of the lower edge of the cap skirt. The die surfaces could be of any desired conformation and could be given any desired movement, either to flatten or unroll the bead, and the necessary function would be performed in any event, if certain spaced portions of the bead were projected inwardly beyond the adjacent coiled portions.

As shown in Figure 25, the unrolling dies lll comprise bell crank levers having hooked ends 82 adapted to be projected under the partially. formed bead as shown in Figure 26. By imparting a slight rotary movement to a cam ring 83, or by any equivalent-means, the levers 80 may be oscillated about their pivoting axes 84 so that the hooked ends 82 are swung inwardly to uncurl bead portions or the lug porthe bead, as clearly shown in Figure 27. A flndie such as is shown in Figure 24 may be used, if desired, to impart a flnal set to the 1113s, as shown in Figure 28, but, in many cases, the use of such a die is unnecessary.

An apparatus similar to that disclosed in Figurea 25 to 27 maybe used to perform the other alternative method described above, that is, in which lugs are formed by simply refraining from curling certain portions of the bead as much as other portions are curled. In such a case, the die surfaces 82 are inserted under the partially formed bead as shown in Figure 26, and the continued curling action of the curlingdie 8i will cause the partially formed bead to beprojected inwardly, since it cannot continue to curl at the points where the hooked ends are inserted. In

such a case, the ends 32 may be removed after the lug is formed by the manner shown in Figure 27, or by any other appropriate relative movement.

As an alternative method, a particular shape or contour may be given to the lugs by appropriate dies before the lugs are turned inwardly, as disclosed in the aforementioned copending application of Edward M. Enkur, Serial No. 660,927, flled March 15, 1933.

It'should be distinctly understood that the present invention is not limited to the details of the a consideration of the present disclosure. Consequently the invention must be given a scope commensurate with the present contribution to the art, and should be limited only to the methods 1 circumferentially spaced portions,

and articles described in the accompanying claims, and their equivalents.

This application is a division of the prior joint application flled in the name of Eric B. Kramer and Edward M. Enkur, Serial No. 657,734. flled February 20, 1933, which has resulted in Patent No. 2,231,190, Feb. 11, 1941. That application is directed to the article of manufacture disclosed therein, whereas the present divisional application covers the method of making the same.

I claim:

1. The method of making a closure cap from a blank having a top and a substantially cylindrical flange terminating in a free edge, which comprises the steps of'curling the free edge of the flange inwardly to. form a partial bead around the entire circumference ofthe flange, continuing the curling of the partial bead to substantially complete the saine entirely around the circumference except at circumferentially spaced portions, turning the partially formed bead at said spaced portions radiallyinwardly to form projections, and bending the projections toward the top of the cap to form upwardly and inwardly inclined lugs. v

2. The method of makinga closure cap from a bank having a top and a substantially cylindrical flange terminating in a free edge, which comprises the steps of curling the free edge of the flange inwardly to form a partial bead around the entire circumference of the flange, continuing the curling of the partial head to substantially complete the same entirely around the circumference except at circumferentiaily spaced portions, turning the partially formed bead at said spaced portions radially inwardly. without closing the partial bead to form projections, and bending the projections toward the top of the cap to form upwardly and inwardly inclined lugs.

3. The method of making a closure cap from a blank having a. top and a substantially cy-. lindrical flange terminating in a free edge, which comprises the steps of curling the free edge of the flangev inwardly to form a partial bead around the entire circumference of the flange, continuing the curling of the partial head to substantially complete the same entirely around the circumference except at circumferentially spaced portions, simultaneously turning the partially formed bead at' said spaced portions radially inwardly to formprojections, and bending the projections toward the top of the cap to form upwardly and inwardly inclined lugs.

4. The method of making a closure cap from a blank having a top and a substantially cylindrical flange, comprising the steps 'of curling the raw edge of the flange inwardly to form a concealed edge around the entire circumference of the flange, continuing the curling of the flange to form a substantially-tubular bead around the circumference of the flange except at circumfertively uncurled portions radially inwardly beyond the substantially tubular bead portions to form locking lugs.

5. The method of making a closure cap from I a blank having a top and a substantially cylindrical flange, comprising the steps of curling the raw edge of the flange inwardly to form a concealed edge around the entire circumference of the flange, continuing the curling of the flange to form a substantially tubular internal bead around the circumference of the flange except at leaving said spaced portions relatively uncurled, and simultaneously turning the relatively uncurled portions radially inwardly beyond the substantially tubular bead portions to form locking lugs.

6. The method of internally beading the depending skirt of a cap blank and forming inwardly projecting enlargements on the bead adapted to act as locking lugs for the cap, which comprises curling the edge of the skirt inwardly entirely around the periphery thereof except at circumferentially spaced points to form a bead and leaving the edge relatively uncurled at saidspaced points, bending the uncurled edge portions radially inwardly beyond the curled bead portions, and then horizontally aligning all portions of the edge, said relatively uncurled edge portions constituting enlargements on the bead.

7. The method of internally beading the depending skirt of a cap blank and forming inwardly projecting enlargements on the bead adapted to act as looking lugs for the cap, which coming horizontally said uncurled portions with said curled portions, the former constituting enlarges ments on the bead.

8. The method of making a closure cap from a blank having a top and a substantially cylindrical flange terminating in a free edge, which comprises bending a narrow marginal portion of the flange adjacent the free edge thereof radially inwardly to facilitate subsequent inward curling, then curling the free edge of the flange inwardly to form a partial head around the entire circumference of the flange, continuing the curling of the partial bead to form a substantially complete bead entirely around the circumference, exceptat circumferentially spaced portions, turning the partially formed bead at said spaced portions radially inward toform-projections, and bending the projections toward the top of the cap to form upwardly and inwardly inclined lugs.

9. The method of making a closure cap from a blank having a top and a substantially cylindrical flange terminating in a free edge, which comprises the steps of curling the free edge of the flange inwardly to form at least a partial bead around the circumference of the flange, further curling the flange entirely afound the circumference thereof, except at circumferentially spaced, relatively uncurled portions, and simultaneously drawing said relatively uncurled portions radially inwardly by said further curling of the flange along the adjacent portions. said inwardly drawn, relatively uncurled portions of the flange forming locking lugs.

10. The method of making closure caps from a blank having a top and a substantially cylindrical flange terminating in a raw edge, which comprises the steps of curling the lower end of the flange inwardly to form 0. turned edge entirely around the blank concealing said raw edge, further curling the flange inwardly to, provide a bead around the blank, projecting circumferentially spaced portions of the bead inwardly beyond adjacent intermediate portions to provide spaced inwardly projecting locking lugs, and disposing said turned edge of the flange at the lugs in position to present a rounded, reinforced thread engaging surface for cooperation with the threads of anassociated receptacle.

11. The method of making closure caps from a blank having a top and a substantially cylindrical flange terminating in a raw edge, which comprises the steps of curling the lower end of the flange inwardly to form a turned edge entirely around theblank concealing said raw edge, further curling the flange inwardly to provide a bead, uncurling circumferentially spaced portions of the bead without disturbing'said turned edge and thereby projecting portions of the bead inwardly beyond adjacent intermediate portions to provide spaced inwardly projecting locking lugs, and disposing the turned edge of the flange at .the lugs in position to present a rounded, reinforced thread engaging surface for cooperation with the threads of an associated receptacle.

12 The method of making closure caps from a blank having a top and a substantially cylindrical flange terminating in a raw edge, which comprises the steps of turning the raw edge inwardly entirely around the circumference of the skirt to provide a'rounded, reinforced edge, rolling the turned "edge of the skirt inwardly to provide a bead, projecting spaced portions of the inwardly rolled bead radially inwardly beyond adjacent, intermediate portions, and positioning the turned edgeof the flange at the inwardly projected portions so as to present a "rounded, reinforced, turned surface for cooperation with the thread or lug onan associated receptacle.

' 13. The method of making closure caps from a blank having a top'and a substantially cylindrical'flange terminating in a raw edge which comprises the steps of turning the raw edge inwardly entirely around the skirt to provide a bead concealing the raw edge, curling the flange and the turned edge inwardly entirely around the flange except at spaced points, restraining the inward curling of the flange and the turned edge at said points and thereby projecting the turned edge inwardly at said points to provide. rounded, reinforced cal flange terminating in a raw edge, which comprises the steps of turning the lower end of the flange inwardly to form a turned edge entirely around the blank concealing said raw edge, curling the turned edge and the flange adjacent thereto inwardly entirely-around the skirt to provide a bead, uncurling circumferentially spaced portions of thebead without disturbing the form of said turned edge to provide enlargements in the bead adapted to act as locking lugs, and positioning the turned edge of the flange at said enlargements so as to present rounded, reinforced thread engaging surfaces for cooperation with the threads of an associated receptacle.

15. An apparatus for forming metal caps including a die having an annular groove to curl inwardly the edge of a cup-shaped blank to form an in-curled bead,- said annular groove having cut-out portions at intervals in its inner wall only to permit portions of the blank to be drawn inwardly to form lugs.

16. An apparatus for forming metal caps including a die having an annular groove of substantially semi-circular cross-section to curl inwardly the edge of a cup-shaped blank to form an in-curled bead, said semi-circular groove havinga continuous wall, and having'its inner wall cut away at intervals, to permit portions of. the

blank to be drawn inwardly to form lugs.

17. The method of forming a metal cap from a cup-shaped blank which comprises curling an inside bead on the skirt by the pressure of a die, 4 i and causing spaced portion of the inwardly curling bead to draw inwardly adjacent portions of the bead to form lugs.

18. The method of forming a metal cap from a cup-shaped blank which comprises curling 'inwardly certain portions of the skirt by the pressure of a die and, by these curling-in portions, dragging inwardly lagging portions of the bead to form lugs. r

19. The method of forming a metal cap from a cup-shaped blank which comprises the forming of inwardly extending lugs at intervals by curling inwardly other portions of the blank skirt.

20. The method of forming a metal cap from a cup-shaped blank'which comprises the forming of inwardly extending lugs at intervals without the direct application of pressure thereto by directly applying pressure to other portionsof theblank skirt axially thereof to form an incurled bead at said portions.

21. The method of forming a metal cap which comprises engaging a die with the edge of the skirt of a cup-shaped blank and causing said 'edge tobe curled inwardly, and then further curling portions of the skirt to cause said edge of other portions of the skirt to be dragged inwardly to form lugs.

22. The method of forming a metal cap which comprises providing a turned edge around the skirt of a cup-shaped blank, engaging adie with said turned edge and causing the same to be curled inwardly, and then further curling portions of the skirt to cause the turned edge of other portions of the skirt to be dragged inwardly to form lugs. r

23. The method of forming a metal cap which comprises curling inwardly the skirt of a cupshaped blank and by this inward curling, causing the edge of certain portions of the skirt to be dragged inwardly to form lugs.

24. An apparatus for forming metal caps including a die having means for engaging and inwardly curling the edge of the skirt of a cupshaped blank, and means on said die causing portions of the skirt to be drawn inwardly from positions within the boundary of the skirt by the in-curling bead to form lugs.

25. An apparatus for forming metal caps in-. cluding a die having means for exerting direct pressure'against portions of the edge of a. cupshaped blank to inwardly curl the edge of "the blank, the die being cut away at other portions, thereby permitting the edge of the blank at these points to be freely drawn inwardly to form lugs, and means for determining the angle the lugs assume with respect tothe skirt of the cap.

26. An apparatus for forming metal caps, comprising a die, means on said die for curling inwardly the edge of a cup-shaped blank, and other means on the die for causing portions of the blank to be dragged inwardly, to form lugs.

'27. An apparatus for forming metal caps, oomprising a die, means on said diefor forming an' in-curl'ed bead on a cup-shaped blank, and means for causing portions of the edge "of the blankto be dragged inwardly to form lugs.

*28-:-An apparatus for forming metal caps including means for forming an'in-curled bead onv a cup-shaped blank, and means for causing portions of the edge of the blank to be. dragged inwardly to form lugs.

29. The method of forming a metal cap which comprises exerting pressure on the edge of the skirt of a cup-shaped blank to give, at least a partial inward curl throughout the edge, and relieving the curling pressure at certain spaced points only, to form lugs at those points.

30. The method of forming an interior bead and a projecting thread-engaging lug on a cap closure flange, which consists in bending the rim portion of the flange inwardly into the interior of the closure in proximity to the inner face of the flange, continuing the bending of the inbent portion until it assumes the form of a curled:

bead, and while continuing the bending applying a retarding forceto a segment of the inbent portion by means at the underside thereof to give the retarded segment the form of a resilient thread-engaging lug incorporated in the bead.

31. In apparatus of the character described, means for retaining a cap closure having an annular flange, a movable die member for inwardly bending the rim portion of the annular flange and shaped to form the inbent portion into a bead lying adjacent the inner face of the flange, an anvil movable within the outline of the flange into a position to be engagedby a segment of the rim portion, said die member having cooperation with the anvil concurrently with the shaping of the bead to press the segment into a projecting lug 'the proximateends of which are integrally connected with the head.

32. The method of fabricating a thread-engaging type 'of cap closure having a' cylindrical flange with a bottom rim edge of uniform extent from the crown of the closure, whichv con- 'sists in bending under die control, without altering the outer face of the flange, a uniform amount versely rounded inwardly directed rim edge portion and also a marginal interior portion, both extending circumferentially around the flange and the marginal interior portion terminating above the plane of the lowermost surface of the transversely rounded rim edge portion, and in bending under die control the marginal interior portion into beads and lugs alternating in the circumferential direction of the flange, the beads being curled outwardly toward the inner face of 'the flange in substantially symmetrical rounded relation with the transversely rounded rim edge portion and the lugs being bent in an inward direction and, shaped into effective thread-engaging form.

33. The method of forming an interior locking projection on 'a cap closure flange of cylindrical form, which consists in subjecting a uniform portion of the entire circumferential lower edge of the flange to inward bending and curling pressure so as to produce an inwardly curled supporting-bead having a constant cross sectional convex surface curve continuously around the inner periphery of the flange, and substantially concurrently'subjecting adeflnite segment of the material from which the supporting curled bead is being produced to alesser bending and curling pressure until. an interior locking projection is obtained which has its base and ends integral with the supporting bead.

34. The method of forming interior locking projections on a' cap-closure flange of cylindrical form, which consistsin convexly curling inwardly a uniform portion of the entire circumferential lower edge of the flange to produce inwardly of the flange a convexly curled supporting base having beyond it a continuous marginal section. continuing to curl the marginal section to complete a curled bead around "he entire inner periphery of the flange, and wnile continuing the curling to complete the curled bead, subjecting segments of the marginal section at thereof simultaneously by a plurality of members which shape the incurled metal into container engaging lugs, and thereafter simultaneously withdrawing said members.

38. The method of making a closure cap from a blank having a top and a substantially cylinspaced points to bending and shaping pressure until such segments assume between the adjacent sections of the curled bead, the form of locking projections which project inwardly beyond the adjacent segments of the curled bead.

35. The method of forming interior beads and looking projections on a cap closure flange of stantially the innermost portion of the supporting rim edge to bending pressure until locking projections of the desired shape and projection are obtained.

36. Apparatus of the kind described, having, in combination, a movable die member and a movable anvil member, the die member being shaped forinwardly upsetting the entire cylindrical edge portion of a cylindrical flange to form a curled bead with a substantially constant cross sectional curve around the entire inner periphery of the flange, the die member and anvil member having arrangement and operation so that as the curled head is produced by the die member the anvil member will cooperate with the die member to press out and shape from a segment of the material being upset, a locking projection which is supported by the curled bead, and said anvil member being effective to dispose the locking projection in a position in which it projects inwardly beyond the curving surface of the adjacent segments of the curled bead.

37. In a method of forming-a metal closure, the steps which comprise curling inwardly the blank skirt throughout the entire circumference thereof to form a circumferential bent in portion. and after the metal has been curled inwardly to the desired extent, engaging spaced portions .a free edge.

drical flange terminating in a free edge, which comprises the steps of curling the free edge of the flange radially inwardly to form abead, partially uncurling circumferentially spaced portions of the bead, and thereby projecting the relatively uncurled portions radially inwardly beyond the adjacent curled bead portions to form locking lugs for said closure cap.

39.'The method of making a closure cap from a blank having a top and a substantially cylindrical flange terminating in a free edge, which comprises the steps of curling the free edge of the flange radially inwardly to form a bead, partially uncurling circumferentially spaced portions of the bead, while maintaining other portions in their curled condition, and thereby projecting the relatively uncurled portions radially inwardly beyond the adjacent curled bead portions to form locking lugs for said closure cap.

40. The method of producing a thread-engaging lug on the metallic annular flange of a cap closure, which consists in inwardly inbending, without deforming the outer face of the flange, the rim portion of the flange, maintaining a pressure for curling the rim portion upon itself to produce a resilient open bead at the inside face of the flange, and concurrently pressing a segment of the inwardly bent rim portion to produce aresilient projecting lug having communicating resiliency with the curled bead at either side thereof.

41. In an apparatus of the character described. means for retaining a cap closure having an annular flange, a movable die member having a groove for inwardly bending the rim portion of the annular flange to produce on the flange an inwardly rounded rim edge, said groove being shaped to press the inwardly bent material fol-' lowing the rounded rim edge. into a head of the desired configuration, an anvil within the outline of the flange for engaging a segment of the inwardly bent material at a point beyond a the rounded rim edge, said groove cooperating with the anvil to press the engaged segment intoa projecting lug beginning at the proximate termination of the rounded rim edge and ending in EDWARD M. ENKUR.

Images