US3438348A - Method and apparatus for producing lug type closure caps - Google Patents

Description

April 15, 1969 A. 1.. MEROLLE METHOD AND APPARATUS FOR PRC )DUCING LUG TYPE CLOSURE CAPS She et Filed Oct. 12, 1966 INVENTOR. #06057; A. M51011:

3,438,348 METHOD AND APPARATUS FOR PRODUCING LUG TYPE CLOSURE CAPS FiledOct. 12,1966

April 15, 1969 A. L. MEIROLLE April 15, 1969 A. L. MEROLLE 3, v

METHOD AND APPARATUS FOR PRODUCING LUG TYPE CLOSURE CAPS Sheet Z of 6 Filed Oct. 12, 1966 N I N A. L- MEROLLE April 15, 1969 J METHOD AND APPARATUS FORPRODUCING LUG TYPE CLOSURE GAPS Filed Oct. 12, 1966 Sheeh NNE ' INVEN '1 OR.

April 15, 1969 A. MEROLLE 3,433,346

METHOD AND APPARATUS FOR PRODUCING LUG TYPE CLOSURE GAPS Filed Oct. 12. 1966 April 15, 1969 A. MEROLLE 3,433,343

METHOD AND APPARATUS FOR PRODUCING LUG TYPE CLOSURE CAPS Filed Oct. 12, 1966 Sheet 6 of s INVENTOR. AUGUSTUS 4. M59041:

United States Patent 3,438 348 METHOD AND APPARATUS FOR PRODUCING LUG TYPE CLOSURE CAPS Augustus L. Merolle, 1171 86th St., Brooklyn, NY. 11228 Filed Oct. 12, 1966, Ser. No. 586,200 Int. Cl. B21d 51/00, 53/00 U.S. Cl. 1131 8 Claims ABSTRACT OF THE DISCLOSURE Apparatus for producing metal closure caps includes holding means which engages a metal shell having a circular skirt which is essentially at a right angle to the circular base of the shell up to and including the raw edge portion of the skirt. The holding means engages the shell and continues to hold the shell during all the steps required to transform the shell into a finished closure cap having a liner disk. At a first station of the apparatus a liner disk is inserted into the shell. Thereafter a spinning device partially incurls the raw edge of the skirt to form a flange. In the next operation a die means partially incurls the flange. Thereafter another die means engages the partially incurled flange to form partial lugs and partial beads. Further die means then engages the partially formed lugs and beads to transform these elements into their final forms.

This invention relates to lug type closure caps in general and more particularly relates to novel apparatus and methods for producing lug type closure caps of high quality at a fast rate with minimal expense and space for production machinery.

The particular type of closure cap which is the subject of the instant invention is one having an inwardly turn head which is crushed at intermittent points to form lugs which engage the threads of a container for securing the closure cap over a container opening. A cap of this kind is shown in the US. Patent 2,297,643 issued Sept. 29, 1942 to J. J. Williams for a method of forming metallic closures.

In the method of the aforesaid Williams patent the raw edge of the skirt depending from the top of the shell is inturned in a single operation to provide a flange. This is typical of most prior art methods and results in an inferior product in that the stamping die for performing this operation applies excessive forces to the raw edge of the skirt forcing the skirt towards the top of the shell and in so doing causing unwanted displacement of metal to mar the appearance of the top. To overcome this, the prior art has utilized means for precurling the raw edge prior to engagement thereof by the flange forming die. However, this pre-forming has been done in apparatus separate from the lug forming machinery, with such separate apparatus often being very costly and slow operating. As will hereinafter be seen, the apparatus of the instant invention performs the pre-forming operation and the final forming of the inturned flange in the same machine that forms the lugs without slowly production speed.

Further, when separate apparatus is utilized for preforming it is necessary to insert liner disks into the shell after pre-forming and, of necessity, the disk diameter must be less than the shell top diameter resulting in a loose or floating fit between liner disk and cap. This is especially undesirable for those applications where the disk must be glued to the rim of the jar. Such an application is the multi-layer liner for the cap of a jar containing instant coflee. One of the liner layers is thin glassine which is glued to the very narrow rim of the jar by glue applied to the rim prior to mounting the cap, With multi-layer 3,438,348 Patented Apr. 15, 1969 liner disk, thereon. If the fit between cap and glassine disk is too loose the glassine disk may not contact the entire rim resulting in imperfect sealing. The apparatus of the instant invention is such that the liner is inserted into the shell prior to pre-forming so that there is relatively close fit between liner disk and shell.

After formation of the flange, incurling thereof takes place to form a bead and at the same time, spaced portions of the bead are formed into thread engaging lugs. It the prior art, formation of these lugs has been done with a single stamping die means operating at extremely high pressure. Such die means included fingers which movec' radially outward to support the lugs during formatior thereof. Because of the high pressures required for forming lugs in a single operation, these support fingers were subjected to excessive strain, and as a result frequently broke.

In order to overcome this disadvantage of the prior art the instant invention forms the thread engaging lug: in a two-step operation. That is, in a first step a die mean: engages the inturned flange to produce a partially former bead having spaced partially formed lugs. Thereafter, 2 different die means having radially movable suppor: fingers engages the partially formed bead and partiall) formed lugs to transform them into their final forms. B3 performing the lug forming operation in two steps rather than one, better control of lug size, and perhaps ever more important, better control of overall cap quality it obtained than it is possibleto obtain by using prior ar methods and/ or machinery.

The apparatus of the instant invention, to be hereinafter described, also includes means for cutting a paper liner and inserting same into the shell prior to performing any of the incurling and lug forming operations. A: will hereinafter be seen, the apparatus of the instant invention is such that once a blank is fed into the apparatus, such blank is securely held during, and is not released between, operations in which a liner is inserted therein, at inturned flange is formed in two separate operations and, in two additional operations, the inturned bead and thread engaging lugs are formed.

Accordingly, a primary object of the instant invention is to provide novel means and methods for the productior of lug type closure caps.

Another object is to provide a method of this type it which the lugs are pre-formed prior to final formatior thereof, thereby resulting in a product of superior quality.

Still another object is to provide lug cap forming apparatus in which formation of the inturned flange is a twostep operation performed without releasing the shell between steps.

A further object is to provide apparatus of this type having means for forming and inserting a liner into the shell prior to commencing formation of the flange, beac' and/ or lugs.

A still further object is to provide novel apparatus in which a work holding means engages a shell with 2 straight skirt and does not release such shell until after it is transformed into a finished lug cap.

These as well as other objects of this invention will become readily apparent after reading the following description of the accompanying drawings in which:

FIGURE 1 is a perspective illustrating cap forming apparatus constructed in accordance with the teachings 01 the instant invention.

FIGURE 2 is a plan view of the appartus in FIGURE 1.

FIGURE 2A is a fragmentary plan view of the intermittent drive mechanism.

FIGURE 3 is a cross-section taken through the line 3-3 of FIGURE 2 looking in the direction of arrows 33.

FIGURE 4 is a vertical cross-section taken through the liner cutting and inserting head with this head shown raised to non-working position.

FIGURE 5 is a vertical cross-section taken through the pro-curling head with this head shown lowered to working position.

FIGURE 5A is a bottom view showing the mounting of the spinning wheels in the head of FIGURE 5.

FIGURE 6 is a vertical cross-section taken through the flange forming head with this head shown raised to non-working position.

FIGURE 7 is a vertical cross-section taken through the head which partially forms the bead and lugs with this head shown raised to non-Working position.

FIGURE 8 is a vertical cross-section taken through the head which finishes the bead and lugs with this head shown raised to non-working position.

FIGURE 9 is a perspective of a finished lug cap.

FIGURE 10 is a bottom view of the cap of FIGURE 9.

FIGURES 11 through are diametric cross-sections showing the cap of FIGURE 9 during various stages of its production. FIGURE 11 shows the shell or cap blank which is fed through the apparatus of FIGURE 1 and FIGURE 12 shows this blank after the pre-curling operation. In FIGURE 13 the flange is formed, in FIGURE 14 the bead and lugs are partially formed and in FIGURE 15 the bead and lugs are shown in finished form. It is noted that if the lug cap being produced is to have a liner disk, such disk 31 (shown phantomed in FIGURE 12) is inserted into the shell prior to formation of the pre-curl.

Now referring to the figures and more particularly to FIGURES 9 through 15 which illustrate the various stages of production for a lug type cap produced by utilizing the novel process and apparatus constituting the instant invention. More particularly, shell 22 (FIGURE 11), produced by means forming no part of the instant invention, is fed to the appartus of FIGURE 1, to be hereinafter described, and is transformed thereby into lug cap 20 (FIGURE 15).

Shell 22 includes circular top 23 and cylindrical straight walled skirt 24 extending from top 23 along the periphery thereof. Initially, inward pre-curl 25 (FIGURE 12) is formed along the free edge of skirt 24 by the spinning means of FIGURE 5. Next, the die means of FIGURE 6 engages the incurl 25 forcing it further inward and somewhat downward to form flange 26 (FIGURE 13). Thereafter, the die means of FIGURE 7 engages flange 26 to form partial bead 27 having four partially formed lugs 28. Finally, the die means of FIGURE 8 engages the partially formed bead 27 and partially formed lugs 28 to form the final bead 29 and final lugs 30. The shape of pre-curl 25 contributes significantly to the sizes and shapes of bead 29 and lugs 30. If cap 20 is to be provided with a disk type liner, such as paper disk 31 shown in phantom in FIGURE 12, disk 31 is inserted into shell 22 prior to the spinning of incurl 25.

As will hereinafter be seen, after shell 22 is fed into a holding means of the apparatus of FIGURE 1, such holding means does not release shell 22 until production of cap 20 is completed.

Now referring more particularly to FIGURES 1 through 8 which illustrate the apparatus for producing cap 20. Such apparatus includes stationary frame section 35 supporting the movable members of the apparatus. Fixed hollow vertical main post 36 extends upwardly above table portion 35a of frame 35. Spider 37 is mounted to the upper end of internal post 38 slideably mounted inside of main post 36. Nut 39 threadably engaged with the reduced diameter threaded part at the upper end of internal post 38 secures spider 37 to post 38. Pin 41 pivotally connects the upper end of crank arm 42 to the lower end of post 38 while the lower end of crank arm 42 is provided with a circular aperture that receives a :ircular cam eccentrically mounted on main drive shaft 40. Thus, in a manner well known to the art, the rotational motion of shaft imparts a reciprocating motion to spider 37.

Gear 43 keyed to main drive shaft 40 drives gear 44 on counter shaft 45 with the latter gear 44 being in mesh with gear 46 keyed to shaft 47. Main drive shaft 40 is perpendicular to, and extends through, the longitudinal axis of center post 36. While shafts 40, 47 are parallel, the latter is remote from the longitudinal axis of center post 36. Keyed to shaft 47 is cam 48 (FIGURES 2A and 3) which engages rollers 49 mounted to stub shafts 50 extending radially from column 51 to rotate the latter about center post 36 on bearings 52, 53.

Cam 48 and rollers 49 cooperate to form a worm gear type drive in that cam 48 is formed as a thread which is modified in such a manner that the rotation of collar 51 takes place in rapid short angular steps with null or rest periods between each of these steps. For details of an intermittent drive mechanism of this type reference is made to catalog No. 160A of the Ferguson Machine Corporation of Ind, Roller Gear Division, St. Louis, Mo.

In the apparatus of FIGURES 1 through 8 the intermittent drive mechanism is provided with twelve rollers 49 which act as teeth of a spur gear cooperating with modified worm type cam gear 48 to rotate ring 55 through a complete revolution in twelve equal angular steps. Correspondingly, table 55 is provided with twelve cavities 56. During each of the twelve null periods for table 55 one of the cavities 56 is aligned with finger 61 which feeds cap shell 22 to table 55. At this time another of these cavities 56 is aligned with the liner disk cutting and insertion head 62 (FIGURE 4), another of these cavities 56 is positioned in alignment with incurling spinner head 64 ((FIGURE 5), another of these cavities S6 is positioned in alignment with flange forming head 66 (FIGURE 6), another of these cavities 56 is in alignment with die means 68 (FIGURE 7) which partially forms bead 27 and lugs 28, another of these cavities 56 is posi-' tioned in alignment with die means 70 (FIGURE 8) which forms the final bead 29 and final lugs 30, and another of these cavities 56 is empty just having had a finished cap 20 removed therefrom. The remaining cavities 56 are disposed between certain of those cavities 56 whose positions have heretofore been described in greater detail.

Ring-like horizontal work table 55 is positioned above stationary table 35a and is secured to the outside of sleeve 51 near the upper end thereof so as to be rotatable therewith. The upper surface of table 55 is provided with a plurality of circular cavities 56, 56 etc. each having a liner ring 57 along the side wall thereof and a base or support disk 58 resting against the bottom thereof. Tail piece 58a extends perpendicularly from the center of disk 58 downwardly through aperture 56a at the bottom of cavity 56 to project below table 55 for ejection of finished caps 20 in a manner to be hereinafter explained. A new ring 57 and disk 58 are placed in each cavity 56 for the production of different sizes of caps.

Spider 37 includes ring-like section 37a and arm 37b extending diametrically across ring 37a. The latter is provided with four radial extensions 370 each having an individual guide sleeve 71. Each sleeve 71 is closely fitted to an individual vertical guide post 72 extending upwardly from table 35a in an array having post 36 at the center thereof. The cooperation of sleeves 71 and posts 72 serves to stabilize spider 37 in its vertical reciprocating movement toward and away from table 37a. Heads 62, 66, 68, 70 are secured to spider 37 being spaced along ring portion 37a thereof (see FIGURE 2).

As seen in FIGURE 4, head 62 for producing and inserting liner disks 31 is provided with hollow vertical guide 81 fixedly mounted to horizontally extending member 82 positioned above table 55 and fixed to table 35a by standoff 83. Member 82 is provided with a circular aperture aligned with the opening through guide sleeve 81. Slit-like aperture 84 extending transversely through sleeve 81 provides a horizontal guide for paper ribbon 85 from which liner disks 31 (FIGURE 12) are made. Means 86 (FIGURE 2) feeds paper ribbon 85 with an intermittent motion through guide aperture 84 with power for driving means 86 being taken from countershaft 45 by eccentric 86a (FIGURE 3) and applied to arm 87 by a coupling device (not shown).

Head 62 further includes guide member 91 depending from spider 37 and having an outer cylindrical surface closely fitted to the interior wall of sleeve 81. Vertically movable circular knife 88 is mounted to member 91 at the bottom thereof by screws 88a and cooperates with stationary knife 89 below ribbon 85 to cut disk 31 from ribbon 85 upon downward movement of spider 37.

Stripper 90 is mounted inside of movable knife 88 and is mounted for limited movement with respect thereto. More particularly, knife 88 is mounted to the lower end of stem 90a which extends upwardly through a closely fitted bore in knife member 88 and an enlarged central bore 91a of member 91. Compression spring 92 bears against the upper end of knife member 88 and collar 93 surrounding stem 90a. Spring clip retainer 90b mounted in a groove of stem 90a limits upward movement of collar 93.

The upper end of member 91 is provided with slot 93a open at one end to receive flange 99a at the lower end of guide sleeve 99. The outer surface of sleeve 99 above flange 99a is threaded and extends through the threaded bore of sleeve 98 and is engaged by lock nuts 98a. Sleeve 98 extends downwardly through an aperture in spider 37. The upper end of stem 90a extends into the vertical bore of sleeve 99 and supports the lower end of push rod 97 extending into such bore through its upper end.

As seen in FIGURE 1, the upper end of rod 97 is provided with yoke 98 at its upper end. Compression spring 96 surrounds rod 97 biasing the latter upward with upward movement being limited by engagement of yoke 98 with the upper end of bracket 95 fixedly secured at its upper end to spider 37.

Yoke 98 is pivotally connected to one end of swivel bar 94 pivotally connected at pin 94a to clevis 94b at the upper end of rod 940 projecting upward from spider 37. The portion of bar 94 to the left of pin 94a as viewed in FIGURE 1 engages fixed adjustable stop 93 at the upper end of post 36 as spider 37 moves down. This engagement between bar 97 and pin 93 causes the former to pivot clockwise about pin 9411 with respect to FIGURE 1 and in so doing drives rod 97 downward more rapidly than spider 37 with this difference in speed being magnified by placing pivot pin 94b very close to the left end of swivel bar 94.

When spider 37 descends movable knife 88 engages paper web 85 and in cooperation with stationary knife 89 cuts paper liner disk 31 which falls to the bottom of the aperture in member 82 being stopped by inward taper 82a. Downward movement of knife 88 stops considerably short of shell 22. However, after liner disk 31 is cut, swivel bar 94 acting through rod 97 moves pusher 90 below knife 88 picking up liner disk 31 and forcing it against the top wall 23 of shell 22.

It is noted that for clarity of illustration, liner disk 31 is not illustrated in many of the figures. For many applications lug caps are not provided with liner disks, but are provided with an internal sealing ring formed by the application of a liquid which solidifies into a deformable material. Such ring is applied to the cap subsequent to formation of the final bead and final lugs.

Spinning head 64 of FIGURE 5 for producing inward pre-curl 25 includes generally bell-shaped member 101 fixedly secured to the lower end of vertical tube 102 which extends through spider 37 being rotatably supported thereon by bearings 103, 104. Pulley 105 is keyed to tube 102 and is positioned above spider 37. Flexible belt 106 (FIGURE 2) provides a driving connection to pulley 105 from pulley 107 driven by electric motor 108 mounted to bracket 109 afiixed to and movable with spider 37. The flared portion at the bottom of member 101 carries at least one and preferably a plurality of stub shafts 110 (in this case three) which extend radially inward and are equally spaced from one another. Freely mounted on the inner end of each of the stub shafts 110 is an individual spinning wheel 111 having an appropriately shaped depression 112 in the periphery thereof to receive the free edge of skirt 24 and roll therealong as downward pressure is applied and in so doing form precurl 25.

Spinning head 64 includes clamping member 114 which engages the inner surface of top wall 23 to prevent rotation of shell 22 upon the engagement by spinning wheels 111. Member 114 is mounted to the lower end of shaft 115 which extends longitudinally through tube 102. The threaded reduced diameter upper end 115a carries stop washer 116 and fastening nut 117. Coil compression spring 118 is mounted on the lower end of shaft 115 having one end bearing against member 114 and the other end bearing against the frame of thrust bearing unit 119 forcing the latter upward against the lower end of tube 102.

During operation of the cap forming apparatus, motor 108 is in continuous operation so that tube 102 rotates continuously about its longitudinal axis in turn rotating member 101. With spider 37 in its upper-most position, clamping member 114 is positioned above pre-curl 25. As spider 37 descends clamping member 114 engages top wall 23 and as spider 37 continues to descend spring 118 is compressed to increase the force exerted by clamping member 114 against top wall 23. Continued downward movement of spider 37 brings the free end of skirt 24 into peripheral depressions 112 of spinning wheels 111. Spinning Wheels 111 being freely mounted on shafts 110 rotate along the free edge of skirt 24 with the downward pressure exerted by spinning wheels 111 on skirt 24 and the contour of depression 112 forming pre-curl 25.

Flange forming head 66 of FIGURE 6 includes disklike inner die part 131 slideably mounted inside of ringshaped outer die part 132. Part 132 is fixedly mounted to member 133 by screws 134 with member 133 being threadably secured to the lower ends of shaft 135. The latter extends parallel to center post 36 and through spider 37 being fixedly secured thereto by nuts 136, 137 in conjunction with washer 138 adjacent to nut 137 and sleeve 139 having a flange adjacent to nut 136. Screw 140, axially aligned with shaft 135, connects inner die part 131 to member 133 for limited movement with respect thereto in a direction along the axis of shaft 135. A plurality of compression springs 141, interposed between die part 131 and member 133, bias die part 131 downward with respect to member 133.

In operation, as spider 37 descends inner die part 131 engages liner disk 31 and movement of part 131 is stopped. However, spider 37 continues to move downward carrying outer die member 132 downward. The angular notch 142 in part 132 adjacent to the periphery of part 131 receives incurl 25 forcing the latter inward to form flange 26 having a downturned edge (FIGURE 13). Inward movement of incurl 25 during formation of flange 26 is limited by the peripheral edge of inner die part 131.

Head 6-8 for the formation of partial bead 27 and partial lugs 28 includes movable inner and outer die parts 151, 152, respectively. Post for the support of die parts 151, 152 is mounted to spider 37 in the same manner as post 135. In addition, the mounting of die parts 151, 152 to post 150 is the same as the mounting of die parts 131, 132 to post 135. Outer die part 152 is provided with continuous angular depression 153 adjacent to the peripheral edge of inner die part 151. Depression 153 is deeper at four equally spaced portions 154 thereof. When spider 37 is lowered outer die part 152 engages flange 26, the configuration of relatively shallow depression 153 for the major portion of its length produces partially formed bead 27 and the relatively deeper portions 154 produce partially formed lugs 28.

Head 70, FIGURE 8, for final lug and bead forming includes inner die part 161 and outer die part 162. The former is mounted to the lower end of rod 163 extending through a longitudinal bore of post 164 fixedly secured to spider 37. Nut 165 mounted to the upper end of rod 163 engages the upper end of post 164 to limit downward movement of rod 163 threadably mounted to inner die part 161. Positioned along the axis of rod 163 is ejector means 166 including pin 167 biased downwardly by compression spring 168. Screws 169 fixedly mount outer die part 162 to member 171 in spaced relation with spacer member 172 interposed therebetween.

Compression springs 173 engaging the lower portion of member 171 bear against the out-turned flange at the upper end of sleeve 174 surrounding the enlarged lower end of rod 163. Downward movement of sleeve 174 is limited by the engagement of this flange with an inboard shoulder of spacing ring 172. The lower outboard edge of sleeve 174 is inclined and is engageable with inclined surfaces at the inboard side of flanges 175 to cooperate therewith in moving the lower ends of these fingers outwardly about their respective pivots 176, for a reason to be hereinafter explained. Pivots 176 are mounted to member 161a which is a section of inner die part 161. With head 170 of FIGURE 8 in the raised or inactive position shown, fingers 175 are disposed entirely within appropriate recesses in element 161a.

In operation as spider 37 is lowered die part 161a is the first to engage the partially formed cap. When downward movement of inner die part 161a is arrested part 174 continues to move downward with the inclined surface portion thereof engaging camming Surfaces 175a of fingers 175 forcing finger tips 175b to pivot outwardly about pins 176 as centers. There is an individual finger 175 for each of the partially formed lugs 28. When finger tips 17512 are moved outwardly by the camming action described, tips 175]) are positioned below partially formed lugs 28. Continued movement of spider 37 in a downward direction brings outer die part 162 into engagement with partially formed bead 27 and partially formed lugs and in so doing transforming these elements into final bead 29 and final lugs 30, respectively. During this operation finger tips 17512 provide support from below for lugs 30.

For an overall description of machine operation, particular reference is made to FIGURES 1 and 2. Upper horizontal flight 201 of a continuous belt conveyor moving in the direction indicated by arrow A in FIGURE 2 delivers shells 22 and removes caps 20. That is, upper flight 201 is positioned just below trnasverse barrier 202 which extends over table 55. The reciprocating motion of feeding finger 61 is coordinated with the intermittent motion of table 55 in a manner such that finger 61 moves forward, or in the direction of arrow B of FIGURE 2, for each stopping, or rest period for table 55. In moving forward finger 61 drives the shell 22 adjacent to barrier 202 on to table 55 and into a holding cavity 56 thereof aligned at that time with the longitudinal axis of fingers 61. Pusher 300 (FIGURE 1) extending downward from spider 37 firmly seats each shells 22 in the bottom of a cavity 56.

After a shell 22 is moved into a holding cavity 56 of table 55 the latter is moved through a succession of thirty degree angular steps. After two such steps this shell 22 is positioned in alignment with head 62 for cutting liner disk 31 and inserting same into shell 22. After the fourth step this shell 22 is in alignment with the pre-curl forming spinner head 64. After the sixth step, this shell 22 is in alignment with flange forming head 66. After the eighth step, this shell 22 is in alignment with head 68 for pre-forming the bead and lugs. After the tenth step, the partially formed cap is in alignment with head 70 which performs the final cap forming operation.

As table 55 moves between its eleventh and twelfth steps, finished cap 20 is first lifted upwardly out of its holding cavity 56 and thereafter is directed on to the upper flight 201 of the conveyor belt. That is, in moving between the eleventh and twelfth steps, ball bearing 58b projecting from the lower tip of tail piece 58a rides upwardly on stationary incline 204- and in so doing raises base 58 to a position where cap 20 is slightly above the upper surface of table 55. Base 58 remains in this raised position so long as bearing 58b remains in engagement with the raised horizontal portion 205 at the upper end of incline 204. With cap 20 in this raised position and table 55 in motion, cap 20 is engaged by the curved surface at the left of removal finger 207 and the reaction force causes this cap 20 to move in the path indicated by curved arrow C thereby leaving table 55 and moving to that portion conveyor belt flight 201 to the left of finger 207.

Thus, it is seen that the instant invention provides novel processes and apparatus for the production of lug type caps. In particular, the cap is formed from a shell which is fed to the apparatus, is engaged by a holding means and is not released from such holding means until the bead and lugs are in final form. Cap quality is improved by dividing a number of operations into multistep operations rather than single step operations. For example, the bead and lugs are partially formed in one operation and in a separate operation the bead and lugs are worked into final form.

It is also noted that even though formation of a lug cap with a liner can be produced in accordance with the teachings of the instant invention by utilizing a conveyor ring which completes a revolution in only six steps, higher speed production without loss of quality is obtained by using a twelve step complete revolution for the conveyor ring. That is, the small steps for the conveyor ring are a function of the diameter of the cap and the diameter of the conveyor ring. It is desired to have the conveyor ring as small in size as possible but cap size cannot be controlled so that apparatus must be made large enough to produce the largest size cap likely to be required. Secondarily, the sizes of the various operating heads 62, 64, 66, 68, 70 dictate a certain minimal spacing. It has been found that this minimum space is between one and two times the spacing required between the largest sizes of caps commonly produced. Thus, the spacing between the working heads is made two times the angular stepping distance of the conveyor ring. The use of a Ferguson Drive permits short rapid steps for table or ring conveyor 55 so that it is advantageous to feed a blank to table 55 for each step and to operate on a particular blank for alternate steps thereof. However, for each null period of the conveyor table the work head carrying spider moves downward so that these work heads perform a working operation during each null period.

Although there has been described a preferred embodiment of this novel invention, many variations and modifications will now be apparent to those skilled in the art. Therefore, this invention is to be limited, not by the specific disclosure herein, but only by the appending claims.

The embodiments of the invention in which an exclulsive privilege or property is claimed are defined as folows:

1. A method for producing a lug type closure cap from a metal shell having a circular top with a cylindrical skilt terminating in a raw edge; said method including the steps of partially incirling said skirt along said raw edge to form a flange by engaging the raw edge with a spinning device; thereafter operating on said flange with a stamping die means to transform spaced portions of the flange into partially formed container engaging lugs and additionally curling portions of said flange intermediate said partially formed lugs to transform said portions into partially formed bead sections; thereafter utilizing another means to shape said partially formed lugs and partially formed bead sections into their final forms thereby producing a closure cap.

2. A method as set forth in claim 1 in which the shell is engaged and held by a work holding means when said skirt, up to said ra-w edge, is essentially at right angles to said top, said work holding means continuing to hold said shell until after formation of said closure cap.

3. A method as set forth in claim 2 in which a liner disk is inserted into said shell after engagement by said work holding means and while said skirt, up to said raw edge, is essentially at right angles to said top.

4. Apparatus for producing a closure cap from a metal shell having a circular top with a cylindrical skirt terminating in a raw edge; said apparatus including a plurality of working heads; a shell holding means movable along a predetermined path into working alignment with each of said working heads; said working heads operable between inactive positions remote from said path to active positions for engaging and working upon shells held by said holding means; drive means coordinating movement of said holding means and said working heads in a manner such that said holding means is stopped as said working heads move toward said path and said holding means moves while said working heads are remote from said path; a first of said heads including means for pro-curling a shell skirt raw edge; a second of said heads including means for transforming a pre-curled shell skirt edge into a flange; a third of said heads including means for partially forming a bead and spaced lugs at a flange of a shell skirt; a fourth of said heads including means for transforming partially formed bead and lugs into final form.

5. Apparatus as set forth in claim 4 in which there is a movable frame section to which all of said working heads are mounted; means guiding said movable frame section for movement between a raised and a lowered position; said working heads being in said inactive positions when said movable frame section is in said raised position; said working heads being in said active positions when said movable frame section is in said lowered position.

6. Apparatus as set forth in claim 5 in which said means for pre-curling a shell skirt raw edge includes a spinning device and means for continuously driving said spinning device as said first working head moves from its said inactive to said active positions.

7. Apparatus as set forth in claim 5 in which there is a table to which said holding means is mounted; means mounting said table for rotation about a vertical axis; said working heads disposed above said table in a circular array about said axis; said drive means including worm gear and follower means mounted to said table in driving engagement with said worm; means defining a horizontal axis about which said worm gear is continuously rotated at uniform speed throughout each revolution; said worm gear having a modified thread to intermittently drive said table through said follower means in uniform angular steps with null periods between said steps.

8. Apparatus as set forth in claim 5 in which there is a table to which said holding means is mounted; means mounting said table for rotation about a vertical axis; said working heads disposed above said table in a circular array about said axis; said drive means intermittently operating said table in uniform angular steps with null periods between said steps; said working beads being spaced apart by distances such that said table moves through a plurality of said steps to move a section of said holding means between adjacent ones of said first, said second, said third and said fourth working beads.

References Cited UNITED STATES PATENTS RONALD D. GREFE, Primary Examiner.

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 3.438.348 Dated A r 15 1959 Imrent:or(s)A I Mgxgi], I

It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

Claim 1 column 8, line 67, change "incirling" to --incur11ng-- Sylgned and sealed this 1st day of September 1970.

(SEAL) Attest:

EDWARD M'.FLETCH'ER,JR.

Attesting Officer WILLIAM E. SCHUYLER, JR,

Commissioner of Patents

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