US3191422A - Method and apparatus for forming metal articles - Google Patents

Description

June 29, 1965 R. R. BOLT 3,191,422

IjvIEJx'OD AND APPARATUS FOR FORMING METAL ARTICLES Filed Jan. l0, 1961 3 Sheets-Sheet 1 W1. ,I -f/A w i f'/ @www June 29, 1965 Filed Jan. l0. 1961 3 Sheets-Sheet 2 IN V EN TOR.

Arm/Mins June 29",- 1965 R. R. BOLT 3,191,422

METHODl ANDl AFPHRALTUS FOR FORMING METAL ARTICLES Filed Jan., 103J 1961 s sheets-sheet s /f' /M @"5 j IN VEN TOR.

United States Patent() 3,191,422 METHOD AND APPARATUS FOR FORMING j METAL ARTICLES Richard Robert Bolt, Lake Villa, Ill., assignor to American vCan Company, New York, N.Y., a corporation of New Jersey Filed Jan. 10, 1961, Ser. No. 81,727 9 Claims. (Cl. 72-344) The present invention relates to the production of thin walled cylindrical cup-shaped metal articles -having a short` tubular neck extending outwardly from the endsurf-ace, and has particular reference to a method of andapparatus Ifor completely forming Isuch an article from a ilat metal blank in one continuous forming operationf i Cup-shaped articles fabricated from thin sheet metal such as tin plate and having a short tubular-shaped opening in the end portion are widely employed as container components. Such a cup-shaped article may -be used as the end closure of a conventional container body or, where the formed cup has a relatively long side wall, may serve as a one -piece combined can body and end. In either case, the short tubular neck is used as the means for retaining a closure cap, 'dispensing spout, dispensing valve, or the like on the container end.

Heretofore, the fabrication of metal articles of the subject type has been accomplished by a series of separate `successive operative steps. fa flat lblank of sheet metal such as tin plate is first drawn into the desired cup form. In subsequent separate operiations, a closed tubular neck of desired length is formed on the end surface of the drawn cup and the closed end of the tubular neck is then opened by a piercing operation.

While the methods and means presently used achieve the desired result, the forming and piercing 4operations to produce .an open tubular neck on a drawn cup necessitate the use of special machinery and tooling therefor. Furthermore, these operation-s necessarily result in handling and processing costs which add to the overall cost of the completed article. However, by the novel method Vand means disclosed herein, metal articles of the subject type can be completely formed in a single continuous forming operation thereby eliminating the need for the special machinery and tools to perform the separate forming and piercing operations with a consequent savings in equipment and processing costs.

Y Accordingly, an object of the present invention `is .to provide an improved method of forming a thin-walled cupshaped metal article having a short open tubular neck extending outwardly from the end surface without the need for separate forming an-d piercing operations on the end surface of a previously drawn cup.

Another object is to provide such a method wherein the open tubular neck is formed duringand as part of the cup forming operation.

Another object is to provide such a method which requires less production equipment and tooling as compared to methods heretofore used.

A further 4object lis to provide a method of forming `such a cup-shaped Iarticle having a circular cross section with a depth which exceeds the diameter and a sidewall thickness substantially less than the thickness of the original blank.

Yet a further object isto provide an apparatus for forming such a cup-shaped article wherein the forming of the cup portion and the forming of the open tubular neck portion is .accomplished in a simultaneous operation.A

lStill a further object is to provide such an apparatus in which the side wall is reduced to `a thickness substantially less than the thickness of the original blank inthe same continuous operation. i

In the methods generally used,

'ice

Numerous other objects and advantages ofthe invention will be apparent as it is better understood from the followmg description, which, taken in connection with the accompanying drawings, discloses a preferred embodiment thereof.

The above objects are accomplished in the present invention by providing a ilat circular blank A of thin sheet metal such as tin plate having a centrally disposed circular hole B. A blank -holder C positions the blank A over an annular drawing die D yand presses the edge or marginal portion of the blank .against the die with a substantial force. A punch E having a cylindrical forming plug F integral with its end surface forces the blank A through the die D thereby drawing the flat blank into a cup form while pulling the marginal portion out from beneath the blank holder C. The force exerted by the blank holder C on the marginal portion of the blank B prevents wrinkling or folding of the blank as it is being forced through the die D and must be suicient to insure that the blank is smoothly stretched as it is being drawn. The plug F having -a diameter larger than that of the hole B is forced through the hole B during the drawing operation causing the metal adjacent the hole to be distended and stretched around the plug toform a tubular neck on the end surface of the drawn cup.

The cup thus formed has a side wall thickness substantially equal to the thickness of the blank. It desired, the diameter of the cup may be reduced and the side wall decreased in thickness in one continuous operation by forcing the initially drawn cup through one or more ironing dies positioned below and in close succession to the drawing die D.

Numerous other objects and advantages of the invention will be apparent as it is better understood from the following description, which, taken in connection with the Iaccompanying drawings, discloses a preferred embodiment thereof.

Referring to the drawings:

FIGURE 1 is a sectional view of a metal forming apparatus embodying features of the present invention;

FIG. 2 is a fragmentary view similar to FIG. l showing the parts after the blank is drawn Vto the cupped form;

FIG. 3 is an elevational View of a modified form of the invention; t

FIG. 4 is a vertical sectional view of the embodiment shown in FIG. 3;

FIGURES 5 and 6 are partial sectional views similar to FIG. 4 showing the parts in other positions of the operating cycle;

FIG.V 7 is a vertical sectional View of the control valve of FIG. 3.

As a preferred or exemplary embodiment of the instant invention FIG. l shows a hydraulic metal drawing press generally designated 11 having a bolster plate 12 attached to a frame 13. An annular drawing die D having a die aperture 14 is suitably mounted upon the bolster plate 12 .t the bolster plate 12 with the shank portions extending upwardly through the holes 16 in the blank holder C to prevent the blank holder from moving transversely relative to the die D while permitting it to move upwardly along the longitudinal axis of the die.

The lower surface of the blank holder C has a circular recessed portion 2@ of substantially the same diameter as Y through the die D. Generally,

alan-sae that of the blank A and a depth which is slightly less than the thickness of the blank, the recessed portion serving to position the blank in axial alignment with the die aperture 14. As thus positioned, a marginal edge portion 23 of the blank A is gripped between the die D and the blank holder C with a substantial predetermined force due to the action of compressed springs 24 disposed on the stud Shanks 1S between the blank holder and stud heads 19.

A cylindrical drawing punch E reciprocably mounted above the blank holder C in axial alignment with the die aperture 24 has a lower end surface 25 with an axially disposed cylindrical forming plug F integral therewith. The upper end of the punchr E is attached to the piston rod Z6 of a hydraulic actuating cylinder 27, the cylinder being secured to the frame 13 of the machine and having upper and lower ports 2S and 29 respectively.

The admission of pressurized hydraulic fluid from a suitable source (not shown) to the cylinder 27 through the upper port 28 moves the punch E downwardly. The forming plug F initially contacts and is forced through the blank A, the metal adjacent the central aperture B in the blank being forced downwardly and draped or stretched about the plug to form a tubular neck 3l?. The subsequent continuous movement of the punch E forces the blank A through the die aperture 14, shaping and stretching the blank over the punch to form a cup-shaped article 35 (FIG. 2). During this operation, the force with which the marginal edge portion 2.3 of the blank A is gripped between the blank holder C and drawing7 die D is sutlicient to insure that the blank is plastically stretched rather than being wrinkled or folded as the marginal portion is withdrawn yfrom beneath the blank holder and drawn through the die, but is not so great as to result in tearing or cracking of the metal as a result of excessive stretching during the forming of the cup 33.

The formed cup 33 has an end 34 and side wall 35 both having a wall thickness approximately equal to the thickness of the blank A. The shape of the end surface 25 of the punch E determines the shape of the end 34 of the drawn cup 33 and may be conical, a combination of conical and spherical shapes, etc. referably, the end surface 25 is the conical surface of a truncated cone. Y However, the conical angle of the end surface 25 must not be too small, since a too sharply pointed punch E tends to distend and fracture the blank A rather than to draw it a minimum conical angle of 120 is desirable, although small angles may be successfully used. A

The continuous downward movement of the punch E carries the formed cup through a conventional stripper disposed below the die D. The stripper consists of a segmented tlat annular ring 36 having a series of segments 37 adapted to slide radially within a recessed portion 38 in the lower surface of the bolster plate 12. The segments 37 are urged radially inwardly by springs 39 and are retained within the recessed portion 33 by an annular llat retaining ring itl secured to the bolster plate 12 by screws 43. At

the extreme inwardly position of the segments 37, the segmented ring 36 has a substantially cylindrical inner surface 44 whose diameter is slightly less than thediameter of the punch E with a smoothly rounded upper edge 45 and a sharp lower edge do.

As the formed cup 33 is conveyed towards the stripper by the punch E, it contacts the rounded upper edge 45 of the segmented ring 36 forcing the segments 37 outwardly to allow the cup to pass through the ring. After the cup 33 has passed through the ring 36,' the springs 39 move the segments 37 inwardly against the punch E. By suitable valving means (not shown), the flow of pressurized hydraulic lluid is then directed to the lower port 29, whereupon the punch E is moved inwardly by the actuating cylinder 27. During theupward movement of the punch E, the upper edge of the formed cup 33 engages the sharp lower edge 46 of the segmented ring Se which prevents any further upward movement of the cup, therel by stripping it from the punch. To facilitate its withdrawal fromthe tubular neck Sil, the forming plug F 1s preferably provided with a very slight inward taper in the direction away from the end surface 25 of the punch E. However, the taper is not apparent in the drawings because of its small magnitude and the reduced scale of the drawings.

In the modied form of the invention shown in FlG- URES 3 and 4, the blank A is forced successively through drawing and ironing dies in a single continuous operation to form an elongated cup-shaped article having a tubular neck extending outwardly from 4the end surface. As used herein, the term drawing refers to the operation wherein a fiat blank is formed into Ya cup having a Iside wall thickness approximately equal to the thickness of the loriginal blank; inoning refers tothe operation wherein the -side wall of the drawn cup is substantially reduced in thickness and increased in length, with or without a substantial reduction in the outside diameter of the drawn cup, by ironing the `side wall between a punch and die as the punch forces the Icup through the die.

Referring to FIG. 4, a llat circular metal blank A having a centrally located hole B is positioned and held between a drawing die D and blank holder C in the same manner as hereinbefore'described for the preferred embodiment of .the invention. Mounted abo-ve lthe blank holder C is a forming punch comprising a cylindrical inner punch 47 having a flat upper end surface i8 and a conical lower end surface 49 .slidably `disposed within a tubular router punch 5th of circular cross section and having a conical lower end surface l53. lntegral with the lower end surface 49 of the inner punch 47 is an axially positioned cylindrical forming plug In the extreme upward position of the inner punch 47 relative to the outer punch 50, the upper end surface 48 of the inner punch abuts a flange :54 integral with the inner surface of the outer punch. In this position, the lower end surfaces 49 and 53 of the inner and outer punches 42-71and 50 respectively together form a .continuous surface which is the conical surface of a truncated cone (FIGUR-ES 4 and 5). For the reasons hereinbefore stated, the end surfaces 49 and 53 preferably have a minimum conical vangle of 120.

The outer punch 59 is vertically reciprocable by means of two conventional hydraulic actuating cylinders 55 disposed on opposite sides of the punch and secured to frame members 56. The cylinders -55 have downwardly extending piston rods 57 which are `secured t0 la horizontal member 58 integral Vwith the outer punch 5h intermediate its ends.

Actuation `of the hydraulic cylinders 5S is preferably effected lthrough -a manually loperated, three-position coutrol valve 59 of a type well known in the art. The valve 59 has a cylindrical valve slide e@ slidably dispo-sed 'within a closed housing 63 (FIG. 7). The slide et) is provided with a stem 64 which extends through one end of .the housing 63 .and is connected to a pivotally mounted hand-le 65. The handle 65 is manu-ally manipula-table to each of three positions by an operator and, as shown in FIGURES 3 and 7, is in the neutral middle position.

A pump 66 operated continuously by any suitable means such as yan electric motor 67 pressurizes hydraulic fluid from a reservoir 68 and delivers. it through a connecting pipe 69 to an inlet port 7@ .of the control valve. With 'the valve slide dll in the neutral position, a circumferential groove 73 connects the inlet port 7@ with a return port 74. The return port 74 is connected to the reservoir 63 by a pipe 75, thereby providing continuous circulation of pressurized hydraulic fluid from the pump 66 through the valve 59 back tothe reservoir 68 when the slide dll is in the neutral position. Also, while the sl-ide 16) is in the neutral posi-tion, a pair of U-shaped channels 76 and 77 formed in .the slide on each side of the circumferential groove .73 straddle valve openings 7S yand 79 re-V spectively, thereby ellectivelyfsealing these valve openings.

Movement of the valve handle 65 to the right as viewed in FIG. 7 shifts the slide 60 toward the right out of the neutral position and into a position wherein the circumferential groove 73 is out of register with the return port 74, thereby cutting off the direct ow of pressurized hydraulic lliuid from the pump 66 back to the reservoir 68. At the same time and in this position of the slide 60, one leg of the U-'shaped .channel 77, the right lega-s viewed in FIG. 7, is in communication with `an end space -80 adjacent the right end of the housing 63 and the opposite leg of the channel 77 is in communication with the valve opening 79. Similarly, the U-shaped` channel 76 connects the valve opening 78 to the return pont 74.

Thus the pressurized fluid iiows from thevalve inlet port 70 to and `through a longitudinal groove 83 in the slide 60 connecting the inlet port with the end `space 80, through the U-'shaped channel 77 to the Valve opening 7 9, through a branched tube 84 and hoses 85 connecting the valve opening 79 and upper port opening-s 86 in the actuating cylinders 55 into the upper ends of the cylinders. This results in a downward movement of the horizontal member 58 and the integrally connected outer punch 50 with the iiuid in the lower portions of the actuating cylinders escaping through lower ports 87 to and through hoses 88 and la branched tube 89 connecting the lower ports 87 to the valve opening 78, through the U-shaped channel 76 to the return port 74, and through the pipe 75 back to the reservoir 68. Simultaneously and in unison with the downward movement of the outer punch 50, the inner punch 47 moves downwardly, with the upper end surface 48 of Ithe inner punch abutting the ilange 54, thereby maintaining the adjacent portions of the lower end surfaces 49 and 53 ofthe inner and outer punches respectively in the desired flush relationship.

The forming plug F initially contacts and is forced through the apertured bl-ank A to form a tubular neck 96 and the subsequent unified movement of the punches 47 and 50 through the drawing die D draws the blank 'into a cup-shaped article `)3 in the manner previously set forth in detail for .the preferred embodiment of the invention. The drawn cup has a sidewall 94 and a bottom 95, the bottom having a conical shape corre-sponding to the flush conical end surfaces 49 and 5-3 of the inner and outer punches 47 and 50 respectively.

After completely emerging from the drawing die D,

the drawn cup 93 is carried downwardly until a peripheral portion of the conical cup bottom 95 engages a similarly shaped conical depression 98 in the upper surface of the first of two annular ironing dies 99 and 100 (FIG. 5). The ironing dies 99 and 100 are mounted in the bolster plate 12 below and in axial alignment with the drawing die D. An annular spacer plate 101 is disposed between the drawing die D and first ironing die 99, and a spacer plate 102 separates the first and second ironing dies 99 and 100 respectively. As the cup bottom 95 engages the conical depression 98 in the rst ironing die 99, the horizontal member 58 concurrently engages and closes a switch 103 secured to the frame member 56 above the blank holder C. Closing of the switch 103 energizes and opens an electrically operated solenoid valve 104 allowing pressurized fluid to flow from the branched tube 84 through a connecting hose 105 to an upper port opening 106 of an inner punch actuator 107.

The actuator 107 has a cylinder wall 108 formed by the upper portion of the outer punch 50 with an upper end 109 threadably secured thereto and with the lower end formed by the ange 54. A piston 110 slidably disposed within the cylinder wall 108 has a piston rod 111 extending downwardly through the end flange 54 and attached to the upper end surface 48' of the inner punch 47.

The pressurized uid owing into the actuator 107 through the upper port 106 forces the piston 110 downwardly, which moves the inner punch 47 downwardly independently of the outer punch 50. During this moveeLO ment, the fluid in the lower portion of the actuator 107 below the piston escapes through a lower port opening 112 through a connecting hose 113 to the branched tube 89 and thence through the valve opening 78, channel 76, return port 74, and pipe 75 back to the reservoir 68.

The downward movement of the inner punch 47 forces the drawn cup 93 successively through apertures 114 and 115 in the iirst and second ironing dies 99 and 100 respectively, reducing the side wall thickness and producing an elongated drawn and ironed cup-shaped article 116. The drawn and ironed cup 116 has an end 117 of thickness substantially the same as that of the blank A and a side wall 118 whose thickness is substantially less than that of the blank.

During the ironing operation, the actuating cylinders 55 continue to press the outer punch 50 downwardly toward the conical depression 98'in the ironing die. Consequently, a substantial pre-determined holding force is exerted on the cup material as it ows between the conical end surface 53 of the outer punch 50 and the conical depression 98 in the ironing die 99. This holding force prevents wrinkling or folding of the Vside wall 94 as the drawn cup 93 is being ironed. It also increases the permissible amount of cold working of the metal in the first ironing die 99 without causing it to tear. While not wishing to be bound by any particular theory, it is believed that the holding force results in a back stressing of the metal entering the first ironing die which permits a greater deformation of the metal without the excessively high die pressure which would otherwise result and which would cause overstressing and rupture of the material as it is pulled from the die.

The continued downward movement of the inner punch 47 carries the drawn and ironed cup 116 through a segmented stripper' ring 36 identical to that hereinbefore described for the preferred embodiment of the invention. After the punch 47 has reached its lowermost position, movement of the control valve handle 65 to the left as viewed in FIG. 7 shifts the slide 60 toward the left and also engages and closes a switch 119 mounted adjacent the handle. The switch 119 is connected in parallel to the switch 103 so that the closing of either switch energizes and opens the solenoid valve 104.

In the new position of the slide 60, the U-shaped channel 76 connects the valve opening 78 to an end space 120 adjacent the left end of the housing 63. Thus, the pressurized fluid from the pump 66 ows from the valve inlet port through the longitudinal groove 83 in the slide 60 connecting the inlet port with the end space 120, through the U-shaped channel 76 to the valve opening 78, through the branched tube 89 and hoses 88 and 113 connecting the valve opening 78 to the lower port openings 87 and 112 respectively, and through the lower ports 87 and 112 into the actuating cylinders 55 and 107 respectively, causing the outer and inner punches 50 and 47 to move upwardly,

Concurrently, the U-shaped channel 77 connects the valve opening79 to the return port 74, permitting the fluid in the upper portions of the actuating cylinders 55 and 107 to iiow through the upper ports 86 and 106 and connecting hoses 8S and 105 respectively and thence through the tube 84, channel 77, and pipe '-75 back to the reservoir 68.

On moving upwardly, the horizontal member 58 disengages the switch 103, causing it to open. However, the solenoid valve 104 is maintained in the energized open position during the upward movement of the punches 47 and 50 by the closed switch 119. As the inner punch 47 moves upwardly, the lower edge 46 of the segmented ring 36 engages the upper edge 121 of the side wall 118 of the formed article 116, stripping the formed article from the punch.

It is apparent that by the use of the apparatus described, which also exemplifies the method steps required for consummating the process of the invention, it is possible to form in a single continuous stroke a cup shaped metal article having a short tubular neck extending longitudinally outwardly from the end surface. The article thus formed may have a relatively short side wall height by employing a single drawing operation, or the side wall may be made relatively long as compared to the diameter of the formed article by using one or more ironing dies positioned below and in close succession to the drawing die so that in a single continuous stroke, the blank is first drawn into a cup form and the drawn cup then carried through the ironing dies to reduce its diameter and the thickness of the side wall.

As compared to methods and apparatus 'heretofore in use for forming such articles, theV subject invention requires substantially less equpiment and installation space therefor since the formation yof the tubular neck takes place simultaneously with the cup forming operation. The elimination of the additional equipment required to form and pierce the tubular neck and the operating steps involved results in savings in fabrication costs which may Vreach substantial proportions, e.g.,V at the high rates of production generally required when the formed articles are to be used for container components.

It is thought that the invention and many of its attendant advantages will be understood from the foregoing description and it will be apparent that various changes may be made in the form, construction, and arrangement of parts of the apparatus mentioned herein and in the steps and their order of accomplishment of the method described herein, without departing from the spirit and scope of the invention or sacrificing all of its material advantages, the apparatus and process hereinbefore described being merely a preferred embodiment thereof.V

I claim:

' l. An apparatus for forming a thin metal blank having 'a hole therein into a cup-shaped article having a side wall and an end with a longitudinally extendingVopen-ended tubular neck disposed on said end comprising, a die having a die aperture, metal working surface means on said die aperture for cold working said 1blank material as said material is slidably moved across and in contact with said surface means, a holding ymember adapted toposition and releasably hold a peripheral margin of said blank against said die with a predetermined forceya punch reciprocably mounted in axial alignment with said die aperture, an end surface on said punch, means for moving said punch through said die aperture and withdrawing all of saidperipheral margin from between said holding member and said die and transporting all of said peripheral margin across and in contact with said surface means to form all of said peripheral margin into a side wall portion of `a cup-shaped article having an end, and plug means disposed on said punch end surface for forming an openended tubular neck extending longitudinally outwardly from said end by distending a portion of said end adjacent saidY hole simultaneously with theV forming of said side Wall portion of said cup-shaped article.

2. The vapparatus set forth in claim l wherein said die aperture and the cross section of said punch are circular, said punch and die being adapted to'form a disk-shaped blank having a centrally located circular hole therein into a cylindrical cup-shaped article having a centrally disposed tubular neck of Icircular cross section extending longitudinally outwardly from said end.

3. The apparatus set forth inyclaim l wherein said forming plug has la slight inward taper in the direction away from said end surface to facilitate withdrawal of said plug from the tubular neck formed on the end of said cup shaped article.

corresponding to the desired shape of the end of said cupshaped article.

5. The apparatus set forth in claim 4 wherein said endy ci surface is substantially in the form of a frustrum of a cone.

6. An apparatus for forming a cylindrical cup-shaped article having side walls and an end with a longitudinally extending tubular neck centrally disposed on said end froma thin, disk-shaped metal blank having a centrally located circular hole therein comprising, a drawing die, a holding member disposed above said drawing vdie adapted to position and yieldingly hold a peripheral margin of said blank against said die with a predetermined force, a punch comprising concentric inner and outer members, said inner member being cylindrical in shape with van end surface, said outer member having a circular cross section with a conical end surface and being slidably disposed on said inner member, a cylindrical forming plug integral with said end surface of said inner member, said plug having `a diameter which is greater than the diameter of the hole in said disk, means for moving said punch members in unison through said drawingdie to withdraw said peripheral margin from between said holding member and said die and'move said blank including said peripheral margin through said die to draw said blank into a cupshaped article having side walls and an end and simultaneously therewith forcing said plug through said hole to distend the metal adjacent said hole Vand form an open tubular neck extending longitudinally outwardly from the end thereof, at least one ironing die disposed below and in close succession to said drawing die, the uppermost ironing die having a conical depression in the upper surface thereof corresponding in shape to the conical end surface of said outer member, and means associated with said first mentioned means for moving said inner member through said ironing dies to force said drawn article therethrough while said outer member holds said drawn article against said conical depression with a pre-determined force whereby the side wall of said drawn article is reduced in diameter and decreased in thickness land its length correspondingly increased.

7. A method of making a cylindrical cup-shaped metal article having side walls and an end with 1a tubular neck extending longitudinally outwardly from said end comprising the steps of, providing a thin disk-shaped metal blank having a circular hole therein, positioning and yieldingly holding a peripheral margin of said blank against a ring die element with a predetermined force, forcing said blank including said peripheral margin through said die element to form a cylindrical cup-shaped article having side walls and an end, and simultaneously with said cup forming operation forming the metal adjacent said hole into yan open tubular neck.

S. The method set forth in claim 7 with the additional step of forcing said cup-shaped article through at least one additional ring die element disposed below and in close succession to said rst mentioned die element, thereby reducing the thickness of and elongating said side wall in a single continuous operation.

9. An apparatus for forming la metal blank having an aperture therethrough into a hollow cup-shaped article having a side Wall and an end with a longitudinally extending open-ended tubular neck disposed on said end comprising, a punch having a longitudinal axis and an end surface, said punch having a portion of substantially uniform cross-section as measured in the direction transverse to said axis and a side surface comprising the surface of said portion, holding means adapted to position and releasably press a peripheral margin of said blank against a holding surface with a predetermined force, a die having a die opening in axial alignment with said longitudinal axis of said punch, said die opening comprising a metal working surface with the area of said opening as measured in the direction transverse to said longitudinal axis corresponding in shape but being greater than said punch portion crosssection area, said holding surface comprising a surface of said die surrounding said die opening, means for moving said punch through said die opening and progressively withdrawing all of said peripheral margin from between said holding means and said holding surface and carrying said margin past and in contact with said working surface of said die opening to form all of said peripheral margin into close conformity and engagement with said side surface of said punch whereby said peripheral margin is entirely formed into 'a side wall portion of a cup-shaped article having an end, said holding means being adapted to maintain said force on the portion of said peripheral margin in contact with said holding surface las said peripheral margin is progressively withdrawn from said holding means and forced through said die opening, and plug means disposed on said punch end surface for forming an open-ended tubular neck extending longitudinally outwardly from said end by distending a 15 portion of said end adjacent said hole simultaneously with the forming of said peripheral margin into conformity and engagement with said side surface of said punch.

References Cited by the Examiner UNITED STATES PATENTS 2,190,659 2/40 Guerin 113-44 2,234,225 3/41 Becker 113-44 2,412,813 12/46 Keller 113-49 2,531,663 11/50 Bignella et al. 113-42 2,602,411 7/52 Schnell 113-46 2,664,061 12/53 Rhodes 113-46 2,821,156 1/58 Lyon 113-49 2,878,513 3/ 59 Slaughter 18-19 2,929,345 3/ 60 Zatyko 113-51 2,943,587 7/ 60 Samuelsson 113-51 WILLIAM I. STEPHENSON, Primary Examiner.

NEDWIN BERGER, Examiner.

Claims (1)

1. AN APPARATUS FOR FORMING A THIN METAL BLANK HAVING A HOLE THEREIN INTO A CUP-SHAPED ARTICLE HAVING A SIDE WALL AND AN END WITH A LONGITUDINALLY EXTENDING OPEN-ENDED TUBULAR NECK DISPOSED ON SAID END COMPRISING, A DIE HAVING A DIE APERTURE, METAL WORKING SURFACE MEANS ON SAID DIE APERTURE FOR COLD WORKING SAID BLANK MATERIAL AS SAID MATERIAL IS SLIDABLY MOVED ACROSS AND IN CONTACT WITH SAID SURFACE MEANS, A HOLDING MEMBER ADAPTED TO POSITION AND RELEASABLY HOLD A PERIPHERAL MARGIN OF SAID BLANK AGAINST SAID DIE WITH A PREDETERMINED FORCE, A PUNCH RECIPROCABLY MOUNTED IN AXIAL ALIGNMENT WITH SAID DIE APERTURE, AN END SURFACE ON SAID PUNCH, MEANS FOR MOVING SAID PUNCH THROUGH SAID DIE APERTURE AND WITHDRAWING ALL OF

Images