US2131027A - Method and apparatus for working sheet metal articles - Google Patents

Description

Sept. 27, 1938. J. W. FRE NCH ET AL 7 METHOD AND APPARATUS FOR WORKING SHEET METAL ARTICLES Filed Jan. 22, 1937 4 Sheets-Sheet 1 Sept, 27, $338; .J. w. FRENCH ET AL '4 Sheets-Sheet 2 Filed Jan. 22, 193'7 P 1938- J. w. FRENCH ET AL 2,131,027

METHOD AND APPARATUS FOR WORKING S HEET METAL ARTICLES Filed Jan. 22, 1937 4 Sheets-Sheet s I /f r Iil Ill

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Sept. 27, 1938 J w, FRENCH ET AL 2,131,027

METHOD AND APPARATUS FOR WORKING SHEET METAL ARTICLES Filed Jan. 22, 1937 4 Sheets-Sheet 4 Fly. 6

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Patented Sept. 27, 1938 PATENT OFFICE METHOD AND APPARATUS FOR WORKING SHEET METAL ARTICLES John W. French, Warren, and John 0. E. Carlson Youngstown, Ohio, assignors, by mesne assignments, to Mullins Manufacturing Corporation, Salem, Ohio, a corporation of New York Application January 22, 1937, Serial No. 121,860

24 Claims.

The invention relates to the working of sheet metal articles such as sheet metal receptacles; and more particularly the invention has special application to methods and apparatus for forming a bullet-nose or bottle-neck shape at the upper or open end of the side walls of a relatively deep receptacle or container having integral bottom and side walls all formed or drawn'from a single piece or blank of sheet or plate metal.

Such receptacles may be used for many purposes, for example, as tubs for power-driven washing machines; and bullet-nosed or bottle-necked tubs for washing machines, or for wringerless driers have recently come into considerable demand. Moreover, such receptacles are usually made of a ductile material such as rolled strip or sheet steel and are usually covered with a vitreous enamel coating.

Difficult drawing operations are involved in the manufacture of such receptacles, per se, because the same are relatively deep and are drawn or formed from a single piece or blank of metal; and in the past, the upper or open ends of such receptacles have been finished preferably by providing a relatively shallow and wide inwardly extending circumferential rib spaced below the top of the receptacle and by providing a turned or rolled false wire bead immediately above such rib, as is shown for instance in the Stanitz and twenty-three inches in diameter deep drawn from a single sheet metal blank, because such bullet-nose orbottle-neck formation may decrease the diameter of the open upper end of the receptacle as much as three or more inches. Thus, a substantial amount of material must be displaced and rearranged in the upper end of the circumferential walls of the receptacle, which metal walls athough composed of ductile material, have alreadybeen subjected to most severe deep drawing operations in forming the receptacle of such depth from a single metal blank.

Different methods have been proposed and used for forming a bullet-nose or bottle-neck shape in such receptacles, but the same have not been satisfactory because of excessive costs due to numerous operations required and to large amounts of material scrapped.

Thus, the manufacture of such receptacles has been accomplished by a hot spinning method. Initially, a receptacle is drawn some four to six inches deeper than its ultimate size and is then placed in a spinning machine in which the bottom is clamped for rotating the recepetacle and a circumferential band of the receptacle at and adjacent to the open upper end thereof is heated by a flame heater while the receptacle is being rotated. After the wall portion has become red hot, it is worked by a hand controlled spinning roll against a properly shaped mandrel to rough form the bottle-neck contour. The receptacle is then placed on a second spinning machine where sizing rolls operate upon the rough formed end to give the receptacle the proper size and contour. The excess material necessary in order to carry out the hot spinning operation is then cut oif at the upper end of the receptacle above the region where the bullet-nose or bottleneck shape has been formed.

While receptacles 'may be produced in this manner, the mere recitation of the steps required in the hot spinning process for providing the bottle-neck formation discloses the slowness, expense and waste encountered in carrying out the same.

Another method has been proposed for making receptacles with bullet-nose or bottle-neck shapes in the upper ends thereof. In this method, the receptacle is drawn and is then subjected repeatedly to cold spinning, annealing and pickling operations which result in successive small reductions in the diameter of the open end of the receptacle, and are repeated until the total substantial reduction necessary to form the bulletnose or bottle-neck shape has been obtained. The very recitation of such a method, however, discloses the slowness and expense encountered, not only in carrying out numerous spinning, annealing and pickling operations, but in handling the receptacles back and forth between the spinning machines, annealing furnaces, pickling vats, etc.

It is therefore a principal object of the present invention to provide a new improved and inexpensive method of forming a bullet-nose or bottle-neck shape at and adjacent to the end of a cylindrical article formed of a single sheet or blank of sheet or plate metal.

It is a further object of the present invention to provide improvedapparatus for formig a bottle-neck or bullet-nose shape circumferentially in the wall of a cylindrical object at and adjacent to an end thereof.

A further object of the present invention is to provide an inexpensive method and improved apparatus for forming a bullet-nose or bottle-neck shape at the upper end of a closed bottom sheet metal receptacle deep drawn from a single blank of metal.

Likewise, it is an object of the present invention to provide a method and apparatus for forming a bullet-nose or bottle-neck shape in the upper open end of a closed bottom sheet metal receptacle by a new, improved and simplified cold working operation which may be quickly, readily and easily performed without waste of material, and without repeated working, annealingand pickling operations.

A further object of the present invention is to provide a new method of cold working metal, which is neither a spinning operation, nor a drawing operation, nor a bending operation, but which involves some of the elements of each of such operations.

A further object of the present invention is to provide a method and apparatus for metal working in which a cylindrical closed bottom receptacle of fixed height and substantially uniform diameter has its upper open end reduced in diameter to a considerableextent to form a bulletnose or bottle-neck shape without altering the height of the receptacle; by working the metal between roller dies, which pinch, hold and work the metal under pressure and yield and are displaced by one another as the re-shaping pro gresses.

Moreover, it is an object of the present invention to provide a method and apparatus for metal working in which the rotating extremities of cylindrical material being worked are maintained in fixed planes spaced a constant axial distance at all times, in which pressure is applied between roller dies to thematerial intermediate said fixed planes to reduce the diameter of the material, and in which the material is maintained under tension or stretched at and adjacent to the region where pressure. is being applied to the material by the roller dies in working the material. f

Moreover, an object of the invention is to provide apparatus for working cylindrical material,

I including roller dies for working the material as the material is. being rotated, and meansfcr holding successive elements of. the material, which pass through the successive places being worked, in a plane which also passes through the cylindrical axis of the material, so as th hold the material in alignment and prevent the cylindricalmaterial from wabbling or chattering while being worked. i

Similarly, it is an object of the present invention to provide improved apparatus for metal working in which a cylindrical closed bottom receptacle is worked between roller dies at and adjacent to its upper or open end, with means for holding the upper or openend of the material substantially in true cylindrical shape while being worked, so as to prevent the same from becoming oval-shaped or out of round.

Moreover, an object of the present invention is to provide improved apparatus for metal workinn in which cylindrical material is worked between a plurality of roller dies, with yielding mounting means for one or more of said dies.

Moreover, it is an object of the present invention to provide a method and apparatus for metal working in which cylindrical material is provided with an outturned annular flange at least at one of its extremities, in which the material is worked between roller dies adjacent to said outturned flange, and in which said outturned flange is held substantially in a fixed plane as the metal at and adjacent thereto is being stretched, reduced and worked.

Further objects of the improvements set forth herein include the provision of an improved general and detail arrangement of certain parts of the improved apparatus so as to attain an improved mode of operation for carrying out the improved method hereof to produce the improved products disclosed herein.

And finally, it is an object of the present invention to provide an improved method and improved apparatus for making bullet-nose or bottle-neck shapes in' closed bottom receptacles of difierent sized diameters and heights deep drawn integrally from single metal blanks which satisfy the desiderata described above, which may be car ried out in an inexpensive manner with a minimum of operations, cost and waste, and with which the improved bullet-nosed or bottle-necked sheet metal receptacles disclosed herein maybe made.

The foregoing and other objects are attained by the steps, methods, procedures, processes, apparatus, parts, combinations, sub-combinations and products which comprise the present inven-' tion, the nature of which is set forth in the following general statements, preferred embodiments of which are set forth in the following description, and which are particularly and distinctly pointed out and set forth in the appended claims forming part hereof. a

The nature of the improved method of the present invention may be stated in general terms as including among others, the steps of forming a closed bottom receptacle from a single blank of metal by a deep drawing operation, forming an annular flange at the open upper end thereof, thereafter working the metal at and adjacent to said flange to provide a bottle-neck or bullet-nose formation thereat, preferably carrying out' the working operation promptly after the deep drawing operation while the metal is working operation being accomplished preferably by rotating the receptacle about an axis by maintaining successive elements thereof in contact with a rotating roller die mandrel, maintaining the receptacle in alignment on said mandrel, maintaining the open end of the receptacle substantially in cylindrical shape while rotating, maintaining the flange and bottom of said receptacle substantially in fixed planes a constant distance apart perpendicular to the axes of the receptacle and mandrel while rotating, applying moving roller die pressure to the receptacle at and adjacent to the rotating flange thereof, moving the pressure applying roller toward the axes of the receptacle and mandrel roller die to pinch, hold, work and stretch the metal under pressure between the roller dies, permitting one or more of the roller die parts to yield as the working operation progresses and preferably slowing down the working operation as the diameter of the open end of the receptacle decreases in forming the bottle-neck or bullet-none lhm.

still warm from the drawing operation, said 50 shape at the upper end thereof;

Fig. 6 is a view similar to Fig. 4, showing a deep means for positively rotating at least one of said roller dies to by contact rotate the material to be worked, means for holding the material being worked in alignment between the roller dies, said last mentioned means preferably including yieldl5 ing means the pressure of which increases as the work progresses, means for holding cylindrical material being worked substantially in cylindrical shape, means for adjusting certain of said means to accommodate various sized articles to be worked,

20 and certain of said means including means for maintaining the extremities of the material being worked in fixed planes a constant distance apart as portions of the material intermediate the extremities are being worked between the roller 25 dies.

The nature of the improved product will more fully and at large appear in the following description.

By way of example, preferred embodiments of 30 the improved apparatus for'carrying out the improved method are illustrated in the accompanying drawings forming part hereof, in which Figure 1 is a fragmentary side elevation of a standard type of beading machine equipped with 35 the improved apparatus for working sheet metal articles, certain parts of the improved apparatus being broken away and in section;

Fig. 2 is a front elevation, certain parts being shown in section, of the apparatus shown in Fig. 3 is a fragmentary view similar to portions of Fig. 1, showing a modified-form of roller dies; Fig. 4 is a side elevation with a part broken away and in section, showing a deep drawn receptacle blank prior to being worked by the apparatus of Fig. 1;

Fig. 5 is a. view similar to Fig. 4, showing the receptacle after being worked by the apparatus of Fig. 1 to provide a bullet-nose or bottle-neck drawn receptacle blank to be worked by the apparatus of Fig. 3; V

Fig. 7 is a view similar to Fig. 5, showing a com- 55 pleted receptacle having a bullet-nose or bottleneck shape at the upper end thereof after havh g been worked by the apparatus of Fig. 3; 5

Figs. 8, 9 and 10 show successive stages of the working operation carried out by the apparatus Cc of Fig. 1 to form the receptacle shown in Fig. 5

from the receptacle blank shown in Fig. 4;

Figs. 11, 12 and 13 show successive stages of the working operation carried out by the apparatus of Fig. 3 to form the receptacle shown in Fig. 7

65 from the receptacle blank shown in Fig. 6; and

Fig. 14'is an enlarged view of certain of the parts shown in Figs. 1 and 9, illustrating a detail in .construction.

Similar numerals refer to similar parts through- 7 out the various figures of the drawings.

75 each of which include two driven spindles. In one type of beading machine there is an upper head having one driven spindle mounted for sliding movement toward and away from a lower head having another driven spindle; and in another type of beading machine there is an upper head having a driven spindle pivotally mounted for movement toward and away from a lower bead having another driven spindle.

The latter type of beading machine is more or less diagrammatically illustrated in the drawings; and in all types of beading machines the upper movable head may. be moved toward and away from the base by any suitable control means, either by hand, or by power cylinders, or by a mechanical drive, any one of which control means may be regulated to control therate of movement of the upper head toward or away from the lower head or housing.

The upper head of the beading machine is shown in IS and the lower head or base housing at IT. The member carries a side arm l8 in which the upper head I6 is pivotally mounted at |9 through the medium of'the arm 20. The upper headis movable in the arcuate direction of the arrow shown in Fig. 2 by any usual beading machine control means, not shown.

A lower rotatable spindle 2| is mounted in the base I! and an upper rotatable spindle 22' is mounted in the upper head I 6, and the usual means (not shown) is provided for driving the spindles 2| and 22 at the desired speed.

Thus far, the beading machine apparatus described is of usual construction and forms no part of the present invention except in so far as it may be necessaryto adapt the same for the improved working apparatus and to form operative combinations therewith.

A thrust collar 23 and a sleeve 24 are mounted on the upper spindle 22; and special roller die parts 25, 26, and 21, also fixed on the spindle 22, are maintained in abutment against the sleeve 24 by the disk 28 and bolt 29. Rotation of the upper spindle 22 rotates the roller die parts 25, 26-and 2! which are shown as being composed of three pieces, but may be integral if desired. The part 25 is provided with a curved portion 30, an annular portion 3|, a groove 32 and a second slightly larger annular portion 33 for a purpose to be later described.

A thrust collar 34, a sleeve 35 and another collar 36 are mounted on the lower spindle 2|. A telescoping roller die is also mounted on the spindle 2| and cooperates with a spinning ring or roller die 31 and the upper roller die parts 25 2621 to work the material being formed. The telescoping roller .die includes a bushing 38, a roller die part 39, a roller die part 40 and a telescoping roller die part 4|. The parts 38, 39 and 40 are clamped tightly against the roll collar 36 by the disk 42 and bolt 43. Roller die part 39 is keyed at 44 to spindle 2| and is provided with a series of holes 45 in which are located thrust springs 46 and spring aligning pins 41.

Roll 39 drives roll 4| through sliding keys 48 which are fixed to roll 4| and slide in grooves 49 in roll 39. Roll 4| slides on bushing 38; and roll 4| is provided with a series of holes 50, matching holes 45, in which springs 46 and pins 41 are also located, so that springs 46 react between rolls 39 and 4| to constantly urge roll 4| toward collar 36. Roll 4| is provided with a curved portion 5| matching the curved portion 30 of roll 25, and roll 4| also has a tapered portion 52. Thus, roller die 25-26-21 and roller die 4| have complementary forming surfaces.

- Spinning ring 31 has a tapered face 53 matching tapered portion 52 and is mounted for vertical vertically adjustably mounted at 58 on base I1.

Springs 59 on rods 69 react between bracket 51 and ears 6| on cradle 54 to constantly urge the cradle 54 and. spinning ring 31 upward toward roll 25.

In Figs. 1 and 2, the parts are shown at the completion of a working operation whereby the receptacle blank A of Fig. 4 has been worked to proVide a bullet-nose or bottle-neck shape in the receptacle indicated at B in Figs. 1, 2 and 5.

In carrying out the working operation, receptacle B is held in alignment by suitable means, so that successive elements thereof lie in the plane of Fig. 1, which passes through the cylindrical axis of receptacle B and also through the parallel axes of spindles 2| and 22. Such means may preferably include guide rolls 62 and inside guide rolls 63. The guide rolls 62 are rotatably mounted at 64 in the lower bifurcated ends 65 of yoke 66, the upper slotted end 61 of which is slidably mounted in the center block 68 pivotally mounted at 69 on pin 19, which is carried by a bracket 1| adjustably mounted an arm 12 of the upper head or housing I6 of the beading machine.

A cross bar 13 is mounted in the upper end of the yoke 66 from which rods 14 extend upwardly; and a similar rod 15 carried by center" block 68 extends through bar 13 and carries another cross bar 16 through which rods 14 project. A series of springs 11 are mounted on rods 14 and 15 reacting between bars 13 and 16 to constantly and yieldingly urge yoke 66 downwardly.

Guide rolls 62 preferably have a curved shape, as best shown in Fig.1, to conform to the bottom radius q of the receptacle B with which the guide rolls 62 engage after a receptacle blank A has been placed on the apparatus and the upper housing moved downward. When the upper housing is so moved downward, the guide rolls 62 rest on the closed bottom end of the receptacle blank and as downward movement of the upper housing I6 continues, the top bar 16 is pulled downward by the center rod 15, thus compressing springs 11 and holding yoke 66 and guide rolls 62 under compression against the receptacle so as to firmly hold the receptacle in place and in alignment on the roller die parts carried by spindle 2|.

The small spring 18 below the center block 68, and between the-same and yoke66merely acts as a cushion. Although five springs'11 are shown, any number of springs may be used for providing the yielding, aligning and clamping pressure through the guide rolls 62 on the receptacle B.

Inside guide rolls63 may be angled slightly asindicated in Fig. 1, to accommodate a slant bottom in the receptacle B, and are. rotatably mounted at 19 on brackets 89 vertically and horizontally adjustably mounted on the cross plate 8| which is slidably adjustably mounted on the arm 82 projecting from the lower beading machine housing I1. The guide rolls 63 may have rounded comers, as shown, to conform to the inner surface'of the bottom radius a of the receptacle B.

Receptacle support or guide rolls 83 and 94 are also provided for engaging the inner open end region of the side walls of the receptacle B in order to steady the same and hold the open end substantially round during the working operation.

The roll 83 is pivotally mounted at 83 on a bracket 85, which is adjustably mounted on the bar 86 also slidably mounted on arm 82; and support roll 84 is pivotally mounted at 81 on bracket 88, adjustably mounted on bracket 89, which in turn is adjustably mounted on member 58 carried by a base I1.

Referring to Figs. 4 and 5, wherein a deep drawn receptacle blank A is shown, including cylindrical side walls I), and a bottom wall 0 joined by the curved corner a, the side walls b terminate in an outturned annular flange or shaped edge d which is quite short. In Fig. 5, the receptacle blank A has'been worked on the apparatus of Figs. 1 and 2 to provide a bullet-nose or bottleneck shape at the upper open end thereof in which the diameter of the upper open end c has been considerably reduced, while maintaining the same relatively short annular flange d at the top of a relatively deep neck f. However, the working operation has not changed the total height of the receptacle A in making the receptacle B, as shown by the dot-dash lines extending between Figs. 4 and 5.

Figs. 6 and 7 show a similar receptacle blank A with a deeper annular flange or shaped edge dd utilized to form the receptacle B with a bulletnose or bottle-neck shape at the upper end e' thereof, having a relatively long flange dd and an axially short and radially deep neck I. A

slightly modified form of roller die is required for making the receptacle Bz, as illustrated in Fig. 3, wherein spindle 22 has a roller die 99 mounted thereon by disk 28 and bolt 29. Roll 99 is provided with a curved portion 9|, a rounded annular portion 92, a deep groove 93, a second annular portion 94, which abuts against sleeve 24. Roll 99 may also be provided with a series of ribs 95 for forming annular grooves g in receptacle B.

Spindle 2| has a modified form of telescoping roller die thereon and the spinning ring is eliminated. The telescoping roller die includes a bushing 96, a roller die part 39, a roller die part 49' having grooves 49a matching ribs 95, and a telescoping roller die part 91. Another roller die part 98 having a cylindrical surface 99 and a curved surface I99 is interposed between bushing 96 and collar 36.

Parts 99, 96, 39 and 49' are clamped tightly against the collar 36 by the disk 42 and bolt 43. Roller die part 39 is keyed at 44 to spindle 2| and is provided with a series of holes 45 in which thrust springs 46 and aligning pins 41 are located.

Roll 39 drives roll 91 through sliding keys 48, which are fixed to roll 91 and slide in grooves 49 in roll 39. Roll 91 slides on bushing 96; and the recessed end I9I thereof telescopes over port-ions 99 and I99 of part 98. Roll 91 is also provided with a'series of holes 59, matching holes 45, in which springs 46 and pins 41 are located, so that springs 46 react between rolls 39 and 91 to constantly urge roll 91 toward collar 36. Roll 91 is provided with a curved portion I92 matching the curved portion 9I of roll 99, and roll 91 also has a tapered portion- I93. Thus, roller die 99 and roller die 91 have complementary forming surfaces.

The progress of the working operation is illustrated in Figs. 8, 9 and 10. Initially, the receptacle A is placed over spindle 2 I so that the bottom engages inner guide rolls 63. Upper housing I6 is then moved downward and guide rolls 62 engage, align and clamp the receptacle against the roller die parts on spindle 2| At the same time receptacle' flange d is engaged in roller die groove 32,

as best shown in Fig. 8.

Meanwhile, spindles 2| and 22 are rotated and as spindle 22 continues to move downward toward spindle 2 I while rotating, the metal in receptacle A at and adjacent to flange dis rolled, stretched, reduced and worked against spinning ring or roll 31 to reduce the diameter of the open end of the receptacle. As this working progresses, the cradle springs 59 supporting roll 31 yield radially of spindle 2|, so that ring 31 moves from the position of Fig. 8 ultimately to the position of Fig. 10. Meanwhile, spinning ring 31 is being rotatedby contact with'rotating roller die 4| and with the material being worked; and during the working, the material between spinning ring 31 and roller die part 3| is constantly under pressure between rotating roller dies.

Likewise, roller die 4 I yields axially of the spindle 2| as the working progresses and the metal is worked, stretched and rolled between die parts 30 and 5| under pressure from the position approximately that shown in Fig. 9, to that shown in Fig. 10.

The rolling, working and stretching of' the metal causes a rearrangement in the structure thereof by which the neck diameter is materially reduced and the excess metal rearranged to supply'that required for the stretched rounded portion extending between the reduced neck and the receptacle side walls. In other words, the working of the metal in and adjacent to the flange while the metal is pinched and held under pressure between the dies, simultaneously rolls the metal, increases the cross sectional length thereof, and reduces the diameter of the article to form the desired reduced neck shape, as illustrated in Figs. 8 to 10 and Figs. 11 to 13.

It has been discovered that the cold working operation described, should be carried out immediately after receptacle A has been deep drawn from a single metal blank while the material is still warm from the drawing operation. If the cold working is not performed while the metal is still warm from the drawing operation, the side walls of the receptacle A may split or crack during the cold working operation due to so-cal led age hardening. If this difiiculty is not avoided in the described manner, extra steps of pickling and annealing thereceptacle blanks are required between the drawing and working operations.

The spinning roll or ring 31 is not absolutely essential to the performance of the proper working operation, but may be used in some cases where the finished receptacle is desired to have a relatively short flange d. However, if a longer flange dd may be provided, as shown in Figs. 7

and 11 to 13, the roller die groove 93 and flange are of suflicient depth that the flange is held in groove 93 until the metal being worked in pinched between roller die 90 and yielding roller die 91. If a relatively short axial neck is desired, such as shown in Figs. 11, 12' and 13, an extra roller die 98 is preferably utilized, and at the completion of the operation, the inner portion of the neck ,1" is preferably given a final sizing and shaping against the curved roller die surface I00.

Because of the severe working operations to which the present invention subjects the metal, the receptacle side walls may spring slightly concave outwardly after the receptacle is removed from the roller dies; and for avoiding such an occurrence, the roller dies may have a slight taper provided thereon, indicated by the dot-dash lines M in Fig. 14, so that the receptacle side walls are given a slight convexity under pressure, which will permit them to spring to a substantially true cylindrical shape when the working operation has been completed.

Referring to Figs. 8 to 13, inclusive, as the working operation progresses from Fig. 8 or 11.to Fig. 10 or 13, the speed of working is preferably diminished by slowing down the rate of movement of the roller dies toward one another.

As previously stated, the telescoping roller dies on spindle 2i. yield axially of spindle 2| as the working operation progresses, by the pressure of roller die parts 30 and 3| against the rounded and tapered portions 5| and 52 of yielding roller die 4|, so that the metal is always being worked under pressure between roller dies.

Referring toFig. 2, it is understood that the particular mounting of the upper guide rolls 62 on the yoke and swivel block 68 and under tension permits the guide rolls to constantly adjust themselves as the upper head I6 moves arcuately downward. Moreover, the adjustable mounting of the various guide and support rolls permits the equipment to be adjusted to accommodate various sizes of receptacles.

The receptacle blanks A and A shown, may be some fifteen inches deep and some twenty-three inches in diameter, deep drawn from a single sheet metal blank, and the bullet-nose or bottleneck shape formed therein by the present method to produce the receptacles B or B may reduce the upper open end diameter thereof at the neck as much as three inches or more; all of which results in a new cold rolled product having such characteristics produced in a single cold rolling operation without wasting material.

It is to be understood that although a tapered bottom is shown in the receptacle B in Fig. 1, any other deep drawn formation may be provided and the guide rolls may be adjusted to accommodate the same. Moreover, although the present invention has particular importance in connection withthe formation of bullet-nose or bottle-neck shapes at the upper open ends of closed bottom sheet metal receptacles such as washing machine tubs drawn from a single metal blank, it is clear that the improved cold working operation may be used in connection with performing a similar operation upon tubular sheet metal material.

'It is not intended to limit the scope of the present invention to the particular bullet-nose or bottle-neck shapes shown herein because it is clear that other shapes may be made in accordance with the improved method by utilizing roller dies having the desired shape. Nor is it intended to limit the scope of the present invention to a method of making receptacles used solely as tubs for washing machines, because it is clear that other vessels or containers having substantially reduced necks or openings may be made in accordance with the improved method.

Moreover, the term sheet metal used herein and in the appended claims, is intended to refer to sheet or strip or plate metal of the desired composition and ductility according to the source, composition and thickness of the material utilized.

Accordingly, the improved method and apparatus provides aninexpensive way of making bullet-nose or bottle-neck formations in tubular or cylindrical sheet metal articles, without wasting material by a cold working process, and accomplish'es the objectives and avoids the difliculties previously set forth herein.

We claim:- e

1. The method of forming a reduced neck at an end of a cylindrical sheet metal article which includes the steps of forming a flange at an end of such article, holding the article in alignment between rbller dies one of which is axially yieldable, and roller working metal in and adjacent to said flange by rotating the dies and moving the axes thereof relatively toward one another to cause said axially yieldable die to yield while pinching and holding the metal under pressure between the dies where the working is being performed; which roller working between yielding dies simultaneously increases the cross sectional length of the metal, and reduces the diameter of the article in and adjacent to the flange to form the desired reduced neck shape.

2. The method of forming a reduced neck at an end of a cylindrical sheet metal article which includes the steps of deep drawing a cylindrical article, forming a flange at an end of said article, cold roller working the metal in and adjacent to said flange between roller dies one of which is axially yieldable by rotating the dies and moving the axes thereof relatively toward one another to cause said axially yieldable die to yield while pinching and holding the metal under pressure between the dies where the working is being performed, and performing said working operation while the article is still warm from the drawing operation; which roller working between yielding dies simultaneously increases the cross sectional length of the metal, and reduces the diameter of the article in and adjacent to the flange to form the desired reduced neckshape. I

3. The method of forming a flanged reduced neck at an end of a cylindrical sheet metal article which includes the steps of forming a flange at an end of such article, holding the article between roller dies one of which is axially yieldable, and roller working the metal in and adjacent to said flange by rotating the dies and moving the.

axes thereof relatively toward one another to cause said axially yieldable die to yield whfle pinching'and holding the metal under pressure between the dies where the working is being performed; which roller working between yielding dies simultaneously increases the cross sectional length of the metal in and adjacent to the flange and reduces the flange diameter. g v

4. The method of forming a'flanged reduced neck atan end of a deep drawn cylindrical sheet metal blank having a flange at the end. thereof without altering the over-all length of such blank which includes the steps of holding the blank between roller dies, holding the blank flange and the other extremity thereof, to maintain the same a constant distance apart, and working the metal in and adjacent to said flange by rotating the dies and moving the axes thereof relatively toward one another while pinching and holding the metal under pressure between the dies where the: working is being performed; which working simultaneously rolls the metal, increases the cross sectional length thereof, and reduces the flange diameter to form the flanged reduced neck shape.

5. The method of forming a reduced neck at an end of a cylindrical sheet metal article which includes the steps of forming an outturned flange at an end of such article, holding the article be-' tween roller dies, holding the extremities of the article in fixed planes a constant distance apart perpendicular to the axes of the dies, and working the metal intermediate the extremities of the article and in and adjacent to said flange by contacting the roller dies with the article and rotating the dies to rotate the article while pinching and holding the metal under pressure between the dies where the working is being performed; which working simultaneously rolls the metal, increases the cross sectional length thereof, and reduces the flange diameter to form the desired reduced neck shape.

6. The method of forming a reduced neck at an end of a cylindrical sheet metal article which includes the steps of deep drawing a cylindrical article, forming an outturned flange at an end of said article, cold roller working the metal in and adjacent to said flange between roller dies one of which is axially yieldable by rotating the dies and moving the axes thereof relatively toward one another to cause said axially yieldable die to yield while pinching and holding the metal under pressure between the dies where the working is being performed, performing the working operation while the article is still warm from the drawing operation, and slowing down the rate of movement of the axes of the rotating dies relative to one another as the working operation progresses; which roller working between yielding dies simultaneously increases the cross sectional length of the metal in and adjacent to the flange and reduces the flange diameter,

'7. The method of forming a reduced neck in the walls of a cylindrical article at an end thereof, which includes the steps of forming an outturned flange at an end of such article, holding the article between roller dies one of which is axially yieldable, and roller working the metal in and adjacent to said flange by rotating the dies and moving the axes of the rotating dies relatively toward one another to cause saidraxially yieldable die to yield while pinching and holding the metal under pressure between the dies where the working is being performed; which roller working between yielding dies simultaneously reduces the diameter of the article in and adjacent to said flange, and increases the cross sectional length of the metal adjacent to, said flange as the same is being worked to form the desired reduced neck metal which includes the steps of forming an outturned flange at the open end of the receptacle, holding the receptacle between roller dies one of which is axially yieldable, and roller working the metal in and adjacent to the flange by rotating the dies and moving the axes thereof relatively toward one another to cause said axially yieldable die to yield while pinching and holding themetal under pressure between the dies where the working is being performed; which roller working between yielding dies simultaneously increases the cross sectional length of the metal and reduces the diameter of the receptacle in and adjacent to said flange.

9. The'method of forming a bottle-neck shape at the upper end of a closed bottom sheet metal receptacle deep drawn from a single blank of metal which includes the steps of forming an outturned flange at the open end of the receptacle, holding the receptacle in alignment on one of a plurality of roller dies one of which is axially yieldable by 'yieldingly clamping the side w-lls of the receptacle adjacent to the closed bottom against said flrst mentioned roller die, and roller working the metal in and adjacent to said flange by rotating the dies and moving the-axes thereof relatively toward one another to cause said axially yieldable die to yield while pinching and holding the metal under pressure between the dies where the working is being performed; which roller working between yielding dies simultaneously increases the cross sectional length of the metal and reduces the diameter of the receptacle in and adjacent to said flange.

10. The method of forming a bottle-neck shape at theupper end of a closed bottom sheet metal receptacle deep drawn from a single blank of metal which includes the steps of forming a flange at the open end of the receptacle, holding the receptacle between roller dies one of which is axially yieldable, supporting the open end of the receptacle between rollers to hold the same in substantially cylindrical shape, and roller working the metal in and adjacent to said flange by rotating the dies and moving the axes thereof relatively toward one another to cause said axially yieldable die to yield while pinching and holding the metal under pressure between the dies where the working is being performed;

' which roller working between yielding dies simultaneously increases the cross sectional length of the metal and reduces the diameter, of the receptacle in and adjacent to said flange.

11. The method of forming a bottle-neck shape at the upper end of a closed bottom sheet metal receptacle deep drawn from a single blank of metal which includes the steps of forming a flange at the open end of the receptacle, holding the receptacle between roller dies one of which is axially yieldable, maintaining the flange and receptacle bottom a constant distance apart, and roller working the metal in and adjacent to said flange by rotating the dies and moving the axes thereof relatively toward one another to cause said axially yieldable die to yield while. pinching and holding the metal under pressure between the dies where the working is being performed; which roller working between yielding dies simultaneously increases the cross sectional length of the metal and reduces the diameter of the receptacle in and adjacent. to said flange.

12. The method of forming a bottle-neck shape at the upper end of a closed bottom sheet metal receptacle deep drawn from a single blank of metal which includes the steps of forming a flange at the open end of the receptacle, holding the receptacle between roller dies one of which is radially yieldable, maintaining the flange and receptacle bottom a constant distance apart, and roller working the metal in and adjacent to said flange by rotating the dies and moving the axis of one relatively toward another to cause said radially yieldable die to yield while pinching and holding the metal under pressure between the dies where the working is being performed; which roller working between yielding dies simultaneously increases the cross sectional length of the metal and reduces the diameter of the receptacle in and adjacent to said flange.

13. The method of forming a bottle-neck shape at the upper end of a closed bottom sheet metal receptacle deep drawn from a single blank of metal which includes the steps of forming a flange at the open end of the receptacle, holding the receptacle between roller dies one of which is axially yieldable and another of which-is radially yieldable, maintaining the'flange and receptacle bottom a constant distance apart, and roller working the metal in and adjacent to said flange by rotating the dies and moving the axis of one relatively toward the axis ofanother to cause said axially and radially yieldable dies to yield while pinching and holding the metal under pressure between the dies where the working is being performed; which roller working between yielding dies simultaneously increases the crosssectional length of the metal and reduces the diameter of the receptacle in and adjacent to said flange.

14. The method of forming a flanged reduced neck joined integrally by a curved wall portion with the side walls of a closed bottom sheet metal receptacle deep drawn from a single blank of metal which includes the steps of forming a flange at the open end of the receptacle, holding the receptacle'between roller dies one of which is axially yieldable, maintaining the flange and receptacle bottom a constant distance apart, and roller working the metal in and adjacent to the flange by rotating the dies and moving the axes thereof relatively toward one another to cause said axially yieldable dies to yield while pinching and holding the metal under pressure between the dies where the working is being performed; which roller working simultaneously reduces the flange diameter and forms the reduced neck, and increases the cross sectional length of the metal adjacent to the flange to form the curved wall between the reduced neck and the receptacle side walls.

15. The method of forming a reduced neck at an end of a cylindrical sheet metal article which includes the steps of forming a flange at an end of such article, holding the article between roller dies, engaging and holding the flange in a fixed plane, and working the metal in and adjacent to said flange by rotating the dies and moving the axes thereof relatively toward one another; which working simultaneously rolls the metal, increases the cross sectional length thereof, and reduces the diameter of the flange and of the material adjacent to the flange to form the desired reduced neck shape.

16. Apparatus for cold working a sheet metal article having a flange at one end thereof including a plurality of roller dies, means for rotating the dies, a groove in one of said dies for holding said flange in a fixed plane during working, means for moving the axes of the roller dies toward and away from one another, and yielding means mounting one of the roller dies for axial movement from the pressure of another roller die.

17. Apparatus for cold working a sheet metal article including three roller dies having parallel axes, means for rotating the dies, means for radially moving one of said dies radially toward a second to grip an article therebetween and thereafter for moving radially the two dies in unison, yielding means mounting the third die for axial movement, said first and second dies in their radial movement working the article adjacent the third die, and said third die moving axially during said last mentioned working.

18. Apparatus for cold working a sheet metal article including three roller dies having parallel axes, means for rotating the dies, means for radially moving one of said dies radially toward a second to grip an article therebetween, yielding means mounting said second roller die for radial movement in unison with the first die after the article has been gripped therebetween, yielding means mounting the third die for axial movement; said first and second dies in their radial movement reducing the diameter of the article by pressure working adjacent the third die, and said third die moving axially during said last mentioned working.

19. Apparatus for cold working a sheet metal article having a shaped edge at one end thereof including a plurality of roller dies having parallel axes, means for rotating the dies, a groove movable die moving axially during said working.

20. Apparatus for cold working a sheet metal article having a shaped edge at one end thereof including a plurality of roller dies for working the article at and adjacent to said shaped edge, means for rotating the dies, said dies including means for holding said shaped edge in a fixed plane perpendicular to the axes of said roller dies during working, means for moving the axes of the roller dies toward and away from one an- 7 other, and yielding means mounting one ofthe roller dies for axial movement from the pressure of another roller die during working.

21. Apparatus for cold'working' a bottle neck at the top of a closed bottom cylindrical sheet metal article including a plurality of roller dies for working the article at and adjacent to the top thereof, means for rotating the dies, means for holding the extremities of the article in fixed planes perpendicular to the axes of the roller dies spaced a constant distance apart during working, means for moving the axes of the roller dies toward and away from one another, and yielding means mounting one of the roller dies for axial movement from the pressure of another roller die during working.

22. Apparatus for cold wo-rkinga closedbottom cylindrical sheet metal article having a shaped edge at the open end thereof including a plurality of roller dies for working the article at and adjacent to said shaped edge, means for rotating the dies, means for moving the axes of the roller dies toward and away from one another, yielding means mounting one of the roller dies for axial movement from the pressure of another roller die during working, a plurality of guide rolls engaging cylindrical portions of said article at places spaced from each other and from the dies and the portion of the article being worked for holding the article in alignment between the dies during working, a plurality of 'support rolls engaging cylindrical portions of the means for moving the axes of .the roller dies toward and away from one another, yielding means mounting one of the roller dies for axial movement from the pressure of another roller die during working, said dies including means for holding said shaped edge in a fixed plane perpendicular to the axes of the roller dies, means for holding the other extremity of the article in an other fixed plane perpendicular to the axes of the roller dies and spaced a constant distance from the first said plane during working, and means engaging the article at placesspaced from each other and from the dies for supporting, holding and maintaining the article in alignment between the dies and in cylindrical shape during working.

24. The method of forming a reduced neck at an end of a cylindrical sheet metal article which includes the steps of shaping an edge at an end of such article, and Working the metal in and adjacent to said shaped edge under pressure between roller dies by rotating the dies and moving the axes thereof relatively toward one an other; which working simultaneously rolls the metal, increases the cross sectional length there'- of, and reduces the diameter of the shaped edge and of the material adjacent to said shaped edge.

JOHN W. FRENCH. JOHN O. E. CARLSON.

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