US1688175A - Forging balls from long bars - Google Patents

Description

Oct 16, 1192s. 1,688,175

A. CANDA FORGING BALLS FROM LONG BARS Filed Aug. 17, 1925 3 Sheets-Sheet 1 mmvroze JflbeeZ Oanda By mG@9'b1Qm 1 ATTORNEY 3 Sheets-Sheet 2 ////////////I//V////////4 p l i IN VE N TOR ATTORNEY A. CANDA EORGING BALLS FROM LONG BARS Filed Aug..l7, 1925 Oct. 16, 1928.

B 29662 C a/vzda/ Patented Oct. 16, 1928.

UNITED STATES 1,688,175 PATENT OFFICE,

ABEEL CANDA, F CRALN'FORD, NEW JERSEY.

.FORGING BALLS FROM LONG BARS.

Application filed August 17, 1925 Serial No. 50.879;

My invention relates to a method'of forging balls, slugs, discs and the like, from long bars or rods and to apparatus for carrying out this method.

In forging balls from long bars, the finished balls are necessarily of greater diameter than the bars and consequently the metal must flow from the ends of the ball element toward the center and must be subjected to the proper pressures during the shaping process in order to prevent flaws in the finished product. "When the balls are formed in substantially circular grooves extending around the circumference of a cylindrical drum, the grooves must have the same uniform contour throu h their extent, the shaping of the balls belng effected by gradually narrowing the width of the pass.

I have found that it is practically impossible to form perfect balls free from creases and other flaws by this method. Accordingly, I have devised a method by which the metal progresses contin'uousl channels of varying s apes in which the metal is subjected to a kneading action which causes .the metal to more readily flow into the deeper parts of the grooves and prevents the formation of internal flaws, producing a compact homogeneous mass. During the first stage of the process the bar is graduallyflsheared along its. length into billets, the metal being caused to flow toward the ball I centers while the bar is rotated upon its axis. When the bar is nearly severed the ball elements are moving in a narrower ass between the two rolls, the pass being slig tly flattened which causes the stock to take a spiral movement sufficient to break the connecting necks and the separate ball elements then take a spiral movement between the grooves which forges out the central peripheral ring left between the metal that has moved up into the groove from opposite ends of the elements. At this stage the billet or ball element has been shaped to form a double cone with their bases together. From this point the elements are subjected to the action of round grooves which shape them into true spherical form.

The object of my invention, therefore, is to provide a method of forming s herical balls free from flaws by subjecting t e stock to forming grooves having a spiral path and varying in shape from one portion of the I groove to another portion.

through grooved which cut deeper and deeper until the bar is nearly severed into billets to form the ball In the following description of an apparatus for carrying out this method I shall refer to 1 the accompanying drawings, in which Figure 1 is a top plan view partly in section, of a machine embodying the features of my invention; Figure 2 is an end elevation of the same; Figure 3'is a central vertical longitudinal sectional view of the same; Figure 4 is a fragmentary sectional View showing the arrangement of the guide for directing the stock between the rolls; Figures 5 and 6 are diagrammatic views showing the shapes of the passes at various stages through the machine; and Figure 7 is a transverse sectional view showing the manner of applying this invention to a plurality of grooved rolls operating simultaneously upon a plurality of stock bars.

For the purpose of carrying out the method above outlined, I provide a machine having coacting rolls 10 and 12, provided with helical grooves into which the stock bars 14 are fed endw'ise, through a bushing 15, the completed balls being delivered at the'opposite end of the rolls into the chute 16. The stock is fed to one side of the center line of the coacting rolls, instead of on thcenter line as heretofore, the pressure exerted by the rolls causing the stock to bear against the guide or stop member 19. The stock bar is thus subjected to a three-cornered pressure as it moves through the pass between the two rolls and the guide member, this triangle of forces eliminating the possibility of tearing the metal as it is being forged into vballs or slugs.

During the first stage of the process it is necessary that the metalbar should be sheared progressively by the ribs of the rolls,

elements. I have found that the cutting or shearing action takes lace more efliciently when the ribs 20 are s arp and V-shape as' shown in Figure 5. The shape of the V- shaped shearing ribs'together with the fact that the billets are still connected by narrow necks causes them to rotate on the axis of the bar and the spiral grooves exert a kneading action upon opposite sides, indicated by the shaded edges, and this assists in causing I ill-3h?l metal to flow toward the center of the i et.

I have indicated in Figure 3 the heated stock bar being fed through the bushing 11o below the axis of the ions and showing the action of the rolls on the stock as it progresses-tlirough the machine, By the time it has moved from one quarter to one third of the distance through the machine, the billets or ball elements have been severed and they then partake of a spiral movement. At this stage the stock has not entirely filled the grooves but has left a central ring or groove g, which has not filled'up, as indicated in Figure 5. The billets being now independent of each other, partake of a spiral movement and rotate on an anis'diagg nal to the axis of the pass.

As the ribs 20 cut deeper and deeper into the stock, the displaced metal is caused to flow back into the recesses 23. Heretofore these have been V-shape, the sides of the re cess being continuations of the sides of the ribs 20 in the same plane. This permitted the metal flowing into a recess to form a ridge upon opposite sides of the recess and it was necessary for these ridges to be rolled down into the body of the billet in the later stages after the billets are severed from the stock bar. I have overcome this "formation of ridges by rounding or curving the walls 23 of the channels. This also contracts the space 23 and the flowing metal follows the rounded wall 23*, nearly filling the space and without any pronounced protuberances.

By the time the billets reach the central point in the machine, the slight groove-has been eliminated and they then enter the round grooves forming the latter half of the spiral path. The width of the pass is gradually narrow-ed until it is the diameter of the finished ball. Each ball part-akes of a spiral movement, its axis rotating about an orbit indicated at o-c in Fig. 6. As the ball eleb d1 ments traverse this finishing portion of the pass they are rolled into perfect spheres.

The grooved shells are fitted over and geared to rotate at the same speed. The

bearings, of course, are movable so that proper adjustment can be made for the'si ze of the pass and also to compensate for the wear of the grooves.

In prior machines employing spirally grooved rolls, each roll is formed ,wit a single continuous spiral groove while in my machine, I provide the rolls with a plurality of spiral grooves. Thus in a. machine havmg rolls 26 inches in diameter, and with a lead angle of about 30 de ees in the spiral, there are 22 grooves. lfia nce there are 22 different channels, which pass the inlet bush- 1,ee e,175

ing 15 through which a rod is fed durin each revolution of the drum into any one 0 which the rod may be inserted. This of course, greatly increases the life of the roll andfurthermore enables me to combine a number of such rolls in a, machine, as indicated in Figure 7, so that a plurality of rods may be-operated upon .simultaneously.

"I have described particularly the method of forming balls'or spherical bodies, but it will be obvious to engineers that this ma chine may be readily adapted to use for making non-spherical objects, such as slugs, discs and the like.

erted, the metal is subjected to a forging action which thoroughly kneads the metal and, eliminates all internal flaws and-yet without anydanger of tearing the metal.

, I claim 1. A. method of forging balls, which consistszin axially rolling a heated metal bar and grooving it progressively from one end into a connected series of elements'which each have a configuration of, two frusto-conical surfaces joined at their bases by a cylindrical surface, subjecting the metal to a kneading 'action by a plurality of centripetal pressures and resisting said pressures by an oppositely directed resultant centripetal pressure, severing the metal at the grooves into separate elements, subjecting the elements to a spiral rolling motion and sumultaneously compactingand shaping them into true spherlcal 0 es. I

2. A'machine for forming balls from a heated rod or bar, comprising a pair of oppositely rotatable rolls having coacting Splral grooves, the ribs'formed at the intersection of the grooves being arranged to pro-- gressively cut into the metal until the metal is severed into separate elements within the grooves, a stationary member extending parallel to the axes of the rolls at one side of a diametrical plane passing through the axes of the rollsand acting to resist the centripetal pressures exerted upon the metal by the rolls, and meeting with the grooves of the rolls to subject the metal to a kneading action and the severed elements to a spiral rolling motion thereby simultaneously com- CANDA.

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