SWAGING MACHINES. Figs. 1, 2, and 3 represent the Dayton swaging machine. as used by the Excelsior Needle Co., at Torrington. Conn., for the swaging of needle blanks. It contains a revolving shaft having across its end a mortise or groove, and a pair of sliding (lies. Around this is arraAged a cylindrical shell, and there are rollers be.
t ween the dies and the shell, having their axes in ring bearings, so as to roll around within the shell by the action upon them of the dies. The ends of the dies come into contact with the rollers successively, and these being at opposite sides within the shell, act as rolling toggles to press the dies together. In this manner there are as many closures of the dies at each revolution of the shaft as there are rollers in the circular range, and the parts are constantly in motion, so that there is an extended wearing surface on the in terior of the shell and the exterior of the rollers. Hence the apparatus is very able, and there is but little friction of the parts. The partial sections represent enlarged views of the dies and of the grooved shaft. The dies fitted in the groove are double— that is to say, there is a die face at each end of the blocks, C C, and there are follow ers, C' C, against the rounded ends of which the rollers, ll, act in the swaging operation. When the die faces in the center are worn they are resurfaced and rebored, and it be comes necessary to use filling pieces to com pensate for the metal removed. These filling pieces or shims, which may be of any con venient thickness or numher, are placed be tween the blocks, C and C. The die blocks having faces at both ends allow of their being turned end for end and used for a longer period without requiring to be resurfaced and bored. The dies and rollers do not slide on one another, but the contact is a rolling move ment. Iience, there is but little friction, and the power is expended to the best advantage in compressing the article that is placed between the dies, thereby cold swaging the same, so as to reduce a wire to a needle blank, or to straighten or point wires or rods, or to straighten and render rods or shafts uniform in size. The main casting, B, is fittte-d with a steel ring, 11, against which the rollers, R, bear. These rollers are mounted and turn on spindles, the ends of which are cut down so as to fit in narrow slots cut in the ring bearings. 0 and 0'.
The manner in which this is accomplished is clearly shown. There are eight rollers in this case, though there may be more or less. The rollers roll upon the interior surface of the ring. II; and the ends of the dies, C' C. as they are revolved. come into contact with the rollers in succession. and act to turn such rollers progressively, and each roller forms a toggle between the interior surface of the shell and the end of the die. The latter is closed to the full extent when the center of the die is in a radial plane passing through the axis of the roller with which the die is in contact. The shaft, 4, is tubular for the passage of the wire, rod, shaft, or bar that is operated on, and its grooved portion is of enlarged diameter. If the shaft is revolved by the pulley, the article to be acted upon will only require to be fed in gradually, and be free to be revolved by the action of the dies as they move slightly while grasping the work.
In Fig, 2, D I) are screws passing through a plate secured to the face of the shaft, The points as shown project into enlarged holes in the blocks, Cr, and limit the extent of outward motion of these. outside ring, F, is screwed to the casting, B, making the machine ready for work. Where two dies are used there must be an even number of rollers, so that they act at opposite sides of the shell. Three-die machines built on the same prin ciple require 6, 9, or 12 rollers, the dies being placed at angles of 120'. Near the bottom of Fig. 2 is shown a specimen of work done in the machine—a drawn-down sewing-machine needle blank. Comparison of the lower with the upper of the two engravings, which latter represents the blank originally, shows that the whole amount of metal in the elongated por tion corresponds to that embraced between the lines, a b, The diameters of the blank orig inally and of the drawn-down portion are and 0.012 in. respectively. At the works of the Excelsior Needle Co. a number of the machines are engaged exclusively in the swaging of sewing-machine needle blanks, though obviously they are applicable to a variety of other work. Machines of larger size arc used for pointing rods preparatory to drawing into wire, and also for working in iron steel in various lines of manufacture.