(No Model.) 3 Sheets-Sheet 1.
- A. HARVEY.
MACHINE FOR ROLLING SGREWS.
Patented Feb. 1, 1887.
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(No Model.) Q 3 Sheets-Sheet 2.
H. A. HARVEY.
MACHINE FOR ROLLING SCREWS. No 357,002. Patented Feb. 1 1887.
N, PEIERS. Phmo-Uthsgnvhor, Wahlngian. or.
(No Model.) a sn ets eeeee 3.
H. A. HARVEY.
MACHINE FOR ROLLING SCREWS.
Nbpssmooz. T Patentedfeb. 1, 1887.
1 UNITED STATES PATENT OFFICE.
HAYWARD A. HARVEY, OF ORANGE, NEW JERSEY.
i MACHINEFOR ROLLING SCREWS.
SPECIFICATION forming part of Letters Patent No. 357,002 datedFebruary 1, 1887.
' Application filed November 23, 1886. Serial No. 219,642. (No model.)
TOaZZ whom i1; may concern:
of Orange, New Jersey, have invented certain Improvements in Machines for Rolling the Threads of Screws and Bolts, of which the following is a specification.
' These improvements relate to the type of machines in which the threads on screws and bolts are formed by thesubjection of the screwblank or bolt-blank to the action of two reciprocatingv dies, the faces of which are suitably ribbed, and which, by their motions in rectilinear paths in relatively opposite directions,
roll the screw-blank or bolt-blank to and fro and gradually impress a spiral groove upon its In machines of this type heretofore invented the formation of the spiral groove that the thread when formed was made to ex-" in the body of the blank has been accompanied by a radially outward flow of the metal displaced in forming the groove, with the result ceed' in its outside diameter the original diameter, of the blank.
The object of the present invention is to cause the whole or nearly the whole of the metal which is displaced during the formation of the spiral groove in the body of the blank .to flow in a direction parallel with the axis of 'straight dies having opposed convex faces axis.
and means for imparting to each'of said dies duringits endwise movement, while the screwthread is being formed, a prescribed range of slow rocking movement upon its longitudinal The faces of the dies, respectively, are provided with series of oppositely-inclined parallel ribs, and, if desired, portions of their faces adjoining those portions which are convexly curved may be oppositely curved, to
adapt them for forming a gimlet-point upon the end of the screw-blank subjected to their action. The range of rocking movement for the dies is graduated with reference to enabling the dies to form successively a prescribed number of convolutions of thread upon the body of the blank upon which they are to act. Be it known that I, HAYWARD A. HARvEY,
Incidentally these improvements embrace certain peculiarities in the mechanism for antomatically feeding the blanks successively to the dies. l
The accompanying drawings of a machine 2 embodying'the improvements are as follows:
Figure l is a top view. Fig. 2 is a longitudinal vertical section through the line as as on Fig. l.' Fig. 3 is an end elevation showing the mechanism for imparting the rocking motions to the dies. Fig. 4 is a transverse vertical section through the lineyyon Fig. 1. Fig. 5 is a rear elevation. Fig. 6 is a side elevation, partly in section, of the mechanism for delivering the blanks successively, showing the deliverer in the position in which it comes to rest at the close of its backward movement in the act of delivering a blank. Fig. 7 is a similar view showing the deliverer in the position in which it comes to rest at the conclusion of its forward movement. Fig. 8 is a top view,of the deliverer and adjoining parts of the machine. Fig. 9 is a transverse vertical section of the reciprocating rocking dies,showing the positions which they occupy relatively to each other and to the blank at the commencement of the operation. Fig. 10 is a similar section of the dies, showing their positions relatively to each other and to the blank just before the conclusion of the rolling operation 7 The workingparts of the machine are mounted upon a horizontal rectangular table, A,- supported at its opposite ends upon the standards A A The table is provided with suitable slots to afford clearance for the mov able parts 'of the machine.
Power to drive the machine isapplied to the horizontal driving-shaft B,having its bearings,
respectively, in boxes B B Upon its inner end the driving-shaft is provided with a crankarm, 0, which is linked by means of the pitman 0 to a collar, C, which is loosely hung upon the forward end of what, for the sake of convenience,will be herein called the stem D of the quick-moving die D. The collar (J is loosely hung upon the stem D in order to permit the die D to rock upon its longitudinal axis. The die D" is somewhat larger in diameter than the stem D,and its bearing is a semicylindrical groove, the lower half, cl,of which is formed 'in the table and the upper half, d, in the cap (Z The driving-shaft B has affixed to it the small spur-wheel b, which engages the gear b, affixed to the counter-shaft E, provided with bearings in the boxes E E". The gears are relatively of the necessary diameters to cause the counter-shaft to make one revolution while the driving-sl1aft is making two,thrce,or more revolutions,asmaybe prescribed. The countershaft has aflixed to it the scroll-cam c, which engages the end of the sliding cam bar 6 and imparts backward movement thereto, the forward movement of the cam-bar being effected by the retracting spiral spring 0, The cam-bar catits back end is hung on thecrankpin f, which is adjustably secured to the radially-slotted cranlearm f of the rocking camshaft F.
The cam-shaft F carries the scroll-cam F, which acts upon the lower 'end of the rocking lever F the upper end of which bears upon the back end of the stcm G of the slow-moving die G.
The die G, like the die D, is a cylinder of larger diameter than its stem, and is provided with a semi-cylindrical bearing,the lower half, 9, of which is formed in the edge of the laterally-adjustable plate H and the upper half,g, in the edge of the cap H, secured to the plate H. The plate H is supported upon the horizontal bed of the machine, and is adjusted thereon toward and from the die D by means of the horizontal adjusting-bolt 71, and is rigidly secured in the position to which it may have been adjusted by means of the jam-screws h h,which are provided with large collars, and are inserted through holes in the plate H into the bed upon which the plate rests, the holes in the plate H being made large enough to provide for the required range of adjusting movement of the plate H.
Rocking movements are'imparted to the dies by means of the cams I and K, affixed to the rocking cam-shaft F. These cams engage the lower ends of the crank-arms I and K,which are affixed by means of set-screws to the sleeves I and K, having their bearings, respectively, in the horizontally-adjustable box I and in the upper part, K, of the end standard, A The sleeves I and K" are loosely splined upon the stems D and G of the dies D and G, respect ively.
By the appropriate rocking movement of the scroll-cam F slow endwise movement is imparted to the die G, which continues duringaprescribed number of backward and forward endwise motions of the die D. The return movement of the slow-moving die G is effected by the retracting spiral spring F The forward end of the stem G is looselyinserted through the vertical arm Zof the check and deliverer carriage L. A screw, Z, is inserted in the end of the stem G, and the edge of the head of this screw bears upon the face of the arm Z. Thus the carriage Lis compelled to partake of the endwise sliding movements of the die G.
The mechanism for automatically feeding the blanks successively to the dies embraces the inclined ways M, down which the blanks, hanging by their heads, slide by their own gravity, their descent being checked during the first portion of the forward movement of the die G by the bearing of the lowermost blank against the side of the deliverer N, which at that time extends across the lower end of the inclined ways. a The deliverer N is a flat bar set up edgewise and provided with horizontal bearings in the carriage L. As the die G moves gradually forward, pushing forward the carriage L, the check-arm m affixed to the carriage L, is projected across the ways between the lowermost blank and the blank next behind it, and serves to hold back the row of blanks in the ways when the deliverer has been carried forward clear of the lower end of the inclined ways. The lowermost blank then slides downward into the forward end of the horizontal portion M of the ways, where it stands in front of the end of the deliverer.
It is necessary that the deliverer shall have a greater range of forward movement than the die G, in order that it may be carried so far forward as to allow the lowermost blank to drop in front of it. This is effected by means of the rocking lever 41, which, by means of the pin a, is pivotallyaffixed to the carriage L, and has its upper end loosely engaged in the notch a, formed in the edge of the deliverer N. The lower end of the rocker a projects into arectangular notch formed in the edge of the adjustable horizontal gagc-plate O, which is affixed to the table, as shown in Figs. 7 and S, and is capable of adjustment thereon in a direction parallel with the path of motion of the carriage L.
\Vhen the die G and carriage L have been carried sofar forward as to effect the partial projection of the check-arm on across the ways, the lower end of the rocker n is brought into collision with the forward edge, 0, of the gage-plate, and is thereby made to rock upon its axis, and by the engagement of its upper end with the deliverer N to impart such an increased range of forward movement thereto as to withdraw the front end of the deliverer from the space at the lower end of the inclined ways, thus, as before stated, permitting the lowermost blank to drop into the horizontal part of the ways immediately in front of the deliverer. Duringthequickreturn movement of the die G the deliverer is carried backward across the lower end of the inclined ways, pushing the blank before it toward the space between the dies D and G. As the carriage L moves backward, thelower end of the rocker n is brought into collision with the rear edge, 0 of the gage-plate, and,being thus compelled to rock upon its axis in a direction opposite to that in which it has previously rocked, imparts an increasedrange of backward movement to the deliverer and carries the blank against the slightly-chamfered edge G of the die G. The blank arrives at this position concurrently with the arrival of the die G at its farthest backward position. When the die G and the blank are in this posit-ion, the quickmoving die D is in its extreme forward position, and is just ready to commence its backward movement. By the backward movement of the die D its back edgeis carried into collision with the body of the blank, which is thereby caught and rolled along the surface of the die G. While the blank is being rolled along the face of the die G the latter is making a portion of its forward movement, so that during the return or forward movement of the die D the blank will not be rolled far enough backward to clear the-forward end of the-die G. The blank is rolled to and fro along the face of the die G as many times as the die D reciprocates during the slow forward movement of thedie G, and at the last backward movement ofthe die D the blank is rolled off the back end of the die G.
It will be understood, of course, that the die G is herein called the slow-moving die merely for convenience of distinguishing it from the die D, whichreciprocates two or more times while the die G reciprocates once.
The working portions of the faces of the dies D and G are each provided with systems of parallel ribs extending spirally along the faces of the dies in respectively opposite, di-
During thetoand-fro rolling movements imparted to the blank the dies are gradually rockingupon their longitudinal axes, and the convolutions of the thread are thus being successively formed upon the body of the blank.
When the machine is to be used to roll the threads of machine'screws, the working-faces of the dies are made concentric, respectively, with the axes upon which they rock; but if the dies are to beadapted for rolling the threads of gimlet-pointed screws, the dies are respectively provided with the concentric portions 1? and p, which are each provided with the systems of parallel ribs which are to form the thread of the body of the blank, and are also provided with the projecting portions 1? p, inthe faces of which are formed ribs for acting upon the end of the blank and forming the gimlet-point, as shown in figures.
It will be seen that the convolutions of the thread of a blank are in this machine formed successively, instead of being formed simultaneously, as they are where the blank is rolled between the opposed faces of two flat dies, which act simultaneously upon the entire portion of the body which is to be threaded.
By this organization of the feeding mechanism the necessity of employing a cam for oper ating the check is obviated, for, as will be seen,
the motions of the check and deliverer are herrowed from the slow-moving die G.
What is claimed as the invention is- 1. In a machine for rolling the threads of screws or bolts, two endwise reciprocating and rocking dies, the opposed faces of which are suitably curved, and are provided with systems of parallel ribs extending spirally in relatively opposite directions, respectively, means for imparting to one of the said dies two or more to-and-fro endwise movements during the time occupiedin rolling the thread upon a blank introduced between the dies, means for imparting tothe other die one toand-fro endwise movement during the same time, and means for imparting during the same tim'e'to each of the said dies, first, a prescribed range of slow rocking movement upon its longitudinal axis in one direction while the thread is being formed upon, the blank, and then a quick return rocking movement in the opposite direction after the threaded blank has been discharged, and while the dies are making their concluding movements by which they reach the relative positions which they are required to occupy preparatory to the feeding of another blank into the space between their working-faces.
2. The combination, substantially as set forth, of the endwise reciprocating and rocking dies D and G, provided, respectively, with the stems D and G, the crank-arms 1 and K, loosely splined upon the said stems, respectively, two suitably-shaped cams engaging the ends of the crankarms I and K, re
,spectively, and mounted upon the camshaft F, and means for appropriately movingthe cam-shaft F, and thereby rocking the dies D and G upon their longitudinal axes during their endwise-reciprocating movements.
3. The combination, as set forth, of the die G, the retracting-spring F the scroll-cam F, mounted upon the cam-shaft F, the rocking lever F hearing at one end upon the scrollcam' F and at the other end upon the end of the stem G of the slow-moving die G, and means for appropriately moving the cam-shaft F, and thereby imparting the required endwise-reciprooating movements to the die G.
4. The combination, as set forth, of the cam e, mounted upon the counter-shaft E, the cambar e, the retracting spiral spring 6, the. crank-arm f, the crank-pin f, adjustably secured to the I crank-arm f, and the rocking cam-shaft F, having mounted upon it suitable cams for imparting rocking movements to the dies D and G, respectively.
5. The combination, as set forth, of the endwise-reciprocating die G', the carriage L, the deliverer N, provided with sliding bearingsin the carriage L, the ways M M, and the endwise-reciprocating die D.
6. The carriage L, suitably connected with and partaking" of the endwise-reciprocating motions of the die G, the deliverer N, provided with sliding bearings in the carriage L, the rocking lever a, pivotally affixed to the carriage L and at its upper end engaging the deliverer N, in combination with the horizontally-adjustable gage-plate O, for catching the lower end of the rocking lever it during the movements of the carriage L, and thereby causing the rocking lever n to rock upon its axis and impart to the deliverer N a range of motion greater than the range of motion of the carriage L.
7. The gage-plate O, presenting its edge 0" in a position in which it intersects the path of motion of the rocking lever n, and means for horizontally adjusting the gage-plate 0,
R. O. Howns, M. L. ADAMS.