Year: 1887

page_text: Date of Application, 28th Dec., 1887
Specification Accepted, 2nd Mar., 1888
I, CHARLES DAKE ROGERS of Providence County of Providence State of Rhode
Island, U.S.A. Mechanic do hereby declare the nature of this invention and in what
manner the same is to be performed, to be particularly described and ascertained in
and by the following statement :-
This invention relates particularly to certain improvements in machines for forming
the screw-threads on screw-blanks by means of the "rolling process" so called, and
consists, essentially, of a blank-holding guide adjustably mounted between the adjacent
working faces of the thread-forming dies, all as will be more fully hereinafter set forth
and claimed.
""
The object of my present invention is to provide means for holding screw-blanks in
a vertical position while the latter are being acted upon by the thread-forming dies.
The screws thus held or guided and produced, being superior to "rolled-thread
screws as heretofore made by machines unprovided with means for vertically retaining
the blank in position.
It is practically found in threading the screws that a great number of them are
rendered inferior or worthless, owing to the fact that the attendant, or the mechanical
"feeder" when used, fails to properly enter the blanks between the dies.
In the three accompaning sheets of drawings, Figure 1 represents a side elevation
of a machine adapted to form screw-threads on screw-blanks and provided with my
blank-holding device. Fig. 2 is an enlarged transverse sectional view, taken on
line x-x of Fig. 6. Fig. 3 is a detached view of the rear guide-plate. Fig. 4 is a
similar view of the front guide-plate. Fig. 5 is a view of the upper plate, adapted to.
serve as a gauge for limiting the upward movement of the blank. Each of the said
plates being provided with means for adjusting its position with reference to the screw-
blank. Fig. 6, sheet 2, is an enlarged side view of a portion of the machine, showing
the screw-blank retained by the guide in its normal position. Fig. 7 is a similar view,
showing the rear die advancing, and the guide with its blank, also travelling ahead.
The blank at the same time, having the screw-thread rolled therein. Fig. 8, sheet 3,
represents a side view of the travelling dies, one above the other, with a blank (in
section) lying horizontally between them. Fig. 9 is a transverse sectional view

page_text: showing a means for centralizing and retaining a blank in position while being acted
upon by two travelling dies to form a screw-thread thereon. Fig. 10 is a reduced side
view showing travelling dies adapted to roll a V-shaped groove into the peripheral
surface of a rod. Fig. 11 is a transverse vertical sectional view, showing a rod retained
in position laterally while being submitted to the action of two travelling dies. The
latter adapted to roll or impress a V-shaped groove into the rod. Fig. 12 is a partial
sectional view, showing a screw-blank vertically retained in position. The device
permitting the blank to readily turn on its axis, but at the same time, preventing
lateral movement while being acted upon by the two moving dies. Fig. 13 is a front
elevation of the device represented in Figs. 6 and 7. The difference being that the
guides are adjustably-secured to a stationary part of the machine in lieu of the carrier,
and both dies are adapted 'to travel, and Fig. 14, is a similar view of the stationary
device, with the steadying lever and dog for operating the same removed.
In all the drawings, it will be observed that the blank or rod is retained in position,
or centralized, in such manner that it is at the same time adapted to turn freely on its
axis. In case the guide be dispensed with, the blanks then very frequently inter-
mittently slip or slide along between the faces of the dies, thereby, in the making of
screws producing thin and otherwise imperfect threads.
The immediately following description relates to a machine adapted to form a screw-
thread upon blanks by means of impressing dies.
A, designates the improved machine as a whole. a. indicate the bed or frame
and the supporting legs, respectively. s, indicates the driving-shaft mounted in
bearing secured to the top of of said bed.
is a stationary guide, secured to
the bed.
D, as drawn, indicates one of the thread-forming dies. The same being secured to
the front side of the bed or frame. D' indicates the suitably mounted travelling die,
its grooved face (m²) forming the counterpart of the adjacent face of the stationary
die D. The die is further provided at its rear end, with a short vertical arm (Fig. 1)
to which is jointed the connecting-rod c, which in turn is jointed to the disk or
crank d, secured to the driving shaft s. By means of this arrangement a rectilinear
reciprocating movement is imparted to the die. The "stroke" being about twice the
length of the stationary die D.
The following refers especially to the guiding device for the blanks, which forms the
subject of the present invention.
O, designates a carrier, constructed to slide freely in an endwise direction, in the
stationary guide g. The rear end of the carrier is jointed to a connecting-rod c. A
pin mounted in the revolving crank-disk d', and passing through the rear end of said
rod c¹, serving to impart a reciprocating motion to the carrier. The stroko being just
one-half that of the die D' before described.
H, indicates the rear guido plate, made of thin steel, the same being adjustably
secured to the front face of the carrier by means of screws, k, passing through the
elongated screw-holes u.
The front end of said plate is extended, as at t, and terminating in the vertical.
edge e. Immediately below said extension, the plate is cut away, at e, and having
the edge es, thereof made at an angle with the lower edge of the plate. A hub, 2, is
formed in the upper forward portion of the plate, all as clearly shown in Fig. 3.
H¹, (Fig. 4) designates the forward steel guide-plate. The same having an elongated
opening h, thereby adapting the plate to be adjustably secured to the carrier. The
rear edge of the lower half of this plate consists of the two vertical faces e¹, e,
terminating in the notched portion e. The offset edge, e, in conjunction with that of
the plate, H, bears against opposite sides of the plain or unthreaded portion of the
shank of the screw. The lateral extension (e) being equal to the height of the
screw-thread.
To the face of the plate, H', is adjustably secured the vertical guage-plate, H³,.
having its lower end bent rearwardly, as at r, thereby forming a vertical stop to the
screw..
L, designates a two-arm or" bell-crank "lever; the same-being pivoted in front to

page_text: the hub, ; of the plate H, by means of the pin l. The lower or vertical arm of said
lever is bent rearwardly, at P, thereby causing its lower portion to travel in the vertical
plane with the steel plates H¹, H. The thickness of the arm being substantially the
same as that of said plates. The forward edge, 2, of the arm, l, is slightly beveled,
so that its lower end is in line with the forward edge, e, of the plate II, as clearly
indicated in Fig. 6. The rear edge of the arm is also beveled, and adapted to engage
the angularly cut edge e³, of the plate. The upper arm, of the lever L, extends in
advance of the arm 12, and is provided at its free end with the enlargement m. The
latter engaging the upper surface of a block, n, secured to the stationary die D.
The said surface consisting of the level portion n', and the cam-shaped or beveled
portion n.
In the machine illustrated herewith, the adjacent working faces of the dies D, D',
are of the same length. The former die being stationary, while the latter travels at a
rate of speed which is twice that of the forward movement of the screw-blank upon
its axis, or, in other words, the natural movement of the blank. (when embraced
between the two dies) is exactly one-half that of the travelling die. Therefore, the
speed of the carrier, C, is made the same as that of the screw-blank.
The operation is as follows :-
Assuming first, however, that the machine is provided with suitable driving mechanism
for actuating the movable die D¹, and the carrier C.
Now, the several parts being in the normal position represented in Fig. 6, (the two
crank pins being at the same time on the "dead center") a blank 6 is then placed
between the edges, e, of the front and rear plates H₁ H, which have been previously
adjusted to the size of the wire forming the blank. The head, p, extending up into
the space e, while the point, p², of the blank rests upon the top surface, s³, of
the bed.
It will be observed that the arm, , of the pivoted lever L, rests upon the horizontal
surface n', of the stationary block n, thereby bringing the lower forward end of the
other arm, l, against the blank. Now, in revolving the shafts, motion is imparted to
the said carrier and die D¹. The former with its attached plates and lever, thereby
being forced ahead which causes the blank to traverse the distance, t, and engage the
stationary die at the same instant that the rear, or movable die-having first traveled
the distance t plus t¹-engages the opposite side of the blank. The continuous rotation
of the shaft next causes the dies to form the gradually enlarging screw-thread on the
blank's shank. The boss m of the lever L, meanwhile, in advancing, follows the
surface of the block n. The inclined portion, n', thereof being so proportioned or
formed that the edge, e², of the lower arm gradually assumes a perpendicular, as the
screw-thread is formed, thereby positively retaining the blank or screw in a vertical
position during the thread-forming operation. It will be seen that the slight rearward
pressure of the screw is borne by the said edge e, in conjunction with the opposed
contact of the boss m, sliding along the block n. As the carrier, die, etc. further
advance, the thrust of the screw is transmitted to the rear edge of the arm 1, then
bearing against the inclined surface e³, of the rear steel plate, H.
The final forward movement of the said travelling parts carries the then finished
screw beyond the front end of the stationary die, after which the screw may be
automatically, or otherwise, removed from the guide.
The back stroke now returns the die D₁, etc., to the normal position, to receive
another blank, b, as before described. See Fig. 6.
By means of the screws, k, the steel guide plates may be adjusted so as to receive
other sizes of blanks.
Obviously the thread-forming dies are to be adjustably mounted.
It is evident that the dies may be so arranged as to receive the blanks in a horizontal
position, as shown in Figs. 8 and 9. In these, and the succeeding Figures both of the
dies are represented as travelling. The blanks being stationary, with reference to the
forward movement of the dies, although freely revolving upon their axes. In Fig. 11,
ears, pt, extend up from the base a which are transversely drilled to receive a rod b.
The latter having a V-shaped groove g¹ rolled or impressed therein by means of the

page_text: gradually increasing raised
dies D. See also Fig. 10.
step a, while the
stationary base or frame, p,
contact with the blank.
V-shaped portion of the oppositely mounted and driven
In Fig. 12, the screw-blank, b, rests upon an adjustable
is centered by a cone-shaped hood, ds, mounted in a
A spring serving to maintain the guide or hood in close
By simply securing the guide plates, H, H¹, to a stationary arm or vertical
extension, w, formed on the bed a and then moving the dies D, D' toward each other,
as shown in Fig. 13, the action of the lever L, upon the block, n and blank, is
substantially the same as herein before described with reference to Figs. 6 and 7,
wherein the die D, is stationary and the guide-plates are secured to a carrier C.
It is apparent now that a blank-screw, or rod, may, by means of my invention, be
placed between the working faces of a pair of suitably mounted and operated dies,
and positively retained in the same relative position during the entire stroke or move-
ment of the die, or dies. The device in no wise preventing the work at the same time
from freely turning on its axis.
Heretofore, in order to effect this result, even approximately, the working faces of
the dies have been roughened. But this is found to be ineffectual. Such roughening,
moreover, is necessarily impressed into the surface of the screw or rod, thereby
producing screws, etc., of an inferior quality. Even with the use of such roughened
dies, unless the attendant be very careful to place the work at exactly right angles
with the face of the dies the finished product will be inferior or wholly unfit for use.
By means of thus improperly placing the blank, the dies, in working, are frequently
broken or rendered unserviceable.
Having now particularly described and ascertained the nature of my said inven-
tion, and in what manner the same is to be performed, I declare that what I
claim is :-
1. The combination, with suitably mounted and operated forming-dies, one of which
may be stationary, of a combined blank-holder and guide consisting of a fixed plate
and a pivoted lever portion mounted on a carrier, whereby a blank is maintained in
position parallel to the adjacent faces of the dies, substantially as specified.
2. The combination, with two suitably mounted thread-forming dies, and mechanism
for operating the same, of adjustably mounted guide plates and a pivoted lever adapted
to co-act with said plates, by means of which a screw-blank or rod is maintained
parallel to and between the working faces of the said dies, substantially as hereinbefore
described.
3. In a machine of the class hereinbefore referred to, the combination, with two
oppositely mounted and operated thread-forming dies, of adjustably mounted plates,
as H, H, and H2, a pivoted lever, as L, and a carrier to which said plates are secured,
arranged and adapted to maintain a blank in position parallel to and between the
working faces of said dies, substantially as shown and specified.
4. In a machine for rolling or impressing screw-threads into a blank, the
combination, with the suitably mounted and operating threading dies of a screw-blank
guide mounted to travel between said threading-dies, and mechanism for operating the
blank guide, substantially as described and for the purpose set forth.
5. The combination, with the thread-forming dies, mounted to impress a screw-
thread into a screw-blank, of the blank guide hereinbefore described, provided with
means for adjusting the same to different sizes of blanks, and mechanisms for imparting
a reciprocating movement to said guide, substantially as shown and for the purpose
specified.
6. In a screw-threading machine, of the class hereinbefore described and shown,
the combination, with the stationary thread-forming die D, the oppositely mounted
travelling thread-forming die D¹, and means for reciprocating the same, of a carrier C,
means for reciprocating the carrier, and the blank guide adjustably secured to said
carrier, substantially as and for the purpose set forth.
7. The combination, with the stationary thread-forming die D having an irregular
or cam-shaped upper surface, as n¹, n', of the guided carrier C, means for reciprocating

page_text: the carrier, and the screw-blank guide consisting of plates H, H¹, H², and pivoted
lever L, adjustably secured to the carrier, substantially as shown and hereinbefore set
forth.
8. The combination, with the suitably mounted thread-forming dies, D D¹, a
block, n, secured to the die D, and the guided reciprocating carrier C, of the notched
front and rear plates, H¹, H, adjustably secured to said carrier, an adjustably secured
plate, H2, adapted to limit the upward movement of the blank, and the pivoted two-
arm lever, L, adapted to simultaneously engage the block n and the screw-blank, all
constructed, arranged, and operating, substantially as shown and for the purpose
hereinbefore set forth.
9. The combination, with the movable thread-forming die D¹, the stationary die D,
having an attached block n and the carrier C, having the screw-blank holding
plates H H H2, adjustably secured thereto, of the two-arm lever L, pivoted to the
carrier, having its front arm 1, engaging the block n at the same time that its other
arm engages the lower portion of the screw-blank.
10. The plates H¹, H, each having the adjacent edges or ends, e, adapted to receive
a screw-blank and means for adjustably securing the blanks to a carrier, substantially
as shown and set forth.
11. The combination, with the adjustably mounted plates H¹, H adapted to receive
a screw-blank between their adjacent ends, said plate H, further having its front lower
corner cut away, as at es, of the pivoted two-arm lever L, having the lower portion of
its vertical arm adapted to rest against the edge e³, of the plate H, prior to the
completion of the screw-thread.
TL
AFL
NT
1007