Screw Cutting or Milling Die Stocks.
Year: 1889

page_text: Date of Application, 29th Aug., 1889-Accepted, 16th Nov., 1889
COMPLETE SPECIFICATION.
Screw Cutting or Milling Die Stocks.
We, JAMES HERVEY STERNBERGH Iron Manufacturer, residing at 530 North Fourth
Street and ROBERT PEMBERTON Engineer, residing at 727 North Second Street, both
in the City of Reading, Berks County Pennsylvania United States of America, do
hereby declare the nature of our invention for, SCREW CUTTING DIE-STOCKS, 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 Screw Cutting Die-Stocks and more especially
to that class in which the cutters are adjustable simultaneously for the purpose of
varying the diameter of the threaded bolts or of releasing them from the finished
work. It is adapted for cutters having a longitudinally grooved face which is hold
tangent to the work.
Heretofore screw cutting die-stocks have been used in which the cutters have been
simultaneously adjusted radially. Our invention is adapted to give the cutters a
simultaneously pivotal movement in a novel and effective manner and it consists in
the arrangement of the cutters and mechanism for moving them as fully set forth
herein.
Fig. 1-Is a full top view of our screw cutting die-stock showing two cutters in open
position and the other two removed.
Fig. 2 Is an irregular section of the die-stock and the cutter holder mainly on the
line X Y Z of Fig. 1.
Figs. 3 and 4 show modifications of our invention.
A represents the die-stock or plate provided with sockets A³ for suitable handles.
The cutter holders B are pivoted to the stocks A by moans of Trunnions B¹ which
pass through holes A³ in the stocks, and cutters C provided with a longitudinally
grooved face are held at a proper incline for the angle of the thread in suitable slots
in the holders by means of clamps D and nuts, after having been adjusted by screws E.
Pins B2 project from the under face of the holder and enter eccentric slots G¹ in the
upper face of an annular plate G which is recessed into the stock A so that its upper
surface is level with the upper surface of the stock. A guide thimble F is secured in
the centre of the latter and its extension F¹ reaches nearly to the cutters, which move
over it.
The mechanism employed to turn the plate G which engages with and operates the
cutters, consists of a vertical shaft H journalled in the heavy part of the stock and
provided with an arm H¹ which extends towards the centre of the stock A a sufficient
distance for its end to enter a recess G in the under surface of the plate. A lever J
is secured to the projecting end of the shaft H for the purpose of turning the latter
and extends beyond the end of the socket A² to which a quadrant K is secured. This
quadrant is provided with a scale and suitable means for holding the lever in any
desired position as determined by the diameter of the thread to be cut.
Our die-stock is intended more particularly for use in a hand tool but is also adapted
to be chucked in a lathe or bolted, as through holes Aº to a face plate or the table of
a drill press, and to be thus used for screw cutting or milling purposes. The operation in
any case is substantially the same. The cutters are set so as to do an equal amount
of work on any size of bolt and are then simultaneously and equally opened or closed
to any desired extent by moving the lever J to the proper position on the quadrant K.
The guide thimble F may be changed to suit the size of the bolt to be worked on.
The eccentric Slots G₁ are entirely covered by the holders and the chips can in no way
interfere with the proper working of the parts. The cutters are arranged with the
grooved face tangent to the work, are moved directly and accurately to and from said
) work, and being provided with ample clearance and adapted to cut with the greatest

page_text: keeness instead of pushing and bruising the metal, superior work is accomplished with
greatly reduced labor and wear.
We do not limit our invention to the exact construction shown as the latter may be
considerably modified without departing from the spirit of our invention. Fig. 3, for
instance shows a modification in which the plate G is provided with pins Leach of
which is in engagement with the surfaces B³ and B of two adjacent pivoted cutter
holders in such a manner that the movement of the plate G in the direction indicated
by the arrow will move the cutters simultaneously towards the centre, and a corre-
sponding movement in the opposite direction will in like manner withdraw them. The
mechanism for rotating the plate for the purpose of adjusting the cutters consists of a
worm M gearing with a toothed portion of the periphery of the disc and rotated by
means of a wheel N secured to the opposite end of the worm shaft.
This wheel may be graduated on the face and set to a line on the socket A² for
exact adjustment; the worm will securely hold the plate to any point to which it is
set. Fig. 4, is a similar section to that shown in Fig. 2 of a die-stock in which the
plate is rotated by means of a bevel pinion P on the end of a shaft R passing through
one of the handles of the tool and terminating in a suitable wheel S which may bear
against a graduated face A7. These and other modifications and equivalents involving
the principle of our invention it is intended shall be included as a part of it.
Having now particularly described and ascertained the nature of our inven-
tion and in what manner the same is to be performed, we declare that what we
claim is :-
(1)-The combination with a die-stock and cutters pivotally secured to the front face
of said stock, of a sliding plate located within a recess in said front face and engaging
each of said cutters, and means for sliding the plate substantially as set forth.
(2) In a screw cutting die-stock the combination with the cutter holders pivoted
to the front face of the die-stock, of a plate located within a recess in the front face of
the die-stock and provided with eccentric slots each of which engages a pin projecting
rearwardly from the holders, and means for sliding said plate all substantially as set
forth.
(3) The combination with a die-stock having a recess in the front face thereof,
and a movable plate within said recess, of cutters pivotally secured to the front face
of the die-stock and engaging a movable plate, and a rotary shaft for actuating said
plate, substantially as set forth.
(4) The combination with a die-stock, movably secured cutters, a sliding plate
engaging each of said cutters, and means for sliding said plate, of the removable guide
thimble passing through the plate substantially as set forth.
(5) In a screw cutting die-stock the combination of the movable cutter holders,
the recessed plate engaging the holders, the removable guide thimble, and means for
sliding said plate, all arranged and adapted to operate substantially as set forth.
Deted
1001
T
BOY WY LAYAH
JAMES HERVEY STERNBERGH.
ROBERT PEMBERTON.
Abel & Imray,
Agents for the Applicants.
JAMES HERVEY STERNBERGH.
ROBERT PEMBERTON.
Abel & Imray,
Agents for the Applicants.