Improvements in and connected with the Manufacture of Punches.
Year: 1899

page_text: Date of Application, 11th July, 1899-Accepted, 18th Nov., 1899
COMPLETE SPECIFICATION.
Improvements in and connected with the Manufacture of Punches.
I, ANDREW JACKSON BRADLEY, Salesman, of St. Louis, in the State of Missouri,
United States of America, 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:-
My invention relates to the manufacture of punches. Its principal object is to
facilitate the process of forging a punch from a hot blank and it consists in a
finishing die the sides of whose design are formed parallel to the axis thereof.
It also consists in a punch forging machine provided with a forming die and a
finishing die having the same design formed with its sides parallel to the same
axis and means for causing said finishing die to continue or complete the result
produced by the forming die. It also consists in the parts and in the combination
of parts hereinafter described and claimed.
In the accompanying drawing, which forms part of this specification,
Figure 1 is a horizontal section of a press provided with my invention, the
section being taken on the line 1-1 of Figure 2.
Figure 2 is a central vertical section of the press on the line 2-2 of Figure 1.
Figure 3 is a front view showing the machine in elevation, the view being taken
on the plane 3, 3, Figure 1 behind the hand wheel of the chuck.
Figure 3A is a rear view of my machine on a smaller scale.
Figure 4 is a face view and Figure 5 is a cross section on the line 5, 5, Figure 4
of the first forming die, showing a draft.
Figure 6 is a face view and Figure 7 is a cross section on the line 7, 7, Figure 6
of the second forming die, showing the sides parallel.
Figures 8 and 9 are side views of the blank after being operated on by the first
and the second die, respectively.
Figures 10 and 11 are perspective views of the blank and the finished punch
respectively.
My invention may be utilized in divers kinds of presses but I find a drop-press
1 suitable therefor. The ram or hammer 2 of the press is provided with a device
or devices 3 adapted to hold forming dies 4, a convenient form of such device
being dovetail grooves in the under face of the said ram. The two forming dies
are engraved or otherwise formed with approximately the same design, one of said
dies having the design cut slightly larger in contour than is desired for the
finished article and being formed with a draft or bevel, and the other die being
formed with the edges of the projecting design portion parallel and with the
design made of the same size as the finished article. The forming dies being
mounted on the same ram or hammer remain at a fixed distance apart; in fact,
it is desirable to have the two dies cut in the same plate in order to render their
relative positions permanent.
On the bed 5 is a chuck 6, 7 arranged to slide in suitable guides 8 such, for
instance, as the dovetail grooves shown in the drawing. The chuck consists of
a heavy block 6 arranged to slide in the grooves 8, and a second block 7 fitting
into a chamber made therefor in the first block G and arranged to slide in grooves 9

page_text: ju said first block 6. The upper surfaces of said blocks are flush and their meeting
faces have steel bushings fitted thereto which constitute the real jaws of the
chuck and are made of a shape suited for the blank to be operated upon. These
steel jaws 10 preferably project above the blocks 6, 7 in order the better to protect
said blocks from the impact of the hammer.
A screw-threaded collar 11 is secured to the main block 6 of the chuck by sup-
porting bars 12 extending laterally therefrom; and through this collar works a
threaded shaft 13. The outer end of this shaft has a hand-wheel 14 thereon and
the inner end has a nut or ring 15 fastened thereon to turn therewith. This ring fits
in a space provided therefor between the face of the block 7, and a piece 16
mounted on said block 7, so that 'the block 7 is moved to and fro on the block 6
according as the shaft 13 is turned one way or the other. The effect of this move-
ment is of course to open or close the chuck, although as the block 7 and the
shaft are both mounted on the block 6, said block 6 remains stationary during such
operation.
For the same reason the movement of the block 6 carries with it all parts of the
chuck without altering their relative positions. Such movement may be con-
veniently effected by a hand lever 17 pivotally fastened to a lug 18 projecting
from the middle portion of said block, and pivotally fulcrumed to a link 19
pivotally secured to the frame of the press. Obviously, other means for shifting
the chuck may be used in place of that described.
The sliding block 6 is limited in its to and fro movement by adjustable stops 20.
Evidently these stops may be located on the frame of the press in the path of the
block; but it is preferable to mount them upon the block itself. As shown in the
drawing, these stops may consist of set screws 20 working in threaded hangers 21
depending from said block 6. Nuts 22 will set them in any position to which
they may be adjusted.
The operation of the device is as follows:-The forming dies 4 are first mounted
on the drop hammer or ram in as nearly perfect alignment as is practicable and
parallel with the line of travel of the chuck, so that the impression made by one
of the said dies upon a blank held in the chuck can be centred under the other die
by merely shifting the chuck. While the chuck is centred beneath each die,
successively, the adjustable stops 20 are turned until they strike the frame of the
press, and are thereby set to limit the movement of the chuck in both directions,
so that in either of its extreme positions thus ascertained the chuck is accurately
centred beneath one or other of the two forming dies.
The blank 24 to be operated on is then placed, while heated preferably to a light
cherry heat, between the open jaws of the chuck. Then the hand wheel 14 is
turned to move the block 7 against the block 6 thus clamping the blank between
the steel bushings. The blank shown in the drawings is an ordinary bolt without
a thread and is particularly applicable for the making of stencil character punches
for stencil machines. The shank fits between the steel jaws and its head rests on
the circular steel bushing in suitable position to receive the impact of the hammer."
The hand-lever 17 is then shifted until the stop 20 strikes the frame of the press
in which position the hot bolt is directly under the first forming "die, the die
shown in Figure 4. The hammer then falls causing the first die to impress its
design pyramidally in said blank, which is left as shown in Figure 8. 'The
hammer is then raised, the hand lever is shifted as far as the stop will permit,
(which is directly under the finishing die) and the hammer is again dropped,
thereby displacing the pyramidal side portions back far enough to make all the
longitudinal edges of the projecting portion parallel and thus completing the
formation of the face portion of the punch, which may be ejected from the press
by any suitable contrivance. As the object sought to be attained is parallelism
of the sides of the design portion of the finished punch, it is obvious that the
finishing die may be formed with a slight relief or clearance which is the reverse
of the draft or taper of a forming die and the practical equivalent of parallel
sides.

page_text: Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed, declare that what
I claim is:
1. A finishing die for forming stencil character punches, having the sides of its
design formed parallel, substantially as described."
2. A machine for forming stencil character punches, comprising a finishing die
mounted on the hammer and having the sides of its design formed parallel,
substantially as described.
3. A machine for forming stencil character punches, comprising a hammer
having a forming die and a finishing die of the same design, said finishing die
having the sides of its design parallel, and means for centering the work relatively
to each die successively, substantially as described.
4. A machine for making punches comprising the combination of two forming
dies mounted on the hammer, one of said dies having its design formed with a
draft and the other having the same design formed with parallel sides, a chuck
movably secured to the bed of the press and limiting devices for centering said
chuck beneath each of said dies, substantially as and for the purpose set forth.
5. The process for manufacturing punches, which consists first in impressing
upon the blank, by means of a taper die, a design in relief with tapering sides,
and thereafter by means of another die bearing a similar design but without
draft or taper removing the taper from the sides of the relief design formed by
the first die, substantially as set forth.
Dated this 11th day of July 1899.
For the Applicant,
J. G. LORRAIN, M.I.E.E., M.I.Mech. E.,
Norfolk House, Norfolk Street, London, W.C., Chartered Patent Agent.