Improvements in Engraving Machines for Relief Work.
Year: 1891

page_text: Date of Application, 21st Oct., 1891-Accepted, 5th Dec., 1891
COMPLETE SPECIFICATION.
Improvements in Engraving Machines for Relief Work.
I, PAUL OTTO, of 102 Bergmann Strasse, Berlin, Germany, Engineer, 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:--
The boring of stamps, matrices, moulds, seals and such like engraving has,
hitherto, been done by means of engraving-machines, which effect the production
of the said articles by means of the pantograph. Under my invention the drawing
is transferred and suitably reduced from a pattern given to the piece to be worked.
In the engraving machines hitherto used, the borer-bit is adjusted for a certain
depth, in which position it remains till the boring of the figure is finished, so that
the point of the bit has only to polish the bottom-surface. But by this method
negatives only are obtained i.e., the engraved pieces can only be used to transfer
their pattern to other pieces by stamping, casting or coining, and are therefore
simply tools or moulds.
To obtain positives or relief-engravings, is the object of the present invention.
The principal difference between my machine and the old one is, that in the new
machine, the horizontal and vertical boring of the pattern, takes place at the same
time, whilst, in the old machine, only the horizontal boring was effected.
The improved machine is shown on the annexed drawings, whereon :-
Fig. 1 is a front view of the machine.
Fig. 2 a plan view.
Fig. 3 a view from the left-hand side.
Fig. 4 a view from the right-hand side.
On the bed A, which, according to requirement, might be fixed to a frame or to a
table, are:-
1st. The standard B, having a guide, in which works the two armed slide or
carrier C. The spindle D with the borer E is fitted in this slide, and is or may be
revolved by bands or cords on the pulley D'.
2nd. The slide rest F, on which the pieces to be bored are fixed.
3rd. The support G, with pantograph H, which is connected at one end with
rest F by means of bolt f, and bears on its other end only the small carrier J. In
this carrier and in the arm of the pantograph, is fitted the copying-bit K, which is
rounded off at the top and is, at the lower end, of a conic shape. It is arranged so
as to be easily raised and lowered, without shaking.
4th. The disc L, which is intended for the reception of the patterns to be copied.
This disc has dove-tailed parts, which enable it to be slid in a guide on the bed
plate A.
5th. The pillar M, which carries, on centring screws, the levers N and N'. The
levers hold in their forks, at the left hand, a vertical bar, with plate Q attached,
and in their right hand forks, the bar R with counter-weight S, which is intended
to counter-balance the weight of plate Q. The devices, as herein before described
in this paragraph, are for the purpose of preventing the plate Q and bar O
from being thrown off the truly vertical position, when being raised or lowered, no
matter what part of the plate Q is touched.
There is also screwed to standard B, the rail T, carrying a slide U, which,
according to convenience, can be slid to the right or to the left. On slide U, is,
movably, carried in centre, a lever V, which is connected at u, by a forked link y
with the slide C. Lever V bears, likewise, at the right hand, an adjustable
centre W. The weight S¹ is to counter-balance lever V and slide C; it is connected
by a cord VI to the and of the lowo

page_text: Before the manipulation of the borer is described, the following must be known,
that :-
1. The point of borer E must have exactly the same angle as the conical part of
the copying-bit K.
2. The patterns must always be worked in such a way that only the sides of the
copying-bit touch the edges of the pattern. The point of the conical part must
not push against it, as otherwise the copy becomes inaccurate.
3. The centre W must always lie firmly on the small piece of hardened steel P,
which is fixed on bar O and serves as a seat for the centre, and, likewise, the
plate must lie firmly on the upper rounded end of the copying-bit. As the
fever V with slide C and bar O with plate Q are counter-balanced, the safe
adjustment of the above named parts, relatively with each other, is effected by the
spiral-spring C, which normally presses the slide C down to the necessary lowest
position, as adjusted by screw.
The boring is done in the following manner :- -The piece to be bored is fixed on
slide rest F and the pattern on disc L and both put in the proper position towards
each other. If now the point of cone K leans against the even surface of the
pattern, the borer E must not, yet, touch the piece to be bored. There must still
remain a very small distance between the cone and the piece to be bored. This is
necessary, so that, if the borer should slip, the bored piece might not be spoiled, as
the borer does not touch the metal before the cone of the copying-bit is lowered
into the cut of the pattern.
If, now, the cone. is led along, in the pattern, it will be raised or lowered;
according as the outlines of the pattern get narrower or wider, in consequence of
which plate Q is raised or lowered, it being adjusted exactly parallel with table L,
together with the lever V and by means of arm Y the slide C with borer E. To
obtain now, by reduction with the pantograph H, the same depth as given by the
figure of the pattern, it is necessary that both reductions harmonize to a nicety
with each other. This harmony is effected by slide U, which may be adjusted
according to the adjustment of the pantograph.
On the drawing the reduction is t. If slide U is moved to the right, the bored
figures become smaller. If it is moved to the left, they become larger.
To transfer points or rectangular corners it is necessary to draw the cone towards
the point or corner, in consequence of which, it will be raised. As the point of the
borer has exactly the same angle as the cone, the very same patterns will be bored
as are described on the original. The borer may be adjusted deep or shallow.
Having now particularly described and ascertained the nature of my said inen-
tion and in what manner the same is to be performed, I declare that what I
claim is :-
H
1. A relief engraving machine, in which the copying-bit K, hereinbefore
described, moves, at the same time, the slide rest F, bearing the piece to be
worked, by means of a pantograph H, and a plate Qwhich by a lever-arrange-
ment NOW V U effects the adjustment with regard to height of a borer E, so
that the figure to be produced may be worked by borer E, at the same time, in a
horizontal and vertical direction, substantially as hereinbefore set forth with reference
to the drawings annexed.
Did this 20th day of Octahan 1801
H. D. FITZPATRICK.
70, Wellington Street, Glasgow, Agent.