Improved Manufacture of Wedding Rings and Similar Plain Hoop Rings.
Year: 1898

page_text: Date of Application, 24th Feb., 1898
Complete Specification Left, 10th Nov., 1898-Accepted, 17th Dec., 1898
PROVISIONAL SPECIFICATION.
Improved Manufacture of Wedding Rings and Similar Plain Hoop
Rings.
I, WILHELM SCHWAHN, of No. 3, Hahnengasse, Hanau a/in, Germany, Goldsmith,
do hereby declare the nature of this invention to be as follows:-
Wedding rings are at present manufactured almost exclusively of 14 carat pale
gold; such gold is most suitable for the purpose, in particular on account of its hard-
ness, but it offers certain difficulties in its manufacture into rings.
Hitherto such rings have been manufactured by drawing gold wire through
suitable dies until it has about the lens-shaped cross section which wedding rings
always have. The wire is then cut in lengths corresponding to the desired diameter
of the ring, and the two ends are united by soldering, usually with a gold solder of
12 carats, but also frequently with a more fusible solder of less value. The soldered
joints frequently open and are never so smooth as not to require subsequent filing;
but under all circumstances it is required that no light coloured line of soldering
should be visible. The rings of the better kind thus produced are afterwards
finished in a lathe.
My present invention relates to an improved mode of manufacture which has the
advantage that all soldering, and all waste through filing and turning is avoided by
the manufacture of rings without soldered joints.
I will describe the method of manufacture with reference to the accompanying
drawing which shews the several stages thereof.
In the first place, annular discs are stamped out of a gold plate, and these are
then subject to a preliminary stamping in a die so that the one surface receives a
rounded configuration, as shewn at Fig. 1.
The annular disc thus formed is then introduced into a conical matrix so that
the rounded side lies inwards. A conical die C Fig. 2 is then introduced and is
pressed slowly downwards, so that, the disc is made to assume the form shewn in
Fig. 3. The ring thus obtained is then taken out of the matrix, and after inverting
it, it is introduced into the matrix again with its larger diameter directed down-
wards, as at Fig. 4.
The conical die is then again inserted and pressed downwards, whereby the ring
is made to assume the form shewn at Fig. 5.
After repeated turning over of the ring so that the larger diameter lies against the
narrower part of the matrix the die is again introduced as at Fig. 6 and is forced
downwards so as to expand the smaller side of the ring until this is of the
same diameter as the larger side, whereby the finished ring as at Fig. 7 is
produced.
By these gradual and successive operations, the ring receives, in addition to the
outer rounded form, also an internal rounded or swelled form with the greatest
projection at the middle which, as is well known, facilitates the putting on and
taking off of the ring.
Under the above operations, the internal diameter of the ring is gradually
increased while the outer diameter is gradually diminished, that is to say, by the

page_text: pressing process the outer periphery of the disc is gradually forced inwards, while
the inner periphery is expanded outwards.
In the same way, and by means of the same matrix the finished ring can also be
reduced in diameter, by employing a flat die instead of a conical one. By the
pressure of the flat die, the ring will be contracted on its lower side, and if
afterwards the ring is turned over, and again subjected to the pressure of the flat die
the other side will also be contracted.
The rings thus produced are so round and smooth that they require no subsequent
working beyond polishing.
DOLL
Wahuan 1000
COMPLETE SPECIFICATION.
Improved Manufacture of Wedding Rings and Similar Plain Hoop
Rings.
I, WILHELM SCHWAHN, of No. 3, Hahnengasse, Hanau a/m, Germany, Goldsmith,
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 :-
Wedding rings are at present manufactured almost exclusively of 14 carat pale
gold; such gold is most suitable for the purpose, in particular on account of its
hardness, but it offers certain difficulties in its manufacture into rings.
Hitherto such rings have been manufactured by drawing gold wire through suitable
dies until it has about the lens-shaped cross section which wedding rings always have.
The wire is then cut in lengths corresponding to the desired diameter of the ring,
and the two ends are united by soldering, usually with a gold solder of 12 carats,
but also frequently with a more fusible solder of less value.
The soldered joints frequently open and are never so smooth as not to require
subsequent filing; but under all circumstances it is required that no light coloured
line of soldering should be visible. The rings of the better kind thus produced are
afterwards finished in a lathe.
My present invention relates to an improved mode of manufacture which has
the advantage that all soldering, and all waste through filing and turning is avoided
by the manufacture of rings without soldered joints.
I will describe the method of manufacture with reference to the drawings
accompanying my Provisional Specification which shews the several stages thereof.
In the first place, annular discs are stamped out of a gold plate, and these
are then subject to a preliminary stamping in a die so that the one surface receives
a rounded configuration as shewn at Fig. 1. The annular disc thus formed is then
introduced into a conical matrix so that the rounded side lies inwards. A conical
die C Fig. 2 is then introduced and is pressed slowly downwards so that, the disc is
made to assume the form shewn in Fig. 3. The ring thus obtained is then taken out
of the matrix, and after inverting it, it is introduced into the matrix again with its
larger diameter directed downwards, as at Fig. 4.
The conical die is then again inserted and pressed downwards, whereby the ring is
made to assume the form shewn at Fig. 5.
After repeated turning over of the ring so that the larger diameter lies against the
narrower part of the matrix the die is again introduced as at Fig. 6 and is forced down-
wards so as to expand the smaller side of the ring until this of the same diameter
as the larger side, whereby the finished ring as at Fig, 7 is produced.

page_text: By these gradual and successive operations, the ring receives, in addition to the
outer rounded form, also an internal rounded or swelled form with the greatest pro-
jection at the middle which, as is well known, facilitates the putting on and taking off
of the ring.
Under the above operations, the internal diameter of the ring is gradually increased
while the outer diameter is gradually diminished, that is to say, by the pressing
process the outer periphery of the disc is gradually forced inwards, while the inner
periphery is expanded outwards.
By the
In the same way and by means of the same matrix the finished ring can also be
reduced in diameter, by employing a flat die instead of a conical one.
pressure of the flat die, the ring will be contracted on its lower side, and if after-
wards the ring is turned over, and again subjected to the pressure of the flat die the
other side will also be contracted.
The rings thus produced are so round and smooth that they require no subsequent
working beyond polishing.
Having now particularly described and ascertained the nature of this invention
and in what manner the same is to be performed, I declare that what I
claim is
Manufacture of weddings rings and similar plain hoop rings by first stamping an
annular blank out of a gold plate then pressing the same in a die so as to impart
a rounded configuration to the cross section, and then subjecting the ring to a
succession of pressing operations by means of a conical matrix and die between each
of which operations its position is inverted, whereby it is first brought into a conical
shape and then into a cylindrical form with a lens-like cross section, substantially as
described.