Improvements in or relating to a Process for Forming Reliefs, Moulds and the like.
Year: 1897

page_text: Date of Application, 30th June, 1897
Complete Specification Left, 12th Mar., 1898--Accepted, 4th June, 1898
PROVISIONAL SPECIFICATION. .
Improvements in or relating to a Process for Forming Reliefs,
Moulds and the like.
I, JOSEF RIEDER, of Villa Leib, Munich-Thalkirchen, in the Empire of Germany,
Electrician, do hereby declare the nature of this invention to be as follows:-
This invention has for its object a process for forming reliefs and similar moulds
of metal by the electrolytic process, and consists mainly of the following arrange-
ment.
The mould, relief or the like which is to be formed is arranged on one side of
a porous block of gypsum, burnt clay, natural stone or the like. This takes place
by casting, for instance in the case of gypsum, English cement and other like
material, by impressing and subsequent burning in the case of clay, or by engrav-
ing in the case of natural porous stone.
A block of any of the above mentioned materials is placed on a plate of suitable
metal which is connected with the negative pole of a source of current.
The piece
of metal which is to be provided with the respective relief or design is placed on
the picture side of the block and is connected with the positive pole of the already
mentioned source of electric current. If the porous block be saturated with an
electrolyte suited to the metal of the relief plate, an electrolytic apparatus is
thereby formed in which the block represents the ordinary vessel filled with the
electrolyte, whilst the upper plate forms the anode and the lower one the cathode.
If the circuit be closed the metal is dissolved on the upper plate in the ordinary
manner, and always on those points which come in contact with the porous block.
By the automatic subsidence of the upper metal piece all the parts of its surface
which rests on the block come finally in contact with the latter, when the process
is finished.
In large pieces this system is not applicable and in that case the block is pressed
on the plates by means of a suitable spring device.
The process is applicable for making steel impressing stamps for stamping
coins and for forming coins and medals, for forming ornaments in the shape of
reliefs on pieces of metal of all kinds, for making blocks for printing purposes,
for boring holes in hard steel and the like.
As simple as the arrangement appears from the description, the practical
carrying out is not so simple. In addition to careful selection of the electrolyte,
there come into use in actual practice subsidiary apparatuses and means of assis-
tance which however do not alter anything in the system.
In an arrangement such as is employed for forming coins, the three main parts
only differ from the previously described arrangements in their shape. The
block is placed in a protective holder and the connection of the block and the
bottom plate or cathode is effected by means of the electrolyte contained in a suit-
able vessel. A cover on the latter carries the block and a mould is attached there-
to in which the anode or upper plate exactly fits so that this piece of metal
after being withdrawn can be replaced exactly in the same place.

page_text: The frequent withdrawal and cleaning is necessary for the purpose of obtaining
exact copies. The closing of the circuit is effected by means of suitable contacts.
Dated this 29th day of June 1897.
.. WM. P. THOMPSON & Co.,
Of 6, Lord Street, Liverpool, Agents for the Applicant.
Improvements in or relating to a Process for Forming Reliefs,
Moulds and the like.
I, JOSEF RIEDER, of Villa Leib, Munich-Thalkirchen, in the Empire of Germany,
Electrician, 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 has for its object a process for forming reliefs and similar moulds
of metal by the electrolytic process and consists mainly of the following arrange-
ment.
The mould relief or the like which is to be produced is first formed as a negative
on one side of a porous block of gypsum, burnt clay, natural stone or the like.
This may take place for instance in the case of gypsum, English cement and other
like material by casting, and in the case of clay by impressing and subsequently
burning, or in the case of natural porous stone by engraving.
A block or negative of this kind is shown diagrammatically in Figure 1 of
the accompanying drawings, whilst,.
Figure 2 shows a diagram of the arrangement for larger blocks;
Figure 3 shows the arrangement employed for forming the impressions.
The block E of any of the above mentioned materials is placed on a plate K
(Figure 1) of suitable metal which is connected with the negative pole of a source
of current. The piece of metal A which is to be provided with the respective
relief or design is placed on the picture side of the block E and is connected with
the positive pole of the already mentioned source of electric current. If the
porous block E be saturated with an electrolyte suited to the metal A of the relief
plate, an electrolytic apparatus is thereby formed in which the block E represents
the ordinary vessel filled with the electrolyte, whilst the upper plate A forms the
anode and the lower one K the cathode. If the circuit be closed the metal of the
upper plate or anode A is dissolved in the ordinary manner and always on those
points which come in contact with the porous block E. By the automatic sub-
sidence of the upper metal piece A all the parts of its surface which rests on the
block E come finally in contact with the latter, when the process is finished.
In large pieces this system is not applicable and in that case the block E is
pressed on the plate A by means of a suitable spring device f shown in Figure 2.
The process is applicable for making steel impressing stamps for stamping
coins and for forming coins and medals, for forming ornaments in the shape of
reliefs on pieces of metal of all kinds, for making blocks for printing purposes,
for boring holes in hard steel and the like.
An arrangement such as is employed for forming coins will be described, refer-
ence being had to Figure 3. The three main parts A E K only differ from the
previously described arrangements (shown in Figures 1 and 2) in their shape.
The block E is placed in a protective holder c and the connection of the block E
and the bottom plate K or cathode is effected by means of the electrolyte contained
in a suitable vessel g. A cover d on the latter carries the block E and a holder

page_text: or guide pieces h are attached thereto in which the anode or upper plate A exactly
fits so that this piece of metal after being withdrawn can be replaced exactly in
the same place.
The frequent withdrawal and cleaning is necessary for the purpose of obtaining
exact copies. The closing of the circuit is effected by means of suitable con-
tacts n and b.
Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed, I declare that what I
claim is:-
1. A process for forming reliefs and similar moulds of metal by the electrolytic
process consisting in casting or cutting in a block of porous substance such as
gypsum, earthenware or the like a negative of the article to be formed treating
as an anode the metal to be formed and pressing it with gentle pressure on the
negative face of the block, saturating said block with a suitable electrolyte and
connecting it with a cathode, substantially as hereinbefore set forth.
2. An apparatus for carrying out the herein described process which consists
of a porous block formed as a negative of the mould or article which is to be pro-
duced, which block rests with gentle pressure with its ornamental or negative
face against the anode to be operated on, and is saturated with an electrolyte, the
block being enclosed in a protective casing and the position of the anode secured
by means of a holder or guide pieces, substantially as hereinbefore described.
Dated this 11th day of March 1898.
WM. P. THOMPSON & Co.,
Of 6, Lord Street, Liverpool, Agents for the Applicant.