Improvements in Electro-plating.
Year: 1893

page_text: Date of Application, 20th May, 1893
Complete Specification Left, 81st Oct., 1893-Accepted, 2nd Dec., 1893
PROVISIONAL SPECIFICATION.
[Communicated from abroad by HERMANN THOFEHRN, of 11, Rue Bosio, Paris,
France, Engineer.]
Improvements in Electro-plating.
I, ERNEST DE PASS, of 78, Fleet Street, in the City of London, Fellow of the
Chartered Institute of Patent Agents, do hereby declare the nature of this inven-
tion to be as follows:-
This invention relates to a process and apparatus whereby electrolytic depositions
of copper, or other metal, can be obtained in such a manner that the deposit
possesses great thinness and perfect homogeneity.
According to this invention, and in order to obtain a smooth deposit of copper,
or other metal, upon a cylinder, or a moulded or shaped article, rotating in an
electrolytic bath, or upon an article placed in the bath, such as a plate, the surfaces
to be plated are showered with a stream or jets, under pressure, of the electrolyte,
which acts either continuously or intermittently during the whole of the electrolytic
operation, and said showering may be effected by means of perforated or slotted
tubes or discharge pipes which may advantageously receive a reciprocating motion.
To prevent the electrolyte becoming disturbed during the action of the current or
jets directed onto the cathodes, the anodes are placed at a suitable distance from
the bottom of the tank. The electrolyte is drawn off from the bottom of the tank
and delivered into a purifying reservoir, or reservoirs, wherein it is cleansed of
impurities and afterwards restored to its standard strength, and is then again
showered on to the cathodes, a constant circulation of the electrolyte being thus
kept up.
The anodes may be arranged upright, or at an inclination, upon a conductor
which is suitably insulated so as to be unattackable by the electrolyte. In the case
of articles which require to be rotated, the cathodes may be mounted on a revolving
axis so that all portions of the articles to be plated can be subjected to the action
of the current or jets directed upon them, but when the articles do not require to be
rotated they may be supported in a suitable frame.
The electric current is led to the anodes, which are coupled up in quantity, and
passes thence through the electrolytic liquid to the cathodes, which are also
coupled up in quantity, whence it passes to the next bath, and so on, back to its
starting point.
Dated this 20th day of May 1893.
ERNEST DE PASS.
COMPLETE SPECIFICATION.
Improvements in Electro-plating.
1, ERNEST DE PASS, of 78, Fleet Street, in the City of London, Fellow of the
Chartered Institute of Patent Agents, do hereby declare the nature of this inven-
tion and in what manner the same is to be performed, to be particularly described
and ascertained in and by the following statement, reference being had to the
accompanying drawings and to the letters and figures marked thereon, that is
to say :-
This invention relates to a process and apparatus whereby electrolytic depositions
of copper, or other metal, can be obtained in such a manner that the metal
deposited has great fineness and perfect homogeneity.
According to this invention, and in order to obtain a smooth deposit of copper,

page_text: or other metal, upon a cylinder, or a moulded or shaped article, rotating in an
electrolytic bath, or upon an article such as a plate placed in the bath, I shower
onto the surfaces to be plated, a stream or jets of the electrolyte, under pressure,
and either continuously or intermittently during the electrolytic operation. To
prevent the electrolyte becoming disturbed during the action of the current or jets
that are directed onto the cathodes, the anodes are placed at a sufficient distance
from the bottom of the tank so as to avoid the inconvenience above mentioned.
The electrolyte is drawn off from the bottom of the tank, and delivered into a
purifying reservoir, wherein it is cleansed of impurities, and afterwards restored to
its standard strength, and it is then again showered onto the cathodes, a constant
circulation of the electrolyte being thus kept up.
The anodes are placed either upright, or at an inclination, upon a conductor
which is protected, except at the points of contact with the anodes, by an insulating
layer of indiarubber, guttapercha, or the like, covered with lead.
In the case of articles requiring to be rotated, so as to ensure their being properly
covered with the deposit all over, and to subject all portions of the deposit to the
action of the jets of liquid directed against them, I mount the cathodes on an axis;
but in the case of articles not requiring rotation, in order to be in complete contact
with the liquid jets, I retain them in position by placing them upon a frame, or
transverse rails.
The electric current, coming from any source, is led to the anodes, which are
coupled up in quantity, and passes thence through the liquid to the cathodes, also
coupled up in quantity, whence it passes to the next bath, and finally returns to its
starting point.
And in order that the invention may be readily understood in all its details, I
will describe the same with reference to the annexed drawings, in which the same
numerals indicate similar parts.
Fig. 1 represents a general section of the installation of an electrolytic bath
according to the improvements which constitute the invention.
Fig. 2 is a transverse section of the tank in which the deposition is effected.
Figs. 3 and 4 are two sections, taken at right angles to each other, of a tank for
the deposition of metals on flat surfaces.
The working is as follows;-It being assumed that cylinders or tube mandrels
are to be plated with an electrolytic metal (see Figs. and 2); and indeed it
would be the same if it were required to plate. any revolving surface. The
cylinders are mounted on gudgeons 2, and are rotated through suitable gearing,
such as straps 4, 5, actuated from a shaft 3 driven by any motor. The electric
current enters at 6, goes to the anodes which are arranged in an upright or inclined
manner at 7, near the bottom of the tank, and all coupled up in quantity, traverses
the bath, deposits the metal upon the cathodes 1, and leaves at 8 to return to its
source. The electrolyte is kept in constant circulation by a pump 9 which draws
off the liquid. from the tank and forces it into a reservoir 10, placed at a higher
level, wherein the liquid is purified, that is to say, freed from matters which are
injurious to the quality of the deposit. From the reservoir 10, the liquid passes
into a neighbouring reservoir 11, wherein it is restored to its standard strength,
and from which it is showered upon the cathodes, under a pressure regulatable
according to the elevation of the feed tank 11. The showering takes place through
suitably shaped discharge pipes 12, which may receive a reciprocating movement
longitudinally, so that all parts of the cathode will be equally showered upon.
the case of cylinders, these discharge pipes are straight, but in the case of
revolving surfaces they may conform to such surfaces. These discharge pipes 12
are perforated with small holes, arranged very close together, so that all parts of
the metallic deposit will be acted upon by the liquid jets falling under a pressure
which may be easily regulated. A longitudinal slot, extending all along the
discharge pipe, would answer the purpose equally well.
In
When it is desired to produce the showering, under a very feeble pressure, a
simple overflow may be substituted for the discharge pipe.

page_text: Owing to the combination of these means, I obtain a perfectly homogeneous
metallic deposit on the surface of the cathodes, giving to the metal the qualities
required by the trade.
In the arrangement indicated by Figs. 3 and 4, where it is desired to obtain '
deposits upon flat surfaces, the cathodes 1 are inclined so as to receive the jets
from the discharge pipes 12, which jets, entering under pressure as in the previous
arrangement, wipe or finish off the deposit as formed.
The revolving cathodes 1, may be arranged vertically instead of horizontally, as
shown in Figs. 1 and 2.
When the metal to be eliminated from the electrolyte is an easily oxidizable one,
the cathodes may be placed near the bottom of the bath in the saturated liquid,
and the anodes above them in the impoverished electrolyte, and this may be done
without in any wise altering the invention; the cathodes will then be showered
upon at their lower part.
Having now particularly described and ascertained the nature of this inven-
tion and in what manner the same is to be performed, I declare that what I
claim is :-
1. In electrolytic operations for depositing a metal on cathodes of any form, the
continuous or intermittent showering of the said cathodes with fresh liquid, under
pressure, from discharge pipes, in the manner herein explained.
2. In electrolytic operations for depositing a metal upon rounded cathodes such
as cylinders, tube mandrels, revolving surfaces, etc., the combination of the system
of showering under pressure (forming the subject of the previous claim) with the
rotation of the cathode around a horizontal or vertical axis, substantially as
described.
3. In electrolytic operations for depositing a metal upon cathodes of any form,
the combination of the system of showering under pressure previously described,
and of the arrangement of anodes (coupled up in quantity) in a position remote
from the liquid jets, so that the bath is not disturbed, substantially as described.
4. In electrolytic operations for depositing a metal upon cathodes, the com-
bination of the horizontal or vertical rotary movement of the cathodes with a
circulation of liquid, so directed as to shower upon the cathodes jets of fresh liquid
under pressure in a continuous or intermittent manner, and with an arrangement of
anodes coupled up in quantity and remote from the liquid jets, substantially as
herein described.
Dated this 21st day of October 1893.