IMPROVEMENTS IN APPARATUS CHIEFLY DESIGNED FOR THE ELECTRO DEPOSITION OF METALS AND THE PRODUCTION OF LIGHT BY ELECTRICITY
Year: 1878

page_text: LETTERS PATENT to Geminiano Zanni, of Highbury, in the County of..
Middlesex, Medical Electrician, for the Invention of "IMPROVEMENTS IN
APPARATUS CHIEFLY DESIGNED FOR THE ELECTRO DEPOSITION OF METALS
AND THE PRODUCTION OF LIGHT BY ELECTRICITY."
Sealed the 6th May 1879, and dated the 11th November 1878.
PROVISIONAL SPECIFICATION left by the said Geminiano Zanni at the
Office of the Commissioners of Patents on the 11th November 1878.
":
GEMINIANO ZANNI, of Highbury, in the County of Middlesex, Medical Elec-
trician. "IMPROVEMENTS IN APPARATUS CHIEFLY DESIGNED FOR THE ELECTRO
DEPOSITION OF METALS AND THE PRODUCTION OF LIGHT BY ELECTRICITY."
My Invention relates to improved apparatus chiefly designed for generating and
regulating electrical currents for the deposition of metals and for lighting.
My said Invention comprises various improvements in dynamo-electric machines
that may be used for all purposes for which such machines are now employed, and
I provide apparatus specially applicable for the electro deposition of metals whereby
I am enabled to regulate with great case and simplicity the strength or depositing
power of the current in the bath, according to the number or size of the articles to
be coated or covered, thus ensuring an equally good effect under varying circum-
stances, this result being very difficult to obtain with the machines and appliances
heretofore used.
In carrying into practice my improvements in dynamo-electric machines I con-
struct the machine with a series of stationary electro-magnets, each one of which
is composed of a soft iron bar or core surrounded by wire coils and placed within a
metal frame, preferably made of case-hardened steel. The said soft iron bars or cores
are hollow, to provide for the passage of a current of cold water through them in
order to keep them cool. The electro-magnets thus formed are attached to the
interior circumference of the case of the machine, being arranged in circular order.

page_text: .
The rotary coil of the machine is composed of a soft iron ring made in separate seg-
ments, and around each of these segments I wind a quantity of insulated copper
wire. The ring is attached to the shaft of the machine and revolves within the
circle formed by the aforesaid stationary magnets. The segments of the ring are
formed with tongues and grooves, so that they may be readily attached to or detached
from each other. The advantage gained by so constructing the ring is that the
coiling of the wire around the same is more readily effected than with a continuous
ring, and the wire may be coiled more tightly and uniformly.
In order to provide means for regulating the strength of the current in the bath
when using a dynamo-electric machine for electro-deposition I provide a regulating
or so called resistance apparatus which is constructed as follows, that is to say :-
Around a bar of ebonite or other suitable non-conducting material I coil naked or
uncovered German silver wire, and the coil thus formed is so arranged and placed in
the circuit that by operating a key or lever provided for the purpose and in con-
nection with the said coil, I can cause the current to take a longer or shorter path
through the resistance of the German silver wire, and the strength of the current in
the bath is thereby rendered greater or less, accordingly I effect this object by con-
'necting each coil of the wire around the bar of non-conducting material to a point or
stud placed in a convenient position for the aforesaid key or lever to be brought in
contact therewith as desired. The said key or lever is so connected in the electrical
circuit that the current passes through it and through that part of the coil with
which it may be in connection, thus making the circuit longer or shorter. As a
convenient manner of operating I may fix the points or studs and the key or lever
upon a board or plate, the whole to be placed in a convenient position upon the
dynamo-electric machine, so that the workman or attendant may readily shift the
key as required according to what strength of current is wanted in the bath at any
particular time.
In connection with this arrangement I provide a galvanometer, which is placed in
the circuit and indicates at all times the number of revolutions the machine is making.
It is desirable that the machine should be kept at the same speed, otherwise the
placing of the key or lever on any one point or stud would not ensure the same
strength of current in the bath. As the galvanometer indicates the speed the
attendant is able to regulate the same should it fall below or exceed that which it is
desirable to maintain.
I desire it to be understood that the above described devices for regulating the
current in the bath, also the galvanometer, may be applied to any existing dynamo-
electric machines as well as to a machine provided with the improvements first herein
set forth.
When using a dynamo-electric machine constructed according to my said Inven-
tion for the purposes of electric lighting I do not employ the said regulating devices,
as they are not then required, but I retain the galvanometer to indicate the speed
of the machine.
My said Invention also comprises an apparatus for developing the electric light
generated by machines, as herein described or otherwise, and is constructed as
follows, that is to say-I provide two cylindrical rods of carbon which are provided
at each end with toothed wheels. These rods are placed parallel to each other and
in such a position that the toothed wheels at each end of one rod engage with the
corresponding toothed wheels at each end of the other rod, so that if one rod rotates
the other must also rotate. One of these rods is capable of adjustment nearer to or
farther from the other, and the toothed wheels on this rod are formed cone-shaped,
or they may be said to be a series of toothed wheels diminishing in diameter for the
purpose of allowing this rod to be moved nearer to or farther from the other rod
and still be in engagement therewith. The said rods are placed in the electrical
circuit and are adjusted relatively to each other so that the electric arc is produced
between their surfaces at a part near one end of the said rods when commencing to
operate. The rods are made to revolve by means of a weight or spring as the
'carbon wears away, and when one complete revolution has been made no more light
"

page_text: is emitted at that part of the circumference of the rods, but continues to be emitted
from that part of their circumference next to the part which has first been consumed,
and so the light continues to be emitted until a sufficient number of revolutions has
been made to cause the whole of the surface to be worn away to a certain depth,
whereupon a magnet provided for the purpose comes into action and brings the
adjustable rod towards the other one, so that their surfaces will again be at the
proper distance from each other for developing the light which will continue to be
emitted while the rods continue to revolve, as above described. When the surfaces.
are again worn away for a certain depth, as before, the magnet again comes into
operation and the adjustable rod is again brought sufficiently near to the other rod.
This continues until the carbons are entirely consumed, and provision is thus made
for a long continuance of the light without supplying fresh carbons.
I may vary the arrangements and devices for rotating and otherwise operating the
rods without departing from the spirit of the said Invention.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Geminiano Zanni in the Great Seal Patent Office on the 10th May
1879.
GEMINIANO ZANNI, of Highbury, in the County of Middlesex, Medical
Electrician. "IMPROVEMENTS IN APPARATUS CHIEFLY DESIGNED FOR THE ELECTRO
DEPOSITION OF METALS AND THE PRODUCTION OF LIGHT BY ELECTRICITY."
My Invention relates to improved apparatus chiefly designed for generating and
regulating electrical currents for the deposition of metals and the production of
light.
My said Invention comprises various improvements in dynamo-electric machines
that may be used for all purposes for which such machines are now employed, and
I provide apparatus specially applicable for the electro-deposition of metals whereby
I am enabled to regulate with great ease and simplicity the strength or depositing
power of the current in the bath, according to the number or size of the articles to
be coated or covered, thus ensuring an equally good effect under varying circum-
stances, a result very difficult to obtain with the machines and appliances heretofore
used.
Figure 1 is an end elevation shewing my improved construction of the rotary coil
of a magneto-electric machine, and also the stationary electro-magnets in connection
with the same, and,
Figure 2 is a side view of one of the said stationary magnets shewing the method
of coiling the wire upon the same.
Figure 3 is a side elevation of my improved apparatus for regulating the strength
of the electric current, as hereinafter described.
Like letters indicate the same parts throughout the Drawing.
In carrying into practice my improvements in dynamo-electric machines I con-
struct the machine with a series of stationary electro-magnets a, each one of which
is composed of a soft iron bar or core a¹ surrounded by wire a* coiled in the
direction indicated in Figure 2 and placed within a metal frame b, preferably formed
of soft iron. The said soft iron bars or cores a¹ are made hollow to provide for the
passage of a current of cold water through them to keep them cool, the water being
admitted to the said cores by means of pipes e connected with any suitable source of
supply. The electro-magnets thus 'formed are attached to the interior circumference
of the case of the machine and are arranged in a circle, as shewn in Figure 1. The
rotary coil of the machine is composed of a soft iron ring d made in separate seg-
ments d¹, and around each of these segments I coil a quantity of insulated copper
wire d*. The said ring d is attached to the shaft e of the machine and revolves
within the circle formed by the aforesaid stationary magnets a. Each segment d¹
of the said ring is formed with a tongue d² and a groove d³, and the said segments
may thereby be readily attached to or detached from each other. The advantage
gained by constructing the ring d in separate parts or segments is that the coiling
of the wire around the ring may be more readily effected and the wire may be
coiled more tightly and uniformly on the same than upon a continuous endless ring
as heretofore employed.
In order to provide means for regulating the strength of the current in the bath
when using a dynamo-electric machine for the electro-deposition of any metal, I
employ a regulating or resistance apparatus, as shown in Figure 3 of the Drawing,
and which is constructed as follows, that is to say:-Around a cylinder or bar fof
ebonite or other suitable nonconducting material supported in suitable bearings g, g',
I coil naked or uncovered wire, preferably German silver wire f*. The coil thus
formed is so arranged and placed in the circuit that by operating the handle h on

page_text: shaft of the said bar or coil I can adjust a device, which I term a key, and thereby
cause the current to take a longer or shorter path through the resistance of the
German silver wire, the strength of the current in the bath being thereby diminished
or increased as desired. I effect this object by connecting one end of the coil of
wire to one pole of the dynamo-electric machine, and the wire from the other
pole of the said machine is connected to the post g in which one end of a shaft i
carrying a small grooved wheel or pulley * is supported. The said wheel, which
constitutes the key, is free to rotate and slide upon the shaft i, and is arranged
in contact with the wire coil; by turning the crank or handle h on the shaft fin
either direction the cylinder f is caused to rotate, and by its rotation the coil of
wire f* in contact or gearing with the key wheel * will cause the same to be
moved end wise upon its shaft, thereby causing the current to take a longer or shorter
path through the aforesaid German silver wire f*, or I may modify this resistance
apparatus by employing a key lever arranged to come in contact with a point or
stud connected to the coil of wire f* upon the cylinder f, and so connected in the
electrical circuit that the current passes through it and through that part of the
coil with which it may be in connection; by adjusting this lever the circuit may be
made longer or shorter, as desired. I may fix the regulating apparatus above
described upon a frame or plate, the whole to be placed in a convenient position
upon the stand of the dynamo-electric machine, so that the workman or attendant
may readily operate the aforesaid crank handle or key as required, according to the
strength of current required in the bath at any particular time.
In connection with the above described apparatus, and preferably placed upon
the stand or support of the same, I provide a galvanometer which is arranged in the
circuit and indicates at all times the number of revolutions the machine is making
and also the strength of the current. It is desirable that the machine should be
kept running at the same speed, otherwise the adjustment of the aforesaid crank
handle wheel or key to any particular position in connection with the coil of the
regulating apparatus above described would not at all times ensure the same
strength of current in the bath. As the galvanometer indicates the speed the
attendant is able to regulate the same should it fall below or exceed that which it
is desirable to maintain.
I wish it understood that the above described devices for regulating the current
in the bath, and also the galvanometer, may be applied to any existing dynamo-
electric machine, as well as to a machine provided with the improvements first
herein set forth.
When using a dynamo-electric machine constructed according to my said Inven-
tion for the purpose of electric lighting I do not employ the said regulating appa-
ratus, as the same is not then required, but I retain the galvanometer to indicate
the speed of the machine, as above described.
i
For developing the electric light generated by machines, as herein described or
otherwise, I employ an apparatus constructed as follows, that is to say I provide
two cylindrical rods of carbon which are furnished at each end with toothed wheels.
These rods are placed parallel to each other, and in such a position that the toothed
wheels at the end of one rod engage with the corresponding toothed wheels at the
ends of the other rod, so that if one rod rotates the other must also rotate with it.
One of these rods is capable of adjustment nearer to or farther from the other, and
the toothed wheels on this rod are cone-shaped, or they may be said to be a series of
toothed wheels diminishing in diameter for the purpose of allowing this rod to be
moved nearer to or farther from the other rod while remaining in engagement or gear
therewith. The said rods are placed in the electrical circuit, and are so adjusted
relatively to each other that the voltaic or electric arc is produced between their
surfaces at a part near one end of the said rods when commencing to operate. The
said rods are caused to revolve by means of a weight or spring as the carbon wears
away, and when one complete revolution has been made light is no longer emitted
at that part of the circumference of the rods, but continues to be emitted from that
part of their circumference next to the part which has first been consumed, the

page_text: light therefore continues to be emitted until a sufficient number of revolutions
has been made to wear the whole of the surface away to a certain depth, whereupon
a magnet, provided for this purpose, comes into action and moves the adjustable rod
towards the other rod, so that their surfaces will again be at the proper distance
from each other for developing the light, which will continue to be emitted while
the rods continue to revolve, as above described. When the surfaces are again worn
away for a certain depth, as before, the magnet again comes into operation and the
adjustable rod is again brought sufficiently near to the other rod. This operation
continues until the carbons are entirely consumed, and provision is thus made for a
long continuance of the light without supplying fresh carbons.
Having thus fully described my said Invention and the manner of performing
the same, I wish it understood that I claim,—
First. The improvements relating to the stationary magnets and rotating coil,
and consisting in the combination of the coil constructed in the peculiar manner
specified, and shewn in Figure 1, with the magnets which have the wire coiled
on them in the direction shewn in Figure 2, all as and for the purposes specified.
Second. The improved apparatus or device for regulating the current, as described
with reference to Figure 3 of the Drawing, and for the purposes specified.
Third. The combination with a dynamo-electric apparatus of the said regulating
or resistance apparatus, or a galvanometer, or both, upon a frame or stand, thereby
uniting these parts in such a manner as to form one compact and convenient machine,
as and for the purposes specified.
In witness whereof, I, the said Geminiano Zanni, have hereunto set my
hand and seal, this Tenth day of May, in the year of our Lord One
thousand eight hundred and seventy-nine.
GEMINIANO ZANNI. (L.S.)