IMPROVEMENTS IN ELECTRIC GENERATORS
Year: 1883

page_text: LETTERS PATENT to John Ambrose Fleming of 3 Greenhill Villas, Hampstead
in the County of Middlesex, Doctor of Science for an Invention of
"IMPROVEMENTS IN ELECTRIC GENERATORS "
PROVISIONAL SPECIFICATION left by the said John Ambrose Fleming at
the Office of the Commissioners of Patents on the 5th February 1883.
JOHN AMBROSE FLEMING of 3 Greenhill Villas Hampstead in the County of
Middlesex Doctor of Science "IMPROVEMENTS IN ELECTRIC GENERATORS
My Invention relates to the formation of primary galvanic Batteries whereby
greater constancy of current can be obtained and the internal resistance reduced,
and it has reference to the formation of a primary galvanic battery in which the
positive electrode consists of a Carbon block of coarsely cellular structure, or a cage
or cages formed of carbon rods or a cage or cages formed of sheets of carbon pierced
with apertures filled with small carbon blocks, an oxidizing liquid being supplied
to the interior of this structure cage or cages by a pipe or pipes so as to rapidly
depolarize the carbon and to obtain a highly permeable carbon electrode without
the use of a porous plate or septum of any kind of non-conducting material.
In carrying out my Invention I construct the positive electrode of small rods of
graphite cut out of the solid Gas Carbon or moulded out of compressed finely
powdered Carbon. These rods are fixed on to a base board of insulite ebonite or
any convenient material or even one made of carbon, and so arranged as to form a
species of rectangular cage of vertical rods the space between the rods being about
equal to a quarter of the diameter of the rods and the cage being open at the top.
The Carbon rods are all connected together metallically by putting a small collar
on the top of each of brass or copper and soldering these collars together. In this
way the Carbons are in electrical connection. The interior of this Cage is then
filled with short cylinders of graphite or pieces built up like bricks with spaces
between up to say about 2 inches below the top of the cage. A lead pipe pierced
with small holes is then laid on the top of the cage. One or more such electrodes
are built up and provided for each cell. These electrodes are placed in a rectangular
[Price B21

page_text: cell of non conducting material and separated from each other by distance pieces of
non conducting material; between these is placed the zinc or negative plate The
positive electrodes are connected by a metallic strip. The battery is by preference
excited by a mixture of sulphuric acid sal ammoniac and Bichromate of Potash or
I may use other exciting fluids. A stream of strong solution of Bichromate of
Potash is allowed to trickle out through the lead pipe placed in the Carbon cage
and filters down through the Carbon blocks. In place of forming a Cage of rods
I may form a Cage of Carbon by moulding graphite powdered into the form of a
box, piercing it full of holes and filling the interior with Carbon blocks,--or I may
mould or otherwise shape graphite or other form of Carbon into a block of coarsely
cellular structure

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said John Ambrose Fleming in the Great Seal Patent Office on the
1st August 1883.
JOHN AMBROSE FLEMING of 3 Greenhill Villas Hampstead in the County of
Middlesex Doctor of Science "IMPROVEMENTS IN ELECTRIC GENERATORS "
My said Invention of Improvements in Electric Generators relates to the
formation of primary galvanic batteries whereby greater constancy of current is
obtained and the internal resistance is reduced.
In carrying out my said Invention the positive electrode of the battery is formed
of a skeleton, or open work, frame, cage or cages of carbon filled with or containing
small blocks or pieces of carbon, an oxidizing liquid being supplied to the interior
of this frame, cage, or cages so as to rapidly depolarize the carbon, and to obtain a
highly permeable carbon electrode without the use of a porous plate or septum of
non-conducting material between the positive electrode and the negative
electrode.
And in order that the said Invention may be perfectly understood I shall now
proceed more particularly to describe the same and for that purpose shall refer to
the several figures on the accompanying sheet of drawings which illustrate the best
method with which I am at present acquainted of carrying the said Invention into
effect the same letters of reference indicating corresponding parts in all the
Figures.
Figure 1 of the accompanying drawings represents a longitudinal section of a
galvanic battery constructed according to my said Invention, Figure 2 is a transverse
section and Figure 3 a sectional plan of the same.
A is the positive electrode which is constructed of small rods a of graphite cut
out of the solid gas carbon, or moulded out of compressed finely powdered carbon
These rods are fixed a small distance apart from each other into a base board b of
insulite, ebonite or any other suitable material or even one made of carbon and are
so arranged as to form a skeleton frame or a species of cage open at the top. The
carbon rods a are all connected together metallically by placing a small collar c
say for example of brass, copper, or lead on the top of each and connecting these
collars together by a wire d soldered thereto, so that the collars are in electrical
connection The interior of this cage is then filled to say about two inches below
the top with broken pieces e of graphite, or with cylinders or small pieces of carbon
in other forms, which pieces may be built up after the manner of bricks with
intervening spaces Two or more of such positive electrodes are provided for each
cell, two, marked A, A, being shown in the example illustrated, and they aro
connected together, and to a metallic strip f for forming a connection with con-
tiguous cells. These electrodes are placed in a rectangular cell B of non-conducting
material and separated from each other by distance pieces g, of nonconducting
material and between them is placed the zinc or other negative plate C.
The battery is by preference excited by a mixture of sulphuric acid, salammoniac,
and bichromate of potash or I may use other exciting fluids. A stream of strong
solution of bichromate of potash or other oxidizing liquid is supplied by a lead or
other pipe or pipes pierced with small holes, placed either over or within each cage.
These pipes are not shown in the drawings but they may be arranged in any
convenient manner so as to allow the liquid to trickle out and filter down through
or between the pieces of carbon.
It is obvious that the cage may be constructed in a variety of forms as for
example, circular, with the zinc or negative plate forming a tube around it, and the
pipe for the supply of oxidizing liquid extending down vertically at the centre of

page_text: the cage, but as any such modifications will readily suggest themselves to those
skilled in the arts it is not thought necessary to illustrate them:
I may also form an openwork frame, or cage of carbon by moulding powdered
graphite into the form of a box and piercing it full of holes, or building up the
same of grooved strips, the interior of the frame or cage being filled with sinall
picces or blocks of carbon as before.
Having now described and particularly ascertained the nature of my said
Invention of Improvements in Electric Generators and the manner in which the
same is or may be used or carried into effect I would observe in conclusion that
what I consider to be novel and original and therefore claim as the invention of
improvements in Electric Generators to be secured to me by the herein before in
part recited Letters Patent is :-
A primary galvanic battery, the positive electrode of which is formed of a skeleton
or openwork frame, cage or cages, of carbon filled with, or containing blocks or
pieces of carbon, an oxidizing liquid being supplied to the interior of this frame,
cage, or cages all substantially as hereinbefore described.
In witness whereof I the said John Ambrose Fleming have hereunto set my
hand and seal this twenty fourth day of July in the year of Our Lord One
thousand eight hundred and eighty three.
TALEN
JOHN
זin
AALUR
FL
TUURLINGT 1.S.)