IMPROVEMENTS IN ELECTRICAL APPARATUS
Year: 1876

page_text: [C
LETTERS PATENT to Cecil Wray and Leonard Wray, junior, both of Ramsgate,
in the County of Kent, Gentlemen, for the Invention of IMPROVEMENTS IN
ELECTRICAL APPARATUS."
Sealed the 13th June 1876, and dated the 6th March 1876.
PROVISIONAL SPECIFICATION left by the said Cecil Wray and Leonard
Wray at the Office of the Commissioners of Patents on the 6th March 1876.
CECIL WRAY and LEONARD WRAY, junior, both of Ramsgate, in the County of
Kent, Gentlemen. "IMPROVEMENTS IN ELECTRICAL APPARATUS."
This Invention relates to that class of electrical apparatus known as thermo-
electric piles or batteries, and in which the thermo-electric bars or metals are
arranged or bult up radially in series around a heating chamber. All electric piles
of this description now in use have certain defects, many of which are of so serious
a nature as to render the piles comparatively useless for all practical purposes.
To remedy these defects is the object of the present Invention, which consists
firstly in forming the heating chamber of a cylinder or casing of fireclay or other
suitable material, and of any convenient diameter, and which may be made in
sections if desired. A Bunsen or other burner is placed concentrically inside this
cylinder or casing so as to leave an annular space between the burner and the
cylinder or casing, to which space the external air may be admitted through a
regulator at the lower end of the cylinder or casing. In order to more equably
distribute the gas or inflammable vapour supplied to the burner, and also to prevent
the annoyance caused by the explosions which frequently occur in this class of
burner on lighting or turning off the gas or vapour, we employ a wire gauze
cylinder which we place concentrically inside the combustion chamber. The
thermo-electric bars or couples are arranged or built up radially around the heating
chamber, so that one end of each bar or couple shall be close to or abut against the
outside of the cylinder or casing. By constructing the apparatus in this manner,
the deleterious effects caused by the influence of the external air and the damp, and
also by the direct action of the flame of the gas or vapour on the inner ends of the
bars or couples, are avoided.
The next improvement relates to the mode of building up the series or layers of
I Price G1

page_text: thermo-electric bars, and consists in placing between each series or layer an annular
disc, plate, or frame of a non-conducting substance. These discs or plates are
provided on one side with three or more triangular or other shaped lumps or pro-
jections which are intended to support the weight of the discs, plates, or frames
carrying the bars above them. If desired the tiers of bars may be divided into or
built up in sections, and if more or less power be required for any particular purpose
a section or sections may be added to or taken from the apparatus as desired.
Thus a great saving will be effected in transport of the apparatus, and in the cost
of repairing the same should any of the parts become broken or useless. Binding
rods may be made to pass through the lumps or projections on the discs or plates
for the purpose of holding together the tiers of bars forming the sections of the
pile.
The next improvement relates to the form given to the end of the positive bars
or plates, our object being to obtain a good metallic connection with the negative
"bars" or plates, having a large surface with but small electrical resistance, and
without unduly weakening the ends of the negative bars or plates. The form
which we give to the ends of these bars or plates as answering best to the above
requirements, is that of a dovetail having one or more perforations therein according
to the size of the bar. The positive and negative bars or plates are connected
together in the usual manner during the casting of the latter. After the positive
bars are cut to the required form, and before the connection is made with the
negative bars, the former are coated with zinc, copper, or other suitable metal, for
the purpose of protecting and preventing the decomposition of the metal of which
they are composed.
If preferred, the apparatus may be heated by coke or other fuel instead of by gas,
for which purpose some of the parts will necessarily be somewhat modified in
construction.
We construct the heating chamber by preference of fire-clay or other refractory
substance either in one piece or in sections, and of any desired form or dimensions,
and around and against the outer sides of this furnace or fire chamber the therino-
electric bars or couples are arranged radially as in the former instance, so that they
may receive the heat given out by the refractory material while the fire is burning.
A distinctive feature of this fire chamber is a vertical opening, which is provided
with a door or doors for ascertaining from time to time the condition of the fire,
and to facilitate the removal of clinkers, and for stoking. purposes. The fire chamber
is provided with fire-bars, and also with a lid and chimney.
SPECIFICATION in pursuance of the conditions of the Letters Patent filed by the
said Cecil Wray and Leonard Wray.in the Great Seal Patent Office on the
6th September 1876.
CECIL WRAY and LEONARD WRAY, junior, both of Ramsgate, in the County of
Kent, Gentlemen, "IMPROVEMENTS IN ELECTRICAL APPARATUS."
This Invention of "Improvements in Electrical Apparatus" relates to that class of
electrical apparatus known as thermo-electric piles or batteries, and in which the
thermo-electric bars or couples are arranged or built up in horizontal series around a
heating chamber. All electric piles of this description hitherto constructed have
certain defects, some of which are of so serious a nature as to render the piles
comparatively useless for all practical purposes. To remedy these defects is the
object of the present Invention, and the mode in which we effect this is shewn
in the accompanying Drawing, in which Fig. 1 is a vertical section of a thermo-
electric pile constructed according to our Invention. Fig. 2 is a plan or top view
of the same, and Fig. 3 is a horizontal section of the pile taken in the line 1, 2, of
Fig. 1.

page_text: Our first improvement consists, firstly, in forming the heating chamber of a
cylinder or casing a, a, of fire-clay or other suitable material and of any convenient
diameter, and which may be made in sections if desired. A Bunsen or other burner
6 is placed concentrically inside this cylinder or casing so as to leave an annular
space between the burner and the cylinder or casing, to which space the external air
lieated or otherwise may be admitted through openings c, c, Fig. 1, at the lower end
of the cylinder or casing a. In order to regulate the admission of air to the annular
space inside the cylinder a, an adjustable plate d is fitted to the pipe e in such a
manner that it may be screwed up or down thereon, and in order to more equally
distribute the gas or inflammable vapour supplied to the burner, and also to prevent
the annoyance caused by the explosions which frequently occur in this class of
burner on lighting or turning off the gas or vapour, we employ a wire gauze cylinder
which we place concentrically inside the burner b, as shewn at Fig. 1. Instead of the
cylinder a and burner b shewn in Fig. 1, we sometimes employ a heating chamber
made of iron or other suitable metal, and consisting of a cylindrical or other shaped
double vessel (hollow in the centre) containing a heating medium or fluid, such as
oil, tallow, or an easily fusible metal, which on being heated by burning gas, or other
means, becomes sufficiently hot to heat the ends of the bars or couples up to the
desired point; but in this case, and whenever we use a metal to form the heating
chamber, we coat or cover the outside of the said metal tube or chamber with nica,
or other suitable non-conducting substance. The thermo-electric bars or couples
ffff, are arranged or built up radially or otherwise around the heating chamber
a, a, so that one end of each bar or couple f shall abut against and be in contact
with the outside of the cylinder or casing a; as shewn at Figures I and 3, when this
is made of a non-conducting material, but when it is made of metal, then the bars
ff, will abut against and be in contact with the mica, or other substance which
covers the metal tube or heating chamber. By constructing the apparatus in this
manner the injurious effects caused by the influence of the external air and the
damp, and also by the direct action of the flame of the gas or vapour on the inner
ends of the bars or couples, are avoided.
The next improvement relates to the mode of building up the horizontal series or
layers of thermo-electric bars f, f, and consists in placing between each series or
layer of bars an annular disc, plate, or frame g of a non-conducting substance. One
of these discs or plates g is shewn in plan at Fig. 4, and in section at Fig. 5. It
will be seen that each one of these discs or plates g is provided on one side with
triangular or other shaped blocks or projections g', g', g', of which there may be any
convenient number. These blocks g' are intended to support the weight of the
discs, plates, or frames g carrying the bars f above them. It will be evident that
the blocks or projections g', g', may if desired be made separate from the circular
dises or plates g, g, and may be built up thereon. If desired the tiers of bars f, f,
may be divided into or built up in sections, vertical or otherwise, containing any
convenient number of tiers or layers of bars. In Fig. 1 the pile is shewn as com-
posed of three sets of bars, and if more or less power be required for any particular
purpose, a section or sections may be added to or taken from the apparatus, so as to
increase or diminish the power of the pile as desired. Thus a great saving will be
effected in the transport of the apparatus and in the cost of repairing the same should
any of the parts become broken or useless. Binding rods h, h, are made to pass
through some of the blocks or projections g', g', on the discs or plates g for the purpose
of holding together the tiers of bars f, f, forming the sections of the pile. The pile of
bars thus made is placed on a foundation plate and is covered at top with another
plate. The two plates are then connected together by vertical tie or binding rods
,,, which will hold the several parts of the apparatus firmly together.
The next improvement relates to the form or forms given to the ends of the
positive bars or plates i, i, our object being to obtain a good metallic connection
with the negative bars or plates f, f. Moreover, by constructing the positive bars or
plates i, i, in the manner shewn and hereafter described, a large surface with but

page_text: small electrical resistance is obtained without unduly weakening the ends of the
negative bars or plates f, f. The form or forms which we give to the ends of these
bars or plates i, i, as answering best to the above requirements, will be better
understood by by referring to Figures 6 and 7, which represent longitudinal vertical
and horizontal sections of one of these compound bars drawn on an enlarged scale.
It will be seen that the form or forms which we give to the ends of these bars or
plates i, i, is that of a dovetail or dovetails having one or more perforations therein,
according to the size of the bars f, f, and to the dovetail or dovetails on the connecting
piece, intended to connect the outer or cool end of the negative bar f to the end of
the positive bar of the next pair, we provide an elongation or tongue i¹ of varying length
according to the length of the bar f, but in no case should the tongue be sufficiently
long to touch the dovetail at the heated end. After these positives i, i, are cut to
the desired form or forms they are coated (by electricity or otherwise) with any
suitable metal or metals, for the purpose of preventing the oxidation or decompo-
sition of the metal of which they are made, and also for obtaining a more perfect
metallic connection between the positive and negative bars, but we do not bind our-
selves always to employ this coating of the positive bars. The bars or plates may
be made of any of the thermo-electric series of metals, substances, or alloys, and may
also be constructed of any desired form or size.
The positive and negative bars or plates are connected together by casting the
latter on the former in suitable moulds; but in so doing we cast the bars funder
the pressure of a head of metal of varying height. This head of metal may vary
according to the size of the bars and the purpose for which they are to be used from
four inches to two feet in height. We would here remark that it should be clearly
understood that the terms "positive and negative" will naturally interchange or
vary according to the metals employed and their relative position (electrically) to
each other as is well known.
When the metals, substances, or alloys of which the bars are made are difficult to
unite properly with each other (such as antimony and bismuth) we cast the positivo
and negative bars in pairs on a piece of iron or other suitable metal, which will serve
to connect them and carry the current. This form of compound bar is shewn at
Fig. 8. The positive bar ix is made of a brittle positive metal (say bismuth) and
the negative bar f is made of a brittle negative metal (say antimony), and the two
are connected together as also the several pairs by means of the thin iron or other
metal plate i, i. made with dovetails and elongated tails i, i, which are cast into the
thick bars as shewn at Figures 6, 7 and 8.
In heating the pile of bars in these machines, coke or other fuel may be used
instead of gas, in which cases some of the parts will necessarily be modified in
construction to suit the fuel to be so employed. Fig. 11 is an external elevation of
an apparatus which is intended to be heated by means of coke or other solid fuel
which is capable of being burned in a suitable fire-place provided with fire-bars.
Fig. 12 is a horizontal section of the same.
When the thermo-electric pile is intended to be heated by coke, charcoal, coal or
other suitable fuel, we construct the heating chamber by preference of fire-clay or
other refractory material, either in one piece or in sections and of any desired
form or size. In the Drawing this chamber a, a, is of a cylindrical form. Should this
chamber be constructed of such a refractory material as iron or other metal, an in-
sulating material is interposed between it and the ends of the bars, that is to say,
the metal may be surrounded by an envelope of tale or other suitable substance.
Around and abutting against the outer sides of this furnace or heated chamber a, a,
the thermo-electric bàrs or couples f, f, are arranged radially, or otherwise, in tiers
or in sections, as before mentioned, so that they may receive the heat given out by
the refractory material while the fire is burning.
An entirely novel and distinctive feature in this particular apparatus is the
manner in which the fire chamber A is constructed. It is provided with a vertical
opening which extends from top to bottom, and is provided with a door or doors

page_text: j, j', for obtaining access to the interior of the fire-place and ascertaining from time
to time the condition of the fire and for regulating the same. These doors serve
also for facilitating the removal of clinkers, and for general stoking purposes. The
fire chamber is also provided with fire or grate bars k, k, as well as with vertical
bars 1, l, at the vertical opening, and some of these bars are made moveable. The
fire chamber A. is provided likewise with a lid or cover m at the top and chimney
n to carry off the products of combustion and smoke. The doors j, j',
made of iron lined with fire-clay or some similar material, and some of the panels of
the doors may have openings made therein and covered with talc, so that the
attendant may be enabled to see the state of the fire and how the combustion
is proceeding without opening the door. The ash pit is also provided with
doors o, o.
may be
It will be seen on referring to Fig. 12, that the bars ff, are divided into five
vertical sets arranged radially round the fire place A. Each layer of bars of which
these vertical sets are composed is divided from those above and below it by means
of segmental pieces g, made of earthenware or some other suitable non-conducting
material, and at each end of these segments are the blocks or projections g¹, g', for
supporting the segmental piece immediately above so as to take the weight off the
bars ff, as in the former instance. Each vertical set of bars is held together by
means of pairs of rods, which pass through the blocks g¹, as at h, in Fig. 1, so that
any of the vertical sets of bars can be removed without interfering with the others,
and the whole apparatus is held together between top and bottom plates which are
secured together by the binding or tie rods h¹, h¹.
The arrangement of apparatus shewn at Figures 11 and 12 will be found con-
venient when great power is required, and when the apparatus is intended to be
stationary; but the arrangement shewn at Figures 1 and 2 will be found more con-
venient when only a moderate power is required, and it can be moved with greater
facility and less liability to derangement than the other. In some cases, as when it
becomes necessary to remove the apparatus from one place to another, it is desirable
to support and hold steady the outer ends of the thin positive bars i, i. This is
effected by connecting them to wooden uprights p, p, as shewn at Figures 9 and 10.
In these Figures the outer ends of the thin metal bars i, i, are shewn as being
clamped or nipped between two wooden bars, which are drawn together by means
of short screw bolts, but if preferred the projecting ends of the thin positive bars i, i,
may be temporarily attached to the sides of wooden uprights by means of pins, nails,
or screws.
Having now described our Invention of "Improvements in Electrical Apparatus,"
and having explained the manner of carrying the same into effect, we claim as
the Invention secured to us by Letters Patent as aforesaid.
First. Constructing the central heating chamber of a cylindrical or other tube
made of any suitable material, around the outside of which the thermo-electric bars
are arranged in such a manner that their inner ends shall abut against the heated
surface of the said chamber, as herein set forth. We claim the use of the central
heating chamber in the manner and for the purpose described, whether it be heated
by a gas burner or by any liquid or molten heating medium, such as oil, or an easily
fusible metal, or by means of coke, coal, or other solid or liquid fuel. We further
claim lining the gas burner with wire gauze, as and for the purposes herein set
forth, and also constructing the heating chamber with a vertical opening (closed by
doors). When the said chamber is heated by solid fuel, as shewn and described in
reference to Figures 11 and 12.
Second. We claim constructing the pile of bars in horizontal or vertical sections
as and for the purposes herein set forth, and also dividing the layers of bars from
cach other by means of insulating discs or plates provided with projecting blocks to
support the superincumbent weight of the pile, and relieve the bars from undue
pressure, as above described.
Third. We claim the mode or modes herein set forth of casting or forming the
negative and positive bars. We claim particularly the mode or modes shewn and

page_text: described of forming and treating the ends of the positive or of the negative bars
(as the case may be), and of connecting the one with the other.
In witness whereof, we, the said Cecil Wray and Leonard Wray, junior, have
hereunto set our hands and seals, the Fifth day of September, in the year of
our Lord One thousand eight hundred and seventy-six.
CECIL WRAY..
(L.S.)
L. WRAY, JUN³. (L.S.)