IMPROVED CONSTRUCTION OF THERMO-ELECTRIC PILES
Year: 1884

page_text: We JOHN LEA of 75 Arlington Road, Camden Town, Electrical Engineer and
GEORGE CRAWFORD HARVEY of 34 Great St. Helens, London, Gentleman, dọ
hereby declare the nature of our said invention for " IMPROVED CONSTRUCTION OF
THERMO-ELECTRIC PILES," to be as follows:-
This invention has for its object. Improvements in the manufacture of thermo-
electric piles generally.
In thermo-electric piles at present constructed the metal or mixture of metals
combine with the atmosphere or the oxygen thereof, and become brittle, liable to
breakage, of great resistance, and ultimately useless.
Now we effectually prevent the metal from combining with the gases of the
atmosphere by hermetically enclosing it in the other metal forming the pair in such
a manner that the pair touch. each other at the part where the heat is applied and
also for a short distance therefrom. The outer and inner metals have then a space
between them which is filled with some insulating material such as asbestos.
This outer metal may be made in two parts screwed or fixed together, one part,
the outer, forms a cap to protect the inner one which is insulated therefrom; at the
same time it forms the connections between itself and the inner metal of the next
pair. The connection of the next pair come through an insulated hole of the cap
of its outer metal and thus the oxydizable metal is protected in every way from
injury (atmospherical and other): Delta metal gives good results with the known
mixture of antimony and zinc. This Delta metal is cast or shaped into the form
of a thimble or bottle with a screw neck. Into this we cast the antimony and zinc
we then screw or fix a cap of the same metal thereon this being insulated from the
antimony and zinc to close it from the surrounding atmosphere and to prevent its
evaporation.
When a composition of antimony and zinc is used in connection with bismuth,
we form the antimony and zinc in the same manner as with the Delta metal.
We then cast or place the bismuth therein as in the above case, (the antimony
and zinc) with insulation as above described. We then enclose the whole in a
casing of any other metal such as iron etc. and insulated therefrom to bermetically
seal the other metals from the atmosphere and protect them from breakage or
evaporation.
H. GARDNER,
166, Fleet Street, London,
Agent for the Applicants.

page_text: Improved Construction of Thermo-electric Piles.
We JOHN LEA of 75 Arlington Road, Camden Town, London, Electrical
Engineer and GEORGE CRAWFORD HARVEY of 34 Great Saint Helens, London,
Gentleman, do hereby declare the nature of our invention for "IMPROVED CON-
STRUCTION OF THERMO-ELECTRIC PILES" 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 improvements in the manufacture of Thermo-
Electric piles generally.
In Thermo-Electric piles at present constructed the metal or mixture of metals
combine with the atmosphere or the oxygen thereof and become brittle, liable to
breakage, of great resistance and ultimately useless.
Now we effectually prevent the metal from combining with the gases of the
atmosphere by hermetically enclosing it, in the other metal forming the pair, in
such a manner that the pair touch each other at the part where the heat is
applied and also for a short distance therefrom the outer and inner metals have
then a space between them which is filled with some insulating material, such as
asbestos.
This outer metal may be made in two parts screwed or fixed together at one
part, the outer forms a cap to protect the inner one which is insulated therefrom
at the same time it forms the connection between itself and the inner metal of the
next pair. The connection of the next pair comes through an insulated hole of the
cap of its outer metal and thus the oxidizable metal is protected in every way from
injury (atmospherical or other).
Delta metal gives good results with the known mixture of antimony and zinc.
This Delta metal is cast or shaped into the form of a thimble or bottle with a screw
neck. Into this we cast the antimony and zinc, we then screw or fix a cap of the
same metal as the bottle or thimble thereon this being insulated from the antimony
and zinc closing it from the surrounding atmosphere and preventing its evaporation
or volatilization.
When a composition of antimony and zinc is used in connection with bismuth
we form the outer case of antimony and zinc in the same manner as with the
Delta metal, we then cast or place the bismuth therein (instead of as in the above
case the antimony and zinc) with insulation as above described, we then enclose
the whole in a casing of any other metal or material such as iron etc insulated
therefrom to hermetically seal the metals forming the element from the atmosphere
and protect them from breakage or evaporation.
In place of asbestos any silica or vitreous insulation which is capable of standing
great heat may be used.
In the accompanying drawings Figure 1 shows a thermo-electric pair or element.
constructed according to our, invention in which A is the outer case formed of
that metal or constituent of the thermo-pile which is not injured or volatilized
by the atmosphere or the application of the heat necessary for working the
thermo pile.

page_text: B is the other metal or substance of the thermopile which it is desirable to
protect. C is the insulation between the two metals. The outer case A is
preferably screwed for the reception of the cap D of the same material as said
outer case. A metallic rod E passes through the cap D (but is insulated there-
from) into the inner metal and forms one terminal of the thermopile, the cap D
forming the other.
Figure 2 shows a modification suitable for a thermo-electric pile in which both
metals or substances are liable to injury or melt at a low temperature as antimony
and zinc composition and bismuth. The outer metal A is surrounded by a case F
the
space G between them being filled with asbestos or other suitable insulating
material.
The pairs may be made cylindrical or of any suitable shape.
Having now described and ascertained the nature of our said invention and in
what manner the same is to be performed we declare that what we claim is
The improved construction of thermo electric element hereinbefore described and
substantially as shown in the annexed drawings whereby the metals or substances
(or one of them) forming the thermo-electric pile are protected from the atmosphere,
from breakage etc.
The 28th day of August 1885.
H. GARDNER,
166, Fleet Street, London,
Agent for the said J. Lea & G. C. Harvey.