Year: 1886

page_text: GODOD
I BENJAMIN JOSEPH BARNARD MILLS of the firm of Harris and Mills of
23 Southampton Buildings in the County of Middlesex, Patent Agent do hereby
declare the nature of this invention, a communication to me from abroad by Nelson
Williams Perry of Norwood in the County of Hamilton and State of Ohio, in the
United States of America, 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 Figures and letters marked
thereon that is to say :-
Figure 1 is an elevation of one way of embodying the invention; M, is a base for
the standards F, E;-R, R, are wires running from the binding screws H, H, to
the battery P, through the alarm bell N; A is a flat bar composed of a piece of
platinum or palladium and a gold plating; B is a contact point on the tongue D.
Figure 2 is an elevation of another way of embodying the invention; T, T, are
tongues having points dropping into a film of oxide of palladium S, in the trough W.
Figure 3 is an elevation of another way of embodying the invention; n is a
piece of palladinized charcoal held near the end of a thermal pile a, with wires r r
running to a binding post H on the base M of a relay m. Similar letters of
reference indicate like parts.
The invention relates to the detection of the presence of marsh gas and other
hydro-carbon gases, and more especially to the presence of fire damp and the gases
of natural gas wells, and consists essentially of an open electric circuit and a metal
or the salts of a metal so placed in the circuit that it shall, by change of position,
character, or temperature, by reason of its having occluded hydrogen or a
combustible hydro-carbon gas, or by the action of said gases on the salt, close
said circuit.
The invention is based upon these chemical facts:
First;
That platinum and palladium occlude large quantities of hydrogen and
hydro-carbon gases, and by so occluding these gases their bulk is increased.
Second; That the oxide of palladium when in the presence of hydrogen and
hydro-carbon ases, at ordinary temperature, is reduced to the metallic state, and

page_text: に
A
-
that the oxide of palladium is a non-conductor of electricity while the metal
palladium is a good electric conductor.
Third: If charcoal be platinized or palladinized, it will in the presence of
hydrogen or combustible hydro-carbon gases, become heated.
The invention embodying the first two of these facts, consists in an open electric
circuit in combination with platinum or palladium, or their salts, constituting one
portion of the circuit, and adapted to close the circuit by reason of the increase in
its volume, when it shall have occluded a sufficient quantity of hydro-carbon gas.
One form of this electrode of platinum or palladium is a flat ribbon, one side of
which is plated with gold or any other conducting metal not acted upon by these
gases, and the other side is uncovered. This piece of metal shown in Figure 1 will
by the increased length of the uncovered side due to the occlusion of the hydro-
carbon gases, be bent up, as shown in the drawing by the dotted lines and so close
the circuit.
One form by which the oxide of palladium may be used is shown in Figure 2
where the wires are shown as dipping into the trough filled with said oxide; when
the oxide by reason of the hydrogen, or hydro-carbon gases reducing action becomes
metallic, the open circuit becomes a closed circuit.'
An embodyment of the invention is shown in Figure 3, and is based on the third
of the aforementioned chemical facts.
Figure 3 shows a block of platinized charcoal held securely near one end of a
thermal pile.
When the charcoal becomes heated by reason of its properties in presence of said
gases, one end of the thermal pile becomes heated, a current passes through it,
putting into action the .electro-magnet of the relay m shown in Figure 3, and the
said electro-magnet moves an armature which closes an open circuit.
When the presence of fire damp or other dangerous gas may be suspected, the
bi-metallic bar A, or platinum or palladium and gold, Figure
is included in an
electric circuit as shown, or a film of the oxide of palladium S, is held in a
trough W, and included in an electric circuit, or a piece of palladinized charcoal n
Figure 8 is held near the end of a thermal pile a having conducting wire running
to the relay m which is connected up in an electric circuit. All these electric
circuits include an alarm bell.
If now, any of said gases accumulate in any of said places in any thing like
dangerous. quantity, the metal or the oxide or the charcoal, by reason of their
properties in presence of said gases, will close said circuits which being connected
with any suitable alarm, gives notice of the presence of said gases.
:
Having now particularly described and ascertained the nature of the said
invention and in what manner the same is to be performed, I declare that what
I claim is :-
In a detector of fire damp and other dangerous hydro-carbon gases, the
combination of an open electro circuit, a substance that occludes said gases, so
placed in relation to said circuit as to close it by reason of said occlusion or
reduction, and an alarm bell or signal; substantially as described.
B. J. B. MILLS.
By Harris & Mills,
23, Southampton Buildings,
Agenta.