Improvements in the Heating of Gases by Electricity.
Year: 1894

page_text: Date of Application, 14th Feb., 1894-Accepted, 10th Mar., 1894
COMPLETE SPECIFICATION.
Improvements in the Heating of Gases by Electricity.
FI, WILLIAM DONALDSON, of 33 South Street, Thurloe Square, South Kensington,
in the County of Middlesex, Civil Engineer, do hereby declare the nature of this
invention and in what manner the same is to be performed, to be particularly
described and ascertained in and by the following statement :-
My invention relates to the heating of gases by electricity and consists of means,
whereby the communication of temperature to the gases to be heated may be
affected in such a way, that the heating effect upon the gases increases as the gases
flow and in proportion, as their temperature rises.
To effect this I pass the gases to be heated through a tube or elongated chamber,
within which I arrange a wire, or partial conductor of an electrical current,
insulated from the said tube or chamber, but in naked contact with the gases to be
heated. 1 may arrange the said wire or conductor as a coil or in any other
disposition, to afford a large surface of contact to the passing gases.
arrange the said wire or conductor of larger section where the gas in its coolest
condition enters the said chamber and is first in contact with said heating wire or
conductor, and I diminish the section of the said wire or conductor to increase the
resistance to the flow of the said electrical current, towards that part of the tube
or chamber from which the heated gas eventually escapes or is discharged.
I may produce this variable section of wire or conductor either by a homogeneous
wire rod or strip gradually tapering from one end to the other, or I may make
such conductor of successive parts of variable section, connected to one another for
electrical continuity,
Or alternatively, I may make such wire or conductor of a series of various metals
of different electrical resistance to the passing current, so as to develope a degree of
heat therein as before described.
Having now particularly described and ascertained the nature of the said inven-
tion, and in what manner the same is to be performed, I declare that what I
claim is :-
1st. A method for the heating of gases by electricity, by passing the said gases
through an elongated chamber or tube, in contact with an internal coil of wire or
other partial conductor carrying an electric current, the resistance and resulting
temperature of said conductor being arranged so that it is of least intensity at the
po nt where the gas enters and of greatest intensity where the heated gas issues.
2nd. A coil of wine, rod, strip or other conductor, partially conducting an
electric current and tapered in its section from largest area where the gas to be
heated is first in contact with it, to smallest area and consequently highest
temperature where the gas issues, in combination with an enclosing elongated
chamber or tube, to conduct the gas through the same, in contact with the said
conductor substantially as described.
3rd. In combination with a surrounding elongated chamber or tube a coil of wire,
rod, strip or other conductor, insulated therefrom, and partially conducting an
electric current so made that it offers a greater resistance to the passing current
where the warmed gas issues, than at the point where the gas to be warmed enters,
substantially as described.
C
1004
FELL & WILDING,
1, Queen Victoria Street, London, E.C., Agents for the Applicant.