Improvements in Gas Stoves.
Year: 1890

page_text: Date of Application, 17th Feb., 1890-Accepted, 22nd Mar., 1890
COMPLETE SPECIFICATION.
Improvements in Gas Stoves.
I, CHARLES CLAMOND, of 15 Rue Picot Paris, France, 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 :-
Apparatus for heating by combustion of gas are of three kinds, 1° those that act by
circulation of the hot products of combustion-2° those which utilise also the
radiation of the flame, and 3° those which utilise the radiation of bodies heated red
hot by the combustion.
It is to the last of these that my invention applies, the apparatus which I am
about to describe being arranged to utilise fully the heat of combustion, and at the
same time being of a practical character and agreeable appearance.
For this purpose, I secure in the fire the highest possible temperature by admitting
only sufficient air for combustion, previously heating this air and bringing it in
contact with the gas at many points. In this fire I heat a refractory body to a very
high temperature, which radiates a portion of its heat but not enough to cool the
medium in which it is placed, the radiation being effected through a screening
medium. The products of combustion, which escape at a high temperature, are not
cooled by any admixture of cold air; they impart most of their heat to the walls of
the passages in which they circulate, and this heat is taken up by the air surrounding
these walls, the air thus heated being directed as may be desired.
Figure 1 of the accompanying drawings is a vertical section of apparatus according
to my invention.
The firo consists of thefollowing parts,-
,-a. thin refractory plate C with holes c for
passage of flame through it, or it may be a grating as shewn by Figure 2,-another
thin refractory plate B, usually of metal that does not readily melt, such as iron, nickel
or alloys thereof; this plate is perforated by holes and stands parallel to C, a thick
wall A of refractory material which is a bad conductor of heat, pierced with holes a
and standing parallel to B and C,-a chamber D under these plates supplied with a
mixture of air and gas by a bunsen tube T or several of these. The cover of D is
perforated by holes d through which the mixture of air and gas passes to the space
between B and C. There might also be holes opening to the space between C
and A but this is rendered unnecessary by the holes c. The combustible mixture
between B and C burns only where the holes b admit air to it, producing flames
directed towards the plate Cheating its front surface. Unburnt portions of the
gaseous mixture pass through the holes c, and, being supplied with heated air passing
through the holes a, these portions burn heating the back of C.
The plate C thus heated on both sides radiates part of its heat on B which being
also heated by the flames behind it, becomes red hot and radiates its heat around.
The plate B serves also to moderate the radiation from C, which unless it were thus
screened would become more or less cooled by the entrance of excess of air, cooling
also the products of combustion. Through the holes b can be seen bright parts of
standing out as it were on the cherry red ground of B. This is pleasant to the eye
and gives the sensation of a bright open fire. The effect can be varied by varying
the forms and arrangements of the holes b, which may be round, rectangular, or
horizontal or vertical slots or combinations of these. The plate C radiates also on the
wall A which being thick and a bad conductor takes up little heat, but this heat is
given to the air which passes through A, after entering at Z and passing up and over
the plate q, heated on its way by the walls N, A the plate 9 and the surfaces of the
The products of combustion pass by the flues M to the chimney F, and these
flues being enclosed in a casing H heat air entering that casing from which it may be
led to suitable outlets for warm air.
holes a.

page_text: As shewn in Fig. 3 the plate B may be in the frame of a fire door which can be
opened for lighting the gaseous mixture.
Fig. 4 is a perspective view of one form of the apparatus, the shape and size of
which may be varied as desired.
I would observe that in many gas stoves a radiating surface is heated, this surface
sometimes presenting filaments of asbestos or pieces of metal or other refractory
material, but in all these cases there is free access of air which prevents the surface
from becoming intensely hot and cools the flame. According to my invention, on
the other hand, the combustion takes place in a space to which is admitted only the
air necessary for combustion, this air being previously heated, so that there is great
intensity of combustion and proportionally great heating effect.
The plates A B, C instead of being flat may be of arch form, convex or concave, or
may be in the form of concentric cylinders radiating all round, so that the whole
forins a circular stove.
Having now particularly described and ascertained the nature of this inven-
tion and in what manner the same is to be performed I declare that what I
claim is :-
1. In a gas stove, the combination of three parallel refractory perforated plates, the
middle one of which is heated on both sides by gas flames supplied with heated air
admitted through the perforations of the others, substantially as and for the purposes
set forth.
2. The construction of gas stove substantially as described and illustrated by the
accompanying drawings.
Dated this 17th day of February 1890.
ABEL & IMRAY,
Agents for the Applicant.