WARM AIR FIRE GRATE
Year: 1884

page_text: I JOHN GRUNDY of N° 30 Duncan Terrace City Road London and Tyldesley
near Manchester Heating apparatus Manufacturer do hereby declare the nature of
my invention for WARM AIR FIRE GRATE to be as follows :—
A fire grate being made in the form of a stove the back of which is Semicircular
in shape with gills behind and smoke nozzle on top all cast in one piece The same
can be attached to any design if a register stove front an Iron pipe is inserted in
the smoke nozzle and carried for any length up the Chimney and the Chimney for
the said distance being used as a warm air chamber for supplying warm air to any
number of rooms, the connection between the air chamber and smoke flue is
separated by an iron collar fitted over the top of pipe and made air tight with
cement. Warm air is admitted into the rooms by gratings in the walls.
Dated this 27th day of March 140A

page_text: I JOHN GRUNDY, of 30 Duncan Terrace, City Road, London, Middlesex, and
Tyldesley near Manchester, Lancashire, Heating Apparatus Manufacturer, do
hereby declare the nature of my invention for "A WARM-AIR FIRE GRATE," and
in what manner the same is to be performed, to be particularly described and
ascertained in and by the following statement :-
The object of my invention is the introduction of an improved warm-air fire
grate, and is intended to be more particularly applicable to what are known as open
fire grates.
According to my invention I construct the back of my improved grate or stove
with gills, after the manner of the well known Gill air warmer, projecting from its
rear surface into a warm air chamber which may be conveniently constructed in
the brick work behind the stove.
The back is of metal and is made, by preference; in one piece with its sides and
smoke nozzle. The latter enters the throat of the ordinary chimney, the throat of
which is utilised as both smoke_flue_and_warm_air_duct in the following manner.
Upon the smoke nozzle before mentioned I erect a smoke pipe, of iron or other
suitable material, in sectional area less than that of the chimney throat, so leaving
an annular passage or duct of sufficient capacity to pass the desired quantity of
warm air. The smoke pipe is continued up the chimney for a suitable distance,
and its top is connected, air-and smoke-tight, to the chimney proper. The warm
air passes from the annular duct into the room along proper air passages, and
through suitable controllable valves, or their equivalent, constructed and fixed in
the chimney breast, and (when necessary) in the walls.
In order that my invention, and the means by which the same is put into
successful operation, may be thoroughly understood, I will now describe the same,
referring to the accompanying drawings which are to be taken as part of this
specification and read therewith, and in which corresponding parts are marked
throughout with the same reference letters.
Figure 1 is an elevation of my improved warm air grate fixed; Figure 2 is a
sectional elevation taken at the line y-z, Figure 1; and Figure 3, a plan partly in
section, taken at the line vw, on Figure 2.
A is the ordinary front of the stove or grate, B the bars, and C the bottom grate.
D is my improved back made with its sides, d, and arch, d, in one piece. On its
rear or outer surface are a series of gills, d³, running preferably in a vertical
direction, and either rectilinear or serpentine. E is the chamber into which the
cold air is admitted from the external atmosphere, and where it is warmed by
coming into contact with the heated surface of the grate back, D, and its gills, d³.
F is the cold air admission duct, of a suitable sectional area, and f a grate or it may
be a valve. The consequence of the increased area of the grate back is that the
desired quantity of air is warmed without it being necessary to keep the back at 50
high a temperature as would burn said air. Hence the fuel in the grate can be
economically consumed, and the necessity of keeping up extravagant fires avoided.
D' is a nozzle carrying a short smoke flue, G, fixed in the throat of the
chimney, H, and producing an annular space I, surrounding the smoke flue G, and
is at once a continuation of the warming chamber E and a warm air duct. The
space I is always made of a capacity sufficient to pass the desired volume of warm
air. The top, I, of the smoke flue is connected to the chimney proper, both smoke-
and air-tight, in any convenient way. I find that a flat plate, Is, let into the brick

page_text: work and embracing the top of the flue, makes, when properly cemented, an
efficient joint. The air duct, I, communicates with the room to be warmed through
a passage, J. The passage may be a simple one piercing the chimney breast, as
shown in Figure 1, or it may be continued round the room, and several openings,
controlled by suitable valves as at K, for the regulated admission of warm air,
made therein.
I would have it understood that I do not restrict my invention to open fire
grates, as it can be advantageously applied to various types of closed-fire warm-air
heating apparatus.
Having now particularly described and ascertained the nature of my said
invention, and in what manner the same is to be performed, I declare that what
I claim is:
In a warm air fire grate the use of the gills, d, projecting from the rear face of
the fire back with the air warming chamber, E, in combination with the inner
smoke flue G and duct I, the latter delivering the warmed air into the room, as
described with reference to the accompanying drawings.
Dated this 4th dow of December 1884
PHILLIPS & LEIGH,
Patent Agents,
22, Southampton Buildings,
Chancery Lane, W.C.,
Agents for the Applicant.