IMPROVEMENTS IN REGISTER STOVES AND OTHER GRATES FOR HEATING AND VENTILATING ROOMS
Year: 1879

page_text: LETTERS PATENT to Robert Henry Griffin, of St. Pancras, in the County of
Middlesex, Gentleman, for the Invention of "IMPROVEMENTS IN REGISTER
STOVES AND OTHER GRATES FOR HEATING AND VENTILATING ROOMS."
PROVISIONAL SPECIFICATION left by the said Robert Henry Griffin at the
Office of the Commissioners of Patents on the 1st December 1879.
ROBERT HENRY GRIFFIN, of St. Pancras, in the County of Middlesex, Gentleman.
"IMPROVEMENTS IN REGISTER STOVES AND OTHER GRATES FOR HEATING AND
VENTILATING ROOMS."
The object of this Invention is to more completely utilize the heat generated by
the fuel consumed in such stoves or fire-places, and thereby to economise fuel, to
provide for the circulation of a more constant and larger supply of fresh air into
the rooms where such stoves are fixed, to heat or warm such air prior to its
entering the rooms, and to secure a more perfect ventilation thereof, which object I
attain as follows:
My improved grate is somewhat similar in general appearance to the ordinary
register stove, but it is provided with a moveable blower and ventilator directly
over the fire. The fire-place is encased with iron, and lined with Stourbridge or
other similar lumps, and has an iron cover over the top thereof, thus forming a kind
of furnace. The opening into the flue is over the front part of the fire, instead of
the back part, as is usual. The said flue consists of a pipe or tube for conveying
the products of combustion to the chimney.
An air-chamber is formed at the back and sides of the grate, and is covered in
with an iron plate. A current of fresh air is introduced into the lower part of the
said chamber, which in its upward course takes up the radiated heat; this air being
thus heated or warmed enters the room through ventilators provided in the front of
the upper part of the grate, rises thence to the ceiling, and then descends to the
front of the fire, through which it passes, taking with it a part of the vitiated air
from the room, and thence passes through the said flue into the chimney. The
warmed and vitiated air of the room also passes through a flue under the grate to
the back of the fire-place, and is delivered in jets over such fire for promoting
combustion and assisting ventilation.
The ventilators and flues may be provided with sliding regulators or dampers,
and the flue pipe is fitted with a moveable door for convenience in cleansing the
said flue and chimney.
My improved grate combines the advantages of the closed hot-air stove with
those of the ordinary register stove, with the important additional advantage of
improved ventilation.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Robert Henry Griffin in the Great Seal Patent Office on the 31st May
1880.
ROBERT HENRY GRIFFIN, of St. Pancras, in the County of Middlesex, Gentleman.
"IMPROVEMENTS IN REGISTER STOVES AND OTHER CRATES FOR HEATING AND
VENTILATING ROOMS."
The object of this Invention is to more completely utilize the heat generated by
the fuel consumed in such stoves or fire-grates, and thereby to economise fuel, to
provide for the circulation of a more constant and larger supply of fresh air into
the rooms wherein such stovės are fixed, to heat or warm such air prior to -its
entering the rooms, and to secure a more perfect ventilation thereof, which object I
attain as follows :-
In order that my said Invention may be more fully understood, and be moro readily
performed, I will explain the same with the aid of the accompanying Drawing,
which forms part of this Specification, reference being made thereto by the numerals
and letters marked thereon. The same index letters refer to the same parts in each
Fig. of the said Drawing.
Fig. 1 is a front elevation of my improved fire-grate; and Fig. 2 is a vertical
section through the same on the line A, B, Fig. 1.
The fire-place may be either encased with iron or be formed entirely of fire-clay,
that is, the hearth a, sides a¹, back a³, and cover a³ over the fire, as shown in the
Drawing, by which means the properties of the air are not injured.
A covered air-chamber c is formed at the back and sides of the grate. A current
of fresh air is introduced into the lower part of such chamber, say, at c', which air
in its upward course takes up the radiated heat, and thus heated or warmed enters
the room through the ventilators d, Fig. 1, rises thence to the upper part of the
room, and then descends, nixed with the vitiated air of the room, and enters the
fire at fand the back flue g¹ at y. I also perforate the bottom of the grate for
the admission of such air to the fire. This vitiated air thus withdrawn from the
room is then delivered in jets around, in, and over the fire; the oxygen of such air
combines with the unconsumed gases, promoting their combustion, and largely con-
suming the smoke. After passing through the fire such air with the products of
combustion enter and pass through the tube or flue to the chimney, with which
such tubular flue is connected. This flue h, instead of being at the back of the
fire-place as usual, is placed at the front thereof and directly over the fire.
.
By passing the heated products of combustion through the tubular flue / an
essential gain of heating surface (hitherto lost) is obtained. The upper part of the
flue is fitted with a moveable plate or valve h¹, operated by turning its handle h³,
to regulate the draught or current and to conserve heat, also for convenience in
sweeping the chimney.
The ventilators and flues may be provided with sliding regulators or dampers.
My improved grate combines the advantages of the closed hot-air stove with
those of the register-stove or ordinary fire-grate, with the additional advantages of
improved ventilation and partial consumption of smoke.
Having thus fully described and ascertained the nature of uny said Invention,
and the method of performing the same, I wish it to be understood that I do not
clain the formation of an air-chamber at the back of the grate per se, as my Inven
tion; also that I do not restrict myself to the precise forms and dimensions of the
several parts as now illustrated, they being capable of much variation and numerous
modifications, as when applied to stoves or grates of different kinds without departing
from the principles and main characteristics of the Invention; but what I claim as
new and desire to secure by the herein before-mentioned in part recited Letters
Patent is,―
Firstly. The method of covering in the fire-place.

page_text: Secondly. The method of conveying the products of combustion from the front
part of the fire-place through a tubular flue to the chimney.
Thirdly. The method of regulating the draught or current through the said
tubular flue.
Fourthly. The method of withdrawing vitiated air from rooms and utilizing the
same.
Fifthly. The method of forming an extended air-chamber at the back and sides
of fire-grates as a means of obtaining a greater heat-radiating surface for warming
the air in its passage to the rooms.
Each and all these claims substantially as herein described and illustrated in tho
Drawing.
In witness whereof, I, the said Robert Henry Griffin, have hereunto set my
hand and seal, this Twenty-eighth day of May, in the year of our Lord One
thousand eight hundred and eighty.
-
ROB. H. GRIFFIN. (L.S.)