Improvements in Regulating Combustion in Open Fire Places.
Year: 1888

page_text: Date of Application, 16th Nov., 1888
Complete Specification Left, 2nd Aug., 1889--Accepted, 14th Sept., 1889
PROVISIONAL SPECIFICATION.
Improvements in Regulating Combustion in Open Fire Places.
We GEORGE GORDON BRODIE of Catherine Street Aston near Birmingham in the
County of Warwick Ironfounder and JAMES DAMREL PRIOR of No. 143 Isledon
Road Finsbury Park London in the County of Middlesex Manager do hereby
declare the nature of this Invention to be as follows:-
Our invention has for its object to provide the means of effecting complete
control of the combustion of the fuel in open fire places and consists of the
construction and arrangement of parts hereinafter described.
In the inner edge of each of the inclined jambs of the recess at the bottom
of which the fire bars or fire grate proper is situated we make a vertical groove
extending from the upper part of the said jambs to their bottom.
These grooves are a little in front of the fire grate. In the said grooves a light
metallic plate preferably of sheet iron sildes vertically. This plate is either flat or
angular or convex or of such other figure according to the figure of the front of the
grate that in descending to its lowest position it will pass in front of the fire grate
without obstruction. By racks in the grooves of the jambs and projections on the
edges of the said plate it can be fixed in any required position. In the upper part of
the recess formed by the jambs is a fixed plate preferably ornamental of the same
configuration in horizontal section as the sliding plute. This fixed plate is situated.
a little in front of the grooves in the jambs so that when the sliding plate is
raised to its highest position the whole of it except its lower edge passes behind
the said fixed plate and is in that position nearly out of sight. When the sliding
plate is in this its highest position has no effect on the rate of combustion of
the fuel in the grate. When however it is drawn down more or less from behind
the fixed plate it contracts more or less the space through which air passes to the
chimney. It then acts as a draw plate or blower and rapidly induces more rapid
combustion. Its action as a draw plate or blower is most powerful when its lower
edge is at the same level as the top bar of the grate. By lowering the sliding
plate still further the access of air is more and more restricted until when the
said plate has reached its lowest position and its bottom edge rests on the framing of
the closed ash pit or ash pan the supply of air is practically cut off only such an
amount of air passing to the grate as can gain access thereto by passing between the
parts approximately in contact. By lowering the sliding plate to nearly its full extent
an amount of air may be admitted to the fuel only sufficient to keep up a low or
smouldering combustion. The fire may be kept thus burning for a long time and
should a vigorous fire be suddenly required the intensity of the combustion may be
very rapidly increased by raising the sliding plate to a height which uncovers the
front of the grate.
By our invention the rate of combustion of the fuel in the grate may be varied
at pleasure to an extent and with a rapidity hitherto unattainable.
Although in ordinary cases we make the sliding plate in one piece yet in some
cases we make it of two or more pieces sliding telescopically one behind the other.
In this arrangement the raised parts of the plate occupy loss space than when the
plate is made in one piece.
Dated this 16th day of November 1888.
W. T. WHITEMAN,
Agent for the Applicants.

page_text: COMPLETE SPECIFICATION
Improvements in Regulating Combustion in Open Fire Places.
We GEORGE GORDON BRODIE of Catherine Street Aston near Birmingham in
the County of Warwick Ironfounder and JAMES DAMREL PRIOR of No. 143 Isledon
Road Finsbury Park London in the County of Middlesex Managor do hereby
declare the nature of our invention and in what manner the same is to be
performed to be particularly described and ascertained in and by the following
statement :-
Our invention has for its object to provide the means of effecting complete
control of the combustion of the fuel in open fire places and consists of the construction
and arrangement of parts hereinafter described.
In the inner edge of each of the vertical jambs of the recess at the bottom of
which the fire bars or fire grate proper is situated we make a vertical groove extending
from the upper part of the said jambs to their bottom. These grooves are a little iu
front of the fire grate or front fire bars. In the said groove a light metallic plate
preferably of sheet iron slides vertically. This plate is either flat or angular or
convex or of such other figure according to the figure of the front of the grate that
in descending to its lowest position it will pass in front of the front fire bars of the
grate without obstruction. By racks in the grooves of the jambs and projections on
the edges of the said plate it can be fixed in any required position. In the upper part
of the recess formed by the jambs is a fixed plate preferably ornamental of the same
configuration in horizontal section as the sliding plate. This fixed plate is situated a
little in front of the grooves in the jambs so that when the sliding plate is raised to
its highest position the whole of it except its lower edge passes behind the said fixod
plate and is in that position nearly out of sight. When the sliding plate is in this
its highest position it has no effect on the rate of combustion of the fuel in the grate.
When however it is drawn down more or less from behind the fixed plate it contracts
more or less the space through which air passes to the chimney. It then acts as a
draw plate or blower and rapidly induces more rapid combustion. Its action as a
draw plate or blower is most powerful when its lower edge is at the same level as the
top bar of the grate. By lowering the sliding plate still further the access of air is
more and more restricted until when the said plate has reached its lowest position and
its bottom edge rests on the framing of the closed ash pit or ash pan or on the hearth
the supply of air is practically cut off only such an amount of air passing to the
grate as can gain access thereto by passing between the parts approximately in
contact.
By lowering the sliding plate to nearly its full extent an amount of air may be
admitted to the fuel only sufficient to keep up a low or smouldering combustion.
The fire may be kept thus burning for a long time and should a vigorous fire bo
suddenly required the intensity of the combustion may be very rapidly increased
by raising the sliding plate to a height which uncovers the front of the grate.
By our invention the rate of combustion of the fuel in the grate may be varied at
pleasure to an extent and with a rapidity hitherto unattainable.
•
Figures 1, 2 and 4 of the accompanying Drawing represent front elevations and
Figure 3 represents a side elevation of an open fire place to which our invention is
applied, the said fire place being furnished with a firo grate having an angular
front, the sliding draw plate or blower having a corresponding figure; but our
invention may be applied to fire places having fire grates with flat, curved or other
shaped fronts.
In the several Figures of the Drawing the sliding draw plate or blower is
marked a.
In Figure 1 the sliding draw plate or blower is raised to its highest
position being concealed within the canopy or fixed plate 6 of the fire place as
indicated by the dotted lines a in the said Figure 1. In Figures 2 and 3 the sliding
draw plate or blower a is represented partly drawn down with its lower edge brought
onto a level with the top of the front fire bars c of the grate and in Figure 4

page_text: b
the sliding draw plate or blower a is represented lowered to its full extent and
resting on the hearth of the fire place. The said sliding draw plate or blower is
moved by the knob or projection marked d and has the same angular figure as
the front bars c of the fire grate and the canopy b over which bars and within which
canopy it slides. The vertical edges of the sliding draw plate or blower a work in
vertical grooves extending from the upper parts of the jambs of the fire place to
their bottoms and by means of racks in the said grooves of the jambs and projections
on the edges of the said plate a it can be fixed in any required position. The canopy
of the fire place is situated a little in front of the grooves in the jambs so that when
the sliding draw plate or blower a is raised to its highest position as indicated in
dotted lines at a Figure 1 and at a, a Figure 3 the whole of it except the knob or
button d by which it is moved passes behind the said fixed canopy or plate b and in
that position is concealed as represented in Figure 1. The sliding plate a in this
position has no effect on the rate of combustion of the fuel in the fire grate. When
the sliding plate or blower a is drawn down from behind the canopy b into the position
represented in Figures 2 and 3 its lower edge is situated at the same level as the top
of the front fire bars c and the front of the fire grate is covered and the air space to
the chimney is thereby contracted. The sliding plate a now acts as a draw plate or
blower and quickly produces a more rapid combustion of the fuel in the fire grate.
When the sliding plate a is lowered into the position represented in Figure 4 and its
bottom edge rests on the hearth the said sliding plate completely covers the front of
the fire grate and the supply of air is practically cut off and by raising the sliding
plato a little above the position represented in Figure 4 a low or smouldering
combustion may be maintained in the grate. Thus the rate of combustion of the
fuel may be varied at pleasure by changing the position of the sliding plate or blower
as hereinbefore described.
In Figure 3 the sliding plate or blower is indicated in dotted lines in its fully
lowered position at a³.
Although in ordinary cases we make the sliding plate in one piece yet in some
cases we make it of two or more pieces sliding telescopically one behind the other.
In this arrangement the raised parts of the plate occupy less space than when the
plate is made in one piece.
Having now particularly described and ascertained the nature of our inven-
tion and the manner in which the same is to be performed we declare that we
claim as our invention :-
Regulating combustion in open fire places by means of a vertically sliding draw
plate or blower combined with the fire place and capable of descending in front
of and covering the bars of the grate and acting substantially as hereinbefore
described and illustrated in the accompanying Drawing.
Dated the First day of August 1889.
GEORGE GORDON BRODIE.
JAMES DAMREL PRIOR.