Improvements in and relating to Fire Grates or Stoves.
Year: 1899

page_text: Date of Applicatión, 14th July, 1899-Accepted, 2nd Sept., 1899
COMPLETE SPECIFICATION.
Improvements in and relating to Fire Grates or Stoves.
I, ALEXANDER CRAIG MATHER, of No. 23, Havelock Street, Dowanhill, Glasgow,
in the County of Lanark, Mechanical 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:-
This invention relates to improvements in domestic fire grates or stoves and has
for its object the construction of a fire grate in which the heat produced by com-
bustion of the fuel is utilized much more efficiently than in those at present
constructed.
In carrying out this invention I apply to the shell of an ordinary domestic
fire grate, a casing, in such a manner that an air space or chamber may surround
the fire box of the improved grate, except at the front fire bars, the air space
or chamber communicating through openings with the room in which the fire
grate is located, these openings are preferably the full height of the air chamber
and may be controlled by shutters or doors.
The back of the fire box being enclosed by an air chamber and becoming
heated by the action of the fire induces a continuous current of air to enter
the lower portion of openings, and becoming expanded by heating while passing
up round the chamber is emitted into the room, thus the air of the room may
continue to circulate and be heated.
The air chamber may preferably be placed at the back of the fire grate shell
in grates that are being constructed or to be constructed.
In fire grates already made or at present in use the air chamber may preferably
be placed at the front of the fire grate shell and so modified as to suit the fire
box.
Additional openings may be placed under the fire box for the entry of air
should increased flow be desired.
In the improved fire grate the fire box may have grooves or projections or
be otherwise constructed so as to readily absorb and radiate the heat.
In the accompanying sheet of drawings.
Figure 1 is a front elevation of a fire grate constructed according to this
invention adapted for large or small rooms.
Figure 2 is a vertical section at the line 2-2 of Figure 1.
Figure 3 is a horizontal section at the line 3-3 of Figure 1.
Figure 4 is a modification of Figure 2.
Figure 5 is a modification of Figure 3.
In Figures 2, 3, 4, and 5, the fire box A together with shell B
may
be
an ordinary domestic fire grate or stove.
In Figures 2 and 3, C is an outer casing to shell B forming an air chamber D
and communicating with the room through openings E.
In Figures 4 and 5, C is an inner casing to shell B forming an air chamber ])
and communicating with the room through openings E.
Casing C is prolonged downwards as at U in Figures 2 and 4.
In Figures 4 and 5 casing C is set within fire box A having the sides formed

page_text: as at Fin Figures 1 and 4 so that the front fire bars a of the fire box A may
be unshipped and shipped as desired.
In Figures 4 and 5 the portion T stopped off the bottom of fire box A by
casing C, may form the lower part of air chamber D, the air chamber may not
communicate with the ashes place.
In Figure 2 openings O may be made in shell B under fire box A giving largely
increased area.
It is evident that openings for the entry of air might be placed at the back
of fire grate and so arranged as to draw a supply of fresh pure air from the
outside of the building or they might be placed both ways at the back and at
the front and in that case might be provided with shutters.
In Figures 2, 3, 4, and 5, the improved fire grate may have the fire box
formed with grooves or projections P, giving greatly increased surface.
When in operation the air entering through lower portion of openings E pass
up round the heated back of fire box, returning to the room through upper
portion of openings.
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:-
First. In a fire grate or stove an air heating chamber inclosing the fire box
for inducing a continuous current and distributing the heated air, substantially
as herein described.
Second. The combination of a fire box and shell with an outer casing, sub-
stantially as herein described or illustrated.
Third. The combination of a fire box and shell with an inner casing, sub-
stantially as herein described or illustrated.
1000