IMPROVEMENTS IN STEAM . BOILER AND OTHER FURNACES, APPLICABLE IN PART TO GRATES OF VARIOUS KINDS."
Year: 1862

page_text: LETTERS PATENT to Joseph Sawyer, of Noble Street, in the County of
Middlesex, Engineer, and George Padgham, of Dalston, in the said County
of Middlesex, Gentleman, for the Invention of "IMPROVEMENTS IN STEAM
. BOILER AND OTHER FURNACES, APPLICABLE IN PART TO GRATES OF VARIOUS
KINDS."
PROVISIONAL SPECIFICATION left by the said Joseph Sawyer and
George Padgham at the Office of the Commissioners of Patents, with
their Petition, on the 14th June 1862.
We, JOSEPH SAWYER, of Noble Street, in the County of Middlesex, Engi-
neer, and GEORGE PADGHAM, of Dalston, in the said County of Middlesex,
Gentleman, do hereby declare the nature of the said Invention for "IM-
PROVEMENTS IN STEAM BOILER AND OTHER FURNACES, APPLICABLE IN PART TO GRATES
OF VARIOUS KINDS," to be as follows:-
This Invention consists in the use and adoption of fire-bars, which are
curved on the upper as well as the under surface, and at each side have pro-
jections, so that when one bar is put in pòsition by the side of another these
projections may fit closely against each other, leaving openings between them,
producing in effect a number of short air tubes or passages admitting. the air
to the fuel in the furnace to assist in the more effectual combustion of said
fuel. The projections, which are on each side of each bar, are so arranged that.

page_text: upon any bar being removed from its first position and its other side brought
into the position before occupied by the opposite side of the bar, the projec-
tions shall no longer correspond one to the other, but the projections of the
one shall be across the openings of the other, thus diminishing the area of
each opening or passage between the projections, and allowing smaller fuel to
be used, without diminishing the total extent of the areas, or the quantity of
air supplied to assist combustion. Instead of the top of the bar being convex
it may be flat; and instead of the usual bridge we have a furnace-plate placed
in a sloping direction, and construct the same hollow, that is, with a chamber
or air space at its back, and at the part below the level of the fire-bars, which
part has a valve that can be opened from the front of the boiler by a lever
handle, so as to admit the cool atmospheric air to the hollow, whence it passes
modified in temperature into the furnace, by reason that the said furnace-
plate is open at the top. Thus we are enabled to effect the more perfect con-
sumption of smoke. We also use a furnace door which is constructed with
two openings therein, which can be closed with slides; the upper one having a
hopper before it, so that fuel may be supplied to the furnace by moving the
upper slide to open the top opening. The hopper has its sides extended so as
to secure a false front to the same, and between this false front and the inner
front of the hopper there is an air space which descends and covers the lower
opening in the said furnace door, which opening can be used by removing a
slide provided opposite to it, covering an opening in the false front, so that the
rake may be inserted into the furnace. The bottom of this outer casing has
an opening to admit air so as to cool the front of the furnace door.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Joseph Sawyer and George Padgham in the Great Seal
Patent Office on the 13th December 1862.
"
TO ALL TO WHOM THESE. PRESENTS SHALL COME,..we, JOSEPH
SAWYER, of Noble Street, in the County of Middlesex, Engineer, and GEORGE
PADGHAM, of Dalston, in the County of Middlesex, Gentleman, send
greeting.
.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
.Patent, bearing date the Fourteenth day of June, in the year of our Lord
One thousand eight hundred and sixty-two, in the twenty-fifth year of Her

page_text: reign, did, for Herself, Her heirs and successors, give and grant unto us, the
said Joseph Sawyer and George Padgham, Her special licence, that we, the
said Joseph Sawyer and George Padgham, our executors, administrators, and
assigns, or such others as we, the said Joseph Sawyer and George Padgham, our
executors, administrators, and assigns, should at any time agree with, and no
others, from time to time and at all times thereafter during the term therein.
expressed, should and lawfully might make, use, exercise, and vend, within the
United Kingdom of Great Britain and Ireland, the Channel Islands, and Isle
of Man, an Invention for "IMPROVEMENTS IN STEAM BOILER AND OTHER FUR-
NACES APPLICABLE IN PART TO GRATES OF VARIOUS KINDS," upon the condition
(amongst others) that we, the said Joseph Sawyer and George Padgham,
our executors or administrators, by an instrument in writing under our,
or their, or one of their hands and seals, should particularly describe and
ascertain the nature of the said Invention, and in what manner the same
was to be performed, and cause the same to be filed in the Great Seal
Patent Office within six calendar months next and immediately after the
date of the said Letters Patent.
f
• NOW KNOW YE, that we, the said Joseph Sawyer and George
Padgham, do hereby declare the nature of the said Invention, and in what
manner the same is to be performed, to be particularly described and ascer-
tained in and by the following statement :-
The nature of the said Invention, as hath been heretofore set forth in and
by the Provisional Specification left and recorded upon the first application
for the said Letters Patent, we now, in compliance with the said condition in
the aforesaid Letters Patent contained declare to be as follows:-
This Invention, in the first place, consists in the use and adoption of fire-
bars, each of which are curved in the. upper as well as the under surfaco.
thereof, each of such bars having projections at each side, so that when one
bar is put in position by the side of another these projections may fit or nearly
fit against each other, leaving openings between them, producing in effect a
number of air tubes or passages admitting the air to the fuel in the furnace
to assist in the more effectual combustion of said fuel. The projections which
are on each side of each bar are so arranged that upon any bar being removed
from the first-mentioned position, and its other side brought; into the position
before occupied by the opposite side of the bar, the projections shall no longer
correspond one to the other, but the projections of the one bar shall be across
the opening of the other, thus diminishing the area of each opening or passage
between the projections, and allowing smaller fuel to be used, without dimi-
nishing the total extent of the areas or the quantity of air supplied to assist

page_text: combustion. Instead of the top of the bar being convex it may be flat
(though the convex-form we find the best). In the second place, instead
of the usual fire-bridge we have a furnace plate placed in a sloping direction,
and construct the same hollow, that is, with a chamber or air space at its
back; and at the part below the level of the fire-bars, which part (below the
fire-bars) has a valve, which may be opened (if thought desirable) from the
front of the boiler by a lever handle, so as to admit the cool atmospheric air to
the said air space, whence it passes modified in temperature into the furnace
by reason that the said furnace place is open at the top, and thus we are
enabled to effect the more perfect consumption of smoke. In the third place,
we also use a furnace door, which is constructed with two openings therein,
which can be closed with slides, the upper one having a hopper before it, so
that the fuel may be supplied to the furnace by moving the upper slide to
open the top opening. The hopper has its sides extended, so as to secure a
false front to the same; and between this false front and the inner front of
the hopper there is an air space, which descends and covers the lower opening
in the said furnace door, which opening can be used by removing a slide
provided opposite thereto, covering an opening through which the rake may be
inserted. The bottom of this outer casing has an opening to admit air, so
as to cool the front of the furnace. This Invention, though principally
intended for steam boiler furnaces, may be applied to other furnaces and grates
of various kinds.
Having thus described the nature of the said Invention, and incidentally
referred to the manner of performing the same, we will now, in further com-
pliance with the said condition of the said Letters Patent, proceed to fully
exemplify in what manner the same is to be performed by reference to the
accompanying Drawings, as follows:-
Fig. 1, longitudinal section of an ordinary cylindrical boiler with internal
"furnace; showing our improvements applied thereto; Fig. 2, detail plan view
of the furnace bars; Fig. 3, another detail plan view of the furnace bars.
In all the said Drawings A, A, denotes the boiler, in the internal cylinder
flue or tube whereof (the boiler represented being of the class known as the
Cornish boiler) is the furnace, composed, as shewn, of our improved bars B, B,
fitted to the usual "dead plate," or dead iron C, and to the usual transverse
supports or bearing bars D. At the back or inner end, of the furnace there
is fitted; in lieu of the ordinary bridge, a sloping furnace plate, of iron or
other suitable metal or material E, supported upon an upright plate F.. The
sloping plate E having two surfaces E and E*, that marked E being nearest
the back or end of the furnace, and the other, Ex, at the back of that marked

page_text: E, with an air space between, as shewn; this air space opening at the slit.x
to an air space between F and F* in the upright plate or part, the lower"
part of F having a valve opening with a flap or valve G loosely swung on two
pivots, and opening towards the front or or door of the furnace, to which valve
may be attached a rod or chain passing to the front of the furnace, the end'
of which may have a handle to enable the boiler attendant to open and shut
this valve at pleasure.. H is a flat partition plate, extending from E* to I,
which last is an upright plate, thus forming a smoke box H* to the furnace
plate. The top of the upright plate I* is sloped towards the plate F, as
shewn, with an opening i for the products of combustion to pass to the flue;
the surfaces of all these parts being equal to and filling the area (save as to
the extent of the openings before described) of the vertical section of the:
internal cylinder or flue. K, K, is the furnace door, which is made. (like
many furnace doors heretofore made) to slide in grooves L on the front or
end of the boiler, such door being opened and shut. by means of suspensory
chains passing over pulleys, one chain and pulley at each side of the door, as
hath been heretofore adopted. This furnace door is, as before mentioned,
provided with an upper opening M, and a lower opening N, which is shewn
in the Drawing as closed by the slides provided for that purpose; both these
openings M and N directly communicating with the furnace. O is a casing
attached to the outer surface of the said furnace door, and consists of a front
part and two sides of the form shewn, the upper or sloping part being the
hopper, which hopper has both a front and a false or inner front O*, the
space between 0 and Ox admitting the air; this space opening at bottom to
the interior K of the lower part of the aforesaid casing where the aforesaid
lower opening N is situate. K' is a slide with a handle at top, this slide
covering the upper opening M, the opening N being covered by two slides
which meet together. O' is a slide for shutting the bottom of the said door
casing O, and O2 is a lid to the hopper. When this Invention is to be applied
to ovens, such as bakers' ovens, for instance, we should insert the bridge plate
at the back of the fire-place as near the fire-bars as possible, just at the
entrance into the oven at the fire-way; the ordinary door could, however, be
adopted. In grates of other kinds the bars alone might be useful. It is
evident that the door may be used alone, the bars alone, and the plate bridge
alone with some benefit; but to get the full benefit of the Invention the
whole must be adopted. In the construction of the various parts, unless
otherwise herein described, we prefer to employ such materials as are usually
adopted by engineers and mechanists in the construction of furnaces and
boilers.

page_text: Having now particularly described and ascertained the nature of the said
Invention, and in what manner the same is to be performed, we hereby
declare that we do not claim any of the parts described and shewn by the
Drawings in severalty; what we claim being the construction of the aforesaid
bars, the before described furnace plate in lieu of the usual fire-bridge, and
the before described fire-door arrangements.
In witness whereof we, the said Joseph Sawyer and George Padgham,
have hereunto set our hands and seals, this Thirteenth day of December,
in the year of our Lord One thousand eight hundred and sixty-two.
JOSEPH SAWYER. (L.S.)
GEORGE PADGHAM. (L.S.)
Witness,
B. WALKER,
Clerk to General Patent Co., Lima.
71, Fleet Street.