IMPROVEMENTS IN STEAM BOILER ANDOTHER FURNACes, and ApparATUS CONNECTED THEREWITH
Year: 1873

page_text: LETTERS PATENT to Charles Gall, of Halifax, in the County of York,
Engineer, for the Invention of "IMPROVEMENTS IN STEAM BOILER AND
OTHER FURNACes, and ApparATUS CONNECTED THEREWITH,'
"

page_text: the atmospheric supply by the closing of the furnace door as the fire
becomes bright.
Secondly. The construction of grate bars in such manner as that the
same are preserved from the destructive action of the fire, also that bars
so constructed contribute to the more entire combustion of fuel, and
assist in the combustion or condensation of the smoke arising from such
furnaces.
The mechanism for ensuring a decreasing supply of air to the
furnaces is similar to that described in the Specification of Letters
Patent granted to George Douglas Hughes, A.D., 1867, No. 3314; 1
and consist of a horizontal shaft supported in bearings above the
furnace door, to which shaft, by means of worms and worm wheels
and other gear wheels, a slow rotation is imparted. A loose boss
on the shaft carries two arms, on one of which are palls or catches
working in a catch wheel on the said shaft, and to this arm is applied
a counterbalance weight (for purpose herein-after described); to tho
end of the second arm is attached one end of a connecting rod, the
other or lower end of which rod is secured to a forked lever, the latter
working on a stud fixed over the fire-door. The upper fork of the lever
is clongated and curved so as to form an incline, against which a
projecting pin attached to the furnace door comes in contact with and
so insures tho pin entering between the prongs of the fork lever when
the furnace door is partially closed after "firing."
"
The operating of the apparatus is as follows:-On the furnace door
being opened the pin attached thereto will act on the forked lever,
whereby the connecting rod and the arms attached to the loose boss
on the shaft first herein referred to will tilt on their boss or shaft
and so the door will be opened. Meanwhile the catches on the balance
arm of the lever have engaged with the teeth of the catch wheel,
and the connecting rod and forked lever are held in a raised position.
On the door being partially closed the pin thercon coming in contact
with the incline is thereby directed to the entrance of or between the
prongs of the forked lever. The rotation of the shaft and the greater
weight of the connecting rod through the forked lever acting on the
pin attached to the door closes the same, and so the decreasing supply
of air to the furnace is ensured independently of the attention of the
stoker or attendant. It will thus be seen that tho stoker cannot

page_text: entirely close the door after firing, and that when a suitable time
has elapsed the door will be closed irrespective of attention on his
part. A plate is attached to the inside of the door for the purpose of
directing the current of air upon or over the fire.
The grate bars I construct cach with a hollow rib which serves
as a water space or chamber, the communication between the bars
where more than one bar in continuation is employed, is effected by
means of short length of pipe protruding therefrom, which in turn
are connected by india-rubber or flexible tubes in order to admit of the
contraction and expansion of the bars. Under or near the dead plate
I place a water-tight case or vessel connected by pipes with the hollow
grate bars, and these as described above communicate with each other
by means of other pipes and flexible tubes. The upper portion of the
water chambers formed in the ribs of the bars are perforated or pierced
with holes through which steam is discharged, which passes upwards
to tlic fire, and assists in the consumption or condensation of the smoke
arising from the fuel, and for the preservation of the grate bars.
In some cases I employ an air-tight compartment placed near to
and extending under the dead plate, from which pipes (having flexible
connections) extend under the grate bars communicating with the
cavity ends of the grate bars nearest the bridge, an air is forced
through and along these pipes by means of a fan, and through the
hollows, perforations, and connecting pipes of the grate bars again
to the front of the boiler, where the various pipes are connected with
a pipe which conducts and discharges the air so heated to the front of
the furnace.
The top or fuel surface of the bars is formed by a central rib from
which others of suitable dimensions extend at right angles.
When the fan and pipes are employed for the purpose of forcing air
through the bars, the mechanism for closing the furnace door is not
required to be used.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Charles Gall in the Great Seal Patent Office on
the 1st August 1873.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, CíARLES
GALL, of Halifax, in the County of York, Engineer, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the First day of February, in the year
of our Lord One thousand eight hundred and seventy-three, in the
thirty-sixth year of Her reign, did, for Herself, Her heirs and suc-
cessors, give and grant unto me, the said Charles Gall, Her special
licence that I, the said Charles Gall, my executors, administrators, and
assigns, or such others, as I, the said Charles Gall, my executors, ad-
ministrators, and assigns, should in 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 Iroland, the Channel
Islands, and Isle of Man, an Invention for "IMPROVEMENTS IN STEAM
BOILER AND OTHER FURNACES, AND APPARATUS CONNECTED THEREWITH," upon tho
condition (amongst others) that I, the said Charles Gall, my executors
or administrators, by an instrument in writing, under my, or their, or
one of their hands and scals, 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 dato
of the said Letters Patent.
NOW KNOW YE, that I, the said Charles Gall, do hereby declaro
the nature of my said Invention, and in what manner the same is to be
performed, to be particularly described and ascertained in and by the
following statement and accompanying Sheets of Drawings, that is to
say:―
The objects of this Invention arc,-
Firstly. The construction, application, and use of mechanism for the
purpose of ensuring a supply of air to the furnaces of steam boilers
when fuel is applied, and the self-acting withdrawal or shutting off
the atmospheric sunnly by the closing of the furnace door as the five

page_text: Secondly. The construction of grate bars in such manner as that the
same are preserved from the destructive action of the fire, also that bars
so constructed contribute to the more entire combustion of fuel, and
assist in the combustion or condensation of the smoke arising from such
Lurnaces.
The mechanism for ensuring a decreasing supply of air to the
furnaces is similar to that described in the Specification of Letters
Patent granted to George Douglas Hughes, A.D., 1867, No. 3314;
and consists of a horizontal shaft supported in bearings above the
furnace door, to which shaft, by means of worms and worm wheels
and other gear wheels, a slow rotation is imparted. A loose boss
on the shaft carries two arms, on one of which are pawls or catches
working in a catch wheel on the said shaft, and to this arm is applied
a counterbalance weight (for purpose herein-after described); to the
end of the second arm is attached one ond of a connecting rod, the
other or lower end of which rod is secured to a forked lever, the latter
working on a stud fixed over the fire-door. The upper fork of the lever
is elongated and curved so as to form an incline against which a
projecting pin attached to the furnace door comes in contact with and
so ensures the pin entering between the prongs of the fork lever when
the furnace door is partially closed after firing."
The operating of the apparatus is as follows:-On the furnace door
being opened the pin attached thereto will act on the forked lever,
whereby the connecting rod and the arms attached to the loose boss
on the shaft first herein referred to will tilt on their boss or shaft
and so the door will be opened. Meanwhile the catches on the balanco
arm of the lever have engaged with the teeth of the catch wheel,
and the connecting rod and forked lever are held in a raised position.
On the door being partially closed the pin thereon coming in contact
with the incline is thereby directed to the entrance of or between the
prongs of the forked lever. The rotation of the shaft and the greater
weight of the connecting rod through the forked lever acting on the
pin attached to the door closes the same, and so the decreasing supply
of air to the furnace is ensured independently of the attention of the
stoker or attendant. It will thus be seen that the stoker cannot
entirely close the door after firing, and that when a suitable time
has clapsed the door will be closed irrespective of attention on his

page_text: part. A plate is attached to the inside of the door for the purpose of
directing the current of air upon or over the fire.
The grate bars I construct each with a hollow rib which serves
as a water spaco or chamber; the communication between the bars,
where more than one bar in continuation is employed, is effected by
means of short lengths of pipe protruding therefrom, which in turn
are connected by indin-rubber or flexible tubes in order to admit of the
contraction and expansion of the bars. Near the dead plate I place
a water-tight case or vessel connected by pipes with the hollow grate
bars, and these as described above communicate with each other by
means of other pipes and flexible tubes. The upper portions of the
water chambers formed in the ribs of the bars are perforated or pierced
with holes through which steam is discharged which passes upwards
to the fire, and assists in the consumption or condensation of the smoke
arising from the fuel, and for the preservation of the grate bars.
The top or fuel surface of the bars is formed by a central rib, from
which others of suitable dimensions extend at right angles.
When the fan and pipes are employed for the purpose of forcing air
through the bars, the mechanism for closing the furnace door is not
realised to his used

page_text: the end of the second arm is attached one end of a connecting rod J,
the other or lower end of which rod is secured to a forked lever J',
the latter working on a stud Js fixed over the fire-door or other
convenient part. The fork of the lever is elongated and curved so
as to form an incline K, against which a projecting pin L attached
to the furnace door comes in contact with and so ensures the said
pin entering between the prongs of the fork lever (sec Fig. 3) when
the furnace door is partially closed after "firing." On the furnace door.
being opened the pin. L attached thereto will act on the forked lever J',
whereby the connecting rod J and the arms attached to the loose boss
on the shaft A will tilt on the said shaft and so the door will be
opened. Meanwhile the catches G on the balance arm of the lever
have engaged with the teeth of the catch wheel H, and the connecting
rod J and forked lever J' are held in a raised position. On the door
being partially closed the pin L thereon coming in contact with the
incline K is thereby directed to the entrance of or between the prongs
of the said forked lever. The rotation of the shaft A and the greater
weight of the connecting rod J through the forked lever acting on the
pin Lattached to the door closes the same, and so the decreasing
supply of air to the furnace is ensured independently of the attention
of the stoker or attendant. At M is shewn a slot in the connecting
rod J and the handle or lever of a steam tap M', so that this self-acting
apparatus may open and close the said tap for the supply of steam
to the furnace as required. N is a grate bar having a hollow rib N'
which serves as a water space or chamber, the communication between
the bars, where more than one bar in continuation is employed, is
effected by means of short length of pipe protruding therefrom, which
in turn are connected by india-rubber or flexible tubes N* in order
to admit of the contraction and expansion of the bars. Near the
dead plate I place a water-tight case or vessel P connected by pipes P¹
with the cavity N₁ of the said bars. An uniform supply of water to
the cavity of the grate bars is secured by the use of the float R, which
acts on the arms S, S, which raise the valve and rod T as water is
required to be admitted or excluded from any source of supply by
way of the pipe W. The upper portion of the water chambers formed
in the ribs of the bars are perforated or pierced with holes W¹ through
which steam is discharged which passes upwards to the fire, and assists
in the consumption and condensation of the smoke arising from the fuel,
and for the preservation of the grate bars.

page_text: In some cases I employ in lieu of water air which by means of
a fan Z is forced through the pipes P', and cavity N', and per-
forations W
The top or fuel surface of the bars is formed by a central rib from
which others of similar dimensions extend at an angle.
When the fan Z and pipes Z' are employed for the purpose of forcing
air through the pipes 1" and cavity N₁ of the bars, the mechanism for
closing the furnace door is not required to be used.
In witness whereof, I, the said Charles Gall, havo hereunto set my
hand and scal, this Thirtieth day of July, in the year of our Lord
One thousand eight hundred and seventy-three.
Witness,
WALTER BRIERLEY,
Tasker & Brierley,
Halifax & Bradford.
CHARLES GALL. (L.S.)