PROVEMENTS IN MACHINERY OR APPARATUS FOR THE PREVENTION OF SMOKE FROM FURNACES USED FOR STEAM BOILERS AND OTHER SIMILAR PURPOSES
Year: 1867

page_text: Sealed the 28th June 1867, and dated the 3rd January 1867.
PROVISIONAL SPECIFICATION left by the said Joseph Knowles Broadbent
at the Office of the Commissioners of Patents, with his Petition, on the
3rd January 1867.
1. JOSEPH KNOWLES BROADBENT, of the City of Manchester, in the County
of Lancaster, do hereby declare the nature of the said Invention for
PROVEMENTS IN MACHINERY OR APPARATUS FOR THE PREVENTION OF SMOKE FROM
FURNACES USED FOR STEAM BOILERS AND OTHER SIMILAR PURPOSES," to be as
follows:-
This apparatus consists of a self-opening and closing valve for regulating
the supply of air to the combustion chamber to suit the fluctuating conditions
of the fuel in the furnace, and thereby prevent the formation of smoke and
realize economy. Behind the ordinary bridge there is a second bridge. the
space between the two forming the combustion chamber. and in an aperture
in the front bridge below the fire-bars I place a valve having a shaft working
in bearings, and fix to the valve or shaft a lever jointed to a rod which extends
to the front of the furnace, and is attached to a long lever connected to a
mensuring apparatus or meter, which lever is moved one way by a projection
on the furnace door when the door is opened, and the other way by the
working of the meter. the mechanism of which is as follows:-The long lever
Price S1

page_text: is fixed to a shaft working in bearings in a box or frame. to which shaft is
fixed a ratchet or catch wheel. and on the shaft there is a spur wheel which
can turn loose on the shaft one way, but the other way turns with the shaft
by means of a spring catch in the teeth of the ratchet wheel.
The spur
wheel gears into a pinion which gives motion to a train of wheels terminating
with a crown wheel escapement and balance, and the long lever is also jointed
io a bell-crank lever having a weight which acts upon the mechanism and
moves the long lever forward at any desired speed according to the weight
and leverage. Behind the aperture in the bridge there is a perforated plate,
which is attached to the bridge by a hinge, and the air which passes through
the aperture, also passes through the perforations to the combustion chamber,
and this perforated plate may be turned up or opened for the purpose of
enabling the ashes or small coals that may have collected to be cleared away
through the aperture in the bridge. When the furnace door is opened the
long lever connected to the meter is forced back so as to pull the connecting
rod and turn the valve in the aperture in the bridge, so that it will be opened
to about one-third of its full extent, and the valve is in this position when the
furnace door is closed, but the meter is now at work and gradually moves the
lever inwards and causes the valve to turn by degrees so that it shall be full
open when the largest amount of air is required for combustion, and then
gradually closed as the amount of gases diminish, and when the door is opened
for another charge of fuel the lever is again forced back and the valve worked
as before.
I have only described one arrangement of the working parts of the meter,
but it is evident that the movements may be modified in various ways.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Joseph Knowles Broadbent in the Great Seal Patent Office
on the 2nd July 1867.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I. JOSEPH
KNOWLES BROADBENT, of the City of Manchester, in the County of Lancaster,
send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Third day of January, in the year of our Lord One
thousand eight hundred and sixty-seven, in the thirtieth year of Her reign.
did, for Herself. Her heirs and successors, give and grant unto me, the said
Joseph Knowles Broadbent, Her special license that I. the said Joseph

page_text: Knowles Broadbent, my 'executors, administrators, and assigns, or such others
as I. the said Joseph Knowles Broadbent, my 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 MACHINERY OR APPARATUS FOR THE PREVENTION OF SMOKE
FROM FURNACES USED FOR STEAM BOILERS AND OTHER SIMILAR PURPOSES," upon
the condition (amongst others) that I. the said Joseph Knowles Broadbent.
my executors or administrators, by an instrument in writing under my, 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 sanie
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.
NOW KNOW YE, that I. the said Joseph Knowles Broadbent, do hereby
declare 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 (that is to say):-
This Invention consists of a peculiar combination and arrangement. of
improved machinery or apparatus for admitting a constantly graduated supply
of atmospheric air to the flues of the furnaces of steam boilers. and other
similar furnaces in order to suit the varying requirements of the fuel and the
increasing and diminishing supply of the gases generated therefrom, and
limiting that supply to the smallest quantity required for the purpose of
perfect combustion, and thus prevent the formation of smoke and realize
economy in fuel. Behind the ordinary bridge there is a second bridge, the
space between the two forming the combustion chamber, and in the ordinary
bridge below the fire-bars I build or fix an air box having an aperture fitted
with a valve working on centres or pivots. To the valve is fixed an arm or
crank jointed to a rod which extends to the front of the boiler. and is jointed
at that end to a lever attached by a link to a lever connected with a meter for
iurning the valve in one direction, and on the furnace door there is an arm or
lever for acting on the levers, winding up the meter, and turning the valve in
the opposite direction. When the furnace is being closed the valve is turned
to the full extent in one direction, and is then open to about one-third of its
area, at the same time the meter commences to turn the valve in the opposite
direction, and when the valve has travelled about one-third of its course it
will be open to the full extent, when it will take about double the time to

page_text: travel the remaining portion of the distance towards closing, the time being
regulated by the action of the meter. Behind the air box or aperture in the
bridge there is jointed a perforated plate, and the air which passes through
the aperture also passes through the perforations in the plate to the com-
bustion chamber, and this perforated plate may be turned up and held in that
position by means of a quadrant or bent rod attached thereto, for the purpose
of enabling the ashes or small coals that may have collected behind the bridge
to be cleared away through the aperture.
These improvements will be clearly understood by the following particular
description thereof, reference being had to the figures and letters on the
accompanying two Sheets of Drawings, in which Fig. 1 is an end elevation.
Fig. 2 a longitudinal section, and Fig. 3 a sectional plan of part of a steam
boiler having my improved machinery or apparatus connected to it: Figs. 4.
5. and 6 are enlarged views of some of the parts: Figs. 7 and 8 are front
and side elevations of the meter drawn about full size: and Figs. 9 and 10
are front and top views of the same. Fig. 9 having a part of the outer casing
removed for the purpose of showing the interior.
In Figs. 1, 2, and 3, a represents the shell of the boiler; b. the flue: c, the
fire-bars; d. the furnace door: e, the ordinary bridge: f. the air box; g, the
valve, the outer box or case of the meter: and the perforated plate
behind the air box, and the parts marked f, g, and i are shewn enlarged in
Figs. 4. 5. and 6. The valve placed in the air box f turns on the pivots
and to the valve is fixed an arm 7 jointed to the rod m which extends to the
front of the furnace, and is attached at that end to the lever a, o. jointed to
the framing of the furnace door, the arm o being connected by the adjustable
link to the lever connected with the meter h. To the furnace door dis
jointed a weighted lever having its arm
door is opened for a fresh charge of fuel
the arm and then falls in front of it, so that when the door is being closed
the levers and rods shall be moved to the position shewn by the dotted lines,
and one motion given to the valve g in the air box and the meter wound up.
working in a staples, and when the
the arm 7 rides on the curved end of
The mechanism of the meter consists of a train of wheels and pinions
which are placed in a steam and dust tight cast-iron box h, and the velocities
of the movements are regulated by an escapement or fly wheel. The principal
shaft t, Figs. 9 and 10, is made long enough for one end to project through
the casing h, and is attached to the lever q. Figs. 7, 8, 9, and 10, by means of
a frictional socket u on the lever q, and the screw and nut which tightens
the sockets upon the shaft t to make the external connection, and at the same
time to preserve the interior from injury; or a wedge may be used instead of the

page_text: screw and nut. To the internal end of the shaft is attached a ratchet
wheel
wheel
which turns with the shait, and loose on the shaft there is a spur
gearing into a pinion y, there being a catch or click attached to the
spur wheel which allows the shaft and ratchet wheel to turn loose in one
direction, but holds them fast to turn the spur wheel in the other direction to
drive the other wheels of the train and regulate the time of closing the air
valve g. To the outside of the meter is attached a bell-crank lever a' carrying
a weight b', which lever is connected by a link c' and two screws to the lever q
connected by the short link p, Fig, 3, to the lever n, o, on the framing of the
door, and by moving the position of this link p the weight will be raised to a
greater or lesser extent by the action of the furnace door to
suit firing at long
being raised by
or short intervals, or quick or slow combustion, the weight
the closing of the furnace door for enabling it in its descent to work the meter
and the valve placed in the aperture in the bridge. The meter may be fixed
in any position, and either at the front or bridge end of the boiler, but
practically prefer to fix it on the outside of the boiler or furnace. The
perforated plate jointed behind the bridge for enabling the removal of the
ashes is shewn at i, Figs. 2, 3, 4, 5, and 6, and the quadrant or bent rod
at /', but it is obvious that this perforated plate may be placed in a slide and
raised by a lever if required. When the furnace door is opened to supply a
fresh charge of fuel the arm r is pushed aside, and then comes in front of the
arm of the lever n, o, jointed to the framing of the door, and is attached
to one end of the long connecting rod m connected to the valve in the air
box. As the door closes the arm turns the lever a, o, which pulls the con-
necting rod m and opens the valve q, and as the door is being closed the arm r
is again pushed back into its original position by a projecting piece or cam d',
Figs. 1 and 3, fixed to the framing of the furnace door. The meter and its
connections will now be disengaged from the arm on the furnace door and
regulate the descent of the weight and the motion of the valve, and when the
door is opened for another charge of fuel the lever is again forced back and
the valve worked as before.
The machinery or apparatus before described may be made of any suitable
dimensions, and the arrangement modified to suit the requirements, and
although I have only described one arrangement of the working parts of the
meter it is evident that the movements may be arranged various ways, and a
spring employed instead of a weight. The vacuum or draught guage marked g¹
on the front elevation of the boiler, Fig. 1, is for the purpose of indicating
when the bars are bare of fuel and the vacuum reduced by the superfluous
entry of air.

page_text: Having now described the nature of my said Invention, and the manner in
which the same is to be performed, I would have it understood that I do not
confine myself to the precise details of arrangement of parts; but what I
claim for the prevention of smoke and the economy of fuel is,-
First, the general arrangement, construction, and combination of the
machinery or apparatus to be attached to steam boilers or other furnaces.
Secondly, the application, use, arrangement, and combination of the meter
by which the main shaft is made to turn loose in one direction by the action
of the furnace door, and in the opposite direction by a weight acting upon a
lever, or by a spring coiled round the shaft driving a train of wheels and
pinions regulated by an escapement, fan, or fly wheel.
Thirdly, the application and use of the arm or lever on the furnace door by
which the meter is wound up and the valve opened.
Fourthly, the peculiar means of admitting and graduating the supply of air
to the combustion chamber or flues of steam boilers and other furnaces.
Fifthly, the frictional socket on the lever placed on the main shaft of the
meter, and the modes of tightening the socket in the shaft by means of a screw
and nut, or by a wedge.
Sixthly, the peculiar construction and method of attaching the perforated
plate to the air box or bridge for enabling it to be raised or turned up.
And, seventhly, the application and use of the quadrant or bent rod by
which the perforated plate is raised up, as all such improvements are herein
described and illustrated in the accompanying two Sheets of Drawings.
In witness whereof, the said Joseph Knowles Broadbent, have here-
unto set my hand and seal, this Twenty-seventh day of June, in the
year of our Lord One thousand eight hundred and sixty-seven.
JOSEPH KNOWLES BROADBENT. (L.S.)
Signed, sealed, and delivered by the
within-named Joseph Knowles
Broadbent, in the presence of
E. J. HUGHES,
Patent Agent,
Manchester.