IMPROVEMENTS IN STEAM BOILER AND OTHER FURNACES
Year: 1873

page_text: LETTERS PATENT to Henry Clifton Carver, of Birkenhead, in the
County of Chester, Engineer, for the Invention of "IMPROVEMENTS
IN STEAM BOILER AND OTHER FURNACES.”
Sealed the 20th January 1874, and dated the 14th August 1873.
PROVISIONAL SPECIFICATION left by the said Henry Clifton Carver
at the Office of the Commissioners of Patents, with his Petition,
on the 14th August 1878.
I, HENRY OLIFTON CARVER, of Birkenhead, in the County of Chester,
Engineer, do hereby declare the nature of the said Invention for
“IMPROVEMENTS IN STEAM BOILER AND OTHER FURNACES," to be as follows:-
My Invention consists in an improved combination and arrange-
ment or fire-bars to be used for breaking up the superimposed fuel and
clinker for the admission of air, and also for discharging clinker from
the bars.
The arrangement and combination consists of a series of fire-bars
placed longitudinally in the furnace which are alternately fixed and

page_text: moveable bars. When in their normal position both the fixed and
moveable bars rest upon two cross bearers. The moveable bars have
upon their under sides, where they rest upon the cross bearers inclines
which, when end motion is imparted, will cause them to rise to the.
normal level of the bars. Motion is imparted to the moveable bars by
means of two cross cradles or rocking beams toothed on their under
surface at each end to rest upon toothed brackets secured to the sides of
the furnace, and motion is conveyed from one cross cradle to the other
by forming one of the moveable bars so as to act as a connection between
the two cross cradles. The moveable bars are provided with steps or :
projections underneath, which rest and bear upon the cradles, when
motion is to be imparted to them. When it is desired to break up the
clinker and fuel for the admission of air, the highest part of the steps
on the moveable bars rests upon the cross cradles, and when it is desired
to discharge clinkers from the furnace the lowest part of the steps on
the moveable bars rests upon the cross cradles and are lifted above the
normal level of the bars. In both these cases the moveable bars are
carried endways in one direction by one of the cross cradles pressing
against projections underneath them, and in the other direction by one
of the cross cradles pressing against the ends of the bars. The fixed
bars are prevented from being lifted at one end by the fire-bridge or
"dead plate," and at the other end by catching into the bearer at
that end.
When the clinker and ashes are to be discharged at the front of the
furnace the dead plate is made to lift up either by independent
mechanism or by being connected with the rocking gear of the cross
cradles.
When the clinker and ashes are to be delivered at the back of the
furnace the bridge plate must be sufficiently elevated, or there must be
an arch or space formed above the bars to allow a passage between it
and the bars and to receive the clinkers and ashes discharged.
The cradles may be rocked or worked intermittently either by hand
or by power, and in conjunction with mechanical fuel feeders if
desired.
•

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Henry Clifton Carver in the Great Seal Patent
Office on the 18th February 1874.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, HENRY
CLIFTON CARVER, of Birkenhead, in the County of Chester, Engineer,
send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Fourteenth day of August, in the year
of our Lord One thousand eight hundred and seventy-three, in the thirty-
seventh year of Her reign,,did, for Herself, Her heirs and successors, give
and grant unto me, the said Henry Clifton Carver, Her special license.
that I, the said Henry Clifton Carver, my executors, administrators,
and assigns, or such others as I, the said Henry Clifton Carver,
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 STEAM BOILER AND OTHER FURNACES," upon the condition
(amongst others) that I, the said Henry Clifton Carver, by an instru-
ment in writing under my hand and seal, 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 imme-
diately after the date of the said Letters Patent.
NOW KNOW YE, that I, the said Henry Clifton Carver, 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 and the accomapanying Drawings (that
is to say) :-
My Invention consists in an improved combination and arrange-
ment of fire-bars to be used in breaking up the superimposed clinker
for admission of air, and also for discharging clinker from the bars, and
will be explained by reference to the accompanying Drawings described
as follows:-
Figs. 1, 2, and 3, represent the bars arranged either for cleaning off
at the back end of or use as ordinary rocking bars and to be worked by
hand, in Fig. 1 a longitudinal section, and Fig. 2 a cross section,

page_text: A. is a moveable bar which is sometimes supported on the cross cradles
B, B', and sometimes on the cross bearers C, C'. a, a', are steps
with inclined sides; b is an incline, and c is a supporting point (which
may sometimes be omitted) all on the under side of the bar; d is a
thrust abutment, and e a lift abutment both at the back end of the
bar. The cradles B, B¹, are toothed at each end on the under side and
rest on toothed boxes or brackets D, D', which may be made cither
for building into the walls of furnaces as shewn, or for attaching to the
flues of internally fired boilers. The teeth on the cradles and boxes or
brackets may be disposed either curvilinearly or rectilinearly, and those
on the boxes or brackets may be placed either horizontally or on an
incline, the cradles are provided with spaces or holes k, k, which prevent
the accumulation of cinder and other matters upon them; they are also
connected together by means of the arms o, o, and the rod E as shewn.
The cross bearers C, C¹, also rest upon the boxes or brackets D, D¹, and
the ends of the bearer C¹, are rounded on the under side, and the recesses
in which it rests are rounded to correspond. This bearer is also pro-
vided with the latch or projection / at one side of it. F is the dead
plate at the front end of the furnace which may in some cases be pro-
vided with the projection 9 extending for its whole length, and also with
the lugs fabout which it may hinge slightly; G is an overhanging fire-
bridge which extends over the back ends of the bars and at an elevation
above them, so as to form a tunnel or chamber H; J is the end wall of
the ash-pit built at some distance from the ends of the bars; and K is a
moveable damper or door placed across the ash-pit so as to shut off the
space or chamber L.
The shaft N, arms, o, o¹, and moveable handle P,
show how the bars may be actuated by hand.
Fig. 3 is a longitudinal section shewing the arrangement of the fixed
bars. M is a fixed bar supported on the bearers C, C', and shaped
at one end to fit over the latch h of the bearer C¹, and is thus pre-
vented from being lifted off the bearer. In placing the fixed bars on
the bearer C¹, the latch must be turned slightly upwards till all the bars
are in the furnace, and then turned down into the position as shown.
The fixed and moveable bars are placed in the furnace alternately side
by side, or two or more of one or both kinds may be placed together.
To work the bars for cleaning the furnace the handle P is to be moved
up and down so as to cause the moveable bars to fall at about the top of
the up-stroke and so as to bring the cradles and bars into the position

page_text: .
shewn in Fig. 1, at the end of the down stroke, when the upper surfaces
of both the fixed and moveable bars will be on the same horizontal level.
The action of the bars when an oscillating motion is communicated to
the cradles B, B', through the rod E and cranks O, O', by the up-
and-down working of the handle P is as follows:-The portion / of
the cradle B lifts the front ends of the moveable bars by coming in
contact with the steps a of the bars, and the portion m of the cradle B¹
lifts the back ends of the bars by coming in contact with the steps a³,
and at the same time thrusts the bars backwards by coming in contact
with the abutments & of the bars. It will be seen that in the mean-
time the portion n of the cradle B³, will have receded from the ends of
the bars. This operation will have lifted the load off the fixed bars and
have carried it backwards on the moveable bars when, or shortly before
or shortly after (as the case may be), the motion of the handle P and
3 consequently that of the cradles B, B¹, is reversed the moveable bars
will fall below the level of the fixed bars and leave the load supported
on the latter only. As the reverse motion continues the portion of
the cradle B¹, comes in contact with the ends of the moveable bars,
and with their abutments e pushes them forwards, and lifts or causes
O them to be lifted to the normal level by the lifting action caused by the
motion of the cradle B³, in contact with the abutments e and by the
sliding of the inclines b on the bearer C. This reverse motion will have
caused that part of the load which (in the backward motion of the
moveable bars) had been carried beyond the ends of the fixed bars to
5 be discharged into the space or chamber L. The falling of the
moveable bars may be caused either by adjusting the cradles B, B¹, so
that the steps a, whose sides are inclined as shewn, are either just before
or at the end of the up stroke drawn clear of the portion of the cradle
B, which action will cause the front ends of the bars to slide down the
0 inclined-sides of the steps a in contact with the portion of the bearer B,
and in-doing-so will cause the steps a³, to slide off the portion m of
the cradle B³, and so allow the back ends of the bars to fall. Or the
moveable bars may be caused to fall by means of the projection g on the
under side of the dead plate F as follows:-In moving backwards and
5 upwards the bars come in contact with the projection g and cause the
dead plate to lift slightly and to move on the hinge f; by the time the
up stroke of handle P is completed the ends of the bars will have been
drawn clear of the projection g, and the dead plate will have fallen so
as to oppose the return of the bars until in the course of the down

page_text: stroke of the handle P the portions l, m, of the cradles B, B¹, have
been drawn clear of the steps a, a', when the ends of the bars will fall
below the projection 9, and thus have their further return unimpeded.
An independent fall plate may be used to answer the purpose just
described. The overhanging bridge G prevents the addition of fresh
fuel beneath it, and consequently when the bars are being worked con-
tinuously enables combustion of the fuel to take place before the
residues are discharged into the space or chamber L. At intervals
the discharged residues are withdrawn by opening the damper or door
K which prevents unnecessary cold air rushing rounds the ends of the
bars into the furnace. The bridge G also serves as a conservator of
heat, and facilitates combustion in a manner which will be well under-
stood. To work the bars merely for the purpose of breaking up the
fuel and clinker, the handle P is to be worked up and down as already
described, but the up-stroke must either not be continued so far as to 1
cause the falling of the moveable bars, or having been continued so far
then the down-stroke must not be continued so far as to bring the portions
l, m, of the cradles B, B', immediately under the steps a, a¹. The tops
of all the bars may be corrugated, if desired, for the more efficacious
breaking up of the fuel and clinker or discharge of the residues.
I have now particularly described the nature of my Invention and
the mode of carrying the same into effect, and claim as my Invention,―
Firstly. The combination and arrangement of fire-bars for furnaces
where movement is given by rockers, substantially as herein-before
described and illustrated by the accompanying Drawings.
Secondly. The overhanging fire-bridge substantially as described,
when used in combination with ash and clinker discharging fire-bars.
In witness whereof, I, the said Henry Clifton Carver, have here-
unto set my hand and seal, this Twelfth day of February, in
the year of our Lord One thousand eight hundred and seventy- g
four.