Improvements in Mechanical Stokers and Cinder-breakers for Furnace Grates.
Year: 1899

page_text: PROVISIONAU SPECIFICATION.
Improvements in Mechanical Stokers and Cinder-breakers for
Furnace Grates.
I, JOSEF KUDLICZ, of Bubna, near Prague, Bohemia, in the Empire of Austria,
Manufacturer, do hereby declare the nature of this invention to be as follows:-
This invention relates to mechanical stokers of the kind described in my former
Patent No. 2298 dated January 28th 1898, and in which comb-shaped stokers,
arranged below the grate, are combined with operating mechanism for raising
the said stokers with their teeth or blades passing through the interstices between
the fire-bars and penetrating into the fuel, moving them forward, towards the
fire bridge, in order to push the fuel upon the grate in the same direction and to
clear the interstices between the fire-bars of cinders, and finally lowering them
below the grate and returning them into their rearmost or initial position.
Now this invention has for its object to provide simple and effective mechanism
for operating the stokers by hand, and to so construct the grate that it is less
liable to become distorted by unequal heating of its parts.
According to the invention a stoker in the shape of a two-armed lever is
arranged below the grate in such a manner that its fulcrum can be moved to and
fro the whole length of the grate and to the right and left for the breadth of the
grate; the front end of the said two-armed lever carrying a stoking blade or a
comb-shaped stoking device, while its rear end projects from the ash-pit to the
outside and is provided with a suitable handle. The movable fulcrum is by pre-
ference formed of two slides, for which guide ways are formed in the sides of
the ash-pit and of a rod connecting the said slides and forming the pivot of the
stoking lever, which is also adapted to slide along the said rod.
When the said stoker is at rest, it is in its rearmost position with its stoking
blade or blades raised so that they pass through an interstice or through inter-
stices between the grate bars into the heap of coal constantly kept upon the rear
end of the grate, when the handle of the stoker is lowered. For stoking at any
point of the grate and feeding fuel thereto, the operator first raises the handle
thereby lowering the stoking blade or blades below the grate and afterwards shifts
the stoking lever sidewise so as to bring the stoking blade or blades below the
interstices to be cleaned. Then he lowers the handle so as to cause the blade
or blades to penetrate into the coal to the required extent, and pushes the stoker
forward. As soon as the toothed front end of the stoker has reached the end of
the grate near the fire bridge, the handle is again raised and the stoker, with
its teeth or blades lowered below the grate, is withdrawn into its original posi-
tion, when the handle may be allowed to drop down or the stoking operation may
be repeated.
In some cases I replace the slides by small carriages mounted on rollers and I
form in the sides of the ash-pit two superposed guide-ways the ends of which are
in connection and provided with suitable gravitating switches. With this arrange-
ment, the operator only needs to push the stoking lever forward and draw it back-

page_text: ward, as, owing to the automatic operation of the switches, the carriage always
advance along the upper guideways and return along the lower ones.
In a modification of the stoking lever above described, the stoking teeth are
made movable round horizontal pivots and are connected by a rod to a spring
lever pivoted to the rear end of the stoker, whereby the operator is enabled to
fold the blade or blades down before withdrawing the stoker.
In another modification the bearings by means of which the stoking lever is
movably connected with the cross har between the two slides, is replaced by a
small grooved pulley secured to the lever and resting upon the cylindric cross bar.
The grate is constructed of a number of separate lengths each consisting of a
rectangular frame surrounding a number of fire-bars cast in one piece with the
said frame. These separate lengths of grate are slid into grooves formed in the
sides of the furnace chamber or firebox, and can easily be replaced when neces
sary. The stokers used with such transversely divided grates are provided with
stoking blades having a yielding spring connection with their carrier.
Dated this 9th day of January 1899.
G. F. REDFERN & Co..
4, South Street, Finsbury, London, Agents for the Applicant.
Improvements in Mechanical Stokers and Cinder-breakers for
Furnace Grates.
I, JOSEF KUDLICZ, of Bubna, near Prague, Bohemia, in the Empire of Austria,
Manufacturer 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 mechanical stokers of the kind described in my former
Patent No. 2298 dated January 28th 1898, and in which comb-shaped stokers,
arranged below the grate, are combined with operating mechanism for raising
the said stokers with their teeth or blades passing through the interstices between
the fire-bars and penetrating into the fuel, moving them forward, towards the
fire bridge in order to push the fuel upon the grate in the same direction and to
clear the interstices between the fire-bars of cinders, and finally lowering them
below the grate and returning them into their rearmost or initial position.
Now this invention has for its object to provide simple and effective mechanism
for operating the stokers by hand, and to so construct the grate that it is less
liable to become distorted by unequal heating of its parts.
According to the invention, a stoker in the shape of a two-armed lover, which
may be made frame-shaped, is arranged below the grate in such a manner that its
fulcrum can be moved to and fro the whole length of the grate and to the right
and left the breadth of the grate; the front end of the said two-armed lever carry-
ing a stoking blade or a comb-shaped stoking device, while its rear end projects
from the ashpit to the outside and is provided with a suitable handle.
For preventing the grate from becoming distorted it is constructed of a number
of separate lengths, each consisting of a rectangular frame surrounding a number
of fire-bars cast in one piece with the said frame. The stokers used with such
transversely divided grates are provided with stoking blades having a yielding
spring connection with their carrier.
It is obvious that the mechanical stoker constructed according to my invention
can also be used in combination with grates having hollow fire-bars cooled by

page_text: air. In this case, the heated air having passed through hollow fire-bars, is
utilized for supporting the combustion and the ash-pit is normally kept closed in
order to avoid the introduction of surplus air.
To enable my invention to be fully understood I will describe how it can be
carried into practice by reference to the accompanying drawings, in which:-
Figure 1 is a sectional side elevation of the furnace of a Cornish boiler pro-
vided with my improved stoker:
Figure 2 is at the left-hand side a cross section and at the right hand side an
end elevation of the said furnace and stoker:
Figure 3 is a front elevation and top view of a rod round which the stoking
lever can be swung and along which it can slide, the said rod having its ends
secured to carriages mounted on rollers, for which guide ways are formed in the
sides of the ash-pit:
Figures 4 and 5 are an underside view and a sectional side elevation, respec-
tively, of a stoking lever provided with a folding stoking blade:
Figure 6 is a side elevation partly in section, an end elevation, and a top view
of a stoking lever having its fulcrum formed by a grooved pulley resting on the
cross-rod, which connects the two slides or carriages:
Figure 7 is an elevation of two superposed guide-ways, formed in the sides of the
ash-pit, the upper guideway being connected with the lower one by inclines at
both ends and a gravitating switch being pivoted to the rear end junction:
Figures 1 and 2 are a sectional side elevation and a sectional end elevation,
respectively, of a boiler furnace provided with my improved mechanical stoker,
and having its grate composed of a number of separate lengths:
Figure 3 is a front and a side elevation of a stoking comb, the blades of which
consist of two separate lengths, connected by flat springs rivetted thereto, the
lower lengths being inserted in a cast iron carrier:
Figure 4 shows similar views of a stoking comb, the blades of which are
inserted in a tubular carrier or back :
Figures 8, 9 and 10 are a sectional side elevation, a sectional plan and a rear
elevation partly in section, respectively of a furnace, provided with my improved
mechanical stoker, and having tubular grate-bars cooled by the air which flows
through them, the heated air being caused to flow out below the grate.
Figure 11 is a detached plan and section of the carriage upon which the stoking
lever is fulcrummed.
It will be seen by reference to Figures 1 and 2 that T-iron bars A are arranged
below the lateral edges of the grate and that slides B, adapted to be moved along
the said T-iron bars, are mounted on the latter. The slides B, which may be
provided with antifriction rollers, are connected with each other by one or more
transverse rods C, having their ends loosely inserted in the said slides, in order
to provide for the dilatation of the rods under the action of radiating heat.
Upon the rod Crests the stoking lever D, to the front end of which are secured
two stoking blades E for two successive interstices between the fire-bars, the said
stoking blades E forming, together, a kind of fork. To the underside of the
stoking lever D) are secured two lugs F, forming a bearing, which rests astride
upon the rod C. By the described arrangement, the operator is enabled, by means
of the lever D to push the two slides B forward or to draw them backward, and
he is also enabled to move the said lever I laterally along the rod C, and conse-
quently to bring the stoking blades E below any desired part of the grate.
From the foregoing statement, the handling of this modification of my feeding,
stoking and cinder-breaking device, forming the subject of my Patent No. 2298,
dated January 28th 1898, will be obvious. When the stoking lever D is at rest,
it is in the position shewn in dotted lines in Figure 1. wherein the handle of the
said lever is lowered and the stoking teeth E project into the heap of fuel main-
tained at the rear end of the grate by periodically opening the slide of the charg-
ing hopper H. By raising the handle of the stoking lever D), the stoking blades E
are lowered below the fire-bars, whereupon the stoking lever D can be moved

page_text: laterally along the cross-rod C in order to bring the stoking blades E below the
interstices between the firebars, where stoking is required. Afterwards the
operator lowers the handle of the stoking lever D, in order to cause the stoking
blades to enter the heap of fuel; practice will soon enable the operator to regulate
the extent to which the handle is lowered to the quantity of fuel to be pushed
along the grate. By then pushing forward the stoking lever, the stoking blades E
are caused to advance in the interstices between the fire-bars they have entered
thereby pushing the fuel forward and clearing the said interstices.
The ashes and broken cinders drop through the said interstices, while the larger
pieces of slag and cinders are caused to fall through the aperture.J between the
grate and the firebridge, and thus reach the ashpit. A slide or trap may be pro-
vided for closing the aperture J; when, however, the furnace has been in work
for a certain time, the said aperture becomes closed by the accumulating cinders.
After having pushed the stoking lever D forward the whole length of the grate,
the handle of the said lever is raised again, so as to lower the stoking blades E
below the grate, whereupon the stoking lever is completely drawn back and
released. It is obvious that the described feeding and stoking can be carried out
once or several times as required.
In the modification illustrated in Figure 3, the slides B are replaced by small
carriages B, mounted on rollers which run in U-iron bars A¹.
In the modification shown in Figure 7 the U-iron bars are replaced by a guide-
way, which may be regarded as composed of two superposed U-iron bars the upper
of which has inclined end portions opening into the lower one. Supposing the
carriage B to be pushed forward from the position shewn by means of the stoking
lever, the carriage will rise over the hinged switch-tongue into the upper guide-
way, and arriving in the front end of this upper guideway it will descend along
its inclined end portion and thus get into the lower guideway again, along which
it may be withdrawn. It will be seen that, in this case, the raising and lowering
of the stoking blades is operated by the specially formed guideway, consequently
the operator, having placed the stoking blades below the desired interstices
between the firebars, has only to push the stoking lever home forward and to
draw it backward.
The raising and lowering of the rear end of the stoking lever I can also be
dispensed with by employing the folding stoking blade E shown in Figures 4
and 5. It will be seen that the said stoking blade E is made to move upon a
pivot in the fork-shaped front end of the stoking lever D, which, in this case,
is by means of a hook G suspended from the cross-rod C. In a slot in the rear
end of the stoking lever D, an angular lever is pivoted by means of the pivot
pin b, and a draw-rod connects the lower arm of the angular lever with the
lower end of the stoking blade E. The construction may be such that the stoking.
blade E folds down under the action of its own weight, when the rear end of the
lever is not pressed down against the handle of the stoking lever. Or as shewn,
a spring may be provided for keeping the lever a in the position corresponding to
the folded down position of the stoking blade.
In the stoking lever D, shown in Figure 6, provision is made for turning the
stoking blades E sideways, as indicated by dotted lines in the end view, after
having lowered them beneath the grate by raising the handle of the stoking lever:
the stoking blades having been turned aside, the stoking lever can be moved
laterally. In order to allow of turning the stoking lever as is necessary when
handling it as described, I form the bearing, by means of which the stoking lever
is adapted to swing round the cross-rod C, of a grooved pulley or disc G³.
It will be seen that the stoking lever is adjustable as regards its length, being
composed of two telescoped parts, which can be locked together in any required
position.
This modification of my feeding and stoking and cinder-breaking device can he
used not only with grates having straight interstices between the grate-bars, but

page_text: also with grates having wavy interstices, and it remains serviceable even when
the fire-bars are much distorted by heat.
In Figures 1 and 2, a grate is shewn, which consists of a number of gridiron-
shaped lengths L, slid into grooves in the frame Ml supporting the grate. Below
the grate, the sides of the frame M are provided with other grooves N, in which
run the rollers of the carriages l' connected by the cross-bar C supporting the
frame-shaped stoking lever D. By cross cuts, the top portion of each fire-bar is
divided into a number of sections adapted to dilate and contract freely.
It will be readily understood that a stoking blade advancing along an inter-
stice between two firebars can never push forward the whole of the fuel it meets
in its path, but, each fragment of fuel struck by the advancing blade will be
carried along a short distance, and, in consequence of its irregular shape, it will
then turn aside, whereby gradual feeding is secured. It may happer, however,
that a large piece of fuel, pushed forward by a careless fireman, will denude a
strip of the grate fuel. Such occurrences are avoided by the divided grate just
described, as thereby the fireman is obliged to carry out the stoking and feeding
operations in several stages or intermittently.
The comb-shaped stoker shewn in Figure 3" consists of a triangular cast iron
body or back O' in which the lower ends of the stoking blades are secured by
inserting them in the mould when casting the back O, and of the stoking blades
proper, connected to the separate lower ends by rivetted thin flat springs,
Figure 4 shows a stoking comb, formed of a section of tube having slots in
which the stoking plates E are inserted.
In the furnace shown in Figures 8, 9 and 10, the firebars R' are made tubular,
in order that they may be cooled by air flowing through them in the direction of
the arrows 1, 1, . . and so prevented from becoming distorted. The sides A²
and the cross portion A' of the frame supporting the grate are likewise made
hollow for the same purpose and have air Howing through them as indicated by
the arrows 2. The heated air thus obtained is utilized for supporting combustion,
and the ashpit is normally kept closed. It is obvious that the stoker must be
unhooked and withdrawn from the ash pit before closing the door of the same.
The carriage B upon which the stoking lever D is fulcrummed, has a second cross-
rod C, by which the raising of the stoking blades is limited.
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:-
1. In a mechanical feeding, stoking and cinder breaking device, the combination
with the grate of a closed fire space above the same, means for maintaining a
heap of fuel upon the rear end of the grate, a two-armed lever the fulcrum of
which is adapted to be moved lengthways and sideways below the grate, and a
comb-shaped stoker secured to the front end of the lever and adapted to have its
teeth or blades introduced into the interstices between the firebars, substantially
as, and for the purpose, described.
2. In a mechanical feeding, stoking and cinder-breaking device, defined by the
First Claim, slides or carriages, movable in guideways below the lateral edges of the
grate, and connected with each other by a cross-bar, which forms the pivot for
the stoking lever, and along which the said lever can be laterally moved, sub-
stantially as set forth.
3. In the mechanical feeding, stoking and cinder-breaking device, defined by
the First and Second Claims, two superposed guideways for the slides or carriages,
the said guideways having their ends communicating with each other, substan-
tially as set forth.
4. In the mechanical feeding, stoking and cinder-breaking device, defined by
the First Claim, pivoted stoking blades, so connected by a draw-rod to a lever
pivoted to the stoking lever near the handle of the same, as to allow the blades
to be folded down before withdrawing the stoking lever, substantially as set forth.

page_text: 5. In the mechanical feeding, stoking and cinder-breaking device, defined by
the First Claim, a grate composed of a number of gridiron-shaped lengths slid into
grooves in a frame, substantially as set forth.
Dated the 4th day of October 1899.
G. F. REDFERN & Co..
4, South Street, Finsbury, London, Agents for the Applicant.