Improvements in and connected with Mechanical Stokers.
Year: 1895

page_text: Date of Application, 1st Apr., 1895
Complete Specification Left. 2nd Nov., 1895-Accepted. 14th Dec., 1895
Date of Application, 1st Apr., 1895
Complete Specification Left. 2nd Nov.. 1895-Accepted. 14th Dec., 1895
PROVISIONAL SPECIFICATION.
Improvements in and connected with Mechanical Stokers.
WALTER ARTHUR AYRES Dace Road Bow, in the County of London,
Engineer and HAROLD PELHAM RANGER 56 St. Georges Road Leyton in the
County of Essex, Engineer do hereby declare the nature of this invention to be as
follows:-
This invention relates to improvements in the manufacture and arrangement of
mechanical stokers for furnaces and known as coking stokers.
The object of our invention is to construct a coking stoker to effectively feed
the coal continuously in regular quantities across the whole width of the furnace,
from an opening above the top of the furnace door, thus forming a bank or ridge of
coal to be coked in the front of furnace before being carried to the back.
We attain this object by feeding the coal through a hopper by means of
propeller shaped blades joined to a shaft or spindle which is caused to rotate at
any desired speed, the coal is thus propelled through a slot shaped opening upon
inclined guide plates on to a perforated dead plate below, by this means the coal is
equally distributed across the furnace and after being partially coked is carried
by moveable fire bars to the back end of the furnace.
The movement of the fire bars is such that every alternate bar is caused to rise
slightly above the level of the remaining bars which are fixed, and travel the
required length of feed through the furnace. These bars on their return journey
fall below the level of the fixed bars, thus breaking up the clinker, clearing the air
spaces, & moving the partially consumed coal forward effectually. For this
purpose we propose to fix beneath the bars a cam shaped rotating shaft, working
under or in suitable openings formed in the bars. This shaft is driven by a ratchet
wheel and gearing with an arm projecting in front of boiler and provided with a
long slot for varying the speed, or by other suitable gearing. We also propose to
make the guide plate from the hopper and which extends inside the furnace to
close up when required, thus shutting off the coal contained in the hopper from
the lighted coal in the furnace and preventing the necessity of emptying the hopper
when the stoker is not at work.
We also when required arrange to carry the bars upon suitable carriages
running upon a track fixed to the sides of the furnace tube and worked by means
of excentrics or other gear attached to a shaft in front of boiler in such a manner
that the bars move alternately and pause, at the end of each stroke to enable the
coal to be properly burned before leaving the bars.
Dated this 30th day of March 1895
WALTER ARTHUR AYRES.
HAROLD PELHAM RANGER.

page_text: improvements in and connected with Mechanical Stokers.
We, WALTER ARTHUR AYRES of Dace Road, Bow, in the County of London,
Engineer and HAROLD PELHAM RANGER of 56 St. Georges Road Leyton, in the
County of Essex, Engineer, 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 :-
Our invention relates to improvements in the construction and arrangement of
mechanical stokers for furnaces, and known as coking stokers, the object of our
said invention being to so construct a coking stoker as to effectively feed and
spread the coal continuously and in regular quantities across the whole width of
the furnace, from an opening above the top of the furnace door, thus forming a
bank or ridge of coal to be coked in the front of the furnace before being carried
by moving fire bars to the back of same, and we attain this object by first feeding
the coal into a suitable hopper or receiver, the capacity of which may vary
according to the size of the furnace, and consequently the quantity of coal
consumed, and through and from the said hopper the coal is fed by the means of a
series of propeller shaped blades cach joined to, and radiating from, a sleeve or
collar mounted upon a shaft or spindle, caused to rotate intermittantly at any
desired speed, and by these, the coal is thus propelled through an aperture or
opening in the furnace, on to an inclined guide, plate or plates, and from this or
these directly upon a perforated dead plate below, and by this means the coal is
equally distributed across the front of the furnace, and by the before mentioned
movable fire bars conveyed to the back end of same into the coke pit.
In order that our invention and the manner of its application and operation may
be fully and clearly understood we have hereunto appended a sheet of drawings, in
which we have chosen to illustrate its application to the right hand furnace of a
double furnaced horizontal boiler.
Fig. 1 is a front elevation of our improved mechanical stoker fixed in position.
Fig. 2 is a longitudinal vertical section taken centrally or thereabouts of Fig. 1,
between one of the fixed bars, and one of the movable bars according to our
invention.
Fig. 3 is a vertical cross section of the furnace and fire bars taken centrally of
the length of the latter or thereabouts.
Fig. 4 is a side elevation of the back end of the fire bars, illustrating the
manner in which we prefer to construct these with a removable and renewable
portion at the part at which the greatest wear usually occurs, Figs. 5 and 6 being
plan and side elevation respectively of the said removable and renewable portion.
Figs. 7, 8 and 9 are enlarged top, front and side views respectively of one of the
said propeller like blades, and its rectangular or polygonal sleeve or collar to
which it is connected.
"
.
Fig. 10 is an enlarged diagram illustrating the method of operating the
intermittant feed of the coal and the moving firebars as hereinafter explained.
Fig. 11 is an enlarged section of the lower surface of the feeding aperture
illustrating the manner in which we prefer to pivotally connect thereto the
distributing guide plate and the mechanism employed for raising the saine for
closing the said aperture, às hereinafter explained.
Figs. 12 and 13 are enlarged and detached plan and front views respectively of
the said guide plate.
Fig. 14 is a plan view of the fire bars of the furnace, showing partly in section
the mechanism for operating such of these as are movable according to and for
the purposes of our invention.
We carry our invention into effect by casting or otherwise constructing of sheet

page_text: iron or other suitable metal, a casing A, preferably of the shape shewn in
Figs. 1 and 2, the lower mouth of which a is passed through and fits an aperture in
the furnace B, just above the door C, whereat the said casing is bolted or other-
wise fixed, the upper mouth of which is constructed to receive a hopper D,
preferably shaped and provided with a sloping mouth, as at Figs. 1 and 2.
Through the said casing A passes a horizontal spindle or shaft E, preferably
rectangular or polygonal in cross section for so much of its length as is enclosed
within A, and upon this portion is mounted a series of short sleeves or collars b,
each having attached thereto, or formed integrally therewith, and extending out-
wardly therefrom a propeller like blade c (shewn detailed by Figs. 7, 8 and 9) the
said sleeves or collars being arranged in such a manner upon the said shaft E, that
the said blades form a helix or spiral projection radiating therefrom. Or in lieu of
a series of said sleeves beach carrying a blade c, we may employ one such sleeve
of a length equal to the said series, from which the desired number of blades c may
project in like order.
The shaft or spindle E being carried in suitable bearings (which may or may not
be the ends of the casing A) has pivotally mounted upon one end thereof a pair
of triple eared plates, such as F Fig. 10, the upper and lower cars of which d
and respectively, are bolted together in such a manner that a space exists
between them, and in this space is mounted, and keyed or otherwise fixed upon
the shaft E, a ratchet toothed wheel such as G Fig. 10, but with its teeth in
reverse order to that shewn, if this be mounted upon the right hand end of E as
at Fig. 1, while a weighted pawl e is mounted upon the bolt connecting the lower
ears and engages with the teeth of G. The third pair of cars d" of the plates F
are at right angles with dd, and are bolted together in like manner, and upon
this bolt is pivotally connected the lower end of a vertical rod H, the upper end
of which is connected to a short crank, cam, or eccentric upon a power shaft, or
to any other suitable motion by which an up and down vertical movement may be
imparted thereto, an adjustable slot in the upper end of which rod may if necessary,
be employed to govern the extent of such movement.
The fixed fire bars J of the furnace are preferably borne at the front or both
ends upon a transverse bar or bars, plate or plates f, rendered adjustable vertically
by a set screw such as g (Fig. 2) while the movable bars K are preferably recesserl
upon their under surfaces at and f", and when in their normal positions rest upou
transverse bars or plates and rendered adjustable vertically by set screws such
as, the said movable bars K extending at their front ends beyond the fixed
bars J whereat they are each provided with an aperture m preferably but not
imperatively formed as shewn in Fig. 2, but which may vary according to the
motion desired to be imparted to these bars as heroinafter explained, but for the
purposes of description, we assume that they are so formed, and passing through
these recesses is a cam shaft or spindle L, the bearing ends of which are journelled
in suitable brackets such as M'M', and that extending through the latter, has
keyed or otherwise fixed thereon a ratchet wheel G, and pivotally triple-car
plates F, the upper and lower cars of which are bolted together in the same
manner as the plates F before described with the lower one carrying a pawl
(Fig. 1) substantially as at Fig. 10. To the central or horizontal cars n of the
plates F, is pivotally connected the lower end of a rod H', the upper end of which
is connected to the lower end of the rod H before described, such connection
between H and H¹ being either by a link or by forming two eyes in the ears "
of F the upper eyes of which may be connected to the lower end of H while the
lower eyes may be connected to the upper end of H' as suggested by dotted
outline in Fig. 2, the object of this being that the vertical movements of H
and H may be identical.
Referring again to the casing A, and the view Fig. 11 the lower surface of the.
mouth a of this has pivotally connected thereto a guide plate N, upon the upper,
surface of which are radial ridges p, and the said plate is arranged to be raised
and lowered by the means of a worn wheel O fixed upon one of its pivotted ends,

page_text: engaging with a worm P operated by a wheel or handle such as r, and when the
plate N is lowered as shewn by the full lines in Fig. 2 this and its ridges p serve
to distribute the coal fed through a thereonto, on to a perforated plate R and from
this on to the initial end of the fire bars, but when (as shewn by dotted lines in
Fig. 2) the plate N is raised, this closes the mouth of a and prevents the coal in A
from becoming ignited by the flame from the furnace.
Referring again to the fire bars J and K, it is found in practice that these burn
and wear out at their back ends more quickly than elsewhere, and to accommodate
such wear we construct this end of these renewable, by forming in that part of
the bars a recess such as s (Fig. 4), and to occupy such recesses we provide portable
pieces such as t (Figs. and 6) which may be of chilled iron or steel, and are
retained in position by forming the ends of these V shaped as at Fig. 5, and
providing like shaped apertures in the fire bar at each end of the recesses 3, with
which the ends of t engage as shewn in Fig. 14, suitable pins or dowels w upon t
engaging with like holes in the fire bars.
The manner of operation is as follows:-
The coal being deposited in the hopper D, and intermittent motion imparted to
the rods H and H', the former of these rods by oscillating the plate F, would, by
the agency of the pawl e, impart an intermittent rotary motion to the ratchet G,
and consequently the shaft E, and the propeller like blades c thereon in the
direction of the upper arrow Fig. 1, the said blades regularly and evenly breaking
the coal and pushing it through the open mouth of a, on to the guide plate N,
which by reason of the formation of this and the ridges thereon, the coal would
eventually be deposited evenly and in all directions on to the front or initial end
of the fire bars J and K.
The intermittent vertical motion of the rod H would impart a like motion to
the rod H', and this by oscillating the plates F, would by the agency of their
pawl e impart an intermittent rotary motion to the ratchet wheel G₁, and con-
sequently the cam shaft L in the direction of the lower arrow Fig. 2, and this in
its course of rotation would by colliding with the upper portion of the aperture m,
first raise all the bars K above the fixed bars J, and continuing ou, the said cam
would push the same bars backward in the direction of the arrow X Fig. 2 and
as the wider portion of these near the recess f" slide upon the bar ¾¹, the back
ends of K would be also raised and by the return motion of the cam L, the said
bars K would be again returned to their normal position as shewn in Fig. 2.
By this means the whole of the alternate bars K are caused to rise above the
fixed bars J and travel horizontally between them, once to every revolution of the
cam shaft L, and by the adjustment of the screws h', the same bars K may in their
return motion fall below the level of the fixed bars J, and by this continued
horizontal motion of the bars K, the fuel would be gradually carried from the
front to the back end of the bars in short and regular stages, the rise and fall of
these above and below the bars J serving to break up the clinkers, clear the air
spaces, and effect perfect combustion of the fuel, ultimately depositing the
exhausted portion of this into the coke or clinker pit at the end of the bars in the
usual way.
We may find it convenient or desirable that certain of the bars K may have
a motion differing from, or to a greater or lesser extent than the others, and it is
obvious that this may be easily effected by altering the shape length or height of
the apertures m.
The method of and means for raising the guide plate N for closing the mouth a
will be fully understood, and the necessity for doing so fully conceived by all
persons conversant with stoking without further explanation.
Having now particularly described and ascertained the nature of our said inven-
tion and in what manner the same is to be performed, we declare that what we
claim is :-

page_text: suitable motive power, imparting a reciprocating motion, and the means for
conveying such motion for intermittently rotating a shaft carrying propeller like
blades, and the mechanical means for regularly and evenly conveying the coal
from the hopper, in combination with a ribbed guide plate operating for distributing
the same the whole breadth of the furnace, and closing the mouth of said hopper
when desired and the mechanism for effecting such closure, substantially as herein
described and shewn.
2nd. In an improved mechanical stoker for furnaces the employment of an
intermittently rotated cam shaft, and the mechanical means for effecting and
regulating the degree or extent of such intermittent motion, for imparting a
horizontal travel, and rise and fall or other motion to certain or every alternate
fire bar, substantially as and for the purposes herein described and shewn by the
accompanying drawings.
3rd. In an improved mechanical stoker for furnaces the combination of a casing
such as A, carrying a hopper or receiver such as D, and having a mouth such as a
entering the furnace B, and carrying a guide plate such as N, arranged for closing
the mouth of a by suitable gearing such as O, P operated by a wheel or handle r.
The shaft E carrying propeller blades such as c arranged in helical form,.
intermittent motion being imparted to said shaft by the means of a ratchet
wheel such as G, operated by a pawl such as e carried upon a double plate such
as F mounted upon E, and caused to oscillate by the means of a rod H receiving
intermittent motion from a cam crank, eccentric or the like, operated by a power
shaft, the whole connected, combined and operating substantially as and for the
purposes herein described and shewn by the appended drawings.
4th. In combination with the mechanical stoker set forth in the preceding claim,
the construction, use and application of a cam shaft such as L, intermittently
rotated by the means of a ratchet wheel such as G', operated by a pawl such as el
upon a double plate such as F1 mounted upon L, and caused to oscillate by the
means of a rod H', connected by a link or otherwise to, and receiving motion from,
the rod H. The employment of the cam shaft L for imparting vertical and
horizontal motions to the movable fire bars K, having apertures such as m, and
mounted upon adjustable bars / h, and arranged alternately between fixed bars J,
the said bars K and J having removable and renewable portions such as t, the
whole connected combined and operating substantially as and for the purposes
herein described and shewn by the appended drawings.
5. In an improved apparatus for mechanically stoking furnaces, the construction,.
use and application of the herein described combination of parts and the method
of and means for imparting motion to the movable sections of same, substantially
as herein described and shewn by the drawings hereunto appended.
Dated this 2nd day of November 1895.
GEO. THOS. HYDE,
1 Broad Street Buildings, Liverpool Street, London, E.C.,
Agent for the Applicants.