Improvements in and relating to Mechanical Stokers.
Year: 1898

page_text: Date of Application, 11th July, 1898
PROVISIONAL SPECIFICATION.
Improvements in and relating to Mechanical Stokers.
I, JEAN WAGNER, Engineer, of 29, Rue du Chateau d'Eau, Paris, in the
French Republic, do hereby declare the nature of this invention to be as
follows:-
My invention relates to a mechanical stoker for a steam boiler furnace which
works in three periods in a continuous manner.
(a) During a first period, viz., the feeding or charging period, the grate
receives at its forward end a determined quantity of coal.
(6) During the second period of the continuous operation of my mechanism,
the said quantity of coal is burned.
(c) During the third or last period, the gradual advance of the said charge of
fuel is effected by mechanical means from the first fixed steps or bars, in an
incandescent state, to the last fixed step or bar, and so on, until it is completely
expelled from the entire area of the grate in the form of residue, ashes, etc., whilst
however leaving a convenient space for the reception at its forward end of fresh
charges of coal.
According to this invention the fuel is supplied continuously into a hopper by
means of a worm or endless screw. This hopper is placed above the fireplace of
the boiler where the fuel remains whilst awaiting its distribution on to the grate
of the fireplace as I shall now proceed to describe.
My principal actuating mechanism consists at the upper part of my general
installation, of a horizontal shaft operated by a worm or endless screw wheel,
said endless screw being keyed on a motion shaft which is the principal and
driving shaft. The endless screw actuates this wheel directly with the result that
the speed of the rotation of the horizontal shaft is relatively small compared to
that of the main shaft. I thus obtain show movements of the lever of the rotary
coal distributing device and also for the advance and return movements of the
movable steps of the furnace. The horizontal shaft rests in two bearings mounted
on brackets fixed to the ceiling. At the longitudinal centre of the horizontal
shaft and revolving as one piece with it, there is a gun metal sleeve which is
provided externally with a right hand screw thread, and with, another but oppositely
directed screw thread, forming the continuation of the first screw thread, that is
to say with a left hand screw thread. In the groove formed by the cross threads,
there engages a guide provided with two lugs it takes in the bottom of the said
groove and an attached vertical spindle provided with two nuts, rocks freely in
the middle of a hole formed in the thickness of an encircling cylinder. This
cylinder is provided with two arms having round sleeves, sliding freely on a
second horizontal shaft carried by suitable bearings parallel to the first one.
The arrangement is such that when the main shaft revolves, the guide draws
with it longitudinally the cylinder in one direction or the other according to the
direction of the threads of the sleeve.
The cylinder carries loosely or freely between two half collars which are re-

page_text: tained by means of screws, a cone or toothed clutch, the hub of which forms one
piece with a long feather fixed on the horizontal shaft so that said clutch when
revolving with the said shaft and in the same direction will engage longitudinally
in a similar cavity which is also toothed. I am thus at the commencement of the
first active period for the exclusive introduction of a determined quantity of coal
situated as I have above stated, in the interior of the hopper of the furnace.
The capacity of the hopper is variable, but the quantity of coal which falls will
always be the same, unless by means of a hand crank the position of a metallic
horizontal plate be varied, or the travel of a distributing lever be stopped,
by withdrawing a shaft by hand which constantly connects a connecting rod and
the lever. The constant arrival of the fuel in the hopper allows always of having
a regular charge for feeding the grates.
In order to carry out the general arrangement of my invention I have described
the screw sleeve having two threads of contrary directions, as having a speed of
two revolutions per minute with a right or left hand pitch of 40 mm., and I thus
obtain at the commencement of the initial operation, for the first minute (outward
stroke) and for the second minute (return stroke) four revolutions of a cam which
is in one with a drum and which produces in its rotation the descent of the
connecting rod. This latter during this said period of feeding then imparts an
alternating movement to the lever having a slot and a counterweight.
The lower end of this connecting rod serves to actuate the lever and the other
upper end of the connecting rod remains suspended almost vertically from the eye
of a lever arm rocking about a fixed axle that is carried by a bracket fixed to
the ceiling.
The lever is provided with a pawl entering in the teeth of a ratchet wheel which
is fixed to a shaft provided with vanes. This pawl moves with a shaft at each
oscillation of the lever for the purpose of allowing only that quantity of coal
which is exactly necessary for the combustion of the furnace to fall down. By
using a second pawl the return movement of the shaft in a backward direction is
prevented.
But
During the four revolutions of the upper or horizontal shaft, the following
has taken place:-By the use of the clutch, the toothed cavity having a cylindrical
periphery slides freely in a cylinder. A key fixed to the toothed cavity allows
of the cylinder being rotated by the cylindrical periphery of the toothed cavity and
consequently of a rotation of a cylindrical sleeve which in its turn is attached by
means of screws to the drum that receives or contains the distributing cam.
at each revolution of the horizontal shaft the guide advancing with the pitch
already referred to (in this case 40 mm.) the result is that the cylinder periphery
of the toothed cavity compresses a coiled spring whilst on the change of the direction
and motion of the guide in arriving at the end of the right hand thread in order
to engage with the left hand thread, the spring expands and returns all the
cylindrical parts to their positions. The exclusive period of distribution of the
determined quantity of coal is terminated, two minutes have passed, and an
inoperative phase is about to commence.
During the third minute (return movement) and the fourth minute (return
movement) the horizontal shaft will have rotated 8 times without doing any
mechanical work so as to leave time for the fuel charged into the furnace of
the boiler to become ignited upon the fixed bars of the first forward section of
the grate. During the fifth minute (return movement) and the sixth minute
(forward movement) the four revolutions of the shaft will do the following
mechanical work:-
At the other end of the horizontal shaft are mounted a drum, cylinder and
cylindrical sleeve similar to those before described, in such a manner that a
toothed clutch, arriving at the fifth revolution in contact with the toothed cavity,
moves it along during this fifth and sixth minute and consequently first com-
presses its coiled spring, causing the cylinder and cylindrical sleeve to rotate,
and since a pinion is fixed to the drum it is rotated so as to drive a large toothed

page_text: wheel. The second shaft which remained stationary up to the fifth minute will
only make one revolution up to the end of the sixth minute. The single
revolution of the said shaft has for object to operate a crank and its crank pin
which enters in a slot of a large lever forming part of the advance and return
movements of the movable slides. By reason of the complete revolution made by
the crank pin the large lever is caused (by being keyed upon a horizontal shaft
carried by stay pieces) to thus produce the longitudinal displacement of all the
movable slides, but with different strokes which depend upon the height at which
they are connected to levers, that are keyed upon the said shaft. Nevertheless
I reserve the right of imparting any desired speed to the worm or endless screw
wheel.
The furnace is bounded at its forward part by a plate of the front casing
provided with doors and of which one serves for igniting purposes and for allowing
the opening of a removable door, whilst those of the lower part are intended
to take in a supply of external air for conveying it into the ash-pit. The total
area of the grate consists substantially of cast iron bars which can be readily
replaced, and which are divided into sections of unequal sizes depending on:-
(a) My mode of partial and periodical introduction of the determined quantity
of fuel.
(b) On the mechanical arrangement which actuates the movable slides.
(c) On the connection or relation which exists between the two periods a
and b.
The fixed bars of the various sections of the grate of the furnace rest upon
horizontal tubes which are carried by longitudinal girders. The girders of the
inclined bars near the door are made of round section iron. These tubes are
utilised for the purpose of conveying external fresh air which becomes heated
in its passage inside its tubes, to near the hopper, into a gallery formed of
refractory brickwork the lower part of which consists of a flag-stone of refractory
earth perforated with orifices. The heated air flows out on to the first quantity
of coal introduced as above described, and still in its fresh state, with the purpose
of effecting an intimate mixture with the gases of combustion.
The upper surfaces of the bars of all the sections of the furnace grate serve as
a horizontal bearing for the total longitudinal travel of movable slides which are
actuated by vertical levers fitted in caps provided on its ends and at the sides of
each arm of the movable slides. These arms and those on the opposite side slide
freely on fixed cylinders. The outer ground level and the inner ground level
constitute a difference of level in which at the lower end of the last section of
the grate there is a sealed metallic and perforated plate which closes the bottom
of the lower part of the ash-pit. A shaft operated by a hand-lever serves to
operate the perforated sector so as to close or open the air-holes in the perforated
plate. Finally near this plate there is arranged a passage for discharging the
ashes which remains closed by a horizontal grating. All the non-combustible
residues fall upon this grating and in the evening the stoker tips it up by
operating a hand lever.
Previously these residues have been moved along imperceptibly by the herein-
before described movement of the levers the initial and rest axial positions of which
are almost vertical. A lever operates a horizontal bar and then the latter acts
upon a small connecting rod and the grating throws down into the passage the
residues which are subsequently removed, so as to insure the regular working of
the fresh charges of coal falling from the hopper. On releasing the lever the
grate returns to its original horizontal position.
In an arrangement of a furnace in which the slides are slightly inclined, the
two horizontal shafts have a cam and a crank pin. The cam operates at each
effective revolution a vertical connecting rod in the manner already described.
A lever describes a circular are having an angle equal to that inscribed between
each distributing vane by reason of the use of an operating pawl whilst at the
return of the lever into its original position an arresting ratchet prevents the

page_text: return backward movement of the vanes. In this manner I obtain a first period
of feeding the necessary quantity of coal and, as in the above case, in the same
period of time of two minutes.
The third and fourth minutes are occupied in allowing the coal to fall towards
a movable slide and to remain also upon the bars of a fixed grate in order to
become ignited. The result. is that the gun metal sleeve operated without doing
any mechanical work which can be utilised for the furnace of the boiler.
During the fifth and sixth minutes the horizontal shaft causes the second
horizontal shaft to make a complete revolution by means of the pinion and the
toothed gear wheel thereon. This shaft produces a circular movement of. the
crank pin in the slot of the connecting rod, in such a manner as to impart a
single alternating movement to levers. As these levers are keyed on a shaft the
said levers will describe, in the manner in which I have arranged them, an are
of a circle having the same angle as that described by the connecting rod. This
alternating movement during the fifth and sixth minutes of the levers has for
object to move forward and to bring back into the normal position slides or
movable steps in such a manner as to clean the fire and take along the incandescent
fuel from the first step towards a fixed inclined grate which is provided at the
bottom of the furnace.
The bars have rollers of suitable diameter so that they can be moved without
jolting during the upward movement of connecting rods, with the object of
effecting the cleaning of the furnace and the automatic travel of the coal from
one step to the other. Finally, during the return travel when the crank pin of
the second shaft returns the connecting lever, to its initial position it is found
that the coal has been moved along by undulating motion whilst leaving during
the new period of rest a very smooth incandescent surface. The gun metal
sleeve after the return of the lever into its initial position again leaves the
parts of the boiler furnace at rest during the seventh and eighth minutes. Finally,
during this rest period, the coal, after complete combustion, becomes converted
according to the rank of the step it occupies, into residues, ashes, etc., which
will then be expelled from the furnace at the next cleaning movement, that is
to say, on to a grating so as then to fall finally upon a tipping grate.
A cylinder with a union is provided for the entrance of external air in such
a manner that according as the air is heated by the waste heat of the furnace it
moves forward and escapes under the first movable step. Whilst the external
air passing slowly through the pipe girders of the fixed bars, in the middle of
the gases produced by the combustion of the coal charged upon the front portion
of the grate and which is beginning to enter upon a period of incandescence.
Dato il 1141 of Tul, 1908
ROBERT E. PHILLIPS, Assoc. M.Inst.C.E., M.I.Mech. E.,
Chartered Patent Agent,
70, Chancery Lane, London, W.C., Associate Agent.
I, JEAN WAGNER, Engineer, of 29, Rue du Chateau d'Eau, Paris, in the
French Republic, 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:-
My invention relates to a mechanical stoker for the furnace of a steam boiler,
which works in a continuous manner in three different phases, namely, (a)

page_text: during the first period, that is to say during the period of charging, the grate
receives on its forward end a determined amount of coal. (b) during the second
period of the continuous working of my mechanism, the said amount of coal
is piled up. (e) during the third or last period, the progressive forward movement
of the raid charge of fuel is produced by means of a mechanical device, starting
from the first fixed steps or fixed bars, in the incandescent state, towards the
last step or bar, and so on, until it will have been completely pushed back from
the whole surface of the grate in the form of residue, ashes ctc., whilst leaving a
suitable space for receiving at its forward end a fresh charge of coal.
Figure 1 is a perspective view and also a longitudinal section of the general
arrangement of my mechanical stoker. Figures 2, 3 and 4 are respectively on
a larger scale an elevation, plan, and section of the mechanism for producing the
above described periods a, b, c. Figure 5 shows in elevation and in section the
mechanism for moving forward and moving back the movable steps when they are
required to clean the furnace. In Figure 6 I have shown the symmetry of the
two movements which combine together to produce an automatic cleaning.
Figures 7, 8 and 9 are respectively views in elevation, in plan, and in section,
of a movable step and its arms. Figure 10 shows in elevation and in section
the arrangement for cleaning the first inclined bars arranged at the front of the
furnace and Figure 11 is a plan thereof. Figure 12 shows the arrangement of
the hand crank, of the tooth pinion and of the rack bar which forms one with
the plate that regulates the arrival of the fuel when it falls from the receiving
hopper. Figure 13 is a front elevation of the lever operating the shaft of the
device for periodically distributing the fuel, and Figure 14 is a side elevation
thereof.
Referring to Figure 1, the boiler furnace is bounded at its front end by a large
cast iron plate 1, provided with two movable doors 2, 3, of different dimensions;
the door 3 of the lower part is designed to take in supplies of the exterior air
in order to allow it to remain in the ashpit, whilst the movable door 2 as also the
doors 4 and 5 situated above the ash-pit, serve for the ignition of the fuel on
starting the operations. A conical spy hole formed in the thickness of the wall facili-
tates the supervision of the fire. The two side faces of the metallic part of the furnace
are also connected together by means of bolts with the plate 1, and with two
longitudinal and similar girders 6 (Fig. 1) for the purpose of ensuring complete
stability between the two mechanisms, one of which operates on the outside,
whilst the other operates on the inside. The degree of inclination of the movable
and fixed steps is variable, and I conform to the technical conditions which
may give the best utilisation of the fuel under a boiler which is to be provided with
my invention. The top of the movable and fixed steps may be horizontal, or
inclined as shown in Figure 1. In this invention the fuel is conveyed in an
uninterrupted manner into a hopper 7, by means of an endless screw 8. This
hopper 7 is situated above the furnace of the boiler, and the fuel remains therein
whilst awaiting its distribution over the surface of the grate of the furnace,
as I shall now proceed to describe. My principal motive mechanism is situated
at the upper part of my general arrangement, and consists of a horizontal shaft 9
(Figures 1, 2 and 3) operated by a wheel 10 from an endless screw 11, keyed
on the driving shaft 12 which constitutes the main shaft. The endless screw 11
operates directly in such a manner that the speed of the rotary motion of the
horizontal shaft 9 is relatively small in relation to that of the main shaft 12.
I thus obtain slow movements of the rod 13 (Figure 1) of the coal distributing
device, as also the movements of the big vertical lever 14, keyed to a horizontal
shaft 15 which is itself provided with cranks 16, 17 and with connecting rods 18, 19
(Figures 1, 5 and 6) which produce the forward and backward movements of the
movable steps 20, 21, 22 (Figures 1, 7, 8 and 9) of the furnace, which have the
function of automatically cleaning the fire, and each of which is formed by a
metallic plate perforated as shown in section in Figure 9. The horizontal shaft 9
is carried in two bearings 23, 24 (Figure 3) arranged on metal brackets 25, 26,

page_text: fixed to the ceiling, and the shaft 9 turns in the direction indicated by the
arrow in Figure 3. In the longitudinal centre of the horizontal shaft 9, there
is mounted in such a manner as to rotate as one single piece therewith, a gun
metal sleeve 27 (Figure 3) which is provided externally with a right hand screw
thread and with another but left-handed screw thread, and which forms the
continuation of the first screw thread, that is to say, a left handed screw thread.
In the groove formed by the screw threads that cross each other (Figure 3) there
engages a guide 28, which is provided with two tenons that bear upon the bottom
of the said groove; and a vertical rod 29 with its two nuts 30, 31, oscillates freely
in the middle of a hole formed in the thickness of a jacket-cylinder 32 (Figures 1,
2, 3). This cylinder is provided with two arms 33, 34, with round sleeves 35, 36,
that slide freely on a second horizontal shaft 37, mounted in bearings 38, 39,
suitably arranged so that the shaft 37 will remain always parallel to the first
shaft 9. The arrangement is such that when the main shaft 9 rotates, the
guide 28 moves with it the jacket-cylinder 32 longitudinally in the direction of
the screw thread of the sleeve 27. In the present example the guide 28 is about
to begin a useful mechanical work, namely to distribute the fuel
upon the
first step of the grate because the jacket-cylinder 32 holds freely between two
half-collars 40, 41, held by means of screws 42, 43, a cone or sleeve 44, provided
with teeth, and the hub 45 of which is formed of one single piece engaging with
a long key 46 fixed on the horizontal shaft 9 in such a manner that the said
cone 44, when it turns with the said shaft 9, and in the same direction, will
engage longitudinally in a similar recess 47, which is also toothed.
I have now
arrived at the commencement of the first active period (a), for the exclusive
introduction of a determined quantity of coal placed, as above stated, inside the
upper hopper 7 of the furnace. The capacity of the hopper 7 is variable, but the
quantity of coal which falls and follows the path indicated by the arrows 48, 49,
of Figure 1 is always the same, unless the position of the longitudinal metal
plate 53 be changed by means of a crank handle 50 (Figures 1 and 12), of a
pinion 51, and of a rack bar 52, or unless the movement of the distributing
lever 54 (Figures 1 and 13) be arrested by withdrawing by hand an axle 55
which constitutes a permanent connection between the rod 13 and the lever 54
with a counterweight 56. The constant arrival of fuel in the hopper 7 allows
of always having for disposal a regular charge for the purpose of feeding the
total surface of the grate. In order to carry out the general arrangement of
my invention I have given in this example to the screw threaded sleeve 27 a
speed of one revolution per minute with a screw thread of 40 mm. pitch with a
right and left hand direction, and I thus obtain at this commencement of the
working as shown in Figure 3 for the first and second minutes (forward movement)
and for the 3rd and 4th minutes (return movement), four revolutions in four
minutes of the hub 57, the eccentric plate 58 with a groove 59 (Figures 1 and 2)
forming one piece with the drum 60. This groove produces during its rotation the
downward movement of the vertical rod 13, suitably guided so as to follow a
rectilinear path in its forward and return movements, and which during this
period, which I term the feeding period, thus imparts an alternating motion
to the lever 54 with its removable axle 55, and with a counterweight 56. The
lever 54 is provided with a pawl 61, engaging with the teeth of a ratchet wheel 62
that is formed in one with the horizontal shaft 63, having blades 64, 65, 66, 67.
The shaft 63 resting in bearings 68 (Figure 14) is moved along at each periodical
oscillation of the lever 54, so that only the exact quantity of coal which is
necessary for the combustion of the furnace will pass between each blade during
this space of time. By employing a second pawl 69 (Fig. 13), the return movement
of the horizontal shaft 63 is prevented. During the four revolutions in four
minutes of the upper shaft 9, the apparatus has operated as follows:-By reason
of the use of the cone 44, and the toothed cavity 47 provided with a cylindrical
periphery (Figure 3), the latter slides freely in a cylinder 70. A key 71 fixed
to the toothed cavity 47 allows the cylinder 70 to be actuated in a rotary manner

page_text: by the said cylindrical periphery of the toothed cavity, and consequently it
allows of the rotary movement of a sleeve or cylindrical drum 60, which in its
turn is connected by means of several screws 72, 73, 74, to the drum 75, upon
which there is adapted or mounted the plate 57 of the eccentric 58. But at each
revolution of the upper shaft 9, the guide 28, moves forward to the extent above
stated (in this example to the extent of 40 mm.); the result is that the cylindrical
periphery of the toothed cavity 47 compresses a coiled spring 76 whilst at the
time of changing, the direction of motion and when the movement of the
guide 28 reaches the end of the right hand screw thread in order to enter
the left hand screw thread, the coiled spring 76 expands completely, and returns the
whole cylindrical part 47 into the initial position shown in Figure 3. The
period (a) which is exclusively designed for the distribution of the determined
quantity of coal, is now finished, and four minutes have elapsed. An inactive
phase (6) commences, the shaft 9 continues to turn in the same direction indicated
by the arrow in Figure 3. This period of time will continue so long as to
allow the coal to enter into combustion to a considerable extent before being
moved from step to step during the third period (c) mentioned at the commence-
ment of this specification, and which I shall hereinafter describe. Figure 3
shows that, on the side of the pinion 77 and of the gear wheel 78, there are
similar parts to 60, 70, shown in section on the other end of the horizontal shaft 9
already referred to, in such a manner that the toothed cone 79 on reaching the
end of the inactive period (b) will be in contact with the cavity 80, and will push
it back for two minutes and consequently compresses first its coiled spring, and
similar to the one 76, causes 81, 82, to turn, and as the pinion 77 forms one
piece with the drum 82, it begins to revolve so as to actuate the large gear
wheel 78, which moves only during the third and last period (c) herein termed
the period of automatic cleaning of the bars of the grate. The second horizontal
shaft 37, which was stationary up to the moment of contact of 79 and 80, will only
make one complete revolution up to the end of their engagement. The single
revolution of 37 has for object to actuate the crank 83 and its crank pin 84,
which is situated in the guide slot 85 of the lever 14, which forms an integral
part with the forward and return motion of the movable steps on the various
sections of the grate. The big lever 14 by reason of the complete revolution
of its being
made by the pin 84, in four minutes, and by
keyed upon the horizontal shaft 15, (Figures 1, 6,) carried by the
bearings 86, 87, (Figure 6), this lever 14 being moved alternately.
allows of effecting a longitudinal movement in a forward direction and then
in a rearward direction of all the movable steps 20, 21, 22, which rest respectively
upon series of metal bars situated at 88, 89, 90, and which are constantly fixed
by reason of their engaging with hollow passages 91, 92, 93 and with perforated
cross pieces 94, 95, 96. The horizontal shaft 15 communicates in the following
manner its two different angular movements to the movable steps 20, 21, 22.
Cranks 16, 17 fixed at the distance apart shown in Figure 6, receive at their lower
parts the head of a connecting rod, whose opposite end is formed in one piece
with the journal 97 or 98, fixed near the middle of the bar 99 or 100, (Figures 1,
of the movable
5, 6). Upon the bar 99 I fix each arm 101, 102,
steps 20, 21, 22, and upon the bar 100, similar to the one 99, but arranged
symmetrically on the opposite side towards the crank 17, I fix the other arms
of the movable steps in such a manner that at the first angular movement of
the horizontal shaft 15, the movable steps will make an upward movement accord-
ing to the position occupied by the pin S4. This movement is facilitated and
rendered as smooth as possible by the use of rollers 103, 104, 105, 106, (Figure 6)
with axles fixed to the bars 99, 100. These rollers 103 to 106 roll on slide
ways 107, 108 109 110 which are symmetrically fixed along each vertical face
of the ash-pit. By the upward movement of the movable steps 20, 21, 22,
during the first portion of the four minutes reserved for the rotary movement of
the pin 84, a quantity of fuel in the incandescent state passes in this manner from
reason

page_text: at
one step to the other in the direction of the discharge flue 111. Finally during
the return travel of the movable steps 20, 21, 22 into their initial position shown
at Figure 1, an undulatory motion is imparted to the mass of coal, whilst how-
ever leaving a very uniform or regular incandescent surface for the period of
rest which is about to commence. Again after an inactive period, and an indeter
minate time, engagement will take place anew between the cone 44 (Figure 6) with
the cavity 47, and in the same manner as hereinbefore described. The upper
surface of each series of fixed bars serves as a horizontal support for all the
longitudinal movements of the movable steps actuated as I have already described,
and their bearing surfaces 88, 89, 90, form one with the transverse and longitudinal
girders. For furnaces of great width and for the purpose of giving more strength
to the general working mechanism, the bars 94, 95, 96, may be subdivided, and
supported by any suitable quadrants. I have referred to the individual cleaning
of the surface of the inclined bars 112. . . (Figures 1, 10, 11) resting on
one hand upon a bar 113, and entering respectively into each hollow or recess
formed in the lower heel piece of 112 in the fixed bar 114. For this purpose
I employ a toothed rack 115 cut in accordance with the spaces and the thicknesses
of the cores of the said bars 112. This rack 115 is provided with two right-
angled pieces 116, 117, fixed at a certain distance from one another, in order that
a crank pin 118 (Figures 10, 11) in describing a complete circular movement shall
be enabled to produce an alternating rectilinear movement of the rack 115, and
consequently produce on the outer surface of the inclined bars 112
the place at which the coal is situated, which has been freshly distributed, a
slight undulatory movement of said metallic surface, and also a slight shearing
of the combustible fragments which may adhere thereto. This cleaning move-
ment is constantly ensured by the working of a belt not shown in Figure 1,
but which is driven from a pulley keyed on the horizontal shaft 9, and it then
passes over the pulley 119 (Figure 11) for the purpose of rotating the shaft 120,
the bevel pinion 121 and the bevel pinion 122, which is keyed on the end of a
shaft 123 (Figure 1) the other and opposite end of which is provided with a
plate 124, provided with the pin 118. I have stated above that the series of
bars 88, 89, 90, rested upon hollow passages 91, 92, 93 and I utilise them for the
purpose of collecting from the outside air at the surrounding temperature with
the object of conveying said air by means of said channels connected together to
the vertical tube 125 (Figure 1) and for the purpose of delivering said air,
whose temperature has been raised, into a chamber 126, situated near the hopper 7
formed by refractory bricks and slabs perforated with holes 127
valumes of air collected in this manner pass successively into the furnace
in the middle or at the upper part of the gaseous mixture, and from the very
beginning of the commencement of the combustion of the coal. Whilst another
volume of air which has been taken externally at 128, follows the passage 129
and arrives in the cylinder 130 (Figure 1) and is guided by the tongue 131
below the first movable step 20. The result is that the temperature of the
volumes of atmospheric air that have entered will be inappreciably raised, and
will facilitate their intimate mixture with the gases produced during the com-
bustion. At the lower part of the furnace, closed by the ground line 132, and
at the end of the last section of the grate, a vertical movable plate 133 con-
stitutes the bottom of the lower part of the ash-pit. By means of a longitudinal
hinge 134, I am able by means of a chain to vary the angle of inclination of 133.
Near the plate 133 there is arranged a movable horizontal grate section 135, upon
which all the non-combustible residues which have been pushed from step to
step as hereinbefore described, fall upon this flat surface of 135, and towards
evening the stoker tips it upon its axle 1836 by seizing and moving a hand-
lever 137 (Figure 1) arranged suitably at the outside of the furnace in such a
manner that when the horizontal bar 138 is pushed back, it moves with it the small
rod 139. On releasing the lever 137 of the bar 138, the horizontal grate 135
returns to its original position shown in Figure 1.
These

page_text: 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 furnace with alternating charging, and automatic supply of fuel, the
arrangement of a shaft 9 which serves to rotate intermittently the eccentric 58,
having a groove 59, operating the rod 13, as well as rotating the crank 83 and
its crank pin 84, which operates the lever 14 formed in one with the mechanism
that actuates the movable steps 20, 21, 22, arranged straight or inclined (Figure 1)
moving the fuel from step to step, whilst the movement is effected automatically
and successively through the medium of a gun-metal sleeve 27, which is provided
with a left-hand screw thread and with a right-hand screw thread (the latter
being a continuation of the former) and mounted upon a shaft 9, as described
and shown, and for the purpose specified.
(2) In a furnace having alternating charging and automatic feeding of the
fuel, the arrangement of the shaft 9 and of the gun metal sleeve 27 in combination
with two toothed cones 44, 79; one 44, entering alternately and periodically
in a cavity 47 for the purpose of pushing back the cylindrical periphery of
47, which slides along a key 71 forming one piece with the drum 70 in order to
move it along in a rotary manner, and the other 79 entering during the cleaning
period into the cavity 80 for the purpose of moving the drum 80, the pinion 77
and the wheel 78, as described and shown and for the purpose specified.
(3) In a furnace with alternating feed and automatic supply of fuel, the
arrangement of the shaft 9, of the gun metal sleeve 27, of the cones 44, 79, with
the object of utilising alternately and periodically the rotary action of the
eccentric 58 having a groove 59 for the purpose of raising successively the rod 13,
formed in one with the lever 54 whose boss provided with a pawl 61 causes the
shaft 63 and its blades 64, 65, 66, 67 to oscillate through a determined angle,
with the object of throwing on to the front part of the furnace a quantity of fresh
fuel, whose volume varies in accordance with the size of the aperture lift by the
position of the plate 53, as described and shown and for the purpose specified.
(4) In a furnace with alternating charging and automatic supply of fuel, the
arrangement of the shaft 9, of the gun metal sleeve 27, of the cones 47, 49, with
the object of utilising alternately and periodically, after the period described
in Claim 3, the rotary action of the toothed pinion 78 which drives the gear
wheel 78 keyed on the second shaft 37 parallel to the shaft 9, and provided on
the end opposite 78, with a crank 83, with crank pin 84 for the purpose of causing
the oscillation of the lever 14, formed in one with the mechanism for operat-
ing the movable steps 20, 21, 22, as described and shown and for the purpose
specified.
(5) In a furnace with alternating feed and automatic supply of fuel, the
arrangement consisting in utilising the angular movement of the shaft 15 by means
of the lever 14 for the purpose of producing the ascending motion of the movable
steps 20, 21, 22, by the action of the cranks 16, 17, and their connecting rods 18, 19,
pushing the bars 99, 100 and consequently the arms of the movable steps 20, 21, 22,
as described and shown, and for the purpose specified.
T-11
L
Y
די
1000
ROBERT E. PHILLIPS, Assoc. M.Inst.C.E., M.I.Mech. E.,
Chartered Patent Agent,
70, Chancery Lane, London, W.C., Associate Agent.