Improved Furnace Grate with Automatic Feeding Contrivance.
Year: 1898

page_text: Date of Application, 24th Dec., 1898-Accepted, 25th Mar., 1899
Improved Furnace Grate with Automatic Feeding Contrivance.
I, ALBERT FROUVÉ, of 91, Boulevard de Courcelles, Paris, in the Republic of
France, 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
-
This invention relates to a new furnace grate arrangement, with movable bais,
fed with coal in a gianular form, or in pieces, by means of an automatic feeding
contrivance,
It consists in a grate made with specially constructed bars, which can be pushed
backwards or forwards, and slightly raised at the same time, in order to dis-
integrate the cinders or clinkers, the said grate which is suitably inclined, and
more or less open at the end above the ash pit, being fed with coal by means
of an automatic feeding contrivance, supplying vanable quantities
In the accompanying diawings,
Fig 1 is a side elevation and vertical section,
Fig 2 a plan view and horizontal section,
Figa 3 and 4 ai vertical section, and side elevation respectively of one of the
cams which impart the forward and backward motion to the bars
Figs 5 and 6 are cross sections, between two bais and perpendicularly to the
shaft caving the cams, showing the mounting and the form of one of the cains,
as well as the manner in which it acts on a bar
It 18
The feed hopper A, with a contracted aperture A¹, is placed in front of the
opening of the grate, in place of the ordinary doors, and opens at the bottom, on
to a table B, inclined from the bottom of the opening or mouth of the grate. The
feed hopper 18 open at the top, for the reception of the fuel, with which it 18
always more or less filled. C is a distributing arrangement, placed below the
nariowed opening A and in the lower latrial opening of the hopper in front of the
stoke-hole D 18 the shaft on which the distributing apparatus is mounted
actuated by a fractional intermittent rotary motion, the interval between the
fractions of a rotation being longer or shorter, accordingly as the quantity of fuel
supplied to the grate should be large or smaller. This variation in the speed of
the shaft D can be effected in several ways, in particular, by the employment of
two cones and N, which transmit the motion of the shaft M to the shaft K,
whether the motion of the shaft I be independent of or dependent on that of
the shaft D carrying the cams CC which impart a slow forward and backward
motion to the bars of the grate, at the same time that they are able to convey a
slight upward motion thereto EE are the bars of the giate, preferably made of
and in three parts (1) (2) (3), riveted together, the upper surface of which
18 arranged in a step-like form, or like the teeth of a saw, for diawing the fuel
towards the back FF are the bearers, on which the ends of the bars EE are
supported and can slide. a 18 a recess formed under each interior plate of a bar
between the tappets b and c which at the same time unite the external plates of
a bar, in which, and between the said tappets, the shafts of the cams with cheek
pieces" CC engage. Each cam pushes with its operative end, first one and then
11'on,
"

page_text: the other tappet of a bar, causing the bar to slide alternately to the right and to
the left
The operative part of the cams CC moves in the longitudinal recess in the
interior of each bar, formed by the juxtaposition of three on plates of the same
length and thickness, the middle one, however, which is of rectangular section,
being about half the height only of the other two, the exterior faces of which are
inclined and actuated as shown in Fig 5, the upper part of this rectangular plate
18 on a level with the other two, and beneath, along the whole of the bai, is a space
in which the operative parts of the cams have play, and in this space the two
tappets band, already mentioned, are placed
The cams may be mounted on the shaft which causes them, either on a spindle
common to all or at different angles
It will be seen that if a more or less accelerated motion be communicated to
the staged cone L, the shafts M and I will be simultaneously rotated.
The shaft M actuates the upper pulley 9 by means of the lower pulley N and
the belt O The upper pulley y may have the form of a small conical dium, as
indicated, in order to be capable of slightly varying the rotary speed of the shaft K.
The rotation of the shaft K, which caines the endless sciew V engaging with
the wheel m, mounted on the same shaft H₁ as the small pinion 1, is transmitted,
by means of the intermediate parts indicated, to the pinion keyed to the shaft D
of the distributor C, through the tooth wheel d, which engages with the pinion
and 18 mounted on the shaft H carrying the came which in rotating causes an
oscillation of the lever f, the pawl of which, at each stroke, causes a rotation
of the ratchet wheel g to the extent of a certain number of teeth and consequently
of the tooth wheel h, which engages with the pinion, keyed to the same small
shaft as the wheel, which engages with the pinion alieady mentioned
pinion thus causes the ". wings of the distributor C to turn in the direction
indicated by the arrow, in such a manner that the "wings" convey the coal through
the bottom of the opening in the distributor on to the table B which should be
sufficiently inclined.
39
The
The fuel is thus insensibly pushed towards the head of the giate, to which it
is likewise impelled by the motion of the bais, the upper faces of which are cut
or arranged in step fashion, as shown.
Whilst the distributor C is conveying the coal from the hopper A to the suf-
ficiently inclined table B, the shaft D₁ on which the cams C¹ are mounted 18:
notated, and consequently causes a rotation of all these cams, the operative end of
which now pushing against the projection b, now against the projection ‹, causes
each bay to slide on the bearers, from left to night and inversely. The cams C¹¹
mounted on the shaft D¹ may be so arranged that a bar descends when the two
adjacent ones use, and vice versa The coal is thus conveyed from the head of
the grate, where the gases begin to be given off, to the lowest extremity of the
giate, which it reaches in a used up condition, whilst the cinders etc. pass out by
the opening G through which a supplementary curent of air flows and assists
the combustion in front of the fire-bridge of the last remains of combustible
gases
not vet consumed This opening G may be closed more or less, by means of the
register G mounted on the axis T, which runs through the casing of the furnace
and passes out therefrom, in order that a crank handle which can be fixed in any
desired position, may be attached to one of its ends
If the cams were arranged with different mountings, the bars, instead of moving
all together and in the tame dnection, could move in such a way that, whilst one 5
bai was sliding to the right, the two adjacent bars would slide to the left The
same bars might, again, move so that one would slide in a certain direction whilst
the adjacent bais would slide in the same direction but somewhat more slowly,
producing differential speed motions
In any case, the inclined table B and the bars EE being assumed, as well as s
the manner in which the surface of the bars is formed, the cinders etc are dis-
integrated, the spaces between the bars are always free for the easy passage of the

page_text: air of combustion, which cools the bars and keeps them in good condition, and the
coal is conveyed insensibly and methodically, in a continuous and visible manner,
from the head of the grate to its other and lower extremity, which it reaches in
a used up condition, the rate at which the coal is carried along the grate and the
draught of the chimney being regulated in consequence
It will be seen that, in the new furnace grate arrangement, with movable bars
and automatic feeding contrivance, just described, the cleaning of the grate is
avoided, as well as the formation of any thick smoke and any abnormal return
of air besides all feeding and stoking by the fireman In consequence the duty
of the last mentioned is reduced to that of an intelligent watcher, who may look
after a number of fines at the same time without being fatigued, and with great
advantage as regards economy.
It can be readily imagined that in a fire place arranged as described, where the
file 18 regularly fed with small quantities of fuel which are pushed on to the sur-
face of the grate and spread thereon without becoming caked having the air of
combustion constantly passing through the same, the combustion must be as
complete and as economical as possible, without causing any appreciable quantity
of smoke
This system of furnace grate with automatic feeding contrivance, is thus easy
to carry out, perfectly smoke-consuming, easily regulated and consequently very
economical in working
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 19:―
1 In a furnace giate with movable bars and automatic feeding arrangement,
the bars EE, inclined towards the back, where an opening G is provided for the
cinders etc to pass through and a register G¹ which regulates the passage of air,
each bar being composed of three plates of iron (1) (2) (3), riveted together, but
not in contact, their upper surfaces being cut like the teeth of a saw, and under
each of which bars and between two tappets b and c a cam a has play, this cam
being heved to a shaft D¹ rotating at a greater or less rate of speed, the operative
part of each cam, in coming in turn against the tappets be causing the bars to
slide on their bearers FF first from right to left, then from left to right, the
said bars sliding all together in the same direction
2 In a furnace grate with movable bars and automatic feeding arrangement,
the bars EE inclined towards the back where a hole G is provided for the cinders
etc to run through and a register G₁ regulating the passage of air, each of these
bais being composed of three iron plates (1) (2) (3), riveted together but not in
contact, the upper surfaces being cut like the teeth of a saw, and under each of
which bars and between two tappets b and c a cam C¹ has play, the cam being keyed
to a shaft Dotating at a greater or less rate of speed, the operative part of each
cam in coming in turn against the tappets be causing the bars to slide on their
bearers FF fist from right to left then from left to right, the said bars sliding
all together but being further actuated by a slight upward motion, produced by
a sufficient raising of the general axis D¹
3 In a furnace grate with movable bais and automatic feeding contrivance, the
bars EE inclined towards the back where an opening G is provided for the cinders
etc to pass through, and a register G¹ regulating the passage of air, each bar
being composed of three iron plates (1) (2) (3), riveted together but not in contact,
the upper surface being cut like the teeth of a saw, and under each of which bars,
and between the tappets bc, a cam Chas play, such cam being keyed to a shaft D¹,
rotating at a greater or less rate of speed, the operative part of each cam, in coming
in turn, against the tappets bc, causing the bars to slide on the bearers FF,
first from right to left, then from left to 11ght, the said bars sliding all together
in the same direction but with different rates of speed
4 In a furnace giate with movable bars and automatic feeding contrivance, the

page_text: bars EE inclined towards the back, where an opening is provided for the cinders
etc to pass through, and a register G¹ regulating the passage of air, each bar being
composed of three iron plates (1) (2) (3) veted together, but not in contact, the
upper surface being cut like the teeth of a saw, and under each of which bars, and
between two tappets bc, a cam C has play, this cam being keyed to a shaft DI
rotating at a greater or less rate of speed, the operative part of each cam, in coming
in tuin, against the tappets bc, causing the bais to slide on their bearers FF,
first from night to left, then from left to right, the said bais sliding all together
in the came duection but at different rates of speed, and being further actuated by
a slight upward motion produced by a sufficient raising of the shaft D'.
5 furnace grate with movable bais and automatic feeding arrangement, as
specified under Claim 1, but in which the said bais slide some in one duection,
some in the other direction
6 In a furnace grate with movable bats and automatic feeding arrangement, as
specified under Claim 1, in which the said bars slide some in one direction, some
in the other duection, and being given a slight upward motion, produced by a
sufficient raising of the shaft DI
7. In a furnace grate as specified under Claim 1, the open hopper A, with a
contracted aperture A¹, a winged" distributor C actuated by an automatic inter-
mittent rotai v motion, the extent of which is regulated, and a table B sufficiently
inclined, conveying to the head of the grate the fuel delivered by the “winged
distributor C
8 In a furnace grate as specified under Claim 1, the whole motive contrivance,
rendering it possible by means of the two stage cone LNq, simultaneously to
actuate, on the one hand the shaft D' of the cams by means of the pulley p and on
the other hand, the shaft D of the distributor by means of the shaft M, the
pullies Ng which may be of cone shape and the belt 0; the shaft K, the screw V,
engaging with the wheel m keyed on the shaft H', carrying the pinion I, which
engages with the wheel d keyed on the shaft H carrying the cam e rotating on the
arm loaded with the weight e, of the lever f carrying at the extremity fl of its
other arm, a pawl, engaging in the teeth of the ratchet wheel g mounted on the
same axis as the wheel which engages with the pinion 1, mounted on the same
axis as the wheel 1, which finally engages with the pinion k keyed to the shaft D
of the distributor
Dated this 24th day of December 1898.
WHEATLEY & MACKENZIE,
40, Chancery Lane, London, W.C, Agents.