Year: 1897

page_text: I, JOHN OWDEN O'BRIEN, M.I. Mech. E., of the Firm of W. P. Thompson & Co.,
of 6, Bank Street, Manchester, Liverpool and London, in the Counties of Lancaster
and Middlesex respectively, Patent Agents, (a communication from Edouard
Poillon, of 7, Rue le Roux a Amiens, in the Republic of France,) do hereby declare
the nature of this invention to be as follows:-
This invention relates to fire-bars and is designed to ensure automatically a
brisk agitation and a thorough admixture of the combustible gases and the air to
support combustion as they pass through the bars, thus realising the complete
combustion of these gases in the fire.
It consists essentially in constructing a grate in which the air passages are
placed or directed obliquely to the surface of the bars and arranged in groups in
alternately diverging and converging directions by which means the air currents
passing through them are compelled to cross each other and thus become thoroughly
mixed with the combustible gases.
The invention also comprises means of rendering efficient the action of the
inclined air passages of the grate and of constructing the grate in a simple and
cconomical manner, as will be explained in detail below.
In carrying my invention into practical effect I prefer to make the grate of
cast-iron plates each having a certain number of slits or air passages inclined in
the same direction and which are very wide at the bottom, so as to afford easy
ingress to the air, and very narrow at the top, so that the currents of air which
issue from these passages move with sufficient velocity to preserve their inclined
direction after they have passed through the layer of coal resting on the grate.
These results are obtained by making these slits or passages of a marked triangular
section.
When a horizontal draught is required, I arrange the plates transversely to the
fire box, the ends being supported on blocks or bars placed lengthwise, and I
place these plates in the required direction so that the air currents from the front
plates are directed towards the bridge whilst, on the other hand, the air currents
coming from the back plates of the fire box issue in the opposite direction.
It will be understood that by this means the intercrossing of the currents of air
issuing from the slits causes a quick agitation of the ignited gases thus ensuring
their complete combustion. This arrangement, moreover, possesses this impor-
tant advantage it absolutely prevents the formation of vertical gas jets called pipe
jets (jets de chalumeau) which cause unequal combustion on the bars, and fre-
quently bring about boiler explosions.
When the draught is vertical, as for instance, when it is intended to heat a
vertical boiler, the plates are placed lengthwise of the grate, that is to say in the
usual manner, care being taken to alternate the direction in which they are placed,
so that the currents issuing from one plate will cross the currents issuing from

page_text: the next plate, thus producing the whirling of the gases in ignition and ensuring
the same results, which have been confirmed by experience.
When the chimney draught is strong, the system works without any special
arrangement, but if the contrary is the case, it is advisable to make use of a forced
draught.
A forced draught may be obtained by closing the ash box, by means of a plate
in which are fitted the pieces in the centre of which are placed the steam jets,
branching from an ordinary conduit or pipe fitted with a regulating tap.
Any other suitable arrangement may also be used for causing a sufficient excess
of pressure in the ash box to impart to the air issuing from the slits in the grate
the high degree of speed which is requisite in order to obtain the result desired.
I have stated that I prefer to use plates with oblique slits for the passage of the
air to promote combustion and experience has proved that the plates in this case
do not get overheated; that the clinker does not adhere to the plates and stop up
the narrow passages intended for the exit of the air, but inclined bars placed close
together may also be used care being taken that they are of exact calibre, so as to
make thin and regular currents of injected air which are requisite for the purpose
in view and these bars should be placed in groups in opposite directions as
described above.
T1
80
WM. P. THOMPSON & Co.,
6, Bank Street, Manchester, Patent Agents.
Improvements in Fire-pars.
I, JOIN OWDEN O'BRIEN, M.I. Mech. E., of the Firm of W.P. Thompson & Co.,
of 6, Bank Street, Manchester, Liverpool and London, in the Counties of Lancaster
and Middlesex respectively, Patent Agents, (a communication from Edouard
Poillon, of 7, Rue le Roux a Amiens, in the Republic of France,) 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 fire-grates and is designed to ensure automatically a
brisk agitation and a thorough admixture of the combustible gases and the air to
support combustion as they pass through the bars, thus realising the complete
combustion of these gases in the fire.
In consists essentially in constructing a grate in which the air passages are
placed or directed obliquely to the surface of the bars and arranged in groups in
alternately diverging and converging directions by which means the air currents
passing through them are compelled to cross each other and thus become thoroughly
mixed with the combustible gases.
The invention also comprises means of rendering efficient the action of the
inclined air passages of the grate and of constructing the grate in a simple and
economical manner as will be explained in detail below.
The invention is fully described hereinafter and is illustrated in the accompany-
ing drawings in which
Fig. 1, is a sectional view of the fire bars or plates on an enlarged scale.
Fig. 2, is a sectional view of a fire-box with the ash-box closed and steam jets.
Fig. 3 is a plan of the fire grate with a part in which the grate is removed.
Fig. 4 is a plan of another arrangement of fire bars or plates in a cylindrical
fire-box.
TA E 11:1
seation on line
of Tio A

page_text: Fig. 6, transverse section on line Y Y of Fig. 4.
In carrying my invention into practical effect I prefer to make the grate of
plates or fire-bars as A (Fig. 1) each having a certain number of slits or air
passages a inclined in the same direction and which are very wide at the bottom,
so as to afford easy ingress to the air, and very narrow at the top, so that the
currents of air which issue from these passages move with sufficient velocity to
preserve their inclined directions through the layer of coal resting on the grate.
These results are obtained by making these slits or passages of a marked trape-
zoidal section in such manner that the axis of the trapezoidal sections be inclined
on the surface of the grate.
When a horizontal draught is required, I arrange as shown in Figs. 2 and 3,
the plates A A¹ transversely to the fire box, the ends being supported in blocks
or bars B placed lengthwise, and I place these plates or fire bars in the required
direction so that the air currents from the front plates or fire bars A are directed
towards the bridge C whilst on the other hand the air currents coming from the
back plates or fire bars A¹ of the fire box issue in the opposite direction.
It will be understood that by this means the inter-crossing of the currents
issuing from the slits a a¹ causes a quick agitation of the ignited gases, thus
ensuring their complete combustion. This arrangement, moreover, possesses this
important advantage, it absolutely prevents the formation of vertical gas jets
called pipe-jets (jets de chalumeau) which frequently cause damage to the boiler.
When the draught is vertical, as for instance when it is intended to heat a
vertical boiler, the plates or fire bars may be placed lengthwise of the grate, that is
to say in the usual manner, care being taken to alternate the direction in which
they are placed so that the currents issuing from one series of plate or fire bars
will cross the currents issuing from the next series of plate or fire bars thus pro-
ducing the whirling of the gases in ignition and ensuring the same results which
have been confirmed by experience. This arrangement is not shown on the draw-.
ings.
When the chimney draught is strong, the system works without any special
arrangement, but if the contrary is the case, it is advisable to make use of a forced
draught.
A forced draught may be obtained by, (as shown in Figs. 2 and 3,) closing the
ash box D, by means of a plate E in which are fitted the tubes F in the centre of
which are placed the steam jets f branching from an ordinary conduit or pipe g
fitted with a regulating tap h.
Any other suitable arrangement may also be used for causing a sufficient excess
of pressure in the ash box to impart to the air issuing from the slits in the grate
the high degree of speed which is requisite in order to obtain the result desired.
In certain cases it may be useful that the flames should cross each other in four
different directions and an application with this object may be made advan-
tageously for example in the interior cylindrical or conical fire grates as is shown
in Figures 4, 5, 6.
It is seen in Figure 4 that four series of plates or bars are employed, A, A1, A³ A³
the directions of the slits or currents of air being different in each series. Figure 5
which is a sectional view on line X X of Figure 4 shows that the plates or bars A A¹
are placed transversely to the length of the fire-grate and that the slits or air-
passages of the plates or bars A have their directions in such a way as to incline
the flames towards the bridge, whilst the slits of the plates or bars A¹ are directed
in such a way as to incline the flames towards the front. On the other hand
the Figure 6 which is a transverse section on line Y Y of Figure 4 shows that the
plates or bars A3 A³ fixed on the sides of the fire-grate are placed parallel to the
length of the fire-grate. The inclinations of the slits of the plates or bars A' are
in an opposite direction to the slits of the plates or bars A³ and these inclinations
are such that they direct the flames towards the middle of the fire-grate. It is
seen by this arrangement chosen after the form of the roof of the fire-grate that
a strong agitation of the gases is obtained at the sides of the grate which makes the

page_text: combustion of the carbon therein more complete than at the sides of the ordinary
grates where the flames spread themselves out against the adjoining walls of the
opposite sides of the grate.
It will be understood that I can combine in different ways the arrangement of
the series of plates or bars in the fire-grates in such a fashion as to give to the
flames different directions appropriate to the conformation of the roofs of the fire
grates, in such a way as to divide reasonably the action of the flames on the plates
and at the same time effect a strong agitation of the gas.
Having now particularly described and ascertained the nature of the said
invention and in what manner the same is to be performed, I declare that what
I claim is:-
1. A grate formed with plates or fire bars having slits or air passages of trape-
zoidal section, very wide at the bottom, and very narrow at the top; the axis of
these air passages or slits being directed obliquely to the surface of the grate and
inclined toward the bridge.
2. A grate formed with plates or fire bars having slits or air passages of trape-
zoidal section very wide at the bottom and very narrow at the top; the axis of
these air passages or slits being directed obliquely to the surface of the grate
and inclined towards the bridge the said plate or fire bars being placed at the
front of the fire box in combination with back plates or fire bars having the axis
of slits or air passages inclined towards the front of the fire box.
3. In fire boxes in which the draught is vertical-a grate formed with plates
or fire bars made as hereinbefore described and placed lengthwise or transversely
of the fire box and alternated in such a manner that the direction of the axis of
the slits or air passages of one series of fire bars cross the direction of axis of slits
or air passages of another series.
4. In cylindrical or conical fire grates a grate formed with the plates or bars
having slits or air passages of trapezoidal section very wide at the bottom and
very narrow at the top; the axis of these air passages or slits being directed
obliquely to the surface of the grate; a series of the said plates or bars being
placed at the front of the fire grate and occupying the part of the centre in which
the slits are inclined in such a way that the flames may be directed towards the
bridge, another series of the said plates or bars being placed behind the grate and
occupying the middle of the grate and in which the slits are inclined in such a
way that the flames may be directed towards the front of the fire grate in com-
bination with plates or bars placed at the sides of the fire grate and in which
the slits are inclined in such a way as to direct the flames towards the middle of the
fire grate.
5. In the fire grates of various forms the combination of series of plates or bars
in such a way that the slits or air passages incline the flames in the directions
appropriate to the special form of fire grates.
6. The arrangements or combinations of fire grates applied either with natural
draught or with draught forced by air or by steam substantially as described and
shown.
1
10
Το τ ΤΙΣ ΤΟ
STO
1000
WM. P. THOMPSON & Co.,
Manchester, Liverpool, & London, Patent Agents."