IMPROVEMENTS IN AND APPERTAINING TO FIRE GRATES
Year: 1883

page_text: LETTERS PATENT to Henry Harington Leigh of the firm of Phillips and
Leigh Engineers and Patent Agents 22 Southampton Buildings Chancery
Lane in the County of Middlesex for an Invention of "IMPROVEMENTS IN
AND APPERTAINING TO FIRE GRATES" communicated to him from abroad by
Société des foyers économiques, Gouiet et Company, of Paris, France
PROVISIONAL SPECIFICATION left by the said Henry Harington Leigh at
the Office of the Commissioners of Patents on the 9th June 1883.
HENRY HARINGTON LEIGH of the firm of Phillips & Leigh Engineers and
Patent Agents 22 Southampton Buildings Chancery Lane in the County of
Middlesex "IMPROVEMENTS IN AND APPERTAINING TO FIRE GRATES [com-
municated to him from abroad by Société des foyers économiques, Goujet et
Company, of Paris, France]
The object of this Invention is to produce a more perfect combustion than has
bitherto been obtained in fire grates owing to the imperfect construction of the
bars, air spaces and other parts.
My invention chiefly relates to a new style of rocking bar and also to a new and
improved lower lateral partition.
My new and improved fire grate produces a more perfect combustion by the use
of my improved rocking bars and by having three of its sides formed with my
improved partitions which have numerous air passages or spaces.
My improved fire grate is composed of several bars in wrought or cast iron
having slots in them for the reception of the divisions on the underside of the bars
and the chairs for carrying the driving shaft which imparts motion to the bars as
will be hereafter explained; the last bar is strengthened in section in order to bear
the back portion.
The bars are of special form that is of an anchor or harpoon shape the central
part is level the upper part is of a conical form and the lower part ends in almost
a point; there are vertical air spaces which penetrate in an upward direction the

page_text: two flukes of the anchor shaped section, the air in passing through these spaces
becomes heated and promotes a more perfect combustion.
According to another modification of my bar I form the end of a circular shape
so that it supports the rocking bar hereafter described the whole of the series of
bars is actuated by a rack and pinion or it may be by a quadrant.
From the driving shaft which is carried outside the fire grate the oscillating
motion is imparted to the fire bars as follows:-to the ordinary pinion I affix a
disc to which is attached a rod gearing into a lever fixed at one end and having
four holes at different distances from the driving shaft which serve to receive the
rod, by this means I can impart the full motion or a portion, to the bars, these
serve to break up the fire and also to prevent the waste of fuel so general in the
ordinary type of fire grate.
The interior partitions which surround the grate on three sides leave only the
front uncovered, are slightly centered and provided with horizontal grooves these
grooves increase the surface of the draught and prevent the coal becoming caked
and blocked, which is so often the case in the present construction of fire grates;
by a number of currents of heated air the abatement of smoke is thereby greatly
effected.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Henry Harington Leigh in the Great Seal Patent Office on the
20th November 1883.
HENRY HARINGTON LEIGH, of the firm of Phillips & Leigh, Engineers and
Patent Agents, 22, Southampton Buildings, Chancery Lane, in the County of
Middlesex "IMPROVEMENTS IN AND APPERTAINING TO FIRE GRATES
" A com-
munication to me from abroad, by Société des Foyers Economiques, Goujet et
Company, of Paris, France,
The object of my invention is to produce a more perfect combustion than has
hitherto been obtained in fire grates, owing to the imperfect construction of the
bars, air spaces, and other parts.
My invention chiefly relates to a new style of rocking bar, and also a new and
improved lower lateral partition. The improvements resulting from its use are,
1st, more perfect combustion in consequence of an improved air supply, due to the
conformation of my improved fire bars and bearers, and method of rocking said
fire bars; and, 2nd, a longer life for the said fire bars, due to my improvement in
the shape of them, which prevents their twisting or bending as readily as fire bars
of the usual shapes do.
In order that my Invention, and the methods I employ in carrying it out, may
be perfectly understood, I append two sheets of drawings illustrative thereof, which
I intend to be taken as part of this specification. Similar letters of reference refer
to similar parts throughout the drawings.
My improved grate is formed of several bearers of either cast or wrought iron, F,
shewn in elevation in Figure 5, and in plan in Figure 9.
There are formed on the upper faces of these bars semi-circular seats f. f, as
shewn in Figure 5, to receive the ends of the grate bars; grooves h³, h³, to receive
the feet of the sides of the furnace, H; and arms, G, through the ends, g, of
which the shaft, n, works, to rock the bars in the way hereinafter described. The
back bearing bar, F¹, shewn in plan in Figure 9, is made extra strong, by having
an additional ridge formed on it as shewn in section in Figure 6, to enable it to
bear the weight of the further side of the furnace, as well as a portion of the
combined weight of the two sides.
In the semicircular seats, f, f, rest the ends e, e, of my improved grate bars, E,
shewn in plan at Figure 1, in elevation at Figure 2, and in section at Figures 3
and 4.
Figure 3 is taken on the dotted line a. b. in Figures 1 and 2, and Figure 4 on
the line c. d. in the same figures. These bars are, as the figures shew, of a special
form, in section closely resembling a double-fluke anchor. The bulky central
portion of the bar is developed upwards as a ridge of a markedly conical section,
and downwards almost to a sharp edge. The wing, or fluke-shaped parts of my
grate bars have formed at their thinnest part a series of longitudinal openings i, i.
The lower edge is, for a portion of its length, expanded into a round moulding, k,
as shewn at Figure 4. All the mouldings of the same set of bars are held
together, as shewn in Figure 7, by a rack K. A series of nearly circular notches, 1, 1,
receives the mouldings, and holds the rack in position. This rack is toothed on
its under side to engage with the pinion, m, carried by the shaft, n.
My improved fire grate is rocked by the shaft, n, which carries, outside the
furnace, a lever, o, Figure 8. When a perpendicular-reciprocating movement is
communicated to this lever, the shaft, n, (and consequently the pinion m keyed
on it), makes a half revolution, now to the left, now to the right. A horizontal-

page_text: reciprocating motion is thus communicated to the rack, K, and a rocking motion to
the fire bars (the ends, e, e, of which rest in the seats f, f.) around the axes of the
mouldings. The conical shape given to the upper part of the grate bars keeps the
bed of fuel broken up, thus effectually preventing caking, Moreover, the air
passing upwards through the openings i, i, and between the bars, reaches the bed
of fuel at a high temperature, and so facilitates combustion.
My improved fire bars are consequently much less liable than the ordinary bar
to get out of shape, inasmuch as the wings or flukes, forined in their sides, prevent
any lateral twisting which the fire might induce in their central portions, and as
the lower part of the central portion of each bar, is held in the rack, K, it cannot
get out of shape in any way.
The degree of maximum or minimum inclination, to be given to the bars during
rocking, is regulated by the adjusting-arrangement shewn in Figure 8. The lever, o,
has four holes formed in it at different distances from the axis of the shaft, n, to
one of which the connecting rod, p, is attached. Its other end is connected to the
These holes are at
revolving disc, q, at one of the four holes formed therein.
unequal distances from the axis of the disc.
My improved furnace sides are shewn in sectional elevation in Figure 5, and in
plan in Figure 9. These sides, which surround the fire grate on three of its sides,
leaving only the front open, are arched a little, and have horizontal grooves, h, h,
formed therein. These grooves increase the draft of the furnace, prevent caking
(which has up to the present time been an inevitable loss), and improve com-
bustion by allowing a considerable number of currents of hot air, crossing each
other, to reach the interior of the furnace.
Having thus described my invention, I would have it understood that what I
claim is
First The improved rocking bar made with a conical, ridge and two fluke-
shaped extensions on its upper side, and with openings for the passage of currents
of air, formed in the thinner portion of said extensions, substantially as and for
the purpose described and illustrated.
Second-The application to rocking bars of a fire grate, of a rack with nearly
circular notches to receive mouldings formed on the bottom edge of the bars, and
serving to support the rack, substantially as and for the purpose described and
illustrated
:
Third In a fire grate with rocking fire bars, the use of an adjustable device for
rocking said bars, consisting of a disc having several holes at unequal distances
from its axis, to anyone of which a connecting rod is fixed, its other end being
bolted to one of the holes in the lever, o, keyed upon the shaft n, which in its
turn carries a pinion m, engaging with the rack Ķ, all substantially as and for the
purpose described and illustrated.
Fourth-The application to the inside of a furnace, of slightly arched sides
forming a three-sided enclosure, said sides having horizontal grooves for currents
of air to pass through, all substantially as and for the purposes described and
illustrated.
In witness whereof I, the said Henry Harington Leigh, have hereunto set my
band and seal this Thirtieth day of October in the year of our Lord, One
thousand eight hundred and eighty three.