Improvements in Fire-grates for Marine Boiler or other Furnaces.
Year: 1888

page_text: Date of Application, 20th Nov., 1888
Complete Specification Left, 16th Aug.. 1889-Accepted, 12th Oct.. 1889
PROVISIONAL SPECIFICATION.
Improvements in Fire-grates for Marine Boiler or other Furnaces.
I, DONALD BARNS MORISON, of 8 Albion Terrace, Hartlepool, in the County of
Durham, Engineer, do hereby declare the nature of this invention to be as
follows:-
My Invention relates to that class of firebars which are moved or agitated either
continuously or periodically, thus keeping the air-passages hetween the bars free from
ashes and clinker and so obtaining more efficient combustion in the furnace.
In applying my invention to marine boiler furnaces, the bars may be in one or
more lengths; but are preferably in two lengths, so arranged that some of the bars
are fixed and the rest are moveable. For instance every alternate bar may be a
fixed bar. These fixed bars are supported at the deadplate, and bridge, at the front
and back of the furnace respectively, and in the middle of the furnace are supported
by a bearer in such a manner that they can be removed or replaced when necessary;
but they do not move with the moveable bars. The moveable bars are supported at
the front and back of the furnace by fixed bearers and near the middle of the
furnace by two bearers so arranged that an up-and-down motion as well as a longi-
tudinal motion is imparted to the moveable bars by suitable levers and rods worked
preferably from the mouth of the furnace.
From the above description it will be seen that ashes in the fire are easily shaken
down into the ashpit, and any clinker forming on the bars, is separated by the motion
of the apparatus hereinbefore described.
COMPLETE SPECIFICATION.
Improvements in Fire-grates for Marine Boiler or other Furnaces.
I, DONALD BARNS MORISON, of .8 Albion Terrace, Hartlepool, in the County of
Durham, 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 :-
My invention relates to that class of fire-grates in which the fire-bars are moved
or agitated either continuously or periodically, for keeping the air passages between
the bars free from ashes and clinker and so obtaining more efficient combustion in
the furnace.
In applying my invention to marine boiler furnaces, the fire bars may be in one :
or more lengths; they may advantageously be in two lengths, so arranged that
some of the bars are fixed and the remainder movable. For instance, every alternate
bar may be a fixed bar. These fixed bars are supported at the dead-plate and the
bridge, at the front and back of the furnace respectively, and in the middle of the
furnace are supported by a bearer in such a manner that they can be removed or
replaced when necessary, but so as not to move with the movable bars. The movable
bars are supported at the front and back of the furnace by fixed bearers, and near the
middle of the furnace are supported by two bearers so arranged and operated that
an up and down motion, as well as a longitudinal motion is imparted to the movable
bars by suitable levers and rods, worked preferably from the mouth of the
furnace.
From the above description it will be seen that ashes in the fire are easily shaken
down into the ash-pit, and any clinker forming on the bars will be separated by the
motion of the apparatus herein before described.

page_text: In the accompanying two sheets of illustrative drawings,
Figs. 1 & 2 are respectively a sectional elevation and a sectional plan of a
boiler furnace having a fire grate according to this invention.
Fig. 3 is a cross section; and
Fig. 4 a front elevation of the furnace.
Figs. 5, 6 & 7 are respectively a side elevation, a plan, and a cross section of one
of the movable fire bars.
There are in the
Figs. 8, 9 & 10 are similar views to Figs. 5, 6 & 7 of one of the fixed fire bars.
Figs. 11 to 14 inclusive are detail views hereinafter referred to.
1, 1ª are the fixed fire-bars, and 2, 2 the movable fire-bars.
example shewn two sets of each viz., a front set and a back set. The front fixed
bars 1 are in line with the back movable bars 2" and the back fixed bars 1 are in
line with the front movable bars 2. A bracket or bearer 3 carried by the dead
plate 4, supports the front ends of the front bars 1 & 2; a similar bracket or
bearer 5 carried by the bridge 6, supports the rear ends of the back bars 1ª, 2ª.
The back ends of the fixed bars 1 and the front ends of the fixed bars 1 are recessed
as shewn in Fig. 8, so that they may be readily applied to and removed from a
transverse bar 7 by which these ends are supported. The bar 7 is carried in brackets 8
(Figs. 11 and 12) fixed to the respective sides of the furnace flue. At these recessed
ends the fixed fire bars are formed, each with a lug or projection 9 as shewn in
Fig. 8, that takes below the transverse bar 7 and prevents rising movement of an
adjacent movable fire bar being communicated to the fixed fire bar by clinker adhering
to both fire-bars, or by ashes wedged between them; 10 is a rod that supports the
recessed rear ends of the front movable fire bars 2 (Fig. 5) and 11 is another rod
that supports the recessed front ends of the rear movable fire-bars 2*. These rods
are carried by levers 12 (Figs. 13 & 14) fixed upon a rock shaft 13 carried by the
brackets 8. To the rod 10 is jointed one end of a rod 14 the other end of which is
jointed to one arm 15 of a bell crank lever, to the other arm 16 of which can be
applied a removable hollow rod or handle 17. By raising and lowering this hollow
rod or handle, the levers 15 and 12 and shaft 13 will be rocked, and an up and down
motion as well as a to and fro longitudinal motion will be imparted to both sets of
movable fire-bars 2, 25. To ensure that the movable fire-bars shall be left at their
normal level after being operated, the hollow rod or handle 17 may be formed with a
collar 18 as shewn, and work in a slot 19 formed in a guard plate 20 carried by the
dead plate, the central part of the opening or slot being enlarged as shown in Fig. 4
and of a size and form corresponding with the collar 18, whilst the top and bottom
portions of the slot are narrower. By this arrangement it will be seen that the
hollow rod or handle 17 cannot be removed from the bent lever 15-16 unless the
collar 18 is in line with the enlarged part of the slot 19, when the fire-bars will be at
their normal level as shewn.
As will be obvious instead of operating the movable fire-bars periodically by means
of a handle such as 17, the lever 15-16 may be operated mechanically by any
suitable means, such as a crank and connecting rod, either periodically or continuously
as desired.
Having now particularly described and ascertained the nature of the said inven-
tion and in what manner the same is to be performed I declare that what I
claim is :-
1. A fire grate comprising (a) movable bars supported and operated in such a
manner that an up-and-down as well as a longitudinal motion (either continuous or
intermittent) can be imparted to them by suitable mechanism as set forth, and (b)
fixed bars supported in such a manner that they can be removed and replaced when
necessary but which are prevented from moving with the movable bars substantially
as described and illustrated.
2. In a fire-grate such as referred to in the preceding claim, the arrangement of
fixed and movable fire-bars in line longitudinally with one another substantially as
hereinbefore described and illustrated.

page_text: 3. My improved fire grate with fixed fire bars, movable fire-bars, and mechanism
for actuating the same, as hereinabove described and illustrated.
Dated this 29th day of July 1889.
W. Lloyd Wise,
46, Lincoln's Inn Fields, London, W.C., Agent for the Applicant.