AN IMPROVED METHOD OF MOUNTING AND GIVING MOTION TO FIRE-BARS
Year: 1860

page_text: alternately producing an oscillating or shaking motion, which causes the ashes
and clinkers to fall through between the bars, thereby clearing the furnace, and
promoting the combustion of the fuel. When it is not required to give motion
to the fire-bars, the cam shaft is secured by a detent.
SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said William Arena Martin and James Purdie in the Great Scal
Patent Office on the 22nd March 1861.
TO ALL TO WHOM THESE PRESENTS SHALL COME, we, WILLIAM
ARENA MARTIN and JAMES PURDIE, of Old Barge House Wharf, Upper
Ground Street, in the County of Surrey, Engineers, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Twenty-eighth day of September, in the year of
our Lord One thousand eight hundred and sixty, in the twenty-fourth year of
Her reign, did, for Herself, Her heirs and successors, give and grant unto us,
the said William Arena Martin and James Purdie, Her special licence, that
we, the said William Arena Martin and James Purdie, our executors, admi-
nistrators, and assigns, or such others as we, the said William Arena Martin
and James Purdie, our executors, administrators, and assigns, should at any
time agree with, and no others, from time to time and at all times thereafter
during the term therein expressed, should and lawfully might make, use,
exercise, and vend, within the United Kingdom of Great Britain and Ireland,
the Channel Islands, and Isle of Man, an Invention for "AN IMPROVED
METHOD OF MOUNTING AND GIVING MOTION TO FIRE-BARS," upon the condition
(amongst others) that we, the said William Arena Martin and James
Purdie, our executors or administrators, by an instrument in writing under
our or their hands and seals, or under the hand and seal of one of us or
them, should particularly describe and ascertain the nature of the said Inven-
tion, and in what manner the same was to be performed, and cause the same
to be filed in the Great Seal Patent Office within six calendar months next
and immediately after the date of the said Letters Patent.
NOW KNOW YE, that I, the said William Arena Martin, on behalf of
myself and the said James Purdie, do hereby declare the nature of the said
Invention, and in what manner the same is to be performed, to be particularly
described and ascertained in and by the following statement thereof, that is
to say:-
This improvement consists in a method of giving motion to the fire-bars of

page_text: LETTERS PATENT to William Arena Martin and James Purdie, of Old
Barge House Wharf, Upper Ground Street, in the County of Surrey,
Engineers, for the Invention of "AN IMPROVED METHOD OF MOUNTING AND
GIVING MOTION TO FIRE-BARS,"
Sealed the 25th January 1861, and dated the 28th September 1860.
PROVISIONAL SPECIFICATION left by the said William Arena Martin.
and James Purdie at the Office of the Commissioners of Patents, with
their Petition, on the 28th September 1860.
We, WILLIAM ARENA MARTIN and JAMES PURDIE, of Old Barge House
Wharf, Upper Ground Street, in the County of Surrey, Engineers, do hereby
declare the nature of the said Invention for "AN IMPROVED METHOD OF
MOUNTING AND GIVING MOTION TO FIRE-BARS," to be as follows:-
This improvement consists in a method of giving motion to the fire-bars of
marine and other furnaces, for the purpose of clearing them from ashes and
clinkers. For this purpose the fire-bars are supported at or near their centres
in such a manner as to be capable of rising and falling when acted upon by.
suitable cams or levers. Beneath the front end of the bars a horizontal shaft
carries a series of moveable cams, which project alternately backward and:
forward. From each of these cams a connecting rod passes up to the under
side of the fire-bar above it. On giving a rocking motion to the cams by
means of a lever handle, the ends of each of the fire-bars rises and falls,

page_text: marine and other steam-boiler furnaces, for the purpose of clearing them from
ashes and clinkers. For this purpose the fire-bars are supported at or near
their centres in such a manner as to be capable of rising and falling when
acted upon by suitable cams or levers. Beneath the front end of the bars a
horizontal shaft carries a series of moveable cams, which project alternately
backward and forward. From each of these cams a connecting rod or link
passes up to the under side of the fire-bar above it. On giving a rocking
motion to the cams by means of a lever handle, the ends of each of the fire-
bars rises and falls alternately, producing an oscillating or shaking motion,
which causes the ashes and clinkers to fall through between the bars, thereby
clearing the furnace, and promoting the combustion of the fuel. When it is
not required to give motion to the fire-bars, the cam shaft is secured by a
detent.
And in order that the manner of performing this our Invention may be
more clearly understood, reference is had to the Drawings hereunto annexed,
and to the following description thereof. The same letters refer to similar
parts in each of the Drawings.
Figure 1 is a side elevation of four fire-bars mounted and arranged agreeably
to our said improvement. A, A, are the fire-bars, supported and moving
freely upon a transverse bearer B. Underneath the dead plate of the furnace P
is placed a longitudinal shaft S, carrying the cams c, c', which are inclined
alternately backward and forward, each cam being attached to the end of
its corresponding fire-bar by a link d. A socket E receives a lever or
handle H, the moving of which up and down gives a rocking motion to the
bars, the ends of which rise and fall alternately. This motion of the fire-bars
breaks up and displaces any clinkers that may have formed upon them, and
also causes the dust and ashes to fall through between the bars, effectually
clearing the furnace, and promoting the combustion of the fuel.
In Figure 1 the fire-bars are shewn at rest; Figure 2 shews them in the
act of rocking; Figure 3 is an enlarged plan view of the cam shaft and the
rocking lever. When the fire-bars are only of a moderate length, we prefer
to support them at or near their centres, as shewn at Figures 1 and 2; but if
the bars are of great length (as is sometimes the case) we support them nearer
to the back end, as shewn in Figure 4. We find the form of fire-bar shewn
in these Drawings to answer very well,, but we do not confine ourselves to this
or any other form of bar, as our improved method of mounting and giving
motion may be advantageously applied to bars of various descriptions. And,
although we have shewn and described a method of giving motion to the bars
by hand, and in general prefer to use that arrangement, yet the same may be

page_text: done by the steam engine if required. Revolving cranks may also be used,
instead of vibrating cams, if preferred.
In order to prevent the bars from moving when not required to do so, we
apply a detent to the cam shaft or to the bars in any way that may be most
suitable in each particular case.
We desire it to be understood that what we claim as our Invention is, the
improved method of mounting and giving motion to fire-bars, substantially as
herein-before described and shewn in the annexed Drawings.
In witness whereof, I, the said William Arena Martin, have hereunto
set my hand and seal, this Twentieth day of March, in the year of our
Lord One thousand eight hundred and sixty-one.
WILLIAM ARENA MARTIN. (L.S.)