A CERTAIN IMPROVEMENT IN STEAM ENGINES
Year: 1852

page_text: TO ALL TO WHOM THESE PRESENTS SHALL COME, I, ROBERT BURN,
of Edinburgh, Scotland, Practical Engineer, send greeting.
WHEREAS Her present most Gracious Majesty Queen Victoria, by Her
Letters Patent bearing date the Twenty-first day of December, A.D. One
thousand eight hundred and fifty-two, in the sixteenth year of Her reign,
did, for Herself, Her heirs and successors, give and grant unto me, the said
Robert Burn, Her especial license that I, the said Robert Burn, my exors,
adñiors, and assigns, or such others as I, the said Robert Burn, my exors,
aditiors, 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 the Isle of
Man, an Invention for "A CERTAIN IMPROVEMENT IN STEAM ENGINES,"
upon the
condition (amongst others) that I, the said Robert Burn, by an instrument
in writing under my hand and seal, should particularly describe and ascertain
the nature of the said Invention, and in what manner the same was to be per-
formed, and cause the same to be enrolled in Her Majesty's High Court of
Chancery within six calendar months next and immediately after the date
of the said Letters Patent.
NOW KNOW YE, that I, the said Robert Burn, do hereby declare the
nature of my said Invention, and in what manner the same is to be performed,
to be particularly described and ascertained in and by the following statement
(that is to say):

page_text: 1
My Invention of "A certain Improvement in Steam Engines," is intended
to reduce friction in the working of such engines, and to economize space, with
other advantages, by means of certain mechanism, hereinafter described,
adapted and applied thereto for the purpose of conveying the motion of the
piston rod to the connecting rod of the crank, in substitution for the mechanism
ordinarily employed for the same purpose.
The mechanism to be so adapted and applied consists of cross heads and
side rods connected at one end with the piston rod, and at the other end with
the connecting rod of the crank, so that the motion of the piston rod may be
transmitted through the mechanism to the connecting rod of the crank. And
the mechanism is so constituted and arranged that the motion from the piston
rod may be thus transmitted or communicated without the use or intervention
of as many guides and sources of friction as have been ordinarily required.
The piston rod passes through, and is keyed or otherwise secured to, one of the
cross heads, which is connected to the other by means of side rods bolted
thereto. These side rods are thus made to act in a parallel line with the.
piston rod, and the connecting rod of the crank may be conveniently lengthened
so as to reduce friction and angular strain in its working.
In order, however, that my Invention may be fully understood, I proceed to
describe more particularly, by the aid of the accompanying Drawing, the
general form and arrangement of the aforesaid mechanism.
DESCRIPTION OF DRAWING.
As my Invention is applicable to various forms of engines, I have thought
it desirable, not. to represent its application to any particular form of engine
complete, but have appended to these Presents merely a Diagram, representing
so much of an engine as is necessary to convey to the mind of the competent
workman an accurate idea of the mechanism, and the mode of its application,
which constitute the essential features of my Invention.
The Diagram represents in elevation a steam cylinder a placed horizontally,
from which proceeds a piston rod b, c is a cross head, which the piston rod is
keyed or otherwise secured...d, d,
are
e two side rods bolted, as shewn, to the two
cross heads c; and e, f, is a guide and guide rod bolted or keyed to the cross
head c. g is the connecting rod, h,is the crank, and i is the excentric and
valve rod.
It will thus be seen that the vertical or horizontal motion of the piston
rod 6 will be transmitted through the cross heads and side rods to the con-
necting rod crank g and fly wheel h, h, the parts of the intermediate mechanism
acting in parallel directions. In adapting this mechanism to other forms of

page_text: engines, it will only be necessary to arrange it so as to secure the parallel
action just described, together with the greatest convenient length of con-
necting rod for the crank.
Having thus described the nature of my Invention, and in what manner the
same is to be performed, I would have it understood that I do not claim as of
my Invention any of the parts described separately considered, but only as used
in combination for the purpose described. I would also remark that my In-
vention is not confined as to its applicability to any particular form of engine,
although it may be more advantageously used in some forms of engines than in
others; for example, those in which the cylinder is placed vertically, and the
piston rod moves in that direction. But what I claim as of my Invention is,
the mechanism, consisting of cross heads and side rods adapted and applied
so as to form an intermediate means of conveying or transmitting the motion
of the piston rod to the connecting rod of the crank, as described.
In witness whereof, I, the said Robert Burn, have hereunto set my
hand and seal, the Eighteenth day of June, in the year of our Lord
One thousand eight hundred and fifty-three.
ROBERT (L.s.) BURN.