IMPROVEMENTS IN STEAM ENGINES
Year: 1853

page_text: LETTERS PATENT to John Bourne, of Port Glasgow, in the County
of Renfrew, in Scotland, for the Invention of "IMPROVEMENTS IN
STEAM ENGINES."
Sealed the 30th May 1854, and dated the 9th December 1853.
PROVISIONAL SPECIFICATION left by the said John Bourne at the
Office of the Commissioners of Patents, with his Petition, on the
9th December 1858.
I, JOHN BOURNE, of Port Glasgow, in the County of Renfrew, in
Scotland, do hereby declare the nature of the Invention for "IMPROVE-
MENTS IN STEAM ENGINES" to be as follows:-
The design of my improvements in steam engines is to enable them
to move with steadiness at a high rate of speed, and this I accomplish
by balancing the momentum of the reciprocating parts by the applica-
tion of counter weights properly applied. The crank of the engine I
form of two discs of iron, each firmly fixed on its shaft and with the
crank pin extending between them, and I connect firmly the one end
of the crank pin with one disc, and the other end of the crank pin
with the other disc, so that the combination forms a double sided and
perfectly rigid crank, and is as strong as if the whole were cut out of
a single piece of iron. As the crank pin is not overhung there is
none of the twisting action upon it which takes place when the crank

page_text: is made with a single arm, or when the pin is loose in one eye; and the
use of discs instead of ordinary cranks enables an adequate length of
crank pin to be obtained for a high rate of speed without separating
the shaft bearings to an inconvenient extent. The species of engine
which I prefer to use is a horizontal engine somewhat similar to those
used in locomotives, and I apply counter weights to the discs in such a
manner, that when the piston and parts attached to it are moving in
one direction the counter weights are moving in the opposite direction,
and their weight being suitably adjusted to the weight of the recipro-
cating parts, the momentum is balanced, and there is no shock from
arrested momentum even at very high rates of speed. Where a single
engine is employed, the counter weights will also prevent it from stopping
at the end of the stroke, and will bring it to the middle position, from
whence it may be conveniently started in either direction. As in
engines moving at a high rate of speed the lubrication of the crank pin
in the usual manner is inconvenient, I lubricate the crank pin from
the oil boxes of the crankshaft by carrying from thence suitable pipes
to the centre of the pin, the pin being itself perforated to enable the
oil to find its way to the surface of the bearing, and the oil is carried
outward by the centrifugal force, a cock being interposed to regulate
the supply.
To maintain an equable and adequate supply of steam such as
engines working at a high velocity require I employ a fan or fans set
in the stoke hole, and the stoke hole is so made that the doors and
hatches leading into it are kept quite close when the engine is at work,
whereby a pressure of air is kept up in the stoke hole that aids the
combustion of the fire and increases the production of steam.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said John Bourne in the Great Seal Patent Office on
the 2nd June 1854.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I,
JOHN BOURNE, of Port Glasgow, in the County of Renfrew, in Scotland,
send greeting.

page_text: WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Ninth day of December, in the year
of our Lord One thousand eight hundred and fifty-three, in the seven-
teenth year of Her reign, did, for Herself, Her heirs and successors,
give and grant unto me, the said John Bourne, Her special licenco
that I, the said. John Bourne, my executors, administrators, and
assigns, or such others as I, the said John Bourne, my 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 "IMPROVEMENTS IN
STEAM ENGINES," upon the condition (amongst others) that I, the said
John Bourne, 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 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 John Bourne, 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):-
The design of my improvements in steam engines is to enable
them to work in a satisfactory manner at a high rate of speed, and
also to enable them when so working to obtain sufficient steam by
stimulating the combustion by suitable apparatus for that purpose. I
impart steadiness to the movements of engines working at a high
speed, and clear them from shock and tremor. This I accomplish by
balancing the momentum of the reciprocating parts by the application
of counter weights so applied that when the piston and its connexions
aro proceeding in one direction the counter weights shall be proceeding
in the opposite direction. The crank of the engine I form of two
discs, each firmly fixed on its shaft and with the crank pin extending
between them, and I connect the one end of the crank pin with one

page_text: disc, and the other end of the crank pin with the other disc, in so firm
and substantial a manner that the combination forms a double sided
crank of as solid and rigid a construction as if the whole wero cut out of
a single piece. The crank pin is forged with strong flanges upon it near
the ends, which flanges fit into corresponding recesses in the discs, and
strong countersunk bolts pass through the flanges and the discs so as
to connect them firmly together. The ends of the pin also pass
through the discs and are rivetted over in the usual manner. As the
crank pin is not overhung, there is none of the twisting action upon it
which exists when the crank is made with a single arm, or when the
pin is loose in one eye; and the use of metal discs instead of cranks of
the ordinary form enables an adequate length of pin to be obtained for
a high rate of speed without separating the shaft bearings to an incon-
venient extent. The crank pin is both made of unusual thickness and
of unusual length so as to afford a large amount of rubbing surface,
since a large amount of rubbing surface is indispensable to enable
engines to work without heating at a high rate of speed.
.
The species of engine which I prefer to use is a horizontal engine
of the kind represented in the accompanying Drawings; and the
counter weights which I fix upon the discs are applied in such a way
that they not only balance the momentum of the reciprocating parts of
the engine, but assist the engine over the centre, and thus enable a
single engine to be employed in many cases in which the use of two
engines has heretofore been deemed indispensable. One of the prin-
cipal purposes to which I propose to apply my improvements is the
propulsion of screw vessels, and a single engine if made with my
improvements will be sufficient for this purpose, whereas two engines
are now commonly employed. It will be obvious on an inspection of
the accompanying Drawings, that when the cylinder is horizontal and
the counter weights are set in such a position as most effectually to
counteract the momentum, which will be when they are opposite to the
crank pin, the gravitation of the counter weights to the lowest point
of the circle in which they revolve will naturally tend to set the piston
in the middle of its stroke when the engine is stopped, from which
position it may be conveniently started either forward or backward as

page_text: may be required. If, however, the piston should be very tightly
packed, so as to be incapable of moving with freedom in the cylinder,
the gravitation of the counter weights may not be sufficient to bring
the piston to the middle of the stroke with the requisite facility; and
to provide against such a contingency or against other similar faults of
imperfect adjustment, I bore a number of holes near the outer edge
of one of the discs, so as to enable the disc to be pinched round by a
bar of iron, the framing or some other convenient part of the engine
serving as a fulcrum for that purpose.
i
My next improvement consists in a superior method of lubricating
the crank pin of an engine moving at a high rate of speed. Instead of
applying an oil cup upon the crank pin to accomplish its lubrication
as is the usual practice, I lubricate the crank pin with oil or other
lubricating material derived from the oil boxes of the crank shaft by
carrying from those oil boxes suitable pipes to the centre of the pin.
The pin is itself perforated to enable the oil to find its way to the
rubbing surface of the bearing, and the oil which is fed into the oil
boxes of the shaft is carried outward by centrifugal force to the crank
pin, and there distributed over the surfaces to which lubrication has to
be applied. To enable the oil to pass outward to the crank pin the
necks of the shafts intervening between the oil boxes and the discs
must be perforated in the direction of their axes and also radially, and
a hole must be bored, or a pipe cast in, or attached to each of the metal
discs so as to connect the perforations in tho necks of the shafts with
the crank pin. The crank pin likewise must be perforated both in the
direction of its axis and also radially, and the ends of the several holes,
which must be drilled to accomplish the required connexion, but out of
which oil is not required to flow, must be plugged by screws or other-
wise which may be removed at pleasure to enable the passages to be
properly cleaned out. These connexions are shewn in dotted lines in
the transverse section of engine numbered Figure 3, in the accom-
panying Drawings, and by an inspection of this Figure, the nature of
the arrangement for the lubrication of the crank pin will be at once
understood. Instead of lubricating wholly with oil or with some oily
liquid, I sometimes lubricate with water and sometimes with a mixture

page_text: of oil and water, or soap and water, but the liquid whatever it may be
follows in every case the course which has been already described.
I will now proceed to describe more in detail the form of engine
which I employ, and which contains my new improvements; Figure 1,
of the accompanying Drawings, is a vertical longitudinal section of the
engine; Figure 2, is a ground plan; and Figure 3, a transverse section.
The same letters refer to the same parts in all the Figures. A, is the
cylinder; B, the piston; C, the condenser; D, D, the discs which servo
the purpose of a double crank; E, E, the piston rods, there being
two piston rods set diagonally to each piston; F, F, are two rods
forming conjointly the connecting rod; G, the air pump; H, the cross
head which receives motion from the piston rods and communicates it
to the connecting rod; I, I, I, I, the pipes or channels through which
the oil or other lubricating material is conveyed from the shaft oil cups
K, K, to the crank pin U. The ends of the holes in the crank pin
and shaft neck axes are plugged up with removeable screws X, X;
L, is the throttle valve; M, the slide valve which is of the ordinary
three ported description, but to prevent it from being pressed on to the
face of the cylinder with so much force as would render it difficult to
move, it is withdrawn from the face or balanced by the balance piston
N, which is connected to the valve by the link O. A vacuum is
maintained above the balance piston N, by means of a passage leading
to the condenser at P, or if it is judged advisable to increase the
pressure on the valve M, then the pipe or passage P may be opened
to the atmosphere instead of to the condenser; Q, is a four way cock for
heating either end of the cylinder or for starting or moving the engine;
it also serves the purpose of a blow-through valve when pressed back
out of its seat in which it is kept by a spiral spring. R, is a cam for
opening and closing the throttle valve so as to work the engine
expansively. S, is the screw shaft; T, T, are small cranks which are
employed instead of excentrics for working the link motion which is of
the ordinary description; V, is the feed pump; and W, W, are the
counter weights, which are of lead or any other suitable material. These
weights are sunk between ribs cast on the discs and each of them is
secured in addition with three strong counter-sunk bolts. The cross a

page_text: head of the engine moves in guides of the ordinary description, and the
air pump is worked off an arm Y, fixed on the cross head, and to which
also one of the piston rods is attached. To maintain an equable and
adequate supply of steam, such as is especially necessary in the case of
engines working at a high rate of speed; I employ a fan or fans set in
or connected with the stoke hole, and the stoke hole is so contrived
that the doors and hatches communicating with the external atmosphere
are made air-tight by any usual arrangement for that purpose, and
they are kept quite close when the engine is at work, whereby such a
quantity of air passes through the fire that the combustion is accelerated
to the required extent.
Having thus described the nature of my Invention, and the manner
in which the same may be practically applied, I have only to add that
I do not claim the exclusive right to use counter weights in every species
of engine or in whatever manner those counter weights may be applied,
since in locomotive engines counter weights fixed upon the driving
wheels have been long employed to correct the sinuous motion of the
engine on the rails; neither do I claim the exclusive right to use discs
instead of cranks generally in steam engines, since a single disc instead
of a single crank has in many cases been already adopted; but
I claim the exclusive right as being new and of my Invention, to use
double discs connected together by a rigid and inflexible crank pin as
herein-before explained, and I claim the exclusive right to use counter
weights in connection with such discs so as to form a strong unyielding
and counter balancing combination. I also claim the exclusive right to
use the mode of lubricating the crank pin bearing already described.
In witness whereof, I, the said John Bourne, have hereunto set
my hand and seal, this Twenty-sixth day of May, in the year
of our Lord One thousand eight hundred and fifty-four.
Witness,
JAMES CURRIE, of Greenock.
JOHN BOURNE. (LS.)