IMPROVEMENTS IN STEAM ENGINES AND IN THE COMBUSTION OF FUEL
Year: 1857

page_text: LETTERS PATENT to Alexander Chaplin, of Glasgow, in the County of
Lanark, North Britain, Engineer, for the Invention of "IMPROVEMENTS
IN STEAM ENGINES AND IN THE COMBUSTION OF FUEL."
Sealed the 23rd March 1858, and dated the 26th December 1857.
PROVISIONAL SPECIFICATION left by the said Alexander Chaplin at the
Office of the Commissioners of Patents, with his Petition, on the 26th
December 1857.
I, ALEXANDER CHAPLIN, of Glasgow, in the County of Lanark, North
Britain, Engineer, do hereby declare the nature of the said Invention for
IMPROVEMENTS IN STEAM ENGINES AND IN THE COMBUSTION OF FUEL." to be as
as follows, that is to say:-
This Invention relates more or less to an Invention of "Improvements in
Steam Boilers and in the Combustion of Fuel," for which Mr. Chaplin has
already obtained a grant of British Letters Patent, bearing date on or about
the 10th day of April, 1855. It consists mainly of two general arrangements
of engines respectively fitted for use, as "portable agricultural or roadway
engines," and as" contractors'engines "forgeneral employment on constructive
works. Under both these forms the main details of the engines, boilers, and
furnaces are the same as those already described in the Specification of the
Patent herein-before referred to, but with certain modifications as improve-
ments thereon. The agricultural engine is mounted upon a rectangular
timber frame, the boiler being embraced and supported by brackets from the

page_text: said frame, fitted with shafts for horso traction, with swivelling wheels at the
front, the animal power being principally employed for directing the engine
whilst the ground wheels are geared with the engine's movement to act as
the main drivers. The boiler is upright and tubular, and the engine, single
or double, is attached by brackets to the boiler as a main frame. The furnace
has upon it a short open tube of fire clay, iron, or other material, having an
adjustable top with an outlet for the flow of air up through the bars, so as to
spread within the furnace. The air so supplied becomes highly heated, and
its diffusion consumes or prevents the formation of smoke. The ground
wheels of the engine may either be plain or flanged. In the "contractor's
engine" the same general arrangement is carried out, the engine being
double, and set on a frame ou four ground or rail wheels, the frame carrying
coke and water receptacles if required. The ground or rail wheels are coupled
in the ordinary manner. Both engines can be variously fitted with driving
gear for thrashing, pumping, sawing, hoisting, and other purposes.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Alexander Chaplain in the Great Seal Patent Office on the
25th June 1858.
TO ALL TO WHOM THESE PRESENTS SHALL COME, 1, ALEXANDER
CHAPLIN, of Glasgow, in the County of Lanark, North Britain, Engineer, send
greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Twenty-sixth day of December, in the year of our
Lord One thousand eight hundred and fifty-seven, in the twenty-first year of
Her reign, did, for Herself, Her heirs and successors, give and grant unto me,
the said Alexander Chaplin, Her special license that I, the said Alexander
Chaplain, my executors, administrators, and assigns, or such others as I, the
suid Alexander Chaplin, my executors, administrators, or assigns, should at
ut 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, usc, exercise, and vend, within the United Kingdom of Great Britain
and Ireland, the Chaunel Islands, and Isle of Man, an Invention for "IM-
PROVEMENTS IN STEAM ENGINES AND IN THE COMBUSTION OF FUEL," upon the
condition (amongst others) that I, the said Alexander Chaplin, by an instru
ment in writing under my hand and seal, should particularly describe and
ascertain the nature of the said Invention, aud in what manner the same

page_text: 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 Alexander Chaplin, do hereby declare
the nature of my said Invention, and in what manner the same is to be per-
formed, to be particularly described and ascertained in and by the following
statement, that is to say :-
My said Invention relates more or less to an Invention of "Improvements
in Steam Boilers and in the Combustion of Fuel," for which I have already
obtained a grant of British Letters Patent, bearing date on or about the
Tenth day of April, One thousand eight hundred and fifty-five. It consists
mainly of two general arrangements of engines respectively fitted for use as
"portable agricultural or roadway engines," and as "contractors' engines" for
general employment on constructive works. Under both these forms the
main details of the engines, boilers, and furnaces are the same as those
already described in the Specification of the Patent herein-before referred to,
but with certain modifications as improvements thereon. The agricultural
engine is mounted upon a rectangular timber frame, the boiler being cm-
braced and supported by brackets from the said frame, fitted with shafts for
horse traction, with swivelling wheels at the front, the animal power being
principally employed for directing the engine, whilst the ground wheels are
goared with the engine's movement to act as the main drivers. The boiler is
upright and tubular, and the engine, single or double, is attached by brackets
to the boiler as a main frame. The furnace has upon it a short open tube of
fire clay, iron, or other material, having an adjustable top with an outlet for
the flow of air up through the bars, so as to spread within the furnace. The
air so supplied becomes highly heated, and its diffusion consumes or prevents
the formation of smoke. The ground wheels of the engine may either he
plain or flanged. In the "contractors' engine" the same general arrange-
ment is followed out, the engine being double and set on a frame on four
ground or rail wheels, the frame carrying coke and water receptacles if
required. The ground or rail wheels are coupled in the ordinary manner.
Both engines can be variously fitted with driving gear for thrashing, pumping,
sawing. hoisting, and other purposes.
And in order that my said Invention may be fully understood, I will now
proceed to describe in detail certain modifications under which my improve-
ments may be judiciously carried out in practice.
My present Invention refers more particularly to portable self-propelling
steam engines and to, boilers of the vertical kind. In arranging an engine

page_text: according to one modification, the boiler and engine is surrounded by and
carried upon a rectangular or oblong round-ended framing of iron or of wood
bound with iron, the whole being secured by means of brackets and diagonal
stays. One end of the framing rests upon the axle of the driving road wheels,
and the other end upon the swivel or guiding wheels; the greater portion of
the weight of the engine and boiler is, however, borne by the driving wheels.
The boiler of the engine is vertical, and is fitted internally with a dome or
egg-shaped fire box, which has one or more tubes fitted neross it; these tubes
communicate with the water space at each end, and they are so arranged as
to be higher at one end than the other. This is done in order to cause the
heated water to flow upwards in a current through the tubes. The "tako-
up" or smoke pipe leading from the top of the fire box is in shape somewhat
similar to an inverted cone, that is to say, it is contracted at its lower end in
order that the heat after passing into it may be rapidly diffused owing to the
increased aren of the pipe. This arrangement of the smoke pipe prevents
the injurious action of the heat upon it, whilst scaling is avoided by the
inclination given to its sides; the increase of area likewise prevents the sur-
charging of the steam in the boiler. The entire area of the lower part of the
fire box forms the space for the fire grate. In order to regulate the com-
bustion of the burning fuel, and to consume the smoke arising therefrom, a
current of air slightly above the atmospheric pressure is urged through the
fire grate by means of a fan. A portion of this compressed air is distributed
over the upper surface of the fire; this is effected by means of one or more
pipes or tubular passages placed in a vertical position upon the bars; over tlie
upper orifice of each of these pipes is fixed a slab of fire-brick or a flat plate
of iron in a nearly horizontal position. The compressed air in its passage
through the pipes becomes highly heated, and as it impinges upon the surfaces
of the fire bricks or plates it is distributed on all sides, and thus mingles with
and ignites the combustible gaseous matters. The combustion of the fuel is
in this manner maintained at a regular and uniform rate, and without
dopending upon a free communication with the external atmosphere as in the
ordinary furnace, at the same time the fuel is economised, and an inferior
quality may be used. The engine or engines are attached to the front part
and sides of the vertical boiler, and are carried upon plates, sole plate
brackets, and bolts. The cylinder or cylinders are arranged overhead near to
the steam chest; the pump and valve chest form a self-lubricating guide and
bracket for the piston rod, the crank shaft being fitted below. The details of
the mechanical arrangement for governing or controlling the flow of steam
to the engine consists of a vertical spindle, which is carried in collar bearings

page_text: that are supported by brackets bolted to the surface of the boiler plates. The
vertical spindle is caused to revolve by means of a bevil wheel driven by a
pinion upon the crank shaft. Upon the upper extremity of the vertical
spindle is fixed a socket having jaws upon each side to receive the joints of
the ball levers. Above these joints there is a loose piece which fits easily
into the socket on the vertical spindle; this loose piece has grooves formed in
its periphery which correspond to projections on the inner ends of the short
pieces which are jointed to the ball levers; the loose piece is thus caused to
rise as the balls are depressed and to fall as they are elevated by the variation
of their centrifugal velocity. This variable motion is transmitted to the
throttle valve by means of a light vertical rod fitted to the upper part of the
loose piece, and which opens or closes the valve, and thereby serves to con-
trol and regulate the admission of the steam to the cylinder or cylinders. The
vertical rod swivels in a socket in the upper end of the loose piece; on the
free extremity of the vertical rod in an adjusting screw, jaw, and pin for
connecting it to a lever on the throttle-valve spindle. The power of the
engine is transmitted to the propelling wheels by the following means:---The
crank shaft, which is placed at the lower part of the boiler, and parallel to
the axle of the propelling wheels, has fast to it one or two driving pinions.
These pinions are furnished with clutches or couplings and hand levers, so
that one or both of the propelling wheels may be thrown into or out of gear
as desired, by means of a spur wheel or wheels keyed upon the driving or
road wheels. In this manner the notion of the engine propels the carriage
over the ground according to the ratio of the gearing employed by the
traction of the propelling or road wheels. In arranging and constructing
the road wheels it is preferred to have a portion of the periphery of the
wheels serrated,so that when travelling over soft ground the serrated portion
sinks into and takes hold of the soil, thereby assisting the locomotion of the
engine over the ground. The serrated portion of the periphery does not
project beyond the plaiu part of the circumference, in order that when the
engine is progressing over firm ground the superincumbent weight is borne
upon the plain surface of the wheels, and the machine moves smoothly and
steadily onwards. The projecting teeth or serrations may be of various
dimensions. It is preferred to make them of a simple V shape, and not
placed close together, but, at regular intervals apart around the periphery of
the wheel. When the engine is in motion and travelling over the ground, it
is guided in its course by the driver or engineer, who by turning a hand wheel
actuates a screw worm wheel and lever, which causes the leading road wheel
or wheels to turn in the required direction. One or two leading road wheels

page_text: may be employed at one end of the carriage,.ench wheel being made to swivel
upon its own axis, so as to cause the engine to deviate to the right or left, as
required. These engines are also fitted with an arrangement by which a
horse or other animal may at any time be yoked between trams to guide the
course of the engine, the propelling power being derived from the action of
the steam engine, whether the guiding of the carriage is effected by manual
or horse power. An engine of this kind may be used upon a road, a railway,
or a tramway; in the two latter cases the wheels are keyed upon rotatory
axles, and the guiding apparatus is dispensed with. In all cases, however,
the ratio of the gearing to the driving wheels may be changed from time to
time in order to obtain the proper working velocity of the piston, and vary
the speed of the carriage according to the load imposed upon the engine.
The coal boxes and tank for holding the feed water are arranged beneath the
main framing of the carriage in the space usually left for the swivelling of
the front pair of road wheels of an ordinary carriage or in a portable engine
of the ordinary horizontal construction. The carriage frame and wheels of
this machine being removed, the boiler and engine may be used for stationary
purposes. The boiler of these improved engines may be fired either from
a platform placed between the sides of the framing or from the ground.
With these several improvements locomotive and portable steam engines are
thereby rendered more extensively available and economical i use than
has hitherto been the case. These engines are more capable of going over
marshy, boggy, or sandy land with ease and celerity, so as to render them
highly useful adjuncts in situations where engines of the ordinary kind
would be useless.
Having now described and particularly ascertained the nature of my said
Invention, and the manner in which the same is or may be used or carried
into effect, I may observe in conclusion, that I do not confine or restrict
myself to the precise details or arrangements which I have had occasion
to describe or refer to, as many variations may be made therefrom without
deviating from the principles or main features of my Invention; but what
I consider to be novel and original, and therefore claim as the Invention
secured to me by the herein-before in part recited Letters Patent is,-
First, the general arrangement and construction of locomotive and
portable steam engines, as herein-before described.
up
Second, the system or mode of arranging and constructing the "take-
"or smoke-pipe in locomotive or portable engine boilers of the vertical
kind for the purpose of preventing the injurious action of heat thereon, as
herein-before described.

page_text: 'Third, the system or mode of regulating or forcing the combustion of the
fuel by means of compressed air applied beneath the fire-grate, and flowing
through a vertical pipe or pipes, and diffused in the furnace by a deflecting
plate or plates, as herein-before described.
Fourth, the system or mode of controlling or governing the admission of
the steam to the steam cylinder or cylinders by means of a self-acting
mechanical arrangement, as herein-before described.
Fifth, the system or mode of arranging and constructing the road wheels
of engines in which the peripheries of the wheels are partly serrated and
partly plain, as herein-before described.
Sixth, the system or mode of guiding or directing the course of locomotive
engines upon common roads, as herein-before described.
Seventh, the system or mode of imparting motion to the driving wheels
of locomotive engines by means of the mechanical arrangement herein-
before described, or any mere equivalent therefor.
In witness whereof, I, the said Alexander Chaplin, have hereunto set
my hand and seal, this Twenty-fourth day of June, One thousand
eight hundred and fifty-eight.
ALEX CHAPLIN. (L.8.)