IMPROVEMENTS IN THE CONSTRUCTION AND ARRANGEMENT OF THE BOILERS AND WORKING PARTS OF STEAM FIRE ENGINES, PART OF WHICH IS APPLICABLE TO ENGINES FOR OTHER PURPOSES
Year: 1858

page_text: .
PROVISIONAL SPECIFICATION left by Joseph G. E. Larned at the
Office of the Commissioners of Patents, with his Petition, on the
7th December 1858.
I, JOSEPH G. E. LARNED, of the City of Brooklyn, in the State of New
York, United States of America, do hereby declare the nature of the said
Invention for "IMPROVEMENTS IN THE CONSTRUCTION AND ARRANGEMENT OF THE
BOILERS AND WORKING PARTS OF STEAM FIRE ENGINES, PART OF WHICH IS
APPLICABLE TO ENGINES FOR OTHER PURPOSES," to be as follows:-
The construction of the boiler is such as to secure a large extent of fire and
water surface within a small area, and also obtain a great degree of strength
with lightness of material or structure. For this end the boiler and furnace
are constructed of tubes, such form giving the greatest degree of strength with
a given quantity or weight of metal. The boiler consists of sets or pairs of
vertical tubes, arranged annularly or one within the other, the outer tube
being in size, in respect to the inner tube, about as two and a half inches to
one and a half, and the annular space between such tubes being occupied by
water. The inner tube is an air tube, and through it the heat passes, and also
round about the outer tubes, the fire or heat is thus brought in contact with
both sides or surfaces of the water. The furnace is also composed of tubes
set close together and opening at the bottom into a ring-shaped water bottom,
and into the steam drum above. This construction and arrangement of boiler
secures and unites great compactness and lightness of structure with great

page_text: strength and power, and renders it possible to generate in a very few minutes
steam sufficient for active constant use. The weight of the boiler need not
exceed seven pounds to the square foot of fire surface, and its fire surface is
also much more effectual than in any ordinarily constructed boiler. A boiler
of this construction four feet in diameter by six and a half feet high will give
as much as four hundred and seventy-five square feet of fire surface, and a
boiler of such dimensions actually constructed bas been worked to over one
hundred and twenty horse power, and with perfect safety, and without reaching
the limits of its power. The general arrangement of the machinery is that of
a locomotive with outside connections, and the valves are worked by link
motion, so that steam can be cut off at any point of the stroke, giving the
benefit of expansion in any desired degree, or may be instantaneously reversed.
The connecting rods from the engines act upon cranks, which, however, are not
placed as in locomotives ordinarily upon the shaft of the driving wheels, but
upon an intermediate shaft revolving in fixed bearings upon the frame, &
operating the force pumps. From such intermediate shaft power is trans-
mitted to the driving wheels by a parallel rod, the axis of the driving wheels
being kept at an uniform distance from the intermediate shaft by two strong
arms or rods, which take hold by means of suitable boxes of each end of the
intermediate shaft near its bearings, and of the axle of the driving wheels near
their hubs. The moving parts of the engine are thus kept undisturbed by the
motion of the wheels, however rough the road may be, the power being
accurately transmitted to the wheels, whatever position they may have above
or below the center line of the cylinder. Ball and socket joints at the ends of
the parallel rods, and the arms between the intermediate shaft and the axis of
the driving wheels, protect against any side movement or twist.
As soon as
the engine reaches a fire the parallel rods are disconnected, which is the work
of but an instant, and the power then acts upon the pumps alone.
When constructed as above described, the machine is self-propelling, and
supplies its own power to move itself from place to place. If for any reason
it is desired not to have this self-propelling feature or arrangement connected,
the parallel rods, and those which keep the axle of the driving wheels at an
uniform distance from the intermediate shaft, will be dispensed with, and any
form of engines, as oscillating, &c., may be used to work the intermediate
shaft and pumps. The fore axle is connected to the machine by means of two
springs, one above the other, in the line of the centre of the carriage, which
take hold of a vertical spindle connected with the fore axle, and having at the
top a horizontal crank, operated by a screw, sleeve, and winch, by which the
direction of the axle is controlled, and the carriage steered.

page_text: The Invention consists generally in the construction of a boiler upon the
plan or principle described, such boiler can be also applied to engines of other
kinds, and in the combination and arrangement of the working parts of the
machinery for transmitting power from the cylinders through an intermediate
shaft to the driving wheels, and the combination of such intermediate shaft
with any suitable hydraulic apparatus, whether a rotary pump centered on such
shaft, or a reciprocating pump operated by cranks on such shaft, which in
such case becomes a crank shaft or axle and for steering the carriage.