IMPROVEMENTS IN MOTIVE-POWER ENGINES ACTUATED BY STEAM OR OTHER VAPOUR
Year: 1868

page_text: PROVISIONAL SPECIFICATION left by Frederick William Gerhard at
the Office of the Commissioners of Patents, with his Petition, on
the 5th May 1868.
I, FREDERICK WILLIAM GERHARD, of Wolverhampton, in the County
of Stafford, Chemist, do hereby declare the nature of the said Invention
for "IMPROVEMENTS IN MOTIVE-POWER ENGINES ACTUATED BY STEAM OR OTHER
VAPOUR," to be as follows:-
My Invention consists of the improvements herein-after described in
motive-power engines actuated by steam or other vapour, by which
improvements great economy is effected in consequence of the utilization.
of the waste heat of the waste steam or other vapour.
I will describe my Invention with reference to a steam engine. To
the end of the waste or eduction pipe of the cylinder of the engine I
connect a second pipe of about the same diameter as the said eduction
pipe, which said second pipe conducts the waste steam to a second or
waste steam cylinder, by preference somewhat larger than the cylinder
of the steam engine. I do not however limit myself to the size of the
said waste steam cylinder. To the end of the waste steam cylinder,
opposite to that at which the steam is introduced, I connect another

page_text: smaller pipe communicating with a boiler of the same or nearly the
same size as the boiler by which the steam was originally generated.
The necessary quantity of water is placed in the second boiler and the
waste steam introduced heats the said water and produces from it steam
of sufficient pressure to work an engine of or nearly of the same size as
that from which the waste steam was obtained.
If a third engine be required, a similar arrangement can be adopted
with respect to the waste steam of the second engine, and so on.
The waste steam is ultimately utilized in the following manner :-If
no second engine be required the waste steam cylinder is arranged
in the manner already described, and by its use a perfect vacuum is
produced on the exhaust side of the piston of the engine. The pipe
from the waste steam cylinder conveys the steam to a tank or reservoir
containing feed water, the temperature of which will be raised by the
said waste steam to the boiling point. Should the waste steam cylinder
be applied to a locomotive engine to produce a vacuum, the pipe at
the opposite end to the locomotive cylinder must be made to pass into
the chimney as at present. If the steam should be required of greater
elasticity than the atmospheric pressure the pipe connected with the
waste steam cylinder must be connected with a second boiler or vessel
of the necessary dimensions, and the steam when brought to the
required pressure conveyed again into the boiler where it was generated.
This arrangement is admirably adapted for rotary engines.
If two or more boilers are required to be heated the waste steam
cylinder may be so arranged that a flue from the furnace which heats
the boiler can be made to enclose or partly to surround them, and to
terminate in the chimney again at a proper height above the fire-grate.
Instead of the waste steam cylinder, a coil of piping may be substituted
of convenient dimensions to produce a vacuum and to convey the waste
steam or other elastic fluids into boilers and tanks, as already described.