IMPROVEMENTS IN PORTABLE STEAM FIRE ENGINES
Year: 1880

page_text: LETTERS PATENT to Henry Merryweather, of the Firm of Merryweather and
Sons, Engineers and Fire Engine Makers, of Greenwich, in the County of
Kent, and Francis Michael Cotton, of the Firm of Field, Field, and Cotton,
Consulting Engineers, of Chandos Chambers, Adelphi, in the County of
Middlesex, for an Invention of "IMPROVEMENTS IN PORTABLE STEAM FIRE
ENGINES"
PROVISIONAL SPECIFICATION left by the said Henry Merryweather and
Francis Michael Cotton at the Office of the Commissioners of Patents on
the 25th August 1880.
HENRY MERRYWEATHER, of the Firm of Merryweather and Sons, Engineers and
Fire Engine Makers, of Greenwich, in the County of Kent, and FRANCIS MICHAEL
COTTON, of the Firm of Field, Field, and Cotton, Consulting Engineers, of Chandos
Chambers, Adelphi, in the County of Middlesex. "IMPROVEMENTS IN PORTABLE
STEAM FIRE ENGINES."
In portable steam fire engines as hitherto usually constructed it has been found
difficult to draw water from a greater depth than from 10 to 18 feet, and in those
engines which have been able to draw from a greater depth it has been found
necessary, in order to get rid of air in the valve chambers and passages, to contract
them to such an extent as to seriously interfere with the free flow of the water.
According to our Invention we obviate this difficulty in the following manner :-
Making the pump valve chambers and passages of forms and proportions best
suited for free flow of the water, we apply at the highest part of the supply
passages above the suction valves a steam ejector, by which we extract the air and
draw up water so as completely to fill the pump, pipes, passages, and valve chambers
with water, whereupon the engine can be started without danger to the working
parts and continue drawing from a considerable depth without difficulty.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said Henry Merryweather and Francis Michael Cotton in the Great
Seal Patent Office on the 25th February 1881.
HENRY MERRYWEATHER, of the Firm of Merryweather and Sons, Engineers and
Fire Engine Makers, of Greenwich, in the County of Kent, and FRANCIS MICHAEL
COTTON, of the Firm of Field, Field, and Cotton, Consulting Engineers, of Chandos
Chambers, Adelphi, in the County of Middlesex. "IMPROVEMENTS IN PORTABLE
STEAM FIRE ENGINES."
In portable steain fire engines as hitherto usually constructed it has been found
difficult to draw water from a greater depth than from 16 to 18 feet, and in those
engines which have been able to draw from a greater depth it has been found
necessary, in order to get rid of air in the valve chambers and passages, to contract
them to such an extent as to seriously interfere with the free flow of the water.
According to our Invention we obviate this difficulty in the following manner :-
Making the pump valve chambers and passages of forms and proportions best
suited for free flow of the water, we apply at the highest parts of the supply
passages above the suction valves a steam ejector, by which we extract the air and
draw up water, so as completely to fill the pump pipes, passages, and valve
chambers with water, whereupon the engine can be started without danger to the
working parts and continue drawing from a considerable depth without difficulty.
Referring to the Drawings, Fig. 1 is a side elevation, and Fig. 2 an end elevation
of so much of a portable double-acting steam fire-engine as is needful to illustrate
the application of our Invention. The pump valve chambers a, a, and water ways
b, b', are made large, so as to allow free flow of water, instead of being of small
capacity as compared with the barrel, as is usual in ordinary portable steam fire-
engines designed to draw from a considerable depth. To each pump valve chamber
a, a', is connected by pipe can ejector à of any suitable construction, preferring
the kind known as Körting's, and which is by pipe e connected to the boiler of the
steam fire-engine, a valve cock being interposed. Communication between the
valve chambers and ejector is governed by a three-way cock f. By this arrange-
ment when the three-way cock is open the ejector is in communication through
the pump valve chambers with the highest parts of the supply passages above the
suction valves, and if steam be now turned on to the ejector air will by its action
be exhausted and water drawn up so as to completely fill the pump, pipes, passages,
and valve chambers.
As is evident the forms of the pump valve chambers and passages may be
modified without departure from the peculiar characteristic of our Invention, so
long as they be made of such capacity relative to that of the pump barrel as to
allow of free flow of the water. Also it will be evident our Invention is equally
applicable to single acting portable steam fire engines and to such as have more than
one pump barrel. It is to be noted that we do not make any separate claim to
novelty in respect of making the pump valve chambers and passages of forms and
proportions best suited for the free flow of water; but what we do claim in portable
stear fire engines is the application and use in conjunction with pump valve
chambers and passages, constructed to allow free flow of water, of an ejector in
connection with the supply passage or passages above the suction valve or valves,
substantially as and for the purpose hereinabove set forth.
In witness whereof, I, the said Francis Michael Cotton, have hereunto set
my hand and seal, this Twenty fifth day of February, in the year of our
Lord One thousand eight hundred and eighty one.