AN IMPROVED FEED-WATER APPARATUS CHIEFLY DESIGNED FOR SUPPLYING AND MAINTAINING A PROPER WATER LEVEL IN STEAM BOILERS
Year: 1869

page_text: PROVISIONAL SPECIFICATION left by Sumner Shaw at the Office of
the Commissioners of Patents, with his Petition, on the 19th April
1869.-A. communication from abroad by Philander Shaw, of
Boston, Massachusetts, United States of America.
I, SUMNER SHAW, of Boston, Massachusetts, United States of
America, now of No. 8, Southampton Buildings, Chancery Lane, in the
County of Middlesex, do hereby declare the nature of the said In-
vention for "AN IMPROVED FEED-WATER APPARATUS CHIEFLY DESIGNED FOR
SUPPLYING AND MAINTAINING A PROPER WATER LEVEL IN STEAM BOILERS," a
communication, to be as follows:-
My said Invention relates to an apparatus which constantly delivers
to the boiler & quantity of water exactly equivalent to the quantity
evaporated or otherwise withdrawn from the same.
I obtain this result by means of the following apparatus:-In a piston
which is fitted to work in a pump, barrel, or cylinder I form a chamber
which as the piston moves to and fro in the cylinder is alternately
brought opposite to each one of two apertures, one of which com-
municates with the source of supply and the other with the boiler.
The centre of the said chamber coincides with the desired water level

page_text: in the boiler. The chamber is filled with water through the supply
aperture and carries the same to the outlet aperture, through which
if the water in the boiler has fallen below the proper level this water
or a portion of it will flow, but if the water in the boiler has not sunk
below its proper level no water will flow from the chamber, which will
simply work to and fro, presenting its contents to the delivery aperture
at every stroke, so that so long as the tank is kept properly filled
the boiler can never be short of water, while on the other hand if the
apparatus is properly constructed it can never be too full, as there must
be some difference between the water level of the chamber and that
of the boiler to cause the water to flow into the latter.
In connection with the delivering chamber and to prevent the heating
of the same by the entrance of steam therein I use an air pump which
at each stroke supplies to the chamber a sufficient quantity of air
to fill the chamber as the water leaves it.
The cylinder or barrel is constructed of cast iron or other suitable
metal, and the piston or plunger is properly fitted therein and kept
tight at the ends by stuffing boxes. The said plunger is provided with
a rod through which it is operated from any convenient working part
of the engine. At or near the middle of the plunger is formed the
conveying chamber whose capacity must be adapted to that of the
boiler. One end of the cylinder forms the air pump and is provided
with a suitable arrangement of valves for forcing air into a receiver
herein-after described. The supply and delivery apertures are formed
at a convenient distance apart, and the travel of the plunger must be
regulated to carry the chamber from one to the other of these apertures.
The supply aperture is connected by a pipe with a tank or cistern,
whose contents may be heated by passing the exhaust steam through
a coiled pipe placed therein. I also provide the cylinder with a relief
aperture for the escape of the air, which aperture is formed opposite
to the supply aperture, a pipe leading therefrom to the tank. The
delivery aperture communicates with the boiler through a tube, and
opposite to the said aperture is another, which also communicates with
the boiler through an air receiver which is supplied with air by the
pump. The said air receiver is of a spherical or other suitable form
and is divided internally by a diaphragm provided with a valve which
permits the escape of the air when the pump forces into the receiver
more than is required. Through the said valve is a small perforation

page_text: which remains always open so that the pressure of steam and that
of the air upon the diaphragm may be equalized. The relief pipe may
be provided at its upper end with a whistle which will give timely
notice if the water in the tank should get low.
In applying my apparatus to boilers which work with the steam
at a very high pressure the pump may be cooled by passing around it
the cold water with which the tank is supplied.