IMPROVEMENTS IN AND CONNECTED WITH THE PISTONS OF AIR AND GAS ENGINES
Year: 1876

page_text: LETTERS PATENT to William Robert Lake, of the Firm of Haseltine, Lake,
& Co., Patent Agents, Southampton Buildings, London, for the Invention of
"IMPROVEMENTS IN AND CONNECTED WITH THE PISTONS OF AIR AND GAS
ENGINES." A communication from abroad by George Bailey Brayton, of
Exeter New Hampshire. United States of America.
led the 12th January 1877, and dated the 15th November 1876.
COMPLETE SPECIFICATION filed by the said William Robert Lake at the
Office of the Commissioners of Patents on the 15th November 1876.
WILLIAM ROBERT LAKE, of the Firm of Haseltine, Lake, & Co., Patent Agents,
Southampton Buildings, London. "IMPROVEMENTS IN AND CONNECTED WITH THE
PISTONS OF AIR AND GAS ENGINES." A communication from abroad by George
Bailey Brayton, of Exeter, New Hampshire, United States of America.
It has been necessary heretofore to construct on the single acting principle
engines which are designed to employ as a motive power heated air or mixtures
expanded by ignition of atmospheric air and carburetted hydrogen, or mixtures of
air and light vapors of hydrocarbons, for the reason that the pistons of such engines
become very highly heated. This Invention is intended to provide a method of
construction whereby the pistons of such engines can be kept entirely cool, and
machines of this class may be made double acting.
According to the said Invention I construct the piston with a hollow chamber in
combination with a hollow double piston rod to provide means for the continuous
circulation of a stream of cold water through the piston and its rods.
The said Invention is illustrated in the accompanying Drawing, partly in
perspective and partly in vertical section.
A represents the cylinder and B the piston of an engine. The necessary valves
and passages for admitting the motive agent to act against one side of the piston
and afterwards against the other for driving the piston to and fro within the
cylinder are omitted for the reason that such adjuncts of a complete machine
constitute no part of the present Invention and are not necessary for an under-
standing of the same. It is to be understood however that the said engine has
suitable valve mechanism for enabling the motive fluid to be properly introduced
into the cylinder alternately upon opposite sides of the piston, that it has suitable

page_text: exhaust passages, and that its piston rod is connected with a crank shaft or other
means for converting a reciprocating into a rotary motion.
The interior of the piston is formed into a chamber, as seen at a.
The piston
rods are two in number B1, B2, each of which has its axis hollow and communicates
with the piston chamber a. In this instance they are separate and each has its
appropriate stuffing box b, b', in the upper cylinder head, but in place of these a
double piston rod may be used consisting of two tubes, one within the other, and
arranged so that there shall be an annular space between the exterior surface of the
inner tube and the interior surface of the outer one. Or I may employ a single
hollow piston rod with its interior divided into two passages by a partition through
the central axis. Or there may be a solid piston rod and two passages formed by
separate tubes communicating with the chamber or hollow space in the piston,
which will perform the same office as means for enabling water to be circulated
through the piston as the hollow piston rods above described perform.
Each hollow piston rod has attached to it a flexible tube C, C¹. The tube C
representing the one through which the supply of cold water is introduced should
be connected at its other end with some suitable source of water supply so that a
constant stream of cold water can flow under pressure through the piston rod B¹
into the chamber a of the piston, and be discharged by passing upward through the
piston rod B, and thence be conducted through the flexible tube C¹ to the point
where it is to be discharged or utilized for any purpose.
The source of water supply may be a tank or cistern, so elevated above the
cylinder as to exert a pressure due to its gravity; or water may be injected by a
force pump; or its supply may be obtained from a street main.
By this construction the pistons of the said engines can be kept so cool that it
will be practicable to furnish the cylinder with heads at both ends and apply the
agent of force alternately upon each side of the piston without injury from over
heating either to the piston or to the interior surface of the cylinder.
And in case a motive power derived in part from the lighter products of petroleum
oils should be employed it will be found that the heat is insufficient to decompose
the constituents of the oil and leave a deposit upon the surface of the cylinder, but
on the contrary the surface of the cylinder and the sides of the piston remain clean
and bright.
While it will be found generally very convenient to make use of flexible tubes in
combination with the hollow piston rods and a piston as described it is quite
apparent that metallic pipes may be substituted for such tubes and the piston rods
be connected therewith by causing the latter to slide within the bore of such pipes,
the joints being made tight by suitable packing.
Having thus fully described the said Invention as communicated to me by my
foreign correspondent, and the manner of performing the same, I wish it understood
that I claim,-
First. The improvement in pistons for gas and hot-air engines which consist in
constructing the piston with an interior chamber connected with double hollow
piston rods or equivalent tubes for enabling a continuous supply of water to
be circulated through the piston for the purpose of cooling the same, as above
specified.
Second. The combination of a hollow piston with a suitable source of water
supply whereby the piston is kept cool by a continuous water circulation through
the same, as above specified.
In witness whereof, I, the said William Robert Lake, have hereunto set my
hand and seal, this Fifteenth day of November, in the year of our Lord
One thousand eight hundred and seventy-six,