IMPROVEMENTS IN STEAM ENGINES
Year: 1874

page_text: PROVISIONAL SPECIFICATION left by William Robert Lake at the
Office of the Commissioners of Patents, with his Petition, on the
6th April 1874.-A communication from abroad by the Reverend
John Chatfield Nobles, of Elmira, New York, United States of
America.
I, WILLIAM ROBERT LAKE, of the Firm of Haseltine, Lake, & Co.,..
Patent Agents, Southampton Buildings, London, do hereby declare the
nature of the said Invention for "IMPROVEMENTS IN STEAM ENGINES," a
communication, to be as follows:-
The first part of my said Invention relates to a double cylinder engine
and consists in the peculiar construction and arrangement of the parts of
the engine as herein set forth. The two cylinders of the said engine are
placed opposite or in a line with each other, and on opposite sides of the:
crank shaft, and their front or adjacent ends are connected with a central
chamber in which the cranks are placed, and which is just large enough
to allow the cranks to turn therein. The said cranks are not placed
exactly at right angles to each other or 90 degrees apart, as in ordinary
double cylinder engines, and therefore neither crank will be on its dead.
centre when the piston connected with the other crank is at half stroke.

page_text: "
The pistons of the said cylinders are provided with “trunks" which are
not made cylindrical as in ordinary trunk engines, but have an oblong
transverse section, the longest diameter of which is sufficient to permit
the angular motion of the piston rods, while its width is just large
enough to permit the said rods to work freely therein. These "trunks
are fitted to work through stuffing boxes in the cylinder ends. And it
is obvious that their cross sectional area will be much less than that of
ordinary cylindrical trunks, and that they will but very slightly diminish
the effective area of the pistons.
This improved engine may be provided with an ordinary slide valve or
with the rotating valve and reversing apparatus herein-after described.
The said Invention relates, secondly, to a peculiar distributing and
reversing valve for compound engines, and chiefly applicable to those
engines which have three cylinders, whose pistons are connected to a
common crank arranged centrally between the said cylinders. In these
engines the cylinders are arranged in connection with a central chamber,
and open into the same, and the crank shaft passes through the said
chamber which is provided at its ends with covers fitted with stuffing
boxes for the said crank shaft to work in. One of these covers is made
to form the valve seating. For this purpose it is recessed on its inner
side to receive the valve which is a disc or circular plate, and is fitted to
turn. freely upon a sleeve or boss projecting from the centre of the said
recess, one of its faces fitting and covering the flat surface of the same.
The said recess has three ports or openings from each of which a pipe or
passage extends to the outer end of one of the cylinders. A small
circular groove or channel is formed in the said recess immediately sur-
rounding the aforesaid sleeve, and into which the steam supply pipe or
passage opens. The valve has a cavity on its inner side which is always
open to the said channel, and which is also large enough to cover two
of the aforesaid steam ports, therefore as the said valve rotates its covers-
and uncovers all of the said ports successively. The said valve also has
an aperture through it which forms a passage for the exhaust steam
escaping from the aforesaid ports to pass therefrom to the aforesaid
central or crank chamber, which is open to the exhaust pipe or passage.
This part of my Invention consists in a peculiar contrivance whereby
the said valve is adjusted to reverse the engine when the same is running-
in either direction, for this purpose I attach to the outer end of the
aforesaid sleeve or tube through which the shaft passes a flange wherein

page_text: I form two holes or notches diametrically opposite each other. And on
the shaft I fit a ring or collar which has a flange provided with two pins
or studs occupying positions corresponding with those of the aforesaid
holes or notches. This ring or collar is secured on the shaft by means of
a feather or stud on the latter, which projects into a longitudinal groove
or slot in the said ring, so that the same.can slide endwise upon the said
shaft but cannot turn independently of the same. Now it is obvious
that as the said ring turns with the shaft the pins or studs thereof
occupy a fixed or unalterable position with regard to the crank and
pistons, and that if the aforesaid valve were attached unadjustably to this
ring or collar, the valve would also be unchangeable with regard to the
crank, and the engine could not be reversed. But by drawing the said
ring back on the shaft to release the said pins from the holes or notches,
and allowing the shaft to make one half revolution, or turning the ring
half way round upon the said slot and then restoring the connection of
the said pins and holes the position of the valve with regard to the
cranks will be changed, and the direction of the engine's motion
reversed. I prefer to have a spring placed at the back of the said ring
to keep it up to the flange of the sleeve. And a lever is provided for
effecting the adjustment of the said ring upon the shaft.