Improvements in Steam and Vapour Engines.
Year: 1896

page_text: Date of Application, 2nd June, 1896
Complete Specification Left, 27th Feb., 1897-Accepted, Sth May, 1897
PROVISIONAL SP
ION.
Improvements in Steam and Vapour Engines.
I EDWARD JAMES DUFF, Engineer, Glengarriff, Cressington Park, near
Liverpool County Lancaster do hereby declare the nature of this invention to be
as follows:-
My said invention consists of an improvement in steam and vapour engines
whereby I attain compound action of the stearn in one double acting steam cylinder,
and by one steam distributing valve.
I construct the steam or vapour cylinder with one half of its length of smaller
diameter than the other half. In the part of the cylinder of smaller diameter a
high pressure piston works, and in the part of the cylinder of larger diameter a
low pressure piston works, both pistons are mounted on the same piston rod. The
movement of the pistons is made in one direction by the pressure of the steam
admitted to the outer side of the high pressure- or small-piston, and the movement
of the pistons in the opposite direction is made by the second action of the same
steam admitted to the outer side of the larger piston. The steam distributing
valve works in connection with three steam ports-one steam port being in
communication with the outer end of the small piston, a second steam port in
connection with the outer end of the large piston, and a third steam port
in connection with the exhaust port of the engine. The steam is first admitted to
the outer end of the small piston from which-on the return stroke-it passes
through a port in the valve to the outer end of the large cylinder; on the return
stroke of the large piston the steam passes to the exhaust port of the engine.
The steam controlling valve for this purpose being preferably a slide valve
admitting steam to the high pressure cylinder in the usual way, but constructed
with a communicating passage-or port-through the interior of the valve to
conduct the steam issuing from the high pressure end of the cylinder to the port
leading to the low pressure end of the cylinder, where the steam having acted on
the low pressure piston is allowed to escape under the slide valve to the exhaust
port of the engine in the usual way. The slide valve is preferably moved by an
eccentric in the way common to most steam valves.
By the improved arrangement of cylinder, pistons, & valve described herein
I am enabled to secure high economies in the use of steam, in a simple &
comparatively inexpensive manner, as I secure compound action of the steam in
one cylinder, and by the action of one valve and one valve motion gear. These
advantages make it practicable to convert many existing engines into more
economical steam users, at a small cost.
Dated this Thirtieth day of May 1896.
EDWARD JAMES DUFF.

page_text: Improvements in Steam and Vapour Engines.
I, EDWARD JAMES DUFF, Engineer, Glengarriff, Cressington Park, Liverpool,
County Lancaster, do hereby declare the nature of this invention and in what
imanner the same is to be performed, to be particularly described and ascertained
in and by the following statement, that is to say:-
My said invention has for its object to obtain increased efficiency in steam and
vapour engines at comparatively little cost; and to this end I construct the steam
or vapour cylinder with one half of its length of smaller diameter than the other
half, pistons, joined by a rod, being fitted to work in each half. One steam
distribution valve, specially constructed and driven by ordinary gear is provided.
And in order that my said invention and the manner of performing the same
may be properly understood I hereunto append a sheet of explanatory drawings to
be hereinafter referred to, and showing as much of my improved engine as is
sufficient to explain it.
Figure, 1, of the drawings is a vertical section of the cylinder of my improved
engine.
Figure, 2, is an elevation of the steam distribution valve of my improved
engine, as viewed from the inner side.
In these drawings the same reference letters are used to mark the same or like
parts wherever they are repeated.
In carrying out my invention I construct the steam or vapour cylinder, A, with
one half of its length of smaller diameter than the other half and I fit a piston
to work in each half, both pistons, B, and C, being mounted on the same piston
rod, D. The movement of the pistons, B, and C, in one direction is effected by
the introduction to the smaller half of the cylinder, A, above the upper and outer
side of its piston, B, of steam of a pressure similar to the initial steam pressure
obtaining in well-designed compound engines; and the movement of the pistons, B,
and C, in the other direction is effected by the expansive action of the steam, first
dealt with, which at the proper time is exhausted from the smaller half of the
cylinder to the larger half of the cylinder below the lower and outer side of its
piston, C. The steam distribution valve, E, works in connection with three steam
ports, G, H, and J, formed in the cylinder. The steam port, G, communicates
with the space in the cylinder above the upper and outer side of the smaller
piston, B; the steam port, H, communicates with the space in the cylinder below
the lower and outer side of the larger piston, C; and the port, J, communicates
with the exhaust pipe, K, of the engine. Steam admitted into the cylinder to act
on the small piston, B, escapes at the proper time, by the movement of the valve, F,
through the port, G, a passage, L, in the valve, and the port, H, to act on the
large piston, C, and having acted thereon, escapes at the proper time to the exhaust
pipe, K, by the port, HI, and the exhaust cavity, M, in the valve. The distribution
valve, E, is worked by an eccentric or equivalent in an well known way. An
opening N, communicating with the exhaust pipe, K, and the space between the
pistons, B, and C, is formed in the cylinder for the purpose of relieving back
pressure. The distribution valve, E, is shown as a slide valve, but may be arranged
as a piston valve in an equivalent manner.
By the improved construction and arrangement of parts herein before described
great economy of steam is effected in a simple and inexpensive manner, the steam
being expansively employed in a manner somewhat similar to that in two-stage
compound engines while oue steam distribution valve and valve gear only are
employed. The simplicity of the invention renders it easily adaptable to many
existing engines with advantageous results.

page_text: Having now particularly described and ascertained the nature of my said inven
tion and in what manner the same is to be performed, I declare that what I
claim is :-
The construction, arrangement, and combination of parts constituting the
improved steam or vapour engine substantially as hereinbefore described and as
shown in the accompanying drawings.
Dated this Twenty-sixth day of February 1897.
EDMUND HUNT,
Applicant's Agent.