Improvements in Steam Engines.
Year: 1889

page_text: Date of Application, 7th Dec., 1889
Complete Specification Left, 8th Sept., 1890-Accepted, 8th Nov., 1890
Improvements in Steam Engines.
We, WILLIAM HENRY ALLEN, RICHARD WRIGHT, and RICHARD WILLIAM ALLEN,
Engineers, of York Street Works, Lambeth, in the County of Surrey, do hereby
declare the nature of this invention to be as follows:-
Our invention relates to steam engines in which steam at a sufficiently high pressure
is admitted to a cylinder, after actuating the piston in which it passes to a larger
cylinder in which it continues to do useful work during its expansion, and in some
cases is subsequently passed to one or more still larger cylinders. It is applicable
more especially to that form of such compound triple or quadruple engines in which
double acting cylinders are arranged side by side, the pistons operating by connecting
rods directly upon cranks arranged opposite to each other or at other angles upon
the shaft.
In such engines as ordinarily heretofore made, the steam is first admitted into a
steam chest where it is distributed by means of an ordinary slide valve to the smallest
or high pressure cylinder where after having usually been expanded to some extent it
passes back through the exhaust port to the slide valve and through it to an external
eduction pipe to the steam chest of the larger or low pressure cylinder into which it
is admitted by another slide valve, and after having completed its expansion passes
away through the exhaust pipe. In such method of arrangement the steam both at
its higher pressure and after expansion passes through the same valve, a considerable
loss resulting from the reduction in heat of the high pressure steam, and from the
external eduction pipe, whilst the ports or passages are necessarily of considerable
length and size, and it is impossible to obtain high efficiency both on this account
and on account of the condensation arising from the causes mentioned.
Our invention has for its objects improved methods of constructing and arranging
such engines so that the objections described are overcome, and they are very efficient,
simple, compact, and durable.
We admit the steam to the smaller or high pressure cylinder through a valve which
is not used as an exhaust valve also, but simply as an admission and cut off valve
working close to the ports at the ends of the cylinder, the valve being preferably
cylindrical and of sufficient diameter and length at each end of the valve spindle, and
working in a corresponding cylindrical chamber parallel with the bore of the cylinder
and as close to it as possible, so that the ports may be as short as possible.
The steam is admitted between these two cylindrical valves, which are actuated by
an excentric arranged in the ordinary way so as to open the ports alternately at or
somewhat before the beginning of each stroke of the piston, and to cut off the steam
at any determined point of the stroke.
As the exhaust steam does not pass through these valves the initial heat of the
steam is maintained.
The steam is exhausted from the cylinder through two separate ports preferably
opposite to the admission ports, these exhaust ports being carried in the usual way to
near the centre of the cylinder where they enter a chamber in which works a
cylindrical valve between the smaller high pressure cylinder just described and the
adjoining larger low pressure cylinder. This cylindrical valve serves both as the
eduction valve of the small cylinder, and the admission or distributing valve of
the larger cylinder the ports of which are made as short as possible and pass direct
from the cylindrical valve chamber to the ends of the cylinder.
The cylindrical valve is made hollow, suitable ports being made through its sides
which serve as eduction ports from the small cylinder and others which serve as

page_text: admission ports to the large cylinder, and being arranged so as to open and close
the several openings or ports at the right times.
The passages from the central valve open into a valve chamber communicating with
the ports to the larger cylinder and the chamber may serve as a receiver between
the two cylinders and is preferably steam jacketted.
For engines having their cranks at opposite angles the receiver may if desired be
entirely dispensed with, the central valve acting as an inlet and outlet valve direct,
without a receiver.
The cylindrical valve described is provided with a valve spindle actuated by a
separate excentric in the usual way.
In large engines constructed according to our invention, we prefer to use two
separate cylindrical valves between the two cylinders instead of a single one
only as just described. In such case we make two separate cylindrical chambers
side by side each containing a cylindrical valve, one serving as an exhaust valve
from the small cylinder and the other valve serving as an admission or distributing
valve to the large cylinder. These two valves are worked from two separate
excentrics upon the main shaft. The cylindrical valve chambers are preferably
provided with linings, and the moveable covers at each end can be readily
removed for getting access to or taking out the valves. For valves, of the kind
described, of considerable diameter, we prefer to use packing rings of any of the well
known forms, but for smaller ones we make them to fit the cylindrical chambers
sufficiently tightly without packing rings. One or more openings may be made
vertically through the cylindrical cut-off valves, or in the side of the chamber in
which they work, to allow the escape of any condensed water which may have passed
into the ends of the chamber outside the valves.
We make the exhaust valves from the large cylinders, preferably in the form of
cylindrical pistons working in a corresponding cylindrical chamber, close to the
exhaust ports at the ends of the cylinder which pass straight into the chamber, the
cylindrical valves being fixed upon a spindle and the exhaust pipe communicating
with the chamber between them.
The valve spindle passes through a stuffing box and is worked by a separate
excentric upon the shaft. One or more openings may be made through the valves, in
the manner just described for the escape of any condensed water.
The movement of the exhaust valves from the large cylinder may be so regulated
as to allow of the exhaust at any part of the stroke, as may be desired.
Instead of working the valves by means of excentrics the motion may be used of
a lever or set of levers worked from the connecting rod, or other means may be
employed for the purpose.
We prefer to cast the several cylinders as well as the valve chambers, ports, and
passages, in one piece for small engines, making one joint for larger sizes, so that the
outside surface is exposed as little as possible to loss of heat and condensation by
radiation, and we cover the whole with asbestos or other suitable non-conducting
material as a protection against such radiation.
Instead of two cylinders only as described, three or more may be used, each
succeeding one being of properly increased diameter, so as to form triple or multiple
expansion engines to any desired extent, the different valves being worked by suitable
excentrics or other means. The engines may be arranged in any convenient position
and the details may be varied more or less according to the conditions and circum-
stances under which they are to be used.

page_text: COMPLETE SPECIFICATION.
Improvements in Steam Engines.
We, WILLIAM HENRY ALLEN, RICHARD WRIGHT, and RICHARD WILLIAM ALLEN,
Engineers, of York Street. Works, Lambeth, in the County of Surrey, do hereby
declare the nature of this invention and in what manner the same is to be
performed, to be particularly described and ascertained in and by the following
statement and accompanying drawing, that is to say :-
Our invention relates to steam-engines in which steam at a sufficiently high pressure
is admitted to a cylinder containing a piston, after actuating which the steam passes
to a larger cylinder in which it continues to do useful work while expanding, and in
some cases subsequently passes to one or more still larger cylinders.
Our invention is applicable more especially to that form of such compound, triple,
or quadruple, engines in which double-acting cylinders are arranged side by side, the
pistons operating by means of connecting rods directly upon cranks arranged either
opposite to each other or at other angles upon the shaft.
In such engines as ordinarily heretofore 'made, the steam is first admitted into a
steam chest where it is distributed by means of an ordinary slide valve to the
smallest or high pressure cylinder where (after usually having been expanded to some
extent) it passes back through the exhaust port to the slide valve, and through the
latter to an external eduction pipe which conducts it to the steam chest of the larger
or low pressure cylinder into which it is admitted by another slide valve, and after
having completed its expansion passes away through the exhaust pipe to a condenser
or discharge.
In this method of arrangement the steam both at its higher pressure and after
expansion, passes through the same valve, a considerable loss resulting from the
reduction in heat, and from the external eduction pipe, whilst the ports or passages
are necessarily of considerable length and size and it is impossible, both on this
account and on account of the condensation arising from the causes mentioned, to
obtain a high efficiency.
Our present invention has for its objects improved methods of constructing and
arranging such engines so that the objections described are overcome and the enginos
are very efficient, compact, and durable.
In the accompanying drawings
Figure 1 is a longitudinal section through a steam-engine constructed according to
our invention and having two cylinders.
"
Figure 2 is a horizontal section through the line A-A, Figure 1, and
Figure 3 is a horizontal section through the line B-B, Figure 1.
We admit the steam to the smaller or high pressure cylinder a by means of a
valve bbwhich is not used as an exhaust valve, but simply as an admission and cut-
off valve, working close to the ports c c at the ends of the cylinder a.
The valves bb
are preferably cylindrical and of sufficient diameter and length at each end of the
valve spindle d and working in corresponding cylindrical chambers e e parallel with
the bore of the cylinder a and as close to it as possible so that the ports may be as
short as possible.
Steam is admitted from between these cylindrical valves bb, which are actuated
by an excentric or equivalent device arranged in the ordinary way so as to open the
parts cc alternately at or somewhat before the beginning of each stroke of the
piston a¹ and to cut off the steam at any determined point of such stroke. As
the exhaust steam does not pass through these valves the initial heat of the steam
is maintained.
The steam is exhausted from the cylinder a through two separate ports g g₁
preferably opposite to the admission ports c c', these exhaust ports y g' being carried
in the usual way to near the centre of the cylinder a where they enter a chamber in
which works a cylindrical valve i between the smaller high-pressure cylinder a and the
adjoining larger low-pressure cylinder k. This cylindrical valve i serves both as an
eduction valve to the smaller cylinder a and as an admission or distributing valve to

page_text: the larger cylinder k, the ports of which are made as short as possible and pass
direct from the cylindrical valve chamber h to the ends of the cylinder k.
The cylindrical valve i is made hollow, suitable ports being made through its sides
which serve as eduction ports from the smaller cylinder a, and others which serve as
admission ports to the larger cylinder & as shewn, these several ports being arranged
so as to open and close the several openings or ports g, g', l, and 1, at the right
times.
The passages
from the central valve i open into a chamber m, Figures 2 and 3,
communicating with the ports to the cylinders, and this chamber m may serve as a
receiver between the two cylinders a and k, and is preferably steam jacketted.
In the case of engines having their cranks opposite to each other the receiver m
may if desired be entirely dispensed with, the central valve i acting as an inlet and
an outlet valve direct, without a receiver.
The valve i is provided with a valve spindle n actuated by a separate excentric in
the usual way.
In the case of large engines constructed according to our invention, we prefer to
use two separate cylindrical valves instead of a single one only as described and
shewn. In such case we make two separate cylindrical chambers side by side, each
containing a cylindrical valve, one of which serves as an exhaust valve from the
smaller cylinder and the other as an admission or distributing valve to the larger
cylinder.
These two valves are worked from two separate excentrics upon the main shaft.
The cylindrical valve chambers are preferably provided with linings as shewn,
having openings through them in the proper positions, and the moveable covers o o at
each end can be readily removed for obtaining access to or for taking out the valves.
For valves of the kind described of considerable diameter, packing rings of any of
the well known forms may be used, but for smaller ones we prefer to make them fit
the cylindrical chambers sufficiently tightly without packing rings. One or more
openings or passages may be made vertically through the cylindrical valves, or in the
side of the chambers in which they work, in order to allow the escape of any condensed
water which may have passed into the ends of the chamber outside the valves.
We make the exhaust valves from the larger cylinder k, preferably in the form of
cylindrical pistons p p working in corresponding cylindrical chambers close to the
exhaust ports ss at the ends of the cylinder, which ports pass straight into the
chambers rr,
the cylindrical valves p p being fixed upon a spindle t, and the exhaust
pipe at u communicating with the chamber v between them.
The valve spindlet passes through a stuffing box, and is worked by a separate
excentric upon the shaft.
One or more openings may be made through the valves p p, in the manner already
described, for the escape of any condensed water. The movement of the exhaust
valve p p may be so regulated as to allow of the exhaust at any part of the stroke of
the piston kas may be desired.
Instead of the several valves being worked by means of excentrics they may be
worked by a lever or set of levers driven by the connecting rod, or other ordinary
well known means may be employed for the purpose.
We prefer to cast the several cylinders as well as the valve chambers, ports, and
passages, in one piece for small engines, or with one joint between them for larger
sizes, so that the outside surface is exposed as little as possible to loss of heat and
condensation by radiation, and we cover the whole with asbestos or other suitable
non-conducting material as a protection against such radiation.
Instead of two cylinders only as described, three or more may be used, each
succeeding one being of properly increased diameter, so as to form triple or multiple
expansion engines to any desired extent, the different valves being worked by suitable
excentrics or other means.
The engines may be arranged in any convenient position, and the details may
be varied more or less according to the conditions and circumstances under which
they are to be used.

page_text: Having now particularly described and ascertained the nature of our said inven-
tion, and in what manner the same is to be performed, we declare that what we
claim is :-
1. The combination of a high pressure cylinder, a separate steam admission and
cut-off valve, a low pressure cylinder, a cylindrical valve serving both as an exhaust
valve from the high pressure cylinder and an admission valve to the low pressure
cylinder, and a separate exhaust valve from the low pressure cylinder, all arranged
and operating substantially as described and shewn in the drawings.
2. The combination of a high pressure cylinder and separate steam admission and
cut-off valve, a low pressure cylinder, and two separate cylindrical valves between the
high pressure and the low pressure cylinders, one valve serving as an exhaust valve
for the high pressure cylinder and the other valve as an admission valve to the low
pressure cylinder, and a separate exhaust valve from the low pressure cylinder, all
arranged and operating substantially as described and shewn.
3. Where three or more cylinders are used, the cylindrical valves between the
cylinders serving as exhaust valves from the smaller cylinders and as admission valves
to the next larger cylinders, substantially as herein described.
4. The combination with the several high and low pressure cylinders, and
cylindrical valves, arranged and operating as described, of the chambers in which
the several valves are contained, arranged and operating substantially in the manner
and for the purpose described and shewn.
Dated this fith day of Santambor 1900
EDWARDS & Co.,
35, Southampton Buildings, Chancery Lane, London, Agents for the Applicants.