Year: 1887

page_text: Date of Application, 11th Mar., 1887
Complete Left, 17th Nov., 1887
Complete Accepted, 20th Dec., 1887
I ALFRED VINCENT NEWTON of the Office for Patents, 6 Bream's Buildings,
Chancery Lane in the County of Middlesex, Mechanical Draughtsman, do hereby
declare the nature of this invention to be as follows :-
The object of this invention is to devolop and utilize in a compound steam engine,
as far as possible, the mechanical energy contained in a given quantity of steam.
In order to attain this object, a modified arrangement of the compound engine
having the high and low pressure pistons on the same rod, is employed.
The high and low pressure cylinders, set end to end, either in a horizontal or
vertical position, are connected together at their adjacent ends by a steam passage
controlled by a cut-off valve.
The steam for working the engine is admitted from the boiler to the back of the
high pressure piston, and when it has acted fully thereon, communication is opened
with the low pressure cylinder, to allow of the partially exhausted steam acting upon
the piston of that cylinder.
The pistons of these cylinders are single acting. As the high pressure piston is
advanced under pressure of the incoming steam, any air, vapour, or water in front
of that piston will be expelled from its cylinder through an opening closed by a
valve, which opens outwards, and is closed by the atmosphere on the recession of the
piston.
When this piston has completed its stroke, the passage leading to the low pressure
cylinder is opened, and the partially exhausted steam then passes to the back of the
low pressure piston, driving it forward to the end of its stroke.
During this movement, the vacuum created in the high pressure cylinder will tend
to hold back the high pressure piston against the propelling force of the steam in the
low pressure cylinder, but the vacuum thus created will be utilized on the return
notion of the high pressure piston.

page_text: The opposite ends of the low pressure cylinder are brought into communication with
each other, and also with the condenser, by a passage controlled by a cut-off valve at
the inlet side of the cylinder.
As the low pressure piston completes its stroke, this cut-off valve is opened, and
the pressure of the steam being instantly equallized on the opposite sides of the
piston, no resistance will be offered to the return stroke of the high pressure piston,
to effect which, a fresh supply of steam is admitted to the high pressure cylinder.
This arrangement of compound engine, besides possessing the advantage of
simplicity of construction in respect of its steam passages and valves (there being but
three ports controlled by valves), avoids back pressure to the high pressure piston,
and ensures the low pressure piston being placed in equilibrio during the working
stroke of the high pressure piston.

page_text: Improvements in Compound Steam Engines.
I ALFRED VINCENT NEWTON of the Office for Patents 6 Bream's Buildings,
Chancery Lane in the County of Middlesex, Mechanical Draughtsman, 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:-
In
The object of this Invention is to develop and utilize in a compound steam engine,
as far as possible, the mechanical energy contained in a given quantity of steam.
carrying out this invention, the engine is constructed with two cylinders only, the
said cylinders being arranged so that their pistons, which are secured to or connected
with the same piston rod, will receive the pressure and expansive force of the steam
on one side only. Thus, each cylinder, and consequently its piston, are only single
acting. The invention consists in certain novel combinations hereinafter described
and claimed, of which such two cylinders and pistons constitute essential parts,
whereby, during the entire stroke produced by the action of the steam upon the smalĺ
or high pressure piston, the large or low pressure piston is made to work in equilibrio,
and whereby, at the same time, the small or high pressure piston may be made to work
against a vacuum.
Fig. 1 in the accompanying drawing is a side view of the principal parts of a
horizontal compound steam engine embodying the invention, the parts not necessary
to illustrate the invention being omitted. Figure 2. is a longitudinal sectional view
corresponding with Figure 1, except that it represents the crank in another position,
and the pistons moving in the opposite direction. Figure 3 is a longitudinal sectional
view, on a larger scale, of the cylinders and pistons, and the ducts and valves of the
said engine, the pistons and valves being in position, corresponding with the position
of the crank in Figure 1.
Similar letters of reference indicate corresponding parts in all the figures.
A, designates the small or high pressure cylinder of the engine, which receives
steam directly from the boiler. A', designates the large or low pressure cylinder into
which steam is pumped from the small cylinder, A, by the piston of the latter. The
two cylinders are arranged end to end in line centrally with each other and as close
together as is practicable, but entirely separate from each other, except that there is
provided between them a steam duct and a valve, as hereinafter described, and there
is also provided between them the stuffing box, C, with metallic packing for the
passage of the piston rod, D, on which are secured the small and large pistons E, E',
which are fitted respectively to the small and large cylinders. The said cylinders are
fitted at their outer ends with tight heads; and in one of the said heads, that of the
large cylinder in the example represented, there is a stuffing box, F, for the passage
of the piston rod, D.
Between the adjacent ends of the two cylinders there is a duct, a, which being at
the bottom of the small cylinder, and communicating with the large cylinder through

page_text: the end thereof, is very short; and within this duct there is a valve seat, b, for a
valve, c, represented as a simple flat sliding plate, for opening and closing commu-
nication between the two cylinders. At the same end of the small cylinder, A, there
is a duct, d, with which is connected the steam pipe, s, from the boiler, and in this
duct is the seat, e, for a valve, f, which, like, c, is also represented as a simple flat
sliding plate, the said valve, f, serving to admit steam from the boiler to the said
cylinder, A, and cut it off therefrom.
At the outer end of the small cylinder, A, there is an outlet pipe, g, which may
open to the atmosphere, or may communicate with the condenser, G, as shown in
Figure 1. At the connection of this pipe, g, with the cylinder, A, there is a valve, h,
which is arranged to close inwards, but will be forced open by excess of pressure on
its inner side.
The large cylinder has at its inner end, that is to say, the end next to the small
cylinder, and in valved communication therewith, as described, a second or outlet
duct, i, for communication with one of the branches of a pipe, H, leading to the
condenser, G, and in this duct there is a seat, 1, for the valve, j, which, like, c, and, f,
is represented as a flat plate sliding on its seat. At the outer end of the cylinder there
is a duct or port, at, k, which is always open to the condenser through a branch of the
pipe, H.
The bores of the two cylinders, and the surfaces of the pistons, will have a relative
area according to the intended degree of expansion of the steam, by which also the
point in the stroke of the small piston, at which the steam from the boiler is to be cut
off in the small cylinder by the valve, e, will be in part determined.
The valves may be operated by any known or suitable valve gear, such as is used
for working the valves of steam engines, and will therefore require no detailed
description. I will, however, trace the movements of the valves in describing the
operation of the engine, which is as follows:-
Suppose the pistons to be first at the right hand end of their stroke, and close to
the corresponding ends of their respective cylinders: the induction valve, f, is now
open or opening to admit steam to the right hand end of the small cylinder, A, to act
upon the corresponding face of the piston, E, and move it and the rod, D, to the left,
the valve, c, between the cylinders being closed, and, the valve, j, between the lef
hand end of the large cylinder and the condenser being open, all as shown in Figure 3.
When the valve, f, has been closed to cut off the supply of steam from the boiler tó
the small cylinder, the steam remaining in the latter continues by its expansive force
to act upon the small piston, and move it, and the rod, D, to the left, the valve, c,
remaining closed, and the valve, j, remaining open. By this, its first working stroke,
the said piston, E, expels all air from its cylinder, A, through the valve, h, and
pipe, g, so that on its return stroke, during which the valve, h, is closed, the said
piston produces a vacuum in its cylinder, and hence, during its second and all its
succeeding working strokes, the said piston works against a vacuum, which, if it should
not have been made perfect by the first working stroke and return, must be perfected
by the repeated strokes, and can never be lost.
While the small piston is thus working against a vacuum, the large piston must
move with it, and is in equilibrio, for the valve, j, being open, there is free commu-
nication through its duct, i, and thence through the duct, k, which is always open
between the two ends of the large cylinder. Hence, there is no resistance whatever
offered to the small piston during its working stroke, except such as is unavoidably
produced by friction.
At the end of the stroke of the two pistons and the piston rod to the left, the
valve, c, is opened, and the valve, j, is closed, so that communication is opened between
the adjacent ends of the two cylinders, and at the same time the working end of the
large cylinder is closed to the condenser, as shown in Figure 2, the other end of the
latter cylinder being always open to the condenser. The two pistons and their rods
are then caused to be moved to the right by the great excess of pressure of the steam
admitted from the smaller cylinder to the left hand face of the large piston, due to
the vastly greater area of that piston as compared with that of the piston in the

page_text: smaller cylinder. In this movement, which is the working movement of the large
piston, the latter works against a vacuum as perfect as inay be obtained in the
condenser.
The working stroke of the large piston having been completed, on the valves,
and, j, being opened, and the valve, c, being closed, steam from the boiler is again
admitted to the small cylinder to re-produce the working stroke of its piston, as before
described, while the face, or left hand side of the large piston, is completely relieved
of pressure through the duct, i, which is opened by the valve, j. This perfect relief
of pressure on the large piston is not delayed, as in the case of a simple condensing
engine, until the condensation of the steam in the condenser has been completed, but
on the instant of the opening of the valve, j, the said relief is effected by the free
passage of the steam through the ducts, i, and, k, from the front to the back of the
large piston.
In the operation of this engine, the small piston, as may be understood from the
foregoing description, has three functions, viz: (1) that of a working piston; (2) that
of an air-pump-piston, to produce a vacuum in its own cylinder; and (3) that of a
steam-pump-piston to pump out the steam from its own cylinder into the large cylinder,
assisted, of course, by the expansive action of the steam.
It has been herein before stated that the pipe, 9, may be open to the atmosphere, or be
in communication with the condenser. It is represented as communicating with the
condenser, but so far as the working of the engine is considered, that is immaterial,
its purpose being to provide for conducting away the air and any steam that might be
forced out of the said cylinder, as herein before described by the air-pump-like
action of the piston, E, through the valve, h.-The said pipe also serves, by the
attendant simply feeling its exterior, to indicate whether or not the packing of the
piston, E, is in good order, for while there is no leakage around the said piston,
the said pipe will remain cool, but if there be such leakage, the said pipe will
become hot.
Among the merits of this engine, besides the absence of all back pressure against
the high pressure piston, and the low pressure piston being placed in equilibrio during
the working stroke of the high pressure piston, may be mentioned its freedom from
long steam passages and ducts, which involve so much loss in clearance and by
radiation, and the simplicity of its construction, and especially the simplicity of
the valve system, thero being but three valves, and those of the simplest known
kind, viz: mere flat plates working over simple ports without circuitous ducts or
passages.
All the merits above mentioned, except the entire absence of back pressure on the
small piston, would be retained if the pipe, g, were connected with the condenser, even
though the valve, h, should be omitted, and free communication should be allowed
between the outer end of the high pressure cylinder, and the condenser, through the
pipe, g. In that case, a constant vacuum, like that on the condenser, would be kept
up on the outer side of the piston.
The cylinders and pistons might be arranged in any position from vertical to
horizontal, but the horizontal arrangement represented, serves as well as any other
for illustration.
Having now particularly described and ascertained the nature of the said Invention
and in what manner the same is to be performed as communicated to me from
abroad, I declare that what I claim is:
1. The combination of the high and low pressure cylinders, arranged end to end, and
having a steam duct and valve for the same, between their adjacent ends, two pistons,
one for each cylinder, and a rod common to both pistons, a condenser, an open duct
through which the outer end of the low pressure cylinder is in direct and constant
communication with the condenser, a duct and a valve for the same between the inner
end of the low pressure cylinder and the condenser, and an outlet pipe to the
condenser, at the outer end of the high pressure cylinder, all substantially as herein
described.

page_text: 2. The combination with the high-pressure cylinder, and its steam-actuated piston,
and a valve for the induction of steam to the said cylinder at one end only, of an
outlet valve at the other end of the said cylinder, whereby the said piston is made to
work as an air-pump piston to expel air and steam from said cylinder, and thereby
cause a vacuum on one side of the said piston while the steam acts on the opposite
sido.
3. The combination in a compound steam engine of a high pressure steam cylinder
receiving steam at one end only, and having at the other end an outlet valve, a low
pressure cylinder, one end of which is in direct and constant communication with the
condenser, and the other end of which has valved communications with the high
pressure cylinder and with the condenser, all substantially as herein described,
whereby the high pressure piston, during its entire stroke produced by the direct
action of the steam upon it, works against a vacuum, and at the same time the
low-pressure piston is in equilibrio, as herein set forth.
Datod this 17th day of November 1887