Improvements in Engines having Two or more Cylinders.
Year: 1896

page_text: Date of Application, 11th Aug., 1896
Complete Specification Left. 10th June, 1897-Accented 24th July 1897
PROVISIONAL SPECIFICATION.
Improvements in Engines having Two or more Cylinders.
We, ROBERT LUNAN WEIGHTON, of the Durham College of Science, in the Town
and County of Newcastle-on-Tyne, Professor of Engineering, and DONALD BARNS
MORISON, of Hartlepool Engine Works, Hartlepool, in the County of Durham,
Engineer, do hereby declare the nature of this invention to be as follows:-
Our invention has reference to improved constructions of engines in which the
valves of two or more cylinders working upon two cranks are actuated by one set of
valve gear, and also to particular arrangements and methods of balancing or relieving
the valves.
In the case of any two consecutive cylinders of a multiple expansion engine in
which the exhaust steam of the first is the supply steam of the second cylinder and
which cylinders work upon separate cranks, the valves being driven by one set of
valve gear, we arrange valves of the flat or slide type back to back in a common
chamber or receiver. Supply steam for the first cylinder is first admitted to the
central portion of its valve, the inside edges of the valve constituting the admission
and cut off edges, and the outside the release and compression edges: the valve of
the second cylinder is arranged in the reverse way the outside edges governing the
admission and ent off, and the inside the exhaust and compression. According to one
arrangement the valve of the first cylinder is kept up to the valve face on the cylinder
by extending the face of the valve so as to increase the area acted upon by the steam
pressure in the receiver and these extensions are or may be recessed on the face and
the recesses connected to any source of lower pressure, such as another receiver the
hotwell or the condenser.
The valve of the second cylinder is a flat or slide valve, the two valves being
suitably connected and driven by means of one spindle and one set of valve gear, and
their relative positions may be adjusted and maintained by springs or by other means
as may be found necessary, the steam passing from the first cylinder to the second
cylinder directly through the containing chamber or receiver.
The junction or connection between the two valves may take any of several
convenient forms, such as a stuffing box or flexible joint of any suitable character
with or without springs and the supply steam for the first cylinder may enter the
first valve either through a port on the first cylinder face, or through a port suitably
placed on the second cylinder face, thus passing through both valves on its way to the
first cylinder. Both valves are driven by means of suitable couplings or connections
by one spindle and one set of valve gear, and their relative positions may, if
necessary, be adjusted and maintained by springs or other suitable ineans.
We do not confine ourselves to using the slide valve with the extended face as
ereinbefore described in an engine in which two valves are driven by one set of
year, as such a valve being a balanced or equilibrium valve may be advantageously
ised in any design of engine independent of the nature of its driving gear.
TL-11

page_text: Improvements in Engines with Two or more Cylinders.
We, ROBERT LUNAN WEIGHTON, of the Durham College of Science, Newcastle-on-
Tyne, in the County of Northumberland, Professor of Engineering, and DONALD
BARNS MORISON, of the Hartlepool Engine Works, Hartlepool, in the County of
Durham, Engineer, 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 5
and by the following statement:-
Our invention has reference to improved constructions of engines in which
particular arrangements and methods of balancing or relieving the valves are adopted,
and in which the valves of two or more cylinders working upon two cranks are
actuated by one set of valve gear.
In the case of any two consecutive cylinders of a multiple expansion engine in
which the exhaust steam of the first cylinder is the supply steam of the second
cylinder, and which cylinders work upon separate cranks, the valves being driven by
one set of valve gear, we arrange valves of the flat or slide type back to back in a
common chamber or receiver. Supply steam of the first cylinder is first admitted to
the central portion of its valve the inside edges of the valve constituting the
admission and cut off edges, and the outside the release and compression edges; the
valve of the second cylinder is arranged in the reverse manner, the outside edges
governing the admission and cut off, and the inside edges the release and compression.
The valve of the first cylinder is kept up to the valve face on the cylinder by
extending the face of the valve so as to increase the area acted upon by the steam
pressure in the receiver, and these extensions are or may be recessed on the face and
the recesses connected to any source of lower pressure, such as to another receiver,
the hotwell or the condenser, and these extensions of the valve face may be inade
either vertically or horizontally or in both directions as may be found convenient in
particular cases. The valve of the second cylinder is a flat or slide valve, the two
valves being suitably connected together and driven by means of one spindle and one
set of valve gear, and their relative positions may be adjusted and maintained by
springs or by other means as may be found necessary, the steam passing from the
first cylinder to the second cylinder directly through the containing chamber or
receiver. We do not confine ourselves however, to using the slide valve with the extended
face in an engine in which the valves are driven by one set of valve gear, or in which
the cylinders act on separate cranks, as such a valve being a balanced or equilibrium
valve may be advantageously used in any design of multiple expansion engine
independent of the nature of its driving gear, for instance it may be used for any or
all of the cylinders of a multiple expansion engine (except for the low pressure
cylinder exhausting into a condenser), each valve being driven by separate valve gear,
and the cylinders may act on any number of cranks at any convenient angles.
In order that our invention may be fully understood we append two sheets of
explanatory drawings, Figs. 1, 2 and 3, showing in section three various constructions
of our balanced valve, whilst Figs. 4 and 5 show in elevation, part section, and in
plan, part section, respectively, an arrangement in which the valves of two consecutive
cylinders are driven by one set of valve gear. Fig. 6 illustrates in elevation a method
by which the valves illustrated in Figs. 4 and 5 are connected to enable them to be
driven by one spindle and one set of valve gear. The figures in all the drawings
correspond.
Referring to Fig. 1: the valve I is arranged with extensions 2, 2, which may be
provided with recesses 3, 3*, connected (by pipe or otherwise) to any source of lower
pressure, such as another receiver, the hotwell or condenser. We prefer that
communication between each of the recesses 3, 3" and the source of lower pressure

page_text: should be established by means of a passage formed through the valve face and a
fixed pipe connected thereto, but a passage might be formed for the same purpose
through the valve itself the connecting pipe in that case being attached to the valve
so as to move with it and being arranged to work through stuffing boxes where
necessary. Supply steam is admitted through the passage 4 and port 4°, to the
central portion 5 of the valve I, the inside edges 6, 6, forming the admission and
cut off edges, and steam enters the cylinder 7 through the ports 8, 8" in the usual
inanner.
The release and compression are controlled by the outside edges 9, 9ª, the exhaust
taking place through the ports 10, 10, into the chamber or receiver 7 It will be
seen that by means of the extensions 2, 2, the increased area of the valve I, acted
upon by the steam pressure in the receiver 7b, may be so arranged and adjusted that
the valve is relieved or balanced to any desired extent and retained in position on the
valve face 7"
Fig. 2 is a modification in which the extensions 2, 2ª, are arranged between the
ports of the valve I, steam supply being admitted through the passage 4, and
port 4 to the inside portions 5, 5, which correspond with the central portion 5, in
Fig. 1.
Fig. 3 is a further modification in which there is a single extension 2 of the
valve I, the inside portions 5, 5, corresponding with the central portion 5 in Fig. 1.
Steam supply is admitted through the passage 4 and ports on the cylinder face 4 4b
which correspond with the port 4 in Figs. 1 and 2.
Figs. 2 and 3 show two modifications embodying this invention, but it is evident
that various other modifications may be employed depending on the particular design
of engine to which they may be applied.
Fig. 4 shows an arrangement in which the valves of two consecutive cylinders of a
multiple expansion engine are driven by means of one set of valve gear, the
construction of the valve I of the first cylinder 7, being similar to that described
with reference to Fig. 1, steam exhausting into the receiver 7%, whence the second
cyclinder draws its supply.
The second cylinder 12 with its ports 13, 13ª, and valve face 14, takes steam in the
reverse manner, that is to say the outside edges 15, 15, of the valve 16 form the
admission and cut off edges, the inside edges 17, 17, governing the release and
compression, exhaust taking place through the central portion 18 and passage 19.
The relative positions of the valves 1, and 16, are adjusted and maintained by
springs 20, or other suitable means, the single spindle 21 forming the driving gear. "
For the sake of clearness in the drawings we have shown the valves as single
ported only, but it is obvious the ports may be increased to two or more, as desired.
We wish it to be understood that we do not claim as our invention the mere
driving of two valves for two separate cylinders by one set of valve gear, nor do we
claim a slide valve so arranged as to take steam into the inside of the valve, and
exhaust it at the outside, as we are aware that both of these arrangements have been
used, but what we do claim is as follows:-
1. An engine slide valve of the kind in which steam first enters the inside of the
valve and exhausts at the outside, having its face extended or made of enlarged area
so that the steam pressure in the receiver acting on the back of the valve and its
extensions, serves to maintain the face of the valve in its working position.
2. An engine valve of the kind referred to in the preceding claim in which the
extensions of the valve are recessed on the face, these recesses communicating with
a source of lower pressure, such as a second receiver, condenser, hotwell or
atmosphere.
3. Engine valves of the kind referred to in the preceding claims, constructed and
arranged as hereinbefore described with reference to and illustrated in Figs. 1, 2, and 3
of the accompanying drawings.
4. In a multiple expansion engine the combination of a valve constructed according

page_text: to any of the preceding claims, with a second slide valve to which it is flexibly
connected, both valves being driven by one set of valve gear substantially as
described with reference to and illustrated in Figs. 4, 5, and 6 of the accompanying
drawings.
is 10th day or
me 1897.
For the Applicants,
W. LLOYD WISE,
46 Lincoln's Inn Fields, London, W.C., Chartered Patent Agent.