Improvements in Compound Steam Engines and in Valves Employed therein.
Year: 1887

page_text: Date of Application. 15th Mar., 1887
Complete Left, 26th Nov., 1887
Complete Accepted, 27th Dec., 1887
Improvements in Compound Steam Engines and in Valves
Employed therein.
I THOMAS JOSEPH SIMMONS of East Peckham in the County of Kent Tanner do
hereby declare the nature of the said invention to be as follows:-
This Invention relates more particularly to a peculiar construction and arrangement
of compounding valve for compound steam engines whereby I obviate the loss of heat
in the live steam resulting from the passage of the exhaust steam through the live
steam ports and distributing valve or valves of the higher-pressure cylinder the exhaust
steam being caused to pass through a separate hollow compounding stide valve and set
of ports direct into and through the lower-pressure cylinder or cylinders.
My improved compounding slide valve is made hollow and is by preference of
cylindrical form either open or closed at both ends, it works in a corresponding valve
chamber situate between the higher and lower-pressure cylinders of the engine and
may be actuated by a valve spindle or connecting rod worked by an eccentric or other
suitable or well known mechanical arrangement. This hollow compounding slide
valve is provided with two sets of either single or double ports or openings disposed
by preference on the opposite sides thereof and communicating direct with corre-
sponding ports in the higher and lower-pressure cylinders respectively. The live
steam may be admitted to each end of the higher-pressure cylinder alternately by
any well known arrangement of slide or other distributing valve worked in the usual
manner. The exhaust from either end of the higher-pressure cylinder passes direct
by separate exhaust passages through the lateral opening or openings in the hollow
compounding slide valve to the corresponding end of the adjoining lower pressure
cylinder. The exhaust from the lower-pressure cylinder is either allowed to escape
through a separate exhaust valve or to enter a still lower-pressure cylinder by a hollow
compounding slide valve of the same description as that already given situate between
the first and second lower-pressure cylinders where more than one of such cylinders
is employed. If desired the compound engine may be so arranged that the higher-
pressure cylinder will be situate between two lower-pressure cylinders in which case

page_text: one of my improved compounding slide valves will be disposed on each side of the
higher-pressure cylinder that is to say between it and the two adjoining lower
pressure cylinders. In this arrangement the higher-pressure cylinder will be double
acting and the two lower-pressure cylinders single acting the exhaust steain from
either side of the higher-pressure piston passing direct through the said compounding
valves to the upper or under sides of the pistons of the lower-pressure cylinders. Or
the first described arrangement may be duplicated by disposing a pair of higher-
pressure cylinders between two lower-pressure cylinders with which they communicate
direct through corresponding compounding hollow slide valves.
Dated the 15th day of March 1887.

page_text: between the first and second lower pressure cylinders d and d' where more than one
of such cylinders is employed and so on.
When the steam is allowed to expand from the first lower pressure cylinder into a
second one the diameter of the second lower pressure cylinder d¹ and the dimensions
of the corresponding second compounding valve a' or the dimensions or number of
ports in such valve and corresponding cylinders should be proportionately increased
and SO on for any number of lower pressure cylinders as will be readily
understood.
In figure 3 for example 1 have shown the steam passages of cylinder d twice the
size of the steam passages of cylinder c and the second compounding valve a' as twice
the size of the valve a.
I and m are the pistons of the higher and lower pressure cylinders respectively.
When the inlet port for live steam is open to the upper side of the piston the upper
ports in the compounding valve are closed and the lower ones which communicate
for the time being with the underside of the piston ? are open to allow the exhaust
steam to pass directly below the piston m of the lower pressure cylinder or vice versa
according to the positions of the pistons and so on through the succeeding
compounding valves and lower pressure cylinders.
If desired the compound engine may be so arranged that the higher pressure
cylinder will be situate between two lower pressure cylinders in which case one of
my improved compounding slide valves will be disposed on each side of the higher
pressure cylinder that is to say between it and the adjoining lower pressure cylinder
on each side thereof. In this arrangement the central or higher pressure cylinder
will be double acting and supplied with live steam by any ordinary distributing valve
of its own whilst the two lower pressure cylinders will be single acting only the
exhaust steam from either side of the higher pressure piston passing direct through
the said compounding valves to the upper or under sides of the pistons of the lower
pressure cylinders. Or the first described arrangement (figure 3) may be duplicated
by disposing a pair of higher pressure cylinders between two lower pressure cylinders
with which they respectively communicate directly through corresponding
compounding hollow slide valves.
Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed I declare that what
I claim is
1. In a compound steam engine the employment of a separate hollow compounding
valve and sets of ports through which the exhaust steam passes directly from the
higher to the lower pressure cylinder substantially as specified.
2. In a compound steam engine the use in combination with the distributing valve
of the higher pressure cylinder of one or more separate tubular or hollow com-
pounding slide valves containing two sets of lateral ports or openings and working
111 a valve chamber or chambers having corresponding ports in direct communi-
cation with the adjoining higher and lower pressure cylinders respectively substantially
as specified.
3. The tubular or hollow compounding slide valve provided with two sets of lateral
ports or openings substantially as specified and illustrated by the accompanying
drawings.
Dated the 25th tree of L 1007