Improvements in Compound Steam Engines.
Year: 1892

page_text: Date of Application, 8th Feb., 1892
Complete Specification Left, 8th Aug., 1892-Accepted, 8th Oct., 1892
PROVISIONAL SPECIFICATION.
Improvements in Compound Steam Engines.
I, JOSEPH WRIGHT of 16 Great George Street, in the City of Westminster,.
Mechanical Engineer, do hereby declare the nature of my invention to be as
follows:-
My invention relates to steam engines, more especially to engines operating on
the compound principle, and has for its object to prevent the objectionable back
pressure and consequent "looping" in the indicator diagrams which occurs when
the supply of motive fluid is lessened. According to my invention I provide valves
or cocks (which may be of, or provided with a soft material to prevent noise)
between the steam space or passage to, and the exhaust space or passage from, each
cylinder, which valves or cocks open, or are opened, when the supply of steam is
lessened to such an extent that there is not sufficient steam to fill all the cylinders
so that in the low pressure cylinder or, low pressure cylinders, which is or are not
filled with steam communication is opened between the steam space or passage to,
and the exhaust space or passage from, that cylinder or those cylinders, and
objectionable back pressure and looping" are obviated by reason of the steam
spaces of the cylinder or cylinders being supplied from the exhaust side to make up
deficiency in steam received from the preceding cylinder or cylinders. This may
be done through the medium of the ordinary steam and exhaust ports or special
ports may be provided and attached to the cylinders for the purpose.
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My invention may be applied to any class of engine to which it is or may be
applicable but is especially adapted for such engines as are subjected to considerable
variation in load such as engines for driving dynamos, locomotives rolling mill
engines, and marine engines, whether they be condensing engines or not. The
valves which are provided as described may be lift valves operating automatically,
or they may be operated by hand, or by gear which is under control of the governor
or of the engine itself.
Datad this 8th day of Wahmane 1000
J. H. JOHNSON & Co.,
47, Lincoln's Inn Fields, London, W.C., Agents.
COMPLETE SPECIFICATION.
Improvements in Compound Steam Engines.
I, JOSEPH WRIGHT of 16 Great George Street, in the City of Westminster,
Mechanical 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 and by the following statement :-
My invention relates to steam engines operating on the compound principle, and
has for its object to prevent the objectionable back pressure and consequent
"looping" in the indicator diagrams of steam engines which occur when the supply
of steam is lessened and this I effect without air or dust or other foreign matter
passing into the cylinders. According to my invention I provide valves or cocks
(which if in the form of lift valves may be of, or provided with, a soft material to
prevent noise) between the steam space or passage to, and the exhaust space or
passage from, each cylinder, which valves or cocks open, or are opened when the
supply of steam is lessened to such an extent that there is not sufficient steam to fill
all the cylinders, so that, in the low pressure cylinder, or low pressure cylinders,
which is, or are, not filled with steam, communication is opened between the steam
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page_text: space or passage to, and the exhaust space or passage from, that cylinder, or those
cylinders, and objectionable back pressure and "looping" are obviated by reason of
the steam spaces of the cylinder or cylinders being supplied with extra steam from
the exhaust side of its own piston or their own pistons to make up deficiency in
steam received from the preceding cylinder or cylinders. This may be done
through the medium of the ordinary steam and exhaust ports or special ports may
be provided and attached to the cylinders for the purpose.
My invention may be applied to any class of compound steam engine to which
it is, or may be, applicable; but is especially adapted for such engines as are
subjected to considerable variation in load, such as engines for driving dynamos,
locomotives, rolling mill engines, and marine engines whether they be condensing
engines, or not. The valves which are provided as described, may be lift, or slide,
valves operating automatically, or they may be lift, or slide, valves, or cocks,
operated by hand, or by gear which is under control of the governor, or of the
engine itself.
The accompanying drawings represent what I consider the best arrangements
according to my invention, but I do not limit myself to the precise details shown.
Figure 1 is a sectional plan and Figures 2 and 3 are vertical sections, at right
angles to each other, of so much of a compound steam engine as is necessary to
shew the application of valves operating automatically according to my invention,
and
Figures 4 and 5 are a sectional plan, and sectional elevation, respectively, of an
arrangement wherein the valves are opened positively by the operation of the
governor.
I have illustrated an engine with three cylinders arranged with steam passages
to, and from, the cylinders as described in the Specification of my application for
Letters Patent No. 20777 of 1891, bui. I do not limit myself to the number and
arrangement of the cylinders and passages as shewn. S are the steam passages to
the cylinders and T are the exhaust passages therefrom. U are the valves, which,
when closed, cover openings in the division walls between the said steam and
exhaust passages.
When there is not sufficient steam received from a preceding
cylinder to fill the next one the valves U, appertaining to that cylinder, open and
exhaust steam passes from the exhaust side of the cylinder to make up the
deficiency on the steam side of the same cylinder without air or dust passing in
with the said exhaust steam.
I do not limit myself to any particular position in which to place the valves U,
or to the number of the valves employed, provided it, or they, is, or are, between
the inlet and exhaust steam passages. In dotted lines at U2, in Figure 2, I have
shewn for instance the valves arranged in another position.
In Figures 4 and 5 the rods of the valves U are connected by levers v with the
rod w of a governor driven by the engine so that the valves are controlled by the
said governor.
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 :-
In compound steam engines, a valve, or cock, or valves, or cocks, between the
inlet passage to, and the exhaust passage froin, the cylinder, or each of the
cylinders, or from one side to the other of the same piston, whether the said valve,
or valves, or cock, or cocks, be operated mechanically, or by the pressure of the
steam under the conditions mentioned; all substantially as, and for the purposes;
hereinbefore described, and illustrated by the accompanying drawings.
Dated this 8th dow of August 1000
J. H. JOHNSON & Co.,
Agents.