CERTAIN IMPROVEMENTS IN STEAM AND OTHER ELASTIC FLUID ENGINES
Year: 1875

page_text: LETTERS PATENT to Robert Wilson, of the Firm of Messieurs
Nasmyth, Wilson, and Company, of Patricroft, near Manchester,
in the County of Lancaster, Engineer, for the Invention of
CERTAIN IMPROVEMENTS IN STEAM AND OTHER ELASTIC FLUID ENGINES
CERTAIN IMPROVEMENTS IN STEAM AND OTHER ELASTIC FLUID ENGINES
71

page_text: My improvements consist in an improved mode of working steam or
other clastic fluids expansively, which is effected by cutting off the
supply at any portion of the stroke of the engine, and which will ın
duc proportion give out the power required.
The supply and exhaust valves may be perfectly balanced or free
from acting pressure, which not only economises fuel but adds to the
safety in working as well as reducing to the minimum the wear and
tear of the valves and valve gear, and in order to obtain a more perfect
command over the supply and exhaust valves they may be worked
independently of each other.
In performing my Invention the cut-off apparatus may be attached
direct to the ordinary ball governor or to any other regulator, by which
the motion of the engine is so regulated that the same number of
strokes in a given time can be obtained, whatever the load may be or
however much the pressure of steam or other elastic fluid may vary, so
long as there is sufficient pressure for the load on the engine, and thus
not only securing the safety of the engine in case of accidents to the
machinery which the engine may be driving, but also great economy in
the materials operated upon when applied to manufacturing purposes, as
steady and uniform motion if of great importance in almost every
branch thereof.
In the present arrangement the spindles of the admission valves are
connected to a lever hung loose on the vibrating valve shaft, this lever
forms one piece with a segment on which the vibrating lever acts for
opening the admission valves, and to the same lever is cast or forged a
projecting lever to which the buffer or regulator for determining the
length of the stroke of the valve is attached. The vibrating lever 15
provided with a catch which connects it to the segment, and this catch
is disengaged by a cam or inclined plate on the vibrating shaft above
referred to. This cam or plate is acted upon by the governor or other
regulator, and releases the catch sooner or later, according to the power
required.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Robert Wilson in the Great Seal Patent Office on
the 20th January 1876.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, ROBERT
WILSON, of the Firm of Messicurs Nasmyth, Wilson, and Company, of
Patricroft, near Manchester, in the County of Lancaster, Engincer,
send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Twenty-first day of July, in the year
of our Lord One thousand eight hundred and seventy-five, in the
thirty-ninth year of Her reign, did, for Herself, Her heirs and suc-
cessors, give and grant unto me, the said Robert Wilson, Her special
license that I, the said Robert Wilson, my executors, administrators,
and assigns, or such others as I, the said Robert Wilson, my executors,
administrators, and assigns, should at any time agree with, and no
others, from time to time and at all times thereafter during the term.
therein expressed, should and lawfully might make, use, exercise, and
vend, within the United Kingdom of Great Britain and Ireland, the
Channel Islands, and Isle of Man, an Invention for "CERTAIN IMPROVE-
MENTS IN STEAM AND OTHER ELASTIC FLUID ENGINES," upon the condition
(amongst others) that I, the said Robert Wilson, my executors or
administrators, by an instrument in writing under my, or their, or one
of their hands and scals, should particularly describe and ascertain the
nature of the said Invention, and in what manner the same was to be
performed, and cause the same to be filed in the Great Scal Patent
Office within six calendar months next and immediately after the date
of the said Letters Patent.
NOW KNOW YE, that I, the said Robert Wilson, do hereby declare
the nature of my said Invention, and in what manner the same is to be
performed, to be particularly described and ascertained in and by
the following statement (that is to say)
-
This Invention consists in certain improvements upon the Invention
for which former Letters Patent were granted to me on the 12th April
1870, Number 1063.
My improvements consist in an improved mode of working steam or
other clastic fluids expansively, which is effected by cutting off the

page_text: supply at any portion of the stroke of the engine, and which will in due
proportion give out the power required.
The supply and exhaust valves may be perfectly balanced or free
from acting pressure, which not only economises fuel but adds to the
safety in working as well as reducing to the minimum the wear and
tear of the valves and valve gear, and in order to obtain a more perfect
command over the supply and exhaust valves they may be worked
independently of each other.
In performing my Invention the cut-off apparatus may be attached
direct to the ordinary ball governor or to any other regulator, by which
the motion of the engine is so regulated that the same number of
strokes in a given time can be obtained whatever the load may be, or
however much the pressure of steam or other clastic fluid may vary, so
long as there is sufficient pressure for the load on the engine, and thus
not only securing the safety of the engine in case of accidents to the
machinery which the engine may be driving, but also great cconomy in
the materials operated upon when applied to manufacturing purposes, as
steady and uniform motion is of great importance in almost every branch
thercof.
In the present arrangement the spindles of the admission valves are
connected to a lever hung loose on the vibrating valve shaft; this lever
forms one piece with a segment on which the vibrating lever acts for
opening the admission valves, and to the same lever is cast or forged a
projecting lever, to which the buffer or regulator for determining the
length of the stroke of the valve is attached The vibrating level is
provided with a catch which connects it to the segment, and this catch
is disengaged by a cam or inclined plate on the vibrating shaft above
referred to. This cam or plate is acted upon by the governor or other
regulator, and releases the catch sooner or later, according to the
required.
power
And in order that my Invention may be more fully understood
and cadily carried into operation, I will proceed to describe the four

page_text: is a plan in section of the same; and on Sheet 4 Figs 3, 4, 5, 6, 7, 8, 9,
and 10, are detached views of parts of my improvements.
In Figs 1 and 2 a. is the steam cylinder, and a', a', are grooves at
the ends of the cylinder for carrying off the condensed water through
the exhaust ports a³, a; b is the piston; c, the piston rod, d, the crank
shaft; e, the steam supply pipe to be provided with a shut-off valve,
f is the exhaust pipe leading to the condenser, and g is the governor.
The supply valves h, h, and the exhaust valves 2, 2, are made with back
plates ¹ and ¹ to counterbalance the pressure, or they may be made of
any other suitable construction. The supply valves are acted upon by
the plungers which pass through stuffing boxes in the casing of
the valve boxes, or by springs, or by plungers and springs combined, or
other equivalents. Upon the crank shaft d is fixed the eccentric d¹ for
working the slide valves / by means of the eccentric rod h³, the lever h*
and rod which is jointed to the lever k³, fixed to the axle k, and to the
crank shaft d, is also fixed the eccentric d³ which gives motion to the
exhaust valves 2 by the rod ³, lever and rod ³, which is jointed to the
lever fixed to the shaft , to which is also fixed the lever 18 connected
by links to the spindles of the exhaust valves 2, or the supply and
exhaust valves may be worked in any other convenient manner to suit
the particular class of engine
The parts above enumerated are made in the ordinary way, or in the
manner described in the Specification of Letters Patent granted to mo
on the 12th day of April 1870, Number 1063, and consequently form no
part of my present Invention. The spindle of each valve h is connected
by a link to one of the segments 7', shewn on an enlarged scale in Fig 3,
and Fig. 4 of Sheet 4, these segments are keyed on the axle k which is
supported in journals in the plate a³ and bridle a³, the plate a² is fixed to
the cylinder. The catches 7, see Figs 8 and 9, drop over one end of the
segments or into notches, and carry the segments with them when
required for opening the valves ; these catches are supported by the
double lever m keyed on the shaft k, but they are free to move up and
down in the said lever, the pin m³ passing through a slot in each catch
to prevent them rising too much. The catches are disengaged from
the segments by the cams or inclined plates n' on the levers 22, see
Figs. 5 and 6, loose on the shaft k, or on bosses of 3', as shewn in Fig. 8.
As soon as the catches are lifted or disengaged from the segments 1¹,
they allow the valves to be instantly closed by the pressure of the

page_text: steam upon the plungers ³, or by springs, or plungers and springs
combined as above referred to, but this action although nearly instan-
taneous does not produce any injurious shock, the momentum being
checked by the elastic buffors a¹, a¹, shown in Figs. 10 and 21, which
are connected to the levers of the segments y².
The time for releasing or liberating the valves must be varied
according to the load on the engine, or to the pressure of the steam, and
this is effected by the governor in the following manner:-The sliding
bush gå forming part of the governor acts on the elbow lever g³ con-
nected by a link to the lever 'fixed on the shaft. g, to which is also
keyed the lever 9" connected by the link p¹ to the lever p³, this lever is
fixed to the same shaft as the lever 7ª, at one end of which is a toothed
segment gearing into a corresponding segment on the lever . To the
levers 7, 7ª, are suspended the links ³ connected to the levers n, n, above
referred to.
The mode of operation is as follows, and the Drawing represents the
parts in the positions they occupy when the engine is working at the
speed required:-When a portion of the load is taken off, the speed of
the engine will be accelcrated and the governor balls will expand, thus
raising the sliding bush g² and the horizontal arm of the elbow lever g³,
thereby raising the levers n, n, by the links 78, and causing the cams or
inclined plates n³ in the said levers to disengage the catches sooner
than before, and thereby cutting off the steam carlier and reducing the
speed of the engine If the speed of the engine should be too much
reduced, the governor balls collapse and the contrary action takes place.
The action of the parts above described is so sensitive that the speed of
the engine will be kept nearly uniform, notwithstanding any variations
in the load and in the pressure of steam.
On Sheet 2 Fig 11 is an elevation, and Fig. 12 a plan, of a
horizontal high pressure and condensing steam engine, to which a
modification of my improvements is applied; in this instance I employ
two shafts / which are supported in the plate a² and bridles a³, a³.
The segments j', j', see Figs. 13 and 14, on Sheet 4, are keyed on the
shafts k, k, and the catches drop down over one end of the segments
or into notches, as before described. The lovers n, n, scc Figs. 15 and 16,
loose on the shafts k, k, are connected in a T groove at the end of the
link, which is connected to the governor, as before described.

page_text: this arrangement the buffer a² receives the momentum of the valve and
the force of the plunger and spring direct from the end of the plunger
instead of through the levers and rods, as before described.
Having thus stated the nature of my Invention, and described the
manner of performing the same, I wish it to be understood that I do not
intend to limit myself to the details given, as the same may be con-
siderably varied according to the peculiar class of engines to which they
are applied without departing from the peculiar character thereof, and I
claim,―
First. The general arrangements of the parts for working the valves 1
of engines actuated by steam and other elastic fluids, as shewn and
described.
Secondly. The use of the segments j¹ in lieu of the discs and toggle
joints described in the Specification of former Letters Patent granted to
mo on the 12th day of April 1870, Number 1063, before referred to.
Thirdly. The improved modes of connecting the supply valves to the
segments, and the apparatus for actuating and liberating the same, as
shewn and described.
Fourthly. The balanced supply and exhaust valves shown in Figs 2,
12, and 23, when combined and used in the manner described.
And, Fifthly The application of the improved buffers a' for checking
the momentum and determining the traverse of the supply valves, as
shewn and described.
2
In witness whereof, I, the said Robert Wilson, have hcrcto
set my hand and scal, this Nineteenth day of January, One 2
thousand eight hundred and seventy-six.