CERTAIN IMPROVEMENTS IN STEAM AND OTHER ELASTIC FLUID ENGINES
Year: 1870

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
PROVISIONAL SPECIFICATION left by the said Robert Wilson at the
Office of the Commissioners of Patents, with his Petition, on the
12th April 1870.
I, ROBERT WILSON, of the Firm of Messieurs Nasmyth, Wilson,
and Company, of Patricroft, near Manchester, in the County of
Lancaster, Engineer, do hereby declare the nature of the said Inven-
tion for "CERTAIN IMPROVEMENTS IN STEAM AND OTHER ELASTIC FLUID ENGINES,"
to be as follows:-
The object of my Invention is to effect great economy in fuel and to
obtain steady, regular, and uniform motion, which Invention is equally
suitable for marine and land engines of any size or power.
My improvements consist in working the steam or other elastic fluids
expansively, which is effected by cutting off the supply at any portion of

page_text: the stroke of the engine, and which will in due proportion give out the
power required. The supply and exhaust valves are 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 are worked
independently of each other.
In performing my Invention I attach the cut off apparatus direct to
the governor, and also to either a screw or hydraulic differential
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 manu-
facturing purposes, as steady and uniform motion is of great importance
in almost every branch thereof.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by tho said Robert Wilson in the Great Seal Patent Office
on the 11th October 1870.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, ROBERT
WILSON, of the Firm of Messieurs Nasmyth, Wilson, and Company,
of Patricroft, near Manchester, in the County of Lancaster, Engineers,
send greeting.
=
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Twelfth day of April, in the year of
our Lord One thousand eight hundred and seventy, in the thirty-
third year of Her reign, did, for Herself, Her heirs and successors,
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

page_text: 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 exccutors or
administrators, by an instrument in writing under my, or their, or
one of their hands and seals, 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 Seal
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) :—
The object of my Invention is to effect great economy in fuel, and to
obtain steady, regular, and uniform motion, this Invention is equally
suitable for marine and land engines of any size or power.
My improvements consist, first, in an improved mode of cutting off
the supply of steam or other clastic fluid at any portion of the stroke
of the engine within certain limits so as to work the steam or other
clastic fluid expansively, and which will in due proportion give out the
power required; secondly, in making the supply and exhaust valves
perfectly balanced, or free from acting pressure, which not only econo-
miscs 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; thirdly, in attaching
the cut off apparatus direct to the governor or to either a screw or
hydraulic differential 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 cases of accident 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 is of great importance in almost every branch thereof.
And in order that my Invention may be more fully understood
and readily carried into operation I will proceed to describe the

page_text: accompanying Sheet of Drawings, reference being had to the figures
and letters marked thereon.
Fig. 1 is an elevation of a horizontal high pressure and condensing
steam engine to which my improvements are applied; Fig. 2. is a plan
in section of part of the same; Figs. 3, 4, 5, 6, and 7, are detached
views of parts of my improvements.
In Figs. 1 and 2, a is the steam cylinder which is surrounded by a
steam jacket a¹ to prevent condensation; 6 is the piston; c, the piston
rod; d, the crank shaft; e, the steam supply pipe provided with a
shut off valve e'; f is the exhaust pipe leading to the condenser, and g
is the governor; the parts above enumerated are made in any approved
manner. The supply valves h, h, and the exhaust valves i, i, are made
with back plates and to remove the pressure and to balance the
valves in the manner described in the Specification of Letters Patent
granted to me on the Fifth day of September One thousand eight hundred
and fifty-six, No. 2070, and on the Fifth day of November One thousand
eight hundred and sixty-one, No. 2772, 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 shewn by
dotted lines in Fig. 1, the lever * and rod 75 which is jointed to the
lever fixed to the axle k, which will be described hereafter, and to
the crank shaft d is also fixed the eccentric d' which gives motion to
the exhaust valves by the rod, lever ", and rod which is jointed
to the lever i fixed to the shaft 7, to which is also fixed the lever ³,
connected by links to the spindles of the exhaust valves i, or the supply
and exhaust valves may be worked in any other convenient manner to
suit the particular class of engine.
My present Invention consists in an improved combination of
machinery for giving motion to the supply valves so as to work the
steam expansively by cutting it off at the required portion of the stroke,
and to regulate the cut off by the governor, and these operations are
performed by the following parts:-The spindle of each valve his
connected by a link ; to one of the discs 1, shewn on an enlarged scale
in Fig. 3, and in section in Fig. 4; these discs are loose on the axle

page_text: which is supported in journals in the plate a and bridle a fixed to the
cylinder casing. In each disc j' is a notch or recess into which the
points of the catches / enter; these catches are supported by the double
lever m keyed on the shaft k, and shewn in Figs. 4 and 5, but they are
free to move up and down in the said lever, the pin m passing through
a slot in each catch to prevent them rising or falling too much. The
catches are lifted out of the notches j' by the inclines on the levers n
loose on the shaft /, or on bosses of j', and shewn in Figs. 4, 6, and 7;
one of these levers, shewn in Fig. 6, is provided with a pointer and a
graduated segment is fixed to the plate a² to indicate the amount of cut
off. As soon as the catches are lifted out of the said notches the
discs being released allow the valves to be instantly closed by the
pressure of the steam upon the plungers ², or by springs, or plungers
and springs combined as above referred to, but this action although
nearly instantaneous does not produce any injurious shock owing to the
toggle joint formed by the link and disc coming into a straight line, as
shewn to the right of Fig. 1. 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 governor is driven by the shaft o, to which motion is
communicated by the crank shaft as usual, at the end of the shaft o is
fixed the bevel wheel o'. The wheel o' gears into the wheel g' fixed to
the shaft of the governor g, the wheel ' gears into the wheel p³,
the
boss of which revolves in a fixed bearing. The shaft p passes through
the boss of the wheel p, this shaft revolves in a fixed bearing p' and in a
hole in the end of the shaft o. To the shaft p is fixed the clutch box p¹
which takes alternately into clutches on the wheels o¹ and p². Upon the
shaft is also fixed the worm gearing into the tooth segment q, forming
part of or fixed to the lever q', this lever by means of the link q², elbow
lever, and rod is connected to the two elbow levers 7, and the horizontal
arms of these elbow levers are connected by the links 7 to the levers n.
The mode of varying the cut off by the governor is as follows:―The
sliding bush g forming part of the governor acts on the lever g³ from
which depends the weighted rod y', the lower end of which is jointed
to the horizontal arm of the elbow lever g', the vertical arm of which is
connected by a stud to the clutch box p' on the shaft p.
The mode of operation is as follows, and the Drawing represents the
parts in the positions they occupy when the engine is working below its

page_text: .
regular speed, and when the steam is cut off at the longest portion of the
stroke. At this time the clutch box p¹ is in gear with the clutches on
the wheel o, thereby turning the shaft p round, and causing the worm p³
to bring the end of the segment q against the stop q³, the motion of the
segment being thus arrested, and the shaft p still continuing to revolve.
The segment then acts as a nut for the worm p³, and the shaft pis moved
endwise in the direction of the arrow, thus drawing the clutch box p' out
of the clutches of the wheel o¹, and thereby stopping the rotation of the
shaft p; this motion of the clutch box p' moves the elbow lever ƒ³ and
raises the rod g, thus lifting the end of the lever g³ off the flange of the
bush g; the parts would remain in these positions until the speed of
the engine became too great. When the parts are in these positions
the inclines on the levers n are held back so as only to liberate the
catches after-the-greatest supply of steam has been admitted to the
cylinder, and this would continue until the speed of the engine exceeds
the desired limit. When such is the case the bush ŋ³ is raised by the
expansion of the governor balls until the flange reaches the end of
the lever g³, and as the bush g continues to rise it lifts the rod g*, thereby
acting on the elbow lever gs, and by moving the shaft pendwise throws
the clutch box p' in gear with the clutches on the wheel 2; the wheel p
now becomes the driver and turns the shaft p round in the contrary
direction; the end motion of the shaft p also acts on the elbow lever q',
and by it on the levers n, to bring the inclines into position for acting
sooner on the catches 1, thus liberating the discs and cutting off the
supply at an carlier point. So long as the clutch box p¹ is in gear
with the wheel p² the worm p³ continues to act on the segment q, and
by depressing the link q it continues to reduce the amount of supply
until the engine is brought back to the proper speed, at which time the
governor brings the clutch box 2' in its central position and out of gear
with both the wheels o¹ and p³, where it remains until another variation
in speed takes place.
In the engine above described the supply valves are worked in-
dependently of the exhaust valves, but in some cases they may be worked

page_text: Fig. S represents a modification of my improved differential cut off
gear. In this case the bush g of the governor y acts on the vertical
rack 8, the lower end of which is connected to the lever t, by which the
supply of water pressure is regulated to the cylinder u, which is provided
with a piston; the water is admitted alternately above and below the
piston by the action of the governor. The rack & gears into one side of
the pinion s, and the rack ' connected to the piston of the cylinder u
gears into the other side of the said pinion 8', which is mounted on a stud
fixed in the horizontal arm of the elbow lever 10, the vertical arm of which
is jointed to the rod connected to the cut off gear, as described in
reference to Fig. 1. By this arrangement the variations in the speed of
the engine effect the required variations in the cut off.
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
limit myself to the details given, as they may be varied according to
the peculiar construction of the engine to which they are applied, and I
claim,-
First. The general arrangement of the parts for working the valves of
engines actuated by steam and other clastic fluid, as shewn and
described.
Secondly. The mode of connecting the supply valves to the discs 1,
and the apparatus for actuating and liberating the discs, as shewn and
described.
Thirdly. The balanced supply and exhaust valves shewn in Fig. 2, and
described in the Patents granted to me above referred to, when combined
and used for the purposes set forth.
And, lastly. The improved differential apparatus connecting the
governor to the cut off gear as shown and described in reference to
Figs. 1, 2, and S.
In witness whereof, I, the said Robert Wilson, have hereunto set
my hand and scal, this Eighth day of October, One thousand
eight hundred and seventy.
DADTUM VTT SAV
ROBERT WILSON. (L.S.)