IMPROVEMENTS IN STEAM ENGINES, BOILERS, AND METHODS OP PREVENTING ACCIDENTS IN WORKING THE SAME
Year: 1849

page_text: TO ALL TO WHOM THESE PRESENTS SHALL COME,. I, ROBERT
WILSON, of Low Moor Iron Works, Bradford, in the County of York, Engineer,
send greeting.
WHEREAS Her present most Excellent Majesty Queen Victoria, by Her
Royal Letters Patent under the Great Seal of Great Britain and Ireland, bear-
ing date at Westminster, the Seventh day of June, in the twelfth year of Her
reign, did, for Herself, Her heirs and successors, give and grant unto me, the
said Robert Wilson, my exors, adñiors, and assigns, Her especial license, full
power, sole privilege and authority, that I, the said Robert Wilson, my exors,
adñiors, and assigns, or such others as I, the said Robert Wilson, my exors,
adiiors, and assigns, should at any time agree with, and no other, from time to
time, and at all times during the term of years therein expressed, should and
lawfully might make, use, exercise, and vend, within England and Wales, and
the Town of Berwick upon Tweed, and in the islands of Jersey, Guernsey,
Alderney, Sark, and Man, and in all Her Majesty's Colonies and Plantations
abroad, my Invention of "IMPROVEMENTS IN STEAM ENGINES, BOILERS, AND METHODS
OP PREVENTING ACCIDENTS IN WORKING THE SAME;" in which said Letters Patent is
contained a proviso that I, the said Robert Wilson, shall cause a particular
description of the nature of my said Invention, and in what manner the same
is to be performed, to be enrolled in Her Majesty's High Court of Chancery
within six calendar months next and inmediately after the said in part recited
Letters Patent, as in and by the same, reference being thereunto had, will more
fully and at large appear..

page_text: NOW KNOW YE, that in compliance with the said proviso, I; the said
Robert Wilson, do hereby declare that the nature of my said Invention, and
in what manner the same is to be performed, are herein-after described and
ascertained, reference being had to the Drawings hereunto annexed and to the
letters and figures marked thereon, that is to say:-
My Invention relates,
Firstly, to a means of preventing explosions of steam boilers by the applica-
tion thereto of apparatus which, when the steam within the boiler attains an
undue pressure, discharges a portion of the water from the boiler upon the fire
in the fire-place, and thereby partially or wholly extinguishes the fire and
diminishes or suspends the further generation of steam within the boiler, and
which apparatus also, upon the decrease of the quantity of water within the
boiler, allows a current of steam to pass from the boiler to the fire-place and be
there discharged upon the fire, by which the fire is partially or wholly ex-
tinguished until a proper supply of water is provided in the boiler. My Invention
relates,
Secondly, to a peculiar construction of pistons for the cylinders of steam
engines and for other similar purposes, and to a peculiar construction of buckets
for air and water pumps of steam engines. My Invention relates,
Thirdly, to a mode of regulating and equalizing the movements of steam
engines by a peculiar construction of the governor, which, by its action upon.
any change of velocity of the engine, varies the connection between the governor
and the regulator valve, or varies the situation of the expansion cams. My
Invention relates,
Fourthly, to a peculiar construction of expansion valves, to render them more
perfect in their action. My Invention relates,
Fifthly, to a peculiar construction of the geering for giving motion to the slido
valves of steam engines, by which a variable movement is communicated to the
valve. My Invention relates,
Sixthly, to a mode of more effectually and quickly stopping the movements
of steam engines by the application of apparatus to the valve geering, which,
when the engine is required to be stopped, places the slide valve directly over
the ports, and thereby prevents further access of steam to the cylinder from
taking place. In the use of steam boilers with the ordinary apparatus attached
there is always great risk of an explosion, either from the exertion of an over
pressure of steam arising from the safety valve (with which the boiler is pro-
vided) sticking upon its seat or becoming otherwise out of order, or by being
overloaded; and, as is well known, the explosion of a boiler generally leads to
a great loss of life and property. Great risk of danger likewise arises from the

page_text: water within the boiler becoming so reduced in quantity as to leave uncovered
by the water portions of the flues or bottom of the boiler, by which such por-
tions so left uncovered become unduly heated by the fire, and by a reduction of
the pressure of the steam within the boiler by the quantity supplied to the steam
engine, or by discharge from the safety valve, violent ebulition takes place, and
the water flowing or pouring over the too heated portions of the boiler, steam
is rapidly generated, and the pressure within the boiler being suddenly increased
to a great extent, the safety valve is inadequate to discharge the surplus pressure
and explosion ensues. These results will sometimes occur even with the care
of the most experienced engineers.
When the ordinary apparatus is used, nothing but the greatest attention and
a knowledge and skill not always to be found among engine drivers will prevent
the constant occurrence of alarming accidents from explosion. Accidents more
frequently take place with that class of boilers known as low pressure boilers
than with high pressure boilers, and this is accounted for from the fact of the
high pressure boilers being superior in make and materials to those ordinarily
made for low pressure, and to the greater degree of care and attention bestowed
upon their management.
My plans or methods for preventing explosions are of the simplest kind, and
are regulated by the laws of nature, and their action is entirely independent of
attention or care on the part of the party in charge, acting rather like a watch-
man set over him to keep him to his duty; and however careless, ignorant, or
inattentive he may be, no accident can take place (if the apparatus is allowed
to act) by over pressure or by the water getting low in the boiler; this will
readily be seen by referring to the annexed Drawings, Figure 1.
It is a well known law in physics, that if any liquid is confined in a vessel,
such as a steam boiler, with a tube or pipe passing down through. the vessel,
with the mouth of the tube or pipe downwards and immersed in the liquid, and
if the surface of that liquid is pressed upon by any vapour, such as steam, the
liquid or fluid will rise in the tube or pipe to a height due to the pressure within
the vessel over and above that which is on the liquid in the pipe, and as the
pressure is raised or diminished, the liquid in the pipe will rise or fall in exact
proportion to the pressure on the fluid if open to the atmosphere, indicating
the pressure within the vessel above the atmosphere, which will continue so long
as there is sufficient liquid in the vessel to cover the mouth of the pipe. But
should the liquid be diminished so as the mouth of the pipe will no longer be
immersed, the liquid will drop partially into the vessel and partially be blown
out of the pipe (if the mouth be so open) by the force of the vapour within
the vessel, and allow the vapour. to escape freely, which is the principle on which

page_text: my low pressure boiler protector acts; to understand which more clearly, I refer
to Figure 1st, which is a longitudinal section of a steam boiler, with the pipe a
going down through the top of the boiler into the water, with the mouth open
downwards, and about one inch above the top of the furnace plates. This
boiler is a double flue boiler, with the furnaces inside of the flues, generally
known by the name of Cornish boilers, which are coming very much into use
on account of their superior form, for strength and economy in fuel, but perhaps
more liable than other boilers to the danger of getting short of water because
of their superior evaporating power; and hence the risk of their being injured
by getting red hot above the furnaces, and the greater damage they must cause
by an explosion from being short of water. The pipe a is not exposed to the
ebulitions or bubbles of steam which would go up through the water in the pipe
and cause it to boil, but is inserted into another piece of pipe b, open at top and
bottom, in which the water stands at the same level as in the other parts of the
boiler. The pipe a is carried up to that height from the surface of the water
that the column of water which runs in it will a little more than balance the
pressure upon the safety valve, say from half a pound to one pound per square
inch. To give the safety valve range enough for working freely without the pro-
tector coming into play, but except in cases of danger, by the valve sticking,
as before explained, near the top of the pipe a is a branch pipe c, which is
carried down and introduced to each of the furnaces (if more than one to each
boiler) above the furnace door. It will now be seen that if the pressure, by any
accident to the safety valve or otherwise, be raised above what it should be, the
water will rise in the pipe a to a height due to that pressure, and if that be such
as to raise the water up to the branch pipe c, it will immediately descend thro' the
pipe c into the furnace and damp the fire, which immediately reduces the pres-
sure by reducing the fire, the cause of the pressure, and thereby gives notice
that all is not right with the safety valve, or that there is more steam being
generated than is required.. The same thing takes place, but in a more decided
manner, when the water gets too low in the boiler, whatever the pressure may
be at the time; for if the water sinks below the mouth of the pipe a (being put
down to the lowest point of safety) the water will either drop out of the pipe or be
driven upwards by the steam. And as the pipe a is closed at the top (except a small
air hole to prevent the pipe c acting as a syphon) the steam, or rather steam and
water, descends the pipe'c and in a few seconds extinguishes the fire before the
boiler can possibly be injured or any accident arise; and by simply supplying the
proper quantity of water again, the furnace can be re-lighted and work as before.
And as there is in the apparatus nothing but a simple open pipe, without valves,
levers, or any mechanical contrivances, it can be arranged with the greatest ease,

page_text: and entire dependance may be placed on its action independent of care or atten-
tion on the part of the person in charge. For high pressure boilers, where a
high chimney exists to support the pipes, the same arrangements may be carried
out, as all that is wanting to be known is the height due to the pressure required,
which is about 34 feet for each 15 lbs. per square inch.
But for high pressure
boilers, when not sufficient height of chimney exists to support the pipes, I pro-
pose to use a column of mercury, to be affected by the pressure on the same
principle but requiring a different arrangement, and a small valve instead of the
common open pipe, which will be better understood by referring to Fig. 2, which
is a longitudinal section of a steam boiler of the same kind and construction as
that of Fig. 1, which is also often used for high pressure steam. d is a small
iron cistern filled with mercury, with a hole at top to allow the pressure of the
steam to act upon the mercury and cause it to ascend the small pipe e, which
is immersed in the mercury and goes up into another small cistern f in the close
box g, and into this small cistern f is the weight h, which nearly fills the cistern f.
The weight his attached to the lever i, which is again attached to the valve j,
so that when the pressure of steam is raised to a due point the mercury ascends
the pipe c, which is just of sufficient height for the pressure; but if raised above
the due pressure, the mercury then flows into the top cistern and floats the
weight h, which raises the lever i, and which again raises the valve and allows
the steam to escape into the box g, and from thence down the pipe k into the
furnace as before, which damps the fire and reduces the pressure.
And again,
if the water gets low in the boiler, the stone float will sink with the water
(being balanced at the proper depth immersed in the water), and as the float b
is hung from the lever m, which is also connected with the valve, the valve will
be raised thereby and the steam escape as before, and so reduce the fire as to
prevent it doing any injury to the boiler or to cause any accident to arise there-
from. My improvements in the steam pistons of steam engines consists in the
peculiar construction of the steam piston with metallic packing, which will be
better understood by referring to Figs. 3 and 4. a, the body; b, the cover of
ditto; c, c, the packing rings; d, the packing wedges; e, the spiral springs;
f, the adjusting screws; g, the keepers. This piston has peculiar advantages
over every other metallic piston, as it not only adjusts itself as the rings and
cylinder wears, but can be tightened up to any given intensity by the adjusting
screws f and the springe; and as these act upon the wedges d, which act
upon both rings c, c, and as the wedges are of such an angle as prevent
them jaming between the rings c, c, the rings c, c, are not only kept firm be-
tween the body and cover of the piston, but can slide forward or backwards
to meet any inequality in the cylinder by wear or otherwise. The ring is

page_text: cut inside with slitts s, s, to make it more easily bent by the action of the
springs e, e.
My improvements on the pump bucket are particularly applicable to the air
pump and cold water pump. It consists in making use of metallic packing,
which is self-adjusting, without screws or springs, which will be easily under-
stood by referring to Fig. 5, being a section of the bucket; and Fig. 6, a half
plan of the bucket. a, the body of the bucket; b, the lids; c, the metallic
packings; d, the packing ring; c, the guard. It will be seen by the section,
Fig. 5, that the body of the bucket where the packing segments c, c, rest is
slightly inclined, (being a little more than the angle of friction,) and as these
packings are first turned true in the form of a ring, and the bucket turned truc
fitting each other, the top edge being also inclined, but in a greater degree, the
packing ring d is made to fit. The packings are then cut into three or more
segments, and a piece let in below at each joint in the ordinary way, to cut the
joints. The top or packing ring d is kept whole, and as much less in diameter
as not to touch the working barrel when the bucket is working, and as the
bottom edge of the packing segments c, c, is inclined, and rests upon an incline,
(below the angle of friction, which is about one in five,) the segments when at
liberty will slide down the incline, and if in the inside of the working barrel will
rest against the side of the barrel; but in order that the top edge of the pack-
ing segments may rest against the working barrel also, the top edge is inclined
considerably inwards, and the packing rings d considerably outwards, to fit it;
and as this ring is whole and does not touch the working barrel, but rests with
its whole weight upon the packing segments, the segments are thus thrust
outwards against the working barrel, with the top edge also.
The packing
ring dis kept from rising further than is due by the guard e.
My improvements for regulating the motion of engines is applicable to all
stationary engines where the common governor is used. The object is to regu-
late it so that the engine will make the same number of strokes whether the
load be light or heavy, which is of the utmost importance in manufacturing
purposes. This I propose to do with the commion governors, which are made
to lengthen or shorten the throttle valve rod, as the case may require, or alter
the expansion valve cam where an expansion valve is used, which will be easily
understood by referring to the Drawing, Figs 7 and 8. a, the throttle valve
lever; b, the governor spindle; c, the arms; d, d, the balls; e, the links;
f, f, the sliding bush; f, f, the connecting rods; g, the tapet; h, the tapet
gab lever; i, the clutch; j, the clutch lever; k, the clutch lever shaft;
1, the governor, wheel; m the driving wheel; n, the loose wheel; o, the revers-
ing shaft.

page_text: In this case the governor acts upon the engine as in ordinary cases, by the
expansion or contraction of the balls d, when the engine goes faster or slower,
which contracts or increases the size of the opening for the ingress of the
steam, and which reduces or increases the quantity consumed, but instead of
the engine continuing to go faster or slower, as the case may be, by the
difference of the load or the pressure of steam, the governor thus expanded
or contracted brings into play another mechanical arrangement, by which the
quantity of steam consumed is still farther reduced or increased until such time
as the governor is brought exactly to the same position as desired, whatever
the load or pressure of steam may be. The governor is now shewn in the
position that it would be when the engine is at the proper speed, but should
the motion of the engine be changed by either the load or the pressure of steam
being changed, the balls d, will will be expanded or contracted, as the case may
be; should they be expanded by increased motion the slide bushes f, f,.will
rise, being connected to the arms c, c, by the links e, e, which will raise the
throttle valve lever a by the connecting rods f¹, f, and thus contract the
opening for the steam entering the cylinder in the ordinary way, but the rising
of the sliding bushes f, f, will also raise the tapet g, which will throw to one
side the gab lever h, and by it the clutch i will be thrown into gear with the
loose wheel n, and put in motion the shaft by the clutch i sliding upon a key
fixed in it in the ordinary way, and thus, by communicating the motion to a
valve rod for regulating the quantity of steam, the ingress will be decreased
and the motion of the engine decreased in proportion until the governor is
brought down to the proper position by the engine running again at the proper
speed; and if the reverse action takes place in the engine, namely, if it is
reduced in motion by increased load, or by the steam getting low, the reverse
action will follow, and the engine again be brought up to the proper speed;
this principal has been long applied to water wheels, but not to steam engines.
My improvement for the working of expansion valves is in the introducing
a piston or plunger, to be exposed to the pressure of the steam, to move the
valve in one direction, while the engine, by a cam or otherwise, moves it in the
other direction, instead of by a spring or by acting by gravity. Figs. 9 and 10:
a, the valve chest; b, the expansion valve; c, the piston or plunger, the upper
end of which is exposed to the pressure of the steam, and while the expansion
cam lifts or pushes it upwards, by acting against the rod below in the ordinary
way, by the eccentric sides of the cam and the pressure of steam on the top
ends, puts it down again whenever the eccentric side of the cam recedes again,
and thus, being in connection with the valve, carries it with it. This is the
same in principle as I have applied to the steam hammer. to work the ordinary

page_text: steam valve instead of springs, first used as described-in the Specification of a
former Patent.
My improvements in slide valve gearing consist in an arrangement of levers
for the purpose of obtaining a quick motion in the valve at a certain portion of
the stroke, by which means advantages are gained over the common eccentric
motion that I could not otherwise gain without having to travel the valve at
least a half more, which in many cases is impracticable, and still this is worked.
with the common crank or eccentric motion, gaining all the advantages of the
cam motion; see Fig. 11 and 12. a. the valve shaft; b and c, the compound
eccentric lever; d, the eccentric rod; e, e, the stop studs; f, f, f', the lever
stops. It will be seen that if the eccentric rod d be moved in the direction of
the arrow, the lever c having now come in contact with the stop stud e, the
lever b, which is fixed upon the valve shaft a, will now move twice as fast as
it did before the lever c came in contact with the stop stud e, for the lever has
not only been shortened, as it were, from the centre g to the centre h, but the
centre h has been increased to double its former motion by the lever c being
now converted from a lever of the first order to that of the third order, which
continues until the lever stop f comes in contact with the side of the lever b,
when the eccentric has now passed the centre, and the motion reversed, when
again the lever c is converted into a lever of the first order, or becomes part of
the lever b, which continues until again the lever c comes in contact with the
stop stud e, when again the slow motion is converted into the quick motion as
before, and this takes place just when the exhaust begins to open to the con-
denser.
I will now describe my improvements for stopping the engine quickly in case
of any accident; and by the means which I adopt the engine may be stopped
almost instantaneously by the most inexperienced person, and that without the
risk of any harm to the engine, and which will be easily understood by referring
to Fig. 13 and 14. a, the valve shaft; b, the eccentric lever; c, the eccentric
rod; d, the connecting link; c, the bridle rod; f, the bridle stud; g, the suspen-
sion rod. It will now be easily seen that if the valve shaft a is oscilating by
the vibration of the lever b, by the reciprocating motion of the eccentric rod c,
the valves will also move backwards and forwards, or upwards and downwards,
as the valve levers are fixed upon the valve shaft. But if the eccentric rod c
be suddenly dropped or lowered down (being suspended by the link. d, d, and
the suspension rod g, which latter is fixed to a small crank in the most con-
venient position to be got at readily, the eccentric rod being balanced in the
ordinary way, the link d, d, being in connection with the eccentric pin h,
and also connected to the bridle rod e, will slide down the eccentric pin h, and

page_text: bring the eccentric lever 6 under the command of the bridle rod c, and the
stud f being a fixture round which the bridle rod revolves, the eccentric
lever will be brought into the exact positions that will cause the valves to cover
up the steam ports, and thus prevent the engine from getting any more steam;
and the steam valves, if on the most improved plan in setting, will now be a
little open on the exhaust sides to the condenser, will allow the steam to escape
gently into the condenser, thus giving the fly wheel the whole work to do, will
make little more than one revolution. The injection .valve can be connected
to the same motion so as to be shut off at the same time.
Having now described the nature of my Invention, and in what manner the
same is to be performed, I desire it to be understood that I do not confine
myself to the precise details herein-before shewn and described, as modifications
to some extent may be made and other similar arrangements adopted for
effecting similar purposes without departing from the principles of my Inven-
tion; but what I claim as of my Invention is,-
Firstly, the causing water to be expelled from steam boilers and introduced
upon or amongst the burning fuel in the fire-place when an undue pressure of
steam takes place in the boiler, in order thereby to dimish .the intensity of, or
entirely to extinguish, the fire, and thereby lessen or entirely suspend the gene-
ration of steam and prevent explosion, as herein-before described.
Secondly, I claim the causing steam of any pressure above that of the atmo-
sphere to be discharged from steam boilers, and introduced upon or amongst
the burning fuel in the fire-place whenever the surface of the water within the
boiler descends to or falls below a certain level, in order to diminish the inten-
sity or entirely to extinguish the fire, and thereby prevent an undue heating of
the plates or materials of which the flues or bottom' of the boiler are composed,
and thus reduce the liability to explosion, as herein-before described.
Thirdly, I claim the construction and arrangements of pistons for steam
engines, namely, the adjustable wedges d, d, placed between and behind the
packing rings, as also the packing rings as herein-before described.
Fourthly, I claim the arrangement and construction of pistons or buckets for
air pumps and water pumps of steam engines, namely, the packing segments
with-bevilled or inclined edges, by which they are retained against the surfaces
of the cylinder or barrel without the aid of springs or other means, as herein-
before described..
+
Fifthly, I claim the regulating and equalizing of the velocity of steam
engines by the arrangement and construction of the govenor herein-before
described, by which two movements are effected, the one affecting the regulator
or throttle valve, and the other the expansion.

page_text: Sixthly, I claim the application to expansion valves of steam engines of a
piston or plunger for effecting the movement of the valve in one direction, the
motion in the other direction being effected by the movement of the engine by
a cam or other means, as herein-before described.
Seventhly, I claim the application to the valve gearing of steam engines, of
the arrangement and combination of apparatus by which a quick and a slow
motion at certain parts of its stroke is communicated to the slide valve, as
herein-before described.
Eighthly, I claim the application to the valve gearing of steam engines of
the arrangement and combination of apparatus by which, upon the disengage-
ment of the excentric rod, the slide valves will be caused to cover the ports or
passages and prevent ingress of steam to the cylinder for the purpose of
stopping the movements of the engine, as berein-before described.
In witness whereof, I, the said Robert Wilson, have hereunto set my
hand and seals this Third day of December, One thousand eight hundred
and forty-nine.
Signed, sealed, and delivered, in the
presence of
JOHN CLEGG,
ROBERT (L.s.) WILSON.
Sol",
AND BE IT REMEMBERED, that on the Third day of December, in the
year of our Lord 1849, the aforesaid Robert Wilson came before our said
Lady the Queen in Her Chancery, and acknowledged the Specification afore-
said, and all and everything therein contained and specified, in form above
written. And also the Specification aforesaid was stamped according to the
tenor of the Statute made for that purpose.
Enrolled the Seventh day of December, in the year of our Lord One
thousand eight hundred and forty-nine.