IMPROVEMENTS IN REGULATING THE VELOCITY OF STEAM ENGINES
Year: 1846

page_text: TO ALL TO WHOM THESE PRESENTS SHALL COME, I, MOSES
POOLE, of the Patent Office, London, Gentleman, send greeting.
WHEREAS Her present most Excellent Majesty Queen Victoria, by Her
Royal Letters Patent under the Great Seal of the United Kingdom of Great
Britain and Ireland, bearing date at Westminster, the Twenty-ninth day of June,
in the tenth year of Her reign, did, for Herself, ITer heirs and successors, give
and grant unto me, the said Moses Poole, my cñors, admors, and assigns, IIer
especial licence, full power, sole privilege and authority, that I, the said Moses
Poole, my exors, adññiors, and assigns, or such others as I, the said Moses
Poole, my exois, adiñors, or assigns, should at any time agree with, and no
others, from time to time and at all times during the term of years therein
expressed, should and lawfully might make, use, exercise, and end, within
England, Wales, and the Town of Berwick-upon-Tweed, the Invention of
"IMPROVEMENTS IN REGULATING THE VELOCITY OF STEAM ENGINES," communicated
from a Foreigner residing abroad; in which said Letters Patent is contained
a proviso that I, the said Moses l'oole, should cause a particular description
of the nature of my said Invention, and in what manner the same is to be
performed, by an instrument in writing under my hand and seal, to be iniolled

page_text: in Her said Majesty's High Court of Chancery within six calendar months
next and immediately after the date of the said in part recited Letters
Patent, as in and by the same, reference being thereunto had, will more fully
and at large appeal
NOW KNOW YE, that in compliance with the said proviso, I, the said
Moses Poole, do hereby declare that the nature of the said Invention, and the
manner in which the same is to be performed, are fully described and
ascertained in and by the following statement thereof, reference being had to
the Drawings hereunto annexed, and to the figures and letters marked theicon,
that is to say
The Invention consists in certain means of arranging apparatus to be used
in connection with a governor similar to that now used with steam engines, and
such apparatus is capable of being worked in two ways, as I will now proceed to
describe The first arrangement consists of employing the power of compressed
air, forced into a chamber by means of a pump worked by the engine, and the
an in this chamber is kept in a more or less compressed state, according to the
resistance of the engine. The piston 1od of a piston which is acted upon by
the compressed air communicates with a valve, so as to regulate more or less
the opening of this valve through which the steam is supplied to the steam
cylinder. By this arrangement the engine is kept in a uniform state, whatever
be the variation in the work of the engine, and only that quantity of steam
which would be required for a correct working of the engine is employed
The second mode of arranging the apparatus is by using the pressure of the
atmosphere, acting upon a piston to press it into a vacuum, in place of com-
pressed air The rod of the piston communicates with the valve as before,
for the purpose of opening on shutting it The Drawing shows the application
of both these modes of carrying out this Invention
ratus
Figure shows a vertical section of the arrangement of apparatus in which
compressed air is employed as the means of working it, and Figure 2 shows a
vertical section of the arrangement of apparatus in which a vacuum is employed
In Figure 1, a is the cylinder, and b the piston for forcing air into the appa-
The rod cof the piston bis connected to the axis of the fly wheel of
the engine, a is the cylinder of a double-action pump, into which air passes
through the openings g, there being valves, h, to such openings, and the air is
forced out through the openings (which have valves, 3,) into the receiver or
chamber . the upper part of which is formed into a cylinder l' In this
cylinder works a piston k, the rod m of which passes up and communicates
with the cock or valve for the supply of steam to the steam cylinder, and the
2

page_text: q
piston has an up and down movement, given more or less according to the
state of compression of the air in the chamber d is a counter weight. placed
at the upper part of the rod m, to counterbalance the weight of the steam
salve and the friction of the connecting pieces This weight receives from the
piston the impulses, and communicates them immediately to the valve, so as to
regulate the working of the engine. e is a grooved comical plug, a section of
which is shown separately at Figure 3, it is intended to aid in regulating the
working of the apparatus, by permitting an escape of ur from the chamber 7,
an excess of air which other wise tend to destroy the speed of the governoi and
of the engine This operation should be effected at first, and then it will
escape through this opening as a continuous curient of air
7 IS a tube
through which the air escapes from the receiver 7; it is closed at one end by a
cock g, which is opened or shut by a handle r, in communication with the rod s
of a governor,
which is similar to those ordinarily used in steam engines This
governor thus becomes an auxiliary to the air regulator, inasmuch as that by
the diawing together or separating of the balls the shutting or opening of the
cock is governed, and the escape of air from the cylinder is regulated. The
mode of working the apparatus when compressed air is employed is as follows:-
The apparatus being worked by the shaft of the fly wheel of the engine, the
degree of compressibility of the air in the chamber b is modified by the screw e,
the opening through which may be larger or smaller, as required. Then the
following effects will be produced -The air being continually drawn in from
the atmosphere, and forced by the piston b into the chamber I, will press under
the piston k, or the piston will be held in suspension by the escape of the air
through the plug e, and through the cock 7. Thus, for example, when the
burden is taken off the engine, the speed of it would be instantly increased, when
by the spreading out of the balls of the governor the cock 9 will be shut, and the
air will then act upon the piston k, forcing it upwards by the increased pressure
of the air, the effect of which will be to shut off the steam, and thus bring back
the engine to its original working, notwithstanding the burden is removed
on the contrary, the work of the engine is encreased, the balls of the ordinary
governor will be drawn together, and consequently will open the cock q, to
allow the air in the chamber to escape, and the piston k, not being acted
upon by the compressed air, will descend, and in so doing will draw down the
rod which is in communication with the steam supply valve, by which a
greater quantity of steam will be supplied to the steam cylinder, so that the
speed may be kept up notwithstanding the increased work of the engine
By this arrangement of compressed an regulator at any part of each stroke of
If,

page_text: the piston, the valve can be closed according to the resistance to the engine
I would remark that the apparatus shewn in the Diawing is for an engine
from one to six horse power, but when the engine is of greater power the
capacity is to be inci cased one tenth for cach power. I will now describe
the mode of working with the vacuum instead of the compressed air, as shown
at Figure 2 Most of the parts in this Figure are similar to those previously
described, and it will be seen they are marked with similar letters, but the
fixing of the valves h and jis reversed, to allow of the air being forced out
from the chamber 7, instead of its having to be drawn therein. The piston k
is held in suspension in the chamber also by the depression of the air.
The cylinder a, which causes the vacuum in the chamber 1, communicates
with it through the tube t. At the lower part of the chamber 7, at 1, is open to
the atmosphere. Instead of the conical plug e, a cock e, is employed for the
same purpose, to regulate the speed of the engine when working without any
resistance; only in place of its allowing the air to escape, as in the other
apparatus, it allows the air to enter when required, to keep up the original
speed The cock 7 also, when it is open, allows the air to enter, in place of
allowing it to escape. The action of the air is completely reversed in working
this apparatus. In putting it to work, the cylinder a tends to produce a
vacuum in the chamber 1, and the cock e allows of a sufficient quantity of air
to be admitted from without, according to the original speed, and the cock q
will open oi shut, according to the varying speed of the engines, by the aid of
the governo, as before described, so as to allow the au to enter or not into
the chamber. The effect of this will be, that the raising or lowening of the
piston will open or close the steam valve in proportion as the vacuum is
more or less kept up in the chamber 6. In the Drawing the governor is shewn
as of the usual size, but that is not necessary, as when working in combination
with this apparatus may be considerably reduced.
Baving thus described the nature of the Invention, and the manner of per-
forming the same, I would have it understood that I do not confine myself to
the precise arrangements herein described. so long as the character of the
Invention be retained But what I claim is, the modes of arranging apparatus
for regulating the velocity of steam engines as herein described.
In witness whereof, I, the said Moses Poole, have hereunto set my hand
and seal, this Twenty-fourth day of December, in the year of our
Lord one thousand eight hundred and forty-six.
MOSES (L.s.) POOLE.

page_text: AND BE IT REMEMBERED, that on the Twenty-fourth day of December
in the year of our Loid 1846, the aforesaid Moses Poole came before our said
Lady the Queen in Her Chancery, and acknowledged the Specification afore-
said, and all and every thing 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.