CERTAIN IMPROVEMENTS IN MACHINERY OR APPARATUS FOR GOVERNING OR REGULATING THE SPEED OF STEAM ENGINES OR OTHER MOTIVE POWER ENGINES
Year: 1854

page_text: LETTERS PATENT to William Crosland, of Hulme, in the County of
Lancaster, Engineer, for the Invention of "CERTAIN IMPROVEMENTS IN
MACHINERY OR APPARATUS FOR GOVERNING OR REGULATING THE SPEED OF
STEAM ENGINES OR OTHER MOTIVE POWER ENGINES."
Sealed the 6th February 1855, and dated the 14th August 1854.
PROVISIONAL SPECIFICATION left by the said William Crosland at the
Office of the Commissioners of Patents, with his Petition, on the 14th
August 1854.
I, WILLIAM CROSLAND, of Hulme, in the County of Lancaster, Engineer,
do hereby declare the nature of the said Livention for "CERTAIN IMPROVEMENTS
IN MACHINERY OR APPARATUS FOR GOVERNING OR REGULATING THE SPEED OF STEAM
ENGINES OR OTHER MOTIVE POWER ENGINES" to be as follows:-
On a shaft of the engine I employ a worm or screw, fitting or sliding
loosely, but so as to partake of the revolution of the said shaft. To the end
of the said worm is attached a lever, connected with the steam valve or other
apparatus which shall regulate the motive power, this worm having a
tendency to close the said valve or apparatus by sliding along the shaft; the
fulcrum upon which this worm is made to act is removed by each vibration of
a pendulum or balance wheel, the worm being allowed to move in an opposite
direction, to the extent of one thread, by means of a weight, which motion has
a tendency to open the said valve or apparatus.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said William Crosland in the Great Seal Patent Office on the
14th February 1855.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, WILLIAM
CROSLAND, of Hulme, in the County of Lancaster, Engineer, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Fourteenth day of August, in the year of our Lord
One thousand eight hundred and fifty-four, in the eighteenth year of Her
reign, did, for Herself, Her heirs and successors, give and grant unto me,
the said William Crosland, Her special license that I, the said William
Crosland, my executors, administrators, and assigns, or such others as I,
the said William Crosland, 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 IMPROVEMENTS IN MACHINERY OR APPARATUS FOR GOVERNING OR REGU-
LATING THE SPEED OF STEAM ENGINES OR OTHER MOTIVE POWER ENGINES," upon the
condition (amongst others) that I, the said William Crosland, by an instru-
ment in writing under my hand and seal, 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 William Crosland, 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 and accompanying Drawings (that is to say) :-
My improvements in machinery or apparatus for governing or regulating the
speed of steam engines or other motive power engines consist in the employ-
ment of a worm or screw on a shaft connected with and driven by the steam
or other motive power engine, fitting or sliding loosely, but so as to partake of
the revolution of the said shaft. To the end of the said worm is attached a
lever, connected with the steam valve or other apparatus which shall regulate
the motive power, this worm having a tendency to close the said valve or
apparatus by sliding along the shaft; the fulcrum upon which this worm is
made to act is removed by each vibration of a pendulum or balance wheel, the
worm being allowed to move in an opposite direction, to the extent of one

page_text: thread, by means of a weight, which motion has a tendency to open the said
valve or apparatus.
In order that this Invention may be the better understood and explained in
detail, I have hereunto attached two Sheets of Drawing.
Fig. 1, Sheet 1, represents a front elevation of the apparatus (partly
sectional), showing the peculiarly shaped screw, with pendulum attached ;
Fig. 2 exhibits a side elevation of the same; and Fig. 3, a plan or top view ;
Fig. 4 represents a detached view of escapement nut or pallets. a is a
worm or screw, of peculiar form, shown in section. 1, 2, 3, 4, 5, 6, 7, are
successive portions of the thread or spiral rim. b is a swivel joint connecting
the screw to the throttle valve; c is the nut, in which the screw works, and
which also acts as an escapement; d is a shaft, turned by the engine, and
fitted fast into the coupling e, in which also the shaft end of the worm or screw
a is fitted loosely; f is a flat steel cotter or key, passing through the shaft a,
and projecting on both sides, so as to come into contact with the two flanges
of the coupling e, and receive from it a rotary motion, it yet remaining at
liberty to move up and down the length of the coupling; 9, 9, are two radiating
bars, moving in fixed centres h, h, guiding and entirely supporting the escape-
ment nut c, causing it to move easily and to maintain a perfectly horizontal
position; i, i, are two pieces of leather, cloth, or other flexible material, fastened
to the radius bars and escapement nut by small bolts or screws; k, k, are two
levers, fixed on the centres h, h, and connected together by the rod l; m is the
pendulum, fixed upon a steel pivot n, working between two hardened centres
(Fig. 2) o is a round pin or stud, fixed in the pendulum rod, and fitting into
the recess p of the connecting rod in such a manner that each vibration of
the pendulum puts in motion the connecting rod and the levers k, k, which,
being fastened to the centres h, h, put in motion the radius bars and the
escapement nut c.
Suppose now the engine is running at its usual speed, and the worm shaft
makes the same number of revolutions as the crank shaft of the engine, for
every revolution of the worm it rises one thread in the nut; let the pendulum
then be set to such a length that it shall vibrate exactly the same number as
the engine, that is, two vibrations for every revolution; at each vibration of
the pendulum the escapement nut slips from under the thread of the worm on
one side, catching it again on the opposite side of the worm, thus allowing it to
fall half a thread for every vibration, or one whole thread for every backwards
and forwards movement of the pendulum; the inclines on the thread of the
screw acting against the inclines of the pallets or escapement nut keep the
pendulum in motion. Suppose that by throwing off weight the engine begins

page_text: to go quicker, the worm or screw will also move quicker, and will thus rise
more than one thread during the time the pendulum is making two vibra-
tions. Now, the screw is directly connected with the throttle valve in such a
manner that when the worm is rising the valve is closing, and when the worm
drops down the valve drops open. Thus it will be evident that for the slightest
increase in the speed of the engine there will be a simultaneous closing of the
valve; and whenever the engine by decrease of speed ceases to screw up the
worm in the same proportion as the pendulum allows it to drop, it must
necessarily resume a lower position, at the same time opening the valve. In
Sheet 2, Fig. 5 represents a side elevation, and is another arrangement of
this Invention, wherein a balance wheel is employed in lieu of a pendulum.
Fig. 6 is a front elevation of the same, illustrating the position that the balance
wheel always has a tendency to assume. Fig. 7 is a plan or top view of
Figures and 6, and Fig. 8 represents the pallets. a is a shaft, turned by
the engine in such a manner that it remains at liberty to move up and down
easily. On this shaft is an ordinary worm or screw 6 (Fig. 5). At the lower
end of shaft à is a swivel, attaching the shaft a to the throttle valve. Attached
to swivel c is a short spiral spring, of sufficient strength to move the valve
under ordinary circumstances without closing. d is a short shaft working
between two centres e, e; on this shaft are keyed two wheels fand g (Fig. 7).
fis an ordinary worm wheel, in gear with worm b, from which it receives
motion ;9 is an escapement wheel, having on its outer rim a number of semi-
circular teeth or pegs, made of steel or some durable material; h, h, are the
pallets, whose action is seen more clearly by referring to Fig. 8; i is a lever,
fixed on the same centre as the pallets, and forming the connection between
the pallets and the balance wheel ; is a coiled spring, having a tendency
always to bring back the balance wheel to the position shewn in Fig. 6; m is
a flat disc, in which is fixed the steel pin or stud n, fitting into a recess in the
lever ; is another steel pin, fitting into a recess of the disc m when at rest,
but slides along the edge of the disc m during its vibrations, and maintains
the lever in its position; p is the regulator, used to alter the length of the
spring, and thus affect the speed of the engine. Supposing now the engine
to be put in motion at its usual speed, the worm b, acting upon the worm
wheel, puts in motion the shaft d and escapement wheel, causing the
semicircular teeth to press upon the inclined part of the escapement h, which
being thus put in motion moves also the lever i, the stud pin n, and the
balance wheel k, which being thus put in motion will vibrate at certain fixed
periods, at each vibration moving the escapement h, and liberating one tooth
of the escapement wheel g, thus allowing it to revolve at one fixed speed.

page_text: Supposing, however, that by throwing weight off the engine its speed is
increased, the worm, b will then have a tendency to force round the worm
wheel and also the escapement wheel at an increased speed; these wheels,
however, being held perfectly fast, causes the worm b and also the shaft a to
slide upwards through its bearings, carrying with it the lever of the throttle
valve and shutting off a portion of the steam. If the speed of the engine still
continues, the worm will also continue to move upwards till the valve is
entirely shut. If, on the contrary, the engine should be moving too slow, the
escapement h will suffer the worm to fall by its own weight till the valve is
wide open. Either the balance wheel or the pendulum may be employed
in either arrangement of the apparatus, as preferred.
Having now particularly described the nature of my Invention, and the
manner in which the same is to be put into practical effect, I wish it to be
distinctly understood that I claim the novel and peculiar construction and
arrangement of the machinery or apparatus herein particularly described and
set forth, and fully illustrated in the Drawings attached to these Presents, more
particularly the application of a detached pendulum or balance wheel, that is,
a pendulum hung in such a manner that it shall receive its impulse in the
centre of the vibration, or when in a perpendicular position, the remainder of
the vibration being performed free from any contact or influence from the
engine or other foreign cause.
In witness whereof, I, the said William Crosland, have hereunto set
my hand and seal, this Thirteenth day of February, in the year of our
Lord One thousand eight hundred and fifty-five.
WILLIAM CROSLAND.
(L.S.)